Seal ring

Abstract

The seal ring has an outer peripheral surface, an inner peripheral surface, a first side surface, and a second side surface. The seal ring includes an outer ring having an outer ring outer peripheral surface that constitutes the outer peripheral surface and a first outer ring side surface that constitutes the first side surface, and an inner ring having an inner ring inner peripheral surface that constitutes the inner peripheral surface and a first inner ring side surface that constitutes the second side surface. One of the outer ring and the inner ring is formed from a first resin having a flexural modulus of elasticity of 700 MPa or more, and the other is formed from a second resin having a flexural modulus of elasticity of less than 700 MPa. Of the outer ring and the inner ring, the one formed from the first resin has a joint.

Description

[Technical Field]

[0001] The present invention relates to a seal ring. [Background technology]

[0002] In recent years, there has been an increasing trend to replace metal components with resin components in order to reduce weight in applications such as in-vehicle equipment. Patent Document 1 discloses a resin seal ring. The seal ring described in Patent Document 1 is made of polyether ether ketone, a hard resin, so as to obtain high durability even in applications where high-pressure fluids are sealed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-327903 Summary of the Invention [Problem to be solved by the invention]

[0004] However, seal rings made of hard resins are prone to fluid leakage when used to seal high-pressure fluids. In other words, there is a trade-off between durability and leak prevention performance. Furthermore, hard resins are generally expensive, so the manufacturing costs of seal rings made of hard resins tend to be high.

[0005] In view of the above circumstances, an object of the present invention is to provide a seal ring that can achieve both durability and leak prevention performance. [Means for solving the problem]

[0006] A seal ring according to one embodiment of the present invention has an outer circumferential surface, an inner circumferential surface, a first side surface, and a second side surface. The seal ring comprises an outer ring having an outer ring outer surface that constitutes the outer peripheral surface and a first outer ring side surface that constitutes the first side surface, and an inner ring having an inner ring inner surface that constitutes the inner peripheral surface and a first inner ring side surface that constitutes the second side surface. One of the outer ring and the inner ring is formed from a first resin having a flexural modulus of 700 MPa or more, and the other is formed from a second resin having a flexural modulus of less than 700 MPa. The one of the outer ring and the inner ring made of the first resin has a joint.

[0007] The outer ring may be formed from the first resin, and the seal ring may seal the fluid on the inner periphery side.

[0008] In this case, the outer ring may further have an outer ring inner surface facing away from the outer ring outer surface and a second outer ring side surface facing away from the first outer ring side surface, and the inner ring may further have a first opposing surface facing the outer ring inner surface and a second opposing surface facing the outer ring side surface. Alternatively, the outer ring may further have an inner tapered surface inclined relative to the outer ring outer peripheral surface, and the inner ring may further have an outer tapered surface inclined relative to the inner ring inner peripheral surface and facing the inner tapered surface.

[0009] In these cases, the inner ring does not have to protrude from the outer peripheral surface of the outer ring and the first outer ring side surface. Conversely, the inner ring may protrude from the outer peripheral surface of the outer ring and the first outer ring side surface.

[0010] The joint portion may include a first engagement portion having an outer inclined surface connecting the outer ring outer peripheral surface and the first outer ring side surface, and a second engagement portion having an inner inclined surface opposite the outer inclined surface.

[0011] The inner ring may be formed from the first resin, and the seal ring may seal the fluid on the outer periphery side.

[0012] In this case, the inner ring may further have an inner ring outer surface facing away from the inner ring inner surface and a second inner ring side surface facing away from the first inner ring side surface, and the outer ring may further have a first opposing surface facing the inner ring outer surface and a second opposing surface facing the second inner ring side surface. Alternatively, the inner ring may further have an outer tapered surface inclined relative to the inner ring inner peripheral surface, and the outer ring may further have an inner tapered surface inclined relative to the outer ring outer peripheral surface and facing the outer tapered surface.

[0013] In these cases, the outer ring does not have to protrude from the inner peripheral surface of the inner ring and the first inner ring side surface. Conversely, the outer ring may protrude from the inner peripheral surface of the inner ring and the first inner ring side surface.

[0014] The joint portion may include a first engagement portion having an inner inclined surface connecting the inner ring inner peripheral surface and the first inner ring side surface, and a second engagement portion having an outer inclined surface facing the inner inclined surface. [Effects of the Invention]

[0015] The present invention can provide a seal ring that can achieve both durability and leak prevention performance. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a plan view of a seal ring according to a first embodiment of the present invention. [Figure 2] 2 is a cross-sectional view of the seal ring shown in FIG. 1 taken along line AA'. [Figure 3] 2 is a cross-sectional view showing a state in which the seal ring shown in FIG. 1 is assembled to a movable scroll and a housing. [Figure 4] 2 is a partial perspective view showing a joint portion of an outer ring of the seal ring shown in FIG. 1. FIG. [Figure 5] 10A and 10B are diagrams showing other structural examples of the joint portion. [Figure 6]2 is a cross-sectional view showing a state in which the seal ring shown in FIG. 1 is assembled to a shaft and a cylinder. FIG. [Figure 7] FIG. 4 is a plan view of a seal ring according to a second embodiment of the present invention. [Figure 8] 8 is a cross-sectional view of the seal ring shown in FIG. 7 taken along line BB'. [Figure 9] 8 is a cross-sectional view showing a state in which the seal ring shown in FIG. 7 is assembled to a movable scroll and a housing. [Figure 10] 8 is a partial perspective view showing a gap between the inner ring of the seal ring shown in FIG. 7. FIG. [Figure 11] FIG. 10 is a plan view of a seal ring according to a third embodiment of the present invention. [Figure 12] 12 is a cross-sectional view taken along line CC' of the seal ring shown in FIG. 11. FIG. [Figure 13] 12 is a cross-sectional view showing a state in which the seal ring shown in FIG. 11 is assembled to a movable scroll and a housing. FIG. [Figure 14] 12 is a partial perspective view showing a joint portion of an outer ring of the seal ring shown in FIG. 11. FIG. [Figure 15] FIG. 14 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 16] FIG. 14 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 17] 12 is a cross-sectional view showing a state in which the seal ring shown in FIG. 11 is assembled to a shaft and a cylinder. FIG. [Figure 18] FIG. 18 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 19] FIG. 18 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 20] FIG. 10 is a plan view of a seal ring according to a fourth embodiment of the present invention. [Figure 21] 21 is a cross-sectional view taken along line DD' of the seal ring shown in FIG. 20. FIG. [Figure 22] 21 is a cross-sectional view showing a state in which the seal ring shown in FIG. 20 is assembled to a movable scroll and a housing. FIG. [Figure 23]21 is a partial perspective view showing a gap between the inner ring of the seal ring shown in FIG. 20. FIG. [Figure 24] FIG. 23 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 25] FIG. 23 is a cross-sectional view of another embodiment of the configuration shown in FIG. [Figure 26] FIG. 10 is a plan view of a seal ring according to a fifth embodiment of the present invention. [Figure 27] FIG. 27 is a cross-sectional view taken along line EE' of the seal ring shown in FIG. 26. [Figure 28] FIG. 27 is a cross-sectional view showing a state in which the seal ring shown in FIG. 26 is assembled to the movable scroll and the housing. [Figure 29] FIG. 27 is a cross-sectional view showing a state in which the seal ring shown in FIG. 26 is assembled to a shaft and a cylinder. [Figure 30] FIG. 10 is a plan view of a seal ring according to a sixth embodiment of the present invention. [Figure 31] 31 is a cross-sectional view taken along line FF' of the seal ring shown in FIG. 30. FIG. [Figure 32] FIG. 31 is a cross-sectional view showing a state in which the seal ring shown in FIG. 30 is assembled to a movable scroll and a housing. [Figure 33] FIG. 11 is a plan view of a seal ring according to a seventh embodiment of the present invention. [Figure 34] FIG. 34 is a cross-sectional view taken along line GG' of the seal ring shown in FIG. 33. [Figure 35] FIG. 34 is a cross-sectional view showing a state in which the seal ring shown in FIG. 33 is assembled to the movable scroll and the housing. [Figure 36] FIG. 34 is a cross-sectional view showing a state in which the seal ring shown in FIG. 33 is assembled to a shaft and a cylinder. [Figure 37] FIG. 13 is a plan view of a seal ring according to an eighth embodiment of the present invention. [Figure 38] 38 is a cross-sectional view taken along line HH' of the seal ring shown in FIG. 37. [Figure 39] FIG. 38 is a cross-sectional view showing a state in which the seal ring shown in FIG. 37 is assembled to the movable scroll and the housing. [Figure 40] 10 is a graph showing the evaluation results of durability performance of the seal ring according to the example. [Figure 41] 10 is a graph showing the evaluation results of durability performance of the seal ring according to the example. DETAILED DESCRIPTION OF THE INVENTION

[0017] [Introduction] Embodiments of the present invention will be described with reference to the drawings. A seal ring according to one embodiment of the present invention can be used to seal the gap between a movable scroll and a housing in a scroll compressor, or between a shaft and a cylinder that reciprocate relative to one another. In any of the seal rings according to the embodiments, the fluid F to be sealed is a liquid or gas, and is typically a high-pressure liquid or gas, and the pressure of the fluid F to be sealed is expected to be 3 MPa or more and 30 MPa or less.

[0018] [First embodiment] A seal ring 100 according to a first embodiment of the present invention is configured to seal a fluid F on the inner circumferential side. FIG. 1 is a plan view of the seal ring 100. FIG. 2 is a cross-sectional view of the seal ring 100 taken along line A-A' in FIG. 1. The seal ring 100 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 2 is an axial cross section of the seal ring 100 taken along a plane including the central axis P. The seal ring 100 has an outer circumferential surface 101, an inner circumferential surface 102, a first side surface 103, and a second side surface 104.

[0019] The seal ring 100 has an outer ring 110 and an inner ring 120. The outer ring 110 and the inner ring 120 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0020] The outer ring 110 has a rectangular axial cross section and includes an outer ring outer peripheral surface 111, an outer ring inner peripheral surface 112, a first outer ring side surface 113, and a second outer ring side surface 114. The outer ring outer peripheral surface 111 is an outward-facing cylindrical surface extending in the axial direction. The outer ring inner peripheral surface 112 is an inward-facing cylindrical surface extending in the axial direction. The first outer ring side surface 113 and the second outer ring side surface 114 are both planes perpendicular to an axis parallel to the central axis P and face opposite each other. The outer ring outer peripheral surface 111 and the first outer ring side surface 113 of the outer ring 110 respectively constitute the outer peripheral surface 101 and the first side surface 103 of the seal ring 100.

[0021] The inner ring 120 has an L-shaped axial cross section and includes an inner ring inner circumferential surface 121 and an inner ring side surface 122. The inner ring inner circumferential surface 121 is an inward-facing cylindrical surface extending in the axial direction. The inner ring side surface 122 is a plane perpendicular to an axis parallel to the central axis P. The inner ring inner circumferential surface 121 and the inner ring side surface 122 of the inner ring 120 respectively constitute the inner circumferential surface 102 and the second side surface 104 of the seal ring 100. The inner ring 120 also has a first opposing surface 123 facing the outer circumferential side opposite the inner ring inner circumferential surface 121. The inner ring 120 also has a second opposing surface 124 perpendicular to an axis parallel to the central axis P and facing away from the inner ring side surface 122. In the seal ring 100, the first opposing surface 123 of the inner ring 120 contacts the outer ring inner surface 112 of the outer ring 110 in a radially opposed manner perpendicular to the central axis P, and the second opposing surface 124 of the inner ring 120 contacts the second outer ring side surface 114 of the outer ring 110 in an axially opposed manner.

[0022] In the seal ring 100, the axial dimension of the first opposing surface 123 of the inner ring 120 is smaller than the axial dimension of the outer ring inner peripheral surface 112 of the outer ring 110. Therefore, the axial end of the inner ring 120 opposite the inner ring side surface 122 is located axially more inward than the first outer ring side surface 113 of the outer ring 110. Therefore, in the seal ring 100, the inner ring 120 does not protrude from the first outer ring side surface 113 of the outer ring 110. Furthermore, in the seal ring 100, the radial dimension of the second opposing surface 124 of the inner ring 120 is smaller than the radial dimension of the second outer ring side surface 114 of the outer ring 110. Therefore, the outer peripheral end of the inner ring 120 is located more inward than the first outer ring side surface 113 of the outer ring 110. Therefore, in the seal ring 100, the inner ring 120 does not protrude from the outer ring outer peripheral surface 111 of the outer ring 110.

[0023] The outer ring 110 is formed of a resin harder than the inner ring 120. Specifically, the outer ring 110 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The inner ring 120 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0024] The axial and radial thicknesses of the outer ring 110 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the inner ring 120 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively.

[0025] 3 shows the seal ring 100 assembled to the movable scroll 140 and housing 150 of the scroll compressor. The seal ring 100 assembled to the movable scroll 140 and housing 150 is received in a groove 141 provided in the movable scroll 140, and seals the fluid F present on the inner periphery of the groove 141 in the gap between the movable scroll 140 and the housing 150 so as not to leak to the outer periphery of the groove 141. In the seal ring 100 assembled to the movable scroll 140 and housing 150, the first outer ring side surface 113 of the outer ring 110 protrudes slightly from the groove 141 of the movable scroll 140 toward the housing 150.

[0026] 3, in the seal ring 100 assembled to the movable scroll 140 and the housing 150, the outer ring outer peripheral surface 111 abuts against the side wall surface of the groove portion 141 of the movable scroll 140, and the first outer ring side surface 113 abuts against the housing 150. On the other hand, in the seal ring 100 assembled to the movable scroll 140 and the housing 150, the inner ring inner peripheral surface 121 is spaced apart from the side wall surface of the groove portion 141 of the movable scroll 140, and the inner ring side surface 122 is spaced apart from the groove bottom of the groove portion 141 of the movable scroll 140.

[0027] 1 to 3, the outer ring 110 is provided with a joint portion 130. The joint portion 130 has a first engagement portion 131 and a second engagement portion 132 that can be attached to and detached from each other. As a result, the outer ring 110 can be assembled to the groove portion 141 of the movable scroll 140 in an expanded diameter state as a whole by expanding the first engagement portion 131 and the second engagement portion 132 circumferentially at the joint portion 130. In the outer ring 110, the leakage amount of the fluid F at the joint portion 130 can be reduced by devising the shapes of the first engagement portion 131 and the second engagement portion 132.

[0028] Figure 4 is a partial perspective view showing the abutment 130 of the outer ring 110 from the outer ring outer peripheral surface 111 side. The abutment 130 shown in Figure 4 has a double-angle structure. The first engagement portion 131 has an outer inclined surface 131a facing the outer peripheral side that connects the outer ring outer peripheral surface 111 and the first outer ring side surface 113. The second engagement portion 132 has a rod shape with a right-angled triangular cross section, connects the outer ring outer peripheral surface 111 and the first outer ring side surface 113, and has an inner inclined surface 132a facing the inner peripheral side that faces the outer inclined surface 131a of the first engagement portion 131.

[0029] 3, in the seal ring 100 assembled to the movable scroll 140 and housing 150, at the joint 130 of the outer ring 110, the region of the outer ring outer peripheral surface 111 on the housing 150 side that seals the gap between the movable scroll 140 and the housing 150 is formed by the second engagement portion 132, and there is no axial gap that connects the outer peripheral region with the inner peripheral region. Therefore, in the seal ring 100, the amount of leakage of the fluid F at the joint 130 of the outer ring 110 can be reduced.

[0030] The seal ring 100 has high durability, which can prevent damage caused by stress from the high-pressure fluid F to be sealed, thanks to the outer ring 110 made of the hard first resin. Furthermore, the seal ring 100 has the outer ring 110, which forms the outer ring outer peripheral surface 111 that seals the gap between the movable scroll 140 and the housing 150, made of the hard first resin, thereby preventing creep deformation of the outer ring 110 from entering the gap between the movable scroll 140 and the housing 150. Therefore, the seal ring 100 is likely to maintain its ability to prevent leakage of the fluid F for a long period of time. To further enhance the seal ring 100's ability to prevent leakage of the fluid F, it is preferable that the axial dimension d of the region of the outer ring outer peripheral surface 111 of the outer ring 110 that contacts the side wall surface of the groove 141 of the movable scroll 140 be 0.2 mm or more.

[0031] Furthermore, in the seal ring 100, by using the inner ring 120 formed from the soft second resin, the adhesion between the outer ring inner circumferential surface 112 and the second outer ring side surface 114 of the outer ring 110 at the first opposing surface 123 and the second opposing surface 124 is improved. Therefore, in the seal ring 100, the fluid F is prevented from entering the region between the outer ring inner circumferential surface 112 and the first opposing surface 123, and the region between the second outer ring side surface 114 and the second opposing surface 124. As a result, the seal ring 100 achieves high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F, particularly at the joint portion 130 of the outer ring 110.

[0032] Furthermore, by using the inner ring 120 formed from the second soft resin in the seal ring 100, the axial cross section as a whole can be expanded. As a result, in the seal ring 100, the flow path of the fluid F in the groove portion 141 of the movable scroll 140 has a narrow and curved structure, so that the stress applied from the fluid F to the outer ring 110 is reduced. As a result, the seal ring 100 can more effectively suppress leakage of the fluid F.

[0033] The configuration of the seal ring 100 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 140 and the housing 150. For example, in the seal ring 100, the configuration of the butt joint 130 of the outer ring 110 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 100, butt joints may be provided not only in the outer ring 110 but also in the inner ring 120. The structure of the butt joint 130 of the outer ring 110 can be, in addition to a double angle, a straight structure as shown in FIG. 5(A), a step cut structure as shown in FIG. 5(B), an angled structure as shown in FIG. 5(C), or a triple step structure as shown in FIG. 5(D). In addition, the structure of the butt joint of the inner ring 120 can be, for example, a double angled structure, a straight structure, or an angled structure.

[0034] The seal ring 100 can also be used to seal a gap between a shaft and a cylinder that reciprocate relative to one another. Figure 6 shows the seal ring 100 assembled to a shaft 160 and a cylinder 170. The seal ring 100 assembled to the shaft 160 and the cylinder 170 is received in a groove 161 provided around the entire circumference of the shaft 160, and seals the gap between the shaft 160 and the cylinder 170 so that a fluid F on one side of the groove 161 in the direction along the central axis P of the groove 161 does not leak to the other side. In the seal ring 100 assembled to the shaft 160 and the cylinder 170, the outer peripheral surface 111 of the outer ring 110 protrudes slightly from the groove 161 of the shaft 160 toward the cylinder 170.

[0035] 6, in the seal ring 100 assembled to the shaft 160 and the cylinder 170, the outer ring outer peripheral surface 111 abuts against the cylinder 170, and the first outer ring side surface 113 abuts against the side wall surface of the groove portion 161 of the shaft 160. On the other hand, in the seal ring 100 assembled to the shaft 160 and the cylinder 170, the inner ring inner peripheral surface 121 is spaced apart from the groove bottom of the groove portion 161 of the shaft 160, and the inner ring side surface 122 is spaced apart from the side wall surface of the groove portion 161 of the shaft 160.

[0036] The seal ring 100 can effectively achieve the same effects as those achieved when sealing the gap between the movable scroll 140 and the housing 150, even when used to seal the gap between the shaft 160 and the cylinder 170. In order to further improve the seal ring 100's ability to prevent leakage of the fluid F, it is preferable that the radial dimension d of the area of ​​the first outer ring side surface 113 of the outer ring 110 that comes into contact with the side wall surface of the groove portion 141 of the movable scroll 140 be 0.2 mm or more.

[0037] [Second embodiment] A seal ring 200 according to the second embodiment of the present invention is configured to seal a fluid F on the outer periphery side. FIG. 7 is a plan view of the seal ring 200. FIG. 8 is a cross-sectional view of the seal ring 200 taken along line B-B' in FIG. 7. The seal ring 200 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 8 is an axial cross section of the seal ring 200 taken along a plane including the central axis P. The seal ring 200 has an outer peripheral surface 201, an inner peripheral surface 202, a first side surface 203, and a second side surface 204.

[0038] The seal ring 200 has an inner ring 210 and an outer ring 220. The inner ring 210 and the outer ring 220 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0039] The inner ring 210 has a rectangular axial cross section and includes an inner ring inner circumferential surface 211, an inner ring outer circumferential surface 212, a first inner ring side surface 213, and a second inner ring side surface 214. The inner ring inner circumferential surface 211 is an inward-facing cylindrical surface extending in the axial direction. The inner ring outer circumferential surface 212 is an outward-facing cylindrical surface extending in the axial direction. The first inner ring side surface 213 and the second inner ring side surface 214 are both planes perpendicular to an axis parallel to the central axis P and face opposite each other. The inner ring inner circumferential surface 211 and the first inner ring side surface 213 of the inner ring 210 respectively constitute the inner circumferential surface 202 and the second side surface 204 of the seal ring 200.

[0040] The outer ring 220 has an L-shaped axial cross section and includes an outer ring outer peripheral surface 221 and an outer ring side surface 222. The outer ring outer peripheral surface 221 is an outward-facing cylindrical surface extending in the axial direction. The outer ring side surface 222 is a plane perpendicular to an axis parallel to the central axis P. The outer ring outer peripheral surface 221 and the outer ring side surface 222 of the outer ring 220 respectively constitute the outer peripheral surface 201 and the first side surface 203 of the seal ring 200. The outer ring 220 also has a first opposing surface 223 facing the outer peripheral side opposite to the outer ring outer peripheral surface 221. The outer ring 220 also has a second opposing surface 224 perpendicular to an axis parallel to the central axis P and facing away from the outer ring side surface 222. In the seal ring 200, the first opposing surface 223 of the outer ring 220 contacts the inner ring outer peripheral surface 212 of the inner ring 210 in a radially opposed relationship perpendicular to the central axis P, and the second opposing surface 224 of the outer ring 220 contacts the second inner ring side surface 214 of the inner ring 210 in an axially opposed relationship.

[0041] In the seal ring 200, the axial dimension of the first opposing surface 223 of the outer ring 220 is smaller than the axial dimension of the inner ring outer peripheral surface 212 of the inner ring 210. Therefore, the axial end of the outer ring 220 opposite the outer ring side surface 222 is located axially more inward than the first inner ring side surface 213 of the inner ring 210. Therefore, in the seal ring 200, the outer ring 220 does not protrude from the first inner ring side surface 213 of the inner ring 210. Furthermore, in the seal ring 200, the radial dimension of the second opposing surface 224 of the outer ring 220 is smaller than the radial dimension of the second inner ring side surface 214 of the inner ring 210. Therefore, the inner peripheral end of the outer ring 220 is located more outer than the inner ring inner peripheral surface 211. Therefore, in the seal ring 200, the outer ring 220 does not protrude from the inner ring inner peripheral surface 211 of the inner ring 210.

[0042] The inner ring 210 is formed of a resin harder than the outer ring 220. Specifically, the inner ring 210 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The outer ring 220 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0043] The axial and radial thicknesses of the inner ring 210 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the outer ring 220 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively.

[0044] 9 shows a state in which the seal ring 200 is assembled to the movable scroll 240 and housing 250 of the scroll compressor. The seal ring 200 assembled to the movable scroll 240 and housing 250 is received in a groove 241 provided in the movable scroll 240, and seals the fluid F on the outer periphery side of the groove 241 in the gap between the movable scroll 240 and the housing 250 so as not to leak to the inner periphery side of the groove 241. In the seal ring 200 assembled to the movable scroll 240 and housing 250, the first inner ring side surface 213 of the inner ring 210 protrudes slightly from the groove 241 of the movable scroll 240 toward the housing 250.

[0045] 9 , in the seal ring 200 assembled to the movable scroll 240 and the housing 250, the inner ring inner peripheral surface 211 abuts against the side wall surface of the groove portion 241 of the movable scroll 240, and the first inner ring side surface 213 abuts against the housing 250. On the other hand, in the seal ring 200 assembled to the movable scroll 240 and the housing 250, the outer ring outer peripheral surface 221 is spaced apart from the side wall surface of the groove portion 241 of the movable scroll 240, and the outer ring side surface 222 is spaced apart from the groove bottom of the groove portion 241 of the movable scroll 240.

[0046] 7 to 9, the inner ring 210 is provided with a joint portion 230. The joint portion 230 has a first engagement portion 231 and a second engagement portion 232 that are mutually movable. As a result, the inner ring 210 can be assembled into the groove portion 241 of the movable scroll 240 in an expanded diameter state as a whole by expanding the first engagement portion 231 and the second engagement portion 232 circumferentially at the joint portion 230. In the inner ring 210, the amount of leakage of the fluid F at the joint portion 230 can be reduced by devising the shapes of the first engagement portion 231 and the second engagement portion 232.

[0047] Figure 10 is a partial perspective view showing the abutment 230 of the inner ring 210 from the inner ring inner circumferential surface 211 side. The abutment 230 shown in Figure 10 has a double-angle structure. The first engagement portion 231 has an inner inclined surface 231a facing the inner circumferential side that connects the inner ring inner circumferential surface 211 and the first inner ring side surface 213. The second engagement portion 232 has a rod shape with a right-angled triangular cross section, connects the inner ring inner circumferential surface 211 and the first inner ring side surface 213, and has an outer inclined surface 232a facing the outer circumferential side that faces the inner inclined surface 231a of the first engagement portion 231.

[0048] 9 , in the seal ring 200 assembled to the movable scroll 240 and housing 250, at the butt joint 230 of the inner ring 210, the region of the inner circumferential surface 211 of the inner ring facing the housing 250, which seals the gap between the movable scroll 240 and the housing 250, is defined by the second engagement portion 232, and no axial gap exists that connects the outer circumferential region with the inner circumferential region. Therefore, in the seal ring 200, the amount of leakage of the fluid F at the butt joint 230 of the inner ring 210 can be reduced.

[0049] The seal ring 200 has high durability, which can prevent damage caused by stress from the high-pressure fluid F to be sealed, due to the inner ring 210 formed from the hard first resin. Furthermore, the seal ring 200 has the inner ring 210, which forms the inner ring inner circumferential surface 211 that seals the gap between the movable scroll 240 and the housing 250, formed from the hard first resin, thereby preventing creep deformation of the inner ring 210 from entering the gap between the movable scroll 240 and the housing 250. Therefore, the seal ring 200 is likely to maintain its ability to prevent leakage of the fluid F for a long period of time. To further enhance the seal ring 200's ability to prevent leakage of the fluid F, it is preferable that the axial dimension d of the region of the inner ring inner circumferential surface 211 of the inner ring 210 that contacts the side wall surface of the groove 241 of the movable scroll 240 be 0.2 mm or more.

[0050] Furthermore, in the seal ring 200, by using the outer ring 220 formed from the second soft resin, the adhesion between the first opposing surface 223 and the second opposing surface 224 and the inner ring outer peripheral surface 212 and the second inner ring side surface 214 of the inner ring 210 is improved. Therefore, in the seal ring 200, the fluid F is prevented from entering the region between the inner ring outer peripheral surface 212 and the first opposing surface 223 and the region between the second inner ring side surface 214 and the second opposing surface 224. As a result, the seal ring 200 achieves high leakage prevention performance against the fluid F, and can effectively prevent leakage of the fluid F particularly from the joint portion 230 of the inner ring 210.

[0051] Furthermore, in the seal ring 200, by using the outer ring 220 formed from the second soft resin, the axial cross section as a whole can be expanded. As a result, in the seal ring 200, the flow path of the fluid F in the groove portion 241 of the movable scroll 240 has a narrow and curved structure, so that the stress applied from the fluid F to the inner ring 210 is reduced. As a result, in the seal ring 200, leakage of the fluid F can be suppressed more effectively.

[0052] The configuration of the seal ring 200 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 240 and the housing 250. For example, in the seal ring 200, the configuration of the butt joint 230 of the inner ring 210 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 200, butt joints may be provided not only in the inner ring 210 but also in the outer ring 220. The structure of the butt joint 230 of the inner ring 210 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the outer ring 220 can be, for example, double angled, straight, angled, or the like.

[0053] [Third embodiment] A seal ring 300 according to the third embodiment of the present invention is configured to seal a fluid F on the inner circumferential side. FIG. 11 is a plan view of the seal ring 300. FIG. 12 is a cross-sectional view of the seal ring 300 taken along line CC' in FIG. 11. The seal ring 300 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 12 is an axial cross section of the seal ring 300 taken along a plane including the central axis P. The seal ring 300 has an outer circumferential surface 301, an inner circumferential surface 302, a first side surface 303, and a second side surface 304.

[0054] The seal ring 300 has an outer ring 310 and an inner ring 320. The outer ring 310 and the inner ring 320 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0055] The outer ring 310 has an outer ring outer peripheral surface 311, an outer ring side surface 312, and an inner tapered surface 313. The outer ring outer peripheral surface 311 of the outer ring 310 is an outward-facing cylindrical surface extending in the axial direction. The outer ring side surface 312 of the outer ring 310 is a plane extending inward from the end of the outer ring outer peripheral surface 311 and perpendicular to an axis parallel to the central axis P. The inner tapered surface 313 of the outer ring 310 is an inclined surface facing inward, inclined with respect to the outer ring outer peripheral surface 311 and the outer ring side surface 312, and formed with a gap between them. The outer ring outer peripheral surface 311 and the outer ring side surface 312 of the outer ring 310 respectively constitute the outer peripheral surface 301 and the first side surface 303 of the seal ring 300.

[0056] The inner ring 320 has an inner ring inner circumferential surface 321, an inner ring side surface 322, and an outer tapered surface 323. The inner ring inner circumferential surface 321 of the inner ring 320 is an outward-facing cylindrical surface extending in the axial direction. The inner ring side surface 322 of the inner ring 320 is a plane extending inward from the end of the inner ring inner circumferential surface 321 and perpendicular to an axis parallel to the central axis P. The outer tapered surface 323 of the inner ring 320 is an inclined surface facing outward, inclined with respect to the inner ring inner circumferential surface 321 and the inner ring side surface 322, and formed with a gap between them. The inner ring inner circumferential surface 321 and the inner ring side surface 322 of the inner ring 320 respectively constitute the inner circumferential surface 302 and the second side surface 304 of the seal ring 300.

[0057] In seal ring 300, inner tapered surface 313 of outer ring 310 and outer tapered surface 323 of inner ring 320 face each other and are in contact with each other. Furthermore, in seal ring 300, angle α formed between outer ring outer peripheral surface 311 and inner tapered surface 313 of outer ring 310 is equal to angle β formed between inner ring inner peripheral surface 321 and outer tapered surface 323 of inner ring 320. Therefore, in seal ring 300, outer ring outer peripheral surface 311 of outer ring 310 and inner ring inner peripheral surface 321 of inner ring 320 face each other in the radial direction perpendicular to central axis P, and outer ring side surface 312 of outer ring 310 and inner ring side surface 322 of inner ring 320 face each other in the axial direction.

[0058] In the seal ring 300, the axial end of the inner ring 320 opposite the inner ring side surface 322 is located axially inward of the outer ring side surface 312 of the outer ring 310. Therefore, in the seal ring 300, the inner ring 320 does not protrude from the outer ring side surface 312 of the outer ring 310. Also, in the seal ring 300, the outer peripheral end of the inner ring 320 is located inner than the outer ring outer peripheral surface 311. Therefore, in the seal ring 300, the inner ring 320 does not protrude from the outer ring outer peripheral surface 311 of the outer ring 310.

[0059] The outer ring 310 is formed of a resin harder than the inner ring 320. Specifically, the outer ring 310 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The inner ring 320 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0060] The maximum axial and radial thicknesses of the outer ring 310 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the inner ring 320 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively.

[0061] 13 shows a state in which the seal ring 300 is assembled to the movable scroll 340 and housing 350 of the scroll compressor. The seal ring 300 assembled to the movable scroll 340 and housing 350 is received in a groove 341 provided in the movable scroll 340, and seals the fluid F on the inner circumferential side of the groove 341 in the gap between the movable scroll 340 and the housing 350 so as not to leak to the outer circumferential side of the groove 341. In the seal ring 300 assembled to the movable scroll 340 and housing 350, the outer ring side surface 312 of the outer ring 310 protrudes slightly from the groove 341 of the movable scroll 340 toward the housing 350.

[0062] 13 , in the seal ring 300 assembled to the movable scroll 340 and the housing 350, the outer ring outer peripheral surface 311 abuts against the side wall surface of the groove portion 341 of the movable scroll 340, and the outer ring side surface 312 abuts against the housing 350. On the other hand, in the seal ring 300 assembled to the movable scroll 340 and the housing 350, the inner ring inner peripheral surface 321 is spaced apart from the side wall surface of the groove portion 341 of the movable scroll 340, and the inner ring side surface 322 is spaced apart from the groove bottom of the groove portion 341 of the movable scroll 340.

[0063] 11 to 13, the outer ring 310 is provided with a joint portion 330. The joint portion 330 has a first engagement portion 331 and a second engagement portion 332 that are mutually movable. As a result, the outer ring 310 can be assembled into the groove portion 341 of the movable scroll 340 in an expanded diameter state as a whole by expanding the first engagement portion 331 and the second engagement portion 332 circumferentially at the joint portion 330. In the outer ring 310, the leakage amount of the fluid F at the joint portion 330 can be reduced by devising the shapes of the first engagement portion 331 and the second engagement portion 332.

[0064] Figure 14 is a partial perspective view showing the abutment 330 of the outer ring 310 from the outer ring outer peripheral surface 311 side. The abutment 330 shown in Figure 14 has a double-angle structure. The first engagement portion 331 has an outer inclined surface 331a facing the outer periphery that connects the outer ring outer peripheral surface 311 and the outer ring side surface 312. The second engagement portion 332 is rod-shaped with a right-angled triangular cross section, connects the outer ring outer peripheral surface 311 and the outer ring side surface 312, and has an inner inclined surface 332a facing the inner periphery that faces the outer inclined surface 331a of the first engagement portion 331.

[0065] 13 , in the seal ring 300 assembled to the movable scroll 340 and housing 350, at the joint 330 of the outer ring 310, the region of the outer ring outer peripheral surface 311 facing the housing 350, which seals the gap between the movable scroll 340 and the housing 350, is formed by the second engagement portion 332, and no axial gap exists that connects the outer peripheral region with the inner peripheral region. Therefore, in the seal ring 300, the amount of leakage of the fluid F at the joint 330 of the outer ring 310 can be reduced.

[0066] The seal ring 300 has high durability, which can prevent damage due to stress from the high-pressure fluid F to be sealed, thanks to the outer ring 310 made of the hard first resin. Furthermore, the seal ring 300 has the outer ring 310, which forms the outer ring outer peripheral surface 311 that seals the gap between the movable scroll 340 and the housing 350, made of the hard first resin. This prevents creep deformation of the outer ring 310 from entering the gap between the movable scroll 340 and the housing 350. Therefore, the seal ring 300 is likely to maintain its ability to prevent leakage of the fluid F for a long period of time. To further enhance the seal ring 300's ability to prevent leakage of the fluid F, it is preferable that the axial dimension d of the region of the outer ring outer peripheral surface 311 of the outer ring 310 that contacts the side wall surface of the groove 341 of the movable scroll 340 be 0.2 mm or more.

[0067] Furthermore, in the seal ring 300, by using the inner ring 320 formed from the soft second resin, the adhesion of the outer tapered surface 323 of the inner ring 320 to the inner tapered surface 313 of the outer ring 310 is improved. Therefore, in the seal ring 300, the fluid F is prevented from entering the region between the inner tapered surface 313 of the outer ring 310 and the outer tapered surface 323 of the inner ring 320. As a result, the seal ring 300 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F particularly from the joint portion 330 of the outer ring 310.

[0068] Furthermore, by using the inner ring 320 made of a soft second resin in the seal ring 300, the axial cross section as a whole can be expanded. As a result, in the seal ring 300, the flow path of the fluid F in the groove portion 341 of the movable scroll 340 has a narrow and curved structure, so that the stress applied from the fluid F to the outer ring 310 is reduced. As a result, the seal ring 300 can more effectively suppress leakage of the fluid F.

[0069] The configuration of the seal ring 300 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 340 and the housing 350. For example, in the seal ring 300, the configuration of the butt joint 330 of the outer ring 310 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 300, butt joints may be provided not only in the outer ring 310 but also in the inner ring 320. The structure of the butt joint 330 of the outer ring 310 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the inner ring 320 can be, for example, double angled, straight, angled, or the like.

