FR2884907A1 - REFRIGERATION CYCLE DEVICE FOR A VEHICLE - Google Patents

Abstract

A refrigeration cycle device for a vehicle includes a condition detection unit (9, 9a, 13, 13a, 12, 14 to 16, 18, 19, 21, 22) for detecting a condition in which an internal pressure of refrigerant cycle exceeds a control set pressure, and a pressure reduction unit for reducing a refrigerant pressure of a low pressure side of a refrigerant cycle when the condition is detected. For example, when the condition detecting unit detects the condition, the pressure detecting unit starts a compressor (8) of the refrigerant cycle so as to reduce the pressure of the low pressure side in the refrigerant cycle.

Description

REFRIGERATION CYCLE DEVICE FOR A VEHICLE

  FIELD OF THE INVENTION The present invention relates to a vehicle refrigeration cycle device using a refrigerant containing carbon dioxide (CO2) as the main component, for example.

  BACKGROUND OF THE INVENTION As a device of this type of refrigeration cycle devices, there is known a refrigeration cycle device equipped with a compressor, in which the delivery capacity of this compressor is variable. function of a control value applied externally from the outside and the pressure of the refrigerant can be increased to a supercritical range, a heat radiator for cooling the refrigerant compressed by the compressor, an expansion device for reducing the pressure of the refrigerant cooled by the heat sink, and an evaporator for evaporating the refrigerant whose pressure has been reduced by the expansion device. According to this refrigeration cycle device, when it is determined that a thermal load at the beginning of the launch of the device is greater than a predetermined load, the control value to be inputted from the outside is adjusted so that the discharge value of the compressor is caused to continuously vary from the minimum state to the maximum state over a predetermined time, whereby an abnormal increase in the high pressure can be reduced, even at the moment of launching of the refrigerant cycle under a heavy load, and thus one can prevent the pipes, etc., from being damaged (see for example JP-A-2002-71 228).

  In the refrigeration cycle device described above, the abnormal increase in high pressure is reduced by controlling the compressor output condition when the compressor is started, and there is no description on the timing of the control. compressor in the stopped state. In particular, in the refrigeration cycle device for a vehicle, in comparison with the increase of the refrigerant pressure due to the increase of the ambient temperature, such as the temperature of the outside air or the like, the increase the refrigerant pressure is more significantly affected by heat from an engine, etc., during a vehicle journey, so that the increase of the refrigerant pressure, when the compressor is in the stopped state, becomes a more serious problem.

  SUMMARY OF THE INVENTION The present invention has been implemented in view of the foregoing problem and is intended to provide a refrigeration cycle device for a vehicle that can reduce the increase in refrigerant pressure.

  In addition, it is another object of the present invention to provide a refrigeration cycle device for a vehicle that can reduce an excessive increase in refrigerant pressure by forcing a refrigerant cycle to operate even in the state where a driver does not issue any request to operate the refrigerant cycle.

  Still further, it is an additional object of the present invention to provide a refrigeration cycle device for a vehicle that can reduce the increase in refrigerant pressure due to back heating from an engine, an electric motor or other after the vehicle is stopped.

  Still further, it is an additional object of the present invention to provide a refrigeration cycle device for a vehicle that can reduce the pressure increase of a refrigerant cycle after stopping an engine serving as a source of force. driving the refrigerant cycle or the like by forcing the refrigerant cycle forcibly before the engine or the like is stopped.

  Still further, it is an additional object of the present invention to provide a refrigeration cycle device for a vehicle that can reduce the pressure increase of a refrigerant cycle even after stopping an engine, an engine electric or otherwise as a driving force source of the refrigerant cycle by allowing the refrigerant cycle to be controlled forcibly.

  In accordance with one aspect of the present invention, a vehicle refrigeration cycle device comprises a refrigerant cycle through which a refrigerant, a condition sensing unit for sensing a condition in which an internal pressure of the refrigerant cycle exceeds a control set pressure, and a pressure reduction means for reducing refrigerant pressure at the low pressure side of the refrigerant cycle when the condition is detected. As a result, an increase in refrigerant pressure due to heat from the engine or the like as the vehicle moves can be reduced and the vehicle equipment can be prevented from being damaged.

  For example, the control set pressure is set to a value lower than a set value which is set for a lowest resistance pressure in the refrigerant cycle. In this case, the functions of the respective functional parts of the refrigerant cycle can be guaranteed by setting the control setpoint pressure so that it is lower than the lowest resistance pressure set point in the cycle. refrigerant.

  The refrigerant cycle may include an overpressure device having a set pressure to protect equipment on the low pressure side in the refrigerant cycle. In this case, the control set pressure is set to be lower than the set pressure of the pressure relief device. The control set pressure can be set to be less than the setpoint pressure of the booster device to protect the equipment from the low pressure side of the refrigerant cycle by 0.5 MPa or more. When carbon dioxide is used as the main component of the refrigerant, the control set pressure is set in a range between 7 MPa and 12 MPa. In addition, the control set pressure can be set in anticipation of an increase in the pressure in the refrigerant cycle. In addition, the control set pressure can be set in anticipation of an increase in the pressure in the refrigerant cycle due to the residual heat of a vehicle engine after a vehicle ignition switch has been opened.

  When the refrigerant cycle comprises an overpressure device having a set pressure to protect equipment on the low pressure side in the refrigerant cycle, the control set pressure is set to be lower than the setpoint pressure of the device overpressure of 1.0 MPa or more.

  In general, the refrigerant cycle includes a compressor for compressing the refrigerant, a gas cooling device for cooling the refrigerant discharged from the compressor, and a cooling fan for blowing air to the gas cooling device. . In this case, the pressure reducing means starts at least one of the cooling fan and the compressor through a control unit when the condition detection unit detects the condition, and reduces the refrigerant pressure. the low pressure side in the refrigerant cycle. As a result, the refrigerant pressure due to a condition of the environment can be effectively reduced.

  As a compressor, a variable displacement compressor can be used. In this case, the pressure reducing means starts the variable displacement compressor while a discharge capacity of the variable displacement compressor is controlled by the control unit when the condition detection unit detects the condition.

  The pressure reducing means may start the compressor when the condition detection unit detects the condition while the vehicle engine is operating in a state where a vehicle ignition switch has been closed.

  Alternatively, the compressor may be constructed as an electrically controlled electric compressor. In this case, the condition detection unit detects the condition in a state where a vehicle ignition switch has been opened.

  The refrigerant cycle may be provided with a compressor for compressing a refrigerant, a gas cooling device for cooling the refrigerant discharged from the compressor, an evaporator for evaporating a refrigerant after it has been decompressed. , a first fan for blowing air to the gas cooling device, and a second fan for blowing air to the evaporator. In this case, when the condition detecting unit detects the condition, at least one of the first fan and the compressor is driven and the second fan is stopped by the control unit.

  The condition detection unit may include a pressure sensing unit for detecting whether the refrigerant pressure in the refrigerant cycle reaches a predetermined value. For example, the pressure sensing unit is a discharge pressure sensor for detecting refrigerant pressure on the discharge side of the compressor in the refrigerant cycle.

  Alternatively, the condition detection unit may include a first temperature sensing unit for detecting whether a refrigerant temperature in the refrigerant cycle reaches a predetermined value. In this case, the first temperature sensing unit comprises a discharge temperature sensor for detecting a refrigerant temperature on the discharge side of the compressor of the refrigerant cycle. In addition, the first temperature sensing unit may comprise at least one of a post-evaporation temperature sensor for detecting a temperature of the air that has passed through the evaporator of the refrigerant cycle, a fin temperature sensor for detecting the temperature of an evaporator fin and an air blowing temperature sensor for detecting the temperature of the air to be blown into the passenger compartment of the vehicle.

  In addition, the condition detection unit may include a second temperature sensing unit for detecting whether any of a temperature in the engine compartment of the vehicle and a temperature in the passenger compartment of the vehicle reaches predetermined value. For example, the second temperature sensing unit determines the temperature of the passenger compartment based on at least one of the detection values of an indoor air temperature sensor for directly sensing the temperature of the passenger compartment. air in the passenger compartment, an outdoor air temperature sensor for indirectly detecting the temperature in the passenger compartment, and a solar radiation temperature sensor for detecting a quantity of solar radiation entering the room; cockpit. Alternatively, the second temperature sensing unit determines, based on the sensing value of any of a motor water temperature and an engine intake air temperature, whether the temperature in the engine compartment reaches the predetermined value.

  In the present invention, the condition detecting unit may be provided with a stopping time detecting unit for detecting whether a compressor off time of the refrigerant cycle reaches a predetermined time.

  In accordance with another aspect of the present invention, the control unit starts at least one of a cooling fan for blowing air to a gas cooling device, and a compressor of the cooling cycle. refrigerant when the condition detection unit detects the condition, and then the control unit stops at least one of the compressor and the cooling fan during operation when a predetermined time has elapsed. As a result, the purpose described above can be achieved.

  Alternatively, the control unit initiates at least one of the cooling fan for blowing air to the gas cooling device and the refrigerant cycle compressor when the condition detection unit detects the condition. , and then the control unit stops at least one of the compressor and the cooling fan during operation when the control unit determines that the refrigerant pressure in the refrigerant cycle is less than or equal to a predetermined value .

  Alternatively, the control unit initiates at least one of the cooling fan for blowing air to the gas cooling device and the refrigerant cycle compressor when the condition detection unit detects the condition. , and then the control unit stops at least one of the compressor and the cooling fan during operation when the control unit determines that the refrigerant temperature in the refrigerant cycle is less than or equal to a predetermined value or any of a post-evaporation temperature, a fin temperature, and an air blowing temperature is less than or equal to a predetermined value.

  Alternatively, the control unit initiates at least one of the cooling fan for blowing air to the gas cooling device, and the compressor of the refrigerant cycle when the condition is detected, and then the control unit stops at least one of the compressor and the cooling fan during operation when the control unit determines that a temperature in the engine compartment of the vehicle or a temperature in the passenger compartment of the vehicle is less than or equal to at a predetermined value.

  Even in these cases, when a predetermined time elapses after at least one of the compressor of the refrigerant cycle and the cooling fan is stopped, the condition detection unit starts the detection. Alternatively, when the control unit determines that the refrigerant pressure in the refrigerant cycle is less than or equal to a predetermined value, after at least one of the compressor and the cooling fan is stopped, the unit condition detection starts the detection. Alternatively, when the control unit determines that any of the coolant temperature in the refrigerant cycle reaches a predetermined value or that the post-evaporation temperature, the fin temperature and the blast temperature of air reaches a predetermined value after at least one of the compressor and the cooling fan is stopped, the condition detection unit starts the detection.

  Alternatively, when the control unit determines that the temperature in the engine compartment of the vehicle or a temperature in the passenger compartment of the vehicle is less than or equal to a predetermined value after at least one of the compressor and the fan of the vehicle. cooling is stopped, the condition detection unit starts the detection.

  In the refrigerant cycle device, the refrigerant cycle can use refrigerant containing carbon dioxide as the main component.

BRIEF DESCRIPTION OF THE DRAWINGS

  The objects, features, and advantages of the present invention, as well as others, will become more apparent from the following detailed description of preferred embodiments made with reference to the accompanying drawings, in which: Figure 1 is a diagram showing The design of a refrigeration cycle device for a vehicle according to a first embodiment of the present invention. FIG. 2 is a timing diagram showing the variation of the refrigerant pressure in a refrigerant cycle when a compressor is controlled. in the vehicle refrigeration cycle device according to the first embodiment, Fig. 3 is a process control flow chart of controlling the compressor on the basis of a refrigerant pressure sensing value to reduce a pressure of refrigerant in the vehicle refrigeration cycle device according to FIG. 4 is a timing diagram showing the variation of refrigerant pressure of the refrigerant cycle when a cooling fan is controlled in the vehicle refrigeration cycle device according to the first embodiment, FIG. 5 is a process control flowchart of controlling the cooling fan based on the refrigerant pressure sensing value to reduce the refrigerant pressure in the vehicle refrigeration cycle device according to the first embodiment, Fig. 6 is a timing chart showing the variation of the refrigerant pressure in the refrigerant cycle when the cooling fan and the compressor are controlled in the vehicle refrigeration cycle device according to the first embodiment, Fig. 7 is a flowchart. command representing the tra it is to control the cooling fan and the compressor on the basis of the refrigerant pressure sensing value to reduce the refrigerant pressure in the vehicle refrigerant cycle according to the first embodiment, Fig. 8 is a diagram Fig. 9 is a diagram showing the design of another vehicle refrigeration cycle device according to the second embodiment of the present invention. Fig. 10 is a diagram showing the design of the controlled vehicle refrigeration cycle device based on various types of data associated with an engine in the vehicle refrigeration cycle device of the second embodiment, Fig. 11 is a chronogram representing the relationship between the variation of the temperature of the ref or the various types of temperature monitored and the variation of the refrigerant pressure in the vehicle refrigeration cycle device according to the second embodiment, Fig. 12 is a control flow chart showing the process of controlling the compressor on the basis of various types of temperature data to reduce the refrigerant pressure in the vehicle refrigeration cycle device according to the second embodiment, Fig. 13 is a control flow chart showing the processing when the compressor, etc., are stopped on the basis of the refrigerant pressure sensing value in the vehicle refrigerant cycle devices according to the first, second and third embodiments of the present invention, Fig. 14 is a control flow chart showing the processing of stop the compressor, etc., based on the div FIGS. 15 is a control flow chart showing the processing of determining a start time of detection of a unit. FIGS. condition detection system based on the lapse of time in the vehicle refrigeration cycle devices according to the first, second and third embodiments; Fig. 16 is a control flow chart showing the timing processing; detection start of the condition detecting unit based on the detection value of the refrigerant pressure in the vehicle refrigeration cycle devices according to the first, second and third embodiments, Fig. 17 is a control flow chart showing the processing of determining the start time for detecting the condition detection unit based on various types of temperature data in the vehicle refrigeration cycle devices according to the first, second and third embodiments, Fig. 18 is a control flow chart showing the processing of controlling an electrically driven compressor based on the refrigerant pressure sensing value to reduce the refrigerant pressure when an ignition switch is in an open state in the vehicle refrigeration cycle device according to the third embodiment, Fig. 19 is a control flow chart showing the process of controlling an electrically driven cooling fan based on the detection value of the refrigerant pressure to reduce the refrigerant pressure in the state where the ignition switch is o Fig. 20 is a control flow chart showing the process of controlling the electrically driven cooling fan based on the various types of temperature data when the ignition switch is in the open state, and Fig. 21 is a control flow chart showing the process of controlling the electrically driven cooling fan based on the elapsed time to reduce the refrigerant pressure when the ignition switch is in the closed state.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

  Preferred embodiments in accordance with the present invention will be described below with reference to the accompanying drawings.

  (First Embodiment) A refrigeration cycle device for a vehicle according to a first embodiment performs an inherent control to reduce the refrigerant pressure in a refrigerant cycle using a carbon dioxide (CO2) refrigerant. as the main component, so that parts of the refrigerant cycle can be prevented from being damaged due to the increase of the refrigerant pressure. In particular, the refrigeration cycle device for a vehicle is specific and different from a fixed refrigeration cycle device in which the increase of the refrigerant pressure is significantly affected by the heat that occurs when Vehicle engine is controlled differently.

  To solve the problem under such a particular condition, the vehicle refrigeration cycle device of this embodiment is controlled by taking into account the effect of heat that occurs when the vehicle is traveling. In particular, a factor causing the increase of the refrigerant pressure in the refrigerant cycle, which applies to the environment of the vehicle, is as follows. That is, when the vehicle is stopped or when the engine is stopped after the engine has been operating for a long time in a high-load state, such as a high-speed driving condition or the like, and therefore introduction of cooling air into the engine compartment is stopped or reduced, the heat of the engine block or the exhaust pipe is diffused into the engine compartment (space where the engine is mounted) and therefore the parts of the cycle device refrigerators are heated, so that the temperature of the refrigerant is increased.

  In a supercritical refrigerant cycle using carbon dioxide (CO2) as the main component, as is the case in this embodiment, the refrigerant cycle refrigerant is in a supercritical state due to heat radiation from the side of the refrigerant cycle. motor compartment, heat preservation, increase of outside air temperature, etc., due to the displacement of the vehicle at a time when the cycle is stopped, and the pressure in the cycle is increased, from so that the pressure can exceed the parts resistance pressure of the low pressure side. As a result, a pressure relief device is provided on the low pressure side, i.e., for example, on the suction side of the compressor.

  Here, the first embodiment will be described below with reference to FIGS. 1-7.

  Fig. 1 is a diagram showing the design of the vehicle refrigeration cycle device according to this embodiment. As shown in FIG. 1, the refrigerant cycle 1 is equipped with a compressor 8, a discharge pressure sensor 9, as a first example of a pressure detection unit for detecting the refrigerant pressure. on the high pressure side, a gas cooling device 3, corresponding to a heat exchanger on the high pressure side, an expansion valve 4 serving as a pressure reduction unit, an evaporator 5 corresponding to a low pressure side heat exchanger 9a, a low pressure side pressure sensor for detecting the refrigerant pressure of the low pressure side of the refrigerant cycle, an accumulator 6 for separating the refrigerant into a refrigerant; refrigerant in the gas phase and in a liquid phase refrigerant and supplying the gas-phase refrigerant to the suction part of the compressor 8, and a booster device 7 arranged on the bass side e pressure, which corresponds to the side of the suction portion of the compressor 8, which are successively connected in a ring manner to each other through pipes.

  At least one of the compressor 8, the gas cooling device 3, the evaporator 5 and the accumulator 6 constituting the vehicle refrigerant cycle is disposed in an engine compartment (engine mounting space). In addition, the gas cooling device 3 is provided with a cooling fan 2 so as to be opposed to each other.

  The compressor 8 is driven by a mutually locked belt with the motor to compress the gas phase refrigerant sucked from the accumulator 6 under the critical pressure or more and discharge the compressed refrigerant. The compressor 8 is controlled by a controller 10 (ECU) described later, and the rotation of the compressor 8 is driven by the motor or driven electrically by a battery mounted on the vehicle. The compressor 8 may be a variable displacement compressor. In this

  In this case, the controller 10 controls the current supplied to the variable displacement compressor to control the delivery capacity of the variable displacement compressor, thereby controlling the refrigerant pressure.

  The discharge pressure sensor 9 is arranged between the compressor 8 and the gas cooling device 3, and detects the refrigerant pressure in the refrigerant cycle 1. The detection value of the discharge pressure sensor 9, when the compressor 8 is stopped, is transmitted to the controller 10. When the detection value is about to exceed a predetermined control setpoint pressure of the refrigerant cycle 1, to reduce the refrigerant pressure, the controller 10 starts the operation of the compressor 8 to cause the refrigerant to circulate in the cycle to thereby reduce the refrigerant pressure, as an example of the pressure reduction unit.

  The control set pressure can be set to a value lower than the lowest resistance pressure set point in the refrigerant cycle 1 or to a value lower than the set pressure of the pressure relief device 7 intended to protect the refrigerant. 'equipment. In addition, instead of the compressor 8, the cooling fan 2 can be started to cool the gas cooling device 3, thereby cooling the refrigerant in the gas cooling device 3, so that it can be avoided. that the internal pressure of the refrigerant cycle does not increase. The control set pressure is set to a correct value in anticipation of the increase of the pressure in the refrigerant cycle taking into account the variation of the pressure increase in the refrigerant cycle in accordance with the specification of the refrigerant cycle. refrigerant mounted in the vehicle.

  When the vehicle is stopped and in addition the engine is also stopped after the vehicle has driven under a heavy load of the engine (high speed, uphill or other displacement), at a high outside air temperature, the temperature in the engine compartment is increased, and the pressure increase of 0.5 MPa or more may occur in the refrigerant cycle 1. Accordingly, the control set pressure is preferably set to a value lower than the control pressure of the overpressure device 7 for protecting the equipment on the low pressure side of the refrigerant cycle 1 of 0.5 MPa or more.

  The command set pressure is preferably set taking into account the tolerance of the pressure relief device 7. For example, when the pressure value of the pressure relief device is equal to 11 MPa and the tolerance is equal to 0, 5 MPa, the command setpoint is set to 10.5 MPa or less.

  In addition, it has been verified by means of on-board tests that the maximum pressure increase of the refrigerant cycle is equal to about 1.0 MPa, and therefore the command set pressure is preferably set to a value below the set pressure of the pressure relief device 7 of 1.0 MPa or more. For example, when the set pressure value of the booster device 7 is equal to 11 MPa, the control set pressure is set to 10.0 MPa or less.

  In addition, the control set pressure is preferably set in the range of 7 to 12 MPa, which is less than the set pressure of the booster device 7 of 0.5 MPa or more. 7 MPa is the refrigerant pressure at ambient temperature of the refrigerant cycle of approximately 30 C when the density of refrigerant enclosed in the refrigerant cycle is considered from the enclosed quantity of refrigerant. In the case where the control set pressure is set to 7 MPa or less, when the engine is started at an outside temperature of 30 C or less, the compressor starts operation absolutely. However, it may be considered a situation that a certain passenger launches the air conditioner only if the outside air temperature is equal to a level of about 30 C. Therefore, if the set pressure of control is set to 7 MPa or less, the compressor begins to be implemented against the intention of the passenger, which causes a deterioration of the fuel consumption of the vehicle. Therefore, to avoid such a situation, the command set pressure is preferably set to 7 MPa or more.

  The gas cooling device 3 exchanges heat with the high pressure / high temperature refrigerant discharged from the compressor 8 with air blown from the cooling fan 2, so that the refrigerant is condensed and liquefied.

  The cooling fan 2 cools the gas cooling device 3, and is constituted by an electrically driven cooling fan, a coupling fan of the direct coupling type to the motor or a fan driven by a hydraulic drive motor. The cooling fan 2 may be designed to also be used as a radiator cooling fan or be used exclusively for the gas cooling device 3. In addition, the cooling fan 2 may be fixedly secured to the cooling device of the radiator. gas 3, or attached to a part of the vehicle side.

  The expansion valve 4 is a pressure reduction unit for isenthalpically reducing the pressure of the refrigerant leaving the gas cooling device 3 depending on the degree of opening of the valve. In particular, the pressure of the refrigerant is reduced to a greater extent by reducing the degree of opening of the valve. The expansion valve 4 mechanically controls the refrigerant pressure on the high pressure side based on the refrigerant temperature at the outlet of the gas cooling device.

  The evaporator 5 is cooled by the gas cooling device 3, and it serves as a heat exchanger in which the liquid refrigerant maintained in the low temperature and low pressure state by the expansion valve 4 is evaporated by absorbing the heat of the outside air. The air passing through the evaporator 5 gives up its heat and is thus cooled, and the air is humidified as well. The cooled and dehumidified air is supplied as cooling air into the passenger compartment of the vehicle by a blower (not shown).

  The accumulator 6 subjects the refrigerant leaving the evaporator 5 to a gas-liquid separation, so that only the refrigerant in the gas phase is sucked into the compressor 8, and the accumulator 6 also serves as a receiver for accumulating the refrigerant additional in the refrigerant cycle.

  The overpressure device 7 serves to perform a discharge so that the internal pressure of the cycle does not exceed the design pressure of the low pressure side parts, not only the high pressure side, but also the low pressure side. For example, a type of valve is used as a booster device 7 in the refrigeration cycle using carbon dioxide (CO2) refrigerant.

  The operation of the ignition switch 11, the detection value of the discharge pressure sensor 9, the detection value of the pressure sensor of the low pressure side 9a, the operating state of the compressor 8 and the condition The operation of the cooling fan 2 is inputted to the controller 10 as a control unit of this embodiment, and the operation of an air conditioner switch (not shown) is also inputted to the controller 10. The controller 10 is equipped with a timer 12, and it can count the elapsed time, etc., of the driving or stopping state of each part constituting the refrigerant cycle 1. The controller 10 controls the compressor 8, the cooling fan 2, etc., based on various types of input data and preset programs.

  In Fig. 1 of this embodiment, the refrigeration cycle device is equipped with both the discharge pressure sensor 9 corresponding to an example of the pressure sensing unit for detecting the high side refrigerant pressure. pressure and the low pressure side pressure sensor 9a for detecting refrigerant pressure at the low pressure side, however, the refrigeration cycle device may be equipped with any of the sensors as a pressure sensing means in the extent to which it has the action and effect of the present invention.

  Next, the operation of the vehicle refrigeration cycle device according to this embodiment will be described. The main operation of the vehicle refrigeration cycle device is performed in the state where the ignition switch (IG) is closed or in the state where the engine is driven and also the compressor for the refrigerant cycle stopped.

  A pressure reduction process of reducing the refrigerant pressure is performed when a condition detecting unit detects certain conditions and a pressure reducing unit is actuated, a stopping condition detecting processing is performed, and then a pressure reduction cancel process of stopping the pressure reduction operation of the pressure reducing unit is performed. After that, a reset process is executed until the condition detection unit starts the detection, and then the process returns to the pressure reduction process.

  First, a case where the compressor 8 is started together with the pressure reducing unit, when the condition detecting unit detects a condition such that the pressure exceeds the control setpoint pressure of the cycle. refrigerant, will be described with reference to Figures 2 and 3.

  FIG. 2 is a timing chart showing the variation of the refrigerant pressure in the refrigerant cycle 1 when the compressor 8 is controlled and FIG. 3 is a flowchart showing the control process when the compressor 8 is controlled on the basis of a refrigerant pressure sensing value to reduce the refrigerant pressure (subroutine A). In FIG. 2 and other figures, the letter P (overpressure) indicates the pressure set point of the pressure relief device 7.

  As shown in FIG. 3, firstly, when the ignition switch (IG) is closed or the motor is driven (step S100), it is determined whether the compressor 8 is stopped or not (step Slll). When the compressor 8 is driven, a certain difference appears between the refrigerant pressure of the high pressure side of the refrigerant cycle 1 and the refrigerant pressure of the low pressure side of the refrigerant cycle 1 (see FIG. 2).

  If it is determined in step S111 that the compressor 8 is not stopped, the determination of step S111 is repeated again. In this case, if it is determined that the compressor 8 is stopped, the detection of the condition detection unit is started after a predetermined time t1 ', thereby executing the reset processing. At this time, the difference that appears between the refrigerant pressure of the high pressure side in the refrigerant cycle 1 and the refrigerant pressure of the low pressure side in the refrigerant cycle 1 is reduced with the lapse of time since the shutdown. compressor 8, and finally the two refrigerant pressure values become equal. Then, the refrigerant pressure thus made equal is increased by the radiation of the heat coming from the engine compartment, the conservation of the heat, etc., because of the operation of the engine during the time of travel of the vehicle or other (see Figure 2).

  It is determined in step S112 whether the refrigerant pressure P based on the detection of the discharge pressure sensor 9 is above a predetermined value P '. If it is determined that the refrigerant pressure reaches the predetermined value P ', the processing of starting compressor 8 (step S113) is executed. If it is determined that the refrigerant pressure P does not reach the predetermined value P ', the determination of the step S112 is repeated again. At this time, the refrigerant pressure in the refrigerant cycle 1 is divided into that of the high pressure side and that of the low pressure side in association with the compressor drive 8, and a pressure difference occurs between the two values of refrigerant pressure (see Figure 2).

  In addition, after the compressor 8 has been started, counting of a timer t2 is started by the timer 12 (step S114). In step 5115, counting of timer t2 continues until it reaches t2 'and, if it is determined that count of timer t2 reaches t2', compressor 8 in operation is stopped (step S116 ). With regard to the refrigerant pressure in the refrigerant cycle 1, a pressure difference occurring between that of the high pressure side and that of the low pressure side is reduced because the refrigerant pressure at the high pressure side is reduced and the The refrigerant pressure of the low pressure side is increased in association with the stopping of the compressor 8. As a result, both the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side become equal, and thus the pressure of refrigerant is made uniform. As a result, the refrigerant pressure is controlled to a value below the control set pressure taken globally (see Figure 2).

  After that, the processing proceeds to the bound processing indicated by a link mark K in Fig. 3 to advance to a determination of step S155 of Fig. 16 or a determination of step S160 of Fig. 17 shown in a second embodiment, whereby the processing proceeds to a step of initiating the detection of the condition detecting unit.

  As described above, if the refrigerant pressure in the refrigerant cycle 1 is kept below the control set pressure, the equipment of the refrigerant cycle 1 can be prevented from being damaged. However, when the refrigerant pressure in the refrigerant cycle 1 is likely to be in the condition where it exceeds the control set pressure due to the effects of the outside air temperature, heat radiation from the engine compartment , heat storage, etc., because of the operation of the engine during the vehicle travel time or the like, the processing of step S113 is performed again and the compressor 8 is started so as to prevent the refrigerant cycle equipment 1 is damaged.

  The control set pressure is a pre-programmed predetermined value in the controller 10, and it can be set to a value lower than the lowest resistance pressure in the refrigerant cycle 1 or to a value lower than the set pressure of the refrigerant cycle. pressure relief device 7. The pressure relief device 7 is arranged on the low pressure side of the refrigerant cycle 1, and in this case the pressure setpoint of the pressure relief device 7 corresponds to the operating pressure that can be guaranteed for the equipment. provided on the low pressure side of the refrigerant cycle 1, which covers the zone extending from the downstream side of the expansion valve 4 to the suction part of the compressor 8.

  In addition, the set pressure has a constant range because the discharge must operate safely, and it represents a pressure range in which the overpressure will be expelled. This value is established taking into account the tolerance of the overpressure, the effect of the variation by aging of the device, etc. For example, in the case where the set pressure is equal to 11 MPa, when the product tolerance is equal to 0.5 MPa and the deviation of the set value due to the variation due to aging is equal to 0 , 5 MPa, the pressure reduction unit operates under a pressure of at least less than 10 MPa.

  In addition, the compressor 8 may be a variable displacement compressor, and when the condition is detected, the controller 10 may control the capacity of the variable displacement compressor to start the compressor. This is done to prevent a rapid increase in refrigerant pressure on the high pressure side. In particular, at the initial stage of the drive, the variable displacement compressor is driven by applying a certain current value to the compressor, and thereafter the capacity of the compressor is varied while the delivery pressure is controlled. by feedback. In addition, when an electrically driven compressor is used, the same effect can be achieved by controlling the rotational speed of the motor.

  Then, a case where the cooling fan 2 is launched in place of the launch of the compressor 8, when the condition is detected, will be described. Fig. 4 is a timing chart showing the variation of the refrigerant pressure in the refrigerant cycle when the cooling fan 2 is controlled. Fig. 5 is a flowchart showing the control process of controlling the cooling fan 2 based on the refrigerant pressure sensing value to reduce the refrigerant pressure (subroutine B).

  As shown in Fig. 5, firstly, when the ignition switch (IG) is closed or the engine is running (step S100), it is determined whether the compressor 8 is stopped or not (step S111). ). When the compressor is driven, the refrigerant pressure in the refrigerant cycle 1 has some difference between the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side (see Figure 4).

  If it is determined in step 5111 that compressor 8 is not stopped, the determination of step S111 is repeated again. If it is determined in step S111 that the compressor 8 is stopped, after a predetermined time tl 'described later, the detection of the condition detection unit is started, thereby executing the reset processing. At this time, the difference that appears between the refrigerant pressure of the high pressure side and the refrigerant pressure of the low pressure side in the refrigerant cycle 1 is reduced with the lapse of time from the stopping of the compressor 8, and the two values of refrigerant pressures are finally equal (i.e., the refrigerant pressure is made uniform).

  It is determined in step S112 whether the refrigerant pressure P based on the detection of the pressure of the delivery sensor 9 is above a predetermined value P '. Then, the thus made uniform refrigerant pressure P is increased by heat radiation from the engine compartment, heat preservation, etc. , because the engine starts when the vehicle is moving or otherwise (see Figure 4).

  If it is determined that the refrigerant pressure P reaches the predetermined value P ', the treatment constituting to start the cooling fan 2 is executed (step S117). If it is determined that the refrigerant pressure P does not reach the predetermined value P ', the determination of the step S112 is repeated again. The refrigerant pressure P in the refrigerant cycle 1 is controlled so that it is lower than the predetermined value P ', because the refrigerant is cooled by the launch of the cooling fan 2 (refer to FIG. Figure 4). In addition, after the cooling fan 2 has been started, the countdown of the timer t2 is started by the timer 12 (step S114).

  In step S115, counting of timer t2 is continued until the count value reaches t2 ', and if it is determined that count of timer t2 reaches t2', cooling fan 2 in operation is stopped (step S118). The refrigerant pressure in the refrigerant cycle 1, which has been lower than the predetermined value P ', begins to increase gradually again due to the effect of the outside air temperature and the heat radiation from the compartment engine, heat preservation, etc., due to the operation of the engine at the time of the vehicle or other displacement in association with the shutdown of the compressor 8 (see Figure 4).

  After that, the processing proceeds to the bound processing indicated by the link mark K in Fig. 3 to proceed to a determination of step 5155 of Fig. 16 or a determination of step S160 of Fig. 17 shown in Fig. the second embodiment, whereby the processing proceeds to a step of initiating the detection of the condition detecting unit.

  As described above, if the refrigerant pressure in the refrigerant cycle 1 is kept below the control set pressure, the equipment of the refrigerant cycle 1 can be prevented from being damaged. However, when the refrigerant pressure in the refrigerant cycle 1 is likely to be in the condition where it exceeds the control set pressure due to the effects of the outside air temperature, heat radiation from the compartment motor, heat preservation, etc., because of the operation of the engine at the time of the vehicle movement or the like, the treatment of the step S117 is performed again and the cooling fan 2 is started so as to prevent that refrigerant cycle equipment 1 is damaged.

  The cooling fan 2 may be a variable type fan, and when the condition is detected, the controller 10 may control the input to the variable type cooling fan to start the cooling fan. This is done to help reduce the refrigerant pressure more efficiently. In particular, at the initial stage of the cooling fan drive, a certain input value is inputted to the cooling fan 2 to start the cooling fan, and then the input value is caused to vary while the discharge pressure is subjected to a feedback control, thus controlling the speed of rotation of the cooling fan 2.

  At the condition detection time, the controller 10 preferably stops the blower for blowing air to the evaporator 5 in addition to launching at least one of the cooling fan 2 and the compressor 8 for the cycle refrigerant.

  Next, a case where the cooling fan 2 and the compressor 8 are driven stepwise at the time of condition detection will be described.

  Fig. 6 is a flowchart indicating the variation of the refrigerant pressure in the refrigerant cycle when the cooling fan 2 and the compressor 8 are controlled. Fig. 7 is a flowchart showing the control process of controlling the cooling fan 2 and the compressor 8 based on the refrigerant pressure sensing value to reduce the refrigerant pressure (subroutine C).

  As shown in Fig. 7, firstly, when the ignition switch (IG) is closed or the engine is running (step S100), it is determined whether the compressor 8 is stopped (step S111). When the compressor 8 is driven, the refrigerant pressure in the refrigerant cycle 1 has some difference between the high-side refrigerant pressure and the low-side refrigerant pressure (see Fig. 6).

  If it is determined in step S111 that the compressor 8 is not stopped, the determination of step S111 is repeated again. If it is determined that the compressor 8 is stopped, after a predetermined time tl ', described later, has elapsed, the detection of the condition detection unit is started, thereby executing the reset processing. At this time, the difference that appears between the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side is progressively reduced with the lapse of time from the compressor stop 8, and the two values refrigerant pressures are finally equal to each other.

  It is determined in step S120 whether the refrigerant pressure P based on the detection of the discharge pressure sensor 9 is above a predetermined value P1. Then, the refrigerant pressure P thus made uniform is increased by the heat radiation from the engine compartment, heat preservation, etc., due to the operation of the engine at the time of the vehicle travel or the like (see FIG. 6).

  If it is determined that the refrigerant pressure P reaches the predetermined value P1, the treatment of starting the cooling fan 2 is executed (step S121). If it is determined that the refrigerant pressure P does not reach the predetermined value P1, the determination of the step S120 is repeated again. At this time, when a sufficient cooling effect can not be achieved even by starting the cooling fan 2, and the refrigerant pressure P in the refrigerant cycle 1 further increases above the predetermined value P1, the condition detecting unit executes the pressure determination on the basis of the detection value from the discharge pressure sensor 9 (see Figure 6).

  Then, it is determined in step S122 whether the refrigerant pressure P is greater than or equal to a predetermined value P2. If it is determined that the refrigerant pressure reaches the predetermined value P2, the processing of starting compressor 8 is performed (step S123). The predetermined value P2 is greater than the predetermined value Pl. At this time, the cooling fan 2 can be stopped simultaneously with the launch of the compressor 8 or driven continuously. At this time, the refrigerant pressure in the refrigerant cycle 1 is distributed between the refrigerant pressure of the high pressure side and the refrigerant pressure of the low pressure side in association with the launch of the compressor 8, and a pressure difference appears between the two refrigerant pressure values (refer to Figure 6).

  Further, after the compressor 8 has been started, timer timer t2 is started by timer 1240 (step S124), and counting is continued until timer count t2 reaches t2 'at timer step S125. If it is determined that timer count t2 reaches t2 ', compressor 8 during operation is stopped (step S126). At this time, the cooling fan 2 can be stopped or driven continuously in association with the launch of the compressor 8.

  With regard to the refrigerant pressure in the refrigerant cycle 1, in which a pressure difference occurs between that of the low pressure side and that of the high pressure side, in association with the stopping of the compressor 8, the refrigerant pressure of the the high pressure side is reduced and the pressure of the low pressure side is increased, so that the pressure difference is reduced and the two refrigerant pressure values become equal. After that, the processing proceeds to the linked processing indicated by the link mark K and progresses to the determination of the step S155 of FIG. 16 or to the determination of the step S160 of FIG. 17 of the second embodiment, in which thus going to the step of initiating the detection of the condition detection unit.

  As described above, if the refrigerant pressure in the refrigerant cycle 1 is kept below the control set pressure, damage to the equipment can be prevented in the refrigerant cycle 1. However, when the refrigerant pressure in the refrigerant cycle 1 is likely to be in the condition where it exceeds the control set pressure due to the effects of the outside air temperature, heat radiation from the engine compartment, of the heat preservation, etc., because of the operation of the engine at the time of the journey of the vehicle or the like, the treatment of the step S121 is performed again and the cooling fan 2 is launched so as to prevent the refrigerant cycle equipment 1 is damaged.

  As shown in Figures 3, 5 and 7, instead of using the pressure reducing unit to reduce the refrigerant pressure by starting the compressor 8 or the cooling fan 2 when the sensing pressure increases to the predetermined value or more, the refrigerant pressure can be reduced by a pressure reduction unit which considers that the refrigerant pressure increases and is in a high pressure state when a predetermined time has elapsed and reduces the pressure refrigerant.

  The time t1 'since the compressor is stopped 8 until the compressor 8 is started can be controlled in order to vary according to the outside air temperature. For example, when the outdoor air temperature is 30 C or more, t is set at 5 minutes. When the outside air temperature is lower than 30 C, the compressor 8 is controlled so as not to be launched.

  As described above, the vehicle refrigeration cycle device according to this embodiment is equipped with the discharge pressure sensor 9 and the controller 10. The discharge pressure sensor 9 serving as a condition detection unit detects the condition in which the refrigerant pressure is likely to exceed the control setpoint of the refrigerant cycle 1 when the vehicle engine is running or the ignition switch of the vehicle is closed and the compressor drive 8 for the refrigerant cycle is stopped. In addition, the controller 10 is set to drive at least one of the compressor 8 and the cooling fan 2 to reduce the refrigerant pressure of the low pressure side of the refrigerant cycle 1. In addition, the control set pressure is established in anticipation of the increase of the pressure in the refrigerant cycle 1 after the ignition switch has been closed.

  In accordance with the above design, the increase in refrigerant pressure due to heat from the engine, etc., at the time of vehicle travel, can be reduced, and damage to the equipment constituting the engine can be prevented. the refrigerant cycle 1 before it arrives.

  Further, in accordance with the vehicle refrigeration cycle device so designed, there is no limit to the density of the refrigerant enclosed in the refrigerant cycle, and the cycle can be protected even when the enclosed density is large. As the enclosed density may be large, the cycle capacity may be small relative to the amount of refrigerant enclosed and thus the body size of the functional portion may be reduced.

  For example, the capacity size of the battery can be designed to be small, so that it contributes to the provision of a battery with low cost and excellent mounting performance. In addition, assuming that, when it is desired that the required amount of refrigerant be set at 500 g and that it is desired that the enclosed density be set at 260 kg / m3, the capacity of the accumulator is equal at 750 cm3, even if 300 kg / m3 is allowed for the locked density of the cycle, the capacity of the accumulator is equal to 500 cm3, and thus the size of the accumulator body can be reduced.

  Further, when the control set pressure is set to be lower than the lowest resistance setpoint pressure in the refrigerant cycle 1, a vehicle refrigeration cycle device with which the protection for the function of the functional parts respective ones can be guaranteed, is realized.

  Furthermore, when the control set pressure is set to be lower than the set pressure of the booster device 7, intended to protect the equipment from the low pressure side constituting the refrigerant cycle 1, the refrigerant cycle can be protected. without performing the discharge function in the event of an increase in the refrigerant pressure at high temperature.

  Still further, the condition detection for detecting the condition that the pressure in the refrigerant cycle is likely to exceed the command set pressure is performed in the state where the ignition switch of the vehicle is closed and the engine is running. In addition, the pressure reduction unit performs the process of reducing the refrigerant pressure when the condition is detected, i.e., when the motor is driven.

  When the above command is executed, by starting the compressor during engine operation, it is possible to prevent the internal pressure from increasing when the engine is stopped. That is, after the engine is stopped, the temperature is maintained in the internal pressure of the engine compartment, and thus the ambient temperature of the refrigerant cycle is increased, so that the refrigerant pressure is also increased. .

  For example, when the refrigerant pressure is 10.5 MPa at the stopping time of the vehicle, it is increased due to the temperature of the engine compartment. When the control set pressure is 11 MPa, the discharge begins. By running the compressor during engine operation, the pressure at the vehicle stopping time is reduced to about 9 MPa. As a result, even when the interior temperature of the engine compartment is high, the degree of increase of the refrigerant cycle pressure can be cushioned. As the interior temperature of the engine compartment is gradually reduced to ambient temperature, the peak pressure of the refrigerant cycle refrigerant pressure is lower compared to the case where the compressor is not started, and therefore it is useless to launch. discharge.

  Further, when the controller 10 starts at least one of the compressor 8 for the refrigerant cycle and the cooling fan 2 at the condition detection time, the refrigerant pressure can be directly reduced by driving the compressor 8. In addition, by driving the cooling fan 2, the refrigerant temperature in the gas cooling device serving as the heat exchanger on the high pressure side is decreased and the increase in the pressure in the refrigerant cycle can be reduced. In addition, by driving both the compressor 8 and the cooling fan 2, the effect of reducing the increase of the refrigerant pressure can be further promoted.

  Still further, when the controller 10 starts at least one of the compressor 8 for the refrigerant cycle and the cooling fan 2 and also the air blower, for scuffling air to the evaporator 5, is stopped, the refrigerant pressure of the low pressure side can be reduced more quickly.

  In addition, the compressor 8 for the refrigerant cycle is constituted by a variable displacement compressor, and the pressure reduction unit is started while the controller 10 controls the capacity of the variable displacement compressor at the instant of detection of condition. In this case, by controlling the launch of the compressor, a rapid increase of the refrigerant pressure from the high pressure side to the compressor start time can be repressed.

  Further, by detecting that the refrigerant pressure in the refrigerant cycle 1 has reached a predetermined value, the control can be executed so as to be able to adapt to a rapid variation when the condition detection is performed.

  Further, when the refrigerant pressure on the discharge side of the compressor 8 is detected by the discharge pressure sensor 9, it is unnecessary to supply a condition detection unit again because an existing discharge pressure sensor equipping the refrigerant cycle can also be used as a condition detection means.

  (Second Embodiment) This embodiment is different from the first embodiment in that data for condition detection condition detection. In temperatures are used on the basis of the unit of the supercritical refrigerant cycle, when the refrigerant is enclosed with a certain enclosed cycle density, if the average cycle temperature at this time is increased, the enclosed refrigerant falls into the supercritical state, and the pressure is determined by the temperature at that moment. Accordingly, in accordance with this embodiment, the refrigerant detection is detected by detecting the refrigerant temperature.

  Then, the second embodiment will be described with reference to FIGS. 8 to 17. The same constituent elements as in the first embodiment are represented by the same reference numerals.

  Fig. 8 is a diagram showing the design of a refrigeration cycle device for a vehicle according to the second embodiment. As shown in FIG. 8, the refrigerant cycle 20 comprises a compressor 8, a discharge temperature sensor 13 serving as an example of a temperature sensing unit and a first temperature sensing unit for detecting a refrigerant temperature. on the high pressure side, a gas cooling device 2884907 3 corresponding to a heat exchanger on the high pressure side, an expansion valve 4 serving as a pressure reducing unit, an evaporator 5 corresponding to a heat exchanger, low pressure side heat, a low pressure side temperature sensor 13a for detecting the refrigerant temperature of the low pressure side of the refrigerant cycle, an accumulator 6 for separating the refrigerant into a gas phase refrigerant and a refrigerant into a refrigerant. liquid phase and supplying the gas phase refrigerant to the suction part of the compressor 8, and a pressure device 7 arranged on the low pressure side corresponding to the side of the suction part of the compressor 8, which are arranged successively and ring by means of pipes. A cooling fan 2 is provided on the gas cooling device 3 so as to oppose each other.

  The operation of an ignition switch 11, the detection value of a discharge temperature sensor 13, the detection value of a post-evaporation temperature sensor 14, the detection value of a fin temperature sensor 15, the detection value of an air-blast temperature sensor 16, the operating state of the compressor 8 and the operating state of the cooling fan 2 are inputted to a controller 17 (ECU unit) as a control unit for controlling the refrigerant cycle 20, and the operation of an air conditioner switch is also inputted.

  The controller 17 includes a timer 12, and it can count the flow of time or other at the time of operation or stop of each equipment constituting the refrigerant cycle 20. The controller 17 controls the compressor 8, the fan of cooling 2, expansion valve 4, etc., in accordance with various types of input data and preset programs.

  Fig. 9 is a diagram showing the design of a vehicle refrigeration cycle device for evaluating the refrigerant pressure on the basis of various types of monitored temperature data, obtained without directly detecting the refrigerant temperature to control the cycle. refrigerant. As shown in FIG. 9, the refrigerant 30 is equipped with the compressor 8, with the gas cooling device 3, corresponding to a heat exchanger on the high pressure side, with the expansion valve 4 serving as a pressure reduction unit. of the evaporator 5, corresponding to a heat exchanger of the low pressure side, of the accumulator 6, for separating the refrigerant into a gas phase refrigerant, and a liquid phase refrigerant and supplying the refrigerant in the gas phase at the suction port of the compressor 8, and the booster device 7, arranged at the low pressure side corresponding to the suction side of the compressor 8, which are successively ring-connected to each other via pipes. The cooling fan 2 is disposed on the gas cooling device 3 so that they are opposite to each other.

  The operation of the ignition switch 11, the detection value of a temperature sensor 18 in the engine compartment, the detection value of an outdoor air temperature sensor 19, the detection value of a solar radiation temperature sensor 21, the detection value of a cabin temperature sensor 22, the operating state of the compressor 8 and the operating condition of the cooling fan 2 are inputted to a controller 23 (ECU) serving as a control unit for controlling refrigerant cycle 30, and operation of an air conditioner switch (not shown) is also inputted to controller 23.

  The controller 23 includes a timer 12 and can count the flow of time to the operating or stopping times of each equipment constituting the refrigerant cycle 30. The controller 23 controls the compressor 8, the cooling fan 2, etc., according to various types of input data and pre-established programs.

  Next, Fig. 10 is a diagram showing the design of a vehicle refrigeration cycle device for controlling a refrigerant cycle 40 based on various types of monitored temperature data associated with the engine. As shown in FIG. 10, the refrigerant cycle 40 comprises the compressor 8, the gas cooling device 3, corresponding to a heat exchanger on the high pressure side, the expansion valve 4 acting as a pressure reduction unit. , the evaporator 5, corresponding to a heat exchanger of the low pressure side, the accumulator 6, for separating the refrigerant into a gas phase refrigerant and a liquid phase refrigerant and supplying the gas phase refrigerant to the part the suction device of the compressor 8, and the overpressure device 7, arranged on the low pressure side corresponding to the suction side of the compressor 8, which are successively connected in a ring to each other by means of pipes. The cooling fan 2 is disposed on the gas cooling device 3 so that they are opposite to each other.

  Actuation of the ignition switch (not shown), engine water temperature data, engine intake air temperature data, engine speed data, engine data the speed of the vehicle, the operating state of the compressor 8 and the operating state of the cooling fan 2 are inputted to a controller 24 (ECU) serving as a control unit for controlling the refrigerant cycle 40, and The operation of the air conditioner switch (not shown) is also inputted to the controller 24.

  In addition, the controller 24 includes a timer 12 and can count the flow of time to the operating or stopping times of the respective equipment constituting the refrigerant cycle 40. The controller 24 controls the compressor 8, the cooling fan 2, etc., according to various types of input data and pre-established programs.

  Next, the operation of the vehicle refrigeration cycle device shown in Figures 8, 9 and 10 and the variation of the refrigerant pressure during the operation concerned, describe with reference to Figures 11 and 12. Figure 11 is a flowchart showing the relationship between the change in refrigerant temperature or each type of temperature monitored and the change in refrigerant pressure in the vehicle refrigeration cycle devices shown in Figures 8, 9 and 10. Figure 12 is a timing chart showing control processing of controlling the compressor 8 based on the various types of temperature data to reduce the refrigerant pressure in the vehicle refrigeration cycle devices shown in Figures 8, 9 and 10 ( subprogramme D).

