JPS59149810A - Car air-conditioner - Google Patents

Abstract

PURPOSE:To improve comfortability by deciding frost from a window glass frost sensor signal then setting the air-conditioner to frost removal mode and holding this mode when the outer air humidity is higher than setting level. CONSTITUTION:A flag setting circuit 17 in a frost removal controller 6 is reset upon turning on of ignition switch. Occurrence of frost on window is detected in decision circuit 20 by a signal from a frost sensor 7 to provide a signal through a selection circuit 8 to a frost removal command circuit 11. Consequently a frost removal circuit 13 is functioned through a selection circuit 12 to operate the air-conditioner controller 5 in frost removal mode. At the same time, outer air humidity 19 is taken in and compared with setting level in humidity decision circuit 18, and if it is higher than setting level H signal is provided to the terminal 10 of selection circuit 8 thus to control the frost removal setting circuits 13, 14 to hold frost removal mode. With such arrangement, comfortability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioner for a vehicle, and particularly to a device for removing fog generated on the inner surface of a window glass.

Conventionally, fogging on the inner surface of a vehicle's window glass is detected by a dew condensation sensor or a humidity sensor that detects the humidity of the air inside the vehicle, and the inside/outside air switching door of the vehicle air conditioner is controlled to direct dry outside air into the vehicle interior. A device has been proposed that can be introduced into the cloud to clear up cloudy weather.
No. 3409).

However, with a device like this that detects the cause of fogging in the vehicle interior and clears it, as long as the cause of fogging, such as rain, exists outside the vehicle interior, the device will prevent the fogging from occurring even if it is cleared once. occurs again, and the vehicle air conditioner is set again to a mode that clears the fog, for example, the inside/outside air switching door is set to the outside air introduction mode, which ultimately causes a hunting condition, causing airflow changes and making driving difficult. This has disadvantages in that the air conditioner becomes difficult to move, and the air conditioning is obstructed, resulting in a loss of comfort.

An object of the present invention is to eliminate the above drawbacks by controlling a vehicle air conditioner based not only on the factors that cause fogging inside the vehicle interior but also on the factors that cause fogging outside the vehicle interior. This will be explained in detail using examples.

FIG. 1 is a block diagram showing an embodiment of a vehicle air conditioner according to the present invention, in which 1 is a temperature setting device 2.
set temperature TD, vehicle interior temperature tr detected by the inside air sensor 3, and outside air temperature ta detected by the outside air sensor 4.
This is an air conditioning control device that controls the air conditioning controller 5 based on the following. The air conditioning controller 5 is comprised of an inside/outside air switching door, a compressor for cooling the evaporator, a blower for introducing inside and outside air, a heater core, a mode switching door, etc. It operates to set the temperature of the blown air to the set temperature TD of the temperature setting device 2.

Reference numeral 6 denotes a defogging control device, which includes a fogging determination circuit 20 that determines the magnitude of the output signal tm of a dew condensation sensor 7 provided on the inner surface of the window glass to determine whether or not fogging has occurred, and controls the selection circuit 8. are doing. This judgment circuit 20 selects and outputs the signal H (high level) supplied to the terminal 9 by the selection circuit 8 when it is cloudy, and outputs it from the terminal 1 when it is sunny.
Control is performed so that the signal supplied to 0 is selected and output.

The output signal from the selection circuit 8 is the defogging command circuit 11.
is supplied to The output from the defogging command circuit 11 is supplied via a selection circuit 12 to a defogging setting circuit 13 in the repeat mode or to a defogging setting circuit 14 in the heater mode.

The defogging setting circuit 13 operates in the cooler mode when the outside air temperature ta is high, and drives the compressor that constitutes the air conditioning controller 5, and controls the inside/outside air switching door to introduce a portion of outside air to cool the inside of the vehicle. It works to reduce absolute humidity and clear cloudy weather. The defogging setting circuit 14 operates in the heater mode when the outside air temperature ta is low, and increases the rotational speed of the blower, sets the inside/outside air switching door to the outside air introduction mode, and sets the mode switching door to control the blowing direction. Set the defrost blowing mode, that is, the mode in which air is blown out onto the inner surface of the window glass. The selection circuit 12 is controlled by an outside air temperature determination circuit 15, and this outside air temperature determination circuit 15 receives information from the defrosting command circuit 11 when the outside air temperature ta is high and the air conditioner controller 5 operates in cooler mode. The signal is supplied to the defogging setting circuit 13 side, and when the outside temperature ta is low and the air conditioning controller 5 operates in the heater mode, the signal from the defogging command circuit 11 is supplied to the defogging setting circuit 14. control so that

17 is a flag setting circuit that is set by the output signal from the defogging command circuit 11 and latches an H signal;
The output signal of this flag setting circuit 17 is transmitted to the humidity judgment circuit 18.
is input. This humidity determination circuit 18 is operated by the H signal from this flag setting circuit 17, and compares and determines the humidity detected by the humidity sensor 19 that detects the humidity outside the automobile with a set level, and determines whether the humidity is at the set level. In this case, an H signal is supplied to the terminal 10 of the selection circuit 8, and when the level is below the set level, a reset signal is output to the flag setting circuit 17 to reset the flag setting circuit 17.

Normally, in the case of rainy weather, the humidity of the outside air is high and fogging tends to occur on the inner surface of the window glass, so that the humidity determination circuit 18 outputs an H signal. Note that the sensor 19 is attached to, for example, the body panel of an automobile or the inner surface of a window glass.

