WO2014083674A1

WO2014083674A1 - Compressor, refrigeration cycle device, and heat pump hot-water supply device

Info

Publication number: WO2014083674A1
Application number: PCT/JP2012/081031
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: 2012-11-30
Publication date: 2014-06-05
Also published as: EP2930449A1; WO2014083901A1; EP2930449B1; EP2930449A4

Abstract

The purpose of the present invention is to provide: a compressor capable of reducing the amount of refrigerator oil that flows from a first discharge path; a refrigeration cycle device comprising said compressor; and a heat pump hot-water supply device. This compressor comprises: a sealed container; a first intake path that takes in refrigerant; a compression element provided inside the sealed container and which compresses refrigerant taken in from the first intake path; the first discharge path that discharges refrigerant compressed by the compression element to outside the sealed container; a second intake path that takes into the sealed container refrigerant that has been discharged from the first discharge path and has passed through an external heat exchanger; a second discharge path that discharges to outside the sealed container refrigerant that has been taken inside the sealed container from the second intake path; and an oil return means that guides refrigerator oil that is inside the first discharge path to inside the sealed container.

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

In the conventional compressor described above, refrigeration oil is supplied in the compression chamber of the compression element in order to lubricate and seal the sliding portion and reduce friction and gap leakage. For this reason, a large amount of refrigerating machine oil flows out of the compressor together with the compressed refrigerant gas from the first discharge passage. The refrigerant gas and the refrigerating machine oil form a gas-liquid two-phase flow and flow into an external heat exchanger. As a result, there is a problem that the performance of the refrigeration cycle is lowered due to the heat transfer in the heat exchanger being hindered by the refrigeration oil or the pressure loss being increased 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 in order to solve the above-described problems, and an object thereof is to provide a compressor capable of reducing the amount of refrigerating machine oil flowing out from the first discharge passage. An object of the present invention is to provide a refrigeration cycle apparatus and a heat pump hot water supply apparatus provided with a compressor.

A compressor according to the present invention includes a sealed container, a first suction passage for sucking refrigerant, a compression element that is provided in the sealed container and compresses the refrigerant sucked from the first suction passage, and a compression element. A first discharge passage for discharging the compressed refrigerant to the outside of the sealed container; a second suction passage for discharging the refrigerant discharged from the first discharge passage and passing through the external heat exchanger into the sealed container; A second discharge passage for discharging the refrigerant sucked into the sealed container from the second suction passage to the outside of the sealed container; and an oil return means for guiding the refrigeration oil in the first discharge passage into the sealed container. .

According to the present invention, the amount of refrigerating machine oil flowing out from the first discharge passage can be reduced. 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.

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. FIG. 3 is a cross-sectional view showing the compressor according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view schematically showing the flow state of the refrigerant gas and the refrigerating machine oil. FIG. 5 is a cross-sectional view of the oil return means provided in the compressor according to Embodiment 1 of the present invention. FIG. 6 is a cross-sectional view of the inner pipe of the first discharge passage provided in the compressor according to the second embodiment of the present invention. FIG. 7 is a cross-sectional view of the oil return means provided in the compressor according to Embodiment 3 of the present invention. FIG. 8 is a longitudinal sectional view of the vicinity of the downstream end of the second suction passage provided in the compressor according to the fourth embodiment of the present invention. FIG. 9 is a cross-sectional view of the vicinity of the downstream end of the second suction passage provided in the compressor according to the fourth embodiment of the present invention. FIG. 10 is a view showing the vicinity of the downstream end of the second suction passage provided in the compressor according to the fifth embodiment of the present invention.

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 refrigerant sucked from the first suction passage 34 flows into the compression element 32. The compression element 32 is driven by the electric element 33 and compresses the refrigerant. The refrigerant compressed by the compression element 32 is discharged out of the sealed container 31 through the first discharge passage 35. The refrigerant discharged from the first discharge passage 35 passes through the pipe 10 and reaches the first water refrigerant heat exchanger 4. The 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 refrigerant flowing into the sealed container 31 of the compressor 3 from the second suction passage 36 cools the electric element 33 by passing between the rotor and the stator of the electric element 33 and then the second discharge. It is discharged out of the sealed container 31 from the passage 37. The refrigerant discharged from the second discharge passage 37 passes through the pipe 18 and reaches the second water refrigerant heat exchanger 5. The refrigerant that has passed through the second water refrigerant heat exchanger 5 passes through the pipe 19 and reaches the expansion valve 6. The refrigerant that has passed through the expansion valve 6 flows into the evaporator 7 through the pipe 20. The 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. In the present embodiment, the refrigerant whose temperature has decreased while passing through the first water-refrigerant heat exchanger 4 is drawn into the sealed container 31 from the second suction passage 36 and cools the electric element 33, whereby the electric element The temperature of 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 refrigerant gas sucked into the sealed container 31 rises in temperature by taking the heat of the electric element 33, is then discharged from the second discharge passage 37 and flows into the second water refrigerant heat exchanger 5. While passing through the water / refrigerant heat exchanger 5, the temperature decreases while releasing heat. 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 refrigerant is decompressed to a low-pressure gas-liquid two-phase state. The 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 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 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, the liquefied refrigerant can be reliably prevented from flowing into 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 sealed container 31 from the second suction passage 36, there is an advantage that the refrigerating machine 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 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 refrigerant gas sucked from the first suction passage 34 flows into the compression chamber 321 and is compressed. The refrigerant gas compressed in the compression chamber 321 is discharged into the muffler 322. The refrigerant gas discharged into the muffler 322 passes through the frame 323 and is discharged out of the sealed container 31 through the first discharge passage 35. As described above, the refrigerant gas discharged from the first discharge passage 35 passes through the path passing through the first water-refrigerant heat exchanger 4 and is sucked into the sealed container 31 from the second suction passage 36. .

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 second suction passage 36 opens in the space below the electric element 33 in the sealed container 31. Refrigerating machine oil (not shown) is stored in the lower part of the sealed container 31. The oil level of the refrigerating machine oil in the hermetic container 31 is lower than the first discharge passage 35. The second discharge passage 37 opens into the space above the electric element 33 in the sealed container 31.

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

Compressor oil stored in the sealed container 31 is supplied into the compression chamber 321 in order to lubricate and seal the sliding portion and reduce friction and gap leakage. The refrigerating machine oil supplied into the compression chamber 321 is discharged from the first discharge passage 35 together with the compressed refrigerant gas. This refrigerant gas and refrigerating machine oil form 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 refrigerating machine oil discharged together with the refrigerant gas from the first discharge passage 35 flows into the first water refrigerant heat exchanger 4, heat transfer in the first water refrigerant heat exchanger 4 is inhibited by the refrigerating machine oil. Or the pressure loss increases, the performance of the heat pump water heater 1 may be reduced. 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. In order to improve these points, the compressor 3 includes oil return means for guiding the refrigeration oil in the first discharge passage 35 into the sealed container 31. Hereinafter, with reference to FIG. 5, the oil return means with which the compressor 3 of this embodiment is provided is demonstrated.

FIG. 5 is a cross-sectional view of the oil return means provided in the compressor 3 according to Embodiment 1 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 side holes 353 through which refrigerating machine oil can pass are formed in the side wall of the inner pipe 352. The side hole 353 is open to the inner wall and the outer wall of the inner tube 352. 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. In this way, the side hole 353 communicates with the inside 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 refrigerant gas. Inside the inner pipe 352, the 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 surface of the inner pipe 352. The refrigerating machine oil that exists as a liquid film on the inner surface of the inner pipe 352 is sucked from the side hole 353 as shown by a thin arrow in FIG. 5, and the first oil return channel 354 and the second oil return channel are drawn. It passes through 325 and flows out from the outlet of the second oil return channel 325. 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 accumulates in the lower part of the sealed container 31. 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.

According to this embodiment, the oil return means as described above is provided in the compressor 3 so that the refrigeration oil in the first discharge passage 35 can be returned into the sealed container 31. For this reason, the amount of the refrigeration oil flowing from the first discharge passage 35 to the first water refrigerant heat exchanger 4 can be reduced, and an increase in pressure loss due to the refrigeration oil and the first water refrigerant heat exchanger 4 can be reduced. Heat transfer inhibition 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.

Further, according to the present embodiment, the above-described effects can be achieved with an extremely simple configuration that can be provided in the vicinity of the first discharge passage 35 of the compressor 3. For this reason, compared with the structure which isolate | separates the separator for isolate | separating refrigerant gas and refrigerating machine oil from the compressor 3 and installs in the middle of a refrigerant circuit, manufacturing cost reduction and weight reduction And space saving.

As described above, the refrigerant gas discharged from the first discharge passage 35 passes through the pipe 10, the first water refrigerant heat exchanger 4, and the pipe 17 and reaches the second suction passage 36. In the process, pressure loss occurs. For this reason, the pressure in the second suction passage 36 is lower than the pressure in the first discharge passage 35 by the amount of the pressure loss. The pressure in the sealed container 31 is equal to the pressure in the second suction passage 36. Therefore, the pressure in the first discharge passage 35 is higher than the pressure in the sealed container 31. In the present embodiment, due to the pressure difference between the pressure in the first discharge passage 35 and the pressure in the sealed container 31, the refrigerating machine oil in the inner pipe 352 is naturally sucked into the side hole 353 and the first oil return The air is guided into the sealed container 31 through the flow path 354 and the second oil return flow path 325. For this reason, the refrigeration oil in the inner pipe 352 can be returned to the sealed container 31 efficiently and reliably.

