JP2006207917A - Air conditioner and its operation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the heating of a refrigerant flowing into a compressor and to improve efficiency of the compressor. <P>SOLUTION: In this air conditioner 1 comprising the compressor 3 for compressing the refrigerant, a heat exchanging means 10 for cooling the refrigerant discharged from the compressor 3, an oil separating means 8 for removing a lubricant from the refrigerant passing through the heat exchanging means 10, an oil returning pipe 13 for returning the lubricant separated by the oil separating means 8 to the compressor 3, an oil valve for adjusting a flow rate of the lubricant returned to the compressor 3 from the oil separating means 8, and a control portion for controlling an opening of the oil valve, the oil valve is controlled in the opening direction by the control portion when a discharge temperature or a discharge pressure of the compressor 3 is over a prescribed threshold value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air conditioner and an operation method thereof.

The air conditioner includes a compressor that compresses and discharges a refrigerant, an oil separator that removes lubricating oil from the refrigerant discharged from the compressor, and a compressor or compressor that removes the lubricating oil removed by the oil separator. There is known one including an oil return pipe that returns to the suction pipe (see, for example, Patent Document 1).
JP 2000-055488 A

However, in the air conditioner described in Patent Document 1 described above, the refrigerant flowing into the compressor is heated by the high-temperature lubricating oil returned from the oil separator to the suction side of the compressor via the oil return pipe. Will be. For this reason, the density of the refrigerant flowing into the compressor is lowered, and the efficiency of the compressor is lowered.
In addition to this, especially when a cooling high load operation is performed, the ambient environmental temperature becomes high, so the discharge temperature of the compressor tends to be high, and the discharge temperature of the compressor is There is also a problem that the temperature becomes higher than the protection temperature for protection and the reliability of the compressor is lowered.

The present invention has been made in view of the above circumstances, and provides an air conditioner that can prevent the refrigerant flowing into the compressor from being heated and can improve the efficiency of the compressor, and an operating method thereof. The purpose is to do.
Another object of the present invention is to provide a method of operating an air conditioner that can reduce the discharge temperature of the compressor, particularly during cooling and high load operation, and can improve the reliability of the compressor. is there.

The present invention employs the following means in order to solve the above problems.
An air conditioner according to the present invention includes a compressor that compresses refrigerant, heat exchange means that cools the refrigerant discharged from the compressor, and oil separation means that removes lubricating oil from the refrigerant that has passed through the heat exchange means. , An oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor, an oil valve for adjusting the flow rate of the lubricating oil returned from the oil separating means to the compressor, and a radiator during cooling, An outdoor heat exchanger that operates as an evaporator during heating, an indoor heat exchanger that operates as a radiator during cooling, a heat radiator during heating, an expansion valve that squeezes and decompresses high-pressure refrigerant to form low-pressure refrigerant, and the oil valve A control unit that controls the opening of the compressor, wherein the control unit opens the oil valve when a discharge temperature or a discharge pressure of the compressor exceeds a predetermined threshold value. In Characterized in that it is your.

  An operation method of an air conditioner according to the present invention includes a compressor that compresses refrigerant, heat exchange means that cools the refrigerant discharged from the compressor, and oil that removes lubricating oil from the refrigerant that has passed through the heat exchange means. A separating means, an oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor, an oil valve for adjusting the flow rate of the lubricating oil returned from the oil separating means to the compressor, and heat dissipation during cooling An outdoor heat exchanger that operates as an evaporator during heating, an evaporator during cooling, an indoor heat exchanger that operates as a radiator during heating, an expansion valve that squeezes and decompresses high-pressure refrigerant to form low-pressure refrigerant, A control unit that controls the opening of the oil valve, and when the discharge temperature or the discharge pressure of the compressor exceeds a predetermined threshold value, Opening And controlling the.

According to such an air conditioner and its operating method, the oil valve is opened when the discharge temperature or discharge pressure of the compressor exceeds a predetermined threshold.
That is, the lubricating oil cooled by the heat exchanging means and separated by the oil separator is returned to the suction side of the compressor through the oil return pipe and the oil valve.
Thereby, it is possible to prevent the refrigerant flowing into the compressor from being heated, to reduce the temperature of the refrigerant flowing into the compressor, and to operate the compressor at the highest pressure of the COP. The efficiency of the compressor can be improved.
Moreover, since the high voltage | pressure (namely, discharge pressure) of a compressor can be raised, a heating capability can be improved.
Further, the discharge temperature of the compressor can be lowered particularly during the cooling high load operation, and the reliability of the compressor can be improved.

