JPH10258632A - Vehicular airconditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the airconditioning unit for an electric car which can continue the dehumidifying with a little heating in a cabin, while preventing the frosting of an evaporator by optimizing the selection condition of a defumidity heating mode and an outer air heating mode when an occupant hopes the dehumidification heating in the cabin. SOLUTION: When DEF(defroster) switch is pushed as the defumidity heating mode in which an outer cabin heat exchanger 23 and an evaporator 24 are operated in parallel is not switched to an outer air heating mode for operating the outer cabin heat exchanger 23 separately as the evaporator as long as the temperature after evaporation is not lowered than the frosting limit temperature (for example, 2 deg.C) of the evaporator 24, in comparison with a conventional airconditioning unit setting a switch condition in response to an outer air temperature, the cabin can be dehumidified with a little heating to remove the cloud of a front window glass until the limit in which the evaporator 24 is frosted.

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 for heating and dehumidifying 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 an electric vehicle fixes the air inlet mode to the outside air introduction mode and the air outlet mode to the defroster mode when it is necessary to dehumidify the interior of the vehicle (especially to remove the fogging of the windshield). By changing the refrigerant path of the air conditioner, the air conditioner is switched to an air conditioning operation mode of a dehumidifying heating mode in which the cooling indoor heat exchanger is operated alone as an evaporator or an outdoor air heating mode in which the outdoor heat exchanger is operated as an evaporator. Try to remove the fogging of the windshield.

[0003] In the dehumidifying and heating mode, the refrigerant discharged from the discharge port of the refrigerant compressor circulates in the order of a heating indoor heat exchanger → a decompression means → a cooling indoor heat exchanger → a refrigerant compressor ( Dehumidification cycle). In the outside air heating mode, the refrigerant discharged from the discharge port of the refrigerant compressor circulates in the order of a heating indoor heat exchanger → a decompression unit → an outdoor heat exchanger → a refrigerant compressor (heating cycle).

[0004] In the above-described air conditioner for an electric vehicle, even when it is necessary to dehumidify the cabin, in order to prevent frost (frost) on the cooling indoor heat exchanger,
The switching condition (selection condition) between the dehumidifying heating mode and the outside air heating mode is only the outside air temperature. That is, when the outside air temperature is a high temperature equal to or higher than the switching temperature (for example, 8 ° C.), to give priority to dehumidification over prevention of frost, the dehumidifying heating mode is selected to heat and dehumidify the vehicle interior, and the outside air temperature becomes the switching temperature (for example, When the temperature is lower than 8 ° C.), the outside air heating mode is selected to heat the vehicle interior in order to prevent frost rather than dehumidification.

[0005]

However, in the air conditioner for an electric vehicle described above, since the dehumidifying heating mode and the outside air heating mode are switched based on the outside air temperature, the windshield or the side glass is temporarily fogged. Therefore, even when the occupant presses the defroster switch to remove the fogging, when the outside air temperature is about 0 ° C to 7 ° C,
Since the outside air heating mode is selected as the dehumidification mode, the air blown into the vehicle compartment is not dehumidified, and a problem arises that the fogging of the front window glass and the side window glass cannot be quickly removed.

[0006] In the case of an air conditioner for an electric vehicle, an electric refrigerant compressor is used. Therefore, the rotational speed of the refrigerant compressor is determined by the temperature of the indoor heat exchanger for cooling. By maintaining the temperature (for example, 3 ° C.) and performing TAO control so that the temperature of the air blown out into the vehicle interior becomes the target blow-out temperature TAO, if the outside air temperature is about 3 ° C. to 7 ° C., the air conditioner switches from the dehumidifying heating mode to the outside air temperature. It is thought that the heating mode dehumidification inside the vehicle compartment can be continued without switching to the heating mode, but such control has not been performed.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to optimize the selection of a dehumidifying heating mode and an outside air heating mode when an occupant desires dehumidification in a vehicle cabin, thereby enabling the cooling indoor heat exchanger to be mounted. It is an object of the present invention to provide a vehicle air conditioner that can continue heating and dehumidifying in a vehicle compartment while preventing frost.

