JP2007308133A - Air conditioning device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To implement air-conditioning in a vehicle cabin with saved power, without giving an occupant the feeling of discomfort. <P>SOLUTION: When an auxiliary heater is not used and if a temperature of engine cooling water is not more than threshold value determined in advance according to a target blowoff temperature, a normal engine start request control is performed so as to prevent decrease in temperature of the engine cooling water as heat source in heating (204). When the auxiliary heater is used, an engine stop time is elongated by performing an engine-on request control with saved power wherein a threshold value of a water temperature is lower than that of a water temperature in the normal engine start request control (212). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner, and more particularly to a vehicle air conditioner mounted on a vehicle such as an electric vehicle that runs on a motor or a hybrid vehicle that stops an engine when the vehicle is stopped.

  2. Description of the Related Art Conventionally, there has been proposed a vehicle for improving fuel efficiency by performing idling stop control that stops idling to improve fuel efficiency when traveling is stopped at an intersection or the like. Further, in a vehicle equipped with an engine and a motor as a power source, when the vehicle stops traveling, the engine is stopped to improve fuel efficiency.

  On the other hand, since the vehicle air conditioner performs heating using the heat of engine cooling water, a desired heating effect cannot be obtained when the temperature of the cooling water is low. That is, in a vehicle that performs idling stop control as described above or a vehicle such as a hybrid vehicle that has a mode in which the engine is stopped and the vehicle is running while running, if the temperature of the cooling water decreases, the heating effect Can no longer be obtained.

  Therefore, in a hybrid vehicle or the like, the temperature of the cooling water is decreased by stopping the engine or starting the engine based on a predetermined threshold value of the engine cooling water temperature according to the target outlet temperature (TAO) of the vehicle air conditioner. Is suppressed to obtain a heating effect.

Further, in the hybrid vehicle as described above, in a cold region or the like, the engine may be restarted immediately after the engine is stopped to heat the vehicle interior, so the technique described in Patent Document 1 is used. Proposes to lower the blower level when the engine is stopped and when a seat heater or a PTC (Positive Temperature Coefficient) heater is used. By lowering the blower level in this way, the amount of heat taken from the engine cooling water from the heater core can be reduced, thereby suppressing the temperature drop of the engine cooling water and extending the engine stop time. , Fuel economy can be improved.
JP 2000-142095 A

  However, in the technique described in Patent Document 1, the blower level is lowered from the idea that heating can be performed to some extent when using an auxiliary heater such as a seat heater or a PTC heater, but the blower air volume changes immediately after the engine stops. Since the amount of heat received by the occupant changes due to the air blowing, the occupant may feel uncomfortable as soon as the engine is stopped.

  The present invention has been made in consideration of the above-described facts, and an object of the present invention is to air-condition the vehicle interior with power saving without giving a sense of incongruity to an occupant.

  In order to achieve the above object, the invention according to claim 1 is characterized in that air conditioning means for calculating a target blowing temperature of conditioned air for air conditioning the vehicle interior and air-conditioning the vehicle interior so as to be the target blowing temperature; A state quantity acquisition means for acquiring a state quantity corresponding to the temperature of the heat source heated by the heating means for heating the heat source during heating of the air conditioning means, and a passenger compartment provided separately from the air conditioning means for the passenger Detecting means for detecting whether or not an auxiliary heater for heating is used, and the state quantity acquired by the state quantity acquisition means is less than or equal to a threshold value of the state quantity predetermined according to the target blowing temperature In the case, the threshold value is changed to a small value when it is detected that the auxiliary heater is being used by the detecting means and the detecting means for requesting the heating means to heat the heat source. It is characterized in that it comprises further means, the.

  According to the first aspect of the present invention, the air conditioning means calculates the target blowing temperature of the conditioned air for air conditioning the passenger compartment, and air-conditions the passenger compartment so that the calculated target blowing temperature is obtained. At this time, the heating source of the air conditioning means is heated by the heating means.

  The state quantity acquisition unit acquires a state quantity corresponding to the temperature of the heat source heated by the heating unit. For example, an engine or a heat pump can be applied as the heating means. When an engine is applied as the heating means, the engine cooling water can be applied as a heat source during heating of the air conditioning means, and the engine cooling water temperature or the like can be applied as the state quantity. Further, when a heat pump is applied as the heating means, a heat exchanger or the like can be applied as a heat source during heating of the air conditioning means, and a heat radiation temperature or the like from the heat exchanger or the like can be applied as a state quantity. it can.

  Further, the detecting means detects whether or not an auxiliary heater for heating the passenger compartment provided separately from the air conditioning means is used for the passenger.

  Then, in the request unit, when the state quantity acquired by the state quantity acquisition unit is equal to or less than a threshold of a state quantity determined in advance according to the target blowing temperature, the heating unit is heated by the heating unit in order to maintain the heating capacity. A request for is made. In addition, as a request | requirement for heating a heat source to a heating means, when applying a heat pump as a heating means, you may make it perform the request | requirement of the operation | movement request | requirement of a heat pump, the rotation speed of a heat pump, etc., for example. Further, when an engine is applied as the heating means, an engine start request may be made.

  Further, when the detection unit detects that the auxiliary heater is being used when the heating unit is requested to heat the heat source, the change unit changes the threshold value of the state quantity to a small value, A request is made to heat the heat source to the heating means. That is, when the auxiliary heater is used, the passenger's sense of warmth is higher than the actual passenger compartment temperature, so it is difficult to understand even if the temperature of the heat source gradually decreases and the heating capacity of the air conditioning means decreases. Therefore, when using the auxiliary heater, the value is changed to a value smaller than the original threshold value, that is, the threshold value of the state quantity corresponding to the lower temperature, and a request for heating the heat source is made to the heating means. As a result, the vehicle interior can be air-conditioned by reducing the power of the operation of the heating means without causing the passenger to feel uncomfortable.

  According to a second aspect of the present invention, there is provided an air conditioning means for calculating a target blowing temperature of air-conditioned air for air-conditioning the vehicle interior and air-conditioning the vehicle interior so as to be the target blowing temperature, and a heat source during heating of the air-conditioning means; Acquisition means for acquiring the engine cooling water temperature, detection means for detecting whether or not an auxiliary heater for heating the passenger compartment provided separately from the air conditioning means is used for the occupant, and the acquisition means The auxiliary heater is used by the requesting means for making an engine start request and the detecting means when the water temperature obtained by the step is equal to or lower than a predetermined threshold of the water temperature according to the target blowing temperature. And changing means for changing the threshold value to a small value when it is detected.

  According to the second aspect of the present invention, the air conditioning means calculates the target blowing temperature of the conditioned air for air conditioning the passenger compartment, and air-conditions the passenger compartment so that the calculated target blowing temperature is obtained.

  In the acquisition means, the temperature of the engine coolant that is a heat source during heating of the air conditioning means is acquired.

  The detecting means detects whether or not an auxiliary heater for heating the passenger compartment provided separately from the air conditioning means is used for the passenger.

  Then, in the request unit, when the water temperature acquired by the acquisition unit is equal to or lower than a water temperature threshold value determined in advance according to the target blowing temperature, an engine start request is made to maintain the heating capacity. At this time, if the detection means detects that the auxiliary heater is being used, the change means changes the water temperature threshold value to a small value and makes an engine start request. That is, when the auxiliary heater is used, the passenger's sense of warmth is higher than the actual passenger compartment temperature, so it is difficult to understand even if the temperature of the heat source gradually decreases and the heating capacity of the air conditioning means decreases. Therefore, when the auxiliary heater is used, the engine start request is made by changing the value to a value smaller than the original threshold value, that is, a lower water temperature threshold value. As a result, the engine stop time can be extended without giving the passenger a sense of incongruity, so that the vehicle interior can be air-conditioned while saving power.

  As the auxiliary heater, for example, as in the invention described in claim 3, an occupant contact type heater (for example, a seat heater or a steering heater), an electric heater (a halogen heater, a radiation heater, a PTC heater, etc.), and At least one heater of the heat pump can be applied.

  When the auxiliary heater of the invention of claim 2 includes an electric heater such as a heat pump and a PTC heater, the changing means changes the threshold value to a small value as in the invention of claim 4. The threshold value may be changed so that the value when the heat pump is used is smaller than the value when the electric heater is used. That is, since an electric heater such as a PTC heater has a lower heating performance than a heat pump, it is possible to maintain the heating performance by facilitating starting the engine as a threshold value that is larger than when the heat pump is used.

  According to a fifth aspect of the present invention, there is provided air conditioning means for calculating a target blowing temperature of conditioned air for air-conditioning the passenger compartment and air-conditioning the passenger compartment so as to be the target blowing temperature, and a heat source during heating of the air-conditioning means, The acquisition means for acquiring the engine cooling water temperature, the heat pump and the electric heater for heating the passenger compartment provided separately from the air conditioning means for the occupant, and the water temperature acquired by the acquisition means, A request means for making an engine start request when the water temperature is equal to or lower than a predetermined water temperature threshold value according to a target blowing temperature, and when the outside air temperature is lower than a predetermined temperature, the electric heater is operated to reduce the threshold value. And changing means for changing the value to a value smaller than that when the electric heater is operated when the outside air temperature is equal to or higher than a predetermined temperature. It is set to.

  According to the fifth aspect of the present invention, the air conditioning means calculates the target blowing temperature of the conditioned air for air conditioning the passenger compartment, and air-conditions the passenger compartment so that the calculated target blowing temperature is obtained.

  In the acquisition means, the temperature of the engine coolant that is a heat source during heating of the air conditioning means is acquired.

  In addition, the heat pump and the electric heater are provided separately from the air conditioning means for the occupant to heat the passenger compartment.

  Further, in the request unit, when the water temperature acquired by the acquisition unit is equal to or lower than a water temperature threshold value determined in advance according to the target blowing temperature, an engine start request is made to maintain the heating capacity.

  In the changing means, when the outside air temperature is lower than the predetermined temperature, the electric heater is operated to change the threshold value to a small value, and when the outside air temperature is equal to or higher than the predetermined temperature, the heat pump is operated to set the threshold value to the electric heater. The value is changed to a value smaller than that during operation. In other words, when the heat pump or electric heater is operating, the passenger's feeling of warmth becomes higher than the actual passenger compartment temperature, so even if the temperature of the heat source gradually decreases and the heating capacity of the air conditioning means decreases. Since it becomes difficult to understand, when the heat pump or the electric heater is operated, the engine start request is made by changing the value to a value smaller than the original threshold value, that is, a lower water temperature threshold value. As a result, the engine stop time can be extended without giving the passenger a sense of incongruity, so that the vehicle interior can be air-conditioned while saving power.

  In addition, since an electric heater such as a PTC heater has a lower heating performance than a heat pump, it is possible to maintain the heating performance by facilitating starting the engine as a threshold value larger than that at the time of heat pump operation.

  As described above, according to the present invention, when the auxiliary heater is used, whether or not the auxiliary heater is used by utilizing the fact that the occupant's thermal sensation is higher than the actual passenger compartment temperature. Accordingly, there is an effect that the passenger compartment can be air-conditioned with power saving without giving a sense of incongruity to the passenger by making a request to heat the heat source for heating.

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

(First embodiment)
FIG. 1 is a block diagram showing a configuration of a vehicle air conditioner according to the first embodiment of the present invention. The vehicle air conditioner 10 according to the present embodiment will be described as being mounted on a hybrid vehicle and capable of air conditioning in the vehicle interior even when the engine is stopped.

  In the vehicle air conditioner 10 according to the first embodiment of the present invention, a refrigerant circulation path including a compressor 12, a condenser 14, an expansion valve 16, and an evaporator 18 constitutes a refrigeration cycle.

  The evaporator 18 cools the air passing through the evaporator 18 (hereinafter referred to as air after the evaporator) by evaporating the refrigerant that has been compressed and liquefied. At this time, the evaporator 18 cools the passing air so as to condense moisture in the air, whereby the air after the evaporator 18 is dehumidified.

  The expansion valve 16 provided on the upstream side of the evaporator 18 is configured to supply the liquefied refrigerant to the evaporator in a mist state by rapidly reducing the pressure of the liquefied refrigerant, whereby the refrigerant in the evaporator 18 is supplied. Vaporization efficiency is improved.

  In the present embodiment, the compressor 12 of the vehicle air conditioner 10 is an electric compressor so that the motor 20 can circulate the refrigerant even when the power of the vehicle (for example, an engine or a motor) is not operated. It is configured. When the vehicle power is operating, the compressor 12 may be driven by the vehicle power.

  The evaporator 18 of the vehicle air conditioner 10 is provided inside the air conditioning duct 22. The air conditioning duct 22 is open at both ends, and air inlets 24 and 26 are formed at one opening end. Further, a plurality of air outlets 28 (28A, 28B, and 28C are shown as an example in the present embodiment) opened toward the vehicle interior are formed at the other opening end.

  The air suction port 26 communicates with the outside of the vehicle and can introduce outside air into the air conditioning duct 22. Further, the air suction port 24 communicates with the vehicle interior, and air (inside air) can be introduced into the air conditioning duct 22 from the lower portion of the vehicle interior. In this embodiment, the air outlet 28 includes a defroster outlet 28A (DEF) that blows air toward the windshield glass, a side that can blow air toward the upper part of the vehicle interior, and a center register outlet 28B (Vent ), A foot outlet 28C (Heat) that blows out air toward the lower part of the vehicle interior.

  In the air conditioning duct 22, a blower fan 27 is provided between the evaporator 18 and the air suction ports 24 and 26. A suction port switching damper 30 is provided in the vicinity of the air suction ports 24 and 26. The suction port switching damper 30 exclusively opens and closes the air suction ports 24 and 26 by the operation of the suction port switching damper actuator 32.

  The blower fan 27 is rotated by driving of the blower motor 34, sucked into the air conditioning duct 22 from the air suction port 24 to the air suction port 26, and further sends this air toward the evaporator 18. At this time, outside air or inside air is introduced into the air conditioning duct 22 in accordance with the open / closed state of the air suction ports 24 and 26 by the suction port switching damper 30. That is, the inside air circulation mode and the outside air introduction mode are switched by the suction port switching damper 30.

  An air mix damper 36 and a heater core 38 are provided downstream of the evaporator 18. The air mix damper 36 is rotated by driving the air mix damper actuator 40 to adjust the amount of air after the evaporator 18 that passes through the heater core 38 and the amount that bypasses the heater core 38. The heater core 38 circulates engine cooling water, and heats the air guided by the air mix damper 36 using the heat of the engine cooling water heated by the engine.

  The air after the evaporator 18 is guided to the heater core 38 according to the opening degree of the air mix damper 36 and heated, and further mixed with the air not heated by the heater core 38 and then sent to the air outlet 28. Is done. In the vehicle air conditioner 10, the air mix damper 36 is controlled to adjust the mixed state of the cool air after the evaporator 18 and the warm air heated by the heater core 38, so that the air blower 28 is directed toward the vehicle interior. Adjust the temperature of the blown out air.

  In the vicinity of the air outlet 28, an outlet switching damper 42 is provided. In the vehicle air conditioner 10, the air outlets 28 </ b> A, 28 </ b> B, and 28 </ b> C are opened and closed by the outlet switching damper 42, so that the temperature-adjusted air can be blown out from a desired position into the vehicle interior. The operation of the air outlet switching damper 42 is performed by driving the air outlet switching damper actuator 44 in accordance with the operation mode in which the vehicle air conditioner 10 is set.

  The vehicle air conditioner 10 includes an air conditioner ECU (Electronic Control Unit) 46 for performing various controls of the vehicle air conditioner 10. The air conditioner ECU 46 rotationally drives a blower fan speed control device 48 that controls the rotational speed of the blower fan 27, an intake port switching damper actuator 32, an air mix damper actuator 40, an outlet switching damper actuator 44, and the compressor 12. A control switch 50 for controlling the motor 20, an outside air temperature sensor 52, a vehicle interior temperature sensor 54, a solar radiation sensor 56, and a post-evaporator temperature sensor 60 are connected, and the temperature setting of the vehicle air conditioner 10 and the outlet port 28 are connected. A temperature setting device 58 or the like for selection or the like is connected, and detected values of the outside air temperature sensor 52, the vehicle interior temperature sensor 54, the solar radiation sensor 56, and the post-evaporator temperature sensor 60 are input to the air conditioner ECU 46, and each sensor For setting the temperature setting device 58 based on the detected value Flip was adapted to perform various types of control. The blower fan speed control device 48 can be applied to a device such as a power transistor. When the power transistor is applied, the duty ratio of the voltage applied to the base of the power transistor is changed. It is possible to change the rotation speed.

  Further, an auxiliary heater 64 is provided in a vehicle on which the vehicle air conditioner 10 according to the present embodiment is mounted, and heating by the vehicle air conditioner 10 and heating by the auxiliary heater 64 are possible. An auxiliary heater 64 is connected to the air conditioner ECU 46 of the apparatus 10, and the usage status of the auxiliary heater 64 is input to the air conditioner ECU 46.

  Examples of the auxiliary heater 64 include an occupant contact type heater (a seat heater for heating a vehicle seat, a steering heater for heating a steering, etc.), an electric heater (a halogen heater, a radiation heater, a PTC heater, etc.), and a refrigerant cycle. An auxiliary heater such as a utilized heat pump can be applied, and the auxiliary heaters may be applied in combination.

  Furthermore, the engine ECU 62 is connected to the air conditioner ECU 46, and the detection result of the engine water temperature input to the engine ECU 62 can be acquired. The vehicle air conditioner 10 according to this embodiment is a vehicle such as a hybrid vehicle. If the engine is turned off when the motor is running or stopped and the engine cooling water temperature decreases, the amount of heat released from the heater core 38 decreases and the heating effect cannot be obtained. Based on the engine water temperature, an engine on request and an engine off request are made to the engine ECU 62.

  Specifically, the air conditioner ECU 46 stores an engine-on request threshold value and an engine-off request threshold value that are predetermined according to the target outlet temperature (TAO), and the engine-on request threshold value and the engine-off request threshold value. Based on the above, an engine on / off request is made to the engine ECU 62.

  Further, in the present embodiment, when the auxiliary heater 64 is used, the occupant's thermal sensation is higher than the actual room temperature, so that the threshold is changed according to the use of the auxiliary heater 64 using a different threshold. Engine-on request control. In the present embodiment, as shown in FIG. 2, a normal engine-on request threshold (when the auxiliary heater 64 is not used) for making an engine-on request at a predetermined engine water temperature according to the target blow-out temperature (FIG. 2). 2) and a power saving engine on request threshold (solid line in FIG. 2) for saving power by making an engine on request at an engine water temperature lower than the engine on request threshold are stored in the air conditioner ECU 46 in advance. The air conditioner ECU 46 performs normal engine-on request control using the normal engine-on request threshold and power-saving engine-on control using the power-saving engine-on request threshold according to the use of the auxiliary heater 64. Note that the lower side of the dotted line in FIG. 2 is the engine-on request region during normal engine-on request control, and similarly, the lower side of the solid line in FIG. 2 is the engine-on request region during power-saving engine-on request control.

  Next, the operation of the vehicle air conditioner 10 according to the first embodiment of the present invention configured as described above will be described.

  The vehicle air conditioner 10 according to the present embodiment performs air conditioning control (automatic air conditioning control) so as to keep the temperature in the passenger compartment at a preset value based on the detection result of each sensor. The air conditioner control will be described. FIG. 3 is a flowchart showing an example of the flow of automatic air conditioner control performed by the air conditioner ECU 46.

  When an air conditioning start instruction is issued by the temperature setting device 58 or the like, in step 100, detected values detected by respective sensor values such as the outside air temperature sensor 52, the vehicle interior temperature sensor 54, the solar radiation sensor 56, the post-evaporator temperature sensor 60, and the like. And the temperature set by the temperature setting device 58 are read.

  Subsequently, in step 102, the target blowing temperature (TAO) is calculated, and the routine proceeds to step 104. TAO is calculated using the following equation.

TAO = K1 * Tset-K2 * Tr-K3 * To-K4 * ST + C
Here, Tset is the set temperature, Tr is the passenger compartment temperature, To is the outside air temperature, ST is the amount of solar radiation, and K1, K2, K3, K4, and C are constants.

  In step 104, the opening degree of the air mix damper (A / M) 36 is calculated. Specifically, in order to control the blowout temperature to be the target blowout temperature, the mixing ratio (hot air / cold air) r, which is the ratio of the warm air passing through the heater core 38 and the cold air bypassing the heater core 38, is Calculated by the formula.

  r = (TAO−Te) / (Th−Te)

  Te represents the post-evaporator air temperature detected by a sensor provided after the evaporator 18, and Th represents the air temperature immediately after the heater core 38. In this embodiment, Th is calculated using the following equation.

  Th = A × Tw + (1−A) × Te

  Here, Tw indicates the temperature of the engine cooling water, and A indicates a constant of 1 or less.

  Next, the opening degree S of the air mix damper 36 at which the calculated mixing ratio r is obtained is calculated by the following equation.

  S = F1 (r)

  In addition, F1 (x) represents the function of the opening degree S of the air mix damper 36, and F1 (r) represents the opening degree of the air mix damper 36 in the case of the mixing ratio r.

  Next, at step 106, the air mix damper actuator 40 is driven so that the calculated opening of the air mix damper 36 is reached, and the routine proceeds to step 108.

  In step 108, the voltage to be applied to the blower motor 34 of the blower fan 27 is calculated from the target blow temperature in accordance with a predetermined map, and a signal is output to the blower fan speed control device 48, so as to correspond to the target blow temperature. The process proceeds to step 110.

  In step 110, it is determined whether the air conditioner is off. In this determination, it is determined whether or not the stop of air conditioning is instructed by the temperature setting device 58 or the like. If the determination is negative, the process returns to step 100 and the above processing is repeated, and the determination in step 110 is affirmative. When it is done, the process is terminated.

  By the way, since the vehicle air conditioner 10 according to the first embodiment of the present invention is mounted on a hybrid vehicle or the like, the engine may be stopped and run by a motor or the like. Since the heating effect is not obtained when the engine stop time is prolonged, the engine on / off request is output from the air conditioner ECU 46 to the engine ECU 62 to prevent the temperature of the engine cooling water from decreasing. Perform engine on / off request control.

  However, when the auxiliary heater 64 is used, the passenger's sense of warmth is higher than the actual room temperature, and it is not necessary to make an engine-on request, but the engine-on request is made to maintain the heating capacity of the vehicle air conditioner 10. The engine off time will be shortened. Therefore, in the present embodiment, the engine-on request control is performed by changing the engine-on request threshold according to the usage status of the auxiliary heater 64.

  FIG. 4 is a flowchart showing an example of a flow of engine-on request control performed by the air conditioner ECU 46 of the vehicle air conditioner 10 according to the first embodiment of the present invention. Note that the engine-on request control of FIG. 4 will be described as ending with the end of the automatic air conditioner control.

  When the above-described automatic air-conditioning control is started, in step 200, the usage status of the auxiliary heater 64 is detected, and the routine proceeds to step 202.

  In step 202, it is determined from the usage status of the auxiliary heater 64 detected in step 200 whether or not the auxiliary heater 64 is turned on. If the determination is negative, the process proceeds to step 204. Goes to step 206.

  In step 204, normal engine-on request control is performed, the process returns to step 100, and the above-described processing is repeated. That is, the target air temperature calculated in step 102 described above is acquired, the water temperature is acquired from the engine ECU 62, and based on the normal engine-on request threshold value when the auxiliary heater 64 indicated by the dotted line in FIG. 2 is not used. An engine-on request is made. As a result, the engine ECU 62 can start the engine upon receiving the engine-on request, thereby heating the cooling water and maintaining the heating.

  On the other hand, if the determination in step 202 is affirmed and the process proceeds to step 206, the outside air temperature and the vehicle interior temperature are detected from the detection results of the outside air temperature sensor 52 and the vehicle interior temperature sensor 54, and the process proceeds to step 208.

  In step 208, it is determined whether or not the outside air temperature is −6 ° C. or higher. If the determination is negative, the process proceeds to step 204 described above. If the determination is positive, the process proceeds to step 210.

  In step 210, it is determined whether the vehicle interior temperature is 20 ° C. or higher. If the determination is negative, the process proceeds to step 204 described above, and if the determination is affirmative, the process proceeds to step 212.

  In step 212, power saving control is performed, the process returns to step 200, and the above-described processing is repeated. That is, the target blowing temperature calculated in step 102 described above is acquired, the water temperature is acquired from the engine ECU 62, and an engine-on request is made based on the power-saving engine-on request threshold indicated by the solid line in FIG. As a result, the engine ECU 62 can start the engine upon receiving the engine-on request, thereby heating the cooling water and maintaining the heating. At this time, the power-saving engine-on request threshold is lower than the normal engine-on request threshold because the water temperature threshold determined according to the target outlet temperature is lower. Fuel consumption can be suppressed. Further, since the power saving engine on request threshold value is lower than the normal engine on request threshold value, the water temperature threshold value determined in accordance with the target blowing temperature is lower, so that the water temperature gradually decreases and the heating capacity of the vehicle air conditioner 10 is increased. Although the temperature is reduced, since the auxiliary heater 64 is used, the occupant's thermal sensation is higher than the actual passenger compartment temperature, making it difficult to recognize that the heating capacity gradually decreases, and as a result, heating is performed. Capability can be maintained, and fuel consumption can be improved by extending the engine stop time without giving the passenger a sense of incongruity.

  In the first embodiment, the engine cooling water is used as a heat source when air-conditioning the vehicle interior and the engine is used as a heating means for heating the heat source, and the engine-on request control is performed to secure the heat source. However, the present invention is not limited to this. For example, a heat pump using a refrigerant compressed by a compressor driven in accordance with the supplied power is used as a heating means, and a heat exchanger of the heat pump is used as a heat source. Instead, the compressor operation request control (compressor on request, compressor rotation speed change request, etc.) may be performed by detecting the temperature of the heat exchanger or the like of the heat pump. For example, in accordance with the target blow temperature setting map determined in advance according to the target blow temperature in the normal state (when the auxiliary heater 64 is not used) and the target blow temperature when the auxiliary heater 64 is used. The setting map is changed according to the use of the auxiliary heater 64 using the setting map of the compressor rotation speed (rotation speed lower than the case where the auxiliary heater 64 is not used) of the heat pump determined in advance. Compressor operation request control may be performed. In this case, since the power of the compressor of the heat pump is driven by electric power, it is possible to suppress the driving of the compressor at an unnecessarily high rotational speed, and it is possible to save power.

(Second Embodiment)
Then, the vehicle air conditioner concerning 2nd Embodiment of this invention is demonstrated.

  In the second embodiment, a case where a PTC heater is provided as the auxiliary heater 64 of the first embodiment and a heat pump is provided will be described. In the first embodiment, the use of the auxiliary heater 64 is detected. However, in the second embodiment, the air conditioner control ECU controls the PTC heater and the heat pump as the auxiliary heater 64.

  Since the basic structure of the vehicle air conditioner according to the second embodiment of the present invention is only different from the first embodiment in the refrigerant circulation cycle, only the difference will be described.

  FIG. 5 is a block diagram showing a configuration of a vehicle air conditioner according to the second embodiment of the present invention. In addition, about the same structure as 1st Embodiment, the same code | symbol is attached | subjected and demonstrated. Further, in FIG. 5, the parts described in the first embodiment are partially omitted.

  The refrigerant circulation cycle of the vehicle air conditioner 70 according to the second embodiment of the present invention includes a compressor 12, an indoor condenser 72, a three-way valve 74, an outdoor heat exchanger 76, a check valve 78, electromagnetic valves 80 and 82, The evaporator 18, the expansion valve 84, the tank 86, and the compressor 12 are included, and the refrigeration cycle and the heat pump cycle are switched by switching the three-way valve 74 and the two electromagnetic valves 80 and 82. In the case of a heat pump cycle, it functions as an auxiliary heater.

  In the case of the refrigeration cycle, the three-way valve 74 is switched to the outdoor heat exchanger 76 side, and the electromagnetic valve 82 is turned off and the electromagnetic valve 80 is turned on. Circulates. That is, the refrigerant compressed by the compressor 12 passes through the indoor condenser 72, the three-way valve 74, the outdoor heat exchanger (corresponding to the condenser 14 of the first embodiment) 76, the electromagnetic valve 80, the expansion valve 84, and the evaporator 18 in this order. Then return to tank 86.

  In the refrigeration cycle, the high-temperature and high-pressure refrigerant compressed by the compressor 12 is radiated by the outdoor heat exchanger 76 to become a high-pressure and low-temperature refrigerant, and is decompressed by the expansion valve 84, whereby the liquefied refrigerant is vaporized. As a result, the air passing through the evaporator 18 is cooled. At this time, the evaporator 18 cools the passing air so as to condense moisture in the air, whereby the air after the evaporator 18 is dehumidified.

  In the case of the heat pump cycle, the three-way valve 74 is switched to the check valve 78 side, the electromagnetic valve 82 is turned on, and the electromagnetic valve 80 is turned off. That is, the refrigerant compressed by the compressor 12 returns to the tank 86 through the indoor condenser 72, the three-way valve 74, the check valve 78, the outdoor heat exchanger 76, and the electromagnetic valve 82.

  In the heat pump cycle, the high-temperature and high-pressure refrigerant is decompressed by the check valve 78 and absorbed by the outdoor heat exchanger 76. Then, after returning to the tank 86, it is compressed by the compressor 12, becomes a high-temperature and high-pressure refrigerant, and is radiated by the indoor condenser 72.

  In the present embodiment, as in the first embodiment, the compressor 12 of the vehicle air conditioner 10 uses an electric compressor, and even when the vehicle power (for example, an engine or a motor) is not operated, the motor 20 The refrigerant can be circulated. When the vehicle power is operating, the compressor 12 may be driven by the vehicle power.

  An HVAC (Heating Ventilating Air-Conditioning) is provided in the air conditioning duct 22 of the vehicle air conditioner 70. The HVAC includes the evaporator 18, the indoor capacitor 72, the PTC heater 88, and the like. Note that the air conditioning duct 22 is only the addition of the indoor condenser 72 and the PTC heater 88 to the first embodiment, and since the basic configuration is the same, only the differences will be described and detailed description will be omitted.

  An air mix damper 36 is provided downstream of the evaporator 18 in the air conditioning duct 22, and a heater core 38, an indoor condenser 72, and a PTC heater 88 are provided downstream of the air mix damper 36. That is, the air after the evaporator 18 is heated by at least one of the heater core 38, the indoor condenser 72, and the PTC heater 88.

  Further, the vehicle air conditioner 70 according to the present embodiment includes an air conditioner ECU 47 for performing various controls of the vehicle air conditioner 70 as in the first embodiment. As in the first embodiment, the air conditioner ECU 47 includes a blower fan speed control device 48, a suction port switching damper actuator 32, an air mix damper actuator 40, a blowout port switching damper actuator 44, the motor 20 of the compressor 12, and the like. A temperature sensor 52, a vehicle interior temperature sensor 54, a solar radiation sensor 56, and a post-evaporator temperature sensor 60 are connected, and a temperature setting device 58 for setting the temperature of the vehicle air conditioner 10, selecting the outlet 28, and the like. The detected values of the outside air temperature sensor 52, the vehicle interior temperature sensor 54, the solar radiation sensor 56, and the post-evaporator temperature sensor 60 are input to the air conditioner ECU 46, and the temperature setting device 58 is controlled based on the detected values of each sensor. Various controls are performed in accordance with settings and the like.

  Further, a vehicle equipped with the vehicle air conditioner 70 according to the present embodiment is provided with a PTC heater 88 as an auxiliary heater, and heating by the vehicle air conditioner 10 and heating by the PTC heater 88 are possible. A PTC heater 88 is connected to the air conditioner ECU 46 of the vehicle air conditioner 10.

  Further, the engine ECU 62 is connected to the air conditioner ECU 46, and the detection result of the engine water temperature input to the engine ECU 62 can be acquired as in the first embodiment. Also in the present embodiment, since the vehicle air conditioner 70 is mounted on a vehicle such as a hybrid vehicle, when the engine is turned off at the time of traveling by the motor or at the time of stopping, the heater core decreases when the engine coolant temperature decreases. Since the amount of heat released from 38 is reduced and the heating effect cannot be obtained, an engine-on request and an engine-off request are made to the engine ECU 62 based on the engine water temperature.

  Specifically, the air conditioner ECU 46 stores an engine-on request threshold value and an engine-off request threshold value that are predetermined according to the target outlet temperature (TAO), and the engine-on request threshold value and the engine-off request threshold value. Based on the above, an engine on / off request is made to the engine ECU 62.

In the present embodiment, when the heat pump or the PTC heater 88 is used, the occupant's thermal sensation is higher than the actual room temperature. Therefore, according to the use of the heat pump or the PTC heater 88 using different threshold values. The engine-on request control is performed by changing the threshold value. In the present embodiment, as shown in FIG. 6, a normal engine-on request threshold (T ₀ ) for making an engine-on request at a predetermined engine water temperature according to the target outlet temperature, and the engine-on request threshold Engine-on request thresholds for saving power by making an engine-on request at a lower engine water temperature (the engine-on request threshold T ₂ when the PTC heater 88 is operated and the engine-on request threshold T ₁ when the heat pump is operated (T ₂ > T ₁ )) is stored in advance in the air conditioner ECU 46, and the air conditioner ECU 46 controls the normal engine on request control using the normal engine on request threshold and the normal engine on request threshold in accordance with the use of the heat pump or the PTC heater 88. Power-saving engine-on control using smaller engine-on request thresholds (T ₁ , T ₂ ) is performed.

  When the engine water temperature is lower than the normal engine-on request threshold, the heat pump is operated. When the target blowing temperature is higher than a predetermined value (X), the heat pump is fully operated. When the target blowing temperature is lower than the predetermined value (X), the heat pump is operated while being limited.

  Furthermore, when the outside air temperature is low, the compressor 12 may not function. In this case, heating using the PTC heater 88 is performed.

  Next, the operation of the vehicle air conditioner 70 according to the second embodiment of the present invention configured as described above will be described.

  Similarly to the first embodiment, the vehicle air conditioner 70 according to the present embodiment also performs air conditioning control (automatic air conditioner control) based on the detection results of the sensors so as to keep the temperature in the vehicle interior at a predetermined set value. . Since the automatic air conditioner control is the same as that of the first embodiment, a detailed description thereof is omitted.

  Further, since the vehicle air conditioner 70 according to the second embodiment is also mounted on a hybrid vehicle or the like, the engine may be stopped and the vehicle may be driven by a motor or the like. In this case, the heat of the engine cooling water is used. Since the heating effect cannot be obtained if the engine stop time becomes longer, the engine on / off request is output from the air conditioner ECU 47 to the engine ECU 62 to prevent the engine cooling water temperature from decreasing. Do. At this time, in the second embodiment, since the heat pump and the PTC heater 88 are provided, the engine-on request threshold value is changed according to the operation state.

  Here, the engine-on request threshold value changing process will be described. FIG. 7 is a flowchart showing an example of the flow of an engine-on request threshold change process performed by the air conditioner ECU 47 of the vehicle air conditioner 70 according to the second embodiment of the present invention.

  First, in step 300, it is determined by the air conditioner ECU 47 whether or not the blower is turned on. In this determination, it is determined whether or not a blower blow instruction has been issued by the temperature setting device 58 or the like. If the result is affirmative, the routine proceeds to step 302.

  In step 302, the air conditioner ECU 47 determines whether or not the outside air temperature is 0 ° C. or higher. The determination is made based on the detection result of the outside air temperature sensor 52. If the determination is affirmative, the process proceeds to step 304. If the determination is negative, the process proceeds to step 314.

In step 304, it is determined by the air conditioner ECU 47 whether or not the temperature TW of the engine cooling water is equal to or higher than a normal engine-on request threshold (T ₀ ). That is, it is determined whether or not the temperature of the engine coolant acquired from the engine ECU 62 is T _0. If the determination is affirmative, the process proceeds to step 306. If the determination is negative, an example process is returned. .

  In step 306, it is determined by the air conditioner ECU 47 whether or not the target outlet temperature (TAO) is equal to or higher than the predetermined temperature (X). If the determination is affirmative, the process proceeds to step 308. If the determination is negative, the process proceeds to step 310. Transition.

  In step 308, the heat pump is operated while being limited by the air conditioner ECU 47, and the process proceeds to step 312. That is, the heat pump is driven while the rotation speed of the compressor 12 is limited.

  In step 310, the heat pump is fully operated by the air conditioner ECU 47, and the process proceeds to step 312. That is, when the target blowout temperature TAO is high, priority is given to the heating performance.

In step 312, the series of processes is returned after the engine-on request threshold has been changed to T _1. That is, usually more engine-on request threshold T ₀ engine-on request thresholds T ₁ than is the threshold of the water temperature determined according to the target discharge temperature is lower, it is possible to increase the time the engine is stopped, Wasteful fuel consumption can be suppressed. Also, usually more engine-on request threshold T ₀ engine-on request thresholds T ₁ than is the target outlet air due to the low threshold water temperature determined according to the temperature, the heating of the vehicle air conditioner 70 decreases water temperature is gradually Although the capacity is reduced, since the heat pump is used, it is possible to improve the fuel efficiency by extending the engine stop time while maintaining the heating capacity.

  On the other hand, in step 314, it is determined by the air conditioner ECU 47 whether the power generation amount is equal to or greater than a predetermined value. The determination is performed by obtaining the difference between the used power and the generated power amount from the engine ECU 62 and determining whether the difference between the used power and the generated power amount is a predetermined value or more. If the PTC heater 88 is used, the battery will rise, so the process is returned as it is, and if the determination is affirmative, the routine proceeds to step 316.

In step 316, it is determined by the air conditioner ECU 47 whether or not the temperature TW of the engine cooling water is equal to or higher than a normal engine-on request threshold (T ₀ ). That is, it is determined whether or not the temperature of the engine coolant acquired from the engine ECU 62 is T _0. If the determination is negative, the process proceeds to step 318, and if the determination is positive, a series of processing is returned. .

  In step 318, the PTC heater 88 is operated by the air conditioner ECU 47, and the routine proceeds to step 320.

In step 320, the series of processes is returned after the engine-on request threshold has been changed to T _2. That is, usually more engine-on request threshold T ₀ engine-on request threshold T ₂ than is the threshold of the water temperature determined according to the target discharge temperature is lower, it is possible to increase the time the engine is stopped, Wasteful fuel consumption can be suppressed. Also, usually more engine-on request threshold T ₀ engine-on request threshold T ₂ than is the target outlet air due to the low threshold water temperature determined according to the temperature, the heating of the vehicle air conditioner 70 decreases water temperature is gradually Although the capacity is lowered, the PTC heater 88 is operated, so that the engine stop time can be extended while maintaining the heating capacity, and the fuel consumption can be improved.

As described above, in the vehicle air conditioner 70 according to the present embodiment, the compressor 12 is operated when the outside air temperature is high (0 ° C. or higher). Therefore, the heat pump is driven using the compressor 12 to perform heating. Since the engine-on request threshold value is changed to a value smaller than the normal engine request threshold value T _0, the fuel consumption can be improved by extending the engine stop time while maintaining heating. In addition, when the target blowing temperature is lower than the predetermined value X, the compressor 12 operates with the electric power limited, so that it is possible to suppress the driving of the compressor 12 at an unnecessarily high rotational speed and to save power. Can do.

Further, when the outside air temperature is low (lower than 0 ° C.), the compressor 12 may not function. Therefore, the PTC heater 88 is operated to perform heating, and the engine-on request threshold is set to be higher than the normal engine request threshold T _0. Since the value is changed to a smaller value, the fuel consumption can be improved by extending the engine stop time while maintaining heating. Further, since the heating capacity is lower when the PTC heater 88 is used than when the heat pump is used, the engine-on request threshold value is set to T ₂ higher than T ₁ , so that a decrease in heating capacity can be suppressed. Furthermore, since power is consumed when the PTC heater 88 is used, it is possible to suppress the battery from running out by using the PTC heater 88 only when the difference between the used power and the amount of power generation is equal to or greater than a predetermined value.

In the second embodiment, the air conditioner ECU 47 operates the heat pump and the PTC heater 88 to change the engine-on request threshold according to the outside air temperature. However, the present invention is not limited to this. For example, the heat pump or the PTC The heater 88 is operated by a switch or the like, and the operation of the heat pump or the PTC heater 88 is detected like the auxiliary heater 64 of the first embodiment, and the engine-on request threshold is changed when the operation is detected. You may do it. As described in the second embodiment, the engine-on request threshold in this case is (normal engine-on request threshold T ₀ )> (engine-on request threshold T ₂ when the PTC heater 88 is operated)> (engine when the heat pump is operated) ON request threshold value T ₁ ).

It is a block diagram which shows the structure of the vehicle air conditioner concerning 1st Embodiment of this invention. In the vehicle air conditioner according to the first embodiment of the present invention, an example of a normal engine-on request threshold for making an engine-on request at a predetermined engine water temperature according to a target outlet temperature and an example of a power-saving engine-on request threshold FIG. It is a flowchart which shows an example of the flow of the automatic air-conditioner control performed by air-conditioner ECU. It is a flowchart which shows an example of the flow of the engine-on request | requirement control performed by air conditioner ECU of the vehicle air conditioner concerning 1st Embodiment of this invention. It is a block diagram which shows the structure of the vehicle air conditioner concerning 2nd Embodiment of this invention. In the vehicle air conditioner according to the second embodiment of the present invention, a normal engine-on request threshold value for making an engine-on request at a predetermined engine water temperature according to a target outlet temperature, and a water temperature lower than the normal engine-on request threshold value It is a figure which shows an example of the engine-on request | requirement threshold value for making an engine-on request | requirement by. It is a flowchart which shows an example of the flow of a change process of the engine-on request | requirement threshold value performed by air-conditioner ECU of the vehicle air conditioner concerning 2nd Embodiment of this invention.

Explanation of symbols

10, 70 Vehicle air conditioner 38 Heater core 46, 47 Air conditioner ECU
52 Outside air temperature sensor 54 Car interior temperature sensor 56 Solar radiation sensor 58 Temperature setting device 60 Temperature sensor after evaporator 62 Engine ECU
64 Auxiliary heater 72 Indoor condenser 74 Three-way valve 76 Outdoor heat exchanger 78 Check valve 80, 82 Solenoid valve 84 Expansion valve 86 Tank 88 PTC heater

Claims (5)

Air-conditioning means for calculating a target blowing temperature of the conditioned air for air-conditioning the passenger compartment and air-conditioning the passenger compartment so as to be the target outlet temperature;
State quantity acquisition means for acquiring a state quantity corresponding to the temperature of the heat source heated by the heating means for heating the heat source during heating of the air conditioning means;
Detecting means for detecting whether or not an auxiliary heater for heating the passenger compartment provided separately from the air conditioning means is used for an occupant;
Requesting means for making a request for heating the heat source to the heating means when the state quantity acquired by the state quantity acquiring means is equal to or less than a threshold value of the state quantity determined in advance according to the target blowing temperature; ,
Changing means for changing the threshold value to a small value when the detecting means detects that the auxiliary heater is being used;
A vehicle air conditioner comprising Air conditioning means for calculating a target blowing temperature of the conditioned air for air-conditioning the passenger compartment and air-conditioning the passenger compartment so as to be the target outlet temperature;
An acquisition means for acquiring a water temperature of engine cooling water that becomes a heat source during heating of the air conditioning means;
Detecting means for detecting whether or not an auxiliary heater for heating the passenger compartment provided separately from the air conditioning means is used for an occupant;
Request means for making an engine start request when the water temperature acquired by the acquisition means is equal to or lower than a threshold value of the water temperature determined in advance according to the target outlet temperature;
Changing means for changing the threshold value to a small value when the detecting means detects that the auxiliary heater is being used;
A vehicle air conditioner comprising   3. The vehicle air conditioner according to claim 1, wherein the auxiliary heater includes at least one heater of an occupant contact type heater, an electric heater, and a heat pump.   The auxiliary heater includes a heat pump and an electric heater, and when the threshold value is changed to a small value, the changing means changes the threshold value so that the value when using the heat pump is smaller than when the electric heater is used. The vehicle air conditioner according to claim 2, wherein: Air conditioning means for calculating a target blowing temperature of the conditioned air for air-conditioning the passenger compartment and air-conditioning the passenger compartment so as to be the target outlet temperature;
An acquisition means for acquiring a water temperature of engine cooling water that becomes a heat source during heating of the air conditioning means;
A heat pump and an electric heater for heating the passenger compartment provided separately from the air conditioning means for the occupant;
Request means for making an engine start request when the water temperature acquired by the acquisition means is equal to or lower than a threshold value of the water temperature determined in advance according to the target outlet temperature;
When the outside air temperature is lower than a predetermined temperature, the electric heater is operated to change the threshold value to a small value, and when the outside air temperature is equal to or higher than the predetermined temperature, the heat pump is operated to operate the electric heater. Change means for changing to a smaller value,
A vehicle air conditioner comprising

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