The operation of the vehicle air conditioner 5-device according to the present invention having the above configuration will be explained below using the flowchart shown in FIG. First, the air conditioning control device 1 has a temperature setting device 2.
The air conditioning controller 5 is controlled based on the set temperature TD, the hot water temperature tr in the vehicle interior, etc. to set the temperature in the vehicle interior to a comfortable temperature. In other words, normal control is performed.

The flag setting circuit 17 of the defogging control device 6 is set in a reset state in advance when the ignition switch is turned on.

Here, when fogging occurs on the inner surface of the window glass, the fogging determination circuit 20 detects this and controls the selection circuit 8.
The H signal supplied to the terminal 9 of the fog removal command circuit 11
control so that it is output to . As a result, the defogging command circuit 11 operates, and a signal from the command circuit 11 is supplied to the selection circuit 12. On the other hand, if the outside air temperature ta is high, the outside air temperature determination circuit 15 causes the selection circuit 12 to operate in the illustrated state, that is, so that the output signal from the defogging command circuit 11 is supplied to the defogging setting circuit 13. Therefore, the defogging setting circuit 13 operates to turn on the compressor constituting the air conditioning controller 5, and sets the inside/outside air switching door to a mode in which a portion of the outside air is introduced, thereby lowering the absolute humidity inside the vehicle interior and eliminating fogging. clear up If the outside air temperatures t and a are low, the outside air temperature determination circuit 15 controls the selection circuit 12 so that the output signal from the defogging command circuit 11 is transmitted to the defogging setting circuit 14.
The defogging setting circuit 1
4 operates to increase the speed of the blower of the air conditioning controller 5, set the inside/outside air switching door to the outside air introduction mode, and set the mode switching door to the defrost blowing mode to blow warm air onto the inner surface of the window glass to clear the fog.

When such a defogging operation is performed, at the same time, the flag setting circuit 17 is set by the defogging command circuit 11, and its output signal becomes H.

On the other hand, when the fog on the inner surface of the window glass clears with the above operation, the fogging determination circuit 20 controls the selection circuit 8 to switch its movable contact to the terminal 10 side, and the output signal from the humidity determination circuit 18 is transmitted to the fog removal command circuit 11. It operates so that it is output to . Since the flag setting circuit 17 outputs an H signal, the humidity determination circuit 18 is driven, and the humidity determination circuit 18 outputs a signal to the terminal 10 of the selection circuit when the humidity outside the vehicle is high such as on rainy days and there is a factor causing fogging. Outputs an H signal. Therefore, the H signal is input to the defogging command circuit 11, and based on this, the defogging setting circuit 13 or the defogging setting circuit 14 is controlled to maintain the air conditioner controller 5 in a mode for defogging. do.

On the other hand, when the humidity outside the vehicle is below the set level, an L (low level) signal is output to the input terminal 10 of the selection circuit 8, so the defogging command circuit 11 does not operate. Also, at this time, the flag setting circuit 17 is reset to L. On the other hand, if fogging has not occurred on the inner surface of the window glass in advance, the defogging command circuit 11 does not work, and the output signal of the flag setting circuit 17 is L, the humidity determination circuit 18 does not work, so the terminal of the selection circuit 8 Since the L signal is supplied to 10, the defogging command circuit 11 does not operate. As a result, the air conditioning controller 5 does not perform the defogging operation.

According to the present invention, when fogging occurs on the inner surface of the window glass, the air conditioning controller 5 is driven in a mode that removes the fogging on the inner surface of the window glass, so that the fogging on the inner surface of the window glass can be removed. Can be done.

If there is an external factor that causes fogging on the inner surface of the window glass, that is, when the humidity outside the vehicle is higher than the set level, the air conditioning controller 5 is maintained in a mode that removes fogging, so that the inner surface of the window glass is again fogged. Cloudiness will no longer occur. Therefore, since the defogging mode is not set intermittently, changes in airflow and generation of abnormal noises do not occur, and wear and tear on the switch portion of the air conditioning control equipment can be reduced.

In the present invention, the defogging control device 6 may be configured using a microcomputer, and this microcomputer may be provided with functions such as the humidity determination circuit 18.

Further, the humidity sensor 19 may be provided at an air inlet in the vehicle interior as long as it detects the relative humidity of the outside air entering the vehicle interior. Alternatively, relative humidity may be detected by detecting absolute humidity using the humidity sensor 19 and calculating this data with the magnitude of the outside air temperature.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a nineteenth embodiment of a vehicle air conditioner according to the present invention, and FIG. 2 is a flow chart for explaining its operation. 1... Air conditioning control device, 5... Air conditioning control machine, 6...
Defogging control device, 7...fogging determination circuit, 8.12.
...Selection circuit, 11...Fog removal command circuit, 13.1
4...Fog removal setting circuit, 15...Outside air temperature determination circuit, 18...Humidity determination circuit. Patent applicant: Agent of Diesel Kiki Co., Ltd.
Patent Attorney Jun Miyazono -10-

Claims (1)

[Claims] a determining means for determining fogging based on a signal from a dew condensation sensor provided on an inner surface of a window glass, a setting means for setting an air conditioning controller to a defogging mode based on a signal from the determining means, and the air conditioning controller When the air conditioner is set to the defogging mode, a humidity sensor detects the humidity of the outside air, and when the humidity is above a set level, the air conditioning controller is maintained in the defogging mode. Air conditioner for vehicles.