KR101601966B1 - Variable displacement compressor - Google Patents

Abstract

In the variable capacity compressor of the present invention, the suction chamber, the discharge chamber, and the crank chamber are formed. In the variable capacity compressor, a first refrigerant inlet port in which the discharge chamber pressure acts and a refrigerant outlet port connected to the refrigerant inlet port are formed, A valve housing in which an end opposite to the first refrigerant inlet port is opened; A valve body for opening and closing the first refrigerant inlet port; A cover for covering the open end of the valve housing, wherein the crank chamber or the second coolant inlet port in which the suction chamber pressure acts is formed; And a check valve composed of a cover member and a pressing member interposed between the cover and the valve body, wherein the valve body has a first valve body for opening and closing the first refrigerant inlet port and a second valve body for opening and closing the second refrigerant inlet port corresponding to the second refrigerant inlet port And a valve body.

 As a result, the backflow refrigerant discharged to the pressure receiving portion of the first valve body acts at the minimum angle of inclination of the swash plate, so that the first valve body closes the first refrigerant inlet port to prevent backflow of the discharged refrigerant.

Compressor, check valve, discharge, reverse flow

Description

[0001] VARIABLE DISPLACEMENT COMPRESSOR [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a capacity variable type compressor, and more particularly, to a capacity variable type compressor having a check valve for preventing backflow of discharge pressure.

The number of revolutions can not be controlled because the compressor included in the cooling system of the air conditioner for an automobile is directly connected to the engine through the belt.

Therefore, in recent years, a capacity variable compressor capable of changing the discharge amount of the refrigerant in order to obtain the cooling capacity without being restricted by the revolution number of the engine has been widely used.

As the capacity variable type compressor, various types such as swash plate type, rotary type, and scroll type are disclosed.

In the swash plate type compressor, a swash plate provided so as to vary the inclination angle in the crank chamber rotates in accordance with the rotational motion of the rotary shaft, and the piston reciprocates by the rotary motion of the swash plate. In this case, the refrigerant in the suction chamber is sucked into the cylinder by the reciprocating movement of the piston, and is compressed and discharged to the discharge chamber. The inclination angle of the swash plate changes according to the pressure in the crank chamber and the pressure difference in the suction chamber, .

In particular, it is common to adopt an electromagnetic solenoid-type displacement control valve to adjust the pressure of the crank chamber by opening and closing the valve by energization, thereby adjusting the discharge capacity by adjusting the inclination angle of the swash plate.

At this time, the operation of the capacity control valve is controlled by a control unit in which signals such as the detected number of revolutions of the engine, the temperature inside or outside the vehicle, or the evaporator temperature are calculated by a control unit incorporating a CPU or the like, And is sent to an electromagnetic coil.

In addition, a check valve is provided at a discharge port communicated with the discharge chamber to prevent the refrigerant from flowing backward when the compressor is operated at the minimum capacity.

Hereinafter, the structure of the check valve according to the prior art will be described with reference to the drawings.

1 is a longitudinal sectional view showing a check valve of a capacity variable type compressor according to the prior art.

1, the check valve 1 according to the related art is provided with a first refrigerant inlet 2a through which the discharge chamber pressure Pd acts, and a refrigerant outlet port 2a connected to the first refrigerant inlet 2a, A valve housing 2 in which an end opposite to the first refrigerant inlet port 2a is opened and a valve body 3 for opening and closing the first refrigerant inlet port 2a, A cover 4 covering the open end of the valve housing 2 and formed with a second coolant inlet port 4a to which the actual pressures Pc and Ps are applied and a cover 4 between the cover 4 and the valve body 3 And includes an interposed spring (5).

At this time, the discharge chamber pressure Pd acts on the valve body 3, and the crank chamber or the suction chamber pressure Pc, Ps acts on the lower portion.

That is, the valve element 3 closes the first refrigerant inlet port 2a by adding the crank chamber or the suction chamber pressure Pc, Ps to the elastic force of the spring 5.

The check valve 1 constructed as described above is installed at the discharge port of the compressor to prevent the refrigerant from flowing backward in the minimum capacity operation (low pressure discharge).

 However, according to the check valve 1 of the prior art, the differential pressure between the discharge chamber pressure Pd and the crank chamber or the suction chamber pressure Pc, Ps at the time of the minimum capacity operation (compressor OFF) It becomes higher than the set pressure.

