JPS5946807B2 - Anti-fog control method for vehicle air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-fog control method for a vehicle air conditioner, which prevents fogging on the inner surface of a glass by a simple operation.

While driving a car, when the temperature inside the vehicle is high or when there is a large temperature difference between the outside and the inside of the vehicle, fogging may occur on the inner surface of the glass, which may interfere with driving.

Therefore, the driver manually turns on the compressor,
The amount of outside air introduced is adjusted by adjusting the blower setting lever, and the defrost mode is set by adjusting the mode setting lever, but if the driver is forced to perform such operations, it becomes a major hindrance to driving. It's dangerous.

Therefore, this invention provides a dew condensation removal switch and
Equipped with an outside air temperature sensor, these input signals automatically select and control the compressor operation, selection of intake amount of outside air and inside air, increase of blown air, etc., and easy operation eliminates the above drawbacks. This will be explained in detail below using examples.

FIG. 1 is a diagram showing an embodiment of the anti-fogging control method for a vehicle air conditioner according to the present invention. In the figure, an evaporator 1 is installed on the upstream side and a heater core 2 is installed on the downstream side. The evaporator 1, compressor 3, condenser 6, liquid receiver 7, and expansion valve 8 constitute a cooling cycle, which is driven by an electromagnetic clutch 4 of the compressor 3. One drive control is performed by the output from the control circuit 5.

The heater core 2 has the function of warming the incoming air.
The output from the control circuit 5 opens and closes the water cock 9 to control the heating temperature, and the control actuator 11 of the air mix door 10 controls the supply of air.

That is, the air mix door 10 is provided upstream of the heater core 2, and the temperature is appropriately controlled by changing the mixing ratio of cold air and hot air depending on the opening degree of the air mix door 10.

The blower 12 selectively sucks outside air or inside air from an outside air port 13 or an inside air port 14 depending on the position of the inside/outside air switching door 15, and sends it to the evaporator 1.

The rotation speed of the blower 12 is sequentially controlled from stop to maximum rotation by the output from the control circuit 5.

The inside/outside air switching door 15 is controlled by the output of the control circuit 5 via the actuator 16.

The most downstream part of this device is branched into an upper outlet 17 and an outlet 18, and the outlet 18 is further branched into a defrost outlet 181 and a lower outlet 182.
A mode switching door 19 is provided at the branching point between 7 and 18, and a mode switching door 20 is provided at the air outlet 18, and the door 19 is controlled by the output of the control circuit 5 via an actuator 22. Further, the door 20 is similarly controlled by the output of the control circuit 5 via the actuator 22.

That is, in the cooler mode, the door 19 closes the air outlet 18 and opens the air outlet 17, and in the heater mode, the door 19 closes the air outlet 18 and opens the air outlet 17.
closes the air outlet 17.

In the pie level mode, the door 19 is in the open position,
Door 20 is opened, and in the defrost mode, door 1 is opened.
9 closes the air outlet 17 and the door 20 closes the defrost air outlet 18
．． Its position is displaced so that the wind is sent to.

The above vehicle air conditioner is controlled by the output from the control circuit 5, and the control circuit 5 includes a condensation removal switch 24, an outside temperature sensor 25, and a mode setting device 26.2.
7.28 and is controlled by determining the signal from 7.28.

The mode setter 26 sends out a cooler mode setting signal, the mode setter 27 sends out a pie level mode setting signal, and the mode setter 28 sends out a heater mode setting signal.

Next, the operation of the device shown in FIG. 1 will be explained using the flowchart shown in FIG. 2. First, when fogging occurs on the window glass of the vehicle, the driver turns on the dew condensation removal switch 24.

Based on this signal and the signal from the outside air temperature sensor 25, the control circuit 5 determines whether the outside air temperature ta is, for example, 5° C. (operating allowable temperature 1.) or higher, a temperature preferable for driving the compressor 3. If the temperature is 5° C. or higher, the electromagnetic clutch 4 is controlled and the compressor 3 is driven.

