JP6071190B2 - Multi-cylinder rotary compressor and refrigeration cycle apparatus - Google Patents

Description

  Embodiments described herein relate generally to a multi-cylinder rotary compressor and a refrigeration cycle apparatus using the multi-cylinder rotary compressor.

  In the refrigeration cycle apparatus, a compression mechanism portion having a plurality of (mainly two) cylinders and an electric motor portion that drives the compression mechanism portion are housed in a hermetically sealed case, and the high-pressure compressed in the cylinder chamber of each cylinder A multi-cylinder rotary compressor that discharges a gas refrigerant into a sealed case is often used. If this type of multi-cylinder rotary compressor can be switched between full capacity operation that compresses gas refrigerant in all cylinder chambers and reduced capacity operation that stops compression of gas refrigerant in some cylinder chambers, This is advantageous in terms of efficiency and power consumption.

  As a multi-cylinder rotary compressor having two cylinders and capable of switching between full capacity operation and capacity reduction operation as required, one described in Patent Document 1 below is known.

  The compression mechanism of the multi-cylinder rotary compressor described in Patent Document 1 is provided with two cylinders each having a cylinder chamber. Each cylinder has a roller that rotates eccentrically within the cylinder chamber, and a roller that contacts and separates from the roller. And a blade that divides the cylinder chamber into two spaces when the tip contacts the outer peripheral surface of the roller, and communicates with the cylinder chamber and is located on the rear end side of the blade. A blade back chamber for supplying pressure for sliding the blade in the direction of contacting and separating from the roller;

  The low-pressure or high-pressure gas refrigerant switched in the pressure switching unit equipped with the electromagnetic valve flows selectively through the back pressure passage into the blade back chamber of one cylinder. When a high-pressure gas refrigerant is introduced into the blade back chamber, the blade is urged by the pressure and the tip of the blade comes into contact with the outer peripheral surface of the roller, and the cylinder enters a compression operation state. In this cylinder in the compression operation state, the low-pressure gas refrigerant that has passed through the accumulator flows through the suction pipe and is sucked into the cylinder chamber. On the other hand, when a low-pressure gas refrigerant is introduced into the blade back chamber by switching the electromagnetic valve, the blade is not biased toward the roller side, and the tip of the blade moves away from the outer peripheral surface of the roller. It will be in the non-compression operation state (cylinderless state) where compression is stopped. When the cylinder is in a cylinder resting state, the low-pressure gas refrigerant is not sucked from the accumulator into the cylinder chamber.

  A spring member is housed in the blade back chamber of the other cylinder, and the blade is always in contact with the outer peripheral surface of the roller by the biasing force of the spring member. Thus, when the multi-cylinder rotary compressor is in operation, the cylinder is always in a compression operation state, and the low-pressure gas refrigerant that has passed through the accumulator flows through the suction pipe and is sucked into the cylinder chamber.

  The low-pressure gas refrigerant introduced into the blade back chamber is guided to the pressure switching unit from the refrigerant pipe upstream of the accumulator along the flow direction of the gas refrigerant in the refrigeration cycle apparatus and is switched by the pressure switching unit. It flows in the pressure passage and is guided into the blade back chamber.

By the way, since the high pressure gas refrigerant compressed in the cylinder chamber is discharged and becomes high pressure in the sealed case, the pressure is higher than the pressure in the cylinder chamber of the cylinder in the cylinder resting state. For this reason, in a cylinder with a cylinder closed, lubricating oil stored in the sealed case enters the cylinder chamber due to a pressure difference between the sealed case and the cylinder chamber. The lubricating oil that has entered the cylinder chamber flows into the blade back chamber through the gap between the blade and the blade groove, and further reaches the pressure switching section via the back pressure passage. Further, the refrigerant flows into the accumulator from the refrigerant pipe connected to the pressure switching unit.

  The lubricating oil flowing into the accumulator flows into the suction pipe through a small hole formed in the portion of the suction pipe located in the accumulator, flows through the suction pipe together with the low-pressure gas refrigerant, and is sucked into the cylinder chamber. Are discharged into the sealed case together with the gas refrigerant compressed to a high pressure. That is, the lubricating oil that has entered the cylinder chamber of the cylinder that has been in a closed cylinder state from the inside of the sealed case during the capacity reduction operation is returned to the sealed case after flowing into the accumulator.

JP 2006-22766 A

  However, due to the viscosity of the lubricating oil, when the flow rate of the gas refrigerant flowing through the suction pipe is low, the return of the lubricating oil from the accumulator into the sealed case is reduced, and the lubricating oil in the sealed case is insufficient.

  When the lubricating oil in the sealed case is insufficient, the sliding portion of the compression mechanism portion in the sealed case becomes insufficiently lubricated, causing a disadvantage that the sliding portion is worn.

  The purpose of the embodiment of the present invention is that when the lubricating oil stored in the sealed case flows out of the sealed case via the blade back chamber of the cylinder that is in an uncompressed operation state (cylinderless state), A multi-cylinder rotary compressor and a multi-cylinder rotary compressor capable of preventing the lubricating oil in the sealed case from being deficient by allowing the lubricating oil to return to the sealed case without flowing into the accumulator. It is to provide a used refrigeration cycle apparatus.