  In the air conditioner according to the present invention, the heat exchanging means and the oil separating means can be incorporated in the compressor.

  According to such an air conditioner, the apparatus can be reduced in size and the refrigerant circuit can be simplified.

In addition, the air conditioner and the operating method thereof according to the present invention may further include other heat exchange means for cooling the heat medium that has passed through the heat exchange means during heating with the air in the vehicle.
According to such an air conditioner and its operation method, the amount of heat of oil can be radiated into the vehicle through the heat medium during the heating operation, and the heating performance is improved.

The air conditioner according to the present invention and the operating method thereof further include other heat exchanging means for cooling the heat medium that has passed through the heat exchanging means with air in the vehicle, and controls the oil valve in the opening direction during heating operation. You can also
According to such an air conditioner and its operating method, the amount of oil circulation is increased by opening the oil valve, and a large amount of oil heat is transmitted to the heat medium in the heat exchanging means during heating operation. . Thereby, more heat quantity of oil can be radiated in the vehicle, so that the heating performance is further improved.

According to the air conditioner and the operation method thereof according to the present invention, it is possible to prevent the refrigerant flowing into the compressor from being heated and to improve the efficiency of the compressor.
Moreover, the discharge temperature of the compressor at the time of cooling high load operation can be lowered, and the reliability of the compressor can be improved.
Furthermore, the effect of improving the heating performance is obtained by radiating the heat quantity of the oil into the vehicle through the heat medium during the heating operation.

Hereinafter, a first embodiment in which an air conditioner according to the present invention is applied to a vehicle air conditioner will be described with reference to the drawings.
As shown in FIG. 1, the vehicle air conditioner 1 according to the present embodiment includes a compressor 3 that compresses a refrigerant, an exterior heat exchanger (outdoor heat exchanger) 5, and an interior heat exchanger (indoor heat). The main component is a (exchanger) 7, a first expansion valve 9, and a coolant heat exchanger (heat exchange means) 10.

The compressor 3 compresses a refrigerant (for example, carbon dioxide (CO ₂ )), and for example, a scroll compressor is used. A discharge gas temperature sensor 4 is provided on the discharge side of the compressor 3. The refrigerant compressed by the compressor 3 passes through the coolant heat exchanger 10 and the oil separator (oil separation means) 8 and is guided to the first three-way valve 12.
The vehicle exterior heat exchanger 5 exchanges heat with the outside air, and operates as a radiator during cooling and as an evaporator during heating. A second expansion valve 18 is provided in the refrigerant pipe in the vicinity of the vehicle exterior heat exchanger 5. The second expansion valve 18 is an electronic expansion valve, and is fully opened while being positioned downstream of the vehicle exterior heat exchanger 5 during cooling, and is positioned upstream of the vehicle exterior heat exchanger 5 during heating. In the state, a certain throttle is applied to depressurize the high-pressure refrigerant.

The vehicle interior heat exchanger 7 is provided in an HVAC (Heating Ventilating and Air-Conditioning) unit 11 and operates as an evaporator during cooling and as a radiator during heating.
In addition, a temperature sensor 22 is provided in the vicinity of the vehicle interior heat exchanger 7 and in the refrigerant piping that serves as the refrigerant inlet side during heating, that is, the refrigerant piping that connects the first three-way valve 12 and the vehicle interior heat exchanger 7. It has been.
The oil separator 8 removes lubricating oil from the refrigerant having a critical pressure or higher discharged from the compressor 3. The refrigerant from which the lubricating oil has been removed is guided to the first three-way valve 12 via the refrigerant pipe, and the lubricating oil is returned to the refrigerant pipe connected to the suction side of the compressor 3 via the oil return pipe 13. It is supposed to be.
One end of the oil return pipe 13 is connected to the oil separator 8, and the other end is a refrigerant pipe that connects the internal heat exchanger 20 and the compressor 3, and is located in the vicinity of the compressor 3. This is a pipe connected to the refrigerant pipe via the connection portion Ja, and an oil valve 13a (see FIG. 2) is provided in the middle thereof.

  As shown in FIG. 3, the oil valve 13 a is a so-called “electromagnetic valve with a bypass port”, and an electromagnetic valve 13 d that opens and closes the main flow path 13 b, the bypass flow path 13 c, and the bypass flow path 13 c therein. Is provided, and an electromagnet 13e for operating the electromagnetic valve 13d is disposed outside. That is, when the electromagnet 13e is energized, the electromagnetic valve 13d moves from the position of the solid line in the figure to the position of the two-dot chain line against the urging force of the spring member 13f, and the bypass flow path 13c is opened. . On the other hand, when energization to the electromagnet 13e is stopped, the electromagnetic valve 13d is moved from the position of the two-dot chain line in the figure to the position of the solid line by the urging force of the spring member 13f, and the bypass flow path 13c is closed. .

