JPH06305321A - Heat pump type air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To use a ventilating duct in common for various mechanical and motor air conditioners by supplying cooling water cooled by air outside a compartment in warming running to a heater core to cool blast air while supplying warm water in cooling running to heat the blast air. CONSTITUTION:A heat pump type air conditioner for a vehicle for driving a compressor 1 with a motor 8, for example, an air conditioner for an electric automobile, cannot use cooling water for an engine in warming running. Thus, a four-way change-over valve 7 is changed over and air from a blast device 6 is heated by an indoor heat exchanger 5 to condense and liquefy a refrigerant. Thereafter, the refrigerant is introduced through a throttle device 4 into an outdoor heat exchanger 2 to cool air outside a compartment while practicing the warming of the heat pump for absorbing heat of the refrigerant and vaporizing the refrigerant. The motor 8 is controlled by an operating unit 30 to adjust blow-off temperature. Then, an outdoor air-water heat exchanger 21 is provided outside the compartment and a heater core 15 is disposed in a blast duct 20, while a water pump 22 is disposed in a piping for interconnecting these heater core 15 and exchanger 21 to each other.

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 cooling and heating a vehicle with a heat pump and a heater core.

[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. 5, the cooling action is to drive a compressor 1 for compressing a refrigerant by an engine 27 to generate outdoor heat. After the heat is radiated to the air outside the vehicle compartment by the exchanger 2 and the air blower 3 for the outdoor heat exchanger to condense and liquefy the refrigerant, the refrigerant is guided to the indoor heat exchanger 5 via the refrigerant expansion device 4, and the indoor air blower is supplied. The air blown by 6 was evaporated while cooling and the air-cooling action was performed.

The heating function 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. Therefore, when the compressor 1 is operated, the temperature of the blown air can be continuously adjusted from warm air to cold air, and heating and cooling can be continuously changed.

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 the fuel-driven automobile, the blowout temperature is controlled by controlling the electric motor drive device 9 that drives the electric motor 8 by the operation unit 30 to adjust the rotation speed of the compressor 1. Do it. Further, switching between heating and cooling is performed by switching the refrigerant flow path using the four-way switching valve 7 by the heating / cooling operation switching device 31.

[0006]

As described above, in the electrically driven vehicle, the blowout temperature must be adjusted by adjusting the rotation speed of the electric motor (compressor). However, the rotation speed of the electric motor (compressor) that adjusts the heating and cooling capacity cannot be lowered arbitrarily to protect the compressor such as ensuring lubricating oil circulation, and the rotation speed has a lower limit of the minimum rotation speed. It is set. Therefore, depending on the environmental conditions such as the middle season when the heat load is small, the blowing temperature may be too high and the heating capacity may be excessive during the heating operation even at the lowest rotation speed.

As an example of excess heating capacity, FIG. 8 shows a heating operation diagram of a conventional vehicle heat pump type air conditioner. Figure 6
The operation unit 30 in the configuration diagram of the conventional vehicle heat pump type air conditioner controls the electric motor drive device 9 that drives the electric motor 8 to adjust the rotation speed of the compressor 1 to adjust the blowout temperature. There is. When the air conditioning is started, the temperature inside the vehicle is lower than the target temperature, so the number of revolutions is increased to increase the blowout temperature. When the vehicle interior temperature approaches the target temperature, the rotation speed is reduced. Then, the target temperature is reached. However,
The vehicle interior temperature does not reach the target temperature and is maintained at that target temperature, but even at the lower limit minimum rotation speed (minimum rotation speed),
The target temperature exceeds the specified value. Therefore, as a countermeasure, the compressor is stopped but the heating capacity becomes zero, so that the vehicle interior temperature becomes lower than the target temperature. Therefore, the vehicle interior temperature is maintained at the target temperature by repeatedly stopping and operating. As a result, the blowing temperature repeatedly rises and falls, which impairs comfort, and is disadvantageous in terms of durability and reliability due to repeated stop and operation of the compressor. Therefore, it is necessary to lower the heating capacity at the lowest rotation speed to lower the blowout temperature, and there are methods such as bypassing the compressor, but the air conditioner becomes large and complicated.