The multi-cylinder rotary compressor of the embodiment has a first cylinder that has a first cylinder chamber and can be switched between a compression operation state and a non-compression operation state of a closed cylinder, and a second cylinder chamber. A compression mechanism that compresses a low-pressure working fluid supplied from an accumulator via a suction pipe, an electric motor that drives the compression mechanism, and a compression mechanism thereof. The first cylinder has a first roller that rotates eccentrically within the first cylinder chamber, and a tip that is slidable in a direction contacting and separating from the first roller. A first blade that divides the first cylinder chamber into two spaces when it comes into contact with the outer peripheral surface of the first roller and a rear end side of the first blade, and the first blade is in contact with the first roller. To slide away And a first blade back chamber for supplying pressure, and discharges the high-pressure working fluid compressed by the first and second cylinder chamber in the sealed case. Two suction pipes are provided, one suction pipe for supplying a low-pressure working fluid to the first cylinder chamber and the other suction pipe for supplying a low-pressure working fluid to the second cylinder chamber. Furthermore, a back pressure introduction pipe whose one end communicates with the first blade back chamber, and the other end of the back pressure introduction pipe communicates with the first blade back chamber via the back pressure introduction pipe. a pressure switching unit for guiding by switching the fluid, one end of which communicates with the pressure switching unit, a low pressure of the working fluid and the other end from the accumulator with communicates with the back-pressure pipe when the first cylinder is in a non-compression operation state A working fluid introduction pipe communicated with the other suction pipe supplied to the second cylinder chamber, and the working fluid introduction pipe and the back pressure introduction pipe are formed to have a smaller diameter than the other suction pipe. Further, the high pressure working fluid discharged from the discharge pipe is disposed between the discharge pipe and the pressure switching section provided at the upper part of the sealed case and discharging the high pressure working fluid in the sealed case to the outside of the sealed case. Is connected to a high-pressure gas refrigerant introduction pipe. The compression mechanism section further includes a communication path that communicates between the first blade back chamber and the inside of the sealed case, and a check valve mechanism that opens and closes the communication path. When the first blade slides in a direction to increase the volume of the first blade back chamber, the communication path is closed, and the first blade slides in a direction to reduce the volume of the first blade back chamber. The communication path is opened.

It is a lineblock diagram of the refrigerating cycle device containing the multicylinder rotary compressor of a 1st embodiment shown in the section. It is a disassembled perspective view which expands and shows a part of compression mechanism part. It is a figure which expands and shows the attachment structure of the non-return valve mechanism to a closure member. FIG. 4 is a sectional view taken along line XX in FIG. 3. It is a block diagram of the refrigerating-cycle apparatus containing the multicylinder rotary compressor of 2nd Embodiment shown in the cross section.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
A first embodiment will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of a multi-cylinder rotary compressor A and a configuration diagram of a refrigeration cycle apparatus S including the multi-cylinder rotary compressor A.

  First, the multi-cylinder rotary compressor A will be described. The multi-cylinder rotary compressor A includes a compressor body A1 and an accumulator A2. The compressor main body A1 is a device that compresses a gas refrigerant that is a working fluid, and the accumulator A2 is a device that separates the gas refrigerant and the liquid refrigerant.

  The compressor main body A1 has a cylindrical sealed case 1, the compression mechanism portion 2 is accommodated in the lower portion of the sealed case 1, and the electric motor portion 3 is accommodated in the upper portion of the sealed case 1. The compression mechanism unit 2 and the electric motor unit 3 are connected via a rotating shaft 4 extending in the vertical direction, and the compression mechanism unit 2 is driven by a driving force generated in the electric motor unit 3.

  The compression mechanism part 2 has the 1st cylinder 5a located in the lower part side, and the 2nd cylinder 5b located in the upper part side. A bearing 6 is attached to the lower end surface of the first cylinder 5a, and a bearing 7 is attached to the upper end surface of the second cylinder 5b. A partition plate 8 is interposed between the first cylinder 5a and the second cylinder 5b.

  The rotary shaft 4 is pivotally supported by bearings 6 and 7 and is provided so as to penetrate through the first and second cylinders 5a and 5b. A first eccentric part 9a located in the first cylinder 5a and a second eccentric part 9b located in the second cylinder 5b are formed on the rotating shaft 4 with a phase difference of 180 °. The first eccentric portion 9a and the second eccentric portion 9b are formed to have the same diameter, the first eccentric portion 9a is fitted with a cylindrical first roller 10a, and the second eccentric portion 9b has a cylindrical second shape. The roller 10b is fitted.

  A first cylinder chamber 11a is formed inside the first cylinder 5a. The first cylinder chamber 11a is a space in which both ends in the vertical direction are covered with the partition plate 8 and the bearing 6 to compress the gas refrigerant. Inside the second cylinder 5b, a second cylinder chamber 11b is formed in which both ends in the vertical direction are covered with the bearings 7 and the partition plate 8 and serve as a space for compressing the gas refrigerant. First and second rollers 10a and 10b are accommodated in the first and second cylinder chambers 11a and 11b. The first and second rollers 10a and 10b are provided so as to be eccentrically rotated while a part of the outer peripheral surface is in line contact with the inner peripheral surfaces of the first and second cylinder chambers 11a and 11b.

  Disposed on the bearing 7 are double-pumped discharge mufflers 12. The discharge muffler 12 is provided on the bearing 7 and covers a discharge valve mechanism 13 that is opened when the pressure of the gas refrigerant in the second cylinder chamber 11b becomes a set value or more. The discharge muffler 12 is formed with a discharge hole (not shown) communicating with the inside of the sealed case 1. A single discharge muffler 14 is attached to the bearing 6. The discharge muffler 14 is provided on the bearing 6 and covers a discharge valve mechanism (not shown) that is opened when the pressure of the gas refrigerant in the first cylinder chamber 11a exceeds a set value.