In addition, by setting the hole diameter of the side hole 353 according to the amount of the refrigerating machine oil flowing into the inner pipe 352 from the compression chamber 321, only the refrigerating machine oil is sucked into the side hole 353 and the refrigerant gas is not sucked into the side hole 353. Can be. For this reason, it is possible to reliably prevent the refrigerant gas in the inner pipe 352 from leaking into the sealed container 31 through the side hole 353, the first oil return channel 354, and the second oil return channel 325. .

In the above description, 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. However, the present invention is not limited to the heat pump hot water supply apparatus. The same applies to a vapor compression refrigeration cycle apparatus.

Embodiment 2. FIG.
Next, the 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 side hole 353 formed in the inner pipe 352. Therefore, the refrigeration oil can be more reliably separated from the refrigerant gas in the first discharge passage 35 and returned to 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 described with the same reference numerals. Is omitted. FIG. 7 is a cross-sectional view of the oil return means provided 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 means is different. Hereinafter, with reference to FIG. 7, the oil return means with which the compressor 3 of this Embodiment 3 is provided is demonstrated.

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 side holes 353 through which refrigerating machine oil can pass are formed in the side wall of the inner pipe 352. The side hole 353 is open to the inner wall and the outer wall of the inner tube 352. 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 side hole formed in the outer pipe 351 outside the first oil return channel 354 and a side hole formed in the pipe wall of the second suction passage 36 are connected by a pipe. The second oil return channel 357 is configured by this tube. In this way, the side 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 refrigerant gas. An annular flow is formed. The refrigerating machine oil existing as a liquid film on the inner surface of the inner pipe 352 is sucked from the side hole 353 and passes through the first oil return channel 354 and the second oil return channel 357 as shown by thin arrows in FIG. The second suction passage 36, flows out from the outlet of the second suction passage 36, falls due to gravity, and accumulates in the lower portion of the sealed container 31. On the other hand, the 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.

In the compressor 3 according to the third embodiment, the refrigeration oil in the first discharge passage 35 can be returned into the sealed container 31 by the oil return means as described above. For this reason, the amount of the refrigeration oil flowing from the first discharge passage 35 to the first water refrigerant heat exchanger 4 can be reduced, and an increase in pressure loss due to the refrigeration oil and the first water refrigerant heat exchanger 4 can be reduced. Heat transfer inhibition 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.

Further, according to the third embodiment, the above effect can be achieved with an extremely simple configuration that can be provided in the vicinity of the first discharge passage 35 and the second suction passage 36 of the compressor 3. it can. For this reason, compared with the structure which isolate | separates the separator for isolate | separating refrigerant gas and refrigerating machine oil from the compressor 3 and installs in the middle of a refrigerant circuit, manufacturing cost reduction and weight reduction And space saving.

Further, in the third embodiment, as in the first embodiment, the refrigerating machine oil in the inner pipe 352 is naturally discharged due to the pressure difference between the pressure in the first discharge passage 35 and the pressure in the sealed container 31. Then, the air is sucked into the side hole 353 and guided into the sealed container 31 through the first oil return channel 354, the second oil return channel 357, and the outlet of the second suction channel 36. For this reason, the refrigeration oil in the inner pipe 352 can be returned to the sealed container 31 efficiently and reliably. 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, the fourth embodiment of the present invention will be described with reference to FIG. 8 and FIG. 9. The description will focus on the differences from the third embodiment described above, and the same or corresponding parts are 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 refrigerant gas ejected from the outlet of the second suction passage 36. Part of the rolled up refrigerating machine oil is atomized and mixed in the refrigerant gas. While passing through the electric element 33, the mixed refrigerating machine oil is separated from the refrigerant gas, but it is difficult to completely separate the refrigerating machine oil. For this reason, the refrigerating machine oil that has passed through the electric element 33 together with the 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 suppresses the mixing of the refrigerant gas flowing from the second suction passage 36 and the refrigerating machine oil. A mixing suppression means is further provided. Hereinafter, the structure of the mixing suppression 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 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 refrigerant gas can pass smoothly. 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 a mixing suppression means. The refrigerating machine oil flows out from the downstream end of the second suction passage 36 and falls to the lower part in the sealed container 31. The refrigerant gas is jetted into the sealed container 31 from the downstream end of the inner tube 38. 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 the refrigerant gas ejected from the downstream end of the inner pipe 38, the refrigeration oil is wound up by the flow of the refrigerant gas. It is possible to reliably prevent scattering. In the fourth embodiment, the refrigeration oil flowing out from the downstream end of the second suction passage 36 can be reliably dropped and separated into the lower part in the sealed container 31 in this way. For this reason, mixing of the refrigerant gas flowing into the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be suppressed. 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 refrigerant gas in the central portion of the second suction passage 36, and the gap between the inner wall of the second suction passage 36 and the outer wall of the inner pipe 38. The refrigerating machine oil can be guided more reliably. Thereby, mixing of the refrigerant gas flowing into the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be more reliably suppressed. 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, the 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.

