KR20010020815A - A compressor of capacity fixed type with one side slant plate mode - Google Patents

Abstract

PURPOSE: To suppress a neck part of a piston to deform by bending force of inertia force, and improve durability by forming each spherical seat surface in a single spherical shape, in a device wherein a pair of spherical seat surfaces are recessed on front and rear sides of a single head piston housed in a cylinder bore freely to perform reciprocating motion. CONSTITUTION: A piston 6 is provided with a pair of spherical seat surfaces 6a, 6b which are recessed face to face in front and rear directions on a driving shaft side of a neck part 6c. In this case, the spherical seat surfaces 6a, 6b are formed in a single sphere B shape around a point O. The point O is disposed in a center surface P of a swash plate 7. The piston 6 is also provided with a head 6e having a hollow part 6d for performing compressing action in a cylinder bore. A shoe is provided with a spherical surface 8a slidably housed in the spherical seat surfaces 6a, 6b, and an end surface 8c slide with the swash plate 7 facing to the spherical surface 8a. The neck part 6c of the piston 6 is shortened in an axial direction, and deformation of the neck part 6c caused by bending force of inertia force is suppressed.

Description

Capacity Fixed Single Sided Plate Compressor {A COMPRESSOR OF CAPACITY FIXED TYPE WITH ONE SIDE SLANT PLATE MODE}

The present invention relates to a capacity fixed type single side plate type compressor. A refrigeration circuit used in a vehicle air conditioning system has a compressor for compressing refrigerant gas. In addition to the fixed capacity type, this compressor has a variable capacity type. In more detail, in the fixed capacity compressor, in addition to the one-sided swash plate type, there are a double headed swash plate type and the like. In addition to the one-sided swash plate type, the variable displacement compressor includes a double-headed swash plate type.

Among these compressors, the capacitively fixed single-sided plate type includes cylinder bores, crank chambers, suction chambers, and discharge chambers formed inside the housing, and within each cylinder bore, a single head piston is reciprocally housed. In addition, the drive shaft supported to rotate in the housing is driven by an external drive source such as an engine, and the swash plate is supported to synchronously rotate with a certain inclination angle with respect to the drive shaft. A shoe for moving is provided. Here, the piston has a pair of spherical surfaces that are concavely installed back and forth, and the shoe is composed of a spherical surface which is slidably accommodated on the spherical surface, and a cross section which faces the spherical surface and slides with the swash plate.

In such a capacity fixed type single side swash plate compressor, when the drive shaft is driven by an external drive source, the swash plate reciprocates in the cylinder bore through the shoe as the swash plate rotates synchronously with a constant inclination angle. As a result, the cylinder bore forms a compression chamber between the head of the piston. When the compression chamber is a suction stroke, low pressure refrigerant gas is sucked into the compression chamber from the suction chamber connected to the evaporator of the refrigerating circuit. When the chamber is in a compression stroke, high-pressure refrigerant gas is discharged from the compression chamber into the discharge chamber. This discharge chamber is connected to the condenser of the refrigerating circuit, and the refrigerating circuit is provided to the air conditioning of the vehicle as the vehicle air conditioning system. In this process, in this fixed capacity single-sided swash plate type compressor, sliding motion between the spherical surface of the piston and the shoe spherical surface is ensured by the misty lubricant contained in the refrigerant gas.

By the way, in the conventional capacity fixed type single side swash plate type compressor, each sphere seat which forms a piston pair is independent in hemispherical shape, and does not have a single sphere shape. For this reason, in this compressor, the neck part which forms the seat surface of a piston is easy to deform | transform, and there exists a possibility that durability may deteriorate, for example, it may interfere with reciprocating motion of a piston.

That is, if the compressor is of a double headed swash plate type, for example it is fixed capacity, variable capacity or the piston of the compressor is a double head piston having heads on both sides. Such a piston reciprocates in a cylinder bore in which both heads face each other. Here, the inertial force (W) acting in the front-rear direction of each piston is M as the mass of the piston, S as the stroke of the piston, ω (rad) as the speed per time t (sec) of the drive shaft, and N as the rotation speed of the drive shaft. rpm), W = M · S / 2 · sin ² ωt = M · S / 2 · sin ² (2π · N / 60). This inertial force W acts on the neck of the piston as a force in the bending direction. However, in such a piston, since the heads formed on both sides of the neck are supported by the cylinder bore, bending deformation of the neck does not occur. For this reason, such a piston does not interfere with a reciprocating motion even if each spherical surface does not have a single spherical shape, and there is no concern about durability.

On the other hand, if the compressor is of a one-sided swash plate type, for example it is fixed capacity, variable capacity or the piston of the compressor is a single head piston having a head only on one side. This piston has one head reciprocating in the cylinder bore. Here, also in such a compressor, said inertia force W acts on each piston as a force of a bending direction in the neck part of a piston. By the way, in a single head piston, since one side of the neck is a free end, bending of the piston tends to occur due to the inertia force W described above. Therefore, in such a compressor, as the rotation speed N increases, the inertia force W is large, the neck of the piston is easily deformed, and as a result, durability may be deteriorated. In addition, with the bending deformation of the neck, the gap between the seat surface is enlarged, the clearance between the seat surface and the shoe is increased, and noise is likely to occur.

In particular, if the one-sided swash plate type compressor is a fixed capacity type, the inclined angle of the swash plate can be changed in the capacity variable type compressor, so that the inclined angle of the swash plate is always constant, and the piston S of the piston is constant, The inertia force W acting on is always in a large state. For this reason, large inertia force W always acts on the neck part of each piston, and the neck part of a piston tends to bend.

Here, when the pair of spherical seating surfaces do not have a single spherical shape, the neck of the piston is extended in the axial direction, and the neck of the piston is more easily bent by the inertia force (W).

Moreover, when the neck of a piston becomes long, the mass M of a piston will become large. If the mass M of the piston is large, the inertia force W is also large, so that the neck of the piston is more likely to bend. In addition, increasing the mass of the piston leads to weight of the compressor.

The present invention has been made in view of the above circumstances, and an object thereof is a capacity fixed type piece that is hard to be deformed by the neck of the piston due to the force in the bending direction due to the inertia force (W) acting on the neck of the piston, and can exhibit excellent durability. It is to provide a side plate compressor.

1 is an overall longitudinal cross-sectional view of a compressor of an embodiment of the present invention.

2 is an enlarged sectional view of a main portion of a compressor of an embodiment of the present invention;

(Explanation of symbols for the main parts of the drawing)

1a. Cylinder bore 2a. Crankcase

3a. Inhalation chamber 3b. Discharge chamber

1, 2, 3. Housing (1; cylinder block, 2; front housing, 3; rear housing)

5. Drive shafts 6a, 6b. Spherical surface

6c. Neck 6d. Meat removal part (hollow part)

6e. 7. swash plate

8. Shoe 8a. Spherical surface

The capacitively fixed single-sided plate type compressor of the present invention includes a housing defining a cylinder bore, a crank chamber, a suction chamber, and a discharge chamber therein, a single head piston accommodated to reciprocate in the cylinder bore, and driven by an external driving source. And a drive shaft rotatably supported by the housing, and capable of synchronous rotation with a predetermined inclination angle with respect to the drive shaft, and a swash plate which drives the piston through a pair of shoes before and after the piston. Capacitively fixed piece having a pair of spherical seating surfaces concavely installed at the front and rear, each shoe having a spherical surface to be slidably accommodated in the respective seating surface, and a cross section facing the spherical surface for sliding with the swash plate. In the side plate compressor,

The piston is characterized in that the pair of the spherical surface is a single sphere shape.

