JPH0125693Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vehicle air conditioner, and particularly to a vehicle air conditioner equipped with fog removal control.

[Conventional technology]

Conventionally, a vehicle air conditioner includes an inside/outside air switching door 2 provided in a duct 1, a blower 3, a cooler 4, an air mix door 5, as shown in FIG.
It includes a heater 6, a mode switching door 7, a defrost outlet 8, a face outlet 9, and a foot outlet 10. The cooler 4 includes a compressor 11,
The condenser 12, receiver tank 13, and expansion valve 14 constitute a cooling cycle. The rotational force of the engine 15 is transmitted to the compressor 11 via a magnetic clutch 16.

17 is an A/D converter, which detects the temperature Tr detected by the inside air sensor 18 that detects the temperature inside the vehicle, the opening degree θ of the air mix door 5 detected by the position detection potentiometer 19, and the amount of solar radiation Ts detected by the solar radiation sensor 20. , the outside air temperature Ta detected by the outside air temperature sensor 21, the duct internal temperature Tm detected by the mode sensor 22, the set temperature T _D outputted from the temperature setting device 23, and the signal T _W outputted from the water temperature switch 50. It converts into each digital signal and outputs it to the control section 24.

The control unit 24 is composed of, for example, a microcomputer, and controls the switching circuit 25 and the actuator 2.
6, a compressor control means 29 that controls the magnetic clutch 16 via a drive circuit 28, and a blower 3 via a drive circuit 30.
a blower control means 31 for controlling the
2. Air mix door control means 34 that controls the air mix door 5 via the actuator 33
, a mode switching door control means 37 that controls the mode switching door 7 via a switching circuit 35 and an actuator 36, and each control means 27, 31, which calculates each data Tr, Ts, Ta, Tm, and _TD . 34 and 37
and calculation means for outputting each output. 39 is a manual switch for controlling the blower.

The compressor control means 29 controls the temperature inside the duct.
When Tm drops to a temperature level L ₁ (stored in the setting device 40) that is slightly higher than the freezing temperature of the cooler 4, the compressor 11 is turned off, and the temperature level L ₂ (memorized in the setting device 40) is set higher than the level L ₁ by the hysteresis width Y. The compressor 11 is turned on when the temperature rises to (memory), and the temperature of the cooler 4 is kept constant. Here, the hysteresis width Y is set to a constant value.

[Problem that the invention attempts to solve]

However, conventional vehicle air conditioners
As disclosed in JP-A-59-18014 or JP-A-59-14564, regarding the defogging control of window glass,
The fog removal control was performed by comparing the output of the dew condensation detection sensor attached to the window glass with a reference value, which is the fog judgment value that should be set in the fog removal mode.
When the compressor was turned on, the fog removal mode was set even though there was no fog, and when the compressor was turned off, the occurrence of fog could not be prevented due to insufficient dehumidifying ability. . This results in energy loss or reduced safety.

[Means for solving problems]

The present invention includes a compressor operating mode detecting means, and sets a cloud removal mode by providing a difference in a reference value serving as a clouding judgment value depending on whether the compressor operating mode is on or off.

This will prevent energy loss and improve safety.

[Effect]

When the compressor operation mode is on, the dehumidification capacity is sufficient, so a relatively high standard value is used to determine cloudiness, and when the compressor operation mode is off, a relatively low standard value is used to determine cloudiness. The defogging mode is set based on the results.

〔Example〕

FIG. 1 is a simplified configuration diagram showing an embodiment of a vehicle air conditioner according to the present invention, and the same parts as in FIG. 3 are denoted by the same reference numerals. In the figure, 50 is a dew condensation detection sensor attached to a window glass, 51 is compressor operation mode detection means for detecting whether the compressor 11 is in on/off mode, and 52 is a cloudiness determination value to be compared with the output of the dew condensation detection sensor 50. a first setting device for setting a first reference value _F1 ;
53 is a second setting device that also sets the second reference value F ₂ , and the second setting device 53 sets the second reference value F ₂
is set to a value lower than the first reference value _F1 . 54
55 is a reference value switching device that outputs a first reference value F ₁ when the compressor is in the on mode and outputs a second reference value F ₂ when the compressor is in the off mode, according to the output from the compressor operating mode detection means 51; This is a fog removal control section, and the first or second reference value F ₁ or F ₂ from this reference value switch 54 is
and the output of the previous dew condensation detection sensor 50, and outputs a cloud removal mode command to the control section 24. Upon receiving the fog removal mode command, the control unit 24
Set the defogging mode according to the outside temperature.

The operation of the above configuration will be explained using the flowchart shown in FIG. In step 101, it is determined whether the temperature detected by the outside air temperature sensor is higher than a design value, for example 5° C., and if it is, the process proceeds to step 102, where the compressor is turned on mode, and the process proceeds to step 103. In step 103, cloudiness is determined by comparing the first reference value F corresponding to the on mode with the output of the dew condensation detection sensor 50. If there is no cloudiness, the process proceeds to step 104 to turn off the compressor, and if there is cloudiness, the process proceeds to step 104. 1
05 and 106, the compressor is turned on, and the inside air introduction mode is set to become the fog removal mode. On the other hand, if the outside air temperature is determined to be less than 5° C. in step 101, the process proceeds to step 107 and the compressor is placed in off mode. In the next step 108, a second reference value _F1 lower than the first reference value F1 is determined.
Cloudy determination is performed by comparing the reference value F ₂ and the output of the dew condensation detection sensor 50. If there is no clouding, the process advances to step 109 and the cloud removal mode is canceled. If it is cloudy, go to steps 110-11
2, the fog removal mode, that is, the outside air introduction mode, the blower speed increase, and the defrost mode are set.

〔effect〕

As explained above, according to the present invention, differences are set in the fogging judgment value and reference value to be set in the fog removal mode depending on the on/off mode of the compressor, and the reference value is set higher in the on mode because the dehumidifying ability is high. Since the dehumidification ability is inferior in off mode, the reference value is set to a value closer to low humidity.
Since fogging is determined by comparing the output of each dew condensation detection sensor, on the one hand, unnecessary compressor operation can be avoided and energy can be saved, and on the other hand, fogging can be completely prevented from occurring, improving safe driving. improves.

[Brief explanation of the drawing]

FIG. 1 is a simplified configuration diagram showing an embodiment of a vehicle air conditioner according to the present invention, FIG. 2 is a flowchart explaining the operation of the same embodiment, and FIG. 3 is a simplified configuration diagram showing a conventional example. . 50... Condensation detection sensor, 51... Compressor operation mode detection means, 52... First setting device, 5
3...Second setter, 54...Reference value switch, 55
...Fog removal control section.

Claims (1)

[Scope of utility model registration request] At least a compressor control means that puts the compressor in an on mode when the temperature detected by an outside air temperature detection sensor is higher than a set value and puts the compressor in an off mode when it is lower than that, and an output of a condensation detection sensor attached to a window glass of the vehicle. In a vehicle air conditioner, the vehicle air conditioner is equipped with a fog removal control unit that compares F with a reference value F and sets a fog removal mode,
Compressor operation mode detection means for detecting an on-off mode of the compressor is provided, and the cloud removal control section detects a first compressor when the on mode is detected by the compressor operation mode detection means.
The reference value _F1 is compared with the output of the dew condensation detection sensor to determine the fog removal mode, and when the off mode is detected, the second reference value is lower than the first reference value _F1 .
A vehicle air conditioner characterized by having a fog removal mode compared to _F2 .