JP2010127071A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of causing the performance deterioration and the reliability deterioration, when a thrust load increases since excessive back pressure is applied on a turning scroll, when excessive oil is supplied to a back pressure chamber from a high pressure area, in a scroll compressor for controlling back pressure by intermittently communicating the back pressure chamber with a compression space. <P>SOLUTION: The stable back pressure is applied since the excessive oil 6 is not supplied to the back pressure chamber 29, by intermittently making the oil enter the back pressure chamber 29 from the high pressure area 30 and to the compression space 15 from the back pressure chamber 29. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a scroll compressor used in a cooling device such as a cooling / heating air conditioner or a refrigerator, or a heat pump type hot water supply device.

  Conventionally, scroll compressors used in cooling devices such as air-conditioning and air-conditioning systems and refrigerators generally have a compression chamber formed by meshing a fixed scroll and a rotating scroll where a spiral wrap rises from the end plate, and the rotating scroll is restrained from rotating. When swung along a circular orbit under the restraint of rotation by the mechanism, the compression chamber moves while changing its volume, thereby performing suction, compression, and discharge. The working fluid is gradually compressed along with the turning motion of the orbiting scroll, and becomes a high pressure state toward the center portion. As a result, a gap is generated between the orbiting scroll and the fixed scroll, so that leakage occurs during compression, resulting in performance deterioration. As a countermeasure, there is a method in which an intermediate pressure is applied to the back of the orbiting scroll to prevent separation from the fixed scroll (see, for example, Patent Document 1).

FIG. 4 is a longitudinal sectional view of a compression mechanism portion of a conventional scroll compressor described in Patent Document 1. Provided on the end plate of the orbiting scroll 3 is provided with a communication passage 22 that communicates from the compression chamber side opening 22c that opens to the compression chamber 14 side to the back pressure chamber side opening 22b that opens to the back pressure chamber 12, and the orbiting scroll 3 With the swivel motion, the communication chamber 22 is communicated and closed by opening and closing the compression chamber side opening 22c by the end plate of the fixed scroll 2. By this communication and closing operation, the pressure in the back pressure chamber 12 is maintained at a predetermined pressure (= intermediate pressure).
JP 2007-270697 A

  However, the conventional configuration does not disclose any oil supply to the back pressure chamber 12. Since the rotation restraint mechanism 8 represented by the Oldham ring is arranged in the back pressure chamber 12, oil for lubrication is required, but usually the oil in the oil reservoir is guided to the back pressure chamber 12. And supply. However, since the oil in the oil reservoir is in a high pressure state, if a large amount of oil is supplied, the pressure in the back pressure chamber 12 becomes high, and an excessive back pressure may be applied to the orbiting scroll 3. When an excessive back pressure is applied, the thrust load increases, so that there is a problem of causing performance deterioration and reliability deterioration.

  The present invention solves the above-described conventional problems, and restricts the communication timing of the high pressure region and the back pressure chamber, and the back pressure chamber and the compression chamber, thereby preventing excessive back pressure and stable back pressure. Since it is possible to control the oil supply amount from the high pressure area to the back pressure chamber by the communication ratio, there is no need for throttling by pores, etc., that is, the problem of foreign matter biting and blockage can be solved, An object of the present invention is to provide a scroll compressor that realizes high efficiency and high reliability.

In order to solve the above-described conventional problems, a scroll compressor according to the present invention forms a compression chamber between the fixed scroll and the orbiting scroll in which the spiral wrap rises from the end plate, and seals the back of the orbiting scroll. By arranging the members, a high pressure region and a back pressure chamber are formed, and the orbiting scroll revolves with a predetermined orbiting radius along the circular orbit by regulation by the rotation restraint mechanism, so that the compression chamber moves toward the center while changing the volume. A scroll compressor that performs a series of operations of suction, compression, and discharge, provided with a first path that communicates from the high pressure region to the back pressure chamber through the inside of the orbiting scroll. On the thrust surface of the fixed scroll, there is a second path that allows the back pressure chamber side opening end to communicate intermittently by moving the seal member and to communicate with only one of the back pressure chamber and the compression chamber. Provided, in which the back pressure chamber side opening end of the second path was intermittently back pressure chamber and communicated by the turning of the orbiting scroll.

  According to this configuration, excessive back pressure can be prevented and stable back pressure can be applied. In addition, since the amount of oil supplied from the high pressure area to the back pressure chamber can be controlled by the communication ratio, there is no need for throttling due to pores, etc., and the problem of foreign object biting and blockage can be eliminated, realizing high efficiency and high reliability. A scroll compressor can be provided.

  In the scroll compressor of the present invention, excessive back pressure can be prevented and stable back pressure can be applied by intermittently communicating the high pressure region and the back pressure chamber, and the back pressure chamber and the compression chamber, respectively. In addition, since the amount of oil supplied from the high pressure area to the back pressure chamber can be controlled by the communication ratio, there is no need for throttling due to pores, etc., and the problem of foreign object biting and blockage can be eliminated, realizing high efficiency and high reliability. can do.

  According to a first aspect of the present invention, a compression scroll is formed between the fixed scroll and the orbiting scroll where the spiral wrap rises from the end plate, and a seal member is disposed on the back of the orbiting scroll, thereby providing a high pressure region and a back pressure chamber. The orbiting scroll revolves with a predetermined orbiting radius along the circular orbit by regulation by the rotation restraining mechanism, and the compression chamber moves toward the center while changing the volume, and a series of suction, compression and discharge A scroll compressor that operates, and is provided with a first path that communicates from the high pressure region to the back pressure chamber through the inside of the orbiting scroll, and the back pressure chamber side opening end of the first path travels the seal member. A second path is provided on the thrust surface of the fixed scroll, and the open end on the back pressure chamber side of the second path is the orbiting scroll. Those obtained by intermittently communicated with the back pressure chamber by the swirling Le. According to this configuration, excessive back pressure can be prevented and stable back pressure can be applied. In addition, since the amount of oil supplied from the high pressure area to the back pressure chamber can be controlled by the communication ratio, there is no need for throttling of pores, etc., and the problem of foreign object biting and blockage can be eliminated, realizing high efficiency and high reliability. A scroll compressor can be provided.

  In the second invention, in particular, the communication ratio of the second route of the first invention is equal to or greater than the communication ratio of the first route. According to this configuration, the pressure in the back pressure chamber is abnormal because the section communicating from the back pressure chamber to the compression chamber is longer than the section supplying oil from the high pressure region to the back pressure chamber in one rotation. There is no fear of rising. That is, since no excessive back pressure is applied to the orbiting scroll, it is possible to provide a scroll compressor that realizes high efficiency and high reliability.

  In the third invention, in particular, the first path communicates only when the second path of the first or second invention communicates. According to this configuration, while oil is supplied from the high pressure region to the back pressure chamber, it always communicates with the compression chamber, so the oil does not accumulate in the back pressure chamber and the back pressure rises abnormally. There is no fear. That is, since no excessive back pressure is applied to the orbiting scroll, it is possible to provide a scroll compressor that realizes high efficiency and high reliability.

  In the fourth invention, in particular, the second path according to any one of the first to third inventions is provided at a position where the back pressure chamber and the suction port do not communicate with each other. According to this configuration, since the back pressure chamber communicates only with the compression chamber, the fluctuation of the back pressure per rotation is small, and as a result, it is easy to set the predetermined back pressure. A scroll compressor that realizes performance can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 is a longitudinal sectional view of a scroll compressor according to a first embodiment of the present invention, FIG. 2 is a longitudinal sectional view of a compression mechanism portion of FIG. 1, and FIG. 3 is a transverse sectional view of the compression mechanism portion of FIG. It is.

  Hereinafter, the operation and effect of the scroll compressor according to the first embodiment of the present invention will be described.

  As shown in FIGS. 1, 2, and 3, the scroll compressor according to the present embodiment includes a main bearing member 11 of the crankshaft 4 that is fixed in the sealed container 1 by welding or shrink fitting, and the main bearing member 11. The scroll-type compression mechanism 2 is configured by sandwiching the orbiting scroll 13 meshing with the fixed scroll 12 between the fixed scroll 12 bolted on the bearing member 11, and the orbiting scroll 13 and the main bearing member 11 are orbited. By providing a rotation restraining mechanism 14 such as an Oldham ring that prevents the scroll 13 from rotating and guides it to move in a circular orbit, and the eccentric scroll portion 13 a at the upper end of the crankshaft 4 is driven eccentrically. The orbiting scroll 13 is moved in a circular orbit so that the compression chamber 15 formed between the fixed scroll 12 and the orbiting scroll 13 is centered from the outer peripheral side. The refrigerant gas is sucked and compressed from the suction pipe 16 communicating with the outside of the hermetic container 1 and the suction port 17 on the outer peripheral portion of the fixed scroll 12 by using the small size while moving to the predetermined pressure. The refrigerant gas is repeatedly discharged from the discharge port 18 at the center of the fixed scroll 12 by opening the reed valve 19 into the sealed container 1.