Similarly, FIG. 9 shows a cooling operation diagram of a conventional vehicular heat pump type air conditioner as an example of excessive cooling capacity during cooling operation. When the air conditioning is started, the vehicle interior temperature is higher than the target temperature, so the number of revolutions is increased and the blowout temperature is lowered. When the vehicle interior temperature approaches the target temperature, the rotation speed is reduced. Then, the target temperature is reached. However, the vehicle interior temperature does not reach the target temperature and is maintained at the target temperature, and the target temperature exceeds the target value even at the lower limit minimum rotation speed (minimum rotation speed). Therefore, as a correspondence,
Although the compressor is stopped, the cooling capacity becomes zero, so the vehicle interior temperature becomes higher than the target temperature. Therefore, the vehicle interior temperature is maintained at the target temperature by repeatedly stopping and operating. As a result, the blowing temperature repeatedly rises and falls, which impairs comfort, and is also disadvantageous in terms of durability and reliability due to repeated stop and operation of the compressor. Therefore, by providing an electric heater 28 and an electric heater capacity adjusting device 29 as shown in the configuration diagram of the conventional electric heater heating / heat pump cooling vehicle air conditioner in FIG. 7, and slightly raising the blowout temperature by the electric heater 28, It is possible to solve the problem caused by repeatedly stopping and operating the compressor.

However, although a considerable amount of electric power is required as the power source of the electric heater 28, in the case of an electrically driven vehicle, if the power consumption of the air conditioner becomes large, the power consumption of the vehicle drive electric motor will be suppressed and the running performance will be reduced. Will affect. Further, although high voltage / low current or low voltage / high current must be used, since the ventilation duct 20 is installed in the passenger compartment, it is particularly necessary to take safety measures against the power source.

If an indoor heat exchanger for heating is provided instead of the electric heater 28, it must be installed in the ventilation duct 20. Ventilation duct 20 for indoor heat exchanger for heating
If it is installed in, the ventilation duct 20 of the conventional air conditioner for a vehicle driven by a fuel engine cannot be shared. Therefore, a new ventilation duct 20 must be manufactured for an electrically driven vehicle. However, since the number of electrically driven vehicles is small at the beginning, the cost becomes considerably high. Further, a refrigeration cycle component for the indoor heat exchanger for heating is required, which makes the air conditioner large and complicated.

Further, even if the rotation speed of the electric motor (compressor) is changed to adjust the blowout temperature (vehicle interior temperature), it takes time for the refrigeration cycle to stabilize, so that the blowout temperature (vehicle interior temperature) can be tracked. It slows down comfort. For example,
The occupants must endure the heat from the sunlight for a while because the cold wind cannot be immediately emitted even if the sunlight becomes strong.

Therefore, according to the present invention, the ventilation duct of the conventional air conditioner for a vehicle driven by a fuel engine can be commonly used, and the structure is simple,
Heat pump type for vehicles that consumes less power, is safe, and prevents blowout temperature fluctuations in environmental conditions with a small heat load to obtain a comfortable blowout temperature, improve durability reliability, and quickly change the blowout temperature. The purpose is to provide an air conditioner.

[0013]

In order to solve the above-mentioned problems as a first means, the present invention performs heat pump heating or cooling operation by heating or cooling the air blown into the vehicle interior with an indoor heat exchanger. During the heating operation, cold water cooled by the air outside the passenger compartment is caused to flow through the heater core, and the blast air is cooled by the heater core. During the cooling operation, hot water heated by the outside air of the passenger compartment is caused to flow through the heater core. The blast air is heated at.

In order to solve the above-mentioned problems, the present invention provides, in the first means, the temperature of the air blown into the passenger compartment, the air blown by bypassing the heater core, and the heater core for cooling or heating. Adjust by changing the ratio of blown air.

