JP7792927B2 - Flow path switching device - Google Patents

Description

The technology disclosed in this specification relates to a flow path switching device that switches fluid flow paths in a fluid circuit.

One example of this type of technology is the flow path switching device described in Patent Document 1 below. As described in paragraphs [0156] to [0166] and Figure 10 of Patent Document 1, this device comprises a housing 71 and a valve body portion 73 disposed inside the housing 71. The valve body portion 73 includes a fixed disk 75 and a drive disk 74 that is driven to rotate. The fixed disk 75 is disposed so as to divide the interior of the housing 71, and has multiple communication passages 75a, 75b. The drive disk 74 is formed in the shape of a plate sized to be able to block the communication passages 75a, 75b.

Japanese Patent Application Laid-Open No. 2022-21966

In the device described in Patent Document 1, it is conceivable to provide sealing members around the communication passages 75a and 75b between the fixed disk 75 and the drive disk 74. In this case, when the drive disk 74 is rotated to switch between the communication passages 75a and 75b, the edges of the communication passages 75a and 75b or the edges of the drive disk 74 cross the sealing members with high surface pressure, which could cause sliding wear on the sealing members or cause them to become caught and become dislodged.

This disclosed technology was developed in light of the above circumstances, and its purpose is to prevent the seal member from coming loose due to sliding wear or snagging when the drive disk rotates in a flow path switching device in which a seal member is provided at least between the fixed disk and drive disk.

To achieve the above object, the technology described in claim 1 is a flow path switching device comprising a housing and a valve body portion disposed inside the housing, the valve body portion including a fixed disk, a drive disk stacked on the fixed disk and rotating relative to the fixed disk, and a rotating shaft for rotating the drive disk, the housing, fixed disk, and drive disk each having a plurality of communication passages which are configured to connect as the drive disk rotates to form a fluid flow path, and a sealing member provided in the flow path to prevent fluid leakage at least between the fixed disk and the drive disk, wherein the tip of the rotating shaft is configured to be able to abut and engage with the fixed disk, and the fixed disk is configured to be able to move back and forth in the axial direction by abutting and engaging with the tip of the rotating shaft as it rotates.

In the configuration of the above technology, the drive disk rotates relative to the fixed disk as the rotating shaft rotates. At this time, the sliding resistance associated with the rotation of the drive disk is reduced at least in the seal member between the fixed disk and drive disk. That is, with the above configuration, the tip of the rotating shaft is arranged to be able to abut and engage with the fixed disk, and the fixed disk is configured to be able to move back and forth in the axial direction as the tip of the rotating shaft abuts and engages with it as it rotates. Therefore, when the drive disk rotates in conjunction with the rotation of the rotating shaft, the fixed disk moves back and forth in the axial direction, widening the gap between the housing and drive disk and the gap between the fixed disk and drive disk. This reduces the surface pressure applied to the seal members between the housing and drive disk and between the fixed disk and drive disk, and reduces the sliding resistance of each seal member 17, 18.

To achieve the above object, the technology described in claim 2 is the technology described in claim 1, wherein the tip of the rotating shaft includes shaft convex portions and shaft concave portions aligned in the circumferential direction, the fixed disk includes disc concave portions and disc convex portions that can abut and engage with the shaft convex portions and shaft concave portions, and the shaft convex portions and shaft concave portions as well as the disc concave portions and disc convex portions include side portions that are inclined in the circumferential direction.

In addition to the effects of the technology described in claim 1, the configuration of the above technology allows for two states to be achieved by rotating the rotating shaft: a state in which the shaft convex portion and the disk convex portion abut (convex-convex abutment state), and a state in which the shaft convex portion and shaft concave portion engage with the disk concave portion and disk convex portion (convex-concave engagement state). In the convex-convex abutment state, the fixed disk moves axially, widening the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk, reducing the surface pressure applied to the sealing members between the housing and the drive disk and between the fixed disk and the drive disk. In contrast, in the convex-concave engagement state, the fixed disk moves axially, returning the gap between the housing and the drive disk and between the fixed disk and the drive disk to their original values, restoring the surface pressure applied to the sealing members between the housing and the drive disk and between the fixed disk and the drive disk to their original states. Switching between the convex-convex abutment state and the convex-concave engagement state involves a state in which the shaft convex portion and shaft concave portion come into contact with the inclined side surfaces of the disk concave portion and the disk convex portion.

To achieve the above objective, the technology described in claim 3 is the technology described in claim 2, in which the top of at least one of the shaft convex portion and the disc convex portion is formed as a flat surface or a convex curved surface, and the bottom of at least one of the disc concave portion and the shaft concave portion is formed as a flat surface or a concave curved surface.

With the configuration of the above technology, in addition to the effect of the technology described in claim 2, when the shaft protrusion and disc protrusion are in contact, the top of at least one of the shaft protrusion and disc protrusion is formed into a flat surface or a convex curved surface, so when the rotating shaft is rotated from this state, the axial position of the rotating shaft does not change suddenly. Furthermore, because the bottom of at least one of the disc recess and shaft recess is formed into a flat surface or a concave curved surface, when the rotating shaft is rotated with the shaft protrusion and shaft recess engaged with the disc recess and disc protrusion, the axial position of the rotating shaft does not change suddenly.

To achieve the above object, the technology described in claim 4 is the technology described in claim 2, wherein the disk recess has a V-shaped gently sloping concave surface at its bottom and a steeply sloping surface that continues from the gently sloping concave surface to the disk protrusion and forms the side of the disk protrusion; the shaft protrusion has a V-shaped gently sloping convex surface at its top that matches the gently sloping concave surface; and the side of the shaft protrusion that continues from the gently sloping convex surface has a steeply sloping surface that matches the steeply sloping surface of the side of the disk protrusion.

According to the configuration of the above technology, in addition to the effect of the technology described in claim 2, when the shaft protrusion of the rotating shaft engages with the disk recess of the fixed disk and the convex, gently inclined surface of the shaft protrusion makes contact with the gently inclined concave surface of the disk recess, when the rotating shaft begins to rotate, the shaft protrusion begins to slide against the disk recess at a gentle slope, sliding due to the contact surface between the convex, gently inclined surface and the concave, gently inclined surface. Furthermore, as the rotation of the rotating shaft progresses, the contact surface between the disk recess and the shaft protrusion transitions from the contact surface between the gently inclined concave surface and the gently inclined convex surface to the contact surface between the steeply inclined surfaces, and they begin to slide due to the contact surface.

To achieve the above objective, the technology described in claim 5 is a technology described in any one of claims 1 to 4, in which the drive disk and the rotating shaft are connected so as to be capable of relative movement in the rotational and axial directions.

With the configuration of the above technology, in addition to the effects of the technology described in any one of claims 1 to 4, the drive disk and rotating shaft are connected so that they can move relative to each other in the rotational and axial directions. Therefore, when the drive disk rotates and applies surface pressure to the seal member, the drive disk moves in the rotational and axial directions within the gap between the housing and the fixed disk, and is positioned in a position that balances the reaction force of the seal member.

To achieve the above objective, the technology described in claim 6 is the technology described in claim 5, in which the connection between the rotating shaft and the drive disk has a gap in the rotational direction.

With the configuration of the above technology, in addition to the effect of the technology described in claim 5, the connection between the rotating shaft and the drive disk has a gap in the rotational direction, so when the rotating shaft is rotated, the rotating shaft rotates freely by the amount of the gap at the connection.

To achieve the above objective, the technology described in claim 7 is the technology described in claim 6, in which the idling angle at which the rotating shaft idles through the gap when the tip of the rotating shaft transitions from a state in which it engages with the fixed disk to a state in which it abuts, and the switching angle at which the drive disk rotates to switch the flow path are set to the same angle.

With the configuration of the above technology, in addition to the effect of the technology described in claim 6, when the tip of the rotating shaft transitions from an engaged state with the fixed disk to an abutting state, i.e., when the fixed disk moves axially and the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk widens, the idling angle of the rotating shaft and the switching angle of the drive disk when switching the flow path are set to the same angle. Therefore, by rotating the rotating shaft in the opposite direction by the switching angle and idling angle, it is possible to return the rotational positions of the rotating shaft and the drive disk to their original states.

To achieve the above object, the technology described in claim 8 is the technology described in claim 7, further comprising a drive means for driving the rotating shaft to rotate and a control means for controlling the drive means, and the control means controls the drive means to rotate the rotating shaft and switch the flow path with the tip of the rotating shaft abutting the fixed disk, then rotate the rotating shaft in the opposite direction and stop the rotation of the rotating shaft with the tip of the rotating shaft engaged with the fixed disk.

With the configuration of the above technology, in addition to the effect of the technology described in claim 7, the control means controls the drive means to rotate the rotating shaft, switch the flow path when the tip of the rotating shaft abuts the fixed disk (widening the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk), then rotate the rotating shaft in the opposite direction and stop rotation when the tip of the rotating shaft engages with the fixed disk (returning the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk to their original state). This makes it possible to reliably return the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk to their original state after switching the flow path.

The technology described in claim 1 can prevent the seal member from coming loose due to sliding wear or snagging when the drive disk rotates.

The technology described in claim 2 not only achieves the effect of the technology described in claim 1, but also allows for smooth switching between the convex-convex abutment state and the convex-concave engagement state.

The technology described in claim 3 not only achieves the effect of the technology described in claim 2, but also further reduces sliding wear on the sealing member.

In addition to the effects of the technology described in claim 2, the technology described in claim 4 can reduce the drive torque required to rotate the rotating shaft when the rotating shaft begins to rotate from a state in which the shaft protrusion is engaged with the disk recess, thereby suppressing wear on the shaft protrusion and disk recess.

The technology described in claim 5, in addition to the effects of the technology described in any one of claims 1 to 4, can further reduce the surface pressure applied to the seal member when the drive disk rotates, thereby improving the durability of the seal member.

The technology described in claim 6 achieves the same effect as the technology described in claim 5, but it also makes it possible to rotate the rotating shaft without rotating the drive disk, thereby widening the gap between the housing and the drive disk and the gap between the fixed disk and the drive disk.

The technology described in claim 7 achieves the same effect as the technology described in claim 6, and also makes it possible to match the flow path switching operation when the rotating shaft is rotated in one direction with the flow path switching operation when the rotating shaft is rotated in the opposite direction.

The technology described in claim 8 not only achieves the effect of the technology described in claim 7, but also ensures the sealing properties of the sealing member.

