JPH054511A - Heat pump type air conditioner for automobile - Google Patents

Abstract

PURPOSE:To restrain electric power consumption and to favorably ensure the field of view for driving so as to improve safety by enabling the application of an electric current to an electric heater installed downstream from an interior heat exchanger in an air duct only in a specified operating condition which requires the heating capability really. CONSTITUTION:An interior heat exchanger 6 and an exterior heat exchanger are accommodated in the interior of an air duct 1, and an electric heater 16 is disposed downstream from the interior heat exchanger 6. In such a heat pump type air conditioner for an automobile, an outside air temperature sensor 19, a differential mode detecting means, an outside air introduction mode detecting means and an air blow mode detecting means of a blower 5 are installed in addition to a temperature sensor 17 for detecting the air temperature near the electric heater 16. And an electric current can be applied to the electric heater 16 only when the differential mode, the outside air introduction mode and a preset air blow mode are selected under such a condition that an air temperature near the electric heater 16 is below a preset level in the case of heating opesration and when the external air temperature is below the preset level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner for a vehicle, which is capable of suppressing power consumption and safety of driving a vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, a heat pump type air conditioner for home electric appliances has an auxiliary heater for heating as disclosed in Japanese Patent Laid-Open No. 56-18241, which accompanies frost of an outdoor heat exchanger during heating operation. During the defrost mode operation, the heater is energized to compensate for the insufficient heating capacity during the defrost mode operation.

[0003]

However, in this conventional device, since the heater continues to be energized during defrost mode operation, the heater may overheat, and as a means for preventing this overheating, a predetermined air temperature is set. Turn on heater
The FF control method is conceivable. However, in this method, the heater may be energized even when the heating capacity is not required so much. It cannot be used in air conditioners for electric vehicles, where reduction of power is an important issue.

The present invention solves such a problem and energizes the heater only when the heating capacity is truly required,
An object of the present invention is to provide a heat pump type air conditioner for an automobile, which suppresses power consumption and has a good driving field of view to ensure driving safety of a vehicle.

[0005]

For this reason, the heat pump type air conditioner for an automobile of the present invention comprises an indoor heat exchanger housed in a blower duct and an outdoor heat exchanger, and is located downstream of the indoor heat exchanger. A heat pump type air conditioner in which an electric heater is arranged in a ventilation duct of the air conditioner, the temperature sensor capable of detecting the air temperature near the electric heater, an outside air temperature sensor, a diff mode detecting means, an outside air introducing mode detecting means, and a blower. When the air temperature near the electric heater is equal to or lower than a predetermined temperature during the heating operation, the differential mode, the outside air introduction mode and the predetermined air blowing mode are selected, and the outside air temperature is equal to or lower than the predetermined temperature. Only, the electric heater can be energized, and the heater is energized only when the heating capacity is genuinely needed to suppress the power consumption and improve the driving visibility. A manner is characterized in that so as to attained the safety of operation of the vehicle.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 to 3, reference numeral 1 designates a ventilation duct disposed at an appropriate position of a vehicle, and upstream and downstream of the inside and outside air intake ports 2 and 3. ,
An inside / outside air switching door 4 is provided, and a blower 5 and an indoor heat exchanger 6 are arranged downstream of these doors.

The switching door 4 is made operable via its driving actuator (not shown), and when in the outside air introduction mode, the signal can be inputted to a control device described later via a position sensor (not shown). In addition, the blower 5 can be driven via a blower motor 7, and its ON / OFF signal and a blow mode, in the embodiment, a high Hi signal and a medium Med signal are input to the control device via its operation control circuit. Making it possible

The indoor heat exchanger 6 is inserted in the refrigerating cycle schematically shown in FIG. 2, and a refrigerant conduit 8 piped in the cycle.
Further, the compressor 9, the outdoor heat exchanger 10, the expansion valve 11 or the orifice, and the accumulator 12 are connected. Then, the indoor heat exchanger 6, the compressor 9,
A switching valve 13 that is rotatable via an actuator (not shown) is interposed between the outdoor heat exchanger 10 and the accumulator 12, and the discharge refrigerant path from the compressor 9 to the heat exchangers 6 and 10 can be switched. I have to.

A bypass pipe 14 is connected between the compressor 9 and the outdoor heat exchanger 10, and a solenoid valve 15 is connected to the bypass pipe 14.
Has been inserted. The solenoid valve 15 can be opened for a predetermined time by a deicer (not shown) that controls the defrosting operation when the outdoor heat exchanger 10 is frosted during the heating operation.

An electric heater 16 as an auxiliary heat source is provided on the downstream side of the indoor heat exchanger 6, and a temperature sensor 17 is installed on the downstream side of the heater 16, and its signal can be input to a control device 18. I have to. The control device 18
In addition to this, the air-conditioning operation mode signal of the heating / cooling state and the diff-mode signal can be input through, for example, a diff-mode selection switch (not shown) provided in the instrument panel, and the outside air temperature or the inlet air temperature of the introduced air can be input. The temperature signal can be input via the temperature sensor 19 for detecting the temperature.

A control routine shown in FIG. 4 is stored in the control device 18, and the operation of the electric heater 16 is controlled to be ON / OFF based on the routine. That is,
The control device 18 first determines whether or not the blower 5 is in a stopped state (OFF), and when the blower 5 is in the OFF state, blocks the energization of the electric heater 16, and when the blower 5 is driven,
The air-conditioning operation mode is judged and the heater 16 is blocked from being energized during the cooling operation or the heating operation being stopped. On the other hand, during the heating operation, the heater 16 can be energized under the condition of the air temperature Ti immediately after the electric heater 16. ing.

The controller 18 has the first temperature of the above-mentioned air temperature Ti.
The judgment reference temperature is set, and the upper limit temperature θ1U and the lower limit temperature θ1L are set in the judgment reference temperature.
1U is set to 55 ° C, and the lower limit temperature θ1L is set to 45 ° C.
When the air temperature Ti is higher than the upper limit temperature θ1U, the electric heater 16 is stopped from being energized, and when the lower limit temperature θ1L is lower than the lower temperature θ1, the next step determines whether or not the deicer is activated. If so, the electric heater 16 can be energized under the condition of the air temperature Ti.

That is, the second judgment reference temperature of the air temperature Ti is set in the control device 18, and the upper limit temperature θ2U and the lower limit temperature θ2L are set in this, and in the case of the embodiment,
The upper limit temperature [theta] 2U is set to +10 [deg.] C. immediately before the deicer operation, and the lower limit temperature [theta] 2L is set to -5 [deg.] C. immediately before the deicer operation. When the air temperature Ti is equal to or higher than the upper limit temperature θ2U, the electric heater 16 is prevented from being energized, and when the air temperature Ti is equal to or lower than the lower limit temperature θ2L, it is energized.

On the other hand, the device of the present invention is substantially operable when the deicer is in the OFF state. That is, the outside air introduction mode is detected via the position sensor of the switching door 4, the differential mode is detected via the differential mode selection switch, and a strong Hi blow mode signal is sent via the operation control circuit of the blower motor 7. The electric heater 16 can be energized when it is detected and the outside air temperature To which is lower than a predetermined temperature is detected through the temperature sensor 19.

That is, the control device 18 has an outside air temperature To.
The first judgment reference temperature of is set, and the upper limit temperature θ3U is set for this.
And the lower limit temperature θ3L are set, and in the case of the embodiment, the upper limit temperature θ3U is set to 12 ° C and the lower limit temperature θ3L is set to 10 ° C. When the outside air temperature To is lower than or equal to the lower limit temperature θ3L, the electric heater 16 can be energized.

In addition to the above conditions, the electric heater 16 detects the outside air introduction mode via the position sensor of the switching door 4 and the diff mode via the diff mode selection switch. When the medium Med blow mode signal is detected via the operation control circuit and the predetermined outside air temperature To below the first judgment reference temperature is detected via the temperature sensor 19, the electric heater 16 is energized. It is possible.

That is, the control device 18 has an outside air temperature To.
The second judgment reference temperature of is set, and the upper limit temperature θ4U is set for this.
And the lower limit temperature θ4L are set, and in the case of the embodiment, the upper limit temperature θ4U is set to 2 ° C and the lower limit temperature θ4L is set to 0 ° C. Therefore, in this case, since the blowing temperature is increased by the amount of reduction in the blowing amount of the blower 5, the differential mode operation is effectively performed.

