JP2006169979A - Compression system and refrigerating unit using this compression system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a collision sound of a second vane when switching to a second operation mode from a first operation mode, while improving performance by improving compression efficiency in a second rotary compression element, in a compression system having a multi-cylinder rotary compression element usable by switching to the second operation mode of allowing only a first rotary compression element to substantially perform compression work. <P>SOLUTION: In the first operation mode, oil of an oil reservoir 13 in a sealed vessel 12 is supplied to a back pressure chamber 72A of the second vane 52. In the second operation mode, suction side pressure of the first rotary compression element 32 is impressed on the back pressure chamber 72A of the second vane 52. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a compression system including a multi-cylinder rotary compressor and a refrigeration apparatus using the same.

  Conventionally, this type of compression system includes a multi-cylinder rotary compressor and a control device for controlling the operation of the multi-cylinder rotary compressor. This multi-cylinder rotary compressor, for example, a two-cylinder rotary compressor provided with first and second rotary compression elements, includes a first and a second driven by a drive element and a rotary shaft of the drive element in a sealed container. 2 rotary compression elements are housed. The first and second rotary compression elements include first and second cylinders, and first and second rollers that are fitted to eccentric portions formed on the rotation shaft and rotate eccentrically in the cylinders, respectively. The first and second vanes are in contact with the first and second rollers and divide the inside of each cylinder into a low pressure chamber side and a high pressure chamber side, respectively. The first and second vanes are always urged by the spring members to the first and second rollers, respectively.

Then, when the drive element is driven by the control device, the low-pressure refrigerant gas is sucked into the low-pressure chamber side of each cylinder of the first and second rotary compression elements from the suction passage, and the operation of each roller and each vane Each is compressed into high-temperature and high-pressure refrigerant gas, discharged from the high-pressure chamber side of each cylinder to the discharge silencer chamber through the discharge port, then discharged into the sealed container and discharged to the outside (for example, , See Patent Document 1).
JP-A-5-99172

  In such a compression system equipped with a multi-cylinder rotary compressor, when the first and second cylinders perform compression operation in a small capacity range such as during light load or low speed rotation, the displacement volume of both cylinders Since the refrigerant gas has to be sucked in and compressed, the control device is operated with the rotational speed of the drive element lowered by that amount. However, if the rotational speed is too low, the operation efficiency of the drive element is lowered, and there is a problem that the leakage loss is increased and the compression efficiency is also lowered.

  For this reason, in view of the problem, a compression system has been developed that can switch between a one-cylinder operation and a two-cylinder operation according to the capacity. That is, one of the spring members that urge the first and second vanes of the multi-cylinder rotary compressor to the first and second rollers, for example, the second vane The spring member biased to the roller is deleted, and the refrigerant pressure on the discharge side of the rotary compression elements is applied as the back pressure of the second vane during the two-cylinder operation by the control device. As a result, the second vane is urged toward the second roller to perform compression work.

  On the other hand, in the small capacity region, the control device applies the refrigerant pressure on the suction side of the rotary compression elements as the back pressure of the second vane. Since this suction pressure is low, the second vane cannot be urged toward the second roller. For this reason, substantially no compression work is performed in the second rotary compression element, and the compression work of the refrigerant is performed only in the first rotary compression element.

  As described above, since the amount of refrigerant gas to be compressed can be reduced by performing the one-cylinder operation in the small capacity region, the number of revolutions can be increased accordingly. As a result, the operating efficiency of the drive element can be improved and the leakage loss can be reduced.

  However, as described above, in the second rotary compression element in which the spring member is not provided during the two-cylinder operation, there has been a problem that the refrigerant gas in the second cylinder leaks from the gap of the second vane. . In particular, at the time of low speed rotation, the amount of leak increases, leading to a significant decrease in compression efficiency.

  On the other hand, since the discharge-side pressure is applied as the back pressure of the second vane during the two-cylinder operation, the second vane is not easily retracted from the second cylinder when switching from the two-cylinder operation to the one-cylinder operation. In the meantime, the second roller collides with the second roller, and there is a disadvantage that a collision sound is generated.

  The present invention has been made to solve such a conventional technical problem, in which only the first vane is biased to the first roller by the spring member, and the rotary compression element performs the compression work. In a compression system including a multi-cylinder rotary compression element that can be used by switching between one operation mode and a second operation mode in which only the first rotary compression element performs compression work. An object of the present invention is to improve the compression efficiency of the rotary compression element to improve the performance, and to reduce the collision noise of the second vane when switching from the first operation mode to the second operation mode.