FIG. 2 is a perspective view showing a flow path switching device according to the first embodiment. FIG. 2 is a front view showing the flow path switching device in the first embodiment. FIG. 2 is a plan view showing the flow path switching device according to the first embodiment. FIG. 3 is a bottom view showing the flow path switching device in the first embodiment. FIG. 2 is an exploded perspective view showing the flow path switching device according to the first embodiment. FIG. 4 is a cross-sectional view of the flow path switching device taken along line AA of FIG. 3 according to the first embodiment. FIG. 2 is a plan view showing a rotary disk in the first embodiment. FIG. 3 is an exploded perspective view showing an upper housing and a rotating shaft in the first embodiment. FIG. 2 is a perspective view showing a fixed disk in the first embodiment. FIG. 10 is an enlarged view showing the engaged structure of the fixed disk shown in FIG. 9 in the first embodiment. FIG. 3 is a front view showing a rotation shaft in the first embodiment. FIG. 12 is a perspective view showing a portion of the engagement structure surrounded by a dashed-dotted circle in FIG. 11 according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a simplified state before operation of the upper housing, the rotary disc, the fixed disc, the rotary shaft, and the like in the first embodiment. FIG. 14 is a cross-sectional view taken along line BB in FIG. 13 showing the rotary disk and the rotary shaft in the first embodiment. FIG. 10 is a cross-sectional view illustrating a simplified operation start state of the upper housing, the rotary disc, the fixed disc, the rotary shaft, and the like in which only the rotary shaft has rotated in the first embodiment. FIG. 16 is a cross-sectional view taken along line CC in FIG. 15 showing the rotary disk and the rotary shaft in the first embodiment. FIG. 10 is a cross-sectional view illustrating the first embodiment, in a simplified manner, an operating state of the upper housing, the rotary disk, the fixed disk, the rotary shaft, and the like when the rotary disk rotates. FIG. 18 is a cross-sectional view taken along line DD in FIG. 17, showing the rotating disk and the rotating shaft in the first embodiment. FIG. 10 is a cross-sectional view illustrating an outline of the upper housing, the rotary disk, the fixed disk, the rotary shaft, etc. in the final state after the rotary shaft and the rotary disk have further rotated in the first embodiment. FIG. 20 is a cross-sectional view taken along line E-E in FIG. 19 showing the rotating disk and the rotating shaft in the first embodiment. FIG. 11 is a plan view illustrating a state in which an upper housing and a drive unit are removed from the flow path switching device according to a second embodiment. FIG. 22 is an enlarged plan view of the through-hole and the rotary shaft (encircled by the dashed line) in FIG. 21 according to the second embodiment. FIG. 10 is a perspective view showing a rotation shaft in the second embodiment. FIG. 24 is an enlarged perspective view of the engagement structure at the tip of the rotary shaft shown in FIG. 23 according to the second embodiment. FIG. 10 is a plan view showing a fixed disk in the second embodiment. FIG. 26 is an enlarged perspective view of the engaged structure of the fixed disk shown in FIG. 25 according to the second embodiment. 21A and 21B show the "initial state" of the flow path switching device according to the second embodiment, in which (A) is an image diagram showing the engagement relationship between the through hole of the rotating disk and the rotating shaft, (B) is an image diagram showing the change in lift of the rotating shaft with respect to the angle of the rotating shaft, (C) is a plan view showing the rotational position of the through hole and the rotating shaft, and the positional relationship between the disk convex portion, the disk concave portion and the shaft convex portion, and (D) is a plan view similar to FIG. 21 showing the rotational position of the rotating disk and the rotary connecting passage. 27(A) is an image diagram similar to FIG. 27(A), FIG. 27(B) is an image diagram similar to FIG. 27(B), FIG. 27(C) is a plan view similar to FIG. 27(C), and FIG. 27(D) is a plan view similar to FIG. 27(D), showing the flow path switching device in a "45° rotation state" according to the second embodiment. 27A and 27B show the "90° rotated state" of the flow path switching device according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the "135° rotation state" of the flow path switching device according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "90° rotated back state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "135° re-rotation state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the "180° rotated state" of the flow path switching device according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "135° return rotation state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "90° rotated back state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "45° rotation back state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "re-90° rotation state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the flow path switching device in the "45° rotation back state" according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the "return initial state" of the flow path switching device according to the second embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, (C) is a plan view similar to FIG. 27C, and (D) is a plan view similar to FIG. 27D. 27A and 27B show the "initial state" of the flow path switching device according to the third embodiment, where (A) is an image diagram similar to FIG. 27A, (B) is an image diagram similar to FIG. 27B, and (C) is a plan view similar to FIG. 27D. 40(B) is an image diagram similar to FIG. 40(B), and FIG. 40(C) is a plan view similar to FIG. 40(C). 41(B) is an image diagram similar to FIG. 41(B), and FIG. 41(C) is a plan view similar to FIG. 41(C). 41(B) is an image diagram similar to FIG. 41(B), and FIG. 41(C) is a plan view similar to FIG. 41(C), showing the flow path switching device in a "45° return rotation state" according to the third embodiment. 41(A) is an image diagram similar to FIG. 41(A), FIG. 41(B) is an image diagram similar to FIG. 41(B), and FIG. 41(C) is a plan view similar to FIG. 41(C) in the "return initial state" of the flow path switching device according to the third embodiment. 40(A) is an image diagram similar to FIG. 40(A), FIG. 40(B) is an image diagram similar to FIG. 40(B), and FIG. 40(C) is a plan view similar to FIG. 40(D), showing the "initial state" of the flow path switching device according to the fourth embodiment. 45A, 45B, and 45C show the flow path switching device in a "22.5° rotation state" according to the fourth embodiment, where FIG. 45A is an image diagram similar to FIG. 45A, FIG. 45B is an image diagram similar to FIG. 45B, and FIG. 45C is a plan view similar to FIG. 45C. 45A, 45B, and 45C show the flow path switching device in a "67.5° rotation state" according to the fourth embodiment, where FIG. 45A is an image diagram similar to FIG. 45A, FIG. 45B is an image diagram similar to FIG. 45B, and FIG. 45C is a plan view similar to FIG. 45C. 45(B) and 45(C) show the flow path switching device in the "45° return rotation state" according to the fourth embodiment, where (A) is an image diagram similar to FIG. 45(A), (B) is an image diagram similar to FIG. 45(B), and (C) is a plan view similar to FIG. 45(C). 45A, 45B, and 45C show the "return initial state" of the flow path switching device according to the fourth embodiment, where FIG. 45A is an image diagram similar to FIG. 45A, FIG. 45B is an image diagram similar to FIG. 45B, and FIG. 45C is a plan view similar to FIG. 45C. 40(A) is an image diagram similar to FIG. 40(A), FIG. 40(B) is an image diagram similar to FIG. 40(B), and FIG. 40(C) is a plan view similar to FIG. 40(D), showing the "initial state" of the flow path switching device according to the fifth embodiment. 5A and 5B show the "45° rotated state" of the flow path switching device according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the "90° rotated state" of the flow path switching device according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the "135° rotation state" of the flow path switching device according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the flow path switching device in the "90° rotated back state" according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the flow path switching device in the "45° return rotation state" according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the "re-90° rotation state" of the flow path switching device according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the flow path switching device in the "45° return rotation state" according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. 5A and 5B show the "return initial state" of the flow path switching device according to the fifth embodiment, where (A) is an image diagram similar to FIG. 50A, (B) is an image diagram similar to FIG. 50B, and (C) is a plan view similar to FIG. 50C. FIG. 13 is a perspective view showing the upper surface side of the flow path switching device according to the sixth embodiment. FIG. 13 is a perspective view showing the bottom side of the flow path switching device according to the sixth embodiment. FIG. 13 is a plan view showing a flow path switching device according to a sixth embodiment. FIG. 13 is a plan view showing a state in which an upper housing and a drive unit are removed from the flow path switching device according to the sixth embodiment. FIG. 63 is an enlarged plan view showing the through-hole and the rotary shaft in FIG. 62 according to the sixth embodiment. FIG. 13 is a perspective view showing a rotation shaft in the sixth embodiment. FIG. 65 is an enlarged perspective view of the engagement structure at the tip of the rotating shaft shown in FIG. 64 according to the sixth embodiment. FIG. 13 is a plan view showing a fixed disk in the sixth embodiment. FIG. 67 is an enlarged perspective view of the engaged structure of the fixed disk shown in FIG. 66 according to the sixth embodiment. 27(A) is an image diagram similar to FIG. 27(A), FIG. 27(B) is an image diagram similar to FIG. 27(B), FIG. 27(C) is a plan view similar to FIG. 27(C), and FIG. 27(D) is a plan view similar to FIG. 27(D) according to the sixth embodiment. 6. This figure shows the "30° rotation state" of the flow path switching device according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6. This figure shows the "60° rotation state" of the flow path switching device according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6A and 6B show the flow path switching device in the "30° rotated back state" according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68A, (B) is an image diagram similar to FIG. 68B, (C) is a plan view similar to FIG. 68C, and (D) is a plan view similar to FIG. 68D. 6. The sixth embodiment shows the "return 0° rotation state" of the flow path switching device, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6A and 6B show the "30° re-rotation state" of the flow path switching device according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68A, (B) is an image diagram similar to FIG. 68B, (C) is a plan view similar to FIG. 68C, and (D) is a plan view similar to FIG. 68D. 6. The sixth embodiment shows the "60° re-rotation state" of the flow path switching device, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6A and 6B show the "90° rotated state" of the flow path switching device according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68A, (B) is an image diagram similar to FIG. 68B, (C) is a plan view similar to FIG. 68C, and (D) is a plan view similar to FIG. 68D. 6. The sixth embodiment shows the flow path switching device in a "60° rotation return state", where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6A and 6B show the flow path switching device in the "30° rotated back state" according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68A, (B) is an image diagram similar to FIG. 68B, (C) is a plan view similar to FIG. 68C, and (D) is a plan view similar to FIG. 68D. 6. The sixth embodiment shows the "return 0° rotation state" of the flow path switching device, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6. The sixth embodiment shows the "-30° rotation state" of the flow path switching device, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), (C) is a plan view similar to FIG. 68(C), and (D) is a plan view similar to FIG. 68(D). 6A and 6B show the "return initial state" of the flow path switching device according to the sixth embodiment, where (A) is an image diagram similar to FIG. 68A, (B) is an image diagram similar to FIG. 68B, (C) is a plan view similar to FIG. 68C, and (D) is a plan view similar to FIG. 68D. 13 is a flowchart showing an example of the contents of flow path switching control according to the sixth embodiment. 13 is a flowchart showing an example of the contents of flow path switching control according to the sixth embodiment. 13 is a flowchart showing an example of the contents of flow path switching control according to the sixth embodiment. 68(A) and 68(B) show the "initial state" of the flow path switching device according to the seventh embodiment, where (A) is an image diagram similar to FIG. 68(A), (B) is an image diagram similar to FIG. 68(B), and (C) is a plan view similar to FIG. 68(D). 8A and 8B show the flow path switching device in a "30° rotation state" according to the seventh embodiment, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 8A and 8B show the flow path switching device in a "60° rotation state" according to the seventh embodiment, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 8A and 8B show the flow path switching device in the "30° rotated back state" according to the seventh embodiment, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 8A and 8B show the seventh embodiment and the "return 0° rotation state" of the flow path switching device, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 8A and 8B show the flow path switching device in the "-30° rotation state" according to the seventh embodiment, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 8A and 8B show the "return initial state" of the flow path switching device according to the seventh embodiment, where (A) is an image diagram similar to FIG. 84A, (B) is an image diagram similar to FIG. 84B, and (C) is a plan view similar to FIG. 84C. 40(A) shows the "initial state" of the flow path switching device according to the eighth embodiment, where (A) is an image diagram similar to FIG. 40(A), (B) is an image diagram showing the relationship between the engaging structure and the engaged structure, and (C) is the same image diagram as FIG. 40(B). 91(A) is an image diagram similar to FIG. 91(A), FIG. 91(B) is an image diagram similar to FIG. 91(B), and FIG. 91(C) is an image diagram similar to FIG. 91(C) relating to the eighth embodiment, showing the "45° rotation state" of the flow path switching device. 91(A) is an image diagram similar to FIG. 91(A), FIG. 91(B) is an image diagram similar to FIG. 91(B), and FIG. 91(C) is an image diagram similar to FIG. 91(C) relating to the eighth embodiment, showing the "90° rotated state" of the flow path switching device. 91(A) is an image diagram similar to FIG. 91(A), FIG. 91(B) is an image diagram similar to FIG. 91(B), and FIG. 91(C) is an image diagram similar to FIG. 91(C) relating to the eighth embodiment, showing the "45° return rotation state" of the flow path switching device. 91(A) is an image diagram similar to FIG. 91(A), FIG. 91(B) is an image diagram similar to FIG. 91(B), and FIG. 91(C) is an image diagram similar to FIG. 91(C) relating to the eighth embodiment, showing the "return initial state" of the flow path switching device. FIG. 13 is an image diagram illustrating the relationship between the engaging structure and the engaged structure when the rotating shaft is lifted down before switching the flow path according to the ninth embodiment. FIG. 13 is an image diagram illustrating the relationship between the engaging structure and the engaged structure when the rotating shaft is lifted up during flow path switching in the ninth embodiment. FIG. 13 is an image diagram illustrating the relationship between the engaging structure and the engaged structure when the rotating shaft is lifted up during flow path switching in the ninth embodiment. FIG. 13 is a conceptual diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft is lifted down before switching the flow path, according to a comparative example (eighth embodiment). FIG. 13 is a conceptual diagram relating to a comparative example (eighth embodiment) and showing the relationship between the engaging structure and the engaged structure when the rotating shaft is being lifted up during flow path switching. FIG. 13 is a conceptual diagram relating to a comparative example (eighth embodiment) and showing the relationship between the engaging structure and the engaged structure when the rotating shaft is lifted up during flow path switching. 13 is a graph showing the relationship between a change in the rotation angle of the rotary shaft and a change in the drive torque according to the ninth embodiment. FIG. 23 is an image diagram illustrating the relationship between the engaging structure and the engaged structure in a lift-down state before switching of the flow path according to the tenth embodiment. FIG. 104 is an enlarged conceptual diagram showing the ground contact portion of FIG. 103 according to the tenth embodiment. FIG. 23 is an image diagram illustrating the relationship between the engaging structure and the engaged structure at the start of flow path switching (at the initial drive when lift-up begins) in the tenth embodiment. FIG. 23 is an image diagram showing the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up) in the tenth embodiment. FIG. 23 is an image diagram showing the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up) in the tenth embodiment. FIG. 108 is an enlarged conceptual diagram showing the ground contact portion in FIG. 107 according to the tenth embodiment. FIG. 19 is an image diagram illustrating the relationship between the engaging structure and the engaged structure immediately after the top of the shaft protrusion has climbed over the top of the disk protrusion (starting to lift down) during flow path switching in the tenth embodiment. FIG. 110 is an enlarged conceptual diagram showing the ground contact portion of FIG. 109 according to the tenth embodiment. FIG. 23 is an image diagram illustrating the relationship between the engaging structure and the engaged structure during flow path switching (during lift-down) in the tenth embodiment. FIG. 23 is an image diagram illustrating the relationship between the engaging structure and the engaged structure before the flow path switching is completed (before the lift-down is completed) in the tenth embodiment. FIG. 23 is an image diagram illustrating the relationship between the engaging structure and the engaged structure when flow path switching is completed (when lift-down is completed) in the tenth embodiment. FIG. 108 is an image diagram similar to FIG. 107 showing the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up) in the eleventh embodiment. FIG. 115 is an enlarged conceptual diagram showing the ground contact portion in FIG. 114 according to the eleventh embodiment.

Below, several embodiments of the flow path switching device will be described in detail with reference to the drawings.

First Embodiment
First, the first embodiment will be described in detail with reference to FIGS.

[Outline of flow path switching device]
FIG. 1 shows a perspective view of the flow path switching device 1 of this embodiment. FIG. 2 shows a front view of the flow path switching device 1. FIG. 3 shows a plan view of the flow path switching device 1. FIG. 4 shows a bottom view of the flow path switching device 1. FIG. 5 shows an exploded perspective view of the flow path switching device 1. FIG. 6 shows a cross-sectional view of the flow path switching device 1 taken along line A-A in FIG. 3. As shown in FIGS. 1 to 6, the flow path switching device 1 includes a housing 2, a valve body portion 3 arranged inside the housing 2, and a drive portion 4 that drives the valve body portion 3.

[About housing]
The housing 2 is formed by fastening an upper housing 11 and a lower housing 12 with a plurality of screws 6. The housing 2 includes an inlet flow path 20 through which a fluid flows in and an outlet flow path 30 through which the fluid flows out. Here, the flow path switching device 1 is configured as an eight-way valve, for example, and the housing 2 has four inlet flow paths 20 and four outlet flow paths 30. The four inlet flow paths 20 are provided in the upper housing 11 with a first inlet flow path 21, a second inlet flow path 22, a third inlet flow path 23, and a fourth inlet flow path 24. The lower housing 12 is provided with four outlet flow paths 30, including a first outlet flow path 31, a second outlet flow path 32, a third outlet flow path 33, and a fourth outlet flow path 34. The inlet flow paths 20 and the outlet flow paths 30 correspond to an example of a "communication path" provided in a "housing" of the disclosed technology. In this embodiment, the housing 2 is formed, for example, from resin.

[About the valve body]
5 and 6 , the valve body 3 includes a fixed disk 13 that does not rotate in the housing 2, a rotating disk 14 that is stacked on the fixed disk 13 and rotates relative to the fixed disk 13, and a rotating shaft 15 for rotating the rotating disk 14. The rotating disk 14 and the fixed disk 13 are stacked in the axial direction X. The rotating disk 14 corresponds to an example of a "drive disk" in the technology disclosed herein. The rotating disk 14 and the fixed disk 13 are formed, for example, from resin.

[About the rotating disc]
FIG. 7 shows a plan view of the rotating disk 14. As shown in FIGS. 6 and 7 , the rotating disk 14 is housed inside the housing 2. The rotating disk 14 is formed in a thick, circular plate shape and includes four rotation communication passages 40 that penetrate in the axial direction X. The four rotation communication passages 40 include a first rotation communication passage 41, a second rotation communication passage 42, a third rotation communication passage 43, and a fourth rotation communication passage 44. These rotation communication passages 40 are formed as slightly curved elongated holes in a plan view. These rotation communication passages 40 correspond to an example of a "communication passage" provided in a "drive disk" of the technology disclosed herein. A through hole 14a, through which the rotating shaft 15 penetrates, is formed in the center of the rotating disk 14. This through hole 14a has a cross-sectional shape (oval shape) larger than the outer diameter of the rotating shaft 15.

[About the rotation axis]
FIG. 8 shows an exploded perspective view of the upper housing 11 and the rotating shaft 15. In this embodiment, the rotating shaft 15 is made of resin. The rotating shaft 15 penetrates the upper housing 11 and the rotating disk 14, and is connected to the fixed disk 13 and the rotating disk 14 at one end in the axial direction X (the lower end in FIGS. 5 and 6 ). The other end in the axial direction X (the upper end in FIGS. 5 and 6 ) is connected to the drive unit 4. As shown in FIG. 8 , the other end of the rotating shaft 15 extends upward through a through-hole 11 a formed in the upper housing 11 and is connected to the drive unit 4. As shown in FIG. 6 , a lip seal 26 is provided between the upper housing 11 and the rotating shaft 15. The rotating shaft 15 may also be made of metal.

In this embodiment, the rotating disk 14 and the rotating shaft 15 are connected so as to be movable relative to each other in the rotational direction and the axial direction. That is, as shown in Figures 5 to 8, one end of the rotating shaft 15 (the lower end side in Figures 5 and 6) has a cross-sectional shape (oval) similar to the through-hole 14a of the rotating disk 14, but has a smaller cross-sectional shape than the through-hole 14a. That is, the connection between the rotating shaft 15 and the rotating disk 14 (the through-hole 14a and the corresponding lower portion of the rotating shaft 15) has a gap 28 in the rotational direction (see Figures 13 to 20 described below). The rotating shaft 15 is connected to the through-hole 14a so as to be movable relative to each other in the rotational direction and the axial direction. The rotating shaft 15 is assembled into the through-hole 14a of the rotating disk 14 so that its central axis coincides with the central axis of the disk 14. When the rotating shaft 15 receives driving force from the drive unit 4 and rotates, it spins freely in the through-hole 14a by the gap 28, and then engages with the inner wall of the through-hole 14a, rotating integrally with the rotating disk 14.

[About fixed disks]
FIG. 9 shows a perspective view of the fixed disk 13. As shown in FIG. 6, the fixed disk 13 is housed inside the lower housing 12. As shown in FIGS. 5, 6, and 9, the fixed disk 13 includes a disk portion 13a and a plurality of tubular portions 13b extending downward from the disk portion 13a. The disk portion 13a is formed in a disk shape and includes four fixed communication passages 50 that penetrate in the axial direction. As shown in FIGS. 5 and 8, the four fixed communication passages 50 include a first fixed communication passage 51, a second fixed communication passage 52, a third fixed communication passage 53, and a fourth fixed communication passage 54. The fixed communication passages 50 correspond to an example of a "communication passage" provided in a "fixed disk" of the technology disclosed herein.

The four cylindrical portions 13b of the fixed disk 13 are formed integrally with the disc portion 13a, and their interiors form fixed communication passages 50. Each cylindrical portion 13b is arranged to communicate with one of the outflow passages 30. A spring 16 is provided between the fixed disk 13 and the lower housing 12 to urge the fixed disk 13 toward the rotating disk 14. The spring 16 is arranged in the center of the lower surface 13c of the fixed disk 13 so as to be surrounded by the multiple cylindrical portions 13b. In addition, a lip seal 36 is provided between each cylindrical portion 13b and the lower housing 12 to ensure the sealing of the fixed communication passages 50.

[About the drive unit]
The drive unit 4 includes a motor and a speed reducer (not shown) for applying a rotational driving force to the rotary shaft 15. The flow path switching device 1 rotates the rotary disk 14 via the rotary shaft 15 using the drive unit 4, and switches the fluid flow path among several patterns by changing the combination of communication between the four rotary communication paths 40, the four inflow paths 20, and the four fixed communication paths 50. Here, a description of switching the flow path patterns will be omitted.

[Regarding sealing materials]
In this embodiment, seal members 17 and 18 are provided in the flow paths to prevent fluid leakage between the housing 2, the fixed disk 13, and the rotating disk 14. As shown in FIGS. 5 to 7 , the seal members 17 and 18 are provided on the rotating disk 14. That is, the seal members 17 and 18 are provided on the upper and lower end faces 14b and 14c of the rotating disk 14 so as to protrude from the upper and lower end faces 14b and 14c and surround the openings of the rotation communicating passages 40. In FIG. 6 , four upper seal members 17 are provided on the upper end face 14b of the rotating disk 14 corresponding to the four rotation communicating passages 40, and four lower seal members 18 are provided on the lower end face 14c of the rotating disk 14 corresponding to the four rotation communicating passages 40. Both the upper and lower seal members 17 and 18 are made of fluororesin (e.g., Teflon (registered trademark)). Alternatively, the upper and lower seal members 17 and 18 may be made of rubber to which a fluororesin is attached. The upper and lower seal members 17 and 18 may be made of rubber only.

In this embodiment, the seal members 17, 18 protruding from the upper and lower end faces 14b, 14c of the rotating disk 14 contact the inner surface of the upper housing 11 and the upper surface 13d of the fixed disk 13. Therefore, when the rotating disk 14 rotates, a large sliding resistance occurs between the seal members 17, 18 and the upper housing 11 and fixed disk 13. The sliding resistance is particularly large when the rotating disk 14 begins to rotate. To overcome this sliding resistance, it is possible to increase the output of the drive unit 4. However, this would increase the size of the drive unit 4 and its manufacturing costs. Therefore, in this embodiment, to solve the above problem, the flow path switching device 1 is provided with a sliding resistance reduction structure that reduces the sliding resistance of the seal members 17, 18.

[Sliding resistance reduction structure]
That is, in this embodiment, as shown in Figures 5, 6 and 8, the tip end portion 15a (lower end portion in the figures) of the rotating shaft 15 is provided so as to be able to abut and engage with the fixed disk 13. The tip end portion 15a is provided with an engagement structure K1 (see Figure 8) for the fixed disk 13. The fixed disk 13 is configured so as to be able to move back and forth in the axial direction X by the tip end portion 15a of the rotating shaft 15 abutting and engaging with it as it rotates. An engaged structure K2 (see Figure 9) with which the engaging structure K1 of the rotating shaft 15 engages is provided in the center of the upper surface of the fixed disk 13. The sliding resistance reducing structure is made up of the engaging structure K1 and the engaged structure K2.

Figure 10 shows an enlarged view of the engagement structure K2 of the fixed disk 13 shown in Figure 9. Figure 11 shows a front view of the rotating shaft 15. Figure 12 shows a perspective view of the engagement structure K1 (tip portion 15a) surrounded by the dashed-dotted circle in Figure 11. As shown in Figures 11 and 12, the tip surface (lower end surface) of the tip portion 15a of the rotating shaft 15 has multiple (four in this embodiment) protrusions (shaft convex portions) 15b arranged circumferentially along the outer periphery and forming a downwardly protruding mountain shape. These shaft convex portions 15b are alternately arranged at equal angular intervals. Each shaft convex portion 15b has a shape that converges toward its apex. Between adjacent shaft convex portions 15b, multiple (four in this embodiment) shaft concave portions 15c are arranged at equal angular intervals. These multiple shaft convex portions 15b and shaft concave portions 15c form the engagement structure K1 of the rotating shaft 15.

On the other hand, at the center of the upper surface 13d of the fixed disk 13, where the tip 15a of the rotating shaft 15 abuts and engages, as shown in FIG. 10, multiple grooves (disk recesses) 13e are formed in an annular, radial pattern at equal angular intervals. The shaft protrusions 15b abut and engage with the grooves as the rotating shaft 15 rotates. Disk protrusions 13g are arranged at equal angular intervals between adjacent disk recesses 13e. These multiple disk recesses 13e and disk protrusions 13g are arranged in a recess 13f that is circular in plan view and formed at the center of the upper surface 13d of the fixed disk 13. The engaged structure K2 of the fixed disk 13 is formed by these multiple disk recesses 13e and disk protrusions 13g.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 1 of this embodiment described above, the valve body portion 3 provided inside the housing 2 includes a vertically stacked fixed disk 13 and rotary disk 14, and a rotary shaft 15. Because the valve body portion 3 has a vertically stacked disk structure, complex flow path switching is possible with a small number of components. Furthermore, since flow paths can be switched simply by rotating the rotary disk 14 to change the position of the rotary communicating passage 40, there is no need to provide additional components for switching flow paths. Therefore, various flow path switching can be easily performed while miniaturizing the flow path switching device 1.

In this embodiment, the shaft protrusions 15b on the tip 15a of the rotating shaft 15 engage with and disengage from the multiple disk recesses 13e of the fixed disk 13 as the rotating shaft 15 rotates. The fixed disk 13 is biased by the spring 16 toward the tip 15a of the rotating shaft 15. As a result, when each shaft protrusion 15b moves from a misaligned state to a disk recess 13e, it engages with the corresponding disk recess 13e, causing the fixed disk 13 to be pushed upward toward the rotating disk 14 by the biasing force of the spring 16, and the fixed disk 13 contacts the lower seal member 18. Meanwhile, each shaft protrusion 15b disengages from the corresponding disk recess 13e and rides onto the disk protrusion 13g between the disk recesses 13e. This pushes the fixed disk 13 downward away from the rotating disk 14 against the biasing force of the spring 16, causing the fixed disk 13 to separate from the lower seal member 18.

Here, Figures 13 to 20 show, in stages, the operation of the sliding resistance reduction structure when the flow path switching device 1 transitions from one flow path switching state to another, and the operation of the rotating shaft 15, rotating disk 14, and fixed disk 13 when the rotating shaft 15 rotates and the rotating disk 14 rotates.

Figure 13 is a simplified cross-sectional view showing the upper housing 11, rotating disk 14, fixed disk 13, rotating shaft 15, etc. in a state before operation. Figure 14 shows the rotating disk 14 and rotating shaft 15 in a cross-sectional view taken along line B-B in Figure 13. Figures 13 and 14 show a state in which both the rotating disk 14 and rotating shaft 15 are stationary, with the upper and lower seal members 17, 18 abutting against the upper housing 11 and fixed disk 13, respectively.

Figure 15 is a simplified cross-sectional view showing the initial state of operation of the upper housing 11, rotating disk 14, fixed disk 13, and rotating shaft 15, with only the rotating shaft 15 starting to rotate. Figure 16 is a cross-sectional view of the rotating disk 14 and rotating shaft 15 taken along line C-C in Figure 15. Figures 15 and 16 show the state in which only the rotating shaft 15 rotates a predetermined angle within the through-hole 14a, causing the tip 15a of the rotating shaft 15 to press down on the fixed disk 13 due to the abutment between the shaft protrusion 15b and the disk recess 13e. At this time, the shaft protrusion 15b disengages from the disk recess 13e and rides onto the disk protrusion 13g between the disk recesses 13e, pushing down the fixed disk 13 against the biasing force of the spring 16, causing the upper seal member 17 to separate from the upper housing 11, and the lower seal member 18 to separate from the fixed disk 13.

Figure 17 is a cross-sectional view showing the operating state of the upper housing 11, rotating disk 14, fixed disk 13, and rotating shaft 15 when the rotating shaft 15 rotates further. Figure 18 is a cross-sectional view of the rotating disk 14 and rotating shaft 15 taken along line D-D in Figure 17. In Figures 17 and 18, the rotating shaft 15 rotates a predetermined angle further, causing the rotating disk 14 to rotate together with the rotation communication passage 40. At this time, the rotating disk 14 rotates after the fixed disk 13 is pressed down. Furthermore, because the gap between the upper housing 11 and fixed disk 13 and the gap between the rotating disk 14 and fixed disk 13 are both widened, the sliding resistance of the upper seal member 17 and lower seal member 18 when the rotating disk 14 rotates is reduced, and sliding wear of both the upper and lower seal members 17, 18 is also reduced.

Figure 19 is a simplified cross-sectional view showing the state of the upper housing 11, rotating disk 14, fixed disk 13, rotating shaft 15, etc., after the rotating shaft 15 and rotating disk 14 have further rotated. Figure 20 is a cross-sectional view of the rotating disk 14 and rotating shaft 15 taken along line E-E in Figure 19. In Figures 19 and 20, the rotating shaft 15 rotates a further predetermined angle, causing the rotating disk 14 to rotate a further predetermined angle together with the rotation communication passage 40. At this time, the shaft protrusions 15b of the rotating shaft 15 fit into the disk recesses 13e of the fixed disk 13, pushing the fixed disk 13 up by the biasing force of the spring 16, causing the upper seal member 17 to contact the upper housing 11 and the lower seal member 18 to contact the rotating disk 14.

According to the configuration of this embodiment, as described above, the rotating disk 14 rotates relative to the fixed disk 13 as the rotating shaft 15 rotates. At this time, the sliding resistance of the lower seal member 18 between the fixed disk 13 and the rotating disk 14 is reduced due to the rotation of the rotating disk 14. That is, according to the configuration described above, the tip 15a of the rotating shaft 15 is configured to be able to abut and engage with the fixed disk 13, and the fixed disk 13 is configured to be able to move back and forth in the axial direction as the tip 15a of the rotating shaft 15 abuts and engages with it as it rotates. Therefore, when the rotating disk 14 rotates due to the rotation of the rotating shaft 15, the fixed disk 13 moves back and forth in the axial direction X, widening the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14. This reduces the surface pressure applied to the upper seal member 17 and the lower seal member 18 between the upper housing 11 and the rotating disk 14 and between the fixed disk 13 and the rotating disk 14, thereby reducing the sliding resistance of each seal member 17, 18. This prevents the seal members 17 and 18 from coming loose due to sliding wear or snagging when the rotating disk 14 rotates.

Furthermore, according to the configuration of this embodiment, the rotating disk 14 and the rotating shaft 15 are connected so as to be able to move relative to each other in the rotational direction and the axial direction X. Therefore, when the rotating disk 14 rotates and surface pressure is applied to each of the seal members 17, 18, the rotating disk 14 moves in the rotational direction and the axial direction X within the gap between the housing 2 and the fixed disk 13, and is positioned in a position that balances the reaction force of each of the seal members 17, 18. This further reduces the surface pressure applied to each of the seal members 17, 18 when the rotating disk 14 rotates, improving the durability of each of the seal members 17, 18.

In this embodiment, seal members 17, 18 are provided between the housing 2 (upper housing 11) and the rotating disk 14, and between the rotating disk 14 and the fixed disk 13 in the axial direction X of the flow path switching device 1. Elastic seal members 17, 18 are provided between the upper housing 11 and the rotating disk 14, and between the rotating disk 14 and the fixed disk 13 in the axial direction X. This allows the rotating disk 14 to be supported in a floating state by the upper and lower seal members 17, 18. As a result, when the rotating disk 14 rotates, the floating effect reduces sliding resistance due to the application of fluid pressure. This prevents uneven wear of the seal members 17, 18, which ensure the sealing of the rotary communication passage 40 and the fixed communication passage 50. This ensures that the seal members 17, 18 reliably prevent fluid leakage from the rotary communication passage 40 and the fixed communication passage 50. This ensures the sealing of the flow paths formed by the inlet flow path 20, the rotary communication passage 40, and the fixed communication passage 50.

Furthermore, with the configuration of this embodiment, the sealing members 17, 18 can also be used as elastic members to maintain the orientation of the fixed disk 13 and the rotating disk 14. This eliminates the need for a separate elastic member, suppresses an increase in the number of parts, and also enables the flow path switching device 1 to be made more compact. Furthermore, because the axial direction X of the fixed disk 13 and the rotating disk 14 and the sealing direction of the sealing members 17, 18 are the same, sealing performance can be ensured even if a misalignment of the central axis occurs when the rotating disk 14 is rotated.

Furthermore, according to the configuration of this embodiment, the upper seal member 17, provided between the upper housing 11 and the rotating disk 14, and the lower seal member 18, provided between the rotating disk 14 and the fixed disk 13, are positioned at the same radial position on the rotating disk 14. Therefore, the rotation communication passage 40 is sealed by the seal members 17, 18 at the same position on both the upper end surface 14b and the lower end surface 14c of the rotating disk 14, and the area on which fluid pressure acts is the same at both the upper and lower end surfaces 14b, 14c of the rotating disk 14. As a result, the fluid pressure acting on the upper end surface 14b and the lower end surface 14c is canceled, and only the biasing force of the spring 16 acts on the rotating disk 14, maintaining the orientation of the rotating disk 14. This reduces the sliding resistance between the rotating disk 14 and the fixed disk 13 when the rotating disk 14 rotates. As a result, the power of the drive unit 4, which drives the rotating disk 14, can be reduced, thereby reducing the power consumption of the drive unit 4. In addition, the load applied from the rotating disk 14 to each seal member 17, 18 is reduced, improving the reliability of the sealing performance of each seal member 17, 18.

Furthermore, with the configuration of this embodiment, at least a portion of the cylindrical portion 13b of the fixed disk 13 is inserted inside the outflow passage 30. This prevents circumferential displacement of the fixed disk 13 due to the rotational drive of the rotating disk 14. Furthermore, because the direction in which the rotating disk 14 may become misaligned (i.e., the left-right direction intersecting the axial direction X) differs from the sealing direction of each sealing member 17, 18 (i.e., the axial direction X), the sealing performance of each sealing member 17, 18 is maintained even if the rotating disk 14 becomes misaligned.

In this embodiment, the upper seal member 17, located between the upper housing 11 and the rotating disk 14, and the lower seal member 18, located between the rotating disk 14 and the fixed disk 13, are positioned at the same radial position on the rotating disk 14. Therefore, even if the rotating disk 14 tilts due to fluid pressure or the like, the repulsive force of each seal member 17, 18 can return the rotating disk 14 to a horizontal position. Furthermore, each seal member 17, 18 applies uniform surface pressure to the upper housing 11 and the fixed disk 13 in the circumferential direction while sealing them. This reduces the sliding resistance of each seal member 17, 18 and causes uniform wear. As a result, the rotating disk 14 can be maintained in a horizontal position even after years of use.

In this embodiment, the connection between the rotating shaft 15 and the rotating disk 14 (the portion where the rotating shaft 15 and the through-hole 14a correspond) has a gap 28 in the rotational direction. Therefore, when the rotating shaft 15 is rotated, the rotating shaft 15 rotates freely by the gap 28 at the connection. Therefore, even when the rotating shaft 15 is rotated, the rotating disk 14 does not rotate, and the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 can be set to a widened state. As a result, a section can be set in which the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 is widened before the rotating shaft 15 is driven to rotate.

Second Embodiment
Next, the second embodiment will be described in detail with reference to Figures 21 to 39(D). In the following description, the same components as those in the first embodiment will be denoted by the same reference numerals and will not be described again, and the following description will focus on the differences.

[Sliding resistance reduction structure]
The flow path switching device 1 of this embodiment has the same external appearance and internal basic structure as the first embodiment, but differs from the first embodiment in the configuration of the above-mentioned "sliding resistance reduction structure." Figure 21 is a plan view of the flow path switching device 1 of this embodiment with the upper housing 11 and drive unit 4 removed. Figure 22 is an enlarged plan view of the through hole 14a and the rotating shaft 15 (encircled by the dashed line) in Figure 21. Figure 23 is a perspective view of the rotating shaft 15 of this embodiment. Figure 24 is an enlarged perspective view of the engagement structure K1 at the tip of the rotating shaft 15 shown in Figure 23. Figure 25 is a plan view of the fixed disk 13 of this embodiment. Figure 26 is an enlarged perspective view of the engaged structure K2 of the fixed disk 13 shown in Figure 25.

In this embodiment, the basic configuration of the fixed disk 13, rotating disk 14, rotating shaft 15, upper seal member 17, and lower seal member 18 is the same as that of the first embodiment, but as shown in Figures 21 to 26, it differs from the first embodiment in the cross-sectional shape of the through hole 14a of the rotating disk 14, the shape of the portion of the rotating shaft 15 that engages with the through hole 14a, and the configuration of the engaging structure K1 of the rotating shaft 15 and the engaged structure K2 of the fixed disk 13.

That is, as shown in Figure 22, the cross-sectional shape of the through hole 14a is a butterfly shape with two sectors arranged rotationally symmetrically around the axis. The cross-sectional shape of the portion of the rotating shaft 15 that engages with the through hole 14a is a two-sided shape (oval) that allows it to rotate within the through hole 14a. In this embodiment, the connection portion between the rotating shaft 15 and the rotating disk 14 (the portion where the rotating shaft 15 and through hole 14a correspond) has a predetermined gap 28 between the rotating shaft 15 and the inner wall of the through hole 14a. When the rotating shaft 15 receives driving force from the drive unit 4 and rotates, it rotates freely in the through hole 14a by the amount of the gap 28, and then engages with the inner wall of the through hole 14a to rotate integrally with the rotating disk 14.

As shown in Figures 23 and 24, the engagement structure K1 provided at the tip of the rotating shaft 15 has a shape substantially identical to that of the first embodiment, and includes four recesses (shaft recesses) 15c and four protrusions (shaft protrusions) 15b aligned in the circumferential direction. The shaft protrusions 15b are spaced at equal angular intervals (90°), with the shaft recesses 15c formed between the shaft protrusions 15b. Each shaft recess 15c and each shaft protrusion 15b includes a side surface 15d that slopes in the circumferential direction (arrangement direction). In this embodiment, the apex 15e of each shaft protrusion 15b is formed as a convex curved surface that protrudes outward, and includes side surfaces 15d that slope to both sides of the apex 15e. The inclination angles of both side surfaces 15d are set to the same angle. These side surfaces 15d are also the side surfaces of the shaft recess 15c. Furthermore, the bottom of each shaft recess 15c is flat.

On the other hand, as shown in Figures 25 and 26, the engagement structure K2 provided in the center of the upper surface 13d of the fixed disk 13 includes four convex portions (disk convex portions) 13g and four concave portions (disk concave portions) 13e that can abut and engage with the shaft concave portions 15c and shaft convex portions 15b as the rotating shaft 15 rotates. The disk convex portions 13g are spaced at equal angular intervals (90°), and the spaces between the disk convex portions 13g form disk concave portions 13e. In this embodiment, each disk convex portion 13g includes side portions 13i that slope circumferentially (in the arrangement direction) on both sides of the top portion 13h. The inclination angles of both side portions 13i are set to the same angle. These side portions 13i are also side portions of the disk concave portion 13e. Furthermore, the bottom of each disk concave portion 13e is flat.

[Switching flow path patterns]
The flow path switching device 1 of this embodiment has the above-described configuration, and is therefore capable of switching the flow path of the fluid among four patterns. Figures 27(A) to 39(D) show operational diagrams related to the switching of the flow path patterns.

First, Figures 27(A) to 27(D) show the "initial state" of the flow path switching device 1 of this embodiment, with Figure 27(A) being an illustration showing the engagement relationship between the through-hole 14a of the rotating disk 14 and the rotating shaft 15. Each of Figures 28 to 39 (A), described below, is an illustration similar to Figure 27(A). Figure 27(B) is an illustration showing the change in lift (push-up) of the rotating shaft 15 relative to the rotation angle (rotation shaft angle) of the rotating shaft 15. In Figure 27(B), the thick peaks and valleys correspond to the disk convex portion 13g and the disk concave portion 13e, respectively, and the black dots correspond to the position of the shaft convex portion 15b (the same applies to similar figures described below). Each of Figures 28 to 39 (B), described below, is an illustration similar to Figure 27(B). Figure 27(C) is a plan view showing the rotational position of the through-hole 14a and the rotating shaft 15, and the positional relationship between the disk protrusion 13g, disk recess 13e, and shaft protrusion 15b. Each of Figures 28 to 39 (C), which will be described later, is a plan view equivalent to Figure 27(C). Figure 27(D) is a plan view equivalent to Figure 21, showing the rotational position of the rotating disk 14 and rotation communicating passage 40. In Figure 27(D), the reference line L1, shown by a thick dashed line, indicates the reference position on the rotating disk 14 (the same applies to similar figures described later). Each of Figures 28 to 39 (D), which will be described later, is a plan view equivalent to Figure 27(D).

In this "initial state," as shown in Figure 27(A), the rotating shaft 15 engages with one inner wall of the through-hole 14a, and as shown in Figure 27(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 27(C), the shaft protrusion 15b rests on the disk recess 13e. Furthermore, the rotating disk 14 and rotation communicating passage 40 are positioned as shown in Figure 27(D). At this time, the first rotation communicating passage 41 communicates with the second inlet flow path 22 and the second fixed communicating passage 52, the second rotation communicating passage 42 communicates with the third inlet flow path 23 and the third fixed communicating passage 53, the third rotation communicating passage 43 communicates with the fourth inlet flow path 24 and the fourth fixed communicating passage 54, and the fourth rotation communicating passage 44 communicates with the first inlet flow path 21 and the first fixed communicating passage 51. The rotation angle of the rotating disk 14 (disk rotation angle) at this time is defined as "0°," and this flow path switching state is defined as "Pattern A."

Next, we will explain the changes from the "initial state" one by one. Figures 28(A) to 28(D) show the "45° rotated state" in which the rotating shaft 15 has rotated "45°" clockwise from the "initial state." In this state, as shown in Figure 28(A), the rotating shaft 15 rotates 45° clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and as shown in Figure 28(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 28(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 28(D), the disk rotation angle remains at "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as the "initial state."

As described above, in this embodiment, when the tip of the rotating shaft 15 transitions from an engaged state to an abutting state with the fixed disk 13, i.e., when the shaft protrusion 15b moves from the disk recess 13e onto the disk protrusion 13g, the "idling angle" at which the rotating shaft 15 rotates idly in the clockwise direction is set to "45°." Also, in this embodiment, in the "initial state" shown in Figure 27(A), the rotating shaft 15 is a "one-side idling type" that can only rotate idly in the clockwise direction.

Next, Figures 29(A) to 29(D) show the "90° rotated state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "45° rotated state." In this state, as shown in Figure 29(A), the rotating shaft 15 rotates 45° clockwise together with the rotating disc 14, and as shown in Figure 29(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 29(C), the shaft protrusion 15b rests on the disc recess 13e. Furthermore, as shown in Figure 29(D), the rotation communicating passage 40 has rotated 45° clockwise. In this "90° rotation state," the first rotation communication passage 41 communicates with the second inflow passage 22 and the third fixed communication passage 53, the second rotation communication passage 42 communicates with the third inflow passage 23 and the fourth fixed communication passage 54, the third rotation communication passage 43 communicates with the fourth inflow passage 24 and the first fixed communication passage 51, and the fourth rotation communication passage 44 communicates with the first inflow passage 21 and the second fixed communication passage 52. The disc rotation angle at this time is "45°," and this flow passage switching state is defined as "Pattern B." In other words, between the "45° rotation state" and the "90° rotation state," the rotation shaft 15 is lifted down and the flow passages are switched simultaneously.

As described above, in this embodiment, the "switching angle" at which the rotary disk 14 is rotated to switch the flow paths of the flow path switching device 1 is set to "45°." In other words, in this embodiment, the clockwise "idle rotation angle" of the rotating shaft 15 and the "switching angle" of the rotary disk 14 for switching the flow paths are set to the same "45°."

Next, Figures 30(A) to 30(D) show the "135° rotation state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "90° rotation state." In this state, as shown in Figure 30(A), the rotating shaft 15 rotates 45° clockwise together with the rotating disk 14, and as shown in Figure 30(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 30(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 30(D), the rotation communicating passage 40 has rotated 45° clockwise. In this "135° rotation state," the first rotation communication passage 41 communicates with the third inflow passage 23 and the third fixed communication passage 53, the second rotation communication passage 42 communicates with the fourth inflow passage 24 and the fourth fixed communication passage 54, the third rotation communication passage 43 communicates with the first inflow passage 21 and the first fixed communication passage 51, and the fourth rotation communication passage 44 communicates with the second inflow passage 22 and the second fixed communication passage 52. The disc rotation angle at this time is "90°," and this flow path switching state is defined as "Pattern C." In other words, between the "90° rotation state" and the "135° rotation state," the rotation shaft 15 lifts up and the flow paths switch simultaneously.

Next, Figures 31(A) to 31(D) show the "return 90° rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "135° rotation state." In this state, as shown in Figure 31(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, and as shown in Figure 31(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 31(C), the shaft protrusion 15b rests on the disc recess 13e. Furthermore, as shown in Figure 31(D), the rotation communicating passage 40 remains in the same position as in the "135° rotation state," and the disc rotation angle remains at 90°. The flow path switching state at this time is "Pattern C," the same as in the "135° rotation state."

As described above, in this embodiment, the "idle rotation angle" at which the rotating shaft 15 rotates counterclockwise when the shaft protrusion 15b moves from the disk protrusion 13g onto the disk recess 13e is also set to "45°." In other words, in this embodiment, the "idle rotation angle" of the rotating shaft 15 in the counterclockwise direction and the "switching angle" of the rotating disk 14 for switching the flow path are also set to the same "45°."

Next, Figures 32(A) to 32(D) show the "135° re-rotation state" in which the rotating shaft 15 has rotated 45° clockwise from the "90° return rotation state." In this state, as shown in Figure 32(A), the rotating shaft 15 rotates 45° clockwise and engages with the other inner wall of the through-hole 14a, and as shown in Figure 32(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 32(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 32(D), the rotation communicating passage 40 remains in the same position as in the "90° return rotation state," and the disk rotation angle remains at 90°. The flow path switching state at this time is "Pattern C."

Next, Figures 33(A) to 33(D) show the "180° rotated state" in which the rotating shaft 15 has rotated "45°" clockwise from the "135° re-rotated state." In this state, as shown in Figure 33(A), the rotating shaft 15 rotates "45°" clockwise together with the rotating disc 14, and as shown in Figure 33(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 33(C), the shaft protrusion 15b rides down on the disc recess 13e. Furthermore, as shown in Figure 33(D), the rotation communicating passage 40 has rotated another "45°" clockwise. In this "180° rotation state," the first rotation communication passage 41 communicates with the third inflow passage 23 and the fourth fixed communication passage 54, the second rotation communication passage 42 communicates with the fourth inflow passage 24 and the first fixed communication passage 51, the third rotation communication passage 43 communicates with the first inflow passage 21 and the second fixed communication passage 52, and the fourth rotation communication passage 44 communicates with the second inflow passage 22 and the third fixed communication passage 53. The disc rotation angle at this time is "135°," and this flow path switching state is defined as "Pattern D." In other words, between the "135° rotation state" and the "180° rotation state," the rotation shaft 15 is lifted down and the flow paths are switched simultaneously.

Next, Figures 34(A) to 34(D) show the "return 135° rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "180° rotation state." In this state, as shown in Figure 34(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, and as shown in Figure 34(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 34(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 34(D), the rotation communicating passage 40 remains in the same position as in the "180° rotation state," and the disk rotation angle remains at 135°. The flow path switching state at this time is "Pattern D," the same as in the "180° rotation state."

Next, Figures 35(A) to 35(D) show the "90° Return Rotation State" in which the rotating shaft 15 has rotated 45° counterclockwise from the "135° Return Rotation State." In this state, as shown in Figure 35(A), the rotating shaft 15 rotates 45° counterclockwise together with the rotating disk 14, and as shown in Figure 35(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 35(C), the shaft protrusion 15b rests on the disk recess 13e. Furthermore, as shown in Figure 35(D), the rotation communication passage 40 is in the same position as in the "135° Re-Rotation State," and the disk rotation angle is 90°. The flow path switching state at this time is "Pattern C," the same as the "135° Re-Rotation State." In other words, between the "135° Return Rotation State" and the "90° Return Rotation State," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

Next, Figures 36(A) to 36(D) show the "45° Return Rotation State" in which the rotating shaft 15 has rotated a further 45° counterclockwise from the "90° Return Rotation State." In this state, as shown in Figure 36(A), the rotating shaft 15 rotates 45° counterclockwise together with the rotating disk 14, and as shown in Figure 36(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 36(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 36(D), the rotation communication passage 40 is in the same position as in the "90° Rotation State," and the disk rotation angle is 45°. The flow path switching state at this time is "Pattern B," the same as in the "90° Rotation State." In other words, between the "90° Return Rotation State" and the "45° Return Rotation State," the lifting up of the rotating shaft 15 and the flow path switching occur simultaneously.

Next, Figures 37(A) to 37(D) show the "re-90° rotation state" in which the rotating shaft 15 has rotated 45° clockwise from the "45° return rotation state." In this state, as shown in Figure 37(A), the rotating shaft 15 rotates 45° clockwise and engages with the other inner wall of the through-hole 14a, and as shown in Figure 37(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 37(C), the shaft protrusion 15b rests on the disc recess 13e. Furthermore, as shown in Figure 37(D), the rotation communicating passage 40 remains in the same position as in the "45° return rotation state," and the disc rotation angle remains at 45°. The flow path switching state at this time is "Pattern B," the same as in the "45° return rotation state."

Next, Figures 38(A) to 38(D) show the "return 45° rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "re-rotated 90° state." In this state, as shown in Figure 38(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, and as shown in Figure 38(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 38(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 38(D), the rotation communicating passage 40 remains in the same position as in the "re-rotated 90° state," and the disk rotation angle remains at 45°. The flow path switching state at this time is "pattern B."

Figures 39(A) to 39(D) show the "return initial state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "return 45° rotation state." In this state, as shown in Figure 39(A), the rotating shaft 15 rotates 45° counterclockwise together with the rotating disk 14, and as shown in Figure 39(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 39(C), the shaft protrusion 15b rests on the disk recess 13e. Furthermore, as shown in Figure 39(D), the rotation communication passage 40 has returned to the same position as in the "initial state," and the disk rotation angle is 0°. The flow path switching state at this time is "pattern A," the same as the "initial state." In other words, between the "return 45° rotation state" and the "return initial state," the lifting down of the rotating shaft 15 and the flow path switching occur simultaneously.

[Operation and effect of the flow path switching device]
The configuration of the flow path switching device 1 of this embodiment described above provides the following functions and effects in addition to the functions and effects of the first embodiment. That is, with the configuration of this flow path switching device 1, rotating the rotating shaft 15 provides two states: a state in which the shaft convex portion 15b abuts against the disk convex portion 13g (a convex-convex abutment state), and a state in which the shaft convex portion 15b and the shaft concave portion 15c engage with the disk concave portion 13e and the disk convex portion 13g (a convex-concave engagement state). In this convex-convex abutment state, the fixed disk 13 moves axially, widening the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14, thereby reducing the surface pressure applied to the upper seal member 17 and the lower seal member 18 between the upper housing 11 and the rotating disk 14 and between the fixed disk 13 and the rotating disk 14. In contrast, in the convex-concave engagement state, the fixed disk 13 moves axially, returning the upper housing 11 and the rotating disk 14 and the fixed disk 13 and the rotating disk 14 to their original gaps, and the surface pressure applied to the upper seal member 17 and the lower seal member 18 between the upper housing 11 and the rotating disk 14 and between the fixed disk 13 and the rotating disk 14 returns to its original state. When switching between the convex-concave abutment state and the convex-concave engagement state, the shaft convex portion 15b and the shaft concave portion 15c come into contact with the inclined side portions 13i, 15d of the disk concave portion 13e and the disk convex portion 13g, respectively. This allows for smooth switching between the convex-convex abutment state and the convex-concave engagement state.

According to the configuration of this embodiment, when the shaft protrusion 15b and the disk protrusion 13g are in contact, the top 15e of the shaft protrusion 15b is formed into a convex curved surface. Therefore, when the rotating shaft 15 is rotated from this state, the axial position of the rotating shaft 15 does not change suddenly. Furthermore, because the bottoms of the disk recess 13e and the shaft recess 15c are formed into a flat surface, the axial position of the rotating shaft 15 does not change suddenly when the rotating shaft 15 is rotated with the shaft protrusion 15b and the shaft recess 15c engaged with the disk recess 13e and the disk protrusion 13g. This further reduces sliding wear on the lower seal member 18.

According to the configuration of this embodiment, when the shaft protrusion 15b moves from the disk recess 13e onto the disk protrusion 13g, i.e., when the fixed disk 13 moves axially and the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 widens, the idle angle of the rotating shaft 15 and the switching angle of the rotating disk 14 when switching flow paths are set to the same angle (45°). Therefore, by rotating the rotating shaft 15 counterclockwise (in the opposite direction) through the switching angle and idle angle (45°), the rotational positions of the rotating shaft 15 and the rotating disk 14 can be returned to their original states. This allows the flow path switching operation when the rotating shaft 15 is rotated clockwise (in one direction) to coincide with the flow path switching operation when the rotating shaft 15 is rotated counterclockwise.

In this embodiment, as shown in Figures 29(A) to 29(D), 33(A) to 33(D), 35(A) to 35(D), and 39(A) to 39(D), when the rotating disk 14 rotates, the rotating shaft 15 lifts down (the fixed disk 13 and rotating disk 14 return to their original spacing). Therefore, when the flow path switches, the surface pressure applied to the seal members 17, 18 between the upper housing 11 and rotating disk 14 and between the fixed disk 13 and rotating disk 14 is reduced, preventing the seal members 17, 18 from coming off due to sliding wear or snagging. The same is true when the rotating shaft 15 lifts up (the spacing between the fixed disk 13 and rotating disk 14 widens) when the rotating disk 14 rotates, as shown in Figures 30(A) to 30(D) and 36(A) to 36(D).

In this embodiment, in a configuration where the flow path is "idle-spin type only" and can be switched between two patterns, the clockwise "idle angle" of the rotating shaft 15 and the flow path "switching angle" are set to the same "45°." Therefore, as shown in Figures 29(A) to 29(D), 33(A) to 33(D), 35(A) to 35(D), and 39(A) to 39(D), when switching the flow path, the rotating shaft 15 is lifted up, and then the flow path is switched and the rotating shaft 15 is lifted down simultaneously. This allows for a reduction in the drive torque of the rotating shaft 15 (drive torque of the drive unit 4), enabling the drive unit 4 (motor) to be made more compact.

In this embodiment, as in the first embodiment, a predetermined gap 28 is provided at the connection between the rotating shaft 15 and the rotating disk 14 (between the rotating shaft 15 and the inner wall of the through-hole 14a). When the rotating shaft 15 receives driving force from the drive unit 4 and rotates, it rotates freely in the through-hole 14a by the gap 28, and then engages with the inner wall of the through-hole 14a to rotate integrally with the rotating disk 14. Therefore, even when the rotating shaft 15 is rotated, the rotating disk 14 does not rotate, and the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 can be widened. As a result, the rotating disk 14 can be lifted up or down without rotating.

Let's now consider a case where there is no gap in the rotational direction at the connection between the rotating shaft and the rotating disk. For example, suppose the rotating disk is configured to rotate 45° to switch flow paths. In this case, when switching flow paths, the rotating shaft needs to be lifted up and down while the rotating disk is rotated 45°. In this case, the rotating shaft is rotated 22.5° to lift up the rotating shaft, and to increase the lift amount of the rotating shaft at that time, the driving torque of the rotating shaft needs to be increased. In other words, if the driving torque of the rotating shaft is not increased, the lift amount of the rotating shaft cannot be increased. As a result, the reduction in surface pressure of the sealing member during flow path switching is reduced. In contrast, in this embodiment, by providing a gap 28 in the rotational direction of the rotating shaft 15, i.e., by allowing the rotating shaft 15 to rotate freely, the lift amount of the rotating shaft 15 (the increase in the gap between the fixed disk 13 and the rotating disk 14) can be increased without significantly increasing the driving torque of the rotating shaft 15 (the driving torque of the drive unit 4).

Third Embodiment
Next, the third embodiment will be described in detail with reference to FIGS. 40(A) to 44(C).

The flow path switching device 1 of this embodiment is basically the same in appearance and internal structure as that of the first embodiment, but differs from the second embodiment in the configuration of the "sliding resistance reduction structure" described above, i.e., the engaging structure K1 and the engaged structure K2.

[Switching flow path patterns]
Due to the differences in configuration described above, the flow path switching device 1 of this embodiment is capable of switching the fluid flow path between two patterns. Figures 40(A) to 44(C) show operational diagrams related to switching the flow path pattern. The flow path switching device 1 of this embodiment is the same "one-side idling type" as the second embodiment.

First, Figures 40(A) to 40(C) show the "initial state" of the flow path switching device 1 of this embodiment, with Figure 40(A) being an image showing the engagement relationship between the through-hole 14a of the rotating disk 14 and the rotating shaft 15. Each of Figures 41 to 44 (A), which will be described later, is an image similar to Figure 40(A). Figure 40(B) is an image showing the change in lift of the rotating shaft 15 relative to the rotating shaft angle. Each of Figures 41 to 44 (B), which will be described later, is an image similar to Figure 40(B). Figure 40(C) is a plan view similar to Figure 21, showing the rotational positions of the rotating disk 14 and the rotation communicating passage 40. Each of Figures 41 to 44 (C), which will be described later, is a plan view similar to Figure 40(C).

In this "initial state," as shown in Figure 40(A), the rotating shaft 15 engages with one inner wall of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 40(B). The rotating disk 14 and rotation communication passage 40 are positioned as shown in Figure 40(C). The disk rotation angle at this time is "0°," and the flow path switching state is the same as "Pattern A" in the second embodiment.

Next, we will explain the changes from the "initial state" one by one. Figures 41(A) to 41(C) show the "45° rotated state" in which the rotating shaft 15 has rotated "45°" clockwise from the "initial state." In this state, as shown in Figure 41(A), the rotating shaft 15 rotates 45° clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and the shaft protrusion 15b rides up onto the disk protrusion 13g, lifting the rotating shaft 15 up as shown in Figure 41(B). Also, as shown in Figure 41(C), the disk rotation angle remains at "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as in the "initial state."

As mentioned above, in this embodiment, the "idling angle" at which the rotating shaft 15 rotates clockwise when the shaft protrusion 15b rides on the disk protrusion 13g is set to 45°.

Next, Figures 42(A) to 42(C) show the "90° rotation state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "45° rotation state." In this state, as shown in Figure 42(A), the rotating shaft 15 rotates 45° clockwise together with the rotating disc 14, and the shaft protrusion 15b rides down into the disc recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 42(B). Also, as shown in Figure 42(C), the disc rotation angle is 45°, and the flow path switching state of the rotation communication passage 40 is the same as "Pattern B" in the second embodiment. In other words, between the "45° rotation state" and the "90° rotation state," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

As mentioned above, in this embodiment, the clockwise "idle angle" of the rotating shaft 15 and the "switching angle" for switching the flow path are set to the same value of "45°."

Next, Figures 43(A) to 43(C) show the "return 45° rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "90° rotation state." In this state, as shown in Figure 43(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, causing the shaft protrusion 15b to ride up onto the disk protrusion 13g, lifting the rotating shaft 15 up as shown in Figure 43(B). Also, as shown in Figure 43(C), the disk rotation angle is 45°, and the flow path switching state of the rotation communicating passage 40 is "Pattern B," the same as in the "90° rotation state."

Figures 44(A) to 44(C) show the "return initial state" in which the rotating shaft 15 has rotated a further 45° counterclockwise from the "return 45° rotated state." In this state, as shown in Figure 44(A), the rotating shaft 15 rotates 45° counterclockwise together with the rotating disk 14, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 44(B). Also, as shown in Figure 44(C), the disk rotation angle is 0°, and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as the "initial state."

[Operation and effect of the flow path switching device]
The flow path switching device 1 of this embodiment described above differs in configuration from the second embodiment, which can switch the fluid flow path between four patterns, in that it can switch between two patterns, but it can achieve the same functions and effects as the second embodiment.

In this embodiment, as shown in Figures 42(A) to 42(C) and 44(A) to 44(C), when the rotating disk 14 rotates (when the flow path switches), the rotating shaft 15 lifts down (the fixed disk 13 and the upper housing 11 return to their original spacing). As a result, when the rotating disk 14 rotates, the surface pressure applied to each seal member 17, 18 between the fixed disk 13 and the upper housing 11 is reduced, which means that the seal members 17, 18 can be prevented from coming loose due to sliding wear or snagging.

In this embodiment, in a configuration where the flow path is "idle-spin type only" and can be switched between two patterns, the clockwise "idle angle" of the rotating shaft 15 and the flow path "switching angle" are set to the same "45°". Therefore, as shown in Figures 42(A) to 42(C) and 44(A) to 44(C), when switching the flow path, the rotating shaft 15 is lifted up, and then the flow path is switched and the rotating shaft 15 is lifted down simultaneously. This allows the drive torque of the rotating shaft 15 (drive torque of the drive unit 4) to be reduced, enabling the drive unit 4 (motor) to be made more compact.

Fourth Embodiment
Next, the fourth embodiment will be described in detail with reference to FIGS. 45(A) to 49(C).

The flow path switching device 1 of this embodiment differs from the third embodiment in the configuration of the "sliding resistance reduction structure" described above, i.e., the engaging structure K1 and the engaged structure K2.

[Switching flow path patterns]
The flow path switching device 1 of this embodiment, like the third embodiment, is capable of switching the fluid flow path between two patterns. Figures 45(A) to 49(C) show operation diagrams related to switching the flow path pattern. The flow path switching device 1 of this embodiment is of the "one-side idling type" as in the third embodiment.

First, Figures 45(A) to 45(C) show the "initial state" of the flow path switching device 1 of this embodiment, with Figure 45(A) being an illustration showing the engagement relationship between the through-hole 14a of the rotating disk 14 and the rotating shaft 15. Each of Figures 46 to 49 (A), described later, is an illustration similar to Figure 45(A). Figure 45(B) is an illustration showing the change in lift of the rotating shaft 15 relative to the rotating shaft angle. Each of Figures 46 to 49 (B), described later, is an illustration similar to Figure 45(B). Figure 45(C) is a plan view similar to Figure 21, showing the rotational positions of the rotating disk 14 and the rotation communicating passage 40. Each of Figures 46 to 49 (C), described later, is a plan view similar to Figure 45(C).

In this "initial state," as shown in Figure 45(A), the rotating shaft 15 engages with one inner wall of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to be lifted down as shown in Figure 45(B). The rotating disk 14 and rotation communication passage 40 are positioned as shown in Figure 45(C). The disk rotation angle at this time is "0°," and the flow path switching state is the same as "Pattern A" in the third embodiment.

Next, we will explain the changes from the "initial state" one by one. Figures 46(A) to 46(C) show the "22.5° rotation state" in which the rotating shaft 15 has rotated "22.5°" clockwise from the "initial state." In this state, as shown in Figure 46(A), the rotating shaft 15 rotates idly "22.5°" clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and the shaft protrusion 15b rides up onto the disk protrusion 13g, lifting the rotating shaft 15 up as shown in Figure 46(B). Also, as shown in Figure 46(C), the disk rotation angle is "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as the "initial state."

As described above, in this embodiment, the "idling angle" at which the rotating shaft 15 rotates clockwise when the shaft protrusion 15b rides on the disk protrusion 13g is set to 22.5°.

Next, Figures 47(A) to 47(C) show the "67.5° rotation state" in which the rotating shaft 15 has rotated "45°" clockwise from the "22.5° rotation state." In this state, as shown in Figure 47(A), the rotating shaft 15 rotates "45°" clockwise together with the rotating disc 14, and the shaft protrusion 15b rides down into the disc recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 47(B). Also, as shown in Figure 47(C), the disc rotation angle is "45°," and the flow path switching state of the rotation communication passage 40 is the same as "Pattern B" in the third embodiment. In other words, between the "22.5° rotation state" and the "67.5° rotation state," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

In this embodiment, the "switching angle" at which the rotary disk 14 is rotated to switch the flow path is set to "45°." In other words, in this embodiment, the "switching angle" for switching the flow path is set to an angle greater than the "idling angle" of the rotating shaft 15 in the clockwise direction.

Next, Figures 48(A) to 48(C) show the "45° return rotation state" in which the rotating shaft 15 has rotated counterclockwise by 22.5° from the "67.5° rotation state." In this state, as shown in Figure 48(A), the rotating shaft 15 rotates counterclockwise by 22.5° and engages with one inner wall of the through-hole 14a, and the shaft protrusion 15b begins to move toward the disk protrusion 13g, causing the rotating shaft 15 to lift up partway as shown in Figure 48(B). Furthermore, as shown in Figure 48(C), the disk rotation angle remains at 45°, and the flow path switching state of the rotation communicating passage 40 is "Pattern B," the same as in the "67.5° rotation state."

Figures 49(A) to 49(C) show the "return initial state" in which the rotating shaft 15 has rotated 45 degrees counterclockwise from the "return 45° rotation state." In this state, as shown in Figure 49(A), the rotating shaft 15 rotates 45 degrees counterclockwise together with the rotating disk 14, and the shaft protrusion 15b climbs over the disk protrusion 13g and slides down onto the disk recess 13e, causing the rotating shaft 15 to lift up and down as shown in Figure 49(B). Also, as shown in Figure 49(C), the disk rotation angle is 0°, and the flow path switching state of the rotation communication passage 40 is "Pattern A," the same as the "initial state." In other words, between the "return 45° rotation state" and the "return initial state," the lift-up and lift-down of the rotating shaft 15 and the flow path switching occur simultaneously.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 1 of this embodiment described above, the flow path of the fluid is configured to be switchable between two patterns, as in the third embodiment, and the rotating shaft 15 is of the "one-side idling type," so that it is possible to obtain the same functions and effects as the third embodiment. However, in this embodiment, the "switching angle" of the flow path is different from the "idling angle" of the rotating shaft 15, and therefore the operation of the rotating disk 14 and the rotating shaft 15 when switching the flow path is different from that of the third embodiment.

In this embodiment, as shown in Figures 47(A) to 47(C), when the rotating disk 14 rotates, the rotating shaft 15 lifts down (the gap between the fixed disk 13 and the upper housing 11 returns to its original state), and as shown in Figures 49(A) to 49(C), the rotating shaft 15 lifts up and down (the gap between the fixed disk 13 and the upper housing 11 temporarily widens and then returns to its original state). As a result, when the rotating disk 14 rotates, the surface pressure applied to the seal members 17, 18 between the fixed disk 13 and the rotating disk 14 is reduced, preventing the seal members 17, 18 from coming loose due to sliding wear or snagging.

Fifth Embodiment
Next, the fifth embodiment will be described in detail with reference to FIGS. 50(A) to 58(C).

[Switching flow path patterns]
The flow path switching device 1 of this embodiment differs from the second embodiment in that the flow path switching pattern of the fluid can be switched between three patterns. Figures 50(A) to 58(C) show operation diagrams related to flow path pattern switching. The flow path switching device 1 of this embodiment is the same "one-side idling type" as the second embodiment.

First, Figures 50(A) to 50(C) show the "initial state" of the flow path switching device 1 of this embodiment, with Figure 50(A) being an image showing the engagement relationship between the through-hole 14a of the rotating disk 14 and the rotating shaft 15. Each of Figures 51 to 58 (A), described later, is an image similar to Figure 50(A). Figure 50(B) is an image showing changes in the lift of the rotating shaft 15 relative to the rotating shaft angle. Each of Figures 51 to 58 (B), described later, is an image similar to Figure 50(B). Figure 50(C) is a plan view similar to Figure 21, showing the rotational positions of the rotating disk 14 and the rotation communicating passage 40. Each of Figures 51 to 58 (C), described later, is a plan view similar to Figure 50(C).

In this "initial state," as shown in Figure 50(A), the rotating shaft 15 engages with one inner wall of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 50(B). The rotating disk 14 and rotation communication passage 40 are positioned as shown in Figure 50(C). The disk rotation angle at this time is "0°," and the flow path switching state is the same as "Pattern A" in the third embodiment.

Next, we will explain the changes from the "initial state" in order. Figures 51(A) to 51(C) show the "45° rotated state" in which the rotating shaft 15 has rotated "45°" clockwise from the "initial state." In this state, as shown in Figure 51(A), the rotating shaft 15 rotates 45° clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and the shaft protrusion 15b rides up on the disk protrusion 13g, causing the rotating shaft 15 to lift up as shown in Figure 51(B). Furthermore, as shown in Figure 51(C), the disk rotation angle remains at "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as in the "initial state."

Next, Figures 52(A) to 52(C) show the "90° rotation state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "45° rotation state." In this state, as shown in Figure 52(A), the rotating shaft 15 rotates 45° clockwise together with the rotating disc 14, and the shaft protrusion 15b rides down into the disc recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 52(B). Also, as shown in Figure 52(C), the disc rotation angle is 45°, and the flow path switching state of the rotation communication passage 40 is the same as "Pattern B" in the second embodiment. In other words, between the "45° rotation state" and the "90° rotation state," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

As mentioned above, in this embodiment, the "switching angle" for switching the flow path and the "idling angle" of the rotating shaft 15 clockwise are the same, at 45°.

Next, Figures 53(A) to 53(C) show the "135° rotation state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "90° rotation state." In this state, as shown in Figure 53(A), the rotating shaft 15 rotates 45° clockwise together with the rotating disc 14, and the shaft protrusion 15b rides up onto the disc protrusion 13g, causing the rotating shaft 15 to lift up as shown in Figure 53(B). Also, as shown in Figure 53(C), the disc rotation angle is 90°, and the flow path switching state of the rotation communication passage 40 is the same as "Pattern C" in the second embodiment. In other words, between the "90° rotation state" and the "135° rotation state," the rotating shaft 15 is lifted up and the flow path is switched simultaneously.

Next, Figures 54(A) to 54(C) show the "90° return rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "135° rotation state." In this state, as shown in Figure 54(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 54(B). Also, as shown in Figure 54(C), the disk rotation angle remains at 90°, and the flow path switching state of the rotation communicating passage 40 is "Pattern C."

Next, Figures 55(A) to 55(C) show the "45° back rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "90° back rotation state." In this state, as shown in Figure 55(A), the rotating shaft 15 rotates 45° counterclockwise together with the rotating disk 14, and the shaft protrusion 15b rides up onto the disk protrusion 13g, causing the rotating shaft 15 to lift up as shown in Figure 55(B). Also, as shown in Figure 55(C), the disk rotation angle is 45°, and the flow path switching state of the rotation communication passage 40 is "Pattern B." In other words, between the "90° back rotation state" and the "45° back rotation state," the rotating shaft 15 is lifted up and the flow path is switched simultaneously.

Next, Figures 56(A) to 56(C) show the "re-rotated 90° state" in which the rotating shaft 15 has rotated 45° clockwise from the "returned 45° state." In this state, as shown in Figure 56(A), the rotating shaft 15 idles 45° clockwise and engages with the other inner wall of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 56(B). Also, as shown in Figure 56(C), the disk rotation angle remains at 45°, and the flow path switching state of the rotation communicating passage 40 remains in "pattern B."

Next, Figures 57(A) to 57(C) show the "return 45° rotation state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "re-rotated 90° state." In this state, as shown in Figure 57(A), the rotating shaft 15 rotates 45° counterclockwise and engages with one of the inner walls of the through-hole 14a, and the shaft protrusion 15b rides up onto the disk protrusion 13g, lifting the rotating shaft 15 up as shown in Figure 57(B). Also, as shown in Figure 57(C), the disk rotation angle remains at 45°, and the flow path switching state of the rotation communicating passage 40 remains in "pattern B."

Figures 58(A) to 58(C) show the "return initial state" in which the rotating shaft 15 has rotated 45 degrees counterclockwise from the "return 45° rotation state." In this state, as shown in Figure 58(A), the rotating shaft 15 rotates 45 degrees counterclockwise together with the rotating disk 14, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 58(B). Also, as shown in Figure 58(C), the disk rotation angle returns to 0°, and the flow path switching state of the rotation communication passage 40 is "pattern A," the same as the "initial state." In other words, between the "return 45° rotation state" and the "return initial state," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

[Operation and effect of the flow path switching device]
The configuration of the flow path switching device 1 of this embodiment described above differs from that of the second embodiment in that the flow path of the fluid can be switched between three patterns.

In this embodiment, as shown in Figures 52(A) to 52(C) and 58(A) to 58(C), when the rotating disk 14 rotates, the rotating shaft 15 lifts down (the fixed disk 13 and the upper housing 11 return to their original spacing). As a result, when the rotating disk 14 rotates, the surface pressure applied to each seal member 17, 18 between the fixed disk 13 and the upper housing 11 is reduced, which means that the seal members 17, 18 can be prevented from coming loose due to sliding wear or snagging.

In this embodiment, in a configuration where only one side is idling and the flow path can be switched between three patterns, the clockwise "idling angle" of the rotating shaft 15 and the flow path "switching angle" are set to the same "45°". Therefore, as shown in Figures 52(A) to 52(C) and 58(A) to 58(C), when switching the flow path, the rotating shaft 15 is lifted up, and then the flow path is switched and the rotating shaft 15 is lifted down simultaneously. This allows the drive torque of the rotating shaft 15 (drive torque of the drive unit 4) to be reduced, enabling the drive unit 4 (motor) to be made more compact.

Sixth Embodiment
Next, the sixth embodiment will be described in detail with reference to FIGS.

[Appearance of the flow path switching device]
Figure 59 is a perspective view of the top side of the flow path switching device 8 of this embodiment. Figure 60 is a perspective view of the bottom side of the flow path switching device 8. Figure 61 is a plan view of the flow path switching device 8. Figure 62 is a plan view of the flow path switching device 8 with the upper housing 11 and drive unit 4 removed. This embodiment differs from the previous embodiments in the arrangement of the inflow flow paths 20 in the upper housing 11, the arrangement of the outflow flow paths 30 in the lower housing 12, the shape and arrangement of the rotary communicating passages 40 in the rotary disk 14, and the arrangement of the fixed communicating passages 50 in the fixed disk 13.

That is, as shown in Figures 59 and 61, in this embodiment, the four inflow passages 20 (21-24) are arranged biasedly on approximately one half of the top surface of the upper housing 11, with adjacent inflow passages 20 (21-24) spaced at equal angular intervals (60°). Also, as shown in Figure 60, in this embodiment, the four outflow passages 30 (31-34) are arranged biasedly on approximately one half of the top surface of the lower housing 12, corresponding to the four inflow passages 20 (21-24), with adjacent adjacent passages spaced at equal angular intervals (60°).

As shown in Figure 62, the rotation communication passages 40 provided in the rotary disk 14 have the same short curved shape for the first rotation communication passage 41 to the third rotation communication passage 43, with only the fourth rotation communication passage 44 having a long curved shape. The upper seal members 17 provided around each rotation communication passage 40 have a shape that matches the shape of the corresponding rotation communication passage 40 (41 to 44). The lower seal member 18 is similar to the upper seal member 17.

In this embodiment, the flow path switching device 8 further includes a control unit 5 that controls the drive unit 4 to switch the fluid flow path, as shown in FIG. 59. This control unit 5 stores a predetermined control program and controls the drive unit 4 to execute the "flow path switching control" described below.

[Sliding resistance reduction structure]
The flow path switching device 8 of this embodiment also differs from the previous embodiments in the configuration of the "sliding resistance reducing structure." Figure 63 shows an enlarged plan view of the through hole 14a and the rotating shaft 15 of Figure 62. Figure 64 shows a perspective view of the rotating shaft 15 of this embodiment. Figure 65 shows an enlarged perspective view of the engaging structure K1 at the tip of the rotating shaft 15 shown in Figure 64. Figure 66 shows a plan view of the fixed disk 13 of this embodiment. Figure 67 shows an enlarged perspective view of the engaged structure K2 of the fixed disk 13 shown in Figure 66.

In this embodiment, the basic configuration of the fixed disk 13, rotating disk 14, rotating shaft 15, upper seal member 17, and lower seal member 18 is similar to that of the previous embodiments, except for the arrangement and shape of the inlet flow path 20, outlet flow path 30, and rotary communication path 40. However, the configuration differs in the following respects. That is, as shown in Figure 66, the fixed communication paths 50 (51-54) of the fixed disk 13 are arranged biased toward approximately one half of the upper surface of the fixed disk 13 to match the arrangement of the outlet flow path 30 of the lower housing 12, and adjacent paths are spaced at equal angular intervals (60°).

