JPS61149588A - Swash plate type compressor - Google Patents

Abstract

PURPOSE:To enhance the seizure resistance and lubricity by forming the sliding surface between a swash plate and a shoe so as to have an arched-shape high in the middle and low in both ends, and forming a wedge-shaped clearance of the sliding surface to assist the formation of oil film. CONSTITUTION:A swash late is fixed on a turning shaft through a boss 11. The swash plate part 12 of the swash plate is engaged with a piston via a shoe 2. The cross-section of this swash plate part 12 cut in the direction C perpendicular to the sliding direction of the shoe 2 is formed to an arched sliding surface P high in the middle and low in both ends. And, it is so constituted that a wedge-shaped clearance is formed between this arched sliding surface P and the shoe 2 so that the oil film of lubricant is liable to be formed.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a cylinder block having a rotating shaft, a plurality of cylinder bores provided parallel to the rotating shaft, a swash plate rotated by the rotating shaft, and a cylinder block having a plurality of cylinder bores provided in parallel with the rotating shaft. This relates to a swash plate type compressor, which is composed of a piston that is slidably fitted within the compressor, and a shoe that is interposed between the piston and the swash plate and causes the piston to reciprocate as the swash plate rotates. be.

[Prior art]

In this type of swash plate type compressor, the sliding surface of the swash plate is a flat surface, and the sliding movement of the shoes is flat, and large loads and sliding speeds act on the sliding surfaces of the swash plate and shoes. In particular, the plate thickness accuracy of the swash plate and the flat Fn accuracy of the layer surface are exactly 11! was managed. As a result, an oil film is less likely to form on the sliding surface between the swash plate and the shoes, and seizing is particularly likely under severe sliding conditions such as no lubrication at startup or heavy loads during WI11i1. There is a problem.

As a countermeasure, conventional methods have been used to prevent seizure of the swash plate and shoes.
The material of the swash plate and shoes, especially the material of the surface that forms the sliding surface, and the shape of the sliding surface of the shoe are devised.

[Problem that the invention seeks to solve]

The present invention aims to solve the problem of forming the sliding surface of the swash plate with the shoe into a shape that allows an oil film to be formed promptly not only during startup but also during operation. The object of the present invention is to provide a swash plate compressor with excellent seizure resistance by improving the shape.

(Means for solving the problem of the same layer) The swash plate compressor of the present invention has a cross-section obtained by cutting the sliding surface of the swash plate with the shoe at least in a direction perpendicular to the sliding surface and the sliding direction of the shoe. The intersection line formed by the two is arched with a high center and low ends.

The swash plate compressor of the present invention consists of components such as a swash plate, shoes, pistons, rotating shaft, and cylinder block, and the shapes of these components are the same as those of conventional swash plate compressors except for the shape of the vibration surface of the swash plate. good.

In the swash plate compressor of the present invention, the swash plate refers to a member that is rotated and oscillated by a rotating shaft facing the bore of the cylinder block.

The shoe refers to something that slides on the sliding surface of the swash plate and causes the piston to reciprocate as the swash plate rotates. Accordingly, the shoe may have a hemispherical shoe, a flat shoe, or other shapes.

The swash plate, which features the swash plate compressor of the present invention, has a line of intersection formed by its sliding movement and a cross section cut at least perpendicular to the sliding direction of the sliding surface, which is high in the center, and at both ends. It is low arched.

As shown in Figure 1, which is a perspective view of a typical swash plate, the slant I/M
1 is a boss portion 1 having a boss hole 11a fixed to a rotating shaft.
1 and a swash plate portion 12 integrally formed obliquely with respect to the boss hole 11a.

Both surfaces 12a of this swash plate portion 12 serve as sliding surfaces. here,
The sliding direction of the shoe is a direction surrounding the boss portion 11, as shown by an ellipse A. The direction perpendicular to the sliding direction is the radial direction with respect to the boss portion 11 indicated by arrows B and C in FIG. FIG. 2 shows an enlarged and exaggerated view of the plate portion in cross section cut in the perpendicular direction. The arcuate solid line in FIG. 2 is the intersection line formed by the sliding movement and the cross section.

