JPH0542696Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a device for preventing fogging of window glass, etc., and in particular detects the steepness of change in fogging of the window glass of automobiles, etc. The present invention relates to a fogging prevention device for window glass, etc., which prevents fogging by incorporating predictive control according to the weather conditions.

[Prior Art] Conventionally, the relative humidity, etc. in the interior of a vehicle, such as an automobile, has been detected, and a fog removal device has been driven when the relative humidity is a certain set value, for example, a certain percentage. 2. Description of the Related Art Anti-fogging devices for window glass and the like are known that control to prevent fogging due to moisture condensation on the window glass in advance and to secure the driver's visibility and ensure safe driving.

However, in the case of these conventional fog removal or prevention devices, even though the operation start conditions may change depending on various conditions such as outside air conditions and weather, control is simply based on absolute values such as relative humidity. Therefore, when the degree of change in relative humidity changes due to the opening and closing of doors and windows or the increase or decrease in the number of passengers, it is not possible to effectively follow or respond to the changes in relative humidity, and as a result, the window It may cause fogging on the glass, etc.
On the other hand, there was a problem in that energy was wasted in operating the air conditioner.

These problems will be explained in more detail with reference to several changes in relative humidity with respect to time shown in FIG. Figure 1 is a graph showing the relationship between time (minutes) and relative humidity (%).The relative humidity ranges from 5% to 10% lower than the fogging judgment value that determines that fogging actually occurs on window glass, etc.
Regarding how much time is required to transition to a lower relative humidity, consider several relative humidity change situations A,
B and C are shown.

As is clear from Figure 1, the time until the next cloudy judgment value arrives is different for each relative humidity change situation A, B, and C, which means that the subsequent cloudiness is naturally different. If the defogging drive control is started at the same time even though there is a change in relative humidity, there will be a difference in the actual demist state, and as a result, fogging will occur due to the discrepancy between the relative humidity and the demisting process. , or conversely, there are disadvantages such as excessive demisting.

As described above, the conventional fog removal apparatus cannot accurately perform fog removal, that is, fog prevention control, in accordance with the steepness of the change in relative humidity.

In addition, JP-A-61-60356 or JP-A-61
-91706, etc., but the former is a control that simply turns on and off the fog remover based on the temporal change in relative humidity, and the latter is a control that is proportional to the amount of cooling heat required in the vehicle interior, etc. It attempts to supply heat and requires complex control.

[Problems to be solved by the invention] The present invention was conceived in consideration of the above-mentioned problems, and focuses on the fact that the humidity in the interior of a car changes depending on various conditions, By predicting or determining cloudiness according to the cloudiness and by making it possible to take preventive measures according to the steepness of humidity changes based on the cloudiness determination, fogging due to moisture condensation on window glass can be prevented in advance. However, it is an object of the present invention to provide an anti-fogging device for window glass, etc., which is controlled so as to ensure the driver's field of view and ensure safe driving.

[Means for Solving the Problems] That is, the present invention determines the steepness of the humidity change, that is, the rate of the humidity change, controls the start of operation of the fog removal means, and also determines the relative humidity from a certain point to a certain point. This is an anti-fogging device for window glass, etc., which changes the starting point, operating method, and operating time of demist control in stages according to the rate of change.

[Function] When controlling a fog prevention device such as a window glass, the present invention calculates the gradient of humidity change by detecting the change in humidity per unit time or the time required to cause a certain amount of humidity change. By changing the intensity of the demist control in stages according to this gradient, for example, when the humidity change is sudden, as in the relative humidity change situation A shown in Figure 1, the intensity is strong, and conversely, the relative humidity control is By performing step-by-step control such as performing weak demisting when the change is gradual, such as in situation C, the step-by-step fog prevention function corresponding to the steepness described above can be exerted in an energy-efficient manner, and fog can be prevented accurately. You can do it like this.

