valve

Abstract

The present invention provides a valve capable of controlling a fluid with high precision.　Between a valve housing (10) and a valve body (51) are disposed a second compartmentalization member (60) and a first compartmentalization member (30) capable of extending / retracting in the axial direction. The first compartmentalization member (30) compartmentalizes one space (S2) and a rear surface space (S3) in a sealed manner. The second compartmentalization member (60) is fixed in a sealed manner to the valve body (51) and compartmentalizes an internal space (S4), which is independent in another space (S1), in a sealed manner. The internal space (S4) communicates with said one space (S2) via a separate communication means (57).

Description

[Technical Field]

[0001] The present invention relates to a valve for controlling a working fluid. [Background technology]

[0002] Valves used to control working fluids in various industrial fields have a valve seat and a valve body that can be attached to and detached from the valve seat, and the pressure and flow rate of the working fluid can be controlled by adjusting the valve opening.

[0003] Typical valve types include spool valves, butterfly valves, and lift valves. In a spool valve, the spool, which is the valve element, moves parallel to the opening, which is the valve seat. In a butterfly valve, the valve element has a pivot axis. In a lift valve, the valve element moves perpendicular to the opening, which is the valve seat. Of these valves, the lift valve is the most suitable for flow rate and pressure control.

[0004] An example of a lift valve is a displacement control valve for a variable displacement compressor used in an air conditioning system for an automobile or the like. A variable displacement compressor includes a rotating shaft, a swash plate, and compression pistons. The rotating shaft is driven to rotate by an engine. The swash plate is connected to the rotating shaft so that its inclination angle can be adjusted. The compression pistons are connected to the swash plate. A variable displacement compressor controls the amount of fluid discharged by changing the inclination angle of the swash plate, thereby changing the stroke of the pistons. The inclination angle of the swash plate can be continuously changed by appropriately controlling the pressure in a control chamber that houses the swash plate using a displacement control valve that is opened and closed by electromagnetic force, utilizing 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 pistons, and the control pressure Pc in a control chamber that houses the swash plate.

[0005] The displacement control valve of Patent Document 1 includes a valve housing, a valve seat, and a valve element. The valve housing defines a primary pressure space through which a control fluid having a control pressure Pc passes, and a secondary pressure space through which a control fluid having a suction pressure Ps passes. The valve seat is located between the primary pressure space and the secondary pressure space. The valve element has a rod portion disposed in a back space on the solenoid side from the primary pressure space, and its valve contact portion is disposed so as to be able to approach and separate from the valve seat. This displacement control valve adjusts the control pressure Pc in the control chamber by moving the valve element using electromagnetic force generated by the solenoid.

[0006] A communication passage is also formed in the valve housing. This communication passage connects the secondary pressure space with the back space. This allows the secondary pressure space and the back space to be at the same pressure through the communication passage. Furthermore, because the communication passage does not create a pressure difference on either side of the valve disc in the axial direction, precise rod control can be achieved in response to the current applied to the solenoid. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO 2020 / 110925 (page 10, Figure 3) Summary of the Invention [Problem to be solved by the invention]

[0008] In the displacement control valve of Patent Document 1, the rod portion of the valve element is inserted into a guide hole provided between a primary pressure space and a back space in a valve housing. The rod portion is guided by the guide hole to slide stably. However, there is a minute gap between the outer circumferential surface of the rod portion and the inner circumferential surface of the guide hole. This causes a small amount of control pressure Pc in the primary pressure space to leak into the back space from between the outer circumferential surface of the rod portion and the guide hole, which could make it difficult to control the control pressure Pc in the primary pressure space with high precision.

[0009] The present invention has been made in view of these problems, and has as its object to provide a valve that can control fluid with high precision. [Means for solving the problem]

[0010] In order to solve the above problems, the valve of the present invention comprises: a valve housing having a primary pressure space and a secondary pressure space; a valve seat disposed between the primary pressure space and the secondary pressure space; a valve element that is driven in an axial direction by a drive source to seat on or move away from the valve seat; A valve including a back space adjacent to one of the primary pressure space and the secondary pressure space, and a communication means for communicating the other of the primary pressure space and the secondary pressure space, A first partition member and a second partition member that are extendable and contractible in the axial direction are disposed between the valve housing and the valve body, the first partitioning member partitions the one space and the rear space in a sealed manner, the second partitioning member is hermetically fixed to the valve body and hermetically partitions an independent internal space within the other space, The internal space is in communication with the one space via another communication means. With this, the working fluid in one space is introduced into the internal space of the second partitioning member through another communication means, and the fluid pressure of the working fluid in one space acts on both axial sides of the valve body. Therefore, while maintaining pressure balance while ensuring the flow of fluid in one space, the influence of the working fluid in one space on the valve body is reduced, and the one space and the back space are partitioned in a sealed state, making it possible to control the fluid with high precision.

[0011] The effective pressure-receiving area of ​​the first partition member may be smaller than the effective pressure-receiving area of ​​the second partition member. According to this, the first partitioning member can be configured to have a smaller radial dimension than the second partitioning member, so that a large flow of fluid can be ensured in one of the spaces.

[0012] The sum of the effective pressure-receiving area of ​​the first partition member and the effective pressure-receiving area of ​​the second partition member is equal to the effective pressure-receiving area of ​​the valve body. According to this, since the sum of the effective pressure-receiving area of ​​the first partition member and the effective pressure-receiving area of ​​the second partition member is equal to the effective pressure-receiving area of ​​the valve body, the force due to the fluid pressure in one space acting on the valve body and the force due to the fluid pressure in the other space are each canceled out, so that the valve body can be operated with high precision regardless of the fluid pressure, and the fluid can be controlled with high precision.

