WO2012005150A1

WO2012005150A1 - Scroll compressor

Info

Publication number: WO2012005150A1
Application number: PCT/JP2011/064885
Authority: WO
Inventors: 武井祐治
Original assignee: サンデン株式会社
Priority date: 2010-07-06
Filing date: 2011-06-29
Publication date: 2012-01-12
Also published as: US20130209305A1; EP2589808A1; JP2012017656A; CN102985696A

Abstract

A scroll compressor configured in such a manner that a back pressure chamber is formed on the back surface side of the movable spiral body using an annular seal means, and pressurized fluid is introduced into the back pressure chamber through a pressure introduction hole. A thrust bearing member which is a separate member from the seal means and which bears a thrust force acting toward the main bearing member from the bottom plate section side of the movable spiral body is disposed between the back surface of the bottom plate section of the movable spiral body and the front surface of the main bearing member which faces the back surface of the bottom plate section. The scroll compressor is configured in such a manner that the scroll compressor can satisfy the demand for more compactness and that a reduction in the durability and sealing function of the annular seal means can be minimized.

Description

Scroll compressor

The present invention relates to a scroll compressor, and more particularly, to an improvement in a back pressure mechanism provided on the back side of a movable spiral body constituting a scroll compression mechanism.

2. Description of the Related Art A scroll type compressor having a scroll type compression mechanism composed of a fixed spiral body and a movable spiral body that swirls with respect to the fixed spiral body is well known. In such a scroll compressor, a thrust load is generated in the movable spiral body due to the compression reaction force of the fluid being compressed, and due to this thrust load, the movable spiral body and the housing portion that supports the movable spiral body, etc. Although there is a possibility that wear or the like may occur, in order to suppress such wear or the like, a pressurized fluid is guided from the inside of the compression mechanism to the back side of the movable spiral body, and the above described with respect to the movable spiral body. It is known that it is effective to apply a back pressure in a direction opposite to the thrust load and reduce the thrust load that causes the wear and the like by the back pressure.

For example, Patent Document 1 discloses a back pressure chamber formed as a space between the back surface of the bottom plate portion of the movable spiral body and the surface of the main bearing member facing the back surface, and one of the back surface and the surface. At least one annular groove formed in the annular groove, an annular sealing means mounted in a movable state in the annular groove and in sliding contact with the other surface, a crankshaft for driving the movable spiral body, and the above It is formed on the back side of the bottom plate portion of the movable spiral body by sealing the gap with an annular shaft seal means mounted in a movable state in the gap with the main bearing member, and the seal means and the shaft seal means. Also disclosed is a scroll compressor having a pressure introducing hole for supplying a pressurized fluid to the back pressure chamber.

Japanese Patent No. 4262949

However, when the back pressure mechanism is to be configured on the back side of the bottom plate portion of the movable spiral body, the annular groove as described above and the annular sealing means attached to the groove are required. Since it is also necessary to provide a rotation preventing mechanism for the movable spiral body on the back side of the body, it may be difficult to fit the same diameter as a compressor without a back pressure mechanism. Further, in the structure described in Patent Document 1, since the annular groove and the annular sealing means for forming the back pressure chamber are arranged on the inner diameter side of the rotation preventing mechanism of the movable spiral body, These sealing means and the like that define the radial size are disposed at a relatively small diameter position, and the area for receiving the back pressure in the back pressure chamber is relatively small. In order to increase the pressure receiving area of the back pressure chamber with such a structure, it is necessary to increase the body diameter of the compressor itself, and it is difficult to make the entire compressor small. On the other hand, in order to obtain a desired force by back pressure without increasing the body diameter of the compressor, the pressure in the back pressure chamber must be increased. The fluid introduced from the compression mechanism into the pressure chamber is likely to leak, and when the leakage amount increases, the volume efficiency of the compressor is reduced. Furthermore, when the pressure in the back pressure chamber is increased, the durability and sealing function of the annular sealing means may be greatly deteriorated due to changes over time.

