JP2003184743A - Shoe for swash plate type compressor and swash type compressor provided therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shoe made of an aluminium alloy and having favorable sliding characteristics and to provide a practical swash plate type compressor by constituting the swash plate type compressor using the shoe. <P>SOLUTION: A metal plated film 148 formed by electroless deposition and electroplating is formed on the surface of a shoe base material 146 made of an aluminium alloy. Metal plated films adopted here are an electroless nickel deposition film of Ni-P system, Ni-P-B-W system, etc., an electroless cobalt deposition film of Co-P system, etc., an electroless nickel cobalt deposition film of Ni-Co-P system, etc., a nickel electroplating film of Ni system, Ni-W system, Ni-Fe system, etc., a steel electroplating film of FE-P system, etc., a chrome electroplating film of Cr system, etc., and a cobalt electroplating film of Co-W system, etc. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shoe arranged between a swash plate and a piston in a swash plate compressor, and more particularly to a shoe made of aluminum alloy, and a swash plate compressor provided with the shoe. Regarding

[0002]

2. Description of the Related Art A swash plate compressor converts the rotation of a swash plate into a reciprocating motion of a piston to compress a gas, and a swash plate that rotates at a high speed and a piston that reciprocates at a high speed.
A shoe as a sliding member is provided to ensure smooth operation of both. For example, a swash plate compressor used for applications such as a vehicle air conditioner is required to be particularly lightweight, and the shoe, which is one of the constituent parts of the compressor, is made of aluminum to reduce the weight. It is thought to do.

[0003]

However, for example, a swash plate or a piston, which is a mating component with which a shoe slides, is often made of an aluminum alloy. In that case, the same kind of material is used. Since members made of a material containing the material as a main component are slid with each other, seizure easily occurs. Further, even when the swash plate or the piston is not made of an aluminum alloy, for example, even when a swash plate made of an iron-based material is used, the shoe slides under severe conditions, so that seizure may occur. In addition to such a problem of seizure, aluminum alloy has its strength,
Due to its low hardness, the shoe made of aluminum alloy is easily scratched on its surface, which scratches the sliding surface of the swash plate or the piston on the mating side, impeding good sliding contact properties. It also has the potential. In addition, since the conditions are severe, the lack of strength and hardness also contributes to poor durability.

Therefore, according to the present invention, by obtaining a shoe made of an aluminum alloy having good sliding characteristics, and by constructing a swash plate type compressor using the shoe,
The object was to obtain a practical swash plate compressor. Further, according to the present invention, a swash plate compressor shoe of each of the following aspects and a swash plate compressor provided with the shoe can be obtained. Each mode is divided into the same as the claims,
Number each section and enter the number in other sections as necessary. This is merely for facilitating the understanding of the present invention, and the technical features and combinations thereof described in the present specification should not be construed as being limited to those described in the following respective sections. . Moreover, when a plurality of items are described in one section, it is not always necessary to adopt the plurality of items together. It is also possible to select and use only some items.

In the following items, (1) item,
A combination of the items (2) and (8) corresponds to claim 1, and the item (21) corresponds to claim 2.

(1) A shoe arranged between a swash plate and a piston in a swash plate compressor, which is a base material made of an aluminum alloy and metal plating for coating at least a part of the surface of the base material. A shoe for a swash plate type compressor including a coating. That is, the swash plate compressor shoe of the present invention is characterized by forming a metal plating film on the surface of an aluminum alloy shoe. Due to the presence of this metal plating film, good sliding characteristics can be obtained.

Various metal plating films can be used. A specific mode of the metal plating film will be described in the following section. The preferred composition and film thickness of each metal plating film will be described later in the [Embodiment Mode]. The method of forming each metal plating film, that is, the plating method is not particularly limited, and the point that the surface treatment of the shoe is performed according to the method usually performed for other products in other technical fields. Considering this, it may be performed under appropriate conditions. In addition, each of the metal plating coatings specifically described below may be adopted independently, that is, the metal plating coating of the shoe may be formed by only one layer of the metal plating coatings. A mode in which the metal plating film of the shoe is formed by laminating the shoes may be used.

The type of aluminum alloy forming the base material is not particularly limited. Aluminum-based alloys that have been conventionally used and various known aluminum-based alloys can be used. More specifically, for example, Al-around the eutectic composition such as A4032
A Si-based alloy can be used. The Al-Si alloy has a small coefficient of thermal expansion and good wear resistance, and when this alloy is used, it becomes a shoe having good sliding characteristics.
In addition, for example, Al-Cu such as A2017 and A2024.
An Mg-based alloy can be used. Al-Cu-M
Since the g-based alloy has high strength, if this alloy is used,
A shoe with high strength and excellent durability.

(2) The metal plating film is Ni, Co
The shoe for a swash plate compressor according to item (1), which comprises an electroless plating film containing at least one of the above as a main constituent element. Nickel-based or cobalt-based electroless plating can form a uniform metal plating film, and the hardness of the plating film is relatively high, so that a shoe having good sliding characteristics can be obtained.

(3) The electroless plating film is Ni-P
System, Ni-B system, Ni-P-B system, Ni-P-W system, N
The shoe for a swash plate compressor according to item (2), which contains an electroless nickel plating coating of either i-B-W type or Ni-P-B-W type. In addition to being able to form a uniform metal plating film, electroless nickel plating has a high hardness of Vickers hardness Hv500 or more at the time of deposition,
Excellent wear resistance and corrosion resistance. Therefore, the shoe having the metal plating film formed by the electroless nickel plating can sufficiently suppress the generation of scratches such as the deformation of the aluminum alloy base material, and the sliding characteristics and durability. Excellent shoe for swash plate type compressor.

Explaining the advantages of each plating film, Ni-P type electroless nickel plating has excellent adhesion to an aluminum alloy as a base material, has a high film forming rate, and costs for plating a plating bath material or the like. It is cheap and has excellent corrosion resistance. The Ni-B type and Ni-P-B type electroless nickel plating has high hardness and is excellent in wear resistance and high temperature oxidation resistance. Particularly, in the Ni-P-B system, the hardness thereof can be Hv650 or more at the time of precipitation. Ni-P
In the -W type, Ni-B-W type, and Ni-P-B-W type electroless nickel plating, a coating film having further excellent abrasion resistance can be formed by the effect of W contained. Appropriate ones may be adopted in view of their respective advantages.

The electroless nickel coating may be formed by laminating two or more electroless nickel plating layers having different compositions. Therefore, “any” in this section is not necessarily meant to include only one of the listed. In the following paragraphs, the meaning of "any" in the case where a plurality of types of plated coatings are listed shall be interpreted in the same way as this paragraph. That is, it means that two or more kinds of the listed plating films are laminated to form one plating film.

(4) The electroless plating film is Co-P
The shoe for a swash plate type compressor according to item (2) or (3), which contains an electroless cobalt plating film of either a Co-PW system or a Co-P-W system. The electroless cobalt-plated coating has excellent frictional characteristics, and because of this advantage, the sliding characteristics of the shoe are good.

(5) The electroless plating film is Ni-C
The shoe for a swash plate compressor according to any one of items (2) to (4), which comprises an electroless nickel-cobalt plating film of either o-type or Ni-Co-P type. The electroless nickel-cobalt plating film also has excellent friction characteristics and a shoe having excellent sliding characteristics can be obtained.

(6) The shoe for a swash plate type compressor according to any one of items (2) to (5), wherein the electroless plating film is obtained by co-depositing polytetrafluoroethylene (PTFE). When PTFE is co-deposited in the electroless plating film, the film becomes a film having excellent lubricating properties and the sliding properties of the shoe are improved.

(7) The metal plating film, the electroless plating film, Sn, TiCN, TiN, CrN, Ti
And a coating formed on the surface of the electroless plating coating containing at least one of AlN (2) to (6)
A shoe for a swash plate compressor according to any one of items. The Sn-containing coating functions similarly to a solid lubricant because Sn is a soft metal, and has excellent slidability when lubrication with oil is poor, and a coating containing TiCN, TiN, CrN, or TiAlN is Excellent hardness due to high hardness. Therefore, if the above coating is formed on the surface of the electroless plating coating, good sliding characteristics can be obtained. The Sn-containing coating may be formed by electroplating or chemical plating (displacement plating), such as TiCN or Ti.
PVD for coatings containing N, CrN, TiAlN
It may be performed by a method such as (physical vapor deposition).

(8) The metal plating film is Ni, F
The shoe for a swash plate compressor according to any of (1) to (7), which comprises an electroplating film containing at least one of e, Cr and Co as a main constituent element. Among the electroplated coatings, those containing the above-listed main constituent elements are suitable as the surface coating of the shoe made of aluminum alloy because a hard plated coating can be formed. In addition, since electroplating is generally lower in cost than electroless plating, an inexpensive shoe can be obtained.

(9) The electroplated coating is Ni-based, N-based
i-P system, Ni-W system, Ni-Fe system, Ni-Mo-W
The shoe for a swash plate compressor according to item (8), which comprises any one of the electro-nickel plated coatings of the system. The electro-nickel plating film is less likely to cause defects such as pinholes and cracks,
It has an advantage that it has a smoothing effect (leveling) that compensates for the roughness of the base material, and that it can also obtain hardness. By virtue of this advantage, the shoe made of an aluminum alloy coated with an electric nickel plating film has good sliding characteristics.

(10) The electroplated film is Fe-based,
The shoe for a swash plate compressor according to item (8) or (9), which contains an Fe-P-based, Fe-W-based, Fe-C-based, or Fe-N-based electroiron plating film. Electric iron plating has the advantage of low cost. Therefore, a low-cost shoe is realized.

(11) The electroplated film is a Cr-based material,
Includes any of the Cr-Mo electroplated coatings
The shoe for a swash plate compressor according to any one of items (8) to (10). The electrochromic plating film has a higher hardness and a smaller friction coefficient than the above-mentioned electronickel plating. Therefore, a shoe having good sliding characteristics can be obtained.

(12) The electroplated coating is a Co-based coating,
Includes any Co-W based electro-cobalt plating film
The shoe for a swash plate compressor according to any one of items (8) to (11). The electro-cobalt plated film has excellent frictional characteristics, and in that respect, a shoe having good sliding characteristics can be obtained.

(13) The metal plating film is SiC,
At least 1 selected from Si ₃ N ₄ , Al ₂ O ₃ and CrC
The shoe for a swash plate type compressor according to any one of the items (1) to (12). All of the substances listed above have high melting points and high hardness, and the metal plating coating containing them is a coating with excellent abrasion resistance, and the sliding characteristics of the shoe made of aluminum alloy are further improved. It These substances may be contained, for example, as fine particles, and can be contained in the coating film by being dispersed and added in the plating bath when forming the metal plating coating film.

(14) The metal plating film is Hv30
The shoe for a swash plate compressor according to any one of (1) to (13), which has a hardness of 0 or more. Vickers hardness Hv30
By forming a film having a hardness of 0 or more, a shoe made of an aluminum alloy having practically sufficient performance can be obtained. In order to further improve the characteristics such as abrasion resistance and scratch resistance of the shoe, Hv500 or more is desirable, and Hv600 or more, or even Hv70.
It is desirable to set it to 0 or more. On the contrary, from the viewpoint that the excessive wear of the mating member on the sliding side is suppressed, or that the mating member is less likely to be damaged by the loosened material even when a part of the coating is missing and loosened, Hv15
It is preferably 00 or less, and more preferably Hv1100 or less.

(15) The shoe for a swash plate type compressor according to any one of the items (1) to (14), wherein the metal plating film covers at least a portion in sliding contact with the swash plate. In the swash plate compressor, the shoe is in sliding contact with the piston and the swash plate. Therefore, good sliding characteristics can be obtained by coating the portion of the surface that is in sliding contact with them with a metal plating film. In particular, considering that the swash plate rotates at a high speed, it is desirable to form a film on at least a portion that is in sliding contact with the swash plate as in the aspect described in this section. Incidentally, considering the shoe's corrosion resistance, shape stability, ease of plating treatment, etc.,
It is desirable to apply a plating film on the entire surface.

(16) The shoe for a swash plate type compressor according to any of (1) to (15), wherein the metal plating film is exposed.
The swash plate compressor shoe of the present invention may be one in which another coating, for example, a lubricating coating made of a synthetic resin containing a solid lubricant is formed on the surface on which the metal plating coating is formed. . Such a lubricating coating improves sliding properties. In that case, the solid lubricant may be, for example, MoS.
₂ (molybdenum disulfide), BN (boron nitride), WS
₂ (tungsten disulfide), graphite, PTFE
(Polytetrafluoroethylene) or the like can be adopted, and as the synthetic resin, polyamide imide, epoxy resin, polyether ketone, phenol resin or the like can be adopted. As a method of forming the lubricating coating, for example, a method in which a synthetic resin in which a solid lubricant is dispersed is applied to the surface of the metal plating coating by a tumbler treatment, a spray treatment, or the like and the resin is cured can be adopted. On the contrary, as in the embodiment described in this section, it is possible to apply no other coating to the surface of the metal plating film. A shoe that does not have an additional coating has a low manufacturing cost and is a practical shoe.

Although various aspects of the swash plate compressor shoe of the present invention have been described above, the technical features of each aspect of the swash plate compressor described later are intended to limit the use of the shoe of the present invention. As a feature, it is also possible to apply to the shoe of the present invention.

(21) A swash plate and a piston are provided, and the shoe for a swash plate compressor according to any one of the items (1) to (16) is arranged between the swash plate and the piston. A swash plate type compressor characterized by that. The swash plate type compressor of the present invention is a swash plate type compressor provided with the shoe of the present invention, and the swash plate type compressor excellent in durability that enables smooth operation due to the good sliding characteristics of the shoe. Becomes

(22) The swash plate compressor according to item (21), wherein the swash plate is made of an iron-based material. The iron-based material is inexpensive, and the swash plate compressor including the swash plate made of the iron-based material is inexpensive. Further, for example, in a variable displacement swash plate compressor, a change in compressor capacity is adjusted by an angle (tilt angle) formed by the swash plate and a rotation axis of the swash plate. It is desirable that the inclination angle of the swash plate is constant. If the weight of the swash plate is increased to some extent, the inclination angle of the swash plate is stabilized by its inertial force. A swash plate made of an iron-based material has a heavy weight, and a variable capacity type swash plate compressor having an iron-based swash plate has excellent swash plate stability. In such a variable displacement type swash plate compressor, by combining a shoe sliding with the swash plate with a shoe made of a lightweight aluminum alloy, the rotation of the swash plate is further stabilized. Considering that the shape of the swash plate is complicated, it is desirable that the swash plate made of an iron-based material be cast,
Therefore, it is desirable that the material be cast iron. Among the cast irons, it is desirable that the ductile cast iron has high strength and high durability, and among them, the FCD7, which has higher strength, is preferable.
More preferably, it is 00. The constituent material of the swash plate is not particularly limited, and for example, an aluminum alloy or the like can be adopted for the purpose of weight reduction and the like.

When an iron-based swash plate is used, in order to improve sliding characteristics, aluminum,
A swash plate in which a metal sprayed film made of copper or an alloy thereof is formed can be used. Further, it is also possible to use a swash plate in which the surface portion with which the shoes are in sliding contact is quenched. Even in the case of sliding contact with the swash plate in such an aspect, the shoe of the present invention having the metal plating film is less likely to cause seizure and has less wear, so that good sliding characteristics can be maintained. Therefore, the shoe of the present invention described above is a shoe suitable for such a swash plate.

(23) The swash plate compression according to item (21) or (22), wherein the swash plate has a lubricating coating formed on the surface of the sliding surface of the swash plate compressor shoe. Machine. The sliding between the swash plate and the shoe is extremely severe because the swash plate is rotated at a high speed. Therefore, the swash plate compressor according to the present paragraph, in which a lubricating film for ensuring lubrication is formed on the surface of the swash plate on which the shoe slides, friction between the swash plate and the shoe is reduced, and It becomes a swash plate type compressor that can operate smoothly.

The lubricating coating can have the same structure as the lubricating coating that can be formed on the shoe described above, for example. The lubricating coating has a relatively small strength and is easily peeled off due to scratches on the shoe. The shoes of the various aspects described above have a metal-plated coating, and when they are carried out in such a manner that they slide on the swash plate at the location where this thick film is formed, the occurrence of scratches on the shoe is suppressed at that location. Therefore, the lubricating film formed on the surface of the swash plate is less likely to be damaged, and the swash plate compressor can maintain good sliding characteristics for a long period of time.

(24) Equipped with a discharge volume changing mechanism for changing the discharge volume by changing the inclination angle of the swash plate (21)
The swash plate compressor according to items (23). In the case of a variable capacity swash plate compressor that can change the discharge capacity,
By changing the inclination angle of the swash plate, it is common to change the reciprocating stroke of the piston and change the discharge capacity. In the case of such a swash plate compressor in which the swash plate tilt angle can be changed, as the tilt angle of the swash plate with respect to the rotation axis increases, that is, the more the swash plate is in the lying state, the shoes on the side surface of the swash plate are increased. The major axis of the orbital ellipse becomes longer. The swash plate compressor is often pursued to be compact, and is made small enough not to interfere with the piston when the swash plate is not tilted. That is, for example, the swash plate is often designed so that the shoe has a diameter that does not just stick out from the inside of the side surface of the swash plate when it is not tilted. Therefore, in a swash plate compressor having such a swash plate, when the angle of inclination is large, when the shoe slides near the major axis of the elliptical orbit, that is, when the piston is near top dead center and bottom dead center, Part of the shoe may stick out of the outer circumference of the swash plate and make sliding contact therewith. In such a case, the contact area between the shoe and the swash plate is reduced, and a large pressing force is applied to the narrow area.
Further, since centrifugal force is applied to the shoe, the shoe may be inclined and slidably contact with the swash plate. At that time, a large pressing force is applied to an extremely narrow area of the outer peripheral end of the swash plate. Therefore, in the case of the swash plate type compressor having a variable capacity, there are more severe conditions for the shoes. Further, when the lubricating coating is formed on the sliding contact surface of the swash plate, the strength of the lubricating coating is relatively small. Therefore, when the shoe slides in a small area, the lubricating coating is abraded. Also in this point, the sliding condition between the shoe and the swash plate is severe in the variable capacity swash plate compressor. In the swash plate type compressor of the present invention, by adopting the shoe on which the metal plating film is formed, the sliding characteristics are ensured in a good state. In other words, the shoe of the present invention is particularly suitable for a swash plate compressor in which the tilt angle of the swash plate is changed, such as a variable capacity swash plate compressor.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, as one embodiment of the present invention, a swash plate type compressor used for an air conditioner for a vehicle and a swash plate type compressor shoe as a component thereof will be taken as an example and based on the drawings. I will explain it in detail.

FIG. 1 shows a swash plate compressor according to this embodiment. In FIG. 1, 10 is a cylinder block,
On one circle around the central axis of the cylinder block 10,
A plurality of cylinder bores 12 extending in the axial direction are formed. Each of the cylinder bores 12 has a single-headed piston 14
A piston 14 (hereinafter abbreviated as a piston) is arranged so as to be capable of reciprocating movement. The front housing 16 is attached to one axial end surface of the cylinder block 10 (the left end surface in FIG. 1, which is referred to as the front end surface), and the other end surface (the right end surface in FIG. 1 and the rear end surface). The rear housing 18 is attached via a valve plate 20. Front housing 16, rear housing 1
The housing of the swash plate compressor is constituted by 8, the cylinder block 10 and the like. A suction chamber 22 and a discharge chamber 24 are formed between the rear housing 18 and the valve plate 20, and are connected to a refrigeration circuit (not shown) via a suction port 26 and a supply port 28, respectively. The valve plate 20 includes a suction hole 32, a suction valve 34, and a discharge hole 3.
6, a discharge valve 38 and the like are provided.

A rotary shaft 50 is provided in the housing so as to be rotatable about the central axis of the cylinder block 10. The rotary shaft 50 is rotatably supported at its both ends by the front housing 16 and the cylinder block 10 via bearings.
A support hole 56 is formed at the center of the cylinder block 10, and the support hole 56 is supported through the bearing in the support hole 56. An end of the rotary shaft 50 on the front housing 16 side is connected to a vehicle engine as a drive source (not shown) via a clutch device such as an electromagnetic clutch. Therefore, when the rotating shaft 50 is connected to the vehicle engine by the clutch device during operation of the vehicle engine, the rotating shaft 50 is rotated about its own axis.

A swash plate 60 is attached to the rotary shaft 50 so as to be movable in the axial direction and tiltable. Swash plate 60
Has a through hole 61 passing through the center line, and the rotary shaft 50 passes through the through hole 61. The through hole 61 has a gradually increasing inner dimension in the up-down direction in FIG. 1 on the opening side of both ends, and the cross-sectional shape of these both ends is a long hole. A rotary plate 62 is fixed to the rotary shaft 50 and is received by the front housing 16 via a thrust bearing 64. The swash plate 60 has a hinge mechanism 66,
It is allowed to rotate integrally with the rotary shaft 50 and is allowed to tilt with movement in the axial direction. The hinge mechanism 66 includes a support arm 67 fixedly provided on the rotating plate 62 and a swash plate 6.
0 fixedly provided with a guide hole 68 of the support arm 67.
The guide pin 69 slidably fitted to the swash plate 6
0 through hole 61 and the outer peripheral surface of the rotary shaft 50 are included.

The piston 14 is provided with an engaging portion 70 engaged with the outer peripheral portion of the swash plate 60, and the head portion 7 integrally provided with the engaging portion 70 and fitted into the cylinder bore 12.
2 and. The head 72 in the present embodiment is a hollow head to reduce the weight. The head 72, the cylinder bore 12, and the valve plate 20 cooperate to form a compression chamber. Further, the engagement portion 70 is engaged with the outer peripheral portion of the swash plate 60 via a pair of spherical crown shoes 76. The shoe 76 will be described in detail later.

The rotational movement of the swash plate 60 is converted into the reciprocating linear movement of the piston 14 via the shoe 76. In the intake stroke in which the piston 14 moves from top dead center to bottom dead center,
The refrigerant gas in the suction chamber 22 is sucked into the suction hole 32 and the suction valve 34.
And is sucked into the compression chamber in the cylinder bore 12. In the compression stroke in which the piston 14 moves from the bottom dead center to the top dead center, the refrigerant gas in the compression chamber inside the cylinder bore 12 is compressed and discharged into the discharge chamber 24 through the discharge hole 36 and the discharge valve 38. With the compression of the refrigerant gas, the piston 14
An axial compression reaction force acts. The compression reaction force is the piston 1
4, swash plate 60, rotary plate 62 and thrust bearing 6
It is received by the front housing 16 via 4.

An air supply passage 80 is provided through the cylinder block 10. The air supply passage 80 connects the discharge chamber 24 and the swash plate chamber 86 formed between the front housing 16 and the cylinder block 10. An electromagnetic control valve 90 is provided in the middle of the air supply passage 80. The current supply to the solenoid 92 of the electromagnetic control valve 90 is controlled by a control device (not shown) mainly composed of a computer according to information such as a cooling load.

A discharge passage 100 is provided inside the rotary shaft 50. The discharge passage 100 has one end opened to the support hole 56 and the other end opened to the swash plate chamber 86. The support hole 56 is communicated with the suction chamber 22 via the discharge port 104.

The swash plate type compressor is a variable displacement type, and the pressure inside the swash plate chamber 86 is controlled by utilizing the pressure difference between the discharge chamber 24 on the high pressure side and the suction chamber 22 on the low pressure side. , The difference between the pressure of the compression chamber in the cylinder bore 12 acting before and after the piston 14 and the pressure of the swash plate chamber 86 is adjusted,
The inclination angle of the swash plate 60 is changed, the stroke of the piston 14 is changed, and the discharge capacity of the compressor is adjusted. Specifically, the pressure in the swash plate chamber 86 is controlled by controlling the excitation and demagnetization of the electromagnetic control valve 90 so that the swash plate chamber 86 is communicated with or cut off from the discharge chamber 24.
That is, the discharge capacity changing mechanism in the swash plate compressor according to the present embodiment includes the above-described hinge mechanism 66, the cylinder bore 12, the piston 14, the suction chamber 22, and the discharge chamber 2.
4, a support hole 56, a swash plate chamber 86, a discharge passage 100, a discharge port 104, a control device (not shown), and the like.

Cylinder block 10 and piston 14
Is made of an aluminum alloy, which is a kind of metal, and the outer peripheral surface of the piston 14 is coated with a fluororesin. By coating with a fluororesin, direct contact with the same kind of metal can be avoided, seizure can be prevented, and the fitting gap with the cylinder bore 12 can be made as small as possible. However, the material of the cylinder block 10 and the piston 14, the material of the coating layer, and the like are not limited to the above materials and the like, and other materials and the like may be used.

The engaging portion 70 of the piston 14 is generally U-shaped, and has a pair of arms 120 and 122 extending in parallel to each other in a direction orthogonal to the central axis of the head 72, and the bases of the arms 120 and 122. Connection part 1 that connects the ends together
24 and. Concave spherical surfaces 128, which serve as shoe holding surfaces, are formed on the side surfaces of the arm portions 120 and 122 that face each other. These two concave spherical surfaces 128 are located on the same spherical surface.

As shown in FIG. 2, the pair of shoes 76 has a spherical surface portion 132 whose one outer surface is a generally convex spherical surface.
And the other has a flat portion 138 that is generally flat, and is spherical. Strictly speaking, the flat surface portion 138 is a slightly curved surface having a medium height (for example, a convex spherical surface having an extremely large radius of curvature), and the outer peripheral portion is a tapered surface having an extremely large taper value. Further, the portion of the spherical surface portion 132 on the side closer to the flat surface portion 138 is a cylindrical surface. The boundaries of these medium-high curved surfaces, tapered surfaces, cylindrical surfaces, convex spherical surfaces, etc. are rounded with a relatively small radius of curvature. The pair of shoes 76 has a concave spherical surface 1 of the piston 14 in the spherical surface portion 132.
The slidable plate 28 is slidably held in contact with both sliding surfaces 140 and 142 which are both side surfaces of the outer peripheral portion of the swash plate 60 at the flat portion 138, and holds the outer peripheral portion of the swash plate 60 from both sides. In other words, in the shoe 76, the flat surface portion 138 slides on the swash plate 60, and the spherical surface portion 132 slides on the piston 14. In this state, the pair of shoes 76 has the spherical portion 1
It is designed so that 32 convex spherical surfaces are located on the same spherical surface. That is, the shoe 76 in the present embodiment has a shape close to a spherical crown that is smaller than the hemisphere by about half the thickness of the swash plate 60.

The shoe 76 includes a base material 146 and a base material 146.
148, more specifically, the metal plating film 148 that covers the entire surface
Consists of. Note that the thickness of the metal plating film 148 is exaggerated in FIG. 2 for easy understanding.

The base material 146 is mainly composed of aluminum and contains Al-S corresponding to A4032 containing silicon.
It consists of an i-based alloy. In the shoe of the present embodiment, the base material is not limited to the Al-Si alloy, but various aluminum alloys can be used. An example of the shoe manufacturing method is as follows. A round bar with a predetermined diameter is used as the material. This round bar can be obtained by extruding a billet having a predetermined shape made of an aluminum alloy having a predetermined composition obtained by casting. First, the round bar is cut into a predetermined length with a shearing device, a saw, etc., and then cold forging is performed with a pressing device equipped with a predetermined die, so that the cut material is cut into a rough shape. It is made by molding into even one. The manufacturing method of the shoe of the present embodiment is not particularly limited, and the shoe may be manufactured not by cold forging but by another already known general method. For example, it can be manufactured by hot forging, casting, punching with a press, machining, or a combination thereof. Then, a predetermined heat treatment can be applied to the shoe formed into a rough shape. The heat treatment is
After performing the solution treatment, the artificial age hardening treatment is performed, and a heat treatment generally called T6 treatment can be performed. The T6 treated shoe has extremely high strength and hardness. Note that processing other than T6 processing, such as T7 processing, may be performed. After the heat treatment, grinding or the like is performed to form the shoe into the predetermined shoe shape (strictly, the predetermined base material shape), and the shoe forming is completed. By having the aluminum alloy base material 146, the swash plate compressor becomes a lightweight swash plate compressor.

The metal plating film 148 formed on the surface of the shoe 76 may have any of the forms listed in the above-mentioned [Problems to be solved by the invention, problem solving means and effects]. The characteristics of the respective types of metal plating coatings are the same as the above description, and are therefore omitted here. Regarding each plating method, as mentioned above,
It may be performed by an appropriate method including a known method. Here, when each metal plating film constitutes the metal plating film 148 of the shoe 76 as a single layer, an appropriate composition range and a film thickness are shown. The following [Table 1] shows the composition range of various plating films in the case of electroless plating film, and the following [Table 2] shows the composition range of various plating films in the case of electroplating film. And
As for the thickness of each plating film, the lower limit for obtaining a substantial effect is 10 μm, the preferable lower limit for obtaining a higher effect is 20 μm, no adverse effect due to being too thick occurs, or in terms of cost, etc. The preferable upper limit is 150 μm, and the more preferable upper limit is 100 μm. In addition, in [Table 1] and [Table 2], "lower limit 1" is
A suitable lower limit range for substantially obtaining the effect of the contained components or the effect of applying the metal plating film, “lower limit 2” means a more preferable lower limit range at which a higher effect is obtained, The "upper limit 2" means that the adverse effect of the contained components or the adverse effect of the plating film being too thick does not occur, or the preferable upper limit range considered to be practical from the viewpoint of cost etc. is the "upper limit 1".
Means a more preferable upper limit range. Further, in the composition, "-" means that it is a main component and the balance is composed. The compositions in [Table 1] and [Table 2] are represented by weight% when the total amount of the electroplated coating is 100% by weight.

[0048]

[Table 1]

[0049]

[Table 2]

Further, as described above, when the electroless plating film is adopted, it can be a plating film in which PTFE is co-deposited. In this case, in order to obtain a substantial addition effect, the PTFE is 100% over the entire electroless plating film.
When it is set to the weight percent, it is desirable to contain it in a proportion of 0.5 weight percent or more, and it is more desirable to be 0.7 weight percent or more from the viewpoint of higher addition effect. Considering that the strength of the coating film itself is excessively lowered, it is preferably 12% by weight or less for practical use, and more preferably 10% by weight or less for more practical use.

Further, as described above, when the electroless plating film is adopted, Sn, TiCN, Ti is formed on the surface thereof.
It is also possible to use the metal plating film 148 in which the film containing at least one of N, CrN and TiAlN is formed. In this case, regarding the film thickness when each film alone is formed, the lower limit at which a substantial effect can be obtained is 0.1 μm, the preferable lower limit at which a higher effect is obtained is 0.5 μm, and an adverse effect due to being too thick Does not occur, or in terms of cost, the upper limit is preferably 5 μm, and the more preferable upper limit is 4 μm.

Furthermore, as described above, the metal plating film may contain SiC, Si ₃ N ₄ , Al ₂ O ₃ and CrC. In this aspect, the proper content ratio when each of them is contained alone is 0.5% by weight, and the higher effect is the lower limit when the metal plating film is 100% by weight. The preferred lower limit for obtaining is 1% by weight, no adverse effect occurs,
Or, from the viewpoint of cost, etc., the preferable upper limit is 20% by weight, and the more preferable upper limit is 15% by weight.

Next, the structure of the swash plate 60 will be described.
The base material 160 of the swash plate 60 on which the shoes 76 slide is made of ductile cast iron (FCD700). Sliding surface 140
An aluminum sprayed film 162, which is a metal sprayed film, is formed on the surface of the base material 160, and a lubricating coating 164 is further formed on the surface of the base material 160 (the same applies to the sliding surface 142 facing back). Has been done. In FIG. 2, the thickness of the aluminum sprayed film 162 and the thickness of the lubricating coating 164 are
Exaggerated for ease of understanding. Lubrication film 164 is made of synthetic resin polyamide imide and MoS ₂
And graphite dispersed therein, and having a thickness of 60 μm, it is possible to sufficiently reduce friction during sliding. The aluminum sprayed film 162 has a thickness of 60 μm, and even when the lubricant film 164 is removed due to wear, peeling, or the like due to some factor, the base material 160 is prevented from directly slidingly contacting, It functions to maintain good sliding characteristics.

In this embodiment, the various characteristics of the shoe 76, the swash plate 60, etc. described above are comprehensively exhibited, and as a result, the swash plate compressor has good sliding characteristics and operates smoothly. The swash plate compressor has excellent durability and can maintain its good sliding characteristics for a long period of time. In particular, the presence of the metal plating film 148 formed on the surface of the shoe 76 greatly contributes to the improvement of sliding characteristics.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, it is also possible to apply to a swash plate type compressor provided with a double-headed piston having heads on both sides of an engaging portion with a swash plate, or a fixed capacity type swash plate type compressor, etc.
The present invention is implemented in a form in which various modifications and improvements are made on the basis of the knowledge of those skilled in the art, including the embodiments described in the above-mentioned [Problems to be solved by the invention, problem solving means and effects]. be able to.

[0056]

EXAMPLE A swash plate compressor shoe having various metal plating films formed thereon was manufactured based on the above embodiment. A seizure resistance test using a test device was performed on these shoes, and a dry lock test was performed on some of them in an actual machine to investigate the sliding characteristics. These will be described below.

<Manufactured shoe> A equivalent to A4032
Formed by cold forging from 1-Si alloy material,
After performing 6 processing, grinding processing was performed and the base material of the shoe was produced. Various metal plating films were formed on the surface of this shoe base material, and the surface was conditioned by buffing to manufacture a shoe. Fifteen types of shoes were manufactured depending on the type of metal plating film formed. Each shoe was numbered # 1 to # 15. # 1 to # 8 have a coating formed by electroless plating, and # 9 to # 15 have
A film formed by electroplating is formed. The following [Table 3] shows the composition of each metal plating film for each shoe (each composition component is represented by weight%), the film thickness, and the hardness. The # 1 shoe was obtained by co-depositing PTFE on Ni-P based electroless nickel plating, and the # 3 to # 7 shoes were Ni-P-B-W based electroless nickel. Sn, TiCN, and
A metal plating film is formed by forming a film of TiN, CrN, or TiAlN. In these shoes # 3 to # 7, the total film thickness is taken as the film thickness of the metal plating film, and the film hardness is the hardness of the Ni-P-B-W type electroless nickel film. In the remarks column of [Table 3], the content ratio of PTFE in the metal plating film is
In addition, Sn, TiC in the film thickness of the metal plating film
The respective film thicknesses of the N, TiN, CrN, and TiAlN coatings are described.

[0058]

[Table 3]

<Seizure resistance test> A seizure resistance test was performed on the manufactured shoes # 1 to # 15. Figure 3 shows the seizure resistance test.
As shown in FIG.
Each shoe 76 was pressed against the sliding surface of 0 with a predetermined load, and the swash plate 60 was rotated in that state to measure the time until seizure occurred. The swash plate 60 is the same as that described in the above [Embodiment of the Invention],
It consists of FCD700, and on the sliding surface, as described above,
An aluminum sprayed film and a lubricating film are formed. A load is applied so that the pressing force is 8.5 N / mm ² (value obtained by dividing the pressing load by the area of the flat surface of the shoe), and the peripheral speed of the swash plate 60 is 10.5 m on the sliding surface. / S. In addition, the lubrication condition is a non-lubrication condition, that is, a severe condition that no lubricating oil is supplied. As a result of this test, Table 4 below shows the time required for seizure of each shoe. It can be confirmed that all of the shoes # 1 to # 15 are shoes excellent in seizure resistance because it takes a considerably long time before seizure occurs. Therefore, it can be said that each shoe is a shoe having excellent sliding characteristics.

[0060]

[Table 4]

<Actual Dry-Lock Test> # 1 to # 15
Typical shoes # 1, # 2, # 8, #
Choose shoes # 11, # 13 and # 15 and run them
It was subjected to a dry rock test. The actual machine used is
Variable embodiment swash plate type compression described in the section
The description is omitted because it is the same as the machine. Each
The condition that there is no refrigerant (dry condition)
Conditions), that is, under the severe condition of no lubrication
To measure the time until dry lock occurs.
Decided The rotation speed of the swash plate is 1000 rpm (on the sliding surface
(Corresponding to a peripheral speed of about 4.2 m / s). In addition,
The pressure that the shoe receives from the swash plate
Value divided by the area of the plane part) is the largest
About 6.8 N / mm at the shoe ²Becomes This test
As a result, each shoe is placed in the following [Table 5].
The time to dry lock when installed is shown.

[0062]

[Table 5]

As can be seen from the above [Table 5], it takes 20 seconds or more to dry-lock regardless of which shoe is provided. Due to the structure of the swash plate type compressor, the shoes are lubricated by the lubricating oil mixed in the refrigerant. Since the refrigerant liquefies and accumulates in the compressor when the operation is stopped, the shoe lubrication condition is close to the non-lubrication condition.
It takes about 2 minutes from the start of operation until the refrigerant circulates.
Since it takes 0 second, the unlubricated state continues during that time. Even if any of the above shoes are installed, while this unlubricated condition in the actual machine continues,
It can be confirmed that dry lock does not occur. Therefore, it can be said that any of the above shoes is a shoe that can be practically used without any trouble and has excellent sliding characteristics.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a swash plate compressor including a swash plate compressor shoe according to an embodiment of the present invention.

FIG. 2 is a front cross-sectional view of a part of the swash plate compressor shoe and a swash plate that slides with the shoe.

FIG. 3 schematically shows how a seizure resistance test is performed.

[Explanation of symbols]

14: Single-headed piston 60: Swash plate 76: Shoe
132: spherical surface portion 138: flat surface portion 146: base material (of shoe) 14
8: Metal plating film 160: Base material (of swash plate) 162: Aluminum sprayed film (metal sprayed film) 164: Lubrication film

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinobu Okubo             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Inside Toyota Toyota Industries (72) Inventor Akira Onoda             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Inside Toyota Toyota Industries (72) Inventor Tomohiro Murakami             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Inside Toyota Toyota Industries (72) Inventor Minoru Yone             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Inside Toyota Toyota Industries F term (reference) 3H076 BB26 CC12 CC20 CC33

Claims (2)

[Claims] 1. A shoe disposed between a swash plate and a piston in a swash plate compressor, comprising a base material made of an aluminum alloy, and a metal plating film covering at least a part of the surface of the base material. And the metal plating film includes an electroless plating film containing at least one of Ni and Co as a main constituent element, Ni, Fe,
A shoe for a swash plate type compressor, comprising at least one of an electroplated coating containing at least one of Cr and Co as a main constituent element. 2. A swash plate compressor comprising a swash plate and a piston, and the shoe for the swash plate compressor according to claim 1 disposed between the swash plate and the piston. .