JPH0235528Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention is a demist control system for an automobile air conditioner that dehumidifies the interior of the vehicle by driving the air conditioner in a demist mode according to factors that change the humidity inside the vehicle. Regarding equipment.

(Prior art) A conventional demist control device detects the humidity on the inner surface of a window glass using a dew condensation sensor, etc., and automatically switches the air conditioner to demist if the detected value is greater than a preset dew condensation judgment value. The system is operated according to the mode to prevent fogging of the window glass.

(Problem that the invention aims to solve) However, the humidity in the vehicle interior that causes fogging on the window glass is caused by the increase in humidity caused by the breathing and sweating of the passengers, so it is largely affected by the number of passengers. . Furthermore, depending on the season, the outside air may have higher humidity than the inside of the vehicle, so it is also affected by whether the air introduction mode is outside air or inside air. Conventionally, an invention disclosed in Japanese Patent Application Laid-open No. 54-333 has been proposed as a system for detecting the number of passengers to achieve air conditioning, and an invention disclosed in Japanese Patent Application Laid-open No. 189625/1989 has been proposed as an invention for achieving air conditioning using various sensors.
Although inventions such as No. 6060-248422 and No. 61-92908 have been disclosed, in the conventional demist control device in which the dew condensation judgment value of the humidity on the window glass is set to a constant value, However, the dew condensation state is determined only after the window glass becomes foggy, and it is difficult to reliably prevent the window glass from fogging up.

(Means for solving the problem) Therefore, the purpose of this invention is to prevent the occurrence of fogging on the window glass by making the dew condensation judgment value variable according to the factors that change the humidity inside the vehicle. .

The demist control device of the present invention has an overall configuration as shown in FIG. 1, which includes a humidity detection means 1 for detecting the humidity in the vehicle interior, a humidity change factor detection means 2 for detecting the humidity change factor in the vehicle interior, and A variable means 3 changes a preset condensation judgment value in the vehicle interior based on detection data from the detection means 2; and a determining means 4 that compares the humidity data with the humidity data and operates the air conditioner 11 in a demist mode when the humidity data is larger than the dew condensation determination value. Here, "based on detection data from the humidity change factor detection means 2" means based on a detection signal from a passenger number sensor that detects the number of passengers or an introduction mode sensor that detects whether the air conditioner is introducing outside air or inside air. It means.

(Function) Therefore, since the dew condensation determination value changes in accordance with the factors that generate humidity in the vehicle interior, for example, when the number of passengers increases, the dew condensation determination value is lowered.
The air conditioner 11 is operated in the demist mode before the humidity detecting means 1 detects the dew condensation state, so that the occurrence of dew condensation on the window glass can be prevented.

(Example) An example of the present invention will be described below based on the drawings.

FIG. 2 shows a schematic configuration of the automobile air conditioner 11 and its control circuit 10. As shown in FIG. First, to explain the air conditioner, the duct 12 has an inside air inlet 13 and an outside air inlet 14 on the most upstream side, and in order from the upstream side, an intake door 15, a blower 16, an evaporator 17, a mixer door 18, and a heater core 19.
A vent outlet 21 and a heat outlet 22 communicating with the vehicle interior 20 are provided on the most downstream side, and the defrost outlet 23 has a door 24 for mode switching.
25 are provided.

The intake door 15 is driven by a motor actuator 33 to adjust the ratio of outside air to vehicle interior air in the intake air. The blower 16 is operated by a drive circuit 35 and draws air into the duct 12 through the intake door 15. The evaporator 17 constitutes a cooler 30 together with a compressor 26 for compressing and circulating refrigerant, a condenser 27, a receiver tank 28 and an expansion valve 29, and is driven via a magnetic clutch 32 by a pulley 31 to which engine power is transmitted. Air introduced by the blower 16 passes through this evaporator 17 .

Furthermore, engine cooling water is introduced into the heater core 19, thereby heating the air that has passed through the evaporator 17. The ratio of air passing through the heater core 19 is set by the opening degree of the mix door 18, which is driven by a motor actuator 37. The mode switching doors 24 and 25 are driven by a motor actuator 39, and include a vent outlet 21 and a heat outlet 2.
2. Select the defrost outlet 23 and send out the conditioned air into the passenger compartment 20.

Furthermore, an evaporator humidity sensor 4 detects the humidity of the air at point A that has passed through the evaporator 17.
1. A potentiometer 42 that detects the opening degree of the mixer door 18, a dew condensation sensor (humidity detection means) 43 that detects the humidity on the inner surface of the window glass in the passenger compartment 20, and an occupant number sensor (humidity change factor detection) that detects the number of occupants. Means) 44, an introduction mode sensor 45 that detects mode switching of the intake door 15 between introducing outside air and introducing inside air, and a solar radiation sensor 4 that detects sunny conditions.
6. A detection signal from an outside air humidity sensor 47 or the like that detects outside air humidity is input to the control circuit 12 via the A/D converter 50. In the embodiment, the number-of-occupants sensor 44 is constituted by a pressure-sensitive switch provided at each seat. In addition, the number of occupants sensor 44
Alternatively, an infrared sensor or the like may be used.

