Compressor

Abstract

 A compressor capable of attenuating shock and noise caused when compressed gas is bypassed into a suction space (13) for the control of compression capacity thereof. The compressor includes a bypass passage (65) to bypass the compressed gas into the suction space (13), a shut off valve (66) to open or close the bypass passage (65), and a noise attenuating device (80) mounted to the bypass passage (65) downstream of the valve (66) and having a gas storage space (82) to store a certain amount of gas.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from Korean Patent Application No. 2005-59686, filed on July 4, 2005 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0002] The present invention relates to a compressor and, more particularly, to a compressor capable of attenuating noise caused when compressed gas is bypassed into a suction space for controlling a compressor capacity.

2. Description of the Related Art

[0003] U.S. Pat. No. 6,745, 584 discloses an example of a compressor designed to bypass compressed gas into a suction space thereof to thereby control a compression capacity.

[0004] The compressor disclosed in the above publication is a scroll compressor having a variable compression capacity. The scroll compressor comprises a bypass tube to bypass compressed gas from a compression chamber into a suction space of the compressor, and a shut off valve to open or close the bypass tube. Typically, the compression capacity of the scroll compressor increases when the compressor is operated in the closed position of the shut off valve. Conversely, the capacity of the compressor decreases when the valve is moved to its open position to bypass the compressed gas into the suction space. In this way, the compression capacity of the compressor is controllable on demand.

[0005] However, the above-described compressor suffers from a wide pressure difference between the compressed gas, bypassed into the suction space by way of the bypass tube, and suction gas in the suction space. As the high-pressure gas flows into the suction space through the open valve for controlling the compression capacity of the compressor, it tends to generate excessive shock and noise. The shock and noise may be transmitted to peripheral elements through tubes, and may cause discomfort in the use of the compressor because it is louder than normal operational noise of the compressor.

SUMMARY OF THE INVENTION

[0006] Therefore, the present invention has been made in order to improve functions of the conventional compressor as mentioned above, and it is an aspect of the invention to provide a compressor capable of attenuating shock and noise caused when compressed gas is bypassed into a suction space of the compressor.

[0007] Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention.

[0008] In accordance with one aspect, the present invention provides a compressor comprising: a bypass passage to bypass compressed gas into a suction space, a shut off valve to open or close the bypass passage, and a noise attenuating device mounted to the bypass passage downstream of the shut off valve and having a gas storage space to store the gas.

[0009] The noise attenuating device may further have a casing provided with an inlet in communication with the bypass passage, an interior volume of the casing being varied by the gas that is discharged from the compressor and bypassed via the bypass passage.

[0010] The noise attenuating device may further have a partition member reciprocably mounted in the casing, and a spring to push the partition member toward the inlet of the casing.

[0011] The noise attenuating device may further have a dampening member affixed to an inner wall surface of the casing to attenuate noise caused when the partition member comes into contact with the inner wall surface of the casing.

[0012] The noise attenuating device may further have an air-tightness seal mounted on an outer circumference of the partition member.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a longitudinal sectional view of a compressor consistent with the present invention, shown in the closed state of a shut off valve;

FIG. 2 is a longitudinal sectional view of the compressor of FIG. 1, shown in the open state of the shut off valve;

FIG. 3 is a system diagram of a refrigeration system using the compressor consistent with the present invention; and

FIG. 4 is a sectional view of a noise attenuating device provided in the compressor consistent with the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE, NONLIMITING EMBODIMENTS OF THE INVENTION

[0014] Reference will now be made in detail to the illustrative, non-limiting embodiment of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The exemplary embodiment is described below to explain the present invention by referring to the figures.

[0015] FIG. 1 is a longitudinal sectional view of a compressor consistent with the present invention. As shown in FIG. 1, the compressor consistent with the present invention comprises a hermetic container 10, a scroll compression unit 20 mounted in an upper region of the hermetic container 10, a drive unit 40 mounted in a lower region of the hermetic container 10 to drive the scroll compression unit 20, and a rotary shaft 50 to transmit a rotating force of the drive unit 40 to the scroll compression unit 20.

[0016] The drive unit 40 includes a cylindrical stator 41 affixed to an inner wall surface of the hermetic container 10, and a rotor 42 rotatably mounted in the stator 41 to be coupled on the rotary shaft 50 that penetrates the center of the rotor 42.

[0017] The scroll compression unit 20 includes a bearing housing 21 affixed to the inner wall surface of the hermetic container 10 and adapted to rotatably support an upper portion of the rotary shaft 50, a non-orbiting scroll member 22 disposed above the bearing housing 21 in a vertically movable manner and having a spiral first vane 23, and an orbiting scroll member 24 coupled to an underside of the non-orbiting scroll member 22 to move in an orbit and having a spiral second vane 25 positioned in mesh engagement with the first vane 23 of the non-orbiting scroll member 22 to perform compression of gas.