  A discharge gas guide path (not shown) that connects the inside of the discharge muffler 12 and the inside of the discharge muffler 14 is formed across the bearing 6, the first cylinder 5a, the partition plate 8, the second cylinder 5b, and the bearing 7. Yes. As a result, the high-pressure gas refrigerant discharged from the first cylinder chamber 11a into the discharge muffler 14 flows through the discharge gas guide path, flows into the discharge muffler 12, and is compressed in the second cylinder chamber 11b. It is discharged into the sealed case 1 together with the high-pressure gas refrigerant.

  An oil reservoir 15 in which lubricating oil is stored is formed at the bottom of the sealed case 1. In FIG. 1, the solid line across the flange portion of the bearing 7 indicates the oil level of the lubricating oil stored in the oil reservoir 15. Almost all of the compression mechanism 2 is immersed in the lubricating oil stored in the oil reservoir 15.

  The structure of the compression mechanism part 2 is demonstrated based on FIG. A first blade groove 16a having one end communicating with the first cylinder chamber 11a and a first blade back chamber 17a communicating with the other end of the first blade groove 16a are formed in the first cylinder 5a. . A first blade 18a is slidably fitted in the first blade groove 16a. The first blade 18a slides toward and away from the first roller 10a that rotates eccentrically in the first cylinder chamber 11a (not shown in FIG. 2, refer to FIG. 1), and the tip is the outer periphery of the first roller 10a. When contacting the surface, the inside of the first cylinder chamber 11a is divided into two spaces. The first blade back chamber 17a is located on the rear end side of the first blade 18a. In the first blade back chamber 17a, the tip of the first blade 18a is in contact with the outer peripheral surface of the first roller 10a. The pressure for sliding (pressure by the high-pressure gas refrigerant) is guided through a back pressure introduction pipe described later.

  In the back of the first blade back chamber 17a, the first blade 18a is magnetically adsorbed when the first cylinder 5a enters an uncompressed operation state (cylinder state) in which the compression of the gas refrigerant is stopped as will be described later. A permanent magnet 20 and a holding member 21 that holds the permanent magnet 20 are accommodated.

  A second blade groove 16b having one end communicating with the second cylinder chamber 11b and a second blade back chamber 17b communicating with the other end of the second blade groove 16b are formed in the second cylinder 5b. . A second blade 18b is slidably fitted in the second blade groove 16b. The second blade 18b slides toward and away from the second roller 10b (not shown in FIG. 2; see FIG. 1) that rotates eccentrically in the second cylinder chamber 11b, and the tip is the outer periphery of the second roller 10b. When contacting the surface, the inside of the second cylinder chamber 11b is divided into two spaces. The second blade back chamber 17b is located on the rear end side of the second blade 18b. A lateral hole 22 is formed in the wall portion of the second cylinder 5b, one end communicating with the second blade back chamber 17b and the other end communicating with the outer peripheral surface of the second cylinder 5b. The member 23 is accommodated. The spring member 23 accommodated in the horizontal hole 22 is in contact with the rear end side of the second blade 18b. Due to this contact, the second blade 18b is maintained in a state in which its tip is always in contact with the outer peripheral surface of the second roller 10b by the biasing force of the spring member 23.

  Each of the first and second blades 18a and 18b has a substantially arcuate shape in the plan view of the respective leading ends thereof, and the leading ends of the first and second blades 18a and 18b appear and disappear in the first and second cylinder chambers 11a and 11b. The portion is formed to have a size that appears and disappears in the first and second blade back chambers 17a and 17b.

First and second rollers in which the first and second blades 18a and 18b protrude into the first and second cylinder chambers 11a and 11b and the tips thereof are located in the first and second cylinder chambers 11a and 11b. When abutting against the outer peripheral surfaces of 10a and 10b, the tip portions of the first and second blades 18a and 18b are in line contact regardless of the rotation angles of the first and second rollers 10a and 10b. The first and second cylinder chambers 11a and 11b are partitioned into two spaces by the tips of the first and second blades 18a and 18b coming into contact with the outer peripheral surfaces of the first and second rollers 10a and 10b. Is done. By dividing the inside of the first and second cylinder chambers 11a and 11b into two spaces, the volume of these two spaces is changed by the eccentric rotation of the first and second rollers 10a and 10b, and the volume is increased. The gradually decreasing one compartment becomes the high-pressure side and the gas refrigerant is compressed, and the other compartment becomes the low-pressure side.

  Returning to FIG. The first blade back chamber 17a of the first cylinder 5a is formed at a position protruding outward from the peripheral end of the flange portion of the bearing 6, and is formed to penetrate the first cylinder 5a in the vertical direction. The first blade back chamber 17 a has an upper surface side opening portion covered with a partition plate 8 and a lower surface side opening portion covered with a closing member 24. Therefore, the first blade back chamber 17 a has a sealed structure in which the upper and lower openings are closed by the partition plate 8 and the closing member 24. The second blade back chamber 17 b has a lower surface side opening portion covered with the partition plate 8, but the upper surface opening portion communicates with the space inside the sealed case 1. Accordingly, the pressure in the second blade back chamber 17b is the same as the pressure in the sealed case 1.

