JPS6355450B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a demist control method in a vehicle air conditioner, and more particularly to a control method for controlling the demist operation of a vehicle air conditioner according to outside temperature and time factors. .

Generally, when a vehicle is operated, fogging may occur on the inner surface of a window glass due to moisture emitted by a passenger, moisture in air introduced from the outside, or a temperature difference between the air inside the vehicle and the outside air.

In such cases, the driver normally operates the various operating parts of the vehicle air conditioner to adjust the fan rotation speed, compressor operating mode, air mix door, which adjusts the mixing ratio of cold air and warm air, and the air conditioning system. Each control device, such as a switching door and a mode switching door that switches the air blowing mode, is individually controlled to cause the air conditioner to perform a demisting operation to defog the window glass. However, if the occupants were to operate each control device individually in this way, they would not only lose their attention while driving, impairing driving safety, but also require the above-mentioned demisting operation to continue for a long time. This has the disadvantage that the air conditioning condition in the vehicle interior changes and is hindered, making it impossible to perform good air conditioning. That is, if the compressor is driven when the temperature of the outside air is low, such as in winter, not only does this place a burden on the compressor, but the temperature inside the vehicle also decreases, resulting in a poor feeling for the occupants. In addition, even in the summer, if the fan speed is set to high speed and the compressor is driven, if this condition continues for a long time, the temperature inside the vehicle will drop extremely, which may affect the feeling of the occupants as described above. This will cause it to decline.

Therefore, an object of the present invention is to automatically control the rotational speed of the blower, the operating mode of the compressor, the opening degree of the air mix door, the opening degree of the blowout mode switching door, and the opening degree of the inside/outside air switching door when the demisting switch is turned on. Based on the operation of the demist switch, each control device constituting the vehicle air conditioner is controlled to perform the demisting operation, and the demisting operation is performed based on the outside temperature and time factors. Accordingly, the above-mentioned demisting operation is adjusted to maintain the air conditioning in a good condition, thereby eliminating the above-mentioned drawbacks, and will be described in detail below using examples.

1 and 2 are a simplified configuration diagram and a block diagram showing an embodiment of a demist control method in a vehicle air conditioner according to the present invention, and in each figure, a vehicle air conditioner 1 supplies inside air or outside air to the Duct 2 that guides indoors and inside/outside air switching door 3
, a blower 4 for introducing inside and outside air, an evaporator 5 for cooling the introduced air, a heater core 6 for heating the introduced air, an air mix door 7 for adjusting the mixing ratio of cold air and warm air, and a mode for setting the blowing mode. It is composed of switching doors 8 and 9. The doors 3, 7, 8, 9 are controlled by motor actuators 10, 11, 12, 13, for example.
Further, the evaporator is cooled by the operation of a compressor, and this compressor is operated by an electromagnetic clutch 1.
It is driven by the operation of 4. The mode switching doors 8 and 9 control the amount of air blown out from each of the air outlets 15 toward the face, the defrost outlet 16, and the outlet 17 toward the feet, and set the air outlet mode to ventilate mode, Set to heater mode and defrost mode. Note that the air blown out from the defrost outlet 16 is blown toward the window side of the vehicle. The blower 4, actuator 10, etc. are controlled by a control device 18 as shown in FIG.
The temperature of the blown air is controlled by controlling the opening degree of the air mix door 7 based on the set temperature signal T _D from the air mixer door 7 . In addition, the actuators 12 and 13 are controlled according to the operating amount of the blowout mode setting section 22 to set the air blowing mode to ventilate mode, heater mode, defrost mode, etc., and the inside/outside air switching setting section 23 is operated. The actuator 10 is controlled according to the amount of air, the inside/outside air switching door 3 is set to the inside air introduction mode or the outside air introduction mode, and when the cooler control switch 24 is turned on, the electromagnetic clutch 1 is turned on.
The evaporator 5 is cooled by exciting the air blower 4 and driving the compressor, and furthermore, the rotation speed of the blower 4 is controlled to high speed, medium speed, or low speed according to the setting amount of the blower rotation speed setting section 25. In this case, in the medium speed range, the speed can be further finely adjusted to high speed and low speed, so the rotation speed of the blower 4 can be controlled in four stages. The control device 18 is controlled by a demist switch 26 installed at a location that is most easily operated by the passenger, and when this switch 26 is turned on, the blower 4, compressor, and air mixer door 7 are turned on.
By automatically controlling the opening degree of the mode switching doors 8 and 9, and the opening degree of the inside/outside air switching door 3, the vehicle air conditioner 1 is configured to perform a demisting operation. It can clear the fog on the inside of the window glass.

