JP3271347B2 - Heat pump type air conditioner for vehicles - Google Patents

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 by a heat pump using a combustion heater.

[0002]

2. Description of the Related Art A conventional air conditioner for a fuel-driven vehicle, for example, as shown in FIG. 4, has a cooling function in which a compressor 1 for compressing a refrigerant is driven by an engine (not shown) . And the outdoor heat exchanger 2 and the blower 3 for the outdoor heat exchanger
The refrigerant is condensed and liquefied by releasing heat to the air outside the vehicle, and the refrigerant is guided to the indoor heat exchanger 5 via the refrigerant expansion device 4, and evaporated while cooling the air blown by the indoor blower 6. The cooling operation was performed.

In the heating operation, the compressor 1 is stopped, cooling water (warm water) of the engine flows through the heater core 15, and the air blown by the indoor blower 6 is heated.

[0004] The temperature of the air blown out of the vehicle interior air outlets 10, 11 and 12 is adjusted by adjusting the opening of a mix damper 16 arranged in a ventilation duct 20.
This is performed by adjusting the amount of warm air flowing through the heater core and the amount of cool air that bypasses 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 to perform dehumidifying heating. Further, by using the mix damper 16, it is possible to continuously change the blowing 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 electric drive vehicle is shown in FIG.
Shown in The cooling action is the same as above, but for the heating action, there is no cooling water (warm water) of the engine, so the refrigerant flow path is reversed by using a four-way switching valve 7 downstream of the compressor 1 and the indoor heat exchanger After the air blown by the indoor blower 6 is heated at 5 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. While the refrigerant absorbs heat and evaporates, heat pump heating is performed. Therefore, since there is no mix damper as in the air conditioner for a fuel-driven vehicle, the blowout temperature is adjusted by controlling the motor driving device 9 that drives the electric motor 8 to adjust the rotation speed of the compressor 1. Become. Switching between heating and cooling is performed by a four-way switching valve 7.
Is used to switch the refrigerant flow path.

However, the above-mentioned heat pump type air conditioner cannot perform dehumidifying heating. In addition, since it is necessary to switch the refrigerant flow path using a four-way switching valve to switch between heating and cooling, it is necessary to smoothly change the outlet temperature continuously from cooling to heating and vice versa from heating to cooling. It is difficult. Therefore, as shown in FIG. 6, the above 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 heat 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. Heating efficiency is reduced due to the frost formation of the outdoor heat exchanger due to low temperature, and the power consumption of the electric motor driving the compressor is increased. In the case of an electric drive vehicle, if the power consumption of the air conditioner increases, the power consumption of the motor for driving the vehicle is reduced, which affects the driving performance.

[0008] Therefore, it is necessary to use a combustion heater for heating when the temperature outside the vehicle compartment is particularly low.

For example, hot water may be supplied from a combustion heater in place of the engine cooling water in FIG. However, in this case, compared with the heat pump type air conditioner of FIG.
It is necessary to install a heater core and provide hot water piping into the vehicle interior, which complicates the configuration. In addition, since water is used, safety measures are particularly required when there is a high DC voltage, such as in an electric vehicle.

Further, if a heater core is further provided in the heat pump type air conditioner shown in FIG. 6 and hot water piping is provided in the vehicle cabin, a large space is required and the configuration becomes extremely complicated.

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

Accordingly, an object of the present invention is to provide a heat pump type air conditioner for a vehicle having a high heating capacity which has a simple configuration, does not require much space and electric power, and requires less consideration for safety.

[0013]

According to the present invention, as a first means, in order to solve the above-mentioned problems, a combustion type heater for heating a refrigerant is provided in a heat pump type air conditioner for a vehicle which heats at least by a heat pump. Switching between the outdoor heat exchanger and the combustion type heater depends on the outdoor temperature and solar radiation.
Perform based on .

According to the present invention, as a second means, the outside of the vehicle
It switched to the pressurized taste temperature and the amount of solar radiation in addition to vehicle interior temperature
Go ahead.

[0016]

According to the first means of the present invention, the temperature outside the vehicle compartment and the day
The system switches between the outdoor heat exchanger and the combustion heater based on the amount of radiation.
Heating efficiency when using an outdoor heat exchanger is low
Combustion type heating before the power consumption
It can be switched to a heater, and vice versa
If any of the solar radiation is high and an outdoor heat exchanger is used,
Switch to a combustion type heater while the cell efficiency is still high.
To increase the generation of carbon dioxide, etc. due to combustion
Can be prevented.

According to the second aspect of the present invention, the vehicle outside temperature
Outdoor heat exchanger and combustion type according to the amount of solar radiation and vehicle interior temperature
The heater and the heater are switched, so the temperature outside the cabin and the
Even if the heat and solar radiation are both low, the temperature inside the vehicle
If the temperature is high and stable, it can be switched from a combustion heater to an outdoor heat exchanger
To reduce carbon dioxide emissions from combustion
Can be.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 is a block diagram of a vehicle heat pump air conditioner according to a first embodiment of the present invention. Differs from the block diagram of FIG conventional vehicle heat pump type air conditioner of supra Here, embodiments of the present invention, FIG. 5 (not shown) prior than car outdoor temperature sensor as an example, the passenger compartment Temperature sensor (Figure
(Not shown ) , an insolation sensor (not shown) , a first three-way valve 24, a control unit (not shown) , a second three-way valve 26, and a combustion heater 35 are added.