  A side end surface of the closing member 24 on the bearing 6 side is formed in a shape along the peripheral end surface of the flange portion of the bearing 6, and one end of a back pressure introducing tube 25 is connected to the opposite side end surface. Is communicated with the first blade back chamber 17a. The other end of the back pressure introduction pipe 25 communicates with a pressure switching valve, which will be described later, and a pressure buffering space portion 25 a having an internal space expanded from the back pressure introduction pipe 25 is provided in the middle of the back pressure introduction pipe 25. Is provided.

  Further, a check valve mechanism 26 is attached to the closing member 24. As shown in FIG. 3, the check valve mechanism 26 includes a valve pressing member 29 that is fixed in position and a flexible valve body 30, and the valve restraining member 29 and the valve body 30 are connected to each other. It is fixed to the closing member 24 with mounting bolts 31. The closing member 24 is fixed to a first cylinder (not shown) by mounting bolts 28.

  4 is a cross-sectional view taken along line XX in FIG. When the closing member 24 is attached to the first cylinder 5a, the closing member 24 includes a recess 32 located on the side facing the first cylinder 5a, a back pressure introduction pipe 25 (see FIG. 1), and the recess 32. A communicating hole portion 33, and a communication passage 34 communicating the recess 32 and the inside of the sealed case 1 (internal space of the sealed case 1) are formed. A check valve mechanism 26 is attached to the leading end side of the communication path 34. The recess 32 is formed at a position where the blade back chamber 17a and the back pressure introduction pipe 25 communicate with each other.

  When the first cylinder 5a is in the compression operation state, the first blade 18a slides (advances) from the first blade back chamber 17a side to the first cylinder chamber 11a side to enlarge the volume of the first blade back chamber 17a. In this case, the pressure in the first blade back chamber 17a becomes equal to or lower than the pressure in the sealed case 1, and the pressure in the recess 32 communicated with the first blade back chamber 17a also becomes lower than the pressure in the sealed case 1. The valve body 30 closes the communication passage 34.

  On the other hand, when the first blade 18a slides (retreats) from the first cylinder chamber 11a side to the first blade back chamber 17a side to reduce the volume of the first blade back chamber 17a, the inside of the first blade back chamber 17a The pressure in the recess 32 connected to the first blade back chamber 17a also becomes equal to or higher than the pressure in the sealed case 1, and the valve body 30 opens the communication passage 34. This prevents the pressure in the first blade back chamber 17a from becoming excessive. In particular, it has a great effect on the suppression of pressure rise when liquid fluid such as lubricating oil or liquid refrigerant exists in the first blade back chamber 17a and the back pressure introduction pipe 25. The valve pressing member 29 regulates the maximum opening when the valve body 30 opens the communication path 34. Further, the valve body 30 also closes the communication passage 34 even in a closed cylinder state in which a low-pressure gas refrigerant is guided into the first blade back chamber 17a.

  Returning again to FIG. A discharge pipe 35 that discharges the high-pressure gas refrigerant in the sealed case 1 to the outside of the sealed case 1 is connected to the upper end of the sealed case 1 of the compressor main body A1. A condenser 36, an expansion device 37, an evaporator 38, and an accumulator A2 are sequentially connected to the discharge pipe 35. And the refrigeration cycle apparatus S is comprised by carrying out piping connection of these compressor main bodies A1, the condenser 36, the expansion apparatus 37, the evaporator 38, and the accumulator A2 one by one.

  The accumulator A2 and the first and second cylinder chambers 11a and 11b of the compressor main body A1 are communicated with each other via a suction pipe 40. The refrigerant that has flowed into the accumulator A2 is separated into a gas refrigerant and a liquid refrigerant in the accumulator A2, and the separated low-pressure gas refrigerant flows through the suction pipe 40, and further, a flow (not shown) formed in the partition plate 8. It flows through the passage and is sucked into the first and second cylinder chambers 11a and 11b.

  The other end of the back pressure introduction pipe 25 whose one end communicates with the first blade back chamber 17a extends to a position above the upper end of the sealed case 1 and the upper end of the accumulator A2, and its tip is a pressure switching unit. A certain pressure switching valve 41 is communicated.

  The pressure switching valve 41 switches the low-pressure or high-pressure gas refrigerant guided to the first blade back chamber 17a through the back pressure introduction pipe 25. The pressure switching valve 41 has four ports (first port Pa, second port Pb, third port Pc, and fourth port Pd), and one end of the first port Pa is connected to the discharge pipe 35. The other end of the high-pressure gas refrigerant introduction pipe 42 is communicated. The second port Pb communicates with the other end of the back pressure introduction pipe 25 whose one end communicates with the first blade back chamber 17a. The third port Pc communicates with the other end of a low-pressure gas refrigerant introduction pipe 43 that is a working fluid introduction pipe with one end communicating with the suction pipe 40. The fourth port Pd is always closed by the plug body 44.

  Inside the pressure switching valve 41, a valve body 45 having an inverted U-shaped passage is movably provided. The valve body 45 has a position where the third port Pc and the fourth port Pd communicate with each other as indicated by a solid line, and a position where the second port Pb and the third port Pc communicate with each other as indicated by a broken line. It is possible to switch electromagnetically. The first port Pa is always open.

  When the valve body 45 is located at a position indicated by a solid line, the first port Pa and the second port Pb are communicated, and the third port Pc and the fourth port Pd are communicated. However, since the fourth port Pd is always closed by the plug body 44, only the communication between the first port Pa and the second port Pb remains as the communication state in the pressure switching valve 41.

