JP5699263B2 - Control valve used in vehicle air conditioner - Google Patents

Description

  The present invention relates to a vehicle air conditioner and control valve, and more particularly to a control valve suitable for being provided downstream of an evaporator of a 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

  By the way, when a plurality of evaporators function depending on the operation state of the refrigeration cycle, it is necessary to ensure the dehumidifying performance by appropriately performing heat absorption by one evaporator and dehumidification by the other evaporator. is there. With regard to this point, it is conceivable to adjust the ratio of the evaporation amount of the refrigerant in each evaporator by making the evaporation pressure of one evaporator higher than the evaporation pressure of the other evaporator, by the differential pressure of the evaporation pressure. However, in order to maintain a stable control state, it is necessary to stably maintain the differential pressure of the evaporation pressure.

  The objective of this invention is ensuring the dehumidification performance stably in the vehicle air conditioner which has the driving | running state in which several evaporators function.

  In order to solve the above problems, a vehicle air conditioning apparatus according to an aspect of the present invention includes a refrigerant circulation passage including a first evaporator and a second evaporator, and is provided on the downstream side of the first evaporator. By adjusting the differential pressure between the upstream pressure and the downstream pressure of the control valve, the vehicle can execute an operation state in which the evaporation pressure of the first evaporator is made higher than the evaporation pressure of the second evaporator. A heating / cooling device, as a control valve, a valve body in which a force in the valve opening direction acts due to a differential pressure between the upstream pressure and the downstream pressure, and a drive that applies a force in the valve closing direction to the valve body by energization An electrically driven valve having a portion is provided.

  According to this aspect, by energizing the control valve provided on the downstream side of the first evaporator, the differential pressure between the upstream pressure and the downstream pressure can be adjusted, thereby the first evaporation. The differential pressure between the evaporation pressure of the evaporator and the evaporation pressure of the second evaporator can be adjusted. As a result, the ratio of the evaporation amount of the refrigerant in each evaporator can be adjusted by energizing the control valve, and the dehumidifying performance in the vehicle air conditioner can be kept good. Further, when the power supply to the control valve is turned off, even if the differential pressure before and after the pressure is small, the valve is quickly fully opened, so that pressure loss in the control valve can be suppressed and stable refrigerant circulation can be maintained. .

  Another aspect of the present invention is a control valve. The control valve is provided on the downstream side of the first evaporator in the vehicle air conditioner including the first evaporator and the second evaporator, and adjusts the differential pressure between the upstream pressure and the downstream pressure. This is a control valve that makes the evaporation pressure of the first evaporator higher than the evaporation pressure of the second evaporator, and a force in the valve opening direction acts due to the differential pressure between the upstream pressure and the downstream pressure. A valve body, and a drive unit that applies a force in the valve closing direction to the valve body when energized.

  If the control valve of this aspect is applied to a vehicle air conditioner, the differential pressure between the upstream pressure and the downstream pressure can be adjusted by energizing the control valve, whereby the first evaporator The differential pressure between the evaporation pressure of the second evaporator and the evaporation pressure of the second evaporator can be adjusted. As a result, the ratio of the evaporation amount of the refrigerant in each evaporator can be adjusted by energizing the control valve, and the dehumidifying performance in the vehicle air conditioner can be kept good. Further, when the power supply to the control valve is turned off, even if the differential pressure before and after the pressure is small, the valve is quickly fully opened, so that pressure loss in the control valve can be suppressed and stable refrigerant circulation can be maintained. .

  ADVANTAGE OF THE INVENTION According to this invention, in the vehicle air conditioning apparatus which has the driving | running state in which a some evaporator functions, the dehumidification performance can be ensured stably.

It is a figure showing the schematic structure and operation | movement of the vehicle air conditioner which concern on 1st Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 1st Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 1st Embodiment. It is sectional drawing showing the specific structure of the control valve which concerns on 2nd Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 3rd Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 3rd Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 4th Embodiment. It is sectional drawing showing the specific structure and operation | movement of a control valve concerning 4th Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
First, a first embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a schematic configuration and an operation of the vehicle air conditioning apparatus according to the first embodiment. The lower part of the figure shows the system configuration, and the upper part of the figure shows a Mollier diagram for explaining the operation of the refrigeration cycle. 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 (refrigerant circulation circuit) in which a compressor 2, an indoor condenser 3, an outdoor heat exchanger 5, an evaporator 7, and an accumulator 8 are connected by piping. 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 chlorofluorocarbon (HFO-1234yf) 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.