That is, due to the differential pressure, the valve element 3 can not close the first refrigerant inlet port 2a, and the refrigerant discharged from the next cooling cycle (condenser) flows back to the compressor.

At this time, the discharged refrigerant flowing backward flows into the swash plate chamber through the check valve 1 and the control valve, and the durability of the swash plate is deteriorated due to the sudden flow noise and the crankcase pressure increase due to the flow of the reverse flow refrigerant.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the related art, and an object of the present invention is to provide a refrigerating device for a refrigerator which is constructed such that a check valve is closed by a pressure of back- And to provide a capacity variable type compressor.

According to another aspect of the present invention, there is provided a capacity variable compressor in which a suction chamber, a discharge chamber, and a crank chamber are formed. The capacity variable compressor includes a first refrigerant inlet through which the discharge chamber pressure acts, A valve housing having a refrigerant outlet port formed therein and having an end opposite to the first refrigerant inlet port opened; A cover for covering the open end of the valve housing, wherein the crank chamber or the second coolant inlet port in which the suction chamber pressure acts is formed; A valve body comprising a first valve body for opening and closing the first refrigerant inlet port and a second valve body movably coupled along the longitudinal direction of the second refrigerant inlet port; And a check valve composed of a cover member and a biasing member interposed between the cover and the first valve body, wherein the first valve body is formed with a water pressure portion to which discharged countercurrent refrigerant acts, And a support portion to be inserted into the support portion is formed.

Preferably, the first valve body is formed with a water pressure portion on which the discharged countercurrent refrigerant acts, and the second valve body is formed with a support portion inserted into the water pressure portion.

Further, it is preferable that the discharge passage connected to the discharge chamber and provided with the check valve is further provided.

Further, it is preferable that a connection channel connecting the crank chamber or the suction chamber and the check valve is provided.

According to the variable capacity compressor of the present invention, since the backflow refrigerant discharged to the pressure receiving portion of the first valve body operates at the minimum inclination angle of the swash plate, the first valve body closes the first refrigerant inlet port to prevent the reverse flow of the discharged refrigerant It is effective.

Thus, the reverse flow of the discharge refrigerant is blocked, and the durability of the swash plate due to the sudden flow noise and the crank chamber pressure increase due to the refrigerant flow is prevented from being lowered.

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

First, the structure of a variable displacement swash plate type compressor having a valve assembly according to the present invention will be schematically described.

FIG. 2 is a longitudinal sectional view showing the structure of a capacity variable type compressor according to the present invention, FIG. 3 is a side sectional view showing a rear housing of the capacity variable type compressor of FIG. 2, FIG.

As shown, the variable displacement swash plate type compressor (C) comprises a cylinder block (10) having a plurality of cylinder bores (12) formed in parallel on its inner circumferential surface in the longitudinal direction, And a rear housing (18) hermetically coupled via a valve plate (20) at the rear of the cylinder block (10).

One end of the drive shaft 44 is rotatably supported near the center of the front housing 16 while the other end of the drive shaft 44 is rotatably supported by the crank chamber 86. The crank chamber 86 is provided on the inside of the front housing 16, Through a crank chamber (86) and a bearing provided on the cylinder block (10).

In the crank chamber 86, a lug plate 54 and a swash plate 50 are provided around the drive shaft 44.

The lug plate 54 is formed with a pair of power transmission support arms 62 formed integrally with one side of the swash plate 50 and each having a guide hole 64 formed at the center thereof. The ball 66 of the swash plate 50 slides in the guide hole 64 of the lug plate 54 as the lug plate 54 rotates, The inclination angle is varied.

The outer circumferential surface of the swash plate 50 is slidably engaged with each piston 14 via a shoe 76.

Accordingly, as the swash plate 50 rotates in an inclined state, the pistons 14 fitted to the outer circumferential surface of the swash plate 50 via the shoe 76 reciprocate in the respective cylinder bores 12 of the cylinder block 10 do.

A valve plate 20 interposed between the rear housing 18 and the cylinder block 10 is provided with a suction chamber 22 and a discharge chamber 24 in the rear housing 18, And a suction valve 32 and a discharge valve 36 are formed at positions corresponding to the discharge port 12, respectively.

