KR100329158B1 - Apparatus for relieving start shock in compressors - Google Patents

Abstract

The present invention has a header on the upper surface of the rear housing so as to be connected to an external refrigerant circuit through respective refrigerant inlets and refrigerant outlets communicating with the suction chamber and the discharge chamber formed inside the compressor housing. The initial starting torque is alleviated by controlling the amount of refrigerant drawn into the refrigerant suction hole and the auxiliary suction hole by the torque output of the compressed refrigerant during the initial startup of the compressor via the piston whose position is displaced.

Description

Apparatus for relieving start shock in compressors}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston compressor for vehicle air conditioning, and more particularly to a starting shock mitigation device applied to the compressor.

In general, in a fixed displacement double head piston compressor, a double head piston is accommodated in a cylinder bore formed in a cylinder block.

The suction chamber and the discharge chamber are partitioned in the front housing and the rear housing, respectively. The refrigerant gas in the suction chamber is sucked into the cylinder bore by the reciprocating operation of the piston and compressed, and is discharged into the compression chamber.

In the double-head piston piston compressor, valve plates are formed at discharge ports corresponding to cylinder bores, respectively. A fixed discharge valve is provided corresponding to the discharge port, and the discharge valve is closed when the refrigerant gas is inhaled, and is opened when the refrigerant gas is discharged.

These compressors are connected to an external drive source such as a vehicle engine as the electric clutch installed in front of the compressor is energized so as to compress the suction refrigerant while the piston in the compressor reciprocates. For this reason, the compression load of a compressor rises rapidly.

In particular, in the vehicle-mounted form, this sudden change in compression load is transmitted to an external drive source such as a vehicle engine as a change in load torque, which may cause a change in the rotational speed of the vehicle engine or the like, or may cause a high temperature of the compressor. This change in rotational speed is called an on / off shock, resulting in deterioration of haptic peeling.

In addition, at the start of the compressor, a compressive force is applied to the liquid refrigerant sucked into the cylinder bore. When the compressor is in the liquid compression state, a large compression load is applied to the piston, which causes shock vibration or noise.

In view of this point, various compressors having a starting shock mitigating device have been disclosed, but there is a shortage of mitigating starting shock.

The present invention is to solve the above problems, the compressor compressor refrigerant is allowed to vary the suction inlet of the manifold until the normal pressure is achieved and the suction refrigerant is normally introduced through the suction port when the temperature of the compressed refrigerant rises in the continuous operation of the compressor The purpose is to reduce startup shock during initial startup.

In order to achieve this object, the present invention provides a front and rear housing fixed to each end of the pair of cylinder blocks via a valve plate, a plurality of cylinder bores formed in the cylinder block and each receiving a piston, and the housing And a suction chamber and a discharge chamber, each of which is partitioned therein, and the refrigerant gas is sucked from the suction chamber into the compression chamber in the cylinder bore by the reciprocating motion of the piston and compressed, and then discharged into the discharge chamber through the discharge port formed in the valve plate. A piston-type compressor having a configuration, comprising: a header on an upper surface of a rear housing to be connected to an external refrigerant circuit through respective refrigerant inlets and refrigerant outlets communicating the suction chamber and the discharge chamber formed in the housing; Are partitioned by the dividing wall into suction and discharge ports, respectively; A portion of the high pressure refrigerant discharged through the partition wall and discharged to the discharge port has a refrigerant bypass hole bypassed to the suction port; The suction port has a small diameter auxiliary suction hole connected in parallel with the refrigerant suction hole to suck a minimum amount of refrigerant;

In order to change the suction area of the refrigerant suction hole and the auxiliary suction hole communicated with the suction port in response to a change in the discharge pressure of the discharge refrigerant at the initial startup of the compressor, an imaginary ship connecting the refrigerant suction hole and the auxiliary suction hole. It has a piston for varying the suction area of the refrigerant suction hole and the auxiliary suction hole through the position displacement; The piston includes a suction control hole penetrating in a thickness direction and having a cross-sectional area at least larger than the refrigerant suction area of the refrigerant suction hole; An elastic member elastically supporting the displacement position of the piston in response to the discharge pressure of the discharge refrigerant; And a stopper for limiting the stroke distance of the piston, wherein the initial starting torque is mitigated by adjusting the amount of refrigerant suctioned into the refrigerant suction hole and the auxiliary suction hole by the torque output of the compressed refrigerant during initial startup of the compressor. It is done.

1 is a longitudinal cross-sectional view of a double head piston compressor of the present invention;

2 is a perspective view of a header part showing the main part of the present invention;

3 is a cross-sectional view for explaining an operating state of the present invention.