  As shown in Fig. 12, firstly, when the ignition switch (IG) is closed or the engine is running (step S100), it is determined whether the compressor 8 is stopped or not (step S111 ). When the compressor is driven, the refrigerant pressure in the refrigerant cycle. 20, 30, 40 is stable, and some difference appears between the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side. Further, it is believed that the refrigerant temperature T detected by the discharge temperature sensor 13 and the various types of temperature data monitored are equal to fixed values (see FIG. 11). When it is determined in step S111 that the compressor 8 is not stopped, the determination of the step S111 is repeated again. Then, if it is determined that the compressor 8 is stopped, after a predetermined time tl 'described later flows, the detection of the condition detection unit is started, thereby executing the reset processing. At this time, the difference that appears between the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side in the refrigerant cycle 1 is reduced with the lapse of time since the compressor was stopped 8, and the two refrigerant pressure values 1 are finally equal to each other. Then, after a prolonged flow of time, the thus equalized refrigerant pressure is increased by the effect of the outside air temperature and the effects of heat radiation from the engine compartment and heat preservation that are caused by engine operation at the time of the vehicle trip or other (see Figure 11).

  In the refrigerant cycle 20 shown in Fig. 8, it is determined whether the refrigerant temperature T based on the detection of the discharge temperature sensor 13 is equal to a predetermined value T1 or more (step S130 in Fig. 12). Likewise, when the high-pressure state of the refrigerant: is determined on the basis of the sensing values of respective types of temperature sensors, it is determined whether the sensing temperature data of the post-evaporation temperature sensor 14, the fin temperature sensor 15 and the blast temperature sensor 16 respectively are above predetermined values T2, T3, T10 respectively (step S130).

  Further, in the refrigerant cycle shown in Fig. 9, to determine the high pressure state of the refrigerant on the basis of the detected values of the various types of temperature sensors, it is likewise determined whether the temperature data in the engine compartment, the outdoor air temperature sensor 19, the solar radiation sensor 21 and the cabin temperature sensor 22 are respectively detected above the predetermined values T4, T8, T9 or T7 (step S130).

  In the refrigerant cycle 40 shown in Fig. 10, to determine the high pressure state of the refrigerant based on the detection values of the various types of temperature sensors or various types of engine data, it is likewise determined whether the respective sensing data of the engine water temperature data and the engine intake air temperature data are above a predetermined value T5 and above a predetermined value T6, or it is determined whether the respective sensing data of the engine speed data and the vehicle speed data are above predetermined values (step S130).

  When it is determined that each of the detection data, as described above, does not reach the corresponding predetermined value, the determination of step S130 is repeated again. If it is determined that each of the detection data is above the corresponding predetermined value, the processing of starting the compressor 8 is executed (step S131). At this time, the refrigerant pressure in each refrigerant cycle is divided into the high pressure side refrigerant pressure and the low side refrigerant pressure, and thus the pressure difference appears between the high side refrigerant pressure. and the low pressure side refrigerant pressure again in conjunction with the compressor start (see Figure 11).

  In addition, after the compressor 8 has been started, the count of the timer t2 is started by the timer 12 (step S132). In the step S133, the counting of the timer t2 is continued until it reaches t2 'and, if it is determined that the count of the timer t2 reaches t2', the compressor 8 during operation is stopped ( step S134).

  With regard to the refrigerant pressure in the refrigerant cycle, in which a pressure difference occurs between the high pressure side refrigerant pressure and the low pressure side refrigerant pressure, together with the compressor off 8, the refrigerant pressure on the high pressure side is reduced while the refrigerant pressure on the low pressure side is increased, and therefore the difference between them is reduced, so that the two refrigerant pressure values become equal to each other; again again and again. the refrigerant pressure is generally lower than the control set pressure. After that, the processing proceeds to the linked processing indicated by the link mark K and proceeds to the determination of step 5155 of Fig. 16 and the determination of step 5162 of Fig. 17 in the second embodiment, in which thus moving to the step of initiating the detection of the condition detection unit.

  If the refrigerant pressure in the refrigerant cycle is kept below the control set pressure, damage to the refrigerant cycle equipment can be prevented. However, when the refrigerant pressure in the refrigerant cycle 1 is likely to be in the condition in which it exceeds the control set pressure due to the effects of the outside air temperature, the heat radiation from the engine compartment, heat preservation, etc., due to the operation of the engine at the time of travel of the vehicle or the like again, the processing of step S131 is performed again and the compressor 8 is launched so as to prevent that the equipment in the refrigerant cycle 1 is damaged.

  In the course of the control process described above in FIGS. 3, 5, 7 and 12, when the counting of the timer 2 reaches the predetermined time t2 ', it is estimated that the refrigerant pressure is not high, and therefore the compressor, etc., are stopped. Conversely, the flow of the control process of stopping the compressor 8 or the like, when the refrigerant sensing pressure is reduced to a predetermined value or less, or when each type of sensing temperature is reduced to a predetermined value or less, will be described.

  Fig. 13 is a flowchart showing control processing of stopping compressor 8 or the like based on the refrigerant pressure sensing value. The detection of the coolant pressure is performed using a sensing value based on the low pressure side sensor 9a disposed on the low pressure side, for example.

  As shown in Fig. 13, firstly, in the case where the ignition switch (IG) is closed or the motor is operating (step S140), the condition detection unit further detects the condition. in which the refrigerant pressure is likely to exceed the control set pressure, and thus the treatment of starting the compressor 8 or the cooling fan 2 through the pressure reduction unit (step S141) is executed in step S142, it is determined whether the refrigerant pressure P based on the detection of the low pressure side pressure sensor 9a serving as a pressure detection unit is less than or equal to a predetermined value P10.

  When it is determined that the refrigerant pressure is not greater than a predetermined value P10, the refrigerant pressure is considered not to be high and the treatment of stopping the compressor 8 or the cooling fan 2 in operation is executed (step S143). Further, if the refrigerant pressure is determined to be greater than the predetermined value P10, the refrigerant pressure is considered to be in a high state, and thus the determination of the step S142 is repeated again.

  The next process jumps to the link mark E in the control flow chart shown in FIGS. 3, 5, 7 and 12 to execute the subprogram described above A, B, C, or D. In subprogram A, B , C or D, as a detection of the condition for stopping the compressor 8 or the like, steps S114 to S116, S118, S124 to S126 and S132 to S134 are replaced by steps S142 and S143.

  Fig. 14 is a diagram showing the flow of control processing when compressor 8 or the like is stopped based on each type of temperature sensing data. Detection of various types of temperatures is performed using temperature sensing data based on the low pressure side temperature sensor 13a, the post evaporation temperature sensor 14, the fin temperature sensor 15, the sensor. blowing air temperature 16, the engine compartment temperature sensor 18 and the cabin temperature sensor 22, for example.

  As shown in Fig. 14, firstly, when the ignition switch (IG) is closed or when the engine is running (step S140), the condition that the pressure is likely to exceed the set pressure. command is detected by the condition detection unit and thus the processing of starting compressor 8 or cooling fan 2 is performed (step S144), it is determined in step S142 whether each type of detection data temperature is not greater than a predetermined value TX. If it is determined that each type of temperature sensing data is not greater than the predetermined value TX, the refrigerant pressure is considered not to be high, and thus the treatment of stopping the compressor 8 or the cooling fan 2 in operation is executed (step S145).

  If it is determined that the temperature detection data T is. even higher than the predetermined value TX, the refrigerant pressure is considered to be in a high state and thus the determination of the step S142 is repeated again. With regard to the details of the predetermined temperature value TX for each detected temperature, the predetermined value of the refrigerant temperature is represented by TA, the predetermined value of the post-evaporation temperature is represented by TG, the predetermined value of the fin temperature is represented by TH, the predetermined value of the air blowing temperature is represented by TI, the predetermined value of the temperature of the engine compartment is represented by TB and the predetermined value of the cabin temperature ( indoor air temperature) is represented by TC.

  The subsequent processing jumps to the processing indicated by a link mark F in the control flow chart shown in FIGS. 3, 5, 7 and 12 in order to execute the subroutine described above A, B, C or D. In subroutine A, B, C or D, as a detection of the condition in which compressor 8 or the like is stopped, when the processing using each type of temperature detection data described above is executed, the processing of Steps S114 to S116, S118, S124 to S126 and 5132 to 5134 are replaced by the processing of steps 5144 and S145.

  Then, the processing (reset processing), when the detection of the condition detection unit is started, will be described with reference to Figures 15, 16 and 17. It is assumed that this processing is applicable to all control sequences of the first embodiment, this (second) embodiment and a third embodiment described later. Fig. 15 is a diagram showing the control flow representing the processing when the start time of the detection of the condition detecting unit is determined with the lapse of time. Fig. 16 is a diagram showing the control flow indicating processing when the start time of the detection of the condition detecting unit is determined based on the detection value of the refrigerant pressure. Fig. 17 is a diagram showing the progress of the command indicating processing when the start time of the detection of the condition detecting unit is determined based on each type of temperature data.

  Figure 15 shows the processing of performing the reset processing on the basis of the time flow. First, when the Ignition Ignition Switch (IG) is closed or the engine is running (Step S150), it is determined whether the compressor 8 or the cooling fan 2 is stopped or not (Step S151 ).

  In step S151, when it is determined that the compressor 8 or the cooling fan 2 is not stopped, the determination of the step S151 is repeated again. However, if it is determined that the compressor 8 or the cooling fan 2 is stopped, the timer count t1 is started by the timer 12 in step S152. The counting of the timer t1 is continued until the count of the timer t1 is greater than or equal to a predetermined value tl '. When the timer count t1 is greater than or equal to the predetermined value t1 '(step S153), the condition detection unit starts the detection (step S154).

  This processing is continued until the timer count t1 by the timer t2 is greater than or equal to the predetermined value tl ', whereby the execution of the condition detection processing is expected until the refrigerant pressure in the refrigerant cycle is estimated to be in the condition that it is equilibrated in the refrigerant cycle after the compressor 8 or the cooling fan 2 has been stopped, and the reset processing in the control flow is executed. Then, when the reset process is complete, the process skips to the subprogram described above A, B, C, D, the next routine G, H, I or J, and each routine is executed.

  Fig. 16 shows the processing flow of performing the reset processing using a refrigerant pressure detection value. First, when the ignition switch (IG) is closed or the engine is running (step S150), it is determined whether the compressor 8 or the cooling fan 2 is stopped or not (step S151) .

  If it is determined in step S151 that the compressor 8 or the cooling fan 2 is not stopped, the determination of the step S151 is repeated again. On the other hand, if it is determined that the compressor 8 or the cooling fan 2 is stopped, it is determined in step S155 whether the refrigerant pressure, based on the detection of the discharge pressure sensor 9, etc. is less than or equal to a predetermined value P3. This corresponds to the detection of the increase of the refrigerant pressure caused by the outside air temperature, the thermal radiation coming from the engine compartment due to the starting of the engine during the displacement of the vehicle, the heat preservation, etc. . This treatment is repeated until the refrigerant pressure P is less than or equal to the predetermined value P3. If the refrigerant pressure P is less than or equal to the predetermined value P3, the condition detection unit starts the detection (step S156). This treatment is continued until the refrigerant pressure P is less than or equal to the predetermined value P3, whereby, after the compressor 8 or the cooling fan 2 is stopped, the execution of the detection processing Condition is expected until the refrigerant pressure in the refrigerant cycle is estimated to be in the condition that the refrigerant pressure is stable, and the reset of the control flow is performed. When the reset processing is completed, the process jumps to the above-described routine A, B, C, D, to the next routine G, H, I, or J, and the processing of each routine is executed. .

  Fig. 17 shows the processing of performing the reset processing using the detection value of each type of temperature data. First, when the ignition switch (IG) is closed or when the engine is running (step S150), it is determined whether the compressor 8 or the cooling fan 2 is stopped (step S151).

  When it is determined in step S151 that the compressor 8 or the cooling fan 2 is not stopped, the determination of the step S151 is repeated again. On the other hand, if it is determined that compressor 8 or cooling fan 2 is stopped, it is determined in step S160 whether each type of detected temperature data T is equal to a predetermined value TY or more.

  This treatment corresponds to the detection of the increase of the refrigerant pressure caused by the outside air temperature, the heat radiation coming from the engine compartment due to the operation of the engine at the time of the journey of the vehicle, to the heat preservation etc. The predetermined value TY is set to a predetermined value TD when the refrigerant temperature is detected by the low pressure side temperature sensor 13a provided on the low pressure side of the refrigerant cycle, for example. When the refrigerant temperature is estimated and determined on the basis of the detected temperature of the post-evaporation temperature sensor 14, the fin temperature sensor 15 or the air blast temperature sensor 16, the respective predetermined values are stalls at TJ, TK, TL. Further, when the refrigerant pressure state is determined using the sensing value of the engine compartment temperature sensor 18, the predetermined value is set to TE, and when the refrigerant pressure state is determined using the detection value of the cabin temperature sensor 22, the predetermined value is set to TF.