Also in the compressor of the present invention, the inertial force W acts as a force in the bending direction on the neck of the piston because it is a one-sided swash plate type. In particular, since the compressor of the present invention is of a fixed capacity type, the neck of the piston is easily bent by the inertia force (W).

However, in the compressor of the present invention, the pair of spherical seating surfaces of the piston form a single spherical shape. For this reason, the neck of the piston is shortened in the axial direction, and the neck of the piston is less likely to bend even by the inertia force. In addition, in a piston having a pair of spherical surfaces having a single spherical shape, the axial shortening of the neck shortens the entire axial length and the total mass. As a result, the inertia force is also reduced, which makes the neck of the piston more difficult to bend.

Therefore, the capacity fixed type single side plate type compressor of the present invention can exhibit excellent durability.

It is preferable that the piston in the compressor of this invention has the flesh removal part from which the flesh was removed except the head. This is because the mass of the piston is reduced, and accordingly the inertia force is also reduced, so that the neck of the piston is more difficult to bend. In addition, when the mass of the piston is reduced, the weight of the compressor can be reduced, which contributes to the improvement of fuel efficiency of the vehicle. As the flesh removal part, for example, a hollow part formed inside the piston can be adopted. Such a hollow portion may be of a completely sealed type, communicated with the outside by a vent hole, or the like.

(Example)

EMBODIMENT OF THE INVENTION Hereinafter, the Example which actualized the capacity | capacitance fixed type side swash plate type compressor of this invention is demonstrated, referring drawings.

In this compressor, as shown in FIG. 1, the front housing 2 is coupled to the front end of the cylinder block 1, and the crank chamber 2a is formed in the cylinder block 1 and the front housing 2. As shown in FIG. The rear housing 3 is coupled to the rear end of the cylinder block 1 via a suction valve 13, a valve plate 4, a discharge valve 14, and a retainer (not shown). The suction chamber 3a is formed in the center region of the rear housing 3, and the annular discharge chamber 3b is formed in the outer peripheral region.

The suction chamber 3a is connected to the evaporator EV of the external refrigeration circuit by piping, and the evaporator EV is connected to the condenser CO through the expansion valve V by the piping. The condenser CO is again connected to the discharge chamber 3b by piping.

The drive shaft 5 is rotatably supported by the front housing 2 and the cylinder block 1 via bearing devices 2b and 1b. Five cylinder bores 1a are formed in the cylinder block 1 in parallel with the axis of the drive shaft 5, and the single head piston 6 is accommodated in each cylinder bore 1a so as to reciprocate. The swash plate 7 is fixed to the drive shaft 5 so as to be rotatable in the crank chamber 2a through the bearing device 2c between the front housing 2, and the swash plate 7 has a pair of shoes ( 8) the piston 6 is mooring.

As shown in FIG. 2, this piston 6 has paired seating surfaces 6a and 6b which are recessed so as to face in the front-rear direction on the drive shaft 5 side of the neck 6c. These spherical surface 6a, 6b is the characteristic structure of this invention, and has comprised the shape of the single sphere B centering on the point O. As shown to FIG. The point O is located in the center plane P of the swash plate 7. Moreover, the hollow part 6d as a flesh removal part is formed in this piston 6. Moreover, the piston 6 has the head 6e which is to perform the compression action in the cylinder bore 1a, and the hollow part 6d is formed in the site | part except the head 6e.

The shoe 8 is provided with a spherical surface 8a which can be slidably accommodated in the spherical surfaces 6a and 6b of the piston 6, and the swash plate 7 and the sliding motions facing the spherical surface 8a. It has a cross section 8c.

In addition, as shown in FIG. 1, the valve plate 4 is provided with a suction hole 4a and a discharge hole 4b, which communicate with each other through the cylinder bore 1a, the suction chamber 3a, and the discharge chamber 3b. have. Then, the suction hole 4a is opened and closed by the suction valve 13 corresponding to the reciprocating motion of the piston 6, and the discharge hole 4b is similarly discharge valve 14 corresponding to the reciprocating motion of the piston 6. It is to be opened and closed by.

