JP6631381B2 - Compressor - Google Patents

Description

  The present invention relates to a compressor for compressing a fluid.

  2. Description of the Related Art As an example of this type of compressor, a compressor described in Patent Literature 1, for example, is conventionally known. The compressor of Patent Document 1 is an electric scroll compressor that compresses and discharges a refrigerant, and is mounted on a vehicle for air conditioning in a vehicle compartment, for example. In the compressor of Patent Document 1, a fixed scroll, a revolving scroll that forms a compression chamber between the fixed scroll, and a bearing that rotatably supports a drive shaft that revolves the revolving scroll are fitted. And a bearing member.

  A back pressure chamber is defined between the fixed scroll and the bearing member, and the high pressure refrigerant compressed in the compression chamber is supplied to the back pressure chamber together with the lubricating oil. Therefore, the orbiting scroll is urged toward the fixed scroll by the pressure in the back pressure chamber, and the bearing oil is lubricated by the lubricating oil.

JP 2010-148296 A

  The compressor disclosed in Patent Literature 1 is used, for example, for air-conditioning in a vehicle cabin. As such a compressor for air-conditioning, for example, there is a compressor that operates during both cooling and heating in a vehicle cabin.

  Then, as described above, for example, during the operation of the compressor, a part of the refrigerant compressed by the orbiting scroll is introduced into the back pressure chamber. Thus, during cooling of the vehicle interior, the orbiting scroll is pressed against the fixed scroll by the refrigerant pressure in the back pressure chamber, whereby the airtightness between the orbiting scroll and the fixed scroll is sufficiently ensured, and the compression work is performed. Done. This is because the outside of the vehicle compartment is warm during cooling, and the refrigerant introduced into the back pressure chamber easily becomes high temperature and high pressure.

  That is, at the time of cooling, the refrigerant pressure in the back pressure chamber having a sufficient size for ensuring the airtightness between the orbiting scroll and the fixed scroll is easily ensured. Can be pressed against a fixed scroll. As a result, the compression work of the compressor can be operated with moderate vibration.

  However, in such a structure in which the airtightness between the orbiting scroll and the fixed scroll is secured by the refrigerant pressure in the back pressure chamber, for example, when the outside air temperature is low during the heating operation (for example, the outside air temperature is about -20 ° C to 0 ° C). ), It may not be possible to obtain a refrigerant pressure large enough to ensure the airtightness. Specifically, at the time of starting the heating operation, the compressor sucks the low-temperature refrigerant before pressurization that has stayed outside the vehicle compartment, and in that case, in order to secure the above-mentioned airtightness, the back pressure chamber is required. It may take some time for the refrigerant pressure to reach a sufficient level.

  Therefore, at the time of starting the heating operation, the refrigerant back pressure as the refrigerant pressure in the back pressure chamber that presses the orbiting scroll against the fixed scroll cannot be sufficiently secured, and the gap between the orbiting scroll and the fixed scroll has the refrigerant back pressure. The pressure is expanded according to the shortage, and the pressure of the refrigerant is released from the compression chamber. Further, due to the shortage of the refrigerant back pressure, the orbiting scroll swings with the orbiting of the orbiting scroll, and increases the vibration of the compressor or enlarges the variation of the vibration of the compressor. Such an increase in the vibration of the compressor and an increase in the variation in the vibration may cause an increase in the noise in the vehicle interior or the noise outside the vehicle interior, and may increase the discomfort of the occupant.

  In particular, in the compressor used in the gas injection cycle, when the heating operation is started, the refrigerant before the pressure rise merges with the refrigerant in the middle of the compression in the compression chamber.

  In view of the above, the present invention provides a compressor capable of appropriately securing a pressing force for pressing an orbiting scroll against a fixed scroll when a refrigerant back pressure that is a pressure in a back pressure chamber is insufficient. Aim.

In order to achieve the above object, a compressor according to the first aspect of the present invention includes:
A fixed scroll (401) as a non-rotating member;
A compression chamber (40a) is formed between the fixed scroll and the fixed scroll, and the volume of the compression chamber is changed by turning the fixed scroll around a predetermined axis (CLm). An orbiting scroll (402) for compressing the fluid in the room;
A back pressure chamber forming part (403) in which a back pressure chamber (403a) into which a part of the fluid compressed in the compression chamber is introduced;
A pressing device (60, 62) for generating a pressing force (Fp) for pressing the orbiting scroll against the fixed scroll in an axial direction (DRm) of a predetermined axis.
The back pressure chamber causes the pressure of the fluid in the back pressure chamber to act as a back pressure that presses the orbiting scroll against the fixed scroll in the axial direction,
The pressing device increases the pressing force as the temperature of the fluid in the back pressure chamber is lower ,
The pressing device is composed of a bimetal washer in which a low expansion layer (601, 621) and a high expansion layer (602, 622) having a larger linear expansion coefficient than the low expansion layer are laminated in the axial direction. Located at a location where the temperature of the fluid in the pressure chamber can be sensed directly or indirectly,
The bimetal washer increases the pressing force as the temperature of the bimetal washer decreases, due to the difference between the linear expansion coefficient of the low expansion layer and the linear expansion coefficient of the high expansion layer .

  Here, since the fluid in the back pressure chamber is a fluid compressed in the compression chamber, it is a compressible fluid, that is, a gas-liquid two-phase or gas-phase fluid. Therefore, in a compressor, the lower the temperature of the fluid, the lower the pressure of the fluid.

  According to the invention, the pressing device generates a pressing force for pressing the orbiting scroll against the fixed scroll in the axial direction. Further, the pressing device increases the pressing force as the temperature of the fluid in the back pressure chamber is lower. Therefore, the lower the pressure in the back pressure chamber according to the temperature of the fluid in the back pressure chamber, the greater the pressing force generated by the pressing device. Accordingly, it is possible to appropriately secure the pressing force when the pressure in the back pressure chamber is insufficient.

  Each symbol in the claims and parentheses described in this section is an example showing a correspondence relationship with specific contents described in the embodiment described later.

FIG. 1 is a diagram schematically illustrating an overall configuration of a vehicle air conditioner in a first embodiment. FIG. 2 is a longitudinal sectional view of the compressor showing an internal structure of the compressor that forms a part of the heat pump cycle in the first embodiment. FIG. 3 is an enlarged detail view of a portion III in FIG. 2. It is sectional drawing which showed the spring member contained in the compressor of 1st Embodiment by itself, and was the figure which showed the shape when the temperature of the spring member was set to the temperature at the time of steady operation of a compressor. . It is sectional drawing which showed the spring member contained in the compressor of 1st Embodiment as a single body, and the shape when the temperature of the spring member is a temperature significantly lower than the temperature at the time of steady operation of a compressor. FIG. 5 is a time chart showing transitions of a discharge refrigerant pressure, a suction refrigerant pressure, a discharge refrigerant temperature, and a suction refrigerant temperature of the compressor when the vehicle air conditioner of the first embodiment is operated in a heating operation mode. It is a longitudinal section of a compressor showing an internal structure of a compressor in a 2nd embodiment, and is a figure corresponding to Drawing 2 of a 1st embodiment. FIG. 8 is an enlarged detailed view of a portion VIII of FIG. 7 and is a diagram corresponding to FIG. 3 of the first embodiment. FIG. 10 is a cross-sectional view illustrating the shape of a single unit of the second spring member when the temperature of the second spring member is equal to the temperature at the time of steady operation of the compressor in the second embodiment, FIG. 4 is a diagram corresponding to FIG. FIG. 9 is a cross-sectional view illustrating the shape of the second spring member alone when the temperature of the second spring member is significantly lower than the temperature during steady operation of the compressor in the second embodiment; FIG. 6 is a diagram corresponding to FIG. 5 of the first embodiment.

  Hereinafter, embodiments for implementing the present invention will be described with reference to the drawings. In the following embodiments, portions that are the same or equivalent are denoted by the same reference numerals in the drawings.

(1st Embodiment)
FIG. 1 is a diagram schematically illustrating an overall configuration of a vehicle air conditioner 1 in the present embodiment. The vehicle air conditioner 1 is mounted on a vehicle such as a hybrid vehicle, a plug-in hybrid vehicle, or an electric vehicle.

  As shown in FIG. 1, the vehicle air conditioner 1 includes a heat pump cycle 10, an indoor air conditioning unit 30, an air conditioning control device (not shown), and the like. In the vehicle air conditioner 1, the heat pump cycle 10 has a function of cooling or heating the air blown into the vehicle compartment, which is blown into the vehicle compartment, which is a space to be air-conditioned.

  The heat pump cycle 10 is configured to be switchable to a plurality of refrigerant circuits, such as a refrigerant circuit in a cooling operation mode for cooling the vehicle interior and a refrigerant circuit in a heating operation mode for heating the interior of the vehicle. 1 indicates a refrigerant flow in the cooling operation mode in the heat pump cycle 10, and a broken arrow FL2 indicates a refrigerant flow in the heating operation mode.

  Further, in the heat pump cycle 10, an HFC-based refrigerant (specifically, R134a) is employed as the refrigerant to constitute a vapor compression subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant. I have. Of course, an HFO-based refrigerant (for example, R1234yf) or the like may be employed. Refrigeration oil for lubricating the compressor 11 is mixed in the refrigerant, and a part of the refrigeration oil circulates in the cycle together with the refrigerant.

  As shown in FIG. 1, a heat pump cycle 10 includes a compressor 11, an indoor condenser 12, a high-stage expansion valve 13, a gas-liquid separator 14, an intermediate pressure side on-off valve 16a, a low pressure side on-off valve 16b, and a cooling on-off valve. 16c, bypass on-off valve 16d, low-stage fixed throttle 17, check valve 19, outdoor heat exchanger 20, cooling expansion valve 22, indoor evaporator 23, accumulator 24, and refrigerant passages 15, 18, 25, 26 Etc. The indoor condenser 12 and the indoor evaporator 23 are included in the heat pump cycle 10 and also in the indoor air conditioning unit 30.

  Among the components of the heat pump cycle 10, the compressor 11 sucks, compresses, and discharges the refrigerant in the heat pump cycle 10. That is, the fluid compressed by the compressor 11 is a refrigerant circulating in the heat pump cycle 10. Details of the structure of the compressor 11 will be described later.

  The compressor 11 has a suction port 11a, an intermediate pressure port 11b, and a discharge port 11c, and is arranged, for example, in an engine room. The suction port 11 a and the intermediate pressure port 11 b of the compressor 11 are refrigerant inlets that allow a refrigerant to flow into the compressor 11 from outside the compressor 11. On the other hand, the discharge port 11c of the compressor 11 is a refrigerant outlet through which the refrigerant flows out of the compressor 11.

  The refrigerant inlet side of the indoor condenser 12 is connected to the discharge port 11c of the compressor 11. The indoor condenser 12 is accommodated in an air-conditioning case 31 of an indoor air-conditioning unit 30 arranged in the vehicle interior. The indoor condenser 12 is an indoor heat exchanger that exchanges heat between the air passing through the indoor condenser 12 and the high-pressure refrigerant compressed by the compressor 11.

  The refrigerant outlet side of the indoor condenser 12 is connected to the inlet side of a high-stage expansion valve 13 capable of reducing the pressure of the high-pressure refrigerant flowing out of the indoor condenser 12 to an intermediate-pressure refrigerant. The high-stage expansion valve 13 is an electric variable throttle mechanism in which the valve opening is adjusted electrically. The operation of the high-stage expansion valve 13 is controlled by a control signal output from the air-conditioning control device. Further, the high-stage expansion valve 13 is configured to be able to be set to a throttle state in which a pressure reducing action is exerted and a fully open state in which no pressure reducing action is exerted.

  The outlet side of the high-stage expansion valve 13 is connected to a refrigerant inflow port 14 b of the gas-liquid separator 14. The gas-liquid separator 14 separates gas-liquid of the refrigerant flowing from the high-stage expansion valve 13 into the refrigerant inflow port 14b. The gas-liquid separator 14 is, for example, a centrifugal separator that separates gas and liquid of a refrigerant by the action of centrifugal force. The gas-liquid separator 14 is arranged outside the vehicle compartment, for example, in the engine room.

  The gas-liquid separator 14 includes a refrigerant inflow port 14b into which the refrigerant flows from the high-stage expansion valve 13, a gas-phase refrigerant outflow port 14c through which the gas-phase refrigerant separated in the gas-liquid separator 14 flows, And a liquid-phase refrigerant outflow port 14d through which the liquid-phase refrigerant separated in the gas-liquid separator 14 flows out.

  The intermediate-pressure port 11b of the compressor 11 is connected to the gas-phase refrigerant outflow port 14c of the gas-liquid separator 14 via an intermediate-pressure refrigerant passage 15, as shown in FIG. An intermediate pressure side on-off valve 16a is arranged in the intermediate pressure refrigerant passage 15. The intermediate pressure side opening / closing valve 16a is an electromagnetic valve that opens and closes the intermediate pressure refrigerant passage 15, and its operation is controlled by a control signal output from the air conditioning control device.

  The intermediate pressure side opening / closing valve 16a may be configured to exhibit a function as a check valve (that is, a check valve function) when the intermediate pressure refrigerant passage 15 is opened. The check valve function is to allow the refrigerant flow from the gas-phase refrigerant outflow port 14c of the gas-liquid separator 14 to the intermediate-pressure port 11b of the compressor 11 while allowing the refrigerant to flow from the intermediate-pressure port 11b to the gas-phase refrigerant outflow port 14c. The function is to block the flow of refrigerant to the Thereby, when the intermediate pressure side on-off valve 16a opens the intermediate pressure refrigerant passage 15, the refrigerant is prevented from flowing backward from the compressor 11 side to the gas-liquid separator 14.

  The refrigerant inlet side of the outdoor heat exchanger 20 is connected to a liquid-phase refrigerant outflow port 14 d of the gas-liquid separator 14 via a low-stage fixed throttle 17. At the same time, between the liquid-phase refrigerant outflow port 14d and the refrigerant inlet side of the outdoor heat exchanger 20 in the refrigerant flow, a fixed throttle bypass passage 18 (hereinafter, referred to as a parallel passage) provided in parallel with the low-stage fixed throttle 17 is provided. (Referred to simply as a bypass passage 18).

  The bypass passage 18 is a refrigerant passage that guides the refrigerant to the outdoor heat exchanger 20 by bypassing the low-stage fixed throttle 17 from the liquid-phase refrigerant outflow port 14d. In addition, a low-pressure side on-off valve 16b is disposed in the bypass passage 18. The low pressure side opening / closing valve 16b is an electromagnetic valve for opening / closing the bypass passage 18, and its operation is controlled by a control signal output from the air conditioning control device.

  Here, the pressure loss that occurs when the refrigerant passes through the low-pressure side on-off valve 16b is extremely smaller than the pressure loss that occurs when the refrigerant passes through the low-stage fixed throttle 17. Therefore, the refrigerant flowing out of the liquid-phase refrigerant outflow port 14d of the gas-liquid separator 14 flows into the outdoor heat exchanger 20 through the bypass passage 18 when the low-pressure side on-off valve 16b is open, and the low-pressure side When the on-off valve 16b is closed, it flows into the outdoor heat exchanger 20 via the lower fixed throttle 17.

  As the low-stage fixed throttle 17, a nozzle or an orifice having a fixed throttle opening can be employed.

