JP2011255856A - Air conditioner for vehicle and control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle which can maintain a good operation, and to provide a control valve suitable for the air conditioner for a vehicle.SOLUTION: The air conditioner 1 for a vehicle includes a compressor 2, an outdoor heat exchanger 5, an indoor evaporator 7 and an auxiliary condenser 3. An overheat degree control valve 32 is disposed in a position downstream of the indoor heat exchanger 5 during a heating operation. The overheat degree control valve 32 includes: a body provided with an inlet port to introduce a refrigerant from the upstream, an outlet port to introduce the refrigerant to the downstream, and a main valve hole communicating the inlet port and the outlet port; a valve driving body including a main valve element that contacts or detaches from the valve hole to adjust a valve open degree; and a temperature sensing part that senses the temperature and pressure of the refrigerant flowing in an inner passage connecting the inlet port and the outlet port, and drives to open or close the main valve element to control the overheat degree of the refrigerant to a set degree.

Description

  The present invention relates to a heat pump vehicle air conditioner capable of dehumidifying and heating a vehicle interior, and a control valve suitable for the vehicle air conditioner.

  In recent years, in vehicles equipped with an internal combustion engine, the combustion efficiency of the engine has improved, and it has become difficult for the cooling water used as a heat source to rise to the temperature required for heating. On the other hand, in a hybrid vehicle using both an internal combustion engine and an electric motor, the utilization rate of the internal combustion engine is low, so that it is more difficult to use such cooling water. There is no heat source by an internal combustion engine in an electric vehicle. For this reason, a heat pump type vehicle air conditioner that performs cycle operation using a refrigerant not only for cooling but also for heating to dehumidify and heat the vehicle interior has been proposed (see, for example, Patent Document 1).

  Such a vehicle air conditioner has a refrigeration cycle including a compressor, an outdoor heat exchanger, an evaporator, an indoor heat exchanger, etc., and the function of the outdoor heat exchanger is switched between heating operation and cooling operation. It is done. During the heating operation, the outdoor heat exchanger functions as an evaporator. At that time, the indoor heat exchanger dissipates heat while the refrigerant circulates through the refrigeration cycle, and the air in the passenger compartment is heated by the heat. On the other hand, the outdoor heat exchanger functions as a condenser during the cooling operation. At that time, the refrigerant condensed in the outdoor heat exchanger evaporates in the evaporator, and the air in the passenger compartment is cooled by the latent heat of evaporation. At that time, dehumidification is also performed.

Japanese Patent Laid-Open No. 9-240266

  However, in such a vehicle air conditioner, if sufficient refrigerant is not supplied to the evaporator and the degree of superheat (spar heat) on the outlet side may become excessive, the evaporator has temperature unevenness. It will occur. Lubricating oil is generally circulated in the refrigerant circuit of the vehicle air conditioner. However, if such temperature unevenness occurs in the evaporator, it is assumed that the oil stays in the evaporator. . If so, sufficient oil may not be supplied to the compressor, which may hinder its operation.

  One of the objects of the present invention is to provide a vehicle air conditioner capable of ensuring good operation and a control valve suitable for the vehicle air conditioner.

  In order to solve the above problems, a control valve according to an aspect of the present invention communicates an inlet port for introducing a refrigerant from the upstream side, an outlet port for leading the refrigerant to the downstream side, and the inlet port and the outlet port. A body provided with a main valve hole, a valve drive body including a main valve body that adjusts the valve opening degree by contacting and separating from the main valve hole, and a temperature of refrigerant flowing through an internal passage that connects the inlet port and the outlet port; A temperature sensing unit that senses pressure and opens and closes the main valve body so that the degree of superheat of the refrigerant reaches the set superheat degree.

  Here, the “temperature sensing unit” senses the temperature and pressure of the refrigerant introduced from the inlet port, and opens and closes the main valve body so that the superheat degree of the refrigerant introduced through the inlet port becomes the set superheat degree. It may be driven. Alternatively, the main valve body may be driven to open and close such that the temperature and pressure of the refrigerant derived from the outlet port are sensed and the degree of superheat of the refrigerant derived via the outlet port becomes the set superheat degree. Alternatively, the temperature and pressure of the refrigerant in the middle portion of the internal passage connecting the inlet port and the outlet port may be sensed, and the main valve body may be driven to open and close so that the superheat degree of the refrigerant becomes the set superheat degree.

  According to this aspect, the superheat degree of the refrigerant passing through the superheat degree control valve can be controlled to an appropriate value. For this reason, for example, by providing the superheat degree control valve on the downstream side of the evaporator in the refrigeration cycle, it is possible to reduce temperature unevenness in the evaporator. As a result, the circulation of oil flowing through the refrigerant circuit can be maintained well. The superheat degree control valve of this aspect is also suitable for the refrigeration cycle of the vehicle air conditioner as described below.

  A vehicle air conditioner according to an aspect of the present invention includes a compressor that compresses and discharges a refrigerant, and an outdoor condenser that is disposed outside the passenger compartment and dissipates the refrigerant during cooling operation, while evaporating the refrigerant during heating operation. An outdoor heat exchanger that functions as an outdoor evaporator, an indoor evaporator that is disposed inside the vehicle and evaporates the refrigerant, an auxiliary condenser that dissipates the refrigerant separately from the outdoor heat exchanger, and cooling operation and heating operation The first refrigerant circulation passage that can circulate so that the refrigerant discharged from the compressor sometimes returns to the compressor via the auxiliary condenser and the indoor evaporator in order, and the refrigerant discharged from the compressor during the heating operation is auxiliary condensed A second refrigerant circulation passage that can be circulated so as to return to the compressor via the heat exchanger and the outdoor heat exchanger, and the refrigerant discharged from the compressor during the cooling operation sequentially passes through the outdoor heat exchanger and the indoor evaporator. Pressure A third refrigerant circulation passage which can be circulated back to the machine, and a first valve which is provided downstream of the auxiliary condenser and adjusts the flow rate of the refrigerant supplied to the indoor evaporator via the first refrigerant circulation passage A second valve that is provided downstream of the auxiliary condenser and that adjusts the flow rate of the refrigerant supplied to the outdoor heat exchanger via the second refrigerant circulation passage, and is provided in the second refrigerant circulation passage. A superheat degree control valve that adjusts the flow rate of the refrigerant so that the superheat degree on the outlet side of the outdoor heat exchanger when the heat exchanger functions as an outdoor evaporator becomes the set superheat degree.

  Here, the “auxiliary condenser” may dissipate the circulating refrigerant separately from the outdoor heat exchanger, may be an indoor condenser provided in the vehicle interior, or may be a first condenser provided outside the vehicle interior. Two outdoor condensers may be used. The “first valve” and the “second second valve” may have their valve opening adjusted by an actuator. For example, the valve opening degree may be controlled to a set opening degree by an actuator such as a stepping motor. Alternatively, the valve opening degree may be controlled to a set opening degree set by a supply current value by an actuator such as a solenoid. Each valve may be a proportional valve whose valve opening changes proportionally by driving of an actuator. The “set superheat degree” can be appropriately set to a value that can prevent or suppress temperature unevenness in the outdoor heat exchanger.

  According to this aspect, the refrigerant condensed in the auxiliary condenser passes through at least one of the first valve and the second valve, and is supplied to each of the indoor evaporator and the outdoor heat exchanger. That is, the ratio of the flow rate of the refrigerant supplied to the indoor evaporator and the outdoor heat exchanger is adjusted by the first valve and the second valve. This makes it possible to supply an appropriate amount of refrigerant to the indoor evaporator. In particular, the superheat degree on the outlet side of the outdoor evaporator (outdoor heat exchanger) can be appropriately controlled by the superheat degree control valve. For this reason, it becomes possible to reduce the temperature nonuniformity in the outdoor heat exchanger. As a result, the circulation of oil flowing through the refrigerant circuit can be maintained well.

  ADVANTAGE OF THE INVENTION According to this invention, the control valve suitable for the air conditioning apparatus for vehicles which can ensure favorable operation | movement, and the air conditioning apparatus for vehicles can be provided.

1 is a system configuration diagram illustrating a schematic configuration of a vehicle air conditioning apparatus according to a first embodiment. It is explanatory drawing showing operation | movement of the vehicle air conditioner. It is sectional drawing showing the specific structure and operation | movement of a superheat degree control valve. It is sectional drawing showing the specific structure and operation | movement of a superheat degree control valve. It is sectional drawing showing the structure and operation | movement of a superheat degree control valve which concern on 2nd Embodiment. It is sectional drawing showing the structure and operation | movement of a superheat degree control valve which concern on 2nd Embodiment. It is sectional drawing showing the structure and operation | movement of a superheat degree control valve which concern on 2nd Embodiment. It is sectional drawing showing the structure and operation | movement of a superheat degree control valve which concern on 2nd Embodiment. It is sectional drawing showing the specific structure of the 1st control valve unit which concerns on 3rd Embodiment. It is explanatory drawing showing the operation state of a 1st control valve unit. It is explanatory drawing showing the operation state of a 1st control valve unit. It is explanatory drawing showing the operation state of a 1st control valve unit. It is sectional drawing showing the structure and operation | movement of the 1st control valve unit which concern on 4th Embodiment. It is sectional drawing showing the structure and operation | movement of the 1st control valve unit which concern on 4th Embodiment.

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

[First Embodiment]
First, a first embodiment of the present invention will be described. FIG. 1 is a system configuration diagram illustrating a schematic configuration of the vehicle air conditioning apparatus according to the first embodiment. In the present embodiment, the vehicle air conditioning apparatus of the present invention is embodied as an electric vehicle air conditioning apparatus.

  The vehicle air conditioner 1 includes a refrigeration cycle in which a compressor 2, an indoor condenser 3, a first control valve unit 4, an outdoor heat exchanger 5, a second control valve unit 6, an evaporator 7 and an accumulator 8 are connected by piping. (Refrigerant circuit). The vehicle air conditioner 1 is a heat pump type air conditioner that performs air conditioning in the vehicle interior using the heat of the refrigerant in a process in which alternative refrigerant (HFC-134a) as a refrigerant circulates while changing its state in the refrigeration cycle. It is configured as.

  The vehicle air conditioner 1 is also operated so as to switch a plurality of refrigerant circulation passages between the cooling operation and the heating operation. The refrigeration cycle is configured such that the indoor condenser 3 and the outdoor heat exchanger 5 can operate in parallel as a condenser, and the evaporator 7 and the outdoor heat exchanger 5 can operate in parallel as an evaporator. It is configured. That is, a first refrigerant circulation passage through which the refrigerant circulates during the cooling operation and the heating operation, a second refrigerant circulation passage through which the refrigerant circulates only during the heating operation, and a third refrigerant circulation passage through which the refrigerant circulates only during the cooling operation are formed. .

  The first refrigerant circulation passage is a passage through which the refrigerant circulates as follows: compressor 2 → indoor condenser 3 → second control valve unit 6 → evaporator 7 → accumulator 8 → compressor 2. The second refrigerant circulation passage is a passage through which the refrigerant circulates like the compressor 2 → the indoor condenser 3 → the second control valve unit 6 → the outdoor heat exchanger 5 → the first control valve unit 4 → the accumulator 8 → the compressor 2. It is. The third refrigerant circulation passage is a passage through which the refrigerant circulates like the compressor 2 → the first control valve unit 4 → the outdoor heat exchanger 5 → the second control valve unit 6 → the evaporator 7 → the accumulator 8 → the compressor 2. is there. The refrigerant flow through the outdoor heat exchanger 5 is reversed between when the second refrigerant circulation passage is opened and when the third refrigerant circulation passage is opened. That is, the refrigerant inlet and outlet in the outdoor heat exchanger 5 are switched between when the second refrigerant circulation passage is opened and when the third refrigerant circulation passage is opened.

  Specifically, a passage leading to the discharge chamber of the compressor 2 is branched, one of the first passages 21 is connected to the inlet of the indoor condenser 3, and the other second passage 22 is connected to the outdoor heat exchanger 5. Connected to one doorway. The third passage 23 connected to the outlet of the indoor condenser 3 branches on the downstream side thereof, and the first branch passage 26 on one side thereof is connected to the evaporator 7 via the fourth passage 24 and the second branch on the other side. The passage 27 is connected to the other entrance / exit of the outdoor heat exchanger 5 through the fifth passage 25. The fourth passage 24 and the fifth passage 25 are connected by a connection passage 28. In addition, a bypass passage 29 is branched at an intermediate portion of the second passage 22 and is connected to the accumulator 8 and the compressor 2. Further, a return passage 30 connected to the outlet of the evaporator 7 is connected to the bypass passage 29 on the downstream side of the check valve 33 (described later), and is connected to the accumulator 8 and the compressor 2.

  The first refrigerant circulation passage is configured by connecting the first passage 21, the third passage 23, the first branch passage 26, the fourth passage 24, and the return passage 30. The second refrigerant circulation passage is configured by connecting the first passage 21, the third passage 23, the second branch passage 27, the fifth passage 25, the second passage 22, and the bypass passage 29. The third refrigerant circulation passage is configured by connecting the second passage 22, the fifth passage 25, the connection passage 28, the fourth passage 24, and the return passage 30. And in order to implement | achieve such switching of a refrigerant circulation path, the 1st control valve unit 4 is provided in the connection part of the compressor 2 and the outdoor heat exchanger 5, and the indoor condenser 3 and the outdoor heat exchanger 5 are provided. A second control valve unit 6 is provided at the connection between the evaporator 7 and the evaporator 7.

  The vehicle air conditioner 1 has a duct 10 in which heat exchange of air is performed, and an indoor blower 12, an evaporator 7, and an indoor condenser 3 are arranged from the upstream side of the air flow direction in the duct 10. An air mix door 14 is rotatably provided on the upstream side of the indoor condenser 3, and the ratio between the air volume passing through the indoor condenser 3 and the air volume bypassing the indoor condenser 3 is adjusted. Moreover, the outdoor air blower 16 is arrange | positioned so that the outdoor heat exchanger 5 may be opposed.

  The compressor 2 is configured as an electric compressor that houses a motor and a compression mechanism in a housing, is driven by a supply current from a battery (not shown), and the discharge capacity of the refrigerant changes according to the rotational speed of the motor. As this compressor 2, various types of compressors such as a reciprocating type, a rotary type and a scroll type can be adopted. However, since the electric compressor itself is publicly known, the description thereof is omitted.

  The indoor condenser 3 is provided in the vehicle interior and functions as an auxiliary condenser that dissipates the refrigerant separately from the outdoor heat exchanger 5. That is, the high-temperature and high-pressure refrigerant discharged from the compressor 2 dissipates heat when passing through the indoor condenser 3. The air distributed according to the opening degree of the air mix door 14 undergoes heat exchange in the process of passing through the indoor condenser 3.

  The outdoor heat exchanger 5 is disposed outside the passenger compartment and functions as an outdoor condenser that radiates the refrigerant that passes through the interior during the cooling operation, and functions as an outdoor evaporator that evaporates the refrigerant that passes through the interior during the heating operation. The outdoor blower 16 is a suction type blower, and introduces outside air by rotationally driving an axial fan with a motor. The outdoor heat exchanger 5 exchanges heat between the outside air and the refrigerant.

  The evaporator 7 is arrange | positioned in a vehicle interior, and functions as an indoor evaporator which evaporates the refrigerant | coolant which passes the inside. That is, the refrigerant that has become low temperature and low pressure by passing through each control valve (described later) constituting the second control valve unit 6 evaporates when passing through the evaporator 7. The air introduced from the upstream side of the duct 10 is cooled by the latent heat of vaporization. At this time, the cooled and dehumidified air is distributed into one that passes through the indoor condenser 3 and one that bypasses the indoor condenser 3 according to the opening of the air mix door 14. The air passing through the indoor condenser 3 is heated during the passage process. The air that has passed through the indoor condenser 3 and the bypassed air are mixed on the downstream side of the indoor condenser 3, adjusted to a target temperature, and supplied to the interior of the vehicle from a blower outlet (not shown). For example, the air is blown out from a vent outlet, a foot outlet, a differential outlet, or the like toward a predetermined position in the vehicle interior.

  The accumulator 8 is a device that separates and stores the refrigerant sent from the evaporator, and has a liquid phase part and a gas phase part. For this reason, even if liquid refrigerant more than expected is derived from the evaporator 7, the liquid refrigerant can be stored in the liquid phase part, and the refrigerant in the gas phase part can be derived to the compressor 2. As a result, the compression operation of the compressor 2 is not hindered. On the other hand, in the present embodiment, a part of the refrigerant in the liquid phase portion can be supplied to the compressor 2, and a necessary amount of lubricating oil can be returned to the compressor 2.

  The first control valve unit 4 includes a switching valve 31, a superheat degree control valve 32 and a check valve 33. The switching valve 31 is a two-way electromagnetic valve that includes a valve portion that opens and closes the second passage 22 and a solenoid that drives the valve portion. The flow of the refrigerant from the compressor 2 to the outdoor heat exchanger 5 through the second passage 22 is permitted by opening the switching valve 31. In the present embodiment, an on-off valve (an on / off valve) that opens and closes the valve portion depending on whether or not the solenoid is energized is used as the switching valve 31. Note that the actuator that drives the valve portion of the switching valve 31 may not be a solenoid, but may be an electric motor such as a stepping motor.

  The superheat degree control valve 32 controls the flow of the refrigerant so that the superheat degree (superheat) on the outlet side of the outdoor heat exchanger 5 approaches a predetermined superheat degree (set superheat degree SH) during the heating operation. It is a control valve. In the present embodiment, as the superheat degree control valve 32, a mechanical control valve having a temperature sensing unit that senses the temperature and pressure of the refrigerant on the outlet side of the outdoor heat exchanger 5 and drives the valve unit is used. The superheat degree control valve 32 reduces the valve opening degree when the detected superheat degree is larger than the set superheat degree SH, and raises the evaporation pressure of the outdoor heat exchanger 5, thereby allowing the refrigerant to pass through the outdoor heat exchanger 5. The amount of heat exchange with the external air is reduced, thereby reducing the degree of superheat to approach the set superheat degree SH.

  On the contrary, if the detected superheat degree is smaller than the set superheat degree SH, the superheat degree control valve 32 increases the valve opening degree and reduces the evaporation pressure of the outdoor heat exchanger 5, thereby causing the outdoor heat exchanger 5 to open. The amount of heat exchange between the refrigerant passing through 5 and the external air is increased, thereby increasing the degree of superheat and bringing it closer to the set degree of superheat SH. Thus, the superheat degree control valve 32 operates autonomously so that the superheat degree on the outlet side of the outdoor heat exchanger 5 approaches the set superheat degree SH. The specific configuration of the superheat degree control valve 32 will be described in detail later.

  The check valve 33 is configured as a mechanical valve that prevents the refrigerant from flowing back to the superheat control valve 32 side in the bypass passage 29. The check valve 33 is a differential pressure valve that autonomously opens when the front-rear differential pressure (the differential pressure between the upstream pressure and the downstream pressure of the check valve 33) exceeds a set value (a preset valve opening differential pressure). It may be.

  The second control valve unit 6 includes a supercooling degree control valve 41 (first supercooling degree control valve), a proportional valve 42, a supercooling degree control valve 43 (second supercooling degree control valve), and a check valve 44. including. The supercooling degree control valve 41 functions as an “expansion device” that squeezes and expands the refrigerant introduced from the indoor condenser 3 via the third passage 23 and leads it to the downstream side, and from the indoor condenser 3 to the evaporator. 7 and the “total flow valve” that adjusts the total flow rate of the refrigerant supplied to the outdoor heat exchanger 5.

  The supercooling degree control valve 41 is a control valve that controls the flow of the refrigerant so that the supercooling degree (subcool) on the outlet side of the indoor condenser 3 approaches a predetermined supercooling degree (set value SC1). . In the present embodiment, as the supercooling degree control valve 41, a mechanical control valve having a temperature sensing unit that senses the temperature and pressure of the refrigerant on the outlet side of the indoor condenser 3 and drives the valve unit is used. The supercooling degree control valve 41 operates in the valve opening direction when the supercooling degree on the outlet side of the indoor condenser 3 becomes larger than the set value SC1, and increases the flow rate of the refrigerant flowing through the indoor condenser 3. When the flow rate of the refrigerant increases in this way, the condensing capacity per unit flow rate of the refrigerant in the indoor condenser 3 decreases, so that the degree of supercooling decreases.