On the other hand, in the case of the inside air introduction mode, not in the differential mode, or when the blower 5 has a blowing mode other than high Hi or medium Med, the outside air temperature To is initially or higher than the upper limit temperature after the electric heater 16 is energized. In the case of or when it occurs, the electric power to the electric heater 16 is blocked.

In the above-described embodiment, the outside air introduction mode of the switching door 4 is detected by the position sensor and the diff mode is detected by the selection switch, but the present invention is not limited to this example and other detecting means may be adopted. it can.

[0020]

In the heat pump type electric vehicle air conditioner configured as described above, when the air conditioner is operated for cooling, the cooling switch is turned on, the blower switch is turned on, the actuator is operated, and the switching valve 13 is turned on. Switch like.

Therefore, the refrigerant in the refrigeration cycle circulates as shown by the arrow in FIG.
The air taken in is cooled in the indoor heat exchanger 6,
The cold air is guided to the blower duct 1 and blown into the passenger compartment.

Next, when heating the air conditioner,
Turn on the heating switch and turn on the blower switch.
N, the actuator is operated, and the switching valve 13 is moved to the position shown in FIG.
Switch like. Therefore, the refrigerant in the refrigeration cycle circulates as shown by the arrow in FIG. 3, and, for example, the air taken into the blower duct 1 from the outside air port 3 is warmed by the indoor heat exchanger 6, and the warm air is blown to the blower duct 1. It is guided and blown out into the passenger compartment.

Simultaneously with the start of such heating operation, the controller 18 receives the air conditioning operation mode signal, in this case the heating operation mode signal, and the blower mode signal of the blower 5 via the operation control circuit of the blower motor 7. The air temperature Ti in the duct immediately after the electric heater 16 is input via the temperature sensor 17, and the outside air temperature T via the temperature sensor 19.
o is entered. Further, the controller 18 is provided with a de-ais
The N / OFF actuation signal and the outside air introduction mode signal are input via the position sensor of the switching door 4, and the diff mode signal is input via the diff mode selection switch. Based on these input signals, FIG. 4 is shown. Start control operation.

That is, the control device 18 first determines whether or not the blower 5 is driven, and if the blower 5 is driven as described above, the control device 18 shifts to the air conditioning operation mode determination process, and in the process, the above-described process is performed. When the heating operation is confirmed, the process proceeds to the next step, and the air temperature T immediately after the electric heater 16 before energization is reached.
Based on i, the necessity of increasing the heating capacity is determined.

When the air temperature Ti is higher than the upper limit temperature θ1U, it is judged that the heating capacity increase is not necessary and the electric current to the electric heater 16 is blocked, and when it is lower than the lower limit temperature θ1L, it is necessary to increase the heating capacity. If it is determined that there is a defect, the process proceeds to the next step, and the operation of the deicer is confirmed in this step.

That is, when the deicer is performing the defrosting operation of the outdoor heat exchanger 10, the solenoid valve 15 is opened, and a part of the high-temperature and high-pressure refrigerant discharged from the compressor 9 is imaginary in FIG. Since it is guided to the bypass pipe 14 as seen from the arrow of the line, the amount of refrigerant supplied to the indoor heat exchanger 6 is insufficient, resulting in insufficient heating capacity.

Therefore, in consideration of the above situation, the controller 18 sets the set temperature of the air temperature Ti to be lower than the first judgment reference value, and in this situation it is necessary to increase the genuine heating capacity. To judge. That is, the air temperature Ti
Is higher than the upper limit temperature θ2U, it is determined that the heating capacity increase is not required, and the energization to the electric heater 16 is blocked, and when the lower limit temperature θ2L or lower, it is determined that the heating capacity needs to be increased genuinely. The electric heater 16 is energized.

On the other hand, when the deicer is in the OFF state, the required amount of refrigerant is supplied to the indoor heat exchanger 6 and the heating capacity needs to be increased even though the refrigeration cycle is operating normally. Therefore, in such a case, the device of the present invention substantially functions.

That is, the outside air introduction mode signal of the switching door 4 and the differential mode signal are input to the control device 18, the blower mode signal of high Hi of the blower 5 is input, and the outside air temperature To is the lower limit. When the temperature is not more than θ3L, the electric heater 16 is energized.

