JP2014024371A - Vehicle air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve passenger's comfortability by speeding up the rising of heating of a heat pump device.SOLUTION: An air-conditioning control device estimates whether a high-pressure-side refrigerant temperature of a heat pump device is equal to or lower than a predetermined low temperature, and controls an air-conditioning unit to make an amount of the air blown to an in-vehicle heat exchanger smaller than that in a case of estimating the refrigerant temperature is higher than the predetermined low temperature if estimating that the refrigerant temperature is equal to or lower than the predetermined low temperature.

Description

  The present invention relates to a vehicle air conditioner mounted on a vehicle.

  2. Description of the Related Art Conventionally, an air conditioner including a heat pump device is known as an air conditioner mounted on, for example, a hybrid vehicle or an electric vehicle. These vehicle heat pump devices connect an electric compressor, a vehicle exterior heat exchanger disposed outside the vehicle interior, an expansion valve, and a vehicle interior heat exchanger disposed in the vehicle interior in order by refrigerant piping. Configured.

  For example, a vehicle air conditioner disclosed in Patent Document 1 includes, as a vehicle interior heat exchanger, an upstream vehicle interior heat exchanger disposed on the upstream side in the air flow direction and a downstream vehicle interior heat disposed on the downstream side. And an exchange. The downstream-side vehicle interior heat exchanger acts as a radiator in both the heating operation mode and the cooling operation mode. In addition, the upstream side vehicle interior heat exchanger acts as a heat absorber in both the heating operation mode and the cooling operation mode.

  Further, as disclosed in Patent Document 2, for example, a configuration is also known in which an upstream side interior heat exchanger also acts as a radiator in a heating operation mode. That is, the refrigerant pipe is connected so that the refrigerant discharged from the compressor flows through the downstream side interior heat exchanger and then flows through the upstream side interior heat exchanger. Thereby, since the air heated with the upstream vehicle interior heat exchanger can be reheated with a downstream vehicle interior heat exchanger, there exists an advantage that heating capability can be improved. On the other hand, in the cooling operation mode, by supplying the decompressed refrigerant to the upstream side vehicle interior heat exchanger, the upstream side vehicle interior heat exchanger is caused to act as a heat absorber, so that cooling can also be performed.

Japanese Patent Laid-Open No. 9-240266 JP 2011-255735 A

  By the way, heating of the vehicle may be started in a situation where the outside air temperature is low and the refrigerant on the high pressure side of the heat pump device is cooled down to near the outside air temperature, for example, as in winter.

  However, when the heating operation is started in such a situation, the air temperature blown to the vehicle interior heat exchanger is in a low state, so that the refrigerant discharged from the compressor flows into the vehicle heat exchanger while flowing through the vehicle interior heat exchanger. The temperature decreases due to heat exchange, and the refrigerant whose temperature has decreased is sucked into the compressor again. As a result, the pressure and temperature of the refrigerant are unlikely to rise when heating is started, and the time required for supplying warm air to the passenger compartment becomes longer due to the slow start of heating, which impairs passenger comfort. There is a problem.

  The present invention has been made in view of such a point, and an object of the present invention is to improve the comfort of passengers by speeding up the heating of the heat pump device.

  In order to achieve the above object, in the present invention, when heating is started, the amount of air blown to the vehicle interior heat exchanger serving as a radiator is reduced.

A first invention includes a heat pump device including a compressor that compresses a refrigerant, a vehicle interior heat exchanger disposed in a vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior;
A vehicle interior air conditioning unit configured to house the vehicle interior heat exchanger and to have a blower that blows air for air conditioning in the vehicle interior heat exchanger and to generate conditioned air and supply the conditioned air to the vehicle interior; A vehicle air conditioner comprising:
An air flow rate changing means for changing the air flow rate to the vehicle interior heat exchanger;
An air conditioning control device for controlling the air flow rate changing means,
The air conditioning control device performs heating start-up control for controlling the air flow rate changing means at the start of heating so that the air flow rate to the vehicle interior heat exchanger is smaller than when a predetermined time has elapsed after the start of heating. It is comprised so that it may perform.

  According to this configuration, since the amount of air blown to the vehicle interior heat exchanger is reduced at the start of heating, the outside air temperature is low as in, for example, winter, and the refrigerant on the high pressure side of the heat pump device is left outside for a long time. In the situation where it is cooled to the vicinity, it is possible to reduce the amount of heat exchanged with the external air when the refrigerant discharged from the compressor flows through the vehicle interior heat exchanger. Therefore, since the temperature fall of a refrigerant | coolant is suppressed, the raise of the refrigerant | coolant pressure and temperature of the high voltage | pressure side of a heat pump apparatus will become quick, and the start-up of heating will become quick.

A second invention includes a heat pump device including a compressor for compressing a refrigerant, a vehicle interior heat exchanger disposed in a vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior;
A vehicle interior air conditioning unit configured to house the vehicle interior heat exchanger and to have a blower that blows air for air conditioning in the vehicle interior heat exchanger and to generate conditioned air and supply the conditioned air to the vehicle interior; A vehicle air conditioner comprising:
An air flow rate changing means for changing the air flow rate to the vehicle interior heat exchanger;
An air conditioning control device for controlling the air flow rate changing means,
The air conditioning control device estimates whether or not the refrigerant temperature on the high pressure side of the heat pump device is equal to or lower than a predetermined low temperature. It is configured to perform heating start-up control for controlling the air flow rate changing means so that the air flow rate to the vehicle interior heat exchanger is smaller than that estimated to be high. To do.

  According to this configuration, in a situation where the outside air temperature is low and the refrigerant on the high pressure side of the heat pump device is cooled to near the outside air temperature, for example, in winter, the refrigerant temperature on the high pressure side is predetermined. It is estimated that the temperature is below the low temperature. In this case, since the amount of air blown to the vehicle interior heat exchanger is reduced, it is possible to reduce the amount of heat exchanged with the external air when the refrigerant discharged from the compressor flows through the vehicle interior heat exchanger. . Therefore, since the temperature fall of a refrigerant | coolant is suppressed, the raise of the refrigerant | coolant pressure and temperature of the high voltage | pressure side of a heat pump apparatus will become quick, and the start-up of heating will become quick.

According to a third aspect of the present invention, there is provided a compressor for compressing a refrigerant, a first vehicle interior heat exchanger and a second vehicle interior heat exchanger disposed in the vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior. A heat pump device comprising:
The first vehicle interior heat exchanger and the second vehicle interior heat exchanger are accommodated, and the air conditioner air is blown to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger. A vehicle interior air conditioning unit configured to generate and supply air to the vehicle interior;
A vehicle air conditioner comprising the heat pump device and an air conditioning control device for controlling the vehicle interior air conditioning unit,
The vehicle interior air conditioning unit includes an air flow rate changing means for changing the air flow rate to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger, and the air flow rate changing means is controlled by the air conditioning control device. And
The heat pump device is set to a heating operation mode in which the air conditioning control device uses the first vehicle interior heat exchanger and the second vehicle interior heat exchanger as radiators and the vehicle exterior heat exchanger functions as a heat absorber. Configured to
The air conditioning control device starts up the heating to control the air flow rate changing means so that the air flow rate to the first vehicle interior heat exchanger is smaller at the start of heating than when a predetermined time has elapsed after the start of heating. Some are configured to perform control.

  According to this configuration, since the amount of air blown to the first vehicle interior heat exchanger is reduced at the start of heating, when the refrigerant discharged from the compressor flows through the first and second vehicle interior heat exchangers, external air and The amount of heat exchange can be reduced compared to the case where a large amount of external air is blown to both the first and second vehicle interior heat exchangers. Therefore, since the temperature drop of the refrigerant is suppressed, the rise of the refrigerant pressure and temperature on the high pressure side of the heat pump device is accelerated, and the start-up of heating is accelerated.

  Further, in the heating operation mode, since both the first and second vehicle interior heat exchangers are heat radiators, a high heating capacity can be obtained.

4th invention is the compressor which compresses a refrigerant | coolant, the 1st vehicle interior heat exchanger and 2nd vehicle interior heat exchanger which are arrange | positioned in a vehicle interior, and the vehicle exterior heat exchanger arrange | positioned outside a vehicle interior A heat pump device comprising:
The first vehicle interior heat exchanger and the second vehicle interior heat exchanger are accommodated, and the air conditioner air is blown to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger. A vehicle interior air conditioning unit configured to generate and supply air to the vehicle interior;
A vehicle air conditioner comprising the heat pump device and an air conditioning control device for controlling the vehicle interior air conditioning unit,
The vehicle interior air conditioning unit includes an air flow rate changing means for changing the air flow rate to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger, and the air flow rate changing means is controlled by the air conditioning control device. And
The heat pump device is set to a heating operation mode in which the air conditioning control device uses the first vehicle interior heat exchanger and the second vehicle interior heat exchanger as radiators and the vehicle exterior heat exchanger functions as a heat absorber. Configured to
The air conditioning control device estimates whether or not the refrigerant temperature on the high pressure side of the heat pump device is equal to or lower than a predetermined low temperature. It is configured to perform heating start-up control for controlling the air flow rate changing means so that the air flow rate to the first vehicle interior heat exchanger is smaller than that estimated to be high. It is a feature.

  According to this structure, when it is estimated that the refrigerant | coolant temperature of the high voltage | pressure side of a heat pump apparatus is below predetermined low temperature, the ventilation volume to the said 1st vehicle interior heat exchanger becomes small. Therefore, when the refrigerant discharged from the compressor flows through the first and second vehicle interior heat exchangers, the amount of heat exchanged with the external air is increased in both the first and second vehicle interior heat exchangers. It becomes possible to reduce compared with the case where it ventilates. Therefore, since the temperature drop of the refrigerant is suppressed, the rise of the refrigerant pressure and temperature on the high pressure side of the heat pump device is accelerated, and the start-up of heating is accelerated.

  Further, in the heating operation mode, since both the first and second vehicle interior heat exchangers are heat radiators, a high heating capacity can be obtained.

According to a fifth invention, in any one of the first to fourth inventions,
The air flow rate changing means is a door for switching the air flow direction inside the vehicle interior air conditioning unit.

  According to this configuration, the air flow rate can be easily and reliably switched.

6th invention is equipped with the outside temperature sensor which detects the temperature outside a vehicle interior in any one invention of 1-5,
When the air temperature outside the passenger compartment is lower than a predetermined temperature based on the air temperature outside the passenger compartment detected by the outside air temperature sensor, the air conditioning control device determines that the refrigerant temperature on the high-pressure side of the heat pump device is lower than a predetermined low temperature. It is characterized by being configured to be estimated as follows.

  That is, the temperature outside the passenger compartment is related to the refrigerant temperature on the high-pressure side of the heat pump device, and the refrigerant temperature on the high-pressure side of the heat pump device is lower when the temperature outside the passenger compartment is lower. Therefore, the estimation result becomes accurate by detecting the temperature outside the passenger compartment and estimating the refrigerant temperature on the high-pressure side of the heat pump device.

A seventh invention is the invention according to any one of the first to fifth aspects,
A refrigerant temperature sensor for detecting the refrigerant temperature;
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the refrigerant temperature detected by the refrigerant temperature sensor has become higher than a predetermined temperature after heating start-up control. It is comprised so that it may be comprised.

  According to this configuration, since the actual refrigerant temperature is detected and switched to the normal heating based on the detected temperature, the normal heating can be performed at an appropriate timing after the start of the heating.

According to an eighth invention, in any one of the first to fifth inventions,
A refrigerant pressure detection sensor for detecting the refrigerant pressure;
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the refrigerant pressure detected by the refrigerant pressure sensor has become higher than a predetermined pressure after heating start-up control. It is comprised so that it may be comprised.

  According to this configuration, since the actual refrigerant temperature is pressurized and switched to normal heating based on the pressure, normal heating can be performed at an appropriate timing after the start of heating.

According to a ninth invention, in any one of the first to fifth inventions,
It has an air temperature sensor that detects the air temperature after passing through the vehicle interior heat exchanger,
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the air temperature detected by the air temperature sensor has become higher than a predetermined temperature after heating start-up control. It is comprised so that it may be comprised.

  According to this configuration, it is possible to accurately estimate whether or not the refrigerant temperature is rising by detecting the air temperature after passing through the vehicle interior heat exchanger. And since it switched to normal heating based on the air temperature after passing a vehicle interior heat exchanger, normal heating can be performed now at the appropriate timing which started the heating.

In a tenth aspect of the present invention based on any one of the first to fifth aspects,
The air conditioning control device is configured to switch the heat pump device and the vehicle interior air conditioning unit to normal heating control after a predetermined time has elapsed since the start of heating start-up control.

  According to this configuration, since the switching to the normal heating is performed based on the time elapsed since the start-up control of the heating is started, the normal heating can be performed at an appropriate timing while performing simple control.

In an eleventh aspect based on the tenth aspect,
The air-conditioning control device is configured to change the time between the start of heating start-up control and switching to normal heating control in accordance with the temperature outside the passenger compartment.

  For example, when the outside air temperature is low as in the extremely cold season, it may be considered that the time required for starting up the heating becomes longer. In this case, normal heating can be performed at an appropriate timing by increasing the time between the start of the heating start-up control and switching to the normal heating operation.

In a twelfth aspect based on the tenth aspect,
The air conditioning control device is configured to change the time between the start of heating start-up control and switching to normal heating control in accordance with the refrigerant pressure on the high pressure side.

  In other words, when the time required to start up the heating is prolonged, the time between the start of the heating start-up control and the switching to the normal heating operation is lengthened according to the refrigerant pressure, so that the time is appropriate. Normal heating can be performed.

  According to the first aspect of the invention, the amount of air blown to the vehicle interior heat exchanger is reduced at the start of heating, so that the start-up of heating can be speeded up, and thus passenger comfort can be improved. .

  According to the second invention, when the refrigerant temperature on the high pressure side of the heat pump device is estimated to be equal to or lower than a predetermined low temperature, the amount of air blown to the vehicle interior heat exchanger is reduced. The speed can be increased, and thus the comfort of the passenger can be improved.

  According to the third aspect of the invention, the amount of air blown to the first vehicle interior heat exchanger can be reduced at the start of heating, so that the start-up of heating can be speeded up, and thus passenger comfort is improved. Can do. Moreover, at the time of heating operation mode, a high heating capability can be obtained by making both the 1st and 2nd vehicle interior heat exchangers act as a radiator, and this can also improve a passenger | crew's comfort. .

  According to the fourth invention, when the refrigerant temperature on the high-pressure side of the heat pump device is estimated to be equal to or lower than the predetermined low temperature, the amount of air blown to the first vehicle interior heat exchanger can be reduced. The start-up can be made faster, and therefore passenger comfort can be improved. Moreover, at the time of heating operation mode, a high heating capability can be obtained by making both the 1st and 2nd vehicle interior heat exchangers act as a radiator, and this can also improve a passenger | crew's comfort. .

  According to the fifth aspect, by using the door, it is possible to easily and reliably switch the air flow rate.

  According to the sixth aspect of the invention, since the refrigerant temperature on the high pressure side of the heat pump device is estimated based on the temperature outside the passenger compartment, it is possible to obtain an accurate estimation result and thereby perform appropriate control. it can.

  According to the seventh invention, since the refrigerant temperature is detected and the heating start-up control is switched to the normal heating control based on the refrigerant temperature, the normal heating can be performed at an appropriate timing. Comfort can be further improved.

  According to the eighth invention, the refrigerant pressure is detected, and the heating start-up control is switched to the normal heating control based on the refrigerant pressure. Therefore, the normal heating can be performed at an appropriate timing, and the passenger's Comfort can be further improved.

  According to the ninth invention, the air temperature after passing through the vehicle interior heat exchanger is detected, and the heating start-up control is switched to the normal heating control based on the air temperature. Usually, heating can be performed, and passenger comfort can be further improved.

  According to the tenth aspect of the invention, since the heating start-up control is started and switched to the normal heating control after a lapse of a predetermined time, the normal heating can be performed at an appropriate timing while performing simple control. The comfort can be further improved.

  According to the eleventh aspect of the invention, the time between the start of the heating start-up control and the switching to the normal heating control is changed according to the outside air temperature, so that the normal heating is performed at an appropriate timing according to the outside air temperature. This can be performed, and passenger comfort can be further improved.

  According to the twelfth aspect, since the time between the start of the heating start-up control and the switching to the normal heating control is changed according to the refrigerant pressure on the high pressure side, the normal heating is performed at an appropriate timing. This can further improve passenger comfort.

It is a schematic block diagram of the vehicle air conditioner concerning Embodiment 1. FIG. It is a block diagram of a vehicle air conditioner. It is the perspective view which looked at the downstream vehicle interior heat exchanger from the air flow direction upstream. It is a front view of a vehicle exterior heat exchanger. FIG. 2 is a view corresponding to FIG. 1 in a heating start-up operation mode. FIG. 2 is a view corresponding to FIG. 1 when in a heating operation mode. FIG. 2 is a view corresponding to FIG. 1 when in a cooling operation mode. FIG. 2 is a view corresponding to FIG. 1 when in a defrosting operation mode. It is a flowchart which shows the control procedure by an air-conditioning control apparatus. It is a flowchart which shows the heating subroutine control procedure concerning Embodiment 1. FIG. It is a flowchart which shows the heating subroutine control procedure concerning Embodiment 2. FIG. It is a flowchart which shows the heating subroutine control procedure concerning Embodiment 3.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a vehicle air conditioner 1 according to a first embodiment of the present invention. The vehicle on which the vehicle air conditioner 1 is mounted is an electric vehicle including a traveling storage battery and a traveling motor.

  The vehicle air conditioner 1 includes a heat pump device 20, a vehicle interior air conditioning unit 21, and an air conditioning control device 22 (shown in FIG. 2) that controls the heat pump device 20 and the vehicle interior air conditioning unit 21.

  The heat pump device 20 includes an electric compressor 30 that compresses a refrigerant, a downstream side vehicle interior heat exchanger (first vehicle interior heat exchanger) 31 disposed in the vehicle interior, and a downstream vehicle interior heat exchanger in the vehicle interior. 31, an upstream-side vehicle interior heat exchanger (second vehicle interior heat exchanger) 32 disposed on the upstream side in the air flow direction of the vehicle 31, an exterior heat exchanger 33 disposed outside the vehicle interior, an accumulator 34, 1st-4th main refrigerant | coolant piping 40-43 which connects these apparatuses 30-34, and 1st-3rd branch refrigerant | coolant piping 44-46 are provided.

  The electric compressor 30 is a conventionally well-known vehicle-mounted one, and is driven by an electric motor. By changing the rotation speed of the electric compressor 30, the discharge amount per unit time can be changed. The electric compressor 30 is connected to the air conditioning control device 22 so as to be switched between ON and OFF and to control the rotation speed. Electric power is supplied to the electric compressor 30 from the traveling storage battery.

  As shown in FIG. 3, the downstream-side vehicle interior heat exchanger 31 includes an upper header tank 47, a lower header tank 48, and a core 49. The core 49 is formed by integrating tubes 49a and fins 49b extending in the vertical direction alternately in the left-right direction (left-right direction in FIG. 3), and the air for air-conditioning passes between the tubes 49a. ing. The flow direction of the air-conditioning air is indicated by white arrows. The tubes 49a are arranged in two rows in the air flow direction.

  The upper ends of the air flow upstream tube 49 a and the downstream tube 49 a are connected to and communicate with the upper header tank 47. Inside the upper header tank 47, a first partition portion 47a that partitions the upper header tank 47 into an upstream side and a downstream side in the air flow direction is provided. The space upstream of the first partition 47a in the air flow direction communicates with the upper end of the upstream tube 49a, and the space downstream of the first partition 47a in the air flow direction communicates with the upper end of the downstream tube 49a. doing.

  In addition, a second partition portion 47 b that partitions the upper header tank 47 in the left-right direction is provided inside the upper header tank 47. A communication hole 47e is formed on the first partition 47a on the right side of the second partition 47b.

  A refrigerant inflow port 47 c is formed on the left side of the upper header tank 47 on the downstream side of the air flow, and a refrigerant outflow port 47 d is formed on the upstream side.

  Inside the lower header tank 48, similarly to the first partition portion 47 a of the upper header tank 47, a partition portion 48 a that partitions the upstream side and the downstream side in the air flow direction is provided. A space upstream of the partition portion 48a in the air flow direction communicates with the lower end of the upstream tube 49a, and a space downstream of the partition portion 48a in the air flow direction communicates with the lower end of the downstream tube 49a.

  The downstream side vehicle interior heat exchanger 31 has a total of four paths by being configured as described above. That is, the refrigerant flowing in from the inlet 47c first flows into the space R1 on the downstream side of the first partition 47a of the upper header tank 47 in the air flow direction and on the left side of the second partition 47b. It flows downward in the tube 49a communicating with R1.

  Then, after flowing into the space S1 downstream of the partition 48a of the lower header tank 48 in the air flow direction, flowing to the right and flowing upward in the tube 49a, the first partition of the upper header tank 47 It flows into the space R2 on the downstream side in the air flow direction from 47a and on the right side of the second partition 47b.

  Next, the refrigerant in the space R2 passes through the communication hole 47e of the first partition 47a, is upstream of the first partition 47a of the upper header tank 47 in the air flow direction, and is on the right side of the second partition 47b. It flows into the space R3 and flows downward in the tube 49a communicating with the space R3.

  Then, after flowing into the space S2 upstream of the partition portion 48a of the lower header tank 48 in the air flow direction, flowing to the left side and flowing upward in the tube 49a, the first partition of the upper header tank 47 is reached. The air flows into the space R4 on the upstream side in the air flow direction with respect to the portion 47a and on the left side with respect to the second partition portion 47b, and flows out to the outside through the outlet 47d.

  The upstream-side vehicle interior heat exchanger 32 is only larger in size than the downstream-side vehicle interior heat exchanger 31, and has the same structure as the downstream-side vehicle interior heat exchanger 31, so that the detailed description will be given. Omitted.

  The vehicle exterior heat exchanger 33 is disposed in the vicinity of the front end of the motor room in a motor room (corresponding to an engine room in an engine-driven vehicle) provided in the front part of the vehicle so that traveling wind can strike it. As shown in FIG. 4, the vehicle exterior heat exchanger 33 includes an upper header tank 57, a lower header tank 58, and a core 59. The core 59 is obtained by alternately arranging tubes 59a and fins 59b extending in the vertical direction in the left-right direction so that air for air conditioning passes between the tubes 59a.

  The upper end of the tube 59a is connected to and communicates with the upper header tank 57. The lower end of the tube 59a is connected to and communicates with the lower header tank 58.

  Inside the lower header tank 58, a partition portion 58a that partitions the inside of the lower header tank 58 in the left-right direction is provided. An inflow pipe 58b through which refrigerant flows is provided on the left side of the lower header tank 58, and an outflow pipe 58c through which refrigerant flows out is provided on the right side.

  Therefore, in the vehicle exterior heat exchanger 33, the refrigerant flowing from the inflow pipe 58b flows into the space T1 on the left side of the partition 58a of the lower header tank 58, and then passes through the tube 59a communicating with the space T1. Then, the gas flows into the upper header tank 57 and flows to the right, and then flows downward through the tube 59a. Then, after flowing into the space T2 on the right side of the partition 58a of the lower header tank 58, it flows out from the outflow pipe 58c.

  As shown in FIG. 1, a cooling fan 37 is provided in the vehicle. The cooling fan 37 is driven by a fan motor 38 and is configured to blow air to the exterior heat exchanger 33. The fan motor 38 is connected to the air conditioning control device 22 so as to be switched between ON and OFF and to control the rotation speed. Electric power is also supplied to the fan motor 38 from the traveling storage battery.

  The cooling fan 37 can also blow air to a radiator for cooling a traveling inverter or the like, for example, and can be operated other than when air conditioning is required.

  The 1st main refrigerant | coolant piping 40 connects the discharge port of the electric compressor 30, and the refrigerant | coolant inflow port of the downstream vehicle interior heat exchanger 31. As shown in FIG. The second main refrigerant pipe 41 connects the refrigerant outlet of the downstream-side vehicle interior heat exchanger 31 and the refrigerant inlet of the vehicle exterior heat exchanger 33. The third main refrigerant pipe 42 connects the refrigerant outlet of the vehicle exterior heat exchanger 33 and the refrigerant inlet of the upstream vehicle interior heat exchanger 32. The fourth main refrigerant pipe 43 connects the refrigerant outlet of the upstream side vehicle interior heat exchanger 32 and the inlet of the electric compressor 30.

  Further, the first branch refrigerant pipe 44 branches from the second main refrigerant pipe 41 and is connected to the third main refrigerant pipe 42. The second branch refrigerant pipe 45 branches from the second main refrigerant pipe 41 and is connected to the fourth main refrigerant pipe 43. The third branch refrigerant pipe 46 branches from the third main refrigerant pipe 42 and is connected to the fourth main refrigerant pipe 43.

  The accumulator 34 is disposed in the vicinity of the suction port of the electric compressor 30 in the middle of the fourth main refrigerant pipe 43.

  The heat pump device 20 includes a high-pressure side flow switching device 50, a low-pressure side flow switching device 51, a first expansion valve 52, a second expansion valve 53, a first check valve 54, and a second check valve 55. ing.

  The high-pressure side flow switching device 50 constitutes the flow switching device of the present invention and is an electric type three-way valve controlled by the air conditioning control device 22. The arrangement position of the high pressure side flow path switching device 50 is in the middle of the second main refrigerant pipe 41, and the first branch refrigerant pipe 44 is connected thereto.

  Although not shown, the high pressure side flow path switching device 50 has a built-in switching valve. By operating this switching valve, it is possible to change the flow of refrigerant and change the amount of refrigerant flowing into each pipe.

  The low-pressure side flow switching device 51 is also composed of an electric type three-way valve similar to the high-pressure side flow switching device 50 and is controlled by the air conditioning control device 22. The low-pressure side flow switching device 51 is provided in the middle of the fourth main refrigerant pipe 43 and is connected to the third branch refrigerant pipe 46.

  The first expansion valve 52 and the second expansion valve 53 are of an electric type, and are in an expanded state in which the flow path is throttled to expand the refrigerant and a non-expanded state in which the flow path is opened and the refrigerant is not expanded. Can be switched to. The first expansion valve 52 and the second expansion valve 53 are controlled by the air conditioning controller 22. In the expanded state, the opening degree is set according to the state of the air conditioning load.

  The first expansion valve 52 is disposed closer to the vehicle exterior heat exchanger 33 than the high-pressure channel switching device 50 of the second main refrigerant pipe 41. The second expansion valve 53 is disposed closer to the vehicle exterior heat exchanger 33 than the third branch refrigerant pipe 46 of the third main refrigerant pipe 42.

  The first check valve 54 is disposed in the third main refrigerant pipe 42, and the refrigerant flows from the vehicle exterior heat exchanger 33 side to the upstream vehicle interior heat exchanger 32 side of the third main refrigerant pipe 42. The refrigerant is allowed to flow, and the refrigerant is prevented from flowing in the reverse direction.

  The second check valve 55 is disposed in the second branch refrigerant pipe 45 and allows the refrigerant to flow from the main refrigerant pipe 43 side to the second main refrigerant pipe 41 side of the second branch refrigerant pipe 45. And it is comprised so that the flow of the refrigerant | coolant to a reverse direction may be blocked | prevented.

  Further, the vehicle interior air conditioning unit 21 includes a casing 60 that houses the downstream-side vehicle interior heat exchanger 31 and the upstream-side vehicle interior heat exchanger 32, an air heater 61 that is accommodated in the casing 60, and the interior of the casing 60 (the vehicle An air mix door (temperature control door) 62, an air mix door actuator 63 that drives the air mix door 62, a blow mode switching door 64, and a blower 65 are provided to switch the air flow direction in the indoor air conditioning unit 21). ing. The air mix door 62 constitutes a blowing amount changing means.

  The blower 65 is for selecting one of the air in the vehicle interior (inside air) and the air outside the vehicle interior (outside air) and blowing it into the casing 60 as air-conditioning air. The blower 65 includes a sirocco fan 65a and a blower motor 65b that rotationally drives the sirocco fan 65a. The blower motor 65b is connected to the air conditioning control device 22 so as to be switched between ON and OFF and to control the rotation speed. Power is also supplied to the blower motor 65b from the traveling storage battery.

  The casing 60 is disposed inside an instrument panel (not shown) in the vehicle interior. The casing 60 is formed with a defroster outlet 60a, a vent outlet 60b, and a heat outlet 60c. These air outlets 60a to 60c are opened and closed by the air outlet mode switching door 64, respectively. Although not shown, the blow mode switching door 64 is operated by an actuator connected to the air conditioning control device 22. Examples of the blowing mode include a defroster mode in which conditioned air flows to the defroster outlet 60a, a vent mode in which conditioned air flows to the vent outlet 60b, a heat mode in which conditioned air flows to the heat outlet 60c, a defroster outlet 60a, and a heat blower These include a differential / heat mode in which conditioned air flows to the outlet 60c, a bi-level mode in which conditioned air flows to the vent outlet 60b and the heat outlet 60c.

  The entire amount of the air-conditioning air introduced into the casing 60 passes through the upstream-side vehicle interior heat exchanger 32.

  Further, a bypass passage 60d is formed in the casing 60. The bypass passage 60d prevents the air that has passed through the upstream vehicle interior heat exchanger 32 from flowing to the downstream vehicle interior heat exchanger 31 side, bypasses the downstream vehicle interior heat exchanger 31, and downstream It is for flowing to.

  The air mix door 62 is accommodated in the casing 60 between the upstream side vehicle interior heat exchanger 32 and the downstream side vehicle interior heat exchanger 31. The air mix door 62 passes through the upstream vehicle interior heat exchanger 32 by changing the amount of air passing through the downstream vehicle interior heat exchanger 31 among the air that has passed through the upstream vehicle interior heat exchanger 32. This is for adjusting the temperature of the blown air by determining the mixing ratio of the air that has passed through and the air that has passed through the downstream side interior heat exchanger 31.

  The opening degree of the air mix door 62 passes through the opening degree that blocks the air flow to the downstream side interior heat exchanger 31 (the opening degree that fully opens the bypass passage 60d) and the upstream side interior heat exchanger 32. It can be switched to an arbitrary opening degree between the opening degree (the opening degree at which the bypass passage 60d is fully closed) through which the entire amount of air flows to the downstream side vehicle interior heat exchanger 31.

  The air that has passed through the downstream-side vehicle interior heat exchanger 31 and the air that has passed through the bypass passage 60d are mixed in a region downstream of the air mix door 62 inside the casing 60 to become conditioned air at a desired temperature.

  The air heater 61 is accommodated on the downstream side of the downstream-side vehicle interior heat exchanger 31 in the casing 60. The air heater 61 can be configured by a PTC heater using a PTC element that generates heat by flowing an electric current, for example. The air heater 61 is connected to the air-conditioning control device 22 so that the ON / OFF switching and the heat generation amount (power supply amount) are controlled. The air heater 61 is also supplied with power from the traveling storage battery.

  Further, the vehicle air conditioner 1 includes an outside air temperature sensor 70, a vehicle exterior heat exchanger temperature sensor 71, a high-pressure side refrigerant pressure detection sensor 72, an upstream vehicle interior heat exchanger temperature sensor 73, and a downstream vehicle interior. A heat exchanger temperature sensor 74, a blown air temperature sensor 75, and an upstream vehicle interior heat exchanger sensor (refrigerant pressure sensor, refrigerant temperature sensor) 77 are provided. These sensors 70 to 75 and 77 are connected to the air conditioning control device 22.

  The outside air temperature sensor 70 is arranged on the upstream side in the air flow direction with respect to the vehicle exterior heat exchanger 33, and detects the temperature of the external air (outside air temperature TG) before flowing into the vehicle exterior heat exchanger 33. belongs to. The vehicle exterior heat exchanger temperature sensor 71 is disposed on the downstream surface of the vehicle exterior heat exchanger 33 in the air flow direction, and detects the surface temperature of the vehicle exterior heat exchanger 33.

  The high-pressure side refrigerant pressure detection sensor 72 is disposed on the discharge port side of the electric compressor 30 in the first main refrigerant pipe 40, and the high-pressure side refrigerant pressure of the heat pump device 20, that is, the downstream-side vehicle interior heat exchanger 31. The pressure of the refrigerant flowing through the is detected.

  The upstream-side vehicle interior heat exchanger temperature sensor 73 is disposed downstream of the upstream-side vehicle interior heat exchanger 32 in the air flow direction, and detects the surface temperature of the upstream-side vehicle interior heat exchanger 32 to detect the upstream temperature. This is to obtain the temperature of the external air that has passed through the side vehicle interior heat exchanger 32.

  The downstream vehicle interior heat exchanger temperature sensor 74 is disposed downstream of the downstream vehicle interior heat exchanger 31 in the air flow direction, and detects the surface temperature of the downstream vehicle interior heat exchanger 31 to detect the downstream temperature. This is for obtaining the temperature of the external air that has passed through the side vehicle interior heat exchanger 31.

  The blown air temperature sensor 75 detects the temperature of the blown air blown from the casing 60, that is, the temperature of the conditioned air blown into the vehicle interior, and is disposed at a predetermined location in the vehicle compartment.

  The upstream side vehicle interior heat exchanger sensor 77 is for individually detecting the pressure and temperature of the refrigerant flowing through the upstream vehicle interior heat exchanger 32.

  Further, the air conditioner 1 is provided with a vehicle interior temperature sensor 76 for detecting the temperature (TR) in the vehicle interior, and this sensor 76 is also connected to the air conditioning controller 22.

  For example, the air conditioning control device 22 sets the operation mode of the heat pump device 20 based on information such as the temperature set by the occupant, the outside air temperature, the passenger compartment temperature, and the amount of solar radiation, and the air volume of the blower 65 (the rotational speed of the blower motor 65b). And the opening degree of the air mix door 62 are set, and the mode of the high-pressure side flow path switching device 50 is also set.

  Then, the heat pump device 20 is controlled so as to be in the set operation mode, and further, the blower 65 and the air mix door actuator 63 are controlled so as to become the set air volume and the set opening degree. And ROM, RAM, and the like.

  Moreover, the electric compressor 30 and the fan motor 38 are controlled according to the load of air conditioning, and the air heater 61 is also controlled as needed.

  The air conditioning control device 22 switches the operation mode of the heat pump device 20, the air volume of the blower 65, the opening degree of the air mix door 62, the switching of the blowing mode, and the electric compressor 30 in the main routine described later, as in the case of normal auto air conditioning control. The blower motor 65b is controlled. For example, the fan motor 38 is basically operated while the electric compressor 30 is operating, but even when the electric compressor 30 is in a stopped state, cooling of the traveling inverter and the like can be performed. Operates when necessary.

  There are four types of operation modes of the heat pump device 20: a heating start-up operation mode, a normal heating operation mode, a cooling operation mode, and a defrosting operation mode.

  The heating start-up operation mode shown in FIG. 5 is a refrigerant on the high-pressure side of the heat pump device 20 such as when the outside air temperature is lower than 0 ° C. (very low outside air) and the vehicle is left for a long time. This is an operation mode that is selected in a situation where the temperature is estimated to decrease until the temperature falls below the outside air temperature (predetermined low temperature). In the heating start-up operation mode, the downstream-side interior heat exchanger 31 and the upstream-side interior heat exchanger 32 function as heat radiators, and the exterior heat exchanger 33 functions as a heat absorber. In the figure, a broken line indicates a refrigerant pipe without a refrigerant flow.

  In this heating start-up operation mode, the high-pressure side flow path switching device 50 switches the flow path so that the refrigerant that has flowed out of the downstream-side vehicle interior heat exchanger 31 flows into the upstream-side vehicle interior heat exchanger 32. The low-pressure side flow switching device 51 switches the flow path so that the refrigerant that has flowed out of the vehicle exterior heat exchanger 33 flows into the accumulator 34. The first expansion valve 52 is in an expanded state, and the second expansion valve 53 is in a non-expanded state.

  In the heating start-up operation mode, the opening degree of the air mix door 62 of the vehicle interior air conditioning unit 21 is controlled so that the bypass passage 60d is fully opened. This is the heating start-up control. Therefore, in the heating start-up operation mode, the air that has passed through the upstream side vehicle interior heat exchanger 32 does not pass through the downstream side vehicle interior heat exchanger 31.

  It should be noted that some air may pass through the downstream side heat exchanger 31 due to a sealing problem at the periphery of the air mix door 62, but in this state as well, the opening degree of the air mix door 62 is determined by the bypass passage. It is assumed that the opening is at 60d.