  This process is repeated until each detected temperature data type T is equal to a predetermined value TY or more, and if it is greater than or equal to the predetermined value TY, the condition detection unit starts the detection (step S161). This processing is continued until each type of detection temperature data T is greater than or equal to the predetermined value TY, whereby after the compressor 8 or the cooling fan 2 is stopped, the execution of Condition detection processing is expected until the refrigerant pressure in the refrigerant cycle is estimated to be in the condition where it is equalized, and the reset of the control flow is performed. When this reset processing is complete, the process jumps to the above described subprogram A, B, C, D, to the next routine G, H, I or J, and each routine is executed.

  As described above, in the vehicle refrigerant cycle of this embodiment, the condition detection unit is constituted by the discharge temperature sensor 13 (first temperature detection unit), for detecting that the refrigerant temperature in the refrigerant cycle 20, 30, 40 reaches the predetermined value. In the case of this design, the refrigerant pressure in the refrigerant cycle can be determined reliably by performing the condition detection based on the refrigerant temperature. Furthermore, it is unnecessary to provide a first temperature sensing unit again, because the existing discharge temperature sensor provided on the refrigerant cycle is used as the first temperature sensing unit.

  In addition, the vehicle refrigeration cycle device of this embodiment is equipped with the low pressure side pressure sensor 9a for detecting the condition in which the refrigerant pressure is likely to exceed the control set pressure of the cycle. refrigerant 20, 30, 40 when the vehicle engine is running or when the ignition switch ignition 8 of the vehicle is closed and also when the compressor 8 for the refrigerant cycle is in the stopped state. In addition, the controller 17, 23, 24 is provided to launch at least one of the compressor 8 and the cooling fan 2 so as to reduce the refrigerant pressure of the low pressure side of the refrigerant cycle 20, 30, 40 to the moment of condition detection. In addition, the control set pressure is set in anticipation of the increase of the pressure in the refrigerant cycle 20, 30, 40 after the ignition switch is turned on. open. According to this design, the increase of the refrigerant pressure which is caused by heat from the engine, etc., during the vehicle travel time can be repressed, and damage to the equipment constituting the engine can be prevented. refrigerant cycle 20, 30, 40 before it arrives.

  Further, when the control set pressure is set to be lower than the lowest resistance setpoint pressure of the refrigerant cycles 20, 30, 40, a vehicle refrigeration cycle device that can guarantee the functions of the parts respective functionalities can be realized.

  Still further, when the control set pressure is set to be lower than the set pressure of the booster device 7 to protect the equipment constituting the refrigerant cycle 20, 30, 40, the refrigerant cycle can be protected without performing the discharge function during the increase of the refrigerant pressure at high temperature.

  Still further, when the first temperature sensing unit is constituted by the post-evaporation temperature sensor 14, the fin temperature sensor 15 or the air blowing temperature sensor 16, the temperature state The high temperature of the refrigerant can be estimated by detecting each type of temperature data, and thus the refrigerant pressure state in the refrigerant cycle can be determined.

  Still further, when the condition detecting unit is comprised of the second temperature detecting unit for detecting whether any of the temperature in the engine compartment and the temperature in the passenger compartment reaches a predetermined value, the refrigerant pressure state in the refrigerant cycle can be determined by performing the condition detection based on each type of temperature data.

  When the temperature in the passenger compartment is detected on the basis of any one of the cabin temperature sensor 22, intended to directly detect the cabin temperature, of the outside air temperature sensor 19, intended to indirectly detect the temperature of the passenger compartment, and the solar radiation temperature sensor 21, it is unnecessary to provide a detection unit again because each existing type of sensor is used as a detection unit for the temperature of the cabin.

  Still further, when the second temperature sensing unit is designed so that it is determined, based on the sensing value of any of the engine water temperature and the intake temperature. of the engine, if the temperature in the engine reaches a predetermined value, the temperature in the engine compartment is determined by actively using each of the existing engine data detected normally, whereby it is unnecessary to provide a temperature sensing unit again .

  Still further, when the condition detecting unit is constituted by a stopping detecting unit 12 (timer) for detecting whether the stopping time of the compressor 8 reaches a predetermined time, the condition detection is performed, counting the downtime of the compressor 8, whereby the existing timer function on the compressor 8 can also be used as the condition detecting unit, and thus there is no need to supply a unit again. condition detection.

  Still further, after at least one of the compressor 8 and the cooling fan 2 is started by the controller 17, 23, 24, the controller 17, 23, 24 stops at least one of the compressor 8 and the fan in operation when a predetermined time has elapsed. When this command is adopted, the existing timer function provided for the refrigeration cycle device may also be used as the stopping condition detection unit, and therefore there is no need to provide a condition detection unit again. stop.

  When the controller 17, 23, 24 determines that the refrigerant pressure in the refrigerant cycle 20, 30, 40 is greater than or equal to a predetermined value after at least one of the compressor 8 and the cooling fan 2 is initiated by the controller at the condition detection time, at least one of the compressor 8 and the cooling fan 2 in operation is stopped. When this command is adopted, the refrigerant pressure is detected and used for the stopping condition detection, whereby the control can be executed so that the variation of the refrigerant pressure can be followed rapidly.

  When, at the time of the condition detection, the controller 17, 23, 24 determines that the refrigerant temperature of the low pressure side in the refrigerant cycle 20, 30, 40 is less than or equal to a predetermined value or determines that the any of the post-evaporation temperature, the fin temperature and the air blowing temperature is less than or equal to a predetermined value, at least one of the compressor 8 and the cooling fan 2 is started by the controller 17, 23, 24, the controller 17, 23, 24 stops at least one of the compressor 8 and the cooling fan 2 in operation.

  When this command is adopted, the stopping condition detection is performed based on the refrigerant temperature, the refrigerant pressure in the refrigerant cycle can be determined correctly. Further, when the stopping condition detection is performed on the basis of the post-evaporation temperature, the fin temperature, or the air blowing temperature, the refrigerant pressure can be estimated and determined by detecting the refrigerant temperature level of the evaporator.

  In addition, at the condition detection time, the controller 17, 23, 24 determines that any of the engine compartment temperature and the cabin temperature is less than or equal to a predetermined value after at least one of the compressor 8 and the cooling fan 2 is started by the controller, the controller stops at least one of the compressor 8 and the cooling fan 2 in operation. When this command is adopted, the refrigerant pressure state in the refrigerant cycle can be determined by performing the stop condition detection using each type of temperature data.

  When a predetermined time elapses after at least one of the compressor 8 and the cooling fan 2 is stopped, the condition detection unit starts the detection. In this case, the existing timer function provided for the refrigerant cycle is also used to detect the reset processing time, whereby it is unnecessary to provide a detection unit again.

  In addition, when it is determined that the refrigerant pressure of the high pressure side in the refrigerant cycle 20, 30, 40 is less than or equal to a predetermined value after at least one of the compressor 8 and the cooling fan cooling 2 is stopped, the condition detection unit starts the detection. In this case, the reset processing time is detected by detecting the refrigerant pressure, whereby the reset processing can be performed so that the change in refrigerant pressure can be monitored quickly.

  Further, when it is determined that the refrigerant temperature of the low pressure side in the refrigerant cycle 20, 30, 40 reaches a predetermined value after at least one of the compressor 8 and the cooling fan 2 is stopped or when it is determined that any of the post-evaporation temperature, the fin temperature, and the air blowing temperature reaches a predetermined value, the condition detecting unit initiates the detection. In this case, when the reset processing time is detected on the basis of the refrigerant temperature, the refrigerant pressure in the refrigerant cycle can be correctly determined and the reset processing can be performed. Further, when the reset processing time is detected on the basis of the post-evaporation temperature, the fin temperature, or the air blowing temperature, the refrigerant pressure can be estimated and determined by detecting the refrigerant temperature level in the evaporator.

  In addition, after at least one of the compressor 8 and the cooling fan 2 is stopped, when it is determined that any of the engine compartment temperature and the cabin temperature reaches a value of predetermined, the condition detection unit initiates the detection. In this case, the reset processing time is detected using each type of temperature data, whereby the reset processing based on the estimation of the refrigerant pressure state in the refrigerant cycle can be performed. .

  (Third Embodiment) In the third embodiment, in the state where the ignition switch (IG) is open, the compressor or cooling fan is started at the condition detection time, and then the stop command is executed as in the case of FIGS. 3, 5 and 12. The different point of the third embodiment with respect to the first and second embodiments is that an electrically driven compressor and a fan electrically driven coolers are controlled in place of the compressor 8 and the cooling fan 2 to maintain the refrigerant pressure at a proper level. The third embodiment will be described below with reference to Figures 18 to 21.

  Fig. 18 is a control flow chart showing the process of reducing the pressure of a refrigerant by controlling the electrically driven compressor based on the detection value of the refrigerant pressure when the ignition switch (IG ) is open.

  In this control sequence shown in Fig. 18, firstly, when the ignition switch (IG) is open (step S170), it is determined whether the electrically driven compressor is stopped (step S171). When the electrically driven compressor is not stopped, with respect to the refrigerant pressure in the refrigerant cycle, there is a difference between the refrigerant pressure at the high pressure side and the refrigerant pressure at the low pressure side. If it is determined in step S171 that the electrically driven compressor is not stopped, the determination of step S171 is repeated again. However, if it is determined that the electrically driven compressor is stopped, the reset processing described above is executed, and the condition detection unit starts the detection.

  Then, it is determined in step S172 whether the refrigerant pressure P based on the detection of the discharge pressure sensor 9 is greater than or equal to a predetermined value P '. When the electrically driven compressor is stopped, the refrigerant pressure P is increased through the effect of the outside air temperature, the effect of the heat radiation from the engine compartment and the heat preservation due to it. the operation of the engine at the time of the journey of the vehicle or other, etc. When it is determined that this refrigerant pressure reaches the predetermined value P ', the processing of starting the electrically driven compressor is performed (step S173).

  Further, when it is determined that the refrigerant pressure does not reach the predetermined value P ', the determination of the step S172 is again repeated. At this time, the refrigerant pressure in the refrigerant cycle is distributed between the refrigerant pressure on the high pressure side and the refrigerant pressure on the low pressure side again and a pressure difference appears between them. In addition, after the electrically driven compressor is started, the count of timer t2 is started by timer 12 (step S174). In step S175, the counting is continued until the count of timer t2 reaches t2 ', and if it is determined that the count of timer t2 reaches t2', the electrically driven compressor during operation is stopped. (Step S176).

  In the refrigerant cycle in which a pressure difference occurs between the high pressure side and the low pressure side, the refrigerant pressure at the high pressure side is reduced and the refrigerant pressure at the low pressure side is increased due to the shutdown electrically driven compressor in step S176, so that the pressure difference between them is reduced. As a result, the two refrigerant pressure values at the high and low pressure sides are made equal, and the entire refrigerant pressure is controlled to be lower than the control set pressure overall. After that, the processing proceeds to the processing indicated by the link mark K, and thus proceeds to the determination of step S155 of Fig. 16 and the determination of step S160 of Fig. 17, indicated in the second mode. wherein the processing proceeds to the step of initiating the detection of the condition detecting unit.

  If the refrigerant pressure in the refrigerant cycle is maintained to be lower than the control set pressure as described above, the equipment of the refrigerant cycle can be prevented from being damaged.

  However, in the case of the condition where the refrigerant pressure in the refrigerant cycle 1 is likely to exceed the control set pressure due to the effect of the outside air temperature, the effect of the radiation of heat from the engine compartment, and heat storage, etc., which are caused by the operation of the engine at the time of the vehicle or the like, the processing of step S173 is performed again to prevent damage. of the equipment in the refrigerant cycle, by launching the electrically driven compressor accordingly.

  Next, Fig. 19 is a control flow chart showing the process of controlling the electrically driven cooling fan based on the detection value of the refrigerant pressure to reduce the refrigerant pressure when the contact switch of Ignition (IG) is open.

  In this control sequence shown in Fig. 19, firstly, when the ignition switch (IG) is open (step S170), it is determined whether the compressor is stopped (step S177). If the compressor is not stopped, with respect to the refrigerant pressure in the refrigerant cycle, a pressure difference occurs between the refrigerant pressure of the high pressure side and the refrigerant pressure of the low pressure side. If it is determined in step S177 that the compressor is not stopped, the determination of step 5177 is repeated again. However, if it is determined that the compressor is stopped, the reset processing described above is executed, and the condition detection unit initiates the detection.

  Then, it is determined in step S178 whether the refrigerant pressure P, based on the detection of the discharge pressure sensor 9, is greater than or equal to a predetermined value P '. When the compressor is stopped, the refrigerant pressure P is increased due to the effect of the outside air temperature, the effect of the heat radiation of the engine compartment and the heat preservation, etc., of the makes the operation of the engine at the time of the vehicle trip or the like, and if it is determined that this refrigerant pressure reaches the predetermined value P ', the processing of starting the electrically driven cooling fan is performed (step S179).

