JPH0444866Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a compressor that compresses fluid.

Prior Art Conventionally, for example, a wave-shaped cam compressor has a sine wave shape with unevenness in a direction parallel to the rotation axis of a rotary shaft 2 supported by housings 7 and 8, as shown in FIG. Forming the rotating shaft 2
a cam plate 53 integrally fixed to the cam plate 53; a plurality of pistons 3 slidably supported in the cylinder 6 parallel to the rotation axis; and the cam plate 53.
The cam plate 53 is made up of a plurality of balls 4, etc., which roll in contact with both sinusoidal rolling surfaces 53a and attach the piston 3 to the cam plate 53. Furthermore, FIG. 7 is an enlarged view of the piston 3 taken along the line A-A in FIG. is in contact with the ball catch 3
b and the diameter of the surface of the ball 4 are almost the same.

Problems to be Solved by the Invention In the compressor with the conventional configuration, the balls are always in contact with and rolling against the sinusoidal rolling surface 53a of the cam plate, but the contact surface is a point contact. The high surface pressure applied here significantly accelerates the wear of the rolling surface 53a of the cam plate 53, increasing the clearance and causing abnormal noise.
There was a problem with durability.

The problem that this invention attempts to solve is to increase the contact area between the balls and the sinusoidal rolling surface of the cam plate, reduce surface pressure, suppress wear, and improve the durability of the compressor. It is something.

Means for Solving the Problems The gist is that the rolling surface that contacts the balls on the cam plate is formed so as to be in line contact with the balls.

Function: The contact area between the balls and the sinusoidal rolling surface of the cam plate expands from dots to lines, and the contact pressure decreases inversely to this, significantly suppressing cam plate wear.

Embodiment The first embodiment of the present invention will be described below in Fig. 1-
This will be explained according to FIG.

In the compressor 1 shown in FIG. 1, the rotating shaft 2 includes a front housing 7, a rear housing 8,
The cam plate 5 is rotatably supported via bearings 9 and 9', and the cam plate 5 is integrally fixed thereto. As shown in FIG. 2, the cam plate 5 has sinusoidal rolling surfaces in the front and rear directions parallel to the rotation axis of the rotary shaft 2, and in this embodiment, the cam plate 5 has two concave and convex portions each. A periodic cam plate is used. Further, the cam plate 5 is provided with a ball groove 5a which is cut in the circumferential direction on the front and rear rolling surfaces so that the cut surface is an arc.

In addition, a ball 4 made of steel, ceramic, etc.
are fitted to be able to roll in the ball groove 5a, and the surfaces of the ball groove 5a and the ball 4 are formed to have approximately the same diameter so that the contact state is a line contact in the radial direction of the cam plate 5, Surface pressure is evenly distributed over the entire line contact surface.

Further, a piston 3 having a concave center portion is mounted on the ball 4 on the opposite side of the contact surface with the ball groove 5a via a ball seat 3a. FIG. 3 is an enlarged view of the piston 3 taken along the line A-A in FIG. It has a semi-cylindrical surface, and the diameter of the surface is made almost the same so that the ball receiving seat 3a and the ball 4 are in surface contact with each other.

The piston 3 is attached to the cam plate 5 via a ball 4, and is supported by a cylinder 6 so as to be slidable in a direction parallel to the rotation axis of the rotary shaft 2.
When the rotating shaft 2 rotates once following the rotation, it reciprocates twice within the cylinder in the direction of the rotating shaft.

In the above configuration, when the rotating shaft 2 receives power from the outside through a fan belt or the like and rotates,
Accordingly, since the ball 4 is fixed by the piston 3 in a direction perpendicular to the rotation axis of the rotary shaft 2, it rolls within the ball groove 5a of the cam plate 5 and slides within the ball seat 3a of the piston 3. move. At this time, since the cam plate 5 and the balls 4 are in line contact and the surface pressure applied to the cam plate 5 is low, wear on the ball rolling surface is significantly reduced.

On the other hand, in the compressor assembly method according to the present invention,
When fitting the cam plate 5 after fitting the ball into the conventional ball receiving seat 3b, if the ball groove depth on both sides of the cam plate 5 exceeds the wall thickness deviation of the cam plate, a part of the ball groove 5a is formed. Since the gap between the two facing balls 4 is narrower than the thickness of the outer periphery of the cam plate, assembly becomes impossible.

Therefore, in this embodiment, a new ball seat 3a is provided on the piston 3, and during manufacturing, the balls 4 are first fitted into the ball grooves 5a on both sides of the cam plate 5, and then the concave shape of the ball seat 3a is fitted. The ball 4 is inserted into the semi-cylindrical part and assembled.