As such a situation, for example, defrost mode operation for removing the fogging of the windshield can be considered. In such a case, the electric heater 16 is heated and its warm air is blown to the inner surface of the windshield. By heating the inner surface, the above cloudiness is removed. After the defrosting of the windshield, when the outside air temperature To changes and becomes equal to or higher than the upper limit temperature θ3U, the power supply to the electric heater 16 is stopped. On the other hand, when the outside air temperature To is still lower than the upper limit temperature θ3U, the electric heater is The energization of 16 is continued, and the above-mentioned glass is prevented from being fogged and the interior of the vehicle is reheated.

As described above, the above-mentioned insufficient heating is caused by, for example, a temporary measure which is usually adopted in order to improve the driving visibility of the vehicle and ensure the driving safety, and it is necessary to increase the genuine heating capacity. Since 16 is energized, its power consumption is kept as small as possible.

In addition, when the outside air introduction mode signal and the differential mode signal are input to the control device 18 and the blow mode signal of the Med in the blower 5 is input, the outside air at that time is input. Even when the temperature To is lower than the lower limit temperature θ4L, the electric heater 16 is energized.

As such a situation, for example, a defrost mode operation for removing the fogging of the windshield more quickly can be considered. In this case, the air volume of the blower 5 is suppressed and the warm air temperature is increased to a higher temperature. It is performed by warming and blowing the warm air to the inner surface of the windshield to quickly heat the inner surface.

The insufficient heating in this case is also caused by the temporary measure which is usually taken to improve the driving visibility of the vehicle and ensure the driving safety, as described above, and the electric heater 16 is consumed. The electric power to be applied can be suppressed as described above.

As described above, according to the present invention, only when the heating capacity of the indoor heat exchanger 6 is insufficient and the capacity needs to be increased genuinely.
Since the electric heater 16 is energized, the power consumption by the heater 16 can be suppressed, the traveling distance, which is an important issue for the electric vehicle, can be improved, the driving visibility can be improved, and the driving safety of the vehicle can be improved. Can be secured.

[0036]

As described above, the heat pump type air conditioner for an automobile according to the present invention is provided with the indoor heat exchanger housed in the air duct and the outdoor heat exchanger, and the air duct on the downstream side of the indoor heat exchanger. A heat pump type air conditioner in which an electric heater is installed in a temperature sensor capable of detecting an air temperature near the electric heater, an outside air temperature sensor, a differential mode detection means, an outside air introduction mode detection means, and a blower blow mode. And a detection means, when the air temperature near the electric heater during heating operation is below a predetermined temperature, a diff mode, an outside air introduction mode and a predetermined blowing mode are selected, and the outside air temperature is below a predetermined temperature Since it is possible to energize the heater, energize the heater only when the heating capacity is genuinely required, for example, when preventing windshield fog. It is possible to suppress the power consumption, together with the improvement of the travel distance of the vehicle is suitable for electric vehicles is an important issue, it is possible to improving the driving view field to ensure the safety of operation of the vehicle.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is a schematic diagram of a refrigeration cycle during a cooling operation of the present invention.

FIG. 3 is a schematic diagram of a refrigeration cycle during heating operation of the present invention.

FIG. 4 is a flowchart showing a control system of the present invention.

[Explanation of symbols]

 1 Blower Duct 5 Blower 6 Indoor Heat Exchanger 10 Outdoor Heat Exchanger 16 Electric Heater 17, 19 Temperature Sensor

Claims (1)

Claims: 1. An indoor heat exchanger housed in a ventilation duct,
A heat pump type air conditioner comprising an outdoor heat exchanger, wherein an electric heater is arranged in a blower duct downstream of the indoor heat exchanger, wherein a temperature sensor capable of detecting an air temperature near the electric heater and an outside air temperature. A sensor, a differential mode detection means, an outside air introduction mode detection means, and a blower blow mode detection means are provided, and the air temperature near the electric heater during heating operation is below a predetermined temperature, and the differential mode, the outside air introduction mode and a predetermined blow A heat pump type air conditioner for an automobile, characterized in that the electric heater can be energized only when the mode is selected and the outside air temperature is below a predetermined temperature.