  If it is determined that the refrigerant pressure P does not reach the predetermined value P ', the determination of the step S178 is repeated again. At this time, the refrigerant pressure P in the refrigerant cycle is controlled to be lower than the predetermined value P 'because the refrigerant is cooled by the launch of the electrically driven cooling fan. Further, after the electrically driven cooling fan is started, counting of timer t2 is started by timer 12 (step S180). In step 5181, counting of timer t2 is continued until the count of timer t2 reaches t2 '. If it is determined that the count of timer t2 reaches t2 ', the electrically driven cooling fan in operation is stopped (step S182).

  The refrigerant pressure in the refrigerant cycle, which is reduced to be less than the predetermined value P ', is progressively increased due to the effect of the outside air temperature, the effect of the heat radiation from . engine compartment and heat storage, etc., due to the operation of the engine during the journey of the vehicle or other. After that, the processing proceeds to the processing indicated by the link mark K, and thus proceeds to the determination of step 5155 of Fig. 16, and the determination of step S160 of Fig. 17, whereby the processing proceeds to the step of initiating the detection of the condition detection unit.

  If the refrigerant pressure in a refrigerant cycle is maintained to be lower than the control set pressure as described above, the equipment in the refrigerant cycle can be prevented from being damaged.

  However, in the case of the condition where the refrigerant pressure in the refrigerant cycle is likely to exceed the control set pressure due to the effect of the outside air temperature, the effect of the radiation of heat from the engine compartment and heat storage, etc., which are caused by the operation of the engine during the vehicle travel time or the like, the processing of step S179 is performed again to prevent damage to the engine. refrigerant cycle equipment, thus launching the electrically driven cooling fan.

  Next, Fig. 20 is a control flow chart showing the process of controlling the electrically driven cooling fan based on each type of temperature data T to reduce the refrigerant pressure when the ignition switch ( IG) is open. In this control sequence, firstly, when the ignition switch (IG) is open (step S170), it is determined whether the compressor is stopped (step S177). Further, it is considered that the refrigerant temperature detected by the discharge temperature sensor 13 or the like and each type of temperature data being monitored are fixed values.

  If it is determined in step S177 that the compressor is not stopped, the determination of step S177 is repeated again. When the compressor is stopped, the refrigerant pressure is increased due to the effect of the outside air temperature, the effect of heat radiation from the engine compartment engine, heat storage, etc. , because of the operation of the engine at the time of the journey of the vehicle or other.

  When it is determined whether the compressor is stopped in the refrigerant cycle 20 shown in Fig. 8, it is determined whether the refrigerant temperature T, based on the detection of the discharge temperature sensor 13, is greater than or equal to at a predetermined value T '(step S183). In the same way, when the high-pressure state of the refrigerant is determined on the basis of the detection value of each type of temperature sensor, it is determined whether each of the detection temperature data T of the temperature sensor of post evaporation 14, the fin temperature sensor 15 or the air blast temperature sensor 16 is not less than a predetermined value T2, T3, or T10 (step S183).

  In the refrigerant cycle 30 shown in FIG. 9, in the same way, to determine the high pressure state of the refrigerant on the basis of the detection value of each type of temperature sensor, it is determined whether the detected temperatures T of each sensor among the compartment temperature sensor 18, the outdoor air temperature sensor, the solar radiation temperature sensor 21 and the cabin temperature sensor 22 are not less than a predetermined value T4 , T8, T9 or T7 (step S183).

  Alternatively, in the refrigerant cycle 40 shown in FIG. 10, in the same way, when the high-pressure state of the refrigerant is determined on the basis of the detection value of each type of temperature sensor, or each type of engine data, it is determined whether the detection data (T) of each of the engine water temperature data and the engine intake air temperature data are not less than a predetermined value T5, T6, or if the detection data of each of the engine speed data and the vehicle speed data is not less than a predetermined value (step S183).

  If it is determined that each of the detection data (T), as described above, does not reach the predetermined value (T '), the determination of the step S183 is repeated. However, if each of the detection data (T) is greater than or equal to a predetermined value (T '), the processing of starting the electrically driven cooling fan is performed (step S184). At this time, the refrigerant pressure in each refrigerant cycle acts to reduce the electrically driven cooling fan in conjunction with the launch of the electrically driven cooling fan.

  In addition, after the electrically driven cooling fan is started, timer count t2 is started by timer 12 (step S186). In step 5186, counting of timer t2 is continued until timer count t2 reaches t2 ', and if it is determined that timer count t2 reaches t2', refrigerant pressure is considered as not being high, and thus the electrically driven cooling fan in operation is stopped (step S187).

  After that, the processing proceeds to the processing indicated by the link mark K and thus proceeds to the determination of step S155 of Fig. 16 or the determination of step 5160 of Fig. 17 in the second embodiment, whereby the greed treatment up to the step of initiating the detection of the condition detection unit. In addition, the electrically driven fan can be controlled to be driven continuously when the refrigerant pressure is even higher than the control set pressure overall.

  If the refrigerant pressure in the refrigerant cycle is maintained to be lower than the control set pressure as described above, the equipment in the refrigerant cycle can be prevented from being damaged.

  However, in the case of the condition where the refrigerant pressure in the refrigerant cycle 1 is likely to exceed the control set pressure due to the effect of the outside air temperature, the effect of the radiation of engine compartment heat and heat preservation, etc., which are caused by the operation of the engine at the time of vehicle travel or the like, the processing of step S185 is performed again to prevent damage to the engine. refrigerant cycle equipment, thus launching the electrically driven cooling fan. The control flow shown in Fig. 20 shows the flow of controlling the electrically driven cooling fan, however the same effect can be obtained if it is replaced by the treatment of controlling the electrically driven compressor.

  Fig. 21 is a control flow chart showing the processing of detecting the compressor off time by timer 12 when the ignition switch (IG) is open, considering the refrigerant as being in a state of high pressure when the detection time is equal to a predetermined time or more, and controlling the electrically driven cooling fan to reduce the refrigerant pressure.

  In this control sequence, firstly, when the ignition switch (IG) is open (step S170), it is determined whether the compressor is stopped or not (step S177). If it is determined in step S177 that the compressor is not stopped, the timer count t1 is started by the timer 12 to detect the compressor off time in step S190.

  The counting is continued until the count of the timer t1 is greater than or equal to t1 '(step S191), and if it is determined that the count of the timer t1 is greater than or equal to tl', the refrigerant pressure is in the high pressure state, and thus the electrically driven cooling fan is started (step S192). At this time, the refrigerant pressure in the refrigerant cycle is controlled to be lower than the control set pressure because the refrigerant is cooled by launching the electrically driven cooling fan, for example.

  Further, after the electrically driven cooling fan is started, counting of timer t2 is started by timer 12 (step S193). In step S194, counting of timer t2 is continued until it reaches t2 ', and if it is determined that the count of timer t2 reaches t2', the electrically driven cooling fan in operation is stopped. (Step S195).

  When the refrigerant pressure in the refrigerant cycle is lower than the control set pressure, the refrigerant pressure is gradually increased due to the effect of the outside air temperature, the radiation effect of heat from the engine compartment and heat preservation due to engine operation during vehicle travel time or other, etc. due to engine shutdown. After that, the processing proceeds to the processing indicated by the link mark K, and thus proceeds to the determination of step S155 of Fig. 16 or the determination of step S160 of Fig. 17 in the second embodiment. , whereby the processing progresses to the step of initiating the detection of the condition detecting unit.

  If the refrigerant pressure in the refrigerant cycle is kept below the control set pressure as described above, the equipment of the refrigerant cycle can be prevented from being damaged.

  However, in the case of the condition in which the refrigerant pressure in the refrigerant cycle is likely to exceed the set pressure due to the effect of the outside air temperature, the effect of heat radiation from of the engine compartment and the heat storage, etc., which are caused due to the operation of the engine at the time of the vehicle journey or the like, the processing of step S192 is performed again to prevent damage to the engine. refrigerant cycle equipment, by launching the electrically driven cooling fan accordingly. The control flow shown in Fig. 21 shows the flow of controlling the electrically driven cooling fan, however, the same effect can be obtained if it is replaced by the treatment of controlling the electrically driven compressor. electrically driven compressor and electrically driven cooling fan, they are started when the residual amount of the battery voltage is greater than or equal to a predetermined voltage. The drive of the electrically driven compressor and the electrically driven cooling fan can be controlled while also providing the refrigerant pressure state in the refrigerant cycle by monitoring the various types of temperature data of the discharge pressure sensor 9 , the discharge temperature sensor 13, etc. In addition, the time tl from the compressor stop to the launch of the compressor can be controlled so as to be varied according to the outside air temperature. For example, when the outside air temperature is not less than 30 C, tl 'is set at 5 minutes, and when the outside air temperature is below 30 C, the compressor is not started .

  As described above, the vehicle refrigeration cycle device according to this embodiment is equipped with the condition detection unit for detecting the condition in which the refrigerant pressure is likely to exceed the set pressure of controlling the refrigerant cycle when the ignition switch for the vehicle is in the open state, and the pressure reducing unit for reducing the refrigerant pressure of the low pressure side when the condition is detected. The pressure reduction unit starts at least one of the electrically driven compressor and the electrically driven cooling fan through the control unit when the condition is detected.

  According to this design, in the state where the ignition switch is open, the launch is executed using power even after the ignition switch is open, and thus this design can be suitable for increasing the refrigerant pressure. In addition, the refrigerant pressure at the start time can be set to be close to the control set pressure, and thus the loss of the driving force can be reduced.

  In addition, the condition detection unit is constituted by the discharge pressure sensor 9 for detecting whether the refrigerant pressure in the refrigerant cycle reaches a predetermined value. In the case of this design, the refrigerant pressure is detected and used for the condition detection, whereby the control can be executed while rapidly following the variation of the refrigerant pressure.

  In addition, the condition detection unit is constituted by the discharge temperature sensor 13 as a temperature detection unit for detecting whether the refrigerant temperature in the refrigerant cycle reaches a predetermined value. In the case of this constitution, the refrigerant pressure in the supercritical refrigerant cycle can surely be determined by performing the condition detection on the basis of the refrigerant temperature.

  In addition, the condition detection unit is constituted by the engine compartment temperature sensor 18 or the cabin temperature sensor 22 as a second temperature detection unit for detecting whether any of the engine compartment temperature and cabin temperature reaches the predetermined value. In this case of this design, the refrigerant pressure state in the supercritical refrigerant cycle can be determined by performing the condition detection with the various types of temperature data.

  Still further, the condition detecting unit is constituted by the timer 12 for detecting whether the stopping time of the compressor 8 in the refrigerant cycle reaches a predetermined time. In the case of this design, the condition detection is performed by counting compressor downtime, whereby the existing timer function provided for the compressor can also be used as a condition detection unit, and therefore, it is unnecessary to provide a condition detection unit again.

  (Other Embodiments) The present invention is not limited to the embodiments described above, and various types of modifications may be made as follows without departing from the object of the present invention.

  For example, the refrigeration cycle devices of the embodiments described above may be constituted by a refrigerant cycle having an internal heat exchanger. The internal heat exchanger is a heat exchange heat exchanger exchanging heat, circulating between a heat exchanger in the passenger compartment and a heat exchanger outside the vehicle, with a refrigerant leaving the accumulator and sucked in the compressor.

  The refrigeration cycle devices of the embodiments described above may be constituted by an ejector cycle using an ejector. The ejector includes a nozzle portion for converting the pressure energy of an incoming flow refrigerant into the kinetic energy of the refrigerant so that the refrigerant pressure is reduced and the refrigerant is relieved, a mixing portion for mixing the high-speed refrigerant stream ejected from the nozzle portion with a gas-phase refrigerant which is evaporated in the evaporator by the high-speed refrigerant stream ejected from the nozzle portion while sucking the refrigerant in phase and a diffuser portion for converting the kinetic energy into pressure energy while mixing the refrigerant ejected from the nozzle with the refrigerant sucked from the evaporator, thereby increasing the refrigerant pressure.

  Furthermore, in all the embodiments described above, the control set pressure can be set in anticipation of the increase of the refrigerant cycle pressure 1 after the ignition switch is open. In addition, the control set pressure can be set in anticipation of the refrigerant cycle pressure increase 1 caused by the residual heat of the engine after the ignition switch is open.

  This is because the exhaust heat of the engine, after the ignition switch is open, remains in the engine compartment, and thus the ambient temperature of the refrigerant cycle is increased, so that the internal pressure refrigerant cycle is increased. In other words, the control set pressure can be set in anticipation of the amount corresponding to the temperature increase, i.e. the pressure increase of the internal pressure of the refrigerant cycle. .

  The control set pressure is varied according to the external environment, for example the temperature of the outside air, the heat of the earth, the temperature of the solar radiation, the arrangement of the motor, the the displacement of the engine or the arrangement of the air conditioning cycle, as it is affected by the temperature in the engine compartment. For example, the control set pressure differs between the case where the outside air temperature is 35 C and the case where the outside air temperature is 45 C, because the degree of Increasing refrigerant pressure is different between the two cases.