  As described above, the refrigerant flows into the outdoor heat exchanger 20 shown in FIG. 1 from the liquid-phase refrigerant outflow port 14d of the gas-liquid separator 14 via the low-stage fixed throttle 17 or the bypass passage 18. The outdoor heat exchanger 20 is arranged outside the vehicle compartment such as in an engine room, for example. The outdoor heat exchanger 20 exchanges heat between the air passing through the outdoor heat exchanger 20 and the low-pressure refrigerant flowing out of the gas-liquid separator 14. The air passing through the outdoor heat exchanger 20 is, for example, air outside the vehicle that is introduced into the engine room by running the vehicle or blowing air from a blower (not shown).

  The refrigerant outlet side of the outdoor heat exchanger 20 is connected to the refrigerant inlet side of the check valve 19. The check valve 19 allows the flow of the refrigerant flowing out of the outdoor heat exchanger 20 while preventing the flow of the refrigerant toward the outdoor heat exchanger 20.

  The refrigerant outlet side of the check valve 19 is connected to the refrigerant inlet side of the cooling expansion valve 22. The cooling expansion valve 22 has the same basic configuration as the high-stage expansion valve 13 described above. That is, the cooling expansion valve 22 is an electric variable throttle mechanism, and its operation is controlled by a control signal output from the air conditioning controller. Further, the cooling expansion valve 22 is configured to be able to be set to a throttle state in which a pressure reducing action is exerted and a fully closed state in which refrigerant does not pass through the cooling expansion valve 22.

  The outlet side of the cooling expansion valve 22 is connected to the refrigerant inlet side of the indoor evaporator 23. The indoor evaporator 23 is housed in an air conditioning case 31 of the indoor air conditioning unit 30. The indoor evaporator 23 exchanges heat between the refrigerant flowing inside the indoor evaporator 23 and the air passing through the indoor evaporator 23, evaporates the refrigerant by the heat exchange, and cools the passing air.

  The outlet side of the indoor evaporator 23 is connected to the inlet side of an accumulator 24 via an evaporator pressure regulator 21 (hereinafter abbreviated as EPR 21). The EPR 21 is a pressure regulating valve that operates so as to maintain the refrigerant pressure at the outlet side of the indoor evaporator 23 at a certain value or more.

  The accumulator 24 is a low-pressure gas-liquid separator that separates gas-liquid refrigerant flowing into the accumulator 24 and stores excess refrigerant. Further, a suction port 11a of the compressor 11 is connected to a gas-phase refrigerant outlet of the accumulator 24.

  Further, an expansion valve bypass passage 25 is connected to the refrigerant outlet side of the outdoor heat exchanger 20 in parallel with the check valve 19, the cooling expansion valve 22, the indoor evaporator 23, and the EPR 21. The expansion valve bypass passage 25 is a refrigerant passage that bypasses the check valve 19, the cooling expansion valve 22, the indoor evaporator 23, and the EPR 21 and leads to the inlet side of the accumulator 24. A cooling on-off valve 16c is arranged in the expansion valve bypass passage 25. The cooling on-off valve 16c is an electromagnetic valve that opens and closes the expansion valve bypass passage 25, and its operation is controlled by a control signal output from the air conditioning control device.

  When the cooling on-off valve 16c is open, the pressure loss generated when the refrigerant passes through the cooling on-off valve 16c passes through the check valve 19, the cooling expansion valve 22, the indoor evaporator 23, and the EPR 21. Is very small with respect to the pressure loss that occurs when

  Therefore, the refrigerant flowing out of the outdoor heat exchanger 20 flows into the accumulator 24 through the expansion valve bypass passage 25 when the cooling on-off valve 16c is open, and when the cooling on-off valve 16c is closed. Flows into the accumulator 24 through the check valve 19, the cooling expansion valve 22, the indoor evaporator 23, and the EPR 21 in this order.

  Also, a refrigerant passage connecting the refrigerant outlet side of the indoor condenser 12 to the inlet side of the high-stage expansion valve 13, and a refrigerant passage connecting the refrigerant outlet side of the check valve 19 and the refrigerant inlet side of the cooling expansion valve 22. And an outdoor unit bypass passage 26 connecting the outside unit and the outside unit. A bypass opening / closing valve 16d is arranged in the outdoor unit bypass passage 26. The bypass on-off valve 16d is an electromagnetic valve for opening and closing the outdoor unit bypass passage 26, and its operation is controlled by a control signal output from the air conditioning control device.

  Next, the indoor air conditioning unit 30 will be described. The indoor air conditioning unit 30 is arranged inside the instrument panel at the forefront of the vehicle interior. As shown in FIG. 1, the indoor air-conditioning unit 30 includes an air-conditioning case 31, a blower 32, an inside / outside air switching device 33, an air mix door 34, a heater core 37, a plurality of outlet ports (not shown), the indoor condenser 12 described above. , And an indoor evaporator 23.

  The air-conditioning case 31 of the indoor air-conditioning unit 30 forms an outer shell of the indoor air-conditioning unit 30, and forms an air passage of air blown into the vehicle interior inside the air-conditioning case 31. The air conditioner case 31 houses a blower 32, a heater core 37, the indoor condenser 12, the indoor evaporator 23, and the like.

  Specifically, the air conditioning case 31 forms a warm air passage 35a and a bypass passage 35b as a part of an air passage in the air conditioning case 31. Since a partition wall 311 is provided in the air conditioning case 31 to partition the air passage downstream of the indoor evaporator 23 in the air flow, two sets of the hot air passage 35a and the bypass passage 35b are formed. I have. Thereby, the indoor air conditioning unit 30 can simultaneously blow out conditioned air having different blowing temperatures.

  Both the hot air passage 35a and the bypass passage 35b are arranged downstream of the indoor evaporator 23 in the air flow. The indoor condenser 12 and the heater core 37 are arranged in the hot air passage 35a. The heater core 37 is a heat exchanger that heats the passing air by exchanging heat between the air passing through the heater core 37 and the engine cooling water, and is disposed upstream of the indoor condenser 12 in the air flow. ing.

  The bypass passage 35b is provided in parallel with the warm air passage 35a, and allows the air from the indoor evaporator 23 to bypass the warm air passage 35a and to flow the air toward the vehicle interior.

  An inside / outside air switching device 33 that switches and introduces air inside the vehicle compartment (ie, inside air) and air outside the vehicle compartment (ie, outside air) is arranged on the most upstream side of the air flow of the air conditioning case 31. The inside / outside air switching device 33 has an inside / outside air switching door, and the inside / outside air switching door controls the opening area of the inside air introduction port for introducing inside air into the air conditioning case 31 and the opening area of the outside air introduction port for introducing outside air. Adjust continuously. As a result, the inside / outside air switching device 33 continuously changes the air flow ratio between the inside air flow and the outside air flow introduced into the air conditioning case 31.

  On the downstream side of the air flow of the inside / outside air switching device 33 and on the upstream side of the air flow of the indoor evaporator 23, there is disposed a blower 32 for blowing the air sucked through the inside / outside air switching device 33 toward the vehicle interior. I have. The blower 32 is an electric blower that drives a centrifugal multiblade fan (that is, a sirocco fan) with an electric motor. The rotation speed of the blower 32 is controlled by a control voltage output from the air conditioning control device.

  An air mixing door 34 is provided in the air-conditioning case 31. The air mixing door 34 is located on the downstream side of the air flow of the indoor evaporator 23, and is provided with air in the hot air passage 35a and the bypass passage 35b. It is located upstream of the flow. Since the air mix doors 34 are provided for each combination of the hot air passage 35a and the bypass passage 35b, a total of two air mix doors 34 are provided in the air conditioning case 31.

  For example, the air mix door 34 is a slide door device that opens and closes the entrance of the warm air passage 35a and the entrance of the bypass passage 35b. The air mix door 34 is driven by a servo motor (not shown) whose operation is controlled by a control signal output from an air conditioning control device.

  The air mix door 34 adjusts the ratio of the amount of air flowing through the warm air passage 35a to the total amount of air flowing through the warm air passage 35a and the bypass passage 35b, that is, the ratio of the amount of warm air, according to the sliding position. By adjusting the hot air flow rate, the temperature of the air blown out from the air conditioning case 31 is adjusted.

  The air mix door 34 can move continuously between the maximum cooling position and the maximum heating position, similarly to a known air mix door. The maximum cooling position is a door position where the air mix door 34 fully closes the hot air passage 35a and fully opens the bypass passage 35b. The maximum heating position is a door position where the air mix door 34 fully opens the hot air passage 35a and completely closes the bypass passage 35b.

  At the most downstream portion of the airflow of the air-conditioning case 31, there are arranged a plurality of outlets, which are a plurality of opening holes, which blow out into the vehicle compartment the combined air formed by combining the air from the warm air passage 35a and the air from the bypass passage 35b. ing. For example, as the plurality of outlets, a defroster outlet that blows conditioned air toward the inside surface of the vehicle front window glass, a face outlet that blows conditioned air toward the upper body of the occupant in the vehicle cabin, and toward the feet of the occupant A foot outlet that blows out conditioned air may be used. Each of the plurality of outlets is provided with an outlet door that opens and closes the outlet in accordance with a control signal output from the air conditioning control device.

  Next, the operation mode of the vehicle air conditioner 1 will be described. The vehicle air conditioner 1 is operated in one of a plurality of operation modes including, for example, a cooling operation mode and a heating operation mode. Hereinafter, the cooling operation mode and the heating operation mode will be described, but the vehicle air conditioner 1 may be operated in other operation modes. The operation mode may be switched manually by a switch operation of an occupant, or may be automatically switched according to various parameters such as an outside air temperature and a vehicle interior temperature.

(A) Cooling operation mode In the cooling operation mode, under the control of the air conditioning control device, the high-stage expansion valve 13 is brought into a fully opened state in which the pressure reducing effect is not exerted, and the cooling expansion valve 22 is brought into a throttled state in which the cooling operation is exerted. You. The intermediate pressure side on-off valve 16a is closed, the low pressure side on-off valve 16b is open, the cooling on-off valve 16c is closed, and the bypass on-off valve 16d is closed. You. Thereby, the heat pump cycle 10 is switched to the cooling refrigerant circuit in which the refrigerant flows as indicated by the solid line arrow FL1 in FIG.

  That is, in the heat pump cycle 10 switched to the cooling refrigerant circuit, the refrigerant discharged from the discharge port 11c of the compressor 11 is “the discharge port 11c of the compressor 11 → the indoor condenser 12 → the high-stage expansion valve 13”. → gas-liquid separator 14 → low pressure side on-off valve 16 b → outdoor heat exchanger 20 → check valve 19 → cooling expansion valve 22 → indoor evaporator 23 → EPR 21 → accumulator 24 → suction port 11a of compressor 11 in this order. Flow and circulate.

  In the cooling operation mode, the air-conditioning control device positions the air mix door 34 at the maximum cooling position. Therefore, the refrigerant circulating in the cooling refrigerant circuit passes through the indoor condenser 12 with almost no heat radiation to the blown air in the indoor condenser 12. Then, the entire amount of the blown air cooled by the indoor evaporator 23 flows into the bypass passage 35b, and the blown air is blown out into the vehicle compartment without being heated. As a result, cooling of the vehicle interior can be realized.

(B) Heating operation mode In the heating operation mode, under the control of the air conditioning control device, the high-stage expansion valve 13 is brought into the throttled state, and the cooling expansion valve 22 is brought into the fully closed state. The intermediate pressure side on-off valve 16a is in an open state, the low pressure side on-off valve 16b is in a closed state, the cooling on-off valve 16c is in an open state, and the bypass on-off valve 16d is in a closed state. You. Thereby, the heat pump cycle 10 is switched to the heating refrigerant circuit in which the refrigerant flows as indicated by the dashed arrow FL2 in FIG.

  That is, in the heat pump cycle 10 switched to the heating refrigerant circuit, the refrigerant discharged from the discharge port 11c of the compressor 11 is “the discharge port 11c of the compressor 11 → the indoor condenser 12 → the high-stage expansion valve 13”. → The gas-liquid separator 14 flows in this order.

  The gas-phase refrigerant separated by the gas-liquid separator 14 flows out of the gas-phase refrigerant outflow port 14c and flows into the intermediate pressure port 11b of the compressor 11 through the intermediate pressure refrigerant passage 15. At the same time, the liquid-phase refrigerant separated by the gas-liquid separator 14 flows out of the liquid-phase refrigerant outflow port 14d, and “the liquid-phase refrigerant outflow port 14d of the gas-liquid separator 14 → low-stage fixed throttle 17 → outdoor heat exchange. It flows in the order of the compressor 20 → the cooling on-off valve 16 c → the cooling on-off valve 16 c → the accumulator 24 → the suction port 11 a of the compressor 11.

  In the heating mode, the air-conditioning control device positions the air mix door 34 at the maximum heating position. Therefore, the refrigerant circulating in the heating refrigerant circuit radiates heat to the blown air in the indoor condenser 12 and condenses. Further, the air blown from the blower 32 passes through the indoor evaporator 23 without being cooled by the indoor evaporator 23, and the entire amount of the blown air flows to the hot air passage 35a. Then, the blown air is heated by the indoor condenser 12 and then blown into the vehicle interior. Thereby, heating of the vehicle interior can be realized.

  Further, in the heating mode, the heat pump cycle 10 is operated as a gas injection cycle that involves the compressor 11 sucking refrigerant from both the suction port 11a and the intermediate pressure port 11b.

  Next, the structure of the compressor 11 will be described. The compressor 11 shown in FIG. 2 is an electric scroll compressor, and is disposed, for example, in an engine room of a vehicle. An arrow DR1 in FIG. 2 indicates a vertical direction DR1 of the compressor 11 in a state where the compressor 11 is mounted on a vehicle.

  As shown in FIGS. 2 and 3, the compressor 11 includes, as main components, a fluid compression unit 40, an electric motor 42, a housing 44, a plurality of bearings 481, 482, 483, an eccentric shaft 50, a bush balancer 52, A discharge valve 54, a partition member 56, and a spring member 60 are provided. The housing 44 forms an outer shell of the compressor 11, and includes a motor case 45, an intermediate block 46, and a discharge block 47. The motor case 45, the intermediate block 46, and the discharge block 47 are all made of a metal such as an aluminum alloy.

  The motor case 45, the intermediate block 46, and the discharge block 47 are arranged side by side in the axial direction DRm of the motor axis CLm (hereinafter, referred to as the motor axis direction DRm), which is the rotation axis of the electric motor 42, in the order described. ing. The motor case 45, the intermediate block 46, and the discharge block 47 are integrally fixed to each other by bolting.

  The motor case 45 of the compressor 11 has a substantially cylindrical shape with a bottom, and the motor case 45 accommodates the fluid compression unit 40 and the electric motor 42. The fluid compression unit 40 is configured as a scroll-type compression mechanism that compresses a refrigerant that is a fluid, and includes a fixed scroll 401, an orbiting scroll 402, and a support member 403. As shown in FIGS. 2 and 3, the orbiting scroll 402 has a compression chamber 40a for compressing the refrigerant between the orbiting scroll 402 and the fixed scroll 401 as a non-rotating member.

  A suction port 11a is formed in the motor case 45. A refrigerant pipe from the accumulator 24 (see FIG. 1) is connected to the suction port 11a. During the compression operation of the compressor 11, the refrigerant (specifically, the gas-phase refrigerant) from the accumulator 24 is supplied to the suction port 11a. It flows into the motor case 45 through 11a. The refrigerant sucked into the motor case 45 from the suction port 11a is located at the outermost peripheral side of the moving range of the compression chamber 40a that moves from the outer peripheral side to the inner peripheral side of the fluid compression unit 40 via a refrigerant passage (not shown). Into the compression chamber 40a.

  A support member 403 fixed to the motor case 45 is disposed between the fixed scroll 401 and the rotor 422 of the electric motor 42 in the motor case 45. The support member 403 rotatably supports the rotating shaft 423 of the electric motor 42 at a first end of the rotating shaft 423 via a first bearing 481. The center of the rotating shaft 423 coincides with the motor shaft center CLm, and the axial direction of the rotating shaft 423 is the same as the motor axial direction DRm.

  The other end of the rotating shaft 423 is rotatably supported by the motor case 45 via a second bearing 482. The second bearing 482 is fitted in a second bearing recess 451 formed inside the motor case 45. The second bearing recess 451 is formed so as to be recessed in the motor case 45 toward the other side in the motor axial direction DRm. That is, the bottom surface 451a of the second bearing recess 451 faces one side in the motor axial direction DRm, that is, the fixed scroll 401 side.

  Further, the rotating shaft 423 has, at the other end in the motor axis direction DRm, another end face 423b facing the other side and orthogonal to the motor axis CLm. The rotating shaft 423 is fitted to the inner ring of the second bearing 482 such that the position of the other end surface 423b in the motor axis direction DRm is aligned with the other end surface 482a of the inner ring of the second bearing 482 (that is, the other end surface 482a of the inner ring). It is put and fixed.

  An eccentric shaft 50 protruding toward the fixed scroll 401 is provided at an end of the rotating shaft 423 on the fixed scroll 401 side (that is, one side in the motor axis direction DRm). The axis of the eccentric shaft 50 is eccentric with respect to the motor axis CLm. Therefore, the eccentric shaft 50 rotates eccentrically with respect to the motor shaft center CLm as the rotation shaft 423 rotates.

  The eccentric shaft 50 is fitted in a fitting hole of the bush balancer 52, and is rotatable relative to the bush balancer 52. The bush balancer 52 has a function as a balance weight for adjusting imbalance caused by eccentric rotation of the eccentric shaft 50 and the bush balancer 52.

  Further, the bush balancer 52 is connected to the orbiting scroll 402 via a third bearing 483 so as to be relatively rotatable.

  The orbiting scroll 402 includes a disc-shaped orbiting scroll substrate 402a and a spiral orbiting scroll wall portion 402b, and the orbiting scroll substrate 402a and the orbiting scroll wall portion 402b are integrally formed.

  The orbiting scroll substrate 402a is disposed with the motor axis direction DRm as the thickness direction of the orbiting scroll substrate 402a. The orbiting scroll wall portion 402b is formed so as to protrude from a surface 402c of the orbiting scroll substrate 402a on the compression chamber 40a side in the motor axis direction DRm, that is, one of the orbiting scroll substrate surfaces 402c in the motor axis direction DRm.

  Further, the orbiting scroll substrate 402a has a third bearing recess 402d formed on the opposite side to the orbiting scroll wall portion 402b side of the orbiting scroll substrate 402a in the motor axis direction DRm. The third bearing recess 402d is formed so as to be recessed to one side in the motor axial direction DRm on the orbiting scroll substrate 402a. That is, the bottom surface 402e of the third bearing recess 402d faces the other side in the motor axial direction DRm, that is, the second bearing 482 side. The third bearing 483 is fitted in the third bearing recess 402.

  The orbiting scroll 402 is provided with a rotation preventing mechanism (not shown) for preventing rotation of the orbiting scroll 402 (specifically, rotation of the orbiting scroll 402). Therefore, with the rotation of the rotating shaft 423 about the motor axis CLm, the orbiting scroll 402 does not rotate, but orbits around the motor axis CLm as a predetermined axis with respect to the fixed scroll 401 as a non-rotating member. In short, the orbiting scroll 402 performs a revolving orbiting motion that revolves around the motor axis CLm.

  The fixed scroll 401 is engaged with the orbiting scroll 402 so as to face in the motor axis direction DRm, and is fixed to the motor case 45. The fixed scroll 401 includes a disk-shaped fixed scroll substrate 401a and a spiral fixed scroll wall 401b, and the fixed scroll substrate 401a and the fixed scroll wall 401b are formed integrally.

  The fixed scroll substrate 401a is arranged such that the motor axis direction DRm is the thickness direction of the fixed scroll substrate 401a. At the same time, the fixed scroll board 401a is arranged such that the end surface position of the fixed scroll board 401a on the intermediate block 46 side in the motor axis direction DRm is aligned with the end of the motor case 45 on the intermediate block 46 side.

  The fixed scroll wall portion 401b is formed so as to protrude from a surface 401c of the fixed scroll substrate 401a on the compression chamber 40a side in the motor axis direction DRm, that is, the other fixed scroll substrate surface 401c on the other side in the motor axis direction DRm.

  In the compressor 11, the fixed scroll wall portion 401b of the fixed scroll 401 and the orbiting scroll wall portion 402b of the orbiting scroll 402 come into contact with each other and mesh with each other, so that compression is performed between the fixed scroll wall portion 401b and the orbiting scroll wall portion 402b. A chamber 40a is formed.

  The orbiting scroll 402 revolves around the motor axis CLm with respect to the fixed scroll 401, thereby moving the compression chamber 40 a from the outer peripheral side to the inner peripheral side (that is, the center side) of the fluid compression section 40. The volume of the compression chamber 40a is changed (specifically, reduced). Due to the change in volume of the compression chamber 40a, the orbiting scroll 402 compresses the fluid in the compression chamber 40a.

  A bypass passage 402f is formed in a portion near the center of the orbiting scroll wall 402b of the orbiting scroll 402. The bypass passage 402f is a fine hole that penetrates the orbiting scroll wall 402b and the orbiting scroll substrate 402a in the motor axis direction DRm from the tip 402g of the orbiting scroll wall 402b that slides opposite to the fixed scroll substrate surface 401c. .

  A part of the refrigerant compressed in the compression chamber 40a flows into the bypass passage 402f via a minute axial gap generated between the tip 402g of the orbiting scroll wall portion 402b and the fixed scroll substrate surface 401c. For example, in the present embodiment, a part of the refrigerant that is being compressed flows into the bypass passage 402f. The “refrigerant compressed in the compression chamber 40a” may be a refrigerant that has completed the compression process, but to be precise, is not limited to a refrigerant that has completed the compression process, and may be a refrigerant that is in the process of being compressed. Good. That is, the “refrigerant compressed in the compression chamber 40a” means a refrigerant that has been compressed at least from the start of compression in the compression chamber 40a.

  Specifically, a mixed fluid of the refrigerant and the oil flows into the bypass passage 402f. Then, the mixed fluid that has entered the bypass passage 402f passes between the inner ring and the outer ring of the third bearing 483 and the like, and is on the side opposite to the fixed scroll substrate 401a side with respect to the orbiting scroll 402, that is, the other side in the motor axis direction DRm. Is introduced into the back pressure chamber 403a provided at The mixed fluid in the back pressure chamber 403a, while lubricating each part, passes through an axial passage 423a formed in the rotating shaft 423 of the electric motor 42 and extending in the motor axial direction DRm, and the stator 421 and the rotor 422 of the electric motor 42. Flows into the space in the motor case 45 in which is disposed.

  The back pressure chamber 403a is formed inside the support member 403. That is, the support member 403 is a back pressure chamber forming part in which the back pressure chamber 403a is formed. The back pressure chamber 403a opens toward the orbiting scroll 402 in the motor axis direction DRm, and the opening of the back pressure chamber 403a is closed by the orbiting scroll 402.

