JPH088309Y2 - Compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a compressor in which a piston reciprocates by a cam member.

[Conventional technology]

As shown in FIG. 5, the compressor using the cam member supports the drive shaft 2 on the front side and the rear side of the cylinder block 6, and the cam member 5 is integrally attached to substantially the center of the drive shaft 2. The cam member 5 has, for example, a cam plate portion 5'having a sinusoidal cam surface on its outer periphery, and causes the piston 3 to reciprocate in the bore 6a according to the curved displacement of the cam plate portion 5'by the rotation of the drive shaft 2. It is like this. That is, the piston 3 has spherical seats 3a, 3a formed to face each other so as to straddle the cam plate portion 5'of the cam member 5, and the balls 4, 4 are mounted on these spherical seats 3a, 3a.
4 is seated, while the other surface is fitted in arcuate grooves 5a formed around the cam plate 5 '. As a result, the rotation of the cam member 5 accompanying the rotation of the drive shaft 2 causes the balls 4 to move.
Rolls on the circular arc groove 5a to cause the movement of the piston 3 according to the cam surface of the cam plate portion 5 '. The front side of the cylinder block 6 is closed by the first housing 7, and the rear side is closed by the second housing 8. The first and second housings 7 and 8 are respectively formed with an intake chamber 9 and a discharge chamber 10 which communicate with the bore 6a at a predetermined timing.

In the compressor as described above, the arcuate grooves 5a, 5a formed in the cam member 5 are in linear contact with the balls 4 and wear due to rolling of the balls 4 is reduced. If the ball 4 is configured to directly contact the wave cam surface of the cam member without forming the arcuate groove 5a in the cam member 5, the cam surface will be greatly worn at the sliding contact position, which is not suitable for practical use. I don't get it.

[Problems to be solved by the device]

By the way, in the compressor shown in FIG. 5, the balls 4 are fitted in the spherical seat 3a on the piston side and the arc groove 5a on the cam side. When the distance to the center of the bore changes,
The relative position between the circular arc groove 5a and the piston 3 changes, and as shown in FIG. 6, the ball 4 moves in the circular arc groove 5a and the spherical seat 3a, respectively.
Therefore, there is a problem in that the circular arc groove 5a and the spherical seat 3a are unevenly worn and the durability is remarkably accelerated. In FIG. 6, the center of the bore changes in the radial outward direction around the drive shaft 2.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a compressor in which a ball is always aligned with a cam-side circular arc groove to prevent uneven wear.

[Means for solving the problem]

The present invention provides a ball which is rolled along the arc groove between a cam member having a cam plate portion having an arc groove in the circumferential direction of rotation of a drive shaft and a piston reciprocated by the cam member. A shoe that is fitted and further receives the other surface of the ball opposite to the arc groove is swingably provided on the seat surface of the piston.

[Action]

According to the present invention, the shoe provided between the piston and the ball finely moves on the bearing surface of the piston around the drive shaft while the ball is fitted in the arc groove on the cam side, and does not regulate the ball position from the piston side. I am trying. Therefore, the rolling position of the ball is restricted only in the cam side arcuate groove, and uneven wear does not occur between the ball and the arcuate groove.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

FIG. 1 is a sectional view showing an embodiment of a compressor according to the present invention. FIG. 2 is an enlarged sectional view of the ball fitting insertion portion shown in FIG. In these figures, the elements common to those in the configuration of FIG. 5 are designated by the same reference numerals.

In FIG. 1, as in FIG. 5, the cam member 5 has circular arc grooves on the front side and the rear side of each of the cam plate portions 5 ′.
5a, 5a are formed, and balls 4, 4 are formed in these arc grooves 5a, 5a.
Are fitted. The compressor 1 of this embodiment does not receive the balls 4 and 4 by directly mounting the spherical seat 3a (see FIG. 5) on the piston 3 and does not receive the shoes 11, 11 having the spherical seat 11a.
Is being received through.

More specifically, as shown in FIG. 2, the piston 3 is provided with ball fitting and inserting portions 12 and 12 facing the front and rear cam surfaces of the cam member 5, respectively. A guide hole 12a is formed in each of the portions 12 and 12 so that the shoe 11 can be finely moved in the radial direction around the drive shaft 2. Shoe 11
Has a projecting bottom portion 11b projecting in a flat shape on the side opposite to the spherical seat 11a, and the flat bottom surface 11c thereof comes into contact with the flat seat surface 12b which is the bottom surface of the guide hole 12a. These flat bottoms 11c
The flat seating surface 12b and the flat seating surface 12b are each smoothed.

In the compressor 1 having such a structure, the piston 3 reciprocates by the cam member 5 rotating with the drive shaft 2, and the suction chamber 9 and the cylinder chamber 6a communicate with each other.
The discharge process in which 10 and the cylinder chamber 6a communicate with each other is repeated to perform the operation as a compressor.

Then, when the position of the bore 6a changes in the R direction (radial direction with the drive shaft 2 as the center) in FIG. 2 due to machining variations in the cylinder block 6 and the cam member 5, the shoe 11
The sliding movement of the flat bottom surface 11c and the flat seat surface 12b of the guide hole 12a allows the shoe 11 to freely move in the R direction, and the position of the ball 4 is not restricted by the position of the piston 3. As a result, the ball 4 rolls without coming off from the cam side arcuate groove 5a, and uneven wear between the ball 4 and the arcuate groove 5a does not occur.

 Next, another embodiment will be described.

 FIG. 3 is a block diagram showing another embodiment of the present invention.

In this embodiment, the shoe 11 having the spherical seat 11a is formed in a semi-cylindrical shape, and the spherical bottom surface 1 of the protruding bottom portion 11b protruding in a semi-cylindrical shape is formed.
The guide hole 12a of the ball fitting / inserting portion 12 corresponding to 1c is also a spherical seat surface 12b. A flange 11d is formed around the spherical seat 11a on which the ball 4 is seated.

Even with the above configuration, the ball 4 will not come off from the arcuate groove 5a by the same operation as in FIG. FIG. 4 shows the operation when the position of the bore 6a is changed to the outer side in the radial direction R compared to the case of FIG. 3, and the shoe 11 swings so that the spherical seat 11a faces inward to move the ball 4 The arc groove 5a is not separated.

Various materials can be selected for the shoe 11 of the above-described embodiment, the slidability of the ball 4 can be improved or abnormal noise can be prevented from occurring, and the durability of the compressor can be improved.

In the assembly method of each embodiment, the shoe 11 is provided with the guide hole 12a by providing a partial cutout communicating with the guide hole 12a.
Then, the ball 4 may be fitted and inserted between the piston 3 and the cam member 5.

[Effect of device]

As described above, according to the present invention, the ball that rolls in the circular arc groove in line contact is not regulated on the piston side seating position, and the ball is always rolled in the circular arc groove on the cam side so that the ball and the circular arc groove move. It is effective in reducing uneven wear and improving durability.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a compressor according to the present invention,
FIG. 2 is an enlarged view for explaining the operation of the embodiment shown in FIG. 1, and FIG.
FIG. 4 is a constitutional view showing another embodiment, FIG. 4 is an explanatory view for explaining the operation of FIG. 3, FIG. 5 is a sectional view showing an example of a conventional compressor, and FIG. 6 is a compression of FIG. It is explanatory drawing explaining the operation | movement of a ball when attachment variation etc. arise in a machine. 1 ... Compressor, 2 ... Drive shaft, 3 ... Piston, 4 ...
Ball, 5 ... Cam member, 6 ... Cylinder block, 9
…… Discharge chamber, 10 …… Suction chamber, 11 …… Shoe, 12 …… Ball insertion part, 5a …… Arc groove, 11a …… Spherical seat, 11c …… Flat bottom 11c, 12a …… Guide hole, 12b …… flat seating surface 12.

Claims (1)

[Scope of utility model registration request] 1. A cylinder block in which bores are arranged side by side, a drive shaft rotatably supported by the cylinder block, and a drive shaft mounted on the drive shaft and curved in a circumferential direction on both side surfaces of a cam plate portion. A cam member having a circular arc groove having a desired center diameter, a piston reciprocating in the bore according to the displacement of the cam plate portion due to the rotation of the drive shaft, and a fitting member inserted between the piston and the cam plate portion. A front side ball and a rear side ball, one surface of which is fitted into the circular arc groove and rolls on the circular arc groove, and a piston side bearing surface that receives the other surface of these balls, in a radial direction about the drive shaft. A compressor having a swingable shoe and a shoe.