[0018] The orbiting scroll member 24 is connected, at a lower portion thereof, to an eccentric shaft 51 by interposing a rotary bush 52. Here, the eccentric shaft 51 is connected to an upper end of the rotary shaft 50. A rotation-proof unit 26 is interposed between a lower surface of the orbiting scroll member 24 and the bearing housing 21. The rotation-proof unit 26 takes the form of an Oldham coupling and serves to move the scroll member 24 in an orbit while preventing rotation thereof. As the orbiting scroll member 24 orbits during rotation of the rotary shaft 50, the second vane 25 also orbits with respect to the spiral first vane 23, allowing the gas between the first and second vanes 23 and 25 to be compressed.

[0019] The interior space of the hermetic container 10 is divided into an upper discharge space 12 and a lower suction space 13 by a partition plate 11 that is mounted at the top of the non-orbiting scroll member 22. Also, the scroll compression unit 20 is provided with a suction port 27 to allow refrigerant gas to be suctioned into the scroll compression unit 20 and a discharge port 28 to allow the compressed gas to be discharged from the scroll compression unit. The suction port 27 is formed at an outer circumference of the non-orbiting scroll member 22 to be in communication with the suction space 13. The discharge port 28 is centrally formed at the top of the non-orbiting scroll member 22 to be in communication with the discharge space 12. The discharge port 28 is provided with a lid type shut off valve 29. In operation, as the intermeshing first and second vanes 23 and 25 move radially inwardly as a result of the orbiting motion of the scroll member 24, suction gas is suctioned from the suction space 13 into the scroll compression unit 20 through the suction port 27, and is compressed into the high-pressure compressed gas. The compressed gas is then discharged into the discharge space 12 through the discharge port 28.

[0020] In the present invention, a discharge tube 14 is connected to an upper location of the hermetic container 10 to discharge the refrigerant gas of the discharge space 12, while a suction tube 15 is connected to a lower location of the hermetic container 10 to introduce the low-pressure refrigerant gas into the suction space 13. Referring to FIG. 3 showing a refrigeration system, when the high-pressure refrigerant gas is discharged out of the hermetic container 10 through the discharge tube 14, it successively passes through a condenser 1 that liquefies the compressed refrigerant gas, an expander 2 that depressurizes and expands the liquid refrigerant, and an evaporator 3 that evaporates the resulting refrigerant into low-pressure gas. The low-pressure gas is again introduced into the suction space 13 of the hermetic container 10 through the suction tube 15.

[0021] The compressor consistent with the present invention further comprises a capacity control device 60 to control a compression capacity of the compressor. For this, the capacity control device 60 is designed to bypass the compressed gas into the suction tube 15 and, simultaneously, to move the non-orbiting scroll member 22 upward.

[0022] The capacity control device 60 includes a cylinder member 62 mounted in an uppermost portion of the hermetic container 10 to define a compression chamber 61, a piston 63 mounted to vertically reciprocate in the cylinder member 62, and a connecting member 64 to connect the piston 63 to the top of the non-orbiting scroll member 22. The capacity control device 60 further includes a bypass tube 65 extending between the compression chamber 61 and the suction tube 15 to discharge the gas from the compression chamber 61 into the suction tube 15, and a shut off valve 66 to open or close the bypass tube 65.

[0023] The connecting member 64 has a discharge passage 71 to guide the compressed gas, discharged through the discharge port 28 of the non-orbiting scroll member 22, into the discharge space 12. The connecting member 64 also has an orifice 72 provided in an upper portion thereof to introduce the compressed gas of the discharge space 12 into the compression chamber 61.

[0024] The non-orbiting scroll member 22 is formed in an upper portion thereof with an annular groove 73 around the connecting member 64. A vertically movable sealing member 74 is inserted in the annular groove 73. The sealing member 74 seals the top of the non-orbiting scroll member 22 from the partition plate 11 to intercept passage of the gas between the suction space 13 and the discharge space 12. The non-orbiting scroll member 22 is also formed with an intermediate passage 75 to guide the gas into the annular groove 73 during compression. With this configuration, even if the non-orbiting scroll member 22 is vertically moved, the non-orbiting scroll member 22 is kept in an air tight state relative to the partition plate 11.

[0025] Therefore, as shown in FIG. 1, when the compressor consistent with the present invention is operated in the closed position of the shut off valve 66, the gas of the discharge space 12 is introduced into the compression chamber 61 through the orifice 72 of the connecting member 64, whereby the pressure of the compression chamber 61 increases. Thereby, the piston 63 and the connecting member 64 are moved downwardly, and, also, the non-orbiting scroll member 22 connected to the connecting member 64 is moved downwardly. In this case, the non-orbiting scroll member 22 and the orbiting scroll member 24 operate in meshing engagement with each other, allowing the compressor to operate at 100% capacity.

[0026] Also, as shown in FIG. 2, when the compressor consistent with the present invention is operated in the open position of the shut off valve 66, the gas of the compression chamber 61 is discharged into the suction tube 15 through the bypass tube 65, whereby the pressure of the compression chamber 61 decreases. Thereby, the piston 63 and the connecting member 64 are moved upwardly due to a pressure difference between the discharge space 12 and the compression chamber 61, and, also, the non-orbiting scroll member 22 is moved upwardly. With this upward movement of the non-orbiting scroll member 22, a gap 77 is created between the non-orbiting scroll member 22 and the orbiting scroll member 24, allowing the scroll compression unit 20 to operate in a substantially no load state. In this way, the present invention is able to control the compression capacity of the compressor through the control of opening and closing operations of the shut off valve 66.

[0027] Meanwhile, to attenuate shock and noise caused when the refrigerant gas is bypassed through the open valve 66, the compressor consistent with the present invention further comprises a noise attenuating device 80 mounted to the bypass tube 65 downstream of the valve 66. As shown in FIG. 4, the noise attenuating device 80 includes a casing 81 defining a gas storage space 82 to contain a certain amount of gas. The casing 81 is formed with an inlet 83 to communicate with the tube 65. The noise attenuating device 80 further includes a partition member 84 that is mounted in the casing 81 in a vertically reciprocable manner to vary the volume of the gas storage space 82 depending on the pressure of the gas bypassed by the bypass tube 65, and a spring 85 mounted in the casing 81 to push the partition member 84 toward the inlet 83 of the casing 81.

[0028] The noise attenuating device 80 further includes a dampening member 86, and a seal 87. The dampening member 86 is affixed to an inner wall surface of the casing 81 at a position close to the inlet 83. The dampening member 86 serves to prevent generation of noise when the partition member 84 comes into contact with the inner wall surface of the casing 81 during reciprocating movement thereof. The seal 87 is mounted to an outer circumference of the casing 81 to prevent passage of the gas through a gap between the partition member 84 and the inner wall surface of the casing 81.

[0029] Now, the operation of the noise attenuating device 80 will be explained.

[0030] When the compressor is operated in the closed position of the valve 66, as shown in FIG. 1, the compressed gas of the compression chamber 61 is not directed into the bypass tube 65. In this case, the partition member 84 is kept at an upwardly moved state close to the inlet 83 by the elasticity of the spring 85, resulting in reduction in the volume of the gas storage space 82.

[0031] Conversely, when the shut off valve 66 is opened to reduce the compression capacity of the compressor, as shown in FIG. 2, since the compressed gas of the compression chamber 61 is introduced into the gas storage space 82 of the casing 81 through the bypass tube 65, the partition member 84 is pushed by the pressure of the compressed gas, resulting in increase in the volume of the gas storage space 82. As a result, the compressed gas is able to be temporarily stored in the gas storage space 82 of the casing 81, effectively attenuating shock waves applied to the bypass tube 65 when the valve 66 is moved to its open position by the compressed gas. Specifically, since the gas storage space 82 increases in volume as the partition member 84 is pushed by the pressure of the compressed gas, the compressed gas, having passed through the bypass tube 65, is able to be temporarily stored in the gas storage space 82, acting to absorb shock waves caused when the valve 66 is moves to the open position. This has the effect of preventing generation of noise. In succession, the compressed gas is gradually discharged from the gas storage space 82 to thereby be directed into the suction tube 15. In this case, the partition member 84 is returned to the upwardly moved state as shown in FIG. 1 by the elasticity of the spring 85.

[0032] As is apparent from the above description, the present invention provides a compressor wherein compressed gas, which is bypassed via a bypass tube, is temporarily stored in a gas storage space of a noise attenuating device, thereby attenuating noise and shock caused when the compressed gas is introduced into a suction space of the compressor.

[0033] Although exemplary embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

Claims

1. A compressor comprising:

a bypass passage to bypass compressed gas into a suction space,

a shut-off valve to open or close the bypass passage, and

a noise attenuating device mounted to the bypass passage downstream of the shut-off valve and having a gas storage space to store the gas.

2. The compressor according to claim 1, wherein the noise attenuating device further has a casing provided with an inlet in communication with the bypass passage, an interior volume of the casing being varied by the gas that is discharged from the compressor and bypassed via the bypass passage.

3. The compressor according to claim 2, wherein the noise attenuating device further has a partition member reciprocably mounted in the casing, and a spring to push the partition member toward the inlet of the casing.

4. The compressor according to claim 3, wherein the noise attenuating device further has a dampening member affixed to an inner wall surface of the casing to attenuate noise caused when the partition member comes into contact with the inner wall surface of the casing.

5. The compressor according to claim 3, wherein the noise attenuating device further has an air-tightness seal mounted on an outer circumference of the partition member.

Drawing