JPH05141412A - Thrust support device for revolving member - Google Patents

Abstract

PURPOSE:To improve operation efficiency and life, and facilitate manufacture of a thrust support device which unautorotatably supports a revolving scroll member of a scroll compressor or the like. CONSTITUTION:An eccentric double row roller bearing 8 which prevents autorotation and supports a thrust load between a revolving scroll member 2 which performs eccentric rotation and a fixed member 8. At least three pair of roller bearings 8 are arranged around a rotational center O of the revolving scroll member 2. The paired roller bearings 8 are each formed by providing roller bearings 15, 16 which respectively support a thrust load on both side shaft parts of an eccentric shaft 14, being eccentric to each other. An angular boil bearing or a tapered roller bearing is used for the roller bearings 15, 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thrust support device used in a scroll compressor or the like to support a revolving member such as a revolving scroll member so as not to rotate.

[0002]

2. Description of the Related Art A scroll compressor, as shown in FIG. 4, has an orbiting scroll member 51 and a fixed scroll member 52.
Spiral partition walls 53 and 54 are respectively provided on the
The compression chamber 55 formed between
The compression operation is performed by changing the volume with the eccentric rotation. The orbiting scroll member 51 is eccentrically rotated by the orbiting radius of the eccentricity e by the rotation of the rotary drive shaft 57 by engaging the eccentric hole of the rotary drive shaft 57 with the shaft portion 51a protruding from the lower surface. The rotary drive shaft 57 is composed of a rotor shaft of a motor 58, and has upper and lower bearings 59, 6 on a fixed member 61.
Supported by 0.

The orbiting scroll member 51 is supported by a fixed member 61 by a thrust bearing 62 because a large thrust load is applied by the gas pressure in the compression chamber 55. Since the thrust bearing 62 does not have a general-purpose rolling bearing capable of supporting eccentric rotation, a slide bearing is generally used. Further, since the orbiting scroll member 51 needs to prevent rotation and be eccentrically rotated in a fixed posture, an appropriate rotation preventing device (not shown) is provided between the orbiting scroll member 51 and the fixed member 61. ..

However, in the above structure, since the thrust bearing 62 made of a slide bearing is used to support the orbiting scroll member 51, there is a problem that the coefficient of friction is large and the operating efficiency is lowered.

For this reason, attempts have been made to achieve rolling contact, and as one example, recesses 63 and 64 are formed in the orbiting scroll member 51 and the fixing member 62 as shown in FIG. 5 (A).
It is proposed that a ball be provided and a ball 65 be interposed. The recesses 63 and 64 are formed at a plurality of positions in the circumferential direction.
The diameters of the recesses 63 and 64 are designed such that the orbit diameter within which the ball 65 can roll is designed to be equal to the eccentricity e (FIG. 4) of the orbiting scroll member 51, and thus the movement range of the ball 65 is restricted. Thus, the rotation of the orbiting scroll member 51 is also prevented.

Instead of the recessed portion 63, it has been proposed that, as shown in FIG. 5 (B), raceway grooves 66 and 67 having an arc-shaped groove cross section are provided in an annular shape with the diameter of the eccentricity e (for example,). , JP-A-55-155916).

[0007]

In the structure of FIG. 5A, since the bottom surfaces of the recesses 63 and 64 are flat surfaces, the contact between the ball 65 and the bottom surfaces of the recesses 63 and 64 is point contact.
Therefore, when a large thrust load is applied by the gas pressure of the compression chamber 55 (FIG. 3) as described above, the contact pressure per unit area becomes very large, and wear and rolling fatigue are remarkable,
There is a problem that the life of the bearing is shortened.

In the case of the example of FIG. 5B, the raceway grooves 66, 6
Since the inner surface of 7 is arcuate, the contact area with the ball 65 is increased, the surface pressure is reduced, and the bearing life is improved. However, such an annular raceway groove 6 having an arcuate cross section
6, 67 to orbiting scroll member 51 and fixed frame 61
However, there is a problem that productivity is poor.

An object of the present invention is to improve the operating efficiency and life of a thrust support device for preventing rotation of a turning member to support eccentric rotation and to facilitate manufacture.

[0010]

In the thrust support device of the present invention, at least three pairs of rolling bearings are provided around the center of rotation between a rotating member and a fixed member which rotate eccentrically with each other. Each pair of rolling bearings is provided with rolling bearings capable of supporting a thrust load on shaft portions on both sides of the eccentric shaft that are eccentric to each other.

[0011]

According to this structure, the thrust load acting on the swiveling member is supported by rolling contact through the eccentric shaft and the rolling bearings on both sides of the pair of rolling bearings interposed between the swiveling member and the fixed member. To be done. Movement of the swivel member is restricted by the eccentric shafts of the pair of rolling bearings, but each eccentric shaft is eccentrically rotatable, and rotates eccentrically with the eccentric rotation of the swivel member. Therefore, the turning member is prevented from rotating due to eccentric rotation, and rotates eccentrically while maintaining a fixed posture.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. This embodiment is an example applied to a scroll compressor. The fixed scroll member 1 and the orbiting scroll member 2 each have spiral partition walls 3 and 4, and a compression chamber 5 is formed between the partition walls 3 and 4. The fixed scroll member 1 is fixed to a fixed member 6 serving as a housing, and the orbiting scroll member 2 is a pair of rolling bearings 8 described later.
It is supported by the fixing member 6.

In the orbiting scroll member 2, a transmitted shaft 2a protruding from the center of the lower surface is engaged with an eccentric hole 9 of the rotary drive shaft 7 via a radial bearing 10 such as a needle bearing, so that the rotary drive shaft 7 is rotated. Eccentric rotation is performed with a turning radius of the eccentricity amount a. The rotary drive shaft 7 is a rotor shaft of a motor 11, and is rotatably supported by the fixed member 6 by upper and lower bearings 12 and 13.

As shown in an enlarged view in FIG. 2, the pair of rolling bearings 8 has shaft portions 1 on both sides of the eccentric shaft 14 which are eccentric to each other.
Angular ball bearings 15 and 16 which are rolling bearings capable of supporting a thrust load are provided on 4a and 14b, respectively. Each of the angular ball bearings 15 and 16 has an outer ring fixed to the orbiting scroll member 2 and the fixed member 6, and an inner ring fixed to the eccentric shaft 14. The eccentric shaft 14 has a collar portion 14c in the middle, and the inner rings of the angular ball bearings 15 and 16 on both sides are engaged with each other. The eccentric amount b of the eccentric shaft 14 is set equal to the eccentric amount a which is the orbiting radius of the orbiting scroll member 2. The pair of rolling bearings 8 of this configuration have three or more pairs, for example, three pairs, around the rotation center O of the orbiting scroll member 2.
~ 8 pairs are evenly distributed.

The operation of the above configuration will be described. The orbiting scroll member 2 performs eccentric rotation with an orbiting radius a by the rotation of the rotary drive shaft 7. At this time, since the orbiting scroll member 2 is connected to the fixed member 6 by the plurality of pairs of rolling bearings 8, rotation due to eccentric rotation is prevented. That is, each 1
The eccentric shaft 14 of the pair of rolling bearings 8 is eccentrically rotated by the eccentric rotation of the orbiting scroll member 2 with an eccentric amount b equal to the radius a of the eccentric rotation. Therefore, the orbiting scroll member 2 rotates eccentrically while maintaining a constant angular relationship with the fixed member 6 without causing rotation. By such an eccentric rotation operation, the compression operation of the scroll compressor is performed.

The orbiting scroll member 2 is driven by the compressed gas pressure.
A large thrust load acts on the bearing, but this thrust load is supported by a pair of rolling bearings 8 in each part by rolling contact. In this case, the thrust load is supported by the fixing member 6 from the outer ring of the upper angular ball bearing 15 through the eccentric shaft 14 and the outer ring of the lower angular ball bearing 16.

This thrust support device can support the thrust load of the orbiting scroll member 2 which is eccentrically rotated in this manner by rolling contact while preventing rotation. By supporting the rolling contact in this manner, high operating efficiency can be obtained. The pair of rolling bearings 8 is composed of an eccentric shaft 14 and ordinary angular contact ball bearings 15 and 16, and various types of angular contact ball bearings having excellent durability have been commercialized and can be freely selected. Therefore, the life of the thrust support device can be easily improved. Further, since the pair of rolling bearings 8 which are manufactured as independent parts are incorporated, it is not necessary to process the raceway groove of the rolling element in the orbiting scroll member 2 or the fixed member 6, and the manufacturing can be easily performed. ..

In the above embodiment, the pair of rolling bearings 8
The angular ball bearings 15 and 16 are used for the eccentric shaft 14
Any bearing can be used as long as it can support a thrust load. For example, as shown in FIG.
8 may be used.

[0019]

According to the thrust support device of the present invention, the parts constituted by the eccentric shaft and the pair of rolling bearings for supporting the thrust load are arranged side by side around the rotation center of the turning member. Rotation due to eccentric rotation of the member can be prevented, and the thrust load of the turning member can be supported by rolling contact to improve the operating efficiency. As each rolling bearing, a normal bearing for thrust support can be used, so that the life of the thrust support device can be easily improved. Further, since a pair of rolling bearings manufactured as independent parts is incorporated, it is not necessary to process the raceway groove of the rolling element on the turning member or the like, and the manufacturing can be easily performed.

[Brief description of drawings]

FIG. 1 is a sectional view of a scroll compressor to which a thrust support device according to an embodiment of the present invention is applied.

FIG. 2 is an enlarged cross-sectional view of the pair of rolling bearings.

FIG. 3 is a sectional view of a pair of rolling bearings according to another embodiment.

FIG. 4 is a schematic sectional view of a conventional scroll compressor.

FIG. 5 is a partial cross-sectional view of a thrust support device of a scroll compressor in another conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fixed scroll member, 2 ... Orbiting scroll member, 6
... fixed member, 7 ... rotary drive shaft, 8 ... one pair of rolling bearings,
14 ... Eccentric shaft, 15, 16 ... Angular ball bearings, 17,
18 ... Tapered roller bearing

Claims (1)

[Claims] 1. At least three pairs of rolling bearings are provided around a center of rotation between a swivel member and a fixed member that rotate eccentrically with each other, and each pair of rolling bearings has eccentric shafts on opposite sides. A thrust support device for a revolving member, wherein each shaft portion is provided with a rolling bearing capable of supporting a thrust load.