KR20200110134A - Control valve for variable capacity compressor - Google Patents

Abstract

Provided is a control valve for a variable capacity compressor, capable of effectively discharging foreign matter which has entered a gap between a valve shaft and a valve shaft supporting hole while suppressing inclination of the valve shaft. A control valve (1), which is a control valve for the variable capacity compressor, has a helical groove (36) communicating from a second port (18) to a Ps entrance chamber (16), on the outer peripheral surface (34a) of a trunk unit (34) of the valve shaft (31) in which a main valve body (40) is connected to one end. In addition, as the spiral groove (36) faces from the second port (18) side to the Ps entrance chamber (16), a fluid passage area is formed to gradually increase.

Description

Control valve for variable displacement compressor {CONTROL VALVE FOR VARIABLE CAPACITY COMPRESSOR}

The present invention relates to a control valve for a variable displacement compressor.

As a compressor for an air conditioner mounted on a vehicle, a swash plate type variable capacity compressor is used. This compressor has a swash plate attached to a rotating shaft that is rotationally driven by the vehicle's engine. This swash plate is disposed in the crank chamber, and causes a piston to reciprocate and compress the refrigerant as a fluid. The refrigerant is also introduced into the crank chamber, and the inclination angle of the swash plate changes in response to the pressure Pc of the refrigerant in the crank chamber. The stroke amount of the piston changes according to the inclination angle of the swash plate. The compressor has a discharge chamber for discharging the refrigerant compressed by a piston, and a suction chamber for sucking the refrigerant.

The control valve used in the compressor adjusts the amount of refrigerant supplied from the discharge chamber (refrigerant pressure Pd) to the crank chamber in response to the pressure Ps of the refrigerant in the suction chamber, thereby adjusting the pressure of the refrigerant in the crank chamber (Pc ) To control. The inclination angle of the swash plate is controlled by controlling the pressure Pc of the refrigerant in the crankcase. Thereby, the stroke amount of the piston is increased or decreased to adjust the discharge amount of the refrigerant.

Patent document 1 discloses a control valve for a variable displacement compressor. In the control valve of Patent Document 1, a pressure reducing chamber connected to a suction chamber and a valve chamber connected to the discharge chamber are provided in a valve casing as a valve body. Bellows are arranged in the decompression chamber. Valves are arranged in the valve chamber. This valve body opens and closes the communication path between the discharge chamber and the crank chamber. A valve shaft connected to the valve body is inserted through a valve shaft support hole provided in the valve casing. This control valve moves the valve through the valve shaft in response to the pressure in the suction chamber sensed by the bellows, and adjusts the degree of opening of the communication path between the discharge chamber and the crank chamber.

This control valve is formed so that the valve shaft is tapered and has a smaller diameter from the high pressure side to the low pressure side. As a result, the gap between the outer peripheral surface of the valve shaft and the inner peripheral surface of the valve shaft support hole is formed so that the lower pressure side is larger than the high pressure side in the long side direction of the valve shaft. Therefore, this control valve does not reduce the gap between the valve shaft and the valve shaft support hole even if there is a shift in the shaft center between the valve shaft support hole and the valve shaft due to a machining error or an assembly error. It is supposed to be easily discharged.

Patent Document 1: Japanese Patent No. 4031945

However, in the control valve, since the clearance between the outer circumferential surface of the valve shaft and the inner circumferential surface of the valve shaft support hole becomes large, the valve shaft tends to incline with respect to the valve shaft support hole. Further, if the valve shaft is inclined, there is a fear that the valve cannot properly close the communication path, so that the refrigerant may leak while the valve is closed, or the sliding resistance between the valve shaft and the valve shaft support hole may increase.

Accordingly, an object of the present invention is to provide a control valve for a variable displacement compressor capable of effectively discharging foreign matters entering the gap between the valve shaft and the valve shaft support hole while suppressing the inclination of the valve shaft.

In order to achieve the above object, a control valve for a variable displacement compressor according to an aspect of the present invention includes a valve body provided with a valve chamber, a valve body accommodated in the valve chamber, and a valve shaft connected to the valve body. A control valve for a type compressor, wherein the valve body is connected to a Ps inlet chamber partitioned from the valve chamber, a Pd inlet disposed between the valve chamber and the Ps inlet chamber, and the valve chamber and the Pd inlet, and the valve body A valve port opened and closed by a valve shaft extending from the Pd inlet to the Ps entrance room and slidably supporting the valve shaft is provided, and an outer circumferential surface of the valve shaft or an inner circumferential surface of the valve shaft support hole is provided with the A spiral groove that passes from the Pd inlet to the Ps entrance is provided, and as the spiral groove faces from the Pd inlet to the Ps entrance, the fluid passage area gradually increases or the fluid passage area gradually increases. A control valve for a variable displacement compressor, characterized in that it is.

In the present invention, it is preferable that a plurality of sets of the spiral grooves are provided. In addition, it is preferable that the spiral groove is provided on the outer peripheral surface of the valve shaft.

According to the present invention, the outer peripheral surface of the valve shaft connected to the valve body, or the inner peripheral surface of the valve shaft support hole for slidably supporting the valve shaft, is provided with a helical groove from the Pd inlet to the Ps entrance chamber. In addition, as the spiral groove faces from the Pd inlet side to the Ps entrance chamber side, the fluid passage area gradually increases or the fluid passage area gradually increases. In this way, since the spiral groove becomes wider from the Pd inlet side toward the Ps entrance chamber side, the more fluid flows through the spiral groove. Therefore, when a foreign matter flows through the spiral groove together with the fluid, the foreign matter is difficult to stop in the spiral groove, and can be quickly discharged from the spiral groove. Therefore, while suppressing the inclination of the valve shaft, it is possible to effectively discharge foreign matter that has entered the gap between the valve shaft and the valve shaft support hole.

Further, by providing a plurality of helical grooves, it is possible to increase the chance that foreign matters entering the gap between the valve shaft and the valve shaft support hole reach the helical groove. Therefore, even when a foreign matter enters the gap between the valve shaft and the valve shaft support hole, it can be quickly discharged through the spiral groove.

In addition, since the helical groove is provided on the outer peripheral surface of the valve shaft, a passage for discharging foreign matter can be formed between the valve shaft and the valve shaft support hole by simple processing.

1 is a cross-sectional view of a control valve for a variable displacement compressor according to an embodiment of the present invention.
Figure 2 is an enlarged cross-sectional view of the control valve for the variable displacement compressor of Figure 1;
Fig. 3 is a view showing a valve member included in the control valve for a variable displacement compressor of Fig. 1;
4 is a cross-sectional view showing a configuration of a modified example of the control valve for a variable displacement compressor of FIG. 1.
5 is an enlarged cross-sectional view of the control valve for the variable displacement compressor of FIG. 4.
6 is a cross-sectional view of a seat member of the control valve for the variable displacement compressor of FIG. 4.

Hereinafter, a control valve for a variable displacement compressor according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

1 is a cross-sectional view (longitudinal cross-sectional view) of a control valve for a variable displacement compressor according to an embodiment of the present invention in the axial direction (axis line (L) direction). FIG. 2 is an enlarged cross-sectional view of the valve body and its vicinity of the control valve for a variable displacement compressor of FIG. 1. 3 is a view showing a valve member included in the control valve for a variable displacement compressor of FIG. 1. Fig. 3(a) is a perspective view, and Fig. 3(b) is a front view. 3(c) is a cross-sectional view taken along line A-A of FIG. 3(b).

The control valve for a variable displacement compressor of the present embodiment (hereinafter, simply referred to as “control valve 1”) is used for, for example, a variable displacement type compressor (hereinafter referred to as “compressor” only) mounted on a vehicle. It is a control valve. This control valve 1 adjusts the amount of refrigerant supplied from the discharge chamber to the crank chamber in response to the pressure of the refrigerant in the suction chamber of the compressor.

As shown in FIGS. 1 and 2, the control valve 1 includes a valve body 10, a valve member 30, a sub valve body 50, and a valve body drive unit 60.

The valve body 10 has a valve housing 11, a seat member 12, an end cap 13, and a filter member 14.

The valve housing 11 is generally formed in a cylindrical shape. A cylindrical seat member 12 is fitted inside the valve housing 11. The seat member 12 partitions the space inside the valve housing 11 up and down. The space near the lower side of the valve housing 11 is the valve chamber 15, and the space near the upper side is the Ps entrance room 16 through which the refrigerant having the suction pressure Ps enters and exits.

A first port 17 connected to the valve chamber 15 is provided at the lower end of the valve housing 11. The valve housing 11 and the seat member 12 are provided with a second port 18 disposed between the valve chamber 15 and the Ps entry chamber 16 and penetrating in the transverse direction. A refrigerant having a discharge pressure Pd is introduced into the second port 18. The second port 18 is a Pd inlet. The valve housing 11 is provided with a third port 19 that penetrates in the transverse direction and connects to the Ps entrance chamber 16. The first port 17 is connected to the crankcase of the compressor. The second port 18 is connected to the discharge chamber of the compressor. The third port 19 is connected to the suction chamber of the compressor. During operation of the compressor, the pressure of the refrigerant in the discharge chamber (discharge pressure Pd) is higher than the pressure of the refrigerant in the suction chamber (suction pressure Ps).

The seat member 12 is provided with a valve port 21, a valve seat 22, and a valve shaft support hole 23. The valve port 21 connects the valve chamber 15 and the second port 18. The valve seat 22 is provided so as to surround the valve port 21 on the lower end surface 12a of the seat member 12. The valve shaft support hole 23 is provided through the seat member 12 from the second port 18 to the upper end surface 12b. That is, the valve shaft support hole 23 extends from the second port 18 to the Ps entrance chamber 16. The valve housing 11, the seat member 12, the valve port 21, the valve seat 22, and the valve shaft support hole 23 are coaxially provided so that the respective axes coincide on the axis line (L). have.

The end cap 13 is attached to the valve housing 11 to cover the first port 17. The end cap 13 is provided with a filter 13a. The filter member 14 is attached to the valve housing 11 so as to cover the second port 18.

As shown in FIG. 3, the valve member 30 has the valve shaft 31 and the main valve body 40 integrally.

The valve shaft 31 integrally has a head 32, a neck 33, a trunk 34, and a leg 35, which are sequentially connected coaxially from the top to the bottom. The head 32 is formed in a disk shape. The neck 33 is formed in a cylindrical shape with a smaller diameter than the head 32. The trunk portion 34 is formed in a cylindrical shape slightly larger than the head portion 32. The leg portion 35 is formed in a cylindrical shape having a smaller diameter than the trunk portion 34.

The body portion 34 is inserted into the valve shaft support hole 23 of the seat member 12. Thereby, the valve shaft 31 is supported so as to be slidable in the vertical direction by the valve shaft support hole 23. The diameter of the body portion 34 is slightly smaller than the diameter of the valve shaft support hole 23. Therefore, a gap 26 is provided between the trunk portion 34 and the seat member 12 over the entire circumferential direction.

A spiral groove 36 formed in a spiral shape from the top to the bottom is provided on the outer circumferential surface 34a of the trunk portion 34. One end of the spiral groove 36 is open to the upper end surface 34b of the trunk portion 34. The other end of the spiral groove 36 is open to the lower end surface 34c of the trunk portion 34.

The spiral groove 36 is a spiral groove 36 from the bottom surface 34c side (the second port 18 side) of the trunk portion 34 toward the top surface 34b side (Ps entrance chamber 16). ) Is formed so that the area of the cross-section perpendicular to the extending direction (fluid passage area) gradually increases. Alternatively, the spiral groove 36 is formed so that the fluid passage area of the spiral groove 36 increases step by step (step shape) as it goes from the bottom surface 34c side of the trunk portion 34 to the top surface 34b side. You may have it. The fluid passage area is an area of a cross section in a direction orthogonal to the flow direction of the fluid in the flow path (the direction extending from the spiral groove 36). By doing in this way, since the spiral groove 36 becomes wider as it goes from the lower end surface 34c side to the upper end surface 34b side of the trunk portion 34, the refrigerant flows more easily as the spiral groove 36 proceeds. Lose. Therefore, when a foreign material flows through the spiral groove 36 together with the refrigerant, the foreign material is difficult to stop in the spiral groove 36, and can be quickly discharged from the spiral groove 36. Accordingly, since the valve shaft is formed in a tapered shape to improve the discharging tendency of the foreign matter and there is no need to increase the gap between the valve shaft and the valve shaft support hole, the foreign matter can be effectively discharged while suppressing the inclination of the valve shaft.

In this embodiment, the spiral groove 36 has a U-shaped cross-sectional shape, and is formed so that the width and depth gradually increase from the lower end 34c side to the upper end 34b side. The cross-sectional shape of the spiral groove 36 may be a V-shape or a square shape. The spiral groove 36 may be formed so that only one of the width and the depth gradually increases. Alternatively, the spiral groove 36 may be formed so that the width or depth or the width and depth increase step by step from the lower end 34c side to the upper end 34b side of the trunk portion 34. Alternatively, as the one set of spiral grooves 36 is directed from the bottom side 34c side to the top side side 34b, the fluid passage area may be gradually increased or gradually increased by branching into a plurality of sets.

The upper end surface 34b of the trunk portion 34 faces the Ps entrance chamber 16, and the lower end surface 34c faces the second port 18. Thereby, the spiral groove 36 passes from the second port 18 to the Ps entrance room 16. Therefore, when a pressure difference occurs between the second port 18 and the Ps entrance chamber 16, the refrigerant flows through the gap 26 and the spiral groove 36. When the foreign matter contained in the refrigerant flowing through the gap 26 reaches the spiral groove 36, it flows through the spiral groove 36 after that.

In this embodiment, only one set of spiral grooves 36 is provided, but a plurality of sets of spiral grooves 36 may be provided. By doing in this way, the chance that the foreign matter which has entered the gap 26 between the valve shaft 31 and the valve shaft support hole 23 reaches the spiral groove 36 can be increased. Therefore, even when a foreign material enters the gap between the valve shaft 31 and the valve shaft support hole 23, it can be quickly discharged through the spiral groove 36.

The main valve body 40 has a large-diameter part 41 and a small-diameter part 42 connected to the lower end of the main valve body 40 integrally. The large diameter portion 41 is connected to the lower end (one end of the valve shaft 31) of the leg portion 35 of the valve shaft 31. The large-diameter portion 41 is disposed in the valve chamber 15 to face the valve seat 22 in the vertical direction. The main valve body 40 is pushed upward toward the valve seat 22 by a main valve body valve closing spring 43 made of a conical compression coil spring. As the main valve body 40 moves in the vertical direction, the large diameter portion 41 is separated from the valve seat 22 or comes into contact with the valve seat 22 to open and close the valve port 21. Further, the opening degree of the valve port 21 is adjusted by the distance between the large diameter portion 41 and the valve seat 22. The main valve body 40 is provided coaxially with the valve shaft 31.

The sub-valve body 50 is formed in a cylindrical shape as a whole. The sub-valve body 50 is accommodated in the Ps entrance chamber 16. The sub-valve body 50 has the sub-valve body main body 51, the valve part 52, and the hook part 53 integrally. The sub-valve body main body 51 is formed in a cylindrical shape, and an upper portion of the seat member 12 is inserted inside. The valve portion 52 is formed in a flange shape extending outward in the radial direction over the entire circumference of the lower end of the sub-valve body portion 51. The hook portion 53 is provided to protrude radially inward on a part of the upper end of the sub-valve body portion 51. The sub-valve body 50 moves in the vertical direction so that the valve part 52 comes into contact with the valve housing 11 or is separated from the valve housing 11, so that the seat member 12 and the valve housing 11 Open and close the gap 24 of. The gap 24 is connected to the valve chamber 15 through a connection flow path 25. The sub-valve element 50 is pushed downward by a sub-valve element valve closing spring 54 made of a compression coil spring.

The valve body driving part 60 is attached to the upper part of the valve body 10. The valve body drive unit 60 moves the main valve body 40 and the sub valve body 50 in the vertical direction. The valve body drive unit 60 includes a case 61, a coil unit 62, a suction element 63, an adjustment screw 64, a pipe 65, a bellows 66, and a push rod 67. ), a plunger 68, a coil spring 69, a valve body connecting portion 70, a connector head 73, and a holder 74.

The case 61 is formed in a cylindrical shape. In the case 61, the coil part 62 and the cylindrical suction element 63 are accommodated in order from the outside. The coil portion 62 and the suction element 63 are fixed to the case 61. An adjustment screw 64 is screwed on the upper part of the suction element 63. A cylindrical pipe 65 is coaxially fixed to the lower portion of the suction element 63. A decompression chamber 75 is provided inside the suction element 63. The decompression chamber 75 is connected to the Ps entrance chamber 16 through a pipe 65. In the decompression chamber 75, a bellows 66 as a decompression member is accommodated. The upper end of the bellows 66 abuts the adjustment screw 64. The sensitivity to pressure in the bellows 66 is adjusted by the amount of screwing of the adjusting screw 64 to the suction element 63.

The upper end of the push rod 67 is inserted into a recess 66a provided at the lower end of the bellows 66. The lower end of the push rod 67 is inserted into an insertion hole 68a provided in the bottom wall of the cylindrical plunger 68 with a bottom. A flange 67a is provided in the middle of the push rod 67. A plunger spring 69 made of a compression coil spring is disposed between the flange 67a and the plunger 68. The plunger spring 69 pushes the plunger 68 downward and pushes the push rod 67 upward toward the bellows 66.

The plunger 68 is fixed to the inside of the bottomed cylindrical valve body connection 70. The plunger 68 and the valve body connection part 70 are accommodated in the pipe 65 so as to be movable in the vertical direction. The disk-shaped bottom wall portion 71 of the valve body connection portion 70 is provided with a slit 71a extending from the periphery to the center in the radial direction (left and right directions in FIG. 1). The width of the slit 71a is smaller than the head 32 of the valve shaft 31 and larger than the neck 33. The neck 33 of the valve shaft 31 is inserted into the slit 71a. The thickness of the bottom wall portion 71 is smaller than the length of the neck portion 33 in the axial line L direction, and the valve shaft 31 is movable in the vertical direction with respect to the bottom wall portion 71. In addition, the bottom wall portion 71 is provided with a foot portion 72 extending downward. The foot part 72 has a shape in which a part of the cylinder is notched along the axial direction. The lower end of the foot portion 72 is provided with a protrusion 72a protruding outward in the radial direction. The protrusion 72a is disposed to face the hook portion 53 of the sub-valve body 50 in the direction of the axis L.

A connector head 73 is attached to the upper part of the case 61 by caulking. A lead wire (not shown) for supplying power to the coil unit 62 is connected to the connector head 73. The holder 74 is formed in an annular shape. The lower end of the case 61 is fixed to the upper part of the holder 74 by welding or the like. Inside the holder 74, the lower end of the pipe 65 is fitted from above, and the upper end of the valve housing 11 is fitted from the lower side. The holder 74 and the valve housing 11 are fixed by pressing or the like.

In a state in which the coil unit 62 is not energized (off state), the valve element drive unit 60 is provided with the valve unit 52 of the sub-valve unit 50 as shown in Figs. In contact with ), the gap 24 between the seat member 12 and the valve housing 11 is closed.

In the state in which the coil unit 62 is energized (on state), the valve element drive unit 60 moves the plunger 68 and the valve element connection unit 70 upward by the magnetic force generated by the suction element 63. When the valve body connection part 70 moves upward, the main valve body 40 also moves upward by the main valve body valve closing spring 43 and the valve port 21 is closed. In addition, when the valve body connection part 70 moves upward and the large diameter part 41 of the main valve body 40 abuts the valve seat, the protrusion 72a of the foot part 72 becomes the hook of the sub-valve body 50 By being caught in the part 53, the sub-valve body 50 also moves upward, and the gap 24 opens. Thereby, the valve chamber 15 and the Ps entrance chamber 16 are connected by the connection flow path 25.

The control valve 1 is turned on when the compressor is started to connect the crank chamber (valve chamber 15) and the suction chamber (Ps entry chamber 16) of the compressor. Thereby, the time required until the discharge capacity becomes large can be shortened. Further, by turning off the compressor during normal operation, since the connection between the crank chamber and the suction chamber of the compressor is cut, it is possible to prevent a decrease in the operating efficiency of the compressor.

As described above, according to the control valve 1 of the present embodiment, the outer peripheral surface 34a of the trunk portion 34 of the valve shaft 31 to which the main valve body 40 is connected to the lower end is provided from the second port 18 to Ps. A spiral groove 36 leading to the access room 16 is provided. In addition, as the spiral groove 36 faces from the second port 18 side to the Ps entrance chamber 16 side, the fluid passage area is formed to gradually increase. In this way, since the spiral groove 36 becomes wider from the second port 18 side toward the Ps entrance chamber 16 side, the refrigerant flows more easily as the spiral groove 36 proceeds. Therefore, when a foreign material flows through the spiral groove 36 together with the refrigerant, the foreign material is difficult to stop in the spiral groove 36, and can be quickly discharged from the spiral groove 36. Therefore, while suppressing the inclination of the valve shaft 31, foreign matters entering the gap 26 between the valve shaft 31 and the valve shaft support hole 23 can be effectively discharged.

4 to 6 show a control valve 1A that is a modified example of the control valve 1 of the present embodiment described above.

4 is a longitudinal sectional view showing a configuration of a modified example of the control valve for a variable displacement compressor of FIG. 1. 5 is an enlarged cross-sectional view of the valve member and its vicinity of the control valve for a variable displacement compressor of FIG. 4. 6 is a longitudinal sectional view of a seat member included in the control valve for the variable displacement compressor of FIG. 4.

In the control valve 1 of the present embodiment described above, the control valve 1A is Ps from the second port 18 to the inner peripheral surface of the valve shaft support hole 23 in place of (i) the spiral groove 36 A spiral groove 29 leading to the thread 16 is provided, (ii) an oil reservoir groove 37 is provided under the outer circumferential surface 34a of the trunk portion 34 of the valve shaft 31, except for control It has the same configuration as the valve 1. The oil reservoir groove 37 collects oil contained in the refrigerant and seals the gap 26 by the surface tension thereof, thereby suppressing the flow of the refrigerant through the gap 26.

One end of the spiral groove 29 is open to the upper end surface 12b of the sheet member 12. The other end of the spiral groove 29 is open on the inner peripheral surface of the second port 18 of the sheet member 12. Thereby, the spiral groove 29 passes from the second port 18 to the Ps entrance chamber 16.

The spiral groove 29 has a U-shaped cross-sectional shape and is formed to gradually increase in width and depth from the second port 18 side to the top surface 12b side (Ps entrance chamber 16 side). have. In addition to the U-shaped cross-section, the spiral groove 29 may be formed in a V-shaped cross-section or a rectangular cross-sectional shape. The spiral groove 29 may be formed so that only one of the width and depth gradually increases. Alternatively, the spiral groove 29 may be formed so that the width or depth or the width and depth increase step by step from the second port 18 side toward the top surface 12b side. Alternatively, a set of spiral grooves 29 may be branched into a plurality of sets as they are directed from the second port 18 side to the top surface 12b side.

The control valve 1A also has the same effect as the control valve 1 of the present embodiment described above.

Although the embodiments of the present invention have been described above, the present invention is not limited to these examples. Those skilled in the art to appropriately add, delete, or change the design of the above-described embodiments, and appropriate combinations of features of the embodiments are also included in the scope of the present invention unless contrary to the spirit of the present invention.

1, 1A: control valve 10: valve body
11: valve housing 12: seat member
12a: bottom side 12b: top side
13: end cap 13a: filter
14: filter member 15: valve chamber
16: Ps access room 17: 1st port
18: second port 19: third port
21: valve port 22: valve seat
23: valve shaft support hole 24: clearance
25: connection flow path 26: clearance between the valve shaft and the valve shaft support hole
29: spiral groove 30: valve member
31: valve shaft 32: head
33: neck 34: trunk
34a: outer peripheral surface 34b: upper surface
34c: lower surface 35: leg portion
36: spiral groove 40: main valve body
43: main valve body valve closing spring 50: sub valve body
51: sub-valve body main body 52: valve part
53: hook portion 54: sub-valve body valve closing spring
60 valve body drive unit 61 case
62: coil unit 63: aspirator
64: adjustment screw 65: pipe
66: bellows 66a: concave
67: push rod 67a: flange
68: plunger 8a: insertion hole
69: plunger spring 70: valve body connection
71: bottom wall portion 71a: slit
72: foot part 72a: protrusion
73: connector head 74: holder
75: decompression chamber

Claims (3)

A control valve for a variable displacement compressor having a valve body provided with a valve chamber, a valve body accommodated in the valve chamber, and a valve shaft connected to the valve body,
The valve body includes a Ps inlet chamber partitioned from the valve chamber, a Pd inlet disposed between the valve chamber and the Ps inlet chamber, and a valve port connected to the valve chamber and the Pd inlet, and opened and closed by the valve body. , A valve shaft support hole extending from the Pd inlet to the Ps entrance room and supporting the valve shaft to be slidably provided,
A spiral groove is provided on the outer circumferential surface of the valve shaft or the inner circumferential surface of the valve shaft support hole from the Pd inlet to the Ps inlet,
A control valve for a variable displacement compressor, characterized in that the spiral groove is formed to gradually increase the fluid passage area or increase stepwise as the spiral groove faces from the Pd inlet side to the Ps entrance chamber side. The method of claim 1,
A control valve for a variable displacement compressor, characterized in that a plurality of spiral grooves are provided. The method according to claim 1 or 2,
The control valve for a variable displacement compressor, characterized in that the spiral groove is provided on the outer peripheral surface of the valve shaft.

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