[0015]

According to the first means of the present invention, the heat pump heating or cooling operation is performed by heating or cooling the air blown into the vehicle interior by the indoor heat exchanger, and is cooled by the air outside the vehicle interior during the heating operation. The chilled water is caused to flow through the heater core, the blast air is cooled by the heater core, the hot water heated by the air outside the vehicle compartment is caused to flow through the heater core during the cooling operation, and the blast air is heated by the heater core. Therefore, during heating operation, the blast air heated excessively in the indoor heat exchanger due to excess capacity is cooled by the heater core in which cold water cooled by the outside air of the vehicle is flowed to lower the blast air temperature. You can

Further, during the cooling operation, the blast air cooled excessively by the indoor heat exchanger due to excess capacity is heated by the heater core in which warm water heated by the outside air of the vehicle is flown,
The blast air temperature can be raised. Therefore, when operating in environmental conditions with a small heat load such as the middle season, by adjusting the blowout temperature slightly with the heater core, a comfortable blowout temperature can be obtained without repeating the stop and operation of the compressor, durability and reliability The property is improved.

Further, since the electric heater is not used, there is no power consumption for the electric heater, and it is not necessary to pay particular attention to safety regarding high voltage / low current or low voltage / large current as the power source of the electric heater.

Further, since hot water warmed by the air outside the passenger compartment is caused to flow through the heater core and the blast air is heated by the heater core, the ventilation duct and the heater core of the conventional air conditioner for a fuel engine driven automobile can be shared, so that a new ventilation is provided. No duct development is required and no special parts are required as a means for reducing the capacity, so the structure is simple and the cost is reduced.

According to the second means of the present invention, in the first means, the temperature of the blast air into the vehicle compartment is a ratio of the blast air bypassing the heater core and the blast air cooled or heated by the heater core. Change and adjust. Therefore,
In the first means, the temperature of the blown air into the passenger compartment is adjusted by changing the ratio of the blown air bypassing the heater core and the blown air cooled or heated by the heater core. Therefore, in addition to the action of the first means, the temperature of the blown air can be rapidly changed by adjusting the opening degree of the mix damper.

[0020]

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 vehicle heat pump type air conditioner is that the embodiment of the present invention uses the outdoor air / water heat exchanger 21 outside the vehicle as compared with the conventional example of FIG. The outdoor air and the water are configured to exchange heat with each other, and the heater core 15 in the conventional air conditioner for a vehicle driven by a fuel engine is installed in the ventilation duct 20. A water pump 22 for flowing water is installed in a pipe connecting the outdoor air / water heat exchanger 21 and the heater core 15.

In the case of heating, the four-way switching valve 7 is set by the heating / cooling operation switching device 31 as shown by the solid line in FIG. The discharged refrigerant is guided to the indoor heat exchanger 5 by the compressor 1. Next, the air blown by the indoor air blower 6 is heated to condense and liquefy the refrigerant, which is then conveyed to the outdoor heat exchanger 2 via the refrigerant expansion device 4 and blown by the outdoor heat exchanger air blower 3. Cool the air and evaporate.

FIG. 3 shows an air conditioning operation diagram according to the first embodiment of the present invention. In an environmental condition with a small heat load such as the middle season, when the air conditioning is started, the vehicle interior temperature is farther than the target temperature, so the heating capacity is increased. Therefore, both the blowout temperature and the compressor rotation speed are high. When the vehicle interior temperature approaches the target temperature, the heating capacity is lowered, so both the blowout temperature and the compressor rotation speed are lowered. However, because of the environmental condition with a small heat load, the vehicle interior temperature reaches the target temperature, but exceeds the target temperature, and becomes higher than the target temperature. So at point A,
The water pump 22 is activated. As a result, the blow-out temperature becomes lower, so that the vehicle interior temperature that was higher than the target temperature returns to the target temperature, and further becomes lower than the target temperature. Therefore, this time, at point B, the heating capacity is increased by the heating / cooling operation capacity adjustment device 30 and the compressor rotation speed is increased to raise the blowout temperature, so that the vehicle interior temperature reaches and is maintained at the target temperature.

