WO2014083901A1

WO2014083901A1 - Compressor, refrigeration cycle device, and heat pump hot-water supply device

Info

Publication number: WO2014083901A1
Application number: PCT/JP2013/073336
Authority: WO
Inventors: 野本　宗; 謙作畑中; 啓輔高山; 酒井　大輔
Original assignee: 三菱電機株式会社
Priority date: 2012-11-30
Filing date: 2013-08-30
Publication date: 2014-06-05
Also published as: EP2930449B1; EP2930449A4; EP2930449A1; WO2014083674A1

Abstract

The purpose of the present invention is to use a simple configuration and reduce the amount of refrigerator oil that flows out from a first discharge path in a compressor having a first intake path, the first discharge path, a second intake path, and a second discharge path.　This compressor comprises: the first intake path that guides low-pressure refrigerant to a compression element without releasing same to an internal space of a sealed container; the first discharge path that discharges a high-pressure refrigerant compressed by the compression element, to outside the sealed container without releasing same to the internal space of the sealed container; the second intake path that guides the high-pressure refrigerant that has passed through an external heat exchanger to the internal space of the sealed container; the second discharge path that discharges the high-pressure refrigerant in the internal space of the sealed container, to outside the sealed container; and an oil return flow path that guides the refrigerator oil from the first discharge path either to the internal space of the sealed container or into the second intake path. The pressure inside the internal space of the sealed container and inside the second intake path is lower than the pressure inside the first discharge path, as a result of pressure loss in the external heat exchanger, and the refrigerator oil travels inside the oil return flow path as a result of this pressure difference.

Description

Compressor, refrigeration cycle device and heat pump hot water supply device

The present invention relates to a compressor, a refrigeration cycle apparatus, and a heat pump hot water supply apparatus.

Patent Document 1 has a compression element and an electric element in a hermetic container and hermetically seals a suction pipe (first suction passage) that directly leads a low-pressure side refrigerant to the compression element and a high-pressure refrigerant compressed by the compression element. A discharge pipe (first discharge passage) that discharges directly to the outside of the sealed container without releasing it into the container, and a refrigerant reintroduction pipe (first discharge pipe) that is discharged from the discharge pipe and guides the refrigerant after heat exchange back into the sealed container 2) and a refrigerant re-discharge pipe (second discharge passage) for re-introducing the refrigerant into the sealed container and discharging the refrigerant after passing through the electric element to the outside of the sealed container is disclosed. Has been.

Japanese Unexamined Patent Publication No. 2006-132427

Generally, refrigerating machine oil is supplied into a compression chamber of a compression element of a compressor in order to lubricate and seal a sliding portion and reduce friction and gap leakage. Refrigerator oil is lubricating oil for a compressor of a refrigeration cycle apparatus. In the case of the compressor disclosed in Patent Document 1, a large amount of refrigeration oil flows out of the compressor from the first discharge passage together with the compressed high-pressure refrigerant gas. The high-pressure refrigerant gas and the refrigerating machine oil form a gas-liquid two-phase flow and pass through an external heat exchanger. As a result, there is a problem that the performance of the refrigeration cycle is deteriorated because heat transfer in the heat exchanger is hindered by the refrigeration oil or pressure loss increases due to the influence of the refrigeration oil. In addition, since the amount of refrigerating machine oil inside the compressor is reduced, there is a possibility that reliability may be affected.

The present invention has been made to solve the above-described problems. In the compressor having the first suction passage, the first discharge passage, the second suction passage, and the second discharge passage, An object of the present invention is to reduce the amount of refrigerating machine oil flowing out from the discharge passage together with the refrigerant with a simple configuration, and to provide a refrigeration cycle apparatus and a heat pump hot water supply apparatus provided with the compressor.

A compressor according to the present invention includes a hermetic container, a compression element provided in the hermetic container, a first suction passage that guides the sucked low-pressure refrigerant to the compression element without releasing it into the internal space of the hermetic container, A first discharge passage that directly discharges the high-pressure refrigerant compressed by the compression element to the outside of the sealed container without being discharged into the inner space of the sealed container, and provided downstream of the first discharge path and the first discharge path. A second suction passage that guides the high-pressure refrigerant that has passed through the external heat exchanger to the inner space of the sealed container, a second discharge passage that discharges the high-pressure refrigerant in the inner space of the sealed container to the outside of the sealed container, An oil return passage for guiding the refrigeration oil flowing out from the compression element to the first discharge passage into the internal space of the sealed container or the second suction passage, and when the high-pressure refrigerant passes through the external heat exchanger. The first pressure that is the pressure in the first discharge passage due to the pressure loss that occurs. Compared to the pressure, the second high pressure, which is the pressure in the internal space of the sealed container and the second suction passage, is lowered, and the refrigerating machine oil moves in the oil return flow path due to the difference between the first high pressure and the second high pressure. To do.

According to the present invention, in a compressor having a first suction passage, a first discharge passage, a second suction passage, and a second discharge passage, the amount of refrigerating machine oil flowing out together with the refrigerant from the first discharge passage is reduced. It can be reliably reduced with a simple configuration. As a result, it is possible to suppress heat transfer inhibition and an increase in pressure loss in the heat exchanger that exchanges heat with the refrigerant discharged from the first discharge passage, and to suppress a decrease in refrigerating machine oil inside the compressor. It becomes possible.

It is a block diagram which shows the heat pump hot-water supply apparatus provided with the compressor of Embodiment 1 of this invention. It is a block diagram which shows the hot water storage type hot-water supply system provided with the heat pump hot-water supply apparatus shown in FIG. It is sectional drawing which shows the compressor of Embodiment 1 of this invention. It is sectional drawing which shows typically the flow state of refrigerant gas and refrigeration oil. It is sectional drawing which shows the oil return flow path with which the compressor of Embodiment 1 of this invention is provided. It is a cross-sectional view of the inner pipe of the 1st discharge passage with which the compressor of Embodiment 2 of the present invention is provided. It is sectional drawing which shows the oil return flow path with which the compressor of Embodiment 3 of this invention is provided. It is a longitudinal cross-sectional view of the downstream end vicinity of the 2nd suction passage with which the compressor of Embodiment 4 of this invention is provided. It is a transverse cross section near the downstream end of the 2nd suction passage with which the compressor of Embodiment 4 of the present invention is provided. It is a figure which shows the downstream end vicinity of the 2nd suction passage with which the compressor of Embodiment 5 of this invention is provided.

Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted.
Embodiment 1 FIG.
FIG. 1 is a configuration diagram illustrating a heat pump hot water supply apparatus including the compressor according to the first embodiment of the present invention. FIG. 2 is a configuration diagram showing a hot water storage type hot water supply system including the heat pump hot water supply apparatus shown in FIG. 1. As shown in FIG. 1, the heat pump water heater 1 of the present embodiment includes a compressor 3, a first water refrigerant heat exchanger 4 (first heat exchanger), and a second water refrigerant heat exchanger 5 (first 2 heat exchanger), a refrigerant circuit including an expansion valve 6 (expansion means) and an evaporator 7, and a water flow path for circulating hot water through the first water refrigerant heat exchanger 4 and the second water refrigerant heat exchanger 5. And. The evaporator 7 in the present embodiment is an air refrigerant heat exchanger that performs heat exchange between air and refrigerant. The heat pump hot water supply apparatus 1 of the present embodiment further includes a blower 8 that blows air to the evaporator 7 and a high and low pressure heat exchanger 9 that performs heat exchange between the high pressure side refrigerant and the low pressure side refrigerant. The compressor 3, the first water refrigerant heat exchanger 4, the second water refrigerant heat exchanger 5, the expansion valve 6, the evaporator 7 and the high and low pressure heat exchanger 9 are connected via a pipe through which the refrigerant passes, A refrigerant circuit is formed. The heat pump water heater 1 operates the refrigeration cycle by operating the compressor 3 during the heating operation.

As shown in FIG. 2, the heat pump hot water supply apparatus 1 of the present embodiment can be used as a hot water storage type hot water supply system by combining with the tank unit 2. In the tank unit 2, a hot water storage tank 2a for storing hot water and a water pump 2b are installed. The heat pump hot water supply device 1 and the tank unit 2 are connected via a pipe 11 and a pipe 12 through which water flows, and an electric wiring (not shown). One end of the pipe 11 is connected to the water inlet 1 a of the heat pump hot water supply apparatus 1. The other end of the pipe 11 is connected to the lower part of the hot water storage tank 2 a in the tank unit 2. A water pump 2 b is installed in the middle of the pipe 11 in the tank unit 2. One end of the pipe 12 is connected to the hot water outlet 1 b of the heat pump hot water supply apparatus 1. The other end of the pipe 12 is connected to the upper part of the hot water storage tank 2 a in the tank unit 2. Instead of the illustrated configuration, the water pump 2b may be disposed in the heat pump water heater 1.

As shown in FIG. 1, the compressor 3 of the heat pump water heater 1 includes a sealed container 31, a compression element 32 and an electric element 33 provided in the sealed container 31, a first suction passage 34, and a first suction passage 34. The discharge passage 35, the second suction passage 36, and the second discharge passage 37 are provided. The low-pressure refrigerant sucked from the first suction passage 34 flows directly into the compression element 32 without being discharged into the internal space 311 of the sealed container 31. The compression element 32 is driven by the electric element 33 to compress the low-pressure refrigerant into a high-pressure refrigerant. The high-pressure refrigerant compressed by the compression element 32 is discharged directly outside the sealed container 31 through the first discharge passage 35 without being discharged into the internal space 311 of the sealed container 31. The high-pressure refrigerant discharged from the first discharge passage 35 passes through the pipe 10 and reaches the first water refrigerant heat exchanger 4. The high-pressure refrigerant that has passed through the first water-refrigerant heat exchanger 4 passes through the pipe 17 and reaches the second suction passage 36. The second suction passage 36 guides the high-pressure refrigerant to the internal space 311 of the sealed container 31 of the compressor 3. The high-pressure refrigerant that has flowed into the internal space 311 of the hermetic container 31 cools the electric element 33 by passing between the rotor and the stator of the electric element 33 and the like, and then is discharged from the second discharge passage 37 to the outside of the hermetic container 31. Is discharged. The high-pressure refrigerant discharged from the second discharge passage 37 passes through the pipe 18 and reaches the second water refrigerant heat exchanger 5. The high-pressure refrigerant that has passed through the second water-refrigerant heat exchanger 5 passes through the pipe 19 and reaches the expansion valve 6. The high-pressure refrigerant passes through the expansion valve 6 and becomes a low-pressure refrigerant. This low-pressure refrigerant flows into the evaporator 7 through the pipe 20. The low-pressure refrigerant that has passed through the evaporator 7 reaches the first suction passage 34 through the pipe 21 and is sucked into the compressor 3. The high / low pressure heat exchanger 9 exchanges heat between the high-pressure refrigerant passing through the pipe 19 and the low-pressure refrigerant passing through the pipe 21.

The heat pump water heater 1 includes a water flow path 23 connecting the water inlet 1a and the inlet of the second water refrigerant heat exchanger 5, an outlet of the second water refrigerant heat exchanger 5, and the first water refrigerant heat exchanger. 4 is further provided with a water channel 24 that connects the four inlets, and a water channel 26 that connects the outlet of the first water refrigerant heat exchanger 4 and the hot water outlet 1b. During the heating operation, water flowing in from the water inlet 1 a flows into the second water refrigerant heat exchanger 5 through the water flow path 23 and is heated by the heat of the refrigerant in the second water refrigerant heat exchanger 5. Hot water generated by being heated in the second water-refrigerant heat exchanger 5 flows into the first water-refrigerant heat exchanger 4 through the water flow path 24, and in the first water-refrigerant heat exchanger 4. Then, it is further heated by the heat of the refrigerant. Hot water that has been heated further by being further heated in the first water-refrigerant heat exchanger 4 reaches the outlet 1b through the water channel 26, and is sent to the tank unit 2 through the pipe 12.

As the refrigerant, a refrigerant capable of producing high temperature hot water, for example, a refrigerant such as carbon dioxide, R410A, propane, propylene or the like is suitable, but is not particularly limited thereto.

The high-temperature and high-pressure refrigerant gas discharged from the first discharge passage 35 of the compressor 3 decreases in temperature while dissipating heat while passing through the first water-refrigerant heat exchanger 4. Due to the pressure loss that occurs in the first water-refrigerant heat exchanger 4, the pipes 10, 17, etc., the pressure of the high-pressure refrigerant in the second suction passage 36 is higher than the pressure of the high-pressure refrigerant in the first discharge passage 35. A little lower. In the present embodiment, the high-pressure refrigerant whose temperature has decreased while passing through the first water refrigerant heat exchanger 4 is sucked into the sealed container 31 from the second suction passage 36 to cool the electric element 33, thereby The temperature of the element 33 and the surface temperature of the sealed container 31 can be lowered. As a result, the motor efficiency of the electric element 33 can be improved, and the heat dissipation loss from the surface of the sealed container 31 can be reduced. The high-pressure refrigerant gas guided from the second suction passage 36 to the internal space 311 of the sealed container 31 is discharged from the second discharge passage 37 in a high-pressure state after the temperature rises by taking the heat of the electric element 33. . The high-pressure refrigerant discharged from the second discharge passage 37 flows into the second water refrigerant heat exchanger 5 and decreases in temperature while releasing heat while passing through the second water refrigerant heat exchanger 5. The high-pressure refrigerant whose temperature has been lowered passes through the expansion valve 6 after heating the low-pressure refrigerant while passing through the high-low pressure heat exchanger 9. By passing through the expansion valve 6, the high-pressure refrigerant is depressurized to a low-pressure gas-liquid two-phase state. The low-pressure refrigerant that has passed through the expansion valve 6 absorbs heat from the outside air while passing through the evaporator 7 and is evaporated into gas. The low-pressure refrigerant exiting the evaporator 7 is heated by the high-low pressure heat exchanger 9 and then sucked into the compressor 3 from the first suction passage 34.