  When the valve body 45 moves to the position indicated by the broken line, the second port Pb and the third port Pc are communicated with each other via the valve body 45, and the first port Pa and the fourth port Pd are communicated with each other. However, since the fourth port Pd is always closed by the plug body 44, only the communication between the second port Pb and the third port Pc remains as the communication state in the pressure switching valve 41.

  In this embodiment, as the pressure switching valve 41 which is a pressure switching unit, a cost reduction is achieved by diverting a standard four-way switching valve used in a refrigeration cycle constituting a normal heat pump air conditioner. . However, a similar effect can be obtained by using a three-way valve instead of the pressure switching valve 41 or combining a plurality of on-off valves as the pressure switching unit.

  The part of the suction pipe 40 where one end of the low-pressure gas refrigerant introduction pipe 43 communicates is a part located downstream of the accumulator A2 along the flow direction of the gas refrigerant in the refrigeration cycle apparatus S, and at least the second cylinder This is a portion through which the gas refrigerant supplied into the chamber 11b flows. During this operation of the multi-cylinder rotary compressor A, a low-pressure gas refrigerant always flows through this portion.

  The low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 are formed to have a smaller diameter than the suction pipe 40. The connection between the suction pipe 40 and the low-pressure gas refrigerant introduction pipe 43 is performed by performing hole processing on the suction pipe 40 and welding so that the low-pressure gas refrigerant introduction pipe 43 communicates with the hole.

  In such a configuration, in the multi-cylinder rotary compressor A, the high-pressure gas refrigerant compressed by the compression mechanism unit 2 is discharged into the sealed case 1, and the high-pressure gas refrigerant in the sealed case 1 is discharged into the discharge pipe 35. Is supplied to the condenser 36 side, and the refrigeration cycle apparatus S is operated.

  Further, this multi-cylinder rotary compressor A has a full-capacity operation in which the gas refrigerant is compressed by both the first cylinder 5a and the second cylinder 5b, and the second cylinder 5b alone with the first cylinder 5a in a closed state. It is possible to switch to a capacity reduction operation for performing compression, and this full capacity operation and capacity reduction operation will be described. Switching between the full capacity operation and the capacity reduction operation is performed by switching the position of the valve body 45 of the pressure switching valve 41.

  First, the case of full capacity operation will be described. During full capacity operation, the valve body 45 is moved to the position indicated by the solid line in FIG. By moving the valve body 45 to the position indicated by the solid line, the first port Pa and the second port Pb are communicated, and the third port Pc is closed. By connecting the first port Pa and the second port Pb, the high-pressure gas refrigerant introduction pipe 42 and the back pressure introduction pipe 25 are communicated, and the high-pressure gas refrigerant discharged from the sealed case 1 to the discharge pipe 35. Part of the gas flows through the high pressure gas refrigerant introduction pipe 42 and the back pressure introduction pipe 25 and is guided to the first blade back chamber 17a.

  When the high-pressure gas refrigerant is guided to the first blade back chamber 17a, this pressure acts as a back pressure on the rear end portion of the first blade 18a. Since this back pressure is higher than the pressure of the low-pressure gas refrigerant sucked into the first cylinder chamber 11a through the suction pipe 40, the tip of the first blade 18a is brought into contact with the outer peripheral surface of the first roller 10a, The inside of the first cylinder chamber 11a is partitioned into two spaces by the first blade 18a.

  A low-pressure gas refrigerant is sucked into the first cylinder chamber 11a partitioned into two spaces through the suction pipe 40 as the first roller 10a rotates eccentrically. The low-pressure gas refrigerant sucked into the first cylinder chamber 11a is compressed and becomes high pressure with the eccentric rotation of the first roller 10a, and the high-pressure gas refrigerant is discharged into the discharge muffler 14.

  In the second cylinder 5b, one end side of the spring member 23 is in contact with the rear end portion of the first blade 18b. Then, the biasing force of the spring member 23 and the high pressure in the sealed case 1 act as back pressure on the first blade 18b, the tip of the second blade 18b is always in contact with the outer peripheral surface of the second roller 10b, and the second The inside of the cylinder chamber 11b is partitioned into two spaces by the second blade 18b.

  A low-pressure gas refrigerant is sucked into the second cylinder chamber 11b partitioned into two spaces through the suction pipe 40 along with the eccentric rotation of the second roller 10b. The low-pressure gas refrigerant sucked into the second cylinder chamber 11b is compressed and increased in pressure with the eccentric rotation of the second roller 10b, and the high-pressure gas refrigerant is discharged into the discharge muffler 12. The high-pressure gas refrigerant discharged into the discharge muffler 12 merges with the high-pressure gas refrigerant flowing into the discharge muffler 12 after being discharged into the discharge muffler 14 and discharged into the sealed case 1.

  As described above, during full capacity operation, the first cylinder 5a and the second cylinder 5b are both in the compression operation state, and the gas refrigerant is compressed.

  Next, a description will be given of the capacity reduction operation. During the capacity reduction operation, the valve body 45 is moved to a position indicated by a broken line in FIG. By moving the valve body 45 to the position indicated by the broken line, the second port Pb and the third port Pc are communicated with each other, and the first port Pa is not communicated with anything. By connecting the second port Pb and the third port Pc, the low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 are communicated, and a part of the low pressure gas refrigerant flowing in the suction pipe 40 is low pressure gas. The refrigerant flows through the refrigerant introduction pipe 43 and the back pressure introduction pipe 25 and is guided to the first blade back chamber 17a.

  Since the low pressure gas refrigerant is guided to the first blade back chamber 17a and this pressure is the same as the pressure of the gas refrigerant sucked into the first cylinder chamber 11a, the first blade 18a is connected to the first roller 10a. The tip of the first blade 18a is not brought into contact with the outer peripheral surface of the first roller 10a without being biased in the direction. For this reason, the inside of the first cylinder chamber 11a is not partitioned into two spaces, and even if the first roller 10a rotates eccentrically in the first cylinder chamber 11a, the low-pressure gas refrigerant is not sucked into the first cylinder chamber 11a. The gas refrigerant is not compressed in the first cylinder chamber 11a, and the first cylinder 5a is in an uncompressed state (cylinderless state).

  On the other hand, in the second cylinder chamber 11b, the tip of the second blade 18b is brought into contact with the outer peripheral surface of the second roller 10b by the force of the spring member 23 and the high pressure in the sealed case, and the gas refrigerant is compressed.

  As described above, during the capacity reduction operation, only the second cylinder 5b is in the compression operation state, the gas refrigerant is compressed, and the first cylinder 5a is in the cylinder resting state, and the compression of the gas refrigerant is stopped.

  When the first cylinder 5a is in a cylinder resting state, the first blade 18a is magnetically attracted to the permanent magnet 20 accommodated in the blade back chamber 17a.

  During the capacity reduction operation, the pressure in the first cylinder chamber 11a of the first cylinder 5a that is in the cylinder-cylinder state is lower than the pressure in the sealed case 1. For this reason, in the first cylinder 5a in the cylinder resting state, the lubricating oil stored in the oil reservoir 15 in the sealed case 1 is changed due to the pressure difference between the first cylinder chamber 11a and the sealed case 1. The first cylinder 5a enters the first cylinder chamber 11a from the gap portion of the cylinder 5a. The lubricating oil that has entered the first cylinder chamber 11a further enters the first blade back chamber 17a via the first blade groove 16a. The lubricating oil that has entered the blade back chamber 17 a passes through the recess 32, passes through the back pressure introduction pipe 25, the pressure switching valve 41 and the low pressure gas refrigerant introduction pipe 43, and is sucked into the suction pipe 40. The lubricating oil sucked into the suction pipe 40 flows into the second cylinder chamber 11b together with the low-pressure gas refrigerant flowing through the suction pipe 40, and is sealed together with the gas refrigerant compressed to the high pressure by the second cylinder 5b. 1 is discharged.

  As described above, even when the lubricating oil in the sealed case 1 enters the first cylinder chamber 11a and the first blade back chamber 17a during the capacity reduction operation, the lubricating oil is used for the back pressure introduction pipe 25 and the low pressure gas refrigerant introduction pipe. 43 and the suction pipe 40 are returned to the sealed case 1 and do not accumulate in the accumulator A2. Therefore, it is possible to prevent the lubricating oil in the sealed case 1 from being insufficient, and it is possible to prevent the sliding portion of the compression mechanism unit 2 from being poorly lubricated due to the insufficient lubricating oil in the sealed case 1. it can. Further, it is not necessary to predict that the lubricating oil is insufficient in the sealed case 1 during the capacity reduction operation, and it is not necessary to increase the amount of the lubricating oil stored in the sealed case 1 in advance. .

During full-capacity operation in which the first cylinder 5a is in a compression operation state, the first blade 18a whose tip is in contact with the outer peripheral surface of the first roller 10a reciprocates with the eccentric rotation of the first roller 10a. Slide. When the first blade 18a slides in the direction of reducing the volume of the first blade back chamber 17a, the pressure in the first blade back chamber 17a increases. Moreover, when the 1st blade 18a slides in the direction which expands the volume of the 1st blade back chamber 17a, the pressure in the 1st blade back chamber 17a falls. In this way, the pressure fluctuates and pressure pulsation occurs. However, in this embodiment, since the pressure buffering space 25a is provided in the middle of the back pressure introduction pipe 25, even if the pressure in the first blade back chamber 17a fluctuates and pulsation occurs, the pressure pulsation is the pressure It is relaxed by the buffer space 25a. Therefore, it is possible to suppress the pressure pulsation from being transmitted to the back pressure introduction pipe 25, the high pressure gas refrigerant introduction pipe 42 and the discharge pipe 35. Thereby, it can suppress that a vibration and chatter noise generate | occur | produce in the back pressure introduction pipe | tube 25, the high pressure gas refrigerant introduction pipe | tube 42, and the discharge pipe 35. FIG.

  Regarding the diameters of the low pressure gas refrigerant introduction pipe 43, the back pressure introduction pipe 25, and the suction pipe 40, the low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 are formed to have a smaller diameter than the suction pipe 40. For this reason, the amount of lubricating oil staying in the back pressure introduction pipe 25 or the low pressure gas refrigerant introduction pipe 43 can be reduced during the capacity reduction operation in which the first cylinder 5a is in the closed cylinder state. The decrease in the lubricating oil inside can be suppressed.

  In addition, when the suction pipe 40 is perforated and the low-pressure gas refrigerant introduction pipe 43 and the suction pipe 40 are welded so that the low-pressure gas refrigerant introduction pipe 43 communicates with the hole, the low-pressure gas refrigerant introduction pipe 43 is inhaled. Since the diameter is smaller than that of the tube 40, the welding operation can be easily performed.