  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 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.

  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 introduced into the passenger compartment is warmed 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. When the outdoor heat exchanger 5 functions as an indoor evaporator, the refrigerant that has become low temperature and low pressure due to the passage through the expansion device (second proportional valve 42 described later) evaporates when passing through the outdoor heat exchanger 5. To do.

  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 the expansion device (first proportional valve 41 described later) evaporates when passing through the evaporator 7. The air introduced into the passenger compartment is cooled and dehumidified by the latent heat of vaporization. At this time, the cooled and dehumidified air is heated while passing through the indoor condenser 3.

  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.

  A first control valve 31 and a second control valve 32 are provided between the indoor condenser 3 and the outdoor heat exchanger 5. 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 adjusts the opening degree of the bypass passage 29 by adjusting the opening degree of the valve portion by supplying current. To do. In the present embodiment, an open / close valve (on / off valve) that opens and closes depending on whether or not energized is used as the second control valve 32, and the opening degree is adjusted by adjusting the valve opening time per fixed time according to the valve opening frequency. adjust. In a modification, you may comprise as a proportional valve or differential pressure valve which can adjust the opening area itself of a valve part.

  A first proportional valve 41 is provided between the outlet of the indoor condenser 3 and the inlet of the evaporator 7, and a second proportional valve 42 is provided between the outlet of the indoor condenser 3 and the inlet / outlet of the outdoor heat exchanger 5. Is provided. The first proportional valve 41 includes a valve portion that opens and closes the first branch passage 26 and an actuator that drives the valve portion. 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.

  Further, a third control valve 33 is provided between the outlet of the evaporator 7 and the inlet of the accumulator 8. The third control valve 33 includes a valve portion that opens and closes the return passage 30 and a solenoid that drives the valve portion, and adjusts the opening degree of the return passage 30 by adjusting the opening degree of the valve portion by supplying current. In the present embodiment, an on-off valve (on / off valve) that opens and closes depending on whether or not energized is used as the third control valve 33, and the opening degree is adjusted by adjusting the valve opening time per fixed time according to the valve opening frequency. adjust. In a modification, you may comprise as a proportional valve or differential pressure valve which can adjust the opening area itself of a valve part.

  The vehicle air conditioning apparatus 1 configured as described above is controlled by a control unit (not shown). The control unit calculates the control amount of each actuator 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 determines the control amount (valve opening degree and opening / closing state) of each control valve based on predetermined external information detected by various sensors such as the temperature inside and outside the vehicle interior and the temperature of air blown from the evaporator 7. Then, a current is supplied to the solenoid so that the control amount is realized. The control unit sets an ON / OFF duty ratio when supplying current to the second control valve 32 and the third control valve 33, and controls energization to each control valve according to the duty ratio. In the modification, an electric motor such as a stepping motor may be provided as an actuator for each control valve. In this case, the control unit sends a control pulse signal to the stepping motor so that the control amount of each control valve is realized. Output.

  Next, main operations of the refrigeration cycle of the present embodiment will be described. FIG. 1 illustrates a state of the vehicle air conditioning apparatus during specific heating operation. The “specific heating operation” here is an operation state in which the function of dehumidification is particularly enhanced in the heating operation. In the Mollier diagram in the upper part of the figure, the horizontal axis represents enthalpy and the vertical axis represents various pressures. Thick lines and arrows in the figure indicate the flow of the refrigerant, and symbols a to h correspond to those in the Mollier diagram. Further, “x” in the figure indicates that the flow of the refrigerant is blocked.

  As illustrated, during the specific heating operation, the first control valve 31 is closed, and the second control valve 32 and the third control valve 33 are opened. On the other hand, the first proportional valve 41 is opened. 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 is compressed by circulating through the refrigerant circulation passage so as to pass through the indoor condenser 3, the first proportional valve 41, the evaporator 7, the third control valve 33, and the accumulator 8. Returning to the machine 2, on the other hand, the compressor is circulated through the refrigerant circulation passage 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. Return to 2.