  When the electric compressor 30 is operated in this state, the high-pressure refrigerant discharged from the electric compressor 30 flows through the first main refrigerant pipe 40 and flows into the downstream-side vehicle interior heat exchanger 31, and the downstream-side vehicle interior heat exchanger 31. Circulate. The refrigerant that has circulated through the downstream-side vehicle interior heat exchanger 31 flows into the high-pressure side flow switching device 50 from the second main refrigerant pipe 41. The refrigerant that has flowed into the high-pressure side flow switching device 50 flows through the first branch refrigerant pipe 44, flows into the upstream side vehicle interior heat exchanger 32, and circulates through the upstream side vehicle interior heat exchanger 32.

  The refrigerant that has circulated through the upstream side vehicle interior heat exchanger 32 flows from the fourth main refrigerant pipe 43 into the second main refrigerant pipe 41 through the second branch refrigerant pipe 45. The refrigerant that has flowed into the second main refrigerant pipe 41 expands by passing through the first expansion valve 52 and flows into the vehicle exterior heat exchanger 33. The refrigerant flowing into the exterior heat exchanger 33 absorbs heat from the outside air, passes through the third main refrigerant pipe 42 and the third branch refrigerant pipe 46 in order, and is sucked into the electric compressor 30 through the accumulator 34.

  In this heating start-up operation mode, the refrigerant discharged from the electric compressor 30 circulates in the downstream-side vehicle interior heat exchanger 31, but does not allow air-conditioning air to flow through the downstream-side vehicle interior heat exchanger 31. Since the opening degree of the mix door 62 is set, heat exchange between the refrigerant circulating in the downstream-side vehicle interior heat exchanger 31 and the external air is hardly performed. Therefore, the temperature and pressure increase of the refrigerant on the high pressure side of the heat pump device 20 is accelerated.

  In the normal heating operation mode shown in FIG. 6, for example, when the outside air temperature is lower than 0 ° C. (very low outside air) and the refrigerant temperature on the high pressure side of the heat pump device 20 is higher than the outside air temperature, the heating is performed. This operation mode is selected in a situation where it is estimated that the startup operation mode is unnecessary.

  In the normal heating operation mode, the downstream-side interior heat exchanger 31 and the upstream-side interior heat exchanger 32 serve as radiators, and the exterior heat exchanger 33 acts as a heat absorber.

  Further, in the normal heating operation mode, the opening degree of the air mix door 62 of the vehicle interior air conditioning unit 21 is controlled so as to be the opening degree obtained from the set temperature of the occupant. This is normal heating control. Therefore, in the normal heating operation mode, generally, the air that has passed through the upstream vehicle interior heat exchanger 32 passes through the downstream vehicle interior heat exchanger 31, so that the downstream side as compared with the heating start-up operation mode. The amount of air passing through the vehicle interior heat exchanger 31 increases.

  That is, the high pressure side flow path switching device 50 and the low pressure side flow path switching device 51 are made the same as in the heating operation mode. The first expansion valve 52 is in an expanded state, and the second expansion valve 53 is in a non-expanded state.

  When the electric compressor 30 is operated in this state, the high-pressure refrigerant discharged from the electric compressor 30 flows in the same manner as in the heating operation mode, so that the high temperature in the downstream side vehicle interior heat exchanger 31 and the upstream side vehicle interior heat exchanger 32 is high. The refrigerant in the state will flow in. The air for air conditioning is heated by both the downstream-side vehicle interior heat exchanger 31 and the upstream-side vehicle interior heat exchanger 32, and thus a high heating capacity is obtained.

  The cooling operation mode shown in FIG. 7 is an operation mode selected when the outside air temperature is higher than 25 ° C., for example. In the cooling operation mode, the downstream side interior heat exchanger 31 serves as a radiator, the upstream side interior heat exchanger 32 serves as a heat absorber, and the exterior heat exchanger 33 serves as a radiator.

  That is, the high-pressure side flow path switching device 50 causes the refrigerant that has flowed out of the downstream side interior heat exchanger 31 to flow toward the first expansion valve 52 side so as not to flow into the inlet of the upstream side interior heat exchanger 32. Switch the flow path to. Further, the low-pressure side flow path switching device 51 switches the flow path so that the refrigerant that has flowed out of the upstream side passenger compartment heat exchanger 32 flows into the accumulator 34. The first expansion valve 52 is in a non-expanded state, and the second expansion valve 53 is in an expanded state.

  Further, in the cooling operation mode, the opening degree of the air mix door 62 of the vehicle interior air conditioning unit 21 is controlled so as to be the opening degree obtained from the set temperature of the occupant.

  When the electric compressor 30 is operated in this state, the high-pressure refrigerant discharged from the electric compressor 30 flows through the first main refrigerant pipe 40 and flows into the downstream-side vehicle interior heat exchanger 31, and the downstream-side vehicle interior heat exchanger 31. Circulate. The refrigerant that has circulated through the downstream-side vehicle interior heat exchanger 31 flows into the vehicle exterior heat exchanger 33 without being expanded through the second main refrigerant pipe 41. The refrigerant flowing into the vehicle exterior heat exchanger 33 dissipates heat, passes through the third main refrigerant pipe 42 and passes through the second expansion valve 53, expands, and flows into the upstream vehicle interior heat exchanger 32. The refrigerant flowing into the upstream side vehicle interior heat exchanger 32 circulates through the upstream side vehicle interior heat exchanger 32 and absorbs heat from the air for air conditioning. The refrigerant that has circulated through the upstream-side vehicle interior heat exchanger 32 is sucked into the electric compressor 30 through the fourth main refrigerant pipe 43 and the accumulator 34.

  The amount of air passing through the downstream-side vehicle interior heat exchanger 31 and the amount of air passing through the upstream-side vehicle interior heat exchanger 32 are changed depending on the opening degree of the air mix door 62 to generate conditioned air at a desired temperature. .

  The defrosting operation mode shown in FIG. 8 is an operation mode selected when frost adheres to the vehicle exterior heat exchanger 33. In the defrosting operation mode, the downstream side vehicle interior heat exchanger 31, the upstream side vehicle interior heat exchanger 32, and the vehicle exterior heat exchanger 33 are caused to act as radiators.

  That is, the high-pressure side flow path switching device 50 switches the flow path so that the refrigerant flowing through the downstream side interior heat exchanger 31 flows to the upstream side interior heat exchanger 32 and the exterior heat exchanger 33. The low-pressure side flow switching device 51 switches the flow path so that the refrigerant that has flowed out of the vehicle exterior heat exchanger 33 flows into the accumulator 34. The first expansion valve 52 is in an expanded state, and the second expansion valve 53 is in a non-expanded state.

  When the electric compressor 30 is operated in this state, the high-pressure refrigerant discharged from the electric compressor 30 flows through the first main refrigerant pipe 40 and flows into the downstream-side vehicle interior heat exchanger 31, and the downstream-side vehicle interior heat exchanger 31. Circulate. The refrigerant that has circulated through the downstream-side vehicle interior heat exchanger 31 flows into the high-pressure side flow switching device 50 from the second main refrigerant pipe 41. The refrigerant that has flowed out of the high-pressure side flow switching device 50 flows through the first branch refrigerant pipe 44, flows into the upstream side vehicle interior heat exchanger 32, and circulates through the upstream side vehicle interior heat exchanger 32. The refrigerant that has circulated through the upstream side vehicle interior heat exchanger 32 flows from the fourth main refrigerant pipe 43 into the second main refrigerant pipe 41 through the second branch refrigerant pipe 45. Further, the other refrigerant that has flowed out of the high-pressure side flow path switching device 50 flows into the second main refrigerant pipe 41 without circulating through the upstream side vehicle interior heat exchanger 32.

  The refrigerant merged in the second main refrigerant pipe 41 flows into the vehicle exterior heat exchanger 33. The refrigerant flowing into the exterior heat exchanger 33 absorbs heat from the outside air, and then passes through the third main refrigerant pipe 42 and the third branch refrigerant pipe 46 in order, and is sucked into the electric compressor 30 through the accumulator 34.

  In any of the heating start-up operation mode, the normal heating operation mode, the cooling operation mode, and the defrosting operation mode, the downstream-side vehicle interior heat exchanger 31 functions as a radiator.

  In any of the operation modes, the refrigerant pipe into which the refrigerant flows into the vehicle exterior heat exchanger 33 is the second main refrigerant pipe 41, and the refrigerant from which the refrigerant flows out of the vehicle exterior heat exchanger 33. The pipe is a third main refrigerant pipe 42. Therefore, in the vehicle exterior heat exchanger 33, the refrigerant always flows in the same direction, and when compared with the heat pump device configured so that the refrigerant also flows in the reverse direction, only the flow dividing property in the same direction is obtained for the refrigerant. The outside heat exchanger 33 may be considered, and the heat exchange performance of the outside heat exchanger 33 can be improved relatively easily.

  In any operation mode, the refrigerant is circulated through the tube 49a on the downstream side in the air flow direction of the downstream side interior heat exchanger 31 and then circulated through the tube 49a on the upstream side before being discharged. You can Thereby, the downstream side vehicle interior heat exchanger 31 can be arrange | positioned so that it may become a counterflow arrangement | positioning which makes the flow of the refrigerant | coolant of the downstream vehicle interior heat exchanger 31 oppose the flow direction of external air. In any of the operation modes, after the refrigerant is circulated through a tube (not shown) on the downstream side in the air flow direction of the upstream side vehicle interior heat exchanger 32, the upstream side tube (not shown) is similarly shown. 1), the refrigerant can be discharged after being circulated, so that the upstream-side vehicle interior heat exchanger 32 can also be arranged in a counterflow manner.

  By arranging the downstream-side vehicle interior heat exchanger 31 in a counter-flow arrangement, a higher temperature refrigerant flows in the downstream side in the air flow direction in the downstream-side vehicle interior heat exchanger 31 particularly in the normal heating mode. Heating can be performed and the heating performance is improved.

  Further, by arranging the upstream side vehicle interior heat exchanger 32 in a counterflow arrangement, the refrigerant having a lower temperature flows in the downstream side in the air flow direction in the upstream vehicle interior heat exchanger 32, particularly in the cooling mode. Cooling can be performed well and the cooling performance is improved.

  As shown in FIG. 2, the air conditioning control device 22 includes a frosting determination unit 22 a that determines whether or not frost is attached to the exterior heat exchanger 33. The frosting determination unit 22a subtracts the surface temperature of the vehicle exterior heat exchanger 33 detected by the vehicle exterior heat exchanger temperature sensor 71 from the outdoor air temperature (TG) detected by the outdoor air temperature sensor 70, and the value is obtained. For example, when the value is larger than 20 (° C.), it is determined that frost formation has occurred. That is, if frost is attached to the vehicle exterior heat exchanger 33, the refrigerant cannot be absorbed in the vehicle exterior heat exchanger 33, and the frost determination is performed using the fact that the refrigerant temperature does not rise. Therefore, the value of 20 described above may be a value that can determine whether or not the vehicle exterior heat exchanger 33 is frosted, and may be another value.

  Next, a control procedure by the air conditioning control device 22 will be described based on FIGS. 9 and 10. FIG. 9 shows the main routine. In step SA1 after the start, the outside air temperature (TG) detected by the outside air temperature sensor 70 is read. In step SA2 following step SA1, it is determined whether the outside air temperature (TG) is lower than 0 ° C. or higher than 0 ° C.

  If it is determined in step SA2 that the outside air temperature (TG) is lower than 0 ° C., the process proceeds to step SA3, the heating subroutine control shown in FIG. 10 is performed, and the process proceeds to the end of the main routine. In the heating subroutine control, the heat mode is mainly selected as the blowing mode of the vehicle interior air conditioning unit 21. Further, the air mix door 62 is operated so that the temperature of the blown air becomes the target temperature.

  If it is determined in step SA2 that the outside air temperature (TG) is 0 ° C. or higher, the process proceeds to step SA4, the heat pump device 20 is switched to the cooling operation mode, and the process proceeds to the end of the main routine.

  Moreover, when frost has adhered to the exterior heat exchanger 33, the defrosting operation mode is selected.

  The heating subroutine control shown in the flowchart shown in FIG. 10 will be described. In step SB1 after the start, the outside air temperature (TG) detected by the outside air temperature sensor 70 is read.

  In step SB2 following step SB1, it is determined whether or not the outside air temperature (TG) is higher than −10 ° C. When it is determined as NO in step SB2 and the outside air temperature (TG) is −10 ° C. or lower, it is determined that the vehicle is in the cold start state, and the process proceeds to step SB3 to set the operation mode to the heating start-up operation mode. In addition, since the value of -10 should just be a value which can determine whether the refrigerant | coolant temperature of the high pressure side of the heat pump apparatus 20 is a low state, you may use another value.

  In the heating start-up operation mode, since the air mix door 62 fully opens the bypass passage 60d, the amount of air passing through the downstream side vehicle interior heat exchanger 31 is smaller than that in the normal heating operation mode.

  Thereafter, the process proceeds to step SB4, and the output value of the high-pressure side refrigerant pressure detection sensor 72, that is, the high-pressure side refrigerant pressure (P) of the heat pump device 20 is read. After reading the refrigerant pressure (P), the process proceeds to step SB5, and it is determined whether or not the refrigerant pressure (P) is higher than 1.0 MPa. If NO is determined in step SB5 and the refrigerant pressure (P) is 1.0 MPa or less, the process returns to step SB4, and the high-pressure side refrigerant pressure (P) of the heat pump device 20 is read again, and the same applies in step SB5. Make a good judgment. That is, it is estimated that the refrigerant temperature on the high-pressure side of the heat pump device 20 is low until the high-pressure side refrigerant pressure becomes higher than 1.0 MPa, and the heating start-up operation mode is continued.

  In addition, you may change 1.0 MPa which is the said determination pressure value according to external temperature. For example, the lower the outside air temperature, the slower the increase rate of the refrigerant temperature on the high pressure side of the heat pump device 20, so the determination pressure value is made smaller.

  When it is determined as YES in Step SB5 and the refrigerant pressure on the high pressure side of the heat pump device 20 becomes higher than 1 MPa, it is estimated that the refrigerant temperature is also high, and the heating start-up operation is considered unnecessary. . In this case, it progresses to step SB6 and switches to normal heating operation mode.

  If YES in step SB2 and the outside air temperature (TG) is higher than −10 ° C., it can be estimated that the refrigerant temperature on the high-pressure side of the heat pump device 20 is high and heating start-up operation is not necessary, so step SB6 Then, the operation mode of the heat pump device 20 is set to the normal heating operation mode.

  Therefore, the air conditioning control device 22 estimates whether or not the refrigerant temperature on the high pressure side of the heat pump device 20 is equal to or lower than a predetermined low temperature in steps SB2 and SB5. And if it estimates that the refrigerant | coolant temperature of the high pressure side of the heat pump apparatus 20 is below predetermined low temperature (NO in step SB4, NO in step SB5), it will drive | operate in heating start-up operation mode. On the other hand, if it is estimated that the refrigerant temperature on the high pressure side of the heat pump device 20 is higher than a predetermined low temperature (YES in step SB2, YES in step SB5), the normal heating operation mode is set.

  That is, the air-conditioning control device 22 is more downstream when it is estimated that the refrigerant temperature on the high-pressure side of the heat pump device 20 is equal to or lower than the predetermined low temperature than when it is estimated that the refrigerant temperature is higher than the predetermined low temperature. The air mix door 62 is controlled so that the amount of air blown to the vehicle interior heat exchanger 31 is reduced.

  When the frost determination unit 22a determines that frost is attached to the exterior heat exchanger 33 during the heating operation mode, the operation mode of the heat pump device 20 is switched to the defrost operation mode. When defrosting is complete, switch to heating operation mode.

  As described above, according to the first embodiment, the outside air temperature is low, for example, in the winter, and the refrigerant on the high-pressure side of the heat pump device 20 is cooled to near the outside air temperature after being left for a long time. Then, it is estimated that the refrigerant temperature on the high pressure side is equal to or lower than a predetermined low temperature. In this case, since the bypass passage 60d is fully opened by the air mix door 62, the amount of air blown to the downstream side vehicle interior heat exchanger 31 is smaller than that in the normal heating operation mode. As a result, it is possible to reduce the amount of heat exchanged between the refrigerant discharged from the electric compressor 30 and external air when flowing through the downstream-side vehicle interior heat exchanger 31. Therefore, since the temperature fall of the refrigerant | coolant of the high voltage | pressure side of the heat pump apparatus 20 is suppressed, the raise of a refrigerant | coolant pressure and temperature becomes quick, the start-up of heating becomes quick, and a passenger | crew's comfort can be improved.

  In addition, since the air mix door 62 is used to switch the air flow rate to the downstream-side vehicle interior heat exchanger 31, the air flow rate can be easily and reliably switched.

  In addition, when it is determined that the refrigerant pressure has become higher than the predetermined pressure after the heating start-up operation mode, the heat pump device 20 and the vehicle interior air conditioning unit 21 are switched to the normal heating mode, and therefore based on the actual refrigerant temperature. Can be switched to normal heating. Thereby, normal heating can be performed at an appropriate timing after the start of heating.

  Further, the outside air temperature (TG), which is the temperature outside the passenger compartment, is related to the high-pressure side refrigerant temperature of the heat pump device 20, and if the outside air temperature (TG) is low, the high-pressure side refrigerant temperature of the heat pump device 20 is also low. It is thought that. In the present embodiment, since the outside air temperature (TG) is detected and the refrigerant temperature on the high pressure side of the heat pump apparatus 20 is estimated, the estimation result becomes accurate and appropriate control can be performed.

  In the above embodiment, the refrigerant pressure (P) on the high-pressure side is read after the heating start-up operation mode in step SB4, and then the heating start-up operation should be continued in step SB5, or it is finished and the normal heating operation is finished. However, the present invention is not limited to this. For example, after starting the heating start-up operation mode, the refrigerant temperature detected by the upstream vehicle interior heat exchanger sensor 77 in step SB4 is predetermined. If it is determined that the temperature is higher than the temperature, the heat pump device 20 and the vehicle interior air conditioning unit 21 may be switched to the normal heating operation mode (normal heating control). In this case, since the actual refrigerant temperature can be detected and switched to normal heating based on the detected temperature, normal heating can be performed at an appropriate timing after the start-up of heating is completed, and passenger comfort can be improved.

  Further, the air temperature after passing through the upstream side vehicle interior heat exchanger 32 is detected by the upstream side vehicle interior heat exchanger temperature sensor 73, and after starting the heating start-up control, the upstream side vehicle interior heat exchanger temperature sensor is detected. When it is determined that the air temperature detected at 73 is higher than the predetermined temperature, the heat pump device 20 and the vehicle interior air conditioning unit 21 may be switched to the normal heating operation mode.

  In this case, the heating start-up operation mode can be switched to the normal heating operation mode based on the air temperature after passing through the upstream side vehicle interior heat exchanger 32. Therefore, normal heating can be performed at an appropriate timing, and passenger comfort can be further improved.

  The temperature used for the determination may be changed according to the outside air temperature. For example, the lower the outside air temperature, the slower the rising speed of the refrigerant temperature on the high pressure side, so the temperature used for the determination is lowered.

(Embodiment 2)
FIG. 11: is a flowchart which shows the heating subroutine control procedure concerning Embodiment 2 of this invention. The second embodiment is different from the first embodiment only in the heating subroutine control procedure, and the other parts are the same as those in the first embodiment. Hereinafter, a different part from Embodiment 1 is demonstrated in detail.

  In step SC1 of the flowchart shown in FIG. 11, the outside air temperature (TG) detected by the outside air temperature sensor 70 is read.

  In step SC2 following step SC1, it is determined whether or not the outside air temperature (TG) is higher than −10 ° C. If it is determined NO in step SC2 and the outside air temperature (TG) is −10 ° C. or lower, it is determined that the vehicle is in a cold start state, and the process proceeds to step SC3 to set the operation mode to the heating start-up operation mode.

  Thereafter, the process proceeds to step SC4, where the timer is set to 0 and time counting is started. The elapsed time from the start of the operation in the heating start-up operation mode can be obtained by the timer.

  Thereafter, the process proceeds to step SC5, and it is determined whether or not the timer has exceeded 60 seconds, that is, whether or not a predetermined time has elapsed since the start of the operation in the heating start-up operation mode. If it is determined as NO in step SC5 and the timer has not passed 60 seconds, the determination in step SC5 is performed once again and waits until 60 seconds have passed.

  If it is determined as YES in step SC5 and the timer has passed 60 seconds, the process proceeds to step SC6, and the mode is switched to the normal heating operation mode.

  That is, in the second embodiment, the heat pump device 20 and the vehicle interior air conditioning unit 21 are switched to the normal heating operation mode after a predetermined time has elapsed since the start of the operation in the heating start-up operation mode. Steps for estimating whether or not the refrigerant temperature on the high pressure side of the heat pump device 20 is equal to or lower than a predetermined low temperature are steps SC2 and SC5.

  Therefore, according to the second embodiment, as in the first embodiment, the bypass passage 60d is fully opened by the air mix door 62 in a situation where the refrigerant on the high pressure side of the heat pump device 20 is cooled to near the outside air temperature. Therefore, the amount of air blown to the downstream side vehicle interior heat exchanger 31 is smaller than that in the normal heating operation mode. Thereby, since the temperature fall of a refrigerant | coolant is suppressed, the raise of the refrigerant | coolant pressure and temperature of the high voltage | pressure side of the heat pump apparatus 20 becomes quick, the start-up of heating becomes quick, and a passenger | crew's comfort can be improved.

  Moreover, since it switched to the normal heating operation mode based on the elapsed time after starting the operation in the heating start-up operation mode, normal heating can be performed at an appropriate timing while performing simple control.

  Further, the time (predetermined time) between the start of the operation in the heating start-up operation mode and the switching to the normal heating operation mode may be changed according to the outside air temperature. Specifically, the lower the outside air temperature, the longer the predetermined time. When the outside air temperature is low in the extremely cold season, it may be possible to lengthen the time required to start up the heating, but in such a case, after starting the start-up control of the heating and switching to the normal heating operation By lengthening the time, normal heating can be performed at an appropriate timing.

  Further, the time (predetermined time) between the start of the operation in the heating start-up operation mode and the switching to the normal heating operation mode may be changed according to the refrigerant pressure on the high pressure side. Specifically, the lower the refrigerant pressure on the high pressure side, the longer the predetermined time. When the outside air temperature is low in the extremely cold season, the refrigerant pressure on the high pressure side is low, and the time required to start up the heating may be prolonged.In such a case, the start-up control of the heating is started. By increasing the time between switching to the normal heating operation after that, normal heating can be performed at an appropriate timing.

(Embodiment 3)
FIG. 12 is a flowchart showing a heating subroutine control procedure according to the third embodiment of the present invention. The third embodiment is different from the first embodiment only in the heating subroutine control procedure, and the other parts are the same as those in the first embodiment. Hereinafter, a different part from Embodiment 1 is demonstrated in detail.

  In step SD1 of the flowchart shown in FIG. 12, the outside temperature (TG) detected by the outside temperature sensor 70 is read.

  In step SD2 following step SD1, it is determined whether or not the outside air temperature (TG) is higher than −10 ° C. If it is determined as NO in step SD2 and the outside air temperature (TG) is −10 ° C. or lower, it is determined that the vehicle is in a cold start state, and the process proceeds to step SD3 to set the operation mode to the heating start-up operation mode.

  Then, it progresses to step SD4 and the output value of the high pressure side refrigerant | coolant pressure detection sensor 72, ie, the high pressure side refrigerant | coolant pressure (P) of the heat pump apparatus 20, is read. After reading the refrigerant pressure (P), the process proceeds to step SD5 to determine whether or not the refrigerant pressure (P) is higher than 0.5 MPa. If NO in step SD5 and the refrigerant pressure (P) is 0.5 MPa or less, the process returns to step SD4, and the refrigerant pressure (P) on the high pressure side of the heat pump device 20 is read again, and the same applies in step SD5. Make a good judgment. During this time, the heating start-up operation mode is continued.

  When YES is determined in step SD5 and the refrigerant pressure on the high pressure side becomes higher than 0.5 MPa, it can be estimated that the temperature of the refrigerant is increasing. In this case, the process proceeds to step SD6, and the air mix door 62 is set in the 1/2 open state. That is, the air that has passed through the upstream-side vehicle interior heat exchanger 32 is also heated by the downstream-side vehicle interior heat exchanger 31 by flowing through both the downstream-side vehicle interior heat exchanger 31 and the bypass passage 60d. The air mix door 62 may be in a 1/3 open state or in a 2/3 open state.

  Then, it progresses to step SD7 and the refrigerant | coolant pressure (P) of the high pressure side of the heat pump apparatus 20 is read. After reading the refrigerant pressure (P), the process proceeds to step SD8 to determine whether or not the refrigerant pressure (P) is higher than 1.0 MPa. If it is determined NO in step SD8 and the refrigerant pressure (P) is 1.0 MPa or less, the process returns to step SD7, the refrigerant pressure (P) on the high pressure side of the heat pump device 20 is read again, and the same in step SD8. Make a good judgment. During this time, the heating start-up operation mode is continued.

  In addition, you may change 1.0 MPa which is the said determination pressure value according to external temperature. For example, the lower the outside air temperature, the slower the increase rate of the refrigerant temperature on the high pressure side, so the determination pressure value is made smaller.

  Further, the determination pressure value in step SD5 (0.5 MPa) may be changed in accordance with the change of the determination pressure value 1.0 MPa.

  When it is determined as YES in Step SD8 and the refrigerant pressure on the high pressure side becomes higher than 1.0 MPa, the process proceeds to Step SD9 to switch to the normal heating operation mode. Thereby, the ventilation volume to the downstream side vehicle interior heat exchanger 31 increases. When the amount of blown air to the downstream-side vehicle interior heat exchanger 31 increases, the refrigerant pressure on the high-pressure side may decrease.

  In order to cope with this, in step SD10, it is determined again whether or not the refrigerant pressure (P) on the high pressure side of the heat pump device 20 is higher than 0.5 MPa.

  When NO is determined in step SD10 and the refrigerant pressure (P) on the high pressure side has decreased to 0.5 MPa or less, the process returns to step SD6 and the air mix door 62 is halved to the downstream side. The air flow rate to the vehicle interior heat exchanger 31 is reduced. Then, it waits for the refrigerant pressure on the high pressure side to rise through steps SD7 and SD8.

  If it is determined as YES in step SD10 and the high-pressure side pressure (P) is higher than 0.5 MPa, the process proceeds to the end.

  Therefore, according to the third embodiment, as in the first embodiment, the bypass passage 60d is fully opened by the air mix door 62 in a situation where the refrigerant on the high pressure side of the heat pump device 20 is cooled to near the outside air temperature. Therefore, the amount of air blown to the downstream side vehicle interior heat exchanger 31 is smaller than that in the normal heating operation mode. Thereby, since the temperature fall of a refrigerant | coolant is suppressed, the raise of the refrigerant | coolant pressure and temperature of the high voltage | pressure side of the heat pump apparatus 20 becomes quick, the start-up of heating becomes quick, and a passenger | crew's comfort can be improved.

  Moreover, although the said Embodiment 1-3 demonstrated the case where the vehicle air conditioner 1 was mounted in an electric vehicle, it is not restricted to this, For example, the vehicle air conditioner 1 is added to the hybrid vehicle provided with the engine and the motor for driving | running | working. It is also possible to install.