As a result, the air introduced by the blower 12 is dehumidified by the evaporator 1, so air with low absolute humidity is sent into the vehicle interior, the absolute humidity in the vehicle interior is reduced, and the effect of defogging the window glass is obtained.

On the other hand, if the outside air temperature ta is lower than the operating allowable temperature t1, the control circuit 5 controls the actuator 16 to drive the inside/outside air switching door 15 to set the outside air introduction rate to 100% and introduce a large amount of outside air with low absolute humidity. , lowers the absolute humidity inside the vehicle and removes fogging from the window glass.

If 100% outside air has already been introduced, the control circuit 5 controls the blower 12 to increase the amount of outside air introduced, thereby increasing the amount of ventilation in the passenger compartment.1. It reduces the absolute humidity inside the vehicle and increases the air volume from the defroster to remove fog from the window glass.

That is, the control circuit 5 determines whether the outside air temperature ta is higher than the operating allowable temperature t based on the output from the dew condensation removal switch 24 and the signal from the outside air temperature detection sensor, and when it is higher than the operating allowable temperature tl. Turn on compressor 3.

When the operating allowable temperature is lower than 1°, the outside air introduction rate or the outside air introduction rate and the outside air introduction amount are increased.

Also, depending on the mode, the amount of air from the defroster outlet is increased.

This also removes semi-fogging, allowing you to continue driving safely.

Therefore, the driver only has to operate the dew condensation removal switch 24, so there is no problem in driving.

In addition, in the present invention, when the compressor 3 is turned on, the actuator 16 is controlled and the outside air introduction rate is set to, for example, 30%, as shown in FIG. The dehumidification effect may be increased by

Also, compressor 3, actuator 16, blower 12
The blowout mode may be set in conjunction with the control.

For example, if the heater mode is already set, the outside air port 1
3 and introduce outside air from the outside air port 13. If outside air is already introduced, increase the rotation speed of the blower 12 to increase the airflow, and if the air is already increased, open the door 20! Control is performed to increase the air volume of the defrost outlet 18f.

In this case, the rear heat source may be energized.

As explained above, according to the present invention, in a vehicle air conditioner equipped with a control circuit for controlling at least a compressor, an inside/outside air switching door, and a blower, a condensation removal switch and an outside temperature sense are provided, and the control circuit is provided with a condensation removal switch and an outside temperature sense. When the condensation removal switch is activated, the compressor is controlled to perform dehumidification when the outside air temperature is above the operating allowable temperature of the compressor, and when the outside air temperature is below the operating allowable temperature, the outside air switching door is controlled to increase the outside air introduction rate. In addition to this procedure for increasing the outside air introduction rate, the blower is controlled to increase the amount of outside air introduced, so the driver only has to operate the condensation removal switch to remove condensation, which improves driving safety. can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the anti-fogging control method for a vehicle air conditioner according to the present invention, and FIG. 2 is a flowchart showing its operation. 1... Evaporator, 2... Heater core, 3... Compressor, 4... Electromagnetic clutch, 5... Control circuit, 1'0・・・・・・
・Air mix door, 12...Blower, 15・
...Inside/outside air switching door, 24...Condensation removal switch, 25...Outside air temperature sensor.

Claims (1)

[Claims] 1. A condensation removal switch, and a control circuit that controls a compressor, an inside/outside air switching door, and a blower based on a signal from the condensation removal switch and a signal from an outside temperature sensor, and the control circuit enables the condensation removal switch to be turned on. Sometimes it is determined whether the outside temperature is higher than the set temperature 11,
When the set temperature is higher than t1, the compressor is driven, and when the set temperature is t1, the inside/outside air switching door is switched to the outside air introduction side, or the inside/outside air switching door is switched to the outside air introduction side and the air volume of the blower is increased. An anti-fog control method for an air cooling device for a vehicle, characterized in that: