KR101866731B1 - Variable displacement swash plate type compressor - Google Patents

Abstract

The present invention relates to a variable displacement swash plate type compressor capable of improving suction pulsation and initial operation delay, in which a spool chamber communicating with a suction chamber is formed in a rear portion of a center bore of a cylinder block, and one side wall of the spool chamber communicates with a crank chamber And a second communication path communicating with the pressure control valve is formed on the other side of the side wall of the spool chamber.

Description

[0001] DESCRIPTION [0002] VARIABLE DISPLACEMENT SWASH PLATE TYPE COMPRESSOR [0003]

The present invention relates to a swash plate compressor, and more particularly, to a variable displacement swash plate compressor capable of improving suction pulsation and initial operation delay.

Generally, compressors for compressing refrigerant in a vehicle cooling system have been developed in various forms. Such a compressor includes a reciprocating type in which compression is performed while reciprocating the refrigerant, There is a rotary that performs.

Here, the reciprocating type includes a crank type in which the driving force of the drive source is transmitted to a plurality of pistons by using a crank, a swash plate type in which the swash plate is transmitted to a swash plate provided with a swash plate, a wobble plate type in which a wobble plate is used, Vane rotary using vanes, scroll type using revolving scroll and fixed scroll.

On the other hand, as the swash plate type compressor, there are a fixed displacement type in which the installation angle of the swash plate is fixed and a variable displacement type in which the discharge displacement can be changed by changing the inclination angle of the swash plate.

FIG. 1 shows the construction of a general variable capacity swash plate type compressor. Hereinafter, a schematic configuration of the variable displacement swash plate type compressor will be described with reference to FIG.

A variable capacity swash plate type compressor 10 is provided with a cylinder block 20 forming a part of an outer appearance and a skeleton of the compressor 10. At this time, a center bore 21 is formed through the center of the cylinder block 20, and a rotation shaft 60 is rotatably installed in the center bore 21. [

A plurality of cylinder bores 22 are formed through the cylinder block 20 so as to radially surround the center bore 21. A piston 70 is installed in the cylinder bore 22 so as to reciprocate linearly. At this time, the piston 70 is formed in a cylindrical shape, and the cylinder bore 22 is a cylindrical space corresponding to the cylinder bore 22. The refrigerant in the cylinder bore 22 is compressed by the reciprocating motion of the piston 70.

The front housing 30 is coupled to the front of the cylinder block 20. The front housing 30 faces the cylinder block 20 to form a crank chamber 31 together with the cylinder block 20. [

A pulley 32 connected to an external power source such as an engine is rotatably mounted on the front of the front housing 30 so that the rotary shaft 60 rotates in conjunction with the rotation of the pulley 32.

A rear housing (40) is coupled to the rear of the cylinder block (20). A discharge chamber 41 is formed in the rear housing 40 along a position adjacent to the outer circumferential edge of the rear housing 40 so as to selectively communicate with the cylinder bore 22. The discharge chamber 41 is formed in a radial direction of the discharge chamber 41 A suction chamber 42 is formed at the center of the rear housing 40.

A valve plate 50 is interposed between the cylinder block 20 and the rear housing 40 and the discharge chamber 41 is connected to the cylinder bore 22 through the discharge port 51 formed in the valve plate 50. [ And the suction chamber 42 communicates with the cylinder bore 22 through the suction port 52 of the valve plate 50. [

The swash plate 61 is provided on the rotary shaft 60. The swash plate 61 is connected to the respective pistons 70 by a shoe 62 provided along the rim of the swash plate 61. By the rotation of the swash plate 61, (70) reciprocates linearly in the cylinder bore (22).

The angle of the swash plate 61 relative to the rotary shaft 60 is variable so that the refrigerant discharge amount of the compressor 10 can be adjusted. To this end, the discharge chamber 41 and the crank chamber 31 are communicated with each other Is controlled by a pressure control valve (not shown).

