JP7577415B2 - Mechanical seal - Google Patents

Description

The present invention relates to a mechanical seal that has a flow path for circulating a fluid between the periphery of a sliding component and the outside of the mechanical seal.

Seals are used in a variety of fields to prevent leakage and mixing of sealed fluids. One example of such a seal is a shaft seal device capable of sealing the rotating shaft of a rotating machine in automobiles, general industrial machinery, etc. Among these, mechanical seals in particular are used in a wide range of fields because they can seal high-pressure sealed fluids.

Mechanical seals are constructed with a pair of annular sliding parts that can rotate relative to one another, and the sliding surfaces of the sliding parts slide closely against each other as the rotating shaft rotates, preventing leakage of the sealed fluid. Some such mechanical seals are capable of circulating fluid using a flow path that connects the periphery of the sliding parts to the outside of the mechanical seal. Some use such a flow path to, for example, discharge wear powder generated by the sliding of the sliding parts against each other using the fluid flowing through the flow path.

One example of such a mechanical seal is shown in Patent Document 1, where the flow path that guides the fluid to the outside is composed of a radially penetrating communication passage formed in the stationary seal ring, a through hole that linearly penetrates the housing in the radial direction, and a pipe that is inserted into the through hole and connected to the communication passage of the stationary seal ring so that it can communicate with it. This makes it possible to drain the wear powder generated by the close sliding of the rotating seal ring and the stationary seal ring by passing it through the flow path together with the sealed fluid and discharging it by connecting a suction pump connector to the opening of the pipe on the outside of the machine and sucking it.

Patent No. 5593519 (page 8, figure 1)

In mechanical seals with flow paths that allow fluid to flow between the periphery of the sliding parts and the outside of the mechanical seal, the direction of fluid flow, the position of the through holes in the housing, and the layout of the flow paths are set in relation to the surrounding equipment and facilities. However, when a structure is adopted in which a linear through hole is formed in the housing and the fluid is guided through a pipe, as in Patent Document 1, the layout and shape of the flow paths are restricted, there is little freedom in designing the direction of the opening of the flow path that opens to the outside, and the configuration and assembly of the flow paths are complicated.

The present invention was made with an eye on these problems, and aims to provide a mechanical seal that allows for easy assembly of flow paths with a high degree of design freedom.

In order to solve the above problems, the mechanical seal of the present invention comprises:
A mechanical seal having a flow passage, one end of which is open to the outside of the aircraft and the other end of which is open near a stationary seal ring and a rotating seal ring,
The housing of the mechanical seal includes a main body and a block body made of a non-metallic material inserted into a through-hole or a recess formed in the main body,
The block body has a through passage formed therein for guiding a fluid, the through passage constituting at least a part of the flow path.
According to this, since the through passage constituting the flow passage can be formed in advance in the block body which is separate from the main body of the housing, the opening direction of the flow passage to the outside of the machine can be freely designed and the flow passage can be easily assembled. In addition, since the block body in which the through passage is formed is made of a non-metallic material, it can be used as a flow passage made of a non-metallic material.

The through passage of the block body may have an opening on the one end side that is open in the axial direction of the housing.
According to this, it is possible to connect the through passage to the outside of the machine on the inner diameter side of the outer diameter end of the housing, so that the radial dimension of the mechanical seal can be reduced.

The through passage of the block body may have an opening on the other end side that is open to a radially inner diameter side of the housing.
This allows the structure communicating with the inside of the housing to be configured simply.

The stationary seal ring has a communication passage that constitutes a part of the flow passage,
The through passage of the block body and the communication passage of the stationary seal ring may be communicated in a sealed state from an outside of a seal means provided between the block body and the stationary seal ring.
This makes it possible to configure a flow path that allows fluid to flow around the stationary seal ring and the rotary seal ring in a simple and compact manner.

The sealing means may be constituted by a pipe made of a non-metallic material that is fitted into the block body and the stationary seal ring, and a seal member that is attached to the outer periphery of the pipe.
This makes it possible to easily establish communication between the communication passage and the through passage.

The through passage of the block body may have a connector through which a fluid can pass connected to the opening on the one end side.
According to this, since the fluid can pass directly between the connector and the through passage, it is possible to reliably prevent metal ions from eluting into the fluid passing through the connector and the through passage.

The block body may be formed in a columnar shape.
This facilitates the relative alignment of the main body and the block body.

The block body may be made of a resin material.
According to this, the block body can be press-fitted into the through-hole or recess of the main body and fixed thereto.

1 is a perspective view showing a part of a mechanical seal to which a non-metallic flow passage according to a first embodiment of the present invention is applied, in which a part of the mechanical seal is cut away. 1 is a cross-sectional view of a flow passage made of a non-metallic material according to a first embodiment of the present invention. 4A to 4C are diagrams for explaining an assembly procedure of a flow passage made of a non-metallic material according to the first embodiment of the present invention. 5A to 5C are diagrams for explaining the procedure for assembling the non-metallic flow passage of the first embodiment, following FIG. 3 . 5 is a diagram for explaining the procedure for assembling the non-metallic flow passage of the first embodiment, following FIG. 4 . 5A to 5C are diagrams for explaining the procedure for assembling the non-metallic flow passage of the first embodiment. FIG. 6 is a cross-sectional view of a flow passage made of a non-metallic material according to a second embodiment of the present invention. FIG. 11 is a cross-sectional view of a flow passage made of a non-metallic material according to a third embodiment of the present invention. 4 is a cross-sectional view of another embodiment of a non-metallic flow passage according to the present invention; FIG.

The following describes, based on examples, how to implement a mechanical seal according to the present invention that has a flow path made of a non-metallic material.

A mechanical seal having a non-metallic flow passage according to the first embodiment will be described with reference to Figs. 1 to 6. Below, the top and bottom of Fig. 2, as viewed from the front, will be described as the top and bottom of the mechanical seal. In particular, the top of the page will be described as the top of the mechanical seal, and the bottom of the page will be described as the bottom of the mechanical seal. In this first embodiment, the inner diameter side of the sliding surfaces of the pair of sliding parts that make up the mechanical seal will be described as the sealed fluid side, and the outer diameter side as the atmosphere side.

The mechanical seal M for rotary machines shown in Figure 1 is an outside type that seals against leakage of high-pressure sealed fluid F from the inner diameter side to the atmosphere A on the outer diameter side, and is applied to rotary machines used in the manufacture of semiconductor products, food, medicines, etc. In addition, a flow path 3 made of a non-metallic material is configured, and a suction pump (not shown) is used to discharge wear powder together with the sealed fluid F through a connector 9 connected to the end of the flow path 3. The sealed fluid F may be either liquid or gas.

As shown in Figures 1 and 2, the mechanical seal M is mainly composed of a rotating seal ring 20 as an annular sliding part that is rotatable together with the rotating shaft 1, a stationary seal ring 10 as an annular sliding part that is non-rotating, and a housing 5 that holds the stationary seal ring 10 in a non-rotating state against the case of the rotating machine. The rotating seal ring 20 is biased in the axial direction by a coil spring (not shown), so that the sliding surface 11 of the stationary seal ring 10 and the sliding surface 21 of the rotating seal ring 20 slide closely against each other.

The mechanical seal M has a stationary seal ring 10 fixed to the inner diameter side and axially lower side of the housing 5, in other words, the inner side S1 of the housing 5.

The rotating seal ring 20 is formed in an annular shape from filled PTFE (Polytetrafluoroethylene), and the stationary seal ring 10 is formed in an annular shape from silicon carbide. In other words, both the stationary seal ring 10 and the rotating seal ring 20 are formed from non-metallic materials. The material of the stationary seal ring 10 and the rotating seal ring 20 may be changed as appropriate, as long as it is a non-metallic material such as ceramic, synthetic resin, or carbon.

The rotary seal ring 20 is fitted onto the collar 22 and is rotatable together with the rotary shaft 1 and can move axially relative to the rotary shaft 1. Specifically, the sleeve 2 is provided in a state in which it can rotate together with the rotary shaft 1, the collar 22 is fixed to the sleeve 2, the drive bolt 23 is inserted into a through hole in the collar 22 and screwed to the spring receiving part 24, a coil spring (not shown) is disposed between the collar 22 and the spring receiving part 24 to bias them relatively in the direction away from each other, the spring receiving part 24 receives the biasing force of the coil spring and presses the rotary seal ring 20 toward the stationary seal ring 10, and the drive pin 25 is inserted and fixed into the slits of the spring receiving part 24 and the rotary seal ring 20 to restrict the relative rotation of the two.

The stationary seal ring 10 has a communication passage 12 formed at one point in the circumferential direction, penetrating it in the radial direction. The communication passage 12 is composed of a small diameter hole portion 13 that extends linearly from the inner diameter end to the outer diameter side, and a large diameter hole portion 14 that is continuous with the small diameter hole portion 13 and extends linearly to the outer diameter end.

The foreign object receiving member 30, which is a circular ring formed in an L-shape in cross section, is press-fitted into the stationary seal ring 10 from the axially lower side. More specifically, the convex portion 31 and the flange 32 of the foreign object receiving member 30 sandwich the convex portion 15 of the stationary seal ring 10 from above and below, thereby restricting the vertical movement of the foreign object receiving member 30. The space between the cylindrical portion 33 extending in the axial direction of the foreign object receiving member 30 and the stationary seal ring 10 and the rotating seal ring 20 constitutes a foreign object receiving portion 35, which is part of the space on the sealed fluid F side.

In addition, since the upper end of the cylindrical portion 33 is located axially above the sliding surfaces 11, 21 of the stationary seal ring 10 and the rotating seal ring 20, i.e., on the rotating seal ring 20 side, the wear powder generated by the close sliding of the sliding surfaces 11, 21 against each other can be prevented from crossing the cylindrical portion 33 and entering the main portion of the sealed fluid F, and the wear powder can be collected in the foreign matter receiving portion 35.

The communication passage 12 of the stationary seal ring 10 is connected to the foreign object receiving portion 35 through the opening 13a of the small diameter hole portion 13. Here, the opening 13a of the communication passage 12 is the opening at the other end of the flow path in the present invention.

The housing 5 is composed of a main body 50 integrally formed in an annular shape from a metal material, and a columnar block body 6 integrally formed in an approximately rectangular parallelepiped shape from a resin material, PEEK (Polyetheretherketone). The block body 6 may be formed from a resin material other than PEEK, such as PTFE, or may be formed from ceramics, etc., as long as it is formed from a non-metallic material. Furthermore, if it is formed from a resin material, it is preferable that a reinforcing material such as glass fiber or carbon fiber is blended into it.

The main body 50 has a rectangular cross-sectional through-hole 51 that penetrates the axial direction at one point in the circumferential direction, and an annular recess 52 is formed on the axially lower part and inner diameter side into which the outer diameter end of the stationary seal ring 10 can be inserted, and the lower end and inner diameter side of the through-hole 51 communicates with the annular recess 52.

The block body 6 is inserted into the through-hole 51. More specifically, the cross-sectional area of the block body 6 in the radial direction of the housing 5 is formed to be approximately the same as or slightly smaller than the cross-sectional area of the through-hole 51 of the main body 50, so that the block body 6 is inserted into the through-hole 51.

The block body 6 is perforated with a perforating tool to form an inverted L-shaped through passage 60 in cross section. The through passage 60 is composed of a small diameter hole portion 61 formed in an inverted L-shaped cross section, an inner large diameter hole portion 62 connected to the inner diameter side end of the small diameter hole portion 61, and an outer large diameter hole portion 63 connected to the axial upper end of the small diameter hole portion 61. The through passage 60 may be formed by various methods other than perforation, such as casting or die-cutting. The block body may be formed by combining multiple divided members, but is preferably molded as a single piece in consideration of the sealing properties of the through passage.

The opening 62a of the inner large diameter hole portion 62 is open to and communicates with the inside S1 of the housing 5, and the opening 63a of the outer large diameter hole portion 63 is open to and communicates with the outside S2 of the housing 5. Here, the opening 62a is the opening on the other end side of the through passage in the present invention, and the opening 63a is the opening on one end side of the through passage in the present invention.

The outer large diameter hole 63 has a female thread 64 formed at its axial upper end, which allows a male thread formed at the tip of the connector 9 to be screwed into it. The opening 63a of the outer large diameter hole 63 is open to the outside S2 of the housing 5, and is an opening at one end of the flow path in the present invention, which is connected through the connector 9 to the inside of a suction pump (not shown) located outside the mechanical seal M.

The stationary seal ring 10 and the block body 6 are connected by a cylindrical pipe 80 made of a resin material and O-rings 81 fitted onto both axial ends of the pipe 80. More specifically, the end of the pipe 80 located on the stationary seal ring 10 side is press-fitted and fixed together with the O-ring 81 into the large diameter hole 14 of the stationary seal ring 10, and the end of the pipe 80 located on the block body 6 side is press-fitted and fixed together with the O-ring 81 into the inner large diameter hole 62 of the block body 6.

As a result, the communication passage 12 of the stationary seal ring 10 and the through passage 60 of the block body 6 are connected through the through passage 80a of the pipe 80, and the gap between the stationary seal ring 10 and the block body 6 is sealed, forming a flow passage 3 made of a non-metallic material. Here, the pipe 80 and each O-ring 81 are the sealing means in this invention, and the O-ring 81 is the sealing member in this invention.

Next, the assembly procedure for the mechanical seal M, particularly the non-metallic flow passage 3, will be described with reference to Figures 2 to 6. In this description, the communication passage 12 of the stationary seal ring 10, the through passage 80a of the pipe 80, and the through passage 60 of the block body 6 are formed in advance before assembling the flow passage 3.

First, as shown in FIG. 3, the end of the pipe 80 located on the sealed fluid F side is press-fitted into the large diameter hole 14 of the stationary seal ring 10 together with the O-ring 81 (see FIG. 2).

Next, the axis of the inner large diameter hole 62 (see FIG. 2) of the block body 6 is aligned with the axis of the atmospheric A side end of the pipe 80, and the block body 6 is pushed into the pipe 80. As a result, the atmospheric A side end of the pipe 80 is pressed into the inner large diameter hole 62 of the block body 6 together with the O-ring 81, and the block body 6 is connected and held to the stationary seal ring 10 as shown in FIG. 4.

In this state, the flat surface 6a (see FIG. 6) of the opposing block body 6 is in face-to-face contact with the flat surface 10a of the stationary seal ring 10. In this way, the flat surface 6a of the block body 6 is in face-to-face contact with the flat surface 10a of the stationary seal ring 10, so that relative positioning is achieved, making positioning easy. Note that the stationary seal ring may not have a flat surface, and the block body may have a concave curved surface that comes into contact with the curved outer peripheral surface of the stationary seal ring.

Then, while inserting the block body 6 into the through-hole 51 of the main body 50 from the axially upward side, the main body 50 is pushed toward the block body 6 and the stationary seal ring 10, and the main body 50 is fitted onto the stationary seal ring 10 as shown in FIG. 5. At this time, the stationary seal ring 10 abuts against the inner peripheral surface of the axially upper side of the annular recess 52 of the main body 50 (see FIG. 2), so that the stationary seal ring 10 and the main body 50 are relatively aligned in the axial direction. To explain this procedure in more detail, first align the through-hole 51 of the main body 50 with the block body 6.

At this time, referring to FIG. 3, the large diameter hole portion 14 of the stationary seal ring 10 and the inner large diameter hole portion 62 of the block body 6 are each cylindrical spaces, so that the block body 6 can be rotated in the circumferential direction of the pipe 80. This makes it easy to align the axis of the through portion 51 of the main body 50 with the axis of the block body 6.

In addition, because the block body 6 is held by the stationary seal ring 10 via the pipe 80 and each O-ring 81, there is no need to hold the block body 6 by hand or take other measures to prevent the block body 6 from moving, and the block body 6 can be easily inserted into the through-hole 51 of the main body 50.

Next, the bolt 53 is screwed into the female thread of the main body 50 from below, and as shown in FIG. 6, the head 54 of the bolt 53 is partially accommodated in the recess formed in the underside of the main body 50 and the block body 6, and the male thread end face of the head 54 is abutted across the axial underside 50d of the main body 50 and the axial underside 6d of the block body 6. This prevents the block body 6 from coming loose. In this way, the assembly of the flow path 3 is completed.

In addition, the block body 6 is inserted in a state where it is surrounded on all four sides by the flat surface 10a of the stationary seal ring 10 (see Figure 3) and the peripheral wall 50a of the main body 50, so it is prevented from coming out in a direction perpendicular to the axis of the through-hole 51.

The assembly procedure for the flow path 3 is not limited to the above and may be modified as appropriate.

As described above, in the flow path 3 of this embodiment 1, the through passage 60 that constitutes the flow path 3 can be formed in advance in the block body 6 that is separate from the main body 50 of the housing 5, so the opening direction of the flow path 3 toward the outside S2 of the housing 5 can be freely designed, and the flow path 3 can be easily assembled. Therefore, the flow path 3 can be easily designed and arranged to match the layout shape of the surrounding equipment and facilities.

More specifically, the through passage 60 is not limited to an inverted L-shaped through passage 60 in cross section, but may be a straight through passage, a crank-shaped through passage, etc., and can be easily modified as appropriate as long as the shape can be formed in the block body 6.

Furthermore, regardless of the shape of the through passage, as long as the block body 6 can be inserted and placed in the through-hole 51 of the main body 50, the housing 5 having a through passage can be formed by inserting the block body 6 into the through-hole 51. Therefore, compared to a configuration in which a pipe formed to match the shape of the through-hole formed in the housing is inserted, if the through passage can be formed in the block body 6, a continuous through passage can be formed without seams, providing a high degree of design freedom. It goes without saying that the opening direction on one side of the through passage and the opening direction of the through-hole or recess in the main body are approximately the same direction.

In addition, since the block body 6 in which the through passage 60 is formed is made of a non-metallic material, it can be used as a flow path 3 made of a non-metallic material. This allows the mechanical seal M to be applied even to rotating machines such as pumps and mixers that handle substances used in semiconductor products, food, medicines, etc., where the elution of metal ions into the sealed fluid F is to be avoided.

The through-hole 51 of the main body 50 extends parallel to the axial direction of the housing 5 and opens to the outside S2 of the housing 5. The through-hole 60 of the block body 6 inserted into the through-hole 51 has an opening 63a of the outer large diameter hole portion 63 that opens in the axial direction of the housing 5. This makes it possible to connect the through-hole 60 to the outside S2 of the housing 5 on the inner diameter side of the outer diameter end of the housing 5, thereby making it possible to reduce the radial dimension of the mechanical seal M.

In addition, the opening 63a of the outer large diameter hole portion 63 of the through-hole 51 of the main body 50 is open to the axially upper side of the housing 5, i.e., to the side of the rotating seal ring 20 arranged opposite the stationary seal ring 10. Compared to a configuration in which the opening on one side of the through-hole is open to the axially lower side, for example, the axial dimension of the mechanical seal M can be utilized to allow for the dimensions of the connector 9. In other words, the axial dimension of the connector 9 when connected can be reduced.

In addition, the opening 62a of the inner large diameter hole portion 62 of the through passage 60 of the block body 6 is open to the radially inner diameter side of the housing 5. Therefore, compared to a case where the opening on the other side of the through passage is open in the axial direction of the housing, it is not necessary to provide a separate structure to connect the through passage 12 of the stationary seal ring 10 or the foreign object receiving portion 35, and the structure connecting the through passage to the inside S1 of the housing 5 can be configured simply.

In addition, the opening 62a of the inner large diameter hole portion 62 of the through passage 60 of the block body 6 is connected to the communication passage 12 of the stationary seal ring 10 through the through passage 80a of the pipe 80. Therefore, compared to a configuration in which, for example, no communication passage is formed in the stationary seal ring, and a passage is formed that extends around the stationary seal ring (see FIG. 9), it is easy to reduce the axial dimension of the mechanical seal M, and the structure for forming the passage 3 can be made compact.

Furthermore, the flow path 3 is formed by sealing the space between the stationary seal ring 10 and the block body 6, both of which are made of non-metallic materials, with the pipe 80 and each O-ring 81, preventing the fluid flowing through the flow path 3 from coming into contact with the main body 50. As a result, it is not necessary to line the main body 50 with a non-metallic material, as with the lining layer 305a shown in FIG. 9, for example, and the flow path 3 can be constructed simply and at low cost.

In addition, the sealing means of this embodiment 1 is composed of a pipe 80 and two O-rings 81, so the communication passage 12 and the through passage 60 can be easily connected.

In addition, since the connector 9 is connected to the outer large diameter hole portion 63 of the through passage 60, the fluid can be led from inside the flow path 3 into the connector 9 without coming into contact with the main body 50 made of a metal material. In other words, it is possible to reliably prevent metal ions from eluting into the fluid passing through the connector 9 and through passage 60. In addition, it is possible to omit the lining of the main body 50 with a non-metallic material. In other words, it is possible to construct the flow path 3 simply and at low cost.

In addition, because the block body 6 is formed in a columnar shape, it is easier to determine the direction of insertion into the main body 50 through-hole 51 compared to when it is formed in a cubic or spherical shape, for example. In particular, the block body 6 in this embodiment 1 is in the shape of a prism with a rectangular cross section, and has a rotation-stop function when the block body 6 is inserted into the through-hole 51, making it easy to align the main body 50 and the block body 6 relative to each other and stabilizing their position after assembly. Note that the block body 6 is not limited to a rectangular shape, as it can be stopped by its non-circular cross section, for example, if it is polygonal or elliptical.

In addition, since the block body 6 is made of a resin material, it may be fixed by pressing it into the through-hole 51 of the main body 50. This not only prevents the block body 6 from coming loose, but also makes it less likely for relative movement or vibration to occur with respect to the main body 50, thereby preventing wear on the block body 6.

In addition, the flow passage 3 is composed of the communication passage 12 of the stationary seal ring 10 made of a non-metallic material, the through passage 80a of the pipe 80 made of a resin material, and the through passage 60 of the block body 6 made of a resin material, so the structure is simpler than, for example, a configuration in which the inner surface of the communication passage formed in a stationary seal ring made of a metallic material is lined with a non-metallic material.

In addition, because the main body 50 of the housing 5 is integrally formed, there is no need to assemble it as a whole, compared to a housing constructed by connecting multiple separate parts, making assembly simpler and easier to increase the structural strength.

The block body 6 is inserted surrounded on all four sides by the flat surface 10a (see FIG. 3) of the highly rigid stationary seal ring 10 and the peripheral wall 50a of the highly rigid main body 50, ensuring its strength. In particular, the upper end of the block body 6, including the outer large diameter hole portion 63, is surrounded by the peripheral wall 50a of the main body 50, which is integrally formed, ensuring the strength of the outer large diameter hole portion 63 at the connection portion with the connector 9.

The stationary seal ring 10 also has a flat surface 10a, which is easier to machine than machining the end face of a block body to match the curvature of the outer peripheral surface of the stationary seal ring, for example.

In addition, the bolt 53 is screwed into the main body 50, which has a higher structural strength than the block body 6, so the fastening strength of the bolt 53 is high and the block body 6 is less likely to come loose.

Next, a second embodiment of a flow path made of a non-metallic material will be described with reference to FIG. 7. Note that a description of the same configuration as in the first embodiment will be omitted.

As shown in FIG. 7, the flow path 103 of the second embodiment is formed by the communication passage 12 of the stationary seal ring 10 and the through passage 60 of the block body 106. In addition, the gap between the stationary seal ring 10 and the block body 106 is sealed by an O-ring 181, which is a sealing means. As a result, the flow path 103 is formed with a smaller number of parts compared to the first embodiment.

The main body 150 of the housing 105 is formed with a recess 151 that is convex in cross section and penetrates in the axial direction at a portion of the circumference, and the block body 106 is formed with a convex cross section so that it can be inserted into the recess 151.

As a result, the annular end surface 106u of the block body 106 is brought into contact with the eaves 151a that protrude toward the center at the upper end of the recess 151, and the bolt 53 is screwed into the main body 150 in the same manner as in Example 1, thereby preventing the block body 106 from coming loose in the axial direction.

The flow passage 103 of this embodiment 2 can be assembled by inserting the block body 106 into the recess 151 of the main body 150 to assemble the housing 105, and then fitting the housing 105 onto the stationary seal ring 10 from the axially upward side. The main body 150 may also be fitted onto the stationary seal ring 10 from the axially upward side with the flat surface 10a of the stationary seal ring 10 and the flat surface 6a of the block body 106 in face-to-face contact.

The O-ring 181 is configured to be fitted into the large diameter hole 14 of the stationary seal ring 10, but this is not limited to the configuration, and it may be fitted into the inner large diameter hole 62 (see FIG. 2) formed in the block body 106. Furthermore, the O-ring 181 is not limited to being fitted into a cylindrical recess such as the large diameter hole 14 and the inner large diameter hole 62, and may be fitted into an annular groove, and the support shape may be changed as appropriate.

Next, a third embodiment of a flow path made of a non-metallic material will be described with reference to FIG. 8. Note that a description of the same configuration as in the first and second embodiments will be omitted.

As shown in FIG. 8, the flow passage 203 of the third embodiment is composed of the communication passage 12 of the stationary seal ring 10 and an arc-shaped through passage 160 that passes through the block body 206 from the inner diameter side to the outer diameter side while rounding in the circumferential direction.

The main body 250 of the housing 205 is formed with a recess 251 that is a convex shape facing sideways in cross section, which penetrates the housing 205 in the radial direction and has a reduced diameter on the outer diameter side end. The annular end face 206u of the block body 206 is abutted against the eaves 251a on the axial outer diameter side of the recess 251, and is fitted onto the stationary seal ring 10, thereby preventing the block body 206 from coming out in the radial direction.

Then, as in the first embodiment, the bolt 53 is screwed into the main body 250, and the inner circumferential surface of the recess 251 and the head 54 of the bolt 53 prevent the block body 206 from coming loose in the axial direction.

The O-ring 181 is configured to be fitted into the large diameter hole 14 of the stationary seal ring 10, but is not limited to this and may be fitted into the inner large diameter hole 62 (see Figure 2) formed in the block body 206.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

For example, in the above embodiment, the flow passages are described as being for discharging fluids and wear debris, but they are not limited to this. They may also be for supplying fluids for cooling, for heating, or for improving lubrication between sliding surfaces from outside the machine to the vicinity of the stationary and rotating seal rings, and may be modified as appropriate.

In addition, the vicinity of the stationary seal ring and the rotary seal ring has been described as a foreign object receiving portion, but this is not limited thereto, and may be, for example, the sealed fluid side other than the foreign object receiving portion, the atmospheric side, a coil spring, a drive pin, etc., or between the sliding surfaces of the stationary seal ring and the rotary seal ring, or may be changed as appropriate as long as it is inside the housing and in the vicinity of the stationary seal ring and the rotary seal ring. More preferably, it is the same space as the space in which the stationary seal ring and the rotary seal ring are arranged.

In addition, in the above embodiment, the block body is described as being provided at one location in the circumferential direction of the housing, but this is not a limitation, and the block body may be provided at multiple locations in the circumferential direction, and is not limited thereto.

In addition, although the stationary seal ring has been described as having a communicating passage formed therein, the present invention is not limited to this, and as shown in FIG. 9, the stationary seal ring 110 does not necessarily have to have a communicating passage formed therein. Specifically, by forming a through passage 360 along the shape of the block body 306 formed in an inverted L-shape in cross section and assembling the housing 305 together with the main body 350, it is possible to form a flow path using only the through passage 360 without increasing the number of parts. In such a configuration, it is preferable to form a lining layer 305a made of a non-metallic material on the main body 350 at locations that may come into contact with the fluid.

In addition, the rotating seal ring has been described as being made of a non-metallic material, but this is not limiting, and it may be made of a metallic material and then lined with a non-metallic material. This is also true for stationary seal rings, and if a communication passage is formed, the inner circumferential surface of the communication passage may also be lined with a non-metallic material.

In addition, while the block body has been described as being configured to have a connector connected thereto, this is not limiting, and the block body may be used as an opening through which fluid flows in and out without using a connector, for example by forming the bottom of a storage space in which fluid is stored.

In addition, the opening at one end of the flow path has been described as being an opening of the outer large diameter hole portion of the through passage, but this is not limited thereto, and it may be an opening of a flow path component separately assembled so as to be continuous with the outer large diameter hole portion, and may be modified as appropriate. Similarly, the opening at the other end of the flow path has been described as being an opening of the small diameter hole portion of the communication passage, but this is not limited thereto, and it may be an opening of a flow path component separately assembled so as to be continuous with the small diameter hole portion, and may be modified as appropriate.

The sealing means has been described as a pipe, an O-ring, etc., but is not limited to these and may be a gasket, adhesive, etc., and may be modified as appropriate.

In addition, the block body has been described as being inserted into the recess, but this is not limited thereto, and the block body may have a cross-sectional area larger than that of the recess, be press-fitted into the recess, or a seal member may be disposed between the block body and the inner peripheral surface of the recess to seal the gap therebetween, or may be modified as appropriate.

In addition, the main body has been described as being integrally formed, but this is not limited thereto, and it may be divided into multiple parts.

Reference Signs List 1 Rotating shaft 2 Sleeve 3 Flow passage 5 Housing 6 Block body 9 Connector 10 Stationary seal ring 12 Communication passage 13a Opening (opening at the other end)
20 Rotary seal ring 35 Foreign object receiving portion (near the stationary seal ring and the rotating seal ring)
50 Main body 51 Penetrating portion 60 Through passage 62a Opening (opening on one end side)
63 Outer large diameter hole portion 63a Opening (opening at one end, opening on one end side)
80 Pipe (sealing means)
81 O-ring (sealing means, sealing member)
103, 203 Flow path 105, 205 Housing 106, 206 Block body 150, 250 Main body 151, 251 Recess 160 Through passage 181 O-ring (sealing means)
305 Housing 306 Block body 350 Main body 360 Through passage (flow passage)
A Atmosphere F Sealed fluid M Mechanical seal S1 Inside S2 Outside

Claims (7)

A mechanical seal having a flow passage, one end of which is open to the outside of the machine and the other end of which is open to a sealed fluid side relative to the sliding surfaces of a stationary seal ring and a rotating seal ring,
The housing of the mechanical seal includes a main body and a block body made of a non-metallic material inserted into a through-hole or a recess formed in the main body,
The block body has a through passage for guiding a fluid, and the through passage constitutes at least a part of the flow path ,
The through passage of the block body is a mechanical seal in which the opening at one end is open in the axial direction of the housing . A mechanical seal having a flow passage, one end of which is open to the outside of the machine and the other end of which is open to a sealed fluid side relative to the sliding surfaces of a stationary seal ring and a rotating seal ring,
The housing of the mechanical seal includes a main body and a block body made of a non-metallic material inserted into a through-hole or a recess formed in the main body,
The block body has a through passage for guiding a fluid, and the through passage constitutes at least a part of the flow path ,
The stationary seal ring has a communication passage that constitutes a part of the flow passage,
a seal member provided between the block body and the stationary seal ring, the through passage of the block body and the communication passage of the stationary seal ring being communicated in a sealed state with respect to an outside of the seal member . The mechanical seal according to claim 2, wherein the sealing means is composed of a non-metallic pipe that is fitted into the block body and the stationary seal ring, and a sealing member that is attached to the outer periphery of the pipe. 4. The mechanical seal according to claim 1, wherein the through passage of the block body has an opening at the other end that opens toward a radially inner side of the housing. 5. The mechanical seal according to claim 1 , wherein the through passage of the block body has a connector through which a fluid can pass connected to the opening at one end. 6. The mechanical seal according to claim 1 , wherein the block body is formed in a columnar shape. 7. The mechanical seal according to claim 1 , wherein the block body is made of a resin material.

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