[0008]

According to the first aspect of the present invention, when the dehumidification of the vehicle interior is desired, the temperature of the cooling indoor heat exchanger is changed to the frost of the cooling indoor heat exchanger. As long as the temperature does not drop below the limit temperature, the circuit is not switched to the outside air heating mode circulation circuit, and is maintained in the dehumidification heating mode circulation circuit. Thereby, the refrigerant discharged from the refrigerant compressor is:
Heating heat exchanger, decompression means, by flowing through the cooling indoor heat exchanger and sucked into the refrigerant compressor, compared with those that select between the dehumidifying heating mode and the outside air heating mode according to the outside air temperature, Up to the limit at which the cooling indoor heat exchanger becomes frosted, it is possible to continue the heating dehumidification in the vehicle interior, for example, to remove the fogging of the windshield.

According to the second aspect of the present invention, when the temperature of the cooling indoor heat exchanger is equal to or higher than the first predetermined temperature which is higher than the frost limit temperature when dehumidification of the vehicle interior is desired. Is switched to the first dehumidifying and heating mode circulation circuit. Thereby, the refrigerant discharged from the refrigerant compressor is:
By flowing through the heating heat exchanger, the decompression means, and the cooling indoor heat exchanger and being sucked into the refrigerant compressor, the interior of the vehicle is heated and dehumidified. When the temperature of the cooling indoor heat exchanger is equal to or higher than a second predetermined temperature lower than the frost formation limit temperature,
It is switched to the circulation circuit for outside air heating mode. As a result, the refrigerant discharged from the refrigerant compressor flows through the heating heat exchanger, the decompression means, and the outdoor heat exchanger and is sucked into the refrigerant compressor, thereby heating the outside of the vehicle.

When the temperature of the cooling indoor heat exchanger is between the first predetermined temperature and the second predetermined temperature, the cooling indoor heat exchanger is switched to the second dehumidifying and heating mode circulation circuit. Thereby, the refrigerant discharged from the refrigerant compressor flows through the heating heat exchanger, the decompression means, the outdoor heat exchanger, and the indoor cooling heat exchanger, and is sucked into the refrigerant compressor, thereby heating the vehicle interior. It is slightly dehumidified. In the circulation circuit for the second dehumidifying and heating mode, the indoor heat exchanger for cooling and the outdoor heat exchanger are operated in parallel or in series to operate as an evaporator.
Compared to the case where the first dehumidifying and heating mode circulation circuit in which the cooling indoor heat exchanger is operated independently as the evaporator is used, the heat pump capacity (heating capacity) is equal to the amount of the refrigerant absorbing heat from the air outside the duct in the outdoor heat exchanger. ) Will be higher. For this reason, for example, even if the outside air temperature sucked into the cooling indoor heat exchanger is a low outside air temperature, the target outlet temperature can be created while maintaining the temperature of the cooling indoor heat exchanger at the frost formation limit temperature.

According to the third aspect of the present invention, an electric vehicle having no engine cooling water or an air-cooled type is used, for example, by using an electric-type refrigerant compressor rotated and driven by a drive motor as the refrigerant compressor. 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 blowout temperature of the air blown into the vehicle compartment can be made to substantially match the target blowout temperature.

According to the fourth aspect of the present invention, when the circuit is switched to the dehumidifying and heating mode circulation circuit by the circulation circuit switching means, the air sucked into the duct is cooled by the refrigerant flowing into the second indoor heat exchanger. After being cooled and dehumidified by the heat of vaporization, the refrigerant is reheated by the heat of condensation of the refrigerant flowing into the first indoor heat exchanger, thereby heating and dehumidifying the vehicle interior. Further, when the circuit is switched to the outside air heating mode circulation circuit by the circulation circuit switching means, the air sucked into the duct is heated by the condensation heat of the refrigerant flowing into the first indoor heat exchanger, and the inside of the vehicle interior is heated by the outside air. I do.

According to the fifth aspect of the present invention, while maintaining the temperature of the second indoor heat exchanger detected by the evaporator temperature detecting means at the frost limit temperature, the target blow temperature determined by the target blow temperature determining means. By controlling the rotation speed of the refrigerant compressor in accordance with the target blowing temperature determined by the target blowing temperature determining means, even if the operation is continued by the dehumidifying and heating mode circulation circuit, the cooling indoor heat exchanger Frost can be prevented. For this reason, it is possible to continue the heating dehumidification in the vehicle cabin.

According to the sixth aspect of the present invention, when the circuit is switched to the dehumidifying and heating mode circulation circuit by the circulation circuit switching means, the air sucked into the duct is cooled by the refrigerant flowing into the second indoor heat exchanger. After being cooled and dehumidified by the heat of evaporation of the vehicle, it is reheated by the heat medium flowing into the first indoor heat exchanger to heat and dehumidify the vehicle interior. When the circuit is switched to the outside air heating mode circulation circuit by the circulation circuit switching means, the air sucked into the duct is heated by the heat medium flowing into the first indoor heat exchanger to heat the outside of the vehicle compartment.

According to the seventh aspect of the present invention, while the temperature of the second indoor heat exchanger detected by the evaporator temperature detecting means is kept at the frosting limit temperature, the target blowing temperature determined by the target blowing temperature determining means. By controlling the rotation speed of the refrigerant compressor in accordance with the target heat medium temperature determined by the target heat medium temperature determining means, even if the operation is continued by the dehumidifying and heating mode circulation circuit, the cooling indoor heat The frost on the exchanger can be prevented. For this reason, it is possible to continue the heating dehumidification in the vehicle cabin.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

[Configuration of First Embodiment] FIGS. 1 to 7 show a first embodiment of the present invention.
FIG. 1 is a view illustrating an overall configuration of an air conditioner for an electric vehicle, and FIG. 2 is a view illustrating a control system of the air conditioner for an electric vehicle.

The 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 the interior of an electric vehicle (vehicle) equipped with a motor M for traveling. EC
(Referred to as U).

The air conditioner unit 1 has an air conditioning duct 2 for forming an air passage for guiding 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 type heater 6, a brine refrigerant heat exchanger 7, a water pump 8, a combustion type heater 9, and a hot water pipe (brine pipe) for connecting these annularly. 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 type heater 6 corresponds 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 when 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 refrigeration 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 this embodiment includes a cooling mode for cooling the vehicle interior, a heating mode for heating the vehicle interior only with a heat pump (heat pump), and a combustion heating mode for heating the vehicle interior only with the combustion heater 9. Etc. 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 electric refrigerant compressor (compressor) that compresses 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 parts 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 therein 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 a cooling indoor heat exchanger and a second indoor heat exchanger of the present invention, and is installed downstream (downwind) of the hot water heater 6 in the air conditioning duct 2. In the cooling mode and the dehumidifying mode (first dehumidifying / heating mode, dehumidifying / cooling mode, outside air cooling mode), the low-temperature / low-pressure refrigerant decompressed by the second decompression means 22 and the first decompression means 21 is heated by the air in the air conditioning duct 2. It is operated as an evaporator for evaporating by exchange. 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 operated as a gas-liquid separator that stores the liquid refrigerant by gas-liquid separation of the refrigerant flowing into the liquid refrigerant and the gas refrigerant, and supplies only the gas refrigerant to the refrigerant compressor 20.

The circulation 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 dehumidification cycle is the circulation circuit for dehumidification and heating mode of the present invention,
It corresponds to a circulation circuit for the dehumidifying and heating mode. The dehumidifying and heating cycle includes the dehumidifying and heating mode circulation circuit of the present invention,
It corresponds to a circulation circuit for the dehumidifying and heating mode. Further, the heating cycle corresponds to the outside air heating mode circulation circuit of the present invention. In the present embodiment, the circulation circuit switching means opens when energized (ON, ON), and stops energization (OFF,
Three solenoid on-off valves (hereinafter abbreviated as solenoid valves) VC, VH, and VD that are closed when turned off) 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 sequentially to 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 an air-conditioning control device and a target outlet temperature determining means of the present invention, and includes a central processing unit (hereinafter referred to as a CPU) 31, a ROM 32, and a RAM 3.
3. It has an A / D converter 34, interfaces 35 and 36, etc., and is itself known. ECU1
No. 0 is operated when electric power is supplied from a vehicle-mounted power supply V via a junction box J which is also 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 comprises 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 composed of, for example, 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 for setting the suction port mode to the inside air circulation mode by controlling the opening / 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. Instead of the DEF switch 58, a dehumidification mode setting means such as a dehumidification switch or an anti-fog sensor for detecting fogging of the windshield may be provided.