  That is, the high-temperature and high-pressure gas refrigerant discharged from the compressor 2 is condensed through the indoor condenser 3 (b point → c point). And it becomes a cold / low pressure gas-liquid two-phase refrigerant adiabatically expanded by the first proportional valve 41 (point c → point f), and evaporates in the evaporator 7 (point f → point g). 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 (d point → e point). 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.

  At this time, the control unit ratio of the refrigerant evaporation amount in the outdoor heat exchanger 5 and the refrigerant evaporation amount in the evaporator 7 in order to appropriately perform heat absorption by the outdoor heat exchanger 5 and dehumidification by the evaporator 7. Adjust appropriately. For this purpose, for example, the third control valve 33 is fully opened, and the second control valve 32 is set so that the differential pressure ΔP = Po−Pe between the evaporation pressure Po of the outdoor heat exchanger 5 and the evaporation pressure Pe of the evaporator 7 becomes appropriate. Open / close control. At this time, the evaporation pressure Pe is substantially equal to the suction pressure Ps of the compressor 2.

  That is, when the differential pressure ΔP increases, the evaporation amount in the outdoor heat exchanger 5 becomes relatively small (the evaporation amount in the evaporator 7 becomes relatively large). On the contrary, when the differential pressure ΔP decreases, the evaporation amount in the outdoor heat exchanger 5 becomes relatively large (the evaporation amount in the evaporator 7 becomes relatively small). The control unit ensures the dehumidifying function during the specific heating operation by controlling the differential pressure ΔP to be appropriate. In the present embodiment, the evaporation pressure Po of the outdoor heat exchanger 5 is specified by detecting the temperature To on the inlet side of the outdoor heat exchanger 5. Further, the pressure Pe at the outlet of the evaporator 7 is specified by detecting the temperature Te on the inlet side of the evaporator 7.

  Depending on the operating state, the evaporation pressure Pe of the evaporator 7 may be set higher than the evaporation pressure Po of the outdoor heat exchanger 5. In that case, the second control valve 32 is fully opened, and the third control valve is set so that the differential pressure ΔP = Pe−Po between the evaporation pressure Pe of the evaporator 7 and the evaporation pressure Po of the outdoor heat exchanger 5 becomes appropriate. 33 is controlled to open and close. At this time, the evaporation pressure Po is substantially equal to the suction pressure Ps of the compressor 2.

  In the present embodiment, the second control valve 32 and the third control valve 33 are configured as normally open solenoid valves that are opened when the solenoid is not energized. For this reason, when the above control is executed, it is desirable that the second control valve 32 and the third control valve 33 are in a fully open state so as not to cause flow resistance when the solenoid is not energized. In this embodiment, the 2nd control valve 32 and the 3rd control valve 33 are comprised as an electromagnetic valve which has a structure which can ensure such a fully open state.

  Next, specific configurations of the second control valve 32 and the third control valve 33 which are the main parts of the present embodiment will be described. 2 and 3 are cross-sectional views showing a specific configuration and operation of the control valve according to the first embodiment. In the present embodiment, since the second control valve 32 and the third control valve 33 have the same configuration, these will be described as the control valve 50.

  As shown in FIG. 2, the control valve 50 is configured by assembling a valve main body 102 that houses a valve mechanism therein and a solenoid 104 that drives the valve mechanism. An inlet port 110 connected to the upstream passage is provided at the center of the lower end of the body 105 in the valve body 102, and a lead-out port 112 connected to the downstream passage is provided at the side. A valve hole 114 is provided in the internal passage connecting the introduction port 110 and the outlet port 112, and a valve seat 116 is formed at the downstream opening end thereof.

  A bottomed cylindrical valve body 118 is disposed in the pressure chamber downstream of the valve hole 114. A plurality of legs are extended downward from the lower surface of the valve body 118. Since the leg portion is slidably inserted into the valve hole 114, a stable opening / closing operation in the axial direction of the valve body 118 is secured. A spring 120 that biases the valve body 118 in the valve opening direction is interposed between the valve body 118 and the body 105.

  On the other hand, the solenoid 104 is attached so as to seal the upper end opening of the body 105. The solenoid 104 includes a core 130 connected so as to seal the body 105, a bottomed cylindrical sleeve 132 that is received so as to fix the upper half of the core 130, and an axial direction of the core 130 within the sleeve 132. A plunger 134 disposed opposite to the sleeve 132, a bobbin 136 fitted to the sleeve 132, an electromagnetic coil 138 wound around the bobbin 136, and a case assembled to the core 130 so as to cover the electromagnetic coil 138 from the outside. 140.

