WO2016132692A1

WO2016132692A1 - Shaft-sealing device

Info

Publication number: WO2016132692A1
Application number: PCT/JP2016/000549
Authority: WO
Inventors: 秋山　訓孝; 亨大隈
Original assignee: 株式会社デンソー
Priority date: 2015-02-17
Filing date: 2016-02-03
Publication date: 2016-08-25
Also published as: JP6455209B2; JP2016151311A; DE112016000784T5

Abstract

A shaft-sealing device is provided with: a rotating ring (51) fixed to the outer circumference of a shaft (30); a fixed ring (52) fixed on the circumference of a shaft hole (41c) of a housing (40) and in surface contact with the rotating ring (51); a lip seal (53), the outer circumference of which is fixed to the housing (40) and the inner circumference of which contacts the shaft (30); and a bimetal (54) for changing the lip seal (53) from a shape that contacts the shaft (30) to a shape that does not contact same as temperature increases. As a result, when a compressor (10) is stopped and the bimetal (54) has a low temperature, sealing is improved by bringing the lip seal (53) into contact with the shaft (30) and when the compressor (10) is operating and the bimetal has a high temperature, the lip seal (53) is protected by keeping the lip seal (53) from contacting the shaft (30).

Description

Shaft seal device

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2015-028747 filed on Feb. 17, 2015, the disclosure of which is incorporated into this application by reference.

The present disclosure relates to a shaft seal device applied to a compressor that compresses a fluid.

Conventionally, Patent Document 1 discloses a shaft seal device applied to a compressor that compresses carbon dioxide as a refrigerant in a vapor compression refrigeration cycle apparatus.

The shaft seal device of Patent Document 1 includes a rotary ring fixed to a rotary shaft of a compressor, and a fixed ring fixed around a shaft hole provided in a housing of the compressor. By bringing the stationary ring into surface contact, the refrigerant in the housing is prevented from leaking outside through the gap between the rotating ring and the stationary ring.

Furthermore, in the shaft seal device applied to the compressor of the refrigeration cycle apparatus, when the compressor is operated, the refrigeration oil enclosed in the refrigeration cycle apparatus together with the refrigerant is caused to flow into the gap between the rotating ring and the stationary ring. Can do. Thereby, a clearance gap can be filled up with highly viscous refrigerating machine oil, and the sealing performance of a shaft seal apparatus can be improved.

Here, as in Patent Document 1, in a refrigeration cycle apparatus that constitutes a supercritical refrigeration cycle that employs carbon dioxide as a refrigerant and the pressure of the high-pressure side refrigerant of the cycle is equal to or higher than the critical pressure of the refrigerant, The pressure difference between the refrigerant pressure and the atmospheric pressure outside the housing becomes relatively large. For this reason, the improvement of the sealing performance of the shaft seal device by the refrigerating machine oil described above is effective.

Japanese Patent Laid-Open No. 2007-9886

However, according to the study by the inventors, in the compressor of the refrigeration cycle apparatus, a so-called “refrigerant stagnation phenomenon” occurs in which liquid refrigerant accumulates in the housing when the operation is stopped for a long time. When such a phenomenon occurs, the refrigerating machine oil having compatibility with the liquid phase refrigerant is diluted, so that the viscosity of the refrigerating machine oil is significantly reduced. As a result, the refrigerating machine oil cannot fill the gap between the rotating ring and the stationary ring, and the sealing performance of the gap cannot be improved.

On the other hand, in addition to the shaft seal device, for example, the outer peripheral side of an annular lip seal formed of rubber or the like is fixed to the housing, and the inner peripheral side of the lip seal is brought into contact with the periphery of the rotating shaft. Thus, a means for improving the sealing performance can be considered. However, the lip seal is likely to be worn or damaged when the rotating shaft rotates. For this reason, when adding a lip seal, there exists a possibility that it may be difficult to maintain a sealing performance over a long period of time.