  The first expansion valve 9 is an electronic expansion valve and is provided in a refrigerant pipe in the vicinity of the vehicle interior heat exchanger 7 and throttles the high-pressure refrigerant in a state of being positioned upstream of the vehicle interior heat exchanger 7 during cooling. The refrigerant is depressurized to form a low-pressure refrigerant, and is fully opened in a state of being positioned downstream of the vehicle interior heat exchanger 7 during heating.

  The coolant heat exchanger 10 receives engine coolant of an engine (vehicle drive device) 14 that drives a vehicle, and high-temperature and high-pressure refrigerant (and lubricating oil contained in the refrigerant) compressed by the compressor 3. It is intended to exchange heat. In the coolant heat exchanger 10, heat is transferred (sucked) from the refrigerant side to the engine cooling water side, and the refrigerant discharged from the compressor 3 (and the lubricating oil contained in the refrigerant). For example, the temperature is lowered from 140 ° C. to 90 ° C. The cooling water (heat medium) exchanged by the coolant heat exchanger 10 is guided to a heater core (other heat exchange means) 16 provided in the HVAC unit 11 described later and then returned to the engine 14. Is done.

  The first three-way valve 12 switches the refrigerant flow, and switches to the vehicle exterior heat exchanger 5 side during cooling and to the vehicle interior heat exchanger 7 side during heating. In FIG. 1, the refrigerant flow during cooling is indicated by a dotted line, and the refrigerant flow during heating is indicated by a solid line.

  An internal heat exchanger 20 is provided in the refrigerant pipe between the second expansion valve 18 and the first expansion valve 9. This internal heat exchanger 20 exchanges heat between the high-pressure side refrigerant and the low-pressure refrigerant on the suction side of the compressor 3, and provides supercooling to the high-pressure refrigerant that has passed through the outdoor heat exchanger 5 during cooling. It is used to lower the dryness of the refrigerant at the entrance of the vehicle interior heat exchanger 7.

  The HVAC unit 11 provided with the vehicle interior heat exchanger 7 and the heater core 16 adjusts the temperature of the air (outside air or vehicle interior air) supplied to the vehicle interior, and from the upstream side (left side in the figure). The blower 24, the vehicle interior heat exchanger 7 and the heater core 16 are sequentially provided. An air mix damper 26 is provided on the upstream side of the heater core 16. By adjusting the opening degree of the air mix damper 26, the flow rate of the cold air that has passed through the vehicle interior heat exchanger 7 flows through the heater core 16.

An accumulator 28 is provided on the suction side of the compressor 3 and on the upstream side of the internal heat exchanger 20. The accumulator 28 separates gas and liquid in the refrigerant.
A second three-way valve 30 is provided between the accumulator 28 and the vehicle interior heat exchanger 7. The second three-way valve 30 connects the vehicle interior heat exchanger 7 and the internal heat exchanger 20 during cooling, and connects the accumulator 28 and the vehicle exterior heat exchanger 5 during heating.

The rotation frequency of the compressor 3, the switching of the three-way valves 12, 30 and the opening adjustment of the electronic expansion valves 9, 18 and the oil valve 13a are controlled by a control unit (not shown) based on the measured values of the temperature sensors 4, 22, etc. Done.
Here, the opening / closing operation of the electromagnetic valve 13d (adjustment of the opening degree of the oil valve 13a) will be described in more detail with reference to FIG.
The controller determines whether or not the current compressor discharge temperature obtained by the discharge gas temperature sensor 4 (see FIG. 1) is higher than the threshold value T1 (S0). As a result, the current compressor discharge temperature is set to the threshold value T1. If it is higher, the electromagnetic valve 13d is forcibly opened (S1), and if the current compressor discharge temperature is equal to or lower than the threshold T1, the electromagnetic valve 13d is forcibly closed. (S2).