Note that the above demisting operation is performed using the outside air temperature signal _{t a} from the outside air temperature sensor 21 that is input to the control device 18 ,
It is controlled by the timing signal T _l from the timer 27 according to the flowchart shown in FIG. That is, when the demist switch 26 is turned on while the ignition switch 28 is on, the vehicle air conditioner performs a demist operation by the control device 18. At this time, if the outside air temperature is lower than the set temperature t ₁ (for example, 2°C), the control device 18 stops the compressor based on the signal _ta from the outside air temperature sensor 21 corresponding to this temperature t ₁ . , and if the temperature is higher than the set temperature _{t 2 (} for example, 6° C.), which is slightly higher than the outside air temperature t 1 , the control device 18 puts the compressor into the operating state based on the signal t _a corresponding to this temperature t ₂ and puts the compressor into demist operation. Let them do it. In other words, when the outside air temperature is lower than the above temperature _t1 , the blower 4
The rotational speed is set to high speed, the electromagnetic clutch 14 is deenergized, the compressor is stopped, the mode switching doors 8 and 9 are set to the defrost mode, and the inside/outside air switching door 3 is set to the outside air introduction mode. . In addition, at this time, air mix door 7
is controlled based on a signal from a manually operated temperature setting device 19. Normally, when the outside air temperature is lower than the temperature _t1 , the air mix door 7 is in a state to increase the mixing ratio of warm air. Therefore, by this demisting operation A, the humidity is relatively low on the inner surface of the window glass, and low humidity outside air heated to some extent by the heater core 6 is blown at high speed, so that the fog attached to the window glass can be cleared. . On the other hand, when the demist switch 26 is turned on, the timer 27 _starts timing operation and outputs a timing signal T _l to the control device 18 after the set time, for example, 1 minute has elapsed. The rotational speed of No. 4 is lowered to a medium speed to reduce the demisting ability of the demisting operation A. Further, at this time, the mode switching doors 8 and 9 blow out air from both the foot outlet 16 and the defrost outlet. However, in this case, when the outside air temperature is higher than the set temperature (for example -5℃), the rotation speed of the fan 4 is set to a low speed in the medium speed range, and the outside air temperature is set at the set temperature.
When the temperature is below t ₀₁ (for example, −9° C.), the rotational speed of the blower is set to a high speed in the medium speed range to increase the demisting capacity. That is, when the outside air temperature is extremely low, such as below the set temperature t ₀₁ , cloudy weather does not easily clear up, so the demisting ability is improved at this time. The time set by the timer in this way (the time required to sufficiently remove fog by demisting operation A)
Since the demisting capacity is reduced after performing the demisting operation A, the air conditioning condition is not disturbed, and since the demisting capacity is reduced after most of the fogging has been removed, the fogging can be completely removed. The demisting operations B and C in which the demisting capacity is reduced continue, and when the fog is completely removed, the demisting switch 26 is turned off by the passenger, and the demisting operations B and C are completed. In this case, demisting operation A,
B and the output from the AND element 29 that detects the on state of the demist switch 26, if the demist switch 26 continues to be on, the vehicle air conditioner 1 operates as a demist with a reduced demisting capacity. Perform actions B and C. That is,
When the demist switch is turned on for the first time, demist operation A is performed, and thereafter demist operation A is performed.
Demisting operation B with reduced demisting ability than
Do C.

