COMPRESSOR

Abstract

Disclosed is a compressor in which, in correspondence to a point in time that the piston is reached to a bottom dead center to start compression of the refrigerant, the outlet of the main refrigerant suction channel is closed by an inner wall of the cylinder block so that the inlet of the suction passageway of the cylinder block and the outlet of the main refrigerant suction channel of the drive shaft are discommunicated.

Description

RELATED APPLICATIONS

The present application is based on, and claims priority from, KR Application Number 10-2007-0054067, filed Jun. 01, 2007, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a compressor, and more particularly to a compressor that is a fixed capacity swash plate type compressor in which a piston reciprocates depending on rotation of a swash plate integrally coupled to a drive shaft and employs a rotary suction valve structure in which refrigerant inhaled into the inside of the drive shaft from a swash plate chamber is sequentially inhaled into respective cylinder bore according to the rotation of the drive shaft.

2. Description of the Related Art

In general, a compressor inhales refrigerant gas discharged from an evaporator after complete evaporation; converts the refrigerant gas into easily liquefiable refrigerant gas at high temperature and high pressure; and then discharges the refrigerant gas to a condenser. This compressor is divided into various kinds, such as a swash plate type compressor in which a piston reciprocates by rotation of an inclined swash plate, a scroll type compressor which compresses by rotation of two scrolls, a rotary vane type compressor which compresses by rotary vane and so on.

The reciprocating compressor which compresses the refrigerant according to reciprocating of the piston includes, besides the swash plate type compressor, a crank type compressor, a wobble plate type compressor, etc., and the swash plate type compressor is divided, according to its use, into a fixed capacity swash plate type compressor, a variable capacity swash plate type compressor, etc.

FIG. 1 shows a conventional compressor, which is an example of a fixed capacity swash plate type compressor and employs a rotary suction valve structure.

As shown, the conventional compressor 1 is provided with front and rear housings 10 and 11, cylinder blocks 20 and 21 coupled to the inside of the front and rear housings 10 and 11 and formed with an inside swash plate chamber 22 and a plurality of cylinder bores 23, a drive shaft 30 to which a swash plate 31 rotating in the swash plate chamber is integrally coupled with an inclination, a plurality of pistons 40 reciprocating in the inside of the cylinder bore 23 depending on the rotation of the swash plate 31 and valve units 50 and 51 respectively interposed between the front and rear housings 10 and 11 and the cylinder blocks 20 and 21.

Also, a main refrigerant suction channel 32 is formed inside the drive shaft 30 so that the refrigerant inhaled from the swash plate chamber 22 can move to the cylinder bore 23, and a plurality of suction passageways 25 and 26 which communicate the main refrigerant suction channel 32 and respective cylinder bores 23 are formed in the cylinder blocks 20 and 21.

A detailed circulation process in the conventional fixed capacity swash plate type compressor employing the rotary suction valve structure as describe above is as follows.

Firstly, the refrigerant is supplied from the outside to the inside of the swash plate chamber 22, and the refrigerant supplied to the swash plate chamber 22 is sequentially supplied to respective cylinder bores 23 through the main refrigerant suction channel 32 formed in the inside of the drive shaft 30 and the suction passageways 25 and 26 of the cylinder blocks 25 and 26 when the drive shaft 30 rotates.

An inlet 33 of the main refrigerant suction channel 32 of the drive shaft 30 is directly communicates with the swash plate chamber 22, and a suction chamber 60 which communicates to the main refrigerant suction channel 32 is formed in rear of the cylinder block 21. The inlet 33 of the main refrigerant suction channel 32 may be formed so as to pass through a hub 31a of the swash plate 31 and the one side of the drive shaft 30.

Meanwhile, FIG. 2A is a cross-sectional view taken along line II-II in FIG. 1, in which a No. 3 piston is reached to the bottom dead center to start compression, and FIG. 2B is a conceptual view illustrating the state of FIG. 2A.

As shown, the suction passageway 26 of the cylinder block 21 has a width W. Also, an end 34a of the outlet 34 of the main refrigerant suction channel 32 is located on a centerline C1-C1 of a section of the suction passageway 26 when viewed in reference to a clockwise direction of the drive shaft 30. Herein, an alphanumeral A1 denotes an opening angle of the outlet 34 of the main refrigerant suction channel 32.

Therefore, the suction passageway 25 of the cylinder block 20 and the outlet 34 of the main refrigerant suction channel 32 in the drive shaft 30 are not discommunicated, but come to be communicated to each other at the point in time at which the piston 40 is reached to start compression. Herein, an alphanumeral B denotes an area in which the suction passageway 25 and the main refrigerant suction channel 32 are communicated to each other.

In other words, the suction passageway 25 and inlet 34 of the main refrigerant suction channel 32 come to be communicated to each other at the point in time at which the piston 40 is reached to start compression, thereby consequently lowering a suction efficiency.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a compressor having an improved structure so as to improve a suction efficiency of refrigerant by controlling the point in time at which the refrigerant is inhaled into a cylinder bore.

To achieve the above and other objects, the present invention provides a compressor in which a swash plate rotating in a swash plate chamber formed in the inside of a cylinder block is integrally coupled to a drive shaft, pistons respectively received in the insides of a plurality of cylinder bores annularly arranged at a periphery of the drive shaft reciprocate depending on the rotation of the swash plate, and refrigerant inhaled into a main refrigerant suction channel formed inside of the drive shaft from the swash plate is inhaled into the respective cylinder bores through a plurality of suction passageways formed in the cylinder block so as to sequentially communicate the main refrigerant suction channel and the respective cylinder bores according to the rotation of the drive shaft, wherein, in correspondence to a point in time that one of the pistons is reached to a bottom dead center to start compression of the refrigerant, the outlet of the main refrigerant suction channel is closed by an inner wall of the cylinder block so that the inlet of the suction passageway of the cylinder block and the outlet of the main refrigerant suction channel of the drive shaft are discommunicated.

Preferably, an end of the outlet of the main refrigerant suction channel is located on the inner wall of the cylinder block between one suction passageway corresponding to the piston and another adjacent suction passageway in reference with the rotation direction of the drive shaft at the point in time that the piston is reached to the bottom center.

Preferably, an end of the outlet of the main refrigerant suction channel corresponds to an end portion of the suction passageway of the cylinder block in the rotation direction of the drive shaft at the point in time that the piston is reached to the bottom dead center.

Further, a sectional centerline of the suction passageway formed in the cylinder block could be inclined by a predetermined angle in the rotation direction of the drive shaft with respect to a plane including a centerline of the cylinder bore and an axial centerline of the drive shaft.

The piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber, the outlet of the main refrigerant suction channel of the drive shaft is formed at least one in every front and rear so as to correspond to the cylinder bores in front and rear, and a refrigerant communication passageway communicating the swash plate chamber and the inlet of the main refrigerant suction channel of the drive shaft is formed in the swash plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of an example of a conventional compressor.

FIG. 2A is a cross-sectional view taken along line II-II in FIG. 1, in which a No. 3 piston is reached to the bottom dead center to start compression.

FIG. 2B is a conceptual view illustrating the state of FIG. 2A.

FIG. 3 is an exploded perspective view showing a compressor according to an embodiment of the present invention.

FIG. 4 is sectional view of the compressor in FIG. 3.

FIG. 5A is a cross-sectional view taken along line V-V in FIG. 3, in which a No. 3 piston is reached to the bottom dead center to start compression.

FIG. 5B is a conceptual view illustrating the state of FIG. 6A.

FIG. 6A is a cross-sectional view showing a compressor according to another embodiment of the present invention, in which a No. 3 piston is reached to the bottom dead center to start compression.

FIG. 6B is a conceptual view illustrating the state of FIG. 6A.

BEST MODE FOR CARRYING OUT THE INVENTION

Practical and presently preferred embodiments of the present invention are illustrative as shown in the following Examples and Comparative Examples.

However, it will be appreciated that those skilled in the art, on consideration of this disclosure, may make modifications and improvements within the spirit and scope of the present invention.

FIG. 3 is an exploded perspective view showing a compressor according to a preferred embodiment of the present invention, and FIG. 4 is sectional view of the compressor in FIG. 3.

As shown, a compressor 100 according to an embodiment of the present invention is provided with a drive shaft 140 to which a swash plate 150 rotating in a swash plate chamber 132 is integrally coupled; front and rear cylinder blocks 130 and 131 in which the drive shaft 140 is rotatably installed; a plurality of pistons 160 which are mounted at an outer periphery of the swash plate 150 with a shoe 144 interposed therebetween and reciprocate in the insides of the cylinder bores 130a and 131a formed at both sides of the swash plate chamber 132 of the front and rear cylinder blocks 130 and 131; front and rear housings 110 and 120 which are coupled to both sides of the front and rear cylinder blocks 130 and 131 and respectively formed with discharge chambers 111 and 121; and valve units 170 and 180 which are respectively interposed between front and rear cylinder blocks 130 and 131 and the front and rear housings 110 and 120.

The swash plate 150 rotating in the swash plate chamber 132 is coupled with inclination to the drive shaft 140, and a main refrigerant suction channel 141, which communicates the swash plate chamber 132 and the cylinder bores 130a and 131a so that the refrigerant inhaled into the swash plate chamber 132 transfers to the cylinder bores 130a and 131a through the swash plate 150, is formed in the inside of the drive shaft 140. In other words, an inlet 142 of the main refrigerant suction channel 141 is formed so as to communicate with the swash plate chamber 132, and an outlet 143 thereof is formed so as to communicate respective suction passageways 135 of the front and rear cylinder blocks 130 and 131.

The inlet 142 of the main refrigerant suction channel 141 communicates with the swash plate chamber through a refrigerant communication passageway 151 formed thorough the hub 150a of the swash plate 150 and one side of the drive shaft 140. Herein, only one inlet 142 of the main refrigerant suction channel 141 may be formed at a side of the drive shaft 140 or two inlets 142 may be formed in opposite directions to each other.

The outlet 143 of the main refrigerant suction channels 141 are formed at both sides of the main refrigerant suction channels 141 in opposite directions to each other to allow the refrigerant to be simultaneously inhaled into respective cylinder bores 130a and 131a formed at both sides of the swash plate chamber 132 when the driving 140 shaft rotates. That is to say, since the pistons 160 disposed in opposite directions to each other in the pistons 160 coupled to the outer periphery of the swash plate 150 performs the same suction or compression stroke as the swash plate 150 is inclined, both outlets 143 of the main refrigerant suction channel 141 should be formed in the opposite directions to each other to allow the refrigerant to be simultaneously inhaled into the cylinder bores 130a and 131a formed at both sides of the swash plate chamber 132. Of course, directions of the respective outlets 143 of the main refrigerant suction channel 141 formed in the drive shaft 140 may be varied as a design requirement such as a number of the piston 160.

Through the main refrigerant suction channel 141 formed in the drive shaft 140, the refrigerant in the swash plate chamber 132 is supplied to the insides of the cylinder bores 130a and 131a. At this time, in order that sufficient amount of the refrigerant can be supplied even when the drive shaft rotates in high speed, a refrigerant undercurrent chamber 190 may be additionally formed in rear of the cylinder block and an auxiliary refrigerant suction passageway 191 which communicates the swash plate chamber 132 and the refrigerant undercurrent chamber 190 may be additionally formed in the cylinder block 131. Therefore, when the drive shaft 140 rotates in high speed, the refrigerant in the swash plate chamber 132 is supplied to the insides of the cylinder bores 130a and 131a through the auxiliary refrigerant suction passageway 191 as well as the main refrigerant suction channel 141. Consequently, sufficient amount of the refrigerant is supplied to improve the performance.