However, there is a problem in that suction pulsation occurs due to irregular pressure during the suction stroke of the general compressor 10, and noise is generated thereby. In order to solve this problem, conventionally, the suction chamber volume is increased, (See Patent Document 1), or a method of adding a pressure damping device such as a suction check valve (see Patent Document 2) to improve the suction pulsation.

However, the above-described methods cause a limitation of the increase of the suction volume due to the miniaturization and weight reduction of the compressor and a cost increase due to the addition of the muffler, and even when the pressure damping device is applied, There is a problem that there is a limit.

Patent Document 1: Korean Patent Laid-open No. 10-2011-0137566 (2011.12.23) Patent Document 2: Korean Patent Laid-open No. 10-2011-0058017 (June 1, 2011)

The present invention has been devised in order to solve the problems as described above, and one embodiment of the present invention can obtain the effect of improving the pulsation by preventing excessive change in the suction chamber pressure at the maximum operation of the compressor, And it is an object of the present invention to provide a variable displacement swash plate type compressor capable of improving the initial operation delay by sufficiently ensuring the communication path of the suction chamber.

According to a preferred embodiment of the present invention, a cylinder block having a center bore formed at a center thereof and having a plurality of cylinder bores spaced apart from each other in the circumferential direction at a radially outer side of the center bore; A front housing coupled to the front of the cylinder block and having a crank chamber formed therein; A rear housing coupled to the rear of the cylinder block and having a suction chamber and a discharge chamber formed therein; A rotating shaft rotatably installed through the center of the front housing and the cylinder block; A swash plate coupled to the rotary shaft through a central portion thereof so as to rotate integrally with the rotary shaft, and slantedly installed in the crank chamber; A plurality of pistons coupled to one side of the swash plate and reciprocating linearly by rotation of the swash plate; A first communication passage formed at one side of the cylinder block to communicate with the crank chamber; A spool chamber formed at the rear of the center bore to communicate with the suction chamber and communicating with the first communication passage; And a spool valve installed in the spool chamber and elastically supported at a rear end of the rotary shaft for opening and closing the first communication passage.

At this time, a second communication path communicating the discharge chamber and the spool chamber is formed on the other side of the cylinder block.

A valve plate is interposed between the cylinder block and the rear housing, and one side of the first communication path communicates with the suction chamber by an orifice hole formed in the valve plate.

At this time, it is preferable that the diameter of the first communication path is 2.5 mm to 20 mm.

At this time, the spool valve includes an elastic member whose one end is supported by the valve plate, a head portion supported by the other end of the elastic member and facing the rear end of the rotation shaft, And an opening / closing part that is formed to extend in close contact with the first communication path and opens / closes the first communication path.

According to the variable capacity swash plate type compressor according to the preferred embodiment of the present invention, when the pressure in the suction chamber is excessively lowered during the suction stroke, the refrigerant is sucked from the outside through the suction port, The refrigerant is sucked into the suction chamber through the spool chamber from the crank chamber, thereby improving the initial operation delay and the suction pulsation.

1 is a sectional view of a conventional variable displacement swash plate type compressor.
2 is a sectional view of a variable displacement swash plate type compressor according to an embodiment of the present invention;
3 is an operational view of the spool valve at the time of initial operation or maximum operation of the compressor.
4 is an operational view of the spool valve in variable operation of the compressor.

Hereinafter, preferred embodiments of a variable displacement swash plate type compressor according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

In addition, the following embodiments are not intended to limit the scope of the present invention, but merely as exemplifications of the constituent elements set forth in the claims of the present invention, and are included in technical ideas throughout the specification of the present invention, Embodiments that include components replaceable as equivalents in the elements may be included within the scope of the present invention.

Example

2 is a cross-sectional view of a variable displacement swash plate type compressor according to an embodiment of the present invention.

2, a variable capacity swash plate type compressor 100 according to an exemplary embodiment of the present invention includes a housing 200, a rotary shaft 700, a swash plate 800, And includes a plurality of pistons (900).

2, the housing 200 includes the cylinder block 300, the front housing 400, and the rear housing 500, as shown in FIG.

At this time, the cylinder block 300 is a tubular body disposed at an intermediate portion in the longitudinal direction of the housing 200. The cylinder block 300 includes a center bore 310 capable of receiving the rotation shaft 700 therein, A cylinder bore 320 capable of accommodating a plurality of pistons 900 is formed at a radially outer side of the center bore 310. A suction chamber 510 of the rear housing 500, And the spool chamber 330 communicating therewith is formed.

The front housing 400 and the rear housing 500 are connected to each other so as to close the open ends at the front and rear sides of the cylinder block 300. The front housing 400 has a rear end opened toward the cylinder block 300, So as to accommodate the inclination adjusting mechanism 411 for adjusting the inclination angle of the swash plate 800 while securing the crank chamber 410 which is the rotating space of the swash plate 800. [

The rear housing 500 has a front end opened toward the cylinder block 300 and includes a suction chamber 510 for supplying the refrigerant to the cylinder bore 320 of the cylinder block 300 during an intake stroke, A discharge chamber 520 through which the compressed refrigerant in the cylinder bore 320 is discharged during the compression stroke is formed.

At this time, the valve plate 600 interposed between the cylinder block 300 and the rear housing 500 is formed with an inlet port 610, an inlet port 620 and a discharge port 630. The inlet port 610 is connected to the spool chamber 600 And the discharge port 630 communicates the cylinder bore 320 and the discharge chamber 520 with each other so that the cylinder bore 320 communicates with the suction chamber 510. The discharge port 630 communicates the cylinder bore 320 with the discharge chamber 510, .

The rotary shaft 700 is a means for transmitting the rotational driving force of an external driving source (not shown) to the interior of the compressor 100. The rotary shaft 700, which is exposed to the outside of the front housing 400, And an external rotational driving force is transmitted to the rotating shaft 700 through the rotating pulley 710 so that the rotating shaft 700 is rotated.

The front end of the rotary shaft 700 is rotatably installed on one side of the housing, that is, the center of the front housing 400. The rear end of the rotary shaft 700 passes through the center bore 310 formed in the center of the cylinder block 300 And is rotatably installed.

The rotating shaft 700 is rotatably supported by a radial bearing 720 disposed at both ends of the rotating shaft 700. The rear end of the rotating shaft 700 extends to the spool chamber 330, A spring washer 740 is interposed between the thrust bearing 730 and the circular support plate 750 at the rear end of the spool chamber 700 and the support plate 750 is fixed to the side wall of the spool chamber 330.

A first communication path 331 communicating with the crank chamber 410 is formed at one side of the spool chamber 330 at the rear of the support plate 750. The first communication path 331 is formed inside the cylinder block 300, A second communication passage 332 communicating with the discharge chamber 520 through a pressure control valve (not shown) is formed in the other side of the cylinder block 300.

One side of the first communication path 331 communicates with the suction chamber 510 through an orifice hole 640 formed in the valve plate 600 and a spool valve 340 is installed in the spool chamber 330 And is elastically supported at the rear of the support plate 750.

In the conventional case, the diameter of the orifice communicating between the crank chamber 410 and the suction chamber 510 is generally 1.6 mm to 2.4 mm, and the first communication passage 331 according to the embodiment of the present invention is larger Diameter, and the first communication path 331 may be formed to have a diameter of 2.5 mm to 20 mm in consideration of the manufacturing cost and the pulsation improving effect.

The spool valve 340 opens the first communication path 331 during the initial operation or the maximum operation of the compressor 100 so that the refrigerant in the crank chamber 410 flows through the first communication path 331 and the spool chamber 330, The inlet port 610 is closed to allow the refrigerant to be sucked into the suction chamber 510 through the inlet port 610 and the refrigerant discharge amount of the compressor 100 is adjusted by the inclination angle of the swash plate 800, And a variable operation is performed. This will be described later with reference to FIGS. 3 and 4. FIG.

The swash plate 800 is a means for converting the rotational driving force of the rotating shaft 700 into a reciprocating linear motion of the piston 900. The swash plate 800 is installed in an inclined state on the rotating shaft 700 through a central portion, And rotates integrally.

At this time, a plurality of shoes 810 are provided along the circumferential direction at the rim of the swash plate 800, and the plurality of pistons 900 are slidably supported by the shoe 810.

For example, when the slope of the swash plate 800 relative to the rotating shaft 700 is 90 °, the swash plate 800 is rotated in the direction of the arrow A, The reciprocating movement of the piston 900 disappears, so that the rotating shaft 700 idles.

Alternatively, when the swash plate 800 is inclined with respect to the rotary shaft 700, the piston 900 reciprocates within the cylinder bore 320 and compresses the refrigerant. The adjustment of the inclination angle of the swash plate 800 is performed by a pressure control valve (not shown) installed at one side of the rear housing 500 to adjust the opening degree of a passage (not shown) communicating with the discharge chamber 520 and the crank chamber 410 Time).

The plurality of pistons 900 are means for compressing the refrigerant while reciprocating in the cylinder bore 320 by means of the swash plate 800. As shown in FIG. 2, the shoe 810 And is linearly reciprocated along the inner circumferential surface of the cylinder bore 320 of the cylinder block 300 by the rotation of the swash plate 800 to thereby reciprocate the inner circumferential surface of the cylinder bore 320 through the inlet port 620, Thereby compressing the refrigerant.

At this time, the refrigerant compressed by the cylinder bore 320 by the piston 900 is discharged to the discharge chamber 520 of the rear housing 500 and then supplied to the external cooling system through the discharge port (not shown).

FIG. 3 is an operational state view of the spool valve at the time of initial operation or maximum operation of the compressor, FIG. 4 is an operational state view of the spool valve at the time of variable operation of the compressor, and arrows indicated by two-dotted lines indicate the flow direction of the refrigerant.

3 and 4, the spool valve 340 according to the embodiment of the present invention includes an elastic member 341 such as a coil spring whose one end is supported at the rim of the inlet port 610 of the valve plate 600 And a valve body 342 elastically supported by the elastic member 341 in the direction of the support plate 750.

The valve body 342 includes a head portion 343 opposed to the rear end of the rotary shaft 700 and an opening and closing portion formed to extend rearward along the rim of the head portion 343 and in close contact with the side wall of the spool chamber 330 344).

An insertion groove 343a through which one end of the elastic member 341 is inserted is formed along the rear edge of the head 343 and a protrusion 700a at the rear end of the rotary shaft 700 is formed at the center of the front end of the head 343, The receiving groove 343b is recessed and formed.

One end of the elastic member 341 is supported by the valve plate 600 and the other end is supported by the insertion groove 343a of the head portion 343 to elastically support the valve body 342 in the direction of the support plate 750 The valve body 342 opens and closes the first communication path 331 communicating with one side of the side wall of the spool chamber 330 while the opening and closing part 344 slides in the forward and backward directions along the side wall of the spool chamber 330 .

3, the head portion 343 of the valve body 342 is pressed by the resilient force of the elastic member 341 during the initial operation or the maximum operation of the compressor 100, The inlet port 610 is opened from the valve body 342 and the opening and closing part 344 of the valve body 342 is separated from the side wall part of the spool chamber 330 where the first communication path 331 is formed The first communication path 331 is placed in an open state in which the crank chamber 410 communicates with the spool chamber 330 and the suction chamber 510.

The refrigerant in the crank chamber 410 sequentially flows through the first communication path 331 and the spool chamber 330 and is sucked into the suction chamber 510 through the inlet port 610. At this time, do. It goes without saying that the refrigerant is drawn into the suction chamber 510 from the outside of the compressor 100 through the suction port.

Therefore, in the suction stroke of the compressor 100 at the maximum operation, the refrigerant is sucked in the crank chamber 410 together with the suction of the refrigerant through the suction port, thereby preventing excessive pressure change in the suction chamber 510, Can be obtained. Further, the communication passage between the crank chamber 410 and the suction chamber 510 is sufficiently secured during the initial operation, thereby improving the initial operation delay.

4, when the refrigerant discharge amount of the compressor 100 is adjusted, the high-pressure refrigerant in the discharge chamber 520 flows through the second communication path 332 communicated with the pressure control valve, The high pressure refrigerant passes through the support plate 750 and pushes the head portion 343 of the valve body 342 backward to move the opening and closing portion 344 backward and the inlet port 610 ).

At this time, a predetermined gap is formed between the first communication path 331 and the opening / closing part 344 so that the high-pressure refrigerant flowing into the spool chamber 330 flows out to the first communication path 331 through the gap, Some of the high-pressure refrigerant moves to the crank chamber 410 along the first communication path 331 and the rest is sucked into the suction chamber 510 through the orifice hole 640. As a result, the refrigerant in the crank chamber 410 is prevented from flowing into the spool chamber 330 during the suction stroke, and normal variable operation is performed.

100: compressor 200: housing
300: cylinder block 310: center bore
320: Cylinder bore 330: Spool seal
331: first communication path 332: second communication path
340: spool valve 341: elastic member
342: valve body 400: front housing
500: rear housing 510: suction chamber
520: Discharge chamber 600: Valve plate
610: inlet 620: inlet
630: discharge port 640: orifice hole
700: rotating shaft 800: swash plate
900: Piston

Claims (5)

A cylinder block 300 in which a center bore 310 is formed at a center and a plurality of cylinder bores 320 are formed at a radially outer side of the center bore 310 in the circumferential direction to be spaced apart from each other;
A front housing 400 coupled to the front of the cylinder block 300 and having a crank chamber 410 formed therein;
A rear housing 500 coupled to the rear of the cylinder block 300 and having a suction chamber 510 and a discharge chamber 520 formed therein;
A rotating shaft (700) rotatably installed through the center of the front housing (400) and the cylinder block (300);
A swash plate 800 coupled to the rotating shaft 700 through a central portion thereof so as to rotate integrally with the rotating shaft 700 and slantly installed in the crank chamber 410;
A plurality of pistons 900 coupled to one side of the swash plate 800 to reciprocate linearly by rotation of the swash plate 800;
A first communication path (331) formed at one side of the cylinder block (300) to communicate with the crank chamber (410);
A spool chamber (330) formed at the rear of the center bore (310) to communicate with the suction chamber (510) and communicating with the first communication path (331);
And a spool valve (340) installed in the spool chamber (330) and elastically supported at a rear end of the rotating shaft (700) and opening / closing the first communication path (331)
And a second communication path (332) communicating the discharge chamber (520) and the spool chamber (330) is formed on the other side of the cylinder block (300).
delete The method according to claim 1,
A valve plate 600 is interposed between the cylinder block 300 and the rear housing 500 and one side of the first communication path 331 is connected to an orifice hole 640 formed in the valve plate 600 And the suction chamber (510) is communicated with the suction chamber (510).
The method of claim 3,
And the diameter of the first communication path (331) is 2.5 mm to 20 mm.
The method according to claim 1,
A valve plate (600) is interposed between the cylinder block (300) and the rear housing (500)
The spool valve (340)
A head portion 343 having one end supported by the valve plate 600 and the other end supported by the elastic member 341 and facing the rear end of the rotation shaft 700; And an opening / closing part (344) formed to extend along the rim of the spool chamber (330) to closely contact the side wall of the spool chamber (330) and open / close the first communication path (331).

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