JP2011245978A - Control valve and air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle, which can secure good dehumidifying performance during heating operation, and to provide a control valve suitable for the air conditioner for the vehicle.SOLUTION: A control valve applied to the air conditioner for the vehicle of some mode has: a first valve having a first valve element opening or closing a first communication passage connecting a first passage and a second passage by coming into contact with and being separated from the first valve element; and a second valve element opening or closing a second communication passage connecting a second passage and a third passage by coming into contact with and being separated from the second valve element. The control valve includes: a second valve connected to the first valve element so as to be able to operate independently the first valve element when the second valve element is in a closed state and so as to be able to operate integrally with the first valve element when the second valve element is in an opened state; and an actuator adjusting opening of the first valve by driving the first valve independently of the second valve when the first valve is in an opened state, and on the other hand, adjusting opening of the second valve by driving integrally the first valve and the second valve when the first valve is closed.

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, when the outdoor heat exchanger functions as an evaporator during heating operation, if the evaporation amount becomes larger than necessary, sufficient liquid refrigerant is supplied to the evaporator in the vehicle interior. May happen. In this case, the heat exchange in the evaporator is substantially not performed, so that the dehumidifying function in the vehicle interior cannot be properly maintained, and problems such as fogging of the window glass may occur. Therefore, the inventor considered that such problems can be solved if the outdoor heat exchanger can function as an evaporator so that an appropriate amount of liquid refrigerant can be supplied to the evaporator in the passenger compartment. .

  One of the objects of the present invention is to provide a vehicle air conditioner that can ensure good dehumidifying performance during heating operation, and a control valve suitable for the vehicle air conditioner.

  In order to solve the above problems, an aspect of the present invention is a control valve that is provided between the first passage, the second passage, and the third passage, and that can control the flow of fluid between the passages. A first valve having a first valve body that opens and closes by opening and closing a first communication passage that connects the first passage and the second passage with the first valve hole, and a second passage that connects the second passage and the third passage. The second communication body has a second valve body that opens and closes by being brought into contact with and separated from the second valve hole. When the second valve body is in a closed state, the first valve body can be independently operated. A second valve connected to the first valve body so that the valve body can be integrated with the first valve body when the valve body is open, and the first valve body when the first valve is opened. The first valve body is driven independently of the second valve body to adjust the opening degree of the first valve, while the first valve body and the second valve body are integrally driven when the first valve is closed. Actuator to adjust the degree , Comprising a.

  Here, the "first valve" and the "second valve" may be those whose valve opening is adjusted to the respective set opening by an actuator. For example, the valve opening degree may be controlled 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. Each valve may be such that the valve opening degree increases as the supply current value increases, and the valve opening degree decreases as the supply current value decreases. Conversely, the valve opening may be reduced as the supply current value increases, and the valve opening may be increased as the supply current value decreases. In this case, the relationship between the supply current value and the valve opening degree may correspond to a linear (primary function) or a curved shape (secondary function). In addition, there may be an inflection point when corresponding in a linear function, but it is preferable to correspond linearly. When each valve is a “proportional valve”, it is sufficient that the valve opening has a tendency to change almost proportionally with respect to the drive amount (for example, the number of pulses of the drive signal or the supply current value), and changes slightly in a curved line. Although a thing or a thing with an inflection point may be sufficient, it is preferable that it changes linearly.

  According to this aspect, when one of the first valve and the second valve is opened, the other is closed, and the first valve and the second valve are not controlled in the open state at the same time. Since the first valve and the second valve are driven by one actuator, it can be realized at low cost. Then, by applying the control valve of this aspect as a composite valve to, for example, a vehicle air conditioner as described below, the flow rate of the refrigerant introduced into the indoor evaporator can be ensured even during heating operation. The humidity function can be properly maintained.

  That is, another aspect of the present invention is a vehicle air conditioner. This device is a compressor that compresses and discharges refrigerant, and an outdoor condenser that is disposed outside the vehicle cabin and functions as an outdoor condenser that dissipates heat during cooling operation, and functions as an outdoor evaporator that evaporates refrigerant during heating operation. Heat exchanger, indoor evaporator placed in the passenger compartment to evaporate the refrigerant, and refrigerant discharged from the compressor during cooling operation and heating operation can be circulated to return to the compressor via the indoor evaporator The first refrigerant circulation passage, the second refrigerant circulation passage capable of circulating the refrigerant discharged from the compressor during the heating operation so as to return to the compressor via the outdoor heat exchanger, and the refrigerant discharged from the compressor during the cooling operation. The third refrigerant circulation passage that can circulate the refrigerant so that it returns to the compressor via the outdoor heat exchanger and the indoor evaporator in order, and the first refrigerant circulation passage, and flows from the compressor to the indoor evaporator Adjust the refrigerant flow rate An adjustment valve whose opening degree is controlled to perform, a first valve which is provided in the second refrigerant circulation passage and whose opening degree is controlled to control the flow rate of the refrigerant flowing from the compressor to the outdoor heat exchanger, A composite valve provided integrally with a second valve provided in the third refrigerant circulation passage and having an opening degree controlled to control the flow rate of the refrigerant flowing from the outdoor heat exchanger to the indoor evaporator; A control unit that controls driving.

  The composite valve is provided between the first passage connected to the discharge side of the compressor, the second passage connected to the outdoor heat exchanger, and the third passage connected to the inlet side of the indoor evaporator. And a first valve having a first valve body that opens and closes a first communication passage connecting the first passage and the second passage by contacting and separating from the first valve hole. The second communication passage connecting the second passage and the third passage has a second valve body that opens and closes by contacting and separating from the second valve hole, and the second valve body is closed when the second valve body is in a closed state. A second valve connected to the first valve body so that the one valve body can be operated independently, and the second valve body can be integrated with the first valve body when the second valve body is in an open state; When the first valve is opened, the first valve body is driven independently of the second valve body to adjust the opening of the first valve, while the first valve body and the second valve body are closed when the first valve is closed. Drive together Comprising an actuator for adjusting the opening of the second valve, the Te. When the control unit drives and controls the actuator to open one of the first valve and the second valve, the control unit closes the other, so that one of the second refrigerant circulation passage and the third refrigerant circulation passage is closed. When allowing the flow and opening the second refrigerant circulation passage, the respective openings of the first valve and the regulating valve of the composite valve are controlled to control the flow of the refrigerant flowing from the compressor to the outdoor heat exchanger and the indoor evaporator. Adjust the flow rate.

  Here, “each valve of the composite valve” and “regulating valve” are valve openings adjusted to the respective set opening degrees by driving of the control unit. For example, the valve opening degree may be controlled 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 varies proportionally according to a control command value. Each valve may be such that the valve opening degree increases as the supply current value increases, and the valve opening degree decreases as the supply current value decreases. Conversely, the valve opening may be reduced as the supply current value increases, and the valve opening may be increased as the supply current value decreases. In this case, the relationship between the supply current value and the valve opening degree may correspond to a linear (primary function) or a curved shape (secondary function). In addition, there may be an inflection point when corresponding in a linear function, but it is preferable to correspond linearly.

  According to this aspect, during the heating operation, the opening degrees of the composite valve (first valve) and the regulating valve are controlled. Thereby, the ratio of the refrigerant flow rate flowing from the compressor to the outdoor heat exchanger (outdoor evaporator) and the indoor evaporator is adjusted. That is, since the evaporation amount in each evaporator can be adjusted, by securing the evaporation amount of the indoor evaporator, the flow rate of the refrigerant introduced into the indoor evaporator can be ensured even during heating operation, The humidity function in the passenger compartment can be properly maintained.

