JPH06206440A - Heat pump type air-conditioning device for vehicle - Google Patents

Abstract

PURPOSE:To provide a heat pump type air-conditioning device which occupies a small space because of a simple structure, can secure a high heating capacity without requiring a large electric power, and furthermore, being thoughtful consideration in respect to the environmental protection. CONSTITUTION:In a heat pump type air-conditioning device for vehicle to carry out at least the heating by a heat pump, a combustion type heater 35 to heat a coolant is provided, and the system is composed to convert an outdoor heat exchanger 2 and the combustion type heater 35. Such a conversion is carried out according to the outdoor ambient condition, otherwise to the outdoor ambient condition and the temperature in the car room.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for heating a vehicle with a heat pump using a combustion heater.

[0002]

2. Description of the Related Art In a conventional fuel-driven automobile air conditioner, for example, as shown in the specific structure of FIG. 4, a cooling operation is performed by driving a compressor 1 for compressing a refrigerant with an engine to perform outdoor heat exchange. After the heat is radiated to the air outside the vehicle compartment to condense and liquefy the refrigerant by the air conditioner 2 and the outdoor heat exchanger blower 3, the refrigerant is guided to the indoor heat exchanger 5 via the refrigerant expansion device 4, and the indoor blower 6 The air blown by is evaporated while cooling and the cooling action is performed.

The heating action is to stop the compressor 1 and let the engine cooling water (warm water) flow through the heater core 15 to heat the air blown by the indoor blower 6.

The temperature of the air blown from the vehicle interior air outlets 10, 11, 12 is adjusted by adjusting the opening of the mix damper 16 arranged in the ventilation duct 20.
This is performed by adjusting the amounts of warm air flowing through the heater core 15 and cold air bypassing the heater core 15. Further, the compressor 1 is driven by the engine, and the air cooled by the indoor heat exchanger 5 is reheated by the heater core 15, so that dehumidifying and heating can be performed. Further, by using the mix damper 16, it is possible to continuously change the blowout temperature from cooling to heating and vice versa.

On the other hand, a heat pump type air conditioner for driving a compressor by an electric motor, for example, an air conditioner for an electrically driven automobile is shown in FIG.
Shown in. The cooling action is similar to the above, but since there is no cooling water (hot water) for the engine in the heating action, the four-way switching valve 7 is used downstream of the compressor 1 to reverse the refrigerant flow path, and the indoor heat exchanger is used. After heating the air blown by the indoor air blower 6 to condense and liquefy the refrigerant, the refrigerant is guided to the outdoor heat exchanger 2 via the refrigerant expansion device 4, where the air outside the vehicle is cooled. At the same time, heat pump heating is performed in which the refrigerant absorbs heat and evaporates. Therefore, since there is no mix damper like the air conditioner for a fuel-driven automobile, the blow-out temperature is adjusted by controlling the electric motor driving device 9 that drives the electric motor 8 to adjust the rotation speed of the compressor 1. Become. In addition, switching between heating and cooling is performed by the four-way switching valve 7
Is performed by switching the refrigerant flow path.

However, dehumidifying and heating cannot be performed with the heat pump type air conditioner. In addition, since switching between heating and cooling requires switching the refrigerant flow path using a four-way switching valve, it is necessary to smoothly change the outlet temperature from cooling to heating and vice versa. It is difficult. Therefore, as shown in FIG. 6, the above-mentioned problem can be solved by providing the indoor heat exchanger 5 for cooling, providing the second indoor heat exchanger 31 for heating, and further providing the mix damper 16.

[0007]

In heat pump heating in which the refrigerant absorbs and evaporates while cooling the air outside the vehicle compartment using the outdoor heat exchanger, the boiling point of the refrigerant approaches as the vehicle exterior temperature decreases, and When the outdoor heat exchanger is frosted due to low temperature, the heating efficiency is reduced and the electric power consumption of the electric motor that drives the compressor is increased. In the case of an electrically driven vehicle, if the power consumption of the air conditioner becomes large, the power consumption of the vehicle driving electric motor will be suppressed, which will affect the running performance.

Therefore, it is necessary to use the combustion type heater for heating when the vehicle exterior temperature is particularly low.

For example, hot water may be supplied from a combustion heater instead of the engine cooling water shown in FIG. However, in this case, compared to the heat pump type air conditioner of FIG.
A heater core must be installed and hot water piping must be provided inside the vehicle, which complicates the configuration. In addition, since water is used, safety measures are especially necessary when there is a high DC voltage such as in an electrically driven vehicle.

If a heater core is further installed in the heat pump type air conditioner shown in FIG. 6 and hot water piping is provided in the vehicle compartment, a large space is required for the arrangement and the structure becomes extremely complicated.

On the other hand, when using the combustion type heater, generation of carbon dioxide and the like due to combustion must be minimized from the viewpoint of environmental protection.

Therefore, an object of the present invention is to provide a heat pump type air conditioner for a vehicle which has a simple structure, requires a large amount of space and electric power, and has little safety consideration, and has a high heating capacity.

[0013]

In order to solve the above-mentioned problems, a first aspect of the present invention is to provide a heat pump type air conditioner for a vehicle in which at least heating is performed by a heat pump, by providing a combustion type heater for heating a refrigerant. The outdoor heat exchanger and the combustion type heater can be switched.

In order to solve the above-mentioned problems, the present invention provides a heat pump type air conditioner for a vehicle in which at least heating is performed by a heat pump, a combustion type heater for heating a refrigerant is provided, and an outdoor heat exchanger is provided. A means for switching between the combustion type heater and the outdoor heat exchanger and the combustion type heater is provided according to the environmental condition outside the vehicle.

In order to solve the above-mentioned problems, the present invention provides a heat pump type air conditioner for a vehicle in which at least heating is performed by a heat pump, a combustion type heater for heating a refrigerant is provided, and an outdoor heat exchanger is provided. A means for switching between the combustion type heater and the outdoor heat exchanger and the combustion type heater is provided according to the environmental condition outside the vehicle compartment and the temperature inside the vehicle interior.

[0016]

According to the first means of the present invention, since the outdoor heat exchanger and the combustion type heater can be switched, the air outside the vehicle compartment is cooled by using the outdoor heat exchanger in normal heating. While heating the heat pump where the refrigerant absorbs and evaporates, it does not generate carbon dioxide due to combustion.In heating when the outside temperature of the vehicle is particularly low, the outdoor heat exchanger and the combustion type heater are switched to perform combustion type heating. The heating capacity can be secured by controlling the electric power by using a heater.

According to the second means of the present invention, the outdoor heat exchanger and the combustion type heater are switched according to the environmental condition outside the vehicle interior, so the outdoor temperature is low and the outdoor heat exchanger is used. In this case, it can be switched before the heating efficiency drops significantly and consumes a large amount of electric power. Conversely, switching occurs while the vehicle exterior temperature is high and the outdoor heat exchanger is used, but the heating efficiency is still high, causing combustion. It is possible to prevent the generation of carbon dioxide and the like from increasing.

According to the third means of the present invention, the outdoor heat exchanger and the combustion type heater are switched depending on the environmental condition outside the vehicle compartment and the temperature inside the vehicle interior. If the temperature inside the vehicle is stable after heating is started, it is possible to switch from the combustion type heater to the outdoor heat exchanger to reduce the generation of carbon dioxide and the like due to combustion.

[0019]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a vehicle heat pump type air conditioner according to a first embodiment of the present invention. Here, the difference from the configuration diagram of the conventional heat pump type air conditioner for a vehicle shown in FIG. 5 is that in the embodiment of the present invention, the vehicle exterior temperature sensor 21, the vehicle interior temperature sensor 22, The solar radiation amount sensor 23, the first three-way valve 24, the control unit 25, the second three-way valve 26, and the combustion heater 35 are added.

When the outdoor heat exchanger 2 is used for heating, the four-way switching valve 7, the first three-way valve 24, and the second three-way valve 26 are set as shown by the solid line in FIG. The discharged refrigerant is guided to the indoor heat exchanger 5, where the indoor blower 6
After heating the air blown by the refrigerant to condense and liquefy the refrigerant, it is guided to the outdoor heat exchanger 2 via the refrigerant expansion device 4,
The refrigerant absorbs heat and evaporates while cooling the air outside the passenger compartment.

On the other hand, when the combustion type heater 35 is used for heating, the four-way switching valve 7 is set as shown by the solid line in FIG.
The first three-way valve 24 and the second three-way valve 26 are set as shown by the broken line in FIG. The refrigerant absorbs heat and evaporates in the combustion heater 35 and is guided to the indoor heat exchanger 5 in the compressor 1. Here, the air blown by the indoor blower 6 is heated to condense and liquefy the refrigerant and return to the combustion type heater 35 to form a heating cycle.

FIG. 3 shows an operation diagram of heating according to the embodiment of the present invention. The control unit 25 includes a vehicle exterior temperature sensor 21, a vehicle interior temperature sensor 22, and a solar radiation sensor 23.
The temperature outside the vehicle, the temperature inside the vehicle, and the amount of solar radiation are captured as data, and the following judgment and output are performed.

It is judged whether or not the vehicle exterior temperature is above a predetermined value, and if it is above a predetermined value, the combustion type heater 3 as described above.
Since it is not necessary to use No. 5, the first three-way valve 24 and the second three-way valve 26 are set as shown by the solid line in FIG.
To operate with heating.

If the outside temperature of the vehicle is not higher than the predetermined value, it is next determined whether the amount of solar radiation is higher than the predetermined value. If it is higher than the predetermined value, the heating heat load is small and it is not necessary to use the combustion heater 35. Therefore, the first three-way valve 24 and the second three-way valve 26
Is set as shown by the solid line in FIG. 1 and the outdoor heat exchanger 2 is used to operate by heating.

