JP2002089441A - Unilateral swash plate type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a unilateral swash plate type compressor realizing lightening of weight. SOLUTION: This unilateral swash plate type compressor is provided with a housing 1, 2, 4 formed with a cylinder bore la, a crank chamber 2a, a suction chamber 4a, and a delivery chamber 4b partitioned in the inside, a single head piston 6 received movably to reciprocate in the cylinder bore la, a drive shaft 5 driven by an external drive source to be supported rotatably to the housing 1, 2, 4, a swash plate 8 supported synchronously rotatably relating to the drive shaft 5, and a shoe 9a, 9b paired before/behind the swash plate 8 to make the piston 6 driven. The shoe 9a, 9b is mainly constituted by a resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-sided swash plate type compressor used for an air conditioning system for vehicles and the like.

[0002]

2. Description of the Related Art A refrigerating circuit used in an air conditioning system for a vehicle incorporates a compressor for compressing a refrigerant gas. The compressor includes a fixed displacement type compressor and a variable displacement type compressor. More specifically, the fixed displacement compressor includes a one-side swash plate type and a double-head swash plate type. Variable displacement compressors include one-sided swash plate type and double-headed swash plate type.

[0003] Among these compressors, a general one-sided swash plate type compressor has a cylinder bore, a crank chamber, a suction chamber, and a discharge chamber defined inside a housing, and a single-headed piston reciprocates in each cylinder bore. Housed as possible.
The drive shaft rotatably supported by the housing is driven by an external drive source such as an engine, and a swash plate is supported on the drive shaft so as to be synchronously rotatable. A pair of shoes for driving the piston are provided before and after the swash plate.

Here, since the piston is a single-headed piston having a head only at one of the front and rear sides of the swash plate, this is a one-sided swash plate type compressor. If the swash plate is provided at a constant inclination angle with respect to the drive shaft, it is a fixed displacement single-sided swash plate type compressor. Further, if a swash plate is provided so that the inclination angle can be displaced with respect to the drive shaft, and if the discharge capacity can be adjusted by displacing the inclination angle by adjusting the pressure in the crank chamber by a control valve, it is a variable displacement type one side. It is a swash plate type compressor.

In such a one-sided swash plate type compressor, when the drive shaft is driven by an external drive source, the swash plate rotates synchronously, so that the piston reciprocates in the cylinder bore via the shoe. As a result, the cylinder bore forms a compression chamber between the piston and the head of the piston. Therefore, when the compression chamber is in the suction stroke, low-pressure refrigerant gas is supplied to the compression chamber from the suction chamber connected to the evaporator of the refrigeration circuit. When the compression chamber is in the compression stroke, high-pressure refrigerant gas is discharged from the compression chamber to the discharge chamber. The discharge chamber is connected to the condenser of the refrigeration circuit, and the refrigeration circuit is used for air conditioning of the vehicle as a vehicle air conditioning system. During this time, in the one-sided swash plate compressor, the slidability of the sliding contact portion such as between the swash plate and the shoe is ensured by the mist-like lubricating oil contained in the refrigerant gas.

[0006]

However, the conventional one-sided swash plate type compressor has a disadvantage that the shoe is mainly made of an iron-based material such as SUJ2 of JIS, so that the weight is large. Such a defect is the same regardless of whether it is a fixed displacement type single-sided swash plate type compressor or a variable displacement type single-sided swash plate type compressor.

The present invention has been made in view of the above-mentioned conventional circumstances, and has as an object to solve the problem of providing a one-sided swash plate type compressor which realizes weight reduction.

[0008]

SUMMARY OF THE INVENTION A one-sided swash plate type compressor according to the present invention has a housing defining therein a cylinder bore, a crank chamber, a suction chamber, and a discharge chamber, and a single housing reciprocally housed in the cylinder bore. A head piston, a drive shaft driven by an external drive source and rotatably supported on the housing, a swash plate supported rotatably synchronously with respect to the drive shaft, and a pair before and after the swash plate None, In a one-sided swash plate type compressor provided with a shoe for driving the piston, the shoe is mainly composed of resin.

The single-sided swash plate compressor of the present invention is light in weight because the shoe is mainly made of resin.