In the compressor of the present invention constructed as described above, a preferred embodiment of the present invention will be described with reference to FIGS. 3 through 5B. FIG. 5A is a cross-sectional view taken along line V-V in FIG. 3, in which a No. 3 piston 160 is reached to the bottom dead center to start compression, and FIG. 5B is a conceptual view illustrating the state of FIG. 6A. Herein, a description will be made based on a point in time at which the No. 3 piston 160 is reached to the bottom dead center to start the compression of the refrigerant, it will be apparent that this principle may be identical with respect to the point in time at which other pistons (In FIG. 5a, No. 1, 2, 4 and 5 pistons) are reached to the bottom dead center to start the compression of the refrigerant.

To improve a suction efficiency of the refrigerant, the inlet of the suction passageway 135 of the cylinder block 130 and the outlet 143 of the main refrigerant suction channel 141 of the drive shaft 140 should be discommunicated in correspondence to the point in time at which the No. 3 piston 160 is reached to the bottom dead center to start the compression of the refrigerant.

To this end, as shown in FIGS. 5A and 5B, when viewed in reference to rotation direction of the drive shaft 140 (clockwise direction) at the point in time at which the piston 160 is reached to the bottom dead center, the end 143a of the outlet 143 of the main refrigerant suction channel 141 is formed at a location which is moved in the rotation direction of the drive shaft 140 (clockwise direction) from the sectional centerline C3-C3 of the suction passageway 135 of the cylinder block 130.

Herein, the sectional centerline C3-C3 of the suction passageway 135 of the cylinder block 130 is a centerline of the section (section V-V; FIG. 3) obtained by cutting the suction passageway 135 of the cylinder block 130 in a plane perpendicular to the drive shaft 140. Also, the sectional centerline C3-C3 should be placed on a plane (P in FIG. 3) including a centerline of the cylinder bore 130a and an axial centerline C-C of the drive shaft 140. Herein, an alphanumeral A2 denotes an opening angle of the outlet 143 of the main refrigerant suction channel 141.

By doing this, an inner wall of the cylinder block 130 comes to block the outlet 143 of the main refrigerant suction channel 141 of the drive shaft 140 at the point in time at which the piston 160 is reached to the bottom dead center, and thus the suction passageway 135 of the cylinder block 130 and the he outlet 143 of the main refrigerant suction channel 141 of the drive shaft 140 are discommunicated.

Hereinafter, a compressor according to another embodiment of the present invention will be described. FIG. 6A is a cross-sectional view showing a compressor 200 according to another embodiment of the present invention, in which a No. 3 piston 260 (hereinafter, referred to as ‘piston’) is reached to the bottom dead center to start compression. Herein, alphanumerals identical to the alphanumerals shown in FIGS. 3 and 4 denote identical members having identical structure and function, and thus the identical description will not be repeated. Also, the structure and function identical to that of the aforementioned embodiment will not be described and only different structure and function will be described.

Referring to FIGS. 3, 4, 6A and 6B, to discommunicate the inlet of the suction passageway 135 of the cylinder block 230 and the outlet 243 of the main refrigerant suction channel 241 of the drive shaft 240 at the point in time at which the piston 260 is reached to the bottom dead center to start the compression of the refrigerant, the sectional centerline C4-C4 of the suction passageway 235 formed in the cylinder bores 230 and 231 may be inclined by a predetermined angle in the rotation direction of the drive shaft 240 with respect to the plane P including the centerline C2-C2 of the cylinder bore 230a and the axial centerline C-C of the drive shaft 240. Herein, an alphanumeral A3 denotes an opening angle of the outlet 243 of the main refrigerant suction channel 241.

Though, in the embodiments of the present invention described above, the piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber and the main refrigerant suction channel is respectively formed at least one in every front and rear so as to correspond to the respective cylinder bores in front and rear, these are merely exemplary and the characteristics of the present invention may also be adopted to a fixed capacity swash plate type compressor which is provided with a single headed piston and employs a rotary suction valve structure.

Also, though the inlet 142, 242 of the main refrigerant suction channel 141, 241 formed in the inside of the drive shaft is formed through the hub 150a of the swash plate 150 and one side of the drive shaft 140, 240 in the embodiments of the present invention, the characteristics of the present invention may also be adopted to a compressor in which the inlet 33 of the main refrigerant suction channel 32 is formed in such a manner that the one side of the drive shaft 30 communicates directly with the swash plate chamber 22 and the suction chamber 50 communicating with the main refrigerant suction channel 32 is formed in rear of the cylinder block 21 as shown in FIG. 1.