For example, the outside temperature of the vehicle is 15 ° C., the outlet temperature at the point A is 37 ° C., and the inside temperature of the vehicle is 32 ° C. Water pump 2
2 is operated, water of 15 ° C, which is the same as the outside temperature of 15 ° C, is sent to the heater core 15, and the outlet temperature becomes 26 ° C.
The vehicle interior temperature becomes 21 ° C. Therefore, at the point B, the heating capacity is increased by the heating / cooling operation capacity adjusting device 30 and the compressor rotation speed is increased to raise the outlet temperature to 30 ° C., and the vehicle interior temperature is kept at the target temperature 25 ° C. Will be made.

The same operation is performed in the case of cooling. 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 first embodiment of FIG. 1 is that a mix damper 16 and a mix damper opening adjustment device 23 are added to the second embodiment.

In the case of cooling, the four-way switching valve 7 is set by the heating / cooling operation switching device 31 as shown by the broken line in FIG. Therefore,
The refrigerant discharged from the compressor 1 is guided to the outdoor heat exchanger 2 and is condensed by the air blown from the outdoor heat exchanger air blower 3. Next, the refrigerant is carried to the indoor heat exchanger 5 via the refrigerant expansion device 4, and cools and evaporates the air blown by the indoor air blower 6.

FIG. 4 shows an air conditioning operation diagram according to the second embodiment of the present invention. In an environmental condition with a small heat load such as the middle season, when the air conditioning is started, the vehicle interior temperature is higher than the target temperature, so the rotation speed is increased and the blowout temperature is decreased. When the vehicle interior temperature approaches the target temperature, the rotation speed is reduced. Then, the target temperature is reached. However, the vehicle interior temperature does not reach the target temperature and is maintained at the target temperature,
Even at the lower limit of the minimum rotation speed (minimum rotation speed), the target temperature is exceeded by a predetermined value and it becomes cold.

Therefore, at the point A, the water pump 22 is operated and the hot water produced by the outdoor air / water heat exchanger 21 is
The water pump 22 allows the heater core 15 to flow. Then, the mix damper opening adjustment device 23 gradually opens the mix damper 16 to gradually warm the blown air, and the temperature inside the vehicle reaches the target temperature at point D.

For example, the outside temperature of the vehicle is 30 ° C., the outlet temperature at the point C is 12 ° C., and the inside temperature of the vehicle is 21 ° C. Water pump 2
2 is operated to send water having the same outside temperature of 30 ° C. as the outside temperature of 30 ° C. to the heater core 15, and the mix damper 16 is gradually opened to change the outlet temperature from 12 ° C. to 16 ° C. It will reach and maintain 25 ° C.

The same applies to the case of heating. Where E
When the solar radiation suddenly increases at the point, the blow-out temperature can be immediately lowered by immediately closing the mix damper 16, and a comfortable feeling can be maintained without feeling the heat. When the solar radiation suddenly decreases at point F, the blow-out temperature can be immediately raised by immediately opening the mix damper 16, and a comfortable feeling can be maintained without feeling cold.

In the above, the example in which the heating / cooling switching and the adjustment of the blown air temperature are performed manually has been shown, but the effect is the same when a control device for automatically setting according to various environmental conditions is provided. That is clear.

Various arrangements, numbers, configurations, etc. of heat exchangers can be applied within the scope of the present invention.

[0033]

According to the present invention, the heat pump heating or cooling operation is performed by heating or cooling the air blown into the vehicle interior with the indoor heat exchanger, and the cold water cooled by the air outside the vehicle interior during the heating operation. To the heater core, the blower air is cooled by the heater core, hot water heated by the air outside the vehicle compartment is passed through the heater core during the cooling operation, and the blower air is heated by the heater core. Therefore, during heating operation, the blast air heated excessively in the indoor heat exchanger due to excess capacity is cooled by the heater core in which cold water cooled by the outside air of the vehicle is flowed to lower the blast air temperature. You can

Further, during the cooling operation, the blast air that has been cooled more than necessary by the indoor heat exchanger due to the excess capacity is heated by the heater core in which warm water heated by the outside air of the vehicle is flown,
The blast air temperature can be raised.

Therefore, when operating in an environmental condition where the heat load is small, such as in the middle season, by adjusting the blow-out temperature slightly with the heater core, it is possible to repeat the stop and operation of the compressor.
A comfortable blowing temperature is obtained, and durability and reliability are improved.

Further, since the electric heater is not used, there is no power consumption for the electric heater, and it is not necessary to pay particular attention to safety regarding high voltage / low current or low voltage / large current as the power source of the electric heater.

Further, since hot water warmed by the air outside the passenger compartment is caused to flow through the heater core and the blast air is heated by the heater core, it is possible to share the ventilation duct and the heater core of the conventional air conditioner for a fuel engine driven automobile, so that a new ventilation is possible. No duct development is required and no special parts are required as a means for reducing the capacity, so the structure is simple and the cost is reduced.

In claim 2, in claim 1,
The temperature of the blown air into the vehicle compartment is adjusted by changing the ratio of the blown air that bypasses the heater core and the blown air that is cooled or heated by the heater core. Therefore, the temperature of the blown air into the vehicle compartment is adjusted by changing the ratio of the blown air that bypasses the heater core and the blown air that is cooled or heated by the heater core. Therefore, in addition to the effect of the first aspect, the temperature of the blown air can be quickly changed by adjusting the opening degree of the mix damper.

[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 heating operation waveform diagram of the vehicle heat pump type air conditioner according to the first embodiment of the present invention.

FIG. 4 is a cooling operation waveform diagram of the vehicle heat pump type air conditioner according to the second embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional air conditioner for a vehicle driven by a fuel engine.

FIG. 6 is a configuration diagram of a conventional vehicle heat pump type air conditioner.

FIG. 7 is a configuration diagram of a conventional vehicle air conditioner for heating an electric heater and cooling a heat pump.

FIG. 8 is a heating operation waveform diagram of a conventional vehicle heat pump type air conditioner.

FIG. 9 is a cooling operation waveform diagram of a conventional vehicle heat pump type air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Outdoor heat exchanger 3 Blower for outdoor heat exchanger 4 Refrigerant expansion device 5 Indoor heat exchanger 6 Indoor blower 7 Four-way switching valve 8 Electric motor 9 Electric motor drive 10 Vent outlet 11 Heat outlet 12 Defrost blow Outlet 13 Vent / heat air outlet switching damper 14 Defrost air outlet damper 15 Heater core 16 Mix damper 17 Vehicle exterior air inlet 18 Vehicle interior air inlet 19 Inlet air switching damper 20 Ventilation duct 21 Outdoor air / water heat exchanger 22 Water pump 23 Mix damper opening adjustment device 24 Missing 25 Missing 26 Missing 27 Engine 28 Electric heater 29 Electric heater capacity adjusting device 30 Heating / cooling operation capacity adjusting device 31 Heating / cooling operation switching device

Claims (2)

[Claims] 1. A heat pump type air conditioner for a vehicle, which heats or cools air blown into a passenger compartment by an indoor heat exchanger to perform heat pump heating or cooling operation, is cooled by air outside the passenger compartment during heating operation. Cold water is flown to the heater core, the blower air is cooled by the heater core, hot water heated by outside air in the vehicle is flown to the heater core during cooling operation, and the blower air is heated by the heater core. Heat pump type air conditioner. 2. The temperature of the blown air into the vehicle compartment is adjusted by changing the ratio of the blown air bypassing the heater core to the blown air cooled or heated by the heater core. Vehicle heat pump air conditioner.