The vehicle air conditioner 1 configured as described above operates as follows.
During cooling (see the dotted line in FIG. 1), the temperature of the refrigerant (including the lubricating oil) compressed by the compressor 3 is lowered by the coolant heat exchanger 10, and the oil separator 8 lubricates the refrigerant in the refrigerant. After the oil is removed, the oil flows through the first three-way valve 12 to the vehicle exterior heat exchanger 5. The compressed refrigerant is in a supercritical state because carbon dioxide is used as the refrigerant.
In the vehicle exterior heat exchanger 5, heat is exchanged with the outside air, and the high-pressure refrigerant is cooled. That is, the vehicle exterior heat exchanger 5 operates as a radiator.
The high-pressure refrigerant radiated by the heat exchanger 5 outside the passenger compartment passes through the fully opened second expansion valve 18 and is led to the internal heat exchanger 20. In the internal heat exchanger 20, heat is exchanged with the low-pressure refrigerant on the suction side of the compressor 3, and the high-pressure refrigerant is supercooled.
The high-pressure refrigerant that has passed through the internal heat exchanger 20 is throttled and depressurized by the first expansion valve 9. The refrigerant decompressed by the first expansion valve 9 becomes a low-pressure refrigerant and is led to the vehicle interior heat exchanger 7.
In the vehicle interior heat exchanger 7, heat exchange is performed between the air (outside air or vehicle interior air) guided from the blower 24 and the low-pressure refrigerant, and the low-pressure refrigerant evaporates. That is, the vehicle interior heat exchanger 7 operates as an evaporator. The amount of heat is deprived by the latent heat of vaporization of the liquid refrigerant, and the air is cooled and guided to the downstream heater core 16.
The refrigerant evaporated in the vehicle interior heat exchanger 7 becomes a low-pressure gas refrigerant, and is guided to the accumulator 28 through the second three-way valve 30. After the gas and liquid are separated by the accumulator 28, the low-pressure gas refrigerant takes heat from the high-pressure refrigerant by the internal heat exchanger 20 and is guided to the suction side of the compressor 3.

  In the HVAC unit 11, air (outside air or vehicle interior air) introduced from the blower 24 is cooled by the vehicle interior heat exchanger 7, and then warmed by the heater core 16 into which engine cooling water is introduced, and guided to the vehicle interior. It is burned. Cooling water that has cooled the discharge gas from the compressor 3 is guided to the heater core 16, and the amount of heat taken from the discharge gas can be effectively radiated by the heater core 16. The amount of heating given to the air by the heater core 16 is adjusted by the air mix damper 26.

During heating (see the solid line in FIG. 1), the temperature of the refrigerant (including lubricating oil) compressed by the compressor 3 is lowered by the coolant heat exchanger 10, and the oil separator 8 lubricates the refrigerant. After the oil is removed, the oil is guided to the vehicle interior heat exchanger 7 through the first three-way valve 12. The compressed refrigerant is in a supercritical state because carbon dioxide is used as the refrigerant.
In the vehicle interior heat exchanger 7, heat is exchanged between the air introduced from the blower 24 and the high-pressure refrigerant to warm the air. That is, the vehicle interior heat exchanger 7 operates as a radiator.
The high-pressure refrigerant that has radiated heat in the vehicle interior heat exchanger 7 passes through the fully opened first expansion valve 9 and is led to the internal heat exchanger 20.
In the internal heat exchanger 20, the high-pressure refrigerant is cooled by exchanging heat with the low-pressure refrigerant on the suction side of the compressor 3.
The high-pressure refrigerant that has passed through the internal heat exchanger 20 is throttled and depressurized by the second expansion valve 18, becomes low-pressure refrigerant, and is led to the vehicle exterior heat exchanger 5. The exterior heat exchanger 5 exchanges heat with the outside air and evaporates the low-pressure refrigerant. That is, the vehicle exterior heat exchanger 5 operates as an evaporator.
The low-pressure gas refrigerant evaporated in the vehicle exterior heat exchanger 5 passes through the second three-way valve 30 and is separated from the gas-liquid by the accumulator 28, and then takes heat from the high-pressure refrigerant in the internal heat exchanger 20, and is sucked into the compressor 3. Guided to the side.

  In the HVAC unit 11, the air (outside air or vehicle interior air) introduced from the blower 24 is heated by the vehicle interior heat exchanger 7, and then further heated by the heater core 16 into which engine cooling water is introduced, into the vehicle interior. Led. Cooling water that has cooled the discharge gas from the compressor 3 is guided to the heater core 16, and the amount of heat taken from the discharge gas can be effectively radiated by the heater core 16. The amount of heating given to the air by the heater core 16 is adjusted by the air mix damper 26.

According to the air conditioner 1 according to the present embodiment, when the compressor discharge temperature (discharge temperature of the compressor 3) is higher than T1, the electromagnetic valve 13d of the oil valve 13a provided in the oil return pipe 13 is opened. It is supposed to be.
That is, the relatively low-temperature lubricating oil cooled by the coolant heat exchanger 10 and separated by the oil separator 8 is returned to the suction side of the compressor 3 through the oil return pipe 13 and the oil valve 13a. It has become.
Thereby, it is possible to prevent the refrigerant flowing into the compressor from being heated, to reduce the temperature of the refrigerant flowing into the compressor, and to operate the compressor at the highest pressure of the COP. The efficiency of the compressor can be improved.
Moreover, since the high voltage | pressure (namely, discharge pressure) of a compressor can be raised, a heating capability can be improved.
Further, the discharge temperature of the compressor can be lowered particularly during the cooling high load operation, and the reliability of the compressor can be improved.

A second embodiment in which the air conditioner according to the present invention is applied to a vehicle air conditioner will be described with reference to FIG.
The vehicle air conditioner according to the present embodiment uses the compressor discharge pressure instead of the compressor discharge temperature, and the oil valve is opened and closed by estimating the compressor discharge temperature from the measured value of the compressor discharge pressure. This differs from that of the first embodiment described above. Since other components are the same as those in the above-described embodiment, description of these components is omitted here.

As shown in FIG. 5, the controller determines whether or not the current compressor discharge pressure obtained by the discharge pressure sensor (not shown) is higher than a threshold value P1 (S3). When the discharge pressure is higher than the threshold value P1, the electromagnetic valve 13d is forcibly opened (S4), and when the current compressor discharge pressure is less than or equal to the threshold value P1, the electromagnetic valve 13d is forcibly closed. (S5).
Since the operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

A third embodiment in which the air conditioner according to the present invention is applied to a vehicle air conditioner will be described with reference to FIG.
The vehicle air conditioner according to the present embodiment includes not only the compressor discharge temperature but also a step for determining an operation mode, that is, a step for determining whether the current operation state is heating or cooling. It differs from that of the first embodiment described above. Since other components are the same as those in the above-described embodiment, description of these components is omitted here.

As shown in FIG. 6, first, the control unit determines whether the current operation state is heating or cooling (S6). In the case of heating, the electromagnetic valve 13d is forcibly opened in order to sufficiently return the cooled lubricating oil from the oil separator 8 to the compressor 3 (S7).
On the other hand, in the case of cooling, the process proceeds from S6 to S8, and the control unit determines whether or not the current compressor discharge temperature obtained by the discharge gas temperature sensor 4 is higher than the threshold T1 (S8). If the current compressor discharge temperature is higher than the threshold T1, the electromagnetic valve 13d is forcibly opened (S9). If the current compressor discharge temperature is equal to or lower than the threshold T1, the electromagnetic valve 13d is forcibly opened. (S10).
Since the operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

A fourth embodiment in which the air conditioner according to the present invention is applied to a vehicle air conditioner will be described with reference to FIG.
The vehicle air conditioner according to this embodiment differs from that of the third embodiment described above in that the oil valve is opened and closed according to the compressor discharge temperature even during heating operation. Since other components are the same as those in the above-described embodiment, description of these components is omitted here.

As shown in FIG. 7, first, the control unit determines whether the current operation state is heating or cooling (S11). In the case of heating, the electromagnetic valve 13d is forcibly opened so that the cooled lubricating oil sufficiently returns from the oil separator 8 to the compressor 3 (S12).
On the other hand, in the case of cooling, the process proceeds from S11 to S13, and the controller determines whether or not the current compressor discharge pressure obtained by the discharge pressure sensor (not shown) is higher than the threshold value P1 (S3). As a result, when the current compressor discharge pressure is higher than the threshold value P1, the solenoid valve 13d is forcibly opened (S14). When the current compressor discharge pressure is less than or equal to the threshold value P1, the solenoid valve 13d. Is forcibly closed (S15).
Since the operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

8th Embodiment which applied the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles is described using FIG.
The vehicle air conditioner according to the present embodiment includes not only a compressor discharge temperature but also an operation mode, that is, a step (step) for determining whether the current operation state is heating or cooling. During operation, the oil valve is opened and closed according to the outside air temperature (outdoor temperature), which is different from the above-described embodiment. Since other components are the same as those in the above-described embodiment, description of these components is omitted here.

As shown in FIG. 8, first, the control unit determines whether the current operation state is heating or cooling (S16). In the case of heating, the process proceeds from S16 to S17, and the control unit determines whether or not the current compressor discharge temperature obtained by the discharge gas temperature sensor 4 is higher than the threshold T1 (S17). When the compressor discharge temperature is higher than the threshold T1, the solenoid valve 13d is forcibly opened (S18). When the current compressor discharge temperature is equal to or lower than the threshold T1, the solenoid valve 13d is forcibly closed. (S19).
On the other hand, in the case of cooling, the process proceeds from S16 to S20, and the control unit determines whether or not the current outside air temperature obtained by the outside air temperature sensor (not shown) is higher than the threshold value T2 (S20). As a result, when the current outside air temperature is higher than the threshold value T2, the electromagnetic valve 13d is forcibly opened (S21), and when the current outside air temperature is equal to or lower than the threshold value T2, the electromagnetic valve 13d is forced. Is closed (S22).
Since the operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

A sixth embodiment in which the air conditioner according to the present invention is applied to a vehicle air conditioner will be described with reference to FIG.
The vehicle air conditioner in the present embodiment includes the oil separator 8, a part of the oil return pipe 13, the oil valve 13 a, the refrigerant discharged from the compressor 3, and the refrigerant inside the compressor 3. This is different from the above-described embodiment in that a compressor cooling pipe (heat exchanging means) for cooling the lubricating oil is provided. Since other components are the same as those in the above-described embodiment, description of these components is omitted here.

  As shown in FIG. 9, in this embodiment, the compressor 40 compresses the refrigerant | coolant gas which is arrange | positioned in this housing 41 and was taken in in the sealed space m, for example in the housing 41 which has the sealed space m inside. This is a scroll compressor constituted mainly by a scroll compression mechanism 42 and a rotary shaft 43 that drives the scroll compression mechanism 42.

The housing 41 includes, for example, a first housing 44, a second housing 45, a third housing 46, and a fourth housing 47. After combining these, a plurality of bolts (not shown) or the like are used. By being coupled, a sealed space m is formed inside. Reference numerals 48, 49, and 50 denote O-rings that seal the joint portion between the first housing 44 and the fourth housing 47 to keep the sealed space m sealed.
A suction port 45a for sucking refrigerant gas is formed in the upper part of the second housing 45 so as to communicate with the sealed space m. The upper part of the fourth housing 47 is compressed by the scroll compression mechanism 42, and the oil A discharge port 47a for discharging the compressed refrigerant gas after the lubricating oil in the refrigerant gas is separated by the separation chamber (oil separation means) 51 is formed. The space formed in the lower part of the third housing 46 and the fourth housing 47 is the lubricating oil separated by the oil separation chamber 51 (that is, after the lubrication of the scroll compression mechanism 42 and the sealing of the compression chamber C are performed). The oil storage chamber 52 stores a lubricating oil).
The oil separation chamber 51 is a cylindrical space. In the oil separation chamber 51, an inner cylinder 53 having a hollow cylindrical shape and a substantially T-shape in cross section is arranged.

The scroll compression mechanism 42 includes a fixed scroll 59 and a turning scroll 60.
The fixed scroll 59 includes a fixed end plate 59a and a spiral wall body 59b standing on the inner surface thereof, and a discharge port 59c is formed at the center of the fixed end plate 59a. The discharge port 59c is opened and closed by a discharge valve 62 attached to the rear surface (back surface) of the fixed end plate 59a via a bolt (not shown).

The orbiting scroll 60 includes an orbiting end plate 60a and a spiral wall body 60b standing on the inner surface thereof. An eccentric bush 65 is rotatably fitted through a needle bearing 66 in a boss 60c erected on the outer surface of the swivel end plate 60a. An eccentric pin 43a that protrudes from the end of this is fitted. A plurality of compression chambers C are formed by causing the fixed scroll 59 and the orbiting scroll 60 to be eccentric from each other by a predetermined distance and mesh with each other while shifting the angle by 180 degrees.
An Oldham ring (rotation prevention mechanism) 67 is provided between the orbiting scroll 60 and the second housing 45, and the orbiting scroll 60 rotates around the eccentric bush 65 when the rotating shaft 43 is rotated. It is supposed not to. Therefore, when the rotating shaft 43 is rotated, the orbiting scroll 60 does not rotate but only performs a revolving orbiting motion. Further, the eccentric bush 65 is provided with a balance weight 68 so as to cancel the centrifugal force accompanying the revolution of the orbiting scroll 60.

The rotating shaft 43 is a rotor shaft that rotates about its axis by a driving mechanism (not shown) such as an engine or an electric motor, and the above-described eccentric pin 43a having an eccentric axis is projected from the tip thereof. The rotation shaft 43 is supported by a first bearing (not shown) provided in the first housing 44 and a second bearing 70 provided in the second housing 45 so as to be rotatable around the axis. .
Note that an electromagnetic clutch (not shown) is provided at the other end of the rotating shaft 43 (the end located on the side opposite to the eccentric pin 43a), so that driving force from an engine or an electric motor (not shown) is provided. The rotation shaft 43 may or may not be transmitted.