  An upper end portion of a long cylindrical actuating rod 142 is press-fitted into the lower half portion of the plunger 134. The operating rod 142 extends downward from the plunger 134 and penetrates the core 130, and its tip abuts against the bottom of the valve body 118. The operation rod 142 operates integrally with the plunger 134 and the valve body 118. The plunger 134 has a cylindrical shape, and a communication path 144 is formed along the axial direction thereof. The communication path 144 communicates with a back pressure chamber 146 formed on the bottom side in the sleeve 132.

  A circular boss-shaped guide portion 148 extends downward from the center of the lower surface of the core 130, and the valve body 118 is slidably fitted on the guide portion 148. That is, the valve body 118 is stably supported while its upper half is guided by the guide part 148 and its lower half is guided by the valve hole 114. With such a configuration, the back pressure chamber 150 is defined between the valve body 118 and the core 130. A communication hole 119 for communicating the back pressure chamber 150 and the upstream pressure chamber is formed at the bottom of the valve body 118. Therefore, when the control valve 50 as shown in FIG. 3 is controlled, the back pressure chamber 150 is filled with the upstream pressure Pin.

  As shown in FIG. 2, the control valve 50 configured as described above has no spring force between the core 130 and the plunger 134 when the solenoid 104 is turned off (non-energized state). The valve 120 is urged in the valve opening direction to be fully opened. On the other hand, when the solenoid 104 is turned on (energized state) as shown in FIG. 3, a suction force acts between the core 130 and the plunger 134. 118. As a result, the valve body 118 operates in the valve closing direction.

In the present embodiment, by introducing the upstream pressure Pin into the back pressure chamber 150, an area where the differential pressure (Pin−Pout) between the upstream pressure Pin and the downstream pressure Pout acts in the valve opening direction in the valve body 118. (AB) is made smaller than the cross-sectional area A of the valve hole 114. As a result, the valve body 118 can be driven in the valve closing direction with a relatively small solenoid force. On the other hand, since the differential pressure (Pin−Pout) acts in the valve opening direction, when the solenoid 104 is turned off from the on state, the valve body 118 quickly operates in the valve opening direction. In the modification, the back pressure chamber 150 may not be formed by eliminating the guide portion 148 and the communication hole 119.
In the present embodiment, by adjusting the ratio of time between the energized state (ON) and the non-energized state (OFF) of the solenoid 104 of the control valve 50, that is, the ON / OFF duty ratio, The average differential pressure as a value can be controlled to an appropriate value.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The vehicle air-conditioning apparatus according to the present embodiment is different from the first embodiment in the configuration of the second control valve 32 and the third control valve 33, but is common in other 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. 4 is a cross-sectional view illustrating a specific configuration of the control valve according to the second embodiment. In the present embodiment as well, the second control valve 32 and the third control valve 33 have the same configuration, and therefore these will be described as the control valve 250.

  In the control valve 250, the introduction port 110 connected to the upstream passage is provided at the side of the body 105, and the outlet port 112 connected to the downstream passage is provided at the center of the lower end. A valve body 218 is disposed in the pressure chamber on the upstream side of the valve hole 114. The valve body 218 is configured to be larger than the valve body 118 of the first embodiment so that its inner diameter B is larger than the inner diameter A of the valve hole 114. Accordingly, the outer diameter of the guide portion 148 extending downward from the core 130 is also increased. A communication hole 220 for communicating the back pressure chamber 150 and the downstream pressure chamber is formed at the bottom of the valve body 218. For this reason, when the control valve 250 is controlled, the back pressure chamber 150 is filled with the downstream pressure Pout.

  When the solenoid 104 is turned off (non-energized state), the control valve 250 configured as described above is urged in the valve opening direction by the spring 120 and is fully opened. On the other hand, when the solenoid 104 is turned on (energized state), the solenoid force is transmitted to the valve body 218 via the operating rod 142, and the valve body 218 operates in the valve closing direction.

