JP7645575B2 - Motor-operated valve - Google Patents

Description

The present invention relates to a motor-operated valve.

The motor-operated valve used as a flow control valve in the refrigeration cycle has a screw mechanism in which the male thread of the valve shaft, which is driven to rotate by a motor, is screwed into a female threaded hole in the valve body. This screw mechanism converts the rotational motion into axial motion, displacing the valve shaft in the axial direction and controlling the flow rate.

For example, Patent Document 1 discloses an electric valve in which a thin plate member (punched plate) with many small holes that perform a throttling function and a bubble-fragmenting function is attached to the main body and allows a refrigerant to pass through. Such a thin plate member performs the functions of straightening the refrigerant passing through in a two-phase flow state, throttling, and fragmenting the bubbles in the refrigerant in a two-phase flow state, and can effectively reduce the refrigerant passing noise caused by the bubbles.

JP 2007-107623 A

In the refrigeration cycle, the refrigerant generally flows from the pipes into the valve body of the motor-operated valve in a gas-liquid two-phase flow state, and so inherently contains air bubbles. In addition, when the refrigerant passes through the orifice, a pressure drop occurs, generating air bubbles. When these bubbles burst, they generate noise.

The motor-operated valve in Patent Document 1 can reduce the refrigerant passing noise caused by air bubbles, but there is room for further quieting.

The inventors discovered that in the motor-operated valve of Patent Document 1, when the refrigerant passes through the orifice, passes through the small hole in the thin plate member during the pressure recovery process, and enters the larger diameter pipe, turbulence occurs, generating noise. In addition, because the motor-operated valve of Patent Document 1 requires a thin plate member, there is also the problem that the number of parts increases and assembly is time-consuming.

The present invention aims to provide an electric valve that can further reduce noise while ensuring ease of assembly.

In order to solve the above problems, the motor-operated valve of the present invention comprises:
A valve body having a valve chamber;
a valve seat member provided on the valve body and having a valve seat;
a valve body disposed in the valve chamber and movable up and down in a direction toward or away from the valve seat,
the valve seat member includes an orifice portion adjacent to the valve seat and a flow straightening hole communicating with the orifice portion,
The valve seat member has a truncated cone portion, and an outlet of the flow straightening hole is formed on an outer circumferential surface of the truncated cone portion,
a central axis of the flow straightening hole is not parallel to and does not intersect with the axis of the orifice portion, and passes between an inner circumferential surface of the orifice portion and the axis of the orifice portion,
When the axis of the orifice portion is projected along the normal direction of a plane that includes the central axis of the flow straightening hole and is parallel to the axis of the orifice portion, the central axis of the flow straightening hole intersects with the projected axis of the orifice portion, and the projected axis toward the valve seat side and the central axis toward the tip side of the flow straightening hole form an obtuse angle on either side of the intersection.

The present invention provides an electrically operated valve that can further reduce noise while ensuring ease of assembly.

FIG. 1 is a vertical sectional view showing a motor-operated valve according to a first embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of the valve seat member according to the first embodiment. FIG. 3 is a perspective view of the valve seat member according to the first embodiment, as viewed from below. FIG. 4 is a bottom view of the valve seat member according to the first embodiment. FIG. 5 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the second embodiment. FIG. 6 is a bottom view of the valve seat member according to the second embodiment. FIG. 7 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the third embodiment. FIG. 8 is a bottom view of the valve seat member according to the third embodiment. FIG. 9 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the fourth embodiment. FIG. 10 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the fifth embodiment. FIG. 11 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the sixth embodiment. FIG. 12 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the seventh embodiment. FIG. 13 is a bottom view of the valve seat member according to the seventh embodiment. FIG. 14 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the eighth embodiment. FIG. 15 is a bottom view of the valve seat member according to the eighth embodiment. FIG. 16 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the ninth embodiment. FIG. 17 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the tenth embodiment. FIG. 18 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the eleventh embodiment. FIG. 19 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the twelfth embodiment. FIG. 20 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the thirteenth embodiment. FIG. 21 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the fourteenth embodiment. FIG. 22 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the fifteenth embodiment. FIG. 23 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the sixteenth embodiment. FIG. 24 is a vertical sectional view of a valve seat member that can be used in the motor-operated valve according to the seventeenth embodiment. FIG. 25 is a diagram showing a configuration in which a valve seat member and a porous filter that can be used in a motor-operated valve according to a modified example of this embodiment are combined.

The following describes an embodiment of the present invention with reference to the drawings.

[First embodiment]
FIG. 1 is a vertical cross-sectional view showing an electric valve 1 according to a first embodiment of the present invention. Here, the rotor side of the electric valve 1 is referred to as the upper side, and the needle valve side is referred to as the lower side. The term "orifice" refers to the gap between the needle valve and the valve seat when the valve is open, and the area of the annular surface formed by the outer diameter of the needle valve and the inner diameter of the valve seat at the position where the gap is smallest is the "orifice cross-sectional area". The term "orifice portion" refers to the flow path from the valve seat to the boundary with the flow straightening hole, which is a downstream portion. Furthermore, the term "flow path cross-sectional area" refers to the cross-sectional area of the flow path perpendicular to the direction in which the refrigerant flows.

(Configuration of Flow Control Valve)
The motor-operated valve 1 comprises a cylindrical valve body 10 with a bottom and an open top, a cylindrical can 45 with a top whose bottom end is hermetically joined by welding or the like to the top surface of the valve body 10, a guide stem 15 fixed to the inside of the valve body 10, a valve shaft 21 disposed inside the guide stem 15, and a rotor 30 connected and fixed to the valve shaft 21 so as to be integrally rotatable. A stator is disposed around the rotor 30 and fitted onto the outer periphery of the can 45 to rotate the rotor 30, but is not shown here. The rotor 30 and the stator form a stepping motor. The axis of the motor-operated valve 1 and the orifice portion is designated as L.

The valve body 10 is formed by connecting a hollow cylindrical portion 10a and a bottom wall portion 10b. The valve body 10 can be formed by pressing a SUS plate material, but it may also be formed by pressing a SUS material. However, the valve body 10 can be made of a material other than SUS (stainless steel) (e.g. brass), and can also be formed using a processing method other than pressing or pressing (e.g. cutting).

A circular opening 10d is formed in the center of the bottom wall portion 10b, and the valve seat member 11 is fixed to the opening 10d by brazing or the like.

Figure 2 is a vertical cross-sectional view of the valve seat member 11, Figure 3 is a perspective view of the valve seat member 11 from below, and Figure 4 is a bottom view of the valve seat member 11. Note that the cross-sectional view may differ from the cross-sectional configuration that is actually observed.

The approximately cylindrical valve seat member 11 is made up of an upper cylindrical portion 11a, a middle cylindrical portion 11b with a larger diameter than the upper cylindrical portion 11a, a lower cylindrical portion 11c with a larger diameter than the middle cylindrical portion 11b, a partition wall portion 11d extending radially inward from near the boundary between the middle cylindrical portion 11b and the lower cylindrical portion 11c, and an inner cylindrical portion 11e extending downward from the partition wall portion 11d. The lower end of the inner cylindrical portion 11e is provided with a truncated cone portion 11f.

The middle cylindrical portion 11b fits into the opening 10d of the valve body 10, the upper cylindrical portion 11a protrudes into the inside of the valve body 10, and the lower cylindrical portion 11c is disposed outside the valve body 10. An annular space SP is formed between the lower cylindrical portion 11c and the inner cylindrical portion 11e. A step portion 11g is formed on the inner peripheral side of the lower end of the lower cylindrical portion 11c. The end portion of the first pipe T1 (Figure 1) that has entered the annular space SP is inserted into the outer periphery of the inner cylindrical portion 11e and connected by brazing or the like. The step portion 11g becomes a portion for storing brazing material when the pipe T1 is brazed. In this specification, the first pipe T1 may be simply referred to as a pipe.

A cylindrical hole 11i is formed coaxially with the axis L, extending downward from the upper end of the inner cylindrical portion 11e along the axis L to the bottom wall 11h. A plurality of flow straightening holes 11j1, 11j2, 11j3, 11j4 (see FIG. 4) are formed at equal intervals, branching out in the circumferential direction, and extending diagonally outward from the outer periphery of the lower end of the cylindrical hole 11i, and the outer end of each flow straightening hole is located on the outer periphery of the truncated cone portion 11f. The number of flow straightening holes may be two, three, or five or more. The same applies to the embodiments described below other than the embodiment having a single flow straightening hole.

The cylindrical straightening holes 11j1, 11j2, 11j3, and 11j4 are inclined downward, and here, face the inner wall of the first pipe T1 assembled to the valve seat member 11. When the axis L is projected along the normal direction onto a plane that is parallel to the axis L and includes the central axes X1, X2, X3, and X4 of the straightening holes 11j1, 11j2, 11j3, and 11j4, the projected axis L intersects with the central axes X1, X2, X3, and X4 at an angle other than a right angle. The projected axis L toward the orifice side and the central axes X1, X2, X3, and X4 toward the tip side of the straightening holes form an obtuse angle on either side of the intersection.

Furthermore, the central axes X1, X2, X3, and X4 (FIG. 4) of the straightening holes 11j1, 11j2, 11j3, and 11j4 intersect the cylindrical hole 11i, but are in a twisted relationship with respect to the axis L, i.e., do not intersect spatially with the axis L. In other words, the central axes X1, X2, X3, and X4 pass between the inner circumferential surface of the cylindrical hole 11i and the axis L. Here, the minimum distances Δ between the central axes X1, X2, X3, and X4 and the axis L are equal to each other, but may be different. The minimum distance Δ is preferably in the range of 0.3φ to 0.7φ, where φ is the inner diameter of the straightening hole. In other words, the minimum distance Δ between the central axes X1, X2, X3, and X4 of the straightening holes and the axis L of the orifice portion is preferably 0.3 to 0.7 times the inner diameter of the straightening hole. If the minimum distance Δ is too small, the effect of generating swirling flow is small, and if the minimum distance Δ is too large, the motor-operated valve will become larger.

The number of flow straightening holes may be two, three, five or more, but it is preferable that they are arranged at equal intervals in the circumferential direction. The cylindrical hole 11i forms the orifice portion. A valve seat 11k is formed on the inner circumference of the upper end of the cylindrical hole 11i. The lengths and inner diameters of the flow straightening holes 11j1, 11j2, 11j3, and 11j4 are equal to each other, and these flow straightening holes have the same relationship in rotational symmetry with respect to the axis L. Therefore, the structure of the flow straightening hole 11j1 will be explained as a representative of the four flow straightening holes.

In this embodiment, the length of the flow straightening hole 11j1 is longer than the inner diameter of the flow straightening hole 11j1 and longer than the inner radius of the cylindrical hole 11i. The length of the flow straightening hole 11j1 refers to the distance between two points PT1 and PT2 when the inner wall of the flow straightening hole 11j1 is represented as a pair of line segments sandwiching the central axis X1 in a cross section of the motor-operated valve 1 cut by a plane parallel to the axis L and passing through the central axis X1, and the central axis X of the flow straightening hole 11j intersects with a straight line connecting one end of the line segments of the inner wall and a straight line connecting the other end of the line segments at points PT1 and PT2.

Furthermore, the total flow path cross-sectional area of the four straightening holes 11j1, 11j2, 11j3, and 11j4 is larger than the flow path cross-sectional area (i.e., the orifice cross-sectional area) formed between the conical portion 25d and the valve seat 11k at the maximum lift (maximum opening) of the needle valve (valve body) 25. Also, the flow path cross-sectional area of the cylindrical hole 11i is equal to or larger than the orifice cross-sectional area at the maximum opening. It is preferable that the total flow path cross-sectional area of the straightening holes 11j1, 11j2, 11j3, and 11j4 is larger than the flow path cross-sectional area of the cylindrical hole 11i.

In FIG. 1, an inlet opening 10e is formed in the hollow cylindrical portion 10a of the valve body 10, and the end of the second pipe T2 is inserted into the inlet opening 10e and connected by brazing or the like. The axis of the inlet opening 10e is O.

With the lower end of the can 45 butted against the upper end of the valve body 10, the flange-shaped disk 18 fits around the inner circumference of the lower end of the can 45, and they are joined by welding. This allows the valve body 10 and the can 45 to be integrated in a sealed state.

The flange-shaped disk 18 has multiple through holes (not shown), through which the refrigerant can move between the valve body 10 side and the can 45 side.

The resin guide stem 15 arranged inside the rotor 30 is made up of a solid cylindrical body 15a and a hollow cylindrical portion 15b connected together. The body 15a has a female threaded hole 15c along the axis L. A movable stopper 35 for the valve closing direction is also installed above the guide stem 15.

A flange-shaped disk 18 welded to the upper end of the valve body 10 is disposed on the outer periphery of the middle part of the hollow cylindrical portion 15b, and the guide stem 15 is fixed to the valve body 10 via this flange-shaped disk 18. A pressure equalizing hole 15d is formed in the hollow cylindrical portion 15b.

In order to set the control origin position of the rotor 30 and the valve shaft 21, a fixed stopper 55 for the closing direction with a rectangular cross section is provided on the upper surface of the main body 15a of the guide stem 15, protruding upward, and a fixed stopper 56 for the opening direction with a rectangular cross section is provided on the lower surface of the main body 15a of the guide stem 15, protruding downward. Here, the control origin position of the rotor 30 and the valve shaft 21 refers to the position when the movable stopper 35 for the closing direction is abutted against and locked against the fixed stopper 55 for the closing direction, and the rotor 30 and the valve shaft 21 reach their lowest positions.

The metallic valve shaft 21 is made up of an end 21a fitted with an annular connector 32 attached to the rotor 30, a male threaded portion 21b that screws into the female threaded hole 15c, a flange-shaped portion 21c formed near the lower end, and a lower end connecting portion 21d, all connected coaxially.

The valve closing direction movable stopper 35, which is fixed to the valve shaft 21, is disposed near the upper end of the male threaded portion 21b and is engaged with the lower surface of the upper wall of the rotor 30. A stopper portion 35a with a rectangular cross section is formed on the lower surface of the valve closing direction movable stopper 35.

A valve-opening direction movable stopper 36 is press-fitted near the lower end of the male threaded portion 21b of the valve shaft 21 so as to abut against the upper surface of the flange-shaped portion 21c. A stopper portion 36a with a rectangular cross section is formed on the upper surface of the valve-opening direction movable stopper 36. Here, a female thread is formed on the inner circumference of the valve-opening direction movable stopper 36, and the valve-opening direction movable stopper 36 is fixed to the valve shaft 21 by screwing it into the male threaded portion 21b.

Below the valve shaft 21, the valve holder 23 is slidably fitted inside the hollow cylindrical portion 15b. The valve holder 23 has a topped cylindrical shape with a hollow cylindrical portion 23a and an upper wall 23b connected to each other. A stepped opening 23c is formed in the center of the upper wall 23b, and the hollow cylindrical portion 23a has a communication hole 23d. In the closed valve state, the open lower end of the hollow cylindrical portion 23a of the valve holder 23 is disposed below the second pipe T2 and is closed by an annular member 27 fixed by crimping.

With the flange 21c of the valve shaft 21 abutting against the step of the stepped opening 23c, the lower end connecting portion 21d passes through the stepped opening 23c, and the valve shaft 21 and the valve holder 23 are fixedly connected by crimping the lower end connecting portion 21d to expand its diameter. A valve chamber 29 is defined between the valve body 10 and the valve holder 23.

The needle valve 25 is arranged so as to protrude from the valve holder 23 through the annular member 27. The needle valve 25 is composed of a cylindrical shaft portion 25a, a valve flange portion 25b, a valve cylinder portion 25c, a conical portion 25d that tapers downward, and a tapered portion 25e that is formed in multiple steps into a cone shape. The taper angle of the conical portion 25d (the angle at which it intersects with the axis L) is greater than the taper angle of the tapered portion 25e that is in contact with the conical portion 25d.

A ring-shaped member 31 is fitted onto the outer periphery of the shaft portion 25a by press fitting or the like. The outer diameter of the ring-shaped member 31 is larger than the inner diameter of the annular member 27, so that the needle valve 25 is prevented from falling off the valve holder 23. A washer 28 is disposed between the ring-shaped member 31 and the annular member 27 to reduce friction during relative rotation between the ring-shaped member 31 and the annular member 27.

A cylindrical spring receiving member 26 having a lower end flange 26a is disposed between the upper wall 23b of the valve holder 23 and the needle valve 25. Furthermore, a coil spring 24 is disposed between the upper wall 23b and the lower end flange 26a, and biases the spring receiving member 26 downward relative to the valve holder 23.

When the conical portion 25d is seated on the valve seat 11k of the valve seat member 11 and receives an upward reaction force, the spring bearing member 26, which is biased upward by the needle valve 25, comes into contact with the lower surface of the upper wall 23b of the valve holder 23 (or the lower end connecting portion 21d), and the needle valve 25 is axially locked to the valve shaft 21.

The valve shaft 21, valve holder 23, needle valve 25, and coil spring 24 described above move up and down while rotating substantially integrally with the guide stem 15 when the needle valve 25 is separated from the valve seat 11k (open valve state).

(Flow Control Valve Operation)
The operation of the motor-operated valve 1 will now be described in detail.
Here, it is assumed that the refrigerant (fluid) enters the valve chamber 29 from the second pipe T2.

When a pulsed current is supplied from an external control device to a stator (not shown), the rotor 30 and valve shaft 21 are rotated in one direction, and the valve shaft 21 and the movable stopper 35 for the valve closing direction rotate and descend due to a screw feed mechanism consisting of the female threaded hole 15c and the male threaded portion 21b, and the needle valve 25 seats on the valve seat 11k and closes the orifice. This blocks the flow of refrigerant from the valve chamber 29 toward the first pipe T1.

At this point, the movable stopper 35 has not yet come into contact with the fixed stopper 55, and the downward rotation of the rotor 30 and valve shaft 21 is not stopped, and pulse power supply continues until the coil spring 24 is compressed by a predetermined amount. As a result, the needle valve 25 is restrained from rotating while remaining seated on the valve seat 11k, while the rotor 30, valve shaft 21, valve holder 23, etc. continue to rotate and descend.

At this time, the valve shaft 21 and valve holder 23 descend relative to the seated needle valve 25, causing the coil spring 24 to contract and be compressed, thereby absorbing the downward force of the valve shaft 21 and valve holder 23. After that, when the amount of compression of the coil spring 24 reaches a predetermined amount, the movable stopper 35 abuts and engages the fixed stopper 55, the rotor 30 and valve shaft 21 reach their lowest positions, and the descent of the rotor 30 and valve shaft 21 is forcibly stopped even if pulse power supply to the stator continues.

In this way, even after the needle valve 25 seats on the valve seat 11k and the orifice is closed, the rotor 30, valve shaft 21, and valve holder 23 continue to rotate downward until the movable stopper 35 reaches the control origin position where it abuts and engages with the fixed stopper 55, compressing the coil spring 24. Therefore, the needle valve 25 is strongly pressed against the valve seat 11k by the biasing force of the coil spring 24, reliably preventing refrigerant leakage, etc.

On the other hand, when a pulse current of reverse polarity is supplied from the control origin position to the stator, the rotor 30 and the valve shaft 21 are rotated in the opposite direction to when the valve is closed, and the rotor 30, the valve shaft 21, the valve holder 23, and the movable stopper 36 for the valve opening direction are rotated and raised by the screw feed mechanism consisting of the female screw hole 15c and the male screw portion 21b. As a result, the pressing force against the needle valve 25 is weakened, the coil spring 24 is expanded, and when the needle valve 25 leaves the valve seat 11k, the orifice is opened. As a result, the refrigerant that has entered the valve chamber 29 from the second pipe T2 passes through the gap between the conical portion 25d and the valve seat 11k, and flows through the cylindrical hole 11i to the first pipe T1.

In this case, the lift amount of the needle valve 25 is determined according to the pulse power supply to the stator, so the flow rate of the refrigerant can be controlled. By continuing the pulse power supply, the needle valve 25 will eventually be fully open. If the pulse power supply is continued, the movable stopper 36 will come into contact with and be locked by the fixed stopper 56 for the valve opening direction, thereby forcibly stopping the rotation and lifting of the rotor 30, valve shaft 21, and valve holder 23.

According to this embodiment, when the valve is opened, the refrigerant that passes through the gap between the conical portion 25d and the valve seat 11k and enters the cylindrical hole 11i of the valve seat member 11 comes into contact with the bottom wall 11h, where the direction of the flow is changed, and the refrigerant flows out of the valve seat member 11 through the cylindrical straightening holes 11j1, 11j2, 11j3, and 11j4. At this time, the central axes X1, X2, X3, and X4 of the straightening holes 11j1, 11j2, 11j3, and 11j4 are in a twisted relationship with the axis L, so that the refrigerant closer to the inner circumferential surface of the cylindrical hole 11i is supplied to each straightening hole more quickly than the refrigerant near the axis L in the cylindrical hole 11i.

In addition, the central axes X1, X2, X3, and X4 of the flow straightening holes 11j1, 11j2, 11j3, and 11j4 are offset toward the inner circumference of the cylindrical hole 11i with the same arrangement relative to the axis L, so that a swirling flow RF is generated in the refrigerant passing through the cylindrical hole 11i by being discharged from the flow straightening holes 11j1, 11j2, 11j3, and 11j4, as shown by the arrows in FIG. 2.

When the valve is open, the refrigerant passing through the orifice between the conical portion 25d and the valve seat 11k is often in a gas-liquid mixed state. When such a refrigerant passes through a narrow orifice, sound is generated due to the alternating passage of gas and liquid. However, if turbulence occurs in the cylindrical hole 11i, this may cause irregular changes in the sound, which the user may recognize as noise. In contrast, according to this embodiment, by creating a swirling flow RF in the cylindrical hole 11i, the generation of turbulence that generates many small vortexes is suppressed, and a stable state can be maintained inside the cylindrical hole 11i. Therefore, the sound when the refrigerant in the gas-liquid phase passes through the orifice can be equalized, thereby suppressing the user from recognizing it as noise.

In addition, when a swirling flow RF is created in the cylindrical hole 11i, the liquid phase refrigerant, which has a high specific gravity, tends to collect on the outside due to centrifugal force, and the gas phase refrigerant, which has a low specific gravity, tends to collect in the center, thereby maintaining the refrigerant in a more stable state.

Furthermore, compared to the case where turbulence occurs within the cylindrical hole 11i, the pressure applied to the needle valve 25 is stabilized by creating a swirling flow RF, and vibration of the needle valve 25 and abnormal noise caused by the vibration can be suppressed.

In addition, by providing a straightening effect to the valve seat member 11 with a straightening hole, there is no need to provide a separate straightening member, reducing the number of parts.

In addition, according to this embodiment, the refrigerant that has passed through the cylindrical hole 11i, which is the orifice portion, is forced to flow out from the flow straightening holes 11j1, 11j2, 11j3, and 11j4 so that it collides with the inner wall of the first pipe T1, forcibly reducing the flow rate of the refrigerant and restoring the refrigerant pressure before turbulence occurs. This makes it possible to suppress the generation of bubbles that cause noise.

Furthermore, the refrigerant flowing out from the straightening holes 11j1, 11j2, 11j3, and 11j4 is also a swirling flow, so it flows downstream while swirling along the inner wall of the first pipe T1. At this time, the liquid phase refrigerant, which has a high specific gravity, tends to collect on the inner wall side of the first pipe T1 due to centrifugal force, and the gas phase refrigerant, which has a low specific gravity, tends to collect on the center side of the first pipe T1, which allows the refrigerant to be maintained in a more stable state and reduces abnormal noise compared to when there is no swirling flow.

When the refrigerant flows from the first pipe T1 to the second pipe T2, the refrigerant that enters the valve seat member 11 from the first pipe T1 has its flow direction changed by the flow straightening holes 11j1, 11j2, 11j3, and 11j4, resulting in a swirling flow, and does not flow straight along the axial direction toward the orifice. Therefore, the refrigerant becomes stable when passing through the orifice, and the axial component of the flow velocity becomes small, which suppresses vibration of the needle valve 25 when the valve is opened.

Second Embodiment
Fig. 5 is a vertical cross-sectional view of a valve seat member 11A that can be used in the motor-operated valve according to the second embodiment. Fig. 6 is a bottom view of the valve seat member 11A according to the second embodiment. The configuration of the motor-operated valve other than the valve seat member 11A is the same as that of the first embodiment, so a duplicated description will be omitted. In addition, the configuration of the valve seat member 11A other than the straightening hole is the same as that of the valve seat member 11 according to the first embodiment, so the same reference numerals are used and a duplicated description will be omitted. In the following embodiments, a swirl flow of the refrigerant can be created in the downstream area of the orifice portion and the straightening hole as in the first embodiment.

The valve seat member 11A of this embodiment differs from the valve seat member 11 shown in FIG. 4 in that it has two straightening holes. More specifically, two straightening holes 11Aj1, 11Aj2 extending diagonally outward from the lower end outer periphery of the cylindrical hole 11i are formed in opposite directions by branching in the circumferential direction, and the outer end of each straightening hole is located on the outer periphery of the truncated cone portion 11f. The central axes X1, X2 of the straightening holes 11Aj1, 11Aj2 intersect the cylindrical hole 11i, but are in a twisted relationship with the axis L, i.e., do not intersect spatially with the axis L. This embodiment can also achieve the same effects as the first embodiment.

[Third embodiment]
Fig. 7 is a vertical cross-sectional view of a valve seat member 11B that can be used in the motor-operated valve according to the third embodiment. Fig. 8 is a bottom view of the valve seat member 11B according to the third embodiment. The configuration of the motor-operated valve other than the valve seat member 11B is the same as that of the first embodiment, so a duplicated description will be omitted. In addition, the configuration of the valve seat member 11B other than the flow straightening hole is the same as that of the valve seat member 11 according to the first embodiment, so the same reference numerals are used and a duplicated description will be omitted.

The valve seat member 11B of this embodiment differs from the valve seat member 11 shown in FIG. 4 in that it has three straightening holes. More specifically, the straightening holes 11Bj1, 11Bj2, and 11Bj3 that extend diagonally outward from the lower end outer periphery of the cylindrical hole 11i are branched in the circumferential direction and formed at equal intervals, and the outer end of each straightening hole is located on the outer periphery of the truncated cone portion 11f. The central axes X1, X2, and X3 of the straightening holes 11Bj1, 11Bj2, and 11Bj3 intersect the cylindrical hole 11i, but are in a twisted relationship with the axis L, that is, they do not spatially intersect the axis L. This embodiment can also achieve the same effects as the first embodiment.

[Fourth embodiment]
9 is a vertical cross-sectional view of a valve seat member 11C that can be used in a motor-operated valve according to a fourth embodiment. The configuration of the motor-operated valve other than the valve seat member 11C is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11C other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Cj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

The valve seat member 11C of this embodiment differs from the valve seat member 11 shown in FIG. 2 mainly in that a tapered portion 11Cm, which is the lower end of the cylindrical hole 11Ci, is formed in the bottom wall 11Ch. A flow straightening hole 11Cj1 is in contact with a part of the tapered portion 11Cm. In this embodiment as well, a truncated cone portion 11Cf is disposed at the lower end of the inner cylindrical portion 11Ce. The central axis X1 of the flow straightening hole 11Cj1 intersects the cylindrical hole 11Ci, but is in a twisted relationship with the axis L, i.e., does not intersect spatially with the axis L.

