Valve

Abstract

To provide a valve capable of preventing liquid from leaking outside.SOLUTION: A valve V1 for a scroll compressor C has a pressure receiving body 72 on which a suction pressure acts, a pressure receiving body 71 on which a discharge pressure acts, and a pressure receiving body 73 on which a control pressure acts, where the pressure receiving bodies 72, 73 have a pressure receiving surface B using a flexible material 75 or a pressure receiving surface C using a flexible material 77, and a space S5 defined by the flexible materials 75, 77 is sealed against outside air.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to valves, for example valves for regulating the flow rate of a fluid. [Background technology]

[0002] 2. Description of the Related Art Scroll compressors are one type of compressor used in various industrial fields. This type of compressor is not only highly efficient but also quiet, and therefore is used in a wide range of applications, such as in refrigeration cycles.

[0003] The scroll compressor is equipped with a scroll compression mechanism consisting of a fixed scroll with a spiral wrap and a movable scroll with a spiral wrap, and an eccentric mechanism that is attached to a rotating shaft and rotates the movable scroll eccentrically.The movable scroll slides relative to the fixed scroll while rotating eccentrically, thereby pressurizing a refrigerant fluid supplied from low-pressure chambers on the outer diameter sides of both scrolls, and discharging the high-pressure refrigerant from a discharge hole formed in the center of the fixed scroll.

[0004] In this type of scroll compressor, when the pressure in the discharge chamber, from which the refrigerant compressed by the scroll compression mechanism is discharged, increases, a force acts in a direction that separates the movable scroll from the fixed scroll.

[0005] In view of this, scroll compressors are known in which a portion of the refrigerant discharged into the discharge chamber is supplied to a back pressure chamber provided on the back side of the movable scroll to press the movable scroll toward the fixed scroll, thereby preventing the two from separating. Some of these scroll compressors are designed to prevent the movable scroll from being excessively pressed against the fixed scroll by discharging a portion of the refrigerant in the back pressure chamber into a low pressure chamber, thereby maintaining smooth operation of the movable scroll. Some of these scroll compressors use a valve to adjust the pressure in the back pressure chamber.

[0006] For example, the valve of Patent Document 1, which is installed in a scroll compressor, has a closing member segment on which suction pressure (Ps) acts, a closing member segment on which high pressure (Pd) acts, and a closing member segment on which counter pressure (Pb) acts.

[0007] The closure member segment on which suction pressure (Ps) acts and the closure member segment on which counter pressure (Pb) acts are connected to the membrane housing via rubber with the gaps sealed. The space between them is connected to an ambient pressure fluid connection, allowing the atmosphere to flow in and out. The closure member segment on which suction pressure (Ps) acts and the closure member segment on which counter pressure (Pb) acts are abutted by a force exerted in the direction of approaching each other, so the abutting state is maintained.

[0008] Depending on the balance between the force generated by the suction pressure (Ps) acting on the pressure-receiving surface of the closure member segment, the force generated by the high pressure (Pd) acting on the pressure-receiving surface of the closure member segment, the spring force of the spring member, and the force generated by the back pressure (Pb) acting on the pressure-receiving surface of the closure member segment, the closure member segment on which the high pressure (Pd) acts moves in the opening or closing direction to adjust the valve opening, and the amount of fluid flowing from the high pressure fluid connection to the back pressure fluid connection can be adjusted. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2018-536110 A (page 9, figure 4) Summary of the Invention [Problem to be solved by the invention]

[0010] However, the fluid compressed by the scroll compressor may be one that may be environmentally hazardous, and it is essential for such scroll compressors to prevent leakage of the fluid to the outside. However, the valve of Patent Document 1 has a problem in that the fluid leaks to the outside through the ambient pressure fluid connection when the rubber deteriorates with age or is damaged by other objects.

[0011] The present invention has been made in view of the above-mentioned problems, and has an object to provide a valve capable of preventing fluid from leaking to the outside. [Means for solving the problem]

[0012] In order to solve the above problems, the valve of the present invention comprises: A valve for a scroll compressor, comprising a pressure receiving body on which a suction pressure acts, a pressure receiving body on which a discharge pressure acts, and a pressure receiving body on which a control pressure acts, At least one of the pressure receiving bodies has a pressure receiving surface using a flexible material, The space defined by the flexible material is sealed against the outside air. This makes it possible to prevent fluid from leaking out even if the flexible material is damaged. In addition, the inflow of outside air into the space is prevented, so the elasticity of the flexible material does not change due to changes in the outside air temperature, and the operation of the pressure receiving body using the flexible material can be stabilized. Furthermore, outside air containing moisture does not enter the space, and ice is prevented from forming in the space, so the elastic deformation of the flexible material is smooth.

[0013] The two pressure receiving bodies may each have a pressure receiving surface using the flexible material, and the space may be between the two pressure receiving bodies. According to this, a space can be formed by the two pressure receiving bodies, so that the structure of the valve can be simplified.

[0014] The space may be a vacuum. According to this, even if the temperatures of the fluids in the chambers on both sides of the space are different, it is possible to reduce the heat transfer between the fluids at different temperatures.

[0015] The space may be filled with a fluid. According to this, the operating characteristics of the pressure-receiving body using flexibility can be adjusted by the pressure of the fluid sealed in the space. Also, the space can be easily maintained.

[0016] An internal pressure adjusting means for adjusting the pressure in the space may be provided. This allows the pressure in the space to be kept substantially constant, and the operation of the pressure-receiving body that utilizes its flexibility can be stabilized.

[0017] In the present invention, the vacuum state refers to "a state of space filled with gas at a pressure lower than normal atmospheric pressure" as defined by the Japanese Industrial Standards (JIS Z 8126). [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic configuration diagram showing a scroll compressor to which a valve according to a first embodiment of the present invention is applied. [Diagram 2] FIG. 1 is a cross-sectional view of a valve according to a first embodiment of the present invention. [Diagram 3] FIG. 6 is a cross-sectional view of a valve according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A valve according to the present invention will be described below with reference to the accompanying drawings. EXAMPLES

[0020] A valve according to a first embodiment will be described with reference to Figures 1 and 2. The valve of the present invention is applied to a rotary machine including an eccentric mechanism, for example, a scroll compressor C that sucks, compresses, and discharges a refrigerant as a fluid used in an air conditioning system of an automobile, etc. In this embodiment, the refrigerant is a gas mixed with mist-like lubricating oil.

[0021] First, a description will be given of the scroll compressor C. As shown in Fig. 1, the scroll compressor C is mainly composed of a housing 1, a rotating shaft 2, an inner casing 3, a scroll compression mechanism 4, a side seal 7, a thrust plate 8, and a drive motor M.

[0022] The housing 1 is composed of a cylindrical casing 11 and a cover 12 that closes an opening of the casing 11. An opening in the casing 11 on the axially opposite side to the opening closed by the cover 12 is closed by a drive motor M.

[0023] Inside the casing 11, there are formed a low pressure chamber 20 to which low pressure refrigerant, i.e., suction fluid Ps, is supplied from a refrigerant circuit (not shown) through the suction port 10, a high pressure chamber 30 serving as a discharge chamber from which high pressure refrigerant compressed by the scroll compression mechanism 4, i.e., discharge fluid Pd, is discharged, and a back pressure chamber 50 to which a part of the refrigerant compressed by the scroll compression mechanism 4 together with lubricating oil, i.e., control fluid Pb, is supplied via a flow rate control valve V1. The back pressure chamber 50 is formed inside a cylindrical inner casing 3 housed inside the casing 11.

[0024] A discharge communication passage 13 is formed in the cover 12, which communicates between a refrigerant circuit (not shown) and the high pressure chamber 30. A back pressure communication passage 14 is also formed in the cover 12, which communicates between the high pressure chamber 30 and the back pressure chamber 50 and branches off from the discharge communication passage 13. An oil separator 6 is provided in the discharge communication passage 13 to separate lubricating oil from the refrigerant.

[0025] The inner casing 3 is fixed with its axial end abutting against an end plate 41a of a fixed scroll 41 that constitutes the scroll compression mechanism 4. A suction communication passage 15 that penetrates radially is formed in the side wall of the inner casing 3. That is, the low pressure chamber 20 is formed from the outside of the inner casing 3 to the inside of the inner casing 3 via the suction communication passage 15. The suction fluid Ps supplied to the inside of the inner casing 3 through the suction communication passage 15 is sucked into the scroll compression mechanism 4.

[0026] The scroll compression mechanism 4 is mainly composed of a fixed scroll 41 that is fixed in a sealed manner to the cover 12 , and a movable scroll 42 that is housed inside the inner casing 3 .

[0027] The fixed scroll 41 is made of metal and has a spiral wrap 41b that protrudes from the surface of a disk-shaped end plate 41a, i.e., the end face of the end plate 41a that faces the movable scroll 42, towards the movable scroll 42. The fixed scroll 41 also has a recess 41c that is recessed in the opposite direction to the cover 12 on the inner diameter side of the back surface of the end plate 41a, i.e., the end face of the end plate 41a that abuts against the cover 12, and the high pressure chamber 30 is defined by this recess 41c and the cover 12.

[0028] The movable scroll 42 is made of metal and has a spiral wrap 42b that protrudes from the surface of a disk-shaped end plate 42a, i.e., the end face of the end plate 42a that faces the fixed scroll 41, toward the fixed scroll 41. The movable scroll 42 also has a boss 42c that protrudes from the center of the back surface of the end plate 42a. An eccentric portion 2a formed on the rotating shaft 2 is inserted into the boss 42c so as to be rotatable relative to the boss 42c. In this embodiment, the eccentric portion 2a of the rotating shaft 2 and the counterweight portion 2b that protrudes radially outward from the rotating shaft 2 form an eccentric mechanism that eccentrically rotates the rotating shaft 2.

[0029] When the rotary shaft 2 is driven to rotate by the drive motor M, the eccentric portion 2a rotates eccentrically, and the movable scroll 42 slides relative to the fixed scroll 41 while maintaining its posture with the eccentric rotation. At this time, the movable scroll 42 rotates eccentrically with respect to the fixed scroll 41, and with this rotation, the contact position of the wraps 41b, 42b moves sequentially in the rotation direction, and the compression chamber 40 formed between the wraps 41b, 42b moves toward the center and gradually shrinks. As a result, the intake fluid Ps sucked from the low pressure chamber 20 formed on the outer diameter side of the scroll compression mechanism 4 to the compression chamber 40 is compressed, and finally, a high-pressure discharge fluid Pd is discharged to the high pressure chamber 30 through the discharge hole 41d provided in the center of the fixed scroll 41.

[0030] The side seal 7 is made of resin, has a rectangular cross section and an annular shape when viewed in the axial direction, and is fixed to the back surface of the end plate 42a of the movable scroll 42. The side seal 7 is formed with a sliding surface 7a that comes into contact with a sliding surface 8a formed on the thrust plate 8.

[0031] The thrust plate 8 is made of metal, has an annular shape, and has a seal ring 43 fixed thereto. The seal ring 43 abuts against the inner peripheral end surface of the inner casing 3. As a result, the thrust plate 8 functions as a thrust bearing that receives the axial load of the movable scroll 42 via the side seal 7.

[0032] Additionally, the side seal 7 and the seal ring 43 divide the inside of the inner casing 3 into a low pressure chamber 20 formed on the outer diameter side of the movable scroll 42 and a back pressure chamber 50 formed on the back side of the movable scroll 42. The back pressure chamber 50 is formed as an enclosed space by a seal ring 44 fixed to the inner periphery of a through hole 3a provided in the center of the inner casing 3, sealing between the back pressure chamber 50 and the rotating shaft 2 inserted through the through hole 3a.

[0033] Further, a flow rate control valve V1 is provided as a valve in a back pressure communication passage 14 that is formed across the cover 12, the fixed scroll 41, and the inner casing 3 and communicates between the high pressure chamber 30 and the back pressure chamber 50. In other words, the flow rate control valve V1 is provided inside the housing 1 that is isolated from the outside air.

[0034] A part of the discharge fluid Pd from the high pressure chamber 30 that is supplied to the flow rate regulating valve V1 together with the lubricating oil separated by the oil separator 6 is adjusted in pressure to a control fluid Pb and is supplied to the back pressure chamber 50.

[0035] The inner casing 3 is provided with a pressure relief hole 16 that penetrates radially and connects the low pressure chamber 20 and the back pressure chamber 50, and an orifice 45 is provided within the pressure relief hole 16.

[0036] Next, the flow rate adjustment valve V1 as a valve in this embodiment will be described with reference to Fig. 2. In the following description, the left and right sides as viewed from the front side of Fig. 2 are the left and right sides of the flow rate adjustment valve V1.

[0037] As shown in FIG. 2, the flow control valve V1 of this embodiment 1 is mainly composed of a housing 60, a first pressure receiving body 71, a second pressure receiving body 72, a third pressure receiving body 73, and a coil spring 80 as a biasing means.

[0038] The housing 60, together with the three pressure receiving bodies 71, 72, 73, etc., defines a first space S1 communicating with the low pressure chamber 20, a second space S2 communicating with the high pressure chamber 30, a third space S3 and a fourth space S4 communicating with the back pressure chamber 50, and a fifth space S5 as the space of the present invention sandwiched between the second pressure receiving body 72 and the third pressure receiving body 73.

[0039] The housing 60 is composed of a first divided body 61, a second divided body 62, and a third divided body 63, in that order from the right side.

[0040] The first divided body 61 is formed in a cylindrical shape having a left large diameter recess 61a, a left small diameter recess 61b, a through hole 61c, and a right recess 61d on its inner diameter side. The axial centers of the left large diameter recess 61a, the left small diameter recess 61b, the through hole 61c, and the right recess 61d substantially coincide with the axial center of the first divided body 61.

[0041] The left large diameter recess 61a is recessed rightward from the left end face of the first divided body 61 and is open toward the left.

[0042] The left small diameter recess 61b is recessed rightward from the bottom surface of the left large diameter recess 61a, i.e., from a side surface extending in a direction substantially perpendicular to the axis of the left large diameter recess 61a, and is open toward the left. The left small diameter recess 61b has an inner diameter smaller than that of the left large diameter recess 61a, and is connected to the left large diameter recess 61a.

[0043] The through hole 61c axially penetrates the bottom surface of the left small diameter recess 61b. The through hole 61c has an inner diameter smaller than that of the left small diameter recess 61b and communicates with the left small diameter recess 61b and the right recess 61d.

[0044] The right recess 61d is recessed leftward from the right end face of the first divided body 61 and is open toward the right. The right recess 61d has an inner diameter larger than the inner diameter of the through hole 61c. The right recess 61d, together with the third pressure-receiving body 73, defines a fourth space S4.

[0045] The second divided body 62 is formed in a cylindrical shape having a left large diameter recess 62a, a left small diameter recess 62b, a through hole 62c, a right large diameter recess 62d, and a right small diameter recess 62e on its inner diameter side. The axial centers of the left large diameter recess 62a, the left small diameter recess 62b, the through hole 62c, the right large diameter recess 62d, and the right small diameter recess 62e substantially coincide with the axial center of the second divided body 62.

[0046] The left large diameter recess 62a is recessed rightward from the left end face of the second divided body 62 and is open toward the left.

[0047] The left small diameter recess 62b is recessed rightward from the bottom surface of the left large diameter recess 62a and is open toward the left. The left small diameter recess 62b has an inner diameter smaller than that of the left large diameter recess 62a and is connected to the left large diameter recess 62a.

[0048] The through hole 62c axially penetrates the bottom surface of the left small diameter recess 62b. The through hole 62c has an inner diameter smaller than the inner diameter of the left small diameter recess 62b and communicates with the left small diameter recess 62b and the right small diameter recess 62e.

[0049] The right large diameter recess 62d is recessed leftward from the right end face of the second divided body 62 and is open toward the right.

[0050] The right small diameter recess 62e is recessed leftward from the bottom surface of the right large diameter recess 62d, i.e., from the side surface extending in a direction substantially perpendicular to the axis of the right large diameter recess 62d, and is open toward the right. The right small diameter recess 62e has an inner diameter smaller than that of the right large diameter recess 62d and larger than that of the through hole 62c, and is connected to the right large diameter recess 62d.

[0051] The second divided body 62 has a communication passage 62f that radially penetrates the peripheral wall at the left end portion thereof and communicates with the left small diameter recess 62b. In this embodiment, the communication passages 62f are equally spaced in two, but the number and arrangement of the communication passages 62f may be changed as appropriate.

[0052] The second divided body 62 has a communication groove 62g that penetrates the peripheral wall at the right end in the radial direction and is open to the right. In this embodiment, there is only one communication groove 62g, but the number and arrangement of the communication grooves 62g may be changed as appropriate.

[0053] The second divided body 62 has a right end portion fitted and fixed in the left large diameter recess 61a of the first divided body 61. The right large diameter recess 62d and the right small diameter recess 62e of the second divided body 62 and the left large diameter recess 61a and the left small diameter recess 61b of the first divided body 61, together with the first pressure-receiving body 71 and the second pressure-receiving body 72, define a first space S1.

[0054] A slit 64 is left between the left end of the first divided body 61 and an annular protrusion formed on the left side of the right end face of the second divided body 62 and extending in the outer radial direction.

[0055] The communication groove 62 g communicates with the low pressure chamber 20 through a slit 64 .

[0056] The third divided body 63 is formed in a cylindrical shape having a left recess 63a, a valve hole 63b, and a right recess 63c on its inner diameter side. The axial centers of the left recess 63a, the valve hole 63b, and the right recess 63c substantially coincide with the axial center of the third divided body 63.

[0057] The left recess 63a is recessed rightward from the left end face of the third divided body 63 and is open toward the left. The left recess 63a defines a second space S2 together with the first pressure receiving body 71. The second space S2 is in communication with the high pressure chamber 30.

[0058] The valve hole 63b axially penetrates the bottom surface of the left recess 63a. The valve hole 63b has an inner diameter smaller than the inner diameter of the left recess 63a and communicates with the right recess 63c.

[0059] The right recess 63c is recessed leftward from the right end face of the third division body 63 and is open toward the right. The inside diameter of the right recess 63c is larger than the inside diameter of the valve hole 63b.

[0060] Further, the third divided body 63 has a valve seat 65 formed at a corner where an inner peripheral surface of the third divided body 63 at the valve hole 63b intersects with a bottom surface of the right recess 63c extending in a direction substantially perpendicular to the axis. The valve seat 65 constitutes a valve 70 together with a first pressure receiving body 71. In other words, the first pressure receiving body 71 is the valve body in this embodiment. The valve body may be provided separately from the first pressure receiving body and configured to move in response to the first pressure receiving body.

[0061] The third divided body 63 has a right end portion fitted and fixed in the left large diameter recess 62a of the second divided body 62. The right recess 63c of the third divided body 63 and the left large diameter recess 62a and the left small diameter recess 62b of the second divided body 62, together with the first pressure-receiving body 71, define a third space S3.

[0062] A slit 66 is left between the right end of the third split body 63 and the left large diameter recess 62a. The communication passage 62f in the second split body 62 communicates with the second space S2 through the slit 66. The communication passage 62f also communicates with the back pressure chamber 50.

[0063] The first pressure receiving body 71 is formed in a stepped cylindrical shape having, from the left, a tapered portion 71a, a large diameter body portion 71b, a small diameter body portion 71c, and a circular plate portion 71d.

[0064] The tapered portion 71a is tapered and has a diameter that increases toward the right in the axial direction. A part of the tapered portion 71a is inserted into the valve hole 63b in the third divided body 63. The opening degree of the valve 70 is changed by moving the tapered portion 71a toward and away from the valve seat 65. The effective pressure-receiving surface A1 of the first pressure-receiving body 71 is approximately the same as the flow passage cross section of the valve seat 65.

[0065] The large diameter body 71b has approximately the same diameter as the right end of the tapered portion 71a and extends axially to the right from this right end. The large diameter body 71b is inserted into the through hole 62c in the second divided body 62 and is disposed across the first space S1 and the third space S3. The effective pressure receiving surface between the first space S1 and the third space S3 is designated as D1.

[0066] Additionally, the large diameter body portion 71b is inserted into an O-ring 81. This O-ring 81, together with a part of the large diameter body portion 71b, is disposed in the left small diameter recess 62b of the second divided body 62. The O-ring 81 seals the space between the first space S1 and the third space S3 while allowing the first pressure-receiving body 71 to move in the axial direction.

[0067] The small diameter body portion 71c is tapered from the right end of the large diameter body portion 71b toward the right in the axial direction, and then extends to the right in the axial direction with approximately the same diameter. The right end of the small diameter body portion 71c is curved in the outer diameter direction toward the right in the axial direction and is continuous with the circular plate portion 71d.

[0068] The circular plate portion 71d is formed in a circular plate shape that protrudes radially outward from the small diameter body portion 71c. The maximum diameter of the circular plate portion 71d is smaller than the inner diameter of the right small diameter recess 62e of the second division body 62.

[0069] The left end surface of the circular plate portion 71d is a flat surface extending in a direction substantially perpendicular to the axis of the first pressure receiving body 71. This left end surface and the bottom surface of the right small diameter recess 62e are arranged opposite each other, and a coil spring 80 is arranged in a compressed state between them.

[0070] The right end surface of the circular plate portion 71d is a curved surface 71e that is curved so as to protrude inwardly as it goes axially rightward. The effective pressure receiving surface of the curved surface 71e is designated as E1.

[0071] The second pressure receiving body 72 is composed of a base material 74 and a flexible material 75 .

[0072] The substrate 74 is formed in a stepped cylindrical shape having, in order from the left, a left convex portion 74a, a base portion 74b, and a right convex portion 74c.

[0073] The left protrusion 74a is a disk-like member that protrudes leftward from the radial center of the left end face of the base 74b. A left end face 74d of the left protrusion 74a is a flat surface that extends in a direction substantially perpendicular to the axis of the substrate 74.

[0074] The base portion 74b has a cylindrical shape extending in the axial direction. The diameter of the base portion 74b is larger than the diameters of the left convex portion 74a and the right convex portion 74c.

[0075] The right protrusion 74c is a disk-like member that protrudes rightward from the center of the right end surface of the base 74b in the radial direction.

[0076] The flexible member 75 is a ring-shaped elastic member made of elastomer. The flexible member 75 is fitted onto the base material 74 and fixed with an adhesive. The flexible member 75 is also fitted into the left small diameter recess 61b of the first divided body 61 and fixed with an adhesive. The flexible member 75 seals the gap between the base material 74 and the first divided body 61. The flexible member 75 may be fixed to the base material 74 or the first divided body 61 with a material other than an adhesive.

[0077] In addition, the flexible material 75 has a base 75a sandwiched between the first divided body 61 and the base 74b, and the axial thickness of the base 75a becomes thinner toward the center in the radial direction. When a force is applied in the axial direction of the first divided body 61, the flexible material 75 elastically deforms so that the thin portion curves to the right or left in the axial direction. Note that the thin portion may have a constant thickness.

[0078] The effective pressure receiving surface B1 of the second pressure receiving body 72 is approximately the same as the area from the thinnest part on one radial side of the base portion 75a to the thinnest part on the other radial side.

[0079] The flexible member 75 also has an inner diameter side protrusion extending inward from the inner diameter side of the right end of the base portion 75b. An inner diameter end 75d of the inner diameter side protrusion bulges axially to the right and is in contact with the left convex portion 76a of the third pressure receiving body 73 together with the right convex portion 74c.

[0080] The third pressure receiving body 73 is composed of a base material 76 and a flexible material 77 .

[0081] The base material 76 is formed in a stepped cylindrical shape having, in order from the left, a left convex portion 76a, a base portion 76b, and a right stepped convex portion 76c.

[0082] The left convex portion 76a is a disk shape that protrudes leftward from the radial center of the left end face of the base portion 76b. A left end face 76d of the left convex portion 76a is a flat surface that extends in a direction substantially perpendicular to the axis of the base material 76. The diameter of the left convex portion 76a is smaller than the diameter of the left convex portion 74a of the second pressure receiving body 72.

[0083] The base 76b is cylindrical and extends in the axial direction. The diameter of the base 76b is larger than the diameters of the left convex portion 76a and the right stepped convex portion 76c. The diameter of the base 76b is smaller than the diameter of the base 74b of the second pressure receiving body 72.

[0084] The right stepped protrusion 76c has a stepped cylindrical shape that protrudes to the right from the radial center of the right end face of the base 76b.

[0085] The flexible member 77 is an annular elastic member made of elastomer. The outer diameter of the flexible member 77 is smaller than the outer diameter of the flexible member 75 in the second pressure receiving body 72. The flexible member 77 is fitted over the left convex portion 76a, the base portion 76b, and the large diameter portion of the right stepped convex portion 76c in the base material 76, and is fixed with an adhesive. The flexible member 77 is fitted over the inner circumferential surface of the first divided body 61 at the through hole 61c, and is fixed with an adhesive. The flexible member 77 seals the gap between the base material 76 and the first divided body 61. The flexible member 77 may be fixed to the base material 76 or the first divided body 61 by a method other than an adhesive.

[0086] In addition, the flexible material 77 has a base 77a sandwiched between the first divided body 61 and the base 76b, and the axial thickness of the base 77a becomes thinner toward the center in the radial direction. When a force is applied in the axial direction of the first divided body 61, the flexible material 75 elastically deforms such that the thin portion curves to the right or left in the axial direction. Note that the thin portion may have a constant thickness.

[0087] The effective pressure receiving surface C1 of the third pressure receiving body 73 is approximately the same as the area from the thinnest part on one radial side of the base portion 77a to the thinnest part on the other radial side. The area of ​​the effective pressure receiving surface C1 is smaller than the area of ​​the effective pressure receiving surface B1 and is larger than the area of ​​the effective pressure receiving surface A1 (A1 <C1<B1)。

[0088] The second pressure receiving body 72 and the third pressure receiving body 73 are attached to the first divided body 61 before the first divided body 61 is attached to the second divided body 62 .

[0089] First, the first divided body 61, the second pressure receiving body 72, and the third pressure receiving body 73 are housed in a case and the inside is made a vacuum. Then, the second pressure receiving body 72 and the third pressure receiving body 73 are fitted and fixed inside the first divided body 61. As a result, the fifth space S5 sandwiched between the second pressure receiving body 72 and the third pressure receiving body 73 becomes a vacuum.

[0090] In order to evacuate the fifth space S5, the vacuum may be drawn through a through hole provided in the first divided body 61, and then the through hole may be closed, or the method for doing so may be changed as appropriate.

[0091] In this way, since the configuration on the first divided body 61 side can be assembled separately from the configurations on the second divided body 62 and third divided body 63 sides, it is easy to evacuate the fifth space S5.

[0092] When the second pressure receiving body 72 and the third pressure receiving body 73 are fitted and fixed inside the first divided body 61, the right convex portion 74c of the second pressure receiving body 72 and the left convex portion 76a of the third pressure receiving body 73 are brought into contact with each other.

[0093] Next, the opening and closing operation of the flow rate regulating valve V1 will be described. In the housing 60, the intake fluid Ps flows into the first space S1, the discharge fluid Pd flows into the second space S2, and the control fluid Pb flows into the third space S3 and the fourth space S4.

[0094] The first pressure receiving body 71 is a pressure receiving body that receives a force (F Pd= Pd × area of ​​effective pressure receiving surface A1) and the force (F Pb1 = Pb × (area of ​​effective pressure receiving surface D1 - area of ​​effective pressure receiving surface A1)) and the force (F Ps1 = Ps × (area of ​​effective pressure receiving surface E1 - area of ​​effective pressure receiving surface D1)) and the biasing force of the coil spring 80 (F b ) is pushed to the right in the axial direction (i.e., the rightward direction is positive, and the first pressure receiving body 71 is subjected to a force F1=F Pd +F Pb1 +F Ps1 +F b is at work).

[0095] The first pressure body 71 follows the force F1 even when the flexible material 75 in the second pressure body 72 elastically deforms and the base material 74 in the second pressure body 72 moves all the way to the right in the axial direction, so that the curved surface 71e of the first pressure body 71 and the left end face 74d of the second pressure body 72 are maintained in contact with each other.

[0096] The second pressure receiving body 72 is resistant to the force (F Ps2 = Ps × (area of ​​effective pressure receiving surface B1 - area of ​​effective pressure receiving surface E1)), the pressure in the fifth space S5 acts on the effective pressure receiving surface B1, and the force generated pushes the second pressure receiving body 72 to the right in the axial direction. In this embodiment, since the fifth space S5 is a vacuum, the internal pressure is considered to be zero (i.e., the rightward direction is considered to be positive, and the second pressure receiving body 72 is subjected to a force F2 = F Ps2 is at work).

[0097] The third pressure receiving body 73 is a pressure receiving body that receives a force (F Pb2 = Pb × area of ​​the effective pressure receiving surface C1), and the third pressure receiving body 73 is pushed to the left in the axial direction by the force generated when the pressure in the fifth space S5 acts on the effective pressure receiving surface B1 (that is, the leftward direction is positive, and the third pressure receiving body 73 is subjected to a force F3 = F Pb2 is at work).

[0098] That is, the force F2 acting on the second pressure receiving body 72 and the force F3 acting on the third pressure receiving body 73 are opposed to each other. Therefore, the right side protrusion 74c of the second pressure receiving body 72 and the left side protrusion 76a of the third pressure receiving body 73 are kept in contact with each other.

[0099] When the sum of forces F1 and F2 of the first pressure body 71, the second pressure body 72, and the third pressure body 73 exceeds force F3, the first pressure body 71 and the base materials 74, 76 move toward the right in the axial direction while elastically deforming each flexible material 75, 77 toward the right in the axial direction (force F1 + force F2 > force F3).

[0100] In addition, when the sum of forces F1 and F2 falls below force F3, the first pressure body 71, the second pressure body 72, and the third pressure body 73 elastically deform each flexible material 75, 77 toward the left in the axial direction, while the first pressure body 71 and each base material 74, 76 move toward the left in the axial direction (force F1 + force F2 < force F3).

[0101] As described above, the flow rate regulating valve V1 is capable of adjusting the opening degree of the valve 70 by moving the first pressure receiving body 71 in the axial direction according to the balance between the sum of the forces F1 and F2 and the force F3.

[0102] Furthermore, when the flexible materials 75, 77 elastically deform in the axial direction, even if the volume of the fifth space S5 changes, the pressure in the fifth space S5, which is a vacuum, remains substantially constant, and therefore the elastic deformation of the flexible materials 75, 77 is not easily hindered. This makes it possible to stabilize the operation of the second pressure-receiving body 72 and the third pressure-receiving body 73.

[0103] As described above, the flow rate control valve V1 of this embodiment adjusts the opening of the valve 70 in accordance with the balance between the sum of the forces F1 and F2 and the force F3, and can reduce the pressure of the discharge fluid Pd to a pressure corresponding to the opening and supply it to the back pressure chamber 50. In this way, the flow rate control valve V1 can adjust the pressure of the control fluid Pb in accordance with the pressure of the suction fluid Ps, the pressure of the discharge fluid Pd, and the pressure of the control fluid Pb.

[0104] In addition, the flow control valve V1 has a fifth space S5 partitioned by the flexible material 75 in the second pressure receiving body 72 and the flexible material 77 in the third pressure receiving body 73, which is sealed against the outside air, so that even if the flexible materials 75, 77 are damaged, the refrigerant can be prevented from leaking to the outside.

[0105] In addition, the inflow of outside air into the fifth space S5 is prevented, the elasticity of the flexible materials 75, 77 does not change due to changes in the outside air temperature, and the operation of the second pressure body 72 and the third pressure body 73 can be stabilized.

[0106] Furthermore, moisture-containing outside air does not enter the fifth space S5, and ice is prevented from forming in the fifth space S5, so that the elastic deformation of the flexible members 75, 77 is smoothly performed.

[0107] Furthermore, since the fifth space S5 is formed by the second pressure receiving body 72 and the third pressure receiving body 73, the structure of the flow rate adjustment valve V1 can be simplified.

[0108] Furthermore, since the fifth space S5 is a vacuum, even if the temperature of the intake fluid Ps flowing into the first space S1 located on both sides of the fifth space S5 is different from the temperature of the control fluid Pb flowing into the fourth space S4, the heat transfer between the intake fluid Ps and the control fluid Pb can be reduced.

[0109] Moreover, the diameter of the large diameter body 71b of the first pressure receiving body 71 is slightly shorter than the inner diameter of the through hole 62c. Furthermore, the first pressure receiving body 71 is aligned along the axis of the second divided body 62 by the elastic force of the O-ring 81. As a result, the outer peripheral surface of the large diameter body 71b and the inner peripheral surface of the through hole 62c are less likely to come into sliding contact with each other when the first pressure receiving body 71 moves in the axial direction, and the generated frictional force is easily reduced.

[0110] Furthermore, since the curved surface 71e of the first pressure body 71 abuts the left end surface 74d of the second pressure body 72, even if the flexible material 75 elastically deforms to tilt relative to the axis of the first pressure body 71 due to factors such as the presence of an area where air bubbles are concentrated in the flexible material 75, and the first pressure body 71 is pressed diagonally relative to the axis, the first pressure body 71 can be easily moved along the axis.

[0111] Furthermore, even if the second pressure body 72 and the third pressure body 73 attempt to tilt relative to each other due to the relative movement of their respective base materials 74, 76, the tilting is likely to be reduced by the elastic force generated when a portion of the inner diameter end 75d of the flexible material 75 is pressed against the left side convex portion 76a of the third pressure body 73. EXAMPLES

[0112] Next, a valve according to a second embodiment will be described with reference to Fig. 3. Note that a description of the same configuration as in the previous embodiment will be omitted.

[0113] 3, the flow rate control valve V2 of the second embodiment has an internal pressure adjustment means 190 configured in the first divided body 161 of the housing 160. The internal pressure adjustment means 190 is configured from a through hole 161e that radially penetrates the peripheral wall of the first divided body 161 and communicates with the left small diameter recess 161b, and a membrane material 192 that closes the outer diameter end of the through hole 161e. The membrane material 192 is made of elastomer and is elastically deformable.

[0114] When assembling the second pressure receiving body 72 and the third pressure receiving body 73 to the first divided body 161, first, the second pressure receiving body 72 and the third pressure receiving body 73 are fitted and fixed inside the first divided body 161. Next, nitrogen is injected through the through hole 161e into the fifth space S15 between the second pressure receiving body 72 and the third pressure receiving body 73 to set the pressure inside the fifth space S15 to a predetermined pressure, and then the through hole 161e is closed with the membrane material 192 while maintaining the predetermined pressure.

[0115] As in the first embodiment, a predetermined pressure may be sealed in the fifth space S15 by assembling the second pressure body 72 and the third pressure body 73 to the first divided body 161 inside a case that is set to a predetermined pressure other than a vacuum.

[0116] The fluid injected into the fifth space S15 may be air or a refrigerant, that is, the type of fluid may be changed as appropriate. The fluid injected into the fifth space S15 may be in a gaseous or liquid state, and may be changed as appropriate. It is preferable that the fluid injected into the fifth space S15 does not change state whether the scroll compressor C is operating or not, and has a low dew point temperature.