  Conversely, when the degree of supercooling on the outlet side of the indoor condenser 3 becomes smaller than the set value SC1, the supercooling degree control valve 41 operates in the valve closing direction to decrease the flow rate of the refrigerant flowing through the indoor condenser 3. . When the flow rate of the refrigerant is thus reduced, the condensation capacity per unit flow rate of the refrigerant in the indoor condenser 3 is increased, so that the degree of supercooling is increased. Thus, the supercooling degree control valve 41 operates autonomously so that the supercooling degree at the inlet (the outlet side of the indoor condenser 3) becomes the set value SC1.

  The proportional valve 42 is configured as a three-way electromagnetic proportional valve, and is provided at a branch point where the third passage 23 branches into the first branch passage 26 and the second branch passage 27. That is, the proportional valve 42 is configured as a “composite valve” including a first proportional valve that controls the opening degree of the first branch passage 26 and a second proportional valve that controls the opening degree of the second branch passage 27. Yes.

  The first proportional valve adjusts the opening degree of the first refrigerant circulation passage by controlling the opening degree of the valve portion. The second proportional valve adjusts the opening degree of the second refrigerant circulation passage by controlling the opening degree of the valve portion. The first proportional valve and the second proportional valve are integrally provided with valve bodies constituting the respective valve portions, and are linearly controlled simultaneously by one actuator. Thereby, the ratio of the opening degree of each valve part is controlled. That is, during the heating operation, the total flow rate of the refrigerant supplied to the evaporator 7 and the outdoor heat exchanger 5 is adjusted by the supercooling degree control valve 41, and the total flow rate is distributed to the ratio set by the proportional valve 42. It is done. That is, the proportional valve 42 functions as a “distribution valve” that distributes the flow rate of the refrigerant according to the drive amount of the actuator. In the present embodiment, the actuator of the proportional valve 42 is a solenoid, but in a modification, it may be a stepping motor.

  The supercooling degree control valve 43 serves as an “expansion device” that expands and expands the refrigerant introduced from the outdoor heat exchanger 5 through the fifth passage 25 and the connection passage 28 to the evaporator 7 side during cooling operation. Function. The supercooling degree control valve 43 is a control valve that controls the flow of refrigerant so that the supercooling degree on the outlet side of the outdoor heat exchanger 5 approaches a predetermined supercooling degree (set value SC2) during cooling operation. It is. In the present embodiment, as the supercooling degree control valve 43, a mechanical control valve having a temperature sensing section that drives the valve section by sensing the temperature and pressure of the refrigerant on the outlet side of the outdoor heat exchanger 5 during the cooling operation. Is used. The supercooling degree control valve 43 operates in the valve opening direction when the supercooling degree on the outlet side of the outdoor heat exchanger 5 becomes larger than the set value SC2, and increases the flow rate of the refrigerant flowing through the outdoor heat exchanger 5. When the flow rate of the refrigerant increases in this way, the condensing capacity per unit flow rate of the refrigerant in the outdoor heat exchanger 5 decreases, so that the degree of supercooling decreases.

  Conversely, when the degree of supercooling on the outlet side of the outdoor heat exchanger 5 becomes smaller than the set value SC2, the supercooling degree control valve 43 operates in the valve closing direction, and the flow rate of the refrigerant flowing through the outdoor heat exchanger 5 is reduced. Decrease. When the flow rate of the refrigerant decreases in this way, the condensation capacity per unit flow rate of the refrigerant in the outdoor heat exchanger 5 increases, so that the degree of supercooling increases. Thus, the supercooling degree control valve 43 operates autonomously so that the supercooling degree at the inlet (outlet side of the outdoor heat exchanger 5) becomes the set value SC2.

  The check valve 44 is configured as a mechanical valve that prevents the refrigerant from flowing back to the supercooling degree control valve 43 side in the connection passage 28.

  The vehicle air conditioner 1 configured as described above is controlled by the control unit 100. The control unit 100 includes a CPU that executes various arithmetic processes, a ROM that stores various control programs, a RAM that is used as a work area for data storage and program execution, an input / output interface, and the like. Signals from various sensors and switches (not shown) installed in the vehicle air conditioner 1 are input to the control unit 100. The control unit 100 calculates the control amount of each actuator in order to realize the room temperature set by the vehicle occupant, and outputs a control signal to the drive circuit of each actuator. The control unit 100 also performs drive control of the compressor 2, the indoor fan 12, the outdoor fan 16, and the air mix door 14 in addition to opening / closing control of the switching valve 31 and the proportional valve 42.

  The control unit 100 includes a drive signal output unit that outputs a pulse signal set in the drive circuit of the proportional valve 42. Specifically, a PWM output unit is provided that outputs a pulse signal having a set duty ratio, which is calculated by the control unit 100. However, since the configuration itself is a known one, a detailed description will be given. Omitted. The control unit 100 determines the set opening of the proportional valve 42 based on predetermined external information detected by various sensors such as the temperature inside and outside the vehicle interior, the temperature of the air blown from the evaporator 7, and the opening is Supply current to the solenoid so that the set opening is reached. As a modification, when the actuator of the proportional valve 42 is configured by a stepping motor, a control pulse signal is output to the stepping motor so that the opening degree becomes the set opening degree.

  By such control, as shown in the figure, the compressor 2 introduces the refrigerant having the suction pressure Ps through the suction chamber, compresses the refrigerant, and discharges it as the refrigerant having the discharge pressure Pd. At this time, the pressure in the second control valve unit 6 is as shown. That is, the upstream side of the supercooling degree control valve 41 becomes a high pressure upstream pressure P1, and the downstream side of the first proportional valve in the proportional valve 42 becomes a low pressure downstream pressure P3. Further, an intermediate pressure P2 is provided on the downstream side of the second proportional valve in the proportional valve 42 and on the upstream side of the supercooling degree control valve 43.

  Next, operation | movement of the refrigerating cycle of this embodiment is demonstrated. FIG. 2 is an explanatory diagram illustrating the operation of the vehicle air conditioner. (A) shows the state during cooling operation, (B) shows the state during heating operation, (C) shows the state during specific heating operation, and (D) shows the state during special air conditioning operation. Yes. The “cooling operation” here is an operation state in which the cooling function functions more than the heating function, and the “heating operation” is an operation state in which the heating function functions more than the cooling function. Further, the “specific heating operation” is a heating operation in which the evaporator 7 does not function (substantially no cooling function). The “special air conditioning operation” is a cooling operation and a heating operation in which the outdoor heat exchanger 5 does not function.

  The upper part of each figure shows a Mollier diagram for explaining the operation of the refrigeration cycle. The horizontal axis represents enthalpy, and the vertical axis represents various pressures. The lower part of each figure shows the operating state of the refrigeration cycle. Thick lines and arrows in the figure indicate the flow of the refrigerant, and symbols a to g correspond to those in the Mollier diagram. Further, “x” in the figure indicates that the flow of the refrigerant is blocked. The lower part of the figure corresponds to FIG. 1, but is simplified for convenience, for example, illustration of the air mix door 14 is omitted.

  As shown in FIG. 2A, the switching valve 31 is opened in the first control valve unit 4 during the cooling operation. On the other hand, in the second control valve unit 6, the first proportional valve of the proportional valve 42 is opened, and the second proportional valve is closed. At this time, since the degree of superheat at the outlet of the compressor 2 is large, the degree of superheat control valve 32 is kept closed. For this reason, the bypass passage 29 is blocked, and the refrigerant discharged from the compressor 2 is guided to the outdoor heat exchanger 5. At this time, the outdoor heat exchanger 5 functions as an outdoor condenser. That is, the refrigerant discharged from the compressor 2 is circulated through the first refrigerant so as to pass through the indoor condenser 3, the supercooling degree control valve 41, the first proportional valve of the proportional valve 42, the evaporator 7, and the accumulator 8. Circulate through the passage and return to the compressor 2, and circulate through the third refrigerant circulation passage through the switching valve 31, the outdoor heat exchanger 5, the supercooling degree control valve 43, the evaporator 7, and the accumulator 8. Return to the compressor 2.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed by passing through the indoor condenser 3 on the one hand and the outdoor heat exchanger 5 on the other hand. Then, the refrigerant passing through the indoor condenser 3 is adiabatically expanded by the supercooling degree control valve 41, and is introduced into the evaporator 7 as a cold / low pressure gas-liquid two-phase refrigerant. At this time, the supercooling degree control valve 41 autonomously adjusts the opening degree of the valve portion so that the supercooling degree on the outlet side (point c) of the indoor condenser 3 becomes the set value SC1. Since the second proportional valve of the proportional valve 42 is closed, all the refrigerant expanded by the supercooling degree control valve 41 passes through the first proportional valve of the proportional valve 42 and is supplied to the evaporator 7.

  Further, the refrigerant passing through the outdoor heat exchanger 5 is adiabatically expanded by the supercooling degree control valve 43 and is introduced into the evaporator 7 as a cold / low pressure gas-liquid two-phase refrigerant. At this time, the supercooling degree control valve 43 autonomously adjusts the opening degree of the valve portion so that the supercooling degree on the outlet side (point f) of the indoor condenser 3 becomes the set value SC2. In the present embodiment, the set values SC1 and SC2 are set equal (denoted as “SC”), but in a modified example, they may be different from each other. The refrigerant introduced into the inlet of the evaporator 7 evaporates in the process of passing through the evaporator 7 and cools the air in the passenger compartment. At this time, the refrigerant derived from the evaporator 7 is introduced into the compressor 2 through the accumulator 8, and then the lubricating oil is returned to the compressor 2.