When the valve is open, the refrigerant that passes through the orifice flows along the cylindrical hole 11Ci, which is the orifice portion, and reaches the tapered portion 11Cm. At least a portion of the refrigerant remains in the tapered portion 11Cm before entering the flow straightening hole 11Cj1, which has the effect of making it easier to restore the refrigerant pressure. In addition, when the refrigerant passes through the edge portion of the tapered portion 11Cm, it also has the effect of dispersing air bubbles. The tapered portion 11Cm can be formed, for example, by transferring the shape of the tip of a cutting tool such as a drill when forming the cylindrical hole 11Ci.

[Fifth embodiment]
10 is a vertical cross-sectional view of a valve seat member 11D that can be used in a motor-operated valve according to a fifth embodiment. The configuration of the motor-operated valve other than the valve seat member 11D is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11D other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Dj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

The valve seat member 11D of this embodiment differs from the valve seat member 11 shown in FIG. 2 mainly in that a communication opening 11Dm is formed that penetrates the bottom wall 11Dh parallel to the axis L from the middle position of the flow straightening hole 11Dj1 and has an end located on the top surface (lower surface) of the truncated cone portion 11Df. The inner diameter of the communication opening 11Dm is preferably 1/4 or less of the inner diameter of the flow straightening hole 11Dj1. In this embodiment as well, the lower end of the inner cylindrical portion 11De is provided with a truncated cone portion 11Df. The central axis X1 of the flow straightening hole 11Dj1 intersects with the cylindrical hole 11Di, but is in a twisted relationship with the axis L, i.e., does not intersect with the axis L spatially.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Di, which is the orifice portion, and reaches the bottom wall 11Dh. From here, the refrigerant passes through the flow straightening hole 11Dj1 and flows out of the valve seat member 11D, but in doing so, it may collide with the inner wall of the first pipe T1 and form a vortex. Such a vortex may prevent the refrigerant from recovering its pressure.

In contrast, according to the present embodiment, when the refrigerant passes through the upper end of the communication opening 11Dm, negative pressure is generated inside the communication opening 11Dm, so that the refrigerant is sucked up from the lower end of the communication opening 11Dm. This allows the vortex that is formed when the refrigerant collides with the inner wall of the first pipe T1 to quickly disappear.

Sixth embodiment
11 is a longitudinal sectional view of a valve seat member 11E that can be used in a motor-operated valve according to a sixth embodiment. The configuration of the motor-operated valve other than the valve seat member 11E is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11E other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Ej1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

The inner cylindrical portion 11Ee extending downward from the partition wall portion 11d consists of an expanded diameter portion 11Ee1 on the partition wall portion 11d side and a reduced diameter portion 11Ee2 on the tip side, which has a smaller outer diameter than the expanded diameter portion 11Ee1. The first pipe T1 (Figure 1) fits only into the expanded diameter portion 11Ee1.

The flow straightening hole 11Ej1 is formed to extend obliquely from the lower end of the cylindrical hole 11Ei formed inside the inner cylindrical portion 11Ee toward the valve seat 11k. The flow straightening hole 11Ej1 faces the inner wall of the first pipe T1 assembled to the valve seat member 11E. In other words, the central axis X1 of the flow straightening hole 11Ej1 intersects with the inner wall of the first pipe T1 (see FIG. 1) but does not intersect with the axis L.

When the axis L is projected along the normal direction onto a plane that is parallel to the axis L and includes the central axis X1 of the flow straightening hole 11Ej1, the projected axis L and the central axis X1 intersect at an angle other than a right angle. The projected axis L toward the orifice and the central axis X1 toward the tip of the flow straightening hole form an acute angle on either side of the intersection.

In this embodiment, the length of the flow straightening hole 11Ej1 (the shortest axial length of the hole inner wall) is longer than the inner diameter of the flow straightening hole 11Ej1 and longer than the inner circumferential radius of the cylindrical hole 11Ei. The total flow path cross-sectional area of the four flow straightening holes is larger than the orifice cross-sectional area when the valve is fully open. The flow path cross-sectional area of the cylindrical hole 11Ei is equal to or larger than the orifice cross-sectional area when the valve is fully open. It is preferable that the total flow path cross-sectional area of the flow straightening holes is larger than the flow path cross-sectional area of the cylindrical hole 11Ei.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Ei, which is the orifice portion, and reaches the bottom wall 11Eh. Here, the refrigerant's flow direction is bent at an acute angle, passes through the flow straightening hole 11Ej1, and flows out of the valve seat member 11E.

Because there is a gap between the first pipe T1 and the reduced diameter portion 11Ee2, the refrigerant flowing out of the reduced diameter portion 11Ee2 hits the inner wall of the first pipe T1 and then passes through the gap between the first pipe T1 and the reduced diameter portion 11Ee2 and flows downward. At this time, the flow speed of the refrigerant flowing out from between the first pipe T1 and the reduced diameter portion 11Ee2 is slower than the flow speed of the refrigerant passing through the orifice cross-sectional area when the valve is fully open.

[Seventh embodiment]
Fig. 12 is a vertical cross-sectional view of a valve seat member 11F that can be used in a motor-operated valve according to the seventh embodiment. Fig. 13 is a bottom view of the valve seat member 11F according to the seventh embodiment. The configuration of the motor-operated valve other than the valve seat member 11F is the same as that of the first embodiment, so a duplicated description will be omitted. In addition, the configuration of the valve seat member 11F other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, so the same reference numerals are used and a duplicated description will be omitted.

The valve seat member 11F of this embodiment differs primarily in the shape of the inner cylindrical portion 11Fe and the flow straightening hole 11Fj.

The inner cylindrical portion 11Fe extending downward from the partition wall portion 11d is made up of an expanded diameter portion 11Fe1 on the partition wall portion 11d side and a reduced diameter portion 11Fe2 on the tip side, which has a smaller outer diameter than the expanded diameter portion 11Fe1. The first pipe T1 (Figure 1) fits only into the expanded diameter portion 11Fe1.

The flow straightening hole 11Fj is formed to extend radially outward from the lower end of the cylindrical hole 11Fi formed inside the inner cylindrical portion 11Fe. The central axis X1 of the flow straightening hole 11Fj intersects with the cylindrical hole 11Fi, but is in a twisted relationship with the axis L, i.e., does not intersect spatially with the axis L. When the axis L is projected along the normal direction onto a plane that is parallel to the axis L and includes the central axis X1 of the flow straightening hole 11Fj, the projected axis L and the central axis X1 are perpendicular to each other. The flow straightening hole 11Fj faces the inner wall of the first piping T1 assembled to the valve seat member 11F.

In this embodiment, too, it is preferable that the length of the flow straightening hole 11Fj is longer than the inner diameter of the flow straightening hole 11Fj and longer than the inner radius of the cylindrical hole 11Fi. The flow path cross-sectional area of the flow straightening hole 11Fj is larger than the orifice cross-sectional area when the valve is fully open. The minimum flow path cross-sectional area of the cylindrical hole 11Fi is equal to or larger than the orifice cross-sectional area when the valve is fully open. It is preferable that the flow path cross-sectional area of the flow straightening hole 11Fj is larger than the flow path cross-sectional area of the cylindrical hole 11Fi.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Fi, which is the orifice portion, and reaches the bottom wall 11Fh. Here, the refrigerant's flow direction is bent at a right angle, passes through the flow straightening hole 11Fj, and flows out of the valve seat member 11F.