This embodiment also differs from the previous embodiments in the configuration of the engagement structure K1 at the tip of the rotating shaft 15 and the engaged structure K2 of the fixed disk 13. That is, as shown in Figures 64 and 65, the engagement structure K1 provided at the tip of the rotating shaft 15, unlike the previous embodiments, includes two shaft protrusions 15b and two shaft recesses 15c aligned in the circumferential direction. The two shaft protrusions 15b are spaced apart at equal angles (180°), with a shaft recess 15c between them. Each shaft protrusion 15b has the same shape as in the previous embodiments, and the circumferential length of the bottom of each shaft recess 15c is greater than that in the previous embodiments.

On the other hand, as shown in Figures 66 and 67, the disk protrusions 13g and disk recesses 13e that make up the engaged structure K2 of the fixed disk 13 are arranged at equal angular intervals (90°). Each disk protrusion 13g includes a side surface 13i that slopes in the circumferential direction (arrangement direction). The slope angles of both side surfaces 13i are set to the same. These side surfaces 13i also form the side surfaces of the disk recesses 13e. In this embodiment, the top surface 13h of each disk protrusion 13g is flat, and both sides of the top surface 13h form sloped side surfaces 13i. Furthermore, the bottom of each disk recess 13e is flat.

[Switching flow path patterns]
The flow path switching device 8 of this embodiment has the above-described configuration, and is therefore capable of switching the flow path of the fluid between three patterns. Figures 68(A) to 80(D) show operational diagrams related to the switching of the flow path patterns.

First, Figures 68(A) to 68(D) show the "initial state" of the flow path switching device 8 of this embodiment, with Figure 68(A) being an image showing the engagement relationship between the through-hole 14a of the rotating disk 14 and the rotating shaft 15. (A) in Figures 69 to 80, which will be described later, is an image similar to Figure 68(A). Figure 68(B) is an image showing the change in lift of the rotating shaft 15 relative to the rotating shaft angle. (B) in Figures 69 to 80, which will be described later, is an image similar to Figure 68(B). Figure 68(C) is a plan view showing the rotational position of the through-hole 14a and the rotating shaft 15, and the positional relationship between the disk convex portion 13g, the disk concave portion 13e, and the shaft convex portion 15b. (C) in Figures 69 to 80, which will be described later, is a plan view similar to Figure 68(C). Figure 68(D) is a plan view similar to Figure 62, showing the rotational positions of the rotary disc 14 and the rotation communication passage 40. Each of Figures 69 to 80 (D), described below, is a plan view similar to Figure 68(D).

In this "initial state," as shown in Figure 68(A), the rotating shaft 15 is positioned in a state in which there are gaps 28 on both sides of the through-hole 14a in the direction of rotation. As shown in Figure 68(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 68(C), the shaft protrusion 15b rests on the disk recess 13e. Furthermore, the rotating disk 14 and rotation communication passage 40 are positioned as shown in Figure 68(D). At this time, the first rotation communication passage 41 communicates with the first inflow passage 21 and the first fixed communication passage 51, the second rotation communication passage 42 communicates with the second inflow passage 22 and the second fixed communication passage 52, the third rotation communication passage 43 communicates with the third inflow passage 23 and the third fixed communication passage 53, and the fourth rotation communication passage 44 communicates with the fourth inflow passage 24 and the fourth fixed communication passage 54. The disk rotation angle at this time is defined as "0°," and this flow path switching state is defined as "Pattern A."

Next, we will explain the changes from the "initial state." Figures 69(A) to 69(D) show the "30° rotation state" in which the rotating shaft 15 has rotated "30°" clockwise from the "initial state." In this state, as shown in Figure 69(A), the rotating shaft 15 has rotated "30°" clockwise from the "initial state" and is engaged with one inner wall of the through-hole 14a, and as shown in Figure 69(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 69(C), the shaft protrusion 15b rides on one side edge of the apex 13h of the disk protrusion 13g. Furthermore, as shown in Figure 69(D), the disk rotation angle remains "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as in the "initial state."

As described above, in this embodiment, the "idling angle" at which the rotating shaft 15 rotates clockwise when the shaft protrusion 15b moves from the disk recess 13e onto the disk protrusion 13g is set to "30°." Also, in this embodiment, in the "initial state" shown in Figure 68(A), the rotating shaft 15 is positioned in the through-hole 14a with gaps 28 on both sides of the rotational direction, making the rotating shaft 15 a "double-sided idling type" that can rotate clockwise and counterclockwise.

Next, Figures 70(A) to 70(D) show the "60° rotation state" in which the rotating shaft 15 has rotated a further 30° clockwise from the "30° rotation state." In this state, as shown in Figure 70(A), the rotating shaft 15 rotates 30° clockwise together with the rotating disk 14, and as shown in Figure 70(B), the rotating shaft 15 rotates clockwise while remaining lifted up. Also, as shown in Figure 70(C), the shaft protrusion 15b rides on the other side edge of the top 13h of the disk protrusion 13g. Furthermore, as shown in Figure 70(D), the rotation communicating passage 40 has rotated 30° clockwise. In this "60° rotation state," the first rotation communication passage 41 communicates with the second inflow passage 22 and the first fixed communication passage 51, the second rotation communication passage 42 communicates with the third inflow passage 23 and the second fixed communication passage 52, the third rotation communication passage 43 communicates with the fourth inflow passage 24 and the third fixed communication passage 53, and the fourth rotation communication passage 44 communicates with the first inflow passage 21 and the fourth fixed communication passage 54. The disc rotation angle at this time is "30°," and this flow passage switching state is defined as "Pattern B." In other words, between the "30° rotation state" and the "60° rotation state," the rotation shaft 15 is lifted up and the flow passages are switched simultaneously.

As described above, in this embodiment, the "switching angle" at which the rotary disk 14 is rotated to switch the flow paths of the flow path switching device 8 is set to "30°." In other words, in this embodiment, the "idling angle" of the rotating shaft 15 clockwise and the "switching angle" of the rotary disk 14 for switching the flow paths are set to the same value of "30°."

Next, Figures 71(A) to 71(D) show the "30° return rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "60° rotation state." In this state, as shown in Figure 71(A), the rotating shaft 15 idles 30° counterclockwise, and as shown in Figure 71(B), the rotating shaft 15 rotates counterclockwise while remaining lifted. Also, as shown in Figure 71(C), the shaft protrusion 15b rides on one side edge of the top 13h of the disk protrusion 13g. Furthermore, as shown in Figure 71(D), the rotation communicating passage 40 remains in the same position as in the "60° rotation state," and the disk rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as in the "60° rotation state."

Next, Figures 72(A) to 72(D) show the "0° return rotation state" in which the rotating shaft 15 has rotated a further 30° counterclockwise from the "30° return rotation state." In this state, as shown in Figure 72(A), the rotating shaft 15 rotates idly counterclockwise by 30° and engages with one of the inner walls of the through-hole 14a, and as shown in Figure 72(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 72(C), the shaft protrusion 15b rests on the disc recess 13e. Furthermore, as shown in Figure 72(D), the rotation communicating passage 40 remains in the same position as in the "30° return rotation state," and the disc rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as the "60° rotation state."

Next, Figures 73(A) to 73(D) show the "30° re-rotation state" in which the rotating shaft 15 has rotated 30° clockwise from the "0° return rotation state." In this state, as shown in Figure 73(A), the rotating shaft 15 idles 30° clockwise from the "0° return rotation state," and as shown in Figure 73(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 73(C), the shaft protrusion 15b rides on one side edge of the apex 13h of the disk protrusion 13g. Furthermore, as shown in Figure 73(D), the rotation communicating passage 40 remains in the same position as in the "0° return rotation state," and the disk rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as the "0° return rotation state."

Next, Figures 74(A) to 74(D) show the "60° re-rotation state" in which the rotating shaft 15 has rotated 30° clockwise from the "30° re-rotation state." In this state, as shown in Figure 74(A), the rotating shaft 15 rotates 30° clockwise and engages with the other inner wall of the through-hole 14a. As shown in Figure 74(B), the rotating shaft 15 rotates clockwise while remaining lifted up. Also, as shown in Figure 74(C), the shaft protrusion 15b rides on the other side edge of the top 13h of the disk protrusion 13g. Furthermore, as shown in Figure 74(D), the rotation communicating passage 40 remains in the same position as in the "30° re-rotation state," and the disk rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as in the "30° re-rotation state."

Next, Figures 75(A) to 75(D) show the "90° rotation state" in which the rotating shaft 15 has rotated "30°" clockwise from the "60° re-rotation state." In this state, as shown in Figure 75(A), the rotating shaft 15 rotates "30°" clockwise together with the rotating disk 14, and as shown in Figure 75(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 75(C), the shaft protrusion 15b rides down from the top 13h of the disk protrusion 13g onto the disk recess 13e. Furthermore, as shown in Figure 74(D), the rotation communicating passage 40 has rotated "30°" clockwise. In this "90° rotation state," the first rotation communication passage 41 communicates with the second inflow passage 22 and the second fixed communication passage 52, the second rotation communication passage 42 communicates with the third inflow passage 23 and the third fixed communication passage 53, the third rotation communication passage 43 communicates with the fourth inflow passage 24 and the fourth fixed communication passage 54, and the fourth rotation communication passage 44 communicates with the first inflow passage 21 and the first fixed communication passage 51. The disc rotation angle at this time is "60°," and the passage switching state at this time is defined as "Pattern C." In other words, between the "re-60° rotation state" and the "90° rotation state," the rotation shaft 15 is lifted down and the passages are switched simultaneously.

Next, Figures 76(A) to 76(D) show the "60° return rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "90° rotation state." In this state, as shown in Figure 76(A), the rotating shaft 15 rotates 30° counterclockwise, and as shown in Figure 76(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 76(C), the shaft protrusion 15b rides on the other side edge of the top 13h of the disk protrusion 13g. Furthermore, as shown in Figure 76(D), the rotation communicating passage 40 remains in the same position as in the "90° rotation state," and the disk rotation angle remains at 60°. The flow path switching state at this time is "Pattern C," the same as in the "90° rotation state."

Next, Figures 77(A) to 77(D) show the "30° Return Rotation State" in which the rotating shaft 15 has rotated 30° counterclockwise from the "60° Return Rotation State." In this state, as shown in Figure 77(A), the rotating shaft 15 rotates 30° counterclockwise and engages with one inner wall of the through-hole 14a. As shown in Figure 77(B), the rotating shaft 15 rotates counterclockwise while remaining lifted up. Also, as shown in Figure 77(C), the shaft protrusion 15b rides on one side edge of the apex 13h of the disk protrusion 13g. Furthermore, as shown in Figure 77(D), the rotation communicating passage 40 remains in the same position as in the "60° Return Rotation State," and the disk rotation angle remains at 60°. The flow path switching state at this time is "Pattern C," the same as the "60° Return Rotation State."

Next, Figures 78(A) to 78(D) show the "0° return rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "30° return rotation state." In this state, as shown in Figure 78(A), the rotating shaft 15 rotates 30° counterclockwise together with the rotating disk 14, and as shown in Figure 78(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 78(C), the shaft protrusion 15b rests on the disk recess 13e. Furthermore, as shown in Figure 78(D), the rotation communication passage 40 has rotated 30° counterclockwise. The disk rotation angle at this time is 30°, and the flow path switching state is "Pattern B." In other words, between the "30° return rotation state" and the "0° return rotation state," the rotating shaft 15 is lifted down and the flow path is switched simultaneously.

Next, Figures 79(A) to 79(D) show the "-30° rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "return 0° rotation state." In this state, as shown in Figure 79(A), the rotating shaft 15 rotates 30° counterclockwise together with the rotating disk 14, and as shown in Figure 79(B), the rotating shaft 15 is lifted up. Also, as shown in Figure 79(C), the shaft protrusion 15b rides on the disk protrusion 13g. Furthermore, as shown in Figure 79(D), the rotation communication passage 40 has rotated 30° counterclockwise. The disk rotation angle at this time is 0°, and the flow path switching state is "pattern A." In other words, between the "return 0° rotation state" and the "-30° rotation state," the lifting up of the rotating shaft 15 and the flow path switching occur simultaneously.

Figures 80(A) to 80(D) show the "return initial state" in which the rotating shaft 15 has rotated "30°" clockwise from the "-30° rotation state." In this state, as shown in Figure 80(A), the rotating shaft 15 rotates idly "30°" clockwise, and as shown in Figure 80(B), the rotating shaft 15 is lifted down. Also, as shown in Figure 80(C), the shaft protrusion 15b rests on the disc recess 13e. Furthermore, as shown in Figure 80(D), the rotation communicating passage 40 remains in the same position as in the "initial state," and the disc rotation angle is "0°." The flow path switching state at this time is "Pattern A," the same as the "initial state."

[Regarding flow path switching control]
Next, a description will be given of the "flow path switching control" executed by the control unit 5 in the flow path switching device 8 of this embodiment. Figures 81 to 83 show an example of the control content in the form of a flowchart.

When processing transitions to this control routine, the control unit 5 acquires the rotation angle (rotation shaft angle) Sdeg of the rotation shaft 15 in step 100. Here, a first angle sensor (not shown) that detects the rotation shaft angle Sdeg is provided in the housing 2 of the flow path switching device 8, and the control unit 5 acquires the rotation shaft angle Sdeg based on the detection value of that angle sensor.

Next, in step 110, the control unit 5 determines whether there is a request to switch the flow path. This switch request can be assumed to be issued, for example, by a control device that controls the fluid circuit in which the flow path switching device 8 is installed. If the result of this determination is positive, the control unit 5 proceeds to step 120, and if the result of this determination is negative, the control unit 5 proceeds to step 220.

In step 220, the control unit 5 maintains the switching position of the flow path switching device 8 and returns the process to step 100.

In step 120, the control unit 5 acquires the stop angle (pre-switching disk stop angle) TSTA of the rotating disk 14 before switching. Here, a second angle sensor (not shown) that detects the disk rotation angle is provided in the housing 2 of the flow path switching device 8, and the control unit 5 acquires the pre-switching disk stop angle TSTA based on the detection value of that angle sensor.

In step 130, the control unit 5 acquires the stop angle (switching request disk stop angle) TSTO of the rotating disk 14 for which switching is requested. This switching request disk stop angle TSTO can be assumed to be transmitted, for example, by a control device that controls the fluid circuit in which the flow path switching device 8 is installed.

Next, in step 140, the control unit 5 determines whether the pre-switching disc stop angle TSTA is "0 deg," i.e., "0°." If the result of this determination is positive, the control unit 5 proceeds to step 150; if the result of this determination is negative, the control unit 5 proceeds to step 320.

In step 150, the control unit 5 determines whether the switching request disc stop angle TSTO is "30 deg," i.e., "30°." If the result of this determination is positive, the control unit 5 proceeds to step 160; if the result of this determination is negative, the control unit 5 proceeds to step 280.

In step 160, the control unit 5 determines whether the reversal control flag XRC is "0." As described below, the control unit 5 sets this flag XRC to "1" when the rotating shaft 15 is rotated counterclockwise, and to "0" when the rotating shaft 15 is rotated clockwise. If the result of this determination is positive, the control unit 5 proceeds to step 170; if the result of this determination is negative, the control unit 5 proceeds to step 230.

In step 170, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate clockwise.

Next, in step 180, the control unit 5 determines whether the rotation axis angle Sdeg is equal to or greater than 60deg, i.e., 60°. If the result of this determination is positive, the control unit 5 proceeds to step 190; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 190, the control unit 5 controls the drive unit 4 to stop the clockwise drive of the rotation shaft 15.

Next, in step 200, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate counterclockwise.

Next, in step 210, the control unit 5 sets the reversal control flag XRC to "1."

On the other hand, moving from step 160 to step 230, the control unit 5 determines whether the rotation axis angle Sdeg is "0deg," i.e., "0°" or less. If the result of this determination is positive, the control unit 5 proceeds to step 240; if the result of this determination is negative, the control unit 5 returns to step 100.

Next, in step 240, the control unit 5 controls the drive unit 4 to stop the counterclockwise drive of the rotation shaft 15.

Next, in step 250, the control unit 5 sets the pre-switching disc stop angle TSTA to "30 deg", i.e., "30°".

Next, in step 260, the control unit 5 sets the reversal control flag XRC to "0."

Next, in step 270, the control unit 5 completes the flow path switching. That is, it cancels the switching request and returns processing to step 100.

On the other hand, moving from step 150 to step 280, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate clockwise.

Next, in step 290, the control unit 5 determines whether the rotation axis angle Sdeg is "90deg," i.e., "90°" or greater. If the result of this determination is positive, the control unit 5 proceeds to step 300; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 300, the control unit 5 controls the drive unit 4 to stop the clockwise drive of the rotation shaft 15.

Next, in step 310, the control unit 5 sets the pre-switching disc stop angle TSTA to "60 deg", i.e., "60°", and proceeds to step 260.

On the other hand, moving from step 140 to step 320, the control unit 5 determines whether the pre-switching disc stop angle TSTA is "30 degrees." If the result of this determination is positive, the control unit 5 proceeds to step 330, and if the result of this determination is negative, the control unit 5 proceeds to step 470.

Then, moving from step 320 to step 330, the control unit 5 determines whether the switching request disc stop angle TSTO is "0 deg," i.e., "0°." If the result of this determination is positive, the control unit 5 proceeds to step 340; if the result of this determination is negative, the control unit 5 proceeds to step 400.

In step 340, the control unit 5 determines whether the reversal control flag XRC is "0." If the result of this determination is positive, the control unit 5 proceeds to step 350; if the result of this determination is negative, the control unit 5 proceeds to step 440.

In step 350, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate counterclockwise.

Next, in step 360, the control unit 5 determines whether the rotation axis angle Sdeg is "-30deg," i.e., "-30°" or less. If the result of this determination is positive, the control unit 5 proceeds to step 370; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 370, the control unit 5 controls the drive unit 4 to stop the counterclockwise drive of the rotation shaft 15.

Next, in step 380, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate clockwise.

Next, in step 390, the control unit 5 sets the reversal control flag XRC to "1" and returns the process to step 100.

