JPH10264646A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate formation of a target blow temperature determined based on inner air temperature, outer air temperature, etc., by optimizing selecting conditions for a dehumidifying cooling mode and a dehumidifying heating mode. SOLUTION: In transfer from an off condition of an air conditioner unit 1 to a DEF control, in the case where a target blow temperature TAO is a low temperature of a suction air temperature Tin sucked to an evaporator or less, a dehumidifying cooling mode is selected in which an outdoor heat exchanger 23 is operated as a condenser, and in which an evaporator 24 is solely operated as a vaporizer. In the case where the target blow temperature TAO is higher than the suction air temperature Tin, a dehumidifing heating mode is selected in which the outdoor heat exchanger 23 and the evaporator 24 are simultaneously operated as a vaporizer. When dehumidification in a cabin is desired by a passenger, therefore, the dehumidifying modes are selected under consideration of properties of air sucked to the evaporator 24, thereby the target blow temperature TAO of air blown into the cabin in an electric car can be more easily formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner for dehumidifying the interior of a vehicle such as an electric vehicle having no engine cooling water or a vehicle equipped with an air-cooled engine. The present invention relates to an air conditioner for an electric vehicle, which dehumidifies or dehumidifies air from the air.

[0002]

2. Description of the Related Art The applicant of the present invention has disclosed, for example, Japanese Patent Application No. 8-158502 (filing date: June 1, 1996) as a vehicle air conditioner for air-conditioning the interior of a vehicle having no engine cooling water.
9th) was proposed. This air conditioner for electric vehicles operates the outdoor heat exchanger as a condenser by changing the refrigerant path in the refrigeration cycle when it is necessary to dehumidify the interior of the vehicle (particularly to remove the fogging of the windshield). The air conditioning operation mode is switched to a dehumidifying cooling mode in which the indoor evaporator is operated independently as an evaporator or a dehumidifying heating mode in which the outdoor heat exchanger and the indoor evaporator are operated in parallel as an evaporator. I try to remove the fogging of the window glass.

[0003] In the dehumidifying cooling mode, the refrigerant discharged from the discharge port of the refrigerant compressor circulates in the order of an indoor condenser, an outdoor heat exchanger, a decompression means, an indoor evaporator, and a refrigerant compressor (dehumidification). Cooling cycle). In the dehumidifying and heating mode, the refrigerant discharged from the outlet of the refrigerant compressor circulates in the order of an indoor condenser, a decompression unit, an outdoor heat exchanger, an indoor evaporator, and a refrigerant compressor (a dehumidifying and heating cycle).

[0004] In the above-described air conditioner for an electric vehicle, a switching condition (selection condition) between a dehumidifying cooling mode and a dehumidifying heating mode when it is necessary to dehumidify the cabin.
Are selected only by the outside air temperature. That is, when the outside air temperature is higher than the switching temperature (for example, 18 ° C.), the dehumidifying / cooling mode is selected to cool and dehumidify the vehicle interior, and when the outside air temperature is lower than the switching temperature (for example, 18 ° C.),
The dehumidifying and heating mode is selected to heat and dehumidify the cabin.

[0005]

However, in the above-described air conditioner for an electric vehicle, the rotation speed of the refrigerant compressor is changed based on the target blowing temperature of the air blown into the vehicle interior, so that the temperature setting switch is used. The temperature of the air blown into the passenger compartment is controlled so as to reach the desired temperature that is set.However, the ease of creating the target blowout temperature depends not only on the outside air temperature but also on the outside air humidity, inside air temperature, and the air volume of the blower. Is done. In particular, when the outside air humidity is high even when the outside air temperature is constant, the amount of heat absorbed by the indoor evaporator and the amount of heat released by the indoor condenser become larger than when the outside air humidity is low. For this reason, when the dehumidifying cooling mode and the dehumidifying cooling mode are selected only by the outside air temperature, it is necessary to change the switching temperature according to the outside air humidity, so that there is a problem that it is difficult to make the target outlet temperature.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to optimize a switching condition between a dehumidifying cooling mode and a dehumidifying heating mode so that a target blowing temperature calculated in consideration of a set blowing temperature, an inside air temperature, an outside air temperature, and the like. An object of the present invention is to provide an air conditioner for a vehicle which is easily manufactured.

[0007]

According to the first aspect of the present invention, when the dehumidification of the vehicle interior is desired, the target outlet temperature calculated in consideration of the set outlet temperature, the inside air temperature and the outside air temperature. However, when the temperature is lower than the suction temperature sucked into the cooling indoor heat exchanger, the dehumidifying cooling mode is selected,
The circuit is switched to the dehumidifying / cooling mode circulation circuit. Thereby, the refrigerant discharged from the refrigerant compressor flows in the order of the indoor heat exchanger for heating, the outdoor heat exchanger, the decompression means, and the indoor heat exchanger for cooling, and is sucked into the refrigerant compressor. At this time, the air sucked into the duct is cooled and dehumidified by the cooling indoor heat exchanger, then reheated by the heating indoor heat exchanger and blown out into the passenger compartment, whereby the passenger compartment is cooled and dehumidified. Is done.

If the target outlet temperature is higher than the suction temperature, the dehumidifying and heating mode is selected and the circuit is switched to the dehumidifying and heating mode circulation circuit. Thereby, the refrigerant discharged from the refrigerant compressor is heated by the indoor heat exchanger, the pressure reducing means,
The refrigerant flows in the order of the outdoor heat exchanger and the cooling indoor heat exchanger and is sucked into the refrigerant compressor. At this time, the air sucked into the duct is cooled and dehumidified by the cooling indoor heat exchanger, then reheated by the heating indoor heat exchanger and blown out into the vehicle interior, so that the interior of the vehicle is heated and dehumidified. Is done.

Accordingly, when the dehumidification of the passenger compartment is desired, the properties of the air sucked into the cooling indoor heat exchanger,
In consideration of the outside air temperature, the inside air temperature, and the target outlet temperature, a cooling mode dehumidification performed by switching to the dehumidifying cooling mode circulation circuit and a heating mode dehumidification performed by switching to the dehumidification heating mode circulation circuit are selected. Therefore, it becomes easier to set the target outlet temperature.

According to the second aspect of the present invention, an electric vehicle having no engine cooling water or an air-cooled type is used as a refrigerant compressor by using an electric refrigerant compressor rotated and driven by a drive motor. The interior of a vehicle such as an engine-equipped vehicle can be dehumidified. Further, by controlling the energization of the drive motor by an inverter serving as a drive power supply, the discharge amount of the refrigerant discharged from the refrigerant compressor is changed, that is, the amount of refrigerant circulating through the indoor heat exchanger for heating, and the indoor heat exchange for cooling. The amount of refrigerant circulating in the vessel can be easily adjusted. Therefore, only by changing the rotation speed of the drive motor, the blow-out temperature (actual blow-out temperature) of the air blown into the vehicle compartment can be made to substantially match the target blow-out temperature.

According to the third aspect of the invention, when the dehumidifying cooling mode is selected, the refrigerant discharged from the refrigerant compressor flows into the first indoor heat exchanger and heats the air in the duct. Later, the refrigerant flows into the second indoor heat exchanger through the outdoor heat exchanger and the decompression means, and is further sucked into the refrigerant compressor. At this time, the air sucked into the duct is cooled and dehumidified by the second indoor heat exchanger and then reheated by the first indoor heat exchanger and blown out into the vehicle interior, so that the vehicle interior is cooled and dehumidified. Is done.

When the dehumidifying and heating mode is selected, the refrigerant discharged from the refrigerant compressor flows into the first indoor heat exchanger and heats the air in the duct. Through the second indoor heat exchanger, and further sucked into the refrigerant compressor. At this time, the air sucked into the duct is cooled and dehumidified by the second indoor heat exchanger and then reheated by the first indoor heat exchanger and blown out into the vehicle interior, so that the vehicle interior is heated and dehumidified. Is done.

According to the fourth aspect of the present invention, when the dehumidifying cooling mode is selected, the refrigerant discharged from the refrigerant compressor flows into the refrigerant heat medium heat exchanger and heats the heat medium. The refrigerant flows into the second indoor heat exchanger through the outdoor heat exchanger and the pressure reducing means, and is further sucked into the refrigerant compressor. On the other hand, the heat medium is sent from the refrigerant heat medium heat exchanger to the first indoor heat exchanger by the operation of the heat medium circulation means. At this time, the air sucked into the duct is cooled and dehumidified by the second indoor heat exchanger and then reheated by the first indoor heat exchanger and blown out into the vehicle interior, so that the vehicle interior is cooled and dehumidified. Is done.

When the dehumidifying and heating mode is selected, the refrigerant discharged from the refrigerant compressor flows into the refrigerant heat medium heat exchanger to heat the heat medium, and then passes through the pressure reducing means and the outdoor heat exchanger. And flows into the second indoor heat exchanger, and is further sucked into the refrigerant compressor. On the other hand, the heat medium is sent from the refrigerant heat medium heat exchanger to the first indoor heat exchanger by the operation of the heat medium circulation means. At this time, the air sucked into the duct is cooled and dehumidified by the second indoor heat exchanger and then reheated by the first indoor heat exchanger and blown out into the vehicle interior, so that the vehicle interior is heated and dehumidified. Is done.

According to the fifth aspect of the present invention, when the dehumidifying / cooling mode is selected when dehumidification in the vehicle compartment is desired, the target outlet temperature and the temperature of the second indoor heat exchanger are changed. By controlling the heating amount adjusting means in accordance with
The amount of reheating of the air that has been cooled and dehumidified by the indoor heat exchanger is adjusted, and the rotation speed of the refrigerant compressor is controlled so that the temperature of the second indoor heat exchanger becomes the target temperature. The actual blowing temperature to be blown is brought closer to the target blowing temperature.

According to the sixth aspect of the present invention, when the dehumidification of the passenger compartment is desired and the dehumidifying / cooling mode is selected, the heating amount of the air in the duct by the heating amount adjusting means is reduced to a predetermined value or less. If the temperature decreases, the operation of the heat medium circulating means is stopped to reduce the operating cost. At this time, by controlling the rotation speed of the refrigerant compressor so that the target outlet temperature substantially matches the temperature of the second indoor heat exchanger, the refrigerant is blown into the vehicle interior from the duct while reducing the work load of the refrigerant compressor. The actual outlet temperature can be made to substantially match the target outlet temperature.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Structure of First Embodiment] FIGS. 1 to 7 show a first embodiment of the present invention, and FIG. 1 is a diagram showing an entire structure of an air conditioner for an electric vehicle. FIG. 2 is a diagram showing a control system of the air conditioner for an electric vehicle.

An air conditioner for an electric vehicle is provided with an air conditioner (actuator) in an air conditioner unit (air conditioner unit) 1 for air conditioning a vehicle interior of an electric vehicle (vehicle) on which a traveling motor M is mounted. EC
(Referred to as U).

The air conditioner unit 1 has an air conditioning duct 2 inside which forms an air passage for introducing conditioned air into the interior of an electric vehicle, a centrifugal blower for generating an air flow in the air conditioning duct 2, and a flow in the air conditioning duct 2. It includes a brine cycle for heating the air to heat the vehicle interior, a refrigeration cycle for cooling and dehumidifying the air flowing through the air conditioning duct 2 and dehumidifying the vehicle interior.

The air-conditioning duct 2 is disposed on the front side in the passenger compartment of the electric vehicle. The most upstream side (upwind side) of the air conditioning duct 2 is a part constituting an inside / outside air switching box, and is an inside air suction port 3 for taking in the vehicle interior air (hereinafter, referred to as inside air), and the vehicle outside air (hereinafter, outside air). Has an outside air suction port 4 for taking in air. Further, inside / outside air switching dampers 5 are rotatably supported inside the inside air suction port 3 and outside air suction port 4. The inside / outside air switching damper 5 is driven by an actuator (not shown) such as a servomotor to switch the suction port mode to an inside air circulation mode, an outside air introduction mode, or the like. The inside / outside air switching damper 5 constitutes inside / outside air switching means together with the inside / outside air switching box.

Further, on the downstream side (downwind side) of the air conditioning duct 2.
Is a defroster (DEF) outlet 11 that mainly blows warm air toward the inner surface of the windshield of the electric vehicle, and a face that mainly blows cool air toward the occupant's head and chest. (FACE) outlet 12,
And a foot (FOOT) outlet 13 for mainly blowing warm air toward the feet of the occupant. Further, inside each outlet, a defroster (DEF) damper 14, a face (FACE) damper 15, and a foot (FOO) are provided.
T) The damper 16 is rotatably supported. DEF,
The outlet switching door including the FACE and FOOT dampers 14 to 16 is driven by an actuator (not shown) such as a servomotor to set the outlet mode to face (FA).
CE) mode, bilevel (B / L) mode, foot (FOOT) mode, foot differential (F / D) mode or defroster (DEF) mode.

The centrifugal blower has a centrifugal fan 17 rotatably accommodated in a scroll case integrally formed with the air conditioning duct 2 and a blower motor 18 for driving the centrifugal fan 17. An air flow rate (rotational speed of the blower motor 18) is controlled based on a blower motor terminal voltage (blower voltage) applied via a (not shown).

The brine cycle includes a hot water heater 6, a brine refrigerant heat exchanger 7, a water pump 8, a combustion heater 9, and a hot water pipe (brine pipe) for connecting these in a ring shape. In the present embodiment, an antifreeze (for example, an ethylene glycol aqueous solution) or LLC (long life coolant) is used as warm water (heat medium, brine) circulating in the brine cycle.

The hot water heater 6 is equivalent to the heating indoor heat exchanger and the first indoor heat exchanger of the present invention, and is installed in the air conditioning duct 2 and passes therethrough by heat exchange with hot water flowing inside. An indoor air heater that heats air. At the air inlet and outlet of the hot water heater 6, the amount of air that passes through the hot water heater 6 (the amount of hot air) and the amount of air that bypasses the hot water heater 6 (the amount of cold air) are adjusted to the vehicle interior. Two air mixes (A /
M) The damper 19 is rotatably supported. These A / M dampers 19 correspond to the heating amount adjusting means of the present invention, and are driven by an actuator (not shown) such as a stepping motor or a servomotor.

The brine refrigerant heat exchanger 7 corresponds to the heating indoor heat exchanger and the refrigerant heat medium heat exchanger of the present invention, and has a double pipe structure made of a metal pipe having excellent heat conductivity such as an aluminum alloy. A hot water passage is formed on the inner peripheral side, and a refrigerant passage is formed on the outer peripheral side. The brine refrigerant heat exchanger 7 is installed outside the vehicle compartment and exchanges heat between low-temperature hot water (brine: heat medium) flowing in the hot water passage and high-temperature and high-pressure gas refrigerant flowing in the refrigerant passage. It operates as a hot water heater for heating and also operates as a condenser of a refrigeration cycle.

The water pump 8 corresponds to the heat medium circulating means of the present invention, and is a water pump that generates a circulating flow of hot water in a brine cycle by being activated by being energized. The combustion type heater 9 mixes fuel pumped from a fuel pump (not shown) with combustion air and burns, and heats hot water by heat exchange with combustion gas generated during the combustion. After the heat exchange with the hot water, the combustion gas is discharged to the atmosphere. However, this combustion type heater 9 is
When the outside air temperature is low (for example, 0 ° C. or less), the brine refrigerant heat exchanger 7 alone is used as an auxiliary heating device when the hot water cannot be sufficiently heated. The combustion type heater 9
Is to switch between two stages, "Hi", which has a high combustion amount (calorific value), and "Lo", which has a low combustion amount, by adjusting the amount of fuel supplied and the amount of combustion air pumped from the fuel pump. Can be.

The refrigerating cycle is also a heat pump cycle, and includes a refrigerant compressor 20, a brine refrigerant heat exchanger 7, a pressure reducing means described later, an outdoor heat exchanger 23, and an evaporator 2.
4. It is composed of an accumulator 25, a circulating circuit switching means to be described later, and a refrigerant pipe connecting these in a ring shape, and the circulating direction of the refrigerant changes based on each air conditioning operation mode. The normal air-conditioning operation mode of the present embodiment includes a cooling mode for cooling the vehicle interior, a dehumidification mode for dehumidifying the interior of the vehicle (dehumidification heating mode, dehumidification cooling mode, cooling mode), and heating the interior of the vehicle only with the heat pump. A heat pump heating mode, a combustion heating mode in which the vehicle interior is heated only by the combustion type heater 9, and the like are set. The air conditioning operation mode in the DEF control (dehumidification mode, DEF mode) of the present embodiment includes an outside air cooling mode in which the windshield is prevented from fogging, a dehumidification cooling mode in which the interior of the vehicle is cooled and dehumidified, and First and second dehumidifying and heating modes for heating and dehumidifying, an outside air heating mode for preventing the windshield from fogging and preventing the frost of the evaporator 24, a combustion heating mode for dehumidifying and heating the vehicle interior with only the combustion heater 9, and the like are set. ing.