The control circuit 10 includes an I/O port, a CPU, a ROM,
The microcomputer is comprised of a microcomputer having RAM and the like, and the variable means for varying the dew condensation determination value and the discriminating means for determining the condensation state are constituted by the microcomputer. Based on each data input from the A/D converter 50, the control circuit 10 determines judgment criteria corresponding to each humidity state, and controls the drive circuit 34 to adjust the opening degree of the intake door 15 and the drive circuit. 35 to control the amount of air blown by the blower 16, control the drive circuit 36 to control the operation rate of the cooler 30 via the magnetic clutch 32, and drive circuit 38.
controls the opening degree of the mixer door 18, and further controls the drive circuit 40 to change the mode switching doors 24, 2.
5 to perform demist control to dehumidify the interior of the vehicle compartment 20 in the demist mode.

Next, demist control of the air conditioner will be explained based on the flowchart shown in FIG. Note that P ₀ to _{P 4} in the figure indicate each step.

First, when the operation switch of the air conditioner is turned on, demist control is started (Po), and after the initial settings are made in step _P1 , each data, that is, the mode switching of the intake door 15 is detected in step _P2 . introduction mode sensor 45, vehicle interior 2
Each data is read from a dew condensation sensor 43 that detects humidity within 0 and an occupant number sensor 44 that detects the number of occupants.

In step _P3 , the current humidity data M in the vehicle interior 20 is higher than the preset sunny judgment value _H0 .
is small. Both H ₀ and M are expressed as relative humidity, and H ₀ is always set at 40% as shown in FIG. Therefore, the steps
If M<H ₀ at _P3 , the demist control of the air conditioner is not performed and the process returns to step _P2 .

If M<H ₀ is not found in step _P3 , it is assumed that the state is cloudy and the process proceeds to step _P4 , where it is determined whether to introduce outside air or inside air based on the data from the introduction mode sensor 45. In the case of internal air introduction, the respective dew condensation judgment values F ₀ and R ₀ are determined in step P ₅ and in step P ₆ in the case of inside air introduction. These dew condensation determination values F ₀ and R ₀ are stored in advance in a memory map as values corresponding to the number of passengers, as shown in FIG.

Next, in step _P7 , it is determined whether the humidity data M when outside air is introduced is smaller than the dew condensation judgment value _F0 , and if M> _F0 , the air conditioner is set to demist mode in step _P8 . Demist control is performed, and then the process returns to step _P2 and repeats this series of processing until M< _H0 , that is, the humidity M reaches the clear judgment value _H0 =40% in step _P3 . If M> _F0 is not satisfied in step _P7 , the process returns to step _P2 without performing demist control.

Also, in step _P9 , humidity data M
>R ₀ is determined, and if M>R ₀ , demist control is performed in the same way as above, and if M>R ₀ , demist control is not performed and the process returns to step _P2 .

Therefore, in the case of the above-mentioned configuration, in addition to the humidity data M inside the vehicle interior 20, the number of passengers and data on whether outside air or inside air is introduced, which are other causes of humidity generation inside the vehicle interior 20, are required. Demist control is carried out taking this into account, and the dew condensation judgment value of the humidity data M is made variable depending on the number of occupants and the form of air introduction, so detailed demist control is carried out according to the situation inside the vehicle compartment 20 and the air intake state. This makes it possible to prevent condensation from forming on window glass. Further, since demist control is not performed more than necessary, it is possible to save power. Note that the humidity change factor is not limited to the number of passengers and the form of air introduction, but the condensation determination value may be varied by taking into account weather conditions, outside temperature, etc., and the same effect can also be obtained by this. .

(Effects of the invention) As explained above, the invention includes a humidity detection means for detecting the humidity on the inner surface of the window glass inside the vehicle,
In a demist control device for an automotive air conditioner that drives and controls an air conditioner in a demist mode that dehumidifies a vehicle interior when the detected value from the humidity detection means exceeds a preset dew condensation determination value, the humidity inside the vehicle interior is A humidity change factor detection means for detecting a change factor is provided, and a variable means is provided for varying the dew condensation judgment value based on a detection signal from the humidity change factor detection means. By making the value variable according to the number of occupants and the state of indoor/outside air intake, which are factors that cause humidity, it is possible to perform fine-grained demist control according to the cabin conditions, reliably preventing the occurrence of condensation on the window glass. This makes it possible to save power.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of the present invention, Figs. 2 to 4 show an embodiment of the invention, Fig. 2 is a schematic configuration diagram showing an air conditioner and its control circuit, and Fig. 3 is a demist control diagram. A flowchart outlining the process;
FIG. 4 is a diagram illustrating each dew condensation determination value. 1,43...humidity detection means (condensation sensor), 2,
44, 47... Humidity change factor detection means (occupant number introduction mode sensor), 3... Variable means, 11... Air conditioner, 20... Vehicle interior, F ₀ , R ₀ ... Condensation determination value.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) The vehicle is equipped with a humidity detection means for detecting the humidity on the inner surface of the window glass inside the vehicle, and when the detected value from the humidity detection means exceeds a preset dew condensation determination value, In a demist control device for an automobile air conditioner that drives and controls an air conditioner in a demist mode that performs indoor dehumidification, it is possible to detect a A demist control device for an automobile air conditioner, characterized in that a variable means for varying the dew condensation determination value based on a detection signal is provided. (2) The demist control device for an automobile air conditioner according to claim 1, wherein the number of occupants sensor is a pressure-sensitive switch. (3) The demist control device for an automobile air conditioner according to claim 1, wherein the number of occupants sensor is an infrared switch.