  On the other hand, as shown in FIG. 2B, the switching valve 31 is closed in the first control valve unit 4 during the heating operation. On the other hand, in the second control valve unit 6, the first proportional valve and the second proportional valve of the proportional valve 42 are both opened, and the ratio of the opening degree of both proportional valves is adjusted, whereby the evaporator 7 and the outdoor heat exchange are adjusted. The flow rate of the refrigerant toward the vessel 5 is distributed. At this time, the outdoor heat exchanger 5 functions as an outdoor evaporator. That is, the refrigerant discharged from the compressor 2 is circulated through the first refrigerant so as to pass through the indoor condenser 3, the supercooling degree control valve 41, the first proportional valve of the proportional valve 42, the evaporator 7, and the accumulator 8. Circulating the passage and returning to the compressor 2, on the other hand, passing through the indoor condenser 3, the supercooling degree control valve 41, the second proportional valve of the proportional valve 42, the outdoor heat exchanger 5, the superheat degree control valve 32, and the accumulator 8. In this manner, the refrigerant circulates in the second refrigerant circulation passage and returns to the compressor 2.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed through the indoor condenser 3. Then, the cold / low pressure gas-liquid two-phase refrigerant adiabatically expanded by the supercooling degree control valve 41 is distributed by the proportional valve 42, and one of the distributed refrigerant is supplied to the evaporator 7 to be evaporated and distributed. The other refrigerant thus supplied is supplied to the outdoor heat exchanger 5 to evaporate. At this time, the ratio of evaporation in both the outdoor heat exchanger 5 and the evaporator 7 is controlled by the ratio of the opening degrees of the first proportional valve and the second proportional valve. Thereby, the evaporation amount in the evaporator 7 can be secured, and the dehumidifying function can be secured. Further, the lubricating oil can be returned to the compressor 2 without being retained in the evaporator 7. In addition, since the inlet side of the supercooling degree control valve 43 is not in a supercooling state, the supercooling degree control valve 43 maintains a closed state.

  In this heating operation, it is necessary to perform the dehumidification operation satisfactorily. The outline of the dehumidification control is as follows. That is, as shown in FIG. 2 (B), the predetermined supercooling degree SC at the outlet of the indoor condenser 3 is maintained by the supercooling degree control valve 41 (point c), so that the condensing capacity in the indoor condenser 3 is maintained. Is maintained appropriately and efficient heat exchange is performed (point d). On the other hand, the state of the refrigerant at the inlet of the compressor 2 is always maintained on the saturated vapor pressure curve by the accumulator 8 (point a). On the other hand, the state of refrigerant at the outlet of the evaporator 7 (point e) changes so as to balance with the state of refrigerant at the outlet of the outdoor heat exchanger 5 (point g).

  That is, the wetness of the refrigerant at the outlet of the evaporator 7 balances with the superheat of the refrigerant at the outlet of the outdoor heat exchanger 5. At this time, the amount of heat absorbed from the outside in the outdoor heat exchanger 5 is adjusted by the amount of restriction of the superheat degree control valve 32. That is, the superheat degree control valve 32 operates in the valve closing direction to increase the evaporation pressure Po in the outdoor heat exchanger 5 when the superheat degree on the outlet side of the outdoor heat exchanger 5 becomes larger than the set superheat degree SH. As a result, a differential pressure Poe between the evaporation pressure Po of the outdoor heat exchanger 5 and the evaporation pressure Pe of the evaporator 7 is generated. As a result, the temperature of the refrigerant passing through the outdoor heat exchanger 5 increases and the amount of heat exchange with the outside air decreases, so the degree of superheat changes in a decreasing direction.

  On the contrary, when the superheat degree becomes smaller than the set superheat degree SH, the evaporating pressure Po in the outdoor heat exchanger 5 is lowered by operating in the valve opening direction. Thereby, the temperature of the refrigerant passing through the outdoor heat exchanger 5 is lowered and the amount of heat exchange with the outside air is increased, so that the degree of superheat changes in a direction of increasing. Thus, since the superheat degree control valve 32 operates autonomously so that the superheat degree on the outlet side of the outdoor heat exchanger 5 becomes the set superheat degree SH, the superheat degree on the outlet side of the outdoor heat exchanger 5 is excessive. It is prevented from becoming. Thereby, the temperature nonuniformity of the outdoor heat exchanger 5 can be suppressed, and the retention of the lubricating oil in the outdoor heat exchanger 5 can be prevented or suppressed.

  The control unit 100 increases the degree of opening of the second proportional valve in accordance with the rotational speed of the compressor 2 to increase the outdoor heat exchange when a preset condition is established that the lubricating oil stays in the outdoor heat exchanger 5. Circulating lubricating oil is ensured by flowing a wet refrigerant to the outlet side of the vessel 5. In that case, the superheat control valve 32 operates in the valve opening direction to return the superheat, but since there is a time lag until the temperature sensing part senses, the lubricating oil is derived together with the wet refrigerant. It becomes possible to do. In the present embodiment, an example in which the degree of superheat is generated in the outdoor heat exchanger 5 has been shown. However, when the specification is such that the degree of superheat is generated in the evaporator 7, superheat degree control is performed downstream of the evaporator 7. A control valve similar to the valve 32 may be provided.

  In addition, as shown in FIG. 2C, the switching valve 31 is closed in the first control valve unit 4 during the specific heating operation. On the other hand, in the second control valve unit 6, the first proportional valve of the proportional valve 42 is closed and the second proportional valve is opened. For this reason, the refrigerant does not pass through the evaporator 7, and the evaporator 7 substantially does not function. That is, only the outdoor heat exchanger 5 functions as an evaporator. That is, the refrigerant discharged from the compressor 2 passes through the second refrigerant circulation passage so as to pass through the indoor condenser 3, the second proportional valve of the proportional valve 42, the outdoor heat exchanger 5, the superheat degree control valve 32, and the accumulator 8. And return to the compressor 2. In addition, since the inlet side of the supercooling degree control valve 43 is not in a supercooling state, the supercooling degree control valve 43 maintains a closed state.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed through the indoor condenser 3 and is adiabatically expanded by the supercooling degree control valve 41 to become a cold / low-pressure gas-liquid two-phase refrigerant. It evaporates through the heat exchanger 5. The refrigerant that has passed through the outdoor heat exchanger 5 returns to the compressor 2 through the superheat degree control valve 32 and the accumulator 8. That is, since the cold / low pressure refrigerant is not heat-exchanged in the evaporator 7, the air introduced into the passenger compartment is only heated by the indoor condenser 3. Thus, since the low-temperature and low-pressure liquid refrigerant is temporarily not supplied to the evaporator 7, the evaporator 7 is warmed by the air passing through the duct 10. When the control unit 100 determines that the external environment is extremely low according to the external temperature or the like, the control unit 100 appropriately switches from the heating operation to the specific heating operation, thereby preventing or suppressing the evaporator 7 from freezing.

  Further, as shown in FIG. 2D, the switching valve 31 is closed in the first control valve unit 4 during the special cooling / heating operation. In the second control valve unit 6, the first proportional valve of the proportional valve 42 is opened and the second proportional valve is closed. For this reason, the refrigerant does not pass through the outdoor heat exchanger 5, and the outdoor heat exchanger 5 substantially does not function. That is, only the evaporator 7 is in a state of inside air circulation that functions as an evaporator. That is, the refrigerant discharged from the compressor 2 passes through the first refrigerant circulation passage through the indoor condenser 3, the supercooling degree control valve 41, the first proportional valve of the proportional valve 42, the evaporator 7, and the accumulator 8. Circulate and return to the compressor 2. At this time, the evaporation pressure Po of the outdoor heat exchanger 5 is lower than the suction pressure Ps of the compressor 2, but the check valve 44 prevents the refrigerant from flowing backward to the supercooling degree control valve 43 side. The stop valve 33 also prevents the refrigerant from flowing back to the switching valve 31 side.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed through the indoor condenser 3 and is adiabatically expanded by the supercooling degree control valve 41 to become a cold / low-pressure gas-liquid two-phase refrigerant and evaporate. It passes through the vessel 7 and is evaporated. The refrigerant that has passed through the evaporator 7 returns to the compressor 2 via the accumulator 8. The air introduced into the passenger compartment is cooled and dehumidified via the evaporator 7 and heated by the indoor condenser 3 to adjust its temperature. Such special air conditioning operation functions effectively when it is difficult to absorb heat from the outside, for example, when the vehicle is placed in an extremely cold state.

  Next, a specific configuration and operation of the first control valve unit 4 will be described. As described above, the first control valve unit 4 includes the switching valve 31, the superheat degree control valve 32, and the check valve 33. In addition, since a general two-way solenoid valve can be used for the switching valve 31 of this embodiment, and a general mechanical valve can be used for the check valve 33, the superheat degree control valve is used here. The configuration and operation of 32 will be described.

  3 and 4 are cross-sectional views showing a specific configuration and operation of the superheat degree control valve. FIG. 3 shows a closed state of the superheat degree control valve 32, and FIG. 4 shows a opened state of the superheat degree control valve 32. In the following description, for the sake of convenience, the positional relationship between the structures may be expressed based on the illustrated state.

  As shown in FIG. 3, the superheat control valve 32 is configured by housing a main valve 52 and a pilot valve 54 coaxially in a bottomed cylindrical body 50. The body 50 is formed by cutting a metal material. An inlet port 56 for introducing a high-pressure refrigerant is provided on one side of the body 50, and an outlet port 58 for extracting a low-pressure refrigerant is provided on the other side. Is provided. The upper end opening of the body 50 is sealed with a disk-shaped sealing member 59. The sealing member 59 is crimped and joined to the body 50 with an O-ring 57 for sealing interposed therebetween, and the leakage of the refrigerant through the gap between the sealing member 59 and the body 50 is reliably prevented. The A circular boss-shaped partition wall 60 protruding upward is provided at the center of the body 50. The partition wall 60 partitions the inside of the body 50 into a high pressure side pressure chamber 62 and a low pressure side pressure chamber 64. The pressure chamber 62 communicates with the inlet port 56, and the pressure chamber 64 communicates with the outlet port 58.

  A main valve hole 66 is formed by an annular inner peripheral portion of the partition wall 60, and a main valve seat 68 is formed by an upstream opening end portion thereof. A stepped cylindrical valve driver 70 is disposed in the pressure chamber 62. A main valve body 71 that is attached to and detached from the main valve seat 68 to open and close the main valve 52 is integrally provided at a lower portion of the valve driver 70. A plurality of legs 72 are extended downward from the vicinity of the outer peripheral portion of the lower end surface of the valve driver 70 (only one is shown in the figure), and slides on the inner peripheral surface of the main valve hole 66. Supported as possible.

  On the other hand, a flange portion 74 extending outward in the radial direction is provided at the upper end portion of the valve driver 70 and is slidably supported on the inner peripheral surface of the body 50. A sealing O-ring 76 is fitted on the outer peripheral surface of the flange portion 74. The flange portion 74 partitions the pressure chamber 62 into a high pressure chamber 78 and a back pressure chamber 80. A power element 82 is provided to seal the upper end opening of the valve driver 70. The power element 82 senses the temperature and pressure of the refrigerant introduced from the inlet port 56 and drives the pilot valve 54 and the main valve 52 to open and close.

  In addition, the flange portion 74 is provided with a small-section orifice 84 (functioning as a “leak passage”) that allows the high-pressure chamber 78 and the back-pressure chamber 80 to communicate with each other. A passage connecting the high pressure chamber 78 and the pressure chamber 64 via the main valve 52 constitutes a “main passage” in the superheat degree control valve 32, and connecting the high pressure chamber 78 and the pressure chamber 64 via the pilot valve 54. The passage constitutes a “sub-passage” in the superheat degree control valve 32.

  A partition wall 86 extending inward in the radial direction is provided at the center inside the valve driver 70. The partition wall 86 partitions the back pressure chamber 80 and the pressure chamber 64, and a pilot valve hole 88 is formed by an annular inner peripheral portion thereof. A pilot valve seat 90 is formed by the opening end of the pilot valve hole 88 on the back pressure chamber 80 side. A pilot valve body 92 is disposed in the back pressure chamber 80, and the pilot valve body 92 is attached to and detached from the pilot valve seat 90 to open and close the pilot valve 54. A circular boss-shaped partition wall 93 extends downward from the lower end opening of the valve driver 70, and a space surrounded by the partition wall 93 and the partition wall 86 forms a pressure chamber 94. Thus, by extending the partition wall 93 downward, the downstream pressure Pout is reliably introduced into the pressure chamber 94 regardless of the position of the valve driver 70.

  A ring-shaped adjusting member 96 is press-fitted into the lower end opening of the pressure chamber 94, and a bottomed cylindrical actuating rod 98 is provided in the pressure chamber 94. One end of the operating rod 98 passes through the pilot valve hole 88 and is connected to the pilot valve body 92. That is, an insertion hole 99 is formed in the lower half portion of the pilot valve body 92 along the axial direction, and the upper half portion of the operation rod 98 is connected so as to be inserted. A communication groove 97 for circulating the refrigerant in the pressure chamber 94 is formed in the outer peripheral portion of the bottom portion of the operating rod 98. A spring 102 that biases the pilot valve body 92 in the valve opening direction via the operation rod 98 is interposed between the bottom of the operation rod 98 and the adjustment member 96. The load of the spring 102 is adjusted by the press-fitting amount of the adjusting member 96.

  The pilot valve body 92 has a stepped columnar shape that gradually decreases in diameter downward, and a lower end portion of the pilot valve body 92 is formed in a tapered shape, and is attached to and detached from the pilot valve seat 90. An intermediate portion in the axial direction of the pilot valve body 92 is slidably supported on the inner peripheral surface of the upper end portion of the valve drive body 70, and a plurality of communication grooves 104 (only one is shown in the figure) formed on the outer peripheral surface. The pilot valve hole 88 and the back pressure chamber 80 are communicated with each other. The pilot valve body 92 is connected to the power element 82 at the disc-shaped bottom.

  The power element 82 includes a hollow housing 106 and a diaphragm 108 (corresponding to a “pressure-sensitive member”) disposed so as to partition the inside of the housing 106 into a sealed space S1 and an open space S2. Yes. The housing 106 includes an upper housing 110 and a lower housing 112. The diaphragm 108 is made of a thin metal plate such as stainless steel. The power element 82 is formed by performing TIG welding or the like along the outer periphery of the joint portion with the diaphragm 108 sandwiched between the upper housing 110 and the lower housing 112. The power element 82 is fixed to the valve driver 70 such that the outer peripheral portion thereof is crimped to the upper end portion of the flange portion 74. Between the power element 82 and the sealing member 59, a spring 113 (functioning as an “urging member”) that biases the valve driver 70 in the valve closing direction via the housing 106 is interposed.

  The sealed space S1 constitutes a temperature-sensitive room, and after filling the upper housing 110 with a reference gas or the like for maintaining a reference pressure, the hole provided at the center of the upper surface is sealed with a ball-shaped sealing body 114. It is sealed by doing. In the present embodiment, a mixed gas of a refrigerant gas (HFC-134a) circulating in the refrigeration cycle and nitrogen gas is used as the reference gas. In the modified example, the same type of gas as the refrigerant gas circulating in the refrigeration cycle may be used as the reference gas. The upper end surface of the bottom portion of the pilot valve body 92 is in contact with the lower surface of the diaphragm 108. An opening is provided in the lower end surface of the lower housing 112, and the back pressure chamber 80 and the open space S2 are communicated with each other. For this reason, the intermediate pressure Pp of the back pressure chamber 80 is applied to the lower surface of the diaphragm 108.

  In such a configuration, the refrigerant having the upstream pressure Pin introduced via the inlet port 56 is decompressed and expanded on the one hand through the main valve 52 to become the downstream pressure Pout, and on the other hand through the orifice 84 to the back pressure chamber 80. Becomes the intermediate pressure Pp, and reaches the downstream pressure Pout through the pilot valve 54. The intermediate pressure Pp varies depending on the open / close state of the pilot valve 54.

  Here, the power element 82 senses the temperature and pressure of the refrigerant in the back pressure chamber 80, and operates so that the degree of superheat of the refrigerant introduced through the inlet port 56 approaches a set value (for example, 5 deg). Adjust the opening of the section. That is, the power element 82 operates so that the superheat degree on the inlet side of the superheat degree control valve 32 (that is, the outlet side of the outdoor heat exchanger 5) during the heating operation becomes the set superheat degree SH. Adjust the opening. That is, the valve driver 70 is based on the force in the valve opening direction due to the differential pressure (Pin−Pp) between the upstream pressure Pin and the intermediate pressure Pp, and the differential pressure (Pp−Pout) between the intermediate pressure Pp and the downstream pressure Pout. It stops at a position where the force in the valve closing direction and the biasing force in the valve closing direction by the spring 113 are balanced. In balance of the force, the intermediate pressure Pp changes according to the open / close state of the pilot valve 54 by the operation of the power element 82. The pressure in the reference pressure chamber of the power element 82 changes corresponding to the degree of superheat of the refrigerant introduced from the inlet port 56. Thereby, the opening degree of the pilot valve 54 changes so that the superheat degree of the refrigerant introduced from the inlet port 56 approaches the set superheat degree SH, and the opening degree of the main valve 52 is adjusted.

  That is, in the control state of the superheat degree as shown in FIG. 4, when the upstream superheat degree becomes larger than the set superheat degree SH, the power element 82 senses a high temperature and operates in the valve closing direction of the pilot valve 54. As a result, the valve opening degree of the pilot valve 54 becomes small, so that the intermediate pressure Pp increases, and the valve driver 70 operates in the valve closing direction. As a result, since the upstream pressure Pin increases, the amount of heat exchange on the upstream side decreases, and the degree of superheat decreases. Specifically, since the evaporation pressure Po of the outdoor heat exchanger 5 shown in FIG. 2 (B) increases, the temperature difference from the outside air decreases, and the evaporation amount decreases. Thereby, the degree of superheat on the outlet side of the outdoor heat exchanger 5 is reduced.

  On the other hand, when the superheat degree becomes smaller than the set superheat degree SH, the power element 82 senses the low temperature and operates in the valve opening direction of the pilot valve 54. As a result, the valve opening of the pilot valve 54 increases, so that the intermediate pressure Pp decreases, and the valve driver 70 operates in the valve opening direction. As a result, the upstream pressure Pin decreases, so the amount of heat exchange on the upstream side increases and the degree of superheat increases. Specifically, since the evaporation pressure Po of the outdoor heat exchanger 5 shown in FIG. 2 (B) decreases, the temperature difference from the outside air increases, and the amount of evaporation increases. Thereby, the degree of superheat on the outlet side of the outdoor heat exchanger 5 increases. In this way, the superheat degree is maintained at the set superheat degree SH.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The vehicle air conditioning apparatus according to the present embodiment is the same as that of the first embodiment except that the configuration of the superheat degree control valve is different. For this reason, about the component similar to 1st Embodiment, the same code | symbol is attached | subjected etc., and the description is abbreviate | omitted suitably. 5-8 is sectional drawing showing the structure and operation | movement of the superheat degree control valve which concern on 2nd Embodiment. 5 shows the closed state of the main valve, FIG. 6 shows the opening control state of the main valve, FIG. 7 shows the fully opened state of the main valve, and FIG. 8 shows the closed state of the check valve. .

  The superheat degree control valve 232 of this embodiment has a function in which the superheat degree control valve 32 and the check valve 33 shown in FIG. As shown in FIG. 5, the superheat degree control valve 232 is configured by coaxially housing a main valve 252 and a pilot valve 254 in a bottomed cylindrical body 250, and the main valve 252 also functions as a check valve. To do. The power element 82 is disposed not in the upstream pressure chamber 62 but in the downstream pressure chamber 64. The power element 82 operates by sensing the temperature and pressure of the refrigerant led out from the outlet port 58.

  The upper end opening of the body 250 is sealed by press-fitting a disk-shaped sealing member 251. A main valve hole 66 is formed by an inner peripheral portion of the partition wall 60 provided in the body 50, a main valve seat 68 is formed by an upstream opening end portion thereof, and a sub valve seat 268 is formed by a downstream opening end portion thereof. ing. A bottomed cylindrical sealing member 259 is provided so as to seal the lower end opening of the body 250. The sealing member 259 extends upward over the lower half of the body 250, and a guide portion 260 is formed by the inner peripheral surface thereof. The inside of the sealing member 259 communicates with the outlet port 58.

  The valve driver 270 includes a stepped cylindrical main body 271, a main valve body 272 provided at the upper end of the main body 271, and a partition member 273 provided at the lower end of the main body 271. The partition member 273 partitions the pressure chamber 64 into a back pressure chamber 80 and a low pressure chamber 275. A power element 82 is provided so as to seal the lower end opening of the valve driver 270. The valve driver 270 operates in the opening / closing direction of the valve portion such that the outer peripheral surface of the partition member 273 slides on the guide portion 260. An O-ring 76 is interposed between the outer peripheral surface of the partition member 273 and the guide portion 260.

  The main valve body 272 has a stepped cylindrical shape, and its lower half is press-fitted into the main body 271. The main valve body 272 is disposed in the pressure chamber 62 and is attached to and detached from the main valve seat 68 to open and close the main valve 252. The partition member 273 has a large-diameter cylindrical shape and is screwed and fixed to the lower portion of the main body 271. An O-ring 274 for sealing is interposed between the main body 271 and the partition member 273. A valve member 276 made of a ring-shaped elastic body (rubber in this embodiment) is fitted to the center of the upper surface of the partition member 273. The valve member 276 constitutes a valve body and is attached to and detached from the sub valve seat 268 from the pressure chamber 64 side to block the internal passage. That is, the valve driver 270 also functions as a check valve.

  The partition member 273 is formed with a communication passage 278 that constitutes a part of the back pressure chamber 80 and an orifice 84 (leak passage) that connects the communication passage 278 and the outlet port 58. A passage connecting the pressure chamber 62 and the low pressure chamber 275 via the main valve 252 constitutes a “main passage” in the superheat degree control valve 232, and connecting the pressure chamber 62 and the low pressure chamber 275 via the pilot valve 254. The passage constitutes a “sub-passage” in the superheat control valve 232.

  A pilot valve hole 88 having a slightly reduced diameter inward in the radial direction is provided at the lower end of the internal passage 279 of the valve driver 270. A pilot valve seat 90 is formed by the opening end of the pilot valve hole 88 on the back pressure chamber 80 side. A pilot valve body 280 is disposed in the back pressure chamber 80, and the pilot valve body 280 opens and closes the pilot valve seat 90 to open and close the pilot valve 254.

  The pilot valve body 280 is fitted with a valve member 282 made of a ring-shaped elastic body (rubber in the present embodiment) on the enlarged diameter portion of the upper end of the stepped cylindrical body 281, and the valve member 282 is connected to the body 281. The shaft member 283 is assembled so as to be sandwiched between them. The shaft member 283 is inserted into the main body 281 and fixed to the main body 281 by crimping one end thereof. The valve member 282 is locked by the other end of the shaft member 283 to prevent the valve member 282 from dropping from the main body 281.

  A bottomed stepped cylindrical transmission member 285 is disposed between the pilot valve body 280 and the diaphragm 108. The bottom of the transmission member 285 abuts against the diaphragm 108, and a guide hole 286 that supports the lower half of the pilot valve body 280 in a slidable manner is formed in the inside thereof. The pilot valve body 280 is locked to the upper end surface of the transmission member 285, so that its downward displacement is restricted.

  Between the pilot valve body 280 and the transmission member 285, a spring 288 (functioning as an “urging member”) that biases the pilot valve body 280 in the valve closing direction is interposed. On the other hand, a spring 290 (which functions as an “urging member”) for biasing the transmission member 285 in the valve opening direction of the pilot valve 254 is interposed between the transmission member 285 and the valve driver 270. Between the power element 82 and the sealing member 259, a spring 113 (functioning as an “urging member”) that urges the valve driver 270 in the valve opening direction of the main valve 252 via the housing 106 is interposed. Has been.

  In such a configuration, the refrigerant having the upstream pressure Pin introduced through the inlet port 56 is decompressed and expanded on the one hand via the main valve 252 to become the downstream pressure Pout, and on the other hand, the internal passage 279 and the pilot valve 254 are connected. After that, the intermediate pressure Pp is reached in the back pressure chamber 80, and the downstream pressure Pout is reached via the orifice 84. The intermediate pressure Pp varies depending on the open / close state of the pilot valve 254.

  In the present embodiment, the power element 82 senses the temperature and pressure of the refrigerant in the back pressure chamber 80, and operates so that the degree of superheat of the refrigerant derived through the outlet port 58 approaches a set value (for example, 5 deg). Adjust the opening of the valve. That is, the power element 82 operates so that the superheat degree on the outlet side of the superheat degree control valve 232 becomes the set superheat degree SH during the heating operation, and adjusts the opening degree of the main valve 252. As shown in FIG. 2B, the superheat degree on the outlet side of the superheat degree control valve 232 is substantially equal to the superheat degree on the inlet side. While adjusting the degree, the degree of superheat on the inlet side of the superheat degree control valve 232, that is, on the outlet side of the outdoor heat exchanger 5, is substantially adjusted.

  The valve driver 270 is based on the force in the valve closing direction due to the differential pressure (Pin−Pout) between the upstream pressure Pin and the downstream pressure Pout and the differential pressure (Pp−Pout) between the intermediate pressure Pp and the downstream pressure Pout. It stops at a position where the force in the valve opening direction and the biasing force in the valve opening direction by the spring 113 are balanced. In balance of the force, the intermediate pressure Pp changes according to the open / close state of the pilot valve 254 by the operation of the power element 82. The pressure in the reference pressure chamber of the power element 82 changes corresponding to the degree of superheat of the downstream refrigerant. Thereby, the opening degree of the pilot valve 254 changes so that the superheat degree of the refrigerant derived from the outlet port 58 approaches the set superheat degree SH, and the opening degree of the main valve 252 is adjusted.

  That is, in the superheat degree control state as shown in FIG. 6, when the downstream superheat degree becomes larger than the set superheat degree SH, the power element 82 senses a high temperature and operates in the valve closing direction of the pilot valve 254. As a result, the valve opening degree of the pilot valve 54 becomes small, so that the intermediate pressure Pp decreases, and the valve driver 270 operates in the valve closing direction of the main valve 252. As a result, since the upstream pressure Pin increases, the amount of heat exchange on the upstream side decreases, and the degree of superheat decreases.

  Conversely, when the degree of superheat becomes smaller than the set degree of superheat SH, the power element 82 senses the low temperature and operates in the valve opening direction of the pilot valve 254. As a result, the valve opening of the pilot valve 54 increases, so that the intermediate pressure Pp increases, and the valve driver 270 operates in the valve opening direction. As a result, the upstream pressure Pin decreases, so the amount of heat exchange on the upstream side increases and the degree of superheat increases. In this way, the superheat degree is maintained at the set superheat degree SH.

  As shown in FIG. 7, when the valve driver 270 operates in the valve opening direction of the main valve 252, the outlet port 58 and the communication path 278 rise to a position where they communicate with each other via the outer periphery of the valve driver 270. The opening area of the outer peripheral portion is considerably larger than the flow path cross section of the orifice 84. That is, since the rate of decrease of the pressure in the back pressure chamber 80 is increased, the force in the valve opening direction of the valve driver 270 does not increase any more. For this reason, in a state where the upstream pressure Pin is higher than the downstream pressure Pout, the valve driver 270 does not operate further in the valve opening direction of the main valve 252. For this reason, the state shown in the figure is the fully opened state of the main valve 252.

  On the other hand, if the downstream pressure Pout is higher than the upstream pressure Pin as in the state shown in FIG. 2D, the differential pressure between the intermediate pressure Pp and the upstream pressure Pin is shown in FIG. Since a force due to (Pp-Pin) is applied, the valve member 276 is seated on the sub valve seat 268 and the check valve is closed. For this reason, the reverse flow of the refrigerant from the outlet port 58 to the inlet port 56 is prevented.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The vehicle air conditioning apparatus according to the present embodiment is the same as that of the first embodiment except that a switching valve, a superheat degree control valve, and a check valve are integrally configured as a first control valve unit. For this reason, about the component similar to 1st Embodiment, the same code | symbol is attached | subjected etc., and the description is abbreviate | omitted suitably. FIG. 9 is a cross-sectional view illustrating a specific configuration of the first control valve unit according to the third embodiment.

  The first control valve unit 304 of this embodiment is integrated so that the switching valve 31, the superheat degree control valve 332, and the check valve 33 have a common body 350. The body 350 is provided with an inlet port 354 connected to the discharge chamber of the compressor 2, an inlet / outlet port 356 connected to the inlet / outlet of the outdoor heat exchanger 5, and an outlet port 58 connected to the inlet of the accumulator 8. A stepped cylindrical valve seat forming member 352 is press-fitted into the center of the body 350. A valve hole 366 is formed by the inner periphery of the valve seat forming member 352, a main valve seat 68 is formed at the upper end opening thereof, and a sub valve seat 268 is provided at the lower end opening. The valve hole 366 communicates with the inlet / outlet port 356 on the main valve seat 68 side, and communicates with the outlet port 58 on the sub valve seat 268 side. An O-ring 368 for sealing is provided between the valve seat forming member 352 and the body 350.

  The superheat degree control valve 332 has a structure in which the main valve 370 approximates the main valve 52 in FIG. 3, and the pilot valve 372 has a structure approximate to the pilot valve 254 in FIG. The valve drive body 374 has a double structure in which the main body and the partition member are screwed together via an O-ring 274, and the lower end portion thereof constitutes the main valve body 376. The main valve body 376 is constituted by a valve member made of an elastic body, and is attached to and detached from the main valve seat 68 to open and close the main valve 370. The valve driver 374 is provided with a pilot passage along its axis, a pilot valve hole 88 is formed at the upstream end of the pilot passage, and a pilot valve seat 90 is formed at the upstream opening end. .

  The pilot valve body 380 has a stepped columnar shape, and the end surface on the large diameter side abuts against the diaphragm 108 of the power element 82. A valve member made of an elastic body is fitted on the opposite side of the pilot valve body 380 from the diaphragm 108. The pilot valve body 380 opens and closes the pilot valve 372 by attaching / detaching the valve member to / from the pilot valve seat 90. . A spring 290 that biases the pilot valve body 380 in the valve opening direction of the pilot valve 372 is interposed between the valve drive body 374 and the pilot valve body 380.

  The check valve 33 has a bottomed cylindrical valve body 382 disposed in the pressure chamber 64. A ring-shaped valve member 384 made of an elastic body (rubber in the present embodiment) is fitted to the outer peripheral portion of the bottom of the valve body 382, and the valve member 384 is non-returned by being attached to and detached from the sub valve seat 268. The valve 33 is opened and closed. A plurality of legs 385 extend upward from the bottom of the valve body 382 and are slidably supported on the inner peripheral surface of the valve seat forming member 352. Further, the lower half portion of the valve body 382 is slidably supported by a circular boss-shaped guide portion 386 provided in the body 350. That is, the valve body 382 operates in the opening / closing direction of the valve portion while being supported at the top and bottom. A spring 388 that biases the valve body 382 in the valve closing direction is interposed between the valve body 382 and the body 350. A communication hole 389 that communicates the inside and the outside is formed in the lower half of the valve body 382 so that the refrigerant can be introduced into the back pressure chamber of the valve body 382.

  The switching valve 31 is configured as a pilot-actuated on / off solenoid valve that opens and closes a valve portion depending on the presence or absence of energization. The switching valve 31 is configured by assembling a valve body 401 and a solenoid 402. The valve body 401 is configured such that the main valve 405 and the pilot valve 406 are coaxially accommodated with respect to the body 350. A main valve hole 420 that communicates the inlet port 354 and the high-pressure chamber 78 is formed inside the body 350, and a main valve seat 422 is formed by an upstream opening end portion thereof.

  In the pressure chamber 357 on the upstream side (inlet port 354 side) of the main valve hole 420, a stepped cylindrical valve driver 424 is disposed. A valve body 425 provided at the tip of the valve driver 424 attaches / detaches to / from the main valve seat 422 to open / close the main valve 405. The valve body 425 is made of an elastic body (rubber in this embodiment). A plurality of legs 432 extend from the vicinity of the outer peripheral edge of the distal end portion of the valve driver 424 (only one is shown in the figure) and is slidably supported by the inner peripheral surface of the main valve hole 420. ing.

  On the other hand, a flange portion 434 extending outward in the radial direction is provided at the rear end portion (right end portion in the figure) of the valve driver 424 and is slidably supported on the inner peripheral surface of the body 350. An O-ring 436 for sealing is fitted on the outer peripheral surface of the flange portion 434. The flange portion 434 partitions the pressure chamber 357 into a high pressure chamber 438 and a back pressure chamber 440. A plurality of leg portions 442 extend rearward from the flange portion 434 (only one is shown in the figure) and extend to the inside of the solenoid 402.

  A passage connecting the high pressure chamber 438 and the high pressure chamber 78 via the main valve 405 constitutes a “main passage” in the switching valve 31, and a passage connecting the high pressure chamber 438 and the high pressure chamber 78 via the pilot valve 406. A “sub-passage” in the switching valve 31 is configured.

  A pilot passage 444 that connects the back pressure chamber 440 and the high pressure chamber 78 in the axial direction is formed in the center of the valve driver 424, and the end of the pilot passage 444 on the back pressure chamber 440 side is a pilot valve hole. 446 is formed. A valve seat 449 is formed by the upstream opening end of the pilot valve hole 446. As will be described later, a pilot valve body 450 constituting the pilot valve 406 opens and closes the pilot valve hole 446 by being attached to and detached from the valve seat 449 according to the control state.

  The pilot valve body 450 has a long main body and is press-fitted and fixed to a first plunger 471 described later. A ring-shaped valve member 451 made of an elastic body (rubber in this embodiment) is fitted to the tip of the pilot valve body 450. The pilot valve body 450 is disposed in the back pressure chamber 440 and is attached to and detached from the valve seat 449 to open and close the pilot valve 406. A leak passage 460 having a small cross section is formed in the side portion of the valve driver 424, and the high pressure chamber 438 and the back pressure chamber 440 are communicated with each other. A filter 455 is provided at the side of the valve driver 424 so as to surround the leak passage 460 from the outside, and prevents foreign matter from entering the back pressure chamber 440.

  In the above configuration, the pressure Pd introduced from the inlet port 354 becomes the intermediate pressure Pp2 in the back pressure chamber 440 through the leak passage 460. The intermediate pressure Pp2 varies depending on the open / close state of the pilot valve 406.

  On the other hand, the solenoid 402 has a bottomed cylindrical sleeve 470 attached to seal the right end opening of the body 350. A first plunger 471 (corresponding to “first movable iron core”) and a second plunger 472 (corresponding to “second movable iron core”) are accommodated in the sleeve 470 so as to face each other in the axial direction. Has been. A bobbin 473 is provided on the outer periphery of the sleeve 470, and an electromagnetic coil 474 is wound around the bobbin 473. A case 476 is provided so as to cover the electromagnetic coil 474 from the outside. The sleeve 470 penetrates the case 476 in the axial direction. A current-carrying harness 478 is drawn from the electromagnetic coil 474.

  The first plunger 471 has a cylindrical shape, and is provided with a plurality of slits 481 (one of which is shown in the figure) extending in the axial direction on the outer periphery thereof. The leg portion 442 of the valve driver 424 described above extends rightward through the slit 481. The right half of the pilot valve body 450 is press-fitted along the axis of the first plunger 471. That is, the pilot valve body 450 operates integrally with the first plunger 471.

  The second plunger 472 has a cylindrical shape, and a partition wall is provided at the center of the inside thereof. The second plunger 472 contacts and supports the right end surface of the leg portion 442 at the left end surface thereof. Between the first plunger 471 and the second plunger 472, a spring 484 (corresponding to an “urging member”) that biases the pilot valve body 450 in the valve closing direction via the first plunger 471 is interposed. ing. Between the second plunger 472 and the sleeve 470, a spring 486 for biasing the valve driver 424 in the valve closing direction via the second plunger 472 is interposed. That is, the valve driver 424 can operate integrally with the second plunger 472.

  Next, the operation of the first control valve unit 304 will be described. 10-12 is explanatory drawing showing operation | movement of a 1st control valve unit. FIG. 10 shows a control state in which the solenoid 402 is turned on. FIGS. 11 and 12 and FIG. 9 described above show a state where the solenoid 402 is turned off. FIG. 10 corresponds to FIG. FIGS. 9 and 11 correspond to FIGS. 2B and 2C and show a state in which the opening of the main valve is different from each other. FIG. 12 corresponds to FIG.

  That is, during the cooling operation, as shown in FIG. 10, the solenoid 402 is turned on (energized state) in the switching valve 31, so that a suction force acts between the first plunger 471 and the second plunger 472 by the solenoid force. Therefore, the pilot valve body 450 is urged in the valve opening direction, and the pilot valve 406 is opened. As a result, the intermediate pressure Pp2 in the back pressure chamber 440 decreases, so that the differential pressure (Pd−Pp2) acts on the valve driver 424 greatly, and the valve driver 424 is driven in the valve opening direction. For this reason, the main valve 405 is opened. That is, the switching valve 31 is opened.

  As a result, the high-pressure refrigerant with the discharge pressure Pd is introduced into the high-pressure chamber 78 through the main valve hole 420 and led out to the outdoor heat exchanger 5 side through the inlet / outlet port 356. At this time, high-pressure refrigerant is introduced into the back pressure chamber 80 via the orifice 84 in the superheat degree control valve 332. On the other hand, since the refrigerant of the discharge pressure Pd discharged from the compressor 2 is high temperature, the power element 82 drives the pilot valve body 380 in the valve closing direction, and the pilot valve 372 is also maintained in the valve closed state. For this reason, the intermediate pressure Pp is increased, the valve driver 374 is driven in the valve closing direction, and the main valve 370 is in the valve closing state. That is, the superheat degree control valve 332 is closed. The check valve 33 is closed by the urging force of the spring 388 because substantially no differential pressure acts on the valve body 382. In this way, the refrigerant circulation shown in FIG. 2A is realized.

  During the heating operation, as shown in FIGS. 11 and 9, the solenoid 402 is turned off (non-energized state) in the switching valve 31, so that the pilot valve body 450 operates in the valve closing direction by the urging force of the spring 484, The pilot valve 406 is closed. As a result, the intermediate pressure Pp2 in the back pressure chamber 440 is maintained high, and the valve driver 424 is biased in the valve closing direction by the spring 486, so that the main valve 405 is also closed. That is, the switching valve 31 maintains a closed state.

  On the other hand, since the refrigerant having the evaporation pressure Po derived from the outdoor heat exchanger 5 is introduced through the inlet / outlet port 356, the superheat degree control valve 332 operates so that the superheat degree approaches the set superheat degree SH. That is, the refrigerant having the evaporation pressure Po is introduced into the back pressure chamber 80 through the orifice 84, and the power element 82 operates by sensing the temperature and pressure of the refrigerant. At this time, since the pilot valve 372 opens, the intermediate pressure Pp decreases. For this reason, the differential pressure (Po-Pp) acts on the valve drive body 374 so that the valve drive body 374 is driven in the valve opening direction. For this reason, the main valve 370 is opened. The opening degree of the main valve 370 at this time autonomously changes so that the degree of superheat on the outlet side of the outdoor heat exchanger 5 approaches the set superheat degree SH. Further, when the main valve 370 is opened as described above, a large differential pressure acts on the valve body 382, and the check valve 33 is opened. In this way, the refrigerant circulation shown in FIG. 2B is realized.