  In the compression system of the present invention, a drive element and first and second rotary compression elements driven by a rotation shaft of the drive element are accommodated in an airtight container, and the first and second rotary compression elements are The first and second cylinders, the first and second rollers fitted in the eccentric portion formed on the rotation shaft and eccentrically rotated in each cylinder, and the first and second rollers are in contact with each other. The first and second vanes that divide the inside of each cylinder into a low pressure chamber side and a high pressure chamber side, respectively, and only the first vane is urged to the first roller by a spring member to compress both rotations. A multi-cylinder rotary compressor is provided that can be used by switching between a first operation mode in which an element performs compression work and a second operation mode in which only the first rotary compression element performs compression work. In the first operation mode, the second base Supplying the oil in the oil reservoir in the closed container to the back pressure chamber of the first vane and applying the suction side pressure of the first rotary compression element to the back pressure chamber of the second vane in the second operation mode. It is.

  A compression system according to a second aspect of the present invention discharges the refrigerant compressed by the first and second rotary compression elements in the above-described invention into a sealed container.

  In the refrigeration apparatus according to the invention of claim 3, a refrigerant circuit is configured using the compression system of each of the inventions described above.

  According to the first aspect of the present invention, since the oil in the oil reservoir in the hermetic container is supplied to the back pressure chamber of the second vane in the first operation mode, the refrigerant gas leaks from the gap of the second vane. Can be reduced.

  Further, when switching from the first operation mode to the second operation mode, the collision noise of the second vane can be reduced by the oil in the back pressure chamber.

  Further, if the refrigerant compressed by the first and second rotary compression elements is discharged into the sealed container as in claim 2, oil can be easily supplied to the back pressure chamber due to the pressure difference. become.

  Furthermore, even when the oil supplied to the back pressure chamber leaks into the second cylinder, the refrigerant gas in the second cylinder is discharged into the hermetic container to separate it from the mixed oil. Therefore, oil discharge to the outside of the multi-cylinder rotary compressor can be reduced.

  As described above, the first and second rotary compression elements are switched between the first operation mode in which compression work is performed and the second operation mode in which only the first rotation compression element is in compression work is used. The performance and reliability of the multi-cylinder rotary compressor that can be improved can be improved, and the performance of the compression system can be significantly improved.

  Further, by configuring the refrigerant circuit of the refrigeration apparatus using the compression system of each of the inventions as in claim 3, it is possible to improve the operation efficiency and performance of the entire refrigeration apparatus.

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

  FIG. 1 is a longitudinal side view of an internal high-pressure rotary compressor 10 having first and second rotary compression elements as an embodiment of a multi-cylinder rotary compressor of the compression system CS of the present invention. FIG. The longitudinal side view (the cross section different from FIG. 1 is shown) of the rotary compressor 10 is shown, respectively. In addition, the compression system CS of a present Example comprises a part of refrigerant circuit of the air conditioner as a refrigeration apparatus which air-conditions a room | chamber interior.

  In each figure, the rotary compressor 10 of the embodiment is an internal high-pressure type rotary compressor, and is used as a drive element disposed in the upper side of the internal space of the sealed container 12 in a vertical cylindrical sealed container 12 made of a steel plate. An electric element 14 and a rotary compression mechanism portion 18 which is disposed below the electric element 14 and is driven by the rotary shaft 16 of the electric element 14 and which includes the first and second rotary compression elements 32 and 34 are accommodated. Yes.

  The sealed container 12 has an oil reservoir 13 at the bottom, a container body 12A that houses the electric element 14 and the rotary compression mechanism 18, and a generally bowl-shaped end cap (lid) 12B that closes the upper opening of the container body 12A. A circular mounting hole 12D is formed on the upper surface of the end cap 12B, and a terminal (wiring is omitted) 20 for supplying power to the electric element 14 is mounted in the mounting hole 12D. It has been.

  A refrigerant discharge pipe 96 is attached to the end cap 12 </ b> B, and one end of the refrigerant introduction pipe 96 communicates with the inside of the sealed container 12. A mounting base 110 is provided on the bottom of the sealed container 12.

  The electric element 14 includes a stator 22 that is welded and fixed in an annular shape along the inner peripheral surface of the upper space of the sealed container 12, and a rotor 24 that is inserted and installed inside the stator 22 with a slight gap. The rotor 24 is fixed to a rotary shaft 16 that extends in the vertical direction through the center.

  The stator 22 has a laminated body 26 in which donut-shaped electromagnetic steel plates are laminated, and a stator coil 28 wound around the teeth of the laminated body 26 by a direct winding (concentrated winding) method. Similarly to the stator 22, the rotor 24 is also formed of a laminated body 30 of electromagnetic steel plates.

