Capacity control valve

Abstract

The present invention provides a capacity control valve having a fluid discharge function at startup and high operating efficiency. A capacity control valve (V) comprises: a valve housing (10); a main valve (50) which is composed of a valve core (51) driven by a solenoid (80) and a main valve seat (10a) provided between a discharge port (12) and a control port (14) and capable of being contacted by the valve core (51); and a pressure-sensitive valve component (52) which, together with a pressure-sensitive body (60) arranged in a pressure-sensitive chamber (40), constitutes a pressure-sensitive valve (53) which can discharge fluid by opening and closing the pressure-sensitive valve (53). The intermediate connecting passage (55) connects the control port (14) with the suction port (13), wherein a through hole (52d) connected to the intermediate connecting passage (55) is formed on the pressure-sensitive valve component (52), and a sliding valve core (90) is provided. The sliding valve core slides relative to the pressure-sensitive valve component (52) to open and close the through hole (52d), and a force applying unit (91) is provided on the outer diameter side of the sliding valve core (90) to apply force to the sliding valve core (90) in the opening direction.

Description

Technical Field

[0001] The present invention relates to a capacity control valve for variably controlling the capacity of a working fluid, and for example, to a capacity control valve for controlling the discharge volume of a variable capacity compressor used in an automobile air conditioning system according to pressure. Background Art

[0002] Variable capacity compressors used in air conditioning systems in automobiles and other applications consist of a rotating shaft driven by the engine, a swash plate connected to the rotating shaft at a variable inclination angle, and a compression piston connected to the swash plate. By varying the inclination angle of the swash plate, the piston stroke is varied, thereby controlling the amount of fluid discharged. Using a capacity control valve driven open and closed by electromagnetic force, the pressure in the control chamber, Pc, is controlled by appropriately controlling the pressure in the control chamber, utilizing the suction pressure Ps in the suction chamber that draws in fluid, the discharge pressure Pd in the discharge chamber that discharges fluid pressurized by the piston, and the control pressure Pc in the control chamber that houses the swash plate. This allows the swash plate's inclination angle to be continuously varied.

[0003] During continuous operation of the variable capacity compressor, the capacity control valve is normally controlled as follows: The control computer controls power supply, and the electromagnetic force generated by the solenoid causes the valve core to move axially. This opens and closes the main valve between the discharge port, through which a discharge fluid having a discharge pressure Pd passes, and the control port, through which a control fluid having a control pressure Pc passes, thereby adjusting the control pressure Pc in the control chamber of the variable capacity compressor.

[0004] During normal operation, the capacity control valve appropriately controls the pressure in the control chamber of the variable capacity compressor. By continuously changing the swash plate's inclination angle relative to the rotational axis, the piston's stroke is varied, controlling the amount of fluid discharged from the discharge chamber and adjusting the air conditioning system to the target cooling capacity. Furthermore, when operating the variable capacity compressor at maximum capacity, the capacity control valve's main valve is closed to reduce the pressure in the control chamber, thereby maximizing the swash plate's inclination angle.

[0005] Furthermore, a capacity control valve is also known that includes an auxiliary communication passage connecting a control port and a suction port of the capacity control valve. During startup, refrigerant in a control chamber of a variable capacity compressor is discharged through the control port, the auxiliary communication passage, and the suction port into the suction chamber of the variable capacity compressor. This allows the pressure in the control chamber to be rapidly reduced during startup, thereby improving the responsiveness of the variable capacity compressor (see Patent Document 1).

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent No. 5167121 (page 7,Figure 2 ) Summary of the Invention

[0009] Problems to be solved by the invention

[0010] However, in Patent Document 1, although the fluid discharge function is excellent at startup, when the variable capacity compressor is continuously driven, the auxiliary communication path is connected, and the refrigerant flows from the control port into the suction port, so the refrigerant circulation volume is large, and the operating efficiency of the variable capacity compressor may decrease.

[0011] The present invention has been made in view of such problems, and an object of the present invention is to provide a displacement control valve having a fluid discharge function at startup and high operating efficiency.

[0012] Means for solving problems

[0013] In order to solve the above problems, the capacity control valve of the present invention has:

[0014] a valve housing formed with a discharge port for passage of a discharge fluid having a discharge pressure, a suction port for passage of a suction fluid having a suction pressure, and a control port for passage of a control fluid having a control pressure;

[0015] a main valve composed of a valve core driven by a solenoid and a main valve seat provided between the discharge port and the control port and capable of being contacted by the valve core;

[0016] a pressure-sensitive body disposed in the pressure-sensitive chamber; and

[0017] a pressure-sensitive valve component extending from the valve core toward the pressure-sensitive chamber and constituting a pressure-sensitive valve together with the pressure-sensitive body;

[0018] An intermediate communication passage is formed on the valve core and the pressure-sensitive valve member. The control port and the suction port can be communicated through the intermediate communication passage by opening and closing the pressure-sensitive valve.

[0019] The pressure-sensitive valve member is provided with a through hole communicating with the intermediate communication path, and a sliding valve core is provided. The sliding valve core slides relative to the pressure-sensitive valve member to open and close the through hole.

[0020] An urging unit for urging the sliding valve element in an opening direction is provided on an outer diameter side of the sliding valve element.

[0021] As a result, during startup and when the main valve is closed in the maximum energized state, the force of the force-applying unit reliably slides the sliding valve core, opening the through-hole and connecting the control port with the suction port, thereby rapidly reducing the control pressure. Meanwhile, when the main valve is controlled in the energized state, the fluid flowing due to the opening of the main valve causes the sliding valve core to slide, closing the through-hole and isolating the control port from the suction port. This prevents fluid from flowing from the control port to the suction port. This improves the discharge of liquid refrigerant during startup of the variable capacity compressor and improves its operating efficiency.

[0022] The urging means may be arranged between the sliding valve element and a support portion formed on a front end side of the through hole of the pressure sensitive valve member.

[0023] Thus, the biasing unit and the through hole of the pressure-sensitive valve member can be arranged at radially overlapping positions, thereby shortening the axial lengths of the sliding valve element and the pressure-sensitive valve member, respectively, and achieving a compact capacity control valve.

[0024] The urging unit may be arranged in a state of being exposed to the pressure sensitive chamber.

[0025] Thus, the influence of the pressure of the fluid accompanying the opening and closing of the through-hole by the sliding valve element is less likely to act on the urging unit, and thus the responsiveness of the urging unit is improved.

[0026] The inner peripheral surface of the sliding valve element may be formed in the same plane.

[0027] In this way, the sliding performance of the sliding valve core relative to the pressure-sensitive valve component can be improved, and the amount of fluid leaking into the intermediate connecting path through the small gap between the inner peripheral surface of the sliding valve core and the outer peripheral surface of the pressure-sensitive valve component can be reduced, thereby further improving the operating efficiency of the variable capacity compressor.

[0028] The sliding valve element may be formed with a receiving surface facing the main valve.

[0029] Thus, the sliding valve element is easily operated by the fluid flowing due to the opening of the main valve.

[0030] Alternatively, the receiving surface may be inclined relative to the reciprocating direction of the valve core.

[0031] Thus, the fluid easily flows from the discharge port toward the control port due to the opening of the main valve.

[0032] The sliding valve element may be arranged so as to be capable of performing a stroke in a state where the through hole is closed.

[0033] As a result, the through hole remains closed until the sliding valve core slides a predetermined distance or more. Therefore, even if the sliding valve core slightly slides due to disturbances such as vibration, the through hole remains closed. This provides the capacity control valve with strong resistance to disturbances and excellent control accuracy.

[0034] The valve element and the pressure-sensitive valve member may be separate bodies, and a stopper for restricting movement of the sliding valve element toward the main valve may be formed on the valve element.

[0035] Thus, the sliding of the sliding valve element can be restricted with a simple structure.

[0036] Alternatively, a plurality of through holes may be formed in the pressure-sensitive valve member.

[0037] This ensures a wide flow path cross-sectional area. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 1. It is a schematic structural diagram showing a swash plate type variable displacement compressor incorporating a displacement control valve according to an embodiment of the present invention;

[0039] Figure 2 This is a cross-sectional view showing a state in which the main valve is open and the through hole of the pressure-sensitive valve member is closed by the sliding valve element in the non-energized state of the capacity control valve of the embodiment;

[0040] Figure 3 This figure shows a case where the main valve is open and the through hole of the pressure sensitive valve member is closed by the sliding valve element in the non-energized state of the capacity control valve of the embodiment. Figure 2 An enlarged cross-sectional view of

[0041] Figure 4 This is an enlarged cross-sectional view showing a state in which the main valve is closed and the through hole of the pressure-sensitive valve member is opened by the movement of the sliding valve element in the capacity control valve of the embodiment in an energized state;

[0042] Figure 5 This is an enlarged cross-sectional view showing a modified example of the capacity control valve of the embodiment. DETAILED DESCRIPTION

[0043] Hereinafter, modes for implementing the capacity control valve of the present invention will be described based on embodiments.

[0044] [Example]

[0045] Reference Figures 1 to 4 The capacity control valve of the embodiment will be described. Figure 2Specifically, the left side of the paper where the pressure sensitive body 60 is arranged is the left side of the capacity control valve, and the right side of the paper where the solenoid 80 is arranged is the right side of the capacity control valve.

[0046] The capacity control valve V of the present invention is assembled into a variable capacity compressor M used in the air conditioning system of an automobile, etc., and variably controls the pressure of the refrigerant, i.e., the working fluid (hereinafter referred to as "fluid"), thereby controlling the discharge volume of the variable capacity compressor M and adjusting the air conditioning system to the target cooling capacity.

[0047] First, the variable capacity compressor M will be described. Figure 1 As shown, a variable capacity compressor M includes a housing 1 having a discharge chamber 2, a suction chamber 3, a control chamber 4, and a plurality of cylinders 4a. Furthermore, a communication passage (not shown) is provided in the variable capacity compressor M, directly connecting the control chamber 4 and the suction chamber 3. A fixed orifice is provided in this communication passage for balancing the pressures in the suction chamber 3 and the control chamber 4.

[0048] In addition, the variable capacity compressor M comprises: a rotating shaft 5, which is rotationally driven by an unillustrated engine provided on the outside of the housing 1; a swash plate 6, which is tiltably connected to the rotating shaft 5 via a hinge mechanism 8 in the control chamber 4; and a plurality of pistons 7, which are connected to the swash plate 6 and are freely reciprocatingly engaged in each cylinder 4a, wherein a capacity control valve V driven to open and close by electromagnetic force is used, and the pressure in the control chamber 4 is appropriately controlled by utilizing the suction pressure Ps of the suction chamber 3 for sucking in the fluid, the discharge pressure Pd of the discharge chamber 2 for discharging the fluid pressurized by the piston 7, and the control pressure Pc of the control chamber 4 that accommodates the swash plate 6, so that the inclination angle of the swash plate 6 is continuously changed, thereby changing the stroke amount of the piston 7 to control the discharge amount of the fluid. In addition, for the sake of convenience, in Figure 1 In FIG, the capacity control valve V incorporated in the variable capacity compressor M is omitted from illustration.

[0049] Specifically, as the control pressure Pc within the control chamber 4 increases, the tilt angle of the swash plate 6 relative to the rotating shaft 5 decreases, reducing the stroke of the piston 7. However, when the pressure reaches a certain level or above, the swash plate 6 becomes approximately perpendicular to the rotating shaft 5, that is, slightly tilted from perpendicular. At this point, the stroke of the piston 7 is minimized, and the pressure applied by the piston 7 to the fluid within the cylinder 4a is minimized. As a result, the amount of fluid discharged into the discharge chamber 2 decreases, minimizing the cooling capacity of the air conditioning system. On the other hand, as the control pressure Pc within the control chamber 4 decreases, the tilt angle of the swash plate 6 relative to the rotating shaft 5 increases, increasing the stroke of the piston 7. However, when the pressure reaches a certain level or below, the tilt angle of the swash plate 6 relative to the rotating shaft 5 reaches its maximum. At this point, the stroke of the piston 7 is maximized, and the pressure applied by the piston 7 to the fluid within the cylinder 4a is maximized. As a result, the amount of fluid discharged into the discharge chamber 2 increases, maximizing the cooling capacity of the air conditioning system.

[0050] like Figure 2 As shown, the capacity control valve V assembled in the variable capacity compressor M adjusts the current supplied to the coil 86 constituting the solenoid 80 to control the opening and closing of the main valve 50 and the sub-valve 54 in the capacity control valve V. The pressure sensitive valve 53 is also controlled to open and close according to the suction pressure Ps, thereby controlling the fluid flowing into or out of the control chamber 4, thereby variably controlling the control pressure Pc in the control chamber 4.

[0051] In this embodiment, the main valve 50 comprises a main and sub-spool 51 serving as the valve element, and a main valve seat 10a formed on an annular projection 10c, which projects radially inward from the inner circumference of the valve housing 10 and has an isosceles trapezoidal cross-section. The main valve 50 is opened and closed by the axially left end 51a of the main and sub-spool 51 contacting or separating from the main valve seat 10a. The sub-valve 54 comprises the main and sub-spool 51 and a sub-valve seat 82a formed on the open end surface of the fixed core 82, i.e., the axially left end surface of the fixed core 82. The sub-valve 54 is opened and closed by the axially right step 51b of the main and sub-spool 51 contacting or separating from the sub-valve seat 82a. The pressure-sensitive valve 53 comprises an adapter 70 of the pressure-sensitive body 60 and a pressure-sensitive valve seat 52a formed at the axially left end of the pressure-sensitive valve member 52. The pressure-sensitive valve 53 is opened and closed by the axially right end 70a of the adapter 70 contacting or separating from the pressure-sensitive valve seat 52a.

[0052] Next, the structure of the capacity control valve V will be described. Figure 2As shown, the capacity control valve V is mainly composed of the following parts: a valve housing 10, which is formed of a metal material or a resin material; a main and auxiliary valve cores 51 and a pressure-sensitive valve component 52, which are arranged in the valve housing 10 so as to be able to move back and forth axially freely; a pressure-sensitive body 60, which applies an axial rightward force to the main and auxiliary valve cores 51 and the pressure-sensitive valve component 52 according to the suction pressure Ps; a solenoid 80, which is connected to the valve housing 10 and applies a driving force to the main and auxiliary valve cores 51 and the pressure-sensitive valve component 52; and a sliding valve core 90, which is configured to be able to move back and forth axially relative to the pressure-sensitive valve component 52 through the flow of fluid generated by the opening of the main valve 50. The sliding valve core 90 opens and closes the flow path between the auxiliary valve chamber 30, which becomes the suction pressure Ps, and the pressure sensitive chamber 40, which becomes the control pressure Pc, through its reciprocating movement. Therefore, it can also be said that it, together with the pressure sensitive valve component 52, constitutes a CS valve that quickly releases the control pressure Pc of the control chamber 4 to the suction chamber 3 through the through hole 52d and the intermediate connecting path 55 of the pressure sensitive valve component 52 described later.

[0053] like Figure 2 As shown, the solenoid 80 is mainly composed of the following parts: a shell 81, which has an opening portion 81a opened axially to the left; a roughly cylindrical fixed iron core 82, which is inserted into the opening portion 81a of the shell 81 from the axial left and fixed to the inner diameter side of the shell 81; a drive rod 83, which can move back and forth axially on the inner diameter side of the fixed iron core 82, and its axial left end is connected and fixed to the main and auxiliary valve cores 51; a movable iron core 84, which is fixed to the axial right end of the drive rod 83; a coil spring 85, which is arranged between the fixed iron core 82 and the movable iron core 84 to apply force to the movable iron core 84 axially to the right; and an excitation coil 86, which is wound on the outside of the fixed iron core 82 via a winding frame.

[0054] The housing 81 has a recessed portion 81 b formed at the inner diameter side of the axial left end thereof, which is recessed axially rightward. The axial right end portion of the valve housing 10 is fitted and fixed to the recessed portion 81 b in a substantially sealed manner.

[0055] The fixed iron core 82 is formed of a rigid body of magnetic material such as iron and silicon steel, and comprises: a cylindrical portion 82b, which is formed with an insertion hole 82c extending axially and for the drive rod 83 to be inserted; and an annular flange portion 82d, which extends in the outer diameter direction from the outer peripheral surface of the axial left end portion of the cylindrical portion 82b, and is formed with a recessed portion 82e on the inner diameter side of the axial left end of the cylindrical portion 82b that is recessed axially to the right.

[0056] like Figure 2As shown, the valve housing 10 is provided with: a Pd port 12 serving as a discharge port, which is connected to the discharge chamber 2 of the variable capacity compressor M; a Ps port 13 serving as a suction port, which is connected to the suction chamber 3 of the variable capacity compressor M; and a Pc port 14 serving as a control port, which is connected to the control chamber 4 of the variable capacity compressor M.

[0057] The valve housing 10 has a bottomed, substantially cylindrical shape by press-fitting a separation adjustment member 11 into a substantially sealed state at its axial left end.

[0058] Formed inside the valve housing 10 are: a main valve chamber 20, which is connected to the Pd port 12 and is configured with the axial left end 51a side of the main and auxiliary valve cores 51; an auxiliary valve chamber 30, which is connected to the Ps port 13 and is configured with the back pressure side of the main and auxiliary valve cores 51, that is, the step portion 51b on the axial right side of the main and auxiliary valve cores 51; and a pressure-sensitive chamber 40, which is connected to the Pc port 14 and is configured with a pressure-sensitive valve component 52, a sliding valve core 90 and a pressure-sensitive body 60.

[0059] Furthermore, within the valve housing 10, a main and sub-spools 51 and a pressure-sensitive valve member 52 are arranged for free axial reciprocation. A small-diameter guide hole 10b is formed at the right axial end of the inner circumference of the valve housing 10, allowing the outer circumferences of the main and sub-spools 51 to slide in substantially sealed contact. Furthermore, within the valve housing 10, the main valve chamber 20 and the sub-valve chamber 30 are separated by the outer circumferences of the main and sub-spools 51 and the inner circumference of the guide hole 10b. Furthermore, a slight radial separation creates a small gap between the inner circumference of the guide hole 10b and the outer circumferences of the main and sub-spools 51, enabling smooth axial movement of the main and sub-spools 51 relative to the valve housing 10.

[0060] like Figure 2 As shown, the pressure sensitive body 60 mainly comprises a bellows core 61 having a coil spring 62 built therein and an adapter 70 provided at the axial right end of the bellows core 61 . The axial left end of the bellows core 61 is fixed to the separation adjustment member 11 .

[0061] Furthermore, the pressure-sensitive body 60 is disposed within the pressure-sensitive chamber 40. The adaptor 70 is biased axially rightward by the force generated by the coil spring 62 and the bellows core 61, causing the axially right end 70a of the adaptor 70 to seat on the pressure-sensitive valve seat 52a of the pressure-sensitive valve member 52. Furthermore, the adaptor 70 is biased axially leftward by the suction pressure Ps in the intermediate communication passage 55.

[0062] like Figure 2As shown, the main and sub-valve cores 51 are constructed in a roughly cylindrical shape, and an independent pressure-sensitive valve component 52, which is constructed in a cylindrical shape with a flange and has a roughly turret shape when viewed from the side, is inserted and fixed in a roughly sealed manner on its axial left end portion, and a drive rod 83 is inserted and fixed in a roughly sealed manner on its axial right end portion, and they can move axially together.

[0063] In addition, the labyrinth effect of the annular groove formed on the outer peripheral surface of the main and auxiliary valve cores 51 can suppress the leakage of fluid from the main valve chamber 20 to the auxiliary valve chamber 30, thereby maintaining the discharge pressure Pd of the discharge fluid supplied from the discharge chamber 2 to the main valve chamber 20 via the Pd port 12.

[0064] An intermediate communication passage 55 is formed within the main and auxiliary valve cores 51 and the pressure-sensitive valve member 52, extending entirely axially through a connecting hollow hole. The intermediate communication passage 55 communicates with the auxiliary valve chamber 30 via a plurality of through holes 51c extending radially through the axial right end portions of the main and auxiliary valve cores 51.

[0065] like Figures 2 to 4 As shown, the pressure-sensitive valve member 52 is cylindrical with a flange, and has a roughly turret-like shape when viewed from the side. It comprises a cylindrical base portion 52b, the axial right end of which is inserted and fixed to the main and auxiliary valve elements 51 in a substantially sealing manner and externally fitted with the sliding valve element 90. A flange portion 52c, serving as a support portion, extends radially from the outer circumference of the axial left end of the base portion 52b and forms a pressure-sensitive valve seat 52a that contacts and separates from the axial right end 70a of the adapter 70. Furthermore, a plurality of through-holes 52d are provided radially through the axial left end of the base portion 52b and communicate with the intermediate communication passage 55.

[0066] like Figures 2 to 4 As shown, the sliding valve core 90 is constructed as a cylindrical shape with a flange, and has: a cylindrical base 90a, which is embedded in the base 52b of the pressure-sensitive valve component 52; and a flange portion 90b, which extends from the outer peripheral surface of the axially approximately central portion of the base 90a in the outer diameter direction, and the sliding valve core 90 is urged toward the axial right by a coil spring 91 as a force-applying unit arranged on the outer diameter side of the sliding valve core 90.

[0067] The side surface on the axial right side of the flange portion 90b serves as a receiving surface 90c, which faces the axial right side of the main valve 50 and is inclined relative to the reciprocating movement direction of the main and auxiliary valve cores 51 and the sliding valve core 90. In addition, the receiving surface 90c is described as being inclined in a straight line in side view, but is not limited to this. For example, it can also be curved in side view.

[0068] The inner side of the sliding valve core 90, that is, the inner circumferential surface of the base portion 90a, is formed into a flat surface. Furthermore, a slight radial separation forms a small gap between the inner circumferential surface of the base portion 90a and the outer circumferential surface of the base portion 52b of the pressure-sensitive valve member 52, allowing the sliding valve core 90 to move smoothly relative to the pressure-sensitive valve member 52 in the axial direction.

[0069] Furthermore, an end surface portion 90d is formed at the axial right end of the sliding valve element 90, that is, the axial right end of the base portion 90a, which opens when the through hole 52d of the pressure-sensitive valve member 52 is opened when the sliding valve element 90 moves axially rightward (see FIG. Figure 4 ), and contacts the stopper portion 51d formed on the inner diameter side of the axial left end of the main and auxiliary valve cores 51. In addition, an end surface portion 90e is formed at the axial left end of the sliding valve core 90, that is, the axial left end of the base portion 90a, which is closed when the through hole 52d of the pressure-sensitive valve member 52 is closed when the sliding valve core 90 moves axially to the left (refer to Figure 2 and Figure 3 ), and can abut against the axially right side surface 52e of the flange portion 52c of the pressure-sensitive valve member 52. Thus, the axial position of the sliding valve element 90 when the through hole 52d of the pressure-sensitive valve member 52 is opened or closed is determined by the axially left end portion of the base portion 90a of the sliding valve element 90.

[0070] In addition, the through hole 52d of the pressure-sensitive valve component 52 is formed at a position axially to the right of the side surface 52e on the axial right side of the flange portion 52c, and during the period when the end surface portion 90e formed at the axial left end of the base 90a of the sliding valve core 90 moves from a state of abutting against the side surface 52e of the flange portion 52c of the pressure-sensitive valve component 52 to an axial position of the open end on the axial left side of the through hole 52d, the axial left end portion of the base 90a of the sliding valve core 90 overlaps with the through hole 52d in the radial direction, maintaining the through hole 52d in a closed state.

[0071] like Figures 2 to 4 As shown, the axial left end of the coil spring 91 abuts against the axial right side surface 52e of the flange portion 52c of the pressure-sensitive valve component 52, and the axial right end of the coil spring 91 abuts against the axial left side surface 90f of the flange portion 90b of the sliding valve core 90 embedded on the base 52b of the pressure-sensitive valve component 52, applying force to the sliding valve core 90 axially to the right toward the stop portion 51d of the main and sub-valve cores 51.

[0072] The coil spring 91 is a compression spring, and its inner periphery is slightly separated in the radial direction from the outer periphery of the base 90a of the sliding valve element 90. The inner periphery of the coil spring 91 may also be guided by the outer periphery of the base 90a of the sliding valve element 90.

[0073] Next, the operation of the capacity control valve V, mainly the operation of the opening and closing mechanism of the through hole 52d of the pressure sensitive valve member 52 by the sliding valve element 90, will be described in the order of startup and normal control.

[0074] First, the startup process will be described. After the variable capacity compressor M has been left unused for a long period of time, the discharge pressure Pd, control pressure Pc, and suction pressure Ps are roughly balanced. Although not shown in the figure for ease of explanation, leaving the variable capacity compressor M in a stopped state for a long period of time may cause the high-pressure fluid in the control chamber 4 to liquefy. However, at this time, due to the high suction pressure Ps in the intermediate connecting passage 55, the pressure-sensitive body 60 contracts to separate the axial right end 70a of the adapter 70 from the pressure-sensitive valve seat 52a of the pressure-sensitive valve component 52, thereby opening the pressure-sensitive valve 53. Thus, for example, when the suction pressure Ps is high at startup, by opening the pressure-sensitive valve 53, the liquid refrigerant in the control chamber 4 can be discharged to the suction chamber 3 via the intermediate connecting passage 55 in a short period of time.

[0075] When the capacity control valve V is in the non-energized state, the movable iron core 84 is pressed axially to the right by the force of the coil spring 85 constituting the solenoid 80, the coil spring 62 constituting the pressure sensitive body 60, and the force of the bellows core 61. As a result, the driving rod 83, the main and auxiliary valve cores 51, and the pressure sensitive valve member 52 move axially to the right. The step portion 51b on the axial right side of the main and auxiliary valve cores 51 seats on the auxiliary valve seat 82a of the fixed iron core 82, the auxiliary valve 54 is closed, and the axial left end 51a of the main and auxiliary valve cores 51 separates from the main valve seat 10a formed on the inner peripheral surface of the valve housing 10, and the main valve 50 opens (see FIG. 1 ). Figure 2 At this time, the sliding valve element 90 is located in the axial left direction, and the through hole 52d of the pressure-sensitive valve member 52 is closed.