In the present invention, at least the above-mentioned intersection line needs to be arcuate with a high center and low ends.

Examples of surfaces with such intersecting lines include a part of the surface indicated by the symbol @S, which is a part of the lateral surface of the donut-shaped object shown by the solid line in Fig. 3-a, and A part of the surface indicated by the symbol T on the surface of the sphere indicated by the solid line in FIG. 1 can be exemplified. In addition, in this explanation, circular includes a perfect circle, an ellipse,
A sphere includes a perfectly round sphere and an elliptical sphere. In practice, the radius of curvature of the arcuate lines may be different or may vary.

In addition, when the sliding surface is a part of one spherical surface, all the intersection lines of cross sections cut in any direction on the sliding surface and the vibrating surface have an arcuate shape with a high center and low ends.

The cross section of the swash plate whose sliding surface is the S surface in FIG. 3 is exaggerated in FIG. 3-b, and the cross section of the swash plate in FIG. It is shown in Figure 4-b.

The degree of arching is determined by the distance between the periphery of the shoe and the sliding movement of the swash plate when the center of the shoe is in contact with the sliding surface, as shown in Figure 2, where the shoe sliding in contact with the vibration surface is indicated by a chain line. X is 1~
The thickness is preferably about 25μ, preferably about 5 to 8μ.

The surface of the swash plate that forms the sliding motion of the swash plate may be subjected to surface treatment to more completely prevent seizure. For example, it is preferable that the swash plate is made of an Al-8+gold alloy, with hard giant crystals of primary silicon exposed on the sliding surface, or that the surface is anodized to form an alumite layer. As another method, it is also preferable to form a WJWI agent layer containing molybdenum disulfide on the sliding surface.

As the shoe that slides into contact with the vibration surface of the swash plate, a conventional shoe with a flat Wt trend can be used as is.

Particularly good is one in which the central part of the vibrating surface is protruding and the peripheral part is low. Furthermore, it is preferable to have a small recess in the center that also serves as a holding area for lubricating oil. Like the sliding surface of the swash plate, it is preferable that the sliding movement of the shoes be subjected to a surface treatment with excellent seizure resistance and lubricity.

〔Effect of the invention〕

In the swash plate type compressor of the present invention, the I of the swash plate is
T'! It is partially convex, even if the surface is not convex.

Therefore, a transverse gap is formed at least partially at the peripheral edge of the shoe between the swash plate and the shoe 1-. Therefore,
When the shoe swings during startup, the starting torque decreases, and the swash plate and shoe slide relative to each other, lubricating oil is drawn between the swash plate and shoe through this wedge-shaped gap, increasing the amount of lubrication. Oil will be present on the sliding surfaces of the swash plate and shoes. Therefore, the possibility of direct contact between the swash plate and the shoes is reduced, the formation of an oil film is promoted on the sliding surfaces of the swash plate and the shoes, and the area in which the swash plate and shoes come into direct surface contact is reduced. By doing so, seizures caused by direct contact are also reduced. In particular, since the shoe rotates on its own axis due to the rotation of the swash plate, the supply of lubricating oil from the periphery of the shoe is further improved. Specifically, Figure 3-
In the swash plate shown in b, the shoes are in line contact with the swash plate, so they are easy to swing in the left and right directions with respect to the sliding direction. Furthermore, when the shoe reciprocates at the top of the sliding movement, it is even easier to swing. Further, in the swash plate shown in FIG. 4-b, the shoes are in point contact with the swash plate, so that they can swing back and forth and from side to side, making it easier to swing.

(Example 1) A sectional view of a swash plate compressor according to an example of the present invention is shown in the fifth example.
As shown in the figure. In FIG. 2, 3 is a cylinder block, and inside this cylinder block 3, a rotating shaft 4 is mounted with a bearing 41.
The swash plate 1 is rotatably supported via a shaft 42, and the swash plate 1 is connected and fixed to the rotating shaft 4. Cylinder bores 31 are formed in the cylinder block 3 at equal radial intervals, and a piston 32 is slidably fitted into each bore 31. The left end opening of the cylinder block 3 is opened by a pulp plate 33 and a front housing 34, and the right end opening is opened by a pulp plate 35 and a rear housing 36.

A concave portion 32a for receiving the outer peripheral portion of the swash plate 1 is formed in the center portion of the piston 32, and a spherical concave portion 32b is formed on each axially opposing surface of the concave portion 32a. Between the sliding movement of the swash plate 1 and the concave portion 32a of the piston 32, a hemispherical shoe 2 is disposed so as to be able to freely come into sliding contact with the swash plate 1 so as to reciprocate and transmit the rotation of the swash plate 1 to the piston 32. It has become. The above configuration is basically the same as that of a conventional swash plate compressor, except for the shape of the sliding surface of the swash plate 1.

In this embodiment, the shape of the sliding surface of the swash plate 1 is different from the conventional one. That is, the sliding surface of the swash plate according to this embodiment is
As shown in FIG. 2, a cross section of the 'ram moving surface taken in a direction perpendicular to the WI moving direction has an arcuate shape with a high center and low ends.

The first swash plate uses an Al-3i alloy as a base material, manufactures the swash plate using the usual method, attaches this swash plate to the rotating shaft, smoothes the sliding surface with vapor, a grindstone, etc., and then Finish polishing was performed to form the sliding surface into the shape shown in Fig. 4-b. The degree of this cross-sectional arcuateness is approximately 8 in the size of X in Figure 2.
It was μ.

The second swash plate is of the same material dimensions as the first swash plate,
At the surface finishing stage, it is formed to have the surface shown in Figure 3-b. The degree of this cross-sectional arcuateness was approximately 5μ, as indicated by the size of X in FIG.

5L is used as the base material for the shoe, which is the mating material for sliding.
IJ-2 was used, and the radial sliding surface was hardened such as carburizing and formed into a cylindrical shape, and the entire surface was coated with zinc phosphate.

Swash plate type compressors combine the above two types of swash plates and this shoe, and are No. 1 and No. 1 shown in the table.

Two types of compressors were manufactured by G4.

Furthermore, for reference, we will discuss swash plate compressor No. 3, which is a conventional swash plate compressor that combines a smooth swash plate whose sliding surface is not a spherical surface and the above-mentioned shoes. -I did.

Next, these three types of swash plate compressors were installed in a rotating test equipment, and the rotation speed of the compressor was approximately 4,000 to 6.
A high-speed seizure experiment was conducted by rotating the engine at 500 rpm.

The results are summarized in the table, and the mark AO indicates that the test passed without any burning, and the mark Δ indicates that there was some burn-in.

Seizing was observed in some of the compressors (No. 3) whose swash plate had a flat sliding motion. Compressors with spherical sliding surfaces (No. 1 and No. 2) did not suffer from seizure.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a swash plate according to the present invention, Fig. 2 is an enlarged cross-sectional view taken in the direction B of Fig. 1, Fig. 3-a is a perspective view of an elliptical ring, and Fig. 3-b is a perspective view of a third swash plate. Figure 4-a is a perspective view of a sphere; Figure 4-b has a partial surface the same as that shown in Figure 4-a. A schematic cross-sectional view of a swash plate. FIG. 5 is a cross-sectional view of a swash plate compressor according to an embodiment. In the figure, 1 is a swash plate, 2 is a shoe, 3 is a cylinder block,
32 is the piston

Claims (1)

[Claims] (1) A cylinder block having a rotating shaft, a plurality of cylinder bores provided parallel to the rotating shaft, a swash plate rotated by the rotating shaft, and a piston slidably fitted into the cylinder bore. and a shoe that is slidably interposed between the piston and the swash plate and causes the piston to reciprocate by rotation of the swash plate, the swash plate sliding with the shoe. The sliding surface is an oblique shape in which the intersection line formed by at least the sliding surface and a cross section cut in a direction perpendicular to the sliding direction of the shoe has an arcuate shape with a high center and low ends. Plate compressor.