Next, a second embodiment of the present invention will be described with reference to FIG.

The rotating shaft 2, ball 4, piston 3, ball seat 3b, etc. are completely the same as the conventional ones, but the ball groove 51a provided on the ball rolling surface of the cam plate 51 has the above-mentioned inner peripheral surface. A cylindrical surface similar to the ball groove 5a of the first embodiment is recessed, and the outer peripheral surface is cut in a plane perpendicular to the rotation axis.

In the compressor having such a structure, the ball groove 51a of the cam plate 51 and the ball 4 are in line contact, similar to the first embodiment. However, the contact area is about half that of the embodiment described above, and although the surface pressure increases to some extent, the effect is not much different from that of the embodiment described above when compared with conventional point contact, and wear can be significantly reduced.

In the assembly method of this embodiment, the ball 4 is fitted into the ball seat 3b of the piston 3, and then the cam plate 51 is inserted and the assembly is performed as in the conventional method.

In this embodiment, the only difference from the conventional model is the ball groove 51a of the cam plate 51, and the above effects can be obtained by simply making a change in this point to the conventional model.

Next, a cam plate 52 of a third embodiment of the present invention is shown in FIG. 5, and will be described based on this figure.

In this embodiment, the cam plate 2, ball 4, piston 3, ball seat 3b, etc. are completely the same as the conventional ones, and the ball groove 52a of the cam plate 52 is also the same as the ball groove 5a of the first embodiment.
The cam plate 52 has a semi-cylindrical notch coaxially formed in a part of its outer peripheral wall that forms part of the ball groove 52a.

Since the compressor equipped with the cam plate 52 has the same ball seat 3b as in the prior art, the contact between this and the balls 4 is the same as in the prior art, while the contact between the balls 4 and the ball seat 52a is The rollers also roll in the same line contact as in the first embodiment. By providing the partially cutout portion 52b, the contact area of the ball 4 rolling on the ball groove 52a having this portion is reduced, but in this point it is similar to the second embodiment. is not a problem.

In the assembly method according to this embodiment, after the ball 4 is fitted into the ball seat 3b of the piston 3, the ball 4 is inserted into the notch 5 of the cam plate 51.
2b to fit it into the ball groove 52a, roll on it to shift it, and then insert it into the notch 52b.
Then, the ball 4 fitted with another ball seat 3b is fitted into the inserted ball groove 52a, and such assembly is repeated until the number of pistons is specified.

In this embodiment, the ball 4 is connected to the ball catch 3.
By widening the contact area of both ball groove 52a and ball groove 52a as much as possible, the surface pressure can be lowered, and the effects of the present invention can be further exhibited.

The present invention is not limited to the first to third embodiments, and may be applied to a cam type compressor using a flat swash plate as the cam plate without departing from the gist of the present invention. You may do so.

Effects of the invention As detailed above, according to the invention, the contact area between the rolling surface of the ball on the cam plate and the ball is formed to be a line contact, thereby increasing the contact area. Since it is possible to reduce surface pressure and suppress wear, it has the excellent effect of preventing an increase in clearance and the generation of abnormal noise due to it, and significantly improving durability.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a cam compressor according to a first embodiment of the present invention, FIG. 2 is a layout diagram of the piston, cam plate, and balls of the compressor, and FIG. 3 is a cross-sectional view taken along line AA in FIG. 1. A sectional view of a main part showing a piston in
Fig. 4 is a cross-sectional view of essential parts of a compressor according to a second embodiment of the present invention, Fig. 5 is a plan view of a cam plate according to a third embodiment of the present invention, and Fig. 6 is a sectional view of a cam type compressor according to the prior art. A sectional view, FIG. 7 is a sectional view of a main part of the piston taken along the line AA in FIG. 6. 2...Shaft, 3...Piston, 3a, 3b
...Ball catch, 4...Ball, 5, 51, 52
...Cam plate, 5a, 51a, 52a...Ball groove, 6...Cylinder block, 7,8...
housing.

Claims (1)

[Scope of utility model registration request] a rotating shaft; a cam plate that rotates integrally with the rotating shaft and is fixed perpendicularly to the rotating shaft of the rotating shaft; a housing that supports the rotating shaft; In a compressor having a piston whose movement is regulated and which is mounted via a ball that rotates in constant contact with both surfaces, a suction valve, a discharge valve, etc., the rolling motion contacts the ball on the cam plate. A compressor characterized in that a surface is formed to be in line contact with the ball.