More specifically, the relative humidity change situation A,
Change the magnitude of the humidity judgment value step by step in the order of B and C, and in the case of relative humidity change situation A, start demist control at a point far lower than the normal humidity judgment value, or set the operating condition as On/off control of the compressor of the refrigeration system of air conditioners,
Performs control such as changing the air outlet and air blowing amount. In addition, if the humidity change is gradual as in relative humidity change situation C, for example, the above-mentioned compressor should be turned on to perform the demisting process, or if the compressor cannot be turned on, the defrost outlet should be opened from the window etc. By changing the mode, for example from heat mode to heat/defrost mode, so that conditioned air can be applied to the inner surface, and by blowing out conditioned air for a shorter period of time compared to relative humidity change situation B, fogging can be eliminated. Remove or prevent fogging in advance.

[Example] Next, an example of the present invention will be described based on the drawings.

Fig. 2 schematically shows the structure of an automobile air conditioner with a demist function, which applies the fog prevention device for window glass etc. according to the present invention.This automobile air conditioner is equipped with a duct 1. An inside/outside air switching door 4 is provided between the inside air inlet 2 and the outside air inlet 3 on the upstream side of the duct 1.
The opening and closing of this internal/external air switching door 4 is controlled by a first motor actuator 5. Air from the inside air inlet 2 or the outside air inlet 3 is introduced into the duct 1 by a blower 6, and on the downstream side of the blower 6, the evaporator 7 of the cooler unit, the air mix door 8, the heater core 9 of the heater unit,
Mode switching doors 10 and 11 are provided.

The evaporator 7, together with a compressor 12, a condenser 13, a receiver 14, and an expansion valve 15, constitute the refrigeration cycle of the refrigeration system. The rotational force from an engine pulley 16 is transmitted to the compressor 12 via a magnetic clutch 17.

The air mix door 8 adjusts the mixing ratio of the cold air from the evaporator 7 and the warm air from the heater core 9, and is controlled by a second motor actuator 18. In conjunction with the opening and closing of the air mix door 8, the water tap 19 is opened and closed to adjust the heating amount of the heater core 9.

The mode switching doors 10, 11 are for adjusting the direction and amount of air blown out from the defrost outlet 20, the face outlet 21, and the foot outlet 22.
1 is controlled by a third motor actuator 23.

In addition, the control unit 2 as a control circuit
4 is the above-described first motor actuator 5,
It controls the second motor actuator 18, the third motor actuator 23, the blower motor 6a that drives the blower 6, and the magnetic clutch 17, and has an inside/outside air switching door control circuit 25 inside. , a blower control circuit 26, a compressor control circuit 27, an air mix door control circuit 28, and a mode switching door control circuit 29.

Furthermore, a vehicle interior humidity sensor 30 that detects the humidity inside the vehicle interior and an outside air temperature sensor 31 that detects the outside air temperature outside the vehicle interior are connected to this control unit 24, and signals from these sensors 30 and 31 are input. . Note that the signal from the vehicle interior humidity sensor 30 is used to detect the cloudy state of the window glass surface of the vehicle.

Furthermore, a vehicle interior temperature setting device 32 is connected to the control unit 24 for setting the temperature inside the vehicle interior.

The control unit 24 has a correction fixed value memory storing a correction fixed value K (described later, see FIG. 5) with respect to the steepness or change gradient of the humidity change based on the detection signal from the vehicle interior humidity sensor 30. 33, and a cloudy judgment humidity storage part 34 that stores the relationship between the corrected outside air temperature T (described later, see FIG. 6) corrected by the corrected fixed value K and the cloudy judgment humidity.

Next, demist control including anti-fogging processing in the automobile air conditioner configured as described above will be explained based on FIGS. 3 to 7.

First, the humidity control in the normal operating state is executed in a normal mode as shown in FIG. air-conditions in any mode that maintains the vehicle interior temperature set using the vehicle interior temperature setting device 32, etc.;
Heat/if the outside temperature is between 10℃ and -10℃
By setting the defrost (H/D) mode, that is, setting the air mix door 8 to full heat, setting the mode switching door 10 to the position indicated by the dotted line in FIG. The air is conditioned in a mode in which warm air is blown out from the defrost outlet 20 as well.

When the outside temperature is -10°C or lower, the defrost mode is set, that is, the air mix door 8 is set to full heat, and the mode switching door 10 is set to the second mode.
In addition, the mode switching door 11 is located at the position indicated by the dotted line in the figure.
By locating it at the dotted line position, a mode is activated in which warm air is blown out from the defrost outlet 20 toward the inner surface of the window glass.

However, in its normal operating state, the automotive air conditioner executes the normal mode control as described above, but when it enters the demist control flow as shown in the flowchart of FIG. If this occurs, the following controls will be executed.

That is, first in step S1, the relative humidity H detected by the vehicle interior humidity sensor 30 is
Detect the gradient ΔH/Δt of the time change. This is calculated as the amount of change in relative humidity with respect to the time shown in FIG.

In the next step S2, this gradient ΔH/
A correction fixed value K corresponding to Δt is determined from the graph of FIG. 5 showing data in the correction fixed value storage section 33 of the control unit 24. As shown in Figure 5, when the slope of the change in relative humidity is below a certain value, K is set to zero, but when it exceeds this certain value, the fixed correction value K is set to a larger value with a predetermined slope. do.

Next, in step S3, the outside temperature sensor 3
The corrected outside temperature T is obtained by subtracting K from the current outside temperature Tout according to 1. Therefore, the larger the gradient ΔH/Δt of the change in relative humidity, the smaller the corrected outside temperature T will be determined.

Then, in step S4, this corrected outside temperature T
Find out the judgment humidity at which to start the demisting process, that is, the cloudy judgment humidity Hon. This is obtained from the graph in FIG. 6 showing the data in the cloudy judgment value storage section 34 of the control unit 24, but it can be obtained by using the simplified broken line shown in the solid line in FIG. It can be determined by any arbitrary relationship, such as.

Next, in step S5, it is determined whether or not demisting is to be started, that is, whether the relative humidity H in the vehicle interior measured by the vehicle interior humidity sensor 30 is greater than the cloudy judgment humidity Hon. If the humidity inside the vehicle is lower than the cloudy judgment humidity Hon, this flow is exited as demist control is not required. If it is large, the process moves to step S6 to perform demist control, and as shown in FIG.
The degree of demisting is determined based on the size of the demist.

That is, when the timer time Δt is smaller than the first judgment time t1, the above-mentioned defrost control is performed to cope with the sudden humidity change (step
S7), when the timer time Δt is between the second judgment time t2 and the first judgment time t1 as determined in step S8, the heat/defrost control is performed (step S9), and the timer time Δt is between the second judgment time t2 and the first judgment time t1. When this happens, the normal mode control is executed (step S10). In other words, by changing the fog removal operation in stages, demisting is performed with an appropriate intensity depending on the steepness of each humidity change.

Next, in step S11, if the current outside temperature Tout is larger than the vehicle interior temperature set by the vehicle interior temperature setting device 32, step S11 is performed.
At step 12, the air conditioner mode of the refrigeration system is turned on and normal temperature control is performed. Next, in step S13, the air volume of the blower 6 is increased. Note that in step S11, the current outside temperature
If Tout is smaller than the vehicle interior temperature setting Tin, the process moves to step S13.

However, as shown in FIG. 7, when two values, such as the first judgment time t1 and second judgment time t2, are selected as values corresponding to the slope of relative humidity that serve as the reference for judgment, The anti-fogging control is performed in three stages as shown in Fig. 7, but if there is only one criterion for the judgment slope, the timer time Δt and, for example, only the first judgment time t1 are compared. Normally, priority is given to control in the normal mode shown in FIG. 3, and when the humidity is shorter than the humidity determination standard, that is, the first determination time t1, the next higher level cloud removal operation is performed. For example, when the heat/defrost (H/D) mode is being performed, the mode is shifted to the defrost mode, which has a higher fog removal intensity.

Of course, even if there are two judgment criteria, the first judgment time t1 and the second judgment time t2, as shown in Fig. 7, it is assumed that the upper heat/defrost control is simply performed, or it is performed in the normal mode. When there are two higher defrost control modes as in the case where the defrost control mode is set to two higher levels, it is also possible to perform control to shift to the two higher level defrost control modes.

In the present invention, in order to detect changes in relative humidity, sampling may be performed at regular time intervals and compared, or the average value of a given number of samplings at regular time intervals may be compared.

Furthermore, the control can be carried out by simply changing the starting point of the demisting process, without changing the operation of the inside/outside air switching door 3 and the compressor 12, without moving the air mix door 8, and without changing the blowing mode. You may do so.

Furthermore, as the humidity sensor, it is possible to use an optical humidity detection means, and it goes without saying that any humidity detection means may be employed, such as using a thermal balance means.

[Effects of the invention] As explained above, according to the invention, the rate of change in humidity is predicted and the degree of demist treatment is adjusted in stages, so that the degree of demisting treatment can be adjusted in stages before fogging actually occurs on window glass, etc. Not only can this be prevented in advance, but also demist control can be executed in accordance with each stage of humidity change rate, making it possible to realize efficient and simple control.

[Brief explanation of the drawing]

Fig. 1 is a graph showing the rate of change in relative humidity with respect to time, Fig. 2 is a schematic diagram of an automobile air conditioner equipped with an anti-fogging device for window glass, etc. according to an embodiment of the present invention, and Fig. 3 is a graph showing the rate of change in relative humidity with respect to time. Graph of air conditioning control in normal mode, Figure 4 is a flowchart of control, Figure 5 is a graph of correction fixed value K against gradient ΔH/Δt of change in relative humidity, Figure 6 is a graph of air conditioning control in normal mode. Same, cloudy judgment humidity for corrected outside temperature T
Hon's graph, FIG. 7, is a graph of demist control versus timer time Δt corresponding to changes in humidity. DESCRIPTION OF SYMBOLS 1...Duct, 2...Inside air inlet, 3...Outside air inlet, 4...Inside and outside air switching door, 5...First motor actuator, 6...Blower, 6a...
Blower motor, 7... Evaporator, 8... Air mix door, 9... Heater core, 10, 11...
...Mode switching door, 12...Compressor, 1
3... Capacitor, 14... Liquid receiver, 15... Expansion valve, 16... Engine pulley, 17... Magnetic clutch, 18... Second motor actuator, 19... Water cock, 20... ...Defrost outlet, 21...Face outlet, 22...
... Foot outlet, 23... Third motor actuator, 24... Control unit, 25...
...Inside/outside air switching door control circuit, 26...Blower control circuit, 27...Compressor control circuit, 28...
... Air mix door control circuit, 29 ... Mode switching door control circuit, 30 ... Vehicle interior humidity sensor,
31...Outside temperature sensor, 32...Interior temperature setting device, 33...Fixed value storage for correction, 34...Fogage judgment humidity storage, K...Fixed value for correction, Tout
...Current outside temperature, T...Corrected outside temperature, Tin...
Vehicle interior temperature setting, Hon...fog judgment humidity, H...
...Detected relative humidity, t1...First judgment time, t2...
Second judgment time, ΔH/Δt...gradient of relative humidity change, Δt...timer time according to relative humidity change ΔH, S1 to S13...steps.

Claims (1)

[Scope of Claim for Utility Model Registration] A device for preventing fogging of window glass, etc., which has a means for removing fog from window glass, etc., a humidity sensor that detects indoor humidity, and an outside temperature sensor that detects outdoor temperature, a correction fixed value storage unit for calculating the steepness of the humidity change based on the detection signal from the humidity sensor and further determining a correction fixed value according to the steepness of the humidity change; and the correction fixed value. and a cloudy judgment humidity storage unit for determining a cloudy judging humidity according to the corrected outside temperature calculated from Controlling the start of operation of the cloud removal means by comparison, and controlling the intensity of the demisting process by the cloud removal means to be changed in stages in accordance with the magnitude of the timer time for calculating the steepness. Anti-fogging device for window glass, etc., which has a control means to prevent fogging.