JP2013231356A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor with improved reliability and stability by avoiding an operation under high-load conditions.SOLUTION: A rotary compressor 1 comprises an electric element 4 and a rotary compression element 7 in a sealed vessel 3. The rotary compressor further includes a high-pressure control circuit 31 comprising: a bypass path 32 for making a high-pressure side communicate with a low-pressure side; and a high-pressure control valve 33 provided at the bypass path 32. The high-pressure control valve 33 is opened when pressure on the high-pressure side rises to a set value. While the high-pressure control valve 33 is opened, the high-pressure control circuit 31 adjusts the amount of a refrigerant circulating in the high-pressure side and returns the refrigerant to the low-pressure side.

Description

  The present invention relates to a compressor provided with an electric element and a compression element in an airtight container.

  Conventionally, this type of compressor, particularly a rotary compressor, houses an electric element and a rotary compression element in a hermetic container, and rotationally drives the rotary compression element on the rotating shaft of the electric element, and also has a refrigerant suction pipe attached to the hermetic container. The refrigerant is sucked into the rotary compression element, compressed by the action of the roller and vane rotating eccentrically in the cylinder, discharged into the sealed container, and discharged to the external refrigerant circuit from the refrigerant discharge pipe attached to the sealed container It was set as the structure to perform (for example, refer patent document 1).

JP 2004-245152 A

  When such a compressor is used, for example, in an air conditioner installed in a high-temperature area (such as countries in the Middle East), the temperature of the condenser constituting the refrigerant circuit increases to, for example, + 65 ° C. or higher. Easy to fall into load conditions. In that case, the pressure on the high-pressure side of the refrigerant circuit also rises abnormally, so that the compressor is stopped and protected by the operation of the high-pressure switch and relay provided on the high-pressure side of the refrigerant circuit, but cannot be started for at least several minutes. Therefore, the user's comfort is impaired.

  In order to avoid such a situation, there is also a method of releasing the high-pressure refrigerant gas in the sealed container to the outside as in Patent Document 1 when the pressure on the high-pressure side rises to a predetermined value due to a high load condition. Although it is conceivable, since the refrigerant will be discharged to the outside, an environmental pollution problem will occur.

  The present invention has been made to solve the conventional technical problems, and an object of the present invention is to provide a compressor with improved reliability and stability by avoiding operation under high load conditions. To do.

  The compressor of the present invention comprises an electric element and a compression element in a hermetically sealed container, and comprises a bypass passage communicating the high pressure side and the low pressure side, and a high pressure control valve provided in the bypass passage. A high pressure control circuit is provided, and the high pressure control valve opens when the pressure on the high pressure side rises to a set value.

  The compressor of the invention of claim 2 is characterized in that, in the above, the high pressure control circuit adjusts the refrigerant circulation amount on the high pressure side to return to the low pressure side with the high pressure control valve opened.

  According to a third aspect of the present invention, there is provided a compressor according to a third aspect of the present invention, wherein the compression element is a cylinder, a roller that rotates eccentrically in the cylinder by an eccentric portion provided on the rotating shaft of the electric element, and an abutting contact with the roller. A vane that is divided into a low-pressure chamber side and a high-pressure chamber side, and a support member that closes the opening surface of the cylinder and also serves as a bearing for the rotary shaft, and the refrigerant compressed on the high-pressure chamber side in the cylinder are placed in a sealed container The refrigerant is discharged from the refrigerant discharge pipe attached to the sealed container, and the high-pressure control circuit is characterized in that the inside of the sealed container and the low-pressure chamber side of the cylinder communicate with each other.

  The compressor of the invention of claim 4 is characterized in that a part of the bypass passage of the high-pressure control circuit is provided in the support member.

  A compressor according to a fifth aspect of the present invention includes the refrigerant suction pipe attached to the airtight container according to the first or second aspect, and an accumulator provided in the refrigerant suction pipe, and the compression element draws the refrigerant from the refrigerant suction pipe. While being sucked in and compressed, the bypass passage of the high-pressure control circuit communicates the high-pressure side with the accumulator.

  According to a sixth aspect of the present invention, there is provided a compressor according to the first or second aspect, comprising the refrigerant suction pipe attached to the closed container and an accumulator provided on the refrigerant suction pipe, and the compression element seals the compressed refrigerant. It discharges in a container and discharges from the refrigerant | coolant discharge pipe provided in this airtight container, and a high voltage | pressure control circuit connects the inside of an airtight container and an accumulator.

  The compressor of the invention of claim 7 is characterized in that the high-pressure control circuit is held in the sealed container by the bracket attached to the outer surface of the sealed container in each of the above inventions.

  According to the present invention, in a compressor including an electric element and a compression element in a hermetically sealed container, a high pressure control comprising a bypass passage communicating the high pressure side and the low pressure side and a high pressure control valve provided in the bypass passage. Since the high pressure control valve is equipped with a circuit and opens when the pressure on the high pressure side rises to the set value, the set value at which this high pressure control valve opens can be set to a value lower than the abnormal high pressure under high load conditions. Before falling into a high load condition, the pressure on the high pressure side can be released to the low pressure side.

  In other words, operation under high load conditions can be avoided without stopping the compressor, ensuring continuous operation of the compressor, improving compressor reliability, and ensuring comfort for the user. It becomes possible to do. In addition, since it is possible to delete the high-pressure switch attached to the refrigerant circuit side for protecting the compressor, the design of the refrigerant circuit is simplified. Furthermore, since operation under high load conditions is avoided, load torque required for the electric element can be reduced, and performance can be improved. And since it is not what escapes a refrigerant | coolant outside conventionally, it becomes possible to avoid an environmental pollution problem.

  In this case, if the high-pressure side refrigerant circulation amount is adjusted and returned to the low-pressure side with the high-pressure control valve of the high-pressure control circuit opened as in the second aspect of the invention, the pressure increase on the high-pressure side is suppressed. It will be able to.

  According to a third aspect of the present invention, the compression element includes a cylinder, a roller that rotates eccentrically in the cylinder by an eccentric portion provided on the rotating shaft of the electric element, and a low pressure chamber side in contact with the roller. A vane sectioned on the high-pressure chamber side, and a support member that closes the opening surface of the cylinder and also serves as a bearing for the rotary shaft, and discharges the refrigerant compressed on the high-pressure chamber side in the cylinder into the sealed container. In the case of a rotary type compressor that discharges from a refrigerant discharge pipe attached to a hermetic container, if the high pressure control circuit allows the inside of the hermetic container to communicate with the low pressure chamber side of the cylinder, the refrigerant on the high pressure side under high load conditions Can be directly returned to the low-pressure chamber side of the cylinder and compressed together with the low-pressure refrigerant sucked into the low-pressure chamber side.

  In this case, if a part of the bypass passage of the high voltage control circuit is provided in the support member as in the invention of claim 4, it is not necessary to configure a part of the bypass passage in the cylinder that requires precision. The workability is improved.

  On the other hand, when the compression element includes a refrigerant suction pipe attached to the closed container as in the invention of claim 5 and an accumulator provided in the refrigerant suction pipe and the compression element sucks and compresses the refrigerant from the refrigerant suction pipe, the high pressure control is performed. If the high-pressure side and the accumulator are communicated with each other by the circuit bypass passage, a high-pressure control circuit can be constructed outside the sealed container, and productivity is also improved by returning to the accumulator instead of piping. It will improve.

  At this time, as in the invention of claim 6, the compression element discharges the compressed refrigerant into the sealed container and discharges it from the refrigerant discharge pipe provided in the sealed container. If the communication is made, the productivity is further improved.

  Furthermore, if the bracket is attached to the outer surface of the sealed container as in the invention of claim 7 and the high pressure control circuit is held in the sealed container by this bracket, the entire compressor including the high pressure control circuit can be made compact. It will be.

It is a side view of the rotary compressor as an Example of the compressor to which this invention is applied. It is a vertical side view of the rotary compressor of FIG. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a top view of the cylinder part of the rotary compressor of FIG. It is a figure explaining operation | movement of the rotary compression element as an Example of the compression element of the rotary compressor of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a side view of a rotary compressor 1 as an embodiment of a compressor to which the present invention is applied, FIG. 2 is a longitudinal side view thereof, FIG. 3 is an enlarged view of a main part of FIG. 2, and FIG. FIG.

  In each of the drawings, a rotary compressor 1 according to an embodiment includes a cylindrical sealed container 3, an electric element (drive element) 4 including a motor housed and disposed above the inner space of the sealed container 3, and the electric element 4. It is housed and arranged in the internal space of the lower closed container 3 and is composed of a rotary compression element 7 as a compression element that is rotationally driven by the rotary shaft 6 of the electric element 4.

  The end cap 3A at the upper end of the sealed container 3 has a terminal 8 for supplying electric power to the electric element 4, and high-pressure refrigerant gas discharged into the sealed container 3 as described later to a condenser or gas cooler of an external refrigerant circuit. A refrigerant discharge pipe 9 for discharging is attached.

  The electric element 4 includes an annular stator 11 attached along the inner surface of the hermetic container 3 and a rotor 12 inserted and installed with a slight gap inside the stator 11. The rotor 12 is centered. It is attached to the rotating shaft 6 extending in the vertical direction.

  The rotary compression element 7 is housed in the cylinder 2, a roller 16 that is eccentrically rotated by an eccentric portion (crank) 14 provided in the rotary shaft 6, and a vane slot 17 </ b> A of the cylinder 2 so as to be able to appear and retract. In contact with the roller 16, the internal space of the cylinder 2 (compression chamber between the cylinder 2 and the roller 16) is moved to the low pressure chamber side (compression chamber in the suction process) 13A and the high pressure chamber side (compression chamber in the compression process) 13B. The vane 17 is divided into an upper support member 18 and a lower support member 19 that serve as bearing members for the rotary shaft 6 by closing the upper surface opening and the lower surface opening of the cylinder 2.

  The cylinder 2 is formed with a suction port 21 communicating with the internal low pressure chamber 13A side. The upper support member 18 and the lower support member 19 include upper and lower discharge ports 22 communicating with the high pressure chamber 13B side within the cylinder 2, 23, and mufflers 24 and 26 communicating with the respective discharge ports 22 and 23 are formed on the upper side of the upper support member 18 and the lower side of the lower support member 19. The mufflers 24 and 46 communicate with the inside of the sealed container 3 through discharge holes (not shown).

  A refrigerant suction pipe 27 is further attached to the sealed container 3, and one end of the refrigerant suction pipe 27 is connected to the suction port 21 of the cylinder 2 via a sleeve 28. The refrigerant suction pipe 27 is provided with an accumulator 29, and the other end of the refrigerant suction pipe 27 enters the accumulator 29 from below and opens at the top. The accumulator 29 is held in the sealed container 3 by a bracket 31 attached to the outer surface of the sealed container 3.

  For example, the refrigerant discharge pipe 9 is connected to an inlet of a condenser (not shown) or a gas cooler constituting a refrigerant circuit of an air conditioner, and an inlet of the accumulator 29 is connected to an outlet of an evaporator (not shown) constituting a refrigerant circuit. The refrigerant circuit is configured by annularly connecting the rotary compressor 1, a condenser (gas cooler), an unillustrated expansion valve (decompression device), and an evaporator. For example, R410A is enclosed as a refrigerant.

  A high pressure control circuit 31 is attached to the rotary compressor 1 of the present invention. The high-pressure control circuit 31 of the embodiment includes a bypass passage 32 constituted by piping and a high-pressure control valve 33 interposed in the middle of the bypass passage 32. One end of the bypass passage 32 is inserted into an attachment hole 34 formed in the sealed container 3 and fixed to the sealed container 3, and communicates with the sealed container 3 below the stator 11. The other end of the bypass passage 32 is also inserted into a mounting hole 36 formed in the sealed container 3. A sleeve 37 is connected to the other end of the bypass passage 32, and a connecting pipe 38 having a pore 38 </ b> A is attached to the sleeve 37.

  On the other hand, the lower support member 19 is provided with a return hole 41 having one end opened at a position corresponding to the mounting hole 34, and the other end of the return hole 41 is formed corresponding to the inner space of the cylinder 2. The cylinder 41 communicates with the opening 41A. The connecting pipe 38 is inserted and connected to one end opening of the return hole 41 of the lower support member 19. Thereby, the sleeve 37, the connecting pipe 38, and the return hole 41 constitute a part of the bypass passage 32.

  The opening 41 </ b> A of the return hole 41 is formed corresponding to the lower side of the low pressure chamber 13 </ b> A in the cylinder 2. Thereby, the bypass passage 32 communicates the inside of the sealed container 3 (high pressure side) with the low pressure chamber side 13A (low pressure side) of the cylinder 2.

  The high-pressure control valve 33 is always closed by the acting force of a spring (not shown), and the high-pressure side pressure at which the rotary compressor 1 is in a high load condition (for example, a high pressure switch of a refrigerant circuit (not shown in the high load condition) This is a valve that opens the flow path of the bypass passage 32 at a predetermined set value (for example, 4 MPa) lower than 5 MPa that operates. The high-pressure control valve 33 and the bypass passage 32 constituting the high-pressure control circuit 31 are attached to the sealed container 3 by a bracket 43 attached to the outer surface of the sealed container 3.

  With the above configuration, when the electric element 4 is energized from the terminal 8 of the rotary compressor 1 and the rotor 12 rotates in the stator 11 and the rotating shaft 6 rotates, the roller 16 is moved by the eccentric portion 14 of the rotating shaft 6 as shown in FIG. It rotates counterclockwise in FIG. In FIG. 5, the upper left is a state where the roller 16 has pushed the vane 17 most into the vane slot 17A at a crank angle of 0 °, the upper right is a state rotated by 90 °, the lower left is a state rotated by 180 °, and the lower right is rotated by 270 °. Each state is shown.

  Since the volume of the low-pressure chamber side 13A communicating with the suction port 21 increases in the process of rotating from a crank angle of 0 ° to 90 °, 180 °, and 270 °, the suction port 21 is connected via the accumulator 29 and the refrigerant suction pipe 27. The refrigerant on the low pressure side is sucked into the low pressure chamber side 13 </ b> A in the cylinder 2. On the other hand, since the volume of the high-pressure chamber side 13B communicating with the discharge ports 22 and 23 is reduced, the internal refrigerant is compressed, and a discharge valve (not shown) that closes the discharge ports 22 and 23 at a predetermined pressure. ) Is opened, and the compressed and high pressure refrigerant is discharged to the mufflers 24 and 26. The high-pressure refrigerant gas discharged to the mufflers 24 and 26 is discharged from the discharge hole into the sealed container 3, and passes through the gap between the stator 11 and the rotor 12 of the electric element 4 or between the stator 11 and the sealed container 3. And is discharged from the refrigerant discharge pipe 9 to the outside.

  The refrigerant discharged to the refrigerant discharge pipe 9 dissipates heat by the condenser (gas cooler), is decompressed by the expansion valve, evaporates by the evaporator, and reaches the accumulator 29. Then, the cycle of suction from the accumulator 29 through the refrigerant suction pipe 27 into the cylinder 2 is repeated. By this operation, the high pressure side of the refrigerant circuit from the high pressure chamber side 13B of the cylinder 2 through the inside of the sealed container 3 to the expansion valve becomes about 3 MPa in a normal operation state, and from the expansion valve through the evaporator and accumulator 29, The low pressure side of the refrigerant circuit reaching the low pressure chamber 13A is about 0.5 to 1 MPa.

  In the embodiment, the opening 41A constituting the bypass passage 32 of the high pressure control circuit 31 is formed at a position communicating with the low pressure chamber side 13A in the cylinder 2 at a crank angle of 270 ° (FIGS. 4 and 5). Accordingly, the opening 41 </ b> A is closed by the lower surface of the roller 16 at a rotation angle of the roller 16 other than the crank angle near 270 °.

  Here, under a high load condition in which the temperature of the use environment is high and the condensation temperature in the condenser is, for example, + 65 ° C. or higher, the pressure on the high pressure side of the refrigerant circuit is extremely high, and the rotary compressor 1 is in a very high load state. It falls into the state where it is driven by. In such a case, the rotary compressor 1 is stopped and protected by the operation of a relay (temperature, current) provided on the high pressure side of the refrigerant circuit. Further, when the high pressure switch attached to the high pressure side of the refrigerant circuit detects the 5 MPa on the high pressure side, the rotary compressor 1 is cut off and stopped. Before the pressure rises, the high pressure control valve 33 opens the bypass passage 32 when the pressure in the sealed container 3 (high pressure side) rises to 4 MPa.

  When the bypass passage 32 is opened, the refrigerant gas in the hermetic container 3 is throttled by the pores 38A through the bypass passage 32, and then the low pressure chamber side 13A of the cylinder 2 from the opening 41A (in the state where the crank angle is 270 °). In). As a result, the pressure on the high pressure side of the refrigerant circuit including the inside of the hermetic container 3 escapes to the low pressure side, so that the pressure on the high pressure side is reduced and returned to the normal operation state, and the above-described stop by the high pressure switch is also avoided. Is done.

  The refrigerant quantity returned at this time is set to 50% or less of the circulation quantity. If this return amount is too large, the pressure on the low pressure side will rise and the capacity of the rotary compressor 1 itself will fall too much. If the amount is too small, the effect of lowering the high pressure is reduced, so an appropriate amount is set according to the output of the rotary compressor 1 and the like. The setting of the return amount is determined by the amount of restriction by the hole diameter of the fine hole 38A and the inner passage diameter (passage area) when the high pressure control valve 33 is opened. That is, the passage in the passage of the high-pressure control valve 33 is small even when the flow path is opened, and the refrigerant is throttled at that portion. Therefore, depending on the design of the high-pressure control valve 33, it may not be the pore 38A.

  As described above, the high-pressure control circuit 31 including the bypass passage 32 that communicates the high-pressure side and the low-pressure side with the rotary compressor 1 and the high-pressure control valve 33 provided in the bypass passage 32 is provided. Since the high pressure side valve is opened when the pressure on the high pressure side rises to the set value, the set value at which the high pressure control valve 33 opens is lower than the abnormal high pressure (5 MPa in the embodiment) under the high load condition (4 MPa in the embodiment). ), The pressure on the high pressure side can be released to the low pressure side before falling into a high load condition.

  That is, the rotary compressor 1 can be avoided from being stopped by the high-pressure switch and the operation under high load conditions can be avoided, so that the stable operation of the rotary compressor 1 can be ensured and the reliability of the rotary compressor 1 can be improved. It is possible to improve the air-conditioner driving comfort for the user. In addition, since it becomes possible to delete the high pressure switch attached to the refrigerant circuit side for the purpose of protecting the rotary compressor 1, the design of the refrigerant circuit is simplified.

  Further, since operation under high load conditions is avoided, load torque required for the electric element 4 can be reduced, and it is possible to improve operation efficiency and performance. And since it is not what escapes a refrigerant | coolant outside conventionally, it becomes possible to avoid an environmental pollution problem.

  In this case, since the high-pressure side refrigerant is squeezed back to the low-pressure side while the high-pressure control valve 33 of the high-pressure control circuit 31 is open, an increase in the pressure on the low-pressure side can be suppressed. Further, since the high pressure control circuit 31 allows the inside of the sealed container 3 to communicate with the low pressure chamber side 13A of the cylinder 2, the high pressure side refrigerant is directly returned to the low pressure chamber side 13A of the cylinder 2 under high load conditions. It becomes possible to compress the refrigerant together with the low-pressure refrigerant sucked into the low-pressure chamber side 13A.

  In particular, since the connecting pipe 38 and the sleeve 37 that constitute a part of the bypass passage 32 of the high-pressure control circuit 31 are provided in the lower support member 19, a part of the bypass passage is constructed in the cylinder 2 that requires high precision. This eliminates the need for improved workability.

  Furthermore, since the bracket 43 is attached to the outer surface of the hermetic container 3 and the high-pressure control circuit 31 is held in the hermetic container 3 by the bracket 43, the entire rotary compressor 1 including the high-pressure control circuit 31 is made compact. Is possible.

  Here, in the first embodiment, the bypass passage 32 of the high-pressure control circuit 31 is finally connected to the cylinder 2. However, the present invention is not limited to this, and as shown by the broken line in FIG. You may make it connect the channel | path 32 (the part is shown by 32A) to the accumulator 29 (low pressure side of a refrigerant circuit).

  According to such a configuration, the high-pressure control circuit 31 can be configured outside the sealed container 3, and the connection is simplified and the productivity is improved by returning to the accumulator 29 instead of the piping. In particular, the high-pressure control circuit 31 only needs to connect the closed container 3 and the accumulator 29, so that the productivity is further improved.

  In the above embodiments, the rotary compressor has been described as an example. However, the present invention is not limited to this, and the present invention may be applied to a scroll compressor or the like. In each of the above embodiments, the high-pressure refrigerant in the hermetic container 3 is returned to the low-pressure chamber side 13A of the cylinder 2 and the accumulator 29. However, the present invention is not limited to this. The present invention is effective if the low voltage side can be communicated with the high voltage control circuit 31.

DESCRIPTION OF SYMBOLS 1 Rotary compressor 2 Cylinder 3 Sealed container 4 Electric element 6 Rotating shaft 7 Rotation compression element 9 Refrigerant discharge pipe 13A Low pressure chamber side 13B High pressure chamber side 14 Eccentric part 16 Roller 17 Vane 18 Upper support member 19 Lower support member 21 Suction port 22, 23 Discharge port 24, 26 Muffler 27 Refrigerant suction pipe 29 Accumulator 31 High pressure control circuit 32 Bypass passage 33 High pressure control valve 38 Connection pipe 38A Pore

Claims (7)

In a compressor comprising an electric element and a compression element in a sealed container,
A high-pressure control circuit comprising a bypass passage communicating the high-pressure side and the low-pressure side, and a high-pressure control valve provided in the bypass passage, wherein the high-pressure control valve is configured such that the pressure on the high-pressure side rises to a set value Compressor characterized by opening in.   2. The compressor according to claim 1, wherein the high-pressure control circuit adjusts a refrigerant circulation amount on the high-pressure side to return to the low-pressure side in a state where the high-pressure control valve is open. The compression element includes a cylinder, a roller that rotates eccentrically in the cylinder by an eccentric portion provided on a rotating shaft of the electric element, and the cylinder is divided into a low pressure chamber side and a high pressure chamber side in contact with the roller And a support member that closes the opening surface of the cylinder and also serves as a bearing for the rotating shaft,
The refrigerant compressed on the high-pressure chamber side in the cylinder is discharged into the sealed container, and is discharged from a refrigerant discharge pipe attached to the sealed container.
3. The compressor according to claim 1, wherein the high-pressure control circuit communicates the inside of the sealed container with a low-pressure chamber side of the cylinder.   The compressor according to claim 3, wherein a part of a bypass passage of the high-pressure control circuit is provided in the support member. A refrigerant suction pipe attached to the closed container, and an accumulator provided in the refrigerant suction pipe,
3. The compression element according to claim 1, wherein the compression element sucks and compresses the refrigerant from the refrigerant suction pipe, and a bypass passage of the high-pressure control circuit communicates the high-pressure side with the accumulator. Compressor. A refrigerant suction pipe attached to the closed container, and an accumulator provided in the refrigerant suction pipe,
The compression element discharges the compressed refrigerant into the closed container, discharges it from a refrigerant discharge pipe provided in the closed container,
3. The compressor according to claim 1, wherein the high-pressure control circuit communicates the inside of the sealed container with the accumulator.   The compressor according to any one of claims 1 to 6, wherein the high-pressure control circuit is held in the sealed container by a bracket attached to the outer surface of the sealed container.

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