[0070] 15, the seal ring 300 may be assembled to the movable scroll 340 and the housing 350 with the inner ring side surface 322 of the inner ring 320 in contact with the bottom surface of the groove 341 of the movable scroll 340. In the seal ring 300 in the state shown in FIG. 15, the outer ring side surface 312 of the outer ring 310 receives a pressing force from the housing 350, and the inner ring side surface 322 of the inner ring 320 receives a pressing force from the groove bottom of the groove 341 of the movable scroll 340, so that the inner ring 320, which is softer than the outer ring 310, is sandwiched between the housing 350 and the inner tapered surface 313 of the outer ring 310 and is compressed and deformed in the axial direction.

[0071] 15, the compressive force of the inner ring 320 causes the outer ring side surface 312 of the outer ring 310 to tightly adhere to the housing 350. Furthermore, in the seal ring 300, the pressing force that the outer ring 310 receives from the outer tapered surface 323 of the inner ring 320 at the inner tapered surface 313 has a component in the outer circumferential direction, so the outer ring outer circumferential surface 311 tightly adheres to the side wall surface of the groove portion 341 of the movable scroll 340. Therefore, by tightly sealing the gap between the movable scroll 340 and the housing 350, the seal ring 300 can significantly reduce the amount of leakage to the inner circumferential side, even of a low-viscosity fluid F such as a gas.

[0072] The axial dimension of seal ring 300 before assembly to movable scroll 340 and housing 350 is preferably 1.05 to 1.20 times the distance between housing 350 and the bottom of groove portion 341 provided in movable scroll 340. This allows seal ring 300 to more effectively obtain the above-mentioned effect of the compressive force of inner ring 320 while ensuring good assembly properties.

[0073] The seal ring 300 does not have to be configured so that the inner ring side surface 322 of the inner ring 320 is in direct contact with the bottom surface of the groove 341 of the movable scroll 340, and may be configured so that an elastic member S is sandwiched between the inner ring side surface 322 of the inner ring 320 and the bottom surface of the groove 341 of the movable scroll 340, as shown in Fig. 16. In this case, the seal ring 300 also has the same effect as in the state shown in Fig. 15. As the elastic member S, for example, a coil expander or a wave washer can be used.

[0074] The seal ring 300 can also be used to seal a gap between a shaft and a cylinder that reciprocate relative to one another. Figure 17 shows the seal ring 300 assembled to a shaft 360 and a cylinder 370. The seal ring 300 assembled to the shaft 360 and the cylinder 370 is received in a groove 361 provided around the entire circumference of the shaft 360, and seals the gap between the shaft 360 and the cylinder 370 so that fluid F on one side of the groove 361 in the direction along the central axis P of the groove 361 does not leak to the other side. In the seal ring 300 assembled to the shaft 360 and the cylinder 370, the outer ring outer surface 311 of the outer ring 310 protrudes slightly from the groove 361 of the shaft 360 toward the cylinder 370.

[0075] 17 , in the seal ring 300 assembled to the shaft 360 and the cylinder 370, the outer ring outer peripheral surface 311 abuts against the cylinder 370, and the outer ring side surface 312 abuts against the side wall surface of the groove portion 361 of the shaft 360. On the other hand, in the seal ring 300 assembled to the shaft 360 and the cylinder 370, the inner ring inner peripheral surface 321 is spaced apart from the groove bottom of the groove portion 361 of the shaft 360, and the inner ring side surface 322 is spaced apart from the side wall surface of the groove portion 361 of the shaft 360.

[0076] The seal ring 300 effectively achieves the same effects as those achieved when sealing the gap between the movable scroll 340 and the housing 350, even when used to seal the gap between the shaft 360 and the cylinder 370. In order to further improve the seal ring 300's ability to prevent leakage of the fluid F, it is preferable that the radial dimension d of the region of the outer ring side surface 312 of the outer ring 310 that comes into contact with the side wall surface of the groove portion 361 of the shaft 360 be 0.2 mm or more.

[0077] 18, the seal ring 300 may be assembled to the shaft 360 and the cylinder 370 with the inner ring side surface 322 of the inner ring 320 in contact with the side wall surface of the groove 361 of the shaft 360. In the seal ring 300 in the state shown in FIG. 18, the outer ring side surface 312 of the outer ring 310 receives a pressing force from one side wall surface of the groove 361 of the shaft 360, and the inner ring side surface 322 of the inner ring 320 receives a pressing force from the other side wall surface of the groove 361 of the shaft 360, so that the inner ring 320, which is softer than the outer ring 310, is sandwiched between the shaft 360 and the inner tapered surface 313 of the outer ring 310 and is compressed and deformed in the axial direction.

[0078] 18, the compressive force of the inner ring 320 causes the outer ring side surface 312 of the outer ring 310 to tightly adhere to the side wall surface of the groove 361 of the shaft 360. Also, in the seal ring 300, the pressing force that the outer ring 310 receives from the outer tapered surface 323 of the inner ring 320 at the inner tapered surface 313 has an axial component toward the cylinder 370, so the outer ring outer peripheral surface 311 tightly adheres to the cylinder 370. Therefore, by tightly sealing the gap between the shaft 360 and the cylinder 370, the seal ring 300 can significantly reduce the amount of leakage to the inner periphery, even of a low-viscosity fluid F such as a gas.

[0079] The axial dimension of seal ring 300 before being assembled to shaft 360 and cylinder 370 is preferably 1.05 to 1.20 times the distance between both side wall surfaces of groove portion 361 of shaft 360. This allows seal ring 300 to more effectively obtain the above-mentioned effect of the compressive force of inner ring 320 while ensuring good assembly properties.

[0080] The seal ring 300 does not have to be configured so that the inner ring side surface 322 of the inner ring 320 is in direct contact with the side wall surface of the groove 361 of the shaft 360, and may be configured so that an elastic member S is sandwiched between the inner ring side surface 322 of the inner ring 320 and the side wall surface of the groove 361 of the shaft 360, as shown in Fig. 19. In this case, the seal ring 300 also has the same effect as in the state shown in Fig. 18. As the elastic member S, for example, a coil expander or a wave washer can be used.

[0081] [Fourth embodiment] A seal ring 400 according to a fourth embodiment of the present invention is configured to seal a fluid F on the outer periphery side. FIG. 20 is a plan view of the seal ring 400. FIG. 21 is a cross-sectional view of the seal ring 400 taken along line D-D' in FIG. 20. The seal ring 400 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 21 is an axial cross section taken along a plane including the central axis P of the seal ring 400. The seal ring 400 has an outer periphery surface 401, an inner periphery surface 402, a first side surface 403, and a second side surface 404.

[0082] The seal ring 400 has an inner ring 410 and an outer ring 420. The inner ring 410 and the outer ring 420 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0083] The inner ring 410 has an inner ring inner circumferential surface 411, an inner ring side surface 412, and an outer tapered surface 413. The inner ring inner circumferential surface 411 of the inner ring 410 is an inward-facing cylindrical surface extending in the axial direction. The inner ring side surface 412 of the inner ring 410 is a plane extending inward from the end of the inner ring inner circumferential surface 411 and perpendicular to an axis parallel to the central axis P. The outer tapered surface 413 of the inner ring 410 is an inclined surface facing outward, inclined with respect to the inner ring inner circumferential surface 411 and the inner ring side surface 412, and formed with a gap between them. The inner ring inner circumferential surface 411 and the inner ring side surface 412 of the inner ring 410 respectively constitute the inner circumferential surface 402 and the second side surface 404 of the seal ring 400.

[0084] The outer ring 420 has an outer ring outer peripheral surface 421, an outer ring side surface 422, and an inner tapered surface 423. The outer ring outer peripheral surface 421 of the outer ring 420 is an inward-facing cylindrical surface extending in the axial direction. The outer ring side surface 422 of the outer ring 420 is a plane extending from the end of the outer ring outer peripheral surface 421 toward the inner peripheral side and perpendicular to an axis parallel to the central axis P. The inner tapered surface 423 of the outer ring 420 is an inclined surface facing the inner peripheral side, inclined with respect to the outer ring outer peripheral surface 421 and the outer ring side surface 422, and formed with a gap between them. The outer ring outer peripheral surface 421 and the outer ring side surface 422 of the outer ring 420 respectively constitute the outer peripheral surface 401 and the first side surface 403 of the seal ring 400.

[0085] In the seal ring 400, the outer tapered surface 413 of the inner ring 410 and the inner tapered surface 423 of the outer ring 420 face each other and are in contact with each other. Furthermore, in the seal ring 400, the angle α formed between the inner ring inner circumferential surface 411 and the outer tapered surface 413 of the inner ring 410 is equal to the angle β formed between the outer ring outer circumferential surface 421 and the inner tapered surface 423 of the outer ring 420. Therefore, in the seal ring 400, the inner ring inner circumferential surface 411 of the inner ring 410 and the outer ring outer circumferential surface 421 of the outer ring 420 face each other in the radial direction perpendicular to the central axis P, and the inner ring side surface 412 of the inner ring 410 and the outer ring side surface 422 of the outer ring 420 face each other in the axial direction.

[0086] In the seal ring 400, the axial end of the outer ring 420 opposite the outer ring side surface 422 is located axially inward of the inner ring side surface 412 of the inner ring 410. Therefore, in the seal ring 400, the outer ring 420 does not protrude from the inner ring side surface 412 of the inner ring 410. Also, in the seal ring 400, the inner circumferential end of the outer ring 420 is located more inward than the inner ring inner circumferential surface 411. Therefore, in the seal ring 400, the outer ring 420 does not protrude from the inner ring inner circumferential surface 411 of the inner ring 410.

[0087] The inner ring 410 is formed of a resin harder than the outer ring 420. Specifically, the inner ring 410 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The outer ring 420 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0088] The maximum axial and radial thicknesses of the inner ring 410 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the outer ring 420 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively.

[0089] 22 shows a state in which the seal ring 400 is assembled to the movable scroll 440 and housing 450 of the scroll compressor. The seal ring 400 assembled to the movable scroll 440 and housing 450 is received in a groove 441 provided in the movable scroll 440, and seals the fluid F on the outer periphery side of the groove 441 in the gap between the movable scroll 440 and the housing 450 so as not to leak to the inner periphery side of the groove 441. In the seal ring 400 assembled to the movable scroll 440 and housing 450, the inner ring side surface 412 of the inner ring 410 protrudes slightly from the groove 441 of the movable scroll 440 toward the housing 450.

[0090] 22 , in the seal ring 400 assembled to the movable scroll 440 and the housing 450, the inner ring inner peripheral surface 411 abuts against the side wall surface of the groove portion 441 of the movable scroll 440, and the inner ring side surface 412 abuts against the housing 450. On the other hand, in the seal ring 400 assembled to the movable scroll 440 and the housing 450, the outer ring outer peripheral surface 421 is spaced apart from the side wall surface of the groove portion 441 of the movable scroll 440, and the outer ring side surface 422 is spaced apart from the groove bottom of the groove portion 441 of the movable scroll 440.

[0091] 20 to 22, the inner ring 410 is provided with a joint 430. The joint 430 has a first engagement portion 431 and a second engagement portion 432 that can be attached to and detached from each other. As a result, the inner ring 410 can be assembled into the groove 441 of the movable scroll 440 in an expanded diameter state as a whole by expanding the first engagement portion 431 and the second engagement portion 432 circumferentially at the joint 430. In the inner ring 410, the amount of leakage of the fluid F at the joint 430 can be reduced by devising the shapes of the first engagement portion 431 and the second engagement portion 432.

[0092] Figure 23 is a partial perspective view showing the abutment 430 of the inner ring 410 from the inner ring inner circumferential surface 411 side. The abutment 430 shown in Figure 23 has a double-angle structure. The first engagement portion 431 has an inner inclined surface 431a facing the inner circumferential side that connects the inner ring inner circumferential surface 411 and the inner ring side surface 412. The second engagement portion 432 has a rod shape with a right-angled triangular cross section, connects the inner ring inner circumferential surface 411 and the inner ring side surface 412, and has an outer inclined surface 432a facing the outer circumferential side that faces the inner inclined surface 431a of the first engagement portion 431.

[0093] 22 , in the seal ring 400 assembled to the movable scroll 440 and housing 450, at the joint 430 of the inner ring 410, the region of the inner circumferential surface 411 of the inner ring that seals the gap between the movable scroll 440 and the housing 450 is formed by the second engagement portion 432, and there is no axial gap that connects the outer circumferential region with the inner circumferential region. Therefore, in the seal ring 400, the amount of leakage of the fluid F at the joint 430 of the inner ring 410 can be reduced.

[0094] The seal ring 400 has high durability, which can prevent damage due to stress from the high-pressure fluid F to be sealed, thanks to the inner ring 410 made of the hard first resin. Furthermore, the seal ring 400 has the inner ring 410, which forms the inner ring inner circumferential surface 411 that seals the gap between the movable scroll 440 and the housing 450, made of the hard first resin. This prevents creep deformation of the inner ring 410 from entering the gap between the movable scroll 440 and the housing 450. Therefore, the seal ring 400 is likely to maintain its ability to prevent leakage of the fluid F for a long period of time. To further enhance the seal ring 400's ability to prevent leakage of the fluid F, it is preferable that the axial dimension d of the region of the inner ring inner circumferential surface 411 of the inner ring 410 that contacts the side wall surface of the groove 441 of the movable scroll 440 be 0.2 mm or more.

[0095] Furthermore, in the seal ring 400, by using the outer ring 420 formed from the soft second resin, the adhesion of the inner tapered surface 423 of the outer ring 420 to the outer tapered surface 413 of the inner ring 410 is improved. Therefore, in the seal ring 400, the fluid F is prevented from entering the region between the outer tapered surface 413 of the inner ring 410 and the inner tapered surface 423 of the outer ring 420. As a result, the seal ring 400 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F particularly from the joint portion 430 of the inner ring 410.

[0096] Furthermore, by using the outer ring 420 made of a soft second resin in the seal ring 400, the axial cross section as a whole can be expanded. As a result, in the seal ring 400, the flow path of the fluid F in the groove portion 441 of the movable scroll 440 has a narrow and curved structure, so that the stress applied from the fluid F to the inner ring 410 is reduced. As a result, in the seal ring 400, leakage of the fluid F can be suppressed more effectively.

[0097] The configuration of the seal ring 400 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 440 and the housing 450. For example, in the seal ring 400, the configuration of the butt joint 430 of the inner ring 410 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 400, butt joints may be provided not only in the inner ring 410 but also in the outer ring 420. The structure of the butt joint 430 of the inner ring 410 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the outer ring 420 can be, for example, double angled, straight, angled, or the like.

[0098] 24, the seal ring 400 may be assembled to the movable scroll 440 and the housing 450 in a state in which the outer ring side surface 422 of the outer ring 420 abuts against the bottom surface of the groove portion 441 of the movable scroll 440. In the seal ring 400 in the state shown in FIG. 24, the inner ring side surface 412 of the inner ring 410 receives a pressing force from the housing 450, and the outer ring side surface 422 of the outer ring 420 receives a pressing force from the groove bottom of the groove portion 441 of the movable scroll 440, so that the outer ring 420, which is softer than the inner ring 410, is sandwiched between the housing 450 and the outer tapered surface 413 of the inner ring 410 and is compressed and deformed in the axial direction.

[0099] 24, the compressive force of the outer ring 420 causes the inner ring side surface 412 of the inner ring 410 to tightly adhere to the housing 450. Furthermore, in the seal ring 400, the pressing force that the inner ring 410 receives at its outer tapered surface 413 from the inner tapered surface 423 of the outer ring 420 has an inner circumferential component, so the inner ring inner circumferential surface 411 tightly adheres to the side wall surface of the groove portion 441 of the movable scroll 440. Therefore, the seal ring 400 tightly seals the gap between the movable scroll 440 and the housing 450, thereby significantly reducing the amount of leakage to the inner circumferential side, even of a low-viscosity fluid F such as a gas.

[0100] The axial dimension of seal ring 400 before assembly to movable scroll 440 and housing 450 is preferably 1.05 to 1.20 times the distance between the housing 450 and the groove bottom of groove portion 441 provided in movable scroll 440. This allows seal ring 400 to more effectively obtain the above-mentioned effect of the compressive force of outer ring 420 while ensuring good assembly properties.

[0101] The seal ring 400 does not have to be configured so that the outer ring side surface 422 of the outer ring 420 directly contacts the bottom surface of the groove portion 441 of the movable scroll 440, and may be configured so that an elastic member S is sandwiched between the outer ring side surface 422 of the outer ring 420 and the bottom surface of the groove portion 441 of the movable scroll 440, as shown in Fig. 25. In this case, the seal ring 400 can also achieve the same effect as in the state shown in Fig. 24. As the elastic member S, for example, a coil expander or a wave washer can be used.

[0102] [Fifth embodiment] A seal ring 500 according to a fifth embodiment of the present invention is configured to seal a fluid F on the inner circumferential side. FIG. 26 is a plan view of the seal ring 500. FIG. 27 is a cross-sectional view of the seal ring 500 taken along line E-E' in FIG. 26. The seal ring 500 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 27 is an axial cross section of the seal ring 500 taken along a plane including the central axis P. The seal ring 500 has an outer circumferential surface 501, an inner circumferential surface 502, a first side surface 503, and a second side surface 504.

[0103] The seal ring 500 has an outer ring 510 and an inner ring 520. The outer ring 510 and the inner ring 520 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0104] The outer ring 510 has a rectangular axial cross section and includes an outer ring outer peripheral surface 511, an outer ring inner peripheral surface 512, a first outer ring side surface 513, and a second outer ring side surface 514. The outer ring outer peripheral surface 511 is an outward-facing cylindrical surface extending in the axial direction. The outer ring inner peripheral surface 512 is an inward-facing cylindrical surface extending in the axial direction. The first outer ring side surface 513 and the second outer ring side surface 514 are both planes perpendicular to an axis parallel to the central axis P and face opposite each other. The outer ring outer peripheral surface 511 and the first outer ring side surface 513 of the outer ring 510 respectively constitute the outer peripheral surface 501 and the first side surface 503 of the seal ring 500.

[0105] The inner ring 520 has an L-shaped axial cross section and includes an inner ring inner circumferential surface 521 and an inner ring side surface 522. The inner ring inner circumferential surface 521 is an inward-facing cylindrical surface extending in the axial direction. The inner ring side surface 522 is a plane perpendicular to an axis parallel to the central axis P. The inner ring inner circumferential surface 521 and the inner ring side surface 522 of the inner ring 520 respectively constitute the inner circumferential surface 502 and the second side surface 504 of the seal ring 500. The inner ring 520 also has a first opposing surface 523 facing the outer circumferential side opposite the inner ring inner circumferential surface 521. The inner ring 520 also has a second opposing surface 524 perpendicular to an axis parallel to the central axis P and facing away from the inner ring side surface 522. In the seal ring 500, the first opposing surface 523 of the inner ring 520 faces the outer ring inner surface 512 of the outer ring 510 in a radial direction perpendicular to the central axis P, and the second opposing surface 524 of the inner ring 520 faces the second outer ring side surface 514 of the outer ring 510 in the axial direction.

[0106] The inner ring 520 further has an outer peripheral end surface 525 and a side end surface 526. The outer peripheral end surface 525 is an outwardly facing cylindrical surface extending in the axial direction, connecting the inner ring side surface 522 and the second opposing surface 524, and constituting the outer peripheral end of the inner ring 520. The side end surface 526 is a plane that connects the inner ring inner peripheral surface 521 and the first opposing surface 523, and constitutes the axial end of the inner ring 520 opposite the inner ring side surface 522, and is perpendicular to an axis parallel to the central axis P. The outer peripheral end surface 525 of the inner ring 520, together with the outer ring outer peripheral surface 511 of the outer ring 510, constitutes the outer peripheral surface 501 of the seal ring 500. The side end surface 526 of the inner ring 520, together with the first outer ring side surface 513 of the outer ring 510, constitutes the first side surface 503 of the seal ring 500.

[0107] In the seal ring 500, the axial dimension of the first opposing surface 523 of the inner ring 520 is larger than the axial dimension of the outer ring inner peripheral surface 512 of the outer ring 510. Therefore, the side end surface 526 of the inner ring 520 is located axially outward from the first outer ring side surface 513 of the outer ring 510. Therefore, in the seal ring 500, the inner ring 520 protrudes from the first outer ring side surface 513 of the outer ring 510. Furthermore, in the seal ring 500, the radial dimension of the second opposing surface 524 of the inner ring 520 is larger than the radial dimension of the second outer ring side surface 514 of the outer ring 510. Therefore, the outer peripheral end surface 525 of the inner ring 520 is located outer than the first outer ring side surface 513 of the outer ring 510. Therefore, in the seal ring 500, the inner ring 520 protrudes from the outer ring outer peripheral surface 511 of the outer ring 510.

[0108] The outer ring 510 is formed of a resin harder than the inner ring 520. Specifically, the outer ring 510 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The inner ring 520 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0109] The axial and radial thicknesses of the outer ring 510 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the inner ring 520 can be, for example, 1.2 mm or more and 5.5 mm or less, respectively.

[0110] 28 shows a state in which the seal ring 500 is assembled to the movable scroll 540 and housing 550 of the scroll compressor. The seal ring 500 assembled to the movable scroll 540 and housing 550 is received in a groove 541 provided in the movable scroll 540, and seals the fluid F on the inner periphery side of the groove 541 in the gap between the movable scroll 540 and the housing 550 so as not to leak to the outer periphery side of the groove 541. In the seal ring 500 assembled to the movable scroll 540 and housing 550, the side end surface 526 of the inner ring 520 protrudes slightly from the groove 541 of the movable scroll 540 toward the housing 550.

[0111] 28 , in the seal ring 500 assembled to the movable scroll 540 and the housing 550, the outer peripheral end surface 525 of the inner ring 520 abuts against the side wall surface of the groove portion 541 of the movable scroll 540, and the side end surface 526 of the inner ring 520 abuts against the housing 550. In addition, in the seal ring 500 assembled to the movable scroll 540 and the housing 550, the outer ring 510 is located in a space surrounded by the opposing surfaces 523, 524 of the inner ring 520, the movable scroll 540, and the housing 550. The outer ring 510 may be spaced apart from at least one of the opposing surfaces 523, 524 of the inner ring 520, the movable scroll 540, and the housing 550.

[0112] 26 to 28, the outer ring 510 is provided with a joint portion 530. The joint portion 530 has a first engagement portion 531 and a second engagement portion 532 that are mutually movable. As a result, the outer ring 510 can be assembled into the groove portion 541 of the movable scroll 540 in an expanded diameter state as a whole by expanding the first engagement portion 531 and the second engagement portion 532 circumferentially at the joint portion 530. The joint portion 530 of the outer ring 510 is configured similarly to the joint portion 130 of the outer ring 110 of the seal ring 100 according to the first embodiment shown in FIGS. 1 to 4.

[0113] In the seal ring 500, the outer ring 510 formed from the hard first resin provides high durability that can prevent damage caused by stress from the high-pressure fluid F that is the object of sealing. In addition, in the seal ring 500, the outer ring 510 adjacent to the gap between the movable scroll 540 and the housing 550 is formed from the hard first resin, thereby preventing creep deformation of the outer ring 510 from entering the gap between the movable scroll 540 and the housing 550.

[0114] Furthermore, in the seal ring 500, by using the inner ring 520 formed from the soft second resin, the adhesion of the outer peripheral end surface 525 and the side end surface 526 of the inner ring 520 to the movable scroll 540 and the housing 550 is improved. Therefore, in the seal ring 500, the fluid F is prevented from entering the region between the outer peripheral end surface 525 of the inner ring 520 and the movable scroll 540, and the region between the side end surface 526 of the inner ring 520 and the housing 550. As a result, the seal ring 500 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F, particularly from the butt portion 530 of the outer ring 510.

[0115] The configuration of the seal ring 500 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 540 and the housing 550. For example, in the seal ring 500, the configuration of the butt joint 530 of the outer ring 510 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 500, butt joints may be provided not only in the outer ring 510 but also in the inner ring 520. The structure of the butt joint 530 of the outer ring 510 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the inner ring 520 can be, for example, double angled, straight, angled, or the like.

[0116] The seal ring 500 can also be used to seal a gap between a shaft and a cylinder that reciprocate relative to one another. Figure 29 shows the seal ring 500 assembled to a shaft 560 and a cylinder 570. The seal ring 500 assembled to the shaft 560 and the cylinder 570 is received in a groove 561 provided around the entire circumference of the shaft 560, and seals the gap between the shaft 560 and the cylinder 570 so that fluid F on one side of the groove 561 in the direction along the central axis P of the groove 561 does not leak to the other side. In the seal ring 500 assembled to the shaft 560 and the cylinder 570, the outer peripheral end surface 525 of the inner ring 520 protrudes slightly from the groove 561 of the shaft 560 toward the cylinder 570.

[0117] 29 , in the seal ring 500 assembled to the shaft 560 and the cylinder 570, the outer peripheral end surface 525 of the inner ring 520 abuts against the cylinder 570, and the side end surface 526 of the inner ring 520 abuts against the side wall surface of the groove portion 561 of the shaft 560. In addition, in the seal ring 500 assembled to the shaft 560 and the cylinder 570, the outer ring 510 is located in a space surrounded by the opposing surfaces 523 and 524 of the inner ring 520, the shaft 560, and the cylinder 570. The outer ring 510 may be spaced apart from at least one of the opposing surfaces 523 and 524 of the inner ring 520, the shaft 560, and the cylinder 570.

[0118] The seal ring 500 effectively achieves the same effects as those achieved when sealing the gap between the movable scroll 540 and the housing 550, even when used to seal the gap between the shaft 560 and the cylinder 570.

[0119] [Sixth embodiment] A seal ring 600 according to a sixth embodiment of the present invention is configured to seal a fluid F on the outer periphery side. FIG. 30 is a plan view of the seal ring 600. FIG. 31 is a cross-sectional view of the seal ring 600 taken along line F-F' in FIG. 30. The seal ring 600 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 30 is an axial cross section of the seal ring 600 taken along a plane including the central axis P. The seal ring 600 has an outer circumferential surface 601, an inner circumferential surface 602, a first side surface 603, and a second side surface 604.

[0120] The seal ring 600 has an inner ring 610 and an outer ring 620. The inner ring 610 and the outer ring 620 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0121] The inner ring 610 has a rectangular axial cross section and includes an inner ring inner circumferential surface 611, an inner ring outer circumferential surface 612, a first inner ring side surface 613, and a second inner ring side surface 614. The inner ring inner circumferential surface 611 is an inward-facing cylindrical surface extending in the axial direction. The inner ring outer circumferential surface 612 is an outward-facing cylindrical surface extending in the axial direction. The first inner ring side surface 613 and the second inner ring side surface 614 are both planes perpendicular to an axis parallel to the central axis P and face opposite each other. The inner ring inner circumferential surface 611 and the first inner ring side surface 613 of the inner ring 610 respectively constitute the inner circumferential surface 602 and the second side surface 604 of the seal ring 600.

[0122] The outer ring 620 has an L-shaped axial cross section and includes an outer ring outer peripheral surface 621 and an outer ring side surface 622. The outer ring outer peripheral surface 621 is an outward-facing cylindrical surface extending in the axial direction. The outer ring side surface 622 is a plane perpendicular to an axis parallel to the central axis P. The outer ring outer peripheral surface 621 and the outer ring side surface 622 of the outer ring 620 respectively constitute the outer peripheral surface 601 and the first side surface 603 of the seal ring 600. The outer ring 620 also has a first opposing surface 623 facing inward, away from the outer ring outer peripheral surface 621. The outer ring 620 also has a second opposing surface 624 perpendicular to an axis parallel to the central axis P and facing away from the outer ring side surface 622. In the seal ring 600, the first opposing surface 623 of the outer ring 620 faces the inner ring outer peripheral surface 612 of the inner ring 610 in a radial direction perpendicular to the central axis P, and the second opposing surface 624 of the outer ring 620 faces the second inner ring side surface 614 of the inner ring 610 in the axial direction.

[0123] The outer ring 620 further has an inner peripheral end surface 625 and a side end surface 626. The inner peripheral end surface 625 is an inward-facing cylindrical surface extending in the axial direction, connecting the outer ring side surface 622 and the second opposing surface 624, and constituting the inner peripheral end of the outer ring 620. The side end surface 626 is a plane that connects the outer ring outer peripheral surface 621 and the first opposing surface 623, and constitutes the axial end of the outer ring 620 opposite the outer ring side surface 622, and is perpendicular to an axis parallel to the central axis P. The inner peripheral end surface 625 of the outer ring 620, together with the inner ring inner peripheral surface 611 of the inner ring 610, constitutes the inner peripheral surface 602 of the seal ring 600. The side end surface 626 of the outer ring 620, together with the first inner ring side surface 613 of the inner ring 610, constitutes the second side surface 604 of the seal ring 600.

[0124] In the seal ring 600, the axial dimension of the first opposing surface 623 of the outer ring 620 is larger than the axial dimension of the inner ring outer peripheral surface 612 of the inner ring 610. Therefore, the side end surface 626 of the outer ring 620 is located axially outward of the first inner ring side surface 613 of the inner ring 610. Therefore, in the seal ring 600, the outer ring 620 protrudes from the first inner ring side surface 613 of the inner ring 610. Furthermore, in the seal ring 600, the radial dimension of the second opposing surface 624 of the outer ring 620 is larger than the radial dimension of the second inner ring side surface 614 of the inner ring 610. Therefore, the inner peripheral end surface 625 of the outer ring 620 is located more inward than the inner ring inner peripheral surface 611. Therefore, in the seal ring 600, the outer ring 620 protrudes from the inner ring inner peripheral surface 611 of the inner ring 610.

[0125] The inner ring 610 is formed of a resin harder than the outer ring 620. Specifically, the inner ring 610 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The outer ring 620 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0126] The axial and radial thicknesses of the inner ring 610 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the outer ring 620 can be, for example, 1.2 mm or more and 5.5 mm or less, respectively.

[0127] 32 shows a state in which the seal ring 600 is assembled to the movable scroll 640 and housing 650 of the scroll compressor. The seal ring 600 assembled to the movable scroll 640 and housing 650 is received in a groove 641 provided in the movable scroll 640, and seals the fluid F on the outer periphery side of the groove 641 in the gap between the movable scroll 640 and the housing 650 so as not to leak to the inner periphery side of the groove 641. In the seal ring 600 assembled to the movable scroll 640 and housing 650, the side end surface 626 of the outer ring 620 protrudes slightly from the groove 641 of the movable scroll 640 toward the housing 650.

[0128] 32 , in the seal ring 600 assembled to the movable scroll 640 and the housing 650, the inner peripheral end surface 625 of the outer ring 620 abuts against the side wall surface of the groove portion 641 of the movable scroll 640, and the side end surface 626 of the outer ring 620 abuts against the housing 650. In addition, in the seal ring 600 assembled to the movable scroll 640 and the housing 650, the inner ring 610 is located in a space surrounded by the opposing surfaces 623, 624 of the outer ring 620, the movable scroll 640, and the housing 650. The inner ring 610 may be spaced apart from at least one of the opposing surfaces 623, 624 of the outer ring 620, the movable scroll 640, and the housing 650.

[0129] 30 to 32, the inner ring 610 is provided with a joint 630. The joint 630 has a first engagement portion 631 and a second engagement portion 632 that are mutually movable. As a result, the inner ring 610 can be assembled into the groove 641 of the movable scroll 640 in an expanded diameter state as a whole by expanding the first engagement portion 631 and the second engagement portion 632 circumferentially at the joint 630. The joint 630 of the inner ring 610 is configured similarly to the joint 230 of the inner ring 210 of the seal ring 200 according to the second embodiment shown in FIGS. 7 to 10.

[0130] In seal ring 600, inner ring 610 formed from the hard first resin provides high durability that can prevent damage caused by stress from the high-pressure fluid F that is to be sealed. In addition, in seal ring 600, inner ring 610 adjacent to the gap between movable scroll 640 and housing 650 is formed from the hard first resin, thereby preventing creep deformation of inner ring 610 from entering the gap between movable scroll 640 and housing 650.

[0131] Furthermore, in the seal ring 600, by using the outer ring 620 formed from the soft second resin, the inner peripheral end surface 625 and the side end surface 626 of the outer ring 620 are in close contact with the movable scroll 640 and the housing 650. Therefore, in the seal ring 600, the fluid F is prevented from entering the region between the inner peripheral end surface 625 of the outer ring 620 and the movable scroll 640, and the region between the side end surface 626 of the outer ring 620 and the housing 650. As a result, the seal ring 600 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F, particularly from the butt portion 630 of the inner ring 610.

[0132] The configuration of the seal ring 600 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 640 and the housing 650. For example, in the seal ring 600, the configuration of the butt joint 630 of the inner ring 610 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 600, butt joints may be provided not only in the inner ring 610 but also in the outer ring 620. The structure of the butt joint 630 of the inner ring 610 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the outer ring 620 can be, for example, double angled, straight, angled, or the like.

[0133] [Seventh embodiment] A seal ring 700 according to a seventh embodiment of the present invention is configured to seal a fluid F on the inner circumferential side. FIG. 33 is a plan view of the seal ring 700. FIG. 34 is a cross-sectional view of the seal ring 700 taken along line G-G' in FIG. 33. The seal ring 700 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 34 is an axial cross section of the seal ring 700 taken along a plane including the central axis P. The seal ring 700 has an outer circumferential surface 701, an inner circumferential surface 702, a first side surface 703, and a second side surface 704.

[0134] The seal ring 700 has an outer ring 710 and an inner ring 720. The outer ring 710 and the inner ring 720 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0135] The outer ring 710 has an outer ring outer peripheral surface 711, an outer ring side surface 712, and an inner tapered surface 713. The outer ring outer peripheral surface 711 of the outer ring 710 is an outward-facing cylindrical surface extending in the axial direction. The outer ring side surface 712 of the outer ring 710 is a plane extending inward from the end of the outer ring outer peripheral surface 711 and perpendicular to an axis parallel to the central axis P. The inner tapered surface 713 of the outer ring 710 is an inclined surface facing inward, inclined with respect to the outer ring outer peripheral surface 711 and the outer ring side surface 712, and formed with a gap between them. The outer ring outer peripheral surface 711 and the outer ring side surface 712 of the outer ring 710 respectively constitute the outer peripheral surface 701 and the first side surface 703 of the seal ring 700.

[0136] The inner ring 720 has an inner ring inner circumferential surface 721, an inner ring side surface 722, and an outer tapered surface 723. The inner ring inner circumferential surface 721 of the inner ring 720 is an outward-facing cylindrical surface extending in the axial direction. The inner ring side surface 722 of the inner ring 720 is a plane extending inward from the end of the inner ring inner circumferential surface 721 and perpendicular to an axis parallel to the central axis P. The outer tapered surface 723 of the inner ring 720 is an inclined surface facing outward, inclined with respect to the inner ring inner circumferential surface 721 and the inner ring side surface 722, and formed with a gap between them. The inner ring inner circumferential surface 721 and the inner ring side surface 722 of the inner ring 720 respectively constitute the inner circumferential surface 702 and the second side surface 704 of the seal ring 700.

[0137] In seal ring 700, an inner tapered surface 713 of outer ring 710 and an outer tapered surface 723 of inner ring 720 face each other. Furthermore, in seal ring 700, an angle α formed between outer ring outer peripheral surface 711 and inner tapered surface 713 of outer ring 710 is equal to an angle β formed between inner ring inner peripheral surface 721 and outer tapered surface 723 of inner ring 720. Therefore, in seal ring 700, outer ring outer peripheral surface 711 of outer ring 710 and inner ring inner peripheral surface 721 of inner ring 720 face each other in the radial direction perpendicular to central axis P, and an outer ring side surface 712 of outer ring 710 and inner ring side surface 722 of inner ring 720 face each other in the axial direction.

[0138] The inner ring 720 further has an outer peripheral end surface 725 and a side end surface 726. The outer peripheral end surface 725 is an outwardly facing cylindrical surface extending in the axial direction, connecting the inner ring side surface 722 and the outer tapered surface 723, and constituting the outer peripheral end of the inner ring 720. The side end surface 726 is a plane that connects the inner ring inner peripheral surface 721 and the outer tapered surface 723, and constitutes the axial end of the inner ring 720 opposite the inner ring side surface 722, and is perpendicular to an axis parallel to the central axis P. The outer peripheral end surface 725 of the inner ring 720, together with the outer ring outer peripheral surface 711 of the outer ring 710, constitutes the outer peripheral surface 701 of the seal ring 700. The side end surface 726 of the inner ring 720, together with the outer ring side surface 712 of the outer ring 710, constitutes the first side surface 703 of the seal ring 700.