[0013] The other communication means may be a through hole extending through the valve body. This allows the internal space of the second partition member to communicate with one of the spaces via the through hole provided in the valve body, eliminating the need to provide a separate communication means outside the valve housing, making the structure simple and compact.

[0014] The other communication means may be a communication passage that communicates the one space with the internal space outside the valve housing. In this way, since the one space and the internal space are connected by a communication passage separate from the valve body, it is possible to avoid the risk that the movement of the valve body will affect the state of communication between the one space and the internal space. Also, the valve body can be adapted to various shapes.

[0015] The first partitioning member and the second partitioning member may be bellows having a bellows-shaped body portion. According to this, the bellows-shaped body of the bellows expands and contracts in the axial direction, thereby suppressing axial wobble of the valve body. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a cross-sectional view showing a displacement control valve according to a first embodiment of the present invention. [Figure 2] FIG. 4 is an enlarged cross-sectional view of a main part showing a state in which the capacity control valve is closed. [Figure 3] FIG. 4 is an enlarged cross-sectional view of a main part showing a state in which the capacity control valve is opened. [Figure 4]FIG. 4 is a cross-sectional view showing a displacement control valve according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A valve according to the present invention will be described below with reference to the following examples. Although the embodiments will be described using a displacement control valve as an example, the present invention can also be applied to other uses. [Example]

[0018] A displacement control valve according to a first embodiment will be described with reference to Figures 1 to 3. In the following description, the left and right sides as viewed from the front of Figure 1 will be referred to as the left and right sides of the displacement control valve. Specifically, the left side of the drawing where the valve housing 10 is located will be referred to as the left side of the displacement control valve, and the right side of the drawing where the solenoid 80 is located will be referred to as the right side of the displacement control valve.

[0019] The capacity control valve of the present invention is incorporated into a variable capacity compressor (not shown) used in the air conditioning system of an automobile, etc. This capacity control valve variably controls the pressure of a working fluid (hereinafter simply referred to as "fluid"), which is a refrigerant, thereby controlling the discharge rate of the variable capacity compressor and adjusting the air conditioning system to achieve a target cooling capacity.

[0020] First, we will explain the variable displacement compressor. The variable displacement compressor has a casing that includes a discharge chamber, a suction chamber, a control chamber, and multiple 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 in the discharge chamber and the control chamber (see Figure 1).

[0021] The variable displacement compressor includes a rotating shaft, a swash plate, and multiple pistons. The rotating shaft is driven to rotate by an engine (not shown) installed outside the casing. The swash plate is tiltably connected to the rotating shaft within a control chamber via a hinge mechanism. Multiple pistons are connected to the swash plate and fitted to each cylinder for free reciprocating motion. The variable displacement compressor uses a displacement control valve V1, which is electromagnetically driven to open and close, to appropriately control the pressure within the control chamber by 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 pistons, and the control pressure Pc in the control chamber that houses the swash plate. The variable displacement compressor controls the discharge rate of fluid by continuously changing the inclination angle of the swash plate to change the stroke of the pistons.

[0022] As shown in Fig. 1, the displacement control valve V1 of this embodiment 1 incorporated in a variable displacement compressor adjusts the current flowing through a coil 86 constituting a solenoid 80 serving as a drive source to control the opening and closing of a CS valve 50 in the displacement control valve V1. As a result, the displacement control valve V1 variably controls the control pressure Pc in the control chamber by controlling the fluid flowing from the control chamber to the suction chamber. Note that discharge fluid at a discharge pressure Pd in ​​the discharge chamber is constantly supplied to the control chamber via a fixed orifice 9. As a result, the control pressure Pc in the control chamber can be increased by closing the CS valve 50 in the displacement control valve V1.

[0023] In the capacity control valve V1 of the first embodiment, the CS valve 50 is composed of a valve disc 56 and a CS valve seat 40a serving as a valve seat. The CS valve seat 40a is formed on a cylindrical valve seat member 40 that is press-fitted and fixed into the communication hole portion 10b of the valve housing 10. The CS valve 50 opens and closes when a tapered abutment portion 54 formed on the axial right side of the CS valve disc 51 of the valve disc 56 moves toward and away from the CS valve seat 40a in the axial direction. The valve disc 56 of the first embodiment is composed of the CS valve disc 51 serving as a valve element and the rod 20 serving as a rod element.

[0024] 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 and a valve seat member 40 made of a metal material, a CS valve element 51, a rod 20, a solenoid 80, a first bellows 30 serving as a first partitioning member, and a second bellows 60 serving as a second partitioning member. The CS valve element 51 is disposed within the valve housing 10 so as to be able to reciprocate axially. The rod 20 is disposed axially to the right of the CS valve element 51. The solenoid 80 is connected to the valve housing 10 and applies a driving force to the rod 20 and the CS valve element 51. The first bellows 30 is disposed between the valve housing 10 and the rod 20 in a sealed state. The second bellows is fixed in a sealed state axially to the left of the CS valve element 51, and defines an independent internal space S4.

[0025] As shown in FIGS. 1 and 2, the CS valve body 51 is formed with a leading end shaft portion 52, a large diameter portion 53, a contact portion 54, and a rear end shaft portion 55 in this order from the left end in the axial direction.