  In the present embodiment, as described above, by introducing the downstream pressure Pout into the back pressure chamber 150, the differential pressure (Pin−Pout) between the upstream pressure Pin and the downstream pressure Pout in the valve body 218 is the valve opening direction. The area (BA) acting on the valve hole 114 is smaller than the cross-sectional area A of the valve hole 114. Thereby, the valve body 218 can be driven in the valve closing direction with a relatively small solenoid force. On the other hand, since the differential pressure (Pin-Pout) acts in the valve opening direction, when the solenoid 104 is turned off from the on state, the valve body 218 quickly operates in the valve opening direction. Also in the present embodiment, by adjusting the ON / OFF duty ratio of the solenoid 104 of the control valve 250, the average differential pressure, which is the average value of the differential pressure before and after, can be controlled to an appropriate value.

[Third Embodiment]
The vehicle air-conditioning apparatus according to the present embodiment is different from the first embodiment in the configuration of the second control valve 32 and the third control valve 33, but is common in other 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. 5 and 6 are cross-sectional views showing a specific configuration and operation of the control valve according to the third embodiment. In the present embodiment as well, the second control valve 32 and the third control valve 33 have the same configuration, and therefore these will be described as the control valve 350.

  In the control valve 350, a stepped columnar transmission rod 340 (corresponding to a “transmission member”) is provided inside the valve body 118. The transmission rod 340 has a lower end penetrating the center of the valve body 118 and can be displaced relative to the valve body 118 in the axial direction. On the other hand, a locking ring 342 is fitted to the lower end portion of the transmission rod 340, and the relative displacement in the axial direction of the transmission rod 340 is restricted. A concave portion is formed at the center of the upper end portion of the transmission rod 340, and the lower end portion of the operating rod 142 is inserted and connected.

  A flange portion extending outward in the radial direction is provided at the upper end portion of the transmission rod 340, and a spring 344 that urges the valve body 118 in the valve closing direction is provided between the flange portion and the bottom portion of the valve body 118. It is intervened. When the solenoid 104 is turned on, the transmission rod 340 is displaced to the bottom dead center, so that a set load by the spring 344 is applied. The set differential pressure as the differential pressure valve is determined by the balance between the loads of the spring 344 and the spring 120. That is, in the control valve 350, the differential pressure valve in which the valve body 118 operates so that the differential pressure (Pin−Pout) between the upstream pressure Pin and the downstream pressure Pout becomes a set differential pressure set by the spring 344 and the spring 120. Function as.

That is, as shown in FIG. 5, the control valve 350 is urged in the valve opening direction by the spring 120 and is fully opened when the solenoid 104 is turned off (non-energized state). On the other hand, as shown in FIG. 6, when the solenoid 104 is turned on (energized state), the solenoid force is transmitted to the transmission rod 340 via the operating rod 142, and the transmission rod 340 is displaced to the bottom dead center. Accordingly, the valve body 118 is operated so that the differential pressure (Pin−Pout) between the upstream pressure Pin and the downstream pressure Pout becomes the set differential pressure. That is, since the transmission rod 340 and the valve body 118 are relatively displaceable, the valve body 118 has a force in the valve opening direction by the spring 120, a force in the valve closing direction by the spring 344, and a differential pressure (Pin−). The force in the valve opening direction due to Pout) is held at a balanced position. On the other hand, when the solenoid 104 is turned off from the on state, the force in the valve closing direction by the solenoid 104 does not act, so that the valve body 118 quickly moves in the valve opening direction by the biasing force of the spring 120.
In the present embodiment, the set differential pressure is adjusted by adjusting the time ratio between the energized state (ON) and the non-energized state (OFF) of the solenoid 104 of the control valve 350, that is, the ON / OFF duty ratio. Can be changed.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. Although the configurations of the second control valve 32 and the third control valve 33 are different from those of the first embodiment, the other portions are common. 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. 7 and 8 are cross-sectional views showing the specific configuration and operation of the control valve according to the fourth embodiment. In the present embodiment as well, the second control valve 32 and the third control valve 33 have the same configuration, and therefore these will be described as the control valve 450.

  The control valve 450 is driven by a motor unit 420 as an actuator. The upper end opening of the body 105 is sealed by the body 430 of the motor unit 420. The motor unit 420 is configured as a stepping motor including a rotor 432 and a stator 434. A valve operating body 436 is fitted to the lower end of the rotor 432. A male thread portion is formed on the outer peripheral surface of the valve operating body 436 and is screwed with a female thread portion formed on the inner surface of the lower end portion of the body 430. With such a configuration, the valve operating body 436 rotates in response to the rotational driving force of the motor unit 420, and converts the rotational force into a translational force.