  The air mix door 62 may be plate-shaped or film-shaped, and is not particularly limited.

  Moreover, although the said embodiment demonstrated the case where there exist two vehicle interior heat exchangers which become a heat radiator, the downstream vehicle interior heat exchanger 31 and the upstream vehicle interior heat exchanger 32, it is not restricted to this, The present invention can also be applied to the case where there is one vehicle interior heat exchanger serving as a radiator (the air conditioner disclosed in Patent Document 1). That is, when it is estimated that the refrigerant temperature on the high-pressure side of the heat pump device 20 is equal to or lower than a predetermined low temperature, the amount of air blown to the vehicle interior heat exchanger that acts as a radiator in both the heating operation mode and the cooling operation mode In addition, the air mix door 62 is controlled so as to be smaller than the case where it is estimated that the temperature is higher than the predetermined low temperature.

  Also in this case, the same effects as those of the above embodiment can be achieved.

  In estimating whether the refrigerant temperature on the high-pressure side of the heat pump device 20 is equal to or lower than a predetermined low temperature, it may be estimated from the output value of the temperature sensor that detects the refrigerant temperature on the high-pressure side. The refrigerant pressure on the high pressure side may be detected and estimated, or may be estimated based on the elapsed time from the start of heating, and the estimation method is not particularly limited.

  Moreover, in the said embodiment, it is estimated whether the refrigerant | coolant temperature of the high pressure side of the heat pump apparatus 20 is below a predetermined low temperature, and when it is estimated that it is below a predetermined low temperature, heating start-up control is performed. However, the present invention is not limited to this. For example, at the start of heating, heating start-up control may be performed regardless of the refrigerant temperature on the high-pressure side, and thereafter, switching to the normal heating operation may be performed. The timing for switching to the normal heating operation may be, for example, a timing after a predetermined time has elapsed since the start of heating.

  As described above, the vehicle air conditioner according to the present invention can be mounted on, for example, an electric vehicle or a hybrid vehicle.

DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 20 Heat pump apparatus 21 Car interior air conditioning unit 22 Air conditioning control apparatus 22a Frosting judgment part 30 Electric compressor (compressor)
31 Downstream passenger compartment heat exchanger (first passenger compartment heat exchanger)
32 Upstream vehicle interior heat exchanger (second vehicle interior heat exchanger)
33 Outside heat exchangers 40 to 43 First to fourth main refrigerant pipes 44 to 46 First to third branch refrigerant pipes 50 High-pressure side flow path switching device (flow path switching device)
61 Air heater 62 Air mix door (temperature control door)
65 Blower 70 Outside Air Temperature Sensor 72 High Pressure Side Refrigerant Pressure Detection Sensor 73 Upstream Car Interior Heat Exchanger Temperature Sensor 74 Downstream Car Interior Heat Exchanger Temperature Sensor 77 Upstream Car Interior Heat Exchanger Sensor (Refrigerant Pressure Sensor, Refrigerant Temperature Sensor )

Claims (12)

A heat pump device including a compressor that compresses the refrigerant, a vehicle interior heat exchanger disposed in the vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior;
A vehicle interior air conditioning unit configured to house the vehicle interior heat exchanger and to have a blower that blows air for air conditioning in the vehicle interior heat exchanger and to generate conditioned air and supply the conditioned air to the vehicle interior; A vehicle air conditioner comprising:
An air flow rate changing means for changing the air flow rate to the vehicle interior heat exchanger;
An air conditioning control device for controlling the air flow rate changing means,
The air conditioning control device performs heating start-up control for controlling the air flow rate changing means at the start of heating so that the air flow rate to the vehicle interior heat exchanger is smaller than when a predetermined time has elapsed after the start of heating. An air conditioner for a vehicle that is configured to perform. A heat pump device including a compressor that compresses the refrigerant, a vehicle interior heat exchanger disposed in the vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior;
A vehicle interior air conditioning unit configured to house the vehicle interior heat exchanger and to have a blower that blows air for air conditioning in the vehicle interior heat exchanger and to generate conditioned air and supply the conditioned air to the vehicle interior; A vehicle air conditioner comprising:
An air flow rate changing means for changing the air flow rate to the vehicle interior heat exchanger;
An air conditioning control device for controlling the air flow rate changing means,
The air conditioning control device estimates whether or not the refrigerant temperature on the high pressure side of the heat pump device is equal to or lower than a predetermined low temperature. It is configured to perform heating start-up control for controlling the air flow rate changing means so that the air flow rate to the vehicle interior heat exchanger is smaller than that estimated to be high. A vehicle air conditioner. A heat pump device including a compressor for compressing a refrigerant, a first and second vehicle interior heat exchangers disposed in a vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior; ,
The first vehicle interior heat exchanger and the second vehicle interior heat exchanger are accommodated, and the air conditioner air is blown to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger. A vehicle interior air conditioning unit configured to generate and supply air to the vehicle interior;
A vehicle air conditioner comprising the heat pump device and an air conditioning control device for controlling the vehicle interior air conditioning unit,
The vehicle interior air conditioning unit includes an air flow rate changing means for changing the air flow rate to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger, and the air flow rate changing means is controlled by the air conditioning control device. And
The heat pump device is set to a heating operation mode in which the air conditioning control device uses the first vehicle interior heat exchanger and the second vehicle interior heat exchanger as radiators and the vehicle exterior heat exchanger functions as a heat absorber. Configured to
The air conditioning control device starts up the heating to control the air flow rate changing means so that the air flow rate to the first vehicle interior heat exchanger is smaller at the start of heating than when a predetermined time has elapsed after the start of heating. A vehicle air conditioner configured to perform control. A heat pump device including a compressor for compressing a refrigerant, a first and second vehicle interior heat exchangers disposed in a vehicle interior, and a vehicle exterior heat exchanger disposed outside the vehicle interior; ,
The first vehicle interior heat exchanger and the second vehicle interior heat exchanger are accommodated, and the air conditioner air is blown to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger. A vehicle interior air conditioning unit configured to generate and supply air to the vehicle interior;
A vehicle air conditioner comprising the heat pump device and an air conditioning control device for controlling the vehicle interior air conditioning unit,
The vehicle interior air conditioning unit includes an air flow rate changing means for changing the air flow rate to the first vehicle interior heat exchanger and the second vehicle interior heat exchanger, and the air flow rate changing means is controlled by the air conditioning control device. And
The heat pump device is set to a heating operation mode in which the air conditioning control device uses the first vehicle interior heat exchanger and the second vehicle interior heat exchanger as radiators and the vehicle exterior heat exchanger functions as a heat absorber. Configured to
The air conditioning control device estimates whether or not the refrigerant temperature on the high pressure side of the heat pump device is equal to or lower than a predetermined low temperature. It is configured to perform heating start-up control for controlling the air flow rate changing means so that the air flow rate to the first vehicle interior heat exchanger is smaller than that estimated to be high. A vehicle air conditioner. In the vehicle air conditioner according to any one of claims 1 to 4,
The vehicular air conditioner is a door for switching an air flow direction inside the vehicle interior air conditioning unit. In the vehicle air conditioner according to any one of claims 1 to 5,
It has an outside temperature sensor that detects the temperature outside the passenger compartment,
When the air temperature outside the passenger compartment is lower than a predetermined temperature based on the air temperature outside the passenger compartment detected by the outside air temperature sensor, the air conditioning control device determines that the refrigerant temperature on the high-pressure side of the heat pump device is lower than a predetermined low temperature. It is comprised so that it may be estimated below, The vehicle air conditioner characterized by the above-mentioned. In the vehicle air conditioner according to any one of claims 1 to 5,
A refrigerant temperature sensor for detecting the refrigerant temperature;
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the refrigerant temperature detected by the refrigerant temperature sensor has become higher than a predetermined temperature after heating start-up control. It is comprised as follows. The vehicle air conditioner characterized by the above-mentioned. In the vehicle air conditioner according to any one of claims 1 to 5,
A refrigerant pressure detection sensor for detecting the refrigerant pressure;
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the refrigerant pressure detected by the refrigerant pressure sensor has become higher than a predetermined pressure after heating start-up control. It is comprised as follows. The vehicle air conditioner characterized by the above-mentioned. In the vehicle air conditioner according to any one of claims 1 to 5,
It has an air temperature sensor that detects the air temperature after passing through the vehicle interior heat exchanger,
The air conditioning control device switches the heat pump device and the vehicle interior air conditioning unit to normal heating control when it is determined that the air temperature detected by the air temperature sensor has become higher than a predetermined temperature after heating start-up control. It is comprised as follows. The vehicle air conditioner characterized by the above-mentioned. In the vehicle air conditioner according to any one of claims 1 to 5,
The air-conditioning control device is configured to switch the heat pump device and the vehicle interior air-conditioning unit to normal heating control after a predetermined time has elapsed since the start of heating start-up control. . The vehicle air conditioner according to claim 10,
The vehicle air conditioner is configured to change a time between the start of heating start-up control and switching to normal heating control in accordance with the temperature outside the passenger compartment. The vehicle air conditioner according to claim 10,
The vehicle air conditioner is configured to change the time between the start of heating start-up control and switching to normal heating control in accordance with the refrigerant pressure on the high pressure side. .

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