As the resin, polyamide imide (PA
I), polyimide (PI), polyetheretherketone (PEEK), phenolic resin (PF), epoxy resin (EP), polyphenylene sulfide (PPS), or the like that has heat resistance at 130 ° C. or more Can be. In order to improve the wear resistance and to reduce the coefficient of thermal expansion, carbon fibers, glass fibers, and the like can be dispersed.

A shoe may be formed of resin in a form having open cells, and the cells may be impregnated with a lubricating oil. In this case, the slidability of the sliding contact portion between the swash plate and the shoe and between the shoe and the shoe seat of the piston can be ensured.

In the one-sided swash plate type compressor according to the present invention, the swash plate is provided so as to be tiltable with respect to the drive shaft, and the displacement is adjusted by adjusting the pressure in the crank chamber by a control valve to change the tilt angle. This is particularly effective in the case of a variable capacity type. That is, since the shoe is mainly made of resin, the inertial force of the shoe acting in the direction of increasing the tilt angle is reduced, and the high-speed controllability is improved.

The swash plate comprises a swash plate base made of a first metal,
It is preferable that the swash plate base is formed of a coating formed on front and rear surfaces of the swash plate base to improve slidability with the first metal. In this case, whether the one-sided swash plate type compressor is a fixed displacement type compressor or a variable displacement type compressor, under severe conditions, the wear of the coating formed on the front surface of the swash plate substrate is also prevented. And can exhibit excellent durability.

That is, the swash plate base is made of the first metal. As the first metal, an iron-based material (refers to an iron alloy containing the largest amount of iron and iron; hereinafter the same), a copper-based material (refers to a copper alloy containing the largest amount of copper and copper, hereinafter the same), A nickel-based material (refers to a nickel alloy containing the largest amount of nickel and nickel; hereinafter the same applies), a molybdenum-based material (refers to a molybdenum alloy including the most molybdenum and a molybdenum alloy containing the largest amount of molybdenum, hereinafter the same) have large specific gravity and strength. Excellent metal can be adopted.

The following coatings (1) to (8) can be formed on the front and rear surfaces of the swash plate substrate. That is,
(1) Thermal sprayed layer of a metal such as copper-based material, aluminum-based material (refers to aluminum and an aluminum alloy containing the largest amount of aluminum; hereinafter the same), (2) copper-based material, aluminum (3) Heat resistance at 130 ° C. or more such as polyamide imide (PAI), polyimide (PI), polyether ether ketone (PEEK), etc. Molybdenum disulfide (MoS ₂ ), graphite, tungsten disulfide (WS ₂ ), boron nitride (B
N), a coating layer in which a solid lubricant such as polytetrafluoroethylene (PTFE) is dispersed, (4) tin plating, nickel-phosphorus plating, nickel-boron plating, nickel-phosphorus-boron plating, nickel-phosphorus-plating
Plating layer of a metal capable of improving slidability such as boron-tungsten plating, nickel-phosphorus-boron-tungsten-chromium plating, hard chromium plating, etc. (5) titanium nitride (TiN), chromium nitride (CrN), titanium- An ion plating layer formed by chemical vapor deposition (CVD) or physical vapor deposition (PVD) of a material capable of improving the slidability such as aluminum-nitrite (TiAlN), and (6) a layer made of diamond-like carbon (DLC) or the like , (7) ceramic coat, and (8) alumite. When a coating is not formed on the front surface or the rear surface of the swash plate substrate, it is preferable that the front surface or the rear surface is subjected to quench hardening or the like.

In the single-sided swash plate type compressor, as shown in FIG. 3, the front shoe 9 located at the bottom dead center of the swash plate 91 is used.
An inertial force F1 based on the weight of the shoe 92a acts on the center of gravity G of the center 2a in the axial direction. For this reason, the shoe 92a
Generates a moment around the front side edge A of the swash plate 91,
The shoe 92 a is inclined at a small angle θ with respect to the front surface of the swash plate 91 due to the gap between the shoe 92 a and the shoe seat on the front side of the piston 93. As a result, the swash plate 9 is provided on the shoe 92a by the inertial force F1 from the center of gravity G and by Δ from the regular position.
A vertical reaction force F2 acting vertically on the front side edge A shifted to the outer peripheral side of the actuator 1 and a force F3 acting as a reaction force of the resultant force are exerted. That is, the shoe 92a receives the force F3 at the position B where it contacts the shoe seat on the front side of the piston 93. Since the inertial force F1 varies depending on the specific gravity of the shoe 92a and the rotation speed of the drive shaft, the normal force F2 also varies depending on the specific gravity of the shoe 92a and the rotation speed of the drive shaft. Therefore, if the shoe 92a is mainly composed of an iron-based material such as JIS SUJ2 having a large specific gravity, the shoe 9
The weight of 2a is large, and the coating on the swash plate base material is easily worn especially at the front side edge A. On the other hand, when the shoe 92a is mainly composed of a resin having a small specific gravity, the mass of the shoe 92a is small, and the coating on the swash plate base material is not easily worn.