  Yet another aspect of the present invention is a pilot operated control valve capable of controlling the flow of refrigerant from the upstream side to the downstream side. This control valve has a main valve hole that allows the upstream passage and the downstream passage to communicate with each other, and a main valve body that can be adjusted to open and close to the main valve hole. A main valve provided to divide the side passage, the downstream passage, and the back pressure chamber; a pilot valve hole that communicates one of the upstream passage and the downstream passage with the back pressure chamber; A pilot valve having a pilot valve body whose opening degree can be adjusted, and a leak passage having a flow passage cross-sectional area smaller than the pilot valve hole and communicating the back pressure chamber with the other of the upstream passage and the downstream passage A solenoid that includes a first iron core that moves in the axial direction integrally with the pilot valve body, and a second iron core that is disposed opposite to the first iron core with a gap in the axial direction, a main valve body, and a pilot valve body And the main valve by expansion and contraction due to its elastic deformation And an elastic member that allows relative displacement between the pilot valve body and the main valve by elastically deforming the elastic member so as to generate a load that is commensurate with a change in the suction force of the solenoid in the energization control state of the solenoid. Is controlled to the set opening.

  According to this aspect, the elastic member can be deformed to be larger than the change amount of the gap between the first iron core and the second iron core due to the change in the suction force of the solenoid, and the stop position of the main valve body is determined by the elastic deformation amount of the elastic member. Is made to amplify the stroke of the main valve body. For this reason, the amount of displacement in the solenoid can be made relatively small, while the opening of the main valve can be changed greatly. Therefore, a small solenoid can be employed as a drive source. By applying the control valve of this aspect to the above-described regulating valve and composite valve, the valve opening degree of each valve can be controlled to a desired opening degree, and the vehicle air conditioner can be reduced in size and space-saving. Is also possible.

  ADVANTAGE OF THE INVENTION According to this invention, the control valve suitable for the vehicle air conditioning apparatus which can ensure the dehumidification performance at the time of heating operation favorably, and the vehicle air conditioning apparatus 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 of a 1st proportional valve. It is explanatory drawing showing the operation state of a 1st proportional valve. It is sectional drawing showing the specific structure of a 1st proportional valve. It is explanatory drawing showing the operation state of a 2nd proportional valve. It is explanatory drawing showing the operation state of a 2nd proportional valve. It is sectional drawing showing the specific structure of the 2nd control valve unit which concerns on 2nd Embodiment. It is sectional drawing showing the specific structure of the 2nd proportional valve which concerns on 3rd 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 second control valve 32 (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 first control valve 31 and a second control valve 32. The first control valve 31 includes a valve portion that opens and closes the second passage 22 and a solenoid that drives the valve portion, and adjusts the opening degree of the second passage 22 by opening and closing the valve portion according to the presence or absence of supply current. . In the present embodiment, as the first control valve 31, an on-off valve (on / off valve) that opens and closes depending on whether or not energization is used. On the other hand, the second control valve 32 includes a valve portion that opens and closes the bypass passage 29 and a solenoid that drives the valve portion, and opens the bypass passage 29 by adjusting the opening of the valve portion according to the supply current value. Adjust the degree. In the present embodiment, as the second control valve 32, an on-off valve (on / off valve) that opens and closes depending on whether or not energization is used.

  In the modification, the second control valve 32 has a front-rear differential pressure (a differential pressure between the upstream pressure and the downstream pressure of the second control valve 32) exceeding a set value (a valve opening differential pressure set in advance). And a differential pressure valve that autonomously opens. Alternatively, it may be a constant differential pressure valve in which the valve part operates autonomously so that the differential pressure before and after becomes a constant value according to the supply current value. Alternatively, it may be a proportional valve that operates so that the opening degree of the valve portion becomes a constant opening degree corresponding to the driving force. In that case, the opening degree of the valve portion may be a constant opening degree corresponding to the supply current value. The second control valve 32 may also be a flow rate control valve that controls the flow of the refrigerant so as to have a constant flow rate according to the supply current. Or the constant pressure valve which operate | moves so that the upstream pressure may become a fixed value according to a supply electric current value may be sufficient. Or you may comprise as a control valve ("evaporation superheat degree control valve") which controls the flow of a refrigerant | coolant so that the superheat degree (superheat) of the outdoor heat exchanger 5 may become a fixed superheat degree according to supply current. . Each of the first control valve 31 and the second control valve 32 may be an electromagnetic valve having a solenoid as an actuator, or may be an electric valve having an electric motor such as a stepping motor as an actuator.

  The second control valve unit 6 includes a first proportional valve 41 (functioning as a “regulating valve”) and a second proportional valve 42 (functioning as a “composite valve”). The first proportional valve 41 includes a valve part that opens and closes the first branch passage 26 and an actuator that drives the valve part, and the opening degree of the first refrigerant circulation passage is adjusted by controlling the opening degree of the valve part. To do. The second proportional valve 42 includes a first valve that opens and closes the second branch passage 27, a second valve that opens and closes the connection passage 28, and a common actuator that drives the first valve and the second valve. However, when one of the first valve and the second valve is opened, the other is closed, and the first valve and the second valve are not linearly controlled simultaneously. In other words, since linear control is not performed at the same time, drive control can be performed with one actuator. In the present embodiment, the actuator of the second proportional valve 42 is composed of a solenoid, but in a modified example, it may be composed of a stepping motor.

  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 controls the opening / closing of each control valve (first control valve 31, second control valve 32) of the first control valve unit 4, and each control valve (first proportional valve 41, second control valve) of the second control valve unit 6. In addition to opening / closing control of the 2 proportional valve 42), drive control of the compressor 2, the indoor fan 12, the outdoor fan 16, and the air mix door 14 is also executed.

  The control unit 100 includes a drive signal output unit that outputs a pulse signal set in the drive circuit of each control valve of the second control valve unit 6. 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 each proportional valve 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 like, and opens each proportional valve. Current is supplied to the solenoid so that the degree becomes the set opening degree. In addition, when the actuator of each proportional valve is comprised by a stepping motor as a modification, a control pulse signal is output to a stepping motor so that the opening degree of each proportional valve 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 first valve of the first proportional valve 41 and the second proportional valve 42 has a high upstream pressure P1, and the downstream side of the second valve of the first proportional valve 41 and the second proportional valve 42 has a low pressure. It becomes the downstream pressure P3. The intermediate pressure P2 is the downstream side of the first valve of the second proportional valve 42 and the upstream side of the second valve.

