Expansion valve

Abstract

To provide an expansion valve that is simple in structure yet can perform its function as a component. [Solution] The expansion valve comprises a valve body, a valve element, an operating rod 5 which is partially positioned in the return passage, communication chamber, and discharge passage and contacts the valve element, and a sealing device 6 which is positioned in the communication chamber and seals the space between the discharge passage and the return passage. The sealing device 6 comprises an annular seal 61 which contacts the inner wall of the communication chamber along the operating rod 5 and the operating rod 5, and a retaining member 62 which is positioned between the seal 61 and the return passage side and fixed to the valve body, and has a hole 28 in which a part of the operating rod 5 is positioned, and which contacts the seal 61 to prevent the seal 61 from moving toward the return passage side and holds the seal 61 relative to the valve body. A space is formed between the seal 61, the inner wall of the communication chamber, and the retaining member 62, and the retaining member 62 of the sealing device 6 has a passage forming portion 62c which constitutes at least a part of a passage connecting the space to the return passage side from the retaining member 62 so that the refrigerant can pass through.

Description

Technical Field

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[0001] The present invention relates to an expansion valve.

Background Art

[0002] Conventionally, in a refrigeration cycle used in, for example, an air conditioner mounted on an automobile, a temperature-sensitive thermostatic expansion valve that adjusts the amount of refrigerant passing through according to temperature has been used. In such a thermostatic expansion valve, a power element that drives a valve body via an operating rod by the pressure of the enclosed working gas is employed.

[0003] In the expansion valve shown in Patent Document 1, the operating rod is arranged so as to pass through an outlet port that passes through a valve seat on which the valve body is seated, an inlet port into which refrigerant from an evaporator enters, and a central hole that connects the two ports. If refrigerant directly flows from the inlet port to the outlet port through the central hole, the amount of refrigerant passing through the evaporator may decrease, and the cooling efficiency may decrease. Therefore, by arranging an O-ring between a cylindrical valve seat constituent member disposed in the central hole and the operating rod, the movement of refrigerant between the two ports is restricted. Further, this O-ring is prevented from falling off by an annular member attached over the entire inner circumference of the valve seat constituent member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] <000Generally, refrigerants contain a predetermined amount of lubricant, which lubricates the sliding parts. In this case, the O-ring in Patent Document 1 receives pressure from the refrigerant, biased toward the inlet port due to the differential pressure between the outlet port and the inlet port. Therefore, the O-ring comes into contact with the surface of the annular member facing the O-ring, the outer surface of the operating rod, and the inner surface of the valve seat component. At this time, the annular space sandwiched between the surface of the annular member facing the O-ring, the inner surface of the valve seat component, and the surface of the O-ring is sealed from either the outlet port or the inlet port, making it difficult for refrigerant to enter the space. As a result, a lack of lubrication occurs in the O-ring facing this space, which may lead to twisting due to reduced sliding properties and deterioration of the O-ring itself, potentially reducing the sealing function.

[0006] Therefore, the present invention aims to provide an expansion valve that has a simple structure yet can perform the function of its components. [Means for solving the problem]

[0007] To achieve the above objective, the expansion valve according to the present invention is A valve body comprising: an exhaust passage through which refrigerant that has passed through an orifice passes; a return passage through which refrigerant discharged to the outside via the exhaust passage enters; and a communication chamber connecting the exhaust passage and the return passage. Valve body and, An operating rod is provided, which is partially located in the return passage, the communication chamber, and the discharge passage, and which contacts the valve body. It has a sealing device arranged in the communication chamber that seals the space between the discharge side passage and the return passage, The sealing device comprises an annular seal that abuts against the inner wall of the communication chamber along the operating rod and the operating rod, and a retaining member that is positioned between the seal and the return passage side and fixed to the valve body, has a hole in which a part of the operating rod is positioned, and abuts against the seal to prevent the seal from moving toward the return passage side and holds the seal relative to the valve body. A space is formed between the seal, the inner wall of the communication chamber, and the retaining member. The retaining member of the sealing device has a passage forming portion that constitutes at least a part of a passage connecting the return flow path side from the retaining member to the space, allowing the refrigerant to pass through. It is characterized by the following: [Effects of the Invention]

[0008] The present invention provides an expansion valve that can perform its function as a component despite having a simple structure. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic cross-sectional view illustrating an example in which the expansion valve in the first embodiment is applied to a refrigerant circulation system. [Figure 2] Figure 2 is a perspective view showing a portion of the expansion valve of this embodiment, cut away from the original. [Figure 3] Figure 3 is an enlarged cross-sectional view showing the sealing device of the first embodiment. [Figure 4] Figure 4 is a perspective view showing a retaining plate according to the first embodiment. [Figure 5] Figure 5 is a perspective view showing a retaining plate according to the second embodiment. [Figure 6] Figure 6 is a perspective view of the retaining plate according to the third embodiment, viewed from one side. [Figure 7] Figure 7 is a perspective view of the retaining plate according to the third embodiment, viewed from the other side. [Figure 8] Figure 8 is a cross-sectional view similar to Figure 3, showing a sealing device according to a third embodiment. [Figure 9] Figure 9 is a cross-sectional view similar to Figure 3, showing a sealing device according to a third embodiment. [Figure 10] Figure 10 is a cross-sectional view similar to Figure 3, showing a sealing device according to the fourth embodiment. [Figure 11] Figure 11 is a perspective view showing a retaining plate according to the fourth embodiment. [Figure 12]FIG. 12 is a perspective view of the pressing plate according to the fifth embodiment as viewed from one surface side. [Figure 13] FIG. 13 is a perspective view of the pressing plate according to the fifth embodiment as viewed from the other surface side. [Figure 14] FIG. 14 is a perspective view showing the pressing plate according to the sixth embodiment. [Figure 15] FIG. 15 is a cross-sectional view similar to FIG. 3 showing the sealing device according to the seventh embodiment. [Figure 16] FIG. 16 is a perspective view showing the pressing plate according to the seventh embodiment. [Figure 17] FIG. 17 is a perspective view showing the pressing plate according to the eighth embodiment. [Figure 18] FIG. 18 is a cross-sectional view similar to FIG. 3 showing the sealing device according to the ninth embodiment. [Figure 19] FIG. 19 is a perspective view showing the pressing plate according to the ninth embodiment. [Figure 20] FIG. 20 is a perspective view showing the pressing plate according to the tenth embodiment. [Figure 21] FIG. 21 is a perspective view showing the pressing plate according to the eleventh embodiment. [Figure 22] FIG. 22 is a cross-sectional view similar to FIG. 3 showing the sealing device according to the twelfth embodiment. [Figure 23] FIG. 23 is a perspective view of the pressing plate according to the twelfth embodiment as viewed from one side. [Figure 24] FIG. 24 is a perspective view of the pressing plate according to the twelfth embodiment as viewed from the other side. [Figure 25] FIG. 25 is a cross-sectional view similar to FIG. 3 showing the sealing device according to a modified example of the twelfth embodiment. [Figure 26] FIG. 26 is a cross-sectional view showing the sealing device according to a modified example of the twelfth embodiment and the surrounding structure partially cut away. [Figure 27] FIG. 27 is a cross-sectional view similar to FIG. 3 showing the sealing device according to the thirteenth embodiment. [Figure 28]Figure 28 is a perspective view of the retaining plate according to the 13th embodiment, viewed from one side. [Figure 29] Figure 29 is a perspective view of the retaining plate according to the 13th embodiment, seen from the other side. [Figure 30] Figure 30 is a cross-sectional view similar to Figure 3, showing a sealing device according to the 14th embodiment. [Figure 31] Figure 31 is a perspective view showing a retaining member according to the 14th embodiment. [Figure 32] Figure 32 is a perspective view showing a retaining member according to the 15th embodiment. [Figure 33] Figure 33 is a cross-sectional view similar to Figure 3, showing a sealing device according to the 16th embodiment. [Figure 34] Figure 34 is a perspective view showing a retaining member according to the 16th embodiment. [Figure 35] Figure 35 is a perspective view showing a retaining member according to the 17th embodiment. [Figure 36] Figure 36 is a cross-sectional view similar to Figure 3, showing a sealing device according to the 18th embodiment. [Figure 37] Figure 37 is a perspective view showing a retaining member according to the 18th embodiment. [Figure 38] Figure 38 is a perspective view showing a retaining member according to the 19th embodiment. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings.

[0011] (Definition of direction) In this specification, the direction from the valve body 3 toward the actuator rod 5 is defined as "upward," and the direction from the actuator rod 5 toward the valve body 3 is defined as "downward." Therefore, in this specification, regardless of the orientation of the expansion valve 1, the direction from the valve body 3 toward the actuator rod 5 is referred to as "upward." Also, "plan view" refers to viewing an object from above toward below.

[0012] (First Embodiment) The expansion valve 1 in the first embodiment will be described below. Figure 1 is a schematic cross-sectional view illustrating an example in which the expansion valve 1 in this embodiment is applied to a refrigerant circulation system 100. Figure 2 is a perspective view showing a part of the expansion valve 1 cut away. The center line of the operating rod 5 of the expansion valve 1 is defined as axis L.

[0013] In this embodiment, the expansion valve 1 is fluidly connected to the compressor 101, the condenser 102, and the evaporator 103.

[0014] In Figure 1, the expansion valve 1 comprises a valve body 2 having a valve chamber VC, a spherical valve body 3, a biasing device 4, an operating rod 5, a sealing device 6, and a power element 8.

[0015] The valve body 2 comprises a valve chamber VC, a first passage 21, a second passage 22, an intermediate chamber 221, and a return passage (also simply called a passage) 23. The first passage 21 is a supply-side passage, and refrigerant is supplied to the valve chamber VC via this passage. The second passage 22 and the intermediate chamber 221 are discharge-side passages, and the fluid in the valve chamber VC is discharged outside the expansion valve through the orifice hole 27 and the discharge-side passage.

[0016] The first flow path 21 and the valve chamber VC are connected by a smaller diameter connecting passage (also called an introduction passage) 21a than the first flow path 21. The valve chamber VC and the intermediate chamber 221 are connected via a valve seat 20 and an orifice hole 27 (collectively referred to as an orifice).

[0017] In the valve body 2, the operating rod insertion hole 28 formed above the intermediate chamber 221 has the function of guiding the operating rod 5, and the annular recess 29 formed above the operating rod insertion hole 28 has the function of housing the sealing device 6.

[0018] The valve body 3 is positioned within the valve chamber VC. When the valve body 3 is seated on the valve seat 20 of the valve body 2, the flow of refrigerant through the orifice hole 27 is restricted. This state is called the non-communication state. However, even when the valve body 3 is seated on the valve seat 20, a limited amount of refrigerant may still flow. On the other hand, as shown in Figure 1, when the valve body 3 is separated from the valve seat 20, the flow of refrigerant through the orifice hole 27 increases. This state is called the communication state.

[0019] The actuator rod 5 is partially positioned in the return passage 23, the annular recess 29, and the discharge passage, and is inserted through the orifice hole 27 with a predetermined gap. The lower end of the actuator rod 5 is in contact with the upper surface of the valve body 3. The actuator rod 5 passes through the actuator rod insertion hole 28, the annular recess 29, and the return passage 23, and the upper end of the actuator rod 5 is connected to a stopper member (not shown) of the power element 8.

[0020] The power element 8 has an internal structure in which a diaphragm is sandwiched between an upper cover member 82 and a receiving member 86, with a stopper member in contact with the lower surface of the diaphragm. The operating gas is injected into the sealed upper space formed by the upper cover member 82 and the diaphragm, and the sealed lower space formed by the receiving member 86 and the diaphragm is in communication with the return passage 23.

[0021] The actuator rod 5 can press the valve body 3 in the opening direction against the biasing force of the biasing device 4. When the actuator rod 5 moves downward, the valve body 3 separates from the valve seat 20, and the expansion valve 1 opens.

[0022] As shown in Figures 1 and 2, the biasing device 4 includes a coil spring 41 made by winding wire in a spiral shape, a valve body support 42, and a bottomed cylindrical spring receiving member 43.

[0023] The spring support member 43, which supports the lower end of the coil spring 41, is screwable onto the valve body 2 and has the function of sealing the valve chamber VC and adjusting the biasing force of the coil spring 41. An O-ring 44 with a sealing function is placed between the spring support member 43 and the valve body 2.

[0024] Figure 3 is a cross-sectional view showing an enlarged view of the sealing device 6. Figure 4 is a perspective view showing the retaining plate 62.

[0025] In Figure 3, the substantially cylindrical annular recess 29 has a bottom wall 29a extending radially outward from the upper end of the operating rod insertion hole 28, a small-diameter inner circumferential surface 29b extending axially upward from the radial outer edge of the bottom wall 29a, a tapered surface 29c connected to the upper end of the small-diameter inner circumferential surface 29b, an intermediate surface 29d extending radially outward from the upper end of the tapered surface 29c, a medium-diameter inner circumferential surface 29e with a circular cross-section extending axially upward from the radial outer side of the intermediate surface 29d, a recess periphery surface 29f extending radially outward from the upper end of the medium-diameter inner circumferential surface 29e, and a large-diameter inner circumferential surface 29g extending axially upward from the radial outer edge of the recess periphery surface 29f. The interior of the annular recess 29 forms a communication chamber connecting the return flow path 23 and the intermediate chamber 221, and the inner wall of the annular recess 29 is composed of a bottom wall 29a, a small-diameter inner surface 29b, a tapered surface 29c, an intermediate surface 29d, and a medium-diameter inner surface 29e.

[0026] The sealing device 6 includes an O-ring 61 as an annular seal and a retaining plate 62 as a retaining member that holds the O-ring 61 in the annular recess 29. As shown in Figure 4, the retaining plate 62 is formed into an annular flat plate by press molding, for example, a metal plate, and has a circular outer circumference 62a and a circular inner circumference 62b that are coaxial. The circular inner circumference 62b forms a hole through which a part of the operating rod 5 is inserted. The retaining plate 62 has the function of holding the O-ring 61 relative to the valve body 2 by contacting the O-ring 61 and preventing the O-ring 61 from moving toward the return passage 23. The retaining plate 62 also has a shape in which a part of the outer circumference 62a is cut out, and has a groove (passage forming part) 62c that extends radially from the outer circumference 62a toward the inner circumference 62b, with a part of it forming a passage for the refrigerant. The outer diameter of the outer circumference portion 62a is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference portion 62b is larger than the outer diameter of the operating rod 5. Preferably, the vertical length of the medium-diameter inner surface 29e is greater than the thickness of the retaining plate 62.

[0027] When assembling the sealing device 6, the O-ring 61 is placed in the annular recess 29, and the retaining plate 62 is inserted into the medium-diameter inner circumferential surface 29e, with its lower surface in contact with the intermediate surface 29d. In this state, the surrounding surface 29f of the recess around the medium-diameter inner circumferential surface 29e is struck with a tool to create a dent, thereby plastically deforming the medium-diameter inner circumferential surface 29e so that it protrudes radially inward. This causes the inner circumference of the medium-diameter inner circumferential surface 29e to adhere tightly to the outer circumference 62a of the retaining plate 62, preventing the retaining plate 62 from coming out of the annular recess 29. After that, the operating rod 5 is passed through the O-ring 61 and inserted into the operating rod insertion hole 28. The retaining plate 62 may also be press-fitted into the medium-diameter inner circumferential surface 29e.

[0028] (Operation of the expansion valve) Referring to Figure 1, an example of the operation of the expansion valve 1 will be explained. The refrigerant pressurized by the compressor 101 is liquefied in the condenser 102 and sent to the expansion valve 1. The refrigerant that has been adiabatically expanded in the expansion valve 1 is then sent to the evaporator 103, where it undergoes heat exchange with the air flowing around it. The refrigerant returning from the evaporator 103 is returned to the compressor 101 side through the expansion valve 1 (more specifically, the return passage 23). At this time, the fluid pressure in the return passage 23 is slightly lower than the fluid pressure in the second passage 22 after passing through the evaporator 103.

[0029] The expansion valve 1 is supplied with high-pressure refrigerant from the condenser 102. More specifically, the high-pressure refrigerant from the condenser 102 is supplied to the valve chamber VC via the first flow path 21.

[0030] When the valve body 3 is seated on the valve seat 20 (in a non-communicating state), the flow rate of refrigerant sent from the valve chamber VC to the evaporator 103 through the orifice hole 27, intermediate chamber 221, and second flow path 22 is limited. On the other hand, as shown in Figure 1, when the valve body 3 is separated from the valve seat 20 (in a communicative state), the flow rate of refrigerant sent from the valve chamber VC to the evaporator 103 through the orifice hole 27, intermediate chamber 221, and second flow path 22 increases. Switching between the closed and open states of the expansion valve 1 is performed by an operating rod 5 connected to the power element 8 via a stopper member 84.

[0031] In Figure 1, the power element 8 is provided with an upper space and a lower space separated by a diaphragm 83. Therefore, when the working gas in the upper space is liquefied, the diaphragm rises, causing the stopper member and the operating rod 5 to move upward in accordance with the biasing force of the coil spring 41.

[0032] On the other hand, when the liquefied working gas in the upper space vaporizes, the diaphragm and stopper member are pressed downwards, causing the working rod 5 to move downwards. As a result, the volume of the working gas in the upper space changes according to the temperature and pressure of the refrigerant flowing through the return passage 23, and the working rod 5 is driven. In other words, in the expansion valve 1 shown in Figure 1, the amount of refrigerant supplied from the expansion valve 1 to the evaporator 103 is automatically adjusted according to the temperature and pressure of the refrigerant returning from the evaporator 103 to the expansion valve 1.

[0033] The intermediate chamber 221 and the inside of the annular recess 29 are in communication through the gap between the operating rod 5 and the operating rod insertion hole 28. As a result, the refrigerant enters the annular recess 29 from the intermediate chamber 221, and the pressure difference between the annular recess 29 and the return flow path 23 presses the O-ring 61 toward the retaining plate 62.

[0034] At this time, the small-diameter inner surface 29b of the annular recess 29 and the O-ring 61 are in contact around the entire circumference along a first circular line passing through point P1 in Figure 3. Also, the operating rod 5 and the O-ring 61 are in contact around the entire circumference along a second circular line passing through point P2 in Figure 3. Furthermore, the lower surface of the retaining plate 62 and the O-ring 61 are in contact around the entire circumference along a circular line passing through point P3 in Figure 3. As a result, the refrigerant in the return passage 23 and the refrigerant in the intermediate chamber 221 do not mix, meaning that the space between the return passage 23 and the intermediate chamber 221 is sealed. Note that a portion of the groove 62c is formed radially outward from point P3 on the retaining plate 62.

[0035] Here, the annular space SP1, surrounded by the bottom wall 29a and small-diameter inner surface 29b of the annular recess 29, the outer surface of the operating rod 5, and the surface of the O-ring 61, is partitioned by the first and second lines, but is in communication with the intermediate chamber 221, and refrigerant is supplied from the intermediate chamber 221 side.

[0036] Furthermore, the annular space SP2, enclosed by the lower surface of the retaining plate 62, the outer surface of the operating rod 5, and the surface of the O-ring 61, is partitioned by the second and third lines, but is in communication with the return passage 23 through the gap between the outer surface of the operating rod 5 and the inner circumference 62b, and refrigerant is supplied from the return passage 23 side.

[0037] However, the annular space SP3, surrounded by the lower surface of the retaining plate 62, the tapered surface 29c, the small-diameter inner circumferential surface 29b, and the surface of the O-ring 61, is partitioned by the first and third lines, and therefore does not communicate with the return flow path 23 or the intermediate chamber 221. As a result, if there were no groove 62c, refrigerant would not be supplied to the space SP3.

[0038] According to this embodiment, since a groove 62c is formed in the retaining plate 62, the space SP3 communicates with the return flow path 23 through the groove 62c. As a result, refrigerant containing lubricant is supplied to the space SP3 through the groove 62c, lubrication of the O-ring 61 is possible, thereby suppressing twisting and deterioration of the O-ring 61, and allowing the O-ring 61 to perform its function as a component for a long period of time despite its simple configuration.

[0039] (Second embodiment) Figure 5 is a perspective view showing a retaining plate 62A according to the second embodiment. The retaining plate 62A can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0040] The retaining plate 62A, like the first embodiment, is formed into an annular flat plate by press-forming, for example, a metal plate, and has a circular outer circumference 62Aa and a circular inner circumference 62Ab that are coaxial, and three grooves 62Ac extending toward the center are formed from the outer circumference 62Aa. It is preferable that the grooves (passage-forming portions) 62Ac, which in part constitute a refrigerant passage, are formed at equal intervals along the circumferential direction. The number of grooves 62Ac is not limited to three, but may be two or four or more. The shape of the grooves 62Ac may also be different. The outer diameter of the outer circumference 62Aa is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference 62Ab is larger than the outer diameter of the operating rod 5. In the retaining plate 62A, the same configuration as in the first embodiment will not be explained again.

[0041] According to this embodiment, since there are more grooves 62Ac than in the first embodiment, the amount of refrigerant supplied from the return passage 23 through the grooves 62Ac increases, further improving lubrication.

[0042] (Third embodiment) Figure 6 is a perspective view of the retaining plate 62B according to the third embodiment, viewed from one side, and Figure 7 is a perspective view of the retaining plate 62B according to the third embodiment, viewed from the other side. Figures 8 and 9 are cross-sectional views similar to those in Figure 3, showing the sealing device 6B of the third embodiment.

[0043] The sealing device 6B includes an O-ring 61 and a retaining plate 62B as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation is omitted. The retaining plate 62B, as in the first embodiment, is formed in an annular shape by press-forming a metal plate, for example, and has a circular outer circumference 62Ba and a circular inner circumference 62Bb that are coaxial, and three grooves 62Bc are formed from the outer circumference 62Ba toward the center. It is preferable that the grooves (passage forming portions) 62Bc, which in part constitute a passage for the refrigerant, are formed at equal intervals along the circumferential direction. The outer diameter of the outer circumference 62Ba is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference 62Bb is larger than the outer diameter of the operating rod 5. In the retaining plate 62B, the same configuration as in the second embodiment is omitted a redundant explanation. Note that the configuration in which three grooves 62Bc are formed is just one example. In other examples, there may be only one groove 62Bc or there may be multiple grooves 62Bc. The formation of three grooves 62Bc is a further example of the provision of multiple grooves 62Bc. When multiple grooves 62Bc are formed, it is preferable that the multiple grooves 62Bc are arranged at equal intervals in the circumferential direction.

[0044] Furthermore, the retaining plate 62B has a flat plate portion 62Bd with an inner circumference portion 62Bb formed thereon, and a tapered plate portion (also called a tapered portion) 62Bf connected to the outer circumference of the flat plate portion 62Bd and inclined to widen in diameter as it moves away from the flat plate portion 62Bd. That is, the flat plate portion 62Bd has a shape that extends in a direction perpendicular to the axis, and the tapered plate portion 62Bf is connected to the flat plate portion 62Bd and has a shape that extends in a direction inclined with respect to the flat plate portion 62Bd, and has an outer circumference portion 62Ba. Three grooves 62Bc are formed in the tapered plate portion 62Bf. The tip of each of the three groove portions 62Bc is formed in the flat plate portion 62Bd. In this embodiment, a part of the grooves 62Bc is formed in the flat plate portion 62Bd, but in other examples, the grooves 62Bc may be formed only within the tapered plate portion 62Bf. The O-ring 61 abuts against the flat plate portion 62Bd. A circular bend line FL is formed at the boundary between the flat plate portion 62Bd and the tapered plate portion 62Bf. Figures 6 and 8 show the retaining plate 62B in a position where the flat plate portion 62Bd is higher than the tapered plate portion 62Bf (first position), while Figures 7 and 9 show the retaining plate 62B in a position where the flat plate portion 62Bd is lower than the tapered plate portion 62Ee (second position).

[0045] As shown in Figure 8, the retaining plate 62B can be attached to the annular recess 29 in a first position. Specifically, when the retaining plate 62B is inserted into the medium-diameter inner circumferential surface 29e and the outer periphery portion 62Ba is in contact with the intermediate surface 29d, pressing the flat plate portion 62Bd of the retaining plate 62B downward from above causes the retaining plate 62B to plastically deform, and the outer periphery portion 62Ba expands radially outward, so that the outer periphery portion 62Ba can be pressed against the medium-diameter inner circumferential surface 29e. As a result, unlike the first embodiment, it is not necessary to hammer and dent the recess surrounding surface 29f around the medium-diameter inner circumferential surface 29e, and the retaining plate 62B can be easily assembled.

[0046] In contrast, as shown in Figure 9, the retaining plate 62B can also be attached to the annular recess 29 in a second position. Specifically, after inserting the retaining plate 62B into the medium-diameter inner circumferential surface 29e, the same attachment method as in the first position shown in Figure 8 is used. That is, when the tapered plate portion 62Bf of the retaining plate 62B is pressed downward from above while the outer periphery portion 62Ba is in contact with the intermediate surface 29d, the retaining plate 62B undergoes plastic deformation, and the outer periphery portion 62Ba expands radially outward, thus allowing the outer periphery portion 62Ba to be pressed against the medium-diameter inner circumferential surface 29e. After assembly, when the flat plate portion 62Bd of the retaining plate 62B receives pressure from the O-ring 61 side, the outer periphery portion 62Ba undergoes elastic deformation so as to protrude radially outward, thereby autonomously preventing the retaining plate 62B from falling off.

[0047] Alternatively, when the retaining plate 62B is attached to the annular recess 29 in the second position, the retaining plate 62B may have an outer diameter of its outer circumference 62Ba that is larger than the inner diameter of the medium-diameter inner surface 29e of the annular recess 29 in its pre-attachment state. Even if the outer diameter of the outer circumference 62Ba is larger than the inner diameter of the medium-diameter inner surface 29e of the annular recess 29 in its pre-attachment state, when the retaining plate 62B is inserted into the medium-diameter inner surface 29e in the second position and pressed, the tapered plate portion 62Bf acts as a guide and deforms, allowing the retaining plate 62B to be pushed in until the outer circumference 62Ba contacts the medium-diameter inner surface 29e, as shown in Figure 9. As a result, the retaining plate 62B can be fixed in a state where the outer circumference 62Ba is pressed against the medium-diameter inner surface 29e, as shown in Figure 9.

[0048] (Fourth embodiment) Figure 10 is a cross-sectional view similar to Figure 3, showing the sealing device 6C of the fourth embodiment. Figure 11 is a perspective view showing the retaining plate 62C according to the fourth embodiment.

[0049] The sealing device 6C includes an O-ring 61 and a retaining plate 62C as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation is omitted. The retaining plate 62C, like in the first embodiment, is formed into an annular flat plate by press-forming, for example, a metal plate, and has a circular outer circumference 62Ca and a circular inner circumference 62Cb that are coaxial. A circular through hole (passage forming portion) 62Cc is formed between the outer circumference 62Ca and the inner circumference 62Cb. The through hole 62Cc constitutes a passage for the refrigerant. The outer diameter of the outer circumference 62Ca is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference 62Cb is larger than the outer diameter of the operating rod 5. In the retaining plate 62C, the same configuration as in the first embodiment is omitted a redundant explanation.

[0050] According to this embodiment, since a through hole 62Cc is formed in the retaining plate 62C, the space SP3 communicates with the return flow path 23 through the through hole 62Cc, as shown in Figure 10. As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61.

[0051] (Fifth embodiment) Figure 12 is a perspective view of the retaining plate 62D according to the fifth embodiment, viewed from one side, and Figure 13 is a perspective view of the retaining plate 62D according to the fifth embodiment, viewed from the other side. The retaining plate 62D can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0052] The retaining plate 62D, like in the first embodiment, is formed in an annular shape by press-forming a metal plate, for example, and has a circular outer circumference 62Da and a circular inner circumference 62Db that are coaxial, and has a through hole (passage forming portion) 62Dc between the outer circumference 62Da and the inner circumference 62Db that constitutes a passage for the refrigerant. The outer diameter of the outer circumference 62Da is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference 62Db is larger than the outer diameter of the operating rod 5. In the retaining plate 62D, the same configuration as in the first embodiment will not be explained again.

[0053] Furthermore, the retaining plate 62D has a flat plate portion 62Dd with an inner circumference portion 62Db, and a tapered plate portion (also called a tapered portion) 62De connected to the outer circumference of the flat plate portion 62Dd, which is inclined to widen in diameter as it moves away from the flat plate portion 62Dd. That is, the flat plate portion 62Dd has a shape that extends in a direction perpendicular to the axis, and the tapered plate portion 62De is connected to the flat plate portion 62Dd and has a shape that extends in a direction inclined with respect to the flat plate portion 62Dd, and has an outer circumference portion 62Da. A part of the through hole 62Dc is formed in the tapered plate portion 62De, and the other part is formed in the flat plate portion 62Dd. Note that the arrangement of the through hole 62Dc shown in Figure 12 is just one example. In other examples, the through hole 62Dc may be formed only in the tapered plate portion 62De, or the through hole 62Dc may be formed only in the flat plate portion 62Dd.

[0054] The O-ring 61 abuts against the flat plate portion 62Dd. A circular bend line FL is formed at the boundary between the flat plate portion 62Dd and the tapered plate portion 62De. The retaining plate 62D can be attached to the annular recess 29 in a position where the flat plate portion 62Dd is higher than the tapered plate portion 62De (first position), as shown in Figure 12, or in a position where the flat plate portion 62Dd is lower than the tapered plate portion 62Ae (second position), as shown in Figure 13. Attaching the retaining plate 62D in the first and second positions is the same as the attachment described using Figures 8 and 9 of the third embodiment. Attaching the retaining plate 62D in the first position has the same effect as the embodiment described in Figure 8, and attaching the retaining plate 62D in the second position has the same effect as the embodiment described in Figure 9.

[0055] (Sixth embodiment) Figure 14 is a perspective view showing a retaining plate 62E according to the sixth embodiment. The retaining plate 62E can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0056] The retaining plate 62E, similar to the first embodiment, is formed into an annular flat plate by, for example, press-forming a metal plate, and has a circular outer circumference 62Ea and a circular inner circumference 62Eb that are coaxial, and has a plurality of through holes 62Ec, for example three, that are equally spaced along the circumferential direction between the outer circumference 62Ea and the inner circumference 62Eb. Note that the arrangement of the plurality of through holes 62Ec does not have to be equally spaced. The number of through holes (passage forming parts) 62Ec that constitute the refrigerant passage is not limited to three, but may be two or four or more. The diameters of the through holes 62Ec may be different. The outer diameter of the outer circumference 62Ea is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the inner circumference 62Eb is larger than the outer diameter of the operating rod 5. In the retaining plate 62E, the same configuration as in the first embodiment will not be explained again.

[0057] According to this embodiment, since the number of through-holes 62Ec is greater than in the above embodiment, the amount of refrigerant supplied from the return flow path 23 through the through-holes 62Ec is increased, and lubrication can be further improved.

[0058] (Seventh Embodiment) Figure 15 is a cross-sectional view similar to Figure 3, showing the sealing device 6F of the seventh embodiment. Figure 16 is a perspective view showing the retaining plate 62F according to the seventh embodiment.

[0059] The sealing device 6F includes an O-ring 61 and a retaining plate 62F as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation will be omitted. The retaining plate 62F, as in the first embodiment, is formed into an annular flat plate by press-forming, for example, a metal plate, and has a circular outer periphery 62Fa and an opening (hole) 62Fb. When the retaining plate 62F is viewed from above, the opening 62Fb has a shape in which a coaxial partial circular hole (first portion through which the operating rod 5 is inserted) 62Fb1 and an elongated hole (second portion, passage forming portion) 62Fb2 extending radially outward from the partial circular hole 62Fb1 beyond the O-ring 61 are superimposed. The outer diameter of the outer circumference portion 62Fa is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the partially circular hole portion 62Fb1 is larger than the outer diameter of the operating rod 5. Regarding the retaining plate 62F, a configuration similar to that of the first embodiment will not be explained again.

[0060] According to this embodiment, since the retaining plate 62F has an elongated hole 62Fb2, the space SP3 communicates with the return passage 23 through the elongated hole 62Fb2, as shown in Figure 15. As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61. When the O-ring 61 contacts the retaining plate 62F, it intersects with the elongated hole 62Fb2, but the O-ring 61 seals by contacting the small-diameter inner circumferential surface 29b with the operating rod 5, so the movement of refrigerant between the intermediate chamber 221 and the return passage 23 is prevented.

[0061] (Eighth embodiment) Figure 17 is a perspective view showing a retaining plate 62G according to the eighth embodiment. The retaining plate 62G can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0062] The retaining plate 62G is formed into an annular flat plate by press-forming, for example, a metal plate, similar to the first embodiment, and has an outer periphery 62Ga and an opening (hole) 62Gb. When the retaining plate 62G is viewed from above, the opening 62Gb has a shape in which a coaxial partial circular hole (first portion through which the operating rod 5 is inserted) 62Gb1 is superimposed on the outer periphery 62Ga, and a plurality of, for example, three elongated holes (second portion, passage forming portion, part of which constitutes a passage for the refrigerant) 62Gb2 extending radially outward from the partial circular hole 62Gb1. It is preferable that the angles between adjacent elongated holes 62Gb2 are equal. That is, the plurality of elongated holes 62Gb2 may be arranged at equal intervals. In other examples, the arrangement of the plurality of elongated holes 62Gb2 does not have to be at equal intervals. The number of elongated holes 62Gb2 is not limited to three, but may be two or four or more. The shape of the elongated hole portion 62Gb2 may be varied. The outer diameter of the outer peripheral portion 62Ga is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the partially circular hole portion 62Gb1 is larger than the outer diameter of the operating rod 5. In the retaining plate 62G, the same configuration as in the first embodiment will not be explained again.

[0063] According to this embodiment, since there are more elongated holes 62Gb2 compared to the seventh embodiment, the amount of refrigerant supplied from the return flow path 23 through the elongated holes 62Gb2 increases, further improving lubrication.

[0064] In the embodiments described above, passages for the refrigerant are provided by forming through holes or grooves in the retaining plate. However, in the following embodiments 9 to 11, a passage for the refrigerant (passage-forming portion) is formed between the outer circumference and the medium-diameter inner surface 29e of the retaining plate.

[0065] (Ninth embodiment) Figure 18 is a cross-sectional view similar to Figure 3, showing a sealing device 6H according to the ninth embodiment. Figure 19 is a perspective view showing a retaining plate 62H according to the ninth embodiment.

[0066] The sealing device 6H includes an O-ring 61 and a retaining plate 62H as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation will be omitted. The retaining plate 62H, as in the first embodiment, is formed in a substantially square shape by press-forming, for example, a metal plate, and has an outer periphery 62Ha and a circular opening 62Hb. The outer periphery 62Ha has a configuration in which four straight sections 62Ha1 of equal length and four connecting sections 62Ha2 are alternately connected.

[0067] When the retaining plate 62H is viewed from above, it has a non-circular shape, and the connecting portion 62Ha2 constitutes a part of a circle coaxial with the opening 62Hb. The diameter of the circle formed by the connecting portion 62Ha2 is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the opening 62Hb is larger than the outer diameter of the operating rod 5. With the connecting portion 62Ha2 in contact with the medium-diameter inner surface 29e, the retaining plate 62H can be attached to the annular recess 29 by striking and denting the recess circumferential surface 29f around the medium-diameter inner surface 29e in the vicinity of the contact portion. In the retaining plate 62H, the same configuration as in the first embodiment will not be explained again.

[0068] According to this embodiment, since a straight section 62Ha1 is formed on the retaining plate 62H, only the connecting section 62Ha2 of the retaining plate 62H abuts against the medium-diameter inner circumferential surface 29e, and a refrigerant passage (passage forming section) is formed between the straight section 62Ha1 and the medium-diameter inner circumferential surface 29e. As a result, as shown in Figure 18, the space SP3 communicates with the return passage 23 through the gap between the straight section 62Ha1 and the medium-diameter inner circumferential surface 29e. This allows refrigerant containing lubricant to be supplied to the space SP3, thereby lubricating the O-ring 61 and suppressing twisting and deterioration of the O-ring 61.

[0069] (Tenth embodiment) Figure 20 is a perspective view showing a retaining plate 62I according to the tenth embodiment. The retaining plate 62I can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0070] The retaining plate 62I, similar to the first embodiment, is formed in a substantially equilateral triangular plate shape by, for example, press-forming a metal plate, and has an outer periphery 62Ia and a circular opening 62Ib. The outer periphery 62Ia has a configuration in which three straight sections 62Ia1 and three connecting sections 62Ia2 of equal length are alternately connected.

[0071] When the retaining plate 62I is viewed from above, it has a non-circular shape, and the connecting portion 62Ia2 constitutes a part of a circle coaxial with the opening 62Ib. The diameter of the circle formed by the connecting portion 62Ia2 is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29e of the annular recess 29, and the inner diameter of the opening 62Ib is larger than the outer diameter of the operating rod 5. With the connecting portion 62Ia2 in contact with the medium-diameter inner circumferential surface 29e, the retaining plate 62I can be attached to the annular recess 29 by striking and denting the recess circumferential surface 29f around the medium-diameter inner circumferential surface 29e in the vicinity of the contact portion. In the retaining plate 62I, the same configuration as in the first embodiment will not be explained again.

[0072] According to this embodiment, since a straight portion 62Ia1 is formed on the retaining plate 62I, only the connecting portion 62Ia2 of the retaining plate 62I abuts against the medium-diameter inner circumferential surface 29e, and a refrigerant passage (passage forming portion) is formed between the straight portion 62Ia1 and the medium-diameter inner circumferential surface 29e. As a result, the space SP3 (see Figure 18) communicates with the return passage 23 through the gap between the straight portion 62Ia1 and the medium-diameter inner circumferential surface 29e. This allows refrigerant containing lubricant to be supplied to the space SP3, thereby lubricating the O-ring 61 and suppressing twisting and deterioration of the O-ring 61.

[0073] (11th embodiment) Figure 21 is a perspective view showing a retaining plate 62J according to the eleventh embodiment. The retaining plate 62J can be used in place of the retaining plate 62 in the sealing device 6 of the first embodiment.

[0074] The retaining plate 62J, similar to the first embodiment, is formed in a substantially circular plate shape by, for example, press-forming a metal plate, and has an outer circumference 62Ja and a circular opening 62Jb. When the retaining plate 62J is viewed from above, the outer circumference 62Ja has a shape obtained by linearly cutting the outer circumference of a circle that is coaxial with the opening 62Jb, that is, it has an arc-shaped portion 62Ja1 and a straight portion 62Ja2. Therefore, the retaining plate 62H has a non-circular shape.

[0075] The diameter of the circle formed by the arc-shaped portion 62Ja1 is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29e of the annular recess 29, and the inner diameter of the opening 62Jb is larger than the outer diameter of the operating rod 5. With the arc-shaped portion 62Ja1 in contact with the medium-diameter inner circumferential surface 29e, the retaining plate 62J can be attached to the annular recess 29 by striking and denting the recess circumferential surface 29f around the medium-diameter inner circumferential surface 29e in the vicinity of the contact point. The configuration of the retaining plate 62J is the same as in the first embodiment, so a redundant explanation will be omitted.

[0076] According to this embodiment, since a straight portion 62Ja2 is formed on the retaining plate 62J, only the arc-shaped portion 62Ja1 of the retaining plate 62J abuts against the medium-diameter inner circumferential surface 29e, and a refrigerant passage (passage-forming portion) is formed between the straight portion 62Ja2 and the medium-diameter inner circumferential surface 29e. As a result, the space SP3 (see Figure 18) communicates with the return passage 23 through the gap between the straight portion 62Ja2 and the medium-diameter inner circumferential surface 29e. This allows refrigerant containing lubricant to be supplied to the space SP3, thereby lubricating the O-ring 61 and suppressing twisting and deterioration of the O-ring 61.

[0077] (12th embodiment) Figure 22 is a cross-sectional view similar to Figure 3 showing the sealing device 6K of the twelfth embodiment. Figure 23 is a perspective view of the retaining plate 62K according to the twelfth embodiment, viewed from one side, and Figure 24 is a perspective view of the retaining plate 62K according to the twelfth embodiment, viewed from the other side.

[0078] The sealing device 6K includes an O-ring 61 and a retaining plate 62K as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation will be omitted. The retaining plate 62K, as in the first embodiment, is formed in a disc shape by press-forming, for example, a metal plate, and has a circular outer circumference 62Ka, a circular opening 62Kb, and a plurality of semi-cylindrical portions 62Kc extending radially to connect the outer circumference 62Ka and the opening 62Kb. The semi-cylindrical portions 62Kc are formed to protrude in a semi-cylindrical shape from the rest of the surface of the retaining plate 62K. In other words, the raised portion has a semi-cylindrical portion 62Kc as a projection formed on the upper surface of the retaining plate 62K and projecting away from the upper surface, and a recess formed on the lower surface of the retaining plate 62K in the portion facing the semi-cylindrical portion 62Kc in the thickness direction of the retaining plate 62K, and recessed in accordance with the shape of the semi-cylindrical portion 62Kc. Preferably, the angle between adjacent semi-cylindrical portions 62Kc is equal. In other words, multiple semi-cylindrical portions 62Kc may be arranged at equal intervals. In other examples, the arrangement of multiple semi-cylindrical portions 62Kc does not have to be at equal intervals. The number of semi-cylindrical portions 62Kc is not limited to four, but may be one to three, or five or more. The semi-cylindrical portion 62Kc is, for example, semi-cylindrical, but may have other shapes, and in other examples, it may be a polygonal cylindrical shape such as a triangle or square, or a semi-elliptical cylindrical shape.

[0079] The outer diameter of the outer circumference portion 62Ka is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the opening 62Kb is larger than the outer diameter of the operating rod 5. With the outer circumference portion 62Ka in contact with the medium-diameter inner surface 29e, the retaining plate 62K can be attached to the annular recess 29 by striking and denting the recess surrounding surface 29f around the medium-diameter inner surface 29e near the contact point. In this embodiment, the height of the semi-cylindrical portion 62Kc is lower than the height of the medium-diameter inner surface 29e. For this reason, the opening at the radially outer end of the semi-cylindrical portion 62Kc is closed by the medium-diameter inner surface 29e.

[0080] When the O-ring 61 contacts the retaining plate 62K, it intersects with the semi-cylindrical portion 62Kc, but a gap is created between the O-ring 61 and the inner circumference of the semi-cylindrical portion 62Kc. That is, when the retaining plate 62K is fixed to the medium-diameter inner surface 29e in a position where the semi-cylindrical portion 62Kc protrudes toward the return flow path 23, the refrigerant passage (passage forming portion) includes the gap between the recess and the O-ring 61, and the gap between the operating rod 5 and the opening 62Kb. In the retaining plate 62K, the same configuration as in the first embodiment will not be explained again.

[0081] According to this embodiment, since a semi-cylindrical portion 62Kc is formed on the retaining plate 62K, as shown in Figure 22, when the retaining plate 62K is attached to the annular recess 29, the space SP3 communicates with the return flow path 23 through the gap between the opening 62Kb and the operating rod 5, and the gap between the O-ring 61 and the inner circumference of the semi-cylindrical portion 62Kc (which constitute a refrigerant passage (passage forming portion)). As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61.

[0082] In addition, the sealing device can also be assembled with the retaining plate 62K inverted so that the semi-cylindrical portion 62Kc protrudes downward from the lower surface of the retaining plate 62K, as shown in the assembly configuration of Figure 22. In this case, the semi-cylindrical portion 62Kc will intersect and contact the O-ring 61. That is, when the retaining plate 62K is fixed to the medium-diameter inner circumferential surface 29e with the semi-cylindrical portion 62Kc facing the O-ring 61, the refrigerant passage (passage forming portion) includes the gap between the lower surface of the retaining plate 62K and the O-ring 61, and the gap between the operating rod 5 and the opening 62Kb. Since this gap communicates with the return passage 23, refrigerant can be supplied to the space SP3 through this gap.

[0083] (Modified version of the 12th embodiment) In the twelfth embodiment, as shown in Figure 22, an example was described in which the height of the semi-cylindrical portion 62Kc is lower than the height of the medium-diameter inner circumferential surface 29e, and therefore the opening at the end opposite to the opening 62Kb of the semi-cylindrical portion 62Kc (the radially outer end opening according to the twelfth embodiment) is closed by the medium-diameter inner circumferential surface 29e. In other examples, the height of the semi-cylindrical portion 62Kc is set to a dimension higher than the height of the medium-diameter inner circumferential surface 29e, and therefore a portion of the opening at the radially outer end of the semi-cylindrical portion 62Kc may open towards the return flow path 23 from the retaining plate 62K.

[0084] This example will be explained using Figures 25 and 26. Figure 25 is a cross-sectional view similar to Figure 3, showing a modified sealing device 6K according to the twelfth embodiment. Figure 26 is a perspective view showing the sealing device 6K according to this modified embodiment and its surroundings, partially cut away.

[0085] As shown in Figures 25 and 26, the height of the semi-cylindrical portion 62Kc in this modified example is higher than the height of the intermediate inner circumferential surface 29e. Therefore, when the retaining plate 62K is fixed to the valve body 2, a portion of the opening at the radially outer end of the semi-cylindrical portion 62Kc opens towards the return passage 23.

[0086] According to this modified example, when the retaining plate 62K is attached to the annular recess 29, the space SP3 communicates with the return flow path 23 through the gap between the opening 62Kb and the operating rod 5, and the gap between the O-ring 61 and the inner circumference of the semi-cylindrical portion 62Kc (which constitute a refrigerant passage (passage forming portion)). Furthermore, the space SP3 communicates with the return flow path 23 through the opening at the radially outer end of the semi-cylindrical portion 62Kc. It is preferable that one of the semi-cylindrical portions 62Kc faces the upstream side of the return flow path 23, as this makes it easier for the refrigerant flowing through the return flow path 23 to enter the semi-cylindrical portion 62Kc.

[0087] (13th embodiment) Figure 27 is a cross-sectional view similar to Figure 3 showing the sealing device 6L of the 13th embodiment. Figure 28 is a perspective view of the retaining plate 62L according to the 13th embodiment, viewed from one side, and Figure 29 is a perspective view of the retaining plate 62L according to the 13th embodiment, viewed from the other side.

[0088] The sealing device 6L includes an O-ring 61 and a retaining plate 62L as a retaining member for holding the O-ring 61. The O-ring 61 and the annular recess 29 have the same configuration as in the first embodiment, so a redundant explanation will be omitted. The retaining plate 62L, as in the first embodiment, is formed in a disc shape by press-forming, for example, a metal plate, and has a circular outer circumference 62La, a circular opening 62Lb, and four hemispherical portions 62Lc between the outer circumference 62La and the opening 62Lb. The hemispherical portions 62Lc are formed to protrude hemispherically from the other surfaces of the retaining plate 62L, are positioned opposite the O-ring 61, and constitute the protruding portion. In other words, the raised portion has a hemispherical portion 62Lc formed on the upper surface of the retaining plate 62L and projecting away from the upper surface, and a recess formed on the lower surface of the retaining plate 62L in the portion opposite to the hemispherical portion 62Lc in the thickness direction of the retaining plate 62L, and recessed in accordance with the shape of the hemispherical portion 62Lc. It is preferable that adjacent hemispherical portions 62Lc are formed at equal intervals in the circumferential direction. The number of hemispherical portions 62Lc is not limited to four, but may be one to three, or five or more. As described above, the hemispherical portion 62Lc is an example of a projection formed on the upper surface of the retaining plate 62L and projecting away from the upper surface. The hemispherical shape is just one example, and other examples of the external shape of the projection may be a polygonal columnar shape such as a triangular prism or a square prism. Alternatively, as another example, the external shape may be a polygonal pyramid such as a triangular pyramid or a square pyramid.

[0089] The outer diameter of the outer circumference portion 62La is approximately equal to the inner diameter of the medium-diameter inner surface 29e of the annular recess 29, and the inner diameter of the opening 62Lb is larger than the outer diameter of the operating rod 5. With the outer circumference portion 62La in contact with the medium-diameter inner surface 29e, the retaining plate 62L can be attached to the annular recess 29 by striking and denting the recess surrounding surface 29f around the medium-diameter inner surface 29e near the contact point. That is, when the retaining plate 62L is fixed to the medium-diameter inner surface 29e in a position where the hemispherical portion 62Lc protrudes toward the return flow path 23, the refrigerant passage (passage forming portion) includes the gap between the recess and the O-ring 61, and the gap between the operating rod 5 and the opening 62Lb. Through this gap, the inner space of the hemispherical portion 62Lc can communicate with the gap and space SP3 between the opening 62Lb and the operating rod 5. In the case of the retaining plate 62L, the same configuration as in the first embodiment will not be explained again.

[0090] According to this embodiment, since a hemispherical portion 62Lc is formed on the retaining plate 62L, as shown in Figure 27, when the retaining plate 62L is attached to the annular recess 29, the space SP3 communicates with the return flow path 23 through the gap between the opening 62Lb and the operating rod 5, and the gap between the O-ring 61 and the inner space of the hemispherical portion 62Lc (which constitute a refrigerant passage (passage forming portion)). As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61.

[0091] In addition, the sealing device can also be assembled with the retaining plate 62L inverted so that the hemispherical portion 62Lc protrudes downward from the lower surface of the retaining plate 62L, as shown in the assembly configuration of Figure 27. In this case, the hemispherical portion 62Lc will be in contact with the O-ring 61. That is, when the retaining plate 62L is fixed to the medium-diameter inner circumferential surface 29e with the hemispherical portion 62Lc facing the O-ring 61, the refrigerant passage (passage forming portion) includes the gap between the lower surface of the retaining plate 62L and the O-ring 61, and the gap between the operating rod 5 and the opening 62Lb. Since this gap communicates with the return passage 23, refrigerant can be supplied to the space SP3 through this gap.

[0092] (14th embodiment) Figure 30 is a cross-sectional view similar to Figure 3, showing a sealing device 6M according to the 14th embodiment. Figure 31 is a perspective view showing a retaining member 62M according to the 14th embodiment.

[0093] The sealing device 6M includes an O-ring 61 and a retaining member 62M that holds the O-ring 61. The O-ring 61 has the same configuration as in the first embodiment, so a redundant explanation is omitted. The annular recess 29 has the same configuration as in the first embodiment, except that the medium-diameter inner circumferential surface 29Me is elongated in the vertical direction, so a redundant explanation is omitted.

[0094] The retaining member 62M is formed into a cylindrical shape from a metal material, for example, by forging or machining, and has a shape in which a large-diameter cylindrical portion 62Ma and a small-diameter cylindrical portion 62Mb, which has a smaller diameter than the large-diameter cylindrical portion 62Ma, are coaxially connected. The retaining member 62M also has a circular opening 62Md that penetrates vertically coaxially with the large-diameter cylindrical portion 62Ma, and a through hole 62Mc. The through hole 62Mc extends along the axial direction of the large-diameter cylindrical portion 62Ma and is, for example, a hole parallel to the large-diameter portion 62Ma. The through hole 62Mc that constitutes the refrigerant passage (passage forming portion) is formed in a position that interferes with the small-diameter cylindrical portion 62Mb, but it may also be formed to penetrate only the large-diameter cylindrical portion 62Ma without interfering with the small-diameter cylindrical portion 62Mb.

[0095] The outer diameter of the large-diameter cylindrical portion 62Ma is approximately equal to the inner diameter of the medium-diameter inner surface 29Me of the annular recess 29, and the inner diameter of the circular opening 62Md is larger than the outer diameter of the operating rod 5. With the large-diameter cylindrical portion 62Ma fitted into the medium-diameter inner surface 29Me, the retaining member 62M can be attached to the annular recess 29 by striking and denting the area around the medium-diameter inner surface 29Me near the contact point. At this time, a tapered surface 29c is formed so that the intersection of the large-diameter cylindrical portion 62Ma and the small-diameter cylindrical portion 62Mb does not interfere with the inner wall of the annular recess 29. However, the large-diameter cylindrical portion 62Ma may be press-fitted into the medium-diameter inner surface 29Me.

[0096] The O-ring 61 abuts against the lower end of the small-diameter cylindrical portion 62Mb that has entered the small-diameter inner circumferential surface 29b. In this case, it is preferable that the through hole 62Mc is formed radially outward from the contact point P3 between the O-ring 61 and the small-diameter cylindrical portion 62Mb.

[0097] According to this embodiment, since a through hole 62Mc is formed in the retaining member 62M, as shown in Figure 30, when the retaining member 62M is attached to the annular recess 29, the space SP3 communicates with the return flow path 23 through the through hole 62Mc. As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61.

[0098] (15th embodiment) Figure 32 is a perspective view showing a retaining member 62N according to the 15th embodiment. The retaining member 62N can be used in place of the retaining member 62M in the sealing device 6M of the 14th embodiment.

[0099] The retaining member 62N, similar to the 14th embodiment, is formed in a cylindrical shape from a metal material, for example, by forging or cutting, and has a shape in which a large-diameter cylindrical portion 62Na and a small-diameter cylindrical portion 62Nb, which has a smaller diameter than the large-diameter cylindrical portion 62Na, are coaxially connected. The retaining member 62N also has a circular opening 62Nd that penetrates vertically coaxially with the large-diameter cylindrical portion 62Na, and a plurality of through holes 62Nc, for example, three. It is preferable that the through holes 62Nc are formed at equal intervals along the circumferential direction. The plurality of through holes 62Nc extend along the axis of the circular opening 62Nd and are, for example, holes parallel to the circular opening 62Nd. The number of through holes 62Nc that constitute the refrigerant passage (passage forming portion) is not limited to three, but may be two or four or more. The diameters of the through holes 62Nc may be different. The outer diameter of the large-diameter cylindrical portion 62Na is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29Me of the annular recess 29, and the inner diameter of the circular opening 62Nd is larger than the outer diameter of the operating rod 5. Regarding the retaining member 62N, a configuration similar to that of the 14th embodiment will not be explained again.

[0100] According to this embodiment, since the number of through-holes 62Nc is greater than in the 14th embodiment, the amount of refrigerant supplied from the return flow path 23 through the through-holes 62Nc is increased, and lubrication can be further improved.

[0101] (16th embodiment) Figure 33 is a cross-sectional view similar to Figure 3, showing the sealing device 6O of the 16th embodiment. Figure 34 is a perspective view showing the retaining member 62O according to the 16th embodiment.

[0102] The sealing device 6O includes an O-ring 61 and a retaining member 62O that holds the O-ring 61. The O-ring 61 has the same configuration as in the first embodiment, so a redundant explanation is omitted. The annular recess 29 has the same configuration as in the first embodiment, except that the medium-diameter inner circumferential surface 29Oe is elongated in the vertical direction, so a redundant explanation is omitted.

[0103] The retaining member 62O, similar to the 14th embodiment, is formed in a cylindrical shape from a metal material, for example, by forging or cutting, and has a shape in which a large-diameter cylindrical portion 62Oa and a small-diameter cylindrical portion 62Ob, which has a smaller diameter than the large-diameter cylindrical portion 62Oa, are coaxially connected. The retaining member 62O also has a circular opening 62Od that penetrates vertically coaxially with the large-diameter cylindrical portion 62Oa, and a groove 62Oc that extends radially inward from the outer circumference of the large-diameter cylindrical portion 62Oa. The groove 62Oc, which in part constitutes a passage for refrigerant (passage forming portion), is formed to reach near the boundary between the large-diameter cylindrical portion 62Oa and the small-diameter cylindrical portion 62Ob.

[0104] The outer diameter of the large-diameter cylindrical portion 62Oa is approximately equal to the inner diameter of the medium-diameter inner surface 29Oe of the annular recess 29, and the inner diameter of the circular opening 62Od is larger than the outer diameter of the operating rod 5. With the large-diameter cylindrical portion 62Oa fitted into the medium-diameter inner surface 29Oe, the retaining member 62O can be attached to the annular recess 29 by striking and denting the area around the medium-diameter inner surface 29Oe near the contact point. At this time, a tapered surface 29c is formed so that the intersection of the large-diameter cylindrical portion 62Oa and the small-diameter cylindrical portion 62Ob does not interfere with the inner wall of the annular recess 29. However, the large-diameter cylindrical portion 62Oa may be press-fitted into the medium-diameter inner surface 29Oe.

[0105] The O-ring 61 abuts against the lower end of the small-diameter cylindrical portion 62Ob that enters the small-diameter inner circumferential surface 29b. At this time, it is preferable that the groove 62Oc is formed radially outward from the contact point P3 between the O-ring 61 and the small-diameter cylindrical portion 62Ob.

[0106] According to this embodiment, since a groove 62Oc is formed in the retaining member 62O, as shown in Figure 33, when the retaining member 62O is attached to the annular recess 29, the space SP3 communicates with the return flow path 23 via the groove 62Oc. As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61.

[0107] (Embodiment 17) Figure 35 is a perspective view showing a retaining member 62P according to the 17th embodiment. The retaining member 62P can be used in place of the retaining member 62M in the sealing device 6M of the 14th embodiment.

[0108] The retaining member 62P, similar to the 14th embodiment, is formed in a cylindrical shape from a metal material, for example, by forging or machining, and has a shape in which a large-diameter cylindrical portion 62Pa and a small-diameter cylindrical portion 62Pb, which has a smaller diameter than the large-diameter cylindrical portion 62Pa, are coaxially connected. The retaining member 62P also has a circular opening 62Pd that penetrates vertically coaxially with the large-diameter cylindrical portion 62Pa, and three grooves 62Pc. Preferably, the grooves 62Pc are formed at equal intervals along the circumferential direction. The number of grooves 62Pc, some of which constitute a refrigerant passage (passage forming portion), is not limited to three, but may be two or four or more. The shape of the grooves 62Pc may be different. The outer diameter of the large-diameter cylindrical portion 62Pa is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29Me of the annular recess 29, and the inner diameter of the circular opening 62Pd is larger than the outer diameter of the operating rod 5. In the retaining member 62P, the same configuration as in the 14th embodiment will not be explained again.

[0109] According to this embodiment, since the number of grooves 62Pc is greater than in the 16th embodiment, the amount of refrigerant supplied from the return flow path 23 through the grooves 62Pc is increased, and lubrication can be further improved.

[0110] (Embodiment 18) Figure 36 is a cross-sectional view similar to Figure 3, showing a sealing device 6Q according to the 18th embodiment. Figure 37 is a perspective view showing a retaining member 62Q according to the 18th embodiment.

[0111] The sealing device 6Q includes an O-ring 61 and a retaining member 62Q that holds the O-ring 61. The O-ring 61 has the same configuration as in the first embodiment, so a redundant explanation is omitted. The annular recess 29 has the same configuration as in the first embodiment, except that the medium-diameter inner circumferential surface 29Qe is elongated in the vertical direction, so a redundant explanation is omitted.

[0112] The retaining member 62Q, similar to the 14th embodiment, is formed into a cylindrical shape from a metal material, for example, by forging or cutting, and has a shape in which a large-diameter cylindrical portion 62Qa and a small-diameter cylindrical portion 62Qb, which has a smaller diameter than the large-diameter cylindrical portion 62Qa, are coaxially connected. The retaining member 62Q also has an opening (hole) 62Qc that penetrates vertically coaxially with the large-diameter cylindrical portion 62Qa.

[0113] When the retaining member 62Q is viewed from above, the opening 62Qc has a shape in which a coaxial partial circular hole (first portion through which the operating rod 5 is inserted) 62Qc1 and an elongated hole (second portion, passage-forming portion, part of which constitutes a passage for the refrigerant) 62Qc2 extending radially outward from the partial circular hole 62Qc1 are superimposed. The outer diameter of the large-diameter cylindrical portion 62Qa is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29Qe of the annular recess 29, and the inner diameter of the circle formed by the partial circular hole 62Qc1 is larger than the outer diameter of the operating rod 5. In the retaining member 62Q, the same configuration as in the 14th embodiment will not be explained again.

[0114] With the large-diameter cylindrical portion 62Qa fitted into the medium-diameter inner circumferential surface 29Qe, the retaining member 62Q can be attached to the annular recess 29 by striking and indenting the area around the medium-diameter inner circumferential surface 29Qe near the contact point. At this time, a tapered surface 29c is formed so that the intersection of the large-diameter cylindrical portion 62Qa and the small-diameter cylindrical portion 62Qb does not interfere with the inner wall of the annular recess 29. However, the large-diameter cylindrical portion 62Qa may also be press-fitted into the medium-diameter inner circumferential surface 29Qe. The O-ring 61 abuts against the lower end of the small-diameter cylindrical portion 62Qb that has entered the small-diameter inner circumferential surface 29b.

[0115] According to this embodiment, since the retaining member 62Q has an elongated hole 62Qc2, the space SP3 communicates with the return passage 23 through the elongated hole 62Qc2, as shown in Figure 36. As a result, refrigerant containing lubricant is supplied to the space SP3, which lubricates the O-ring 61 and suppresses twisting and deterioration of the O-ring 61. When the O-ring 61 comes into contact with the retaining member 62Q, it intersects with the elongated hole 62Qc2, but the O-ring 61 seals by contacting the small-diameter inner circumferential surface 29b with the operating rod 5, so the movement of refrigerant between the intermediate chamber 221 and the return passage 23 is prevented.

[0116] (19th embodiment) Figure 38 is a perspective view showing a retaining member 62R according to the 19th embodiment. The retaining member 62R can be used in place of the retaining member 62M in the sealing device 6M of the 14th embodiment.

[0117] The retaining member 62R, similar to the 14th embodiment, is formed into a cylindrical shape from a metal material, for example, by forging or machining, and has a shape in which a large-diameter cylindrical portion 62Ra and a small-diameter cylindrical portion 62Rb, which has a smaller diameter than the large-diameter cylindrical portion 62Ra, are coaxially connected. The retaining member 62R also has an opening (hole) 62Rc that penetrates in the vertical direction.

[0118] When the retaining member 62R is viewed from above, the opening 62Rc has a shape formed by superimposing a coaxial partial circular hole (first portion through which the operating rod 5 is inserted) 62Rc1 in the large-diameter cylindrical portion 62Ra and three elongated holes (second portion, passage-forming portion, part of which constitutes a refrigerant passage) 62Rc2 extending radially outward from the partial circular hole 62Rc1. Preferably, the angles between adjacent elongated holes 62Rc2 are equal. The number of elongated holes 62Rc2 is not limited to three, but may be two or four or more. The shapes of the elongated holes 62Rc2 may also be different. The outer diameter of the large-diameter cylindrical portion 62Ra is approximately equal to the inner diameter of the medium-diameter inner circumferential surface 29Me of the annular recess 29, and the inner diameter of the circle formed by the partial circular hole 62Rc1 is larger than the outer diameter of the operating rod 5. In the retaining member 62R, the same configuration as in the first embodiment will not be explained again.

[0119] According to this embodiment, since there are more elongated holes 62Rc2 compared to the 18th embodiment, the amount of refrigerant supplied from the return flow path 23 through the elongated holes 62Rc2 increases, further improving lubrication.

[0120] The present invention is not limited to the embodiments described above. Within the scope of the present invention, any component of the embodiments described above can be modified. Furthermore, any component can be added to or omitted in the embodiments described above.

[0121] This specification includes disclosures of the following inventions. (First aspect) A valve body comprising: an exhaust passage through which refrigerant that has passed through an orifice passes; a return passage through which refrigerant discharged to the outside via the exhaust passage enters; and a communication chamber connecting the exhaust passage and the return passage. Valve body and, An operating rod is provided, which is partially located in the return passage, the communication chamber, and the discharge passage, and which contacts the valve body. It has a sealing device arranged in the communication chamber that seals the space between the discharge side passage and the return passage, The sealing device comprises an annular seal that abuts against the inner wall of the communication chamber along the operating rod and the operating rod, and a retaining member that is positioned between the seal and the return passage side and fixed to the valve body, has a hole in which a part of the operating rod is positioned, and abuts against the seal to prevent the seal from moving toward the return passage side and holds the seal relative to the valve body. A space is formed between the seal, the inner wall of the communication chamber, and the retaining member. The retaining member of the sealing device has a passage forming portion that constitutes at least a part of a passage connecting the return flow path side from the retaining member to the space, allowing the refrigerant to pass through. An expansion valve characterized by the following features.

[0122] (Second aspect) The passage forming portion is a through hole formed between the outer periphery of the holding member and the hole. An expansion valve according to a first embodiment, characterized by the following:

[0123] (Third aspect) The passage forming portion is a part of the hole, An expansion valve according to a first embodiment, characterized by the following:

[0124] (Fourth aspect) The hole comprises a first portion in which the operating rod is positioned, and a second portion extending from the first portion toward the outer circumference of the holding member, with a portion of the second portion constituting the passage. A third embodiment of an expansion valve characterized by the following:

[0125] (Fifth aspect) The retaining member has a shape such that only a portion of its outer circumference abuts against the inner wall of the communication chamber. The passage forming portion is other than the part of the outer periphery. An expansion valve according to a first embodiment, characterized by the following:

[0126] (Sixth aspect) The cross-section of the inner wall of the communication chamber is circular, and the planar shape of the retaining member is non-circular. A fifth embodiment of an expansion valve characterized by the following:

[0127] (Seventh aspect) The passage forming portion is a groove that extends from the outer periphery of the holding member toward the hole and penetrates the holding member in the axial direction of the hole. An expansion valve according to a fifth or sixth embodiment, characterized by the following:

[0128] (Eighth aspect) The holding member is plate-shaped and has a flat portion and a tapered portion. The flat plate portion has the hole and has a shape that extends in a direction perpendicular to the axis of the hole. The tapered portion is connected to the flat plate portion and has a shape that extends in a direction inclined with respect to the flat plate portion, and has the outer circumference. An expansion valve according to a second or seventh embodiment, characterized by the above.

[0129] (Ninth aspect) The holding member is plate-shaped having one or more raised portions, The raised portion has a projection formed on one surface of the retaining member and projecting away from that surface, and a recess formed on the other surface of the retaining member in a portion facing the projection in the thickness direction of the retaining member, and recessed in a manner corresponding to the shape of the projection. When the retaining member is fixed to the communication chamber in a position in which the protruding portion protrudes toward the return flow path side, the passage includes the gap between the recess and the seal, and the hole, and the passage forming portion is the recess. When the retaining member is fixed in the communication chamber with the protruding portion facing the seal, the passage includes the gap between the one surface and the seal, and the passage forming portion is the portion of the one surface having the gap with respect to the seal. An expansion valve according to a first embodiment, characterized by the following: [Explanation of Symbols]

[0130] 1: Expansion valve 2: Valve body 3: Valve body 4: Biasing device 5: Actuator rod 6~6Q: Sealing device 61 O-rings 62~62L Retaining plate 62M~62R Retaining member 8: Power Element 20: Alveolar seat 21: First channel 22: Second channel 221: Intermediate Room 23: Return channel 27: Orifice hole 28: Actuator rod insertion hole 29: Annular recess 41: Coil spring 42: Valve support 43: Spring support member 100: Refrigerant circulation system 101: Compressor 102: Capacitor 103: Evaporator VC: Valve chamber

Claims

1. A valve body comprising: an exhaust passage through which the refrigerant that has passed through the orifice passes; a return passage through which the refrigerant discharged to the outside via the exhaust passage enters; and a communication chamber connecting the exhaust passage and the return passage. Valve body and, An operating rod is provided, which is partially located in the return passage, the communication chamber, and the discharge passage, and which contacts the valve body. It has a sealing device arranged in the communication chamber that seals the space between the discharge side passage and the return passage, The sealing device comprises an annular seal that abuts against the inner wall of the communication chamber along the operating rod and the operating rod, and a retaining member that is positioned between the seal and the return passage side and fixed to the valve body, has a hole in which a part of the operating rod is positioned, and abuts against the seal to prevent the seal from moving toward the return passage side and holds the seal relative to the valve body. A space is formed between the seal, the inner wall of the communication chamber, and the retaining member. The retaining member of the sealing device has a passage forming portion that constitutes at least a part of a passage connecting the return flow path side from the retaining member to the space, allowing the refrigerant to pass through. An expansion valve characterized by the following features.

2. The passage forming portion is a through hole formed between the outer periphery of the holding member and the hole. The expansion valve according to feature 1.

3. The passage forming portion is a part of the hole, The expansion valve according to feature 1.

4. The hole comprises a first portion in which the operating rod is positioned, and a second portion extending from the first portion toward the outer circumference of the holding member, with a portion of the second portion constituting the passage. The expansion valve according to claim 3.

5. The retaining member has a shape such that only a portion of its outer circumference abuts against the inner wall of the communication chamber. The passage forming portion is other than the part of the outer periphery. The expansion valve according to feature 1.

6. The cross-section of the inner wall of the communication chamber is circular, and the planar shape of the retaining member is non-circular. The expansion valve according to claim 5, characterized in that it is a feature of the present invention.

7. The passage forming portion is a groove that extends from the outer periphery of the holding member toward the hole and penetrates the holding member in the axial direction of the hole. The expansion valve according to claim 5, characterized in that it is a feature of the present invention.

8. The holding member is plate-shaped and has a flat portion and a tapered portion. The flat plate portion has the hole and has a shape that extends in a direction perpendicular to the axis of the hole. The tapered portion is connected to the flat plate portion and has a shape that extends in a direction inclined with respect to the flat plate portion, and has the outer circumference. The expansion valve according to feature 2 or 7.

9. The holding member is plate-shaped having one or more raised portions, The raised portion has a projection formed on one surface of the retaining member and projecting away from that surface, and a recess formed on the other surface of the retaining member in a portion facing the projection in the thickness direction of the retaining member, and recessed in a manner corresponding to the shape of the projection. When the retaining member is fixed to the communication chamber in a position in which the protruding portion protrudes toward the return flow path side, the passage includes the gap between the recess and the seal, and the hole, and the passage forming portion is the recess. When the retaining member is fixed in the communication chamber with the protruding portion facing the seal, the passage includes the gap between the one surface and the seal, and the passage forming portion is the portion of the one surface having the gap with respect to the seal. The expansion valve according to feature 1.

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