If the high-pressure side refrigerant pressure is equal to or higher than the critical pressure, the high-pressure refrigerant in the first water refrigerant heat exchanger 4 and the second water refrigerant heat exchanger 5 decreases in temperature without undergoing a gas-liquid phase transition in a supercritical state. To dissipate heat. If the high-pressure side refrigerant pressure is equal to or lower than the critical pressure, the high-pressure refrigerant radiates heat while liquefying. In the present embodiment, it is preferable to set the high-pressure side refrigerant pressure to be equal to or higher than the critical pressure by using carbon dioxide or the like as the refrigerant. When the high-pressure side refrigerant pressure is equal to or higher than the critical pressure, it is possible to reliably prevent the liquefied refrigerant from flowing into the internal space 311 of the sealed container 31 from the second suction passage 36. For this reason, it can prevent reliably that the liquefied refrigerant | coolant adheres to the electric element 33, and the rotational resistance of the electric element 33 can be reduced. Further, since the liquefied refrigerant does not flow into the internal space 311 of the sealed container 31 from the second suction passage 36, there is an advantage that the refrigeration oil is prevented from being diluted by the refrigerant.

As shown in FIG. 2, a water supply pipe 13 is further connected to the lower part of the hot water storage tank 2 a of the tank unit 2. Water supplied from an external water source such as water supply flows through the water supply pipe 13 into the hot water storage tank 2a and is stored. The hot water storage tank 2a is always maintained in a full water state when water flows in from the water supply pipe 13. In the tank unit 2, a hot water supply mixing valve 2c is further provided. The hot water supply mixing valve 2 c is connected to the upper part of the hot water storage tank 2 a through the hot water discharge pipe 14. In addition, a water supply branch pipe 15 branched from the water supply pipe 13 is connected to the hot water supply mixing valve 2c. One end of a hot water supply pipe 16 is further connected to the hot water supply mixing valve 2c. Although not shown, the other end of the hot water supply pipe 16 is connected to a hot water supply terminal such as a faucet, a shower, or a bathtub.

During the heating operation for boiling the water stored in the hot water storage tank 2a, the water stored in the hot water storage tank 2a is sent to the heat pump water heater 1 through the pipe 11 by the water pump 2b. Is heated to hot water. The hot water generated in the heat pump hot water supply apparatus 1 returns to the tank unit 2 through the pipe 12, and flows into the hot water storage tank 2a from the upper part. By such a heating operation, hot water is stored in the hot water storage tank 2a so that the upper side becomes hot water and the lower side becomes low temperature water.

When hot water is supplied from the hot water supply pipe 16 to the hot water supply terminal, hot water in the hot water storage tank 2 a is supplied to the hot water supply mixing valve 2 c through the hot water supply pipe 14, and low temperature water is supplied to the hot water supply pipe through the water supply branch pipe 15. It is supplied to the mixing valve 2c. The hot water and the low temperature water are mixed by the hot water supply mixing valve 2 c and then supplied to the hot water supply terminal through the hot water supply pipe 16. The hot water supply mixing valve 2c has a function of adjusting the mixing ratio of the hot water and the low temperature water so that the hot water temperature set by the user is obtained.

This hot water storage type hot water supply system includes a control unit 50. The control unit 50 is electrically connected to actuators and sensors (not shown) and a user interface device (not shown) included in the heat pump hot water supply device 1 and the tank unit 2, respectively. It functions as a control means for controlling the operation of the system. In FIG. 2, the control unit 50 is installed in the heat pump hot water supply apparatus 1, but the installation location of the control unit 50 is not limited to the heat pump hot water supply apparatus 1. The control unit 50 may be installed in the tank unit 2. Moreover, you may make it the structure which distribute | arranges the control part 50 in the heat pump hot-water supply apparatus 1 and the tank unit 2, and is connected so that communication is mutually possible.

The controller 50 controls the temperature of the hot water supplied from the heat pump hot water supply apparatus 1 to the tank unit 2 (hereinafter referred to as “hot water temperature”) at the target hot water temperature during the heating operation. The target hot water temperature is set to 65 ° C. to 90 ° C., for example. In this embodiment, the control part 50 controls the tapping temperature by adjusting the rotation speed of the water pump 2b. The control unit 50 detects the tapping temperature with a temperature sensor (not shown) provided in the water flow path 26, and increases the rotation speed of the water pump 2b when the tapping temperature detected is higher than the target tapping temperature. If the hot water temperature is lower than the target hot water temperature, the rotational speed of the water pump 2b is corrected. In this way, the control unit 50 can perform control so that the tapping temperature matches the target tapping temperature. However, the temperature of the hot water may be controlled by controlling the temperature of the refrigerant discharged from the first discharge passage 35 of the compressor 3 or the rotational speed of the compressor 3.

FIG. 3 is a cross-sectional view showing the compressor according to the first embodiment of the present invention. Hereinafter, the compressor 3 of the present embodiment will be further described with reference to FIG. As shown in FIG. 3, the sealed container 31 of the compressor 3 of the present embodiment has a substantially cylindrical shape. An accumulator 27 is installed adjacent to the sealed container 31 of the compressor 3. The low-pressure refrigerant passes through the accumulator 27 and is then sucked into the compressor 3 from the first suction passage 34. Note that the accumulator 27 is not shown in FIG. 1 described above.