If the amount of solar radiation is not above the predetermined value, it is then determined whether the temperature inside the vehicle is above the predetermined value. If it is above the predetermined value, it is determined that sufficient time has elapsed after the start of heating and the temperature inside the vehicle has risen. I can judge. Since the heating capacity after the vehicle interior temperature has risen may be small, it is not necessary to use the combustion heater 35, and the first three-way valve 24 and the second three-way valve 26 are not shown in FIG.
The solid line is set and the outdoor heat exchanger 2 is used for heating.

If the vehicle interior temperature is not higher than the predetermined value, it can be determined that the time elapsed after the start of heating is short and the heating heat load is large. Therefore, since it is necessary to use the combustion type heater 35, the first three-way valve 24 and the second three-way valve 26 are set as shown by the broken line in FIG. 1, and the combustion type heater 35 is used to operate for heating.

FIG. 2 shows a block diagram of a vehicle heat pump type air conditioner according to a second embodiment of the present invention. Here, the difference from the configuration diagram of the heat pump type air conditioner for a vehicle in which the two refrigeration cycles are provided in FIG. 6 described above is different in the embodiment of the present invention.
Compared to FIG. 6, a vehicle outside temperature sensor 21, a vehicle interior temperature sensor 22, a solar radiation sensor 23, a first three-way valve 24, a control unit 25, a second three-way valve 26, and a combustion heater 35 are added. Is.

As compared with the first embodiment of the present invention, the second embodiment is such that the dehumidifying heating and the outlet temperature are smoothly changed from cooling to heating and vice versa, continuously from heating to cooling. You can

The second indoor heat exchanger 31 is set so that the air blown by the indoor blower 6 is cooled and heated by the indoor heat exchanger 5, and the heating amount is set to the mix damper 16. To adjust.

The operation of switching between the outdoor heat exchanger and the combustion type heater is the same as in the first embodiment of the present invention.

Not limited to this embodiment, the refrigerant may be circulated by a refrigerant pump, or the refrigerant may be circulated by utilizing the pressure change and gravity of the refrigerant without using a compressor or a pump.

Further, with respect to the arrangement, number and configuration of heat exchangers, various applications are possible within the scope of the gist of the present invention.

[0034]

According to the first means of the present invention, since the outdoor heat exchanger and the combustion type heater can be switched, the air outside the vehicle compartment is used by using the outdoor heat exchanger in normal heating. The heat pump heating that the refrigerant absorbs and evaporates while cooling the air does not generate carbon dioxide etc. by combustion,
In heating when the vehicle outside temperature is particularly low, the outdoor heat exchanger and the combustion type heater are switched to each other, and the combustion type heater is used to suppress the electric power to secure the heating capacity.

According to the second means of the present invention, since the outdoor heat exchanger and the combustion type heater are switched according to the environmental condition outside the vehicle interior, the outdoor temperature is low and the outdoor heat exchanger is used. In this case, it can be switched before the heating efficiency drops significantly and consumes a large amount of electric power. Conversely, switching occurs while the vehicle exterior temperature is high and the outdoor heat exchanger is used, but the heating efficiency is still high, causing combustion. It is possible to prevent the generation of carbon dioxide and the like from increasing.

According to the third means of the present invention, the outdoor heat exchanger and the combustion type heater are switched according to the environmental condition outside the vehicle compartment and the temperature inside the vehicle interior, so that the temperature outside the vehicle interior is low. If the temperature inside the vehicle is stable after heating is started, it is possible to switch from the combustion type heater to the outdoor heat exchanger to reduce the generation of carbon dioxide and the like due to combustion.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a vehicle heat pump type air conditioner according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a vehicle heat pump type air conditioner according to a second embodiment of the present invention.

FIG. 3 is a flowchart of heating according to an embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional air-conditioning system for a vehicle driven by a fuel engine.

FIG. 5 is a block diagram of a conventional vehicle heat pump type air conditioner.

FIG. 6 is a configuration diagram of a vehicle heat pump type air conditioner provided with two refrigeration cycles.

[Explanation of symbols]

 2 Outdoor heat exchanger 4 Refrigerant expansion device 5 Indoor heat exchanger 35 Combustion type heater

Claims (3)

[Claims] 1. A heat pump type air conditioner for a vehicle, wherein at least heating is performed by a heat pump, a combustion type heater for heating a refrigerant is provided, and an outdoor heat exchanger and the combustion type heater can be switched. Heat pump air conditioner for vehicles. 2. A heat pump type air conditioner for a vehicle according to claim 1, further comprising means for switching between an outdoor heat exchanger and a combustion type heater according to an environmental condition outside the vehicle. 3. A heat pump type air conditioner for a vehicle according to claim 1, further comprising means for switching between the outdoor heat exchanger and the combustion type heater according to the environmental condition outside the vehicle interior and the temperature inside the vehicle interior.