[0026] The front end shaft portion 52 has approximately the same diameter as the rear end shaft portion 55, and the large diameter portion 53 has a larger diameter than the front end shaft portion 52 and the rear end shaft portion 55. A through hole 57 (see FIG. 2) is formed in the large diameter portion 53 as another communication means that penetrates the large diameter portion 53 in the axial direction. This through hole 57 is formed to have a constant cross section.

[0027] The contact portion 54 is formed between the large diameter portion 53 and the rear end shaft portion 55, and has a tapered shape that reduces in diameter from the left side in the axial direction to the right side in the axial direction.

[0028] A primary pressure space S1, which serves as the other space, is formed on the axial left side of the valve housing 10. The primary pressure space S1 communicates with the control chamber via an inlet port 11 that penetrates radially. A secondary pressure space S2, which serves as one space, is formed on the axial right side of the primary pressure space S1 in the valve housing 10. The secondary pressure space S2 communicates with the discharge chamber via an outlet port 12 that penetrates radially.

[0029] The valve housing 10 is formed with a recess 10a that is recessed axially rightward from the left end in the axial direction and has an open left end in the axial direction.

[0030] The left axial end of the valve housing 10 is closed by a cover member 13, and the space surrounded by the recess 10a and the cover member 13 forms the primary pressure space S1. The cover member 13 is screwed and fixed to the left end of the valve housing 10, and its axial fixed position relative to the valve housing 10 is adjustable.

[0031] Additionally, a second bellows 60 and a coil spring 14 serving as a first biasing means are disposed between the cover member 13 and the CS valve body 51. The second bellows 60 is formed in the shape of a bellows cylinder that is expandable and contractible in the axial direction. The coil spring 14 biases the CS valve body 51 axially rightward, which is the valve closing direction of the CS valve 50.

[0032] The second bellows 60 is composed of a body 61, a cover member 13, and a large diameter portion 53 of the CS valve body 51. The body 61 is made of metal and formed in a bellows shape. The cover member 13 closes the opening at the left axial end of the body 61. The large diameter portion 53 closes the opening at the right axial end of the body 61. This hermetically separates the internal space S4 of the second bellows 60 from the primary pressure space S1. The left end of the through-hole 57 communicates with this internal space S4. The body 61 of the second bellows 60 may be made of a material other than metal.

[0033] The coil spring 14 is a compression spring, and is disposed inside the second bellows 60, i.e., in the internal space S4. More specifically, the tip shaft portion 52 of the CS valve body 51 is inserted into the inside of the coil spring 14. That is, the tip shaft portion 52 of the CS valve body 51 functions as a fitting portion that fits onto the coil spring 14.

[0034] The valve housing 10 also has a recess 10c recessed axially leftward on the inner diameter side of the right axial end, and a communication hole 10b that communicates in the axial direction is formed between the recesses 10a and 10c. The communication hole 10b has a smaller diameter than the recesses 10a and 10c.

[0035] Additionally, a first bellows 30 is fixed in a sealed state to the right axial end of the communication hole portion 10b. The space surrounded by this communication hole portion 10b and the first bellows 30 forms a secondary pressure space S2. The right end of the through hole 57 communicates with this secondary pressure space S2.

[0036] The first bellows 30 has a cylindrical body portion 31, a fixing plate portion 32, and a ring portion 33, and is generally U-shaped in radial cross section. The cylindrical body portion 31 has bellows that are expandable and contractible in the axial direction. The fixing plate portion 32 closes an opening at the left axial end of the body portion 31. The ring portion 33 is provided at the right axial end of the body portion 31, and is press-fitted and fixed in the small-diameter hole portion at the right axial end of the communicating hole portion 10b.

[0037] The body 31, the fixing plate 32, and the ring 33 are made of metal. The fixing plate 32 and the ring 33 are formed to be thicker than the body 31 and are more rigid than the body 31. The body 31, the fixing plate 32, and the ring 33 may be made of different materials, but it is preferable that the fixing plate 32 and the ring 33 be more rigid than the body 31. The body 31, the fixing plate 32, and the ring 33 may also be made of a material other than metal.

[0038] A guide recess 34 recessed axially rightward is formed in the center of the left surface of the fixed plate portion 32. A rear end shaft portion 55 of the CS valve body 51 is fitted into this guide recess 34.

[0039] The valve seat member 40 includes a cylindrical portion 41 and an annular protrusion 42. The cylindrical portion 41 is press-fitted into the communication hole portion 10b. The annular protrusion 42 protrudes radially outward from the left axial end of the cylindrical portion 41. The inner diameter of the cylindrical portion 41 is larger than the rear end shaft portion 55 of the CS valve body 51.

[0040] The valve seat member 40 is fixed in a sealed state to the valve housing 10. More specifically, the valve seat member 40 is fixed by being press-fitted from the left in the axial direction into the left end of a communicating hole 10b that penetrates the bottom of the recess 10a. Furthermore, the annular protrusion 42 abuts against the bottom end surface 10d of the recess 10a, preventing excessive insertion of the valve seat member 40 into the communicating hole 10b and positioning the valve seat member 40 in the axial direction.

[0041] The valve seat member 40 also has a CS valve seat 40a formed on the inner diameter side of the left end in the axial direction, and the CS valve seat 40a has a tapered shape that gradually reduces in diameter toward the right in the axial direction.

[0042] The flange portion 82d of the center post 82 is fitted and fixed from the axial right side in a sealed state into the recess 10c of the valve housing 10. Furthermore, the casing 81 is fitted and fixed from the axial right side onto the valve housing 10, thereby connecting them integrally.

[0043] A through hole 15 is formed in the valve housing 10 as a communication means. The through hole 15 opens to the bottom surfaces of the recesses 10a, 10c at both axial ends and extends in the axial direction. The through hole 15 is formed with a constant cross section and communicates with the primary pressure space S1 and the back space S3 within the solenoid 80.

[0044] As shown in FIG. 1 , the solenoid 80 is mainly composed of a casing 81, a center post 82, a rod 20, a movable iron core 84, a coil spring 85 as a second biasing means, an exciting coil 86, and a sleeve 87. 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. The rod 20 is inserted into the center post 82 and is freely reciprocable in the axial direction, and its left axial end is disposed within the valve housing 10. The right axial end of the rod 20 is inserted into and fixed to the movable iron core 84. The coil spring 85 biases the movable iron core 84 to the left 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. The sleeve 87 houses a part of the center post 82, the movable iron core 84, the coil spring 85 and a part of the rod 20, and is formed in a cylindrical shape with a bottom.

[0045] The center post 82 includes a cylindrical portion 82b and a 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 has an insertion hole 82c that extends axially and through which the rod 20 is inserted. The flange portion 82d is formed in an annular shape and extends radially outward from the outer peripheral surface of the left axial end of the cylindrical portion 82b.

[0046] Coil spring 85 is a compression spring, and is disposed between movable iron core 84 and sleeve 87. The left axial end of coil spring 85 is fitted into recess 84a formed in the right axial end of movable iron core 84. The biasing force of coil spring 85 is smaller than that of coil spring 14.

[0047] The back space S3 within the solenoid 80 is mainly the space within the sleeve 87 on the back side of the CS valve body 51 partitioned from the secondary compressed air space S2. Specifically, the back space S3 includes the space within the first bellows 30, the space between the recess 10c and the left end of the center post 82, the space within the center post 82, and the spaces on the left and right of the movable iron core 84 within the sleeve 87.

[0048] The rod 20 is inserted through the insertion hole 82c of the center post 82, and the right end in the axial direction of the rod 20 is inserted and fixed to the movable iron core 84. Also, the left end in the axial direction of the rod 20 is inserted into the body 31 of the first bellows 30. Further, the left end face in the axial direction of the rod 20 abuts against the right face of the fixed plate portion 32. Note that the left end face in the axial direction of the rod 20 may be fixed to the right face of the fixed plate portion 32 by an adhesive, welding, or the like.

[0049] Also, as shown in FIG. 2, the gap L1 between the outer peripheral surface of the rod 20 and the inner peripheral surface of the ring portion 33 in the first bellows 30 is smaller than the gap L2 between the outer peripheral surface of the rod 20 and the inner peripheral surface of the insertion hole 82c of the center post 82 (L1 < L2).

[0050] According to this, when the rod 20 tilts slightly during operation or when the pressure of the operating fluid is applied to the rod 20, it abuts against the inner peripheral surface of the ring portion 33 and the inclination of the rod 20 is restricted. Therefore, the axial play of the rod 20 and the CS valve body 51 can be prevented and stable operation can be achieved. That is, the ring portion 33 functions as an inclination restricting portion of the rod.

[0051] Also, as shown in FIG. 2, the effective pressure receiving area A of the CS valve body 51 is formed to be the sum of the effective pressure receiving area B of the first bellows 30 and the effective pressure receiving area C of the second bellows 60 (A = B + C). Also, the effective pressure receiving area B of the first bellows 30 is formed to be smaller than the effective pressure receiving area C of the second bellows 60 (B < C). The pressure of the operating fluid acting on the CS valve body 51 will be described in detail later.

[0052] Next, the opening and closing operation of the capacity control valve V1 will be described.

[0053] First, the de-energized state of the capacity control valve V1 will be described. As shown in Figures 1 and 2, in the capacity control valve V1, in the de-energized state, the CS valve element 51 is pressed axially rightward, i.e., in the valve closing direction, by the biasing force of the coil spring 14, which is greater than the biasing force of the coil spring 85, so that the abutment portion 54 of the CS valve element 51 seats on the CS valve seat 40a, and the CS valve 50 is closed.

[0054] Specifically, the abutment portion 54 of the CS valve body 51, which is also tapered so as to widen toward the left side in the axial direction, comes into contact with and seats on the CS valve seat 40a, which is tapered so as to widen toward the left side in the axial direction.

[0055] At this time, the rightward axial direction is taken as positive, and the CS valve body 51 is subjected to the biasing force (F sp1 ) and the force (F P1 ) and the force due to the pressure P2 of the working fluid in the secondary pressure space S2 (-F P2 ) and the biasing force of the coil spring 85 (-F sp2 ) and the biasing force of the first bellows 30 (-F BW1 ) and the biasing force of the second bellows 60 (F BW2 ) is acting on the CS valve body 51 (i.e., the right direction is positive, and the force F rod =F sp1 -F sp2 +F P1 -F P2 -F BW1 +F BW2 is at work).

[0056] Furthermore, at this time, the force due to the pressure P1 of the working fluid in the primary pressure space S1 and the force due to the pressure P2 of the working fluid in the secondary pressure space S2 acting in the axial direction of the CS valve body 51 are almost canceled out, so that the CS valve body 51 is not affected by the working fluid in the primary pressure space S1 and the secondary pressure space S2.

[0057] Specifically, in the primary pressure space S1, the pressure P1 of the working fluid acts in the axial right direction on an area obtained by subtracting the effective pressure-receiving area C of the second bellows 60 from the effective pressure-receiving area A of the CS valve body 51 at the left end face in the axial direction of the CS valve body 51. Furthermore, the working fluid in the primary pressure space S1 is supplied to the back space S3 through the through-hole 15 provided in the valve housing 10, and in the first bellows 30, the pressure P1 of the working fluid acts in the axial left direction on the effective pressure-receiving area B of the first bellows 30. That is, the CS valve body 51 is subjected to a force (F P1 )=P1×(ABC) is in effect.

[0058] In addition, the effective pressure receiving area A of the CS valve element 51 is the sum of the effective pressure receiving area B of the first bellows 30 and the effective pressure receiving area C of the second bellows 60 (A=B+C), so the force (F P1 ) is almost zero.

[0059] On the other hand, the pressure P2 of the working fluid in the secondary pressure space S2 acts on the CS valve body 51 in a force (F P2 )=-P2×(ABC) is at work.

[0060] In addition, the effective pressure receiving area A of the CS valve element 51 is the sum of the effective pressure receiving area B of the first bellows 30 and the effective pressure receiving area C of the second bellows 60 (A=B+C), so the force (F P2 ) is almost zero.

[0061] That is, the right direction is positive, and the CS valve body 51 is substantially subjected to a force F rod =F sp1 -F sp2 -F BW1 +F BW2 is acting, and the biasing force of the coil spring 14 (F sp1 ) and the biasing force (F BW2 ) is the biasing force of the coil spring 85 (F sp2 ) and the biasing force (FBW1 ) is greater than the sum of (F sp1 +F BW2 >F sp2 +F BW1 ), the CS valve 50 is pressed in the valve closing direction and is closed.

[0062] Next, the energized state of the displacement control valve V1 will be described. As shown in Fig. 3, in the energized state (i.e., during normal control, so-called duty control), the displacement control valve V1 generates an electromagnetic force (F sol ) is the force F rod Exceeds (F sol >F rod ), the movable core 84 is attracted toward the center post 82, i.e., to the left in the axial direction. Furthermore, the rod 20 and the CS valve element 51 fixed to the movable core 84 also move leftward in the axial direction, i.e., in the valve opening direction, similar to the movable core 84, and the abutment portion 54 of the CS valve element 51 moves away from the CS valve seat 40a, opening the CS valve 50.

[0063] Furthermore, when the solenoid 80 is driven, the tip shaft portion 52 of the CS valve element 51 comes into contact with the cover member 13, thereby restricting the CS valve element 51 from moving further away from the CS valve seat 40a.

[0064] At this time, the CS valve body 51 is subjected to an electromagnetic force (F sol ), and a force F r od is acting on the CS valve body 51 (i.e., the right direction is positive, and the force F rod -F sol is at work).

[0065] In this way, the displacement control valve V1 is driven by the electromagnetic force (F sol ) and the biasing force of the coil spring 14 (F sp1 ) and the biasing force of the coil spring 85 (-F sp2 ) and the biasing force of the first bellows 30 (-F BW1 ) and the biasing force (F BW2 ) and the difference (F sp1 -F sp2 -FBW1 +F BW2 The pressure P1 of the working fluid in the primary pressure space S1 can be appropriately controlled by adjusting the valve opening of the CS valve 50, which is adjusted based on the balance between the pressure P1 and the pressure P2.

[0066] As described above, the first bellows 30 and the second bellows 60 are attached between the valve housing 10 and the CS valve disc 51, the first bellows 30 dividing the secondary pressure space S2 and the back space S3, the second bellows 60 being hermetically fixed to the CS valve disc 51 and dividing an independent internal space S4 within the primary pressure space S1, the internal space S4 communicating with the secondary pressure space S2 via the through-hole 57. With this, the body 61 of the second bellows 60 is hermetically attached to the left axial end face of the CS valve disc 51, so that the area over which the pressure P1 of the working fluid in the primary pressure space S1 acts axially rightward on the CS valve disc 51 is reduced, and the effective pressure-receiving area B of the first bellows 30 for balancing the force acting axially rightward can be made smaller than the effective pressure-receiving area A of the CS valve disc 51.

[0067] Therefore, when the CS valve 50 is open, pressure balance is maintained while ensuring the flow of working fluid from the primary pressure space S1 through the secondary pressure space S2 to the suction chamber, while reducing the effect of the working fluid in the secondary pressure space S2 on the CS valve body 51. In addition, the first bellows 30 hermetically separates the secondary pressure space S2 from the back space S3, preventing the working fluid in the back space S3 from leaking into the secondary pressure space S2 through the gap between the communicating hole 10b and the rod 20, allowing for highly accurate control of the working fluid in the primary pressure space S1.

[0068] Furthermore, the effective pressure-receiving area B of the first bellows 30 and the effective pressure-receiving area C of the second bellows 60 are each formed smaller than the effective pressure-receiving area A of the CS valve body 51, so that the radial dimensions of the valve housing 10 can be made compact while ensuring the valve orifice area of ​​the CS valve seat 40a.