In the compressor 3 of the fifth embodiment, for the same reason as in the fourth embodiment, in addition to the configuration of the third embodiment, the refrigerant gas flowing from the second suction passage 36 and the refrigerating machine oil are mixed. Further, a mixing suppression means for suppressing the above is provided. Hereinafter, the configuration of the mixing suppression unit 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 a mixing suppression means. 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 mesh member 39, gathers at the lower portion of the mesh member 39, and falls to the lower portion of the sealed container 31. Thereby, 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 refrigerant gas. For this reason, mixing of the refrigerant gas flowing into the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be suppressed, and the same effect as in the fourth embodiment can be obtained.

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 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 refrigerant gas flowing into the sealed container 31 from the second suction passage 36 and the refrigerating machine oil can be more reliably suppressed.

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 section, 321 compression chamber, 322 muffler, 323 frame, 324 passage, 325 second Oil return passage, 331 rotary shaft, 351 the outer tube, 352 inner pipe 353 side hole 354 first oil return passage 355 sealing member 356 groove, 357 second oil return passage, 364 grooves

Claims

A sealed container;
A first suction passage for sucking refrigerant;
A compression element provided in the hermetic container and compressing the refrigerant sucked from the first suction passage;
A first discharge passage for discharging the refrigerant compressed by the compression element to the outside of the sealed container;
A second suction passage for sucking the refrigerant discharged from the first discharge passage and passing through an external heat exchanger into the sealed container;
A second discharge passage for discharging the refrigerant sucked into the sealed container from the second suction passage to the outside of the sealed container;
Oil return means for guiding the refrigeration oil in the first discharge passage into the sealed container;
A compressor comprising:
The compressor according to claim 1, wherein the oil return means has a side hole opening in an inner wall of the first discharge passage.
The pressure in the first discharge passage is higher than the pressure in the sealed container, and the first discharge passage is caused by a pressure difference between the pressure in the first discharge passage and the pressure in the sealed container. The compressor according to claim 2, wherein the refrigerating machine oil is sucked into the side hole.
The compressor according to claim 2 or 3, wherein a groove along the longitudinal direction is formed in an inner wall of the first discharge passage.
The compressor according to any one of claims 2 to 4, wherein the oil return means includes an oil return flow path that allows the side hole and the inside of the sealed container to communicate with each other.
The compressor according to any one of claims 2 to 4, wherein the oil return means includes an oil return flow path that allows the side hole and the second suction passage to communicate with each other.
The compressor according to claim 6, further comprising a mixing suppression unit that suppresses mixing of refrigerant and refrigerant oil flowing into the sealed container from the second suction passage.
An inner tube provided inside the second suction passage is provided as the mixing suppression means,
A downstream end of the inner pipe protrudes from a downstream end of the second suction passage;
A refrigerant can pass through the inner pipe,
The compressor according to claim 7, wherein 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 7, comprising a cylindrical mesh member connected to a downstream end of the second suction passage as the mixing suppression means.
The compressor includes an electric element for driving the compression element in the sealed container,
The compressor according to any one of claims 1 to 9, wherein the refrigerant introduced into the sealed container from the second suction passage is discharged from the second discharge passage after cooling the electric element. .
The compressor according to any one of claims 1 to 10, wherein a pressure on a high pressure side of the refrigerant is a pressure exceeding a critical pressure.
A compressor according to any one of claims 1 to 11,
A first heat exchanger that dissipates heat from the refrigerant discharged from the first discharge passage of the compressor;
A second heat exchanger that dissipates heat from the 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 11,
A first water-refrigerant heat exchanger that exchanges heat between the refrigerant discharged from the first discharge passage of the compressor and water;
A second water refrigerant heat exchanger that performs heat exchange between the refrigerant discharged from the second discharge passage of the compressor and water;
A heat pump hot water supply device comprising: