JPH0375834B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for controlling the heater output of a road moisture detector used in road snow melting equipment to detect snow accumulation or wet conditions on the road surface. It is.

(Prior art) A road moisture detector that detects snow accumulation or wet conditions on the road surface in road snow melting equipment has a heater stored inside the detector, and a voltage is applied to the heater to remove snow accumulation or ice on the road surface. The snow is melted into water, and the resistance between the electrodes of the detector, which changes depending on the presence or absence of water, is detected to determine whether there is snow on the road surface or whether it is wet or not.

(Problems with conventional technology) The conventional road surface detection method had the following problems.

(1) Since the voltage applied to the heater is always constant, the heater always heats with the same output even if the snow or wetness of the road surface changes. For this reason, the detection part may become hot due to changes in the outside temperature, or the heat source supply to the snow melting equipment on the road surface may overlap, causing the road surface to locally become hotter than other parts, resulting in a partially dry state. It was difficult to accurately detect the wet state. Therefore, the control of the snow melting heater output based on the detection result becomes insufficient, and the performance of the snow melting equipment deteriorates.

(2) To solve these problems, it is possible to insert a contact like a thermostat or a temperature sensor into the moisture detector.
Since the moisture detector is buried in the road surface, doing so would complicate the wiring and be impractical.

(Object of the Invention) An object of the present invention is to provide a heater control method for a road surface moisture detector that can accurately detect the snow accumulation and wetness of the road surface, and furthermore to provide highly accurate snow melting equipment. .

(Means for solving the problem) As shown in the figure, the method for controlling the heater output of the road moisture detector of the present invention divides the outside air temperature into predetermined temperature ranges (1 to n), and The relationship between the temperature and the heater output of the road moisture detector 2 (for example, the heater output decreases as the outside temperature increases) is stored in the storage unit 8 in several ways as outside temperature data, and the presence or absence of moisture detected by the road moisture detector 2 is stored as outside temperature data. and the heater output of the same detector (for example, the output decreases when it is wet) is stored in the storage unit 8 as road surface data,
The relationship between whether or not the snow melting heater 3 is in operation and the heater output of the road surface moisture detector 2 (for example, the heater output decreases while the snow melting heater is in operation) is stored in the storage unit 8 as operation data, and the outside temperature measuring unit 4 The outside temperature is measured, and the outside temperature data of the temperature category to which the outside air temperature corresponds, the road surface data based on the presence or absence of road surface moisture detected by the road surface moisture detector 2, and the snow melting heater 3
The heater output of the road surface moisture detector 2 is determined from the operation data based on whether or not the vehicle is being operated, and the heater output is controlled.

(Operation of the Invention) In the diagram of the present invention, when the outside temperature is detected by the outside temperature sensor 5, the outside temperature determiner 6 determines which temperature category from 1 to n the outside temperature corresponds to, and the corresponding temperature category is determined. The signal is input to the determination circuit 7.

When road surface moisture is detected by the road surface moisture detector 2 shown in the figure, a determination signal of YES or NO is input from the moisture determination section 9 to the determination circuit 7.

When the illustrated snow melting heater operation determination unit 10 detects whether or not the snow melting heater 3 is being operated, an ON or OFF determination signal is input from the operation determination unit 10 to the determination circuit 7.

When each signal is input to the determination circuit 7, among the various data stored in the memory 8, data corresponding to each input is input to the determination circuit 7,
The appropriate output of the heater of the road moisture detector 2 is determined based on these data, and the heater of the road moisture detector 2 is controlled based on the output.

The determination method in the determination circuit 7 is, for example, as follows.

When the road moisture detector 2 detects moisture, it means that the snow or ice on the road has already melted.
There is no need to further melt snow or ice using the heater of the detector 2. Therefore, in this case, the heater output is determined to be low.

When the snow melting heater is operating, it has already been detected that there is snow or ice on the road surface, so the detector 2's heater melts any more snow or ice and detects the wetness of the road surface. There's no need to. Therefore, in this case, the heater output of the detector 2 is determined to be even lower.

(Example) The figure shows an example of the present invention. 4 in the figure is an outside air temperature measuring section. This is composed of an outside air temperature sensor 5 and an outside air temperature determiner 6. The outside air temperature sensor 5 detects outside air temperature. The outside air temperature determiner 6 is for determining which temperature category from 1 to n the temperature detected by the outside air temperature sensor 4 belongs to.

2 in the figure is a road surface moisture detector, which has a built-in heater (not shown) that melts the snow and ice accumulated on the detection part of the road surface and turns it into water. It detects the degree of road surface wetness based on the amount and amount of wetness. Reference numeral 9 denotes a moisture determining section, which determines whether the road surface is wet (YES, NO) based on the detection result of the road surface moisture detector 2.

3 in the figure is a snow melting heater, which melts snow on the road surface. 10 is a snow melting heater operation determination unit, which determines whether the snow melting heater is operating (ON,
OFF).

Reference numeral 8 denotes a storage section, in which three types of data are stored. One is several types of outside temperature data showing the relationship between the temperature of each temperature category 1 to n and the heater output of the road surface moisture detector 2 (for example, the heater output decreases as the outside air temperature increases). This is road surface data that shows the relationship between the presence or absence of moisture detected by the moisture detector 2 and the heater output of the same detector (for example, the output decreases when it is wet), and the other is whether or not the snow melting heater 3 is operating. and road moisture detector 2
This is operational data showing the relationship between the temperature and the heater output (for example, the heater output decreases while the snow melting heater is in operation).

7 is a determination circuit, and when signals are inputted to this circuit 7 from the temperature measurement section 4, the moisture determination section 9, and the snow melting heater operation determination section 10, various kinds of signals are inputted from the storage section 8 according to the respective inputs. Data is input, and the optimal output of the heater of the road surface moisture detector 2 is determined based on the input data, and the heater output is set.

The control method of the present invention uses a device with a program function and a timer function such as a micro sequencer that is easily available these days, an outside temperature determiner, a moisture determiner,
This can be easily realized by combining a solid-state relay, etc.

(Effects of the Invention) The method for controlling the heater output of a road moisture detector according to the present invention has the following effects.

(1) The optimal output of the heater of the road surface moisture detector 2 is selected depending on the outside temperature condition, the presence or absence of wetness of the road surface, and the operating status of the snow melting heater 3. This prevents localized high temperatures from drying out, making it possible to accurately detect the wet state.

(2) Instead of using the outside air temperature detected by the road moisture detector as it is, the outside air temperature measuring section 2
It is determined which of the temperature categories 1 to n the outside air temperature measured by is applied to, and the outside temperature data of the applicable temperature category is used.
The heater output of the road surface moisture detector 2 can be controlled accurately, and as a result, highly accurate snow melting equipment can be provided.

(3) Since there is no need to include a thermostat or a temperature sensor in the road moisture detector 2, the configuration is simple and it is easy to put it into practical use.

[Brief explanation of drawings]

The figure is an explanatory diagram of an embodiment of the control method of the present invention. 1 to n are temperature classifications, 2 is a road surface moisture detector, 3 is a snow melting heater, and 4 is an outside temperature measurement unit.

Claims (1)

[Claims] 1 Divide the outside air temperature into predetermined temperature ranges, store several relationships between the temperature of each of these classifications and the heater output of the road surface moisture detector as outside temperature data, and use the same method as the presence or absence of moisture detected by the road surface moisture detector. The relationship between the heater output of the detector and the heater output is stored as road surface data, the relationship between whether or not the snow melting heater is in operation and the heater output of the road surface moisture detector is stored as operating data, and the outside temperature is measured by the outside air temperature measuring section. The heater of the road surface moisture detector is calculated based on the outside temperature data of the temperature category to which the outside air temperature corresponds, the road surface data based on the presence or absence of road surface moisture detected by the road surface moisture detector, and the operation data based on the operation of the snow melting heater. A method for controlling heater output of a road surface moisture detector, characterized in that the output is determined and the same output is controlled.