Next, if the outside air temperature is equal to or higher than the set temperature _t2 , the control device 18 increases the rotational speed of the blower 4, excites the electromagnetic clutch 14, and turns on the compressor. In this case, the air mix door 7 is controlled based on a signal from a manually operated temperature setting device 19, and the direction of the mode air outlet is set to a direction desired by the occupant. Further, it is determined whether the outside air temperature is higher or lower than a separately provided set temperature which is higher than the set temperature _t2 , and if it is high, the inside air introduction mode is set, and if it is low, the outside air introduction mode is set. As a result, demisting operation X is performed. By rotating the blower at high speed and operating the compressor,
Since the absolute humidity of the inside air can be lowered by the evaporator 5, fogging on the inner surface of the window glass can be removed. In this case, the mode switching doors 8 and 9 are controlled according to the setting amount of the blowout mode setting section 22, and are set to one of the ventilate mode, heater mode, defrost mode, etc. The reason why the opening degree of the air mixer door 7 is controlled to increase the mixing ratio of warm air is to compensate for the decrease in the internal air temperature due to the operation of the compressor. Next, when a certain period of time has _elapsed after the above-mentioned demisting operation
The rotation speed is controlled to be a low speed in the medium speed range, and the mode of the inside/outside air switching door 3 is set to the outside air introduction mode. This causes the vehicle air conditioner to perform a demisting operation Y in which the demisting capacity is lower than in the case of the demisting operation X. Therefore, after the fog on the inner surface of the window glass is removed to some extent by the demisting operation Moreover, fogging can be completely removed by this demisting operation Y. Note that even if the demist switch 26 continues to be turned on after the demist switch 26 is turned on during driving of the automobile, only the demist operation Y is performed thereafter by the AND element 30. As a result, dehumidification has been carried out to some extent by the demisting operation X, and henceforth, the fogging can be sufficiently removed only by the demisting operation Y, so that fluctuations in air conditioning can be suppressed more effectively.

As explained above, according to the present invention, the control device 18 is configured to control the control equipment constituting the vehicle air conditioner to perform the demisting operation simply by operating the demisting switch, so that the occupant can There is no need to individually control each control device to perform the demisting operation, and therefore operational safety can be ensured. In addition, during low-temperature periods when the outside air temperature is lower than the set temperature _t1 , the compressor is stopped and the demisting operation is performed, which reduces the load on the engine that drives the compressor and protects the compressor. can. In addition, the demisting capacity is reduced after the set time has elapsed, which solves the problem of the air conditioning condition changing drastically based on the demisting operation, causing discomfort to the passengers. It is possible to save labor.

[Brief explanation of drawings]

1 and 2 are simplified configuration diagrams and block diagrams showing one embodiment of a demist control method in a vehicle air conditioner according to the present invention, and FIG. 3 shows a demist control method in a vehicle air conditioner according to the present invention. This is a flowchart for explaining the operation. 1...Vehicle air conditioner, 2...Duct, 3
...Inside/outside air switching door, 4...Blower, 5...Evaporator, 6...Heater core, 7...Air mix door, 8, 9...Mode switching door, 18...Control device, 19...Temperature setting device, 21 ...Outside air temperature sensor, 22...Blowout mode setting section, 23...
Inside/outside air switching setting section, 24... Cooler control switch, 25... Blower rotation speed setting section, 26... Demist switch, 27... Timer, 29, 30...
...and element.

Claims (1)

[Claims] 1. Operates based on a signal from a demist switch to operate a blower for introducing inside and outside air, a compressor, an air mix door for adjusting the mixing ratio of warm air and cold air, a blowout mode switching door, and an inside and outside air switching door. In a vehicle air conditioner equipped with a control device, an outside air temperature is compared with a first set temperature, and when the outside air temperature is lower than the first set temperature, the rotational speed of the blower is set to a high speed, and the compressor is operated. stop,
Set the blowout mode switching door to defrost mode,
The inside/outside air switching door is set to outside air introduction mode to perform demisting operation A, and when the outside air temperature is higher than the first set temperature, the fan rotation speed is set to high speed and the compressor is operated to perform demisting operation X.
A method for controlling demisting in a vehicle air conditioner, characterized in that the demisting operation A or the demisting operation 2. A demist control method in a vehicle air conditioner according to claim 1, wherein the air mix door is controlled to increase the mixing ratio of warm air by the air mix door when the compressor is operated. 3. When the outside air temperature is higher than the first set temperature, the rotational speed of the blower is reduced after a set time has elapsed after the demisting operation X is performed, and at this time, the outside air switching door is set in the outside air introduction mode. A demist control method in a vehicle air conditioner according to scope 1. 4 After performing the demisting operation A, the rotation speed of the blower is decelerated after the set time has elapsed, and at this time, air is blown out to the feet, and the outside temperature and the first
Claim 1, wherein the rotation speed of the blower is increased when the outside air temperature is lower than the second set temperature than when it is higher than the second set temperature by comparing the set temperature with a second set temperature lower than the set temperature. The demist control method in the vehicle air conditioner described above.