  An intermediate partition plate 36 is sandwiched between the first rotary compression element 32 and the second rotary compression element 34. That is, the first rotary compression element 32 and the second rotary compression element 34 include an intermediate partition plate 36, first and second cylinders 38 and 40 disposed above and below the intermediate partition plate 36, and the first rotary compression element 32 and the second rotary compression element 34. The first and second cylinders 38, 40 are fitted to upper and lower eccentric portions 42, 44 provided on the rotary shaft 16 with a phase difference of 180 degrees, and are eccentrically rotated in the cylinders 38, 40, respectively. And first and second vanes 50 which abut against the first and second rollers 46 and 48 and divide the cylinders 38 and 40 into a low pressure chamber side and a high pressure chamber side, respectively. , 52, and an upper support member 54 and a lower support member as support members that also serve as bearings for the rotary shaft 16 by closing the upper opening surface of the first cylinder 38 and the lower opening surface of the second cylinder 40. 56.

  The first and second cylinders 38, 40 are provided with suction passages 58, 60 communicating with the insides of the first and second cylinders 38, 40, respectively. The suction passages 58, 60 are described later. Refrigerant introduction pipes 92 and 94 are connected in communication.

  A discharge muffler chamber 62 is provided above the upper support member 54, and the refrigerant gas compressed by the first rotary compression element 32 is discharged into the discharge muffler chamber 62. The discharge silencing chamber 62 has a hole through which the upper support member 54 that also serves as a bearing of the rotary shaft 16 and the rotary shaft 16 passes in the center, and covers the electric element 14 side (upper side) of the upper support member 54. It is formed in a bowl-shaped cup member 63. The electric element 14 is provided above the cup member 63 at a predetermined interval from the cup member 63.

  The lower support member 56 is provided with a discharge silencing chamber 64 formed by closing a recessed portion formed on the lower side of the lower support member 56 with a cover as a wall. That is, the discharge silencer chamber 64 is closed by the lower cover 68 that defines the discharge silencer chamber 64.

  The first cylinder 38 is formed with a guide groove 70 for accommodating the first vane 50 described above, and a spring member is provided outside the guide groove 70, that is, on the back side of the first vane 50. A storage portion 70A for storing the spring 74 is formed. The spring 74 abuts against the rear side end of the first vane 50 and constantly urges the first vane 50 toward the first roller 46. Further, for example, a discharge side pressure (high pressure) described later in the sealed container 12 is also introduced into the storage portion 70 </ b> A and applied as a back pressure of the first vane 50. The storage portion 70A is open to the guide groove 70 side and the closed container 12 (container body 12A) side, and a metal plug 137 is provided on the closed container 12 side of the spring 74 stored in the storage portion 70A. Thus, it serves to prevent the spring 74 from coming off.

  The second cylinder 40 is formed with a guide groove 72 for accommodating the second vane 52, and a back pressure chamber is formed outside the guide groove 72, that is, on the back side of the second vane 52. 72A is formed. The back pressure chamber 72A is open to the guide groove 72 side and the closed container 12 side, and a pipe 75 described later is connected to the opening of the closed container 12 side to be sealed from the inside of the closed container 12.

  Sleeves 141 and 142 are welded and fixed to the side surfaces of the container body 12A of the sealed container 12 at positions corresponding to the suction passages 58 and 60 of the first cylinder 38 and the second cylinder 40, respectively.

  One end of a refrigerant introduction pipe 92 for introducing refrigerant gas into the first cylinder 38 is inserted and connected into the sleeve 141, and one end of the refrigerant introduction pipe 92 communicates with the suction passage 58 of the upper cylinder 38. The other end of the refrigerant introduction pipe 92 is opened in the accumulator 146.

  One end of a refrigerant introduction pipe 94 for introducing refrigerant gas into the second cylinder 40 is inserted into and connected to the sleeve 142, and one end of the refrigerant introduction pipe 94 communicates with the suction passage 60 of the second cylinder 40. The other end of the refrigerant introduction pipe 94 is opened in the accumulator 146 in the same manner as the refrigerant introduction pipe 92.

  The accumulator 146 is a tank that performs gas-liquid separation of the suction refrigerant, and is attached to the upper side surface of the container body 12 </ b> A of the sealed container 12 via a bracket 147. A refrigerant introduction pipe 92 and a refrigerant introduction pipe 94 are inserted into the accumulator 146 from the bottom, and openings at the other ends are positioned above the accumulator 146, respectively. A communication pipe 148 is connected to the bottom of the accumulator 146, and oil accumulated in the accumulator 146 is returned to the oil reservoir 13 in the lower part of the sealed container 12 through the communication pipe 148. Further, one end of the refrigerant pipe 100 is inserted into the upper part of the accumulator 146.

  On the other hand, the discharge silencer chamber 64 and the discharge silencer chamber 62 communicate with the upper and lower support members 54 and 56, the first and second cylinders 38 and 40, and the intermediate partition plate 36 in the axial direction (vertical direction). It is communicated through. Then, the high-temperature and high-pressure refrigerant gas compressed by the second rotary compression element 34 and discharged to the discharge muffler chamber 64 is discharged to the discharge muffler chamber 62 through the communication passage 120, and is then discharged by the first rotary compression element 32. Merges with compressed high-temperature and high-pressure refrigerant gas.