The refrigerant compressor 20 is an electrically driven refrigerant compressor (compressor) for compressing the drawn gas refrigerant.
An air conditioner inverter 30 is provided as rotation speed control means for controlling the rotation speed of a drive motor (not shown) of the refrigerant compressor 20 based on the output signal of the ECU 10.
The power applied from the vehicle-mounted power supply V to the drive motor is continuously or stepwise variably controlled by the air conditioner inverter 30. Therefore, the refrigerant compressor 20
Changes the refrigerant discharge capacity by adjusting the rotation speed of the drive motor due to the change in the applied electric power, and adjusts the flow rate of the refrigerant circulating in the refrigeration cycle, so that the brine refrigerant heat exchanger 7 (hot water heater 6) The heating capacity and the cooling capacity (dehumidifying capacity) of the evaporator 24 are controlled.

In this embodiment, two first and second pressure reducing means 21 and 22 are provided as components corresponding to the pressure reducing means of the present invention. The first decompression unit 21 is a capillary tube that decompresses the refrigerant flowing from the brine refrigerant heat exchanger 7 in the heating mode and in the dehumidification mode (the first and second dehumidification heating modes and the outside air heating mode). Second decompression means 22
Indicates the cooling mode and dehumidifying mode (dehumidifying cooling mode,
This is a capillary tube for reducing the pressure of the refrigerant flowing from the outdoor heat exchanger 23 during the outdoor air cooling mode.

The outdoor heat exchanger 23 is installed outside the vehicle compartment and exchanges heat between the refrigerant flowing inside and the outside air blown by the electric fan 26. In the heating mode and the dehumidifying mode (the second dehumidifying and heating mode and the outside air heating mode), the outdoor heat exchanger 23 evaporates and vaporizes the low-temperature and low-pressure refrigerant depressurized by the first decompression means 21 by exchanging heat with the outside air. In a cooling mode and a dehumidifying mode (a dehumidifying cooling mode and an outside air cooling mode), it operates as a condenser that condenses and liquefies the refrigerant flowing from the brine refrigerant heat exchanger 7 by heat exchange with the outside air. Here, generally, the outdoor heat exchanger 23 is installed outside the vehicle compartment, which is apt to receive a traveling wind generated when the electric vehicle travels. Therefore, if the electric vehicle is running, the outdoor heat exchanger 2
When operating as an evaporator, the refrigerant flowing in the evaporator 3 has a larger heat absorption than the refrigerant flowing in the evaporator 24, and when operating as a condenser, the refrigerant has a higher heat release than the refrigerant flowing in the brine refrigerant heat exchanger 7. Becomes larger.

The evaporator 24 corresponds to the indoor heat exchanger for cooling and the second indoor heat exchanger of the present invention, and is installed in the air conditioning duct 2 on the downstream side (downwind side) of the hot water heater 6. In the cooling mode and in the dehumidifying mode (first and second dehumidifying and heating modes, dehumidifying and cooling mode, and outdoor air cooling mode), the low-temperature and low-pressure refrigerant decompressed by the second decompression means 22 and the first decompression means 21 is supplied to the air conditioning duct 2. It is operated as an evaporator that evaporates by heat exchange with air.
Thus, the refrigerant flowing inside the evaporator 24 evaporates by absorbing latent heat of heat (absorbing heat) from the air passing through the evaporator 24, thereby cooling and dehumidifying the air passing through the evaporator 24. The accumulator 25 is
The refrigerant that has flowed into the inside is separated into a liquid refrigerant and a gas refrigerant by gas-liquid separation to store the liquid refrigerant, and is operated as a gas-liquid separator that supplies only the gas refrigerant to the refrigerant compressor 20.

The circulating circuit switching means sets the circulation direction of the refrigerant in the refrigeration cycle to a cooling cycle (a path indicated by an arrow C in FIG. 1), a heating cycle (a path indicated by an arrow H in FIG. 1), and a dehumidification cycle (an arrow D in FIG. 1). 1) and a dehumidifying / heating cycle (the path indicated by arrows H and D in FIG. 1). Here, the cooling cycle corresponds to the dehumidifying cooling mode circulation circuit of the present invention, and the dehumidifying cycle corresponds to the dehumidifying heating mode circulation circuit of the present invention. In the present embodiment, as the circulation circuit switching means, three electromagnetic on-off valves (hereinafter referred to as electromagnetic valves) that open when energized (ON, ON) and close when energized is stopped (OFF, OFF). Abbreviated) VC, VH, VD are used.

The solenoid valve VC bypasses the first pressure reducing means 21 and is provided in a cooling refrigerant flow path connecting the brine refrigerant heat exchanger 7 and the outdoor heat exchanger 23. And the solenoid valve V
C transfers the refrigerant discharged from the refrigerant compressor 20 during the cooling cycle to the brine refrigerant heat exchanger 7 → the outdoor heat exchanger 23.
It is a cooling opening / closing means for opening a third refrigerant flow path which flows in the order of → second pressure reducing means 22 → evaporator 24 → accumulator 25 → refrigerant compressor 20. The solenoid valve VH bypasses the second pressure reducing means 22 and the evaporator 24 and
3 and an accumulator 25. The solenoid valve VH supplies the refrigerant discharged from the refrigerant compressor 20 during the heating cycle and the dehumidifying / heating cycle to the brine refrigerant heat exchanger 7 → the first pressure reducing means 21 → the outdoor heat exchanger 23 → the accumulator 25 → the refrigerant. This is a heating opening / closing unit that opens a first refrigerant flow path that flows in the order of the compressor 20. The solenoid valve VD bypasses the second pressure reducing means 22,
It is installed in a dehumidifying refrigerant channel connecting the first pressure reducing means 21 and the evaporator 24. The solenoid valve VD is connected to the refrigerant compressor 2 during the dehumidification cycle and the dehumidification heating cycle.
This is a dehumidifying opening / closing means for opening a second refrigerant flow path for flowing the refrigerant discharged from 0 to the brine refrigerant heat exchanger 7 → first pressure reducing means 21 → evaporator 24 → accumulator 25 → refrigerant compressor 20 in order.

The ECU 10 corresponds to the air-conditioning control device, the target outlet temperature determining means, and the suction temperature detecting means of the present invention, and includes a central processing unit (hereinafter referred to as a CPU) 31, RO,
It has an M32, a RAM 33, an A / D converter 34, interfaces 35 and 36, etc., and is itself known. The ECU 10 is operated by being supplied with electric power from a vehicle-mounted power supply V via a junction box J connected to a traveling inverter I for controlling the rotation speed of the traveling motor M.

Then, the ECU 10 controls the inside air temperature sensor 4
1. External temperature sensor 42, solar radiation sensor 43, refrigerant pressure sensor 44, post-evaporation temperature sensor 45, water temperature sensor 46, defrost sensor 47, water temperature sensor 48, and input signals input from operation panel 50 and control input in advance. Each air conditioner is controlled based on the program. That is, E
The CU 10 controls the operation state of each refrigeration device (actuator) based on input signals such as a detection value (detection signal) of each sensor and an operation value (operation signal) of the operation panel 50 and a control program input in advance. .

The inside air temperature sensor 41 is a means for detecting the inside air temperature (inside air temperature) of the vehicle cabin, which comprises a temperature sensing element such as a thermistor. Outside temperature sensor 42
Is an outside air temperature detecting means which comprises a temperature sensing element such as a thermistor and detects the air temperature outside the vehicle compartment (outside air temperature). The solar radiation sensor 43 is a solar radiation amount detecting means for detecting the amount of solar radiation into the vehicle interior. The refrigerant pressure sensor 44 is a refrigerant pressure detecting unit that detects the high pressure of the refrigeration cycle that is the discharge pressure of the refrigerant compressor 20.

The post-evaporation temperature sensor 45 corresponds to the evaporator temperature detection means of the present invention, and is composed of, for example, a temperature-sensitive element such as a thermistor, and detects the air temperature immediately after passing through the evaporator 24. Means. The water temperature sensor 46 is composed of a temperature-sensitive element such as a thermistor,
This is a heat medium temperature detecting means for detecting the inlet water temperature of the hot water type heater 6. The defrost sensor 47 is a refrigerant temperature detecting unit that includes a temperature sensing element such as a thermistor, and detects the refrigerant temperature at the inlet of the outdoor heat exchanger 23 in the heating mode and the dehumidifying heating mode. The water temperature sensor 48 is composed of, for example, a temperature-sensitive element such as a thermistor, and detects the outlet water temperature of the combustion heater 9.