  Therefore, the back pressure chamber 403a causes the pressure of the refrigerant in the back pressure chamber 403a to act as a back pressure that presses the orbiting scroll 402 against the fixed scroll 401 in the motor axis direction DRm. That is, the refrigerant in the back pressure chamber 403a urges the orbiting scroll 402 against the fixed scroll 401 in the motor axial direction DRm by the refrigerant pressure. Further, as the back pressure of the refrigerant in the back pressure chamber 403a increases, the axial gap between the tip 402g of the orbiting scroll wall portion 402b and the fixed scroll substrate surface 401c is narrowed. If the compressor 11 is in a steady operation, it is kept substantially constant.

  By appropriately generating an urging force on the orbiting scroll 402 based on the back pressure of the refrigerant in the back pressure chamber 403a, the airtightness of the compression chamber 40a is ensured, and the orbiting scroll 402 smoothly rotates with respect to the fixed scroll 401. Becomes possible.

  In the present embodiment, for example, at any of the turning positions of the orbiting scroll 402, the bypass passage 402f is provided so as to be located inside the injection passage 401e in the radial direction of the fixed scroll wall portion 401b. Therefore, when the refrigerant is supplied from the injection passage 401e to the compression chamber 40a, the refrigerant flowing from the bypass passage 402f into the back pressure chamber 403a includes the refrigerant from the injection passage 401e.

  In the fixed scroll substrate 401a of the fixed scroll 401, a discharge passage 401d penetrating the fixed scroll substrate 401a in the motor axis direction DRm is formed, and the discharge passage 401d is arranged at a central portion of the fixed scroll substrate 401a. The outlet of the discharge passage 401d is provided with a discharge valve 54 for opening and closing the discharge passage 401d. The discharge valve 54 opens when the pressure of the refrigerant in the discharge passage 401d becomes equal to or higher than a predetermined pressure.

  The fixed scroll substrate 401a is formed with a pair of injection passages 401e penetrating the fixed scroll substrate 401a in the motor axis direction DRm. Each of the pair of injection passages 401e is arranged on the outer peripheral side of the fixed scroll substrate 401a with respect to the discharge passage 401d, and is open to the intermediate block 46 side. The injection passage 401e is a passage for introducing the intermediate-pressure refrigerant flowing out of the gas-phase refrigerant outflow port 14c (see FIG. 1) of the gas-liquid separator 14 into the compression chamber 40a.

  The electric motor 42 is a drive source for driving the fluid compression unit 40. The electric motor 42 includes a stator 421 fixed to the motor case 45, a rotor 422 inserted on the inner peripheral side of the stator 421, and a rotating shaft 423 inserted on the inner peripheral side of the rotor 422. The rotor 422 is connected to the rotation shaft 423 so as not to rotate relatively. The rotor 422 and the rotation shaft 423 are rotatable relative to the stator 421.

  A three-phase alternating current is supplied to a coil included in the stator 421 from a motor drive circuit (not shown). The rotor 422 is driven to rotate by electric power supplied to the coil of the stator 421. With the rotation of the rotor 422, the orbiting scroll 402 connected to the rotating shaft 423 orbits (more specifically, revolves), and the refrigerant in the compression chamber 40a is compressed.

  Further, in the lower portion inside the motor case 45, the excess liquid-phase refrigerant 45a in the heat pump cycle 10 is stored. A part of the electric motor 42 is immersed in a liquid refrigerant 45 a in the motor case 45.

  The intermediate block 46 has an intermediate pressure port 11b, an injection relay chamber 46a, and a pair of relay holes 46b. A refrigerant pipe constituting an intermediate-pressure refrigerant passage 15 (see FIG. 1) is connected to the intermediate-pressure port 11b.

  The injection relay chamber 46a communicates with the intermediate pressure port 11b. Further, the injection relay chamber 46a communicates with a pair of injection passages 401e via a pair of relay holes 46b. Therefore, the intermediate-pressure refrigerant flowing into the intermediate-pressure port 11b is sucked from the intermediate-pressure port 11b into the compression chamber 40a through the injection relay chamber 46a, the relay hole 46b, and the injection passage 401e in this order.

  That is, in the fixed scroll 401, the injection passage 401e functions as a joining passage for joining the refrigerant introduced from the gas-liquid separator 14 outside the compressor 11 to the refrigerant being compressed in the compression chamber 40a. Note that the intermediate pressure side on-off valve 16a in FIG. 1 is in the closed state in the cooling operation mode and is opened in the heating operation mode, so that the injection passage 401e has a gas-liquid separation during the heating operation of the vehicle air conditioner 1. The refrigerant from the vessel 14 is supplied. In other words, when the indoor condenser 12 radiates heat from the refrigerant to the air blown into the vehicle interior from the refrigerant and the outdoor heat exchanger 20 absorbs heat from the external air to the refrigerant, the refrigerant from the gas-liquid separator 14 flows into the injection passage 401e. Supplied.

  A first discharge chamber 46c communicating with the discharge passage 401d through the discharge valve 54 is also formed in the intermediate block 46. The first discharge chamber 46c is provided on the fixed scroll 401 side of the intermediate block 46 with respect to the injection relay chamber 46a in the motor axis direction DRm.

  The discharge block 47 has a discharge port 11c, a second discharge chamber 47a, a communication passage 47b, and a third discharge chamber 47c. A refrigerant pipe connected to the indoor condenser 12 (see FIG. 1) is connected to the discharge port 11c. A partition member 56 is arranged between the second discharge chamber 47a and the injection relay chamber 46a, and the second discharge chamber 47a is separated from the injection relay chamber 46a by the partition member 56.

  The second discharge chamber 47a communicates with the first discharge chamber 46c via a passage (not shown) formed in the intermediate block 46. Further, the second discharge chamber 47a communicates with the third discharge chamber 47c via the communication passage 47b. The third discharge chamber 47c communicates with the discharge port 11c. Therefore, the refrigerant discharged from the compression chamber 40a to the discharge passage 401d flows from the discharge passage 401d through the first discharge chamber 46c, the second discharge chamber 47a, and the third discharge chamber 47c in that order, from the discharge port 11c to the compressor 11c. Is discharged to the outside. Note that a well-known oil separator 58 is disposed in the third discharge chamber 47c, and the oil flowing into the third discharge chamber 47c is separated by the oil separator 58 into oil mixed with the refrigerant. Then, it flows to the discharge port 11c.

  The spring member 60 shown in FIGS. 3 and 4 is a pressing device that generates a pressing force Fp for pressing the orbiting scroll 402 against the fixed scroll 401 in the motor axis direction DRm by the spring force of the spring member 60. The spring force of the spring member 60 is transmitted to the orbiting scroll substrate 402a via the rotary shaft 423 of the electric motor 42 and the bush balancer 52 in order. Therefore, the spring member 60 can make the spring force of the spring member 60 act as the pressing force Fp against the orbiting scroll 402.

  Specifically, the spring member 60 has a disk shape with a through-hole 60a in the center with the motor axial direction DRm as a thickness direction, that is, a washer shape. The spring member 60 is sandwiched between the bottom surface 451a of the second bearing recess 451 facing the motor shaft direction DRm, the other end surface 423b of the rotating shaft 423, and the other end surface 482a of the inner ring of the second bearing 482. .

  That is, since the spring member 60 is in contact with the inner ring of the second bearing 482 and the rotating shaft 423, the spring member 60 is in contact with the refrigerant in the back pressure chamber 403a via the rotating shaft 423 or with the inner ring of the second bearing 482. Heat can be exchanged via the rotating shaft 423. In short, the spring member 60 is disposed at a location where the temperature of the refrigerant in the back pressure chamber 403a can be indirectly sensed.

  The spring member 60 is formed of a bimetal washer in which a low expansion layer 601 and a high expansion layer 602 are stacked in the motor axial direction DRm. The linear expansion coefficient of the high expansion layer 602 is larger than the linear expansion coefficient of the low expansion layer 601, and the high expansion layer 602 is laminated on one side in the motor axis direction DRm, that is, on the rotation shaft 423 side, with respect to the low expansion layer 601. Have been.

  Therefore, as shown in FIG. 5, in the free state of the spring member 60, the lower the temperature of the spring member 60 is, the lower the center portion of the spring member 60 is on one side in the motor axis direction DRm (ie, It warps so as to protrude toward the high expansion layer 602 with respect to the low expansion layer 601). As the constituent materials of the low-expansion layer 601 and the high-expansion layer 602, those in which the spring member 60 becomes flat as shown in FIG.

  As shown in FIGS. 3 and 5, the spring member 60 configured as described above is configured such that the more the center portion of the spring member 60 warps so as to protrude toward one side in the motor axis direction DRm, as shown in FIGS. The inner ring is urged toward one side in the motor axial direction DRm.

  That is, due to the difference between the linear expansion coefficient of the low expansion layer 601 and the linear expansion coefficient of the high expansion layer 602, the spring member 60 increases the pressing force Fp against the orbiting scroll 402 as the temperature of the spring member 60 decreases. . In short, since the temperature of the spring member 60 corresponds to the temperature of the refrigerant in the back pressure chamber 403a, the lower the temperature of the refrigerant in the back pressure chamber 403a, the lower the pressing force Fp against the orbiting scroll 402. To increase.

  Here, the relationship between the pressure and the temperature of the refrigerant compressed by the compressor 11 will be described with reference to FIG. FIG. 6 is a time chart showing transitions of discharge refrigerant pressure PD, suction refrigerant pressure PS, discharge refrigerant temperature TD, and suction refrigerant temperature TS of compressor 11 when vehicle air conditioner 1 is operated in the heating operation mode. It is. The horizontal axis in FIG. 6 is the elapsed time, and the time t0 indicates the time when the stopped compressor 11 starts operating.

  Note that the discharge refrigerant pressure PD of the compressor 11 is a refrigerant pressure at the discharge port 11c of the compressor 11, and the suction refrigerant pressure PS is a refrigerant pressure at the suction port 11a. Further, the discharge refrigerant temperature TD is a refrigerant temperature at the discharge port 11c, and the suction refrigerant temperature TS is a refrigerant temperature at the suction port 11a.

  As shown in FIG. 6, there is a correlation between the pressures PD and PS of the refrigerant compressed by the compressor 11 and the temperatures TD and TS. This indicates that the refrigerant pressure in the back pressure chamber 403a and the refrigerant temperature are different. The same is true for relationships. That is, the refrigerant pressure and the refrigerant temperature in the back pressure chamber 403a have a correlation that the lower the refrigerant temperature, the lower the refrigerant pressure.

  As described above, the spring member 60 shown in FIG. 3 increases the pressing force Fp generated by the spring member 60 on the orbiting scroll 402 as the temperature of the refrigerant in the back pressure chamber 403a decreases. Therefore, as the refrigerant pressure in the back pressure chamber 403a decreases according to the refrigerant temperature in the back pressure chamber 403a, the pressing force Fp generated by the spring member 60 increases.

  Accordingly, when the refrigerant pressure in the back pressure chamber 403a acting as the back pressure for pressing the orbiting scroll 402 against the fixed scroll 401 in the motor axis direction DRm becomes insufficient, the pressing force Fp to the orbiting scroll 402 is appropriately adjusted. It is possible to secure. In other words, for example, when the refrigerant pressure in the back pressure chamber 403a does not rise and the refrigerant pressure is not appropriately secured to press the orbiting scroll 402 against the fixed scroll 401, for example, at the start of the heating operation, the spring member 60 It functions as a substitute for the refrigerant pressure in the pressure chamber 403a.

  Then, even if the refrigerant flowing into the suction port 11a and the intermediate pressure port 11b of the compressor 11 has a lower temperature than in the normal operation, the pressing force Fp of the spring member 60 is appropriately secured. Turns stably and can perform the optimal compression work. As a result, the vibration of the compressor 11 can be reduced, and the in-vehicle sound and the out-of-vehicle sound caused by the vibration of the compressor 11 can be reduced to improve the comfort of the occupant. Further, since the airtightness of the compression chamber 40a is appropriately secured, the compressor 11 can be operated with high efficiency, and the electric power supplied to the compressor 11 can be used efficiently and optimally.

  Further, if the material of each layer 601 and 602 of the spring member 60 is selected based on the correlation between the refrigerant pressures PD and PS and the refrigerant temperatures TD and TS shown in FIG. A stable pressing force Fp for compressing the refrigerant in the chamber 40a can be secured.

  According to the present embodiment, the spring member 60 shown in FIGS. 3 and 4 increases the pressing force Fp against the orbiting scroll 402 as the temperature of the spring member 60 decreases. And the spring member 60 is arrange | positioned in the location which can sense the temperature of the refrigerant | coolant in the back pressure chamber 403a. Therefore, the pressing device that generates the pressing force Fp against the orbiting scroll 402 can be configured as a simple structure of the spring member 60, and the pressing force Fp by the spring member 60 can be increased or decreased according to the refrigerant temperature in the back pressure chamber 403a. can do.

  Further, according to the present embodiment, the spring member 60 is formed of a bimetal washer. Then, due to the difference between the linear expansion coefficient of the low expansion layer 601 and the linear expansion coefficient of the high expansion layer 602, the spring member 60 increases the pressing force Fp against the orbiting scroll 402 as the temperature of the spring member 60 decreases. I do. Therefore, by using the relationship between the temperature of the bimetal washer and the spring force, the pressing force Fp by the spring member 60 can be increased or decreased according to the refrigerant temperature in the back pressure chamber 403a with a simple configuration.

  Further, according to the present embodiment, the refrigerant from the gas-liquid separator 14 is supplied to the injection passage 401e during the heating operation of the vehicle air conditioner 1. Therefore, the spring member 60 can generate the pressing force Fp against the orbiting scroll 402 so as to compensate for the shortage of the refrigerant pressure in the back pressure chamber 403a which tends to occur when the heating operation is started.

(2nd Embodiment)
Next, a second embodiment will be described. In the present embodiment, points different from the first embodiment will be mainly described. Further, the same or equivalent parts as those in the first embodiment will be omitted or simplified.

  As shown in FIGS. 7 and 8, the compressor 11 of the present embodiment includes the spring member 60 of the first embodiment as a first spring member 60, and further includes a second spring member 62. This embodiment is different from the first embodiment in this point.

  Specifically, the second spring member 62 of the present embodiment is a pressing device that generates a pressing force Fp on the orbiting scroll 402, similarly to the first spring member 60. Since the second spring member 62 is in contact with the orbiting scroll 402, the pressing force Fp can be applied directly to the orbiting scroll 402.

  The second spring member 62 is formed of the same bimetal washer as the first spring member 60. That is, as shown in FIG. 9, a through hole 62 a is opened in the center of the second spring member 62, and the second spring member 62 is a low expansion layer corresponding to the low expansion layer 601 of the first spring member 60. 621 and a high expansion layer 622 corresponding to the high expansion layer 602 of the first spring member 60. However, in the second spring member 62, the high expansion layer 622 is laminated on the other side of the low expansion layer 621 in the motor axis direction DRm, that is, on the rotation shaft 423 side.

  The bottom surface 402e of the third bearing recess 402d is opposed to one end surface 483a of the inner ring of the third bearing 483 (that is, one end surface 483a of the inner ring) in the motor axis direction DRm. The second spring member 62 of this embodiment is sandwiched between the bottom surface 402e of the third bearing recess 402d and the one end surface 483a of the inner ring of the third bearing 483.

  That is, the second spring member 62 can directly exchange heat with the refrigerant in the back pressure chamber 403a, and further indirectly transfers heat through the inner ring and the outer ring of the third bearing 483. It is possible to give and receive. In short, the second spring member 62 is disposed at a location where the temperature of the refrigerant in the back pressure chamber 403a can be directly or indirectly sensed.

  Since the second spring member 62 has the low expansion layer 621 and the high expansion layer 622, as shown in FIG. 10, in the free state of the second spring member 62, the lower the temperature of the second spring member 62, the lower the temperature. The central portion of the second spring member 62 warps so as to protrude toward the other side in the motor axial direction DRm (that is, toward the high expansion layer 622 with respect to the low expansion layer 621). The second spring member 62, like the first spring member 60, also has a flat plate shape as shown in FIG.

  Like the first spring member 60, the second spring member 62 configured as described above applies the pressing force Fp of the second spring member 62 to the orbiting scroll 402 shown in FIG. The lower, the larger. In short, the second spring member 62 increases the pressing force Fp of the second spring member 62 as the temperature of the refrigerant in the back pressure chamber 403a is lower.

  In the present embodiment, it is possible to obtain the same effects as those of the first embodiment, which are obtained from the same configuration as the first embodiment.

  Further, according to the present embodiment, the second spring member 62 is arranged at a position closer to the orbiting scroll 402 than the first spring member 60 is. Therefore, the second spring member 62 easily applies the pressing force Fp to the orbiting scroll 402 with an appropriate magnitude as compared with the first spring member 60.

(Other embodiments)
(1) In each of the above embodiments, since the compressor 11 forms a part of the heat pump cycle 10, the fluid compressed by the compressor 11 is the refrigerant circulating in the heat pump cycle 10, but is not limited thereto. For example, the compressor 11 may be used for applications other than the heat pump cycle 10, and the fluid compressed by the compressor 11 may be other fluid than the refrigerant.

  (2) In the above-described first embodiment, as shown in FIGS. 2 and 3, the spring member 60 is disposed at a location where the temperature of the refrigerant in the back pressure chamber 403 a can be indirectly sensed. It may be arranged at a place where the temperature of the refrigerant can be directly sensed.

  (3) In the above-described first embodiment, as shown in FIG. 4, the spring member 60 is formed of a bimetal washer. However, the spring member 60 may be formed of, for example, a shape memory alloy instead of bimetal. Further, the shape of the spring member 60 is not limited, and the spring member 60 does not need to have a washer shape. The same applies to the first and second spring members 60 and 62 of the second embodiment.

  (4) In the above-described first embodiment, the spring member 60 is provided for the second bearing 482, but any one or two of the plurality of bearings 481, 482, and 483 of the compressor 11 are provided. More than one may be provided. It is also conceivable that the spring member 60 is disposed apart from the bearings 481, 482, 483.

  The present invention is not limited to the above-described embodiment, but also includes various modifications and modifications within an equivalent range. In each of the above embodiments, it is needless to say that the elements constituting the embodiment are not necessarily essential, unless otherwise clearly indicated as essential or in principle considered to be clearly essential. No.

  In each of the above embodiments, when a numerical value such as the number, numerical value, amount, range, or the like of the constituent elements of the exemplary embodiment is mentioned, it is particularly limited to a specific number when it is clearly stated that it is essential and in principle The number is not limited to the specific number unless otherwise specified. Further, in each of the above embodiments, when referring to the material, shape, positional relationship, and the like of the components and the like, unless otherwise specified, and in principle, it is limited to a specific material, shape, positional relationship, and the like. However, the material, shape, positional relationship, and the like are not limited.

(Summary)
According to a first aspect shown in a part or all of the above embodiments, the compressor includes a pressing device that generates a pressing force for pressing the orbiting scroll against the fixed scroll in the axial direction of the predetermined axis. . Then, the pressing device increases the pressing force as the temperature of the fluid in the back pressure chamber is lower.

  According to the second aspect, the pressing device is constituted by a spring member that increases the pressing force as the temperature of the pressing device is lower, and directly or indirectly detects the temperature of the fluid in the back pressure chamber. Placed where possible. Therefore, it is possible to increase or decrease the pressing force of the pressing device according to the temperature of the fluid in the back pressure chamber while the pressing device has a simple configuration.

  According to a third aspect, the pressing device is formed of a bimetal washer and is disposed at a location where the temperature of the fluid in the back pressure chamber can be directly or indirectly sensed. The bimetal washer increases the pressing force as the temperature of the bimetal washer decreases, due to the difference between the linear expansion coefficient of the low expansion layer and the linear expansion coefficient of the high expansion layer. Therefore, it is possible to increase or decrease the pressing force by the pressing device according to the temperature of the fluid in the back pressure chamber with a simple configuration by utilizing the relationship between the temperature of the bimetal washer and the spring force.

  According to the fourth aspect, the fixed scroll is provided with a merging passage for merging the fluid introduced from the outside with the fluid being compressed in the compression chamber.

  According to the fifth aspect, in the merging passage formed in the fixed scroll, the indoor heat exchanger radiates heat from the refrigerant to the air blown into the vehicle interior, and the outdoor heat exchanger absorbs heat from the outdoor air to the refrigerant. In this case, the refrigerant flowing out of the gas-liquid separator is supplied as a fluid from outside the compressor. Therefore, the compressor provided with the pressing device is applied to a heat pump cycle that performs a heating operation.

11 Compressor 40a Compression chamber 401 Fixed scroll 402 Orbiting scroll 403 Support member (back pressure chamber forming part)
403a Back pressure chamber 60 Spring member (pressing device)
62 Second spring member (pressing device)
Fp Pressing force DRm Motor shaft direction (axial direction of predetermined shaft center)

Claims (3)

A fixed scroll (401) as a non-rotating member;
A compression chamber (40a) is formed between the fixed scroll and the fixed scroll, and the volume of the compression chamber is changed by orbiting about the predetermined axis (CLm) with respect to the fixed scroll. An orbiting scroll (402) for compressing the fluid in the compression chamber;
A back pressure chamber forming part (403) in which a back pressure chamber (403a) into which a part of the fluid compressed in the compression chamber is introduced;
A pressing device (60, 62) for generating a pressing force (Fp) for pressing the orbiting scroll against the fixed scroll in the axial direction (DRm) of the predetermined axis.
The back pressure chamber causes the pressure of the fluid in the back pressure chamber to act as a back pressure that presses the orbiting scroll against the fixed scroll in the axial direction,
The pressing device increases the pressing force as the temperature of the fluid in the back pressure chamber is lower ,
The pressing device is constituted by a bimetal washer in which a low expansion layer (601, 621) and a high expansion layer (602, 622) having a larger linear expansion coefficient than the low expansion layer are laminated in the axial direction. Disposed at a location where the temperature of the fluid in the back pressure chamber can be directly or indirectly sensed,
A compressor in which the bimetal washer increases the pressing force as the temperature of the bimetal washer becomes lower due to a difference between a linear expansion coefficient of the low expansion layer and a linear expansion coefficient of the high expansion layer . 2. The compressor according to claim 1, wherein the fixed scroll is provided with a merging passage (401 e) for merging a fluid introduced from the outside with the fluid being compressed in the compression chamber. 3. Heat pump cycle having an indoor heat exchanger (12), a gas-liquid separator (14) into which refrigerant flows from the indoor heat exchanger, and an outdoor heat exchanger (20) into which refrigerant flows from the gas-liquid separator A compressor constituting a part of (10),
The gas-liquid separator and the outdoor heat exchanger are arranged outside the vehicle compartment,
In the merging passage, the refrigerant flowing out of the gas-liquid separator is used when the indoor heat exchanger radiates heat from the refrigerant to the air blown into the vehicle interior and the outdoor heat exchanger absorbs heat from the outside air to the refrigerant. The compressor according to claim 2 , wherein the compressor is supplied as the external fluid.

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