Further, the rear shoe 92b is pressed against the swash plate 91 with a load corresponding to the rotation angle. At this time, a differential pressure based on a differential pressure between the pressure in the compression chamber and the pressure in the crank chamber is applied to the rear shoe 92b,
The inertial force based on the own weight of b is acting, and the resultant force of the differential pressure and the inertial force is the load. Although the differential pressure is not different depending on the specific gravity of the shoe 92b, the inertia force is
Since a difference occurs in the specific gravity of b, the load with which the rear shoe 92b is pressed against the swash plate 91 differs depending on the specific gravity of the shoe 92b. This load changes depending on the rotation angle, and as shown in FIG. 4, the load becomes 0 or minus (rearward) at the beginning of a certain angle range α between the top dead center T and the bottom dead center U. When the rear shoe 92b separates from the swash plate 91 and the load becomes plus (forward) at the end of the angle range α, the rear shoe 9b
2b collides with the swash plate 91. Here, the energy E at the time when the shoe 92b collides with the swash plate 91 is as follows, where m is the mass of the shoe 92b, and v is the speed of the shoe 92b.

[0018]

(Equation 1)

Therefore, the energy E varies depending on the mass of the shoe 92b.

For this reason, JIS SUJ2 with a large specific gravity
When the shoe 92b is mainly composed of an iron-based material such as the above, since the mass of the shoe 92b is large, the energy when the shoe 92b collides with the swash plate 91 is large, and the coating on the swash plate base material is easily worn. Becomes On the other hand, if the shoe 92b is mainly composed of a resin having a small specific gravity,
Since the mass of the shoe 92b is small, the energy when the shoe 92b collides with the swash plate 91 is small, and the coating on the swash plate base material is not easily worn.

Therefore, in this single-sided swash plate compressor,
More excellent durability can be exhibited.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

The variable displacement single-sided swash plate type compressor (hereinafter, simply referred to as a compressor) of the embodiment is, as shown in FIG.
A front housing 2 is coupled to the front end of the cylinder block 1, and the cylinder block 1 and the front housing 2
A crank chamber 2a is formed therein. A rear housing 4 is connected to a rear end of the cylinder block 1 via a valve mechanism 3 including a suction valve, a valve plate, a discharge valve, and a retainer. In the rear housing 4, a suction chamber 4a and a discharge chamber 4b are formed. I have. The suction chamber 4a is connected to an evaporator not shown, and the evaporator is connected to a condenser not shown via an expansion valve not shown, and the condenser is connected to the discharge chamber 4b.

A drive shaft 5 is rotatably supported on the front housing 2 and the cylinder block 1 via bearing devices 2b, 1b. The drive shaft 5 is mounted on the cylinder block 1.
A plurality of cylinder bores 1a are formed in parallel with the axis of
A single-headed piston 6 is reciprocally accommodated in each cylinder bore 1a.

A rotor 7 is fixed to the drive shaft 5 so as to be rotatable in the crank chamber 2a through a bearing device 2c between the drive shaft 5 and the front housing 2. The rotor 7 has a pair of hinge mechanisms K
The swash plate 8 is provided so as to be able to swing through. The swash plate 8 is provided with a through hole 8a, and the drive shaft 5 is inserted into the through hole 8a while allowing the swash plate 8 to swing. The swash plate 8 is provided with a pair of front and rear shoes 9a and 9b, and the piston 6 is moored to each pair of shoes 9a and 9b.

Further, the suction chamber 4 is provided in the rear housing 4.
a, a control valve 10 connected to the discharge chamber 4b and the crank chamber 2a. By adjusting the pressure in the crank chamber 2a by the control valve 10, the inclination of the swash plate 8 is displaced, so that the discharge capacity can be adjusted.

In the compressor of the above embodiment, as shown in FIG. 2, the swash plate 8 is made of a swash plate base material 18 made of an iron-based material.
a and coatings 18b and 18c made of aluminum sprayed and resin-coated on the front and rear surfaces of the swash plate base 18a. The front and rear shoes 9a and 9b are made of resin or oil-containing foamed resin. Further, the piston 6
A piston base 16a made of an aluminum-based material;
A coating 16b made of tin plating formed on a shoe seat of the piston base material 16a.

The iron-based material of the swash plate substrate 18a is S
UJ2. Aluminum spraying is a sprayed layer using an Al-Si alloy as an aluminum-based material. The resin coat is a coating layer in which MoS ₂ and graphite are dispersed in PAI. The symbol + indicates that the right coating is formed on the left coating. Also, shoe 9
The resins a and 9b are phenolic resins, and the oil-containing foamed resin is an unspecified resin containing a foaming agent. For example, the phenolic resin is foamed so as to have open cells, and molded. It is impregnated. Further, the aluminum-based material of the piston base material 16a is Al-Si
Alloys such as A4032 and ADC12.

The compressor constructed as described above is light in weight because the shoes 9a and 9b are mainly composed of a resin having a specific gravity of about 1.6.

In this compressor, the shoes 9a, 9b
Has a small energy when it collides with the swash plate 8 and the mass of the shoes 9a, 9b is small, so that the coatings 18b, 18c on the swash plate base 18a are not easily worn. For this reason, in this compressor, more excellent durability can be exhibited.

Further, in this compressor, the shoes 9a, 9
Since b is mainly made of resin, the inertial force of the shoes 9a and 9b acting in the direction of increasing the tilt angle is small, and the high-speed controllability is improved.

In the compressor in which the lubricating oil is impregnated in the shoes 9a and 9b, the sliding contact portions between the swash plate 8 and the shoes 9a and 9b and between the shoes 9a and 9b and the shoe seat of the piston 6 are formed. Easy to secure slidability.

[Brief description of the drawings]

FIG. 1 is a sectional view of a variable displacement single-sided swash plate type compressor according to an embodiment.

FIG. 2 is an enlarged sectional view of a main part of the variable displacement single-sided swash plate type compressor according to the embodiment.

FIG. 3 relates to a general variable displacement type one-sided swash plate type compressor;
It is a principal part enlarged explanatory view of a swash plate, a shoe, and a piston.

FIG. 4 relates to a general variable displacement single-sided swash plate type compressor;
It is the schematic plan view which looked at the swash plate from the axial back.

[Explanation of symbols]

1a: Cylinder bore 2a: Crank chamber 4a: Suction chamber 4b: Discharge chamber 1, 2, 4 ... Housing (1: cylinder block, 2 ...)
Front housing, 4 Rear housing) 6 Piston 5 Drive shaft 8 Swash plate 9a, 9b Shoe 10 Control valve 18a Swash plate base material 18b, 18c Coating

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshihisa Shimo 2-1-1 Toyota-cho, Kariya-shi, Aichi F-term in Toyota Industries Corporation (reference) 3H076 AA06 BB38 CC12 CC20 CC33 CC34

Claims (4)

[Claims] 1. A housing which internally defines a cylinder bore, a crank chamber, a suction chamber, and a discharge chamber, a single-headed piston reciprocally housed in the cylinder bore, and the housing driven by an external drive source. A swash plate supported rotatably on the swash plate, a swash plate supported rotatably in synchronization with the drive shaft, and a pair of shoes formed in front of and behind the swash plate to drive the piston. In the plate type compressor, the one-side swash plate type compressor is characterized in that the shoes are mainly formed of resin. 2. The single-sided swash plate compressor according to claim 1, wherein the shoe is impregnated with a lubricating oil. 3. The swash plate is provided so as to be displaceable at an angle with respect to the drive shaft, and the displacement is adjustable by adjusting the pressure in the crank chamber by a control valve to adjust the displacement. The one-sided swash plate type compressor according to claim 1 or 2. 4. A swash plate, comprising: a swash plate base made of a first metal;
The single-sided swash plate type compressor according to claim 1, 2 or 3, wherein the swash plate base material is formed on a front and rear surface of the swash plate base material and comprises a coating for improving slidability with the first metal.