  Further, the discharge silencer chamber 62 and the inside of the sealed container 12 are communicated with each other through a hole (not shown) penetrating the cup member 63, and the first rotary compression element 32 and the second rotary compression element 34 are compressed through this hole. The high-temperature and high-pressure refrigerant gas discharged into the discharge silencer chamber 62 is discharged into the sealed container 12.

  On the other hand, a refrigerant pipe 101 is connected to a middle portion of the refrigerant pipe 100 having one end inserted into the upper portion of the accumulator 146, and the pipe is connected to a four-way switching valve 107. One end of the pipe 102 is also connected to the oil reservoir 13 at the bottom of the sealed container 12. As described above, one end of the pipe 102 is connected to the oil reservoir 13 and rises upward therefrom, and the other end is connected to the four-way switching valve 107 in the same manner as the refrigerant pipe 101. The four-way switching valve 107 is connected to the pipe 75. The controller 210 is a control device that constitutes a part of the compression system CS of the present invention, and controls the rotational speed of the electric element 14 of the rotary compressor 10. Further, the switching of the four-way switching valve 107 is controlled.

  The four-way switching valve 107 can be switched by a solenoid coil 108. That is, when the power is OFF, the four-way switching valve 107 is in a state where the oil pipe 102 and the pipe 75 are communicated. When the power of the four-way switching valve 107 is turned on based on the ON signal from the controller 210, a magnetic field is generated in the solenoid coil 108. As a result, the four-way switching valve 107 is switched, and the refrigerant pipe 101 and the pipe 75 are communicated. Further, when an OFF signal is input from the controller 210, the power source of the four-way switching valve 107 is turned off, and the piping 102 and the piping 75 are communicated by the four-way switching valve 107 as described above.

  Next, FIG. 3 shows a refrigerant circuit diagram of the air conditioner configured using the compression system CS. That is, the compression system CS of the embodiment constitutes a part of the refrigerant circuit of the air conditioner shown in FIG. 3, and is composed of the rotary compressor 10 and the controller 210 described above. The refrigerant discharge pipe 96 of the rotary compressor 10 is connected to the inlet of the outdoor heat exchanger 152. The controller 210, the rotary compressor 10, and the outdoor heat exchanger 152 are provided in an outdoor unit (not shown) of the air conditioner. A pipe connected to the outlet of the outdoor heat exchanger 152 is connected to an expansion valve 154 as decompression means, and a pipe exiting the expansion valve 154 is connected to an indoor heat exchanger 156. The expansion valve 154 and the indoor side heat exchanger 156 are provided in an indoor unit (not shown) of the air conditioner. The refrigerant pipe 100 of the rotary compressor 10 is connected to the outlet side of the indoor heat exchanger 156.

  Note that HFC or HC refrigerants are used as refrigerants, and existing oils such as mineral oils (mineral oils), alkylbenzene oils, ether oils and ester oils are used as the lubricating oils.

  Next, the operation of the rotary compressor 10 with the above configuration will be described.

(1) First operation mode (operation at normal load or high load)
First, the first operation mode in which the rotary compression elements 32 and 34 perform compression work will be described. Based on the operation command input of the controller on the indoor unit (not shown) provided in the indoor unit described above, the controller 210 controls the rotation speed of the electric element 14 of the rotary compressor 10 and the room is in a normal load or high load state. If so, the controller 210 executes the first operation mode. Further, the four-way switching valve 107 remains off. That is, the piping 102 and the piping 75 are communicated by the four-way switching valve 107 (FIG. 4).

  When the stator coil 28 of the electric element 14 is energized through the terminal 20 and a wiring (not shown), the electric element 14 is activated and the rotor 24 rotates. By this rotation, the first and second rollers 46 and 48 are eccentrically rotated in the first and second cylinders 38 and 40 by being fitted to upper and lower eccentric portions 42 and 44 provided integrally with the rotary shaft 16.

  Thereby, the low-pressure refrigerant flows from the refrigerant pipe 100 of the rotary compressor 10 into the accumulator 146. Since the refrigerant pipe 101 is not communicated with the pipe 75 by the four-way switching valve 107 as described above, all the refrigerant passing through the refrigerant pipe 100 flows into the accumulator 146 without flowing into the pipe 75.

  The low-pressure refrigerant that has flowed into the accumulator 146 is gas-liquid separated there, and then only the refrigerant gas enters the refrigerant discharge pipes 92 and 94 opened in the accumulator 146. The low-pressure refrigerant gas that has entered the refrigerant introduction pipe 92 is sucked into the low-pressure chamber side of the first cylinder 38 of the first rotary compression element 32 through the suction passage 58.