When the heating is performed by using the outdoor heat exchanger 2, 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 the air blown by is heated and the refrigerant is condensed and liquefied, the refrigerant 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 cabin.

On the other hand, when operating by heating using the combustion type heater 35, 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 lines 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, and the refrigerant is condensed and liquefied, and returns to the combustion heater 35 to constitute a heating cycle.

FIG. 3 shows a heating operation diagram 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.
Then, the temperature outside the vehicle compartment, the temperature inside the vehicle compartment, and the amount of solar radiation are fetched as data, and the following judgment and output are performed.

It is determined whether the temperature outside the cabin is equal to or higher than a predetermined value.
5, the first three-way valve 24 and the second three-way valve 26 are set as shown by the solid line in FIG.
Operate with heating using.

If the temperature outside the cabin is not equal to or higher than the predetermined value, it is determined whether or not the amount of solar radiation is equal to or higher than the predetermined value. If the temperature is equal to or higher than the predetermined value, the heating heat load is small and the combustion heater 35 does not need to be used. 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 is operated by heating using the outdoor heat exchanger 2.

If the amount of solar radiation is not equal to or greater than the predetermined value, it is determined whether or not the vehicle interior temperature is equal to or higher than the predetermined value. I can judge. Since the heating capacity after the temperature in the vehicle compartment has risen may be small, it is not necessary to use the combustion type heater 35, and the first three-way valve 24 and the second three-way valve 26 are connected to each other as shown in FIG.
And is operated by heating using the outdoor heat exchanger 2.

If the vehicle interior temperature is not equal to or higher than the predetermined value, it can be determined that the elapsed time 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 broken lines in FIG.

FIG. 2 is a block diagram of a vehicle heat pump air conditioner according to a second embodiment of the present invention. Here, the difference from the configuration diagram of the vehicle heat pump type air conditioner provided with two systems of the refrigeration cycle shown in FIG.
Compared to FIG. 6, a temperature sensor outside the vehicle compartment (not shown ) , a temperature sensor inside the vehicle compartment (not shown) , a solar radiation sensor ( not shown)
) , First three-way valve 24, control unit (illustrated)
Without), the second three-way valve 26, is that the combustion heater 35 is added.

As compared with the first embodiment of the present invention, the second embodiment has a smooth and continuous change of the dehumidifying heating and the outlet temperature from the cooling to the heating and vice versa as described above. Can be.

The air blown by the indoor blower 6 is cooled by the second indoor heat exchanger 31 and heated by the indoor heat exchanger 5, and the heating amount is supplied to the mix damper 16. Adjust.

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

The present invention is 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.

Also, various applications are possible in the arrangement, the number, and the configuration of the heat exchangers, as long as the gist of the present invention is satisfied.

[0034]

According to the first means of the present invention, the temperature outside the vehicle compartment
Depending on the degree and the amount of solar radiation, an outdoor heat exchanger and a combustion heater
Switching between the outside temperature and the amount of solar radiation
Heating efficiency is high when using an outdoor heat exchanger.
Combustion type before power consumption
It can be switched to a heater, and conversely the outside temperature
Indicates the case where any of the solar radiation is high and an outdoor heat exchanger is used.
Switching to a combustion heater while heating efficiency is still high
It will increase the generation of carbon dioxide, etc. due to poor combustion
Evil can be prevented.

According to the second aspect of the present invention, the vehicle exterior temperature
Outdoor heat exchanger and combustion type according to the amount of solar radiation and vehicle interior temperature
The heater and the heater are switched, so the temperature outside the cabin and the
Even if the heat and solar radiation are both low, the temperature inside the vehicle
If the temperature is high and stable, it can be switched from a combustion heater to an outdoor heat exchanger
To reduce carbon dioxide emissions from combustion
Can be.

[Brief description of the drawings]

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

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

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

FIG. 4 is a configuration diagram of a conventional fuel-engine-driven automotive air conditioner.

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

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

[Description of Signs] 2 Outdoor heat exchanger 4 Refrigerant throttle device 5 Indoor heat exchanger 35 Combustion heater

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60H 1/22 F25B 13/00

Claims (2)

(57) [Claims] In a heat pump air conditioner for a vehicle, which heats at least by a heat pump, a combustion heater for heating a refrigerant is provided, and an outdoor heat exchanger and the combustion heater are provided.
Switching based on at least the outside temperature and solar radiation
A heat pump air conditioner for a vehicle, wherein the air conditioner is used for a vehicle. 2. An outdoor heat exchanger and a fuel cell, taking into account the vehicle interior temperature.
The heat pump air conditioner for a vehicle according to claim 1, wherein the heat pump air conditioner is switched between a sintering heater and a sintering heater .