As shown in FIG. 3, a temperature setting switch 51, a blower off switch 52,
Auto switch 53, air volume setting switch 54, mode setting switch 55, liquid crystal display 56, inside air circulation setting switch 57, front defroster switch (hereinafter referred to as DEF switch) 58, rear defogger switch 59, air conditioner switch 60, combustion type heater switching A switch 61 and a combustion-type heater-off switch 62 are provided.

The temperature setting switch 51 is used to set the rotation speed of the refrigerant compressor 20 or to set the A / M damper 19
Is a blowout temperature setting means for setting the opening degree of the airbag and setting the blowout temperature of the air blown into the vehicle interior. The mode setting switch 55 includes DEF, FACE, and FOOT dampers 14 to 16.
By controlling the opening and closing of the air outlet mode, the air outlet mode can be changed to a face (FACE) mode, a bi-level (B / L) mode,
Foot (FOOT) mode or foot differential (F / D)
This is a switch for instructing to set one of the modes. The inside air circulation setting switch 57 is a switch that sets the suction port mode to the inside air circulation mode by controlling the opening and closing of the inside / outside air switching damper 5. The DEF switch 58 corresponds to the dehumidification mode setting means of the present invention, and is an air outlet mode switching instruction means for instructing to set the air outlet mode to a defroster (DEF, dehumidification) mode.

[Operation of First Embodiment] Next, the operation of the air conditioner for an electric vehicle according to the present embodiment will be described with reference to FIGS. First, a control process of the ECU 10 according to the present embodiment will be described with reference to FIGS. here,
FIG. 4 is a flowchart showing main control processing by the ECU 10.

First, when electric power is supplied from the vehicle power supply V to the ECU 10, the routine shown in FIG. 4 is started, and initialization and initialization are performed (step S1). Subsequently, the set outlet temperature T set by the temperature setting switch 51
set (blowout temperature setting means: step S
2). Subsequently, various operation signals from the operation panel 50 (for example, the air volume signal of the centrifugal blower set by the air volume setting switch 54, the mode setting switch 55 and the DEF switch 5).
Then, the air outlet mode signal set at 8 and the internal air circulation mode signal set at the internal air circulation setting switch 57 are read (dehumidification mode setting means: step S3). Subsequently, the inside air temperature TR detected by the inside air temperature sensor 41 and the outside air temperature sensor 4
Each sensor signal is read from various sensors such as the outside air temperature TAM detected in step 2, the solar radiation amount TS detected by the solar radiation sensor 43, the post-evaporation temperature TE detected by the post-evaporation temperature sensor 45, and the hot water temperature TW detected by the water temperature sensor 46. (Inside air temperature detection means, outside air temperature detection means, evaporator temperature detection means: step S4).

Subsequently, based on the following equation (1) stored in the ROM 32 in advance, the target blowing temperature TAO of the air blown into the passenger compartment of the electric vehicle is calculated (target blowing temperature determining means: step S5).

## EQU1 ## TAO = Kset × Tset−KR × TR−K
AM × TAM-KS × TS + C

Tset is an outlet temperature set by the temperature setting switch 51, TR is an inside air temperature detected by the inside air temperature sensor 41, TAM is an outside air temperature detected by the outside air temperature sensor 42, and TS is a sunshine sensor 43. Is the amount of solar radiation. Kset, KR, KAM, and KS are gains, and C is a correction constant.

Subsequently, based on a characteristic diagram (map) (not shown) stored in the ROM 32 in advance, the target blowing temperature (TAO)
Is determined (step S6). Then, ROM
An outlet mode corresponding to the target outlet temperature (TAO) is determined from a characteristic diagram (map) (not shown) stored in the memory 32 (step S7). When the DEF switch 58 is pressed, the DEF damper 14 is moved to the position indicated by the alternate long and short dash line in FIG.
The OOT damper 16 is set to the position indicated by the solid line in FIG. When the occupant operates the mode setting switch 55, the mode is determined to be the outlet mode corresponding to the operation.

Here, in determining the outlet mode,
Target outlet temperature (TAO) or target hot water temperature (TWO)
From low to high temperature, FACE mode, B
/ L mode, FOOT mode, and F / D mode. Note that the FACE mode is a DEF
The damper 14 is set to the solid line position in FIG. 1, the FACE damper 15 is set to the solid line position in FIG. 1, and the FOOT damper 16 is set to the dashed line position in FIG. 1, and the air outlet blows out conditioned air toward the occupant's head and chest in the passenger compartment. Mode. What is B / L mode?
The DEF damper 14 is positioned at the solid line in FIG.
5 is an outlet mode in which the conditioned air is blown toward the occupant's head and chest and feet in the passenger compartment with the solid line position in FIG. 1 and the FOOT damper 16 set in the dashed line position in FIG.

In the FOOT mode, the DEF damper 14 is set to a slightly open position, the FACE damper 15 is set to the dashed line position in FIG. 1, and the FOOT damper 16 is set to the dashed line position in FIG. This is an outlet mode in which air blows toward the feet of the occupant and about 20% of the conditioned air blows toward the inner surface of the windshield. The F / D mode is
The EF damper 14 is set to the dashed line position in FIG. 1, the FACE damper 15 is set to the dashed line position in FIG. 1, and the FOOT damper 16 is set to the dashed line position in FIG. This is an outlet mode in which the same amount is blown out at a time.

Subsequently, from a characteristic diagram (map) (not shown) stored in the ROM 32 in advance, the target blowing temperature (TAO)
Is determined (step S8).
Here, in determining the suction port mode, when the inside air circulation setting switch 57 is pressed, the suction port mode is set to the inside air circulation mode. When the DEF switch 58 is pressed, the outside air introduction mode is set even if the inside air circulation setting switch 57 is pressed. However, when the inside air circulation setting switch 57 is pressed thereafter, the suction port mode is set. Is set to the inside air circulation mode.

The inside air circulation mode means that the inside / outside air switching damper 5 is set at the position indicated by the dashed line in FIG.
Is opened, the outside air suction port 4 is closed, and 100
% Suction mode for introducing inside air. The outside air introduction mode is a suction mode in which the inside / outside air switching damper 5 is set to the solid line position in FIG. 1, the inside air suction port 3 is closed, and the outside air suction port 4 is opened to introduce 100% outside air into the air conditioning duct 2. Mouth mode. Alternatively, the inside / outside air switching damper 5 may be set to the neutral position, and the inside / outside air mode in which both the inside air suction port 3 and the outside air suction port 4 are opened to introduce the inside air and outside air into the air conditioning duct 2 may be set.

Subsequently, the subroutine shown in FIG. 5 is called, and the air-conditioning operation mode is determined according to the target blowing temperature TAO and the like calculated in step S5 of the flowchart in FIG. 4 (step S9). Subsequently, a subroutine shown in FIG. 6 is called to determine the target rotation speed of the refrigerant compressor 20 and control the temperature of the air blown into the vehicle interior (rotation speed control means: step S10).

Subsequently, the inside / outside air switching damper 5, the water pump 8, the combustion heater 9, the DEF, FACE, and the FOOT dampers 14 to 14 are obtained so as to obtain the respective control states calculated or determined in steps S5 to S8. 16, blower motor 18, air conditioner inverter 30, electric fan 26, solenoid valves VC, VH, VD and A / M damper 1
A control signal is output to each actuator such as 9 (step S11). Then, in step S12, the process returns to step S2 after waiting for a control cycle time τ (for example, 0.5 seconds to 2.5 seconds).

[Air-Conditioning Operation Mode Determination Control of First Embodiment] Next, the air-conditioning operation mode determination control by the ECU 10 of this embodiment when shifting from the OFF state to the DEF control will be described with reference to FIGS. . Here, FIG. 5 is a subroutine showing the air-conditioning operation mode determination control by the ECU 10.

First, it is determined whether or not the DEF switch 58 has been pressed (step S21). This judgment result is NO
In the case of, it is determined whether or not the air conditioner switch 60 is turned on (step S22). This judgment result is N
In the case of O, the process exits the subroutine of FIG. If the determination result of step S22 is YES, the air-conditioning operation mode is selected according to the temperature control control. For example, the air-conditioning operation mode is selected according to the target outlet temperature TAO calculated in step S5 of the flowchart of FIG. 4 and the outside air temperature TAM detected by the outside air temperature sensor 42 (step S23). Thereafter, the process exits the subroutine of FIG.

If the result of the determination in step S21 is YES
, The outside air temperature TA detected by the outside air temperature sensor 42
M is the suction temperature T of the air sucked into the evaporator 24.
in (suction temperature detecting means: step S24). Here, when shifting from the OFF state to the DEF control, since the suction port mode is the 100% outside air introduction mode, the outside air temperature TAM is used as the suction temperature Tin. Subsequently, FIG.
An air-conditioning operation mode corresponding to the target outlet temperature TAO, the outside air temperature TAM and the suction temperature Tin calculated in step S5 is selected (step S25). Thereafter, the process exits the subroutine of FIG.

When the DEF switch 58 on the operation panel 50 is pressed while the air conditioner unit 1 is in the OFF state, the ECU 10 performs the DEF control shown in Table 1 below. Table 1 shows each air conditioner (actuator) under DEF control.
The operation state of is shown.

[Table 1]

Even if the inside air circulation setting switch 57 is manually pressed before the DEF control is started and the inside air circulation mode is commanded, the DEF control is started by fixing the 100% outside air introduction mode. However, in the outside air cooling mode of the DEF control, in the case of the automatic air conditioner, the air conditioning mode is always fixed to the 100% outside air introduction mode. However, when the inside air circulation setting switch 57 is manually pressed and the inside air circulation mode is commanded, this is accepted.

The selection of the air conditioning operation mode of the DEF control is performed as described later. That is, when the relationship shown in FIG. 7 and the following equation (2) or equation (3) previously stored in the ROM is satisfied, the water pump 8 is turned off as shown in Table 1 and The outside air cooling mode for switching the refrigeration cycle to the cooling cycle is selected. When (TAM−15 ° C.) is higher than (3 ° C.), equation (2) is adopted. When (TAM−15 ° C.) is lower than (3 ° C.), equation (3) is used. Is adopted.

[Equation 2] TAO ≦ TAM-10 ° C.

[Equation 3] TAO ≦ 3 ° C.

If the relationship shown in FIG. 7 and the following equation (4) stored in the ROM is satisfied, the water pump 8 is turned on and the refrigeration cycle is turned on as shown in Table 1. Is switched to the cooling cycle, and the dehumidifying cooling mode is selected.

## EQU4 ## TAM-10 ° C. <TAO ≦ Tin

If the relationship shown in FIG. 7 and the following equation (5) stored in the ROM in advance is satisfied,
As shown in Table 1, the water pump 8 is turned on,
Select the dehumidifying heating mode that switches the refrigeration cycle to the dehumidifying cycle.

[Equation 5] TAO> Tin

[Blow Temperature Control During DEF Control of First Embodiment] Next, blow temperature control during DEF control by the ECU 10 according to the present embodiment will be described with reference to FIGS. Here, FIG. 6 is a subroutine showing blow-out temperature control (rotational speed control of the refrigerant compressor) during DEF control by the ECU 10.

First, it is determined whether or not the DEF switch 58 has been pressed (step S31). This judgment result is NO
In this case, the subroutine of FIG. 6 is exited. If the determination result of step S31 is YES, it is determined whether the dehumidifying and heating mode is selected as the air conditioning operation mode (step S32). If the result of this determination is YES, the air volume V (m ³
/ H) to determine the temperature efficiency φ (temperature efficiency determining means:
Step S33). Here, the temperature efficiency φ is calculated based on a characteristic diagram (not shown) of the air flow rate V and the temperature efficiency φ of the centrifugal blower obtained according to the operation state of the centrifugal blower.

Subsequently, the target hot water temperature TWO is determined by a method described later (target heat medium temperature determining means: step S3).
4). That is, based on the post-evaporation temperature TE detected by the post-evaporation temperature sensor 45, the target outlet temperature TAO determined in step S5 of the flowchart of FIG. 4, and the temperature efficiency φ determined in step S21, the target hot water temperature TWO is calculated by the following equation (6).
It is calculated based on the following equation.

TWO = (TAO-TE) / φ + TE

Subsequently, based on the temperature deviation between the target hot water temperature TWO and the inlet water temperature (hereinafter referred to as hot water temperature) TW of the hot water heater 6 detected by the water temperature sensor 46, the refrigerant compressor 2
0 target rotation speed (target rotation speed determination means:
Step S35). Thereafter, the process exits the subroutine of FIG. Then, step S11 of the flowchart of FIG.
Then, the post-evaporation temperature TE detected by the post-evaporation temperature sensor 45
Is maintained at the freezing limit temperature (frost limit temperature, for example, 2 ° C.), and the rotation speed of the refrigerant compressor 20 is changed to the target hot water temperature TWO so that the actual blow temperature TA blown into the vehicle interior becomes the target blow temperature TAO. Is controlled according to the temperature deviation between the temperature and the hot water temperature TW (TWO control).

Here, step S in the subroutine of FIG.
The target hot water temperature TWO determined in step 34 is, for example, DEF
If the temperature is related to the temperature of the air blown out from the air outlet 11 toward the inner surface of the windshield, the air blown out to the inner surface of the windshield can be set only by setting the blower temperature desired by the occupant using the temperature setting switch 51 or the like. Temperature reaches a temperature that meets the occupant's wishes.

If the decision result in the step S32 is NO, it is determined whether or not the dehumidifying / cooling mode is selected as the air conditioning operation mode (step S36). If the result of this determination is YES, it is determined whether the target damper opening (SW) of the A / M damper 19 is 0 (%) (step S37). If this determination is NO,
In the manner described above, the air volume V of the air passing through the hot water heater 6
The temperature efficiency φ is determined from (m ³ / h) (temperature efficiency determining means: step S38).

Subsequently, the target damper opening (SW) of the two A / M dampers 19 is calculated based on the following equation (step S39).

(7) SW = ｛(TAO-TE) / φ (TW-T
E)｝ × 100 (%) Here, SW is 0% for MAXCOOL (fully closed) and 100% for MAXHOT (fully open).

Subsequently, the target rotation speed of the refrigerant compressor 20 is determined so that the post-evaporation temperature TE detected by the post-evaporation temperature sensor 45 approaches the freezing limit temperature (for example, 2 ° C.) (step S40). Thereafter, the process exits the subroutine of FIG. Then, step S1 of the flowchart of FIG.
1, the post-evaporation temperature T detected by the post-evaporation temperature sensor 45
The rotation speed of the refrigerant compressor 20 is controlled while maintaining E at the freezing limit temperature (for example, 2 ° C.), and the A / M damper 19 is controlled so that the actual blow temperature TA blown into the vehicle interior becomes the target blow temperature TAO. Is controlled in accordance with the target blowout temperature TAO, the post-evaporation temperature TE, and the hot water temperature TW (A / M damper control).

When the result of the determination in step S36 is NO, and when the result of the determination in step S37 is YES,
Since the outside air cooling mode is selected as the air conditioning operation mode, the post-evaporation temperature TE detected by the post-evaporation temperature sensor 45 is used.
The target rotation speed of the refrigerant compressor 20 is determined so that the target air temperature matches the target outlet temperature TAO (TE = TAO) (step S41). Thereafter, the process exits the subroutine of FIG.
Then, in step S11 of the flowchart of FIG.
The rotational speed of the refrigerant compressor 20 is controlled in accordance with the target blowout temperature TAO such that the post-evaporation temperature sensor 45 detected by the post-evaporation temperature sensor 45 matches the target blowout temperature TAO (T
E = TAO control).

[DEF Control of First Embodiment] Next, the air conditioner unit 1 is turned off by the ECU 10 of the present embodiment.
The operation of each actuator when shifting from the state to the DEF control will be described with reference to FIGS.

(Dehumidifying and Heating Mode) When the occupant presses the DEF switch 58 and desires to remove the fogging of the windshield, as shown in the characteristic diagram of FIG. 7A, the target outlet temperature TAO becomes lower than the suction temperature Tin. If the temperature is also high, the dehumidifying and heating mode is selected as the air conditioning operation mode. In this case, the water pump 8 and the refrigerant compressor 20 are turned on.
Then, the two A / M dampers 19 are fixed to the MAXHOT, the solenoid valve VC is turned off, and the solenoid valves VH and VD are ON-OFF controlled according to the post-evaporation temperature TE. At this time, the inlet mode is fixed to the outside air introduction mode, and the outlet mode is fixed to the DEF mode.

1) First dehumidifying and heating mode Then, the temperature TE after evaporation is the freezing limit temperature (for example, 2 ° C.)
If the temperature is equal to or higher than the first predetermined temperature (for example, 2.5 ° C.), the solenoid valve VH is turned off and the solenoid valve VD is turned on, so that the first dehumidification in which the evaporator 24 is operated independently as an evaporator is used. The heating mode is set. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the dehumidification cycle (the direction of arrow D), and the brine refrigerant heat exchanger 7 → the first pressure reducing means 21 → the solenoid valve VD → the evaporator 2
4 → The accumulator 25 → The refrigerant compressor 20 circulates. On the other hand, the hot water heated by the condensation heat of the refrigerant when passing through the brine refrigerant heat exchanger 7 is circulated to the hot water heater 6 arranged on the lee side of the evaporator 24.

At this time, the air conditioning duct 2
The outside air sucked into the inside is cooled and dehumidified when passing through the evaporator 24 to become low humidity air. All the air that has passed through the evaporator 24 is supplied to the hot water heater 6.
After being reheated when passing through, the air is blown out from the DEF outlet 11 toward the inner surface of the windshield. As a result, the fogging of the windshield is removed, and the vehicle interior is heated and dehumidified. Further, the outdoor heat exchanger 23
Is not operated as an evaporator, the outdoor heat exchanger 23 can be defrosted.

2) Second dehumidifying and heating mode When the post-evaporation temperature TE is a temperature between the first predetermined temperature and the second predetermined temperature (for example, 1.5 ° C. to 2.5 ° C.),
When both the solenoid valves VH and VD are turned ON, the second dehumidifying heating mode is set in which the outdoor heat exchanger 23 and the evaporator 24 are operated in parallel as an evaporator. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 is:
The refrigerant flows through the dehumidifying and heating cycle (the path indicated by the arrow HD in FIG. 1), and the brine refrigerant heat exchanger 7 → the first pressure reducing means 2
After passing through No. 1, it is divided into one passing through the outdoor heat exchanger 23 → the solenoid valve VH and one passing through the solenoid valve VD → the evaporator 24. On the other hand, the hot water heated by the heat of condensation of the refrigerant in the brine refrigerant heat exchanger 7 is circulated to the hot water heater 6.

At this time, the air conditioning duct 2
The outside air sucked into the inside is cooled and dehumidified when passing through the evaporator 24 to become low humidity air. All the air that has passed through the evaporator 24 is supplied to the hot water heater 6.
After being reheated when passing through, the air is blown out from the DEF outlet 11 toward the inner surface of the windshield. This removes the fogging of the windshield,
The vehicle interior is heated and dehumidified.

Here, as described above, in the dehumidifying and heating mode B, the outdoor heat exchanger 23 is operated as an evaporator in parallel with the evaporator 24. In addition, when the electric vehicle is traveling, the traveling wind is also blown to the outdoor heat exchanger 23, so that the amount of heat absorbed by the outdoor heat exchanger 23 is larger than that of the evaporator 24, so that the outside air sucked into the air conditioning duct 2. The amount of heat absorbed by the refrigerant passing through the inside of the evaporator 24 decreases. Further, the amount of heat given to the hot water from the refrigerant in the brine refrigerant heat exchanger 7 is different from that in the first dehumidifying heating mode in which the evaporator 24 is operated alone as the evaporator, and the outdoor heat exchanger 23 is operated as the evaporator. Increases by the amount of heat absorption due to heat. As a result, the heating capacity in the vehicle interior is improved, so that the target outlet temperature TAO can be easily made.

3) Third dehumidification heating mode (outside air heating mode) Further, the post-evaporation temperature TE becomes the freezing limit temperature (for example, 2 ° C.).
When the temperature is equal to or lower than the second predetermined temperature (for example, 1.5 ° C.), the solenoid valve VH is turned on and the solenoid valve VD is turned off, so that the outdoor heat exchanger 23 operates alone as an evaporator. The third dehumidifying heating mode (outside air heating mode) is set. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the heating cycle (in the direction of arrow H),
Brine refrigerant heat exchanger 7 → first pressure reducing means 21 → outdoor heat exchanger 23 → solenoid valve VH → accumulator 25 → refrigerant compressor 20 circulates. On the other hand, the hot water heated by the heat of condensation of the refrigerant in the brine refrigerant heat exchanger 7 circulates through the hot water heater 6.

The outside air sucked into the air conditioning duct 2 from the outside air suction port 4 dissolves frost adhering to the surface of the evaporator 24 when passing through the evaporator 24, and is heated when passing through the hot water heater 6. After that, the air is blown from the DEF outlet 11 toward the inner surface of the windshield. As a result, fogging of the windshield is removed, frost (frost) of the evaporator 24 can be suppressed even when the outside air temperature TAM (suction temperature Tin) is low, and the outside of the vehicle can be heated. Here, the outside air temperature TAM
When the (suction temperature Tin) drops to, for example, 0 ° C. or less, the refrigerant compressor 20 is turned off and the combustion type heater 9 is set to Hi.
-Control the Lo operation.

(Dehumidifying / Cooling Mode) When the occupant presses the DEF switch 58 and desires to remove the fogging of the windshield, as shown in the characteristic diagram of FIG. 7A, the target outlet temperature TAO is lower than the suction temperature Tin. At low temperature and FIG.
As shown in the characteristic diagram of (b), when the target outlet temperature TAO is higher than (outside air temperature TAM−10 ° C.), the dehumidifying cooling mode is selected as the air conditioning operation mode. In this case, the water pump 8 and the refrigerant compressor 20
N, and the two A / M dampers 19 are operated in accordance with the target blowing temperature TAO, the post-evaporation temperature TE, and the like.
OL, the solenoid valve VC is turned on, and the solenoid valve V
H and VD are turned off. Also at this time, the inlet mode is fixed to the outside air introduction mode, and the outlet mode is fixed to the DEF mode.

Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the cooling cycle (in the direction of arrow C), and the brine refrigerant heat exchanger 7 → the solenoid valve VC → the outdoor heat exchanger 23 → the second pressure reducing means. 22 → evaporator 24 → accumulator 25 → refrigerant compressor 20. On the other hand, the hot water heated by the heat of condensation of the refrigerant in the brine refrigerant heat exchanger 7 is similarly circulated to the hot water heater 6.

At this time, the air-conditioning duct 2
The outside air sucked into the inside is cooled and dehumidified when passing through the evaporator 24 to become low humidity air. The air that has passed through the evaporator 24 passes through the hot water heater 6 according to the opening of the A / M damper 19 and is reheated.
The air is blown out from the DEF outlet 11 toward the inner surface of the windshield. Thereby, fogging of the windshield is removed.

Here, in the dehumidifying and cooling mode, the outdoor heat exchanger 23 is operated as a condenser. Similarly, when the electric vehicle is running, the traveling wind is also blown to the outdoor heat exchanger 23, so that the discharge of the refrigerant in the outdoor heat exchanger 23 is smaller than the amount of the heat released by the brine refrigerant heat exchanger 7. The amount of heat increases and the amount of heat given to the warm water from the refrigerant in the brine refrigerant heat exchanger 7 decreases. Therefore, the outside air sucked into the air-conditioning duct 2 is cooled and dehumidified by the evaporator 24 and then reheated when passing through the hot-water heater 6. For this reason, it is easy to make the target blowing temperature TAO in the dehumidifying cooling mode, in which a temperature lower than the target blowing temperature TAO in the dehumidifying and heating mode is calculated, and the interior of the vehicle compartment is cooled and dehumidified.

(Outdoor Air Cooling Mode) When the occupant presses the DEF switch 58 and desires to remove the fogging of the windshield, as shown in the characteristic diagram of FIG. When the temperature is low (−10 ° C.) or lower, or when the target outlet temperature TAO is low (3 ° C. or lower), the outside air cooling mode is selected as the air conditioning operation mode. In this case, the water pump 8 is turned off, the refrigerant compressor 20 is turned on, and the two A / M dampers 19 are
AXCOOL is fixed, the solenoid valve VC is turned on, and the solenoid valves VH and VD are turned off. At this time, the inlet mode is set to the outside air introduction mode, and the outlet mode is set to the DEF mode.

Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the cooling cycle (in the direction of arrow C), and the refrigerant compressor 20 → the brine refrigerant heat exchanger 7 (used simply as a refrigerant passage) → the solenoid valve VC → outdoor heat exchanger 23 →
It circulates like the second pressure reducing means 22 → evaporator 24 → accumulator 25 → refrigerant compressor 20.