On the other hand, moving from step 330 to step 400, the control unit 5 controls the drive unit 4 to rotate the rotation shaft 15 clockwise.

Next, in step 410, the control unit 5 determines whether the rotation axis angle Sdeg is equal to or greater than 90deg. If the result of this determination is positive, the control unit 5 proceeds to step 420; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 420, the control unit 5 controls the drive unit 4 to stop the clockwise drive of the rotation shaft 15.

Next, in step 430, the control unit 5 sets the pre-switching disc stop angle TSTA to "60 degrees" and proceeds to step 260.

On the other hand, moving from step 340 to step 440, the control unit 5 determines whether the rotation axis angle Sdeg is equal to or greater than 0deg. If the result of this determination is positive, the control unit 5 proceeds to step 450, and if the result of this determination is negative, the control unit 5 returns to step 100.

In step 450, the control unit 5 controls the drive unit 4 to stop the clockwise drive of the rotation shaft 15.

Next, in step 460, the control unit 5 sets the pre-switching disc stop angle TSTA to "0 degrees" and proceeds to step 260.

On the other hand, moving from step 320 to step 470, the control unit 5 determines whether the switching request disc stop angle TSTO is "0 degrees." If the result of this determination is positive, the control unit 5 proceeds to step 480, and if the result of this determination is negative, the control unit 5 proceeds to step 540.

In step 480, the control unit 5 determines whether the reversal control flag XRC is "0". If the result of this determination is positive, the control unit 5 proceeds to step 490; if the result of this determination is negative, the control unit 5 proceeds to step 580.

In step 490, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate counterclockwise.

Next, in step 500, the control unit 5 determines whether the rotation axis angle Sdeg is less than or equal to -30deg. If the result of this determination is positive, the control unit 5 proceeds to step 510; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 510, the control unit 5 controls the drive unit 4 to stop the counterclockwise drive of the rotation shaft 15.

Next, in step 520, the control unit 5 controls the drive unit 4 to drive the rotation shaft 15 to rotate clockwise.

Next, in step 530, the control unit 5 sets the reversal control flag XRC to "1" and returns the process to step 100.

On the other hand, moving from step 470 to step 540, the control unit 5 controls the drive unit 4 to rotate the rotation shaft 15 counterclockwise.

Next, in step 550, the control unit 5 determines whether the rotation axis angle Sdeg is equal to or less than 0deg. If the result of this determination is positive, the control unit 5 proceeds to step 560; if the result of this determination is negative, the control unit 5 returns to step 100.

In step 560, the control unit 5 controls the drive unit 4 to stop the counterclockwise drive of the rotation shaft 15.

Next, in step 570, the control unit 5 sets the pre-switching disc stop angle TSTA to "30 degrees" and proceeds to step 260.

On the other hand, moving from step 480 to step 580, the control unit 5 determines whether the rotation axis angle Sdeg is equal to or greater than 0deg. If the result of this determination is positive, the control unit 5 proceeds to step 590, and if the result of this determination is negative, the control unit 5 returns to step 100.

In step 590, the control unit 5 controls the drive unit 4 to stop the clockwise drive of the rotation shaft 15.

Next, in step 600, the control unit 5 sets the pre-switching disc stop angle TSTA to "0 degrees" and proceeds to step 260.

In this embodiment, the drive unit 4 corresponds to an example of the "drive means" of the disclosed technology, and the control unit 5 corresponds to an example of the "control means" of the disclosed technology. The control unit 5 controls the drive unit 4 to rotate the rotating shaft 15 clockwise, switching the flow path when the tip of the rotating shaft 15 abuts the fixed disk 13, i.e., when the apex 15e of the shaft protrusion 15b abuts the apex 13h of the disk protrusion 13g, and then rotates the rotating shaft 15 counterclockwise (in the reverse direction), stopping the rotation of the rotating shaft 15 when the tip of the rotating shaft 15 engages with the fixed disk 13, i.e., when the shaft recess 15c and shaft protrusion 15b engage with the disk protrusion 13g and disk recess 13e.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 8 of this embodiment described above, the control unit 5 controls the drive unit 4 to rotate the rotating shaft 15, switching the flow path when the top 15e of the shaft protrusion 15b abuts against the top 13h of the disk protrusion 13g (widening the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14), and then rotate the rotating shaft 15 counterclockwise (in the reverse direction) to stop the rotation of the rotating shaft 15 when the shaft protrusion 15b and the shaft recess 15c engage with the disk recess 13e and the disk protrusion 13g (returning the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 to their original states). This ensures that the gap between the upper housing 11 and the rotating disk 14 and the gap between the fixed disk 13 and the rotating disk 14 are reliably returned to their original states after switching the flow path. This ensures the sealing performance of the upper seal member 17 and the lower seal member 18.

In this embodiment, as shown in Figures 75(A) to 75(D) and 78(A) to 78(D), when the rotating disk 14 rotates, the rotating shaft 15 lifts down (returning the fixed disk 13 and upper housing 11 to their original spacing). This reduces the surface pressure on the seal members 17, 18 between the fixed disk 13 and upper housing 11 when the flow path switches, preventing the seal members 17, 18 from coming loose due to sliding wear or snagging. Additionally, unlike the previous embodiments, in this embodiment, as shown in Figures 70(A) to 70(D), the rotating disk 14 rotates while the rotating shaft 15 remains lifted up (keeping the gap between the fixed disk 13 and upper housing 11 wide). This more reliably prevents the seal members 17, 18 from coming loose due to sliding wear or snagging when the flow path switches.

In this embodiment, in a "double-sided idling type" configuration where the flow path can be switched between three patterns, the "idling angle" of the rotating shaft 15 and the "switching angle" of the flow path are set to the same value of 30°. Therefore, as shown in Figures 70(A) to 70(D), 75(A) to 75(D), and 78(A) to 78(D), when switching the flow path, the rotating shaft 15 is lifted up, and then the flow path is switched and the rotating shaft 15 is either lifted up or lifted down simultaneously. This allows for a reduction in the drive torque of the rotating shaft 15 (drive torque of the drive unit 4), enabling the drive unit 4 (motor) to be made more compact.

Seventh Embodiment
Next, the seventh embodiment will be described in detail with reference to FIGS. 84(A) to 90(C).

[Switching flow path patterns]
The flow path switching device 8 of this embodiment differs from that of the sixth embodiment in the switching pattern of the fluid flow path. That is, in this embodiment, the fluid flow path can be switched between two patterns in the same "double-side idle type" as in the sixth embodiment. Figures 84(A) to 90(C) show operational diagrams related to the switching of the flow path pattern.

First, Figures 84(A) to 84(C) show the "initial state" of the flow path switching device 8 of this embodiment, with Figure 84(A) being an image showing the engagement relationship between the through-hole 14a of the rotary disk 14 and the rotary shaft 15. Each of Figures 85 to 90 (A), which will be described later, is an image similar to Figure 84(A). Figure 84(B) is an image showing the change in lift of the rotary shaft 15 relative to the rotary shaft angle. Each of Figures 85 to 90 (B), which will be described later, is an image similar to Figure 84(B). Figure 84(C) is a plan view similar to Figure 62, showing the rotational positions of the rotary disk 14 and the rotary communication passage 40. Each of Figures 85 to 90 (C), which will be described later, is a plan view similar to Figure 84(C).

In this "initial state," as shown in FIG. 84(A), the rotating shaft 15 is positioned in the through-hole 14a with gaps 28 on both sides in the rotational direction. The shaft protrusion 15b rides down on the disk recess 13e, causing the rotating shaft 15 to lift down as shown in FIG. 84(B). The rotating disk 14 and rotation communication passage 40 are positioned as shown in FIG. 84(C). At this time, the first rotation communication passage 41 communicates with the first inflow passage 21 and the first fixed communication passage 51, the second rotation communication passage 42 communicates with the second inflow passage 22 and the second fixed communication passage 52, the third rotation communication passage 43 communicates with the third inflow passage 23 and the third fixed communication passage 53, and the fourth rotation communication passage 44 communicates with the fourth inflow passage 24 and the fourth fixed communication passage 54. The disk rotation angle at this time is defined as "0°," and this flow path switching state is defined as "Pattern A."

Next, we will explain the changes from the "initial state" one by one. Figures 85(A) to 85(C) show the "30° rotation state" in which the rotating shaft 15 has rotated "30°" clockwise from the "initial state." In this state, as shown in Figure 85(A), the rotating shaft 15 rotates 30° clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and the shaft protrusion 15b rides up onto one side edge of the apex 13h of the disk protrusion 13g, causing the rotating shaft 15 to lift up as shown in Figure 85(B). Furthermore, as shown in Figure 85(C), the disk rotation angle remains "0°," and the flow path switching state of the rotation communicating passage 40 is "Pattern A," the same as in the "initial state."

Next, Figures 86(A) to 86(C) show the "60° rotation state" in which the rotating shaft 15 has rotated "30°" clockwise from the "30° rotation state." In this state, as shown in Figure 85(A), the rotating shaft 15 rotates "30°" clockwise together with the rotating disk 14, and the shaft protrusion 15b rides on the other side edge of the top 13h of the disk protrusion 13g, causing the rotating shaft 15 to rotate clockwise while remaining lifted up, as shown in Figure 86(B). Also, as shown in Figure 86(C), the rotation communicating passage 40 rotates "30°" clockwise. In this "30° rotation state," the first rotation communication passage 41 communicates with the second inflow passage 22 and the first fixed communication passage 51, the second rotation communication passage 42 communicates with the third inflow passage 23 and the second fixed communication passage 52, the third rotation communication passage 43 communicates with the fourth inflow passage 24 and the third fixed communication passage 53, and the fourth rotation communication passage 44 communicates with the first inflow passage 21 and the fourth fixed communication passage 54. The disc rotation angle at this time is "30°," and this flow passage switching state is defined as "Pattern B."

As described above, in this embodiment, the "switching angle" at which the rotary disk 14 is rotated to switch the flow paths of the flow path switching device 8 is set to "30°." In other words, in this embodiment, the "idling angle" of the rotating shaft 15 clockwise and the "switching angle" of the rotary disk 14 for switching the flow paths are set to the same value of "30°."

Next, Figures 87(A) to 87(C) show the "30° return rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "60° rotation state." In this state, as shown in Figure 87(A), the rotating shaft 15 idles 30° counterclockwise, and the shaft protrusion 15b rides onto one side edge of the apex 13h of the disk protrusion 13g, causing the rotating shaft 15 to rotate counterclockwise while remaining lifted up, as shown in Figure 87(B). Also, as shown in Figure 87(C), the rotation communicating passage 40 remains in the same position as in the "60° rotation state," and the disk rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as in the "60° rotation state."

Next, Figures 88(A) to 88(C) show the "0° Return Rotation State" in which the rotating shaft 15 has rotated a further 30° counterclockwise from the "30° Return Rotation State." In this state, as shown in Figure 88(A), the rotating shaft 15 rotates idly counterclockwise by 30° and engages with one inner wall of the through-hole 14a, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 88(B). Also, as shown in Figure 88(C), the rotation communicating passage 40 remains in the same position as in the "30° Return Rotation State," and the disk rotation angle remains at 30°. The flow path switching state at this time is "Pattern B," the same as in the "30° Return Rotation State."

Next, Figures 89(A) to 89(C) show the "-30° rotation state" in which the rotating shaft 15 has rotated 30° counterclockwise from the "return 0° rotation state." In this state, as shown in Figure 89(A), the rotating shaft 15 rotates 30° counterclockwise together with the rotating disk 14, and the shaft protrusion 15b rides up on the disk protrusion 13g, causing the rotating shaft 15 to lift up as shown in Figure 89(B). Also, as shown in Figure 89(C), the rotating disk 14 and the rotation communication passage 40 have rotated 30° counterclockwise. The flow path switching state at this time is "Pattern A," the same as the "initial state."

Figures 90(A) to 90(C) show the "return initial state" in which the rotating shaft 15 has rotated "30°" clockwise from the "-30° rotation state." In this state, as shown in Figure 90(A), the rotating shaft 15 idles "30°" clockwise, and the shaft protrusion 15b rides down into the disk recess 13e, causing the rotating shaft 15 to lift down as shown in Figure 90(B). Also, as shown in Figure 90(C), the rotation communicating passage 40 has returned to the same position as in the "initial state," and the disk rotation angle is "0°." The flow path switching state at this time is "Pattern A."

[Operation and effect of the flow path switching device]
The configuration of the flow path switching device 8 of this embodiment described above is a "double-sided idling type" in which the rotating shaft 15 can idly rotate in both directions in the rotational direction from the "initial state," and the flow path can be switched between two patterns. Although a mode in which the flow path is switched simultaneously with the lift-down of the rotating shaft 15 and a mode in which the flow path is switched while the rotating shaft 15 is lifted up are mixed, a mode in which the flow path is switched while the rotating shaft 15 is lifted up can be added. That is, as shown in Figures 86(A) to 86(C), the rotating disk 14 rotates while the rotating shaft 15 is lifted up (while widening the gap between the fixed disk 13 and the upper housing 11). Therefore, it can be seen that the sliding wear and disconnection of the seal members 17 and 18 due to snagging can be suppressed when switching the flow paths.

Eighth Embodiment
Next, the eighth embodiment will be described in detail with reference to FIGS. 91(A) to 95(C).

[Regarding engaging and engaged structures]
This embodiment is a modification of the third embodiment, and differs from the third embodiment in the configurations of the engaging structure K1 and the engaged structure K2. In this embodiment, similar to the third embodiment, the fluid flow path is configured to be switchable between two patterns, and the rotating shaft 15 in the "initial state" is a "one-side free-spin type" that can only spin clockwise.

Figures 91(A) to 91(C) show the "initial state" of the flow path switching device 1 of this embodiment, and Figure 91(A) is the same conceptual diagram as Figure 40(A). Each of Figures 92 to 95 (A), which will be described later, is a conceptual diagram similar to Figure 91(A). Figure 91(B) is a conceptual diagram showing the relationship between the engaging structure K1 (shaft convex portion 15b and shaft concave portion 15c) and the engaged structure K2 (disk concave portion 13e and disk convex portion 13g) of this embodiment. Each of Figures 92 to 95 (B), which will be described later, is a conceptual diagram similar to Figure 91(B). As shown in Figures 91(B) to 95(B), in this embodiment, the apex 15e of the shaft convex portion 15b and the apex 13h of the disk convex portion 13g each form a convex curved surface. In this embodiment, the angle of inclination of the side surface 15d of the shaft protrusion 15b is set to be the same as the angle of inclination of the side surface 13i of the disk protrusion 13g and the disk recess 13e. Figure 91(C) is the same conceptual diagram as Figure 40(B). Each of Figures 92 to 95 (C), described below, is a conceptual diagram similar to Figure 91(C).

In the "initial state" shown in Figures 91(A) to 91(C), as shown in Figure 91(A), the rotating shaft 15 is positioned in the through-hole 14a with a gap 28 only in the clockwise direction, and as shown in Figures 91(B) and 91(C), the shaft protrusion 15b rests on the disc recess 13e, and the rotating shaft 15 is lifted down. In this state, as shown in Figure 91(B), the shaft protrusion 15b fits into and engages with the disc recess 13e.

Next, we will explain the changes from the "initial state" one by one. Figures 92(A) to 92(C) show the "45° rotated state" in which the rotating shaft 15 has rotated "45°" clockwise from the "initial state." In this state, as shown in Figure 92(A), the rotating shaft 15 rotates 45° clockwise from the "initial state" and engages with the other inner wall of the through-hole 14a, and as shown in Figures 92(B) and 92(C), the shaft protrusion 15b rides up on the disk protrusion 13g, lifting the rotating shaft 15. In this state, as shown in Figure 92(B), the top 15e of the shaft protrusion 15b rides up and abuts against the top 13h of the disk protrusion 13g.

Next, Figures 93(A) to 93(C) show the "90° rotated state" in which the rotating shaft 15 has rotated a further 45° clockwise from the "45° rotated state." In this state, as shown in Figure 93(A), the rotating shaft 15 has rotated 45° clockwise together with the rotating disc 14 from the "45° rotated state," and as shown in Figures 93(B) and 93(C), the shaft protrusion 15b rides down into the disc recess 13e, lifting the rotating shaft 15 down. In this state, as shown in Figure 93(B), the shaft protrusion 15b fits into and engages with the disc recess 13e.

Next, Figures 94(A) to 94(C) show the "return 45° rotated state" in which the rotating shaft 15 has rotated 45° counterclockwise from the "90° rotated state." In this state, as shown in Figure 94(A), the rotating shaft 15 rotates 45° counterclockwise from the "90° rotated state" and engages with one of the inner walls of the through-hole 14a, and as shown in Figures 94(B) and 94(C), the shaft protrusion 15b rides up on the disk protrusion 13g, lifting the rotating shaft 15 up. In this state, as shown in Figure 94(B), the top 15e of the shaft protrusion 15b rides up and abuts against the top 13h of the disk protrusion 13g.

Next, Figures 95(A) to 95(C) show the "return initial state" in which the rotating shaft 15 has rotated 45 degrees counterclockwise from the "45° return rotation state." In this state, as shown in Figure 95(A), the rotating shaft 15 has rotated 45 degrees counterclockwise together with the rotating disk 14 from the "45° return rotation state," and as shown in Figures 95(B) and 95(C), the shaft protrusion 15b has lowered into the disk recess 13e, lifting the rotating shaft 15 down. In this state, as shown in Figure 95(B), the shaft protrusion 15b fits into and engages with the disk recess 13e.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 1 of this embodiment described above, the top 15e of the shaft convex portion 15b and the top 13h of the disk convex portion 13g each form a convex curved surface, so that when the rotating shaft 15 lifts up and the top 15e of the shaft convex portion 15b rides on the top 13h of the disk convex portion 13g, as shown in Figures 92 (B) and 94 (B), they engage stably, thereby avoiding sudden changes in the rise and fall of the shaft convex portion 15b.