In view of the above points, it is an object of the present disclosure to provide a highly durable shaft seal device that exhibits high sealing performance regardless of the rotation state of the rotation shaft of the compressor. A shaft seal device according to a feature example of the present disclosure is applied to a compressor having a housing that forms a space in which a part of a rotating shaft is accommodated, and includes a shaft hole provided in the housing and a rotating shaft. It is possible to suppress leakage of the fluid to be compressed in the housing from the gap. The shaft sealing device includes an annular rotating ring fixed to the outer peripheral side of the rotating shaft and an annular ring fixed to the periphery of the shaft hole of the housing and in surface contact with the rotating ring when the rotating shaft is inserted into the shaft hole. When the fixed ring, the rotation shaft and the member fixed thereto are defined as the rotation shaft side member, and the housing and the member fixed thereto are defined as the housing side member, the rotation shaft side member and the housing side An annular lip seal fixed to one of the members and arranged so as to be in contact with the other, and a shape in which the lip seal is brought into contact with the other of the housing side member and the rotary shaft side member as the temperature rises. And a deforming portion that is deformed into a shape.

According to this, since the rotating ring and the stationary ring are in surface contact with each other during the operation of the compressor whose rotating shaft is rotating, the fluid to be compressed in the housing leaks to the outside like a so-called mechanical seal. Can be suppressed.

At this time, when the compressor is activated and the temperature of the deformed portion becomes high, the shape of the lip seal changes to a non-contact state with the rotating shaft side member or the housing side member due to the action of the deformed portion. Therefore, even if the rotating shaft rotates, it is possible to suppress the lip seal from being worn or damaged.

On the other hand, when the compressor whose rotating shaft is stopped is stopped, the temperature of the deforming portion is lowered, so that the lip seal is deformed into a shape in contact with the rotating shaft side member or the housing side member by the action of the deforming portion.

Therefore, even when applied to a compressor in which the sealing performance of the gap between the rotating ring and the stationary ring is likely to be lowered when the rotating shaft is stopped, the lip seal causes the fluid to be compressed in the housing. Can be prevented from leaking outside.

Therefore, it is possible to provide a highly durable shaft seal device that can exhibit high sealing performance regardless of the rotation state of the rotary shaft of the compressor and can suppress wear and damage of the lip seal.

For example, the rotating shaft side member corresponds to a rotating shaft, a rotating ring, and the like, and the housing side member corresponds to a housing, a fixed ring, and the like.

It is an axial sectional view of the compressor of a 1st embodiment. It is an expanded sectional view of the II section of FIG. It is an expanded sectional view of the III section of Drawing 2, Comprising: It is a typical expanded sectional view showing the shape of a lip seal at the time of operation of the compressor of a 1st embodiment. FIG. 3 is an enlarged cross-sectional view of a part III in FIG. 2, and is a schematic enlarged cross-sectional view showing a shape of a lip seal when the compressor of the first embodiment is stopped. It is an expanded sectional view corresponding to Drawing 2 of a 2nd embodiment. It is an expanded sectional view corresponding to Drawing 2 of a 3rd embodiment. It is a typical expanded sectional view of the lip seal of 4th Embodiment.

(First embodiment)
A first embodiment of the present disclosure will be described with reference to FIGS. The shaft seal device 50 of the present embodiment is applied to a compressor 10 that compresses and discharges a refrigerant that is a compression target fluid in a vapor compression refrigeration cycle apparatus. The refrigeration cycle apparatus of the present embodiment is applied to a vehicle air conditioner, and fulfills a function of cooling blown air blown into the vehicle interior.

Also, this refrigeration cycle apparatus employs carbon dioxide as a refrigerant, and constitutes a so-called supercritical refrigeration cycle in which the refrigerant pressure on the high pressure side of the cycle is equal to or higher than the critical pressure of the refrigerant. Furthermore, refrigeration oil for lubricating the sliding part of the compressor 10 is mixed in the refrigerant, and at least a part of the refrigeration oil circulates in the cycle together with the refrigerant. As this refrigeration oil, what has compatibility with a liquid phase refrigerant is adopted.

Next, the compressor 10 will be described. As shown in FIG. 1, the compressor 10 is configured as a swash plate type variable displacement compressor. The compressor 10 includes a compression mechanism unit 20 that compresses and discharges a refrigerant, a shaft 30 that is a rotation shaft that transmits a rotational driving force output from the engine to the compression mechanism unit 20, and a compression mechanism unit 20 and a shaft therein. And a housing 40 that forms a space for accommodating a part of the housing 30 and the like.

More specifically, the housing 40 of this embodiment is formed in a bottomed cylindrical shape by combining a plurality of constituent members such as a front housing 41, a middle housing 42, a rear housing 43, and the like.

The front housing 41 is formed of a cup-shaped metal member and forms a control pressure chamber 41a therein. The rear housing 43 is formed of a cup-shaped metal member, and forms a discharge chamber 43a and the like into which the refrigerant discharged from the compression mechanism unit 20 flows. The middle housing 42 is arranged between the front housing 41 and the rear housing 43 so as to close both openings of the front housing 41 and the rear housing 43, and forms the cylinder 21 of the compression mechanism section 20. It is.

At the center of the bottom surface of the front housing 41, a cylindrical boss 41b protruding in the central axis direction is formed. A pulley (not shown) is rotatably attached to the outer peripheral surface of the boss portion 41b via a bearing member such as a bearing. A rotational driving force output from the engine is transmitted to the pulley via the belt.

Furthermore, a shaft hole 41c that penetrates the inside and outside of the front housing 41 is formed at the center of the boss 41b formed on the bottom surface of the front housing 41. The shaft 30 is inserted into the shaft hole 41c.

The shaft 30 is formed of a substantially cylindrical member made of metal, and the central axis thereof is disposed substantially parallel to the central axis of the housing 40. Furthermore, a part of the shaft 30 protrudes outward from the shaft hole 41c of the front housing 41 and is connected to a pulley. Thereby, the rotational driving force output from the engine is transmitted to the shaft 30 via the pulley. Of course, an electromagnetic clutch for intermittently connecting the pulley and the shaft 30 may be interposed at the connecting portion between the pulley and the shaft 30.

The remaining part of the shaft 30 is arranged so as to penetrate the inside of the control pressure chamber 41a, and the lug plate 22 extending in the radial direction is fixed to the part accommodated in the control pressure chamber 41a. Therefore, the lug plate 22 rotates with the shaft 30. Furthermore, the link part 23 is provided in the outer peripheral side of the lug plate 22, The swash plate 24 is connected with this link part 23 so that the inclination angle with respect to the central axis of the shaft 30 can be changed.

A plurality of pistons 26 that reciprocate in parallel with the central axis of the shaft 30 are connected to the swash plate 24 via a shoe 25 that is a spherical bearing. The plurality of pistons 26 reciprocate inside the plurality of cylinders 21 formed in the middle housing 42 in conjunction with the rotation of the swash plate 24. Thereby, the refrigerant is sucked into the compression chamber surrounded by the end face of the piston 26 and the inner wall of the cylinder 21, and the sucked refrigerant is compressed.

Further, in the compression mechanism unit 20 of the present embodiment, the stroke of the reciprocating motion of the piston 26 can be changed by changing the inclination angle of the swash plate 24. The discharge capacity can be changed by changing the stroke amount. The discharge capacity is the geometric volume of the compression chamber, that is, the cylinder volume between the top dead center and the bottom dead center of the piston stroke.

The inclination angle of the swash plate 24 includes the pressure acting on the front and rear of the piston 26, the refrigerant pressure Pc in the space in which the swash plate and the like in the housing 40 are accommodated (that is, the control pressure chamber 41a in the front housing 41), and the compression chamber. Can be changed according to a balance with the pressure (refrigerant discharge pressure Pd and refrigerant suction pressure Ps).

Further, the refrigerant pressure Pc in the control pressure chamber 41a adjusts the valve opening degree of the electromagnetic capacity control valve 27 attached to the rear housing 43, and the refrigerant discharge pressure Pd and the suction pressure Pd introduced into the control pressure chamber 41a. This is done by changing the introduction ratio. The opening degree of the electromagnetic capacity control valve 27 is controlled by a control current output from an air conditioning control device (not shown).

Here, as described above, a plurality of cylinders 21 are formed in the middle housing 42 of the present embodiment, and the same number of pistons 26 as the cylinders 21 are connected to the swash plate 24. On the other hand, in FIG. 1, for clarity of illustration, a pair of cylinders 21 and pistons 26 is illustrated, and the remaining cylinders 21 and pistons 26 are not illustrated.

Next, referring to FIG. 2, a shaft that suppresses leakage of refrigerant in the housing 40 (specifically, in the control pressure chamber 41 a) from the gap between the shaft hole 41 c provided in the housing 40 and the shaft 30. The sealing device 50 will be described.

The shaft seal device 50 according to the present embodiment includes an annular rotary ring 51 fixed to the outer peripheral side of the shaft 30, an annular fixed ring 52 fixed around the shaft hole 41 c of the front housing 41, and the front housing 41. It is configured to have a lip seal 53 or the like that is fixed to the inner peripheral side (housing side member) of the boss portion 41b and arranged so as to be in contact with the outer peripheral surface (rotary shaft side member) of the shaft 30.

Rotating ring 51 is formed of an annular member made of silicon carbide (silicon carbide). The outer peripheral side of the rotating ring 51 is supported by a guide member 55 formed of an annular metal member. The guide member 55 is fixed to the shaft 30 and restricts the displacement of the rotating ring 51 in the rotation direction.

A spring 55 a that is an elastic member is disposed between the guide member 55 and the rotating ring 51. The spring 55a applies a load that biases the rotating ring 51 toward one end side in the axial direction of the shaft 30 (the end portion side on the shaft hole 31 side). Further, an O-ring 51 a as a seal member is disposed between the inner peripheral surface of the rotary ring 51 and the outer peripheral surface of the shaft 30, and the inner peripheral surface of the rotary ring 51 and the outer peripheral surface of the shaft 30 are arranged. There is no leakage of refrigerant.

The fixed ring 52 is formed of an annular member made of silicon carbide similarly to the rotating ring 51. The stationary ring 52 is disposed on one axial end side of the shaft 30 with respect to the rotating ring 51 and is disposed so as to be in surface contact with the rotating ring 51.

In the present embodiment, when the shaft 30 is assembled to the housing 40 and inserted into the shaft hole 41c, the rotating ring 51 receives a load from the spring 55a, thereby reliably bringing the rotating ring 51 and the stationary ring 52 into surface contact. Can do. At this time, a contact surface (seal surface) between the rotating ring 51 and the stationary ring 52 is formed in an annular shape around the shaft 30.

Further, an O-ring 52 a as a seal member is disposed between the outer peripheral surface of the fixed ring 52 and the inner peripheral surface of the boss portion 41 b of the housing 40, and the outer peripheral surface of the fixed ring 52 and the boss of the housing 40 are disposed. The refrigerant does not leak from the space between the inner peripheral surface of the portion 41b.

As is clear from the above description, the guide member 55, the spring 55 a, the rotating ring 51, the lug plate 22, and the like of this embodiment rotate integrally with the shaft 30. Therefore, the shaft 30, the guide member 55, the rotating ring 51, and the like constitute a rotating shaft side member described in the claims. On the other hand, the housing 40, the stationary ring 52, and the like constitute a housing side member described in the claims.

Next, the lip seal 53 will be described. The lip seal 53 is made of rubber having excellent heat resistance (specifically, HNBR: hydrogenated nitrile rubber). Further, the lip seal 53 is disposed on one end side in the axial direction of the shaft 30 with respect to the fixed ring 52 in a state of being integrated with the annular metal protection member 53a.

For this reason, the lip seal 53 is disposed downstream of the contact surface between the rotating ring 51 and the stationary ring 52 in the refrigerant leakage direction. In other words, the lip seal 53 is disposed on the outer side of the housing 40 with respect to the contact surface between the rotating ring 51 and the fixed ring 52. As shown in FIG. 2, the lip seal 53 extends beyond the contact surface between the rotating ring 51 and the fixed ring 52 to the outside of the diameter of the rotating shaft 30.

The protective member 53a has a disk-shaped part 53b that spreads in the radial direction of the shaft 30, and a cylindrical part 53c provided on the outer peripheral side of the disk-shaped part. And the axial direction both ends of the cylindrical part 53c are sandwiched between the annular projecting part 41d formed on the inner peripheral side of the boss part 41b and the surface of one end side in the axial direction of the stationary ring 52, The lip seal 53 and the protective member 53a are fixed inside the boss portion 41b.

At this time, the lip seal 53 is slightly crushed in the axial direction by the fixed ring 52, but the deformation amount is restricted by the cylindrical portion 53c. As a result, leakage from the gap between the lip seal 53 and the stationary ring 52 is suppressed, and unnecessary deformation of the lip seal 53 can be suppressed to protect the lip seal 53. Furthermore, since the disk-shaped part 53b is provided in the protection member 53a, it is possible to suppress the lip seal 53 from being bent to the outside of the housing 40.

Further, as shown in FIG. 2, the tip portion on the inner peripheral side of the lip seal 53 is inclined so as to gradually approach the shaft 30 toward the inner side of the housing 40 in the axial section. Thus, when the refrigerant leaks from the inside of the housing 40, the tip of the lip seal 53 is pressed against the outer peripheral surface of the shaft 30 by the pressure of the refrigerant, and the leakage from the gap between the lip seal 53 and the shaft 30 is suppressed. It is possible to improve the sealing performance.

Furthermore, a bimetal 54 is integrally formed in the lip seal 53 of this embodiment by insert molding. The bimetal 54 is a laminate of two types of metal plates having different coefficients of thermal expansion, and changes to a specific shape according to a temperature change.

More specifically, in the present embodiment, as the bimetal 54 increases in temperature as the bimetal 54 itself increases, as shown in FIG. 3, the inner peripheral side of the lip seal 53 comes into contact with the shaft 30, as shown in FIG. As shown in FIG. 4, a shape is adopted in which the inner peripheral side of the lip seal 53 is deformed into a shape that does not contact the shaft 30, that is, a non-contact shape.

This is because, as the bimetal 54, the lip seal 53 is moved to the shaft as the temperature of the portion (the refrigerant around the lip seal 53 (fluid to be compressed) or the portion where the lip seal 53 contacts) that transmits heat to the bimetal 54 increases. It can also be expressed that a shape that deforms from a shape that contacts 30 to a shape that does not contact is adopted.

Therefore, the bimetal 54 of the present embodiment constitutes an example of a deformed portion of the present application. FIG. 2 also shows a state where the temperature of the bimetal 54 itself has not risen, as in FIG. Further, as in the present embodiment, in the compressor 10 mounted on the vehicle, when the temperature of the bimetal 54 itself becomes at least 50 ° C. or more, the inner peripheral side of the lip seal 53 is deformed into a shape that does not contact the shaft 30. It is desirable to adopt one.

Next, the operation and effect of this embodiment in the above configuration will be described. In the compressor 10 of this embodiment, the shaft 30 rotates by transmitting the rotational driving force output from the engine. Then, when the rotational driving force is transmitted from the shaft 30 to the compression mechanism unit 20, the compression mechanism unit 20 compresses and discharges the refrigerant.

At this time, according to the shaft seal device 50 of the present embodiment, since the rotary ring 51 and the fixed ring 52 are in surface contact with each other at the contact surface formed in an annular shape, the inside of the housing 40 is similar to a so-called mechanical seal. The refrigerant can be prevented from leaking outside.

Furthermore, since the refrigeration oil is mixed in the refrigerant of the refrigeration cycle apparatus of the present embodiment, the refrigeration oil can flow into the gap between the rotating ring 51 and the stationary ring 52. Thereby, the clearance gap between the rotating ring 51 and the stationary ring 52 can be filled with highly viscous refrigerating machine oil, and the sealing performance of the shaft seal device 50 can be improved effectively.