* Description of the symbols for the main parts of the drawings *

50, 51: Cylinder block 52: Cylinder bore

58: front housing 59: rear housing

60, 61 valve plate 68 discharge chamber

70, 71: discharge valve 100: header

101: discharge port 102: suction port

103: dividing wall 104: bypass hole

105: refrigerant suction hole 106: auxiliary suction hole

110: piston 111: suction regulator hole

112: coil spring 113,114: stopper

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. 1 is a longitudinal cross-sectional view of a compressor according to the present invention, Figure 2 is a perspective view of the main portion showing the header portion, Figure 3 is a plan view of Figure 2 for explaining the operating state.

The compressor of the reciprocating piston type according to the present invention has a front cylinder block 50 and a rear cylinder block 51, which cylinder blocks 50 and 51 are coupled to each other axially to form a cylinder block assembly. The cylinder block assembly is housed in the front housing 58 and the rear housing 59, and the front and rear valve plates 60, 61 and the housing 58 interposed between the cylinder block assembly and the front and rear housings 58, 59. 59) both ends are closed.

Through holes are formed in the front and rear housings 58 and 59 and the front and rear cylinder blocks 50 and 51, and are firmly coupled by the through bolts 64. The coupled cylinder blocks 50 and 51 have center bores 57 and 57a at the center of the shaft, and the drive shaft 65 is coupled to the center bore. Thrust bearings 57b and 57c are coupled around the drive shaft to facilitate rotation of the drive shaft.

The cylinder block assembly is provided with a plurality of cylinder bores 52, for example five front cylinder bores and five rear cylinder bores provided coaxially. This cylinder bore is disposed radially on the same circumference around the drive shaft 65. Five opposite head pistons 53 are inserted into each of the opposed cylinder bores 52 and are engaged with the swash plate 54 coupled with the drive shaft 65 by a hemispherical shoe 56 by rotation of the swash plate 54. It reciprocates in the cylinder bore 52.

The crank chamber 55 is provided at the center of the coupled cylinder blocks 50 and 51, and the swash plate 54 is accommodated in the crank chamber 55. The swash plate 54 is mounted on the drive shaft 65 to rotate in accordance with the rotation of the drive shaft 65, thereby causing the two head piston 53 in the cylinder bore 52 to reciprocate. As each piston 53 in the cylinder bore 52 reciprocates, suction and discharge of the refrigerant gas are performed.

A front discharge chamber 68 and a rear discharge chamber 69 are formed in each of the front housing 58 and the rear housing 59, and the front suction chamber 74 and the rear suction chamber 75 are respectively formed outside the front housing 58 and the rear housing 59. . The front valve plate 60 and the rear valve plate 61 have a front inlet 78 and a rear inlet 79, respectively, so that fluid communication between the suction chambers 74 and 75 and the individual cylinder bores 52 is achieved. Is done.

The front valve plate 60 and the rear valve plate 61 have a front discharge port 72 and a rear discharge port 73, respectively, so that fluid communication between the discharge chambers 68 and 69 and the respective cylinder bores 52 is carried out. Is done. In other words, the suction ports 78 and 79 are compressed by the compression stroke of the double head piston 53 by allowing the low pressure refrigerant gas to flow into the respective cylinder bores 52. The discharge ports 72 and 73 allow the high pressure compressed refrigerant gas to be discharged from the cylinder bore 52 to the discharge chambers 68 and 69 by the compression stroke of the double head piston 53.

The inlets 78 and 79 respectively have front and rear suction valves 76 having reed valves 76a and 77a in contact with the inner surfaces of the front and rear valve plates 60 and 61, i.e., the surfaces in contact with the cylinder block assembly. 77). Similarly, the discharge openings 72 and 73 have front and rear reed valves 76a and 77a in contact with the outer surfaces of the front and rear valve plates 60 and 61, that is, the surfaces that contact the front and rear housings 58 and 59. It is closed by the rear discharge valves 70 and 71.

The reed valves 76a, 77a, 70a, 71a of the suction and discharge valves 76, 77, 70, and 71 are respectively corresponding to the inlets 78, 79 and the discharge ports 72 by the reciprocating motion of the double head piston 53. 73), thereby opening the respective inlets and outlets.

Between the outer circumferential surface of the cylinder blocks 50 and 51 and the inner circumferential surfaces of the front and rear housings 58 and 59, predetermined gaps 67 and 67a are formed, and a cutout portion is formed on the outer circumferential wall of the cylinder blocks 50 and 51. Not shown) is provided.

In addition, since some of the through grooves 62 and 62a to which the through bolt 64 is fastened are formed larger than the diameter of the through bolt, the suction passage is formed in the axial direction for the movement of the refrigerant gas in the state where the through bolt is fastened. It is formed in the blocks (50, 51). Similar holes are formed in the valve plates 60 and 61 and the suction valves 76 and 77 corresponding to the suction passages formed in the cylinder blocks 50 and 51.

Therefore, the refrigerant introduced from the refrigerant inlet 96 is introduced into the crank chamber 55 through the cut portions of the cylinder blocks 50 and 51. The refrigerant introduced into the crank chamber 55 is sucked into the front suction chamber 74 and the rear suction chamber 75 of each of the front housing 58 and the rear housing 59 through the suction passage. Then, by the compression stroke of the piston 53, the reed valves 76a and 77a of the front and rear suction valves 76 and 77 are opened to suck the refrigerant gas into the respective cylinder bores.

In the central portion of the bottom surface of the front and rear housings 58 and 59, polymorphic front inner walls 82 and 83 having a predetermined thickness and projecting upwardly from the bottom surface are formed. The front inner walls 82 and 83 extend by a predetermined length and come into contact with the front and rear valve plates 60 and 61 on their upper surfaces.

At one end of the front inner wall 82, a transfer discharge port 91 extends from the front inner wall 82. The front discharge chamber 68 and the front suction chamber 74 are provided by the front inner wall 82 and the inner circumferential wall of the front housing 58.

An extension 93 is formed at one end of the rear inner wall 83, and the rear discharge chamber 69 and the rear suction chamber 75 are provided by the inner peripheral wall of the rear inner wall 83 and the rear housing 59. .

In the discharge chamber 69 of the rear housing 59, a discharge tube 89 is formed in communication with the discharge chamber 92 for discharging the refrigerant gas discharged into the discharge chamber 69 to the outside of the compressor. One end of the 89 is extended by a predetermined length in the discharge chamber 69 and the other end is connected to the outflow chamber 92.

Figure 2 is a perspective view showing the header of the compressor as a means for mitigating the compressor starting shock according to the present invention.

The header 100 has a rear housing connected to an external refrigerant circuit through respective refrigerant outlets 97 and refrigerant inlets 96 communicating the rear discharge chamber 69 and the rear suction chamber 75 formed inside the housing. 59) is formed on the upper surface.

In the header 100, a discharge port 101 and a suction port 102 are respectively partitioned by a partition wall 103, and a refrigerant bypass hole 104 penetrates the partition wall 103 so that the discharge port is discharged. Some of the high pressure refrigerant discharged to 101 is bypassed to the suction port 102. The bottom surface of the suction port 102 is connected in parallel with the refrigerant suction hole 105, the secondary suction hole 106 of a small diameter for the minimum refrigerant is sucked is formed.

Furthermore, according to an embodiment of the present invention, in order to vary the suction area of the refrigerant suction hole 105 and the auxiliary suction hole 106 in communication with the suction port 102 in response to a change in the discharge pressure of the discharge refrigerant at the initial startup of the compressor. The variable means is elastically installed in the suction port 102.

The variable means includes a piston for varying the suction area of the refrigerant suction hole 105 and the auxiliary suction hole 106 through a positional displacement on an imaginary line connecting the refrigerant suction hole 105 and the auxiliary suction hole 106 ( 110, wherein the piston 110 includes a suction control hole 111 penetrating in the thickness direction and having a cross-sectional area at least larger than the refrigerant suction area of the refrigerant suction hole 105.

Here, the suction control hole 111 has a diameter at least larger than the distance between the center of the refrigerant suction hole 105 and the center of the auxiliary suction hole 106, the piston 110 when the refrigerant discharge pressure is normal. It is important to prevent the refrigerant suction hole 105 from being blocked.

The piston 110 is elastically supported by the coil spring 112 so that the displacement position of the piston 110 is adjusted in response to the discharge pressure of the discharge refrigerant, and the piston 110 on the inner wall of the suction port 102. A pair of stoppers 113 and 114 are formed before and after the direction of movement of the piston to limit the stroke distance of the piston 110. Furthermore, a suction port 102 is provided on the outer circumference of the first half of the piston 110. FIG. O-ring 115 is installed to prevent the airtight while slidingly reciprocating).

In the compressor configured as described above, the refrigerant gas is introduced into the crank chamber 55 through the refrigerant inlet 96 and then sucked into the front and rear suction chambers 74 and 75 through the suction passages. The refrigerant gas stored in the suction chambers 74 and 75 opens and closes the reed valves 76a and 77a of the front and rear suction valves 76 and 77 according to the reciprocating motion of the piston 53 and accordingly the front and rear suction ports 78. 79 is sucked into the individual cylinder bores 52.

The refrigerant gas compressed by the compression stroke of the piston 53 is opened by the respective cylinders through the front and rear discharge ports 72 and 73 by opening and closing the reed valves 70a and 71a of the front and rear discharge valves 70 and 71. Discharges from the bore 52 into the front and rear discharge chambers 68 and 69. The refrigerant gas discharged into the discharge chamber 69 of the rear housing 59 is discharged to the outside of the compressor through the discharge chamber 89 and the discharge chamber 92 and the discharge port 98.

At this time, since the gas refrigerant compressed by the piston 53 at the initial startup of the compressor is a low temperature unstable state, a large compression load is applied to the piston to generate shock vibration or noise.

Therefore, the present invention prevents starting shock by adjusting the suction amount of the refrigerant sucked into the suction chamber 75 until the compressed refrigerant is stabilized at the initial startup of the compressor.

That is, the pressure of the discharge refrigerant compressed by the piston 53 at the initial startup is low, and the refrigerant discharged in such a state is externally via the refrigerant outlet 97 through the discharge port 101 of the header 100. In this case, a portion of the discharged refrigerant flows into the suction port 102 through the bypass hole 104 formed in the dividing wall 103 to apply pressure to the piston 110.

When the pressure of the discharge refrigerant acts on the piston 110, the piston 110 is retracted in proportion to the pressure of the refrigerant while being resisted by the elastic modulus of the coil spring 112, and at the same time the refrigerant sucked from the external circuit is shown in Figure 3a. Since the refrigerant suction hole 105 is blocked by the piston 110 as described above, only the minimum refrigerant is sucked through the auxiliary suction hole 106 to adjust the amount of refrigerant sucked at the initial startup of the compressor.

The auxiliary suction hole 106 needs to be kept open at all times during the initial startup, and therefore, it is possible to limit the forward distance of the piston 110 by the stopper 113 formed on the inner wall of the suction port 102.

Since the pressure of the discharged refrigerant rises while the refrigerant is gradually stabilized, the piston 110 gradually retreats backward as shown in FIGS. 3B and 3C, and at the same time the suction control hole 111 formed in the piston 110 and The refrigerant suction hole 105 is in communication.

As the discharge pressure of the discharge refrigerant increases, as the position of the piston 110 is displaced, the suction area of the refrigerant suction hole 105 gradually increases in proportion to this, and the suction refrigerant flows normally into the compressor. Starting torque can be reduced.

As described above, the present invention can reduce the starting torque caused by the instability of the refrigerant during initial compressor startup by adjusting the amount of refrigerant sucked in proportion to the discharge pressure.

Claims (4)

A front and rear housing fixed to each end of the pair of cylinder blocks via a valve plate, a plurality of cylinder bores formed in the cylinder block to receive pistons, and a suction chamber and a discharge chamber respectively defined in the housing. In the piston-type compressor having a configuration in which the refrigerant gas is sucked into the compression chamber in the cylinder bore in the suction chamber by the reciprocating motion of the piston, and then discharged into the discharge chamber through the discharge port formed in the valve plate, A) having a header on the upper surface of the rear housing to be connected to an external refrigerant circuit through respective refrigerant suction holes and refrigerant discharge holes communicating the suction chamber and the discharge chamber formed inside the housing, a) the header is partitioned by a dividing wall into suction and discharge ports respectively; b) a portion of the high pressure refrigerant discharged through the dividing wall to the discharge port has a refrigerant bypass hole bypassed to the suction port; c) the suction port has a small diameter auxiliary suction hole connected in parallel with the refrigerant suction hole to suck the minimum amount of refrigerant; B) to change the suction area of the refrigerant suction hole and the auxiliary suction hole in communication with the suction port in response to a change in the discharge pressure of the discharge refrigerant at the initial startup of the compressor, a) having a piston for varying suction areas of the refrigerant suction hole and the auxiliary suction hole through a positional displacement on an imaginary line connecting the refrigerant suction hole and the auxiliary suction hole; The piston includes a suction control hole penetrating in the thickness direction; b) an elastic member elastically supporting the displacement position of the piston in response to the discharge pressure of the discharge refrigerant; And c) a stopper for limiting the stroke distance of the piston; An initial starting torque mitigating device, characterized in that for reducing the initial starting torque by adjusting the amount of refrigerant sucked into the refrigerant suction hole and the auxiliary suction hole by the output of the compressed refrigerant during the initial startup of the compressor. The apparatus of claim 1, wherein an O-ring is interposed between the outer periphery of the piston to be in close contact with the inner wall of the suction port. The compressor starting shock relief device according to claim 1, wherein the suction control hole formed in the piston is larger than the suction cross-sectional area of the refrigerant suction hole. The apparatus of claim 3, wherein the suction control hole has a diameter that is at least larger than a distance between a center of the refrigerant suction hole and a center of the auxiliary suction hole.