  A guide portion 148 extends downward from the lower end surface of the body 430. The valve body 418 is slidably supported so that its upper half is inserted into the guide portion 148. A back pressure chamber 150 is formed between the valve body 418 and the body 430. A spring receiver 440 is disposed in the back pressure chamber 150 so as to contact the lower end surface of the valve operating body 436. A spring 442 that biases the valve body 418 in the valve closing direction is interposed between the spring receiver 440 and the valve body 418. A communication hole 446 for communicating the back pressure chamber 150 with the upstream pressure chamber is provided in the center of the bottom of the valve body 418.

  With such a configuration, the valve operating body 436 is displaced in the axial direction by rotation, and drives the valve body 418 in the opening / closing direction via the spring receiver 440 and the spring 442. The control unit calculates the number of drive steps according to the set opening, and supplies a drive current (drive pulse) to the excitation coil of the stator 434. As a result, the rotor 432 rotates, and the valve operating body 436 is rotationally driven as shown in FIG. 8 to adjust the opening of the control valve 450 to the set opening. As shown in FIG. 7, the valve body 118 can be surely fully opened by displacing the valve operating body 436 to the top dead center.

  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 embodiment, as shown in the lower part of FIG. 1, the control valve 50 (the second valve) is provided both on the downstream side of the evaporator 7 and on the downstream side of the outdoor heat exchanger 5 (when acting as an outdoor evaporator). Although the example which provides the control valve 32 and the 3rd control valve 33) was shown, you may make it provide only in the downstream of either evaporator. For example, the control valve 50 may be provided on the downstream side of the evaporator 7 and the control valve 50 may not be provided on the downstream side of the outdoor heat exchanger 5 (when acting as an outdoor evaporator).

  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, 5 Outdoor heat exchanger, 7 Evaporator, 8 Accumulator, 31 1st control valve, 32 2nd control valve, 33 3rd control valve, 41 1st proportionality Valve, 42 second proportional valve, 50 control valve, 102 valve body, 104 solenoid, 105 body, 110 introduction port, 112 lead-out port, 114 valve hole, 116 valve seat, 118, 218 valve body, 250 control valve, 340 transmission Rod, 350 control valve, 418 valve body, 420 motor unit, 430 body, 432 rotor, 434 stator, 436 valve operating body, 450 control valve.

Claims (2)

By providing a differential pressure between the upstream pressure and the downstream pressure provided on the downstream side of the first evaporator in the vehicle air conditioning system including the first evaporator and the second evaporator, A control valve for making the evaporation pressure of the first evaporator higher than the evaporation pressure of the second evaporator,
A body having an introduction port for introducing the refrigerant from the upstream side, a derivation port for deriving the refrigerant to the downstream side, and a valve hole provided in a passage connecting the introduction port and the derivation port;
A cylindrical guide provided in the body and extending coaxially with the valve hole;
It is slidably inserted into the guide part and has a bottomed cylindrical shape that can be opened and closed by moving in the axial direction so that the bottom part comes into contact with and separates from the valve hole, and the difference between the upstream pressure and the downstream pressure. A valve body in which a force in the valve opening direction acts by pressure,
Attached to said body, an actuator for applying a closing force to the valve body by energization,
Bei to give a,
The guide portion extends into a space surrounded by the actuator and the body;
A back pressure chamber surrounded by the valve body and the guide portion is formed,
A communication passage that communicates the valve hole and the back pressure chamber is formed at the bottom of the valve body, and refrigerant acting on the valve body by introducing upstream pressure to the back pressure chamber through the communication passage. Therefore, an area where the differential pressure between the upstream pressure and the downstream pressure acts in the valve opening direction in the valve body is smaller than the cross-sectional area of the valve hole. It is comprised so that it may become . The control valve characterized by the above-mentioned. 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;
  One of the first evaporator and the second evaporator functions as the outdoor evaporator, and the other of the first evaporator and the second evaporator functions as the indoor evaporator. 2. The control valve according to claim 1, which is applied to a vehicle air conditioner.

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