JPS5888473A - Slidable member sliding on at least two kinds of members in compressor or the like - Google Patents

Abstract

PURPOSE:To improve antiwear property and anti-baking property in vanes or the like of a vane compressor by varying the exposure degree of primary crystal silicon grains on the slide surface of aluminum-silicon alloy according to the hardness of member opposed thereto. CONSTITUTION:Vanes 18 contact slidably a cylinder 11, both side plates 12, 13 and a rotor 17 having three kinds of hardness Hv220, 220, 700. The end surface 18a and side surfaces 18b, 18c respectively contact slidably a cylinder 11 and both side plates 12, 13 with high speed low load so that the exposure degree of primary crystal silicon grains 9 is lowered and wear is few without damaging sliding opponents. However, since the belly and the back 18d, 18e have low speed large load, they have high exposure degree and few wear. Since this exposure degree tends to strip off silicon grains 9 by increasing finishing allowance, the exposure degree can be varied by varying the final finishing allowance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a contact member which is made of an aluminum-silicon alloy and comes into sliding contact with two or more types of members having different hardness, such as the swash plate of a swash plate compressor or the vane of a vane compressor. It is related to.

Generally, as shown in Fig. 1, a swash plate type compressor has a swash plate 3 fitted and attached to a drive shaft 2 which is rotatably supported in a housing 1. A double-headed piston 5 is housed inside the cylinder 7.4 so as to be able to reciprocate, and a spherical part 5a is recessed to face the inside of the piston 5;
5b is engaged with a pair of hemispherical shoes 6.7, and the slope 3 of the swash plate 3 is engaged with the flat surfaces 6a, 7a of both shoes 6.7.
a, 3b are brought into sliding contact, and the outer peripheral surface 3c of the swash plate 3 is brought into sliding contact with the second
As shown in the figure, the end surfaces 5d and 5e of the connecting portion 5c connecting the head of the piston 50 were brought into sliding contact. When the swash plate 3 is rotated by the drive shaft 2, the piston 5 is reciprocated within the cylinder bore 4 to perform a compression action.

On the other hand, since the pair of shoes 6.7 interposed between the swash plate 3 and the spherical parts 5a and 5b of the piston 5 receive a large force during compression operation, their Vickers hardness Hv (hereinafter simply referred to as hardness Hv) is 650 or more. The swash plate 3 and piston 5 are made of an aluminum-silicon alloy containing 16% silicon (Fig. 3 (a), (b)). )
As shown in FIG. 3, each of the silicon substrates is formed of an aluminum base material 8, primary silicon grains 9, and eutectic silicon grains 9'. Further, the surface of the piston 5 is coated with a tetrafluoroethylene film 10, and the spherical parts 5a and 5b are coated with a tetrafluoroethylene film 10.
Alternatively, the wear of the end faces 5d and 5e is minimized to improve durability.

However, the conventional swash plate 3 has high hardness (hardness Hv1300~ Since the degree of exposure of the primary silicon grains of 1500) was the same, it could not be said that the conditions were suitable for each member stand in mutual contact with each other.

That is, if the amount of exposure of the primary silicon grains of the swash plate 3 is reduced and the amount of exposed aluminum base material on the outer circumferential surface 3c and the slopes 3a, 3b is increased to match the coating 10 of the piston 5, the hardness will decrease when lubrication is insufficient. Seizing occurs between the shoe with high hardness and the aluminum base material with low hardness, and the shoe 6.
If the degree of exposure of the primary silicon grains of the swash plate 3 is made relatively high in order to properly maintain sliding movement between the swash plate 3 and the swash plate 7, the coating 10 is likely to be scratched by the hard silicon particles and worn out. There was a defect that the piston base material was damaged after the coating was broken. There is also a piston 5 in which the coating 10 is omitted, but this also has the drawback that the end surfaces 5d and 5e suffer from severe wear and surface roughness.

The present invention was proposed in order to resolve the above-mentioned conventional contradictions, and its purpose is to provide a compressor swash plate etc. made of an aluminum-silicon alloy that comes into sliding contact with two or more types of members having different hardness. To provide a sliding member whose seizure resistance and abrasion resistance can be improved by changing the degree of exposure of primary silicon grains according to the hardness G of a member that contacts the sliding surface of the sliding member. There is a particular thing.

Hereinafter, a first embodiment in which the present invention is embodied in a swash plate of a swash plate type compressor will be described with reference to FIGS. 1 to 3.

In this embodiment, the slope 3 is in sliding contact with the shoe 6.7 of the swash plate 3.
Figure 3(a) shows the degree of exposure of the primary silicon grains 9 in a and 3b.
60% as shown in FIG.
The degree of exposure of the primary silicon grains 9 on the outer circumferential surface 3c in sliding contact with the primary silicon grains 9 is set to 10% or less as shown in FIG. 3(b). In addition, the shoe 6.7 is made of bearing steel (SUJ) with a surface hardness of 700 HV.
2), the piston is made of an aluminum-silicon alloy containing 12% silicon, and the outer peripheral surface is coated with a tetrafluoroethylene film 10, but this may be omitted in some cases.

By the way, since the degree of exposure of the primary silicon grains 9 of the swash plate 3 cannot be changed during molding of the swash plate base material, it is processed to the above-mentioned ratio when finishing the base material. That is, in this embodiment, after machining the slopes 3a and 3b using a lathe, the machining allowance for final processing such as superfinishing is approximately 20 to 40μ.

The degree of exposure of the primary silicon grains 9 of 3b is 10 to 60% (the degree of exposure of the outer peripheral surface 3c is set to 10% or less by setting the finishing allowance of the outer peripheral surface 3c to about 5 μ to 20 μm. Here, It is necessary to know the relationship between the finish machining allowance and the degree of exposure of the silicon grains empirically in advance by taking advantage of the tendency that the larger the finishing machining allowance makes it easier for the silicon grains 9 to peel off. Milling may be used, and in addition to super finishing, the final finishing includes polishing, vapor polishing, etc. Also, when intermediate finishing and top finishing processes are included, the machining allowance for the final finishing can be reduced.

The slopes 3a, 3b of the swash plate 3 and the shoes 6゜7 with the above structure slide at high speed and under a high load, but even if metal contact occurs due to lack of lubrication, the primary silicon grains 9, which are harder than aluminum, will absorb the load. Because of this, the aluminum base material 8 is less likely to experience surface roughness or wear. In addition, since the shoe 6.7 has a sufficiently high hardness, surface roughness and wear caused by the primary silicon grains 9G are extremely reduced.

Furthermore, the outer circumferential surface 3C of the swash plate 3 has a coating 1 on the end surfaces 5d and 5e.
0, but since the primary silicon grains are hardly exposed, the coating 10 is not scratched and there is little wear.

In this way, in the swash plate compressor of the above embodiment, the wear resistance or seizure resistance of the swash plate 3, the piston 5, the shoes 6.7, and the coating 10 are improved. A conventional compressor in which the degree of exposure of the primary silicon grains on the sliding surface was constant at all locations and a compressor according to the present invention were tested under the same conditions shown in Table 1, and Table 2 shows the results. Got the results.

In addition, in order to obtain results in a short time, this test uses less oil and more gas than normal tests, as shown in Table 1, and allows the liquid to back up without any cooling load, resulting in an extremely low oil viscosity. Also, the tests were conducted under harsh conditions where there was a temporary lack of lubrication immediately after startup.

As shown in Table 2 or 6' below, the slope 3a of the swash plate.

Table 1 - Table 2 ・In the case of a conventional swash plate in which the degree of exposure of primary silicon grains on both 3b and outer peripheral surface 3c is 60%, the phenomenon of piston coating wear and increased streaks on the piston base material occurs. Also, in the case of the conventional swash plate in which the exposure degree of the slopes 3a, 3b and the outer circumferential surface 3c were both 10%, seizure of the shoes and the swash plate occurred. On the other hand, the swash plate of the present invention shows no abnormality, and even when the coating 10 was not applied to the piston, good results were obtained in which there were some streaks on the outer circumferential surface 3C of the swash plate, but no particular abnormality was found. did it.

Next, an embodiment in which the present invention is embodied in a vane compressor will be described with reference to FIGS. 4 and 5.

Here, to describe the structure of the vane compressor in terms of two parts, front and rear side plates 12, 13 are fixedly connected to both end surfaces of the thick-walled horizontally cylindrical cylinder 11, and the front side plates 1-. A front housing 14 is fixedly connected to the front surface of the front housing 12e, and a rear housing in the shape of a horizontal inner cylinder with a bottom is attached to the rear end surface of the front housing 14 so as to fit into the outer peripheral surfaces of the cylinder 11 and both side seats 12 and 13. 15 are bonded and fixed.

A drive shaft 16 is rotatably supported at a position G which is eccentric by a certain distance from the center of the side plates 12 and 13 and the front housing 14. A cylindrical rotor 1 that locally slides into sliding contact with the inner surfaces of both side plates 12 and 13
7 are fixed together. A vane 18 is fitted into a plurality of vane grooves 17a provided on the outer circumferential surface of the rotor 17 so as to be retractable.
a is in sliding contact with the inner circumferential surface of the cylinder 11, and both end surfaces 18b
, 18c are in sliding contact with the sides of the side play) 12.13, and the ventral surface 18d and the back surface 18e are the vane grooves 1.
It is in sliding contact with the plane of 7a.

On the other hand, gas introduced into the suction chamber 2o formed in the front housing 14 through the suction port 19 provided through the outer periphery of the front housing 14 in the front side plate 12 is introduced into the cylinder 11. A suction hole 22 is provided therethrough to lead to a working chamber 21 formed by the rotor 17, the vane 18 and both side plates 12.13. Further, a discharge chamber 23 formed by cutting out the outer periphery of the cylinder 11 and the working chamber 21 communicate with each other through a discharge hole 24 and are normally closed through a check valve 25. The rear side plate 13
A passage 27 is provided that communicates the discharge chamber 23 with the oil separation chamber 26 of the rear housing 15, and the compressed gas sent under pressure to the oil separation chamber 26 is filtered for oil by a filter 28, and then passed through the outer periphery of the rear housing. It is transferred to the outside through a discharge port 29 provided in the. Note that 30 is a passage for guiding oil to the end surface of the rotor 17.

In this second embodiment, the vane 18 is a sliding member, and the cylinder f1. Both side plates 12.13・
and rotor 17 are in sliding contact. The composition and hardness Hv of these members are as shown in Table 3.

Table 3 Also, the cylinder 11 of the vane 18, the side plate 12.
13 and the tip surface 18a1 in sliding contact with the rotor 17, both sides 1
The experiment was conducted with the degree of exposure of the primary silicon grains on the antral (back) surfaces 18d (18e) and 8b, 18c as shown in Table 4, respectively.

The tip surface 18a of the vane 18 slides against the inner circumferential surface of the cylinder 11 at high speed and with a low load because the pressure in the working chamber 21 and the pressure acting on the inner end surface of the vane cancel each other out. Therefore, even if the primary silicon grains are not exposed, the tip surface 18a suffers little wear, and the inner circumferential surface of the cylinder is also less likely to be damaged by the silicon grains.

Further, since the side surfaces 18b and 18c of the vane 1B slide on the coating 1o of the front and rear side plates 12 and 13 at high speed and with a low load, almost no wear occurs on the side surfaces 18b and 18c. Furthermore, since the degree of exposure of the primary silicon grains is low, the coating 1o is not damaged.

