JP2016121762A - Shaft seal device and compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain sealability of a seal surface over a long period.SOLUTION: On a seal surface of housings 53, 55, 57 and a stationary ring 21 and a seal surface of a shaft 63 and a rotary ring 22, provided is an annular and resin-based U ring 23 in which projection parts 23a 23b are formed on the outside of an opening and of which a cross section is formed into s U shape. The U ring 23 is arranged so that the opening faces toward the refrigerant side of the insides of the housings 53, 57. The projection parts 23a, 23b formed on the outside of the opening are pushed against the seal surface by elasticity. The U ring 23 uses a resin satisfying four requirements: heat resistance; foam resistance; permeation resistance of carbon dioxide; ultralow temperature resistance.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a shaft seal device and a compressor for a compressor that compresses a carbon dioxide refrigerant.

  A general compressor has a compression mechanism that generates fluid pressure in a fluid in a housing by rotation of a shaft. Such a compressor includes a shaft seal device that prevents fluid from leaking out of the housing through a gap between the housing and the shaft.

In recent years, in such a compressor, carbon dioxide (CO ₂ ), which is replaced with chlorofluorocarbon, is being adopted as a refrigerant gas. When such a refrigerant gas is used, the pressure acting on the shaft seal device may be 10 times or more than when using chlorofluorocarbon, the load on the shaft seal device is large, and the durability of the shaft seal device is high. A decrease is more likely to occur.

  Therefore, in order to improve the durability, it is fixed to the shaft hole, and is fixed to the shaft that is fixed to the shaft located in the housing and the fixed ring having the fixed side seal end surface on the working part side of the fixed ring. A rotary ring in which a rotary side seal end face that is in sliding contact with the fixed side seal end face is formed on the passive part side of the rotary ring, and a packing (O-ring) that is fixed to the shaft and seals the gap between the shaft and the rotary ring. There is a shaft seal device provided with a spring that is fixed to the shaft and presses the rotating ring in the axial direction outside the housing (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2007-9886

  In the shaft seal device of the compressor as described in Patent Document 1, the fixed-side seal end surface and the rotary-side seal end surface slide, and frictional heat is generated at the sliding portion. In addition, when carbon dioxide is employed, the ambient temperature of the shaft seal device is higher than that when chlorofluorocarbon is used. Therefore, such a shaft seal device is required to have excellent heat resistance.

  In such a compressor, the atmospheric pressure of the shaft seal device always fluctuates greatly during operation. In such a compressor, the refrigerant repeatedly enters and exits the packing that seals the gap between the shaft and the rotating ring by the pressure of the carbon dioxide refrigerant during operation. At this time, the refrigerant gas that has penetrated into the packing in a high-pressure environment repeats a process of expanding inside the packing during decompression or the like, and a foaming phenomenon occurs in which a crack or the like occurs in the packing. In order to prevent such a phenomenon from occurring, the shaft seal device of such a compressor is required to have excellent foam resistance.

  In addition, the molecular weight of carbon dioxide is lower than that of Freon. For this reason, in such a compressor, the permeability is very high, and carbon dioxide tends to leak out of the housing through the packing that seals the gap between the shaft and the rotating ring. In order to prevent such a phenomenon from occurring, the shaft seal device of such a compressor is also required to have excellent carbon dioxide permeation resistance.

  Moreover, the compressor mounted in a vehicle air conditioner may be used in an extremely low temperature state. For this reason, such a shaft seal device of a compressor is also required to ensure airtightness even at extremely low temperatures.

  As described above, such a shaft seal device for a compressor is required to have excellent heat resistance, foam resistance, carbon dioxide permeation resistance, and cryogenic resistance.

  However, the compressor described in Patent Document 1 has a configuration in which a contact surface (seal portion) between the shaft and the rotary ring is sealed by packing (O-ring), and such packing is generally rubber. A material is used. However, when packing is made of rubber material, it is difficult to satisfy the four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance and cryogenic temperature resistance. Difficult to maintain.

  The present invention has been made in view of the above problems, and an object thereof is to maintain the sealing performance of the sealing surface for a longer period of time.

  To achieve the above object, the invention according to claim 1 is a shaft seal device (20) of a compressor (51) for compressing a carbon dioxide refrigerant, wherein the housing (53, 55, 57) accommodates the refrigerant. A rotating ring (22) fixed to the shaft (63) located inside the shaft, and a fixing ring (rotatingly supported by the shaft hole (53b) formed in the housing and rotatably supporting the shaft inserted through the shaft hole ( 21), and at least one of the sealing surface of the housing and the stationary ring and the sealing surface of the shaft and the rotary ring has an opening, and protrusions (23a to 25a, 23b) on both outer sides of the opening. ˜25b) is formed, and the sealing member (23-25) made of an annular resin is provided, and the sealing member is arranged so that the opening faces the refrigerant side inside the housing, and both outer sides of the opening. Protrusions formed on It is characterized in that is adapted to be pressed against the seal surface by sex.

  Here, a resin that satisfies the four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance and cryogenic temperature resistance can be used for the seal member. Such a resin seal member can satisfy, for example, four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance, and cryogenic resistance that cannot be satisfied by a rubber material, and further elastic deformation. Since the protrusions formed on both outer sides of the opening can be pressed against the sealing surface, the sealing performance of the sealing surface can be maintained for a longer period of time.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a longitudinal section of the compressor concerning a 1st embodiment of the present invention. It is the Z section enlarged view in FIG. It is sectional drawing of the contact surface of the rotating ring and shaft of the shaft-seal apparatus which concerns on 1st Embodiment. It is the figure which showed the mode of the cross section of the U-ring of the shaft seal device which concerns on 1st Embodiment. It is a figure for demonstrating the action | operation of a U ring. It is the figure which compared the characteristic of the various rubber materials at the time of carbon dioxide refrigerant use. It is the figure which showed the structure of the U-ring of the shaft seal apparatus which concerns on 2nd Embodiment. It is a figure for demonstrating the U ring of the shaft seal apparatus which concerns on 2nd Embodiment. It is the figure which showed the structure of the U-ring of the shaft seal apparatus which concerns on 3rd Embodiment. It is a figure for demonstrating the U ring of the shaft seal apparatus which concerns on 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
Hereinafter, a compressor and a shaft seal device according to a first embodiment of the present invention will be described with reference to FIGS. The compressor according to the present embodiment changes the stroke of the reciprocating piston by changing the inclination angle of the swash plate arranged to be inclined with respect to the center line of the drive shaft, thereby reducing the discharge capacity of the compressor. The swash plate compressor 51 is changed. The swash plate compressor 51 is a compressor that compresses a carbon dioxide refrigerant. The swash plate compressor 51 is applied to an air conditioner such as an automobile.

  The swash plate compressor 51 has a bottomed cylindrical front housing 53. A cylinder block 55 is provided at the opening of the bottomed cylindrical front housing 53 so as to close the opening, and a rear housing 57 is provided at the cylinder block 55. Radial bearings 59 and 61 are provided at the center portion of the bottom wall 53 a of the front housing 53 and the center portion of the cylinder block 55, and a shaft 63 is pivotally supported between the radial bearings 59 and 61. The front housing 53, the cylinder block 55, and the rear housing 57 constitute a housing that stores the refrigerant.

  A shaft seal device 20 called a mechanical seal is provided on the bottom wall 53a of the front housing 53 on the front side (left side in the drawing) from the radial bearing 59. The shaft seal device 20 is for preventing the refrigerant from leaking out of the front housing 53 through the gap between the front housing 53 and the shaft 63. The shaft seal device 20 will be described in detail later.

  On the bottom wall 53a of the front housing 53, a disc-shaped lug plate 73 fixed to the shaft 63 is provided. A thrust bearing 75 is interposed between the lug plate 73 and the bottom wall 53a, and receives an axial load due to a piston compression reaction force.