[0117] With this configuration, the operating characteristics of the second pressure receiving body 72 and the third pressure receiving body 73 can be adjusted by the pressure of the fluid sealed in the fifth space S15. That is, by setting the pressure in the fifth space S15 high, the elastic deformation rate of each of the flexible materials 75, 77 can be adjusted to be small, and by setting the pressure in the fifth space S15 low, the elastic deformation rate of each of the flexible materials 75, 77 can be adjusted to be large.

[0118] In addition, the fifth space S15 is easily maintained by the pressure of the fluid sealed in the fifth space S15.

[0119] Furthermore, the membrane material 192 elastically deforms in response to the flexible materials 75, 77 elastically deforming in the axial direction, changing the volume of the fifth space S15 and causing the pressure in the fifth space S15 to change. As a result, the volume of the fifth space S15 is kept substantially the same as before the elastic deformation of the flexible materials 75, 77, and the pressure in the fifth space S15 is also kept substantially constant. This makes it possible to stabilize the operation of the second pressure receiving body 72 and the third pressure receiving body 73. This also applies when the pressure in the fifth space S15 is about to change due to other factors, such as thermal expansion or thermal contraction of the nitrogen in the fifth space S15.

[0120] In addition, the internal pressure adjustment means is not limited to a membrane material that blocks the through hole, but may be, for example, a piston that blocks the through hole and a spring that urges the piston toward the space, air pressure, or other resilient means, and may be modified as appropriate.

[0121] Furthermore, the membrane material is not limited to being provided in a through hole formed in the housing, but may be provided in a recess formed in the housing, and the location where it is provided may be changed as appropriate.

[0122] 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.

[0123] For example, in the first and second embodiments, the flow rate control valve is provided in the back pressure communication passage that communicates the high pressure chamber and the back pressure chamber, and the orifice is provided in the pressure relief hole that communicates the low pressure chamber and the back pressure chamber, but the present invention is not limited to this, and the orifice may be provided in the back pressure communication passage and the flow rate control valve may be provided in the pressure relief hole. In such a configuration, it is preferable that the control fluid Pb flows into the second space and the suction fluid Ps flows into the third space. In addition, the fluids that flow into the first space and the fourth space may be changed as appropriate regardless of where the flow rate control valve is disposed.

[0124] In addition, in the above-mentioned Examples 1 and 2, the pressure receiving surface of the discharged fluid is smaller than the pressure receiving surface of the control fluid, and the pressure receiving surface of the control fluid is smaller than the pressure receiving surface of the suction fluid. However, this is not limited to this, and the size relationship of each pressure receiving surface may be changed as appropriate, or may be the same.

[0125] In addition, in the above-mentioned Examples 1 and 2, a space sealed against the outside air is provided between the second pressure body and the third pressure body, but this is not limited to this, and a space sealed against the outside air may be provided between the C-shaped housing and one of the pressure bodies, or may be modified as appropriate.

[0126] Further, in the first and second embodiments, the biasing means is provided, but the present invention is not limited to this, and the biasing means may be omitted.

[0127] In addition, in the first and second embodiments, the biasing means is described as being a coil spring, but this is not limited thereto, and may be a coiled wave spring, a leaf spring, or any other suitable modification.

[0128] In addition, in the first and second embodiments, the biasing means is described as functioning as a compression spring, but the present invention is not limited to this and may be a tension spring.

[0129] In addition, in the first and second embodiments, the valve is applied to a scroll compressor used in an air conditioning system of an automobile or the like. However, the present invention is not limited to this, and the valve may be used to control various working fluids.

[0130] In addition, in the first and second embodiments, the valve is a flow control valve. However, the valve may be, for example, an expansion valve disposed between a condenser and an evaporator in an air conditioning system, or a displacement control valve incorporated in a variable displacement compressor in an air conditioning system.

[0131] Furthermore, the intake fluid, discharge fluid, and control fluid may each be in the form of gas, liquid, or a mixture of gas and liquid. [Explanation of symbols]

[0132] 60 Housing 65 Valve seat 70 Valves 71 First pressure receiving body (pressure receiving body) 72 Second pressure receiving body (pressure receiving body) 73 Third pressure body (pressure body) 75,77 Flexible material 80 Coil spring (biasing means) 81 O-ring 160 Housing 190 Internal pressure adjustment means A1 Effective pressure surface B1 Effective pressure surface (pressure surface) C1 Effective pressure surface (pressure surface) Pb Control Fluid Pd discharge fluid Ps suction fluid S5,S15 5th space (space) V1, V2 flow control valve (valve)

Claims

1. A valve for a scroll compressor, comprising a pressure receiving body on which a suction pressure acts, a pressure receiving body on which a discharge pressure acts, and a pressure receiving body on which a control pressure acts, At least one of the pressure receiving bodies has a pressure receiving surface using a flexible material, A valve in which the space defined by the flexible material is sealed against outside air.

2. 2. The valve according to claim 1, wherein the two pressure receiving bodies have pressure receiving surfaces using the flexible material, and the space is between the two pressure receiving bodies.

3. 3. The valve of claim 2, wherein the space is a vacuum.

4. 3. The valve of claim 2, wherein the space contains a fluid.

5. 5. A valve according to claim 4, further comprising an internal pressure adjusting means for adjusting the pressure in said space.

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