JP4263281B2 - Scroll compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a scroll compressor used for refrigeration and air conditioning, and more particularly, to a mounting structure for a movable spiral winding prevention mechanism.
[0002]
[Prior art]
Several proposals have been made for a movable spiral rotation prevention mechanism used in a scroll compressor. As one of them, a plurality of ball rolling grooves are formed in the circumferential direction on the surface of a ring plate-like single plate, and the back surface is fitted with a race support member and a pin hole of the race support member. There is a ball coupling including a pin for fixing a race and a plurality of balls that roll in a plurality of ball rolling grooves (see, for example, JP-A-5-33811).
[0003]
With reference to FIG. 6, a conventional scroll compressor having this type of ball coupling will be described.
[0004]
This scroll compressor is used for refrigerating and air-conditioning, and has a casing 3 including a cup-shaped portion 1 and a front housing 2 with its open end closed. A fixed scroll member 4 and a movable scroll member 5 are arranged inside the cup-shaped portion 1. The fixed scroll member 4 is fixed to the cup-shaped portion 1 and forms a discharge chamber 6 in cooperation with the cup-shaped portion 1 on the back surface thereof. The movable scroll member 5 performs a circular orbital motion without rotating with a predetermined radius in a state where the movable spiral member 5a is engaged with the fixed spiral member 4a of the fixed scroll member 4, thereby obtaining a known gas compression action. Then, the compressed gas is discharged into the discharge chamber 6. In addition, rotation prevention of the movable scroll member 5 is performed by the movable spiral winding prevention mechanism 7 described in detail later.
[0005]
The front housing 2 has a cylindrical portion 11. A main shaft 12 is inserted inside the cylindrical portion 11 and is rotatably supported by the front housing 2 by bearings 13 and 14. An eccentric shaft 15 is provided at one end of the main shaft 12 in the front housing 2. The eccentric shaft 15 is engaged with the movable scroll member 5 via an eccentric bush 16. In this way, the movable scroll member 5 is driven so as to move in a circular orbit as the main shaft 12 rotates.
[0006]
A rotor 22 is rotatably supported via a bearing 21 on the outside of the cylindrical portion 11 of the front housing 2. The rotor 22 is rotationally driven by an automobile engine or the like via a belt. As is known, the rotational power of the rotor 22 is applied to and removed from the main shaft 12 by an electromagnetic clutch 23.
[0007]
Next, the movable spiral winding prevention mechanism 7 will be described.
[0008]
This movable spiral rotation prevention mechanism 7 is called a ball coupling, and is a first race 31 fixed to the movable scroll member 5 with a pin 24 and a first race fixed to the front housing 2 with a pin 25. A second race 32 that is axially opposed to 31, and a plurality (at least three) of balls that are interposed between the first and second races 31 and 32 and prevent the rotation of the first race 31. 33. Here, each of the front housing 2 and the movable scroll member 5 is made by cutting after producing the original shape by casting, and functions as a race support member.
[0009]
As shown in FIG. 7, the first race 31 is formed of a ring-shaped single plate and has a plurality of (at least three) ball rolling grooves 34 along which the balls 33 roll along the circumferential direction. At regular intervals. A pin hole 36 for inserting the pin 24 is formed inside the inscribed circle of the plurality of ball transfer grooves 34. On the other hand, the pinhole 37 is also formed in the movable scroll member 5 as shown in FIG. The first race 31 is fixed by inserting the pin 24 together with the pin holes 36 and 37.
[0010]
As shown in FIG. 9, the second race 32 is also made of a ring-shaped single plate and has a plurality of (at least three) ball rolling grooves 38 along which the balls 33 roll along the circumferential direction. At regular intervals. A pin hole 41 for inserting the pin 25 is formed outside the circumscribed circle of the plurality of ball transfer grooves 38. On the other hand, a pin hole 42 is also formed in the front housing 2 as shown in FIG. The second race 32 is fixed by inserting the pin 25 together with these pin holes 41 and 42.
[0011]
[Problems to be solved by the invention]
However, in the conventional structure, since the outer diameter of the race fixed to the front housing is restricted by the position of the pin hole, it is difficult to reduce the diameter of the race, which is an obstacle to reducing the diameter of the compressor. Also, since the inner diameter of the race fixed to the movable scroll member is restricted by the position of the pin hole, it is difficult to increase the diameter. Therefore, a small-diameter bearing with a small allowable load must be used as a bearing for driving the movable scroll member. I didn't get it.
[0012]
Therefore, an object of the present invention is to provide a scroll compressor capable of reducing the diameter of the race on the side fixed to the front housing.
[0013]
Another object of the present invention is to provide a scroll compressor that can use a large-diameter bearing having a large allowable load as a bearing for the movable scroll member.
[0014]
Still another object of the present invention is to provide a scroll compressor capable of forming a race fixing portion without requiring special processing.
