KR100661360B1 - Variable displacement swash plate compressor - Google Patents

Abstract

Disclosed is a variable displacement swash plate type compressor capable of smoothly changing the inclination angle of the swash plate during initial driving of the compressor, and in particular, there is no sudden change in torque, thereby improving compressor noise and improving clutch durability. The disclosed invention has a non-linear displacement characteristic of a compression coil spring which is installed between the rotor and the swash plate to return the swash plate mounted to the drive shaft so that the inclination angle can be changed in response to the pressure change of the crank chamber to the initial position. Characterized in that configured to. The compression coil spring has a section arranged at a first pitch interval P1 and a section arranged at a second pitch interval P2 larger than the first pitch interval P1, so that the elastic modulus in each section is different from each other. It may be configured, and may also be configured to gradually increase the spring diameter from the swash plate side toward the rotor side. According to this, since the elastic modulus in each section of the compression coil spring is different, the displacement advances rapidly at the inclination angle displacement of the swash plate and gradually progresses to the maximum inclination angle. Therefore, the inclination angle of the swash plate is easily increased initially so that the compression operation can be smoothly performed, and the time and speed of reaching the maximum inclination angle can be delayed to reduce the shock mitigation and the rapid fluctuation of the torque.

Compressor, swash plate compressor, variable displacement swash plate compressor, spring,

Description

VARIABLE CAPACITY SWASH PLATE TYPE COMPRESSOR

1 is a cross-sectional view showing the structure of a conventional variable displacement swash plate compressor,

2 is a cross-sectional view showing the structure of a variable displacement swash plate compressor according to the present invention;

3 is a detailed view showing an example of a spring which is a main part of the present invention;

Figure 4 is a graph showing the displacement diagram for the spring of Figure 3 compared with the conventional case,

5 is a detailed view showing another example of a spring which is a main part of the present invention, and

FIG. 6 is a graph illustrating a displacement diagram of the spring of FIG. 5 in comparison with a conventional case.

Explanation of symbols on the main parts of the drawings

5; drive shaft 6; rotor

8; swash plate 12; compression coil spring

The present invention relates to, for example, a swash plate compressor used for circulation of a refrigerant in an automobile air conditioner, and more particularly, to a variable displacement swash plate compressor capable of variably adjusting the amount of discharge refrigerant according to a load of an air conditioner.

In the swash plate type compressor, which is widely used as a compressor of an automobile air conditioner, a disk-shaped swash plate which is inclined to a driving shaft receiving engine power is rotated by a drive shaft, and the swash plate rotates through a shoe along the circumference of the swash plate. A plurality of installed pistons are configured to suck / compress and discharge the refrigerant by linearly reciprocating the inside of the plurality of cylinder bores formed in the cylinder block.

The variable displacement swash plate compressor is configured such that the inclination angle of the swash plate installed on the drive shaft is variable according to the heat load. Accordingly, the refrigerant discharge amount is variably adjusted while the reciprocating feed amount of the piston is changed.

A typical example of such a variable displacement swash plate compressor is shown in FIG. 1, which is briefly described as follows.

As shown, the variable displacement swash plate compressor includes a cylinder block 1 having a plurality of axial cylinder bores 1a therein, and a crank chamber mounted in front of the cylinder block 1 and sealed therein. Front housing 2 forming 2a) and rear housing 4 mounted on the rear of the cylinder block 1 via the valve plate 3 and having a refrigerant suction chamber 4a and a discharge chamber 4b. And a drive shaft 5 rotatably supported on the cylinder block 1 and the front housing 2, and a rotor 6 firmly mounted on the drive shaft 5 inside the crank chamber 2a. And a swash plate 8 connected to the rotor 6 by a hinge mechanism 7 mounted on the drive shaft 5 so that the inclination angle can be changed in response to the pressure change of the crank chamber 2a. The refrigerant is connected to the outer circumference of the swash plate 8 via the shoe 9 and reciprocates in the cylinder bore 1a according to the rotational rocking motion of the swash plate 8. A plurality of pistons 10 to be compressed and a displacement force regulating valve for varying the pressure difference between the refrigerant suction pressure in the cylinder bore 1a and the gas pressure in the crank chamber 2a so that the inclination angle of the swash plate 8 varies according to the heat load. 11) and a compression coil spring 12, etc., which is installed between the rotor 6 and the swash plate 8 to return to the initial position of the swash plate 8, and the like.

In the variable displacement swash plate type compressor configured as described above, when the drive shaft 5 rotates with the power of the engine, the swash plate 8 mounted on the drive shaft 5 so as to be capable of adjusting the inclination angle rotates together with the drive shaft 5. Direction of the swash plate 8, so that a plurality of pistons 10 connected to the outer circumference of the swash plate 8 reciprocate in the cylinder bore 1a of the cylinder block 1 by a distance proportional to the inclination angle of the swash plate 8 Done. As a result, the volume of the compression chamber in the cylinder bore 1a changes, and the suction, compression, and discharge of the refrigerant gas proceed in order by the volume change, and the high-pressure refrigerant gas having the capacity according to the inclination angle of the swash plate 8 is discharged. do. At this time, the inclination angle of the swash plate 8 is varied in response to the pressure difference between the pressure in the crank chamber 2a by the displacement control valve 11 and the suction pressure in the cylinder bore 1a, thereby changing the amount of discharged refrigerant.

On the other hand, the swash plate 8 is supported so as to be perpendicular to the drive shaft 5 as shown in the drawing so as to maintain a minimum inclination angle by the compression coil spring 12 when the compressor is stopped. When the compressor is driven in this state, the swash plate 8 is displaced to the required maximum inclination angle while overcoming the elasticity of the compression coil spring 12, and a compression action is performed. At this time, the compression coil spring 12 has a constant modulus of elasticity, and when the inclination angle of the swash plate 8 increases or decreases, a force proportional to the displacement of the spring is transmitted to the swash plate inclination angle displacement so that the inclination angle of the swash plate is increased. maintain.

However, in the conventional variable displacement swash plate type compressor as described above, since the compression coil spring 12 exhibits a linear displacement characteristic by having a constant elastic modulus, for example, the inclination angle of the swash plate in the free state is the minimum inclination angle. When supported to maintain the swash plate, the swash plate can move rapidly from the inclined angle of the minimum state to the inclined angle of the maximum state during the sudden clutch on / off operation, thereby increasing the compression load, not only generates clutch slip and noise, but also the swash plate It can be damaged by hitting the maximum inclined angle support surface strongly. On the other hand, when increasing the elastic modulus of the spring in order to prevent the above problems, the displacement movement up to the maximum inclination angle of the swash plate is too slow or does not work, the compression movement of the compressor does not occur Can be.

The present invention has been made in view of the above-described conventional problems, the initial swash plate inclination angle displacement is made quickly and smoothly, and since the displacement time and speed is delayed until the maximum inclination angle displacement time, the clutch with smooth compression action It is an object of the present invention to provide a variable displacement swash plate compressor that can reduce the sudden fluctuation of the torque transmitted to the engine.

The variable displacement swash plate compressor according to the present invention for achieving the above object, the rotor and the swash plate in order to return to the initial position the swash plate mounted to the drive shaft so that the inclination angle can be changed in response to the pressure change of the crankcase Compression coil springs piled in between are configured to have a non-linear displacement characteristic.

The compression coil spring has a section arranged at a first pitch interval P1 and a section arranged at a second pitch interval P2 larger than the first pitch interval P1, so that the elastic modulus in each section is different from each other. It may be configured, and may also be configured to gradually increase the spring diameter from the swash plate side toward the rotor side.

According to this, since the elastic modulus in each section of the compression coil spring is different, the displacement advances rapidly at the inclination angle displacement of the swash plate and gradually progresses to the maximum inclination angle. Therefore, the inclination angle of the swash plate is easily increased in the early stage, so that the compression operation can be smoothly performed, and the time and speed of reaching the maximum inclination angle can be delayed to alleviate the impact at the maximum inclination angle support surface of the swash plate, and Sudden fluctuations can be reduced, which can reduce the noise of the compressor and improve the durability of the clutch.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a cross-sectional view showing a variable displacement swash plate compressor according to an embodiment of the present invention, Figure 3 is a detailed view showing the structure of a compression coil spring of the main configuration of the present invention shown in Figure 2, Figure 4 is Is a graph showing a displacement diagram of a spring in comparison with the conventional case. For reference, in describing the present embodiment, the same reference numerals refer to the same parts as those in the related art.

As shown in Figure 2, the variable displacement swash plate compressor according to an embodiment of the present invention, the cylinder block (1) having a plurality of axial cylinder bores (1a) therein, and of the cylinder block (1) A front housing (2) mounted at the front to form a crank chamber (2a) sealed inside, and mounted to the rear of the cylinder block (1) through the valve plate (3), the refrigerant suction chamber (4a) and discharge A rear housing 4 having a seal 4b, a drive shaft 5 rotatably supported on the cylinder block 1 and the front housing 2, and the drive shaft 5 inside the crank chamber 2a; The drive shaft 5 which is firmly mounted on the rotor 6 and the hinge mechanism 7 connected to the rotor 6 so that the inclination angle can be changed in response to the pressure change of the crank chamber 2a. The swash plate 8 mounted on the upper surface of the swash plate 8 is connected to the outer periphery of the swash plate 8 via the shoe 9, and the cylinder A plurality of pistons 10 compressing the refrigerant while reciprocating in the gear 1a, and the refrigerant suction pressure in the cylinder bore 1a and the gas pressure in the crank chamber 2a so that the inclination angle of the swash plate 8 varies according to the heat load. A pressure control valve 11 for varying the differential pressure between the compressor and the compression coil spring 12 installed between the rotor 6 and the swash plate 8 so as to return to the initial position of the swash plate 8; It is configured to include.

As shown in FIG. 3, the compression coil spring 12 has a section arranged at a first pitch interval P1 and a second pitch interval P2 larger than the pitch interval P1 of the section. It is partitioned into sections arranged in the elastic modulus of the two side sections are configured differently. That is, the elastic modulus is small in the section where the pitch interval is small, and the elastic modulus is large in the section where the pitch interval is large. Therefore, as shown in Figure 4, the compression coil spring according to the present invention has a non-linear displacement characteristics. The dotted line in the graph of Figure 4 shows the displacement characteristics of the conventional spring.

In the compressor configured as described above, the coil spring 12 has a section (elastic coefficient section) arranged at the first pitch interval on the swash plate 8 side and a section (elastic coefficient) arranged at the second pitch interval. The large section) is interposed between the rotor 6 and the swash plate 8 so as to be positioned on the rotor 6 side to support the swash plate 8 elastically to maintain the initial position of the swash plate.

In this case, as described above, as the compressor is driven, the swash plate 8 starts the inclination angle displacement motion while overcoming the elasticity of the spring 12. The spring from the initial displacement, that is, from the minimum inclination angle to the approximately intermediate inclination angle displacement point The elastic modulus of is displaced very quickly by the section. Thus, a smooth compression can be achieved. However, from the intermediate inclination angle to the maximum inclination angle displacement point, the spring is gradually displaced by a section having a large elastic modulus. That is, by delaying the displacement time and speed in this portion, it is possible to reduce the rapid fluctuation of the torque transmitted to the engine due to the sudden inclination angle displacement of the spring as in the prior art. In addition, the impact caused by the swash plate hitting the maximum inclination angle support surface can also be alleviated.

On the other hand, the compression coil spring 12 according to the present invention having the non-linear displacement characteristics as described above, as shown in Figure 5, from one side of the spring, such as the swash plate 8 contact to the other side, for example the rotor 6 contact portion It can also be comprised by forming a spring mirror larger and larger toward.                     

In the case of the compressed coil spring according to another embodiment of the present invention as shown in Figure 6, as a result of the experiment, it can be seen that it has a non-linear displacement characteristics unlike the conventional. Therefore, in the case of such a spring, as in the spring of the variable pitch type as described above, when the inclination angle displacement of the swash plate, the displacement proceeds rapidly at the beginning and gradually progresses closer to the maximum inclination angle.

Since the other components and actions of the compressor are the same as in the conventional case, detailed description thereof will be omitted. However, the variable displacement swash plate compressor according to the present invention adopts a spring having a non-linear displacement characteristic, and in particular, in the case of a compressor set such that the inclination angle of the swash plate is kept to a minimum at an initial stage, the inclination angle of the swash plate is initially increased. Easily increased, the compression is made smoothly, and the time to reach the maximum inclination angle is delayed to prevent sudden increase in torque.

According to the present invention as described above, according to this, since the elastic modulus in each section of the compression coil spring is different, the displacement advances rapidly and gradually up to the maximum inclination angle at the inclination angle displacement of the swash plate. Therefore, the inclination angle of the swash plate is easily increased in the early stage, so that the compression operation can be smoothly performed, and the time and speed of reaching the maximum inclination angle can be delayed to alleviate the impact at the maximum inclination angle support surface of the swash plate, and Sudden fluctuation can be reduced, which can reduce the noise of the compressor and improve the durability of the clutch.

On the other hand, while the above has been shown and described with respect to preferred embodiments of the present invention, the present invention is not limited to the above-described embodiment, the field to which the invention belongs without departing from the spirit of the invention claimed in the claims below Of course, anyone skilled in the art can make various modifications, as well as such modifications are within the scope of the claims.

Claims (3)

A cylinder block having a plurality of axial cylinder bores therein; A front housing mounted to the front of the cylinder block to form a sealed crank chamber therein; A rear housing mounted under the valve plate at the rear of the cylinder block and having a refrigerant suction chamber and a discharge chamber; A drive shaft rotatably supported on the cylinder block and the front housing; A rotor firmly mounted on the drive shaft in the crank chamber; A swash plate connected to the rotor by a hinge mechanism, the swash plate mounted on the driving shaft to change an inclination angle in response to a change in pressure of the crank chamber; A plurality of pistons connected to the outer circumference of the swash plate through the shoe to compress the refrigerant while reciprocating in the cylinder bore according to the rotational rocking motion of the swash plate; A pressure regulating valve for varying a pressure difference between a refrigerant suction pressure in the cylinder bore and a gas pressure in the crank chamber so that the inclination angle of the swash plate varies according to a heat load; And a compression coil spring installed between the rotor and the swash plate to return to the initial position of the swash plate. The compression coil spring is variable displacement swash plate type compressor, characterized in that it has a non-linear displacement characteristics so that the displacement proceeds rapidly at the initial, and up to the maximum inclination angle when the swash plate displacement according to the compressor drive. 2. The variable coil of claim 1, wherein the compression coil spring has a section arranged at a first pitch interval P1 and a section arranged at a second pitch interval P2 greater than the first pitch interval P1. Capacity variable swash plate compressor characterized by consisting of a variable pitch type spring. The variable displacement swash plate compressor of claim 1, wherein the compression coil spring is configured of a conical type spring whose spring diameter gradually increases from one side to the other side.

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