Here, when the compressor 10 is operating, the temperature of the refrigerant and the compressor 10 rises due to a temperature rise due to adiabatic compression of the refrigerant, friction of a sliding portion in the compressor 10, and the like. For this reason, in the shaft seal device 50 of this embodiment, this temperature rise is transmitted to the bimetal 54 via the contact portion between the refrigerant and the bimetal 54. The lip seal 53 is deformed into a shape that does not come into contact with the shaft 30 due to deformation accompanying the temperature rise of the bimetal 54.

Therefore, it is possible to prevent the lip seal 53 from being worn or damaged due to friction between the lip seal 53 and the shaft 30 during the operation of the compressor 10 in which the shaft 30 rotates.

By the way, in a compressor applied to a refrigeration cycle apparatus, in general, a gas phase refrigerant is sucked, compressed, and discharged during normal operation. However, when the compressor is stopped for a long time, a “refrigerant stagnation phenomenon” occurs in which liquid-phase refrigerant accumulates in the housing. When such a phenomenon occurs, the refrigerating machine oil having compatibility with the liquid phase refrigerant is diluted, so that the viscosity of the refrigerating machine oil is significantly reduced.

As a result, the refrigerating machine oil may not be able to fill the gap between the rotating ring 51 and the stationary ring 52, and the sealing performance of the gap between the rotating ring 51 and the stationary ring 52 may not be improved.

On the other hand, according to the shaft seal device 50 of the present embodiment, when the rotation of the shaft 30 is stopped and the compressor 10 is stopped, the temperature of the bimetal 53 is lowered. The shape is deformed to contact the shaft 30. Therefore, when the operation of the compressor 10 is stopped, the lip seal 53 can prevent the refrigerant in the housing 40 from leaking outside.

That is, according to the shaft seal device 50 of the present embodiment, high sealing performance can be exhibited regardless of the operating state of the compressor 10 (rotation state of the shaft 30), and wear and damage of the lip seal 53 are suppressed. A highly durable shaft seal device can be provided.

Further, in the shaft seal device 50 of the present embodiment, the lip seal 53 and the protective member 53a are arranged outside the housing 40 rather than the contact surface between the rotating ring 51 and the fixed ring 52. It is easy to adopt a configuration in which the inner peripheral side is in direct contact with the shaft 30. Therefore, the lip seal 53, the protection member 53 a, and the bimetal 54 can be prevented from being enlarged, and the shape can be easily assembled in the housing 40.

Further, in the shaft seal device 50 of the present embodiment, the bimetal 54 and the lip seal 53 are integrally formed by insert molding. Accordingly, it is possible to easily realize a deformed portion that deforms the lip seal 53 from a shape that contacts the shaft 30 to a shape that does not contact the shaft 30 as the temperature rises.

Further, as in the present embodiment, in the refrigeration cycle apparatus that constitutes the supercritical refrigeration cycle using carbon dioxide as the refrigerant, the pressure difference between the refrigerant pressure in the housing 40 of the compressor 10 and the atmospheric pressure outside the housing 40. Is relatively large. Therefore, the refrigerant is more likely to leak from the gap between the rotating ring 51 and the stationary ring 52 than a refrigeration cycle apparatus that employs normal chlorofluorocarbon refrigerants (R134a, R1234yf, etc.).

Therefore, as in this embodiment, when the compressor 10 is in operation, the refrigerating machine oil can improve the sealing performance of the gap between the rotating ring 51 and the stationary ring 52, and when the compressor 10 is stopped, the lip seal 53 It is extremely effective that the refrigerant in the housing 40 can be prevented from leaking outside.

(Second Embodiment)
This embodiment demonstrates the example which changed the arrangement | positioning aspect of the lip seal 53 and the bimetal 54 with respect to 1st Embodiment, as shown in FIG. FIG. 5 is a drawing corresponding to FIG. 2 described in the first embodiment, and the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

More specifically, the lip seal 53 and the bimetal 54 of the present embodiment are integrated by insert molding as in the first embodiment. Further, as shown in FIG. 5, the lip seal 53 is fixed to a portion closer to the control pressure chamber side than the boss portion 41 d in the housing 40, and the inner peripheral side thereof is disposed so as to be in contact with the outer peripheral surface of the shaft 30. ing.

For this reason, the lip seal 53 of the present embodiment is arranged upstream of the contact surface between the rotating ring 51 and the stationary ring 52 in the refrigerant leakage direction. In other words, the lip seal 53 is disposed on the inner side of the housing 40 with respect to the contact surface between the rotating ring 51 and the fixed ring 52.

Other configurations of the compressor 10 and the shaft seal device 50 are the same as those in the first embodiment. Accordingly, in the shaft seal device 50 of the present embodiment, as in the first embodiment, a high sealing performance can be exhibited regardless of the operating state of the compressor 10 (the rotation state of the shaft 30), and the lip seal It is possible to provide a highly durable shaft seal device capable of suppressing the wear and damage of 53.

Furthermore, in the shaft seal device 50 of the present embodiment, the lip seal 53 is disposed on the inner side of the housing 40 with respect to the contact surface between the rotating ring 51 and the fixed ring 52. Accordingly, when the rotation of the shaft 30 is stopped and the lip seal 53 is deformed into a shape in contact with the shaft 30, the seal portion between the lip seal 53 and the shaft 30 reaches the seal portion between the rotating ring 51 and the fixed ring 52. The refrigerant pressure in the range is unlikely to rise.

As a result, when the rotation of the shaft 30 is stopped and the operation of the compressor 10 is stopped, the refrigerant in a range from the seal portion between the lip seal 53 and the shaft 30 to the seal portion between the rotary ring 51 and the fixed ring 52 is discharged. It is possible to suppress leakage to the outside.

(Third embodiment)
This embodiment demonstrates the example which changed the arrangement | positioning aspect of the lip seal 53 and the bimetal 54 with respect to 1st Embodiment, as shown in FIG. FIG. 6 is a drawing corresponding to FIG. 2 described in the first embodiment.

More specifically, the lip seal 53 and the bimetal 54 of the present embodiment are integrated by insert molding as in the first embodiment. Further, as shown in FIG. 6, the lip seal 53 is fixed to the rotary ring 51 (rotary shaft side member), and the outer peripheral side thereof is disposed so as to be able to contact the fixed ring 52 (housing side member).

(Fourth embodiment)
In the above-described embodiment, the example in which the lip seal 53 and the bimetal 54 are integrated by insert molding has been described. However, in this embodiment, as shown in FIG. 7, the lip seal 53 and the bimetal 54 configured as separate members. An example in which these are integrated so as to be integrally deformed will be described. FIG. 7 is a drawing corresponding to FIG. 3 described in the first embodiment.

More specifically, on the outer surface of the lip seal 53 of the present embodiment, locking

portions

53b and 53c for locking the bimetal 54 at the outer peripheral end and the inner peripheral end are formed. Thereby, the bimetal 54 and the lip seal 53 are integrally deformed. That is, with the deformation of the bimetal 54, the lip seal 53 is similarly deformed.

Other configurations of the compressor 10 and the shaft seal device 50 are the same as those in the first embodiment. Accordingly, in the shaft seal device 50 of the present embodiment, as in the first embodiment, a high sealing performance can be exhibited regardless of the operating state of the compressor 10 (the rotation state of the shaft 30), and the lip seal It is possible to provide a highly durable shaft seal device capable of suppressing the wear and damage of 53. Further, the lip seal 53 and the bimetal 54 may be joined with an adhesive or the like.

(Other embodiments)
The present disclosure is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present disclosure. Further, the means disclosed in each of the above embodiments may be appropriately combined within a practicable range. For example, the lip seal 53 and the bimetal 54 integrated as described in the fourth embodiment may be employed in the shaft seal device 50 described in the second and third embodiments.

In the above-described embodiment, an example in which a swash plate type variable displacement compression mechanism is employed as the compression mechanism unit 20 of the compressor 10 has been described. However, the compression mechanism unit 20 is not limited thereto. For example, any compression mechanism that compresses fluid by transmitting a rotational driving force from the shaft 30 such as a scroll-type compression mechanism, a vane-type compression mechanism, or a rolling piston-type compression mechanism can be widely used.

In the above-described embodiment, the example in which the bimetal is adopted as the deforming portion has been described, but the deforming portion is not limited to this. For example, if the shape of the lip seal 53 can be deformed to a desired shape according to a temperature change, the deforming portion is formed by joining two types of resin plates having different thermal expansion coefficients. Alternatively, it may be formed by bonding resins and metals having different thermal expansion coefficients.

In the above-described embodiment, the example in which the rotating ring 51 and the stationary ring 52 formed of silicon carbide are used has been described. However, the material of the rotating ring 51 and the stationary ring 52 is not limited thereto. For example, it may be formed of carbon fiber or a carbon fiber reinforced composite material. Moreover, although the above-mentioned embodiment demonstrated the example which employ | adopted the lip seal 53 formed with rubber | gum, the material of the lip seal 53 is not limited to this. For example, you may form with resin.

Moreover, in the above-described embodiment, the example in which the shaft seal device 50 according to the present disclosure is applied to the compressor 10 of the refrigeration cycle device that employs carbon dioxide as a refrigerant has been described. It is not limited. Of course, the present invention may be applied to a compressor of a refrigeration cycle apparatus constituting a subcritical refrigeration cycle in which the refrigerant pressure on the high pressure side does not exceed the critical pressure of the refrigerant, or can be applied to compressors for a wide variety of other uses.

Claims

Applied to the compressor (10) having a housing (40) that forms a space in which a part of the rotating shaft (30) is accommodated,
A shaft seal device that suppresses leakage of a fluid to be compressed in the housing (40) from a gap between a shaft hole (41c) provided in the housing (40) and the rotating shaft (30),
An annular rotating ring (51) fixed to the outer peripheral side of the rotating shaft (30);
An annular ring is fixed around the shaft hole (41c) of the housing (40) and comes into surface contact with the rotating ring (51) when the rotating shaft (30) is inserted into the shaft hole (41c). A stationary ring (52);
The rotating shaft (30) and the members fixed thereto are defined as rotating shaft side members (30, 51), and the housing (40) and the members fixed thereto are defined as housing side members (40, 52). Is defined on the rotary shaft side member (30, 51) and the housing side member (40, 52), and the annular lip seal (53) is disposed so as to be in contact with the other. When,
As the temperature rises, the lip seal (53) is deformed from a shape in contact with the other of the housing side member (40, 52) and the rotary shaft side member (30, 51) to a non-contact shape. (54).
The said lip seal (53) is arrange | positioned in the exterior side of the said housing (40) rather than the contact surface of the said rotating ring (51) and the said fixed ring (52). The shaft seal device described.
The lip seal (53) is fixed to one of the rotating ring (51) and the fixed ring (52) and arranged so as to be in contact with the other. The shaft seal device described.
The said lip seal (53) is extended | stretched on the diameter outer side of the said rotating shaft (30) rather than the contact surface of the said rotating ring (51) and the said fixed ring (52). 4. The shaft seal device according to any one of 3 to 3.
The lip seal (53) is made of rubber or resin,
The deformation part (54) is formed of bimetal,
The shaft seal device according to any one of claims 1 to 4, wherein the deformable portion (54) and the lip seal (53) are integrally formed by insert molding.
The lip seal (53) is made of rubber or resin,
The deformation part (54) is formed of bimetal,
The deformable portion (54) and the lip seal (53) are locked by locking portions (53b, 53c) formed on the outer surface of the lip seal (53). The shaft seal device according to any one of claims 1 to 4, wherein the shaft is integrally deformed.
The compressor (10) is applied to a vapor compression refrigeration cycle apparatus employing carbon dioxide as a refrigerant,
The shaft seal device according to any one of claims 1 to 8, wherein the compression target fluid is the carbon dioxide.