At this time, the air conditioning duct 2
The outside air sucked into the inside is cooled and dehumidified when passing through the evaporator 24 to become low-humidity air, bypasses the hot water heater 6, and then blows out from the DEF outlet 11 toward the inner surface of the windshield. Is done. Thus, the anti-fog performance of the windshield can be sufficiently obtained, and the operation of the electric water pump 8 can be stopped, so that power and power consumption are reduced, and the traveling distance of the electric vehicle is extended.

[Effects of the First Embodiment] Here, in the dehumidifying cooling mode in which the outdoor heat exchanger 23 is operated as a condenser and the evaporator 24 is operated independently as an evaporator, the refrigerant compressor is operated in accordance with the target outlet temperature TAO. Investigation was conducted to determine the temperature range in which the actual blowing temperature TA blown into the vehicle cabin could be made by controlling the rotation speed of the A / M damper 20, and the A / M damper 19 was subjected to MAXHOT, that is, all the air passing through the evaporator 24. In the case of reheating with the 100% hot water type heater 6, it was found that the range was represented by the following equation (8) in the present embodiment.

TA <Tin + α ° C. where α = −1 ° C. to + 3 ° C., and Tin is the evaporator 2
4 is the suction temperature of the air sucked into 4.

In view of the above, if the DEF switch 58 is pressed to dehumidify the vehicle interior (especially removing the fogging of the windshield), the suction mode is changed to the outside air introduction mode (100% outside air introduction). Therefore, the suction temperature Tin can be replaced with the outside air temperature TAM. That is, when the target outlet temperature TAO desired at the time of the DEF control is higher than the outside air temperature TAM, the dehumidifying and heating mode is selected as the air conditioning operation mode, and when the target outlet temperature TAO is lower than the outside air temperature TAM, It is desirable to select the dehumidifying and cooling mode as the operation mode.

Therefore, in the present embodiment, as described above, when shifting from the OFF state of the air conditioner unit 1 to the DEF control, the dehumidifying heating mode and the dehumidifying cooling mode are utilized by using the target blowing temperature TAO and the suction temperature Tin. And try to choose. That is, the target outlet temperature T
When AO is at a low temperature equal to or lower than the outside air temperature TAM, selecting the dehumidifying / cooling mode makes it easier to produce a target outlet temperature TAO that is set lower. Also, the target outlet temperature TA
When O is higher than the outside air temperature TAM, selecting the dehumidifying and heating mode makes it easier to produce a target outlet temperature TAO that is set higher.

The target blowing temperature TAO is set by always setting the post-evaporation temperature TE to 3 ° C., which is the freezing (frosting) prevention temperature, and reheating (reheating) by the hot water heater 6. Power consumption and power consumption are increased, and the running distance of the electric vehicle is shortened. For this reason, when the DEF control is being performed in the dehumidifying and cooling mode, if the actual blow temperature TA does not fall to the target blow temperature TAO even if the reheat amount is minimized, that is, A according to the target blow temperature TAO The A / M damper 19 controls the MAXCOOL (SW
= 0%), the rotational speed of the refrigerant compressor 20 is set to TAO in the outside air cooling mode (normal cooling cycle).
I try to control. At this time, in this embodiment,
Since the rotational speed of the refrigerant compressor 20 is increased or decreased so that the post-evaporation temperature TE becomes the target outlet temperature TAO, the power consumption and power consumption of the refrigerant compressor 20 are reduced, and the traveling distance of the electric vehicle is also increased.

Further, the outside air is kept at a temperature of 10 ° C. to 18 ° C. below the outside air temperature.
It has been confirmed through repeated actual vehicle tests that the windshield and the side window glass can be prevented from fogging if they are cooled and dehumidified by about ° C. Therefore, when the relationship of the following equation 9 is satisfied, the refrigerant compressor 20 is controlled so that the post-evaporation temperature TE directly reaches the target blowing temperature TAO without closing the A / M damper 19 (MAXCOOL) and performing reheating. It is desirable to increase or decrease the rotation speed of the motor.

TAO ≦ TAM + β ° C. where β = + 10 ° C. to + 18 ° C.

As described above, when the outside air cooling mode is selected when dehumidification is required, the operation of the electric water pump 8 of the brine cycle can be stopped. And the anti-fog performance of the side window glass can be obtained sufficiently.

[Structure of the Second Embodiment] FIG. 8 shows a second embodiment of the present invention, and is a view showing the entire structure of an air conditioner for an electric vehicle.

The refrigeration cycle of this embodiment includes a refrigerant compressor 20 whose rotational speed is inverter-controlled, a condenser 71 into which the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows, and a pressure reduction of the refrigerant flowing out from the condenser 71. Decompressing means comprising first and second decompressors 21 and 22, an outdoor heat exchanger 23 installed outside the air conditioning duct 2, an evaporator 24 installed inside the air conditioning duct 2, an accumulator 25 for separating gas and liquid, a refrigeration cycle It is composed of a circulating circuit switching means composed of solenoid valves VC, VH, VD for switching the flow direction of the refrigerant inside, and a refrigerant pipe connecting these in a ring shape.

The condenser 71 corresponds to the heating heat exchanger and the first indoor heat exchanger of the present invention.
Is installed downstream of the evaporator 24 within the
This is a condenser that heats the air that passes by the heat of condensation of the refrigerant flowing inside. The capacitor 71 has a capacitor 7
Two air mixes as air amount adjusting means for adjusting the amount of air passing through 1 (the amount of hot air) and the amount of air bypassing the condenser 71 (the amount of cool air) to adjust the temperature of the air blown into the vehicle interior. (A / M) A damper 72 is rotatably supported. These A / M dampers 72 are actuators (not shown) such as stepping motors and servo motors.
Driven by

In the present embodiment, when the air conditioner unit 1 is shifted from the OFF state to the DEF control, the refrigeration cycle is operated in the dehumidification / cooling cycle, and the refrigeration cycle is set in the dehumidification cycle and the dehumidification / heating cycle. Alternatively, a dehumidifying heating mode operating in a heating cycle is selected. In addition, as a cooling cycle, the refrigerant compressor 2
By providing a refrigerant flow path through which the refrigerant discharged from the discharge port 0 can bypass the condenser 71 and flow directly into the outdoor heat exchanger 23 via the solenoid valve VC, the refrigerant flow in the dehumidification mode of the first embodiment is provided. The same operation and effect as in the outside air cooling mode can be obtained.

Also in the present embodiment, when the DEF switch 58 is depressed and it is desired to dehumidify the interior of the vehicle (particularly, to remove the fogging of the windshield), the target outlet temperature TAO and the suction temperature Tin are compared. Since the dehumidifying heating mode and the dehumidifying cooling mode are selected based on the comparison result, the target outlet temperature TAO can be easily made without introducing complicated control for changing the switching temperature according to the outside air humidity. Become.

[Other Embodiments] In this embodiment, the present invention is applied to an air conditioner for an electric vehicle. However, the present invention is applied to an air conditioner for a vehicle equipped with an air-cooled engine or a water-cooled engine. Is also good. In the present embodiment, the present invention is used only when the air conditioner unit 1 shifts from the OFF state to the DEF control. However, when the air conditioner unit 1 shifts from the temperature control state (temperature control state) to the DEF control, the present invention is used. Mode setting switch 5
The present invention may be used for FOOT control or F / D control when the FOOT mode or F / D mode is selected according to FIG.

In this embodiment, the outside air temperature sensor 42 is used as the suction temperature detecting means for detecting the suction temperature Tin of the air sucked into the evaporator (cooling indoor heat exchanger, second indoor heat exchanger) 24. A suction temperature sensor may be used as suction temperature detecting means for detecting the suction temperature Tin of the air sucked into the cooling indoor heat exchanger or the second indoor heat exchanger. In the present embodiment, the post-evaporation temperature sensor 45 that detects the air temperature immediately after passing through the evaporator 24 is used as the evaporator temperature detection means. However, the evaporator (second indoor heat exchanger) 24 is used as the evaporator temperature detection means. A temperature sensor that detects the surface temperature (fin temperature) or the evaporation temperature may be used.

In this embodiment, the inlet water temperature of the hot water heater 6 detected by the water temperature sensor 46 is used as the hot water temperature TW, but the outlet water temperature of the combustion heater 9 detected by the water temperature sensor 48 is used as the hot water temperature TW. Is also good. The water temperature at any point in the brine cycle may be read as the hot water temperature TW. In the present embodiment, an air mix temperature control method for adjusting the opening of the A / M damper 19 to adjust the temperature of the air blown into the vehicle compartment is used as the heating amount adjusting means. A reheat-type temperature control may be used in which the amount of hot water flowing into the heater 6 is adjusted to adjust the temperature of the air blown into the vehicle interior.