[0069] Furthermore, the effective pressure-receiving area B of the first bellows 30 is smaller than the effective pressure-receiving area C of the second bellows 60. This allows the first bellows 30 to be configured smaller than the second bellows 60, ensuring a large flow of working fluid in the secondary pressure space S2.

[0070] Furthermore, since the first bellows 30 can be made small, the secondary pressure space S2 portion of the valve housing 10 can be made radially compact while ensuring a flow path for the through hole 15 formed on the outer diameter side of the secondary pressure space S2 in which the first bellows 30 is arranged.

[0071] In addition, since the sum of the effective pressure receiving area B of the first bellows 30 and the effective pressure receiving area C of the second bellows 60 is equal to the effective pressure receiving area A of the CS valve body 51 (A=B+C), the force (F P1 ) and the force (F P2 ) are cancelled out. Therefore, the CS valve element 51 can be operated with high precision regardless of the pressures P1, P2 of the working fluid in the primary pressure space S1 and the secondary pressure space S2, and the fluid can be controlled with high precision.

[0072] The secondary pressure space S2 and the internal space S4 are communicated with each other via a through hole 57 that extends through the CS valve body 51. As a result, the secondary pressure space S2 and the internal space S4 can be communicated with each other via the through hole 57 provided in the CS valve body 51, so there is no need to provide a separate communication means outside the valve housing 10, and the structure can be made simple and compact.

[0073] In addition, the first bellows 30 and the second bellows 60 have accordion-shaped body portions 31, 61, respectively, which expand and contract in the axial direction, thereby suppressing axial vibration during operation of the valve body 56 and not impeding the drive of the CS valve body 51 and the rod 20.

[0074] Furthermore, the first bellows 30 and the second bellows 60 bias the valve disc 56 in opposite axial directions, thereby stably supporting the valve disc 56. In addition, the valve disc 56 is supported in a state where it is sandwiched between the coil spring 14, which biases the valve in a valve-closing direction, and the coil spring 85, which biases the valve in a valve-opening direction, in an opposing axial position, thereby suppressing axial wobble of the valve disc 56 and preventing sliding between the rod 20 and the valve housing 10. This allows the gap between the valve housing 10 and the rod 20 to be increased; in other words, since no minute gap is formed between the valve housing 10 and the rod 20, it is possible to prevent frictional forces from affecting the drive of the rod 20 and to prevent contaminants from getting caught in the minute gap.

[0075] Furthermore, the left end of the body 61 of the second bellows 60 is fixed in a sealed manner to the right surface of the cover member 13, whose axial fixed position relative to the valve housing 10 is adjustable. Therefore, the biasing force of the second bellows 60 and the volume of the internal space S4 can be easily adjusted by moving the cover member 13 axially relative to the valve housing 10.

[0076] Furthermore, since the tip shaft portion 52 of the CS valve body 51 is fitted inside the coil spring 14, axial wobble of the valve body 56 is suppressed.

[0077] The first bellows 30 also has a fixed plate portion 32, a ring portion 33, and a bellows-shaped body portion 31. The fixed plate portion 32 is fixed to the left end surface of the rod 20, the ring portion 33 is fixed to the valve housing 10, and the body portion 31 connects the fixed plate portion 32 and the ring portion 33. This prevents the rod 20 from passing through the fixed plate portion 32, thereby preventing working fluid from leaking from a gap between the rod 20 and the first bellows 30. Furthermore, because the bellows-shaped body portion 31 expands and contracts in the axial direction, the fixed plate portion 32 and the ring portion 33 can be made thick to increase their strength.

[0078] The outer peripheral surface of the ring portion 33 is fixed to the inner peripheral surface of the valve housing 10. Specifically, the ring portion 33 is press-fitted and fixed to the inner peripheral surface of the valve housing 10, so that the ring portion 33 can be easily attached to the valve housing 10 without the need for a fixing means. Furthermore, the ring portion 33 does not move in the radial direction, so axial wobble of the body portion 31 can be reliably suppressed.

[0079] Furthermore, the body portion 31 extends from the ring portion 33 toward the secondary pressure space S2. That is, the first bellows 30 is disposed within the secondary pressure space S2, which allows the back space S3 to be made compact. In other words, the first bellows 30 is not disposed on the back space S3 side, so the first bellows 30 does not affect the structure of the solenoid 80.

[0080] Furthermore, the CS valve 51 and rod 20 that constitute the valve element 56 are separate members, and the CS valve 51 is fixed to the fixed plate portion 32, making it easy to assemble the CS valve 50. Specifically, the CS valve 50 can be assembled by fixing the fixed plate portion 32 of the first bellows 30 to the rod 20, press-fitting and fixing the ring portion 33 of the first bellows 30 to the valve housing 10 to assemble the solenoid 80 and the valve housing 10, fixing the valve seat member 40 to the valve housing 10, and connecting the CS valve 51 to the fixed plate portion 32 of the first bellows 30 by penetrating the valve seat member 40. In other words, assembly can be easily achieved by inserting the valve seat member 40 and the CS valve 51 from the left in the axial direction, even without having to split the valve housing 10 in half, for example.

[0081] Furthermore, a guide recess 34 recessed axially rightward is formed in the center of the left surface of the fixing plate portion 32 of the first bellows 30, and the rear end shaft portion 55 of the CS valve body 51 is adapted to fit into this guide recess 34. As a result, the CS valve body 51 and the first bellows 30 are guided relatively in the axial direction by the guide recess 34, and therefore the CS valve body 51 and the first bellows 30 can be aligned with each other.