  The control set pressure can be determined after the pressure increase, corresponding to the variation of the environment for each vehicle as described above, has been reached or after a situation that appears to be the worst has been taken, in other words, the maximum pressure increase is reached. For example, when the outside air temperature is equal to 35 C, the control set pressure is set to 10 MPa, and when the outside air temperature is equal to 45 C, the control set pressure is set at 9 MPa.

  Furthermore, with respect to the vehicle refrigeration cycle devices of all embodiments, the internal pressure condition of the refrigerant cycle, wherein the refrigerant pressure is likely to exceed the cycle control set pressure. refrigerant, is detected by the condition detection unit, the compressor and / or the cooling fan is started by the controller, and when the compressor and / or the cooling fan is stopped after that, neither a flow of predetermined time, nor a limitation of the refrigerant pressure is required. As a result, the detection of the condition detection unit can be started again based on the shutdown of the compressor or cooling fan.

  Still further, the condition detection unit of each of the embodiments may be designed to detect the condition that the refrigerant pressure is likely to exceed the control set pressure of the refrigerant cycle 1 in the state where the vehicle engine is not running or the vehicle ignition switch is open. In this case, the condition detection unit can be adapted to increase the refrigerant pressure without using the motor through the electric power, for example a battery or the like.

  Still further, in the third embodiment, the internal pressure condition of the refrigerant cycle in which the refrigerant pressure is likely to exceed the control set pressure during engine operation, can be executed in the state wherein the vehicle ignition switch is closed, and further, when this condition is detected, i.e., during the operation of the engine, the electrically driven compressor or the electrically driven cooling fan may be launched to reduce the pressure. In this case, the consumption of the battery voltage can be prevented.

  Still further, the electrically driven compressor and the electrically driven cooling fan of the third embodiment have the same operation and effect as the first and second embodiments by applying to the compressor 8 and the cooling fan 2 of the first and second embodiments. second embodiments.

  In the embodiments described above, the vehicle refrigeration cycle device uses the containing refrigerant. carbon dioxide as the main component. However, another refrigerant generally used for a refrigerant cycle can be used. For example, another refrigerant used in a supercritical state can be used as a refrigerant.

  Although the invention has been described with reference to its preferred embodiments, it should be understood that the invention is not limited to the preferred embodiments and designs. It is intended that the invention covers various modifications and equivalent arrangements. Furthermore, although the various elements of the preferred embodiments are presented in various combinations and configurations, which are preferred, other combinations and configurations comprising more elements, fewer elements or only a single element, are also found. in the spirit and scope of the invention.

Claims (33)

  Refrigeration cycle device for a vehicle comprising.   a refrigerant cycle (1, 20, 30, 40) through which a refrigerant circulates, a condition detection unit (9, 9a, 12, 13, 13a, 14 to 16, 18, 19, 21, 22) for detecting a condition in which an internal pressure of the refrigerant cycle exceeds a control set pressure, and a pressure reducing means for reducing a refrigerant pressure of a low pressure side of the refrigerant cycle when the condition is detected .   2. A cycle device claim 1, wherein the is set to a higher refrigeration value according to the low control set pressure than a set value which is set for a pressure in the refrigerant cycle.   lowest resistance The cycle apparatus of claim 1, wherein: the refrigerant refrigerant cycle according to claim 1 comprises a pressure relief device (7) having a set pressure for protecting equipment on the low pressure side in the refrigerant cycle, and the pressure control set point is set to be lower than the set pressure of the booster device.   4. A refrigeration cycle device according to claim 3, wherein the control set pressure is set to be lower than the set pressure of the pressure relief device to protect the equipment from the low pressure side of the refrigerant cycle of 0. , 5 MPa or more.   The refrigeration cycle device according to any of claims 1 to 4, wherein the control set pressure is set in a range between 7 MPa and 12 MPa.   The refrigeration cycle device according to any one of claims 1 to 5, wherein the control set pressure is set in anticipation of an increase in the pressure in the refrigerant cycle.   The refrigeration cycle device according to claim 6, wherein the control set pressure is set in anticipation of an increase in the pressure in the refrigerant cycle due to the residual heat of a vehicle engine after a vehicle ignition switch has been opened.   The refrigeration cycle device according to claim 6, wherein the refrigerant cycle comprises a pressure device (7) having a set pressure for protecting equipment on the low pressure side in the refrigerant cycle, and the pressure The control set point is set to be lower than the set pressure of the pressure relief device by 1.0 MPa or more.   The refrigeration cycle device according to any one of claims 1 to 8, wherein the refrigerant cycle comprises a compressor (8) for compressing a refrigerant, a gas cooling device (3) for cooling the refrigerant. discharged from the compressor, and a cooling fan (2) for blowing air to the gas cooling device, the apparatus further comprising a control unit (10, 17, 23, 24) which controls the operation of the refrigerant cycle, wherein the pressure reducing means initiates at least one of the cooling fan and the compressor through the control unit when the condition detection unit detects the condition, and reduces the pressure of the refrigerant on the low pressure side in the refrigerant cycle.   The refrigeration cycle device according to any one of claims 1 to 8, wherein the refrigerant cycle comprises a variable displacement compressor (8) for compressing the refrigerant in the refrigerant cycle, the device further comprising a control unit (10, 17, 23, 24) which controls the operation of the refrigerant cycle, wherein the pressure reducing means starts the variable displacement compressor while a discharge capacity of the variable displacement compressor is controlled by the control unit when the condition detection unit detects the condition.   The refrigeration cycle device according to any one of claims 1 to 8, wherein the refrigerant cycle comprises a compressor (8) for compressing a refrigerant, the compressor being driven using a vehicle engine as a source. the device further comprising a control unit (10, 17, 23, 24) which controls the operation of the refrigerant cycle, wherein the pressure reducing means starts the compressor through the control unit. control to reduce the refrigerant pressure of the low pressure side when the condition detection unit detects the condition.   The refrigeration cycle apparatus according to claim 11, wherein the condition detection unit detects the condition while a vehicle engine is operated in a state where a vehicle ignition switch is closed. .   Refrigeration cycle apparatus according to claim 9, wherein the compressor consists of an electrically driven electric compressor.   The refrigeration cycle apparatus of claim 13, wherein the condition detecting unit detects the condition in a state where a vehicle ignition switch has been opened.   The refrigeration cycle device according to claim 1, wherein the refrigerant cycle comprises a compressor (8) for compressing the refrigerant, a gas cooling device (3) for cooling the refrigerant discharged from the compressor, an evaporator. (5) for evaporating the refrigerant after it has been decompressed, a first fan (2) for blowing air to the gas cooling device, and a second fan for blowing air towards the gas cooling device; the evaporator, the apparatus further comprising a control unit (10, 17, 23, 24) which controls the operation of the refrigerant cycle, or when the condition detection unit detects the condition, at least one of the first fan and compressor is driven and the second fan is stopped by the control unit.   The refrigeration cycle device according to any one of claims 1 to 15, wherein the condition detection unit comprises a pressure sensing unit (9, 9a) for detecting whether the refrigerant pressure in the cycle refrigerant reaches a predetermined value.   The refrigeration cycle apparatus according to claim 16, wherein the pressure sensing unit comprises a discharge pressure sensor (9) for detecting the refrigerant pressure on the discharge side of the compressor in the refrigerant cycle.   The refrigeration cycle device according to any one of claims 1 to 15, wherein the condition detection unit comprises a first temperature detection unit (13, 14, 15, 16) for detecting whether a temperature refrigerant in the refrigerant cycle reaches a predetermined value.   Refrigeration cycle apparatus according to claim 18, wherein the first temperature sensing unit comprises a discharge temperature sensor (13) for detecting a refrigerant temperature on a discharge side of a cycle compressor. refrigerant.   The refrigeration cycle apparatus according to claim 18, wherein the first temperature sensing unit comprises at least one of a post-evaporation temperature sensor (14) for sensing an air temperature which through an evaporator (5) of the refrigerant cycle, a fin temperature sensor (15) for detecting a temperature of a fin of the evaporator, and an air blowing temperature sensor. (16) for detecting a temperature of air to be blown into the passenger compartment of the vehicle.   The refrigerant cycle device according to any one of claims 1 to 15, wherein the condition detection unit comprises a second temperature detection unit (18, 19, 21, 22) for detecting whether the any of a temperature in a vehicle engine compartment and a temperature in the passenger compartment of the vehicle reaches a predetermined value.   The refrigeration cycle apparatus according to claim 21, wherein the second temperature sensing unit determines the temperature of the passenger compartment based on at least one of the sensing values of a temperature sensor. indoor air (22) for directly detecting the air temperature in the passenger compartment, an outside air temperature sensor (19) for indirectly detecting the temperature in the passenger compartment, and a sensor solar radiation temperature (21) for detecting a quantity of solar radiation entering the passenger compartment.   The refrigeration cycle apparatus of claim 21, wherein the second temperature sensing unit determines, based on the sensing value of any of a motor water temperature and a temperature. engine intake air, if the temperature in the engine compartment reaches the predetermined value.   The refrigeration cycle apparatus of any one of claims 1 to 23, wherein the condition detecting unit includes a dwell time detecting unit (12) for detecting whether a dwell time of a compressor of the refrigerant cycle reaches a predetermined time.   25. A refrigeration cycle device according to any one of claims 16 to 24, further comprising a control unit (10, 17, 23, 24) for controlling the operation of the refrigerant cycle, wherein the refrigeration unit command initiates at least one of a cooling fan (2) for blowing air to a gas cooling device (3), and a compressor (8) of the refrigerant cycle when the cooling unit condition detection detects the condition, and then the control unit stops at least one of the compressor and the cooling fan during operation when a predetermined time has elapsed.   The refrigeration cycle apparatus according to any of claims 16 to 24, further comprising a control unit (10, 17, 23, 24) for controlling the operation of the refrigerant cycle, wherein the refrigeration unit control initiates at least one of a cooling fan (2) for blowing air to a gas cooling device (3) and a compressor (8) of the refrigerant cycle when the cooling unit condition detection detects the condition, and then the control unit shuts down at least one of the compressor and the cooling fan during operation when the control unit determines that the refrigerant pressure in the refrigerant cycle is lower or equal to a predetermined value.   Refrigeration cycle apparatus according to any of claims 16 to 24, further comprising a control unit (10, 17, 23, 24) for controlling the operation of the refrigerant cycle, wherein the refrigeration unit control initiates at least one of a cooling fan (2) for blowing air to a gas cooling device (3) and a compressor (8) of the refrigerant cycle when the cooling unit condition detection detects the condition, and then the control unit stops at least one of the compressor and the cooling fan in operation when the control unit determines that the refrigerant temperature in the refrigerant cycle is less than or equal to at a predetermined value, or any of a post-evaporation temperature, a fin temperature, and an air blowing temperature is less than or equal to a predetermined value.   28. A refrigeration cycle device according to any of claims 16 to 24, further comprising a control unit (10, 17, 23, 24) for controlling the operation of the refrigerant cycle, wherein the refrigeration unit command initiates at least one of a cooling fan (2) for blowing air to a gas cooling device (3) and a compressor (8) of the refrigerant cycle when the condition is detected , and then the control unit stops at least one of the compressor and the cooling fan during operation when the control unit determines that a temperature in the engine compartment of the vehicle or a temperature in the vehicle interior is less than or equal to a predetermined value.   The refrigeration cycle device according to any one of claims 25 to 28, wherein, when a predetermined time has elapsed after at least one of the compressor of the refrigerant cycle and the cooling fan is stopped, the condition detection unit starts the detection.   The refrigeration cycle device according to any one of claims 25 to 28, wherein when the control unit determines that the refrigerant pressure in the refrigerant cycle is less than or equal to a predetermined value, after that unless one of the compressor (8) and the cooling fan (3) is stopped, the condition detection unit starts the detection.   31. A vehicle refrigeration cycle device according to any one of claims 25 to 28, wherein when the control unit determines that any of the refrigerant temperature in the refrigerant cycle reaches a predetermined value or that a post-evaporation temperature, a fin temperature or an air blowing temperature reaches a predetermined value after at least one of the compressor and the cooling fan is stopped, the condition detection unit starts the detection.   32. Refrigeration cycle device according to one of   any of claims 25 to 28, wherein   when the control unit determines that a temperature in the engine compartment of the vehicle or a temperature in the passenger compartment of the vehicle is less than or equal to a predetermined value after at least one of the compressor and the cooling fan is stopped, the condition detection unit starts the detection.   The refrigeration cycle device of any one of claims 1 to 32, wherein the refrigerant cycle uses a carbon dioxide-containing refrigerant as the main component.