Accordingly, an object of the present invention is to focus on the above-mentioned problems, and to configure a desired back pressure mechanism without increasing the diameter of the compressor, and to reduce the pressure receiving area in the back pressure chamber. It is possible to keep the pressure in the back pressure chamber low by taking it large, which can satisfy the demand for downsizing of the compressor and reduce the amount of leakage from the seal part of the back pressure chamber. It is possible to improve the volumetric efficiency of the compressor, and by lowering the back pressure chamber, it is possible to suppress the deterioration of the annular sealing means and the sealing function due to changes over time, etc. It is an object of the present invention to provide a scroll compressor that can improve the lubrication of the blocking mechanism and improve the reliability.

In order to solve the above-mentioned problems, a scroll compressor according to the present invention has a scroll-type compression mechanism including a fixed spiral body and a movable spiral body that is swung with respect to the fixed spiral body, and is eccentric at one end. A shaft for driving the movable spiral body by the crank portion, a main bearing member for rotatably supporting the shaft via a main bearing, a back surface of the bottom plate portion of the movable spiral body, and the opposite surface A rotation-preventing mechanism provided between the main bearing member and the surface of the main bearing member opposed to the back surface of the bottom plate portion of the movable spiral body. A back pressure chamber formed as a space therebetween, at least one annular groove formed on one of the back surface of the bottom plate portion of the movable spiral body and the surface of the main bearing member, It is mounted in a movable state in the groove The annular sealing means that is in sliding contact with the other surface, the shaft sealing means that is mounted between the shaft and the main bearing member, and the sealing means and the shaft sealing means that are formed in a sealed space. In a scroll compressor having a pressure introduction hole for supplying a pressurized fluid to the back pressure chamber,
As a separate member from the sealing means between the back surface of the bottom plate portion of the movable spiral body and the surface of the main bearing member facing the movable spiral body, the bottom plate portion side of the movable spiral body is moved to the main bearing member side. The thrust receiving member which receives the thrust force of the above is interposed.

In such a scroll compressor according to the present invention, the thrust receiving member is provided separately from the annular sealing means that is mounted in the annular groove and seals to form the back pressure chamber. The annular sealing means that has been provided with both the sealing function and the function of receiving the thrust force in FIG. 5 may be mainly provided with only the sealing function, and the thrust receiving member may be provided with the function of receiving the thrust force. It becomes possible. In other words, the annular sealing means does not have a function of receiving a thrust force and can be specialized only for the sealing function. As a result, the degree of freedom in designing the annular sealing means is increased, and higher sealing performance and durability can be provided. Due to the high sealing performance and durability, the back pressure chamber can exert the desired back pressure function on the movable spiral body, that is, the desired thrust load reducing function and the function of pressing against the fixed spiral body, resulting from the thrust load. It is possible to improve the volumetric efficiency of the compressor, and consequently the coefficient of performance, by suppressing wear and the like.

In the scroll compressor according to the present invention, the thrust receiving member is interposed so that the bottom plate portion of the movable spiral body is in contact with the thrust receiving member when the compressor is started and is not in contact during steady operation. It is preferable that That is, at the time of start-up, the pressure in the back pressure chamber has not yet increased sufficiently, and a relatively large thrust load may act from the bottom plate portion side of the movable spiral body toward the surface side of the main bearing member. When the bottom plate portion of the body comes into contact with the thrust receiving member, the thrust receiving member reliably receives the thrust load, prevents an undesirable thrust load from being applied to the annular sealing means, wear due to the thrust load, etc. Thus, it is possible to provide the annular sealing means with higher sealing performance and durability. On the other hand, during steady operation, the back pressure chamber is sufficiently supplied with pressurized fluid and the pressure in the back pressure chamber is kept high enough to receive the thrust load. Since the thrust receiving member does not come into contact with the thrust receiving member, the durability and life of the thrust receiving member can be improved.

Also, in the scroll compressor according to the present invention, the thrust receiving member can take various forms. For example, the thrust receiving member is formed of a plate-like member extending annularly in the circumferential direction on the surface of the main bearing member, or the thrust receiving member is formed on the surface of the main bearing member and intermittent in the circumferential direction. It is possible to adopt a form comprising a plurality of arc-shaped members loosely fitted (movably mounted) in a plurality of arc-shaped grooves arranged in a regular manner. In any form, since the thrust receiving member is responsible for the thrust load, the thrust receiving member preferably has high wear resistance. For example, the thrust receiving member is preferably made of wear-resistant metal or resin.

Further, in addition to the improvement in sealing performance and durability by increasing the degree of freedom in designing the annular sealing means, the annular groove and the sealing means are arranged in a position including the rotation prevention mechanism in the radial direction. By adopting the above, it becomes possible to largely change the arrangement position of the annular sealing means to the outer side as compared with the position described in Patent Document 1 described above. Accordingly, the radial dimension of the back pressure chamber is increased, and accordingly, the pressure receiving area (pressure receiving area) in the back pressure chamber can be increased. That is, the pressure receiving area in the back pressure chamber can be increased without increasing the body diameter of the compressor. Accordingly, it is possible to satisfy the demand for downsizing of the compressor, and it is possible to reduce the amount of leakage from the seal portion of the back pressure chamber by reducing the pressure in the back pressure chamber, resulting in the compressor. It is possible to improve the volumetric efficiency of. Moreover, since the load condition on the annular sealing means can be reduced by reducing the pressure in the back pressure chamber, it becomes possible to suppress the durability of the annular sealing means and the deterioration of the sealing function due to changes over time. Further, it becomes possible to further improve the sealing performance and durability. Further, since the rotation preventing mechanism part of the movable spiral body is substantially included in the back pressure chamber, the rotation preventing mechanism for the pressurized fluid containing lubricating oil introduced from the compression mechanism into the back pressure chamber through the pressure introducing hole. It can be effectively used for lubricating parts, and the durability and reliability can be improved.

Thus, in the present invention, a back pressure chamber having a desired pressure receiving area that requires a low pressure without increasing the cylinder diameter of the compressor can be configured, and the excellent sealing performance, durability, and reliability of the back pressure mechanism can be achieved. Since the present invention can be realized, the present invention is particularly suitable for a compressor for a vehicle air conditioner that is strongly demanded for downsizing and improved durability.

According to the scroll compressor according to the present invention, a back pressure chamber excellent in sealing performance, durability, reliability, and the like can be formed, and therefore, high volume efficiency and high compared with a compressor having no back pressure mechanism. Achieve a coefficient of performance. In addition, the cylinder diameter is the same as that of a compressor that does not have a back pressure mechanism without increasing the cylinder diameter of the compressor, and it is excellent in sealing performance and durability. Since the back pressure chamber can be configured, a small and highly efficient scroll compressor can be provided.

1 is a longitudinal sectional view of a scroll compressor according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of the scroll compressor which concerns on the 2nd embodiment of this invention. It is a principal part expanded sectional view of a 1st embodiment. It is a principal part expanded sectional view of a 2nd embodiment. It is a top view of the main bearing member in which the thrust receiving member in the 1st embodiment was provided. It is a top view of the main bearing member in which the thrust receiving member in the 2nd embodiment was provided. It is a top view which shows the back surface of the baseplate part of the movable spiral body in this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a scroll compressor 100 according to a first embodiment of the present invention, and FIG. 2 shows a scroll compressor 200 according to a second embodiment of the present invention, both of which have a built-in motor. It is comprised by the made electric compressor. These

scroll compressors

100 and 200 are used as, for example, a compressor for a vehicle air conditioner, and are used for compressing a refrigerant or the like. Since the first embodiment and the second embodiment are different only in the thrust receiving member portion and the other portions have substantially the same configuration, the same configuration with reference to FIGS. 1 and 2 at the same time. The parts will be described using the same reference numerals, and only the thrust receiving member parts will be described using different reference numerals.

In FIG. 1 and FIG. 2, the

scroll compressors

100 and 200 have a scroll type compression mechanism 3 including a fixed spiral body 1 and a movable spiral body 2 that pivots relative to the fixed spiral body 1. The fluid (for example, refrigerant) taken into the fluid pocket 4 is compressed as the fluid pocket 4 formed in the scroll compression mechanism 3 moves toward the center. The compressed fluid is discharged from a discharge hole 5 provided at the center of the fixed spiral body 1 into a discharge chamber 7 formed in the rear plate 6, and the contained lubricating oil is separated by a separation pipe 8. From the discharge port section 9, it is sent to an external circuit (not shown).

In the present embodiment, the fixed spiral body 1 is fixedly installed inside one end of the stator housing 10, and the rear plate 6 is fixed to the end surface of the stator housing 10 via bolts or the like. A motor 12 that rotationally drives the shaft 11 for driving the movable spiral body 2 is built in the other end side of the stator housing 10. The motor 12 includes a stator 13 fixed in the stator housing 10 and a rotor 14 rotated with respect to the stator 13, and the shaft 11 is rotated integrally with the rotor 14. The shaft 11 is rotatably supported by a front bearing 17 that is mounted on an inverter case 16 that houses the inverter portion 15, and a main bearing 19 that is mounted on a main bearing member 18 that is fixed in the stator housing 10. . A crank portion 20 (crank pin) is formed at one end of the shaft 11 at a position eccentric from the axis of the shaft 11. The crank portion 20 is rotatably inserted into an eccentric bush 22 that is rotatably supported on the back side of the movable spiral body 2 via a drive bearing 21, and the crank portion 20 is eccentric as the shaft 11 rotates. Via the bush 22 and the drive bearing 21, the movable spiral body 2 is swung in a state where rotation is prevented. A counterweight 23 is formed integrally with the eccentric bush 22. The rotation preventing mechanism 24 of the movable spiral body 2 includes a rotation prevention ring 26 mounted in a hole 25 formed on the back surface of the movable spiral body 2 and a rotation protruding from the main bearing member 18 into the rotation prevention ring 26. The rotation prevention mechanism 24 including the ring 26 and the pin 27 is arranged in a plurality in the circumferential direction.

A back pressure chamber 28 is formed as a space between the back surface of the bottom plate portion 2a of the movable spiral body 2 and the surface of the main bearing member 18 facing the bottom plate portion 2a. The back pressure chamber 28 has at least one annular groove 29 formed on the back surface of the bottom plate portion 2 a of the movable spiral body 2 and an annular ring that is mounted in the groove 29 and is in sliding contact with the surface of the main bearing member 18. And a seal portion having a shaft seal 31 mounted between the outer peripheral surface of the shaft 11 and the inner peripheral surface of the main bearing member 18 at the side of the main bearing 19. And is formed in a sealed space. A fluid pressurized from within the compression mechanism 3 is supplied to the back pressure chamber 28 through a pressure introducing hole 32 provided in the bottom plate portion 2 a of the movable spiral body 2. By introducing the pressurized fluid into the back pressure chamber 28, a thrust load (force for pressing the movable spiral body 2 against the main bearing member 18) acting on the movable spiral body 2 due to the compression reaction force is reduced. Alternatively, the pressure in the back pressure chamber 28 acts on the movable spiral body 2 so as to press the movable spiral body 2 against the fixed spiral body 1 side. In this embodiment, the fluid pressurized in the compression mechanism 3 is supplied from the compression mechanism 3 into the back pressure chamber 28 through the pressure introduction hole 32. For example, it is also possible to supply the gas into the back pressure chamber 28 from a discharge chamber or an oil separation chamber of the compressor.

A seal portion including an annular groove 29 and an annular seal 30 for forming the back pressure chamber 28 in a sealed space is provided at a position including the rotation prevention mechanism 24 in the radial direction. A large pressure receiving area on the bottom plate 2a side of the movable spiral body 2 is secured. By such an increase in the pressure receiving area in the back pressure chamber 28, the pressure in the back pressure chamber 28 can be reduced, the degree of freedom in designing the annular seal 30 is increased, and the sealing performance of the annular seal 30 is increased. Durability can be improved. Further, the arrangement as described above makes it possible to increase the pressure receiving area in the back pressure chamber 28 without increasing the diameter of the compressor, and a back pressure mechanism is provided while ensuring high sealing performance and durability. Therefore, it is possible to avoid an increase in the size of the compressor and to reduce the size of the compressor.

