valve

Abstract

The purpose of the present invention is to provide a valve that requires a small drive force of a drive source when the valve is closed.　A valve V1 comprises a valve housing 10 and a valve body 50 to be driven by a drive source 80, and causes the valve body 50 to be moved from a control region to a blocking region, to thereby control the flow rate of a fluid flowing inside a through-flow path 12 in the direction opposite to the blocking direction of the valve body 50. The valve V1 has a structure in which an effective pressure-receiving area where the pressure of the fluid acts on the valve body 50 in accordance with the stroke of the valve body 50 is changed over between the control region and the blocking region. The effective pressure-receiving area is narrower in the blocking region than in the control region.

Description

[Technical field]

[0001] The present invention relates to a valve for variably controlling a working fluid, and more particularly to a valve for controlling the discharge amount 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 compression pistons connected to the swash plate, and controls the amount of fluid discharged by changing the stroke amount of the pistons by changing the inclination angle of the swash plate. 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 capacity control valve as a valve that is opened and closed by the electromagnetic force of a solenoid as a driving source.

[0003] When the variable displacement compressor is in continuous operation, the displacement control valve is energized and controlled by the control computer. The electromagnetic force generated by the solenoid moves the valve disc in the axial direction, and the flow path between the discharge port and the control port is opened and closed by the valve, thereby performing normal control to adjust the control pressure Pc in the control chamber of the variable displacement compressor.

[0004] For example, in the displacement control valve shown in Patent Document 1, when the solenoid is not energized and the valve is in an open state, the fluid flows to the control port through a through passage communicating with a discharge port in the housing. When the solenoid is energized from this open state, the rod-shaped valve element moves toward a valve seat formed in the through passage, and is able to close the through passage. In this way, the pressure in the control pressure chamber of the variable displacement compressor is controlled by using a fluid with a discharge pressure Pd that is higher than the control pressure Pc.

[0005] Some displacement control valves control the flow rate of fluid from a control port to a suction port. Such displacement control valves control the pressure in the control pressure chamber of a variable displacement compressor by utilizing the pressure difference between the control pressure Pc and the suction pressure Ps, which is lower than the control pressure Pc. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2009-221965 A (pages 8 to 10, Figure 2) Summary of the Invention [Problem to be solved by the invention]

[0007] In a displacement control valve such as that disclosed in Patent Document 1, when the valve is closed, it is necessary to move the valve body in the opposite direction to the direction of the fluid flowing through the through passage, and a force from the fluid acts on the valve body in the opposite direction to the driving force of the solenoid. In particular, when the pressure of the fluid is high, the force that the valve body receives from the fluid is strong, and in order to respond to this state, a strong driving force is required for the solenoid.

[0008] The present invention has been made in view of the above-mentioned problems, and has an object to provide a valve in which the driving force of a driving source when the valve is closed is small. [Means for solving the problem]

[0009] In order to solve the above problems, the valve of the present invention comprises: A valve including a valve housing and a valve body driven by a drive source, the valve body being configured to move from a control region to a closed region to control a flow rate of a fluid flowing through a through passage in a direction opposite to a closing direction of the valve body, an effective pressure-receiving area of ​​the valve body, where the pressure of the fluid acts on the valve body, is switched between the control area and the closed area in accordance with a stroke of the valve body, The effective pressure-receiving area of ​​the blocked area is smaller than that of the controlled area. According to this, since the effective pressure receiving area is narrower in the closed region than in the control region and the force that the valve element receives from the fluid pressure is small, the driving force of the drive source that drives the valve element when the valve is closed may be small.

[0010] The through passage and the valve body may form a blocking portion capable of adjusting the flow rate of the fluid in the blocking region, and a throttling portion capable of adjusting the flow rate of the fluid in the control region. According to this, the flow rate in the blocked region and the flow rate in the controlled region can be adjusted separately by the blocking portion and the throttle portion. Therefore, by switching the effective pressure receiving area in the blocked region and the effective pressure receiving area in the controlled region according to the stroke of the valve disc, the effective pressure receiving area in the blocked region can be narrowed.

[0011] The throttle portion may have a constant opening area in the closed region. This reduces the effect that the fluid passing through the throttle portion has on the valve body when the valve is switched to the closed region.

[0012] The obstruction may be a poppet valve structure. This improves the sealing performance when the valve is closed.

[0013] The obstruction may be a spool valve arrangement. According to this, since the valve body does not substantially come into contact with the through flow passage, the sealing performance is less likely to deteriorate.

[0014] The valve body may have a cross-sectional area at a tip portion that is narrower than a cross-sectional area at a base portion. With this, the cross-sectional area of ​​the tip portion becomes the effective pressure-receiving area in the blocked region, and the cross-sectional area of ​​the base portion becomes the effective pressure-receiving area in the controlled region, so that the valve body has a simple structure.

[0015] The through-flow passage may have a stepped shape that is wider on the narrowed portion side than on the blocked portion side. According to this, the small diameter flow passage of the through-flow passage constitutes the blocked area, and the large diameter flow passage of the through-flow passage constitutes the controlled area, so that the blocking section and the throttle section can be simply configured.

[0016] The through-flow passage may have a tapered surface that constitutes the throttle portion. According to this, when switching from the blocked area to the controlled area and when switching from the controlled area to the blocked area, the flow rate of the fluid changes smoothly. [Brief description of the drawings]

[0017] [Figure 1] 1 is a cross-sectional view showing a state in which the capacity control valve according to the first embodiment of the present invention is opened in a non-energized state. [Diagram 2] 2 is an enlarged cross-sectional view showing a valve chamber of the displacement control valve of the first embodiment. FIG. [Diagram 3] 2 is an enlarged cross-sectional view showing a valve chamber of the displacement control valve of the first embodiment. FIG. [Figure 4] 2 is an enlarged cross-sectional view showing a valve chamber of the displacement control valve of the first embodiment. FIG. [Diagram 5] 2 is an enlarged cross-sectional view showing a valve chamber of the displacement control valve of the first embodiment. FIG. [Figure 6] 5 is a diagram for explaining a transition of an opening area in accordance with a stroke of a valve disc in the displacement control valve of the first embodiment. FIG. [Figure 7] 5 is a diagram for explaining the transition of a current used for the stroke of the valve disc and a Pc-Ps pressure difference in the displacement control valve of the first embodiment. FIG. [Figure 8] FIG. 6 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve according to a second embodiment of the present invention. [Figure 9] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve according to a third embodiment of the present invention. [Figure 10] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a displacement control valve according to a third embodiment. [Figure 11] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a displacement control valve according to a third embodiment. [Figure 12] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a displacement control valve according to a third embodiment. [Figure 13] 13 is a diagram for explaining a transition of an opening area in accordance with a stroke of a valve disc in a displacement control valve according to a third embodiment. FIG. [Figure 14] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve according to a fourth embodiment of the present invention. [Figure 15] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve in a first modified example of the fourth embodiment of the present invention. [Figure 16] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve in a second modified example of the fourth embodiment of the present invention. [Figure 17] FIG. 11 is an enlarged cross-sectional view showing a valve chamber of a capacity control valve in a third modified example of the fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A valve according to the present invention will be described below based on an embodiment. Note that although the embodiment will be described using a capacity control valve as an example, the present invention can also be applied to other uses. EXAMPLES

[0019] A displacement control valve as a valve according to a first embodiment will be described with reference to Fig. 1 to Fig. 7. In the following description, the left and right sides as viewed from the front of Fig. 1 will be referred to as the left and right sides of the displacement control valve. In particular, the left side of the drawing where the valve housing 10 is arranged will be referred to as the left side of the displacement control valve, and the right side of the drawing where the solenoid 80 as a drive source is arranged will be referred to as the right side of the displacement control valve.

[0020] The capacity control valve of the present invention is incorporated in a variable capacity compressor (not shown) used in the air conditioning system of an automobile or the like, and controls the discharge volume of the variable capacity compressor by variably controlling the pressure of a working fluid (hereinafter simply referred to as "fluid"), which is a refrigerant, thereby adjusting the air conditioning system to achieve a target cooling capacity.

[0021] First, the variable displacement compressor will be described. The variable displacement compressor has a casing that includes a discharge chamber, a suction chamber, a control chamber, and a number of cylinders. The variable displacement compressor is provided with a communication passage that directly connects the discharge chamber and the control chamber. This communication passage is provided with a fixed orifice 9 for balancing the pressures of the discharge chamber and the control chamber (see FIG. 1).

[0022] The variable displacement compressor includes a rotating shaft, a swash plate, and a plurality of pistons. The rotating shaft is driven to rotate by an engine (not shown) installed outside the casing. The swash plate is connected to the rotating shaft in a control chamber so as to be tiltable by a hinge mechanism. The pistons are connected to the swash plate and fitted in their respective cylinders so as to be capable of reciprocating motion. The variable displacement compressor uses a displacement control valve V1, which is driven to open and close by an electromagnetic force, to utilize the suction pressure Ps of the suction chamber that draws in the fluid, the discharge pressure Pd of the discharge chamber that discharges the fluid pressurized by the pistons, and the control pressure Pc of the control chamber that houses the swash plate, and by appropriately controlling the pressure in the control chamber, the inclination angle of the swash plate is continuously changed to change the stroke amount of the pistons, thereby controlling the discharge amount of the fluid.

[0023] 1, the capacity control valve V1 of the first embodiment incorporated in a variable capacity compressor adjusts the current flowing through the coil 86 constituting the solenoid 80 to control the opening and closing of the CS valve 50 in the capacity control valve V1. This controls the fluid flowing from the control chamber to the suction chamber, thereby variably controlling the control pressure Pc in the control chamber. Note that the discharge fluid at the discharge pressure Pd of the discharge chamber is constantly supplied to the control chamber via the fixed orifice 9, and the control pressure Pc in the control chamber can be increased by closing the CS valve 50 in the capacity control valve V1.

[0024] In the capacity control valve V1 of the first embodiment, the CS valve 50 is composed of a CS valve body 51 as a valve body, and a CS valve seat 15 formed on the inner circumferential surface of the valve housing 10. The CS valve 50 opens and closes by the CS valve body 51 moving toward and away from the CS valve seat 15 in the axial direction.

[0025] Next, the structure of the displacement control valve V1 will be described. As shown in Fig. 1, the displacement control valve V1 is mainly composed of a valve housing 10, a CS valve body 51, and a solenoid 80. The valve housing 10 is made of a metal material. The CS valve body 51 is arranged in the valve housing 10 so as to be able to reciprocate axially. The solenoid 80 is connected to the valve housing 10 and applies a driving force to the CS valve body 51.

[0026] As shown in FIG. 1, the solenoid 80 is mainly composed of a casing 81, a center post 82, the CS valve body 51, a movable iron core 84, a coil spring 85, and an exciting coil 86. The casing 81 has an opening 81a that opens to the left in the axial direction. The center post 82 is inserted into the opening 81a of the casing 81 from the left in the axial direction and is disposed between the inner diameter side of the casing 81 and the inner diameter side of the valve housing 10, and has a substantially cylindrical shape. The CS valve body 51 is inserted into the center post 82 and is capable of reciprocating in the axial direction, and its left end in the axial direction is disposed in the valve housing 10. The movable iron core 84 is inserted and fixed to the right end in the axial direction of the CS valve body 51. The coil spring 85 is disposed between the center post 82 and the movable iron core 84, and biases the movable iron core 84 to the right in the axial direction, which is the valve opening direction of the CS valve 50. The coil 86 is wound around the outside of the center post 82 via a bobbin.

[0027] The center post 82 includes a cylindrical portion 82b and an annular flange portion 82d. The cylindrical portion 82b is formed from a rigid body that is a magnetic material such as iron or silicon steel, and is formed with an insertion hole 82c that extends in the axial direction and through which the CS valve body 51 is inserted. The flange portion 82d extends in the outer diameter direction from the outer peripheral surface of the left end portion in the axial direction of the cylindrical portion 82b.

[0028] As shown in Fig. 1, the CS valve body 51 is composed of a tapered portion 51a, a large diameter portion 51b as a base, and a small diameter portion 51c, and also serves as a rod that is disposed to penetrate the coil 86 of the solenoid 80. The tapered portion 51a is made of a metal material or a resin material, and is a cone having an isosceles triangular cross section that tapers toward the tip, i.e., the left end in the axial direction. The large diameter portion 51b is a cylindrical body with a constant cross section. The small diameter portion 51c extends axially rightward from the inner diameter side of the right end in the axial direction of the large diameter portion 51b.

[0029] In the tapered portion 51a of the CS valve body 51, the portion that seats on the CS valve seat 15 and the portion further toward the tip side than that are referred to as the abutment portion 51d as the tip portion that can seat on the CS valve seat 15 (see the cross-hatched areas in Figs. 1 to 5). The CS valve 50 of this embodiment has a poppet valve structure.

[0030] The maximum radial cross-sectional area RS2 (see FIG. 2) of the contact portion 51d is approximately equal to the pressure-receiving area of ​​the CS valve seat 15 (i.e., the inner diameter cross-sectional area of ​​the small diameter flow passage 13), and is narrower than the radial cross-sectional area RS1 (see FIG. 2) of the large diameter portion 51b (RS2 <RS1)。

[0031] Further, a corner portion 51e is formed at the boundary between the tapered portion 51a and the large diameter portion 51b of the CS valve body 51. The cross-sectional area RS1 of the corner portion 51e is equal to the cross-sectional area RS1 of the large diameter portion 51b (see FIG. 2).

[0032] 1, a valve housing 10 is formed with a Ps port 11 and a Pc port 13. The Ps port 11 is connected to a suction chamber of the variable displacement compressor. The Pc port 13 is connected to a control chamber of the variable displacement compressor.

[0033] The Pc port 13 (sometimes referred to as the small diameter passage 13) is connected in communication with a large diameter passage 14 having a larger diameter than the Pc port 13. The small diameter passage 13 and the large diameter passage 14 constitute the through passage 12 of the present invention.

[0034] Further, a CS valve seat 15 is formed on the open end edge of the small diameter passage 13 on the large diameter passage 14 side.

[0035] 2 to 5, the large diameter flow passage 14 includes a bottom portion 14a, a peripheral wall surface 14b, and a tapered surface 14c. The bottom portion 14a has a CS valve seat 15 formed at its inner end and extends in the outer diameter direction, generally perpendicular to the axial direction. The peripheral wall surface 14b extends axially rightward, generally perpendicular to the outer diameter side end of the bottom portion 14a. The tapered surface 14c gradually expands in diameter from the axial right end of the peripheral wall surface 14b toward the axial right.

[0036] As shown in Fig. 1, a valve chamber 20 is formed inside the valve housing 10, and the axial left end portion of the CS valve element 51 is arranged in the valve chamber 20 so as to be able to freely reciprocate in the axial direction. The Ps port 11 extends radially inward from the outer circumferential surface of the valve housing 10 and communicates with the valve chamber 20, and the large diameter flow passage 14 forms part of the valve chamber 20. For ease of explanation, in Figs. 1 to 5, the boundary of the through passage 12 in the valve chamber 20 is indicated by an imaginary two-dot chain line B1.

[0037] A guide hole 10a is formed in the valve housing 10, on the solenoid 80 side of the valve chamber 20, in which the outer circumferential surface of the CS valve element 51 can slide in a substantially sealed state. A minute gap is formed between the inner circumferential surface of the guide hole 10a and the outer circumferential surface of the CS valve element 51 by being slightly separated in the radial direction, so that the CS valve element 51 can move smoothly relative to the valve housing 10 in the axial direction.

[0038] The valve housing 10 has a recess 10b formed on the inner diameter side of the right axial end, which recesses 10b toward the left in the axial direction, into which the flange portion 82d of the center post 82 is inserted and fixed from the right axial direction in a substantially sealed manner, and the casing 81 is further inserted and fixed from the right axial direction in a substantially sealed manner, thereby being connected together. The opening end of the guide hole 10a on the solenoid 80 side is formed on the inner diameter side of the bottom surface of the recess 10b of the valve housing 10.

[0039] Furthermore, when the capacity control valve V1 has the CS valve body 51 inserted into the large diameter flow passage 14 of the valve housing 10, the large diameter flow passage 14 has a tapered surface 14c (see Figure 2), and therefore the tapered surface of the tapered portion 51a and the outer peripheral surface of the large diameter portion 51b abut against the tapered surface 14c to guide the valve body radially, making it easy to align the CS valve body 51 with the large diameter flow passage 14.

[0040] Next, with reference to Figures 2 to 6, a description will be given of the manner in which the flow rate of the fluid flowing in from the Pc port 13 is controlled by the obstruction section 90 and the throttle section 91, which are configured by the shortest portion between the CS valve body 51 and the through flow passage 12.

[0041] The blocking portion 90 is composed of the contact portion 51d of the CS valve body 51 and the CS valve seat 15, and the opening area x of the blocking portion 90 is adjustable according to the stroke st of the CS valve body 51. The opening area x of the blocking portion 90 refers to the flow path area between the contact portion 51d and the CS valve seat 15.

[0042] In addition, since the abutment portion 51d of the CS valve body 51 has a tapered shape, the shortest distance between the abutment portion 51d and the CS valve seat 15 gradually becomes smaller as the abutment portion 51d moves in the valve closing direction, and therefore, as shown by the black solid line and the black dashed line in Figure 6, the opening area x of the occlusion portion 90 gradually becomes narrower (x1≦x(st1≦st≦st4)≦x4) as the CS valve body 51 moves in the valve closing direction.

[0043] 2 to 5, the throttle portion 91 is composed of a corner portion 51e of the CS valve body 51, and a peripheral wall surface 14b and a tapered surface 14c in the large diameter flow passage 14 of the through passage 12, and the opening area y of the throttle portion 91 is adjustable according to the stroke st of the CS valve body 51. The opening area y of the throttle portion 91 refers to the flow passage area between the corner portion 51e and the peripheral wall surface 14b or the tapered surface 14c.

[0044] Further, since the inclination angle of the tapered surface of the tapered portion 51a of the CS valve body 51 with respect to the axial direction is smaller than the inclination angle of the tapered surface 14c of the through-flow passage 12 with respect to the same axial direction, the opening area y of the throttle portion 91 changes depending on the position of the corner portion 51e.

[0045] Also, when the stroke range of the corner portion 51e of the CS valve body 51 is within the range of the peripheral wall surface 14b, that is, the closing region to be described later, the opening area y of the throttle portion 91 becomes constant as shown by the white chain line in FIG. 6 (y(st2 < st ≦ st4) = y2). Specifically, the shortest separation dimension between the corner portion 51e and the peripheral wall surface 14b is shorter than the shortest separation dimension between the corner portion 51e and the tapered surface 14c, and the shortest separation dimension between the corner portion 51e and the peripheral wall surface 14b within the same range is constant.

[0046] Also, when the stroke range of the corner portion 51e of the CS valve body 51 is within the range of the tapered surface 14c, that is, the control region to be described later, the opening area y of the throttle portion 91 gradually narrows as the CS valve body 51 moves in the valve closing direction, as shown by the solid white line in FIG. 6 (y1 ≦ y(st1 ≦ st ≦ st2) ≦ y2). Specifically, the shortest separation dimension between the corner portion 51e and the tapered surface 14c is shorter than the shortest separation dimension between the corner portion 51e and the peripheral wall surface 14b, and the shortest separation dimension between the corner portion 51e and the tapered surface 14c within the same range gradually decreases as the corner portion 51e moves in the valve closing direction.

[0047] Next, the operation in the normal control of the capacity control valve V1, mainly the opening and closing operation of the CS valve 50, will be described with reference to FIGS. 1 to 7. Note that the effective pressure receiving area in this specification is the pressure receiving area that mainly affects the stroke st of the CS valve body 51 among the opening area x of the closing portion 90 and the opening area y of the throttle portion 91 that can function as a pressure receiving area. The pressure of the fluid that affects the stroke st of the CS valve body 51 is mainly the control pressure Pc, and more precisely, the differential pressure between the control pressure Pc and the suction pressure Ps.

[0048] 1, in the capacity control valve V1, in a de-energized state, the movable iron core 84 is pressed axially rightward by the biasing force of the coil spring 85, thereby pressing the CS valve body 51 axially rightward. At this time, the solenoid 80 is not operating, the stroke st1 of the CS valve body 51 is 0, and the CS valve 50 is open (corresponding to FIG. 2).

[0049] Also, referring to FIG. 7, as shown by the solid black line, when current begins to flow through the capacity control valve V1, the stroke st of the CS valve body 51 remains at st1(0) until the current passing therethrough reaches or exceeds a predetermined value and the driving force generated by the solenoid 80 exceeds the biasing force of the coil spring 85 and the force acting on the CS valve body 51 from the fluid.

[0050] As shown by the solid black line in FIG. 7, when current begins to flow through the displacement control valve V1 and the current reaches a predetermined value or greater, the CS valve element 51 moves axially leftward.

[0051] Thereafter, referring to FIG. 6, as the applied current increases, the stroke st of the CS valve body 51 becomes longer in the order of st2 (corresponding to FIG. 3), st3 (corresponding to FIG. 4), and st4 (corresponding to FIG. 5).

[0052] At the stroke st4, the contact portion 51d of the CS valve element 51 is seated on the CS valve seat 15, closing the CS valve 50. At this time, the stroke st of the CS valve element 51 becomes maximum.

[0053] 6, when the stroke st of the CS valve body 51 is st1, the opening area x of the blocking portion 90 is x1, and the opening area y of the throttle portion 91 is y1. The opening area x1 is wider than the opening area y1 (x1>y1), and the flow rate of the control fluid that can pass through the throttle portion 91 is smaller than the flow rate of the control fluid that can pass through the blocking portion 90. The opening areas x1 and y1 are the maximum opening areas in this embodiment, and since both are sufficiently wide, the flow rate of the control fluid that can pass through is maximized, and as shown by the fine dot pattern in FIG. 2, the control fluid of the control pressure Pc flows from the Pc port 13 into the space from the small diameter flow path 13 to the Ps port 11 in the through flow path 12. At this time, the opening area z of the CS valve 50 is z1, which is the opening area y1 of the throttle portion 91.

[0054] 6, when the stroke st of the CS valve body 51 is st2, the opening area x of the blocking portion 90 is x2, and the opening area y of the throttling portion 91 is y2. The opening area x2 is greater than the opening area y2 (x2>y2), and the flow rate of the control fluid that can pass through the throttling portion 91 is less than the flow rate of the control fluid that can pass through the blocking portion 90. At this time, the opening area z of the CS valve 50 is z2, which is the opening area y2 of the throttling portion 91.

[0055] As a result, as shown by the fine dot pattern in Figure 3, the space from the small diameter passage 13 to the throttle section 91 in the through passage 12 becomes almost filled with control fluid of control pressure Pc flowing in from the Pc port 13.

[0056] As shown by the black dashed line and the white solid line in Fig. 6, in the stroke range st1 ≦ st ≦ st2 of the CS valve body 51, as the stroke changes from st1 to st2, the opening areas of the closing portion 90 and the throttle portion 91 gradually decrease. Until immediately before the stroke st2, the opening area y of the throttle portion 91 is smaller than the opening area x of the closing portion 90, and at the stroke st2, the opening area y is substantially the same as the opening area x. From this, it becomes possible to adjust the flow rate of the control fluid flowing from the Pc port 13 into the valve chamber 20 according to the opening area y of the throttle portion 91. At this time, a small Pc - Ps differential pressure mainly acts on the tapered portion 51a of the CS valve body 51. That is, the cross-sectional area RS1 of the large-diameter portion 51b of the CS valve body 51 becomes the effective pressure-receiving area.

[0057] Note that the stroke range st1 ≦ st ≦ st2 of the CS valve body 51 is the control range in this embodiment (see Figs. 6 and 7).

[0058] Referring to Fig. 6, when the stroke st of the CS valve body 51 is st3, the opening area x of the closing portion 90 becomes x3, and the opening area y of the throttle portion 91 becomes y2. Also, the opening area x3 is smaller than the opening area y2 (x3 < y2), and the flow rate of the control fluid that can pass through the closing portion 90 is less than the flow rate of the control fluid that can pass through the throttle portion 91. At this time, the opening area z of the CS valve 50 is z3 which is the opening area x3 of the closing portion 90.

[0059] As a result, as shown by the fine dotted pattern in Fig. 4, the space from the small-diameter flow path 13 to the closing portion 90 in the through-flow path 12 is substantially filled with the control fluid at the control pressure Pc flowing in from the Pc port 13. Also, in the space from the closing portion 90 to the throttle portion 91, since the opening area y of the throttle portion 91 is larger than the opening area x of the closing portion 90, as shown by the thick dotted pattern in Fig. 4, the fluid in the space that has passed through the closing portion 90 becomes lower in pressure than the fluid before passing through the closing portion 90.

[0060] Thus, in the stroke range st2 < st ≦ st3 of the CS valve body 51, a large Pc - Ps differential pressure acts on the CS valve body 51. Specifically, a high pressure acts on the contact portion 51d of the tapered portion 51a, and a small pressure acts on the tapered portion 51a on the downstream side of the contact portion 51d. That is, the cross-sectional area RS2 of the contact portion 51d of the CS valve body 51 becomes the effective pressure-receiving area.

[0061] Referring to FIG. 6, when the stroke st of the CS valve body 51 is st4, the opening area x of the closing portion 90 becomes x4, and the opening area y of the throttle portion 91 becomes y2. Also, the opening area x4 is narrower than the opening area y2 (x4 < y2) and is 0. That is, the CS valve 50 is closed, and the opening area z of the CS valve 50 is z4 which is the opening area x4 of the closing portion 90.

[0062] As a result, as shown by the fine dot pattern in FIG. 5, the space from the small-diameter flow path 13 to the closing portion 90 in the through-flow path 12 is filled with the control fluid of the control pressure Pc flowing in from the Pc port 13. Also, in the space from the closing portion 90 to the throttle portion 91, since the flow rate flowing in through the closing portion 90 becomes 0, it is in a state of being filled with the fluid of the suction pressure Ps.

[0063] Thus, in the stroke range st3 < st ≦ st4 of the CS valve body 51, an even larger Pc - Ps differential pressure acts on the CS valve body 51. Specifically, a high pressure acts on the contact portion 51d of the tapered portion 51a. That is, the cross-sectional area RS2 of the contact portion 51d of the CS valve body 51 becomes the effective pressure-receiving area.

[0064] Note that the stroke range st2 < st ≦ st4 of the CS valve body 51 is the closing region in this embodiment (see FIG. 6).

[0065] Also, with reference to the stroke st2, the opening area x of the closing portion 90 becomes narrower than the opening area y of the throttle portion 91, and the control region and the closing region are configured to switch.

[0066] As described above, in the closing region (st2 < st ≤ st4) of the CS valve body 51, the cross-sectional area RS2, which is smaller than the cross-sectional area RS1, becomes the effective pressure-receiving area, and the force received by the CS valve body 51 from the fluid decreases. From this, the driving force of the solenoid 80 that drives the CS valve body 51 during valve closing can be reduced (see Fig. 7). Also, in the control region (st1 ≤ st < st2), since the rising rate of the Pc - Ps differential pressure is small, the flow rate can be accurately adjusted according to the current (see Fig. 7).

[0067] Further, for example, if the effective pressure-receiving area of the valve body in the control region and the effective pressure-receiving area of the valve body in the closing region are substantially the same, as shown by the dashed-dotted line in Fig. 7, the current required until the valve is closed and the Pc - Ps differential pressure becomes maximum is larger than the current required until the CS valve 50 in this embodiment is closed and the Pc - Ps differential pressure becomes maximum, as shown by the solid line in Fig. 7.

[0068] Furthermore, if a structure is adopted in which the effective pressure-receiving area of the valve body in the control region and the effective pressure-receiving area of the valve body in the closing region are substantially the same and the reduction rate of the opening area with respect to the stroke st is large, although the valve can be closed with substantially the same current as in the present invention, the increase rate of the Pc - Ps differential pressure in the control region becomes large, so the control accuracy in the control region is inferior to that of this embodiment.

[0069] As described above, the capacity control valve V1 of this embodiment can individually adjust the flow rate in the closing region and the flow rate in the control region by the closing portion 90 and the throttle portion 91. Therefore, according to the stroke st of the CS valve body 51, the cross-sectional area RS2 as the effective pressure-receiving area in the closing region and the cross-sectional area RS2 as the effective pressure-receiving area in the control region are switched, and the effective pressure-receiving area in the closing region can be made narrow.

[0070] Also, since the opening area y2 in the closing region of the throttle portion 91 is constant, in the state where the closing region is switched, the influence of the fluid passing through the throttle portion 91 on the CS valve body 51 can be reduced.

[0071] In addition, since the blocking portion 90 has a poppet valve structure constituted by the CS valve element 51, which is a cone having an isosceles triangular cross section, and the CS valve seat 15, it is possible to improve the sealing performance when the valve is closed.

[0072] In addition, the tapered portion 51a of the CS valve body 51 is formed in a tapered shape, and the abutment portion 51d is inserted into the small diameter flow passage 13 of the through flow passage 12 and seats on the CS valve seat 15, thereby ensuring stable sealing when seated.

[0073] Furthermore, the abutment portion 51d of the CS valve body 51 is not limited to a cone having an isosceles triangular cross section as long as it is capable of seating on the CS valve seat 15 and the effective pressure-receiving area in the blocked region is narrower than the effective pressure-receiving area in the controlled region.

[0074] In addition, the CS valve body 51 has a maximum cross-sectional area of ​​the abutment portion 51d that is narrower than the cross-sectional area of ​​the large diameter portion 51b, the cross-sectional area of ​​the abutment portion 51d becomes the cross-sectional area RS2 as the effective pressure-receiving area in the blocked region, and the cross-sectional area of ​​the large diameter portion 51b becomes the cross-sectional area RS1 as the effective pressure-receiving area in the controlled region, so that the CS valve body 51 can be constructed simply.

[0075] In addition, since the through flow passage 12 has a stepped shape in which the large diameter flow passage 14 constituting the throttling section 91 is wider radially than the small diameter flow passage 13 constituting the blocking section 90, the small diameter flow passage 13 of the through flow passage 12 constitutes the blocking section 90 and the large diameter flow passage 14 of the through flow passage 12 constitutes the throttling section 91, the blocking section 90 and the throttling section 91 can be constructed simply.

[0076] In addition, since the through flow passage 12 has a tapered surface 14c that forms the throttling section 91, the flow rate of the fluid can be smoothly changed when switching from the blocked area to the controlled area and when switching from the controlled area to the blocked area.

[0077] In addition, since the through-flow path 12 forms a rectangular cross-sectional space by the bottom portion 14a and the peripheral wall surface 14b, the control fluid is likely to stay in this space in the control region. Therefore, the cross-sectional area RS2 as the effective pressure-receiving area in the blocked region and the cross-sectional area RS1 as the effective pressure-receiving area in the control region can be more reliably switched according to the stroke st of the CS valve body 51.

[0078] In addition, in this embodiment, in the control region, the form in which the opening area y of the throttle portion 91 is narrower than or substantially the same as the opening area x of the blocking portion 90 is illustrated. However, the present invention is not limited to this. The opening areas x and y with respect to the stroke st of the CS valve body 51 in the control region may be substantially the same over the strokes st1 to st2. In such a form, in the stroke range (st1 ≦ st < st2) of the control region, the opening area x with respect to the stroke st of the CS valve body 51 becomes the same as the opening area y with respect to the same stroke st, and in the entire stroke range (st1 ≦ st ≦ st4), the opening area z of the CS valve 50 with respect to the stroke st of the CS valve body 51 becomes the same as the opening area x with respect to the same stroke st.

Embodiment

[0079] The capacity control valve according to Embodiment 2 will be described with reference to FIG. 8. In addition, the description of the same configuration as that of the above Embodiment 1 will be omitted.

[0080] As shown in FIG. 8, in the capacity control valve V2 of the present Embodiment 2, the large-diameter flow path 114 of the through-flow path 112 formed in the valve housing 110 includes a bottom portion 114a and a peripheral wall surface 114b. The bottom portion 114a is formed in a tapered shape that gradually increases in diameter toward the right in the axial direction with the CS valve seat 15 formed at the inner end. The peripheral wall surface 114b extends axially rightward substantially parallel to the axial direction from the outer diameter side end of the bottom portion 114a.

[0081] In this way, even if the opening area yy of the throttling portion 191 is constant regardless of the stroke st of the CS valve body 51, the opening area x of the occlusion portion 90 becomes narrower than the opening area yy of the throttling portion 191, so that the effective pressure-receiving area switches from the cross-sectional area RS1 to the cross-sectional area RS2, and therefore the driving force of the solenoid 80 that drives the CS valve body 51 when the valve is closed can be reduced.

[0082] In addition, in the through-flow passage 112, the fluid that has passed through the blocking portion 90 is guided by the tapered bottom portion 114a that is inclined along the direction in which the fluid flows, making the flow less likely to be disturbed. This makes it possible to more stably adjust the flow rate from the Pc port 13. EXAMPLES

[0083] A displacement control valve V3 according to a third embodiment will be described with reference to Figures 9 to 13. Note that a description of the same configuration as in the first and second embodiments will be omitted.

[0084] As shown in FIG. 9, in the capacity control valve V3 of this embodiment 3, the CS valve body 151 has a columnar portion 151d of constant cross section as a tip portion at the axial left end portion of the tapered portion 151a, and the cross-sectional area RS3 of the columnar portion 151d is slightly narrower than the inner diameter cross-sectional area of ​​the small diameter flow passage 13.

[0085] The CS valve 150 of this embodiment has a spool valve structure.

[0086] The blocking portion 190 is composed of the columnar portion 151d of the CS valve body 151 and the peripheral wall surface 13a of the small diameter flow passage 13, and the opening area X of the blocking portion 190 can be adjusted according to the stroke ST of the CS valve body 51. The opening area X of the blocking portion 190 refers to the flow passage area between the columnar portion 151d and the peripheral wall surface 13a.

[0087] Further, when the stroke range of the columnar portion 151d of the CS valve body 151 is within the large-diameter flow path 14, the opening area X of the closing portion 190 gradually becomes narrower as the CS valve body 51 moves in the valve closing direction, as shown by the black chain line and the black solid line in FIG. 13 (X1 ≦ X (ST1 ≦ ST < ST3) < X3).

[0088] Also, when the stroke range of the columnar portion 151d of the CS valve body 151 is within the small-diameter flow path 13, the opening area X of the closing portion 190 becomes constant, as shown by the black solid line in FIG. 13 (X (ST3 ≦ ST ≦ ST4) = X3).

[0089] Referring to FIGS. 11 and 12, in the stroke range ST3 ≦ ST ≦ ST4 of the columnar portion 151d of the CS valve body 151, the space where the opening area X of the closing portion 190 is very narrow at X3 has an axial dimension L that becomes longer as it approaches from ST3 to ST4 (L1(0) ≦ L ≦ L2(MAX)).

[0090] Also, as it approaches from ST3 to ST4, the space of the opening area X3 of the closing portion 190 becomes longer in the axial direction, making it difficult for the fluid to pass through the closing portion 190. Therefore, the flow rate gradually decreases as it approaches ST4. Since the axial dimension L2 is long at ST4, the leakage from the Pc port 13 to the valve chamber 20 is small, and a closed state can be ensured.

[0091] Referring to FIG. 13, when the capacity control valve V3 is in a non-energized state or when the energized current is less than a predetermined value, the stroke ST of the CS valve body 151 becomes ST1(0) (corresponding to FIG. 9). When the energized current becomes equal to or greater than the predetermined value, the stroke ST becomes longer in the order of ST2 (corresponding to FIG. 10), ST3 (corresponding to FIG. 11), and ST4 (corresponding to FIG. 12).

[0092] Referring to FIG. 13, when the stroke ST of the CS valve body 151 is ST1, the opening area X of the closing portion 190 becomes X1, and the opening area Y of the throttle portion 91 becomes Y1. Also, the opening area Y1 is narrower than the opening area X1 (Y1 < X1). At this time, the opening area Z of the CS valve 150 is Z1, which is the opening area Y1 of the throttle portion 91.

[0093] As shown by the fine dot pattern in Figure 9, since the opening areas X1 and Y2 are both sufficiently large, the control fluid at control pressure Pc flows from the Pc port 13 into the space from the small-diameter passage 13 to the Ps port 11 in the through passage 12.

[0094] 13, when the stroke ST of the CS valve body 151 is ST2, the opening area X of the blocking portion 190 is X2, and the opening area Y of the throttling portion 91 is Y2. The opening areas X2 and Y2 are substantially the same (X2=Y2), and the flow rate of the control fluid that can pass through the blocking portion 190 and the flow rate of the control fluid that can pass through the throttling portion 91 are substantially the same. In other words, the opening area Z of the CS valve 150 is Z2, which is the opening area Y2 of the throttling portion 91.

[0095] 10, the control fluid at the control pressure Pc flows from the Pc port 13 into the space in the through passage 12 from the small diameter passage 13 to the throttle portion 91.

[0096] 13, in the stroke range ST1≦ST≦ST2 of the CS valve element 151, the opening areas of the obstruction portion 190 and the throttle portion 91 gradually decrease as the stroke transitions from ST1 to ST2, making it possible to adjust the flow rate of the control fluid flowing from the Pc port 13 into the valve chamber 20. At this time, the small Pc-Ps pressure difference acts mainly on the columnar portion 151d and the tapered portion 151a of the CS valve element 51. In other words, the cross-sectional area RS1 of the large diameter portion 51b of the CS valve element 51 becomes the effective pressure-receiving area.

[0097] Incidentally, the stroke range ST1≦ST≦ST2 of the CS valve element 151 is the control range in this embodiment (see FIG. 13).

[0098] Referring to FIG. 13, when the stroke ST of the CS valve body 151 is ST3, the opening area X of the closing portion 190 becomes X3, and the opening area Y of the throttle portion 91 becomes Y2. Also, the opening area X3 is narrower than the opening area Y2 (X3 < Y2), and the flow rate of the control fluid that can pass through the closing portion 190 is less than the flow rate of the control fluid that can pass through the throttle portion 91.

[0099] Further, the axial dimension L of the space of the opening area X3 of the closing portion 190 is L1 where L is 0. That is, the opening area Z of the CS valve 150 is Z3 which is the opening area X3 of the closing portion 190.

[0100] As a result, as shown by the fine dotted pattern in FIG. 11, the space from the small-diameter flow path 13 to the closing portion 190 in the through-flow path 12 is almost filled with the control fluid of the control pressure Pc flowing in from the Pc port 13. Also, in the space from the closing portion 190 to the throttle portion 91, since the opening area Y of the throttle portion 91 is wider than the opening area X of the closing portion 190, as shown by the thick dotted pattern in FIG. 11, the fluid in the space that has passed through the closing portion 190 becomes lower in pressure than the fluid before passing through the closing portion 190.

[0101] Thus, in the stroke range ST2 < ST ≦ ST3, a large Pc - Ps differential pressure acts on the CS valve body 51. Specifically, a high pressure acts on the end face 51f of the columnar portion 151d, and a small pressure acts on the tapered portion 151a. That is, the cross-sectional area RS3 of the columnar portion 151d of the CS valve body 51 becomes the effective pressure-receiving area.

[0102] Referring to FIG. 13, when the stroke ST of the CS valve body 151 is ST4, similar to the case where the stroke is ST3, the opening area X of the closing portion 190 becomes X3, and the opening area Y of the throttle portion 91 becomes Y2 (X3 < Y2).

[0103] Further, the axial dimension L of the space of the opening area X3 of the closing portion 190 is L2 which is the maximum. That is, the opening area Z of the CS valve 150 is Z3 which is the opening area X3 of the closing portion 190, and the CS valve 150 is in a closed valve state.

[0104] As a result, as shown by the fine dot pattern in Fig. 12, the space from the small-diameter flow path 13 to the closing portion 190 in the through-flow path 12 is filled with the control fluid of the control pressure Pc flowing in from the Pc port 13. Further, in the space from the closing portion 190 to the throttle portion 91, since the flow rate flowing in through the closing portion 190 is almost zero, it is filled with the fluid of the suction pressure Ps.

[0105] Thus, in the stroke range ST3 ≦ ST ≦ ST4 of the CS valve body 51, an even larger Pc - Ps differential pressure acts on the CS valve body 51. Specifically, a high pressure acts on the end face 51f of the columnar portion 151d. That is, the cross-sectional area RS3 of the columnar portion 151d of the CS valve body 51 becomes the effective pressure-receiving area.

[0106] Note that the stroke range ST2 < ST ≦ ST4 of the CS valve body 151 is the closing region in this embodiment (see Fig. 13).

[0107] Further, with reference to the stroke ST2, the magnitude relationship between the opening area X of the closing portion 190 and the opening area Y of the throttle portion 91 is reversed, and the opening area X of the closing portion 190 becomes narrower than the opening area Y of the throttle portion 91, so that the control region and the closing region are switched.

[0108] As described above, in the capacity control valve V3 of this embodiment, the closing portion 190 has a spool valve structure. In the closing region (ST2 < ST ≦ ST4) of the CS valve body 151, the cross-sectional area RS3, which is narrower than the cross-sectional area RS1, becomes the effective pressure-receiving area, and the force received by the CS valve body 151 from the fluid becomes smaller. From this, the driving force of the solenoid 80 that drives the CS valve body 51 at the time of valve closing can be reduced. Also, in the control region, since the rising rate of the Pc - Ps differential pressure is small, the flow rate can be accurately adjusted according to the current.

[0109] Also, in the capacity control valve V3 of this embodiment, since the closing portion 190 has a spool valve structure, the CS valve body 151 does not substantially contact the through-flow path 12, so that deterioration of the sealing performance can be suppressed.

[0110] In this embodiment, the blocking portion 190 is configured as a spool valve structure, but the present invention is not limited to this and may be configured as a poppet valve in which the tapered portion 151a seats on the CS valve seat 15. With such a configuration, it is possible to take advantage of the characteristics of the spool valve structure while ensuring the valve closing characteristic of the poppet valve structure. EXAMPLES

[0111] A displacement control valve V4 according to the fourth embodiment will be described with reference to Fig. 14. Note that a description of the configuration that is the same as that of the first to third embodiments will be omitted.

[0112] As shown in FIG. 14, in the displacement control valve V4 of the fourth embodiment, a small-diameter columnar portion 251d of a CS valve body 251 is formed at the tip of a large-diameter portion 51b.

[0113] The annular end face 251g of the large diameter portion 51b is capable of being seated on the CS valve seat 115 formed on the inner diameter side end of the bottom portion 14a of the large diameter flow passage 14. The CS valve 250 of this embodiment has a poppet valve structure with a nose at the tip. In addition, in Figure 14, the CS valve body 251 when the valve is closed is shown by a two-dot chain line.

[0114] The closing portion 290 is composed of an end face 251g of the large diameter portion 51b and the CS valve seat 115, and the opening area r of the closing portion 290 is adjustable according to the stroke st of the CS valve body 251. The opening area r of the closing portion 290 refers to the flow path area between the end face 251g and the CS valve seat 115.

[0115] The throttle portion 291 is composed of the columnar portion 251d of the CS valve body 251 and the peripheral wall surface 13a of the small diameter flow passage 13, and the opening area q of the throttle portion 291 can be adjusted according to the stroke st of the CS valve body 251. The opening area q of the throttle portion 291 refers to the flow passage area between the columnar portion 251d and the peripheral wall surface 13a.

[0116] The gap between the columnar portion 251d and the small diameter flow passage 13 is wide, and the opening area r is sufficiently wider than the opening area between the columnar portion 151d and the small diameter flow passage 13 in the embodiment 3. As a result, in the throttle portion 291, the flow rate of the fluid can be adjusted until the opening area p of the blocking portion 290 becomes narrower than the opening area q of the throttle portion 291.

[0117] In this manner, the stroke range in which the flow rate of the fluid can be adjusted by the throttle portion 291 is the control region in this embodiment. In the control region, the small Pc-Ps differential pressure mainly acts on the end face 251g of the large diameter portion 51b. That is, the cross-sectional area RS1 of the large diameter portion 51b of the CS valve body 251 becomes the effective pressure-receiving area. Also, in the control region, the opening area q of the throttle portion 291 becomes the opening area r of the CS valve 250.

[0118] In the blocking portion 290, as the opening area p of the blocking portion 290 becomes narrower than the opening area q of the throttle portion 291, it becomes more difficult for the fluid to pass from the small diameter flow path 13 to the large diameter flow path 14. Then, the end face 251g of the large diameter portion 51b is seated on the CS valve seat 115, thereby closing the valve.

[0119] In this manner, the range of the stroke where the blocking portion 290 makes it difficult for the fluid to pass from the small diameter flow path 13 to the large diameter flow path 14 is the blocked region in this embodiment. In the blocked region, in the control region, a large Pc-Ps differential pressure acts on the CS valve body 251 in a range that is approximately the same as the inner diameter cross-sectional area of ​​the small diameter flow path 13. That is, the area RS4 of this range becomes the effective pressure-receiving area. Also, in the blocked region, the opening area p of the blocking portion 290 becomes the opening area r of the CS valve 250.

[0120] As described above, in the capacity control valve V4 of this embodiment, the closing portion 290 is formed in the large diameter flow passage 14, and the throttling portion 291 is formed in the small diameter flow passage 13, and the stroke st of the CS valve body 251 reverses the size relationship between the opening area p of the closing portion 290 and the opening area q of the throttling portion 291, and the opening area p of the closing portion 290 becomes narrower than the opening area q of the throttling portion 291, thereby switching between the control region and the closed region. In other words, the area RS4 as the effective pressure receiving area in the closed region and the cross-sectional area RS1 as the effective pressure receiving area in the control region switch according to the stroke st of the CS valve body 251. Therefore, the driving force of the solenoid 80 that drives the CS valve body 251 when the valve is closed can be reduced.

[0121] In the fourth embodiment, an example has been described in which the throttle portion 291 is configured by the columnar portion 251d of the CS valve body 251 and the peripheral wall surface 13a of the small diameter flow passage 13, but the throttle portion may be configured by the outer peripheral surface of the large diameter portion 51b and the inner peripheral surface of the large diameter flow passage 14. This also applies to the following modified examples.

[0122] As shown in FIG. 15, as a first modification of the capacity control valve V4, a tapered surface and a protruding portion 251a are formed between the columnar portion 251d and the large diameter portion 51b of the CS valve body 351. The tapered surface gradually expands in diameter from the axial right end of the columnar portion 151d toward the outer diameter direction and the axial leftward. The protruding portion 251a is formed in a mortar shape, and includes an outer circumferential surface that is continuous with the outer circumferential surface of the large diameter portion 51b and the outer circumferential end of the tapered surface. The CS valve 350 may be configured as a poppet valve structure in which the corner portion 151e of the protruding portion 251a is seated on the CS valve seat 115. With this configuration, the corner portion 151e is seated on the CS valve seat 115, so that the valve can be closed reliably.

[0123] As shown in FIG. 16, as a second modified example of a displacement control valve V4, a CS valve 450 may be configured as a poppet valve in which a tapered portion 351a of a CS valve body 451 is seated on a CS valve seat 215 of a valve housing 210.

[0124] The blocking portion 390 may be composed of a tapered bottom portion 214a having a CS valve seat 215 formed at its inner end and gradually increasing in diameter toward the right in the axial direction, and a tapered portion 351a of the CS valve body 451.

[0125] Also, the axial dimension of the large diameter flow passage 214 of the through passage 212 can be made shorter. For example, the axial dimension of the peripheral wall surface 214b can be made shorter than the axial dimension of the peripheral wall surface 114b in the embodiment 2. In other words, a communication passage that communicates with the outside of the valve housing may be formed in the peripheral wall surface 114b in the embodiment 2, in addition to the Ps port 11 and the Pc port 13.

[0126] As shown in FIG. 17, in a third modified example of a displacement control valve V4, a large diameter passage 314 of a through passage 312 in a valve housing 310 may have only a tapered bottom portion 214a.

[0127] 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.

[0128] For example, in the above embodiment, the obstruction portion and the throttle portion are described as being configured to control the flow rate of a fluid at the control pressure Pc, but the present invention is not limited to this and may be configured to control the flow rate of a fluid at the discharge pressure Pd.

[0129] In addition, although the configuration has been described in which one throttle section is formed, this is not limiting, and for example, a configuration may be provided in which a medium-diameter flow passage communicating with a small-diameter flow passage and a large-diameter flow passage communicating with the medium-diameter flow passage are provided, a first throttle section formed by the peripheral wall surface of the medium-diameter flow passage and a valve body, and a second throttle section formed by the peripheral wall surface of the large-diameter flow passage and the valve body, and the fluid control is switched in the order of the second throttle section, the first throttle section, and the closing section as the stroke increases, that is, a plurality of throttle sections may be formed in the axial direction of the valve body. With such a configuration, the driving force of the solenoid that drives the valve body when the valve is closed can be reduced in multiple stages.

[0130] In addition, the valve seat has been described as being formed in the valve housing, but this is not limited thereto, and the valve seat may be formed by assembling a valve seat member formed separately from the valve housing to the valve housing.

[0131] Further, the valve body has been described as being configured to also function as a rod that is disposed to pass through the coil of the solenoid, but this is not limiting, and the valve body and the rod may be separate bodies.

[0132] As for the shapes of the valve disc and the through flow passage, in the first and second embodiments, a poppet valve structure in which the valve disc has an acute-angled tip, and in the third embodiment, a spool valve structure in which the valve disc has a columnar tip, are described. However, as long as the effective pressure-receiving area in which the pressure of the fluid acts on the valve disc in accordance with the stroke of the valve disc is a structure in which the closure area is narrower than the control area, a structure as in the fourth embodiment may be used, and the shapes of the valve disc and the through flow passage can be changed as appropriate. [Explanation of symbols]

[0133] 10 Valve housing 12 Through passage 13 PS port, small diameter passage (closed side of through passage) 14 Large diameter flow passage (throttling side of through flow passage) 15 CS valve seat 50 CS valve 51 CS valve body 51b Large diameter part (base part) 51d Contact part (tip part) 80 Solenoid (drive source) 90 Occlusion 91 Squeezing section 110~310 Valve housing 112~312 Through passage 114~314 Large diameter flow passage 115,215 CS valve seat 150~450 CS valve 151~451 CS valve body 151d Columnar part (tip) 190~390 Occlusion 191,291 Squeezing section RS1 Cross-sectional area (cross-sectional area of ​​base, effective pressure-receiving area of ​​control area) RS2 Cross-sectional area (cross-sectional area of ​​tip, effective pressure-receiving area of ​​blocked area) RS3 Cross-sectional area (cross-sectional area of ​​tip, effective pressure-receiving area of ​​blocked area) RS4 Cross-sectional area (effective pressure-receiving area of ​​the blocked area) st,ST CS valve body stroke V1~V4 Capacity control valve (valve) p,x,X Opening area of ​​the occlusion q, y, Y Opening area of ​​throttle section r,z,Z CS valve opening area

Claims

1. A valve including a valve housing and a valve body driven by a drive source, the valve body being configured to control a flow rate of a fluid flowing through a through passage in a direction opposite to a closing direction of the valve body by moving the valve body from a control region to a closing region that is closer to a closing position of the valve body than the control region, an effective pressure-receiving area of ​​the valve body, where the pressure of the fluid acts on the valve body, is switched between the control area and the closed area in accordance with a stroke of the valve body, The effective pressure receiving area is narrower in the blocked area than in the controlled area, the through passage and the valve body constitute a blocking portion capable of adjusting a flow rate of the fluid in the blocking region and a throttling portion capable of adjusting a flow rate of the fluid in the control region, The through passage has a stepped shape consisting of a small diameter passage and a large diameter passage which is wider than the small diameter passage, and the small diameter passage of the through passage constitutes the blocking portion and the large diameter passage constitutes the throttling portion.

2. The valve according to claim 1 , wherein the throttle portion has a constant opening area in the closed region.

3. 3. The valve according to claim 1, wherein the obstruction portion is a poppet valve.

4. 3. The valve according to claim 1, wherein the obstruction portion is a spool valve structure.

5. 5. The valve according to claim 1, wherein the through passage has a tapered surface that constitutes the throttle portion.

Images