  A swash plate 77 is provided between the lug plate 73 of the shaft 63 and the cylinder block 55 so as to be rotatable with respect to the axial direction of the shaft 63. The swash plate 77 and the lug plate 73 are coupled so as to be tiltable by a link mechanism 79 provided on the lug plate 73 and a pin 81 provided on the swash plate 77, and the rotation of the lug plate 73 is inclined. This is transmitted to the plate 77.

  Cylinder bores 83 are formed in the cylinder block 55 at regular intervals in the circumferential direction. The cylinder bore 83 is disposed parallel to the axis of the shaft 63, and a piston 85 is inserted therein so as to be able to reciprocate.

  The piston 85 is provided with a spherical bearing 87. The spherical bearing 87 is engaged with a pair of shoes 89 holding the outer peripheral portion of the swash plate 77 so as to be slidable in the circumferential direction.

  A valve plate 91 is interposed between the cylinder block 55 and the rear housing 57, and a suction valve 93 is provided between the valve plate 91 and the cylinder block 55 to seal the suction port. It is like that.

  A suction chamber 95 and a discharge chamber 97 are provided inside the rear housing 57. In a discharge chamber 97 on the rear housing 57 side of the valve plate 91, a discharge valve 99 and a retainer 101 that regulates the valve lift amount are fastened to the valve plate 91 by bolts or the like.

  The rear housing 57 is provided with a control valve 103, and a control gas is introduced into the swash plate chamber 71 to adjust the inclination angle of the swash plate and set the discharge capacity. A passage for introducing control gas from the control valve 103 to the swash plate chamber 71 is formed in the cylinder block 55, the rear housing 57, the valve plate 91, etc., but is not shown here.

  Next, the shaft seal device 20 of this embodiment will be described. The shaft seal device 20 seals the periphery of the shaft 63. The shaft seal device 20 is a balanced shaft seal device. The shaft seal device 20 is provided in a shaft hole 53 b formed in the center portion of the bottom wall 53 a of the front housing 53. As shown in FIG. 2, the shaft seal device 20 includes a fixed ring 21, a rotating ring 22, a spring 27, and a bracket 28.

  The fixed ring 21 is made of, for example, silicon carbide, and is fixed to the shaft hole 53b. The shaft hole 53 b is formed in the front housing 53. The fixed ring 21 rotatably supports the shaft 63 inserted through the shaft hole 53b. The stationary ring 21 has an annular shape, and has a stationary-side seal end face 21a on the rotating ring 22 side (right side in the drawing).

  The rotary ring 22 is made of, for example, carbon, and is fixed to a shaft 63 located inside the front housing 53. The rotating ring 22 has an annular shape, and has a rotating side seal end face 22a on the stationary ring 21 side (left side in the figure). The rotating ring 22 rotates integrally with the shaft 63.

  The spring 27 is a coil spring, for example, and is fixed to the shaft 63 via the bracket 28. Further, the spring 27 urges the rotary ring 22 in the axial direction toward the front side (left side in the drawing) of the front housing 53.

  The bracket 28 forms a seating surface of the spring 27, is fixed to the shaft 63, and rotates integrally with the shaft 63 and the rotary ring 22.

  Further, U-rings 23 corresponding to sealing members are respectively provided on the contact surface (seal surface) of the shaft hole 53b of the housing of the fixed ring 21 and the front housing 53 and the contact surface (seal surface) of the rotary ring 22 and the shaft 63. Is provided.

  Specifically, a U-ring insertion groove 210 is formed on the outer peripheral surface of the fixed ring 21, and a flexible resin U-ring 23 is disposed in the U-ring insertion groove 210. The U ring 23 seals the contact surface (seal surface) between the stationary ring 21 and the shaft hole 53b of the front housing 53.

  In addition, a U-ring insertion groove 220 is formed on the inner peripheral surface of the rotary ring 22, and a flexible resin U-ring 23 is disposed in the U-ring insertion groove 220. The U-ring 23 seals the contact surface (seal surface) between the rotary ring 22 and the shaft 63. The configuration and material of each U-ring 23 are the same.