In the sealed container 31, a compression element 32 is disposed below the electric element 33. The electric element 33 drives the compression element 32 via the rotating shaft 331. The compression element 32 includes a compression chamber 321, a muffler 322, and a frame 323. The low-pressure refrigerant gas sucked from the first suction passage 34 flows into the compression chamber 321 and is compressed in the compression chamber 321 to become high-pressure refrigerant gas. The high-pressure refrigerant gas compressed in the compression chamber 321 is discharged into the muffler 322. The high-pressure refrigerant gas discharged into the muffler 322 passes through the frame 323, passes through the first discharge passage 35, and is discharged out of the sealed container 31. As described above, the high-pressure refrigerant gas discharged from the first discharge passage 35 passes through the path passing through the first water-refrigerant heat exchanger 4, and passes through the second suction passage 36 to the internal space 311 of the sealed container 31. Inhaled. The internal space 311 of the sealed container 31 becomes a high-pressure atmosphere filled with the high-pressure refrigerant gas flowing from the second suction passage 36. However, as described above, the pressure in the internal space 311 of the sealed container 31, that is, the pressure in the second suction passage 36 is due to pressure loss generated in the first water refrigerant heat exchanger 4, the pipes 10 and 17, and the like. The pressure in the muffler 322, that is, the pressure in the first discharge passage 35 is slightly lower.

In the following description, the pressure in the muffler 322 and the first discharge passage 35 is referred to as a first high pressure, and the pressure in the internal space 311 of the sealed container 31 and the second suction passage 36 is referred to as a second high pressure. The pressure difference between the first high pressure and the second high pressure has a magnitude corresponding to the pressure loss that occurs when the high-pressure refrigerant passes through the first water-refrigerant heat exchanger 4 or the like.

The first suction passage 34, the first discharge passage 35, and the second suction passage 36 each protrude from the side surface of the sealed container 31. The second suction passage 36 is disposed above the first discharge passage 35. The outlet of the second suction passage 36 opens into a space below the electric element 33 in the internal space 311 of the sealed container 31. That is, the outlet of the second suction passage 36 is at a position lower than the electric element 33. An oil reservoir 312 in which refrigeration oil (not shown) is stored is located below the internal space 311 of the sealed container 31. The oil level of the refrigerating machine oil in the oil reservoir 312 in the sealed container 31 is lower than the opening at the outlet of the second suction passage 36. The inlet of the second discharge passage 37 opens into a space above the electric element 33 in the internal space 311 of the sealed container 31. Thus, the outlet of the second suction passage 36 and the inlet of the second discharge passage 37 are located on the opposite sides via the electric element 33.

The high-pressure refrigerant gas that has flowed from the second suction passage 36 into the space below the electric element 33 in the internal space 311 of the sealed container 31 passes through a gap such as between the rotor and the stator of the electric element 33. It passes through and moves to the space above the electric element 33 in the internal space 311. Thereafter, the high-pressure refrigerant gas is discharged out of the sealed container 31 through the second discharge passage 37. As described above, the refrigerant discharged from the second discharge passage 37 passes through the second water refrigerant heat exchanger 5, the expansion valve 6, the evaporator 7, and the like, and then passes through the second passage of the compressor 3. Return to the first suction passage 34.

Refrigerator oil is supplied from the oil reservoir 312 into the compression chamber 321 in order to lubricate and seal the sliding portion of the compression element 32 and reduce friction and gap leakage. The refrigerating machine oil supplied into the compression chamber 321 flows out to the first discharge passage 35 through the muffler 322 and the frame 323 together with the compressed high-pressure refrigerant gas. This high-pressure refrigerant gas and refrigerating machine oil become a gas-liquid two-phase flow.

FIG. 4 is a cross-sectional view schematically showing the flow state of the refrigerant gas and the refrigerating machine oil. As shown in FIG. 4, the flow state of the refrigerant gas and the refrigerating machine oil is a state called an annular flow or an annular spray flow. That is, the refrigerating machine oil that is in the liquid phase flows as an annular liquid film along the tube wall, and the refrigerant gas that is in the gas phase flows in the center of the tube. Such a state is called an annular flow. Moreover, in the refrigerant gas at the center of the pipe, a part of the refrigerating machine oil may be scattered to form a spray. Such a state is called an annular spray flow.

When a large amount of refrigeration oil that has flowed out of the compression element 32 into the first discharge passage 35 together with the high-pressure refrigerant gas flows into the first water refrigerant heat exchanger 4, the heat transfer in the first water refrigerant heat exchanger 4 is refrigerated. The performance of the heat pump hot water supply apparatus 1 may be deteriorated by being obstructed by machine oil or increasing pressure loss. Further, when the amount of the refrigerating machine oil in the sealed container 31 is reduced, there is a possibility that the reliability may be affected. Therefore, in order to suppress the inflow of the refrigerating machine oil to the first water refrigerant heat exchanger 4, the compressor 3 of the first embodiment uses the refrigerating machine oil that has flowed out from the compression element 32 to the first discharge passage 35. An oil return channel that leads to the internal space 311 of the sealed container 31 is provided. Hereinafter, the oil return flow path provided in the compressor 3 of the present embodiment will be described with reference to FIG.

FIG. 5 is a cross-sectional view showing an oil return flow path provided in the compressor 3 according to the first embodiment of the present invention. As shown in FIG. 5, the first discharge passage 35 has an outer tube 351 and an inner tube 352 disposed inside the outer tube 351. The upstream end of the outer tube 351 is airtightly fitted into a hole provided in the wall of the sealed container 31. The upstream end surface of the outer tube 351 is in contact with the frame 323 of the compression element 32. The inner tube 352 protrudes from the upstream end surface of the outer tube 351 and is inserted into a passage 324 formed in the frame 323. The upstream end of the inner tube 352 is fitted in the passage 324 in an airtight manner. A plurality of holes 353 through which refrigeration oil can pass are formed in the tube wall of the inner tube 352. The hole 353 opens on the inner peripheral surface of the inner pipe 352 of the first discharge passage 35. A gap is formed between the inner peripheral surface of the outer tube 351 and the outer peripheral surface of the inner tube 352. This gap constitutes a first oil return channel 354 through which the refrigeration oil can pass. A sealing member 355 is sealed between the outer peripheral surface of the downstream end of the inner tube 352 and the inner peripheral surface of the outer tube 351. The frame 323 is formed with a second oil return channel 325 through which refrigeration oil can pass. The second oil return channel 325 includes an annular groove that communicates with the first oil return channel 354 and a through channel that passes between the groove and the lower surface of the frame 323. Thus, the hole 353 communicates with the internal space 311 of the sealed container 31 via the first oil return channel 354 and the second oil return channel 325.

The refrigerating machine oil supplied into the compression chamber 321 of the compression element 32 flows into the inner pipe 352 of the first discharge passage 35 through the muffler 322 and the passage 324 in the frame 323 together with the compressed high-pressure refrigerant gas. . Inside the inner pipe 352, the high-pressure refrigerant gas and the refrigerating machine oil form an annular flow. That is, most of the refrigerating machine oil in the inner pipe 352 flows as an annular liquid film along the inner peripheral surface of the inner pipe 352. The refrigerating machine oil that exists as a liquid film on the inner peripheral surface of the inner tube 352 is sucked into the hole 353 that opens on the inner peripheral surface of the inner tube 352 as shown by a thin arrow in FIG. It passes through the return channel 354 and the second oil return channel 325, and flows out from the outlet of the second oil return channel 325 to the internal space 311 of the sealed container 31. Since the refrigerating machine oil has a higher density than the refrigerant gas, the refrigerating machine oil that has flowed out from the outlet of the second oil return channel 325 falls due to gravity and enters the oil reservoir 312 below the inner space 311 of the sealed container 31. Return. On the other hand, the refrigerant gas passes through the inner pipe 352, reaches the outer pipe 351, and is sent to the first water refrigerant heat exchanger 4 side.