Further, in the second dehumidifying and heating mode, the refrigerant compressor 20 → the brine refrigerant heat exchanger 7 or the condenser 71
The refrigeration cycle may be changed so that the first decompression means 21 → the outdoor heat exchanger 23 → the evaporator 24 → the refrigerant compressor 20 can form a dehumidifying and heating cycle in which the refrigerant circulates. That is, in the second dehumidifying and heating mode, the refrigeration cycle may be changed so that a dehumidifying and heating cycle in which the outdoor heat exchanger 23 and the evaporator 24 are operated in series as an evaporator can be formed.

Then, to the brine cycle shown in FIG. 1, a radiator such as a radiator, an auxiliary heater such as an exhaust gas collector for collecting exhaust heat of an electric appliance, an electric heater, and an auxiliary device such as a flow path switching valve are added. You may. Further, as the pressure reducing means, a pressure reducing means such as an automatic temperature expansion valve, an electric expansion valve, or an orifice may be used. However, it is desirable to use an inexpensive and trouble-free fixed throttle such as a capillary tube or an orifice. Then, a receiver (liquid receiver) may be used as the gas-liquid separator. The connection point of this receiver is
It is connected between the brine refrigerant heat exchanger 7 and the first decompression means 21 or the outdoor heat exchanger 23 and the second decompression means 2
2

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an overall configuration of an air conditioner for an electric vehicle (first embodiment).

FIG. 2 is a block diagram showing a control system of the air conditioner for an electric vehicle (first embodiment).

FIG. 3 is a front view showing an operation panel (first embodiment).

FIG. 4 is a flowchart showing main control processing by an ECU (first embodiment).

FIG. 5 is a subroutine showing an air-conditioning operation mode determination control (first embodiment).

FIG. 6 is a subroutine showing blow-out temperature control during DEF control (first embodiment).

FIG. 7A is a characteristic diagram showing selection conditions of a dehumidifying heating mode and a dehumidifying cooling mode, and FIG. 7B is a characteristic diagram showing selection conditions of a dehumidifying cooling mode and an outside air cooling mode (first).
Embodiment).

FIG. 8 is a schematic diagram illustrating an overall configuration of an air conditioner for an electric vehicle (second embodiment).

[Explanation of symbols]

Reference Signs List 1 air conditioner unit 2 air conditioning duct 6 hot water heater (heating indoor heat exchanger, first indoor heat exchanger) 7 brine refrigerant heat exchanger (heating indoor heat exchanger, refrigerant heat medium heat exchanger) 8 water pump Heat medium circulation means) 10 ECU (air conditioning control device, target outlet temperature determination means,
Suction temperature detecting means) 20 Refrigerant compressor 21 First depressurizing means 22 Second depressurizing means 23 Outdoor heat exchanger 24 Evaporator (Cooling indoor heat exchanger, Second indoor heat exchanger) 41 Internal air temperature sensor (Indoor air temperature detecting means) 42 outside air temperature sensor (outside air temperature detection means) 45 post-evaporation temperature sensor (evaporator temperature detection means) 50 operation panel 51 temperature setting switch (blowing temperature setting means) 58 DEF switch (dehumidification mode setting means) 71 condenser (for heating) Indoor heat exchanger, first indoor heat exchanger) VC solenoid valve (circulation circuit switching means) VH solenoid valve (circulation circuit switching means) VD solenoid valve (circulation circuit switching means)

Claims (6)

[Claims] (A) a duct for sending air into a vehicle compartment; (b) a blower for blowing air into the vehicle compartment in the duct; and (c) heating a refrigerant discharged from a refrigerant compressor. A circulation circuit for a dehumidifying / cooling mode which flows in the order of the indoor heat exchanger for use, the outdoor heat exchanger, the pressure reducing means, and the indoor heat exchanger for cooling and returns to the refrigerant compressor; and (d) refrigerant discharged from the refrigerant compressor. A circulation circuit for a dehumidifying and heating mode, which flows in the order of the heating indoor heat exchanger, the decompression means, the outdoor heat exchanger or the cooling indoor heat exchanger and returns the refrigerant to the refrigerant compressor; A circulation circuit switching means for switching to one of the cooling circuit circulation circuit and the dehumidification / heating mode circulation circuit; (f) a dehumidification mode setting means for dehumidifying the vehicle interior; and (g) blowing into the vehicle interior. Blowing air (H) an inside air temperature detecting means for detecting an inside air temperature, an outside air temperature detecting means for detecting an outside air temperature, and a setting air temperature set by the blowing temperature setting means. A target air temperature determining means for determining a target air temperature of air to be blown into a vehicle cabin based on an inside air temperature detected by the inside air temperature detecting means and an outside air temperature detected by the outside air temperature detecting means; and A suction temperature detecting means for detecting a suction temperature of the air sucked into the heat exchanger; and when the dehumidification in the vehicle compartment is desired by the dehumidification mode setting means, the target blow temperature determined by the target blow temperature determining means. But,
When the temperature is lower than the suction temperature detected by the suction temperature detection means, the circulation circuit switching means is controlled so as to switch to the dehumidifying cooling mode circulation circuit, and the target outlet temperature determined by the target outlet temperature determination means is ,
An air conditioner for a vehicle, comprising: an air conditioning controller that controls the circulation circuit switching means to switch to the dehumidifying and heating mode circulation circuit when the temperature is higher than the suction temperature detected by the suction temperature detection means. 2. The vehicle air conditioner according to claim 1, wherein the refrigerant compressor is an electric refrigerant compressor that is rotationally driven by a drive motor that is energized and controlled by an inverter as a drive power supply. An air conditioner for a vehicle, comprising: 3. The air conditioner for a vehicle according to claim 2, wherein the indoor heat exchanger for heating is disposed in the duct.
The first indoor heat exchanger that is operated as a condenser that condenses the refrigerant by exchanging heat between the refrigerant discharged from the refrigerant compressor and air in the duct, wherein the indoor heat exchanger is a duct. Is disposed upstream of the first indoor heat exchanger in the air flow direction,
An air conditioner for a vehicle, wherein the second indoor heat exchanger is operated as an evaporator for evaporating a refrigerant flowing from the decompression means. 4. The vehicle air conditioner according to claim 2, wherein the heating indoor heat exchanger is disposed outside the duct.
A refrigerant heat medium heat exchanger operated as a condenser that condenses the refrigerant by exchanging heat between the refrigerant and the heat medium discharged from the refrigerant compressor, the refrigerant heat medium heat exchanger disposed in the duct, A first indoor heat exchanger that heats the air in the duct with a more inflowing heat medium, and a heat medium circulating unit that circulates a heat medium between the refrigerant heat medium heat exchanger and the first indoor heat exchanger The cooling indoor heat exchanger is disposed in the duct at an upstream side of the first indoor heat exchanger in the air flow direction, and evaporates the refrigerant flowing from the pressure reducing means. An air conditioner for a vehicle, wherein the second air conditioner is operated as a second indoor heat exchanger. 5. The vehicle air conditioner according to claim 4, further comprising: a heating amount adjusting unit that adjusts a heating amount of air in the duct by a heat medium flowing in the first indoor heat exchanger. The air-conditioning control device has evaporator temperature detecting means for detecting the temperature of the second indoor heat exchanger, and the target outlet temperature determining means when the refrigeration cycle is switched to the dehumidifying cooling mode circulation circuit. Controlling the heating amount adjusting means based on the target blow-out temperature determined in the above and the temperature of the second indoor heat exchanger detected by the evaporator temperature detecting means; An air conditioner for a vehicle, wherein the rotation speed of the refrigerant compressor is controlled such that the temperature of the two indoor heat exchangers reaches a target temperature. 6. The air conditioner for a vehicle according to claim 5, wherein the air conditioning controller is configured to control the duct by the heating amount adjusting means when the refrigeration cycle is switched to the dehumidifying / cooling mode circulation circuit. When the heating amount of the air in the air falls below a predetermined value, the operation of the heat medium circulating means is stopped, and the target blowing temperature determined by the target blowing temperature determining means and detected by the evaporator temperature detecting means. An air conditioner for a vehicle, wherein the rotation speed of the refrigerant compressor is controlled so that the temperature of the second indoor heat exchanger substantially matches the temperature of the second indoor heat exchanger.