[0076] By starting the variable capacity compressor M and placing the capacity control valve V in an energized state, the electromagnetic force generated by applying current to the solenoid 80 pulls the movable iron core 84 toward the fixed iron core 82 axially to the left, and the drive rod 83 fixed to the movable iron core 84, the main and auxiliary valve cores 51, and the pressure-sensitive valve member 52 move axially to the left together, and the pressure-sensitive body 60 is pressed axially to the left and contracts, thereby separating the step portion 51b on the axial right side of the main and auxiliary valve cores 51 from the auxiliary valve seat 82a, thereby opening the auxiliary valve 54, and the axial left end 51a of the main and auxiliary valve cores 51 sits on the main valve seat 10a, and the main valve 50 is closed (refer to FIG. Figure 4 At this time, the sliding valve element 90 is reliably moved axially to the right by the biasing force of the coil spring 91, and the through hole 52d of the pressure-sensitive valve member 52 is opened.

[0077] Thus, at the time of starting, when the sliding valve core 90 opens the through hole 52d of the pressure sensitive valve member 52, the pressure sensitive chamber 40 communicates with the intermediate communication path 55 via the through hole 52d, and the fluid flows (at Figure 4 Indicated by a solid arrow in the figure). Specifically, the sliding valve element 90 opens the through hole 52d of the pressure-sensitive valve member 52, forming a flow path for discharging fluid in the order of the control chamber 4, the Pc port 14, the pressure-sensitive chamber 40, the through hole 52d, the intermediate communication passage 55, the auxiliary valve chamber 30, the Ps port 13, and the suction chamber 3. This allows for the rapid discharge of liquefied fluid from the control chamber 4, thereby improving startup responsiveness. Furthermore, even when the pressure-sensitive valve 53 is prevented from opening due to the suction pressure Ps, as described above, the sliding valve element 90 still opens the through hole 52d of the pressure-sensitive valve member 52, thereby forming a flow path for discharging fluid from the control chamber 4 to the suction chamber 3 via the intermediate communication passage 55.

[0078] Next, the normal control will be described. During normal control, the opening degree and opening time of the main valve 50 are adjusted by the duty cycle control of the capacity control valve V to control the flow rate of the fluid from the Pd port 12 to the Pc port 14. At this time, the sliding valve core 90 receives the flow of the fluid from the Pd port 12 to the Pc port 14 caused by the opening of the main valve 50 through the receiving surface 90c (at Figure 3 Indicated by a solid arrow in the figure), thereby exerting a force on the sliding valve core 90 to move axially to the left (in the figure). Figure 3 Indicated by a white arrow), the sliding valve core 90 overcomes the force of the coil spring 91 and moves axially to the left, closing the through hole 52d of the pressure-sensitive valve member 52 through the axial left end of the base 90a (refer to Figure 3 ).

[0079] In this way, during normal control, when the sliding valve core 90 closes the through hole 52d of the pressure-sensitive valve component 52, no flow path is formed to the control chamber 4, the Pc port 14, the pressure-sensitive chamber 40, the through hole 52d, the intermediate connecting path 55, the auxiliary valve chamber 30, the Ps port 13, and the suction chamber 3. Therefore, the outflow amount of refrigerant from the control chamber 4 to the suction chamber 3 is reduced, thereby improving the operating efficiency of the variable capacity compressor M.

[0080] Furthermore, when the variable capacity compressor M is driven at maximum capacity, the capacity control valve V is energized at its maximum duty cycle, closing the main valve 50. This allows the sliding valve element 90 to move axially rightward, opening the through hole 52d of the pressure-sensitive valve member 52 and connecting the Pc port 14 with the Ps port 13. This allows the control pressure Pc to be rapidly reduced. Consequently, the piston 7 within the cylinder 4a of the control chamber 4 can be rapidly displaced, maintaining the maximum capacity and improving operational efficiency.

[0081] In this way, during normal control of the capacity control valve V, the through hole 52d of the pressure-sensitive valve member 52 is closed, and during startup and maximum capacity operation, the sliding valve core 90 is moved to open the through hole 52d of the pressure-sensitive valve member 52, thereby improving the operating efficiency of the variable capacity compressor M.

[0082] In addition, the coil spring 91 is arranged between the side surface 90f on the axial left side of the flange portion 90b of the sliding valve core 90 and the side surface 52e on the axial right side of the flange portion 52c formed on the front end side, that is, the axial left side, of the through hole 52d of the pressure-sensitive valve component 52. The coil spring 91 and the through hole 52d of the pressure-sensitive valve component 52 can be arranged at a position where they overlap in the radial direction, thereby shortening the axial lengths of the sliding valve core 90 and the pressure-sensitive valve component 52 respectively, and the capacity control valve V can be compactly constructed.

[0083] Specifically, for example, Figure 5 As in the modified example of the capacity control valve V shown in FIG. 1 , the axial length of the flange portion 190 b of the sliding valve element 190 and the axial length of the base portion 152 b of the pressure-sensitive valve member 152 located axially to the right of the through hole 152 d can be shortened compared to the above-described embodiment. Consequently, the axial length of the valve housing 110 can be shortened, thereby enabling the capacity control valve V to be constructed in a compact manner.

[0084] In addition, the coil spring 91 is arranged in a state exposed in the pressure-sensitive chamber 40. The influence of the fluid pressure caused by the opening and closing of the through hole 52d of the pressure-sensitive valve component 52 by the reciprocating movement of the sliding valve core 90 is difficult to act on the coil spring 91, so the responsiveness of the coil spring 91 is good.

[0085] Furthermore, the inner circumferential surface of the sliding valve element 90 is formed to be flat, specifically, to be cylindrical with a constant inner diameter throughout the entire axial direction. This allows the sliding valve element 90 to slide over a relatively long axial range relative to the outer circumferential surface of the base portion 52b of the pressure-sensitive valve member 52, thereby improving the slidability of the sliding valve element 90 relative to the pressure-sensitive valve member 52. Furthermore, by making the radial dimension of the minute gap between the inner circumferential surface of the sliding valve element 90 and the outer circumferential surface of the base portion 52b of the pressure-sensitive valve member 52 substantially constant, the amount of fluid that leaks slightly into the intermediate communication passage 55 through this minute gap can be further reduced, thereby further improving the operating efficiency of the variable capacity compressor M.

[0086] In addition, the inner circumferential surface of the sliding valve core 90 is formed into the same plane, so that the pressure of the fluid entering the small gap between the inner circumferential surface of the sliding valve core 90 and the outer circumferential surface of the base 52b of the pressure-sensitive valve component 52 will not act in the axial direction. Therefore, even if a differential pressure occurs between the small gap and the pressure-sensitive chamber 40, the influence of the differential pressure can be suppressed and the sliding valve core 90 can move smoothly.

[0087] In addition, the outer peripheral surface of the sliding valve core 90 can slide in the entire axial direction relative to the outer peripheral surface of the base 52b of the pressure-sensitive valve component 52, thereby stabilizing the movement of the fluid that leaks slightly to the intermediate connecting path 55 through a small gap that is longer in the axial direction, and in particular, it is difficult to affect the opening action of the sliding valve core 90 on the through hole 52d caused by the force of the coil spring 91.

[0088] In addition, the through hole 52d of the pressure-sensitive valve component 52 is formed to penetrate the base 52b with a radially thinner thickness in the axial direction, thereby shortening the radial length of the through hole 52d, so that the fluid can easily flow from the pressure-sensitive chamber 40 into the intermediate connecting path 55 through the through hole 52d, thereby improving the responsiveness of the variable capacity compressor M.

[0089] In addition, since the receiving surface 90c of the sliding valve core 90 faces the axial right side where the main valve 50 is formed, when the capacity control valve V is not energized, it is easy to receive the flow of fluid from the Pd port 12 to the Pc port 14 generated by the opening of the main valve 50, thereby exerting a force on the sliding valve core 90 to move axially to the left, and the sliding valve core 90 is easy to operate.

[0090] In addition, the receiving surface 90c of the sliding valve core 90 is inclined relative to the reciprocating movement direction of the main and sub-valve cores 51 and the sliding valve core 90. Therefore, when the capacity control valve V is not powered, it is easy for the main valve 50 to open, causing the fluid to flow from the Pd port 12 to the Pc port 14.

[0091] Furthermore, in the valve housing 10, the sliding valve core 90 is configured so that the outer peripheral surface formed by the axial right end portion of the base 90a and the receiving surface 90c on the axial right side of the flange portion 90b approaches the inner peripheral surface of the annular protrusion 10c of the main valve seat 10a forming the main valve 50, thereby forming a flow path with a relatively narrow width between the main valve chamber 20 and the pressure sensitive chamber 40, so that it is easier to generate the flow of fluid from the Pd port 12 to the Pc port 14 due to the opening of the main valve 50.

[0092] In addition, a coil spring 91 is arranged on the back side of the receiving surface 90c of the sliding valve core 90, that is, on the axial left side of the flange portion 90b, which urges the sliding valve core 90 toward the axial right, so that the sliding valve core 90 can be moved axially reciprocatingly with a simple structure.

[0093] Furthermore, the sliding valve element 90 maintains the through hole 52d of the pressure-sensitive valve member 52 closed by the axially left end portion of the base portion 90a from the state where the axially left end surface portion 90e abuts the side surface 52e of the flange portion 52c of the pressure-sensitive valve member 52 until it slides axially rightward by a predetermined distance or more. Therefore, even if the sliding valve element 90 slightly slides due to disturbances such as vibration, the through hole 52d of the pressure-sensitive valve member 52 is maintained closed. Consequently, the capacity control valve V has a high resistance to disturbances and excellent control accuracy.

[0094] The main and sub-valve elements 51 and the pressure-sensitive valve member 52 are separate bodies, and a stopper 51 d is formed on the main and sub-valve elements 51 to restrict the axial rightward movement of the sliding valve element 90 . Therefore, the axial movement of the sliding valve element 90 can be restricted with a simple structure.

[0095] Furthermore, the pressure-sensitive valve member 52 has multiple through-holes 52d, thereby ensuring a large flow path cross-sectional area for discharging fluid from the PC port 14 to the suction chamber 3. Furthermore, since the multiple through-holes 52d are arranged at equal intervals in the circumferential direction, the stroke of the sliding valve element 90 can be shortened.

[0096] While 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 any changes or additions that do not depart from the gist of the present invention are also encompassed by the present invention.

[0097] For example, in the above embodiment, the sliding valve element reciprocates axially relative to the pressure-sensitive valve member. However, the present invention is not limited thereto. For example, the sliding valve element may reciprocate axially relative to the pressure-sensitive valve member while rotating and sliding.

[0098] Furthermore, in the above-described embodiment, an example has been described in which the main and sub valve bodies and the pressure-sensitive valve member are configured as separate bodies, but the two may be formed integrally.

[0099] In addition, the receiving surface of the sliding valve element may be formed to be perpendicular to the reciprocating direction of the main and sub valve elements and the sliding valve element.

[0100] In addition, the inner peripheral surface of the sliding valve element may not be formed in the same plane.

[0101] In addition, the sliding valve element can also be guided by the adapter 70 to reciprocate.

[0102] Alternatively, the base portion and the flange portion of the sliding valve element may be formed separately.

[0103] Alternatively, the base portion of the pressure-sensitive valve member and the flange portion serving as the support portion may be formed separately.

[0104] Furthermore, the communication passage and the fixed orifice that directly connect the control chamber 4 and the suction chamber 3 of the variable capacity compressor M do not need to be provided.

[0105] Furthermore, the auxiliary valve 54 may not be provided, and the step portion 51 b on the axial right side of the main and auxiliary valve elements 51 may function as a support member for receiving the axial load, and does not necessarily require a sealing function.

[0106] Alternatively, the pressure sensitive chamber 40 may be provided on the axial right side of the main valve chamber 20 where the solenoid 80 is provided, and the sub-valve chamber 30 may be provided on the axial left side of the main valve chamber 20 .

[0107] In addition, the coil spring 91 is not limited to a compression spring, and may be a tension spring or a spring having a shape other than a coil.

[0108] In addition, the coil spring 91 does not have to face the pressure sensitive chamber 40 .

[0109] In addition, the pressure sensitive body 60 does not need to use a coil spring inside.

[0110] Alternatively, the opening degree and opening time of the main valve 50 can be adjusted by controlling the duty cycle of the capacity control valve V, thereby controlling the flow rate of the fluid from the Pd port 12 to the Pc port 14. The amount of axial leftward movement of the sliding valve element 90 can be adjusted, and the opening degree of the through hole 52d of the pressure-sensitive valve member 52 can be adjusted by the axial left end portion of the base portion 90a of the sliding valve element 90. In this manner, the flow rate of the fluid flowing from the Pc port 14 to the Ps port 13 can be adjusted.

[0111] Explanation of symbols

[0112] 1: Outer casing; 2: Discharge chamber; 3: Suction chamber; 4: Control chamber; 10: Valve housing; 10a: Main valve seat; 10c: Annular convex portion; 11: Partition adjustment component; 12: Pd port (discharge port); 13: Ps port (suction port); 14: Pc port (control port); 20: Main valve chamber; 30: Sub-valve chamber; 40: Pressure-sensitive chamber; 50: Main valve; 51: Main and sub-valve cores (valve cores); 51c: Through hole; 51d: Stopper; 52: Pressure-sensitive valve component; 52a: Pressure-sensitive valve seat; 52b: Base; 52c: Flange portion (support portion); 52d: Through hole; 52e : Side; 53: Pressure-sensitive valve; 54: Auxiliary valve; 55: Intermediate connecting passage; 60: Pressure-sensitive body; 70: Connector; 70a: Axial right end; 80: Solenoid; 90: Sliding valve core; 90a: Base; 90b: Flange; 90c: Supporting surface; 90d: End face; 90e: End face; 90f: Side; 91: Coil spring (force-applying unit); 110: Valve housing; 152: Pressure-sensitive valve component; 152b: Base; 152d: Through hole; 190: Sliding valve core; 190b: Flange; M: Variable capacity compressor; V: Capacity control valve.

Claims

1. A capacity control valve comprising: a valve housing formed with a discharge port for passage of a discharge fluid having a discharge pressure, a suction port for passage of a suction fluid having a suction pressure, and a control port for passage of a control fluid having a control pressure; a main valve composed of a valve core driven by a solenoid and a main valve seat provided between the discharge port and the control port and capable of being contacted by the valve core; a pressure-sensitive body disposed in the pressure-sensitive chamber; as well as a pressure-sensitive valve component extending from the valve core toward the pressure-sensitive chamber and constituting a pressure-sensitive valve together with the pressure-sensitive body; An intermediate communication passage is formed on the valve core and the pressure-sensitive valve member. The control port and the suction port can be communicated through the intermediate communication passage by opening and closing the pressure-sensitive valve. The pressure-sensitive valve member is provided with a through hole communicating with the intermediate communication path, and a sliding valve core is provided. The sliding valve core slides relative to the pressure-sensitive valve member to open and close the through hole. An urging unit for urging the sliding valve element in an opening direction is provided on an outer diameter side of the sliding valve element.

2. The capacity control valve according to claim 1, wherein: The urging unit is disposed between the sliding valve element and a support portion formed on a front end side of the through hole of the pressure sensitive valve member.

3. The capacity control valve according to claim 1, wherein: The force applying unit is arranged in a state of being exposed to the pressure sensitive chamber.

4. The capacity control valve according to claim 1, wherein: The inner peripheral surface of the sliding valve element is formed into a flush plane.

5. The capacity control valve according to claim 1, wherein: The sliding valve element has a receiving surface formed thereon, the receiving surface facing the main valve.

6. The capacity control valve according to claim 5, wherein: The receiving surface is inclined relative to the reciprocating movement direction of the valve core.

7. The capacity control valve according to claim 1, wherein: The sliding valve element is configured to be capable of performing a stroke in a state in which the through hole is closed.

8. The capacity control valve according to claim 1, wherein The valve element and the pressure-sensitive valve member are separate bodies, and a stopper for restricting movement of the sliding valve element toward the main valve is formed on the valve element.

9. The capacity control valve according to any one of claims 1 to 8, wherein: A plurality of through holes are formed in the pressure-sensitive valve component.

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