Because there is a gap between the first pipe T1 and the reduced diameter portion 11Fe2, the refrigerant flowing out of the reduced diameter portion 11Fe2 hits the inner wall of the first pipe T1 and then passes through the gap between the first pipe T1 and the reduced diameter portion 11Fe2 and flows downward. At this time, the flow speed of the refrigerant flowing out from between the first pipe T1 and the reduced diameter portion 11Fe2 is slower than the flow speed of the refrigerant passing through the orifice cross-sectional area when the valve is fully open.

Eighth embodiment
Fig. 14 is a vertical cross-sectional view of a valve seat member 11G that can be used in a motor-operated valve according to an eighth embodiment. Fig. 15 is a bottom view of the valve seat member 11G according to the eighth embodiment. The configuration of the motor-operated valve other than the valve seat member 11G is the same as that of the first embodiment, so a duplicated description will be omitted. In addition, the configuration of the valve seat member 11G other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, so the same reference numerals are used and a duplicated description will be omitted.

The valve seat member 11G of this embodiment differs from the valve seat member 11F shown in Figures 12 and 13 mainly in that a tapered portion 11Gm is formed at the inner end of the flow straightening hole 11Gj.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Gi, which is the orifice portion, and reaches the tapered portion 11Gm. At least a portion of the refrigerant remains in the tapered portion 11Gm before entering the straightening hole 11Gj, which has the effect of making it easier to restore the refrigerant pressure. In addition, when the refrigerant passes through the edge of the tapered portion 11Gm, it also has the effect of dispersing air bubbles. The tapered portion 11Gm can be formed, for example, by transferring the shape of the tip of a cutting tool such as a drill when forming the straightening hole 11Gj.

[Ninth embodiment]
16 is a vertical cross-sectional view of a valve seat member 11H that can be used in a motor-operated valve according to a ninth embodiment. The configuration of the motor-operated valve other than the valve seat member 11H is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11H other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Hj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

The cylindrical hole 11Hi has a first hole 11Hi1 arranged below the valve seat 11k, a second hole 11Hi2 larger in diameter than the first hole 11Hi1, and a third hole 11Hi3 larger in diameter than the second hole 11Hi2. The first hole 11Hi1 and the second hole 11Hi2 are connected by a first tapered portion 11Hi4, and the second hole 11Hi2 and the third hole 11Hi3 are connected by a second tapered portion 11Hi5. The flow straightening hole 11Hj1 is connected to the lower end of the third hole 11Hi3 (and the second tapered portion 11Hi5). The cylindrical hole 11Hi can be machined using, for example, an end mill tool whose shank diameter is smaller than the outer diameter of the cutting edge. The flow passage cross-sectional area of the first hole 11Hi1 is equal to or larger than the orifice cross-sectional area when the valve is fully open. The total cross-sectional area of the flow straightening holes is preferably larger than the cross-sectional area of the flow straightening holes 11Hi1. The central axis X1 of the flow straightening holes 11Hj1 intersects with the cylindrical hole 11Hi, but is in a twisted relationship with the axis L, i.e., does not spatially intersect with the axis L.

When the valve is open, the refrigerant that passes through the orifice flows in a swirling motion along the first hole 11Hi1, the first tapered portion 11Hi4, the second hole 11Hi2, the second tapered portion 11Hi5, and the third hole 11Hi3, and reaches the bottom wall 11Hh. At this time, the flow path cross-sectional area expands in three stages from the orifice to the bottom wall 11Hh. This allows the refrigerant pressure to be gradually restored.

Furthermore, the refrigerant flows out of the valve seat member 11H through the straightening hole 11Hj1 facing diagonally downward and hits the inner wall of the first pipe T1, forcibly reducing the flow rate of the refrigerant and allowing the refrigerant pressure to be restored before turbulence occurs.

The total cross-sectional area of the four straightening holes (11Hj1) is preferably larger than the cross-sectional area of the first hole 11Hi1. Furthermore, it is more preferable that the total cross-sectional area of the four straightening holes (11Hj1) is smaller than the cross-sectional area of the third hole 11Hi3.

[Tenth embodiment]
17 is a vertical cross-sectional view of a valve seat member 11I that can be used in a motor-operated valve according to a tenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11I is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11I other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Ij1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

In this embodiment, the central axis X1 of the flow straightening hole 11Ij1 also intersects with the inner wall of the first pipe T1 (see FIG. 1), but does not intersect with the axis L.

The cylindrical hole 11Ii has a first hole 11Ii1 arranged below the valve seat 11k and a second hole 11Ii2 with a larger diameter than the first hole 11Ii1. The first hole 11Ii1 and the second hole 11Ii2 are connected by a tapered portion 11Ii3. The lower end of the second hole 11Ii2 is connected to the flow straightening hole 11Ij1. The cylindrical hole 11Ii can be machined using, for example, an end mill tool with a shank diameter smaller than the outer diameter of the cutting edge. The flow passage cross-sectional area of the first hole 11Ii1 is equal to or larger than the orifice cross-sectional area when the valve is fully open. It is preferable that the total flow passage cross-sectional area of the flow straightening holes is greater than the flow passage cross-sectional area of the first hole 11Ii1.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the first hole 11Ii1, the tapered portion 11Ii3, and the second hole 11Ii2, and reaches the bottom wall 11Ih. At this time, the flow path cross-sectional area expands in two stages from the orifice to the bottom wall 11Ih. This allows the refrigerant pressure to gradually recover.

Furthermore, the refrigerant flows out of the valve seat member 11I through the straightening hole 11Ij1 facing diagonally downward and hits the inner wall of the first pipe T1, forcibly reducing the flow rate of the refrigerant and allowing the refrigerant pressure to be restored before turbulence occurs.

[Eleventh embodiment]
18 is a vertical cross-sectional view of a valve seat member 11J that can be used in a motor-operated valve according to an eleventh embodiment. The configuration of the motor-operated valve other than the valve seat member 11J is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11J other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Jj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

The cylindrical hole 11Ji has a first hole 11Ji1 arranged below the valve seat 11k and a second hole 11Ji2 having a larger diameter than the first hole 11Ji1. The first hole 11Ji1 and the second hole 11Ji2 are connected by a tapered portion 11Ji3. The lower end of the second hole 11Ji2 is connected to the flow straightening hole 11Jj1. The cylindrical hole 11Ji can be machined using, for example, an end mill tool whose shank diameter is smaller than the outer diameter of the cutting edge. The flow cross-sectional area of the first hole 11Ji1 is equal to or larger than the orifice cross-sectional area when the valve is fully open. It is preferable that the total flow cross-sectional area of the flow straightening holes is larger than the flow cross-sectional area of the first hole 11Ji1. The central axis X1 of the flow straightening hole 11Jj1 intersects the cylindrical hole 11Ji, but is in a twisted relationship with respect to the axis L, i.e., does not intersect spatially with the axis L.

The central hole 11Jn, which is connected to the lower end of the cylindrical hole 11Ji, is coaxial with the cylindrical hole 11Ji and has an inner diameter smaller than the inner diameters of the cylindrical hole 11Ji and the flow straightening hole 11Jj1.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the first hole 11Ji1, the tapered portion 11Ji3, and the second hole 11Ji2, and reaches the bottom wall 11Jh. At this time, the flow path cross-sectional area expands in two stages from the orifice to the bottom wall 11Jh. This allows the refrigerant pressure to gradually recover.

Some of the refrigerant that reaches the bottom wall 11Jh passes through the straightening holes 11Jj1 and flows out of the valve seat member 11J, where it collides with the first pipe T1, which may cause a vortex to form. On the other hand, the rest of the refrigerant that reaches the bottom wall 11Jh passes straight through the central hole 11Jn and flows out of the valve seat member 11J, which has the effect of eliminating the vortex that has formed on the inner wall of the first pipe T1. This allows for a quick recovery of the refrigerant pressure.

[Twelfth embodiment]
19 is a vertical cross-sectional view of a valve seat member 11K that can be used in a motor-operated valve according to a twelfth embodiment. The configuration of the motor-operated valve other than the valve seat member 11K is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11K other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Kj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

In this embodiment, the central axis X1 of the flow straightening hole 11Kj1 also intersects with the inner wall of the first pipe T1 (see FIG. 1), but does not intersect with the axis L.

In this embodiment, the flow straightening hole 11Kj1 is connected between the lower end and the upper end of the cylindrical hole 11Ki. As a result, a refrigerant retention portion 11Kp is formed in the bottom wall 11Kh at the lower end of the cylindrical hole 11Ki up to the connection with the flow straightening hole 11Kj1.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Ki, which is the orifice portion, and reaches the retention portion 11Kp in the bottom wall 11Kh. Here, the flow of the refrigerant makes a U-turn and passes through the straightening hole 11Kj1 to flow out of the valve seat member 11K, at which point the pressure of the refrigerant is restored and the number of air bubbles can be reduced.

[Thirteenth embodiment]
20 is a vertical cross-sectional view of a valve seat member 11L that can be used in a motor-operated valve according to a thirteenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11L is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11L other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment as well, four straightening holes (two in the figure) are provided.

The valve seat member 11L of this embodiment differs from the twelfth embodiment in that the connection position of the flow straightening hole 11Lj3, which faces the flow straightening hole 11Lj1, to the cylindrical hole 11Li is shifted (displaced) by a distance σ downward in the axial direction. The distance σ is preferably 0.2φ to 0.8φ, where φ is the inner diameter of the flow straightening hole. This makes it possible to reduce the flow speed of the refrigerant passing through the cylindrical hole 11Li while swirling. Note that for each flow straightening hole, the connection positions of the adjacent flow straightening holes to the cylindrical hole 11Li may be shifted by an equal distance in the axial direction, or two sets of flow straightening holes may be shifted in the axial direction at a time.

[Fourteenth embodiment]
21 is a vertical cross-sectional view of a valve seat member 11M that can be used in a motor-operated valve according to a fourteenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11M is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11M other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Mj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

In this embodiment, the central axis X1 of the flow straightening hole 11Mj1 also intersects with the inner wall of the first pipe T1 (see FIG. 1), but does not intersect with the axis L.

The inner cylindrical portion 11Me extending downward from the partition wall portion 11d consists of an enlarged diameter portion 11Me1 on the partition wall portion 11d side and a reduced diameter portion 11Me2 on the tip side, which has a smaller outer diameter than the enlarged diameter portion 11Me1. A truncated cone portion 11Mf is formed at the lower end of the reduced diameter portion 11Me2. The first pipe T1 (Figure 1) fits only into the enlarged diameter portion 11Me1.

The flow straightening hole 11Mj1 is formed so as to extend obliquely downward from the lower end of the cylindrical hole 11Mi formed inside the inner cylindrical portion 11Me. In addition, a communication opening 11Mn is formed so as to extend obliquely from the middle position of the flow straightening hole 11Mj1 toward the partition portion 11d. The inner diameter of the communication opening 11Mn is preferably 1/4 or less of the inner diameter of the flow straightening hole Mj1.

When the valve is open, the refrigerant that passes through the orifice flows while swirling along the cylindrical hole 11Mi, which is the orifice portion, and reaches the bottom wall 11Mh. From here, the refrigerant passes through the flow straightening hole 11Mj1 and flows out of the valve seat member 11M, but in doing so, it may collide with the inner wall of the first pipe T1 and form a vortex. Such a vortex may prevent the refrigerant from recovering its pressure.

In contrast, according to the present embodiment, when the refrigerant passes through the lower end of the communication opening 11Mn, negative pressure is generated inside the communication opening 11Mn, so the refrigerant is sucked in from the upper end of the communication opening 11Mn. This allows the vortex that is formed when the refrigerant collides with the inner wall of the first pipe T1 to quickly disappear.

[Fifteenth embodiment]
22 is a longitudinal sectional view of a valve seat member 11N that can be used in a motor-operated valve according to a fifteenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11N is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11N other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configurations of the flow straightening holes 11Nj1, 11Nj2, and 11Nj3 will be described as representatives of the twelve flow straightening holes, but the other flow straightening holes have the same configuration.

In this embodiment, the inner cylindrical portion 11Ne is longer than in the first embodiment. The inner cylindrical portion 11Ne consists of an expanded diameter portion 11Ne1 on the partition wall portion 11d side and a reduced diameter portion 11Ne2 on the tip side, which has a smaller outer diameter than the expanded diameter portion 11Ne1. The first pipe T1 (FIG. 1) fits only into the expanded diameter portion 11Ne1. In the inner cylindrical portion 11Ne, the flow straightening holes 11Nj1, 11Nj2, and 11Nj3 are arranged in a row in a position where they overlap vertically in the direction along the axis L. The other flow straightening holes are also similarly arranged in three rows of three. The central axes X1, X2, and X3 of the flow straightening holes 11Nj1, 11Nj2, and 11Nj3 pass through the same plane parallel to the axis L and intersect the inner wall of the first pipe T1 (see FIG. 1), but do not intersect the axis L.

In this embodiment, the lowest straightening hole 11Nj3 is connected to the cylindrical hole 11Ni above the lower end of the cylindrical hole 11Ni, but it may also be connected to the lower end of the cylindrical hole 11Ni.

According to this embodiment, by providing four sets of flow straightening holes arranged in three rows, a stronger swirling flow can be created inside the cylindrical hole 11Ni. Note that the flow straightening holes can be provided in any number of rows and any number of sets.

[Sixteenth embodiment]
23 is a longitudinal sectional view of a valve seat member 11O that can be used in a motor-operated valve according to a sixteenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11O is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11O other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore a duplicated description will be omitted by assigning the same reference numerals. In this embodiment, the configurations of the flow straightening holes 11Oj1, 11Oj2, 11Oj3 and the flow straightening holes 11Oj4, 11Oj5, 11Oj6 will be described as representatives of the twelve flow straightening holes, but the other flow straightening holes have the same configuration.

The valve seat member 11O of this embodiment differs from the fifteenth embodiment in that the connection position of the flow straightening hole 11Oj4 facing the flow straightening hole 11Oj1 to the cylindrical hole 11Oi is shifted downward by a distance σ in the axial direction, the connection position of the flow straightening hole 11Oj5 facing the flow straightening hole 11Oj2 to the cylindrical hole 11Oi is shifted downward by a distance σ in the axial direction, and the connection position of the flow straightening hole 11Oj6 facing the flow straightening hole 11Oj3 to the cylindrical hole 11Oi is shifted downward by a distance σ in the axial direction. This makes it possible to reduce the flow velocity of the refrigerant passing through the cylindrical hole 11Oi while swirling. Note that the connection positions of the adjacent flow straightening holes to the cylindrical hole 11Oi for each flow straightening hole may be shifted by the same amount in the axial direction.

[Seventeenth embodiment]
24 is a vertical cross-sectional view of a valve seat member 11P that can be used in a motor-operated valve according to a seventeenth embodiment. The configuration of the motor-operated valve other than the valve seat member 11P is the same as that of the first embodiment, and therefore a duplicated description will be omitted. In addition, the configuration of the valve seat member 11P other than the inner cylindrical portion is the same as that of the valve seat member 11 according to the first embodiment, and therefore the same reference numerals are used and a duplicated description will be omitted. In this embodiment, the configuration of the flow straightening hole 11Pj1 will be described as a representative of the four flow straightening holes, but the other flow straightening holes have the same configuration.

In this embodiment, the cylindrical hole 11Pi has an upper cylindrical hole 11Pi1 that is connected to the orifice, and a lower cylindrical hole 11Pi2 that is smaller in diameter than the upper cylindrical hole 11Pi1. A spiral groove 11Pp is formed on at least a portion of the inner circumference of the lower cylindrical hole 11Pi2 as a swirling flow generating structure.

The spiral direction of the spiral groove 11Pp is determined according to the positional relationship between the axis L and the straightening hole 11Pj1. More specifically, when the axis L and the straightening hole 11Pj1 are in the positional relationship shown in FIG. 4, the refrigerant flowing along the cylindrical hole 11Pi swirls counterclockwise along the direction of travel. In this case, it is preferable that the spiral groove 11Pp has a left-handed spiral direction toward the bottom end of the cylindrical hole 11Pi to strengthen the swirling flow of the refrigerant. It is also possible to fit a cylinder with a spiral groove formed on its inner circumference into the cylindrical hole 11Pi.

[Modification]
25 is a diagram showing a configuration in which a valve seat member 11 and a porous filter FT that can be used in a motor-operated valve according to a modification of this embodiment are combined, with the left half being a vertical cross-sectional view and the right half being a side view. Since the configuration other than the porous filter FT is the same as that of the first embodiment, repeated explanations will be omitted.

A metal or resin porous filter FT is disposed around the inner cylindrical portion 11e of the valve seat member 11, covering the area from the position indicated by the dotted line to below the truncated cone portion 11f. The porous filter FT is formed into a cylindrical shape from, for example, foam metal, mesh material, or punched metal, and is wrapped around the outer circumference of the inner cylindrical portion 11e, covering the outer ends of the flow straightening holes 11j1, etc.

The refrigerant flowing out from the flow straightening holes 11j1 etc. passes through the porous filter FT, which breaks down the bubbles, further reducing noise. The valve seat member combined with the porous filter FT is not limited to the first embodiment, and may be combined with other embodiments.

1 Motor-operated valve 10 Valve body 11 to 11O Valve seat member 11k Valve seat 15 Guide stem 21 Valve shaft 23 Valve holder 24 Coil spring 25 Needle valve 26 Spring receiving member 27 Annular member 29 Valve chamber 30 Rotor 35 Movable stopper for closing direction 36 Movable stopper for opening direction 55 Fixed stopper for closing direction 56 Fixed stopper for opening direction FT Porous filter

Claims (12)

A valve body having a valve chamber;
a valve seat member provided on the valve body and having a valve seat;
a valve body disposed in the valve chamber and movable up and down in a direction toward or away from the valve seat,
the valve seat member includes an orifice portion adjacent to the valve seat and a flow straightening hole communicating with the orifice portion,
The valve seat member has a truncated cone portion, and an outlet of the flow straightening hole is formed on an outer circumferential surface of the truncated cone portion,
a central axis of the flow straightening hole is not parallel to and does not intersect with the axis of the orifice portion, and passes between an inner circumferential surface of the orifice portion and the axis of the orifice portion,
when the axis of the orifice portion is projected along a normal direction of a plane including the central axis of the flow straightening hole and parallel to the axis of the orifice portion, the central axis of the flow straightening hole intersects with the projected axis of the orifice portion, and an obtuse angle is formed between the projected axis toward the valve seat side and the central axis toward the tip side of the flow straightening hole, with the intersection therebetween.
A motor-operated valve. The minimum distance between the central axis of the flow straightening hole and the axis of the orifice portion is 0.3 to 0.7 times the inner diameter of the flow straightening hole.
2. The motor-operated valve according to claim 1. The flow straightening hole is branched into a plurality of holes from the orifice portion.
3. The motor-operated valve according to claim 1 or 2. The valve seat member has the orifice portion formed therein and includes a cylindrical portion that fits into a pipe.
The motor-operated valve according to any one of claims 1 to 3. a truncated cone portion is formed at an end of the cylindrical portion, and an outer end of the flow straightening hole is located on an outer circumferential surface of the truncated cone portion;
5. The motor-operated valve according to claim 4. A tapered portion is formed at an inner end of the orifice portion.
The motor-operated valve according to any one of claims 1 to 5. a communication opening extending from the flow straightening hole to an outside of the valve seat member, the communication opening having an inner diameter smaller than an inner diameter of the flow straightening hole;
The motor-operated valve according to any one of claims 1 to 6. The orifice portion has, in order from the valve seat side, a first hole and a second hole having a larger diameter than the first hole.
The motor-operated valve according to any one of claims 1 to 7 . The orifice portion has, in order from the valve seat side, a first hole, a second hole having a larger diameter than the first hole, and a third hole having a larger diameter than the second hole.
The motor-operated valve according to any one of claims 1 to 8 . A plurality of the straightening holes are formed along a circumferential direction of the orifice portion, and one of the straightening holes is offset in an axial direction of the orifice portion with respect to another of the straightening holes adjacent thereto in the circumferential direction.
The motor-operated valve according to any one of claims 1 to 9 . A plurality of the flow straightening holes are arranged along the axial direction of the orifice portion.
The motor-operated valve according to any one of claims 1 to 10 . A swirling flow generating structure is disposed inside the orifice portion.
The motor-operated valve according to any one of claims 1 to 11 .

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