  The refrigerant gas sucked into the low-pressure chamber side of the first cylinder 38 is compressed by the operation of the first roller 46 and the first vane 50 to become a high-temperature and high-pressure refrigerant gas, and the high-pressure chamber side of the first cylinder 38. Then, the liquid is discharged into the discharge silencer chamber 62 through a discharge port (not shown).

  On the other hand, the low-pressure refrigerant gas that has entered the refrigerant introduction pipe 94 passes through the suction passage 60 and is sucked into the low-pressure chamber side of the second cylinder 40 of the second rotary compression element 34. The refrigerant gas sucked into the low pressure chamber side of the second cylinder 40 is compressed by the operations of the second roller 48 and the second vane 52.

  At this time, since the pipe 102 and the pipe 75 are communicated by the four-way switching valve 107 as described above, the oil in the oil reservoir 13 is supplied to the back pressure chamber 72A via the pipe 102, the four-way switching valve 107, and the pipe 75. Is done. Since the oil is as high as the pressure in the sealed container 12, the high-pressure oil (hydraulic pressure) is applied as the back pressure of the second vane 52. As a result, the second vane 52 can be sufficiently urged against the second roller 48 without using a spring member.

  Conventionally, as shown in FIG. 5, a high-pressure refrigerant gas serving as the discharge side of the rotary compression elements 32 and 34 is applied as the back pressure of the second vane 52. In this case, the discharge side pressure has a large pulsation. In addition, since there is no spring member, the followability of the second vane 52 is deteriorated by this pulsation, and the refrigerant gas in the second cylinder 40 leaks from the gap of the second vane 52. . In particular, at the time of low speed rotation, since the rotation of the second roller 48 becomes slow, there is a problem that the amount of leakage increases correspondingly and the compression efficiency is remarkably lowered.

  However, in the present invention, by supplying the oil in the oil reservoir 13 in the closed container 12 to the back pressure chamber 72A of the second vane 52, the difference between the fluid of the oil and the refrigerant gas (the oil is more viscous than the refrigerant gas). High), the refrigerant gas in the second cylinder 40 is difficult to leak, so that the leakage of the refrigerant gas can be remarkably reduced. Thereby, the compression efficiency in the second rotary compression element 34 can be improved.

  The refrigerant gas compressed to high temperature and high pressure by the operation of the second roller 48 and the second vane 52 passes through the discharge port (not shown) from the high pressure chamber side of the second cylinder 40 to the discharge silencer chamber 64. Discharged. The refrigerant gas discharged to the discharge muffler chamber 64 is discharged to the discharge muffler chamber 62 via the communication path 120 and merges with the refrigerant gas compressed by the first rotary compression element 32. The merged refrigerant gas is discharged into the sealed container 12 through a hole (not shown) that penetrates the cup member 63. By discharging the refrigerant compressed by the first and second rotary compression elements 32 and 34 to the sealed container 12 in this way, the inside of the sealed container 12 can be made high-pressure, via the pipe 102. The oil in the oil reservoir 13 at the bottom of the sealed container 12 can be easily supplied to the back pressure chamber 72A using the pressure difference.

  Further, even when the oil supplied to the back pressure chamber 72A leaks into the second cylinder 40 from the gap of the second vane 52, the high-pressure refrigerant is passed through the sealed container 12 in the process. The oil mixed in the gas can be separated, and the amount of oil discharged to the outside of the rotary compressor 10 can be reduced.

  The refrigerant discharged into the sealed container 12 is discharged to the outside from a refrigerant discharge pipe 96 formed in the end cap 12B of the sealed container 12, and flows into the outdoor heat exchanger 152. Therefore, the refrigerant gas dissipates heat and is depressurized by the expansion valve 154 and then flows into the indoor heat exchanger 156. The refrigerant evaporates in the indoor heat exchanger 156 and absorbs heat from the air circulated in the room, thereby exerting a cooling action to cool the room. Then, the refrigerant repeats a cycle in which the refrigerant leaves the indoor heat exchanger 156 and is sucked into the rotary compressor 10.

  In this embodiment, high pressure oil is supplied to the back pressure chamber 72A in the first operation mode. However, the present invention is not limited to this. For example, as shown in FIG. An electromagnetic valve 105 may be provided, the electromagnetic valve 105 may be closed, and the inside of the back pressure chamber 72A may be set to an intermediate pressure. That is, after supplying oil into the back pressure chamber 72A as described above, the controller 210 closes the electromagnetic valve 105 to prevent the oil from flowing into the back pressure chamber 72A. At this time, the oil supplied to the back pressure chamber 72A remains in the back pressure chamber 72A.