Furthermore, although the belly (rear) surface 18d (18e) of the vane 18 slides at low speed on the vane groove 17a surface of the rotor 17, it receives a large load only when it hits the special edge. ,
A larger load acts at 22 points.

However, since the degree of exposure of the primary silicon grains on the vane belly (back) surface 18d (18e) is high, the above-mentioned large load is
The silicon grains allow the bridge to reduce wear on the vanes 18. Further, since the rotor 17 is also highly hard, it will not be damaged by silicon particles.

The vane compressor of this second embodiment and a conventional compressor in which the degree of exposure of the silicon grains of the vanes is the same in all parts are used.
When the test was conducted under the following conditions, the results shown in Table 4 were obtained.

Table 4 From this result, it is clear that the conventional vane (NO.

In a compressor using I and 1), the cylinder, side plate, or belly (rear) surface of the vane is prone to wear, but the compressor using the vane of the present invention reduces wear on each part and improves durability. , it can be seen that seizure is prevented.

In addition, in the first and second embodiments, the swash plate and vane of the compressor were described, but in addition to the compressor, a machine having a mechanism in which a member made of an aluminum-silicon alloy comes into sliding contact with two or more members of different hardness. If so, it is possible. Further, when the silicon content percentage of the aluminum-silicon alloy is increased, the amount of exposure may be changed as a whole.

As described in detail above, the present invention provides a sliding surface of a sliding member made of an aluminum-silicon alloy that is in sliding contact with two or more types of members having different hardness, so that primary silicon grains are exposed in accordance with the hardness of the members in relative contact with each other. By changing the degree, there is an effect that the wear resistance and seizure resistance of the sliding member and the member that makes sliding contact therewith can be improved.

[Brief explanation of the drawing]

Figure 1 is a partial vertical cross-sectional view of only the vicinity of the swash plate showing an example of a swash plate compressor, Figure 2 is a cross-sectional view of the central part of the swash plate, and Figures 3 (a) and (b) are aluminum FIG. 4 is a cross-sectional view showing the composition of a silicon alloy, FIG. 4 is a longitudinal cross-sectional view showing an embodiment of the present invention in a vane compressor, and FIG. 5 is a cross-sectional view of the same vane compressor. Swash plate 3, slopes 3a, 3b, outer peripheral surface 3c, piston 5, shoe 6.7, aluminum base material 8, primary silicon grains 9,
Tetrafluoroethylene coating 10, cylinder 11, front and rear side play H2, 13, rotor 17, vane groove 17a, vane 18, tip surface 18a, side end surface 18b,
18c, ventral (dorsal) surface 18d (18e). Patent Applicant Toyota Industries Corporation Agent Hironobu Onda ( ( [ [

Claims (1)

[Scope of Claims] l The sliding surface of a sliding member made of an aluminum-silicon alloy that comes into sliding contact with two or more types of members having different hardnesses, the degree of exposure of primary silicon grains is changed according to the hardness of the members in relative contact with each other. A sliding member that slides on two or more types of members in a compressor or the like. 2. The sliding member is a swash plate that slides on the piston and shoe of the swash plate compressor, and the degree of exposure of the primary silicon grains on the side surface that comes into sliding contact with the shoe of the swash plate is determined by A sliding member that slides with two or more types of members in a compressor or the like according to claim 1, wherein the exposure degree is higher than that of crystalline silicon grains. 8. The sliding member is a vane that comes into sliding contact with the cylinder, rotor, and side plate covering both end surfaces of the vane compressor, and the degree of exposure of the primary silicon grains on the sliding surface that comes into sliding contact with the rotor of the vane is determined by Two or more types of members in a compressor etc. according to claim 1, characterized in that the degree of exposure of the primary silicon grains on the sliding surface in sliding contact with the cylinder and the side plate is higher than that of the primary silicon grains, A sliding member that comes into sliding contact.