  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, during the cooling operation, the first control valve 31 is opened in the first control valve unit 4, and the second control valve 32 is closed. On the other hand, the first proportional valve 41 is opened in the second control valve unit 6. Further, the first valve of the second proportional valve 42 is closed and the second valve is opened. At this time, the outdoor heat exchanger 5 functions as an outdoor condenser. That is, the refrigerant discharged from the compressor 2 circulates through the first refrigerant circulation passage so as to pass through the indoor condenser 3, the first proportional valve 41, the evaporator 7, and the accumulator 8, and returns to the compressor 2. On the other hand, the first control valve 31, the outdoor heat exchanger 5, the second valve of the second proportional valve 42, the evaporator 7, and the accumulator 8 are circulated through the third refrigerant circulation passage and returned 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 first proportional valve 41, and is introduced into the evaporator 7 as a cold / low pressure gas-liquid two-phase refrigerant. The refrigerant that has passed through the outdoor heat exchanger 5 is adiabatically expanded by the second valve of the second proportional valve 42 and is introduced into the evaporator 7 as a cold / low pressure gas-liquid two-phase refrigerant. And it evaporates in the process which passes the evaporator 7, and cools the air in a vehicle interior. 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, during the heating operation, the first control valve 31 is closed and the second control valve 32 is opened in the first control valve unit 4. On the other hand, the first proportional valve 41 is opened in the second control valve unit 6. Further, the first valve of the second proportional valve 42 is opened, and the second valve is closed. At this time, the outdoor heat exchanger 5 functions as an outdoor evaporator. That is, the refrigerant discharged from the compressor 2 circulates through the first refrigerant circulation passage so as to pass through the indoor condenser 3, the first proportional valve 41, the evaporator 7, and the accumulator 8, and returns to the compressor 2. On the other hand, the refrigerant is circulated through the second refrigerant circulation passage through the indoor condenser 3, the first valve of the second proportional valve 42, the outdoor heat exchanger 5, the second control valve 32, and the accumulator 8 to the compressor 2. Return.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed through the indoor condenser 3. The cold / low pressure gas / liquid two-phase refrigerant adiabatically expanded by the first proportional valve 41 evaporates in the evaporator 7. On the other hand, the cold / low pressure gas-liquid two-phase refrigerant adiabatically expanded by the first valve of the second proportional valve 42 evaporates in the outdoor heat exchanger 5. At this time, the ratio of evaporation in both the outdoor heat exchanger 5 and the evaporator 7 is controlled by setting the respective opening degrees of the first proportional valve 41 and the second proportional valve 42. 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 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. 2B, 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 (superheat). For this reason, by adjusting the opening degree of each of the first valves of the first proportional valve 41 and the second proportional valve 42 so that the degree of superheat at the outlet of the outdoor heat exchanger 5 becomes appropriate, the evaporator 7 The wetness can be secured and the dehumidifying performance can be maintained.

  For example, the control unit 100 calculates the degree of superheat from the temperature at the outlet of the outdoor heat exchanger 5 and opens the respective first valves of the first proportional valve 41 and the second proportional valve 42 so as to obtain an appropriate value. Adjust. 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 there is an operation mode in which the degree of superheat is to be generated in the evaporator 7, conversely, the outlet of the evaporator 7 The degree of superheat is calculated from the temperature of the water, and the respective opening degrees of the first proportional valve 41 and the second proportional valve 42 are adjusted so that this becomes an appropriate value, whereby the wetness in the outdoor heat exchanger 5 is determined. The degree can also be adjusted.

  In addition, as shown in FIG. 2C, during the specific heating operation, the second control valve 32 is opened in the first control valve unit 4 and the first control valve 31 is closed. On the other hand, the first proportional valve 41 is closed in the second control valve unit 6. Further, the first valve of the second proportional valve 42 is opened, and the second valve is closed. 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 is circulated through the second refrigerant so as to pass through the indoor condenser 3, the first valve of the second proportional valve 42, the outdoor heat exchanger 5, the second control valve 32, and the accumulator 8. Circulate through the passage and return 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 and is adiabatically expanded by the first valve of the second proportional valve 42 to be a cold / low-pressure gas-liquid two-phase refrigerant. And passes through the outdoor heat exchanger 5 and is evaporated. The refrigerant that has passed through the outdoor heat exchanger 5 returns to the compressor 2 via 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.

  As shown in FIG. 2D, the first control valve 31 and the second control valve 32 are 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 41 is opened. Further, both the first valve and the second valve of the second proportional valve 42 are 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 circulates in the first refrigerant circulation passage so as to pass through the indoor condenser 3, the first proportional valve 41, the evaporator 7, and the accumulator 8, 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 and is adiabatically expanded by the first proportional valve 41 to become a cold / low-pressure gas-liquid two-phase refrigerant. 7 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 second control valve unit 6 will be described. As described above, the second control valve unit 6 includes the first proportional valve 41 and the second proportional valve 42. First, the specific configuration and operation of the first proportional valve 41 will be described. FIG. 3 is a cross-sectional view illustrating a specific configuration of the first proportional valve 41. In the following description, for the sake of convenience, the positional relationship between the structures may be expressed based on the illustrated state.

  The first proportional valve 41 is configured by assembling a valve body 101 and a solenoid 102. The first proportional valve 41 is a pilot-operated solenoid valve that can take an arbitrary opening degree in accordance with the supply current value to the solenoid 102. The valve body 101 is configured by housing a main valve 105 and a pilot valve 106 coaxially with a central axis in a bottomed cylindrical body 103. An inlet port 110 is provided on one side of the body 103 and an outlet port 112 is provided on the other side. The inlet port 110 communicates with the upstream passage (first branch passage 26) in the refrigeration cycle, and the outlet port 112 communicates with the downstream passage (fourth passage 24) of the refrigeration cycle.

  The internal space of the body 103 communicates with the inlet port 110 through the high pressure passage 114 and communicates with the outlet port 112 through the low pressure passage 115. A main valve hole 120 is provided so as to connect the high-pressure passage 114 and the low-pressure passage 115 along the central axis. That is, the internal space of the body 103 is partitioned into a pressure chamber 116 on the high pressure passage 114 side and a pressure chamber 118 on the low pressure passage 115 side by a partition wall in which the main valve hole 120 is formed. An annular seal member 121 is fitted to surround the upstream opening of the main valve hole 120. The seal member 121 is made of an elastic body (rubber in this embodiment), and is fixed to the body 103 by a mounting ring 122. A bottomed stepped cylindrical main valve body 124 is disposed in the internal space of the upper half of the body 103.

  The main valve body 124 contacts and separates from the main valve hole 120 from the high pressure passage 114 side to open and close the main valve 105. The main valve 105 is a so-called spool valve, and opens and closes the main valve 105 so that the lower end portion of the main valve body 124 is inserted into and removed from the main valve hole 120. That is, the main valve body 124 can be stroked in a predetermined range in the axial direction when the valve is closed, and the bottom dead center is defined by being locked by the seal member 121. In the valve-closed state as shown in the figure, the main valve body 124 is in close contact with the upper end surface of the seal member 121, so that leakage of the refrigerant through the gap with the main valve hole 120 is reliably prevented. A flange portion 126 extending outward in the radial direction is provided at the upper end opening of the main valve body 124, and is slidably supported on the inner peripheral surface of the body 103. A sealing O-ring 128 is fitted on the outer peripheral surface of the flange portion 126. The main valve body 124 partitions the pressure chamber 116 into a high pressure chamber 130 and a back pressure chamber 132.

  A stepped disk-shaped partition member 134 is press-fitted so as to seal the upper end opening of the body 103. The partition member 134 is provided so that its outer diameter is gradually reduced downward and its lower end seals the back pressure chamber 132 from above. An O-ring 136 for sealing is interposed between the outer peripheral surface of the lower end portion of the partition member 134 and the inner peripheral surface of the body 103. That is, the main valve body 124 forms a back pressure chamber 132 between the partition member 134. The lower end surface of the partition member 134 functions as a locking portion that locks the main valve body 124 and defines its top dead center.

  The partition member 134 is provided with a through hole 138 along the axis, the pilot valve hole 140 is formed by the lower end portion of the through hole 138, and the guide hole 142 is formed by the upper half portion. In addition, a communication path 144 is extended radially outward from the through hole 138 to communicate the inside and outside of the partition member 134. On the other hand, in the vicinity of the peripheral portion of the body 103, a communication passage 146 is provided that allows the upper end opening and the low-pressure passage 115 to communicate vertically. A pilot passage 148 is formed by the communication passage 144 and the communication passage 146.