  Further, the controller 210 transmits an ON signal to the four-way switching valve 107 and the power of the four-way switching valve 107 is turned on. Thereby, the magnetic field of the solenoid coil 108 is generated, the four-way switching valve 107 is switched, and the refrigerant pipe 101 and the pipe 75 are communicated. At this time, the high-pressure oil remaining in the pipe 75 enters the refrigerant pipe 101 via the four-way switching valve 107 due to the pressure difference, and enters the accumulator 146 together with the low-pressure refrigerant gas in the refrigerant pipe 100 from there. After being temporarily stored in the accumulator 146, it is returned from the communication pipe 148 to the oil reservoir 13 in the sealed container 12.

  In this case, since the solenoid valve 105 is closed, all of the suction side refrigerant flowing through the refrigerant pipe 100 flows into the accumulator 146 as described above without flowing into the back pressure chamber 72A. On the other hand, the back pressure chamber 72A flows from both the high pressure chamber side and the low pressure chamber side in the second cylinder 40 through the gap of the second vane 52. The pressure is an intermediate pressure between the suction side pressure and the discharge side pressure of the rotary compression elements 32 and 34.

  In this way, the solenoid valve 105 is provided in the pipe 75, the solenoid valve 105 is closed, high-pressure oil supply from the pipe 75 is prevented, and the inside of the back pressure chamber 72A is set to an intermediate pressure, so that the spring is the same as described above. The second vane 52 can be sufficiently urged to the second roller 48 without using a member.

  Furthermore, pressure pulsation can be reduced by the effect of the oil in the back pressure chamber 72A and the intermediate pressure, compared with the case where the high pressure oil in the sealed container 12 is supplied, and the followability of the second vane 52 is further improved. It can be further improved.

(2) Second operation mode (operation at light load)
Next, the controller 210 shifts from the first operation mode to the second operation mode when the room changes from the normal load or the high load state described above to the light load state. The second operation mode is a mode in which only the first rotary compression element 32 substantially performs the compression work, and the electric element 14 is rotated at a low speed in the first operation mode due to a light load in the room. This is an operation mode performed when In the small capacity region of the compression system CS, the refrigerant that compresses by making only the first rotary compression element 32 perform the compression work, compared with the case where the first and second cylinders 38 and 40 perform the compression work. Since the amount of gas can be reduced, it is possible to increase the rotational speed of the electric element 14 even at a light load, improve the operating efficiency of the electric element 14, and reduce the leakage loss of the refrigerant. Because it becomes. Note that at the time of mode switching, the controller 210 rotates the electric element 14 at a low speed, for example, controls the rotation speed to be 40 Hz or less and the compression ratio to be 3.0 or less.

  First, the controller 210 inputs an ON signal to the four-way switching valve 107, and the power of the four-way switching valve 107 is turned on. Thereby, the magnetic field of the solenoid coil 108 is generated, the four-way switching valve 107 is switched, the refrigerant pipe 101 and the pipe 75 are communicated, and the suction side refrigerant of the first rotary compression element 32 flows into the back pressure chamber 72A. Then, the suction side pressure of the first rotary compression element 32 is applied as the back pressure of the second vane 52.

  On the other hand, the controller 210 energizes the stator coil 28 of the electric element 14 via the terminal 20 and the wiring (not shown) as described above, and rotates the rotor 24 of the electric element 14. By this rotation, the first and second rollers 46 and 48 are eccentrically rotated in the first and second cylinders 38 and 40 by being fitted to upper and lower eccentric portions 42 and 44 provided integrally with the rotary shaft 16.

  Thereby, the low-pressure refrigerant flows from the refrigerant pipe 100 of the rotary compressor 10 into the accumulator 146. At this time, since the refrigerant pipe 101 and the pipe 75 are communicated by the four-way switching valve 107 as described above, a part of the refrigerant on the suction side of the first rotary compression element 32 passing through the refrigerant pipe 100 is refrigerant. It flows from the pipe 101 through the pipe 75 into the back pressure chamber 72A. Thereby, the back pressure chamber 72A becomes the suction side pressure of the first rotary compression element 32, and the suction side pressure of the first rotary compression element 32 is applied as the back pressure of the second vane 52. .

  Thus, by applying the suction side pressure of the first rotary compression element 32 as the back pressure of the second vane 52, the refrigerant pressure sucked into the second cylinder 40 and the back of the second vane 52 are Since the pressure becomes the same low pressure, the second vane 52 cannot follow the second roller 48. As a result, the second vane 52 is retracted from the second cylinder 40 and the refrigerant cannot be compressed by the second rotary compression element 34, so that the refrigerant is compressed only by the first rotary compression element 32. become.

  Conventionally, when switching from the first operation mode to the second operation mode, the pressure in the second cylinder 40 and the back pressure chamber 72A of the second vane 52 are the same, so that the second vane 52 becomes unstable and collides with the wall surface of the guide groove 72 of the second cylinder 40, causing a problem of generating a collision sound.