  Further, since the solenoid 402 is turned off during the specific heating operation, the switching valve 31 maintains the closed state. On the other hand, the refrigerant having the evaporation pressure Po derived from the outdoor heat exchanger 5 is introduced through the inlet / outlet port 356. However, in this case, as shown in FIG. 2C, the first refrigerant circulation passage is blocked, and all the refrigerant derived from the indoor condenser 3 passes through the outdoor heat exchanger 5, The amount of heat exchange in the outdoor heat exchanger 5 is increased, and the evaporation pressure Po is considerably reduced. For this reason, the power element 82 senses the low temperature, and the pilot valve 372 opens greatly, so that the intermediate pressure Pp becomes considerably low. As a result, the main valve 370 is almost fully opened. Further, when the main valve 370 is opened as described above, a differential pressure acts on the valve body 382, and the check valve 33 is also opened. In this way, the refrigerant circulation shown in FIG. 2C is realized.

  During the special air conditioning operation, as shown in FIG. 12, the solenoid 402 is turned off, so that the switching valve 31 maintains the closed state. On the other hand, as shown in FIG. 2D, the second refrigerant circulation passage is blocked and all the refrigerant led out from the indoor condenser 3 passes through the evaporator 7, so that the outdoor heat exchanger 5 The pressure at becomes considerably low. At this time, since the refrigerant is not introduced through the inlet / outlet port 356, the valve driver 374 is driven in the valve closing direction by the urging force of the spring 113, and the main valve 370 is closed. On the other hand, reverse pressure is applied to the valve body 382 and the check valve 33 is closed, so that backflow of the refrigerant is prevented. In this way, the refrigerant circulation shown in FIG. 2D is realized.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. This embodiment is the same as the third embodiment except that the configuration of the first control valve unit is slightly different. For this reason, about the component similar to 3rd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted suitably. 13 and 14 are cross-sectional views showing the configuration and operation of the first control valve unit according to the fourth embodiment. FIG. 13 shows a state where the solenoid 402 is turned on in the switching valve 31 and corresponds to FIG. FIG. 14 shows a state immediately after the solenoid 402 is turned off in the switching valve 31.

  As shown in FIG. 13, the first control valve unit 404 of the present embodiment is capable of opening and closing the second refrigerant circulation passage promptly before the main valve 370 is opened when the switching valve 31 is closed. A valve 410 is provided. That is, a valve hole 412 that communicates the inside and the outside is provided in the side surface near the upper end of the valve seat forming member 352, and the valve seat 413 is formed by the outer opening end portion thereof. On the other hand, an annular valve body 414 is provided so as to surround the upper end portion of the valve seat forming member 352. The valve body 414 is fitted with a valve member 416 made of an elastic body at a position facing the valve hole 412, and is attached to and detached from the valve seat 413 from the outside to open and close the on-off valve 410. A ring-shaped spring receiving member 418 is fitted in the vicinity of the inlet / outlet port 356 in the body 350, and a spring 419 that biases the valve body 414 in the valve closing direction between the spring receiving member 418 and the valve body 414. Is intervening. On the other hand, a drive unit 421 that drives the on-off valve 410 in the valve opening direction is formed at the tip of the valve driver 424 in the switching valve 31.

  In such a configuration, when the switching valve 31 is closed, the drive unit 421 presses the valve body 414 in the valve opening direction as shown in FIG. As a result, the valve member 416 is separated from the valve seat 413 to open the on-off valve 410. That is, even if the on-off valve 410 is not provided, the superheat degree control valve 332 is opened when the refrigerant is introduced from the outdoor heat exchanger 5, but the refrigerant circulation is changed and the pressure is introduced. There is a time lag. According to the present embodiment, the second refrigerant circulation passage can be quickly opened simultaneously with the closing of the switching valve 31, and this time lag can be compensated for, and the refrigerant flow can be changed quickly.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the technical idea of the present invention. Nor.

  In the above-described embodiment, an example in which the vehicle air conditioning apparatus according to the present invention is applied to an electric vehicle has been described. However, the present invention can be provided to an automobile equipped with an internal combustion engine or a hybrid automobile equipped with an internal combustion engine and an electric motor. Needless to say. In the above-described embodiment, an example in which an electric compressor is employed as the compressor 2 has been described. However, a variable capacity compressor that performs variable capacity using the rotation of the engine may be employed.

  In the superheat degree control valves 32, 232, and 332 of the above-described embodiment, an example is shown in which a diaphragm is used as a pressure-sensitive member that senses the pressure and temperature of the refrigerant. As the pressure sensitive member, a member that senses pressure and expands and contracts, such as a bellows, can also be used. However, in order to realize a compact supercooling degree control valve, it is preferable to employ a diaphragm which is a thin film pressure sensitive member.

  In the said embodiment, the example which provides an indoor condenser as an auxiliary condenser was shown. In a modification, the auxiliary condenser may be configured as a heat exchanger provided separately from the outdoor heat exchanger. The heat exchanger may be disposed outside the passenger compartment, for example, and may perform heat exchange using engine coolant. Specifically, a heat exchanger is provided between the compressor 2 and the second control valve unit 6 in FIG. 1, while a radiator is disposed in the duct 10, and the heat exchanger and the radiator are connected with cooling water. You may connect in the circulation circuit of. A pump for pumping cooling water may be provided in the circulation circuit. If it does in this way, heat exchange can be performed between the hot refrigerant | coolant which goes to the 2nd control valve unit 6 from the compressor 2, and the cooling water which circulates through a circulation circuit. Even in such a configuration, the refrigerant discharged from the compressor 2 can be condensed by the heat exchanger and supplied to the second control valve unit 6.

  DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner, 2 Compressor, 3 Indoor condenser, 4 1st control valve unit, 5 Outdoor heat exchanger, 6 2nd control valve unit, 7 Evaporator, 8 Accumulator, 31 Switching valve, 32 Superheat degree control Valve, 33 Check valve, 41 Supercooling control valve, 42 Proportional valve, 43 Supercooling control valve, 44 Check valve, 50 Body, 52 Main valve, 54 Pilot valve, 56 Inlet port, 58 Outlet port, 66 Main valve hole, 68 Main valve seat, 70 Valve drive body, 71 Main valve body, 82 Power element, 84 Orifice, 88 Pilot valve hole, 90 Pilot valve seat, 92 Pilot valve body, 100 Control unit, 232 Superheat degree control valve , 250 body, 252 main valve, 254 pilot valve, 268 auxiliary valve seat, 270 valve driver, 2 DESCRIPTION OF SYMBOLS 1 Main body, 272 Main valve body, 280 Pilot valve body, 304 1st control valve unit, 332 Superheat control valve, 350 Body, 354 Inlet port, 356 Inlet / outlet port, 366 Valve hole, 370 Main valve, 372 Pilot valve, 374 Valve drive body, 376 Main valve body, 380 Pilot valve body, 382 Valve body, 401 Valve body, 402 Solenoid, 404 First control valve unit, 405 Main valve, 406 Pilot valve, 410 Open / close valve, 412 Valve hole, 413 Valve Seat, 414 Valve body, 420 Main valve hole, 422 Main valve seat, 424 Valve drive body, 425 Valve body, 444 Pilot passage, 446 Pilot valve hole, 449 Valve seat, 450 Pilot valve body, 480 Open / close valve, S1 Sealed space , S2 Open space.

Claims (4)

A body provided with an inlet port for introducing the refrigerant from the upstream side, an outlet port for leading the refrigerant to the downstream side, and a main valve hole communicating the inlet port and the outlet port;
A valve drive body including a main valve body that adjusts the valve opening degree by contacting and separating from the main valve hole;
A temperature sensing unit that senses the temperature and pressure of the refrigerant flowing through the internal passage connecting the inlet port and the outlet port, and drives the main valve body to open and close so that the superheat degree of the refrigerant becomes a set superheat degree;
A control valve comprising: A main passage that directly connects the inlet port and the outlet port has the main valve body that opens and closes the main valve hole, and the valve driver separates the main passage and the back pressure chamber. A main valve provided in
A pilot valve body capable of adjusting an opening degree of a sub-passage connecting the inlet port and the outlet port via the back pressure chamber by making contact with and separating from the sub-valve hole, and the pilot valve body is the temperature sensing portion; A pilot valve that generates an opening and closing drive force of the main valve body by being operatively connected to
The control valve according to claim 1, further comprising: A compressor that compresses and discharges the refrigerant;
An outdoor heat exchanger that is arranged outside the passenger compartment and functions as an outdoor condenser that dissipates the refrigerant during cooling operation, while functioning as an outdoor evaporator that evaporates the refrigerant during heating operation;
An indoor evaporator disposed in the passenger compartment to evaporate the refrigerant;
An auxiliary condenser for radiating the refrigerant separately from the outdoor heat exchanger;
A first refrigerant circulation passage capable of circulating so that refrigerant discharged from the compressor during cooling operation and heating operation returns to the compressor via the auxiliary condenser and the indoor evaporator in sequence,
A second refrigerant circulation passage capable of circulating so that refrigerant discharged from the compressor during heating operation returns to the compressor via the auxiliary condenser and the outdoor heat exchanger in turn,
A third refrigerant circulation passage capable of circulating so that the refrigerant discharged from the compressor during the cooling operation returns to the compressor via the outdoor heat exchanger and the indoor evaporator in order,
A first valve that is provided downstream of the auxiliary condenser and adjusts the flow rate of the refrigerant supplied to the indoor evaporator via the first refrigerant circulation passage;
A second valve that is provided on the downstream side of the auxiliary condenser and adjusts the flow rate of the refrigerant supplied to the outdoor heat exchanger via the second refrigerant circulation passage;
Superheat degree which is provided in the second refrigerant circulation passage and adjusts the flow rate of the refrigerant so that the superheat degree on the outlet side of the outdoor heat exchanger when the outdoor heat exchanger functions as an outdoor evaporator becomes a set superheat degree. A control valve;
A vehicle air-conditioning / heating device comprising: The superheat control valve is
A body provided with an inlet port for introducing the refrigerant from the upstream side, an outlet port for leading the refrigerant to the downstream side, and a valve hole communicating the inlet port and the outlet port;
A valve element that adjusts the valve opening by contacting and separating from the valve hole;
A temperature sensing unit that senses the temperature and pressure of the refrigerant introduced from the inlet port, and opens and closes the valve body so that the degree of superheat on the outlet side of the outdoor heat exchanger becomes the set superheat degree; and
The vehicle air conditioning apparatus according to claim 3, further comprising:

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