  An orifice 150 (functioning as a “leak passage”) that connects the high pressure chamber 130 and the back pressure chamber 132 is provided on the side of the main valve body 124. The pressure in the high-pressure chamber 130 (upstream pressure P <b> 1) passes through the orifice 150 and becomes an intermediate pressure Pp in the back pressure chamber 132. Further, the upstream pressure P1 is reduced through the main valve 105 to become a pressure (downstream pressure P3). The intermediate pressure Pp varies depending on the open / close state of the pilot valve 106. A passage connecting the high pressure chamber 130 and the pressure chamber 118 via the main valve 105 constitutes a “main passage”, and the high pressure chamber 130 and the pressure chamber 118 are connected via the back pressure chamber 132, the pilot valve 106 and the pilot passage 148. The connecting passage forms a “sub-passage”.

  The pilot valve 106 has a pilot valve body 152 that is inserted into and removed from the pilot valve hole 140. The pilot valve body 152 is integrally formed at the lower end portion of the long cylindrical operating rod 154. The operating rod 154 extends along the central axis of the solenoid 102, and a lower end portion thereof is slidably supported by the guide hole 142, and an upper end portion is connected to a plunger 172 (described later). The pilot valve body 152 is connected to the lower end portion of the operating rod 154 via a reduced diameter portion connected to the tapered surface. A through hole 156 is formed along the axis of the operating rod 154. The through hole 156 allows the inside of the solenoid 102 and the back pressure chamber 132 to communicate with each other. One end of the through hole 156 opens to the side of the pilot valve body 152 as the refrigerant inlet 157, and the other end opens to the internal space of the solenoid 102. In addition, a communication hole 158 that allows communication between the inside and the outside is formed in an intermediate portion of the operating rod 154.

  A seal member 155 made of an annular elastic body (rubber in the present embodiment) is fitted to the central portion in the axial direction of the pilot valve body 152. In the fully closed state of the pilot valve 106 as shown in the figure, the seal member 155 is seated on the opening edge of the pilot valve hole 140 to reliably prevent the refrigerant from leaking through the pilot valve 106 and to prevent the through hole 156 from being formed. The refrigerant circulation is also blocked.

  Between the main valve body 124 and the pilot valve body 152 in the back pressure chamber 132, a balance mechanism having a double spring structure is provided. That is, a bottomed cylindrical spring receiving member 160 is joined to the lower half portion of the pilot valve body 152 at its upper bottom portion. A flange portion 161 that protrudes slightly outward in the radial direction is provided at the lower end portion of the spring receiving member 160. In addition, a cylindrical spring receiving member 162 is disposed so as to be externally inserted into the spring receiving member 160 and constitutes a double structure of the spring receiving member. A flange portion 163 that protrudes slightly inward in the radial direction is provided at the upper end portion of the spring receiving member 162, and a flange portion 164 that protrudes slightly outward in the radial direction is provided at the lower end portion.

  A spring 165 (elastic member) is interposed between the flange portion 161 and the flange portion 163, and a spring 166 (elastic member) is interposed between the flange portion 164 and the partition member 134. In other words, the spring 165 is disposed so as to be externally inserted into the spring receiving member 160 and inserted into the spring receiving member 162. The spring 166 is externally inserted into the spring receiving member 162 and is disposed so as to be inserted into the upper half portion of the main valve body 124 and the lower end portion of the partition member 134. In this way, a double structure of the spring is realized. With such a configuration, the main valve body 124 is urged in the valve closing direction by the spring 166, and the pilot valve body 152 is urged in the valve opening direction by the spring 165. The spring receiving member 162 is always pressed against the main valve body 124 by the load of the spring 166 and operates integrally with the main valve body 124. Thus, since the spring receiving member and the spring have different diameters on the same axis and are accommodated in the back pressure chamber 132 so as to overlap in the axial direction, the relatively long spring 166 is accommodated in the back pressure chamber 132 in a compact manner. it can. In the modification, the spring receiving member 162 may be fixed by being press-fitted into the main valve body 124.

  Here, the pilot valve hole 140 has a channel cross-sectional area sufficiently larger than the orifice 150. In this embodiment, the pilot valve hole 140 has a flow path cross-sectional area that is at least 5 times, preferably 10 times or more larger than the orifice 150. For this reason, when the pilot valve 106 is opened, the amount of refrigerant flowing out from the back pressure chamber 132 becomes considerably larger than the amount of refrigerant flowing into the back pressure chamber 132. That is, as shown in the figure, when the pilot valve 106 is closed, the intermediate pressure Pp is maintained at a high pressure substantially equal to the upstream pressure P1, but when the pilot valve 106 is opened, the intermediate pressure Pp quickly decreases. As a result, the pressure approaches the downstream pressure P3.

  On the other hand, the solenoid 102 is attached so as to seal the upper end portion of the body 103. A seal ring 168 is interposed between the solenoid 102 and the body 103. The solenoid 102 includes a cylindrical sleeve 170, a cylindrical core 171 (which functions as a “second iron core” and a “fixed iron core”) fixed to the lower portion of the sleeve 170, and an axial direction of the core 171 in the sleeve 170. And a plunger 172 (functioning as a “first iron core” and a “movable iron core”) disposed opposite to each other. A bobbin 173 is provided on the outer periphery of the sleeve 170, and an electromagnetic coil 174 is wound around the bobbin 173. A case 176 is provided so as to cover the electromagnetic coil 174 from the outside. The sleeve 170 penetrates the case 176 in the axial direction. A current-carrying harness 178 is drawn out from the electromagnetic coil 174.

  The core 171 has a cylindrical shape, and is fixed so that a lower portion thereof is press-fitted into a through hole of the case 176. The aforementioned operating rod 154 passes through the core 171 along its axis, and is fixed so that its upper end is press-fitted into the center of the plunger 172. That is, the pilot valve body 152 operates integrally with the plunger 172.

  The plunger 172 has a cylindrical shape, and a spring receiving portion 180 that protrudes inward in the radial direction is provided at the center in the axial direction. The upper end portion of the operating rod 154 is press-fitted into the inner peripheral surface of the spring receiving portion 180. A spring 182 (corresponding to an “urging member”) is interposed between the spring receiving portion 180 of the plunger 172 and the upper end surface of the core 171. A spring 184 (corresponding to an “urging member”) is interposed between the spring receiving portion 180 of the plunger 172 and the bottom portion of the sleeve 170. The spring 182 biases the pilot valve body 152 in the valve closing direction via the plunger 172. The spring 184 is a spring for adjusting the load of the spring 182.

  When the first proportional valve 41 is made to function, a minimum current (also referred to as “valve opening current”, for example, non-energization that realizes a fully closed state) that realizes a desired minimum opening and a desired maximum opening are realized. The supply current of the solenoid 102 is controlled within a range determined by the maximum current (for example, a predetermined current value that realizes the fully opened state). The dynamic characteristic of the spring 165 is set so that the range of the elastic deformation amount of the spring 165 is larger than the stroke of the plunger 172 in this control range. For example, by making the spring constant of the spring 165 relatively small, the elastic deformation range corresponding to the control current range can be increased.

The first proportional valve 41 configured as described above functions as a pilot-actuated control valve that can control the flow from the upstream side to the downstream side at an arbitrary opening according to the value of the current supplied to the solenoid 102. . Hereinafter, the operation will be described in detail.
FIG. 4 is an explanatory diagram showing the operating state of the first proportional valve. FIG. 4 shows a control state in which the solenoid 102 is turned on. Note that FIG. 3 already described represents a state in which the solenoid 102 is turned off.

  In the non-energized state in which the solenoid 102 is turned off, the first proportional valve 41 holds the valve closed state without performing the valve opening degree adjustment control (see FIG. 2C). That is, as shown in FIG. 3, since the solenoid force does not act, the pilot valve body 152 is urged in the valve closing direction by the spring 182 and the pilot valve 106 is closed. At this time, since the refrigerant is introduced into the back pressure chamber 132 from the upstream side via the orifice 150, the intermediate pressure Pp approaches the upstream pressure P1. As a result, the differential pressure (Pp−P3) in the valve closing direction acts largely on the main valve body 124, and the main valve 105 is also closed. At this time, as shown in the figure, the seal member 155 is seated on the partition member 134 to seal the pilot valve 106 and to block the refrigerant flow through the through hole 156. For this reason, the differential pressure (Pp−Pso) in the valve closing direction also acts on the pilot valve body 152, and the stable valve closing state of the pilot valve 106 can be maintained (Pso: sleeve 170 of the solenoid 102). Inside pressure). As a result, the supply of the refrigerant to the evaporator 7 via the first branch passage 26 is interrupted.

  On the other hand, in the energized state where the solenoid 102 is turned on, the first proportional valve 41 operates so that the opening degree becomes a set opening degree corresponding to the supply current value (FIGS. 2A, 2B, ( D)). That is, as shown in FIG. 4, since a suction force acts between the core 171 and the plunger 172 by the solenoid force, the pilot valve body 152 is urged in the valve opening direction, and the pilot valve 106 is opened. . As a result, the intermediate pressure Pp decreases and approaches the downstream pressure P3, so that a differential pressure (P1-Pp) in the valve opening direction acts on the main valve body 124 greatly, and the main valve 105 is also in the valve open state. Become. The main valve body 124 is held at a position where the force in the valve opening direction due to the differential pressure (P1-Pp) and the force in the valve closing direction due to the spring 166 are balanced, and the opening degree of the main valve 105 is adjusted to the set opening degree. Is done.

  At this time, the pilot valve body 152 is controlled so as to be separated from the pilot valve hole 140 and keep the pilot valve 106 at a minute opening. At this time, the seal member 155 is separated from the partition member 134 to allow the refrigerant to flow through the through hole 156. Further, since the effective diameters of the pilot valve hole 140 and the guide hole 142 are equal, the force due to the intermediate pressure Pp acting on the pilot valve body 152 is canceled. The pilot valve body 152 is held at a minute opening position where the suction force in the valve opening direction by the solenoid 102, the force in the valve closing direction by the spring 182 and the force in the valve opening direction by the spring 165 are balanced.

  When the main valve body 124 is displaced in the valve closing direction (downward in the figure) by the opening degree Δd in the state where the main valve 105 is adjusted to the set opening degree in this way, the pilot valve 106 is driven by the elastic force of the spring 165. Operates in the valve opening direction (downward). Then, since the intermediate pressure Pp in the back pressure chamber 132 approaches the downstream pressure P3, the main valve body 124 is returned in the valve opening direction (upward) by the action of the differential pressure. On the contrary, when the main valve body 124 is displaced in the valve opening direction (upward) by the opening degree Δd, the deformation amount of the spring 165 and thus the spring force is also reduced. Therefore, the decrease in the spring force acts as a restoring force, and the pilot valve 106 operates in the valve closing direction (upward). As a result, the intermediate pressure Pp increases, and the main valve body 124 is returned in the valve closing direction (downward). In this way, the opening degree of the main valve 105 is maintained at a magnitude corresponding to the control current. In this control state, supply of the refrigerant to the evaporator 7 through the first branch passage 26 is allowed. That is, a refrigerant having a flow rate corresponding to the opening degree of the first proportional valve 41 is supplied to the evaporator 7.

  The set opening degree of the first proportional valve 41 can be changed by changing the supply current value to the solenoid 102. Since the first proportional valve 41 of the present embodiment is configured as a normally closed electromagnetic proportional valve, the valve opening increases proportionally when the control current is increased. In the present embodiment, the pilot valve hole 140 having a sufficiently larger channel cross-sectional area than the orifice 150 contributes to suppressing the displacement amount of the plunger 172 to be extremely small. When pilot valve hole 140 has a sufficiently large channel cross-sectional area, the sensitivity of intermediate pressure Pp in back pressure chamber 132 can be increased with respect to minute movement of pilot valve 106. That is, when the pilot valve 106 is slightly opened in the proportional control state, the intermediate pressure Pp is rapidly reduced to the downstream pressure P3.

  That is, by making the flow path cross-sectional area of the pilot valve hole 140 considerably larger than that of the orifice 150, the intermediate pressure Pp is changed between the upstream pressure P1 and the downstream pressure P3 by a small change in the opening degree of the pilot valve 106. It is possible to change greatly. In other words, even if the supply current value is changed to change the intermediate pressure Pp greatly in order to change the set opening of the main valve 105, the displacement of the pilot valve body 152 can be kept small. At this time, since the differential pressure applied to the main valve body 124 changes due to the change in the intermediate pressure Pp, the length of the spring 165, that is, the stroke of the main valve body 124 changes greatly so as to generate a spring load that balances the differential pressure. Will come to do. That is, the deformation range of the spring 165 is larger than the fluctuation range of the gap between the core 171 and the plunger 172, and the stroke of the main valve body 124 is larger than the relative movement stroke of the core 171 and the plunger 172.

  Next, a specific configuration and operation of the second proportional valve 42 will be described. FIG. 5 is a cross-sectional view illustrating a specific configuration of the second proportional valve 42. Since the second proportional valve 42 includes the same configuration as the first proportional valve 41 already described, the same configuration is denoted by the same reference numeral, and the description thereof is omitted as appropriate.

  The second proportional valve 42 is configured by assembling a valve body 201 and a solenoid 102. The valve main body 201 is coaxial with the center axis of a main valve 105 (functioning as a “first valve”), a pilot valve 106, and an auxiliary valve 205 (functioning as a “second valve”) on a cylindrical body 203 with a bottom. It is housed and configured. The valve main body 201 is further provided with a differential pressure valve 207 (functioning as a “first differential pressure valve”) for switching the auxiliary passage. An entrance / exit port 212 is provided on the same side of the body 203 as the entrance port 110. The inlet port 110 communicates with the second branch passage 27, the inlet / outlet port 212 communicates with the fifth passage 25, and the outlet port 112 communicates with the connection passage 28 (see FIG. 1).

  An intermediate passage 210 is provided between the main valve 105 and the sub valve 205 in the body 203. The intermediate passage 210 is provided between the high-pressure passage 114 and the low-pressure passage 115 so as to separate both passages, and communicates with the inlet / outlet port 212. A main valve hole 120 is provided so as to connect the high pressure passage 114 and the intermediate passage 210 along the central axis, and a sub valve hole 214 is provided so as to connect the intermediate passage 210 and the low pressure passage 115 along the central axis. Is provided. That is, the internal space of the body 103 is partitioned into a pressure chamber 116 on the high pressure passage 114 side and a pressure chamber 117 on the intermediate passage 210 side by a partition wall in which the main valve hole 120 is formed. Further, the pressure chamber 117 on the intermediate passage 210 side and the pressure chamber 118 on the low pressure passage 115 side are partitioned by a partition wall in which the sub valve hole 214 is formed.

  Unlike the main valve body 124 of the first embodiment, the main valve body 224 is provided with a guide hole 226 that communicates the inside and the outside in the axial direction at the lower end portion thereof. A sealing member 228 is press-fitted so as to seal the upper surface of the main valve body 224, and a pressure chamber 229 is formed in a space surrounded by the sealing member 228 and the main valve body 224. A refrigerant having an intermediate pressure P2 in the pressure chamber 117 is introduced into the pressure chamber 229 through the guide hole 226.

  The sub valve 205 has a sub valve body 230 that contacts and separates from the sub valve hole 214 to open and close it. The auxiliary valve body 230 has a spool valve configuration having a tapered surface, and opens and closes the auxiliary valve 205 by being inserted into and extracted from the auxiliary valve hole 214 from the low pressure passage 115 side. That is, the sub-valve body 230 can make a stroke within a predetermined range in the axial direction when the valve is closed. On the other hand, a long operating rod 232 extends from the sub-valve body 230 upward. The actuating rod 232 passes through the guide hole 226 across the intermediate passage 210, and its distal end is disposed in the pressure chamber 229. A cylindrical stopper 234 is press-fitted into the distal end portion of the operating rod 232. As the operating rod 232 slides in the axial direction along the guide hole 226, the main valve body 224 and the sub-valve body 230 can be independently displaced. However, when the stopper 234 is locked to the main valve body 224, the independent displacement is restricted, and the main valve body 224 and the sub-valve body 230 come to operate integrally.

  A seal member 236 made of an annular elastic body (rubber in the present embodiment) is fitted to the central portion of the auxiliary valve body 230 in the axial direction. In the fully closed state of the auxiliary valve 205 as shown in the figure, the seal member 236 is seated on the opening edge of the auxiliary valve hole 214 to reliably prevent the refrigerant from leaking through the auxiliary valve 205. The lower half of the auxiliary valve body 230 has a cylindrical diameter and slides along the inner wall of the body 203. A communication hole 238 that communicates inside and outside is formed in the cylindrical portion. A spring receiving member 240 is press-fitted into the center of the lower end portion of the body 203, and a spring 242 for biasing the sub valve body 230 in the valve closing direction is interposed between the sub valve body 230 and the spring receiving member 240. Yes.

  A space in which the spring 242 is disposed is a small back pressure chamber 244, and the downstream pressure P3 is introduced through the communication hole 238. That is, it is ensured that the downstream pressure P3 acts on the lower surface of the auxiliary valve body 230. The sub-valve body 230 opens when the front-rear differential pressure (P2-P3) becomes larger than the set differential pressure ΔPset1 (open valve differential pressure). The set differential pressure ΔPset1 is set by adjusting the load of the spring 242 determined by the amount of press-fitting of the spring receiving member 240 into the body 203. That is, the auxiliary valve 205 functions as a proportional valve as described later and also functions as a differential pressure valve (second differential pressure valve).

  The differential pressure valve 207 is provided at a connection portion between the intermediate passage 210, the low pressure passage 115, and the pilot passage 148, and switches the sub passage in the second proportional valve. The differential pressure valve 207 is a valve including a first valve portion 251 and a second valve portion 252 and is configured so that the common valve body 253 is inserted into a stepped cylindrical body 250. A port 254 communicating with the pilot passage 148 is provided at the center of the side portion of the body 250. The O-ring 256 is provided on one side of the port 254 on the outer peripheral surface of the body 250, and the O-ring 258 is provided on the other side, so that the refrigerant leaks through the gap between the outer peripheral surface of the body 250 and the body 203. Is prevented.

  A valve hole 260 is provided on one side of the port 254 in the body 250, and a valve seat 262 is provided at the open end thereof. Further, a valve hole 264 is provided on the other side of the port 254 in the body 250, and a valve seat 266 is provided at the opening end thereof. The valve hole 260 and the valve hole 264 are coaxially provided on the central axis. The common valve body 253 passes through the valve hole 260 and the valve hole 264, a differential pressure valve body 270 is provided on one end side thereof, and a differential pressure valve body 272 is provided on the other end side. In this embodiment, since the effective diameters of the valve hole 260 and the valve hole 264 are configured to be equal, the influence of the pressure acting on the shared valve body 253 due to the refrigerant introduced from the pilot passage 148 is cancelled.

  A valve member 274 made of an annular elastic body (rubber in this embodiment) is fitted to the differential pressure valve body 270, and the valve member 274 is attached to and detached from the valve seat 262 to open and close the first valve portion 251. The differential pressure valve body 272 is fitted with a valve member 276 made of an annular elastic body (rubber in the present embodiment), and the valve member 276 is attached to and detached from the valve seat 266 to open and close the second valve portion 252. A spring 278 that biases the common valve body 253 in the valve opening direction of the first valve portion 251 (the valve closing direction of the second valve portion 252) is interposed between the body 250 and the differential pressure valve body 270. .

  The common valve body 253 maintains the state in which the first valve portion 251 is opened and the second valve portion 252 is closed as shown in the drawing if the front-rear differential pressure (P2-P3) is equal to or less than the set pressure ΔPset2. . When the front-rear differential pressure (P2-P3) becomes larger than the set differential pressure ΔPset2, the common valve body 253 moves to the left in the figure against the urging force of the spring 278 to close the first valve portion 251 and to The valve part 252 is opened. The set differential pressure ΔPset2 is set by adjusting the load of the spring 278. In the present embodiment, the set differential pressure ΔPset2 is set to be approximately equal to the set differential pressure ΔPset1 of the sub valve 205. For this reason, these set differential pressures are also expressed as set differential pressures ΔPset. In order to maintain a stable opening / closing operation of the secondary valve 205, the set differential pressure ΔPset2 of the differential pressure valve 207 should be equal to or smaller than the set differential pressure ΔPset1 of the secondary valve 205 (ΔPset2 ≦ ΔPset1).

  A communication groove 280 is provided on the side surface of the shared valve body 253, and one of the intermediate passage 210 and the low pressure passage 115 and the pilot passage 148 communicate with each other according to the open / close state of the first valve portion 251 and the second valve portion 252. Let That is, as shown in the figure, the pilot passage 148 communicates with the intermediate passage 210 when the first valve portion 251 is open, and communicates with the low pressure passage 115 when the second valve portion 252 is open.

  In such a configuration, the passage connecting the high pressure passage 114 and the intermediate passage 210 via the main valve 105 constitutes a “first main passage”, and the high pressure passage 114 and the intermediate passage 210 are connected to the back pressure chamber 132, the pilot valve. 106, the passage connecting the pilot passage 148 and the first valve portion 251 constitutes a “first sub-passage”. The passage connecting the intermediate passage 210 and the low pressure passage 115 via the sub valve 205 constitutes a “second main passage”, and the high pressure passage 114 and the low pressure passage 115 are connected to the back pressure chamber 132, the pilot valve 106, the pilot passage. A passage connecting 148 and the second valve portion 252 constitutes a “second auxiliary passage”.

The second proportional valve 42 configured as described above functions as a pilot-actuated compound valve that can control the flow from the upstream side to the downstream side at an arbitrary opening degree according to the supply current value to the solenoid 102. . Hereinafter, the operation will be described in detail.
6 and 7 are explanatory diagrams showing the operating state of the second proportional valve. FIG. 6 shows a state (P2−P3> ΔPset) where the differential pressure before and after the differential pressure valve 207 is larger than the set differential pressure in the control state where the solenoid 102 is turned on. FIG. 7 shows a state (P2−P3 <ΔPset) in which the front-rear differential pressure is smaller than the set differential pressure in the control state. 6 corresponds to FIG. 2A, and the control state in FIG. 7 corresponds to FIGS. 2B and 2C. FIG. 5 which has already been described represents a state in which the solenoid 102 is turned off, and corresponds to FIG.

  That is, as shown in FIG. 5, in the non-energized state where the solenoid 102 is turned off, the second proportional valve 42 maintains the closed state without performing the valve opening adjustment control. That is, since the solenoid force does not act, the pilot valve 106 is closed. At this time, since the refrigerant is introduced into the back pressure chamber 132 from the upstream side via the orifice 150, the intermediate pressure Pp approaches the upstream pressure P1. As a result, the differential pressure (Pp−P2) in the valve closing direction acts on the main valve body 124 greatly, and the main valve 105 is also closed. Further, since the intermediate pressure P2 does not increase due to the closing of the main valve 105, the differential pressure (P2-P3) is smaller than the set differential pressure ΔPset, and the sub valve 205 is also closed. Further, the differential pressure valve 207 maintains the open state of the first valve portion 251. As a result, the refrigerant circulation through the second refrigerant circulation passage and the refrigerant circulation through the third refrigerant circulation passage are both blocked (see FIG. 2D).

  On the other hand, in the energized state where the solenoid 102 is turned on, a suction force acts between the core 171 and the plunger 172 by the solenoid force, so that the pilot valve body 152 is urged in the valve opening direction and the pilot valve 106 is opened. It becomes a valve state. As a result, the intermediate pressure Pp is lowered, so that a differential pressure (P1-Pp) in the valve opening direction acts on the main valve body 224, and the main valve 105 is displaced in the valve opening direction. Since the main valve body 224 and the sub-valve body 230 are spool valves, each has a valve closing stroke within a predetermined range, and the valve cannot be opened unless the predetermined stroke is displaced. The main valve 105 or the sub valve 205 operates so that the opening degree becomes a set opening degree corresponding to the supply current value (see FIGS. 2A to 2C).

  That is, as shown in FIG. 6, in the control state where the differential pressure (P2−P3) is larger than the set differential pressure ΔPset, the auxiliary valve body 230 operates in the valve opening direction against the urging force of the spring 242. The sub valve 205 is opened. Further, in the differential pressure valve 207, the second valve portion 252 is opened and the first valve portion 251 is closed. At this time, when the stopper 234 is locked to the main valve body 224, the sub-valve body 230 and the main valve body 224 are integrally operated so as to pull each other in the axial direction, and the main valve 105 is maintained in the closed state. To do. That is, the auxiliary valve body 230 operates integrally with the main valve body 224, and the valve closing direction force due to the differential pressure (P1-Pp), the valve opening direction force due to the spring 166, and the differential pressure (P2-P3). Is held at a position where the force in the valve opening direction due to is balanced with the force in the valve closing direction due to the spring 242, thereby maintaining the sub-valve 205 at the set opening. This set opening degree changes proportionally according to the supply current value to the solenoid 102. As a result, the circulation of the refrigerant through the second refrigerant circulation passage is substantially interrupted (there may be some leakage through the gap of the spool valve), but the circulation of the refrigerant through the third refrigerant circulation passage is permitted (see FIG. 2 (A)).

  On the other hand, as shown in FIG. 7, in the control state where the differential pressure (P2−P3) is smaller than the set differential pressure ΔPset, the auxiliary valve 205 maintains the closed state by the urging force of the spring 242. In the differential pressure valve 207, the valve opening state of the first valve portion 251 is maintained. At this time, since the stopper 234 does not restrict the operation of the main valve body 224, the main valve body 224 operates independently of the sub valve body 230. That is, the main valve 105 basically operates in the same manner as the main valve 105 of the first proportional valve 41 in the first embodiment.

  When the supply current value to the solenoid 102 is the maximum, the main valve body 224 is displaced to the top dead center, and the main valve 105 is fully opened. On the other hand, when the supply current value to the solenoid 102 is set to a predetermined current value between the maximum current value and the minimum current value, the main valve body 224 is held at a position corresponding to the predetermined current value. That is, the main valve 105 operates proportionally so as to have a set opening degree corresponding to the current value supplied to the solenoid 102. As a result, the refrigerant circulation through the third refrigerant circulation passage is blocked, but the refrigerant circulation through the second refrigerant circulation passage is permitted (see FIGS. 2B and 2C).

[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 the first embodiment except that the first proportional valve and the second proportional valve 42 of the second control valve unit are integrated. 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. 8 is a cross-sectional view illustrating a specific configuration of the second control valve unit according to the second embodiment.

  The second control valve unit 206 corresponds to an integrated unit of the first proportional valve 41 and the second proportional valve 42 shown in FIG. The second control valve unit 206 is configured by assembling the shared body 303 so that the first proportional valve 41 and the second proportional valve 42 are adjacent to each other. The body 303 has an inlet port 110 connected to the third passage 23, an inlet / outlet port 212 connected to the fifth passage 25, and an outlet port 112 connected to the fourth passage 24. The body 303 is partitioned by a partition wall 310 into a region functioning as the first proportional valve 41 and a region functioning as the second proportional valve 42.

  The first proportional valve 41 has substantially the same configuration as that shown in FIG. Further, the second proportional valve 42 has substantially the same configuration as that shown in FIG. Note that the high-pressure chambers 130 of the proportional valves are connected to each other via a portion of the high-pressure passage 114 (not shown in the drawing). The control unit 100 opens and closes each valve by energizing and controlling each of the first proportional valve 41 and the second proportional valve 42, thereby realizing the same control as that shown in FIG. As shown, the first proportional valve 41 and the second proportional valve 42 have many common components. In other words, the configuration of one of the first proportional valve 41 and the second proportional valve 42 can be changed a little to configure the other, and the design and production of these different types of control valves can be simplified. is there.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The vehicle air conditioning apparatus according to the present embodiment differs from the first embodiment in that a stepping motor is employed as the actuator of the second proportional valve, but there are many common parts. 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 second proportional valve according to the third embodiment.

  The second proportional valve 42 is configured by assembling a valve main body 301 and an actuator 302. The actuator 302 includes a stepping motor that rotates by a predetermined rotation angle in accordance with a pulse of an electric signal, and the amount of rotation is controlled by a control pulse from the control unit 100. The actuator 302 incorporates a gear mechanism that rotates and translates the drive shaft 305 by the rotation of the stepping motor. In addition, since a well-known thing can be employ | adopted as such a stepping motor, the detailed description is abbreviate | omitted.

  The main valve body 324 is fixed to the distal end portion of the drive shaft 305, and the opening degree of the main valve 105 is controlled to an arbitrary opening degree by driving the actuator 302. On the other hand, the operation of the sub valve 205 is the same as in the first embodiment. According to such a configuration, since the main valve 105 is directly controlled by driving the actuator 302, it is not necessary to provide a pilot mechanism. This eliminates the need for a complicated mechanism for driving the main valve 105 as in the first embodiment, and eliminates the need for the differential pressure valve 207. Therefore, the second proportional valve 342 can be manufactured easily and at low cost. Although not described in the present embodiment, the first proportional valve may be similarly driven by the actuator 302.

  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.

  DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner, 2 Compressor, 3 Indoor condenser, 4 First control valve unit, 5 Outdoor heat exchanger, 6 Second control valve unit, 7 Evaporator, 8 Accumulator, 12 Indoor fan, 21 1st passage , 22 2nd passage, 23 3rd passage, 24 4th passage, 25 5th passage, 26 1st branch passage, 27 2nd branch passage, 28 connection passage, 29 bypass passage, 30 return passage, 31 1st control valve 32 Second control valve, 41 First proportional valve, 42 Second proportional valve, 100 Control unit, 101 Valve body, 102 Solenoid, 103 Body, 105 Main valve, 106 Pilot valve, 110 Inlet port, 112 Outlet port, 114 High-pressure passage, 115 Low-pressure passage, 120 Main valve hole, 124 Main valve body, 130 High-pressure chamber, 13 Back pressure chamber, 140 pilot valve hole, 142 guide hole, 148 pilot passage, 150 orifice, 152 pilot valve body, 154 actuating rod, 171 core, 172 plunger, 201 valve body, 203 body, 205 sub valve, 206 second control Valve unit, 207 differential pressure valve, 210 intermediate passage, 212 inlet / outlet port, 214 auxiliary valve hole, 224 main valve element, 226 guide hole, 230 auxiliary valve element, 232 actuating rod, 250 body, 253 common valve element, 260 valve hole, 262 valve seat, 264 valve hole, 266 valve seat, 270, 272 differential pressure valve body, 301 valve body, 302 actuator, 303 body, 324 main valve body, 342 second proportional valve.

Claims (10)

A control valve provided between the first passage, the second passage, and the third passage and capable of controlling the flow of fluid between the passages;
A first valve having a first valve body that opens and closes a first communication passage connecting the first passage and the second passage by contacting and separating from a first valve hole;
A second communication passage that connects the second passage and the third passage has a second valve body that opens and closes by contacting and separating from the second valve hole, and the second valve body is in a closed state; The first valve body can be operated independently, and the second valve body is connected to the first valve body so that the second valve body can operate integrally with the first valve body when the second valve body is open. A second valve;
When the first valve is opened, the first valve body is driven independently of the second valve body to adjust the opening degree of the first valve, while the first valve is closed when the first valve is closed. An actuator that integrally drives the body and the second valve body to adjust the opening of the second valve;
A control valve comprising:   When the first valve body is inserted into and removed from the first valve hole, the first valve is opened and closed, and when the second valve body is inserted into and removed from the second valve hole, the second valve is opened and closed. 2. The control valve according to claim 1, wherein the opening degree of the other of the first valve and the second valve can be adjusted when the first valve and the second valve are closed. The first valve hole and the second valve hole are coaxially arranged opposite to each other,
During the opening control of the first valve, the first valve body and the second valve body are connected so as to be independently operable in the axial direction, and during the opening control of the second valve, the first valve body and the The control valve according to claim 2, further comprising a mechanism that connects the second valve body so as to be integrally operable. A pilot valve driven by the actuator,
The first valve body is provided so as to partition the first passage, the second passage, and a back pressure chamber;
The pilot valve has a pilot valve body that opens and closes by opening / closing a sub-passage that connects the second passage or the third passage and the first passage through the back pressure chamber to and from a pilot valve hole. The pilot valve element operates so that the opening degree of the first valve approaches a set opening degree when the second valve is closed, and the opening degree of the second valve is set when the first valve is closed. The control valve according to claim 1, wherein the control valve operates so as to approach a set opening degree. Comprising a solenoid as the actuator;
The pilot valve element operates to bring the opening degree of the first valve close to a set opening degree corresponding to a supply current value to the solenoid when the second valve is closed, and when the first valve is closed, 5. The control valve according to claim 4, wherein the control valve operates so that the opening degree of the second valve approaches a set opening degree corresponding to a value of a current supplied to the solenoid. A leak passage communicating the first passage with the back pressure chamber in the sub passage;
The solenoid including a first iron core that moves in the axial direction integrally with the pilot valve body, and a second iron core that is arranged to face the first iron core with a gap in the axial direction;
An elastic member interposed between the first valve body and the pilot valve body, and allowing relative displacement between the first valve body and the pilot valve body by expansion and contraction due to elastic deformation thereof;
With
In the energization control state of the solenoid, the first valve and the second valve are controlled to a set opening degree by elastically deforming the elastic member so as to generate a load commensurate with a change in the attraction force of the solenoid. The control valve according to claim 5.   The pilot passage is provided between the pilot passage communicating with the pilot valve hole, the second passage, and the third passage, and when the differential pressure between the second passage and the third passage is larger than a set differential pressure. The pilot passage and the third passage are connected to form the auxiliary passage, and the differential pressure between the second passage and the third passage is greater than the set differential pressure. The pressure differential valve according to claim 4, further comprising a differential pressure valve that communicates the pilot passage and the second passage when they are small, and that blocks the pilot passage and the third passage to form the auxiliary passage. The control valve according to any one of the above. 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;
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 indoor evaporator;
A second refrigerant circulation passage capable of circulating so that refrigerant discharged from the compressor during heating operation returns to the compressor via the outdoor heat exchanger;
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,
An adjustment valve provided in the first refrigerant circulation passage, the opening degree of which is controlled to adjust the flow rate of the refrigerant flowing from the compressor to the indoor evaporator;
Provided in the second refrigerant circulation passage, provided in the third refrigerant circulation passage, a first valve whose opening degree is controlled to control a flow rate of the refrigerant flowing from the compressor to the outdoor heat exchanger, A composite valve integrally provided with a second valve whose opening degree is controlled to control the flow rate of the refrigerant flowing from the outdoor heat exchanger to the indoor evaporator;
A control unit that drives and controls each valve;
With
The composite valve is
The first passage connected to the discharge side of the compressor, the second passage connected to the outdoor heat exchanger, and the third passage connected to the inlet side of the indoor evaporator, the fluid between each passage A control valve capable of controlling the flow,
The first valve having a first valve body that opens and closes a first communication passage connecting the first passage and the second passage by contacting and separating from a first valve hole;
A second communication passage that connects the second passage and the third passage has a second valve body that opens and closes by contacting and separating from the second valve hole, and the second valve body is in a closed state; The first valve body can be operated independently, and the second valve body is connected to the first valve body so that the second valve body can operate integrally with the first valve body when the second valve body is open. The second valve;
When the first valve is opened, the first valve body is driven independently of the second valve body to adjust the opening degree of the first valve, while the first valve is closed when the first valve is closed. An actuator that integrally drives the body and the second valve body to adjust the opening of the second valve,
The controller is
When one of the first valve and the second valve is opened by driving and controlling the actuator, the other valve is closed so that one of the refrigerant of the second refrigerant circulation passage and the third refrigerant circulation passage is closed. Allow the flow of
When opening the second refrigerant circulation passage, the opening of each of the first valve and the regulating valve of the composite valve is controlled to flow from the compressor to the outdoor heat exchanger and the indoor evaporator. A vehicle air conditioner that adjusts a ratio of a flow rate of a refrigerant. In a pilot operated control valve capable of controlling the flow of refrigerant from the upstream side to the downstream side,
A main valve hole that communicates the upstream side passage and the downstream side passage, and a main valve body that can adjust its opening degree by contacting and separating from the main valve hole. A main valve provided to partition the downstream passage and the back pressure chamber;
A pilot valve hole that communicates one of the upstream side passage and the downstream side passage with the back pressure chamber, and a pilot valve body that can adjust its opening degree by contacting and separating from the pilot valve hole;
A leak passage having a smaller flow path cross-sectional area than the pilot valve hole, and communicating the other of the upstream side passage and the downstream side passage with the back pressure chamber;
A solenoid including a first iron core that moves in the axial direction integrally with the pilot valve body, and a second iron core that is disposed opposite to the first iron core via a gap in the axial direction;
An elastic member interposed between the main valve body and the pilot valve body and allowing relative displacement between the main valve body and the pilot valve body by expansion and contraction due to elastic deformation thereof;
With
In the energization control state of the solenoid, the main valve is controlled to a set opening degree by elastically deforming the elastic member so as to generate a load commensurate with a change in the attraction force of the solenoid. valve.   By forming the pilot valve hole larger than the leak passage, the amount of change in the pressure of the back pressure chamber with respect to the change in opening of the pilot valve is set to a predetermined value or more, whereby the deformation range of the elastic member is reduced. It is configured to be larger than the fluctuation range of the gap between the first iron core and the second iron core, and to make the stroke of the main valve body larger than the relative movement stroke between the first iron core and the second iron core. The control valve according to claim 9.

Images