  However, when oil is supplied to the back pressure chamber 72A in the first operation mode as in the present invention, the oil remains in the back pressure chamber 72A immediately after switching from the first operation mode to the second operation mode. As a result, the oil acts like a cushioning material, and the collision noise can be reduced.

  The oil (high pressure) supplied to the back pressure chamber 72A in the first operation mode gradually flows out of the back pressure chamber 72A due to the pressure difference with the suction side refrigerant, and the pipe 75 and the four-way switching valve 107 are discharged. And then into the accumulator 146 together with the low-pressure refrigerant gas in the refrigerant pipe 100, and once stored in the accumulator 146, the oil reservoir 13 in the hermetic container 12 is connected through the communication pipe 148. Returned to

  On the other hand, the low-pressure refrigerant flowing into the accumulator 146 is gas-liquid separated there, and then only the refrigerant gas enters the refrigerant discharge pipe 92 opened in the accumulator 146. The low-pressure refrigerant gas that has entered the refrigerant introduction pipe 92 is sucked into the low-pressure chamber side of the first cylinder 38 of the first rotary compression element 32 through the suction passage 58.

  The refrigerant gas sucked into the low-pressure chamber side of the first cylinder 38 is compressed by the operation of the first roller 46 and the first vane 50 to become a high-temperature and high-pressure refrigerant gas, and the high-pressure chamber side of the first cylinder 38. Then, the liquid is discharged into the discharge silencer chamber 62 through a discharge port (not shown). At this time, in the second operation mode, the discharge silencer chamber 62 functions as an expansion-type silencer chamber, and the discharge silencer chamber 64 functions as a resonance-type silencer chamber. The pressure pulsation of the refrigerant can be further reduced. Thereby, the silencing effect can be further improved in the second operation mode in which the compression work is performed substantially only by the first rotary compression element 32.

  The refrigerant gas discharged into the discharge silencer chamber 62 is discharged into the sealed container 12 through a hole (not shown) that penetrates the cup member 63. Thereafter, the refrigerant in the sealed container 12 is discharged to the outside from a refrigerant discharge pipe 96 formed in the end cap 12B of the sealed container 12, and flows into the outdoor heat exchanger 152. Therefore, the refrigerant gas dissipates heat and is depressurized by the expansion valve 154 and then flows into the indoor heat exchanger 156. The refrigerant evaporates in the indoor heat exchanger 156 and absorbs heat from the air circulated in the room, thereby exerting a cooling action to cool the room. Then, the refrigerant repeats a cycle in which the refrigerant leaves the indoor heat exchanger 156 and is sucked into the rotary compressor 10.

  As described above in detail, according to the present invention, the first and second rotary compression elements 32 and 34 perform the compression work, and the first operation mode in which only the first rotary compression element 32 performs the compression work. The performance and reliability of the compression system CS including the rotary compressor 10 that can be used by switching between the two operation modes can be improved.

  Thus, by configuring the refrigerant circuit of the air conditioner using the compression system CS, it is possible to improve the operation efficiency and performance of the air conditioner and to reduce power consumption.

  In the above embodiment, when the power supply is OFF, the four-way switching valve 107 is in a state where the oil pipe 102 and the pipe 75 are in communication with each other, and the power supply of the four-way switching valve 107 is based on the ON signal from the controller 210. Is turned on, the refrigerant pipe 101 and the pipe 75 are in communication with each other. However, when the power is off, the refrigerant pipe 101 and the pipe 75 are in communication with each other, and based on the ON signal from the controller 210. When the power of the four-way switching valve 107 is turned on, the oil pipe 102 and the pipe 75 may be connected.

  In this case, in the first operation mode, an operation of setting the inside of the back pressure chamber 72A as an intermediate pressure and biasing the second vane 52 to the second roller 48 by the intermediate pressure will be described. After supplying oil into the back pressure chamber 72A as described above (at this time, the power of the four-way switching valve 107 is turned on and the pipe 102 and the pipe 75 are in communication), the controller 210 controls the solenoid valve 105 (see FIG. 2). (Indicated by a broken line) is closed to prevent oil from flowing into the back pressure chamber 72A. Next, the controller 210 transmits an OFF signal to the four-way switching valve 107, whereby the power source of the four-way switching valve 107 is turned OFF, the four-way switching valve 107 is switched, and the refrigerant pipe 101 and the pipe 75 are communicated. The At this time, the high-pressure oil remaining in the pipe 75 enters the refrigerant pipe 101 via the four-way switching valve 107 due to the pressure difference, and enters the accumulator 146 together with the low-pressure refrigerant gas in the refrigerant pipe 100 from there. After being temporarily stored in the accumulator 146, it is returned from the communication pipe 148 to the oil reservoir 13 in the sealed container 12.

  In this case, since the solenoid valve 105 is closed, all of the suction side refrigerant flowing through the refrigerant pipe 100 flows into the accumulator 146 as described above without flowing into the back pressure chamber 72A. On the other hand, the back pressure chamber 72A flows from both the high pressure chamber side and the low pressure chamber side in the second cylinder 40 through the gap of the second vane 52. The pressure is an intermediate pressure between the suction side pressure and the discharge side pressure of the rotary compression elements 32 and 34.

  In this way, the solenoid valve 105 is provided in the pipe 75, the solenoid valve 105 is closed, high-pressure oil supply from the pipe 75 is prevented, and the inside of the back pressure chamber 72A is set to an intermediate pressure, so that the spring is the same as described above. The second vane 52 can be sufficiently urged to the second roller 48 without using a member, and pressure pulsation can be reduced by the effect of oil and intermediate pressure in the back pressure chamber 72A. Thus, the followability of the second vane 52 can be further improved.

  In each of the above embodiments, an HFC or HC refrigerant is used as the refrigerant. However, a refrigerant having a large difference in high and low pressures such as carbon dioxide, for example, a combination of carbon dioxide and PAG (polyalkyl glycol) is used as the refrigerant. It does n’t matter what you do. In this case, since the refrigerant compressed by the rotary compression elements 32 and 34 has a very high pressure, the discharge silencer chamber 62 has a shape in which the upper side of the upper support member 54 is covered by the cup member 63 as in the above embodiments. Then, the cup member 63 may be damaged by the high pressure.

  For this reason, the shape of the discharge muffler chamber above the upper support member 54 where the refrigerant compressed by the rotary compression elements 32 and 34 merges is formed on the upper side of the upper support member 54, By constituting by closing with a cover having a thickness, the present invention can be applied even when a refrigerant having a large high-low pressure difference such as carbon dioxide is contained.

  In each of the above-described embodiments, the rotary compressor 16 has been described as a vertical type, but it goes without saying that the present invention can also be applied to the case where a rotary compressor having a horizontal type as the rotary shaft is used.

  Furthermore, although the two-cylinder rotary compressor is used in each of the above-described embodiments, the present invention may be applied to a compression system including a multi-cylinder rotary compressor including three or more rotary compression elements.

It is a vertical side view of the multi-cylinder rotary compressor of the compression system of Example 1 of this invention. It is a vertical side view of the multi-cylinder rotary compressor of FIG. It is a refrigerant circuit diagram of the air conditioner using the compression system of the Example of this invention. It is a figure which shows the flow of the refrigerant | coolant in the 1st operation mode of the multicylinder rotary compressor of FIG. It is a figure which shows the flow of the refrigerant | coolant at the time of 2 cylinder operation | movement of the conventional multi-cylinder rotary compressor.

Explanation of symbols

CS Compression System 10 Rotary Compressor 12 Sealed Container 14 Electric Element 16 Rotating Shaft 18 Rotation Compression Mechanism Unit 20 Terminal 22 Stator 24 Rotor 26 Laminated Body 28 Stator Coil 30 Laminated Body 32 First Rotary Compression Element 34 Second Rotary Compression Element 36 Intermediate partition plate 38 First cylinder 40 Second cylinder 42, 44 Eccentric portion 46 First roller 48 Second roller 50 First vane 52 Second vane 58, 60 Suction passage 62 Discharge silencer chamber 63 Cup member 68 Lower cover 70, 72 Guide groove 70A Storage portion 72A Back pressure chamber 74 Spring 75, 102 Pipe 92, 94 Refrigerant introduction pipe 96 Refrigerant discharge pipe 100, 101 Refrigerant pipe 105 Solenoid valve 107 Four-way switching valve 152 Outdoor heat exchanger 154 Expansion valve 156 Indoor heat exchanger 210 Trolla

Claims (3)

A drive element and first and second rotary compression elements driven by a rotation shaft of the drive element are housed in a sealed container, and the first and second rotary compression elements are arranged as first and second cylinders. A first roller and a second roller which are fitted into an eccentric portion formed on the rotating shaft and rotate eccentrically in the cylinders, and abutting the first and second rollers, and in the cylinders Are composed of first and second vanes that are divided into a low-pressure chamber side and a high-pressure chamber side, respectively, and only the first vane is urged to the first roller by a spring member, thereby Has a multi-cylinder rotary compressor that can be used by switching between a first operation mode in which compression work is performed and a second operation mode in which only the first rotary compression element performs compression work. In the compression system,
In the first operation mode, the oil in the oil reservoir in the sealed container is supplied to the back pressure chamber of the second vane;
In the second operation mode, the suction system applies the suction side pressure of the first rotary compression element to the back pressure chamber of the second vane.   The compression system according to claim 1, wherein the refrigerant compressed by the first and second rotary compression elements is discharged into the sealed container.   A refrigeration apparatus comprising a refrigerant circuit using the compression system according to claim 1 or 2.

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