  FIG. 3 is a cross-sectional view of the contact surface between the rotating ring 22 and the shaft 63. FIG. 4 is a view showing a cross-sectional state of the U-ring 23 of the shaft seal device according to the present embodiment. The U ring 23 is an annular seal member having a U-shaped cross section in which a protrusion 23a and a protrusion 23b are formed on both outer sides of the opening. The U ring 23 is made of PTFE (polytetrafluoroethylene) which is a fluorocarbon resin.

  The U-ring 23 is disposed so that the opening faces the refrigerant side inside the housing. The U-ring 23 has a dimensional structure in which protrusions 23a and 23b formed on both outer sides of the opening are pressed against the seal surface by elasticity. That is, as shown in FIG. 5, when the pressure P of the refrigerant inside the housing increases, the U ring 23 is elastically deformed and the opening expands, and the shaft 63 and the rotating ring are extended to the protrusion 23a and the protrusion 23b. The force F which presses down 22 acts, and seals a sealing surface (contact surface of the rotating ring 22 and the shaft 63) with a strong force.

  Further, an annular metal spring member 230 is provided at the opening of the U-ring 23. This spring member 230 pushes and widens the opening of the U-ring 23. By this spring member 230, the protruding portion 23a and the protruding portion 23b of the U-ring 23 are pressed more strongly against the sealing surface.

  In addition, the spring member 230 in this embodiment has a W-shaped cross section. With this spring member 230, even when the pressure of the refrigerant inside the housing is low, the opening is widened so that the protrusion 23a and the protrusion 23b are pressed against the seal surface.

  In the above configuration, when the shaft 63 is rotated by an external driving force (for example, a vehicle engine), the lug plate 73 fixed to the shaft 63 is rotated, and the swash plate 77 connected by the pin 81 and the link mechanism portion 79 is rotated. . Here, the outer peripheral portion of the swash plate 77 is gripped by a shoe 89 so as to be slidable in the circumferential direction, and the shoe 89 is slidably engaged with a spherical bearing of the piston 85. Accordingly, the rotational swing motion of the swash plate 77 is converted into the reciprocating motion of the piston 85, and the fluid in the cylinder is discharged and sucked.

  In such a shaft seal device 20 of the swash plate compressor 51, (A) a contact surface between the fixed-side seal end surface 21a and the rotation-side seal end surface 22a, (B) a contact surface between the rotation ring 22 and the shaft 63, (C) At three locations on the contact surface of the shaft ring 53b of the stationary ring 21 and the housing of the front housing 53, seal portions that prevent leakage of the refrigerant to the outside are generated. Hereinafter, the seals shown in (A) to (C) will be described.

(A) When the seal shaft 63 of the contact surface between the fixed-side seal end surface 21a and the rotation-side seal end surface 22a rotates, the fixed-side seal end surface 21a of the fixed ring 21 and the rotation-side seal end surface 22a of the rotation ring 22 are connected to the spring 27 and The slider slides while being pressed by the refrigerant internal pressure of the compressor. In addition, lubricating oil is mixed in the carbon dioxide refrigerant used as the refrigerant, and this lubricating oil is drawn into the contact surface between the stationary seal end surface 21a of the stationary ring 21 and the rotational sealing end surface 22a of the rotating ring 22. An oil film is formed. Thus, the minute gap between the fixed-side seal end surface 21a and the rotation-side seal end surface 22a is filled with the lubricating oil, and the refrigerant in the housing is sealed so as not to leak to the outside.

  Further, even if the shaft 63 is displaced in the axial direction, the spring 27 allows the rotation ring 22 to move in the axial direction of the shaft 63, so that the fixed side seal end surface 21 a of the fixed ring 21 and the rotation side seal end surface of the rotation ring 22 are allowed. The 22a seal is maintained.

(B) Sealing of the contact surface between the rotating ring 22 and the shaft 63 The contact surface (seal surface) of the shaft 63 and the rotating ring 22 has a U-shaped cross section in which protrusions 23a and 23b are formed on both outer sides of the opening. An annular resin U-ring 23 is provided. Then, the protrusions 23a and 23b formed on both outer sides of the opening are pressed against the sealing surface by elasticity, and the sealing surfaces of the shaft 63 and the rotary ring 22 are sealed.

(C) Sealing of the contact surface between the fixed ring 21 and the shaft hole 53b of the front housing 53 The contact surface (seal surface) of the fixed ring 21 and the shaft hole 53b of the front housing 53 has protrusions 23a on both outer sides of the opening. An annular resin U-ring 23 having a U-shaped cross section with 23b formed therein is provided. Then, the protrusions 23 a and 23 b formed on both outer sides of the opening are pressed against the sealing surface by elasticity, and the sealing surface of the stationary ring 21 and the shaft hole 53 b of the front housing 53 is sealed.

  Since the swash plate compressor 51 employs carbon dioxide as a refrigerant, the shaft seal device 20 satisfies the four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance and cryogenic resistance. Is required.

  The two U rings 23 provided in the shaft seal device 20 of the present embodiment are each made of PTFE (polytetrafluoroethylene) which is a fluorocarbon resin. Here, with reference to FIG. 6, various characteristics comparison between various rubber materials and PTFE which is resin will be described.

  EPDM (ethylene propylene rubber) is inferior in all of heat resistance, carbon dioxide permeation resistance, foam resistance and cryogenic temperature. Moreover, although HNBR (nitrile rubber) for high temperature is excellent in heat resistance, carbon dioxide permeation resistance and cryogenic temperature, it is inferior in foaming resistance. Moreover, VMQ (silicone rubber) is inferior in carbon dioxide permeation resistance although it is excellent in heat resistance, foam resistance and cryogenic temperature. FKM (fluoro rubber) is excellent in heat resistance and carbon dioxide permeation resistance, but is inferior in foam resistance and cryogenic temperature. As described above, the rubber agent cannot satisfy the four requirements of heat resistance, carbon dioxide permeation resistance, foam resistance and cryogenic temperature.

  On the other hand, the two U-rings 23 provided in the shaft seal device 20 of the present embodiment are made of PTFE (polytetrafluoroethylene) which is a resin having flexibility, and this PTFE has heat resistance, It meets the four requirements of carbon dioxide permeation resistance, foam resistance and cryogenic temperature.

  According to the configuration described above, the shaft seal device 20 is a cross section in which the protrusions 23a and 23b are formed on the outer surfaces of the opening on the seal surface of the housing and the stationary ring 21 and the seal surface of the shaft 63 and the rotary ring 22, respectively. A U-shaped annular resin U-ring 23 is provided, and the U-ring 23 is disposed so that the opening faces the refrigerant side inside the housing, and the protrusions formed on both outer sides of the opening 23a and 23b are adapted to be pressed against the sealing surface by elasticity. Here, the U-ring 23 can be made of a resin that satisfies the four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance and cryogenic temperature resistance. Such a resin U-ring 23 can satisfy, for example, four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance, and cryogenic resistance that cannot be satisfied by a rubber material. Since the projecting portions 23a and 23b formed on both outer sides of the opening can be pressed against the sealing surface, the sealing performance of the sealing surface can be maintained for a longer period.

  Further, on the seal surface of the shaft 63 and the rotary ring 22, the rotary ring 22 biased by the spring 27 may move in the axial direction of the shaft 63 together with the shaft 63. By providing the above-described U-ring 23 on the sealing surface, it is possible to effectively perform the sealing.

  Moreover, as a resin that can satisfy the four requirements of heat resistance, foam resistance, carbon dioxide permeation resistance and cryogenic temperature resistance, for example, PTFE (polytetrafluoroethylene) can be used.

  The U-ring 23 has a spring member 230 that pushes the opening of the U-ring 23, and the protrusions 23a and 23b are pressed against the seal surface by the spring member 230. Even when the pressure of the refrigerant is low, sealing performance can be ensured.

(Second Embodiment)
Hereinafter, a compressor and a shaft seal device according to a second embodiment of the present invention will be described with reference to FIGS. The U-ring 23 in the first embodiment has a spring member 230 having a W-shaped cross section, but the U-ring 24 in the present embodiment has two annular plate springs having different diameters. Members 240 and 241 are provided. The U-ring 24 is an annular seal member having a U-shaped cross section in which a protrusion 24a and a protrusion 24b are formed on both outer sides of the opening.

  Each of the spring members 240 and 241 is formed by forming a thin metal plate into an annular shape, and is elastically deformed.

  The outer spring member 240 is slightly larger than the outer peripheral side surface of the opening of the U-ring 24, and when arranged on the opening of the U-ring 24, as shown in FIG. Works.

  Further, the inner spring member 241 is slightly smaller than the inner peripheral side surface of the opening of the U-ring 24, and when arranged on the opening of the U-ring 24, as shown in FIG. Force acts in the direction.

  With these spring members 240 and 241, even when the pressure of the refrigerant inside the housing is low, the opening is widened so that the protrusion 24a and the protrusion 24b are pressed against the seal surface.

  Such U-rings 24 are provided on a contact surface (seal surface) of the shaft hole 53b of the stationary ring 21 and the front housing 53, and on a contact surface (seal surface) of the rotary ring 22 and the shaft 63, respectively.

  In this embodiment, the effect produced from the configuration common to the first embodiment can be obtained in the same manner as in the first embodiment.

  In addition, the U-ring 24 including the spring members 240 and 241 formed of a metal thin plate in an annular shape as in the present embodiment can be reduced in cost because of its simple configuration. Miniaturization is also possible.

  In addition, although this embodiment is embodiment based on 1st Embodiment, it is also possible to combine this embodiment with either of the above-mentioned 1st Embodiment.

(Third embodiment)
Hereinafter, a compressor and a shaft seal device according to a third embodiment of the present invention will be described with reference to FIGS. 9 and 10. Although the cross section of the spring member 230 of the U ring 23 in the first embodiment is W-shaped, the cross section of the spring member 250 of the U ring 25 in the present embodiment is U-shaped. The U-ring 25 is a seal member having a U-shaped cross section in which a protrusion 25a and a protrusion 25b are formed on both outer sides of the opening.

  The spring member 250 is formed by forming an annular metal thin plate having a U-shaped cross section. When the spring member 250 is disposed in the opening of the U-ring 24, a force acts in the direction of opening the opening of the spring member 250 as shown in FIG.

  Even when the pressure of the refrigerant inside the housing is low, the spring member 250 expands the opening so that the protrusion 25a and the protrusion 25b are pressed against the seal surface.

  Such U-rings 25 are provided on the contact surface (seal surface) of the shaft hole 53b of the stationary ring 21 and the front housing 53 and on the contact surface (seal surface) of the rotary ring 22 and the shaft 63, respectively.

  In this embodiment, the effect produced from the configuration common to the first embodiment can be obtained in the same manner as in the first embodiment.

  Further, since the U-ring 25 including the spring member 250 having a U-shaped cross section as in the present embodiment has a simple configuration, the cost can be reduced, and the shaft seal device 20 can be downsized. Is possible.

  In addition, although this embodiment is embodiment based on 1st Embodiment, it is also possible to combine this embodiment with either of the above-mentioned 1st Embodiment.

(Other embodiments)
In the first to third embodiments, the compressor of the present invention has been described by taking a swash plate compressor using carbon dioxide as a refrigerant as an example, but it can be applied to various compressors other than the swash plate compressor. it can.

  Moreover, in the said 1st-3rd embodiment, although the balance type shaft seal apparatus was demonstrated to the example, it is not limited to such a type shaft seal apparatus, For example, an unbalanced shaft seal apparatus It can also be applied to.

  Moreover, in the said 1st-3rd embodiment, although the U rings 23-25 have a U-shaped cross section, you may make it a cross section become a V shape, for example.

  In the first to third embodiments, the spring members 230, 240, 241, and 250 are provided in the openings of the U rings 23 to 25. However, it is not always necessary to provide such spring members. .

  Moreover, in the said 1st-3rd embodiment, although the U rings 23-25 were comprised by PTFE (polytetrafluoroethylene), heat resistance other than PTFE, foam resistance, carbon dioxide permeation resistance, and cryogenic resistance You may comprise by resin satisfying these four requirements.

  The U-ring 23 of the first embodiment includes a spring member 230 having a W-shaped cross section, and the U-ring 25 of the second embodiment includes a spring member 250 having a U-shaped cross section. However, for example, the U-ring may be provided with a spring member having a V-shaped cross section.

  In the first to third embodiments, the U-rings 23 to 25 are provided on the sealing surfaces of the housing 53 and the stationary ring 21 and the sealing surfaces of the shaft 63 and the rotating ring 22. U rings 23 to 25 may be provided on any one of the sealing surface of the stationary ring 21 and the sealing surface of the shaft 63 and the rotating ring 22. Further, a U-ring may be provided on the seal surface of the shaft 63 and the rotary ring 22, and for example, the seal surface of the housing 53 and the fixed ring 21 may be joined so that the sealing performance is maintained.

  In the first to third embodiments, the U-rings 23 to 25 are provided on the contact surface of the stationary ring 21 with the front housing 53, but the U-rings 23 to 25 are disposed on the contact surface of the front housing 53 with the stationary ring 21. 25 may be provided. In the first and second embodiments, the U-rings 23 to 25 are provided on the contact surface of the rotating ring 22 with the shaft 63. However, the U-rings 23 to 25 are provided on the contact surface of the shaft 63 with the rotating ring 22. It may be provided.

  In addition, this invention is not limited to above-described embodiment, In the range described in the claim, it can change suitably. In each of the above embodiments, when referring to the material, shape, positional relationship, etc. of the constituent elements, etc., unless otherwise specified, or in principle limited to a specific material, shape, positional relationship, etc. The material, shape, positional relationship, etc. are not limited.

DESCRIPTION OF SYMBOLS 20 Shaft seal device 21 Fixed ring 21a Fixed side seal end surface 22 Rotating ring 22a Rotation side seal end surface 27 Spring 28 Bracket 23a-25a, 23b-25b Protrusion part 23-25 U-ring 230, 240, 241, 250 Spring member 51 Swash plate Type compressor 53 Front housing 57 Rear housing 63 Shaft

Claims (7)

A shaft seal device (20) of a compressor (51) for compressing carbon dioxide refrigerant,
A rotating ring (22) fixed to a shaft (63) located inside a housing (53, 55, 57) containing the refrigerant;
A fixed ring (21) fixed to a shaft hole (53b) formed in the housing and rotatably supporting the shaft inserted through the shaft hole;
At least one of the sealing surface of the housing and the stationary ring and the sealing surface of the shaft and the rotating ring has an opening, and protrusions (23a to 25a, 23b to 25b) on both outer sides of the opening. An annular resin sealing member (23-25) formed with
The seal member is arranged such that the opening faces the refrigerant side inside the housing, and the protrusions formed on both outer sides of the opening are pressed against the seal surface by elasticity. A shaft seal device.   The shaft seal device according to claim 1, wherein the seal member is a U-ring having a U-shaped cross section.   The shaft seal device according to claim 1, wherein the seal member is provided on a seal surface of the shaft and the rotary ring.   The shaft seal device according to any one of claims 1 to 3, wherein the seal member is made of PTFE.   The seal member has a spring member (230, 240, 241, 250) that pushes the opening of the seal member, and the protrusion is pressed against the seal surface by the spring member. The shaft seal device according to any one of claims 1 to 4.   The shaft sealing device according to claim 5, wherein the spring member has a U-shaped, V-shaped, or W-shaped cross section.   A compressor using the shaft seal device according to any one of claims 1 to 6 for sealing around the shaft.

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