[0015]
[Means for Solving the Problems]
According to the present invention, a plurality of ball rolling grooves are formed in the circumferential direction on the surface of a single ring plate-like plate, and the back surface is supported by the race support member, and fitted into the pin holes of the race support member. In the scroll compressor having a movable spiral rotation prevention mechanism including a pin for fixing the race and a plurality of balls rolling in the plurality of ball rolling grooves, the pin hole of the race support member The peripheral portion is formed at a position avoiding interference with the back surfaces of the plurality of ball transfer grooves, and is higher than the plurality of groove back surface support portions that support the back surfaces of the plurality of ball rolling grooves, and the pin holes The scroll type compressor is characterized in that the peripheral portion of the is a fan-shaped stepped portion .
[0017]
The support member is a front housing of a compressor, and an inward surface of the stepped portion in a radial direction of the front housing has a diameter equal to or larger than a circumscribed circle of a contact portion of the front housing on the back surface of the plurality of ball transfer grooves. And the groove back surface support portion is a part of the material skin having a diameter larger than the diameter of the circumscribed circle of the convex portions on the back surface side of the plurality of ball transfer grooves. Preferably it is formed.
[0018]
Further, the support member is a movable scroll member of a compressor, and an outward surface of the stepped portion in a radial direction of the movable scroll member is inscribed with a contact portion of the movable scroll member on the back surface of the plurality of ball transfer grooves. The diameter is less than a circle and formed by cutting, and the groove back surface support portion is a diameter smaller than the diameter of the inscribed circle of the back side convex portions of the plurality of ball transfer grooves. It is preferable that it is made of material skin.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
A scroll compressor according to an embodiment of the present invention will be described with reference to FIGS. Parts similar to those of the scroll compressor shown in FIGS. 6 to 10 are denoted by the same reference numerals, and description thereof is omitted.
[0020]
First, referring to FIGS. 2 and 3 together with FIG. 1, a substantially fan-shaped step portion 51 is provided in the peripheral portion of the pin hole 37 of the movable scroll member 5 serving as a race support member. The step portion 51 is formed at a position that avoids interference with the back surfaces of the plurality of ball transfer grooves 34 of the first race 31, and also supports the back surfaces of the plurality of ball rolling grooves 34 (that is, the plurality of grooves). It is formed higher than the back support portion. In other words, when the peripheral portion of the pin hole 37 of the movable scroll member 5 supports the back surface of the ball transfer groove 34 of the first race 31, the ball of the first race 31 It is formed of a stepped portion 51 that is increased by an amount substantially equal to or less than the convex amount on the back surface of the transfer groove 34, and two back surfaces (radius Ra ′) of the ball transfer groove 34 of the first race 31. It is formed of a substantially fan-shaped step portion 51 that avoids the interference.
[0021]
Further, the outward surface 52a of the stepped portion 51 in the radial direction of the movable scroll member 5 has a diameter that is at most equal to the diameter of the inscribed circle of the plurality of groove back surface support portions, and is formed by cutting. The portion other than the step portion 51 and the portion that receives the inner peripheral portion of the first race 31 has an inner diameter smaller than the diameter of the inscribed circle of the plurality of ball transfer grooves 34 (that is, cutting after casting) The interference prevention groove | channel 52 which consists of the surface which does not perform etc. is formed. In other words, the ball transfer groove in which the outer diameter of the step portion 51 around the pin hole 37 provided in the movable scroll member 5 is arranged with a plurality of pitch circle radii Rb in the first race 31. 34 is formed by cutting with a radius (Rs2) equal to or less than the radius (Rb-Rc) of the inscribed circle of the contact portion (radius Rc) of the scroll member 5, and a step around the pin hole 37 Except for the portion 51, the first race 31 has a radius (Rs1) smaller than the radius (Rb-Ra ') of the inscribed circle of the back-side convex portion 53 of the ball transfer groove 34 in the plurality of ball transfer grooves 34, and is formed of material skin. . However, Ra ′> Rc, Rs1 <Rs2, Rs1 <Rb−Ra ′, and Rs2 ≦ Rb−Rc.
[0022]
Next, referring to FIGS. 4 and 5 together with FIG. 1, a substantially fan-shaped stepped portion 54 is provided in the periphery of the pin hole 42 of the front housing 2 serving as a race support member. The step portion 54 is formed at a position that avoids interference with the back surfaces of the plurality of ball transfer grooves 38 of the second race 32, and also supports the back surfaces of the plurality of ball rolling grooves 38 (that is, the plurality of grooves). It is formed higher than the back support portion. In other words, when the peripheral portion of the pin hole 42 of the front housing 2 supports the back surface of the ball transfer groove 38 of the second race 32, the ball transfer of the second race 32 is performed. It is formed by a stepped portion 54 that is higher by an amount substantially equal to or less than the convex amount on the back surface of the groove 38, and interferes with two back surfaces (radius Ra) of the ball transfer groove 38 of the second race 32. It is formed by a substantially fan-shaped stepped portion 54 that avoids the above.
[0023]
Further, the inward surface 54 a of the stepped portion 54 in the radial direction of the front housing 2 has a diameter that is at least the same as the diameter of the circumscribed circle of the plurality of groove back support portions, and is formed by cutting. In addition, the portion that receives the outer peripheral portion of the second race 32 is formed with an interference prevention groove 55 made of material skin having an outer diameter larger than the diameter of the circumscribed circle of the plurality of ball transfer grooves 38. In other words, the inner diameter of the stepped portion 54 around the pin hole 42 provided in the front housing 2 has a plurality of pitch circle radii Rb arranged in the first race 31. The rear surface has a radius (Rh2) equal to or greater than the radius (Rb + Rc) of the circumscribed circle of the contact portion (radius Rc) of the front housing 2 and is formed by cutting. It is formed of a raw material skin having a radius (Rh1) larger than the radius (Rb + Ra) of the circumscribed circle of the back side convex portion 56 of the plurality of ball transfer grooves 38 in the second race 32. However, Ra> Rc, Rh1> Rh2, Rh1> Ra + Rb, and Rh2 ≧ Rb + Rc.
[0024]
【The invention's effect】
As described above, according to the scroll compressor of the present invention, the race on the side fixed to the front housing can be reduced in diameter. Furthermore, a large-diameter bearing having a large allowable load can be used as a bearing for the movable scroll member. Further, it is possible to form the race fixing portion without requiring special processing.
[Brief description of the drawings]
FIG. 1 is a vertical cross-sectional view of a scroll compressor provided with a movable spiral rotation prevention mechanism according to an embodiment of the present invention.
2 is a perspective view of a first race in the scroll compressor of FIG. 1; FIG.
3 is a perspective view of a movable scroll member in the scroll compressor of FIG. 1. FIG.
4 is a perspective view of a second race in the scroll compressor of FIG. 1; FIG.
5 is a perspective view of a front housing in the scroll compressor of FIG. 1. FIG.
FIG. 6 is a longitudinal sectional view of a conventional scroll compressor.
7 is a front view of a first race in the scroll compressor of FIG. 6. FIG.
8 is a front view of a movable scroll member in the scroll compressor of FIG. 6. FIG.
9 is a front view of a second race in the scroll compressor of FIG. 6. FIG.
10 is a front view of a front housing in the scroll compressor of FIG. 6. FIG.
[Explanation of symbols]
2 Front housing 4 Fixed scroll member 5 Movable scroll member 7 Movable spiral rotation prevention mechanism 12 Main shaft 15 Eccentric shaft 16 Eccentric bush 22 Rotor 23 Electromagnetic clutch 24 Pin 25 Pin 31 First race 32 Second race 33 Ball 34 Ball rolling Running groove 36 Pin hole 37 Pin hole 38 Ball transfer groove 41 Pin hole 42 Pin hole 51 Step portion 52 Interference prevention groove 53 Back side convex portion 54 Step portion 55 Interference prevention groove 56 Back side convex portion

Claims (3)

A plurality of ball rolling grooves are formed in the circumferential direction on the surface of a single ring plate-like plate, the back surface is supported by a race support member, and the race is fixed by fitting into the pin hole of the race support member. And a scroll type compressor including a plurality of balls rolling through the plurality of ball rolling grooves, wherein the peripheral portion of the pin hole of the race support member includes the plurality of pins. Are formed higher than the plurality of groove back support portions supporting the back surfaces of the plurality of ball rolling grooves at a position avoiding interference with the back surface of the ball transfer grooves, and the peripheral portion of the pin hole is substantially fan-shaped. A scroll compressor characterized by being a step portion . The support member is a front housing of a compressor, and an inward surface of the stepped portion in the radial direction of the front housing has a diameter equal to or larger than a circumscribed circle of a contact portion of the front housing on the back surface of the plurality of ball transfer grooves. The groove back surface support portion, which is formed by cutting, is a portion having a diameter larger than the diameter of the circumscribed circle of the back side convex portions of the plurality of ball transfer grooves, and is formed of material skin. The scroll compressor according to claim 1 , wherein the scroll compressor is provided. The support member is a movable scroll member of a compressor, and an outward surface of the stepped portion in a radial direction of the movable scroll member is equal to or less than an inscribed circle of a contact portion of the movable scroll member on the back surface of the plurality of ball transfer grooves. The groove back surface support portion and the portion other than the stepped portion have a diameter smaller than the diameter of the inscribed circle of the back side convex portions of the plurality of ball transfer grooves. 2. The scroll compressor according to claim 1 , wherein the scroll compressor is formed of material skin.

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