  On the lap upper surface 13a of the orbiting scroll 13, based on the result of measuring the temperature distribution during the operation, the honey height gradually increases from the winding start portion as the central portion to the winding end portion as the outer peripheral portion. Is provided with a slope shape. Thereby, the dimensional change by thermal expansion can be absorbed and local sliding can be prevented.

  Further, by disposing the seal member 78 on the back surface 13b of the orbiting scroll 13, a high pressure region 30 and a back pressure chamber 29 set to an intermediate pressure between high pressure and low pressure are formed. By applying pressure on the back surface 13b, the orbiting scroll 13 is stably pressed against the fixed scroll 12, reducing leakage and performing stable circular orbit movement.

  During operation of the compressor, a pump 25 is provided at the lower end of the crankshaft 4 and is driven simultaneously with the scroll compressor. As a result, the pump 25 sucks up the oil 6 in the oil reservoir 20 provided at the bottom of the hermetic container 1 and supplies it to the compression mechanism 2 through the oil supply hole 26 extending vertically through the crankshaft 4. The supply pressure at this time is substantially equal to the discharge pressure of the scroll compressor, and also serves as a back pressure source for the orbiting scroll 13. As a result, the orbiting scroll 13 does not move away from the fixed scroll 12 and does not come into contact with one another, and the predetermined compression function is stably exhibited.

  A part of the oil 6 supplied in this way is obtained by a supply pressure or its own weight so as to obtain a clearance, between the fitting portion between the eccentric shaft portion 4a and the orbiting scroll 13, and between the crankshaft 4 and the main bearing member 11. Then, the oil enters the bearing portion 66, lubricates the respective portions, falls, and returns to the oil sump 20. Another part of the oil 6 supplied to the high-pressure region 30 passes through the first path 54 that opens to the high-pressure region 30, is around the outer periphery of the orbiting scroll 13, and the rotation restraint mechanism 14 is located. Along with entering the back pressure chamber 29 and lubricating the thrust sliding portion and the sliding portion of the rotation restraint mechanism 14, the back pressure of the orbiting scroll 13 is applied in the back pressure chamber 29.

  Further, the compression chamber 15 is intermittently communicated from the back pressure chamber 29 by moving the seal member 78 back and forth at the back pressure chamber side opening end 54 a of the first path 54. A second path 55 that opens to the back pressure chamber 29 is formed on the thrust surface 12 a of the fixed scroll 12, and the back pressure chamber 29 and the compression chamber 15 are intermittently connected with the turning motion of the turning scroll 13. Communicate with. 3A is a detailed view when the back pressure chamber side opening end 55a of the second path 55 communicates with the back pressure chamber 29, and FIG. 3B is a back pressure of the second path 55. FIG. 6 is a detailed view when the chamber side opening end 55a is not in communication with the back pressure chamber 29. As a result, the oil 6 that has entered the back pressure chamber 29 through the first path 54 is guided to the compression chamber 15 through the back pressure chamber side opening end 55a of the second path 55, and is sealed during compression. Plays a role in improving lubricity and lubricity.

  Here, the amount of oil in the back pressure chamber 29 will be described. Regarding the oil 6 entering the back pressure chamber 29 from the high pressure region 30 via the first path 54 and the oil 6 entering the compression chamber 15 from the back pressure chamber 29 via the second path 55, the former When the amount of oil is large, the excess pressure of the oil 6 is supplied to the back pressure chamber 29, so that the pressure increases. As a result, excessive back pressure is applied to the orbiting scroll 13. When an excessive back pressure is applied, the thrust load increases, which causes a problem of causing performance deterioration and reliability deterioration.

  Therefore, in the scroll compressor of the present embodiment, the first path 54 and the second path 55 are intermittently communicated. Thereby, since excessive oil 6 is not supplied to the back pressure chamber 29, an abnormal increase in pressure can be prevented. As a result, excessive back pressure to the orbiting scroll 13 can be prevented, and stable back pressure can be applied. In addition, since the amount of oil supplied from the high pressure region 30 to the back pressure chamber 29 can be controlled by the communication ratio, there is no need for throttling of pores and the like, and the problem of foreign matter biting and blockage can be eliminated, and high efficiency and high reliability are achieved. The scroll compressor which implement | achieves can be provided.

  Further, the communication ratio of the second path 55 is set to be equal to or greater than the communication ratio of the first path 54. As a result, the section communicating with the compression chamber 15 from the back pressure chamber 29 is longer than the section supplying the oil 6 from the high pressure region 30 to the back pressure chamber 29 in one rotation. There is no risk of abnormal pressure rise. That is, since no excessive back pressure is applied to the orbiting scroll 13, a scroll compressor that realizes high efficiency and high reliability can be provided.

  Further, the first path 54 is communicated only when the second path 55 is in communication. As a result, while the oil 6 is being supplied from the high pressure region 30 to the back pressure chamber 29, the oil 6 is always in communication with the compression chamber 15, so that the oil 6 does not collect in the back pressure chamber 29, and the back pressure is reduced. There is no fear of an abnormal rise. That is, since no excessive back pressure is applied to the orbiting scroll 13, a scroll compressor that realizes high efficiency and high reliability can be provided.

  The second path 55 is provided at a position where the back pressure chamber 29 and the suction port 17 do not communicate with each other. According to this configuration, since the back pressure chamber 29 communicates only with the compression chamber 15, the fluctuation of the back pressure per rotation is small, and as a result, it is easy to set the predetermined back pressure. A scroll compressor that achieves high reliability can be provided.

  As described above, the scroll compressor according to the present invention allows the application of stable back pressure by allowing oil to intermittently enter the back pressure chamber from the high pressure region and from the back pressure chamber to the compression chamber. The working fluid is not limited to a refrigerant, and can be applied to applications of scroll fluid machines such as an air scroll compressor, a vacuum pump, and a scroll type expander.

The longitudinal cross-sectional view of the scroll compressor in Embodiment 1 of this invention The longitudinal cross-sectional view of the compression mechanism part of the scroll compressor in Embodiment 1 of this invention Cross-sectional view of the compression mechanism portion of the scroll compressor according to Embodiment 1 of the present invention (a) Cross-sectional view showing details when the second path communicates with the back pressure chamber (b) Second path Is a cross-sectional view showing the details when the back pressure chamber is not in communication A longitudinal sectional view of a compression mechanism of a conventional scroll compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Compression mechanism 4 Crankshaft 4a Eccentric shaft part 6 Oil 11 Main bearing member 12 Fixed scroll 12a Thrust surface 13 Orbiting scroll 13a Wrap top surface 13b Back surface 14 Rotation restraint mechanism 15 Compression chamber 16 Suction pipe 17 Suction port 18 Discharge port 19 Reed valve 20 Oil reservoir 25 Pump 26 Oil supply hole 29 Back pressure chamber 30 High pressure region 54 First path 54a Back pressure chamber side open end 55 Second path 55a Back pressure chamber side open end 66 Bearing portion 78 Seal member

Claims (4)

A compression scroll is formed between the fixed scroll and the orbiting scroll where the spiral wrap rises from the end plate, and a high pressure region and a back pressure chamber are formed by arranging a seal member on the back of the orbiting scroll, and the rotation The orbiting scroll orbits with a predetermined orbiting radius along a circular orbit by restriction by a restraining mechanism, so that the compression chamber moves toward the center while changing the volume, and performs a series of operations of suction, compression and discharge. The scroll compressor is provided with a first path communicating from the high pressure region to the back pressure chamber through the inside of the orbiting scroll, and the back pressure chamber side opening end of the first path is the seal member. A second path on the thrust surface of the fixed scroll, wherein the second path is connected to only one of the back pressure chamber and the compression chamber. Scroll compressor the back pressure chamber side opening end of the second path is characterized by causing intermittently through the back pressure chamber and communicating by the turning of the orbiting scroll. The scroll compressor according to claim 1, wherein the communication ratio of the second path is equal to or greater than the communication ratio of the first path. The scroll compressor according to claim 1 or 2, wherein the first path is connected only when the second path is in communication. The scroll compressor according to any one of claims 1 to 3, wherein the second path is provided at a position where the back pressure chamber and the suction port do not communicate with each other.