The refrigerant in the suction chamber 22 is sucked into the cylinder bore 12 by the reciprocating motion of the piston 14 and is compressed and discharged to the discharge chamber 24. The pressure in the crank chamber 86 and the pressure in the suction chamber The inclination angle of the swash plate 50 changes according to the pressure difference in the discharge chamber 22 or the discharge chamber 24 so that the discharge amount of the refrigerant is regulated by adjusting the pressure of the crank chamber 86 by opening and closing the valve by energization, And a displacement control valve 200 that adjusts the discharge displacement by adjusting the inclination angle of the swash plate 50.

In addition, the rear housing (18) is provided with a discharge passage (101) communicating with the discharge chamber (24). At this time, a check valve 100 is installed in the discharge passage 101 to discharge the refrigerant compressed at a pressure equal to or higher than the set differential pressure to the outside (condenser) and prevent the discharged refrigerant from flowing backward.

Further, it is preferable that a discharge port 25 is formed at the discharge side of the discharge flow path 101.

A connection passage 102 is formed in the rear housing 18 to connect the crank chamber 86 or the suction chamber 22 so that the pressures Pc and Ps act on the check valve 100.

The compressor described above is only one example in which the check valve according to the present invention is installed, and is applicable to all other types of clutch-less capacity variable compressors.

Hereinafter, a check valve 100 according to the present invention will be described with reference to the drawings.

As shown in the figure, the discharge passage 101 is provided in the discharge passage 101 and is connected to the discharge passage 101 by a differential pressure between the pressure Pd of the discharge chamber 24 and the pressures Pc, Ps of the crank chamber 86 or the suction chamber 22, The check valve 100 according to the present invention repeatedly performs the function of sending the refrigerant discharged from the discharge chamber 24 to the next cooling cycle (condenser) and comprises a valve housing 110, A cover 130 which covers the open end of the valve housing 110 and a cover 130 which is interposed between the cover 130 and the valve body 120. [ And a biasing member 140.

The valve housing 110 is provided with a first refrigerant inlet 111 through which the pressure Pd of the discharge chamber 24 acts and a second refrigerant inlet 111 connected to the refrigerant inlet 111 through reciprocating movement of the valve body 120. [ An outlet 112 is formed.

At this time, the first refrigerant inlet 111 is connected to the discharge chamber 24 by the discharge passage 101, and the refrigerant discharge port 112 is connected to the discharge port 25 by the discharge passage 101. That is, the valve housing 110 is installed in the discharge passage 101.

In addition, the valve body 120 opens and closes the first refrigerant inlet 111 by the pressure Pd of the discharge chamber 24. In addition, the valve body 120 acts on the reverse flow refrigerant discharged at the minimum angle of inclination of the compressor, and a detailed description will be given later.

The cover 130 is provided with a second refrigerant inlet 131 through which a crank chamber 86 or a suction chamber pressure Pc, Ps is applied. That is, the second refrigerant inlet port is connected to the connecting oil path (131).

Meanwhile, the urging member 140 is formed of a spring, so that the valve body 120 applies an elastic force in a direction of closing the first refrigerant inlet 111. [

Such a biasing member 140 can adjust the pressure difference at which the valve body 120 is opened or closed according to the magnitude of the elastic modulus.

The valve body 120 includes a first valve body 121 that opens and closes the first refrigerant inlet 111 and a second valve body 121 that is movably coupled along the longitudinal direction of the second refrigerant inlet 131. [ (122), and the first and second valve bodies (121, 122) are separately configured to move.

Meanwhile, the urging member 140 preferably applies an elastic force to the first valve body 121.

The first valve body 121 is formed with a pressure receiving portion 121a to which discharged countercurrent refrigerant acts and the second valve body 122 has a support portion 122a inserted into the pressure receiving portion 121a ).

That is, even when the differential pressure increases as shown in Table 1 at the minimum inclination angle of the compressor due to the action of the reverse-flow refrigerant discharged to the pressure-receiving portion 121a, the check valve 100 of the present invention prevents reverse flow of the discharge refrigerant do.

According to the check valve 100 constructed as described above, the backflow refrigerant discharged to the pressure receiving portion 121a of the first valve body 121 acts upon the minimum inclination angle of the swash plate 50, ) Closes the first refrigerant inlet port 111 to prevent backflow of the discharged refrigerant.

At this time, the elastic force of the biasing member 140 also acts on the first valve body 121.

Thus, the reverse flow of the discharge refrigerant is blocked, and the durability of the swash plate 50 due to the sudden flow noise and the pressure increase of the crank chamber 86 according to the refrigerant flow is prevented from being lowered.

That is, the first valve body 121 reciprocatingly reciprocating with the second valve body 122 and the countercurrent refrigerant discharged to the pressure receiving portion 121a act, The backflow of the discharged refrigerant is completely blocked.

The pressure Pc or Ps of the crank chamber 86 or the suction chamber 22 is transmitted to the second refrigerant inlet port 131 and acts on the lower portion of the second valve body 122, The second valve body 122 having received the pressures Pc and Ps of the suction chamber 86 or the suction chamber 22 is lifted and the support portion 122a supports the lower portion of the pressure receiving portion 121a, As shown in Fig.

That is, the pressure Pc, Ps of the crank chamber 86 or the suction chamber 22 rises at the minimum inclination angle of the swash plate 50, and the pressure Pc, Pc of the crank chamber 86 or the suction chamber 22, Ps act on the check valve 100 through the connection passage 102. At this time, in use of the compressor, the crank chamber pressure Pc and the suction chamber pressure Ps become approximately equal

4A shows a state in which the valve element 120 compresses the urging member 140 by opening the first refrigerant inlet 111 by the pressure Pd of the discharge chamber 24, 4B is a view showing a state in which the countercurrent refrigerant discharged to the pressure receiving portion 121a of the first valve body 121 at the minimum inclination angle of the swash plate 50 is discharged through the cycle (condenser) So that only the first valve body 121 rises and the first refrigerant inlet 111 is closed (BACK FLOW CLOSE) to prevent the reverse flow of the refrigerant. 4 (c) shows a state in which the pressure Pc, Ps of the crank chamber 86 or the suction chamber 22 acts on the second valve body 122, so that the support portion 122a of the second valve body 122, The pressure receiving portion 121a of the body 121 is supported to shut off the first refrigerant inlet 111 to prevent reverse flow of the refrigerant.

Although the preferred embodiments of the present invention have been described in detail, the technical scope of the present invention is not limited to the above-described embodiments, but should be construed according to the claims. It will be understood by those skilled in the art that many modifications and variations are possible without departing from the scope of the present invention.

For example, it is not necessary to limit the installation position of the check valve 100 as described above, and if the check valve 100 can be operated if the pressure Pd of the discharge chamber 24 and the pressure Pc of the crank chamber 86 can act, It should be noted that the installation position of the battery pack may be variously changed.

1 is a longitudinal view showing a check valve of a capacity variable compressor according to the prior art.

2 is a longitudinal sectional view showing a structure of a capacity modulation compressor according to the present invention.

3 is a side cross-sectional view showing the rear housing of the capacity variable type compressor of Fig.

4 is a longitudinal sectional view showing the structure of a check valve according to the present invention.

Description of the Related Art

100 - check valve 110 - valve housing

120 - valve body 130 -

140 - Cover

Claims (4)

1. A capacity modulation compressor in which a suction chamber, a discharge chamber, and a crank chamber are formed, A valve housing having a first refrigerant inlet port through which the discharge chamber pressure acts and a refrigerant outlet port connected with the refrigerant inlet port, the valve housing having an end opposite to the first refrigerant inlet port opened; A cover for covering the open end of the valve housing, wherein the crank chamber or the second coolant inlet port in which the suction chamber pressure acts is formed; A valve body comprising a first valve body for opening and closing the first refrigerant inlet port and a second valve body movably coupled along the longitudinal direction of the second refrigerant inlet port; And And a check valve composed of a cover member and a biasing member interposed between the cover and the first valve body, Wherein the first valve body is formed with a water pressure portion to which the discharged countercurrent refrigerant acts, and the second valve body is formed with a support portion inserted into the water pressure portion. delete The method according to claim 1, And a discharge passage connected to the discharge chamber and provided with the check valve. The method of claim 3, And a connecting passage for connecting the crank chamber or the suction chamber to the check valve.

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