Ninth Embodiment
Next, the ninth embodiment will be described in detail with reference to FIGS.

[Regarding engaging and engaged structures]
This embodiment is a modification of the eighth embodiment, and differs from the eighth embodiment in the configurations of the engaging structure K1 and the engaged structure K2.

Figures 96 to 98 relate to the flow path switching device 1 of this embodiment. Figure 96 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted down before flow path switching. Figure 97 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted up during flow path switching. Figure 98 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted up during flow path switching. As shown in Figures 96 to 98, in this embodiment, the apex 15e of the shaft protrusion 15b and the apex 13h of the disk protrusion 13g each form a convex curved surface, and the bottom of the disk recess 13e forms a concave curved surface. In this embodiment, the radius of the convex curved surface of the apex 15e of the shaft protrusion 15b is smaller than the radius of the concave curved surface of the bottom of the disk recess 13e.

In contrast, Figures 99 to 101 relate to a comparative example (eighth embodiment), where Figure 99 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted down before switching the flow path, Figure 100 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted up during flow path switching, and Figure 101 is an image diagram showing the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted up during flow path switching.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 1 of this embodiment described above, as shown in FIGS. 96 to 98 , the radius of the convex curved surface of the shaft protrusion 15b is smaller than the radius of the concave curved surface of the disk recess 13e. Therefore, when the rotating shaft 15 begins to lift up from the state shown in FIG. 96 , i.e., at the beginning of flow path switching when the rotating shaft 15 begins to rotate to switch the flow path, the sliding resistance of the shaft protrusion 15b against the disk recess 13e is smaller than that of the comparative example shown in FIG. 99 . Comparing the case shown in FIG. 97 with the case shown in FIG. 100 , the sliding resistance is approximately the same in both cases. Furthermore, comparing the case shown in FIG. 98 with the case shown in FIG. 101 , the sliding resistance is also approximately the same in both cases. Therefore, the driving torque of the rotating shaft 15 can be reduced at the beginning of flow path switching, and the lift angle when the rotating shaft 15 begins to lift up can be reduced. Furthermore, since the lift angle when the rotating shaft 15 starts to lift up can be reduced, the driving torque of the rotating shaft 15 can be suppressed.

Figure 102 shows a graph of the relationship between changes in rotation shaft angle and changes in drive torque. In Figure 102, the thick line BL represents this embodiment, and the dashed line DL represents the comparative example (eighth embodiment). As shown in Figure 102, in this embodiment, the drive torque when the rotation shaft angle is "0°" is lower than that of the comparative example, and the drive torque when the rotation shaft angle is "45°" is higher than that of the comparative example.

Tenth Embodiment
Next, the tenth embodiment will be described in detail with reference to FIGS.

[Regarding the problem of the ninth embodiment]
In the ninth embodiment, the top 15e of the shaft protrusion 15b and the top 13h of the disk protrusion 13g each have a convex curved surface, and the bottom of the disk recess 13e has a concave curved surface. Furthermore, the radius of the convex curved surface of the top 15e of the shaft protrusion 15b is smaller than the radius of the concave curved surface of the bottom of the disk recess 13e. Therefore, when the rotating shaft 15 is lifted down and the shaft protrusion 15b rests on the disk recess 13e, the top 15e of the shaft protrusion 15b and the bottom of the disk recess 13e come into contact at a single point. In this state, the contact pressure of each seal member 17, 18 with the upper housing 11 and fixed disk 13 is maximized, resulting in high stress acting at the contact point between the top 15e of the shaft protrusion 15b and the bottom of the disk recess 13e.

Therefore, when the rotating shaft 15 begins to rotate in order to lift it up from a lift-down state, the top 15e of the shaft protrusion 15b and the bottom of the disk recess 13e begin to slide against each other at a single point, increasing sliding resistance and raising concerns about accelerated wear between the two 15b and 13e. As wear progresses at the top of the shaft protrusion 15b or the bottom of the disk recess 13e, the gap between the rotating disk 14 and the fixed disk 13 narrows, further increasing the contact surface pressure of each seal member 17, 18 and further increasing sliding resistance. As a result, the drive torque required to lift the rotating shaft 15 up when it begins to rotate increases, necessitating a high output from the drive unit 4. Therefore, in this embodiment, the shapes of the engaging structure and engaged structure (shaft protrusion 15b and disk recess 13e) have been improved as follows to reduce the drive torque required to lift the rotating shaft 15 up from a lift-down state.

[Regarding engaging and engaged structures]
Figures 103 to 113 show, in an image diagram, the change in the relationship between the engaging structure and the engaged structure when the rotating shaft 15 is lifted up from a lift-down state and then lifted down again during flow path switching in the flow path switching device 1 of this embodiment.

Figure 103 shows the relationship between the engaging structure and the engaged structure in the lift-down state before flow path switching, and Figure 104 shows an enlarged view of the ground contact portion of Figure 103. As shown in Figures 103 and 104, the disk recess 13e in this embodiment has a V-shaped gently inclined concave surface (gentle concave inclined surface) 13ea at its bottom, and a steeply inclined surface 13ia that continues from the gentle inclined concave surface 13ea to the disk protrusion 13g and forms the side surface 13i of the disk protrusion 13g. In this embodiment, the top 13h of the disk protrusion 13g forms a convex curved surface. Furthermore, the shaft protrusion 15b has a V-shaped gently inclined convex surface (convex gently inclined surface) 15ea at its top 15e that matches and can come into surface contact with the gently inclined concave surface 13ea, and the side surface 15d of the shaft protrusion 15b that continues from the gently inclined convex surface 15ea has a steeply inclined surface 15da that matches and can come into surface contact with the steeply inclined surface 13ia of the side surface 13i of the disk protrusion 13g.

In this state before the flow path is switched, the contact surface pressure of each seal member 17, 18 against the upper housing 11 and fixed disk 13 is high, and the contact surface pressure between the shaft convex portion 15b and the disk concave portion 13e is also high. However, because the concave gently inclined surface 13ea and the convex gently inclined surface 15ea are in contact with each other, the stress of the high contact surface pressure is dispersed rather than being concentrated at one point.

Next, Figure 105 shows the relationship between the engaging structure and the engaged structure at the start of flow path switching (initial drive when lift-up begins). During this initial drive, the convex gently inclined surface 15ea contacts the concave gently inclined surface 13ea, and the steeply inclined surface 15da of the shaft convex portion 15b contacts the steeply inclined surface 13ia of the disk convex portion 13g, sliding together. At this time, each seal member 17, 18 is subjected to high surface pressure, and the contact surface pressure between the shaft convex portion 15b and the disk concave portion 13e increases. However, because the concave gently inclined surface 13ea and the convex gently inclined surface 15ea are in contact with each other, and the steeply inclined surface 13ia and the steeply inclined surface 15da are in contact with each other, the stress of the high contact surface pressure is dispersed.

Next, Figure 106 shows the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up). During this lift-up, the steeply inclined surface 15da of the shaft protrusion 15b slides against the steeply inclined surface 13ia of the disk recess 13e while in contact with it. At this time, the rotating shaft 15 begins to lift up (the fixed disk 13 begins to descend), and the gap between the upper housing 11 and fixed disk 13 relative to the rotating disk 14 increases, reducing the contact surface pressure of each seal member 17, 18 to a moderate level.

Next, Figure 107 shows the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up). During this lift-up, the gently sloping convex surface 15ea of the shaft convex portion 15b slides against the convex curved apex 13h of the disk convex portion 13g while in contact with it. Figure 108 shows an enlarged view of the contact area in Figure 107. At this time, the rotating shaft 15 lifts up (the fixed disk 13 descends), further increasing the gap between the upper housing 11 and fixed disk 13 relative to the rotating disk 14, further reducing the contact surface pressure of each seal member 17, 18 to a low surface pressure. This reduces the load on the apex 13h of the disk convex portion 13g, and although the contact stress of the shaft convex portion 15b against the apex 13h of the disk convex portion 13g is concentrated, the stress is reduced.

Next, Figure 109 shows the relationship between the engaging structure and the engaged structure during flow path switching, immediately after the apex 15e of the shaft protrusion 15b passes over the apex 13h of the disk protrusion 13g (when lift-down begins). Figure 110 shows an enlarged view of the contact area in Figure 109. At the beginning of this lift-down, as in Figures 107 and 108, the gently sloping convex surface 15ea of the shaft protrusion 15b slides against the curved surface of the apex 13h of the disk protrusion 13g while in contact with it. At this time, the rotating shaft 15 begins to lift down (the fixed disk 13 begins to rise). However, because the gap between the upper housing 11 and the fixed disk 13 relative to the rotating disk 14 has widened, the contact surface pressure of each seal member 17, 18 is reduced to a low surface pressure. Therefore, as in Figures 107 and 108, although the contact stress of the shaft protrusion 15b against the apex 13h of the disk protrusion 13g is concentrated, this stress is reduced.

Next, Figure 111 shows the relationship between the engaging structure and the engaged structure during flow path switching (during lift-down). During this lift-down, the steeply inclined surface 15da of the shaft protrusion 15b slides against the steeply inclined surface 13ia of the disk recess 13e while in contact with it. At this time, the rotating shaft 15 is in the middle of lift-down (while the fixed disk 13 is rising), and the gap between the upper housing 11 and fixed disk 13 relative to the rotating disk 14 is decreasing, so the contact surface pressure of each seal member 17, 18 begins to increase and becomes moderate.

Next, Figure 112 shows the relationship between the engaging structure and the engaged structure before the flow path switching is complete (before lift-down is complete). Before lift-down is complete, the convex gently inclined surface 15ea contacts the concave gently inclined surface 13ea, and the steeply inclined surface 15da of the shaft convex portion 15b contacts the steeply inclined surface 13ia of the disk convex portion 13g, sliding together. At this time, each seal member 17, 18 is subjected to high surface pressure, and the contact surface pressure between the shaft convex portion 15b and the disk concave portion 13e increases. However, because the concave gently inclined surface 13ea and the convex gently inclined surface 15ea come into contact with each other, and the steeply inclined surface 13ia and the steeply inclined surface 15da come into contact with each other, the stress of the high contact surface pressure is dispersed.

Next, Figure 113 shows the relationship between the engaging structure and the engaged structure when flow path switching is complete (lift-down completion phase). When lift-down is complete, the surface pressure of each seal member 17, 18 increases further, and the contact surface pressure between the shaft convex portion 15b and the disc concave portion 13e also increases. However, since the concave gently inclined surface 13ea and the convex gently inclined surface 15ea come into contact with each other, the stress of the high contact surface pressure is dispersed.

[Operation and effect of the flow path switching device]
According to the configuration of the flow path switching device 1 of this embodiment described above, when the rotating shaft 15 is lifted down before flow path switching, the shaft protrusion 15b of the rotating shaft 15 engages with the disk recess 13e of the fixed disk 13, and the convex gently inclined surface 15ea of the shaft protrusion 15b comes into contact with the concave gently inclined surface 13ea of the disk recess 13e. When the rotating shaft 15 starts to rotate from this state to switch the flow path, the shaft protrusion 15b starts to slide against the disk recess 13e at a gentle slope due to the contact between the concave gently inclined surface 13ea and the convex gently inclined surface 15ea, and then slides due to the contact between the convex gently inclined surface 15ea and the concave gently inclined surface 13ea. Furthermore, as the rotation of the rotating shaft 15 progresses, the disk recess 13e and the shaft protrusion 15b transition from contacting the gently concave and gently inclined surfaces 13ea and 15ea to contacting the steeply inclined surfaces 13ia and 15da, causing them to slide against each other due to their surface contact. Therefore, when the rotating shaft 15 begins to rotate from a state in which the shaft protrusion 15b is engaged with the disk recess 13e, the drive torque required to rotate the rotating shaft 15 can be reduced, thereby suppressing wear on the shaft protrusion 15b and the disk recess 13e. Furthermore, the reduction in drive torque allows the drive unit 4 to be made more compact.

Eleventh Embodiment
Next, the eleventh embodiment will be described in detail with reference to FIGS. 114 and 115.

[Regarding engaging and engaged structures]
This embodiment is a modification of the tenth embodiment, and differs from the tenth embodiment in the configuration of the engaging structure and the engaged structure. Fig. 114 shows the relationship between the engaging structure and the engaged structure during flow path switching (during lift-up of the rotating shaft 15) in the flow path switching device 1 of this embodiment, in an image similar to Fig. 107. Fig. 115 shows an enlarged image of the ground contact portion in Fig. 114.

As shown in Figures 114 and 115, the top 13h of the disk protrusion 13g in this embodiment is not a convex curved surface, but rather a V-shaped convex gently sloping surface 13ha, similar to the top 15e of the shaft protrusion 15b. Therefore, during this lift-up, the convex gently sloping surface 15ea of the shaft protrusion 15b slides against the convex gently sloping surface 13ha of the top 13h of the disk protrusion 13g in a face-to-face contact state. Therefore, compared to the tenth embodiment, the contact stress between the shaft protrusion 15b and the disk protrusion 13g can be alleviated, suppressing wear on both 15b and 13g.

<Another embodiment>
The disclosed technology is not limited to the above-described embodiments, and can be implemented by appropriately modifying part of the configuration within the scope of the disclosed technology.

(1) In the first embodiment, the flow path switching device 1 is configured as an eight-way valve, but it is not limited to this and can also be configured as other multi-way valves such as a three-way valve, a four-way valve, or a six-way valve. Therefore, it is sufficient for the rotating disk 14 to have at least one rotating communication passage 40, and for the fixed disk 13 to have multiple fixed communication passages 50.

(2) The "sliding resistance reduction structure" in the first embodiment is an example and is not limited to the engaging structure K1 and engaged structure K2 described above.

(3) In the second embodiment, only the top 15e of the shaft protrusion 15b is formed into a convex curved surface. However, it is also possible to form only the top 13h of the disk protrusion 13g into a convex curved surface, or to form both the top 15e of the shaft protrusion 15b and the top 13h of the disk protrusion 13g into a convex curved surface.

(4) In the second embodiment, the top 15e of the shaft protrusion 15b is formed as a convex curved surface, but this top can also be formed as a flat surface.

This disclosed technology can be used, for example, to switch the flow path of a fluid in a fluid circuit through which a fluid such as a refrigerant flows.

1 Flow path switching device 2 Housing 3 Valve body portion 4 Drive portion (drive means)
5. Control unit (control means)
8 Flow path switching device 13 Fixed disk 13e Disk recess 13ea Recessed gently inclined surface 13g Disk protrusion 13h Top 13ha Convex gently inclined surface 13i Side surface 13ia Steeply inclined surface 14 Rotating disk (drive disk)
15 Rotating shaft 15a Tip portion 15b Shaft convex portion 15c Shaft concave portion 15d Side portion 15da Steep inclined surface 15e Top portion 15ea Convex gently inclined surface 17 Upper seal member 18 Lower seal member 20 Inflow passage (communication passage)
28 Gap 30 Outlet flow path (communication path)
40 Rotational communication passage (communication passage)
50 Fixed communication path (communication path)
X-axis direction

Claims (8)

Housing and
a valve body portion disposed inside the housing,
the valve body portion includes a fixed disk, a drive disk stacked on the fixed disk and rotating relative to the fixed disk, and a rotation shaft for rotating the drive disk,
the housing, the fixed disk, and the drive disk each have a plurality of communication passages, and the communication passages are connected as the drive disk rotates to form a fluid flow path;
In the flow path switching device, a seal member is provided in the flow path to suppress leakage of the fluid at least between the fixed disk and the drive disk,
a tip end of the rotary shaft is provided so as to be able to come into contact with and engage with the fixed disk,
The flow path switching device is characterized in that the fixed disk is configured to be able to move back and forth in the axial direction by abutting and engaging with the tip of the rotating shaft as it rotates. The flow path switching device according to claim 1,
the tip end of the rotating shaft includes a shaft protrusion and a shaft recess that are arranged in a circumferential direction,
the fixed disk includes a disk recess and a disk protrusion that can come into contact with and engage with the shaft protrusion and the shaft recess,
The flow path switching device, wherein the shaft protrusions, the shaft recesses, the disk recesses, and the disk protrusions each include a side surface that is inclined in a circumferential direction. The flow path switching device according to claim 2,
A flow path switching device characterized in that the top of at least one of the shaft convex portion and the disk convex portion is formed as a flat surface or a convex curved surface, and the bottom of at least one of the disk concave portion and the shaft concave portion is formed as a flat surface or a concave curved surface. The flow path switching device according to claim 2,
the disk recess has a V-shaped gently inclined concave surface at its bottom, and a steeply inclined surface that continues from the gently inclined concave surface to the disk protrusion and forms the side surface of the disk protrusion,
A flow path switching device characterized in that the shaft convex portion has a convex gently inclined surface at its top that aligns with the concave gently inclined surface and forms a V shape, and the side portion of the shaft convex portion that continues from the convex gently inclined surface has a steeply inclined surface that aligns with the steeply inclined surface of the side portion of the disk convex portion. 5. The flow path switching device according to claim 1,
The flow path switching device is characterized in that the drive disk and the rotary shaft are connected to each other so as to be relatively movable in the rotational direction and the axial direction. The flow path switching device according to claim 5,
The flow path switching device is characterized in that a connection portion between the rotary shaft and the drive disk has a gap in the rotation direction. The flow path switching device according to claim 6,
a switching angle at which the drive disk is rotated to switch the flow paths, the switching angle being set to the same angle as the rotation angle at which the rotating shaft rotates in the gap when the tip of the rotating shaft moves from the state in which it is engaged with the fixed disk to the state in which it is abutting the fixed disk. The flow path switching device according to claim 7,
a driving means for driving the rotation shaft;
a control means for controlling the driving means,
The control means controls the drive means to rotate the rotating shaft, switching the flow path with the tip of the rotating shaft abutting the fixed disk, and then rotate the rotating shaft in the opposite direction, stopping the rotation of the rotating shaft with the tip of the rotating shaft engaged with the fixed disk.