The compressor configured as described above is assembled to the air conditioning system of the vehicle together with the evaporator EV, the expansion valve V and the condenser CO of the external refrigeration circuit. In such a compressor, when the drive shaft 5 is driven by an engine (not shown), the swash plate 7 rotates synchronously with a constant inclination angle, so that the piston 6 reciprocates in the cylinder bore 1a through the shoe 8. Exercise. Thereby, the cylinder bore 1a forms a compression chamber between the head 6e of the piston 6, and when this compression chamber is a suction stroke, it is connected to the compression chamber with the evaporator EV of the refrigerating circuit. The low pressure refrigerant gas is sucked from the suction chamber 3a, and when the compression chamber is in a compression stroke, the high pressure refrigerant gas is discharged from the compression chamber to the discharge chamber 3b. In the meantime, in this compressor, the lubricating oil of the mist state contained in the refrigerant gas ensures the sliding motion between the spherical surface 6a of the piston 6 and the spherical surface 8a of the shoe 8 and the like.

Also in such a compressor, since this is a one-sided swash plate type, the inertial force W acts on the neck 6c of the piston 6 as a force in the bending direction. In particular, since the compressor is of a fixed capacity type, the neck portion 6c of the piston 6 tends to bend due to the inertia force W thereof. However, in this compressor, since the respective spherical surfaces 6a and 6b in which the piston 6 is paired have a single spherical shape, the neck 6c of the piston 6 is shortened in the axial direction. The neck 6c of the piston 6 is hard to bend even by the inertia force W.

Therefore, in this compressor, since the piston 6 has the fully closed hollow part 6d as a flesh removal part, since the mass of the piston 6 is small and the said inertial force W is also small by this, the piston ( The neck 6c of 6) is more difficult to bend.

Therefore, this compressor can exhibit excellent durability, and since the mass of the piston 6 is small, weight reduction of a compressor can be realized and it can contribute to the improvement of fuel efficiency of a vehicle, etc.

In addition, in a variable displacement compressor having a swash plate capable of changing the inclination angle, the clearance between the piston and the shoe is kept constant even when the inclination angle of the swash plate is changed. Since it is required to achieve, a variable displacement compressor, a piston, and a shoe can be used as a common component.

As for the piston in the compressor of this invention, the pair of seating surface has a single spherical shape. For this reason, the neck of the piston becomes short in the axial direction, and the neck becomes difficult to bend even by the inertia force. In addition, the piston having a pair of spherical surfaces having a single spherical shape has a short axial length in the neck portion, resulting in a short overall shaft length and a smaller overall mass. As a result, the inertia force is also reduced, making the neck of the piston more difficult to bend.

Therefore, the capacity fixed type single side plate type compressor of the present invention exhibits excellent durability, realizes light weight of the compressor, and contributes to improved fuel efficiency of the vehicle.

Claims (3)

A housing defining a cylinder bore, a crank chamber, a suction chamber, and a discharge chamber therein, a single head piston accommodated reciprocally in the cylinder bore, and driven by an external driving source, the housing being rotatable. A supported drive shaft and a swash plate capable of synchronous rotation with a constant inclination angle with respect to the drive shaft, the swash plate for driving the piston through a pair of shoes back and forth, wherein the piston is a pair of concave recesses installed in front and rear In the capacity fixed single-sided swash plate compressor having a spherical surface, each shoe has a spherical surface which is slidably accommodated in each spherical surface, and a cross section which faces the spherical surface and slides with the swash plate. The piston has a fixed capacity single-sided plate type compressor, characterized in that the pair of the spherical surface is a single sphere shape. The method of claim 1, The piston has a capacitive fixed side-swash plate type compressor, characterized in that it has a flesh removal portion to remove the flesh except the head. The method of claim 2, The flesh removal unit is fixed capacity single-sided plate type compressor, characterized in that the hollow denier formed inside the piston.