  In the scroll compressor 40 having such a structure, when an electromagnetic clutch is engaged, a driving force from an engine, an electric motor, or the like is transmitted to the rotating shaft 43 and the rotating shaft 43 is rotated, and this rotation is eccentric pin 43a. Then, it is transmitted to the orbiting scroll 60 of the scroll compression mechanism 42 via the eccentric bush 65 and the boss 60c. The orbiting scroll 60 is configured to perform a revolving orbiting motion on a circular orbit having a revolution orbiting radius as a radius while being prevented from rotating by the Oldham ring 67.

  Then, the refrigerant gas enters the sealed space m of the housing 41 through the suction port 45a, and is sucked into the compression chamber C of the scroll compression mechanism 42 through a path not shown. Then, as the volume of the compression chamber C decreases due to the revolving orbiting motion of the orbiting scroll 60, the refrigerant gas reaches the center while being compressed, and contains lubricating oil from the discharge port 59c through the discharge chamber 71 and the communication hole 72. The refrigerant is guided to the oil separation chamber 51 and swirled along the inner wall surface of the oil separation chamber 51. As a result, the lubricating oil mixed in the refrigerant falls down while turning along the inner wall surface of the oil separation chamber 51 by the centrifugal separation action and is stored in the oil storage chamber 52, while the lubricating oil is The separated refrigerant is discharged to the outside through the inside of the inner cylinder 53 and the discharge port 47 a of the fourth housing 47.

The lubricating oil LO stored in the oil storage chamber 52 is supplied to the scroll compressor via an oil return path 59d formed in the third housing 46 and an oil return pipe (not shown) communicating with the oil return path 59d. 40 is returned to the refrigerant pipe connected to the suction side, that is, the suction port 45a.
In the middle of the oil return path 59d, an oil valve 80 having the same configuration as the oil valve 13a described above, a so-called “electromagnetic valve with a bypass port” is provided. The oil valve 80 in the present embodiment is configured such that an electromagnetic valve (not shown) disposed therein is opened / closed by an electromagnet 80a disposed outside the scroll compressor 40.
A compressor cooling pipe (heat exchange means) 81 is provided in the third housing 46. The engine cooling water of the engine (vehicle drive device) 14 described above is passed (passed) through the compressor cooling pipe 81, thereby the engine cooling water and the compressor 40. The high-temperature and high-pressure refrigerant (and the lubricating oil contained in this refrigerant) compressed by the heat exchange is exchanged. That is, the heat of the refrigerant discharged from the compressor 40 (and the lubricating oil contained in the refrigerant) is taken away by the engine cooling water, and the temperature of the refrigerant (and the lubricating oil contained in the refrigerant) becomes For example, the temperature can be lowered from 140 ° C. to 90 ° C. The cooling water that has passed through the compressor cooling pipe 81 is guided to the heater core 16 provided in the HVAC unit 11 described above, and then returned to the engine 14.
With the scroll compressor 40 having such a configuration, the apparatus can be miniaturized and the refrigerant circuit can be simplified.
Since other operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

In addition, this invention is not limited to the thing of embodiment mentioned above, For example, instead of the bypass port solenoid valve mentioned above, for example, a temperature type control valve with a bypass port, a constant pressure valve with a bypass port, or a differential pressure valve with a bypass port Etc. can also be provided.
Also, instead of providing these valves with bypass ports, two oil return pipes are provided, and only one of them is provided with a solenoid valve, a temperature control valve, a constant pressure valve, or a differential pressure valve. You can also.

It is a schematic block diagram which shows the example which applied 1st Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles. It is an expanded sectional view of the oil separator shown in FIG. It is an expanded sectional view of the oil valve shown in FIG. It is a flowchart for demonstrating the method of control of the oil valve of the air conditioning apparatus shown in FIG. It is a figure which shows the example which applied 2nd Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles, Comprising: It is a flowchart for demonstrating the method of control of an oil valve. It is a figure which shows the example which applied 3rd Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles, Comprising: It is a flowchart for demonstrating the method of control of an oil valve. It is a figure which shows the example which applied 4th Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles, Comprising: It is a flowchart for demonstrating the method of control of an oil valve. It is a figure which shows the example which applied 5th Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles, Comprising: It is a flowchart for demonstrating how to control an oil valve. It is a principal part expanded sectional view which shows the example which applied 6th Embodiment of the air conditioning apparatus by this invention to the air conditioning apparatus for vehicles.

Explanation of symbols

1 Vehicle air conditioner (air conditioner)
3 Compressor 5 Outside heat exchanger (outdoor heat exchanger)
7 Car interior heat exchanger (indoor heat exchanger)
8 Oil separator (oil separation means)
9 First expansion valve 10 Coolant heat exchanger (heat exchange means)
13 Oil return pipe 13a Oil valve 18 Second expansion valve 51 Oil separation chamber (oil separation means)
80 Oil valve 81 Compressor cooling pipe (heat exchange means)

Claims (7)

A compressor for compressing the refrigerant;
Heat exchange means for cooling the refrigerant discharged from the compressor;
Oil separating means for removing lubricating oil from the refrigerant that has passed through the heat exchange means;
An oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor;
An oil valve for adjusting the flow rate of lubricating oil returned from the oil separation means to the compressor;
An outdoor heat exchanger that operates as a radiator during cooling and as an evaporator during heating;
An indoor heat exchanger that operates as an evaporator during cooling and as a radiator during heating;
An expansion valve that squeezes and decompresses the high-pressure refrigerant to form a low-pressure refrigerant;
A controller for controlling the opening of the oil valve, and an air conditioner comprising:
When the discharge temperature or discharge pressure of the compressor exceeds a predetermined threshold, the control unit controls the oil valve in the opening direction.   The air conditioning apparatus according to claim 1, wherein the heat exchange means and the oil separation means are built in the compressor. 3. The air conditioner according to claim 1, further comprising another heat exchanging unit that cools the heat medium that has passed through the heat exchanging unit with air in the vehicle during heating. A compressor for compressing the refrigerant;
Heat exchange means for cooling the refrigerant discharged from the compressor;
Other heat exchange means for cooling the heat medium that has passed through the heat exchange means with the air inside the vehicle,
Oil separation means for removing lubricating oil from the refrigerant that has passed through the heat exchange means;
An oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor;
An oil valve for adjusting the flow rate of lubricating oil returned from the oil separation means to the compressor;
An outdoor heat exchanger that operates as a radiator during cooling and as an evaporator during heating;
An indoor heat exchanger that operates as an evaporator during cooling and as a radiator during heating;
An expansion valve that squeezes and decompresses the high-pressure refrigerant to form a low-pressure refrigerant;
A controller for controlling the opening of the oil valve, and an air conditioner comprising:
The air conditioner is characterized in that the oil valve is controlled in the opening direction by the controller during heating operation. A compressor for compressing the refrigerant;
Heat exchange means for cooling the refrigerant discharged from the compressor;
Oil separation means for removing lubricating oil from the refrigerant that has passed through the heat exchange means;
An oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor;
An oil valve for adjusting the flow rate of lubricating oil returned from the oil separation means to the compressor;
An outdoor heat exchanger that operates as a radiator during cooling and as an evaporator during heating;
An indoor heat exchanger that operates as an evaporator during cooling and as a radiator during heating;
An expansion valve that squeezes and decompresses the high-pressure refrigerant to form a low-pressure refrigerant;
A control unit for controlling the opening degree of the oil valve, and an operation method of an air conditioner comprising:
An operation method of an air conditioner, wherein the oil valve is controlled in an opening direction when a discharge temperature or a discharge pressure of the compressor exceeds a predetermined threshold value.   6. The method of operating an air conditioner according to claim 5, further comprising other heat exchanging means for cooling the heat medium that has passed through the heat exchanging means by the air in the vehicle during heating. A compressor for compressing the refrigerant;
Heat exchange means for cooling the refrigerant discharged from the compressor;
Oil separation means for removing lubricating oil from the refrigerant that has passed through the heat exchange means;
Other heat exchange means for cooling the heat medium that has passed through the heat exchange means with the air inside the vehicle,
An oil return pipe for returning the lubricating oil separated by the oil separating means to the compressor;
An oil valve for adjusting the flow rate of lubricating oil returned from the oil separation means to the compressor;
An outdoor heat exchanger that operates as a radiator during cooling and as an evaporator during heating;
An indoor heat exchanger that operates as an evaporator during cooling and as a radiator during heating;
An expansion valve that squeezes and decompresses the high-pressure refrigerant to form a low-pressure refrigerant;
A control unit for controlling the opening degree of the oil valve, and an operation method of an air conditioner comprising:
An operation method of an air conditioner, wherein the oil valve is controlled to open in a heating operation.

Images