[0082] In this embodiment, the through hole 57 is provided on the outer diameter side of the tip shaft portion 52 and the rear end shaft portion 55 in the large diameter portion 53 of the CS valve body 51, but the present invention is not limited to this, and for example, a through hole may be provided that axially passes through the tip shaft portion 52, the large diameter portion 53, and the rear end shaft portion 55. This can reduce the effect that the body portion 61 of the second bellows 60, which expands and contracts, has on the communication state of the through hole. [Example]

[0083] Next, a displacement control valve according to a second embodiment will be described with reference to Fig. 4. Note that a description of the same configuration as in the previous embodiment will be omitted.

[0084] 4, the CS valve element 510 of the displacement control valve V2 of the second embodiment is mainly composed of a support body 520 and a spherical body 530. The CS valve element 510 is fixed in a sealed state to the right end of the second bellows 600. The spherical body 530 is supported by the right end of the support body 520.

[0085] Support body 520 has support portion 520a and tip shaft portion 520b. Support portion 520a is open to the right and has a U-shaped cross section. Tip shaft portion 520b protrudes to the left from the center of the left surface of support portion 520a. A sphere 530 is fitted inside support portion 520a, and a coil spring 14 is fitted into tip shaft portion 520b.

[0086] The spherical body 530 has a diameter larger than that of the CS valve seat 400a provided in the valve housing 100. Furthermore, when the CS valve body 510 is in the closed state, the spherical body 530 is in contact with the CS valve seat 400a over the entire circumference.

[0087] Moreover, first bellows 300 has the same configuration as first bellows 30 of Example 1 except that fixing plate portion 320 thereof does not have guide recess 34, and fixing plate portion 320 is configured to directly abut against sphere 530. Similarly, second bellows 600 has the same configuration as second bellows 60 of Example 1.

[0088] In the second embodiment, the primary pressure space S1' and the back space S3' are connected by a first communication passage R1, which serves as a communication means disposed outside the valve housing 100. More specifically, one end of the first communication passage R1 is connected to a flow path that connects the control chamber and the primary pressure space S1', and the other end is connected to the back space S3'.

[0089] In the second embodiment, the secondary pressure space S2' and the internal space S4' are connected by a second communication passage R2, which serves as another communication means disposed outside the valve housing 10. More specifically, one end of the second communication passage R2 is connected to a flow path connecting the suction chamber and the secondary pressure space S2', and the other end is connected to a through-hole 130a extending in the axial direction provided in the cover member 130, and is connected to the internal space S4' via the through-hole 130a.

[0090] In this way, the secondary pressure space S2' and the internal space S4' are connected to each other by the second communication passage R2 that is separate from the CS valve element 510, which prevents movement of the CS valve element 510 from affecting the state of communication between the secondary pressure space S2' and the internal space S4'. For example, it is possible to prevent problems such as the second communication passage R2 being blocked by movement of the CS valve element 510. Furthermore, since the second communication passage R2 is not formed in the CS valve element 510, the CS valve element 510 can be adapted to various shapes.

[0091] Furthermore, since the primary pressure space S1' and the rear space S3' are connected to each other by the first communication passage R1, which is separate from the valve housing 100, the valve housing 100 can be made as compact as possible.

[0092] 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.

[0093] For example, in the above-mentioned Examples 1 and 2, a configuration was exemplified in which the effective pressure-receiving area of ​​the first partition member was smaller than the effective pressure-receiving area of ​​the second partition member, but this is not limited to this, and the effective pressure-receiving area of ​​the first partition member may be slightly larger than the effective pressure-receiving area of ​​the second partition member, or the effective pressure-receiving area of ​​the first partition member and the effective pressure-receiving area of ​​the second partition member may be equal.

[0094] Furthermore, in the above-mentioned first and second embodiments, a form of canceling the pressure of the working fluid acting on both axial sides of the CS valve body is exemplified, but as long as the effect of the pressure of the working fluid acting on both axial sides of the CS valve body can be reduced, the pressure of the working fluid acting on one axial side of the CS valve body may be slightly greater than the pressure of the working fluid acting on the other axial side.

[0095] In addition, in the first and second embodiments, the valve element and the rod element are configured as separate members, but the present invention is not limited to this and the valve element and the rod element may be integrated. Furthermore, in the first embodiment, the valve element is exemplified as having a tapered shape, but this can be freely modified. Furthermore, in the second embodiment, the CS valve seat 400a is exemplified as having a right-angled corner, but it may also be shaped as a tapered shape, for example.

[0096] In addition, in the first and second embodiments, the end face of the fixing plate is fixed to the end face of the rod, but this is not limiting, and the end face of the rod does not necessarily have to be fixed to the end face of the fixing plate. Even if the end face of the rod is not fixed to the end face of the fixing plate, the first and second biasing means can maintain the end face of the rod and the end face of the fixing plate in contact with each other.

[0097] Furthermore, in the first and second embodiments, the fixed plate portion and the valve element are separate bodies, but the fixed plate portion and the valve element may be integrated.

[0098] In addition, in the above-mentioned Example 1, an example was given in which the valve element is fitted and fixed in a guide recess provided in the fixed plate portion, but a guide recess may be provided in the valve element and a convex portion protruding from the fixed plate portion may be fitted into the guide recess.

[0099] In addition, in the first and second embodiments, the primary pressure space, secondary pressure space, and back space are formed in this order from the left in the axial direction, but this is not limiting, and the positions of the primary pressure space and the secondary pressure space may be reversed. Specifically, the back space may be formed adjacent to the primary pressure space.

[0100] Furthermore, in the first and second embodiments, a normally closed valve has been described, but the present invention is not limited to this and may also be a normally open valve.

[0101] Furthermore, in the first and second embodiments, the valve element is disposed in the primary pressure space, but the valve element may be disposed in the secondary pressure space.

[0102] In addition, in the first and second embodiments, the first and second partitioning members always apply a biasing force to the valve body, but the first and second partitioning members may be capable of expanding and contracting in the axial direction, and may not apply a biasing force to the valve body. Also, the first and second partitioning members may not have a biasing force.

[0103] In addition, in the first and second embodiments, the first and second biasing means are compression springs, but they may be tension springs, for example. Furthermore, the first and second biasing means are not limited to coil springs, and one or both of the first and second biasing means may be leaf springs or the like.

[0104] In addition, in the first and second embodiments, the first and second biasing means are provided, but only one of them may be provided and the other may be omitted. For example, in the case of a normally closed valve, the second biasing means for biasing in the valve opening direction may not be provided. Also, in the case of a normally open valve, the first biasing means for biasing in the valve closing direction may not be provided.

[0105] In addition, in the first and second embodiments, the first biasing means is disposed in the primary pressure space, but the location where the first biasing means is disposed may be freely changed. For example, the first biasing means may be disposed in the secondary pressure space or the back space (between the center post and the movable iron core).

[0106] In addition, in the first and second embodiments, the second biasing means is disposed in the rear space, but the location where the second biasing means is disposed may be freely changed. For example, the second biasing means may be disposed in the secondary pressure space.

[0107] Furthermore, in the first and second embodiments, the first partitioning member is disposed in the secondary pressure space, but the first partitioning member may be disposed in the rear space.

[0108] Furthermore, in the first and second embodiments, the first and second partitioning members are bellows having bellows-shaped body portions, but the present invention is not limited to this, and the body portions may be any member as long as they are expandable and contractible.

[0109] In addition, in the first and second embodiments, the second partitioning member is disposed between the valve body and the cover member that constitutes the wall at the left end of the housing, but the second partitioning member may be, for example, a cylindrical member with a bottom, the opening of which may be fixed to the valve body in a sealed manner. In other words, the second partitioning member may be any member that defines an independent internal space that communicates with one of the spaces.

[0110] Furthermore, in the first and second embodiments, a solenoid is used as a drive source for moving the valve element, but a drive source other than a solenoid may be used to move the valve element.

[0111] Furthermore, in the first and second embodiments, the valve is a displacement control valve, but it may be, for example, an expansion valve disposed between a condenser and an evaporator in an air conditioning system. [Explanation of symbols]

[0112] 10 Valve housing 15 Through hole (communication means) 20 Rod (valve body) 30 First bellows (first compartment member) 31 Torso 40a CS valve seat (valve seat) 50 CS valve (valve) 51 CS valve body (valve body) 56 Valve body 57 Through hole (another means of communication) 60 Second bellows (second compartment member) 80 Solenoid (drive source) 100 Valve Housing 300 First bellows (first compartment member) 400a CS valve seat (valve seat) 510 CS valve body (valve body) 530 Sphere (Valve) 600 Second Bellows A~C Effective pressure area R1 1st connecting passage R2 Second communication passage (another communication means) S1,S1' Primary pressure space S2,S2' Secondary pressure space S3,S3' Back space S4, S4' internal space V1, V2 capacity control valve

Claims

1. A solenoid having a movable iron core, a fixed iron core, and a rod and a coil inserted into a through hole of the fixed iron core; a valve housing having a primary pressure space and a secondary pressure space; a valve seat disposed between the primary pressure space and the secondary pressure space; a valve body that is driven in the axial direction by a rod of the solenoid and is seated on or separated from the valve seat; A valve including a back space adjacent to one of the primary pressure space and the secondary pressure space, and a communication means for communicating the other of the primary pressure space and the secondary pressure space, a first partition member and a second partition member that are extendable and contractible in an axial direction are disposed between the valve housing and the valve body; the first partitioning member has a body portion including a ring member through which a portion of the rod is inserted and which is fixed to the valve housing, and a bellows which is hermetically fixed to the ring member, and which hermetically partitions the one space and the back space, the second partitioning member is hermetically fixed to the valve body and hermetically partitions an independent internal space within the other space, the internal space is in communication with the one space via another communication means, A valve in which the gap between the outer peripheral surface of the rod and the inner peripheral surface of the ring member is smaller than the gap between the outer peripheral surface of the rod and the inner peripheral surface of the insertion hole of the fixed iron core.

2. 2. The valve according to claim 1, wherein the effective pressure-receiving area of ​​the first partition member is smaller than the effective pressure-receiving area of ​​the second partition member.

3. 3. The valve according to claim 1, wherein the sum of the effective pressure-receiving area of ​​the first partition member and the effective pressure-receiving area of ​​the second partition member is equal to the effective pressure-receiving area of ​​the valve body.

4. 4. The valve according to claim 1, wherein the other communication means is a through hole extending through the valve body.

5. 4. The valve according to claim 1, wherein the other communication means is a communication passage that communicates the one space with the internal space outside the valve housing.

6. 6. The valve according to claim 1, wherein the first partition member and the second partition member are bellows having a bellows-shaped body portion.

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