[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 TA detected by the outside air temperature sensor 42.
M, insolation TS detected by the insolation sensor 43, post-evaporation temperature TE detected by the post-evaporation temperature sensor 45, water temperature sensor 46
Each sensor signal is read from various sensors such as the hot water temperature TW detected in (inside air temperature detection means, outside air temperature detection means,
Evaporator temperature detecting means: Step S4). Then, R
The target blowing temperature TAO of the air blown into the passenger compartment of the electric vehicle is calculated based on the following equation 1 stored in the OM 32 (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, a subroutine shown in FIG. 5 is called, and the air-conditioning operation mode is determined according to the target air temperature TAO calculated in step S5 of the flowchart in FIG. 4 and the outside air temperature TAM detected by the outside air temperature sensor 42. (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 the present embodiment 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, the air-conditioning operation mode corresponding to the target blow-out 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 is selected (step S22). Thereafter, the process exits the subroutine of FIG.

If the result of the determination in step S31 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 S23). Here, at the time of the DEF control, since the suction port mode is the 100% outside air introduction mode, the outside air temperature TA is set as the suction temperature Tin.
Use M. Subsequently, 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 of FIG. 4 is selected (step S5).
24). Thereafter, the process exits the subroutine of FIG.

Here, when the DEF switch 58 of the operation panel 50 is pressed, the ECU 10 performs the DEF control shown in Table 1 below. Table 1 shows the operating state of each air conditioner (actuator) under DEF control.

[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 represented by the following equation (2) or equation (3) 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.), the equation of Equation 2 is adopted and (TAM-15 ° C.)
(° C.) is lower than (3 ° C.), the equation of Equation 3 is adopted.

[Equation 2] TAO ≦ TAM-15 ° C.

[Equation 3] TAO ≦ 3 ° C.

When the relationship shown in the following equation (4) is satisfied, the dehumidifying cooling mode in which the water pump 8 is turned on and the refrigeration cycle is switched to the cooling cycle is set as shown in Table 1. select.

## EQU4 ## TAM-15 ° C. <TAO ≦ Tin

When the relationship expressed by the following equation (5) is satisfied, as shown in Table 1, the dehumidifying heating mode in which the water pump 8 is turned on and the refrigeration cycle is switched to the dehumidification cycle. select.

[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
The rotation speed of the refrigerant compressor 20 is adjusted such that the actual blow temperature TA blown into the vehicle interior becomes the target blow temperature TAO while maintaining the freezing limit temperature (frost formation limit temperature, for example, 2 ° C.).
Control is performed according to the temperature deviation between the target hot water temperature TWO 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 operation of each actuator during the DEF control by the ECU 10 of the present embodiment will be described with reference to FIGS.

(External Air Cooling Mode) When the occupant presses the DEF switch 58 and desires to remove the fogging of the windshield, if the outdoor air cooling mode is selected as the air conditioning operation mode, the water pump 8 is turned off and the refrigerant is turned off. The compressor 20 is turned on and the two A / M dampers 19 are MAXC
OOL, the solenoid valve VC is turned on, and the solenoid valve V
H 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 outside air sucked into the air-conditioning duct 2 from the outside air suction port 4 is cooled and dehumidified when passing through the evaporator 24 to become low-humidity air.
The air is blown out from the DEF outlet 11 toward the inner surface of the windshield. 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.

(Dehumidifying / Cooling Mode) When the occupant presses the DEF switch 58 and desires to remove the fogging of the windshield, if the dehumidifying / cooling mode is selected as the air conditioning operation mode, the water pump 8 and the refrigerant compressor 20 are operated. Is turned on, 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.
OOL, 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 outside air sucked into the air conditioning duct 2 from the outside air suction port 4 is cooled and dehumidified when passing through the evaporator 24 to become low humidity air. And the evaporator 24
Is passed through the hot water heater 6 in accordance with the opening degree of the A / M damper 19, is reheated, and 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.

(Dehumidifying and Heating Mode) When the occupant presses the DEF switch 58 to remove the fogging of the windshield and the dehumidifying and heating mode is selected as the air-conditioning operation mode, the water pump 8 and the refrigerant compressor 20 are operated. Is turned on, 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 When the post-evaporation temperature TE is equal to or higher than a first predetermined temperature (for example, 2.5 ° C.) higher than the freezing limit temperature (for example, 2 ° C.),
As shown in the characteristic diagram of FIG. 7, when the solenoid valve VH is turned off and the solenoid valve VD is turned on, the first dehumidifying heating mode in which the evaporator 24 operates independently as an evaporator is set. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the dehumidification cycle (in the direction of arrow D), and the brine refrigerant heat exchanger 7 → the first pressure reducing means 21 → the solenoid valve VD → the evaporator 24 → the accumulator 25 → the refrigerant Circulates like compressor 20. 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.), the characteristic shown in FIG. As shown in the figure, when both the solenoid valves VH and VD are turned on, the outdoor heat exchanger 23 and the evaporator 2 are turned on.
4 is set in the second dehumidifying and heating mode in which it operates as an evaporator in parallel. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the dehumidifying and heating cycle (the path indicated by arrows H and D in FIG. 1) and passes through the brine refrigerant heat exchanger 7 → the first pressure reducing means 21. Later, 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 second dehumidifying and heating mode, the outdoor heat exchanger 23 is operated in parallel with the evaporator 24 as an evaporator. 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) Outside air heating mode When the post-evaporation temperature TE is equal to or lower than a second predetermined temperature (for example, 1.5 ° C.) lower than the freezing limit temperature (for example, 2 ° C.),
When the solenoid valve VH is turned on and the solenoid valve VD is turned off, the outside air heating mode in which the outdoor heat exchanger 23 operates alone as an evaporator is set. Therefore, the refrigerant discharged from the discharge port of the refrigerant compressor 20 flows through the heating cycle (the direction of the arrow H), and the brine refrigerant heat exchanger 7 → first
It circulates as pressure reducing means 21 → outdoor heat exchanger 23 → solenoid valve VH → 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 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.

[Effects of the First Embodiment] As described above, in the present embodiment, in order to remove the fogging of the windshield, when the occupant desires the dehumidifying heating mode, the initial stage of the DEF control in the dehumidifying heating mode is performed. When the outside air temperature TAM is equal to or higher than 8 ° C. in the step, the post-evaporation temperature TE is equal to or higher than 8 ° C., and the first dehumidifying and heating mode is selected. At this time, in the air conditioner unit 1, the rotation speed of the refrigerant compressor 20 is adjusted to the target hot water temperature TW such that the post-evaporation temperature TE is kept at the freezing limit temperature (for example, 2 ° C.) so that the target blowing temperature TAO is reached.
By controlling according to O, the temperature TE after evaporation is 2 ° C.
Down to As a result, the temperature TE after the evaporation becomes 2.5 ° C.
If the temperature falls below, the second dehumidifying and heating mode is selected.

When the outside air temperature TAM is 5 ° C. to 8 ° C. at the initial stage of the DEF control in the dehumidifying and heating mode,
While maintaining the post-evaporation temperature TE at 2 ° C., the target blowing temperature TA
Even if the rotational speed of the refrigerant compressor 20 is controlled in accordance with the target hot water temperature TWO so as to be O, the evaporator 2
4, the amount of heat absorbed by the refrigerant is small, so that the hot water heater 6 cannot obtain a sufficient reheat amount, and the target outlet temperature TA
O cannot be obtained. Therefore, the post-evaporation temperature TE tends to drop below 2 ° C., but when the post-evaporation temperature TE drops below 2.5 ° C., the outdoor heat exchange mode is selected by selecting the second dehumidifying heating mode. Since the refrigerant can absorb heat in the heater 23, the target outlet temperature TAO can be produced while maintaining the post-evaporation temperature TE at 2 ° C.

When the outside air temperature TAM sucked into the evaporator 24 is 2 ° C. to 5 ° C., the temperature is temporarily cooled and dehumidified by the evaporator 24, and then reheated (reheated) by the hot water heater 6 to set the target outlet temperature TAO. Since it is difficult to obtain, in this case, there is a possibility that the post-evaporation temperature TE falls below 2 ° C. and the evaporator 24 frosts. Therefore, in the present embodiment, the post-evaporation temperature TE is 1.5
When the temperature has dropped below the temperature of ℃, the second dehumidifying and heating mode is switched to the outside air heating mode to perform dehumidification by introducing low-humidity outside air, thereby preventing frost of the evaporator 24.

Therefore, while maintaining the post-evaporation temperature TE at the freezing limit temperature, the rotation speed of the refrigerant compressor 20 is controlled in accordance with the target hot water temperature TWO so as to reach the target blow-out temperature TAO. Since the first dehumidification heating mode or the second dehumidification heating mode is continued until the limit at which the evaporator 24 becomes frosted, as compared with the selection between the dehumidification heating mode and the outside air heating mode, the evaporator 24 does not switch to the outside air heating mode. Removal of fogging on the windshield can be continued. That is, the evaporator 2
4. Dehumidification can be performed continuously while suppressing frost (freezing).

The temperature of the air blown out from the DEF air outlet 11 is the target air temperature TAO obtained by the equation (1) in consideration of the set air temperature Tset, the inside air temperature TR, the outside air temperature TAM, the amount of solar radiation TS, and the like. So that
Since the rotation speed of the refrigerant compressor 20 is controlled (TWO control) in accordance with the target hot water temperature TWO, the air conditioning control method for an engine-equipped auto air conditioner can be applied to this electric vehicle air conditioner. .

Further, by using an electrically driven refrigerant compressor as the refrigerant compressor 20 and controlling the energization of the refrigerant compressor 20 by an air conditioner inverter 30 as a driving power supply, the refrigerant discharged from the refrigerant compressor 20 is controlled. The discharge amount can be changed, that is, the reheat amount in the hot water heater 6 and the cooling amount in the evaporator 24 can be easily adjusted. Therefore, only by changing the rotation speed of the refrigerant compressor 20, the blow-out temperature of the air blown into the vehicle compartment can be made substantially equal to the target blow-out temperature TAO.

[Structure of 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 refrigerant discharged from a discharge port of the refrigerant compressor 20 flows, and a pressure reduction of refrigerant flowing out of the condenser 71. Decompression means comprising first and second decompression means 21 and 22, an outdoor heat exchanger 23 installed outside the air conditioning duct 2, and an air conditioning duct 2
Evaporator 24, an accumulator 25 for gas-liquid separation, a circulation circuit switching means comprising solenoid valves VC, VH, VD for switching the flow direction of the refrigerant in the refrigeration cycle, and a refrigerant pipe for connecting these in a ring form. It is configured.

The condenser 71 corresponds to the heating indoor heat exchanger and the first indoor heat exchanger of the present invention. The condenser 71 is installed downstream of the evaporator 24 in the air conditioning duct 2 and condenses the refrigerant flowing inside. It is a condenser that heats the air passing by heat. The condenser 71 adjusts the amount of air passing through the condenser 71 (the amount of warm 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 cabin. 2
The air mix (A / M) dampers 72 are rotatably supported. These A / M dampers 72 are driven by an actuator (not shown) such as a stepping motor or a servomotor.

Here, in the present embodiment, at the time of the DEF control, a dehumidifying cooling mode in which the refrigeration cycle is operated in a dehumidifying cooling cycle, and a dehumidifying heating mode in which the refrigeration cycle is operated in a dehumidifying cycle, a dehumidifying heating cycle, or a heating cycle. Is selected. In the cooling cycle, the refrigerant discharged from the discharge port of the refrigerant compressor 20 is supplied to the condenser 71.
By providing a refrigerant flow path that can be bypassed and flow directly into the outdoor heat exchanger 23 via the solenoid valve VC, the same operation and effect as in the outdoor air cooling mode in the dehumidification mode of the first embodiment can be obtained. . Also in the present embodiment, when the DEF switch 58 is pressed to dehumidify the vehicle interior (especially removing the fogging of the windshield), the dehumidifying heating mode and the outside air heating mode are set according to the post-evaporation temperature TE. Is selected, the same effect as in the first embodiment can be achieved.

[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 an air-cooled engine or a vehicle equipped with a water-cooled engine. Is also good. In the present embodiment, the DEF switch 58 as the dehumidification mode setting means is pressed to
The control method of the present invention is used only when executing the control (dehumidification mode control). However, the mode setting switch 55 is pressed as the dehumidification mode setting means, and the FOOT mode is set as the outlet mode.
When the mode or the F / D mode is selected, the control method of the present invention may be used.

In the present embodiment, the target blowout temperature TAO is determined based on the set blowout temperature Tset, the inside air temperature TR, the outside air temperature TAM, and the amount of solar radiation TS.
However, the target blowout temperature TAO may be calculated as the target blowout temperature determining means based on the set blowout temperature Tset, the inside air temperature TR, the outside air temperature TAM, and the outside air humidity. Further, the suction temperature of the air sucked into the evaporator 24 may be considered as the target blowing temperature TAO.

In the present embodiment, the post-evaporation temperature sensor 45 for detecting the air temperature immediately after passing through the evaporator 24 is used as the evaporator temperature detection means, but the evaporator (the second indoor heat exchanger) is used as the evaporator temperature detection means. ) A temperature sensor for detecting the surface temperature (fin temperature) of 24 and the evaporation temperature may be used. In the present embodiment, the freezing limit temperature (frost limit temperature) is set to 2 ° C., the first predetermined temperature is set to 2.5 ° C., and the second predetermined temperature is set to 1.5 ° C. The limit temperature is set to any one of 2 ° C. to 4 ° C., and the first predetermined temperature and the second predetermined temperature are set to 0.5 in accordance with the frost formation limit temperature.
The temperature may be changed in the range of ℃ to 1.5 ℃.

In the present 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, the air mix temperature control method of adjusting the opening degree of the A / M damper 19 to adjust the temperature of the air blown into the vehicle compartment in the dehumidifying / cooling mode is used. 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.

In the second dehumidifying and heating mode, the refrigerant compressor 20 → the brine refrigerant heat exchanger 7 or the condenser 7
The refrigeration cycle may be changed so as to form a dehumidifying and heating cycle in which the refrigerant circulates as in 1 → first decompression means 21 → outdoor heat exchanger 23 → evaporator 24 → refrigerant compressor 20. 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 and other heat radiating devices, an auxiliary heater and other auxiliary devices such as an exhaust gas recovery device and an electric heater for recovering exhaust heat from electric appliances, 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. 7 is a characteristic diagram showing a selection condition between a dehumidifying heating mode and an outside air heating 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,
(Target heat medium temperature determining means) 20 Refrigerant compressor 21 First decompression means 22 Second decompression means 23 Outdoor heat exchanger 24 Evaporator (Cooling indoor heat exchanger, Second indoor heat exchanger) 41 Inside air temperature sensor (Inside air temperature) Detection 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 capacitor ( 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 (7)

[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 and heating mode, which flows in the order of an indoor heat exchanger for use, a decompression means, and an indoor heat exchanger for cooling and returns to the refrigerant compressor; and (d) the refrigerant discharged from the refrigerant compressor is supplied to the heating room. (E) at least a circulation circuit for the outside air heating mode or a circulation circuit for the outside air heating mode which flows in the order of the heat exchanger, the pressure reducing means, and the outdoor heat exchanger and returns to the refrigerant compressor; A circulation circuit switching means for switching to any one of the circulation circuits; (f) a dehumidification mode setting means for desiring dehumidification in the vehicle interior; and (g) an evaporator temperature detection means for detecting a temperature of the cooling indoor heat exchanger. (H) the above When dehumidification of the vehicle interior is desired by the dehumidification mode setting means, the temperature of the cooling indoor heat exchanger detected by the evaporator temperature detecting means is equal to or higher than the frost limit temperature of the cooling indoor heat exchanger. In the case, the circulation circuit switching means is controlled to switch to the circulation circuit for the dehumidifying and heating mode, and the temperature of the cooling indoor heat exchanger detected by the evaporator temperature detection means is lower than the frost formation limit temperature. In this case, an air conditioner for a vehicle, comprising: an air conditioning controller that controls the circulation circuit switching means so as to switch to the outside air heating mode circulation circuit. 2. The air conditioner for a vehicle according to claim 1, wherein the circulation circuit for dehumidifying and heating mode is a first circulation circuit for dehumidifying and heating mode in which the cooling indoor heat exchanger is operated independently as an evaporator. And a second dehumidifying and heating mode circulation circuit in which the outdoor heat exchanger and the cooling indoor heat exchanger are operated in parallel or in series as an evaporator, and the air conditioning control device is configured by the dehumidification mode setting means. When dehumidification of the vehicle interior is desired, when the temperature of the cooling indoor heat exchanger detected by the evaporator temperature detecting means is equal to or higher than a first predetermined temperature higher than the frost formation limit temperature, (1) controlling the circulation circuit switching means so as to switch to the circulation circuit for dehumidification and heating mode, wherein the temperature of the cooling indoor heat exchanger detected by the evaporator temperature detection means is lower than the frosting limit temperature; Place If the temperature is equal to or lower than the constant temperature, the circulation circuit switching means is controlled to switch to the outside air heating mode circulation circuit, and the temperature of the cooling indoor heat exchanger detected by the evaporator temperature detection means is equal to the first predetermined temperature. An air conditioner for a vehicle, comprising: controlling the circulation circuit switching means to switch to the second dehumidifying and heating mode circulation circuit when the temperature is between the temperature and the second predetermined temperature. 3. An electric air conditioner for a vehicle according to claim 1, wherein said refrigerant compressor is rotationally driven by a drive motor which is energized and controlled by an inverter as a drive power supply. An air conditioner for a vehicle, which is an air conditioner. 4. The air conditioner for a vehicle according to claim 3, wherein the indoor heat exchanger for heating is disposed in the duct.
The first indoor heat exchanger that is operated as a condenser that exchanges heat between the refrigerant discharged from the refrigerant compressor and air in the duct to condense the refrigerant, wherein the indoor heat exchanger for cooling is: A second indoor heat exchanger that is disposed upstream of the first indoor heat exchanger in the direction of air flow in the duct and that operates as an evaporator that evaporates the refrigerant that has flowed in from the decompression means. An air conditioner for a vehicle, comprising: 5. An air conditioner for a vehicle according to claim 4, wherein said air conditioning control device sets an outlet temperature of air to be blown into a vehicle interior to a desired outlet temperature, and the outlet temperature setting device. Means for determining a target blow-off temperature of the air blown into the vehicle cabin based on the set blow-out temperature set by the means, and a temperature of the second indoor heat exchanger detected by the evaporator temperature detecting means. Controlling the rotation speed of the refrigerant compressor in accordance with the target blowing temperature determined by the target blowing temperature determining means so that the target blowing temperature is determined by the target blowing temperature determining means while maintaining the frosting limit temperature. An air conditioner for a vehicle, comprising: 6. The air conditioner for a vehicle according to claim 3, wherein the indoor heat exchanger for heating 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. 7. An air conditioner for a vehicle according to claim 6, wherein said air conditioning control device sets an outlet temperature of air to be blown into a vehicle interior to a desired outlet temperature, and the outlet temperature setting device. Means for determining a target blow-off temperature of air blown into the vehicle cabin based on the set blow-out temperature set by the means, and a target heat medium temperature based on the target blow-off temperature determined by the target blow-off temperature determining means. A target heat medium temperature determining means for determining the temperature of the second indoor heat exchanger detected by the evaporator temperature detecting means at the frost formation limit temperature while maintaining the target blowing temperature determined by the target blowing temperature determining means. An air conditioner for a vehicle, wherein the rotation speed of the refrigerant compressor is controlled according to a target heat medium temperature determined by the target heat medium temperature determining means so as to be a temperature.