[0139] In the seal ring 700, the side end surface 726 of the inner ring 720 is located axially outward from the outer ring side surface 712 of the outer ring 710. Therefore, in the seal ring 700, the inner ring 720 protrudes from the outer ring side surface 712 of the outer ring 710. Also, in the seal ring 700, the outer peripheral end surface 725 of the inner ring 720 is located outer than the outer ring outer peripheral surface 711 of the outer ring 710. Therefore, in the seal ring 700, the inner ring 720 protrudes from the outer ring outer peripheral surface 711 of the outer ring 710.

[0140] The outer ring 710 is formed of a harder resin than the inner ring 720. Specifically, the outer ring 710 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The inner ring 720 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0141] The maximum axial and radial thicknesses of the outer ring 710 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the inner ring 720 can be, for example, 1.2 mm or more and 5.5 mm or less, respectively.

[0142] 35 shows a state in which the seal ring 700 is assembled to the movable scroll 740 and housing 750 of a scroll compressor. The seal ring 700 assembled to the movable scroll 740 and housing 750 is received in a groove 741 provided in the movable scroll 740, and seals the fluid F on the inner circumferential side of the groove 741 in the gap between the movable scroll 740 and the housing 750 so as not to leak to the outer circumferential side of the groove 741. In the seal ring 700 assembled to the movable scroll 740 and housing 750, the side end surface 726 of the inner ring 720 protrudes slightly from the groove 741 of the movable scroll 740 toward the housing 750.

[0143] 35 , in the seal ring 700 assembled to the movable scroll 740 and the housing 750, the outer peripheral end surface 725 of the inner ring 720 abuts against the side wall surface of the groove portion 741 of the movable scroll 740, and the side end surface 726 of the inner ring 720 abuts against the housing 750. In addition, in the seal ring 700 assembled to the movable scroll 740 and the housing 750, the outer ring 710 is positioned within a space surrounded by the outer tapered surface 723 of the inner ring 720, the movable scroll 740, and the housing 750. The outer ring 710 may be spaced apart from at least one of the outer tapered surface 723 of the inner ring 720, the movable scroll 740, and the housing 750.

[0144] 33 to 35, the outer ring 710 is provided with a joint portion 730. The joint portion 730 has a first engagement portion 731 and a second engagement portion 732 that are mutually movable. As a result, the outer ring 710 can be assembled into the groove portion 741 of the movable scroll 740 in an expanded diameter state as a whole by expanding the first engagement portion 731 and the second engagement portion 732 circumferentially at the joint portion 730. The joint portion 730 of the outer ring 710 is configured similarly to the joint portion 330 of the outer ring 310 of the seal ring 300 according to the third embodiment shown in FIGS. 11 to 14.

[0145] In the seal ring 700, the outer ring 710 formed from the hard first resin provides high durability that can prevent damage caused by stress from the high-pressure fluid F that is the object of sealing. In addition, in the seal ring 700, the outer ring 710 adjacent to the gap between the movable scroll 740 and the housing 750 is formed from the hard first resin, thereby preventing creep deformation of the outer ring 710 from entering the gap between the movable scroll 740 and the housing 750.

[0146] Furthermore, in the seal ring 700, by using the inner ring 720 formed from the soft second resin, the adhesion of the outer peripheral end surface 725 and the side end surface 726 of the inner ring 720 to the movable scroll 740 and the housing 750 is improved. Therefore, in the seal ring 700, the fluid F is prevented from entering the region between the outer peripheral end surface 725 of the inner ring 720 and the movable scroll 740, and the region between the side end surface 726 of the inner ring 720 and the housing 750. As a result, the seal ring 700 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F, particularly from the butt portion 730 of the outer ring 710.

[0147] The configuration of the seal ring 700 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 740 and the housing 750. For example, in the seal ring 700, the configuration of the butt joint 730 of the outer ring 710 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 700, butt joints may be provided not only in the outer ring 710 but also in the inner ring 720. The structure of the butt joint 730 of the outer ring 710 can be, for example, straight, step cut, angled, triple step, or the like, in addition to double angle. In addition, the structure of the butt joint of the inner ring 720 can be, for example, double angled, straight, angled, or the like.

[0148] The seal ring 700 can also be used to seal the gap between a shaft and a cylinder that reciprocate relative to one another. Figure 36 shows the seal ring 700 assembled to a shaft 760 and a cylinder 770. The seal ring 700 assembled to the shaft 760 and the cylinder 770 is received in a groove 761 provided around the entire circumference of the shaft 760, and seals the gap between the shaft 760 and the cylinder 770 so that fluid F on one side of the groove 761 in the direction along the central axis P of the groove 761 does not leak to the other side. In the seal ring 700 assembled to the shaft 760 and the cylinder 770, the outer peripheral end surface 725 of the inner ring 720 protrudes slightly from the groove 761 of the shaft 760 toward the cylinder 770.

[0149] 36 , in the seal ring 700 assembled to the shaft 760 and the cylinder 770, the outer peripheral end surface 725 of the inner ring 720 abuts against the cylinder 770, and the side end surface 726 of the inner ring 720 abuts against the side wall surface of the groove portion 761 of the shaft 760. In addition, in the seal ring 700 assembled to the shaft 760 and the cylinder 770, the outer ring 710 is positioned in a space surrounded by the outer tapered surface 723 of the inner ring 720, the shaft 760, and the cylinder 770. The outer ring 710 may be spaced apart from at least one of the outer tapered surface 723 of the inner ring 720, the shaft 760, and the cylinder 770.

[0150] The seal ring 700 effectively achieves the same effects as those achieved when sealing the gap between the movable scroll 740 and the housing 750, even when used to seal the gap between the shaft 760 and the cylinder 770.

[0151] [Eighth embodiment] A seal ring 800 according to an eighth embodiment of the present invention is configured to seal a fluid F on the outer periphery side. FIG. 37 is a plan view of the seal ring 800. FIG. 38 is a cross-sectional view of the seal ring 800 taken along line H-H' in FIG. 37. The seal ring 800 is configured in an annular shape centered on a central axis P. The cross section shown in FIG. 38 is an axial cross section of the seal ring 800 taken along a plane including the central axis P. The seal ring 800 has an outer circumferential surface 801, an inner circumferential surface 802, a first side surface 803, and a second side surface 804.

[0152] The seal ring 800 has an inner ring 810 and an outer ring 820. The inner ring 810 and the outer ring 820 share a common central axis P and are stacked on top of each other in the axial direction along the central axis P.

[0153] The inner ring 810 has an inner ring inner circumferential surface 811, an inner ring side surface 812, and an outer tapered surface 813. The inner ring inner circumferential surface 811 of the inner ring 810 is an inward-facing cylindrical surface extending in the axial direction. The inner ring side surface 812 of the inner ring 810 is a plane extending inward from the end of the inner ring inner circumferential surface 811 and perpendicular to an axis parallel to the central axis P. The outer tapered surface 813 of the inner ring 810 is an inclined surface facing outward, inclined with respect to the inner ring inner circumferential surface 811 and the inner ring side surface 812, and formed with a gap between them. The inner ring inner circumferential surface 811 and the inner ring side surface 812 of the inner ring 810 respectively constitute the inner circumferential surface 802 and the second side surface 804 of the seal ring 800.

[0154] The outer ring 820 has an outer ring outer peripheral surface 821, an outer ring side surface 822, and an inner tapered surface 823. The outer ring outer peripheral surface 821 of the outer ring 820 is an inward-facing cylindrical surface extending in the axial direction. The outer ring side surface 822 of the outer ring 820 is a plane extending from the end of the outer ring outer peripheral surface 821 toward the inner peripheral side and perpendicular to an axis parallel to the central axis P. The inner tapered surface 823 of the outer ring 820 is an inclined surface facing the inner peripheral side that is inclined with respect to the outer ring outer peripheral surface 821 and the outer ring side surface 822 and is formed with a gap between the outer ring outer peripheral surface 821 and the outer ring side surface 822. The outer ring outer peripheral surface 821 and the outer ring side surface 822 of the outer ring 820 respectively constitute the outer peripheral surface 801 and the first side surface 803 of the seal ring 800.

[0155] In seal ring 800, an outer tapered surface 813 of inner ring 810 and an inner tapered surface 823 of outer ring 820 face each other. Furthermore, in seal ring 800, an angle α formed between an inner ring inner circumferential surface 811 and the outer tapered surface 813 of inner ring 810 is equal to an angle β formed between an outer ring outer circumferential surface 821 and the inner tapered surface 823 of outer ring 820. Therefore, in seal ring 800, an inner ring inner circumferential surface 811 of inner ring 810 and an outer ring outer circumferential surface 821 of outer ring 820 face each other in the radial direction perpendicular to central axis P, and an inner ring side surface 812 of inner ring 810 and an outer ring side surface 822 of outer ring 820 face each other in the axial direction.

[0156] The outer ring 820 further has an inner peripheral end surface 825 and a side end surface 826. The inner peripheral end surface 825 is an inward-facing cylindrical surface extending in the axial direction that connects the outer ring side surface 822 and the inner tapered surface 823 and constitutes the inner peripheral end of the outer ring 820. The side end surface 826 is a plane that connects the outer ring outer peripheral surface 821 and the inner tapered surface 823 and constitutes the axial end of the outer ring 820 opposite the outer ring side surface 822, and is perpendicular to an axis parallel to the central axis P. The inner peripheral end surface 825 of the outer ring 820, together with the inner ring inner peripheral surface 811 of the inner ring 810, constitutes the inner peripheral surface 802 of the seal ring 800. The side end surface 826 of the outer ring 820, together with the inner ring side surface 812 of the inner ring 810, constitutes the second side surface 804 of the seal ring 800.

[0157] In the seal ring 800, a side end face 826 of the outer ring 820 is located axially outward from an inner ring side surface 812 of the inner ring 810. Therefore, in the seal ring 800, the outer ring 820 protrudes from the inner ring side surface 812 of the inner ring 810. Also, in the seal ring 800, an inner peripheral end face 825 of the outer ring 820 is located more inward than an inner ring inner peripheral surface 811 of the inner ring 810. Therefore, in the seal ring 800, the outer ring 820 protrudes from the inner ring inner peripheral surface 811 of the inner ring 810.

[0158] The inner ring 810 is formed of a resin harder than the outer ring 820. Specifically, the inner ring 810 is formed of a first resin having a flexural modulus of 700 MPa or more. The flexural modulus of the first resin is preferably 1000 MPa or more, and more preferably 1500 MPa or more. Examples of the first resin that can be used include polyether ether ketone (PEEK), polyphenylene sulfide (PPS), nylon 66, polyphenol (PF), polyethylene terephthalate (PBT), polyimide (PI), polyamide-imide (PAI), polyacetal (POM), and polyphthalamide (PPA). The outer ring 820 is formed of a second resin having a flexural modulus of less than 700 MPa. Examples of the second resin that can be used include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), fluororubber (FKM), and hydrogenated nitrile rubber (HNBR).

[0159] The maximum axial and radial thicknesses of the inner ring 810 can be, for example, 1.0 mm or more and 5.0 mm or less, respectively. The maximum axial and radial thicknesses of the outer ring 820 can be, for example, 1.2 mm or more and 5.5 mm or less, respectively.

[0160] 39 shows a state in which the seal ring 800 is assembled to the movable scroll 840 and housing 850 of a scroll compressor. The seal ring 800 assembled to the movable scroll 840 and housing 850 is received in a groove 841 provided in the movable scroll 840, and seals the fluid F on the outer periphery side of the groove 841 in the gap between the movable scroll 840 and the housing 850 so as not to leak to the inner periphery side of the groove 841. In the seal ring 800 assembled to the movable scroll 840 and housing 850, the side end surface 826 of the outer ring 820 protrudes slightly from the groove 841 of the movable scroll 840 toward the housing 850.

[0161] 39 , in the seal ring 800 assembled to the movable scroll 840 and the housing 850, the inner peripheral end surface 825 of the outer ring 820 abuts against the side wall surface of the groove portion 841 of the movable scroll 840, and the side end surface 826 of the outer ring 820 abuts against the housing 850. In addition, in the seal ring 800 assembled to the movable scroll 840 and the housing 850, the inner ring 810 is located in a space surrounded by the inner tapered surface 823 of the outer ring 820, the movable scroll 840, and the housing 850. The inner ring 810 may be spaced apart from at least one of the inner tapered surface 823 of the outer ring 820, the movable scroll 840, and the housing 850.

[0162] 37 to 39, the inner ring 810 is provided with a joint 830. The joint 830 has a first engagement portion 831 and a second engagement portion 832 that are mutually movable. As a result, the inner ring 810 can be assembled into the groove 841 of the movable scroll 840 in an expanded diameter state as a whole by expanding the first engagement portion 831 and the second engagement portion 832 circumferentially at the joint 830. The joint 830 of the inner ring 810 is configured similarly to the joint 430 of the inner ring 410 of the seal ring 400 according to the fourth embodiment shown in FIGS. 20 to 23.

[0163] In seal ring 800, inner ring 810 formed from the hard first resin provides high durability that can prevent damage caused by stress from the high-pressure fluid F that is the object of sealing. Also, in seal ring 800, inner ring 810 adjacent to the gap between movable scroll 840 and housing 850 is formed from the hard first resin, thereby preventing creep deformation of inner ring 810 from entering the gap between movable scroll 840 and housing 850.

[0164] Furthermore, in the seal ring 800, by using the outer ring 820 formed from the soft second resin, the inner circumferential end surface 825 and the side end surface 826 of the outer ring 820 are in close contact with the movable scroll 840 and the housing 850. As a result, in the seal ring 800, the fluid F is prevented from entering the region between the inner circumferential end surface 825 of the outer ring 820 and the movable scroll 840, and the region between the side end surface 826 of the outer ring 820 and the housing 850. As a result, the seal ring 800 has high leakage prevention performance for the fluid F, and can effectively prevent leakage of the fluid F, particularly from the butt portion 830 of the inner ring 810.

[0165] The configuration of the seal ring 800 is not limited to the above and can be modified in various ways depending on the specifications of the movable scroll 840 and the housing 850. For example, in the seal ring 800, the configuration of the butt joint 830 of the inner ring 810 can be modified in various ways depending on the allowable leakage amount of the fluid F. In addition, in the seal ring 800, butt joints may be provided not only in the inner ring 810 but also in the outer ring 820. The structure of the butt joint 830 of the inner ring 810 can be, for example, straight, step cut, angled, or triple step, in addition to double angle. In addition, the structure of the butt joint of the outer ring 820 can be, for example, double angled, straight, or angled.

[0166] [Example] (Sample preparation) In Example 1, a sample of the seal ring 100 (see FIG. 3, etc.) according to the first embodiment was produced. In the sample according to Example 1, the outer ring 110 was made of PEEK, and the inner ring 120 was made of PTFE. In the sample according to Example 1, the outer diameter of the outer ring 110 was φ80 mm, the axial and radial wall thicknesses of the outer ring 110 were both 5 mm, and the maximum axial and radial wall thicknesses of the inner ring 120 were both 5 mm. The abutment portion 130 of the outer ring 110 had a double angle configuration (see FIG. 4).

[0167] In Example 2, a sample of the seal ring 300 (see FIG. 13, etc.) according to the third embodiment was produced. In the sample according to Example 2, the outer ring 310 was made of PEEK, and the inner ring 320 was made of PTFE. In the sample according to Example 2, the outer diameter of the outer ring 310 was φ80 mm, the maximum axial and radial thicknesses of the outer ring 310 were both 5 mm, and the maximum axial and radial thicknesses of the inner ring 320 were both 5 mm. The abutment portion 130 of the outer ring 310 had a double-angle configuration (see FIG. 14).

[0168] In Example 3, a sample of the seal ring 500 (see FIG. 28, etc.) according to the fifth embodiment was produced. In the sample according to Example 3, the outer ring 510 was made of PEEK, and the inner ring 520 was made of PTFE. In the sample according to Example 3, the outer diameter of the inner ring 520 was φ80 mm, the axial and radial dimensions of the outer ring 510 were both 5 mm, and the maximum axial and radial dimensions of the inner ring 520 were both 5 mm. The abutment portion 130 of the outer ring 510 had a double-angle configuration (see FIG. 4).

[0169] In Example 4, a sample of the seal ring 700 (see FIG. 35, etc.) according to the seventh embodiment was produced. In the sample according to Example 4, the outer ring 710 was made of PEEK, and the inner ring 720 was made of PTFE. In the sample according to Example 4, the outer diameter of the inner ring 720 was φ80 mm, the maximum axial and radial thicknesses of the outer ring 710 were both 5 mm, and the maximum axial and radial thicknesses of the inner ring 720 were both 5 mm. The abutment portion 130 of the outer ring 710 had a double angle configuration (see FIG. 14).

[0170] (Evaluation of durability performance) A seal ring sample according to Comparative Example 1 was prepared as a benchmark for durability performance. The sample according to Comparative Example 1 was configured as a single seal ring made of PTFE and having a rectangular cross section. The sample according to Comparative Example 1 had an outer diameter of φ80 mm and wall thicknesses in both the axial and radial directions of 5 mm. The abutment portion of the sample according to Comparative Example 1 had a double angle configuration (see FIG. 4).

[0171] Durability was evaluated for the samples according to Examples 1 to 4. To evaluate durability, each sample was assembled to a movable scroll and a housing, and a durability test was conducted by applying hydraulic pressure from the inner peripheral side. The durability test was a static pressure test in which the movable scroll was not moved. In the durability test, the oil temperature was set to 150°C, and a cycle of holding the hydraulic pressure at 3 MPa for 3 seconds and then at 11 MPa for 6 seconds was repeated. The durability of the samples according to Examples 1 to 4 was evaluated based on the time (durability time) until damage (such as breakage or buckling) occurred to each sample in the durability test.

[0172] Fig. 40 is a graph showing the evaluation results of the durability performance of the samples according to Examples 1 to 4 and the sample according to Comparative Example 1. In Fig. 40, the vertical axis represents the durability time (hours). It can be seen that the samples according to Examples 1 to 4 have durability performance that is orders of magnitude higher than that of the sample according to Comparative Example 1. It can also be seen that particularly high durability is achieved in Examples 1 and 2, in which the hard outer ring comes into contact with the movable scroll and the housing.

[0173] (Evaluation of leak prevention performance) A seal ring sample according to Comparative Example 2 was prepared as a benchmark for leak prevention performance. The sample according to Comparative Example 2 was configured as a single seal ring made of PEEK and having a rectangular cross section. The sample according to Comparative Example 1 had an outer diameter of φ80 mm and wall thicknesses in both the axial and radial directions of 3 mm. The abutment section of the sample according to Comparative Example 2 had a triple-step configuration (see FIG. 5(D)).

[0174] The samples according to Examples 1 to 4 were evaluated for leak prevention performance. To evaluate the leak prevention performance, each sample was assembled to a movable scroll and a housing, and a sealing test was performed by applying hydraulic pressure from the inner peripheral side. The sealing test was a static pressure test in which the movable scroll was not moved. In the sealing test, the oil temperature was 150°C and the hydraulic pressure was 11 MPa. The leak prevention performance of the samples according to Examples 1 to 4 was evaluated based on the ratio of the reduction in leakage volume per minute (ml / sec) in the sealing test (leakage volume reduction rate) compared to the sample according to Comparative Example 2.

[0175] Fig. 41 is a graph showing the evaluation results of the leakage prevention performance of the samples according to Examples 1 to 4. In Fig. 41, the vertical axis represents the leakage reduction rate (%). It can be seen that the samples according to Examples 1 to 4 had significantly reduced leakage compared to the sample according to Comparative Example 2. It can also be seen that the samples according to Examples 1 and 2, in which the hard outer ring comes into contact with the movable scroll and the housing, had an even greater reduction in leakage compared to the sample according to Comparative Example 2. [Explanation of symbols]

[0176] 100, 200, 300, 400, 500, 600, 700, 800... Seal ring 101,201,301,401,501,601,701,801…Outer surface 102,202,302,402,502,602,702,802…Inner peripheral surface 103,203,303,403,503,603,703,803…First side 104,204,304,404,504,604,704,804…Second side 110, 220, 310, 420, 510, 620, 710, 820...Outer ring 120, 210, 320, 410, 520, 610, 720, 810...Inner ring 111, 221, 311, 421, 511, 621, 711, 821...Outer ring outer surface 112,512...Inner surface of outer ring 113,513...First outer ring side 114,514...Side of the second outer ring 121, 211, 321, 411, 521, 611, 721, 811...Inner ring inner surface 122, 322, 412, 522, 722, 812...Inner ring side 123, 223, 523, 623...First opposing surface 124, 224, 524, 624...Second opposing surface 130,230,330,430,530,630,730,830…Join part 212,612...Outer surface of inner ring 213,613...First inner ring side 214,614...Side of the second inner ring 222, 312, 422, 622, 712, 822...Outer ring side 313, 423, 713, 823...Inner tapered surface 323, 413, 723, 813...Outer tapered surface F…Fluid

Claims

1. A seal ring having an outer peripheral surface, an inner peripheral surface, a first side surface, and a second side surface, an outer ring having an outer ring outer peripheral surface that constitutes the outer peripheral surface and a first outer ring side surface that constitutes the first side surface; an inner ring having an inner ring inner peripheral surface that constitutes the inner peripheral surface and a first inner ring side surface that constitutes the second side surface; Equipped with the outer ring is formed of a first resin having a flexural modulus of 700 MPa or more, and the inner ring is formed of a second resin having a flexural modulus of less than 700 MPa; the outer ring has a joint, The seal ring seals the fluid on the inner periphery side. Seal ring.

2. 2. The seal ring according to claim 1, the outer ring further has an outer ring inner peripheral surface facing away from the outer ring outer peripheral surface and a second outer ring side surface facing away from the first outer ring side surface, The inner ring further has a first opposing surface opposing the inner peripheral surface of the outer ring and a second opposing surface opposing the second outer ring side surface. Seal ring.

3. 2. The seal ring according to claim 1, The outer ring further has an inner tapered surface inclined relative to the outer peripheral surface of the outer ring, The inner ring further has an outer tapered surface that is inclined relative to the inner ring inner peripheral surface and faces the inner tapered surface. Seal ring.

4. The seal ring according to any one of claims 1 to 3, The inner ring does not protrude from the outer peripheral surface of the outer ring and the first outer ring side surface. Seal ring.

5. The seal ring according to any one of claims 1 to 3, The inner ring protrudes from the outer peripheral surface of the outer ring and the first outer ring side surface. Seal ring.

6. The seal ring according to any one of claims 1 to 3, The abutment portion includes a first engaging portion having an outer inclined surface connecting the outer ring outer peripheral surface and the first outer ring side surface, and a second engaging portion having an inner inclined surface facing the outer inclined surface. Seal ring.

7. A seal ring having an outer peripheral surface, an inner peripheral surface, a first side surface, and a second side surface, an outer ring having an outer ring outer peripheral surface that constitutes the outer peripheral surface and a first outer ring side surface that constitutes the first side surface; an inner ring having an inner ring inner peripheral surface that constitutes the inner peripheral surface and a first inner ring side surface that constitutes the second side surface; Equipped with the inner ring is formed of a first resin having a flexural modulus of elasticity of 700 MPa or more, and the outer ring is formed of a second resin having a flexural modulus of elasticity of less than 700 MPa, the inner ring has a joint, The seal ring seals the fluid on the outer periphery. Seal ring.

8. 8. The seal ring according to claim 7, the inner ring further has an inner ring outer peripheral surface facing away from the inner ring inner peripheral surface and a second inner ring side surface facing away from the first inner ring side surface, The outer ring further has a first opposing surface opposing the outer peripheral surface of the inner ring and a second opposing surface opposing the second inner ring side surface. Seal ring.

9. 8. The seal ring according to claim 7, the inner ring further has an outer tapered surface inclined relative to the inner ring inner peripheral surface, The outer ring further has an inner tapered surface that is inclined relative to the outer peripheral surface of the outer ring and faces the outer tapered surface. Seal ring.

10. The seal ring according to any one of claims 7 to 9, The outer ring does not protrude from the inner peripheral surface of the inner ring and the first inner ring side surface. Seal ring.

11. The seal ring according to any one of claims 7 to 9, The outer ring protrudes from the inner peripheral surface of the inner ring and the first inner ring side surface. Seal ring.

12. The seal ring according to any one of claims 7 to 9, The abutment portion includes a first engaging portion having an inner inclined surface connecting the inner ring inner circumferential surface and the first inner ring side surface, and a second engaging portion having an outer inclined surface facing the inner inclined surface. Seal ring.

Images