INDUSTRIAL APPLICABILITY

According to the compressor of the present invention as described above, since the outlet of the main refrigerant suction channel of the drive shaft and the suction passageway of the cylinder block is discommunicated at the same point in time as the point in time at which the piston is reached to the bottom dead center to start compression, it is possible to improve a suction efficiency of the refrigerant.

Those skilled in the art will appreciate that the conceptions and specific embodiments disclosed in the foregoing description may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. Those skilled in the art will also appreciate that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended claims.

Claims

1. A compressor including: a cylinder block;a swash plate rotating in a swash plate chamber formed in the inside of the cylinder block and integrally coupled to a drive shaft;pistons respectively received in the insides of a plurality of cylinder bores annularly arranged at a periphery of the drive shaft and reciprocating by the rotation of the swash plate;a main refrigerant suction channel formed inside of the drive shaft; anda plurality of suction passageways formed in the cylinder block so as to sequentially communicate the main refrigerant suction channel and the respective cylinder bores where refrigerant inhaled into the main refrigerant channel is inhaled according to the rotation of the drive shaft;wherein, in correspondence to a point in time that one of the pistons is reached to a bottom dead center to start compression of the refrigerant, the outlet of the main refrigerant suction channel is closed by an inner wall of the cylinder block so that the inlet of the suction passageway of the cylinder block and the outlet of the main refrigerant suction channel of the drive shaft are discommunicated.

2. The compressor as set forth in claim 1, wherein an end of the outlet of the main refrigerant suction channel is located on the inner wall of the cylinder block between one suction passageway corresponding to the piston and another adjacent suction passageway in reference with the rotation direction of the drive shaft at the point in time that the piston is reached to the bottom dead center.

3. The compressor as set forth in claim 2, wherein an end of the outlet of the main refrigerant suction channel corresponds to an end portion of the suction passageway of the cylinder block in the rotation direction of the drive shaft at the point in time that the piston is reached to the bottom dead center.

4. The compressor as set forth in claim 2, wherein a sectional center-line of the suction passageway formed in the cylinder block is inclined by a predetermined angle in the rotation direction of the drive shaft with respect to a plane including a center-line of the cylinder bore and an axial center-line of the drive shaft.

5. The compressor as set forth in claim 1, wherein the piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber, the outlet of the main refrigerant suction channel of the drive shaft is formed at least one in every front and rear so as to correspond to the cylinder bores in front and rear of the drive shaft, anda refrigerant communication passageway communicating the swash plate chamber and the inlet of the main refrigerant suction channel of the drive shaft is formed in the swash plate.

6. The compressor as set forth in claim 2, wherein the piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber, the outlet of the main refrigerant suction channel of the drive shaft is formed at least one in every front and rear so as to correspond to the cylinder bores in front and rear of the drive shaft, anda refrigerant communication passageway communicating the swash plate chamber and the inlet of the main refrigerant suction channel of the drive shaft is formed in the swash plate.

7. The compressor as set forth in claim 3, wherein the piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber, the outlet of the main refrigerant suction channel of the drive shaft is formed at least one in every front and rear so as to correspond to the cylinder bores in front and rear of the drive shaft, anda refrigerant communication passageway communicating the swash plate chamber and the inlet of the main refrigerant suction channel of the drive shaft is formed in the swash plate.

8. The compressor as set forth in claim 4, wherein the piston is a double headed piston, the cylinder bore is formed in plural at both sides of the swash plate chamber, the outlet of the main refrigerant suction channel of the drive shaft is formed at least one in every front and rear so as to correspond to the cylinder bores in front and rear of the drive shaft, anda refrigerant communication passageway communicating the swash plate chamber and the inlet of the main refrigerant suction channel of the drive shaft is formed in the swash plate.