As described above, the oil return channel in the first embodiment includes the first oil return channel 354 provided on the outer peripheral side of the inner pipe 352 of the first discharge passage 35, the first oil return channel 354, The second oil return flow path 325 is configured to communicate with the inner space 311 of the sealed container 31 inside the sealed container 31.

According to the first embodiment, by providing the compressor 3 with the oil return channel as described above, the refrigerating machine oil flowing out to the first discharge passage 35 can be guided to the internal space 311 of the sealed container 31. it can. For this reason, the quantity of the refrigerating machine oil which flows into the 1st water-refrigerant heat exchanger 4 from the 1st discharge channel 35 can be reduced reliably. As a result, an increase in pressure loss due to the refrigerating machine oil and heat transfer inhibition in the first water refrigerant heat exchanger 4 can be reliably suppressed. Thereby, the performance of the heat pump hot-water supply apparatus 1 can be improved. Moreover, since it can suppress that the quantity of the refrigeration oil in the airtight container 31 reduces, the reliability of the compressor 3 can be improved. Moreover, since it is not necessary to provide an oil separator in the middle of the piping connecting the compressor 3 and the first water refrigerant heat exchanger 4, the apparatus configuration can be simplified and reduced in size.

In particular, in the first embodiment, the first oil return channel 354 and the second oil return channel 325 can be integrally provided in the first discharge passage 35 or in the vicinity thereof. Therefore, the above effect can be achieved with a very simple and small configuration. For this reason, the manufacturing cost can be reduced, the weight can be reduced, and the space can be saved.

As described above, the second high pressure in the internal space 311 of the sealed container 31 is lower than the first high pressure in the first discharge passage 35. For this reason, the refrigeration oil in the 1st oil return flow path 354 and the 2nd oil return flow path 325 moves automatically by the force which the difference of a 1st high pressure and a 2nd high pressure brings. For this reason, the refrigerating machine oil in the first discharge passage 35 can be returned to the internal space 311 of the sealed container 31 efficiently and reliably. In addition, the difference between the first high pressure and the second high pressure is a magnitude corresponding to the pressure loss generated in the first water refrigerant heat exchanger 4 or the like, so that it is not an excessive pressure difference but an appropriate pressure difference. . For this reason, the force provided to the refrigerating machine oil in the first oil return channel 354 and the second oil return channel 325 due to the difference between the first high pressure and the second high pressure moves the refrigerating machine oil at an appropriate speed. Further, the high-pressure refrigerant gas in the first discharge passage 35 passes through the oil return passage to the internal space 311 of the sealed container 31 without providing an on-off valve, a pressure reducing valve, a capillary tube, or the like in the middle of the oil return passage. It can be surely prevented from leaking. Therefore, it is not necessary to provide an on-off valve, a pressure reducing valve, a capillary tube, etc. in the middle of the oil return channel, and the configuration can be simplified.

In the first embodiment, since the refrigeration oil is sucked into the first oil return channel 354 from the plurality of holes 353 opened in the inner peripheral surface of the inner tube 352 of the first discharge passage 35, the inner tube 352 The refrigerating machine oil forming an annular liquid film along the inner peripheral surface can be efficiently introduced into the first oil return channel 354.

In the first embodiment, the amount of refrigerating machine oil flowing out from the compression element 32 to the first discharge passage 35 is examined in advance, and the size of the holes 353 and the number of the holes 353 are set according to the amount. Thus, the inflow amount of the refrigerating machine oil from the hole 353 to the first oil return channel 354 can be controlled to an appropriate amount.

By the way, the compressor for compressing the refrigerant generally has a low-pressure shell type in which the low-pressure refrigerant gas before compression fills the internal space of the sealed container, and a high-pressure shell in which the high-pressure refrigerant gas after compression fills the internal space of the sealed container. There is an expression. A “shell” is a sealed container. As described above, the compressor 3 according to the first embodiment is a high-pressure shell type because the internal space 311 of the sealed container 31 is filled with the high-pressure refrigerant gas. Of the high-pressure shell type compressors, in a general compressor having one refrigerant suction passage and one refrigerant passage, when the oil separator is provided on the discharge passage side of the compressor, the oil separator It is difficult to return the separated refrigeration oil directly to the internal space of the sealed container. In a general high-pressure shell type compressor, the refrigerant pressure on the discharge passage side is equal to the pressure in the inner space of the closed container (shell), so the refrigerating machine oil separated by the oil separator is separated from the closed container by the pressure difference. This is because it cannot be sent to the internal space. For this reason, when an oil separator is provided on the discharge passage side of a general high-pressure shell compressor, the refrigeration oil separated by the oil separator must be returned to the suction passage side of the low-pressure compressor. I do not get. Therefore, an oil return pipe that connects the oil separator provided on the discharge passage side of the compressor and the suction passage side is required. On the other hand, in the compressor 3 according to the first embodiment, as described above, the refrigerating machine oil is supplied from the first discharge passage 35 to the sealed container 31 using the difference between the first high pressure and the second high pressure. It can be returned directly to the internal space 311. For this reason, there is an advantage that the structure can be extremely simplified.

On the other hand, in a low-pressure shell type compressor, an oil separator is provided on the discharge passage side, and an oil return pipe for connecting the oil separator and the sealed container is provided. It can be sent to the internal space of the sealed container by a pressure difference. However, in this configuration, the pressure of the oil separator is equal to the pressure of the high-pressure refrigerant gas, and the pressure of the internal space of the sealed container is equal to the pressure of the low-pressure refrigerant gas. The difference from the space pressure is too large. For this reason, high-pressure refrigerant gas may flow into the internal space of the sealed container through the oil return pipe. Therefore, when the oil separator is provided on the discharge passage side of the low-pressure shell compressor, the high-pressure refrigerant gas is prevented from leaking from the oil separator through the oil return pipe to the internal space of the sealed container. Therefore, it is necessary to provide an on-off valve, a pressure reducing valve, a capillary tube, etc. in the middle of the oil return pipe. If an on-off valve, a pressure reducing valve, a capillary tube, or the like is provided in the middle of the oil return pipe, there is a problem that the structure becomes complicated. In contrast, in the compressor 3 according to the first embodiment, as described above, there is no need to provide an on-off valve, a pressure reducing valve, a capillary tube, or the like in the middle of the oil return flow path, so that the structure can be extremely simplified. There is.

The embodiment in the case where the heat pump hot water supply apparatus is configured using the compressor of the present invention has been described above. However, the present invention is not limited to the heat pump hot water supply apparatus, and various vapor compressions such as an air conditioner and a cold insulation apparatus are used. The same can be applied to the refrigeration cycle apparatus.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to FIG. 6. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. Is omitted. FIG. 6 is a cross-sectional view of the inner pipe 352 of the first discharge passage 35 provided in the compressor 3 according to Embodiment 2 of the present invention. As shown in FIG. 6, in the second embodiment, a groove 356 is formed along the longitudinal direction on the inner wall of the inner tube 352 of the first discharge passage 35. In the present embodiment, a large number of grooves 356 are formed in parallel, and the grooves 356 are disposed on the inner circumference of the inner tube 352 over the entire circumference. The second embodiment is the same as the first embodiment except that such a groove 356 is formed on the inner wall of the inner tube 352.

In the second embodiment, since the groove 356 is formed on the inner wall of the inner tube 352, the refrigeration oil is more reliably captured on the inner wall of the inner tube 352 by the action of surface tension. For this reason, refrigeration oil can be made to flow more efficiently into the hole 353 formed in the inner pipe 352. Therefore, the refrigeration oil can be more reliably separated from the high-pressure refrigerant gas in the first discharge passage 35 and returned to the internal space 311 of the sealed container 31.

In the example shown in FIG. 6, the cross-sectional shape of the groove 356 is substantially V-shaped. In addition, the cross-sectional shape of the groove 356 may be a rectangular shape, a semicircular shape, or the like. Further, the groove 356 may not be completely parallel to the axial direction of the inner tube 352, and the groove 356 may be formed with a twist angle with respect to the axial direction of the inner tube 352.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to FIG. 7. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. Is omitted. FIG. 7 is a cross-sectional view showing an oil return flow path included in the compressor 3 according to Embodiment 3 of the present invention. The third embodiment is the same as the first embodiment except that the configuration of the oil return channel is different. Hereinafter, with reference to FIG. 7, the oil return flow path provided in the compressor 3 of the third embodiment will be described.

As shown in FIG. 7, the first discharge passage 35 includes an outer tube 351 and an inner tube 352 disposed inside the outer tube 351. The upstream end of the outer tube 351 is airtightly fitted into a hole provided in the wall of the sealed container 31. The upstream end surface of the outer tube 351 is in contact with the frame 323 of the compression element 32. The inner tube 352 protrudes from the upstream end surface of the outer tube 351 and is inserted into a passage 324 formed in the frame 323. The upstream end of the inner tube 352 is fitted in the passage 324 in an airtight manner. A plurality of holes 353 through which refrigeration oil can pass are formed in the side wall of the inner pipe 352. The hole 353 opens on the inner peripheral surface of the inner pipe 352 of the first discharge passage 35. A gap is formed between the inner peripheral surface of the outer tube 351 and the outer peripheral surface of the inner tube 352. This gap constitutes a first oil return channel 354 through which the refrigeration oil can pass. A sealing member 355 is sealed between the outer peripheral surface of the downstream end of the inner tube 352 and the inner peripheral surface of the outer tube 351. The first oil return channel 354 communicates with the second suction passage 36 via the second oil return channel 357. In the illustrated configuration, a hole formed in the tube wall of the outer tube 351 outside the first oil return channel 354 and a hole formed in the tube wall of the second suction passage 36 are connected by a tube. The second oil return channel 357 is constituted by this pipe. In this way, the hole 353 communicates with the inside of the second suction passage 36 via the first oil return channel 354 and the second oil return channel 357.

The refrigerating machine oil supplied into the compression chamber 321 of the compression element 32 flows into the inner pipe 352 of the first discharge passage 35 through the muffler 322 and the passage 324 in the frame 323 together with the compressed high-pressure refrigerant gas. Form an annular flow. The refrigerating machine oil that exists as a liquid film on the inner peripheral surface of the inner pipe 352 is sucked into the hole 353 that opens on the inner peripheral surface of the inner pipe 352 as shown by a thin arrow in FIG. 354 and the second oil return flow path 357 reach the second suction passage 36. The refrigerating machine oil further flows out from the outlet of the second suction passage 36 into the internal space 311 of the sealed container 31, falls due to gravity, and returns to the oil reservoir 312 below the internal space 311 of the sealed container 31. On the other hand, the high-pressure refrigerant gas in the inner pipe 352 passes through the inner pipe 352, reaches the outer pipe 351, and is sent to the first water refrigerant heat exchanger 4.

Thus, the oil return flow path in the third embodiment includes the first oil return flow path 354 provided on the outer peripheral side of the inner pipe 352 of the first discharge passage 35, the first oil return flow path 354, A second oil return passage 357 is provided that communicates with the second suction passage 36 outside the sealed container 31.

In the compressor 3 according to the third embodiment, the oil return flow path as described above is provided in the compressor 3 so that the refrigeration oil flowing out to the first discharge passage 35 is guided to the second suction passage 36. This refrigerating machine oil can be returned from the second suction passage 36 to the internal space 311 of the sealed container 31. For this reason, the quantity of the refrigerating machine oil which flows into the 1st water-refrigerant heat exchanger 4 from the 1st discharge channel 35 can be reduced reliably. As a result, an increase in pressure loss due to the refrigerating machine oil and heat transfer inhibition in the first water refrigerant heat exchanger 4 can be reliably suppressed. Thereby, the performance of the heat pump hot-water supply apparatus 1 can be improved. Moreover, since it can suppress that the quantity of the refrigeration oil in the airtight container 31 reduces, the reliability of the compressor 3 can be improved. Moreover, since it is not necessary to provide an oil separator in the middle of the piping connecting the compressor 3 and the first water refrigerant heat exchanger 4, the apparatus configuration can be simplified and reduced in size.

Further, according to the third embodiment, the first oil return channel 354 and the second oil return channel 357 are arranged in the vicinity of the first discharge passage 35 and the second suction passage 36 of the compressor 3. And the structure is simple. For this reason, the manufacturing cost can be reduced, the weight can be reduced, and the space can be saved.

Further, in the present third embodiment, as in the first embodiment, the first oil return flow channel 354 and the second oil return flow are generated by a force having an appropriate magnitude caused by the difference between the first high pressure and the second high pressure. The refrigerating machine oil in the path 357 automatically moves at an appropriate speed. Thereby, the same effect as Embodiment 1 is acquired. In the third embodiment, a groove 356 may be formed on the inner wall of the inner tube 352 as in the second embodiment.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to FIG. 8 and FIG. 9. The difference from the above-described embodiment will be mainly described, and the same parts or corresponding parts will be denoted by the same reference numerals. The description is omitted. FIG. 8 is a longitudinal sectional view of the vicinity of the downstream end of the second suction passage 36 provided in the compressor 3 according to Embodiment 4 of the present invention. FIG. 9 is a cross-sectional view of the vicinity of the downstream end of the second suction passage 36 provided in the compressor 3 according to Embodiment 4 of the present invention.

In the third embodiment described above, the refrigerating machine oil in the first discharge passage 35 is guided into the second suction passage 36 and flows into the sealed container 31 from the outlet of the second suction passage 36. When the refrigeration oil flows out from the outlet of the second suction passage 36, the refrigeration oil may be wound up by the flow of the high-pressure refrigerant gas ejected from the outlet of the second suction passage 36. A part of the rolled up refrigerating machine oil is atomized and mixed in the high-pressure refrigerant gas. For this reason, the refrigerating machine oil mixed in the high-pressure refrigerant gas flows out from the second discharge passage 37 and circulates in the refrigerant circuit such as the second water refrigerant heat exchanger 5. As a result, the heat transfer in the second water-refrigerant heat exchanger 5 may be impeded by the refrigerating machine oil, or the pressure loss may increase, so that the performance of the heat pump water heater 1 may deteriorate.

In view of the above matters, in addition to the configuration of the third embodiment, the compressor 3 of the fourth embodiment includes an oil separation means for separating the high-pressure refrigerant gas flowing from the second suction passage 36 and the refrigerating machine oil. Is further provided. Hereinafter, the structure of the oil separation means in the fourth embodiment will be described.

As shown in FIG. 8, the compressor 3 of the fourth embodiment includes an inner pipe 38 inside the second suction passage 36. The high-pressure refrigerant gas can pass through the inner pipe 38. That is, the inner pipe 38 has a flow path cross-sectional area through which the high-pressure refrigerant gas can smoothly pass. On the other hand, the refrigerating machine oil introduced from the first discharge passage 35 into the second suction passage 36 can pass between the inner wall of the second suction passage 36 and the outer wall of the inner pipe 38. . That is, a gap is formed between the inner wall of the second suction passage 36 and the outer wall of the inner tube 38 so as to have a flow path cross-sectional area through which the refrigerating machine oil can smoothly pass.

The downstream end of the inner pipe 38 protrudes from the downstream end of the second suction passage 36. That is, the position of the downstream end of the inner pipe 38 is a position protruding toward the inside of the sealed container 31 as compared with the position of the downstream end of the second suction passage 36. In the fourth embodiment, such an inner pipe 38 is provided as oil separation means. The refrigerating machine oil flows out from the downstream end of the second suction passage 36 and falls downward to the oil reservoir 312 in the lower part of the internal space 311 of the sealed container 31. The high-pressure refrigerant gas is ejected from the downstream end of the inner pipe 38 to the internal space 311 of the sealed container 31. For this reason, since the refrigeration oil flowing out from the downstream end of the second suction passage 36 does not collide with the flow of high-pressure refrigerant gas ejected from the downstream end of the inner pipe 38, the refrigeration oil is wound up by the flow of high-pressure refrigerant gas. Can be reliably prevented from being scattered. In the fourth embodiment, the refrigeration oil flowing out from the downstream end of the second suction passage 36 is reliably dropped and separated in the oil reservoir 312 below the inner space 311 of the sealed container 31 in this way. Can do. For this reason, mixing of the high-pressure refrigerant gas flowing into the internal space 311 of the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be reliably suppressed, and the high-pressure refrigerant gas and the refrigerating machine oil can be reliably separated. . As a result, the amount of refrigerating machine oil flowing out from the second discharge passage 37 mixed with the refrigerant can be reduced. Therefore, the circulation rate of the refrigerating machine oil to the second water refrigerant heat exchanger 5, the expansion valve 6, the evaporator 7 and the like can be reduced, and the increase in pressure loss due to the refrigerating machine oil and the second water refrigerant heat exchanger The heat transfer inhibition at 5 can be reliably suppressed. Thereby, the performance of the heat pump hot water supply apparatus 1 can be further improved. Moreover, it can suppress more reliably that the quantity of the refrigerating machine oil in the airtight container 31 reduces, and the reliability of the compressor 3 can further be improved.

In the fourth embodiment, as shown in FIG. 9, a groove 364 along the longitudinal direction is formed on the inner wall of the second suction passage 36 so that the refrigerator oil can pass through the groove 364. ing. In the fourth embodiment, a large number of grooves 364 are formed in parallel, and the grooves 364 are arranged on the entire inner periphery of the second suction passage 36. In the configuration shown in the drawing, the cross-sectional shape of the groove 364 is substantially V-shaped, but the cross-sectional shape of the groove 364 may be rectangular, semicircular, or the like. Further, the groove 364 may not be completely parallel to the axial direction of the second suction passage 36, and the groove 364 may be formed with a twist angle with respect to the axial direction of the second suction passage 36. Good. In the fourth embodiment, since such a groove 364 is formed on the inner wall of the second suction passage 36, the refrigeration oil flowing in the second suction passage 36 is reliably captured by the groove 364 by the surface tension. The For this reason, the refrigerating machine oil is reliably prevented from being scattered and atomized in the high-pressure refrigerant gas at the center of the second suction passage 36, and the inner wall of the second suction passage 36 and the outer wall of the inner pipe 38 are Refrigerating machine oil can be more reliably guided to the gap. Thereby, mixing of the high-pressure refrigerant gas flowing into the internal space 311 of the sealed container 31 from the second suction passage 36 and the refrigerating machine oil is more reliably suppressed, and the high-pressure refrigerant gas and the refrigerating machine oil are more reliably separated. Can do. However, in the fourth embodiment, the groove 364 on the inner wall of the second suction passage 36 may be omitted. That is, the inner wall of the second suction passage 36 may be smooth. In the fourth embodiment, it is only necessary to provide a gap through which the refrigerating machine oil can pass between the inner wall of the second suction passage 36 and the outer wall of the inner pipe 38.

Embodiment 5 FIG.
Next, a fifth embodiment of the present invention will be described with reference to FIG. 10. The description will focus on the differences from the third and fourth embodiments described above, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted. FIG. 10 is a view showing the vicinity of the downstream end of the second suction passage 36 provided in the compressor 3 according to the fifth embodiment of the present invention.

For the same reason as in the fourth embodiment, the compressor 3 in the fifth embodiment separates the high-pressure refrigerant gas flowing from the second suction passage 36 from the refrigerating machine oil in addition to the configuration of the third embodiment. Oil separation means is further provided. Hereinafter, the configuration of the oil separation means in the fifth embodiment will be described.

As shown in FIG. 10, in the compressor 3 of the fifth embodiment, a cylindrical mesh member 39 is connected to the downstream end of the second suction passage 36 in the sealed container 31. The mesh member 39 is made of, for example, a metal material and has substantially the same diameter as the second suction passage 36. In the fifth embodiment, such a net member 39 is provided as an oil separating means. The central axis of the mesh member 39 is substantially horizontal. The refrigerating machine oil that has flowed out from the downstream end of the second suction passage 36 is captured by the mesh member 39, travels along the circumferential surface of the mesh member 39, gathers at the lower portion of the mesh member 39, and is located below the inner space 311 of the sealed container 31. It falls to the oil sump 312. Further, the end face of the mesh member 39 is open. The high-pressure refrigerant gas is jetted into the internal space 311 of the sealed container 31 not through the mesh (pores) of the mesh member 39 but through the opening at the end face of the mesh member 39. With such a configuration, in the fifth embodiment, it is possible to reliably prevent the refrigeration oil flowing out from the downstream end of the second suction passage 36 from being wound up and scattered by the flow of the high-pressure refrigerant gas. For this reason, mixing of the high-pressure refrigerant gas flowing into the internal space 311 of the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be reliably suppressed, and the high-pressure refrigerant gas and the refrigerating machine oil can be reliably separated. . For this reason, the effect similar to Embodiment 4 is acquired.

In the fifth embodiment, it is desirable that a groove 364 similar to that in the fourth embodiment is formed on the inner wall of the second suction passage 36. Thereby, the refrigerating machine oil flowing in the second suction passage 36 is reliably captured in the groove 364 by the surface tension. For this reason, it is possible to reliably prevent the refrigerating machine oil from being scattered and atomized in the high-pressure refrigerant gas at the center of the second suction passage 36, and to reliably lead the refrigerating machine oil to the mesh member 39 as a liquid film. . Thereby, mixing of the high-pressure refrigerant gas flowing into the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be more reliably suppressed, and both can be more reliably separated.

1 Heat pump water heater, 1a water inlet, 1b hot water outlet, 2 tank unit, 2a hot water storage tank, 2b water pump, 2c hot water mixing valve, 3 compressor, 4 first water refrigerant heat exchanger, 5 second water Refrigerant heat exchanger, 6 expansion valve, 7 evaporator, 8 blower, 9 high / low pressure heat exchanger, 10, 11, 12 pipe, 13 water supply pipe, 14 hot water supply pipe, 15 water supply branch pipe, 16 hot water supply pipe, 17, 18 , 19, 20, 21 pipe, 23, 24, 26 water flow path, 27 accumulator, 31 sealed container, 32 compression element, 33 electric element, 34 first suction passage, 35 first discharge passage, 36 second suction Passage, 37 second discharge passage, 38 inner pipe, 39 mesh member, 50 control unit, 311 internal space, 312 oil reservoir, 321 compression chamber, 322 muffler, 323 Frame, 324 passage, 325 second oil return flow path, 331 rotating shaft, 351 outer pipe, 352 inner pipe, 353 hole, 354 first oil return flow path, 355 sealing member, 356 groove, 357 second oil return flow Road, 364 groove

Claims

A sealed container;
A compression element provided in the sealed container;
A first suction passage that guides the suctioned low-pressure refrigerant to the compression element without releasing it into the internal space of the sealed container;
A first discharge passage for discharging the high-pressure refrigerant compressed by the compression element directly to the outside of the sealed container without discharging into the inner space of the sealed container;
A second suction passage that guides the high-pressure refrigerant that has passed through the first discharge passage and an external heat exchanger provided downstream of the first discharge passage to the internal space of the sealed container;
A second discharge passage for discharging the high-pressure refrigerant in the inner space of the sealed container to the outside of the sealed container;
An oil return passage that guides refrigeration oil that has flowed out of the compression element into the first discharge passage into the internal space of the sealed container or the second suction passage;
With
Due to the pressure loss that occurs when the high-pressure refrigerant passes through the external heat exchanger, the internal space of the sealed container and the second suction are compared with the first high-pressure that is the pressure in the first discharge passage. The second high pressure, which is the pressure in the passage, becomes lower,
A compressor in which the refrigerating machine oil moves in the oil return channel due to a difference between the first high pressure and the second high pressure.
The compressor according to claim 1, wherein the compressor has a plurality of holes opened on an inner peripheral surface of the first discharge passage, and the refrigerating machine oil in the first discharge passage is sucked into the plurality of holes.
The oil return flow path includes a first oil return flow path provided on an outer peripheral side of the first discharge passage, the first oil return flow path, and an internal space of the sealed container inside the sealed container. The compressor according to claim 1, further comprising a second oil return channel that communicates with each other.
The oil return flow path includes a first oil return flow path provided on an outer peripheral side of the first discharge passage, the first oil return flow path, and the second suction passage outside the sealed container. The compressor according to claim 1, further comprising a second oil return channel that communicates with each other.
The compressor according to any one of claims 1 to 4, wherein a groove along a longitudinal direction is formed on an inner wall of the first discharge passage.
The compressor according to any one of claims 1 to 5, further comprising oil separation means for separating the high-pressure refrigerant flowing from the second suction passage into the internal space of the sealed container and the refrigerating machine oil.
An inner pipe provided inside the second suction passage is provided as the oil separating means,
A downstream end of the inner pipe protrudes from a downstream end of the second suction passage;
The high-pressure refrigerant can pass through the inner pipe,
The compressor according to claim 6, wherein the refrigerating machine oil can pass between an inner wall of the second suction passage and an outer wall of the inner pipe.
The compressor according to claim 6, comprising a cylindrical mesh member connected to the downstream end of the second suction passage as the oil separating means.
The compressor according to any one of claims 1 to 8, wherein a pressure on a high pressure side of the refrigerant exceeds a critical pressure.
A compressor according to any one of claims 1 to 9,
A first heat exchanger as the external heat exchanger that radiates heat from the high-pressure refrigerant discharged from the first discharge passage of the compressor;
A second heat exchanger that radiates heat from the high-pressure refrigerant discharged from the second discharge passage of the compressor;
A refrigeration cycle apparatus comprising:
A compressor according to any one of claims 1 to 9,
A first water refrigerant heat exchanger as the external heat exchanger that exchanges heat between the high-pressure refrigerant discharged from the first discharge passage of the compressor and water;
A second water refrigerant heat exchanger for exchanging heat between the high-pressure refrigerant discharged from the second discharge passage of the compressor and water;
A heat pump hot water supply device comprising: