Capacity Control Valve

Abstract

Provided is a capacity control valve which is capable of operating efficiently while having a fluid discharge function at startup.　A capacity control valve V comprising: a valve housing 10 that has formed therein a discharge port 12, intake ports 13, 15, and a control port 14; and a main valve 50 formed of a main valve body 51 which is driven by a solenoid 80 and a main valve seat 10a which is provided between the discharge port 12 and the control port 14 and with which the main valve body 51 is capable of coming into contact, wherein the capacity control valve is provided with a CS valve 57 which has a CS valve body 56 having a communication hole 56f formed therein and being configured to slidably move on the valve housing 10 in conjunction with the main valve body 51, and in which the communication hole 56f makes it possible for a flow channel between the control port 14 and the intake port 15 to establish connection in accordance with the slide position of the CS valve body 56.

Description

[Technical field]

[0001] The present invention relates to a displacement control valve that variably controls the volume of a working fluid, and more particularly to a displacement control valve that controls the discharge volume of a variable displacement compressor used in an automotive air conditioning system in accordance with pressure. [Background technology]

[0002] A variable displacement compressor used in air conditioning systems for automobiles and the like includes a rotating shaft driven by an engine, a swash plate connected to the rotating shaft with a variable inclination angle, and a compression piston connected to the swash plate, and controls the amount of fluid discharged by changing the inclination angle of the swash plate to change the stroke amount of the piston. The inclination angle of the swash plate can be continuously changed by appropriately controlling the pressure in the control chamber using the suction pressure Ps in the suction chamber that draws in the fluid, the discharge pressure Pd in ​​the discharge chamber that discharges the fluid pressurized by the piston, and the control pressure Pc in the control chamber that houses the swash plate, using a displacement control valve that is opened and closed by electromagnetic force.

[0003] When the variable displacement compressor is in continuous operation, the displacement control valve is energized and controlled by the control computer. The valve element is moved axially by the electromagnetic force generated by the solenoid, and the main valve provided between the discharge port through which the discharge fluid at discharge pressure Pd passes and the control port through which the control fluid at control pressure Pc passes is opened and closed to perform normal control to adjust the control pressure Pc in the control chamber of the variable displacement compressor.

[0004] During normal control of the capacity control valve, the pressure in the control chamber of the capacity control compressor is appropriately controlled, and the inclination angle of the swash plate relative to the rotating shaft is continuously changed to change the stroke amount of the piston and control the amount of fluid discharged into the discharge chamber, thereby adjusting the air conditioning system to achieve the target cooling capacity. When the capacity control compressor is driven at maximum capacity, the main valve of the capacity control valve is closed to reduce the pressure in the control chamber, thereby maximizing the inclination angle of the swash plate.

[0005] In addition, a device is also known in which an auxiliary communication passage is formed to connect the control port and suction port of a displacement control valve, and upon startup, refrigerant in the control chamber of the variable displacement compressor is discharged through the control port, the auxiliary communication passage, and the suction port into the suction chamber of the variable displacement compressor, thereby quickly reducing the pressure in the control chamber upon startup, thereby improving the responsiveness of the variable displacement compressor (see Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5167121 (page 7, figure 2) Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the case of Patent Document 1, although the fluid discharge function at the time of startup is excellent, when the variable displacement compressor is continuously driven, the auxiliary communication passage is connected and the refrigerant flows from the control port to the suction port, so that the amount of refrigerant circulating is large, and there is a risk that the operating efficiency of the variable displacement compressor will decrease.

[0008] The present invention has been made in view of the above problems, and has an object to provide a displacement control valve which has a fluid discharge function at start-up and which operates efficiently. [Means for solving the problem]

[0009] In order to solve the above problems, the capacity control valve of the present invention comprises: a valve housing having a discharge port through which a discharge fluid having a discharge pressure passes, a suction port through which a suction fluid having a suction pressure passes, and a control port through which a control fluid having a control pressure passes; A capacity control valve including: a main valve including a main valve element driven by a solenoid; and a main valve seat provided between the discharge port and the control port and contactable by the main valve element, The CS valve has a CS valve body having a communicating hole formed therein and sliding in the valve housing in conjunction with the main valve body, and the communicating hole enables communication between the flow passages between the control port and the suction port depending on the sliding position of the CS valve body. According to this, the CS valve has a spool valve structure, and the rate of increase in the aperture of the communication hole relative to the valve body stroke from the time before the fully open state to the fully open state can be made larger than the rate of increase from the fully closed state to the time before the fully open state starts to open, so that when the solenoid in the displacement control valve is not energized, the main valve is fully open and the CS valve is fully closed. As a result, during normal control of the displacement control valve, the rate of increase in the aperture of the communication hole from the time the CS valve starts to open is small, so there is little fluid leakage and the operating efficiency of the displacement control valve is high. Also, when the displacement control compressor is started, the main valve is fully closed and the CS valve is fully open, and the control port and the suction port are communicated, so that the liquefied fluid in the control chamber is discharged into the suction chamber through the communication hole in a short time. In this way, the displacement control valve can improve the responsiveness of the displacement control compressor at the time of starting up.

[0010] The CS valve body may be formed as a separate member that is separable from the main valve body. With this, the main valve body and the CS valve body can be aligned independently, thereby minimizing the influence on each other's operation and enabling the opening of the main valve and the CS valve to be adjusted with high precision.

[0011] The main valve body and the CS valve body may be capable of abutting against each other only in the axial direction. This reduces the influence on the operation of the main valve body and the CS valve body caused by the inclination or misalignment of their axial centers.