And as a member different from the annular seal 30 between the back surface of the bottom plate portion 2a of the movable spiral body 2 and the surface of the main bearing member 18 opposed thereto, at a position closer to the inner diameter side than the annular seal 30, Thrust receiving members 33 (form of FIG. 1) and 34 (form of FIG. 2) that receive a thrust force from the bottom plate portion 2a side of the movable spiral body 2 to the main bearing member 18 side are interposed while being movable in the axial direction. Has been. By providing the

thrust receiving members

33 and 34 in this way, the thrust force from the movable spiral body 2 side to the main bearing member 18 side is exclusively received by the

thrust receiving members

33 and 34, and the annular seal 30 is subjected to the thrust force. It is possible to specialize only in the sealing function without having the function of receiving. As a result, the sealing performance and durability of the annular seal 30 can be greatly improved. In other words, the annular seal 30 does not have to be subjected to thrust force, and only the sealing performance needs to be taken into account. Therefore, the degree of freedom in designing the annular seal 30 is greatly increased, and appropriate material selection and design are possible. By doing so, the sealing performance and durability of the annular seal 30 can be greatly improved. Further, in addition to the low pressure of the back pressure chamber 28 due to the increase in the pressure receiving area in the back pressure chamber 28 described above, the back pressure chamber from the annular seal 30 portion is greatly improved by greatly improving the sealing performance and durability of the annular seal 30. The amount of leakage of the fluid introduced into the valve 28 can be greatly reduced, thereby making it possible to improve the volume efficiency of the compressor and improve the coefficient of performance. In particular, as described above, the

thrust receiving members

33 and 34 may contact the

thrust receiving members

33 and 34 with the bottom plate portion 2a of the movable spiral body 2 when the compressor is started, and become substantially non-contact during steady operation. By providing it as possible, the durability of both the annular seal 30 and the

thrust receiving members

33 and 34 can be improved.

The above-described excellent effects are achieved by function separation in which the annular seal 30 has only a sealing function and the

thrust receiving members

33 and 34 have only a function of handling a thrust load. This functional separation is achieved by providing the

thrust receiving members

33 and 34 as members different from the annular seal 30.

More specifically, the

thrust receiving members

33 and 34 will be described. The first embodiment shown in FIG. 1 can be configured as shown in FIGS. 3 and 5, and the second embodiment shown in FIG. Can be configured as shown in FIGS. That is, in the first embodiment, as shown in FIG. 3, a shallow annular step 41 is formed on the surface of the main bearing member 18 facing the movable spiral body 2, and the step 41 is compared with the step 41. An annular thrust receiving member 33 formed of a thin plate material is disposed, and the thrust receiving member 33 is supported so as to be sandwiched between the stepped portion 41 and the back surface of the bottom plate portion 2a of the movable spiral body 2. You can do it. In this case, in order to avoid interference between the rotation preventing pin 27 protruding from the surface of the main bearing member 18 and the thrust receiving member 33, the rotation preventing pin 27 can penetrate the thrust receiving member 33 as shown in FIG. The hole 42 may be opened. Further, as shown in FIG. 5, the radially outer surface of the thrust receiving member 33 on the surface of the main bearing member 18 serves as a seal surface 43 on which the annular seal 30 swung together with the movable spiral body 2 is slidably contacted. It can be secured widely. As the relatively thin plate material constituting the thrust receiving member 33, for example, a wear-resistant metal plate made of SK material or the like is preferable. With such a metal plate, a desired surface roughness can be easily obtained. .

In the second embodiment, as shown in FIGS. 4 and 6, a plurality of grooves 51 extending in an arc shape in the circumferential direction are intermittently formed on the surface of the main bearing member 18 facing the movable spiral body 2. An arc-shaped thrust member 34 is mounted in each groove 51 in a loosely fitted state. The arc-shaped groove 51 and the arc-shaped thrust member 34 are disposed so as to avoid the position of the rotation prevention pin 27, and as shown in FIG. 6, radially outside the positions where the grooves 51 and the thrust member 34 are disposed. The surface of the main bearing member 18 is widely secured as a seal surface 52 on which the annular seal 30 swung together with the movable spiral body 2 is slidably contacted. As the material of the arc-shaped member that constitutes the thrust receiving member 34, for example, a highly wear-resistant resin (particularly engineering plastic) made of polyphenylene sulfide or the like is preferable. It is possible to obtain desirable sliding characteristics.

On the other hand, as shown in FIG. 7, for example, the structure on the back surface 61 side of the bottom plate 2a of the movable spiral body 2 is formed with a hole 62 for the drive bearing 21 at the center, and a hole 25 for the rotation prevention ring on the outer side. And a rotation prevention ring 26 is attached to the hole 25. An annular groove 29 is formed so as to contain a plurality of rotation prevention rings 26 (rotation prevention mechanisms), and the above-described annular seal 30 is attached to the groove 29.

The structure of the scroll compressor according to the present invention can be applied to any scroll compressor, and is particularly suitable for a compressor for a vehicle air conditioner that is strongly required to be downsized and improved in durability.

DESCRIPTION OF SYMBOLS 1 Fixed spiral body 2 Movable spiral body 2a Bottom plate part 3 of movable spiral body 3 Scroll type compression mechanism 4 Fluid pocket 5 Discharge hole 6 Rear plate 7 Discharge chamber 8 Separation pipe 9 Discharge port part 10 Stator housing 11 Shaft 12 Motor 13 Stator 14 Rotor DESCRIPTION OF SYMBOLS 15 Inverter part 16 Inverter case 17 Front bearing 18 Main bearing member 19 Main bearing 20 Crank part 21 Drive bearing 22 Eccentric bush 23 Counterweight 24 Rotation prevention mechanism 25 Hole 26 Rotation prevention ring 27 Rotation prevention pin 28 Back pressure chamber 29 Annular groove 30 annular seal 31 shaft seal 32

pressure introducing holes

33, 34 thrust receiving member 41 stepped portion 42 hole 43 annular seal seal surface 51 arc-shaped groove 52 annular seal seal surface 61 bottom plate back surface 62

drive bearing hole

100, 200 scroll type Compressor

Claims

A shaft that has a scroll-type compression mechanism including a fixed spiral body and a movable spiral body that is swiveled with respect to the fixed spiral body, has a crank portion that is eccentric at one end, and drives the movable spiral body by the crank portion And a main bearing member that rotatably supports the shaft via a main bearing, and a movable spiral body provided between a back surface of a bottom plate portion of the movable spiral body and a surface of the main bearing member facing the main plate. A rotation preventing mechanism that prevents rotation of the rotating spiral body, a back pressure chamber formed as a space between the back surface of the bottom plate portion of the movable spiral body and the surface of the main bearing member facing it, and the bottom plate of the movable spiral body At least one annular groove formed on any one of the rear surface of the portion and the surface of the main bearing member, and is movably mounted in the annular groove and is in sliding contact with the other surface. Annular sealing means, the shaft and the front A shaft sealing means mounted between the main bearing member and a pressure introducing hole for supplying a pressurized fluid to the back pressure chamber formed in a sealed space by the sealing means and the shaft sealing means. In the scroll type compressor
As a separate member from the sealing means between the back surface of the bottom plate portion of the movable spiral body and the surface of the main bearing member facing the movable spiral body, the bottom plate portion side of the movable spiral body is moved to the main bearing member side. A scroll compressor characterized by interposing a thrust receiving member for receiving the thrust force of.
2. The scroll type according to claim 1, wherein the thrust receiving member is interposed such that a bottom plate portion of the movable spiral body is in contact with the thrust receiving member when the compressor is started and is not in contact during steady operation. Compressor.
The scroll compressor according to claim 1 or 2, wherein the thrust receiving member is a plate-like member extending annularly in the circumferential direction on the surface of the main bearing member.
The thrust receiving member is composed of a plurality of arc-shaped members loosely fitted in a plurality of arc-shaped grooves formed on the surface of the main bearing member and intermittently arranged in the circumferential direction. The scroll compressor described in 1.
The scroll compressor according to any one of claims 1 to 4, wherein the thrust receiving member is made of a wear-resistant metal or resin.
The scroll compressor according to any one of claims 1 to 5, wherein the annular groove and the sealing means are arranged at a position including the rotation prevention mechanism in a radial direction.
The scroll compressor according to any one of claims 1 to 6, which is a compressor for a vehicle air conditioner.