  The check valve mechanism 26 provided in the closing member 24 allows the pressure of the first blade back chamber 17a to be within the sealed case 1 due to the sliding of the first blade 18a during full capacity operation in which the first cylinder 5a is in the compression operation state. When the pressure becomes larger than the pressure, the valve body 30 opens the communication path 34. Thereby, the pressure in the raised first blade back chamber 17a can be released into the sealed case 1, and the pressure in the raised first blade back chamber 17a is prevented from being transmitted to the back pressure introduction pipe 25 side. Can do. Therefore, by providing the check valve mechanism 26, it is possible to suppress the pulsation generated in the first blade back chamber 17a from being transmitted to the back pressure introduction pipe 25, the high pressure gas refrigerant introduction pipe 42, and the discharge pipe 35. Thereby, it is possible to suppress the occurrence of vibration and chatter noise in the back pressure introduction pipe 25, the high-pressure gas refrigerant introduction pipe 42, and the discharge pipe 35 due to the pressure fluctuation in the first blade back chamber 17a.

  The check valve mechanism 26 is also used when the pressure in the first blade back chamber 17a is equal to or lower than the pressure in the sealed case 1, or when the low pressure gas refrigerant is introduced into the first blade back chamber 17a. In the case of the state, the valve body 30 closes the communication path 34. For this reason, it is possible to prevent the lubricating oil in the sealed case 1 from flowing into the first blade back chamber 17a, which has a pressure lower than the pressure in the sealed case 1, from the communication path 34.

(Second Embodiment)
A second embodiment will be described with reference to FIG. In addition, the same component as the component demonstrated in 1st Embodiment is shown with the same code | symbol, and the overlapping description is abbreviate | omitted.

  The basic configuration of the multi-cylinder rotary compressor B of the second embodiment is the same as the multi-cylinder rotary compressor A of the first embodiment, and the multi-cylinder rotary compressor B includes a compressor body B1 and And an accumulator B2. The second embodiment differs from the first embodiment in a piping structure for supplying a low-pressure gas refrigerant from the accumulator B2 to the compressor body B1, and the first and second parts of the compressor body B1. The cylinder chambers 11a and 11b and the accumulator B2 are communicated with each other by two suction pipes 40a and 40b.

One end of one suction pipe 40a passes through the sealed case 1 and communicates with the first cylinder chamber 11a of the first cylinder 5a. One end of the other suction pipe 40b passes through the sealed case 1 and communicates with the second cylinder chamber 11b of the second cylinder 5b.

  Accordingly, the low-pressure gas refrigerant is always sucked into the second cylinder chamber 11b of the second cylinder 5b, which is always in the compression operation state, through the suction pipe 40b. On the other hand, in the first cylinder chamber 11a of the first cylinder 5a, when the first cylinder 5a is in the closed cylinder state, the low-pressure gas refrigerant is not sucked from the suction pipe 40a, but only when the compression operation is performed. Low-pressure gas refrigerant is sucked from 40a.

  One end of the low-pressure gas refrigerant introduction pipe 43 communicates with a position downstream of the accumulator B2 along the flow direction of the gas refrigerant in the refrigeration cycle apparatus S of the suction pipe 40b. During the operation of the multi-cylinder rotary compressor B, the gas refrigerant sucked into the second cylinder chamber 11b always flows through the suction pipe 40b. Then, when the pressure switching valve 41 is switched to connect the low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 so that the first cylinder 5a is in a closed state, the low pressure gas refrigerant flowing in the suction pipe 40b. However, it flows through the low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 and is guided to the first blade back chamber 17a.

  In such a configuration, during full capacity operation, the valve body 45 is moved to the position indicated by the solid line in FIG. By moving the valve body 45 to the position indicated by the solid line, the first port Pa and the second port Pb are communicated with each other, the high-pressure gas refrigerant introduction pipe 42 and the back pressure introduction pipe 25 are communicated, and the third port Pc. Is closed. By connecting the first port Pa and the third port Pc, the high-pressure gas refrigerant introduction pipe 42 and the back pressure introduction pipe 25 are communicated, and the high-pressure gas refrigerant discharged from the sealed case 1 to the discharge pipe 35. Part of the gas flows through the high pressure gas refrigerant introduction pipe 42 and the back pressure introduction pipe 25 and is guided to the first blade back chamber 17a.

  When the high-pressure gas refrigerant is guided to the first blade back chamber 17a, this pressure acts as a back pressure on the rear end portion of the first blade 18a, and the front end portion of the first blade 18a is the outer peripheral surface of the first roller 10a. The gas refrigerant is compressed in the first cylinder 5a. In the second cylinder 5b, one end of the spring member 23 abuts on the rear end of the second blade 18b and acts as a back pressure, and the tip of the second blade 18b contacts the outer peripheral surface of the second roller 10b. The gas refrigerant is compressed in the second cylinder 5b.

  Next, the valve body 45 is moved to the position indicated by the broken line in FIG. When the valve body 45 moves to the position indicated by the broken line, the second port Pb and the third port Pc are communicated with each other, and the low pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 are communicated to flow through the suction pipe 40b. Part of the low-pressure gas refrigerant flows through the low-pressure gas refrigerant introduction pipe 43 and the back pressure introduction pipe 25 and is guided to the first blade back chamber 17a.

  When the low-pressure gas refrigerant is guided to the first blade back chamber 17a, the tip of the first blade 18a does not contact the outer peripheral surface of the first roller 10a, and the compression of the gas refrigerant in the first cylinder 5 is stopped. The first cylinder 5a is in a cylinder resting state.

During the capacity reduction operation, the pressure in the first cylinder chamber 11a of the first cylinder 5a that is in the cylinder-cylinder state is lower than the pressure in the sealed case 1. For this reason, in the cylinder resting state, due to the pressure difference between the first cylinder chamber 11a and the sealed case 1, the lubricating oil stored in the oil reservoir 15 in the sealed case 1 is the gap portion of the first cylinder 5a. Enters the first cylinder chamber 11a. The lubricating oil that has entered the first cylinder chamber 11a further enters the first blade back chamber 17a via the first blade groove 16a. The lubricating oil that has entered the blade back chamber 17a flows through the back pressure introduction pipe 25 and the low pressure gas refrigerant introduction pipe 43, and is sucked into the suction pipe 40b. The lubricating oil sucked into the suction pipe 40b flows into the second cylinder chamber 11b together with the low-pressure gas refrigerant flowing through the suction pipe 40b, and is sealed together with the gas refrigerant compressed to the high pressure by the second cylinder 5b. 1 is discharged.

  As described above, during the capacity reduction operation, even if the lubricating oil in the sealed case 1 enters the first cylinder chamber 11a, the lubricating oil passes through the back pressure introduction pipe 25, the low pressure gas refrigerant introduction pipe 43, and the suction pipe 40b. Through the airtight case 1 and does not accumulate in the accumulator B2. Accordingly, the lubricating oil in the sealed case 1 is accumulated in the accumulator B2 during the capacity reduction operation, so that it is possible to prevent the lubricating oil from being insufficient in the sealed case 1, and the sliding portion of the compression mechanism unit 2 can be prevented. It is possible to prevent the lubrication from becoming defective. Further, it is not necessary to increase the amount of lubricating oil stored in the sealed case 1 in advance by predicting that the lubricating oil is insufficient in the sealed case 1 during the capacity reduction operation, and the amount of lubricating oil used can be suppressed.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Sealing case, 2 ... Compression mechanism part, 3 ... Electric motor part, 5a ... 1st cylinder, 5b ... 2nd cylinder, 10a ... 1st roller, 11a ... 1st cylinder chamber, 11b ... 2nd cylinder chamber, 17a ... 1st blade back chamber, 18a ... 1st blade, 25 ... Back pressure introduction pipe, 25a ... Pressure buffer space part, 26 ... Check valve mechanism, 34 ... Communication path, 40 ... Suction pipe, 40a ... Suction pipe, 40b ... Suction pipe, 41 ... pressure switching valve (pressure switching section), 43 ... low pressure gas refrigerant introduction pipe (low pressure working fluid introduction pipe), A ... multi-cylinder rotary compressor, A2 ... accumulator, B ... multi-cylinder rotary compressor , B2 ... Accumulator, S ... Refrigeration cycle apparatus

Claims (3)

A first cylinder that has a first cylinder chamber and can be switched between a compression operation state and a non-compression operation state of a closed cylinder; and a second cylinder that has a second cylinder chamber and is always in a compression operation state; A compression mechanism that compresses a low-pressure working fluid supplied from an accumulator through a suction pipe, an electric motor that drives the compression mechanism, and a sealed case that accommodates the compression mechanism and the electric motor The first cylinder is provided with a first roller that rotates eccentrically in the first cylinder chamber, and is slidable in a direction in which the first cylinder comes in contact with and separates from the first roller, and a tip portion is an outer peripheral surface of the first roller. A first blade that divides the first cylinder chamber into two spaces when in contact with the first blade, and a rear end side of the first blade, in a direction in which the first blade comes in contact with and separates from the first roller. Pressure to slide In the first blade back chamber and has a multi-cylinder rotary compressor for discharging a high-pressure working fluid compressed in the first and second cylinder chamber in said sealed case for supplying,
As the suction pipe, two suction pipes for supplying a low pressure working fluid to the first cylinder chamber and the other suction pipe for supplying a low pressure working fluid to the second cylinder chamber are provided.
A back pressure introduction pipe having one end communicating with the first blade back chamber;
A pressure switching unit that communicates with the other end of the back pressure introduction pipe, and switches the low pressure or high pressure working fluid to the first blade back chamber through the back pressure introduction pipe;
Wherein the pressure switching unit one end of which communicates with the first cylinder the back-pressure front's rating second cylinder chamber from the other end the accumulator low pressure of the working fluid with communicates with the pipe when uncompressed operating conditions A working fluid introduction pipe communicated with the other suction pipe to be supplied to
With
The working fluid introduction pipe and the back pressure introduction pipe are formed with a smaller diameter than the other suction pipe,
A high-pressure working fluid discharged from the discharge pipe is provided between a discharge pipe provided at the upper part of the sealed case and discharges the high-pressure working fluid in the sealed case to the outside of the sealed case. A high-pressure gas refrigerant introduction pipe leading to the pressure switching unit is connected;
The compression mechanism portion includes a communication path that communicates the first blade back chamber and the inside of the sealed case, and a check valve mechanism that opens and closes the communication path.
The check valve mechanism closes the communication path when the first blade slides in the direction of enlarging the volume of the first blade back chamber when the first cylinder is in a compression operation state, The multi-cylinder rotary compressor is configured to open the communication path when one blade slides in a direction to reduce the volume of the first blade back chamber.   The multi-cylinder rotary compressor according to claim 1, wherein a pressure buffering space having an expanded internal space is provided in the middle of the back pressure introduction pipe. A refrigeration cycle apparatus comprising the multi-cylinder rotary compressor according to claim 1, a condenser, an expansion device, and an evaporator to constitute a refrigeration cycle .

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