[0012] The CS valve element may be biased in a closing direction by a spring. According to this, since the CS valve element follows the main valve element when the main valve is opened, the communication hole of the CS valve can be reliably closed.

[0013] The communication hole may be a hole penetrating in the radial direction, and the opening shape may be formed from a part of a circle. This allows the opening of the communication hole to be gradually increased in accordance with the stroke of the valve disc.

[0014] The opening shape of the communication hole may be circular. This makes it easier to process and form the communication hole in the CS valve body. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram showing a configuration of a swash plate type variable displacement compressor in which a displacement control valve according to an embodiment of the present invention is incorporated; [Diagram 2] 1 is a cross-sectional view showing a state in which the main valve is fully opened and the communication hole is closed by the CS valve in a non-energized state of the displacement control valve of the embodiment. FIG. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of FIG. 2. [Figure 4] 4 is an enlarged cross-sectional view showing a state in which a communication hole starts to open from a fully closed state by a CS valve in a current-carrying state (during normal control) of the displacement control valve of the embodiment. FIG. [Diagram 5] 1 is an enlarged cross-sectional view showing a state in which the main valve is closed and the communication hole is fully opened by the CS valve in a maximum current-carrying state (at start-up) of the displacement control valve of the embodiment. FIG. [Figure 6] 2 is a diagram for explaining the opening areas of the main valve and the CS valve (communication hole) relative to the stroke position of the main and sub-valve bodies of the embodiment. Note that the stroke position on the horizontal axis is shown in the direction in which the main and sub-valve bodies move when a current is applied to the solenoid (from right to left in FIG. 2). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A capacity control valve according to an embodiment of the present invention will be described below with reference to the accompanying drawings. EXAMPLES

[0017] A displacement control valve according to an embodiment will be described with reference to Figures 1 to 6. In the following description, the left and right sides as viewed from the front side of Figure 2 are the left and right sides of the displacement control valve.

[0018] The capacity control valve V of the present invention is incorporated in a variable capacity compressor M used in the air conditioning system of an automobile or the like. The capacity control valve V variably controls the pressure of a working fluid (hereinafter simply referred to as "fluid"), which is a refrigerant, in the variable capacity compressor M. In this way, the capacity control valve V controls the discharge amount of the variable capacity compressor M, and adjusts the air conditioning system to achieve a desired cooling capacity.

[0019] First, the variable displacement compressor M will be described. As shown in Fig. 1, the variable displacement compressor M has a casing 1 including a discharge chamber 2, a suction chamber 3, a control chamber 4, and a plurality of cylinders 4a. The variable displacement compressor M is provided with a communication passage (not shown) that directly connects the control chamber 4 and the suction chamber 3. This communication passage is provided with a fixed orifice for balancing the pressures of the suction chamber 3 and the control chamber 4.

[0020] The variable displacement compressor M includes a rotating shaft 5, a swash plate 6, and a plurality of pistons 7. The rotating shaft 5 is driven to rotate by an engine (not shown) installed outside the casing 1. The swash plate 6 is inclinably connected to the rotating shaft 5 in the control chamber 4 by a hinge mechanism 8. The plurality of pistons 7 are connected to the swash plate 6 and fitted in the cylinders 4a so as to be capable of reciprocating motion. The pressure in the control chamber 4 of the variable displacement compressor M is appropriately controlled by opening and closing the capacity control valve V by an electromagnetic force, using the suction pressure Ps of the suction chamber 3 that sucks in the fluid, the discharge pressure Pd of the discharge chamber 2 that discharges the fluid pressurized by the pistons 7, and the control pressure Pc of the control chamber 4 that accommodates the swash plate 6. As a result, the inclination angle of the swash plate 6 changes continuously. The stroke amount of the pistons 7 changes accordingly, and the discharge amount of the fluid from the variable displacement compressor M is controlled. For ease of explanation, a displacement control valve V incorporated in the variable displacement compressor M is omitted in FIG.

[0021] Specifically, the higher the control pressure Pc in the control chamber 4, the smaller the inclination angle of the swash plate 6 with respect to the rotating shaft 5, and the smaller the stroke amount of the piston 7. When the control pressure Pc reaches a certain level or higher, the swash plate 6 is in a substantially vertical state with respect to the rotating shaft 5, that is, in a state where it is slightly inclined from the vertical. At this time, the stroke amount of the piston 7 is minimized, and the pressurization of the fluid in the cylinder 4a by the piston 7 is minimized. As a result, the amount of fluid discharged to the discharge chamber 2 is reduced, and the cooling capacity of the air conditioning system is minimized. On the other hand, the lower the control pressure Pc in the control chamber 4, the larger the inclination angle of the swash plate 6 with respect to the rotating shaft 5, and the larger the stroke amount of the piston 7. When the control pressure Pc reaches a certain level or lower, the inclination angle of the swash plate 6 with respect to the rotating shaft 5 is maximized. At this time, the stroke amount of the piston 7 is maximized, and the pressurization of the fluid in the cylinder 4a by the piston 7 is maximized. As a result, the amount of fluid discharged to the discharge chamber 2 is increased, and the cooling capacity of the air conditioning system is maximized.

[0022] As shown in Fig. 2, the displacement control valve V is incorporated in a variable displacement compressor M. The main valve 50, sub-valve 55, and CS valve 57 in the displacement control valve V are controlled to open and close by adjusting the current flowing through a coil 86 constituting a solenoid 80. At the same time, the pressure sensing element 61 is operated by the suction pressure Ps in the intermediate communication passage 59, thereby controlling the opening and closing of the pressure sensing valve 53. In this way, the fluid flowing into or out of the control chamber 4 is controlled. Utilizing this, the control pressure Pc in the control chamber 4 is variably controlled.

[0023] In this embodiment, the main valve 50 is composed of a main and sub-valve body 51 as a main valve body and a main valve seat 10a. The main valve seat 10a is formed on the inner peripheral surface of the valve housing 10. The main valve 50 opens and closes when the axial left end surface 51a of the main and sub-valve body 51 comes into contact with and separates from the main valve seat 10a. The pressure-sensitive valve 53 is composed of a cap 70 and a pressure-sensitive valve seat 52a. The cap 70 is also a member that constitutes the pressure-sensitive body 61. The pressure-sensitive valve seat 52a is formed on the axial left end surface of the pressure-sensitive valve member 52. The pressure-sensitive valve 53 opens and closes when the seal surface 70a formed on the inner diameter side at the axial right end of the cap 70 comes into contact with and separates from the pressure-sensitive valve seat 52a. The sub-valve 55 is composed of the main and sub-valve body 51 and a sub-valve seat 82a. The sub-valve seat 82a is formed on the opening end surface of the fixed iron core 82, i.e., the axial left end surface. The sub-valve 55 opens and closes when the axial right end face 51b of the main sub-valve element 51 moves toward and away from the sub-valve seat 82a. The CS valve 57 is composed of a CS valve element 56 and a guide surface 10e. The guide surface 10e is formed on the inner circumferential surface of the valve housing 10. The outer circumferential surface 56a of the CS valve element 56 slides axially against the guide surface 10e to open and close a communication hole 56f (see Figures 3 to 5) provided in the CS valve element 56. The CS valve 57 will be described in detail later.

[0024] Next, the structure of the displacement control valve V will be described. As shown in FIG. 2, the displacement control valve V is mainly composed of a valve housing 10, a main and sub-valve body 51, a pressure-sensitive valve member 52, a contact member 54, a CS valve body 56, a pressure-sensitive body 61, and a solenoid 80. The valve housing 10 is made of a metal material or a resin material. The main and sub-valve body 51, the pressure-sensitive valve member 52, the contact member 54, and the CS valve body 56 are arranged in the valve housing 10 so as to be able to reciprocate in the axial direction. The pressure-sensitive body 61 applies a biasing force to the main and sub-valve body 51, the pressure-sensitive valve member 52, and the contact member 54 in the axial rightward direction in response to the suction pressure Ps in the intermediate communication passage 59. The solenoid 80 is connected to the valve housing 10 and exerts a driving force on the main and sub-valve body 51, the pressure-sensitive valve member 52, the contact member 54, and the CS valve body 56.

[0025] As shown in FIG. 2, the solenoid 80 is mainly composed of a casing 81, a fixed core 82, a driving rod 83, a movable core 84, a coil spring 85, and a coil 86. The casing 81 has an opening 81a that opens to the left in the axial direction. The fixed core 82 is formed in a substantially cylindrical shape, inserted into the opening 81a in the casing 81 from the left in the axial direction, and fixed to the inner diameter side of the casing 81. The driving rod 83 is reciprocable in the axial direction on the inner diameter side of the fixed core 82, and its axial left end is connected and fixed to the axial right end of the main / sub-valve body 51. The movable core 84 is fixed to the axial right end of the driving rod 83. The coil spring 85 is provided between the fixed core 82 and the movable core 84 and biases the movable core 84 to the right in the axial direction. The excitation coil 86 is wound around the outside of the fixed core 82 via a bobbin.

[0026] A recess 81b recessed axially rightward is formed on the inner diameter side of the axial left end portion of the casing 81. In the casing 81, the axial right end portion of the valve housing 10 is inserted and fixed into the recess 81b in a substantially sealed manner.

[0027] The fixed core 82 is formed of a rigid body that is a magnetic material such as iron or silicon steel. The fixed core 82 includes a cylindrical portion 82b and a flange portion 82d. The cylindrical portion 82b is formed with an insertion hole 82c that extends in the axial direction and through which the drive rod 83 is inserted. The flange portion 82d is annular and extends radially outward from the outer circumferential surface of the left end portion of the cylindrical portion 82b in the axial direction. In addition, an auxiliary valve seat 82a is formed on the left end surface of the cylindrical portion 82b in the axial direction.

[0028] 2, the valve housing 10 is formed with, in order from the solenoid 80 side, a Pd port 12 as a discharge port, a first Ps port 13 as a suction port, a Pc port 14 as a control port, and a second Ps port 15 as a suction port. The Pd port 12 communicates with the discharge chamber 2 of the variable displacement compressor M. The first Ps port 13 communicates with the suction chamber 3 of the variable displacement compressor M. The Pc port 14 communicates with the control chamber 4 of the variable displacement compressor M. The second Ps port 15 communicates with the suction chamber 3 of the variable displacement compressor M.

[0029] The valve housing 10 has a generally cylindrical shape with a bottom, with a partition adjustment member 11 press-fitted into the left axial end portion of the valve housing 10 in a generally sealed manner. By adjusting the axial installation position of the valve housing 10, the partition adjustment member 11 is capable of adjusting the biasing force of a coil spring 91, which serves as a spring and will be described later.

[0030] Inside the valve housing 10, the main and auxiliary valve element 51, the pressure-sensitive valve member 52, the abutment member 54, and the CS valve element 56 are arranged so as to be freely reciprocable in the axial direction. A small-diameter guide surface 10b is formed on the inner peripheral surface of the valve housing 10 between the first Ps port 13 and the Pd port 12, against which the outer peripheral surface of the main and auxiliary valve element 51 can slide in a substantially sealed state. An annular step portion 10f having a substantially hat-shaped axial cross section is formed on the left end of the inner peripheral surface of the valve housing 10 in the axial direction (see Figs. 3 to 5). The annular step portion 10f is formed by an inner peripheral surface 10c, an annular groove 10d, and a guide surface 10e. The inner peripheral surface 10c extends axially rightward from the left end face of the valve housing 10 in the axial direction. The guide surface 10e is formed on the inner peripheral surface extending axially rightward from the right end of the annular groove 10d in the axial direction. The guide surface 10e also functions as a valve seat that comes into sliding contact with the outer circumferential surface 56a of the CS valve body 56. The second Ps port 15 described above is formed at the bottom of the annular groove 10d.

[0031] In addition, a first valve chamber 20, a second valve chamber 30, and a pressure sensing chamber 40 are formed inside the valve housing 10. The first valve chamber 20, the second valve chamber 30, and the pressure sensing chamber 40 are connected to a Pd port 12, a first Ps port 13, and a Pc port 14, respectively. The first valve chamber 20 is located at the axial left end face 51a side of the main sub-valve element 51. The second valve chamber 30 is located at the back pressure side, i.e., the axial right end face 51b side, of the main sub-valve element 51. The pressure sensing element 61 and the CS valve element 56 are located in the pressure sensing chamber 40. The second valve chamber 30 is defined by the outer peripheral surface of the main sub-valve element 51, the axial left end face of the fixed core 82, and the inner peripheral surface of the valve housing 10 on the axial right side of the guide surface 10b.

[0032] 2, the pressure sensing body 61 is mainly composed of a bellows core 62 and a cap 70. A coil spring 63 is built into the bellows core 62. The cap 70 is disk-shaped and is provided at the right end in the axial direction of the bellows core 62. The left end in the axial direction of the bellows core 62 is fixed to the partition adjustment member 11.

[0033] The pressure sensing body 61 is disposed within the pressure sensing chamber 40. The coil spring 63 and the bellows core 62 apply a biasing force to move the cap 70 axially rightward, causing the seal surface 70a of the cap 70 to seat on the pressure sensing valve seat 52a of the pressure sensing valve member 52.

[0034] 2 and 3, the main and sub-valve element 51 is configured to have a substantially cylindrical shape. The pressure-sensitive valve member 52 is connected and fixed to the left axial end of the main and sub-valve element 51. The drive rod 83 is connected and fixed to the right axial end of the main and sub-valve element 51. Both of these are adapted to move in the axial direction. Note that a minute gap is formed between the outer circumferential surface of the main and sub-valve element 51 and the guide surface 10b of the valve housing 10 by slightly separating them in the radial direction. This gap allows the main and sub-valve element 51 to slide against the valve housing 10 and move smoothly relative to it in the axial direction.

[0035] In addition, an intermediate communication passage 59 is formed inside the main / auxiliary valve body 51 and the pressure-sensitive valve member 52 by connecting the hollow holes. The intermediate communication passage 59 can communicate with the second valve chamber 30 through a communication hole 83a formed at the left end of the drive rod 83 in the axial direction (see FIG. 2). Although not shown for convenience of explanation, the fluid that has become high pressure in the control chamber 4 may liquefy when the variable displacement compressor M is left in a stopped state for a long time. In such a state, by starting the variable displacement compressor M and energizing the capacity control valve V, the main valve 50 is closed and the auxiliary valve 55 is opened in the capacity control valve V. Furthermore, the pressure sensing body 61 contracts due to the high suction pressure Ps in the intermediate communication passage 59, and the pressure sensing valve 53 is opened. As a result, the liquid refrigerant in the control chamber 4 is discharged to the suction chamber 3 through the intermediate communication passage 59 in a short time.

[0036] As shown in Figs. 3 to 5, the pressure-sensitive valve member 52 is configured in a flanged, generally cylindrical shape having a first cylindrical portion 52b, a flange portion 52c, a second cylindrical portion 52d, and an abutment portion 52e. The first cylindrical portion 52b is connected and fixed to the main / auxiliary valve body 51 at its left axial end. The flange portion 52c is formed in an annular shape extending radially outward from the outer peripheral surface of the left axial end of the first cylindrical portion 52b. The second cylindrical portion 52d is formed to have a smaller diameter than the flange portion 52c on the axial left side of the flange portion 52c, and is connected and fixed to the abutment member 54 at its right axial end. The abutment portion 52e is formed to have a smaller diameter than the second cylindrical portion 52d on the axial left side of the second cylindrical portion 52d. The abutment portion 52e is formed with a pressure-sensitive valve seat 52a that comes into contact with and separates from the seal surface 70a of the cap 70 constituting the pressure-sensitive body 61.

[0037] As shown in Figs. 3 to 5, the abutment member 54 is formed in a substantially cylindrical shape. The abutment member 54 is formed to have a larger diameter than the cap 70 constituting the pressure-sensing body 61. The second cylindrical portion 52d of the pressure-sensitive valve member 52 is connected and fixed to the axial right end of the abutment member 54. This allows both the main and sub-valve bodies 51 and the pressure-sensitive valve member 52 to move in the axial direction. The axial left end surface 54a of the abutment member 54 abuts in the axial direction on the bottom surface of a recess 56c formed in the axial right end of the CS valve body 56. The axial left end of the abutment member 54 is provided with a through hole 54b penetrating in the radial direction. The through hole 54b communicates the inner diameter side and the outer diameter side of the abutment member 54 in the pressure-sensing chamber 40.

[0038] As shown in Figs. 3 to 5, the CS valve body 56 is configured in a stepped cylindrical shape by a base portion 56b, a recessed portion 56c, an extending portion 56d, and a protruding portion 56e. The base portion 56b is arranged concentrically in the pressure sensing chamber 40 with a diameter larger than that of the pressure sensing body 61, and is formed in a substantially cylindrical shape. The recessed portion 56c is formed in an annular shape with the inner diameter side of the axial right end of the base portion 56b recessed axially leftward. The extending portion 56d is formed in a substantially cylindrical shape extending axially leftward from the outer diameter side at the axial left end of the base portion 56b. The protruding portion 56e is formed in an annular shape protruding in the outer diameter direction from the outer peripheral surface of the axial left end of the extending portion 56d.

[0039] Incidentally, minute gaps are formed by radial separation between the outer circumferential surface 56a of the CS valve body 56, i.e., the outer circumferential surface of the base portion 56b and the guide surface 10e formed on the inner circumferential surface of the valve housing 10, and between the outer circumferential surface of the protruding portion 56e and the inner circumferential surface 10c of the valve housing 10. These gaps allow the CS valve body 56 to slide against the valve housing 10 and move smoothly relative to it in the axial direction.

[0040] Furthermore, a sealing portion Sa formed by a clearance seal is formed between the outer circumferential surface 56a of the CS valve body 56, i.e., the outer circumferential surface of the base portion 56b, and the guide surface 10e of the valve housing 10. Further, a sealing portion Sb formed by a clearance seal is formed between the outer circumferential surface of the protruding portion 56e and the inner circumferential surface 10c of the valve housing 10. That is, sealing portions Sa and Sb are formed on both axial sides of the second Ps port 15, respectively.

[0041] In addition, the CS valve body 56 is provided with a protrusion 56e. As a result, an annular space 60 is formed between the valve housing 10 and the CS valve body 56. The space 60 is sealed from the pressure sensing chamber 40 by sealing portions Sa and Sb, and is in communication with the suction chamber 3 of the variable displacement compressor M by the second Ps port 15.

[0042] In addition, a plurality of communication holes 56f are provided in the axially central portion of the base 56b of the CS valve body 56, penetrating in the radial direction. The plurality of communication holes 56f are capable of communicating the pressure sensing chamber 40 and the space 60 on the inner diameter side and the outer diameter side of the CS valve body 56. The communication holes 56f are formed as through holes with a circular opening shape (see the balloons in Figs. 3 to 5) and a constant inner diameter. This makes it easier to process and form the communication holes 56f in the CS valve body 56. The opening shape of the communication holes 56f is not limited to a circle, and may be formed from a part of a circle, such as a semicircle, or may be formed in a shape other than a circle, such as a triangle or an ellipse.

[0043] Furthermore, the axial left end surface 54a of the abutment member 54 abuts in the axial direction against the bottom surface of a recess 56c formed at the axial right end of the CS valve body 56. The inner diameter of the inner circumferential surface of the recess 56c is formed to be larger than the outer diameter of the abutment member 54. As a result, the abutment member 54 abuts only in the axial direction against the bottom surface of the recess 56c while being spaced from the inner circumferential surface of the recess 56c toward the inner diameter side.

[0044] A recess 56g is formed on the inside of the CS valve body 56 at the axial left end due to the difference in inner diameter between the base portion 56b and the extension portion 56d. The axial right end of a coil spring 91 is fitted into the recess 56g. The coil spring 91 constitutes the pressure sensing body 61 and the CS valve 57.

[0045] The right axial end of the coil spring 91 abuts against the bottom surface of the recess 56g. The left axial end of the coil spring 91 abuts against the bottom surface of the recess 11b formed on the inner diameter side of the partition adjustment member 11. As a result, the coil spring 91 biases the CS valve body 56 axially rightward, which is the valve closing direction of the CS valve 57. The coil spring 91 is a compression spring.

[0046] Furthermore, the axial left end of the CS valve body 56, that is, the axial left end 56h of the extension portion 56d, can approach the axial right end face 11a of the partition adjustment member 11 when the CS valve 57 is open (see FIG. 5).

[0047] Next, the opening and closing mechanism of the CS valve 57 will be described. As shown in Fig. 3, when the main valve 50 is in the open position of the main / sub-valve body 51 where the main valve 50 is fully opened when the solenoid 80 is not energized, the CS valve body 56 is biased by the coil spring 91 in the axial right direction (indicated by the white arrow in Fig. 3) in the valve closing direction. At this time, the communication hole 56f is spaced axially rightward from the axial right end of the annular groove 10d in the valve housing 10. In addition, the bottom surface of the recess 56c abuts against the axial left end surface 54a of the abutment member 54. In addition, the outer peripheral surface 56a of the CS valve body 56 forms a sealing portion Sa by a clearance seal with the guide surface 10e at least on the axial left side around the entire circumference of the communication hole 56f. In other words, the communication hole 56f is fully closed by the sealing portion Sa. Furthermore, a sealing portion Sb is formed by a clearance seal between the outer peripheral surface of the protruding portion 56e of the CS valve body 56 and the inner peripheral surface 10c of the valve housing 10. In this manner, the CS valve 57 is fully closed by the sealing portions Sa and Sb. Note that the balloon display portions in Figures 3 to 5 show the opening degree of the communication hole 56f as viewed from the inner diameter side of the CS valve body 56, i.e., the opening degree of the CS valve 57. Also, in the balloon display portions in Figures 3 to 5, the blocking portion of the opening of the communication hole 56f in the CS valve 57 by the sealing portion Sa is shown by dots.

[0048] When the solenoid 80 is energized while the main valve 50 is in an open state, the main and sub-valve element 51 moves to the left in the axial direction. As shown in FIG. 4, the leftward movement of the main and sub-valve element 51 causes the pressure-sensitive valve member 52, the abutting member 54, and the CS valve element 56 to be pushed to the left in the axial direction and to move together. In response to this movement, the coil spring 91 contracts. As a result, the communication hole 56f is fully closed by the sealing portion Sa of the CS valve 57 until the stroke position P (see FIG. 6) is reached, that is, until the stroke position P is reached where the axial left end of the communication hole 56f in the CS valve element 56 radially overlaps with the axial right end of the annular groove 10d. Then, when the main and sub-valve element 51 moves further leftward from the stroke position P, the pressure-sensitive valve member 52, the abutting member 54, and the CS valve element 56 are further pushed to the left in the axial direction and to move together. In response to this, the coil spring 91 contracts further. As a result, the communication hole 56f begins to open. That is, a part of the opening of the communication hole 56f begins to open (see the balloon display in FIG. 4). At this time, the main valve 50 is not yet closed.

[0049] In the maximum energized state when the solenoid 80 is energized, the main sub-valve element 51 moves further to the left in the axial direction as shown in Fig. 5. As a result, the main sub-valve element 51 moves to the closed position, and the axial left end face 51a of the main sub-valve element 51 abuts against the main valve seat 10a, and the main valve 50 is fully closed. When the main sub-valve element 51 is in the closed position, the axial left end 56h of the CS valve element 56 moves to a position close to the axial right end face 11a of the partition adjustment member 11. That is, the CS valve element 56 is at the maximum stroke position in the most open direction, and the communication hole 56f is fully opened. At this time, approximately half of the opening of the communication hole 56f is blocked by the sealing portion Sa of the CS valve 57 (see the balloon display portion in Fig. 5).

[0050] Next, the operation of the displacement control valve V will be described in the order of the maximum current supply state (at start-up), when not energized, and during normal control.

[0051] First, the maximum energization state (at start-up) during energization will be described. After the variable displacement compressor M has been left unused for a long time, the variable displacement compressor M is started and the solenoid 80 in the displacement control valve V is energized, whereby the main valve 50 in the displacement control valve V is fully closed and the sub-valve 55 is fully opened. At this time, as shown in FIG. 5, the main and sub-valve body 51 strokes to the valve-closed position, so that the pressure-sensitive valve member 52, the abutment member 54, and the CS valve body 56 move together axially leftward. Then, the axial left end 56h of the CS valve body 56 approaches the axial right end face 11a of the partition adjustment member 11, and the communication hole 56f is fully opened. As a result, the Pc port 14 and the second Ps port 15 are in communication with each other, and the liquefied fluid in the control chamber 4 is discharged into the suction chamber 3 through the communication hole 56f in a short time. Therefore, the displacement control valve V can improve the responsiveness of the variable displacement compressor M at start-up. Moreover, when the main valve 50 is fully closed, the CS valve 57 fully opens the communication hole 56f, so that the flow rate of the fluid discharged through the communication hole 56f is maximized. In this way, the displacement control valve V can further improve the responsiveness of the variable displacement compressor M at the time of startup. Furthermore, since the suction pressure Ps in the intermediate communication passage 59 is high, the pressure sensitive valve 53 is opened as described above. This allows the displacement control valve V to quickly release the control pressure Pc to the second valve chamber 30 through the intermediate communication passage 59 and the communication hole 83a of the drive rod 83. In this way, the displacement control valve V, which uses the two flow paths opened by the CS valve 57 and the pressure sensitive valve 53 to discharge the liquefied fluid from the control chamber 4 into the suction chamber 3 in a short time, can improve the responsiveness of the variable displacement compressor M at the time of startup.

[0052] Furthermore, even when the control chamber 4 is at maximum capacity, the capacity control valve V of this embodiment closes the main valve 50 and opens the communication hole 56f by the CS valve 57 to communicate the Pc port 14 with the second Ps port 15. This allows the capacity control valve V of this embodiment to maintain the control pressure Pc and the suction pressure Ps at equal pressure (same pressure). Therefore, the stroke of the piston 7 in the cylinder 4a of the control chamber 4 is stable. Therefore, the capacity control valve V maintains the control chamber 4 at maximum capacity, and can improve the operating efficiency of the variable displacement compressor M.

[0053] Next, the non-energized state will be described. When the current is not being applied, as shown in FIG. 3, the main / sub-valve body 51, the pressure-sensitive valve member 52, and the contact member 54 are pushed axially rightward by the biasing force of the pressure-sensitive body 61. Therefore, the main valve 50 is fully opened. At the same time, the CS valve body 56, to which the biasing force of the coil spring 91 acts in the axially rightward direction, which is the valve closing direction, is in the valve closing position. Accordingly, the communication hole 56f is fully closed by the sealing portion Sa of the CS valve 57. According to these, the communication hole 56f is blocked by the sealing portion Sa of the CS valve 57. That is, the control fluid passing through the Pc port 14 does not flow into the second Ps port 15. Therefore, the controllability of the variable displacement compressor M is high when the variable displacement compressor M is stopped and then restarted a short time later, and the operation efficiency of the displacement control valve V is high.

[0054] Next, normal control will be described. During normal control, the opening degree and opening time of the main valve 50 are adjusted by the duty control of the capacity control valve V. As a result, the capacity control valve V controls the flow rate of fluid from the Pd port 12 to the Pc port 14. Even when the main valve 50 is slightly opened in the duty control of the capacity control valve V, the main sub-valve body 51 strokes toward the open valve position side from the stroke position P (see FIG. 6). As a result, a biasing force is applied from the coil spring 91 to the CS valve body 56 in the axial rightward direction, which is the valve closing direction. The sealing portion Sa of the CS valve 57 maintains the communication hole 56f in a fully closed state. As a result, during the stroke from the open valve position of the main sub-valve body 51 to the stroke position P, leakage of fluid from the Pc port 14 to the second Ps port 15 through the communication hole 56f is prevented. Therefore, the capacity control valve V can improve the control accuracy of the control pressure Pc in the variable displacement compressor M.

[0055] Furthermore, when the main sub-valve element 51 moves to stroke position P (see FIG. 6), the axial left end of the communication hole 56f in the CS valve element 56, which moves together with the main sub-valve element 51, radially overlaps with the axial right end of the annular groove 10d. Then, as the main sub-valve element 51 moves further until the main valve 50 is fully closed, the main valve 50 is gradually closed and the communication hole 56f is gradually opened by the CS valve 57. This makes it possible to set a region in which both the main valve 50 and the CS valve 57 (i.e., the communication hole 56f) are open between the stroke position P and the closed position of the main sub-valve element 51. The balance of the opening areas of the main valve 50 and the communication hole 56f can be adjusted according to the stroke position of the main sub-valve element 51.

[0056] The main valve 50 has a so-called poppet valve structure in which the opening area increases and decreases proportionally according to the stroke position of the main and sub-valve body 51. The CS valve 57 has a sealing portion Sa where the outer peripheral surface 56a of the CS valve body 56, which moves together with the main and sub-valve body 51 according to the stroke position of the main and sub-valve body 51, is in sliding contact with the guide surface 10e. Thus, unlike the main valve 50, the CS valve 57 has a spool valve structure, and the opening area of ​​the communication hole 56f provided in the CS valve body 56 increases and decreases. Therefore, as shown in FIG. 6, when the communication hole 56f starts to open from the fully closed state, the opening degree increases approximately exponentially. It is preferable that the opening degree of the communication hole 56f is not limited to approximately exponential, and that the increase rate of the opening degree of the communication hole 56f with respect to the stroke of the main and sub-valve body 51 is larger before the full opening immediately before the full opening state than when the communication hole 56f starts to open immediately after the fully closed state by the CS valve 57 (see FIG. 6). That is, during normal control when the main sub-valve element 51 strokes near the stroke position P (see FIG. 6), the CS valve 57 can suppress the increase rate of the opening of the communication hole 56f relative to the stroke of the main sub-valve element 51 to be small. Therefore, the CS valve 57 during normal control can reduce the leakage of fluid from the Pc port 14 to the second Ps port 15 through the communication hole 56f. This allows the capacity control valve V to improve the responsiveness of the control to reduce the control pressure Pc in the variable displacement compressor M. Furthermore, when the main valve 50 is fully closed, the CS valve 57 fully opens the communication hole 56f. This maximizes the flow rate of the fluid discharged through the communication hole 56f. Therefore, when the liquid refrigerant is discharged from the control chamber 4 at the start-up or when the control chamber 4 is at its maximum capacity during normal control, the capacity control valve V can quickly reduce the control pressure Pc. Note that the CS valve 57 does not have to be fully opened when the main valve 50 is fully closed.

[0057] The opening shape of the communication hole 56f is formed by a circle. Therefore, the opening degree of the communication hole 56f gradually increases in a gentle curve according to the stroke of the main / sub-valve body 51 (see FIG. 6). This reduces the leakage of fluid during normal control. In addition, the opening area of ​​the communication hole 56f quickly decreases from the fully open state.

[0058] In addition, the stroke position P (see FIG. 6) is adjusted by changing the formation position of the communication hole 56f in the axial direction of the CS valve body 56. In addition, the increase rate of the opening degree and the maximum opening area of ​​the communication hole 56f according to the stroke of the main / sub-valve body 51 are appropriately adjusted by changing the shape and size of the communication hole 56f.

[0059] 5, in this embodiment, when the communication hole 56f is fully opened by the CS valve 57, the opening of the communication hole 56f formed by a circle is only half-opened. This makes it difficult for the control of the capacity control valve V to be affected by the accuracy of the stroke of the main and sub-valve bodies 51.

[0060] In the capacity control valve V, the main and sub-valve element 51 constituting the main valve 50 and the CS valve element 56 constituting the CS valve 57 are constructed as separate separable members. This allows the main and sub-valve element 51 and the CS valve element 56 to have independent axial centers, thereby minimizing the influence on each other's operations. As a result, the openings of the main valve 50 and the CS valve 57 can be adjusted with high precision.

[0061] In addition, the CS valve element 56 abuts only in the axial direction against the axial left end surface 54a of the abutment member 54. This reduces the influence of the tilt or misalignment of the axial centers of the main / sub-valve element 51 and the CS valve element 56 on their respective operations.

[0062] In addition, the CS valve element 56 is biased by the coil spring 91 toward the axial right, which is the closing direction of the CS valve 57. Therefore, when the main valve 50 is opened, the CS valve element 56 follows the main / sub-valve element 51, the pressure-sensitive valve member 52, and the abutment member 54. This ensures that the CS valve 57 is closed.

[0063] The CS valve body 56 has a generally cylindrical shape. An annular step portion 10f is formed on the inner periphery of the valve housing 10. A part of the annular step portion 10f constitutes a guide surface 10e with which the outer circumferential surface 56a of the CS valve body 56 slides. Therefore, the capacity control valve V having the CS valve 57 has a simple structure.

[0064] Furthermore, when the solenoid 80 is in a maximum energized state and the communication hole 56f is fully opened by the CS valve 57, the axial left end face 51a of the main / sub-valve body 51 abuts against the main valve seat 10a, and the main valve 50 is fully closed. This determines the maximum opening area of ​​the communication hole 56f. Therefore, the capacity control valve V having the CS valve 57 has a simple structure.

[0065] In the capacity control valve V, the CS valve body 56 and the coil spring 91 are inserted into the pressure sensing chamber 40 from the axial left side of the valve housing 10, and then the partition adjustment member 11 is press-fitted and fixed into the axial left end of the valve housing 10. With this structure, the capacity control valve V is easy to assemble.

[0066] Furthermore, the Pc port 14 is disposed at a position closer to the Pd port 12 than the second Ps port 15. Therefore, in the displacement control valve V, the discharge pressure Pd can be easily transmitted to the control chamber 4 during normal control.

[0067] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0068] For example, in the above embodiment, the main and sub-valve element 51, the pressure-sensitive valve member 52, the abutment member 54, and the CS valve element 56 are configured separately, but the present invention is not limited to this, and the main and sub-valve element 51 and the pressure-sensitive valve member 52 may be configured integrally, and the abutment member 54 and the CS valve element 56 may be configured integrally. Also, the main and sub-valve element 51, the pressure-sensitive valve member 52, the abutment member 54, and the CS valve element 56 may all be configured integrally.

[0069] Furthermore, the communication passage and the fixed orifice that directly communicate between the control chamber 4 and the suction chamber 3 in the variable displacement compressor M may not be provided.

[0070] In the above embodiment, the sub-valve may not be provided. Also, the right axial end of the main / sub-valve body only needs to function as a support member for receiving the axial load, and does not necessarily need to have a sealing function.

[0071] Furthermore, the coil spring 91 as a spring is not limited to a compression spring, but may be a tension spring, and may have a shape other than a coil shape.

[0072] Furthermore, the pressure sensing body 61 may not have a coil spring inside. [Explanation of symbols]

[0073] 1 Casing 2 Discharge chamber 3 Suction chamber 4. Control Room 10 Valve housing 10a Main valve seat 10b Guide surface 10c Inner surface 10d groove 10e Guide surface 10f Annular step 11 Partition adjustment material 11a Right end surface in axial direction 11b Recess 12 Pd port (discharge port) 13 1st Ps port (suction port) 14 Pc port (control port) 15 2nd Ps port (suction port) 20 1st valve chamber 30 2nd valve chamber 40 Pressure Sensing Room 50 Main valve 51 Main and sub valve body (main valve body) 51a Axial left end 51b Axial right end 52 Pressure-sensitive valve member 52a Pressure sensitive valve seat 52b Cylindrical part 52c Flange 52d Second cylindrical section 52e Contact part 53 Pressure-sensitive valve 54 Contact member 55 Assistant Prosecutor 56 CS valve body 56a Outer surface 56b base 56c Recess 56d Extension 56e Protrusion 56f communication hole 56g Concave 56h Axial left end 57 CS valve 59 Intermediate connecting passage 60 space 61 Pressure sensor 62 Bellows core 63 Coil spring 70 Cap 70a sealing surface 80 Solenoid 82 Fixed core 82a Vice valve seat 91 Coil spring Pc Control pressure Pd Discharge pressure Ps Intake pressure Sa,Sb Sealed part V Capacity Control Valve

Claims

1. a valve housing having a discharge port through which a discharge fluid having a discharge pressure passes, a suction port through which a suction fluid having a suction pressure passes, and a control port through which a control fluid having a control pressure passes; A capacity control valve including: a main valve including a main valve element driven by a solenoid; and a main valve seat provided between the discharge port and the control port and contactable by the main valve element, a CS valve having a CS valve element formed with a radially penetrating communication hole and sliding in the valve housing in conjunction with the main valve element, the communication hole enabling communication between the control port and the suction port depending on a sliding position of the CS valve element, A capacity control valve in which the opening area of ​​the communication hole changes depending on the slide position of the CS valve body.

2. 2. The displacement control valve according to claim 1, wherein the CS valve body is formed as a separate member that is separable from the main valve body.

3. 3. The displacement control valve according to claim 2, wherein the main valve body and the CS valve body are capable of contacting each other only in the axial direction.

4. 4. The displacement control valve according to claim 2, wherein the CS valve element is biased in a closing direction by a spring.

5. 5. The displacement control valve according to claim 1, wherein the opening shape of the communication hole is formed from a part of a circle.

6. 5. The displacement control valve according to claim 1, wherein the opening shape of the communication hole is circular.

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