JPH0429429Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a snowfall detection device that utilizes the reflection of light, etc. on snow.

[Prior Art] Conventionally, in a case of this type, a projecting light projecting device is provided opposite to the top surface of the case, and a window is provided on the surface of the top surface of the case that is illuminated from the projecting device through a lens. A transparent plate is fitted to the window,
A snowfall detection device is proposed in Japanese Utility Model Application Publication No. 49-55085, in which a light receiver is provided inside the case and is illuminated by the light projector through the transparent plate.

[Problems to be solved by the invention] In the conventional technology, the lens on the projector side is exposed to the outside and comes in contact with the outside air, so if it is installed outdoors, the lens will become dirty and the light will not be received even though there is no snow. There is a problem that the device side cannot receive light and malfunction occurs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a snowfall detection device that can solve the above problems and prevent malfunctions due to dirt.

[Means for Solving the Problems] The present invention provides a light-transmitting plate on the same plane as a part of the lower part of the slope of the case, and directs the light-emitting part and the light-receiving part to the light-transmitting plate, so that a direct reflection type photoelectric switch can be operated. A heater for melting snow on the transparent plate is provided close to the back side of the transparent plate, and a snow stopper is installed at the lower part of the slope.

[Function] When snow accumulates on the transparent plate, the light beams emitted from the light projecting section are reflected by the snow and enter the light receiving section, allowing snow to be detected. The snow that was prevented from falling by the snow stopper plate is melted by the heater and flows down.

[Example] Next, a first example of the present invention will be described based on FIGS. 1 to 4.

Reference numeral 1 denotes a triangular, substantially sealed case having a slope 1a, and a transparent plate 1b is provided at a portion below the slope 1a, that is, below the center. The transparent plate 1b is attached to a window hole formed at the bottom of the slope 1a, and its upper surface is flush with the slope 1a. Further, a snow stopper plate 1c is erected at the lower end of the slope 1a, and side plates 1d and 1g are erected diagonally upward on both sides of the slope 1a to prevent snow a from being blown away by crosswinds.

Reference numeral 2 denotes a direct reflection type photoelectric switch which is placed close to the back side of the transparent plate 1b at an interval of 0 to 10 mm, preferably 3 to 5 mm. It has a light receiving section 2b made of a diode that receives the reflected light, and these light projecting section 2a and light receiving section 2b are directed toward the transparent plate 1b.

3 is a heater plate, which is provided integrally with the slope 1a.

Reference numeral 4 denotes a control device which operates the direct reflection type photoelectric switch 2, heater plate 3, etc. at every snowfall interval.

Reference numeral 5 denotes a snow melting device, which is started and stopped by a control device 4 that detects snow using a direct reflection type photoelectric switch 2.

In this embodiment, the snow is melted by sprinkling water using the pump 5a, but a heater, hot water, etc. may also be used.

Next, the operation and effect will be explained with reference to the explanatory diagram showing the time chart of FIG.

The power source of the direct reflection type photoelectric switch 2 is kept energized during the snowfall period.

In state A, that is, when snowfall is continuous, the direct reflection photoelectric switch 2 outputs an output signal at regular intervals. That is, the light beams emitted from the light projecting section 2a are transmitted through the transparent plate 1.
b, the snow is prevented from falling by the snow stopper plate 1c, and is reflected on the snow a located on the slope 1a, and the reflected light reaches the light receiving section 2b and detects the snow. Then, the heater plate 3 is activated by a signal from the direct reflection type photoelectric switch 2, and the snow a on the slope 1a melts and flows down. At the same time, the snow melting device 5 is operated.
Next, in state B, that is, when there is no snow, there is no snow on the slope 1a, so the direct reflection photoelectric switch 2
does not produce an output signal. That is, the light beams emitted from the light projecting section 2a are emitted upwardly from the transparent plate 1b and do not enter the light receiving section 2b. Therefore, since no output signal is output from the direct reflection type photoelectric switch 2, the heater plate 3 and the snow melting device 5 do not operate.

In conditions C and D, that is, when it snows intermittently, when snow falls on the slope 1a, the direct reflection photoelectric switch 2 detects the snow on the slope 1a, which is prevented from falling by the snow stopper plate 1c. , outputs an output signal in the same manner as above. As a result, the heater plate 3 is energized to melt and remove snow on the slope 1a, and the snow melting device 5 is activated.

FIG. 4 is an electrical circuit diagram of the control device 4 that performs the time chart shown in FIG.

By closing the switch 4c, the direct reflection type photoelectric switch 2 is energized and enters a standby state. Note that if the power source is a dedicated power supply device, power is supplied to the power supply device.

During snowfall, snow a accumulates on the slope 1a and is prevented from falling by the snow stopper plate 1c. Therefore, the contact 4d of the direct reflection type photoelectric switch 2
When is closed, relay 4f is activated. Note that 4e is a contact point of the timer 4a. When the relay 4f is activated, the contact 4g is closed, the timer 4a is activated, and the timer 4a is energized. Therefore, the snow melting device 5
The motor relay 4l closes and the pump 5a operates.

After the time set by the timer 4a, the holding contact 4i is opened and the pump 5a is stopped.

Also, when the contact 4j of the relay 4f closes, the timer 4b is activated, and the timer 4b energizes the heater plate 3 until the set time. After the set time of the timer 4b has elapsed, the holding circuit contact 4k opens and the energization to the heater plate 3 is terminated. In addition, the timer 4 for the snow melting device 5
It is desirable that the setting of a be longer than the timer 4b for the heater plate 3, but the setting is not limited thereto.

In this way, by starting the snow melting device 5, the pump 5
A is used to melt snow by sprinkling water. At the same time, the heater plate 3 is activated, and the snow a on the slope 1a is warmed and melted, and the snow a on the slope 1a flows downward by the surface flow. And snow a is slope 1a
It is left behind by the snow stopper plate 1c provided at the lower end.

As described above, by detecting snow a by placing the direct reflection type photoelectric switch 2 having the light projecting part 2a and the light receiving part 2b close to the back side of the diagonally installed transparent plate 1b,
The light projecting section 2a and the light receiving section 2b are not exposed to the outside air, so there is no risk of the light projecting section 2a and the light receiving section 2b getting dirty.

Furthermore, since the upper surface of the transparent plate 1b is flush with the slope 1a, that is, there are no unevenness on the slope 1a and the transparent plate 1b, the water melted by the heater plate 3 flows along the slope 1a. and transparent plate 1b
The dirt on the transparent plate 1b is always free of dirt, and malfunctions such as reflection of light beams from the light projector 2a due to the dirt can be prevented.

Furthermore, by providing the snow stopper plate 1c at the lower end of the slope 1a, the snow a will not slide down the slope 1a before the direct reflection type photoelectric switch 2 detects it, and the light transmission above the direct reflection type photoelectric switch 2 will be ensured. Part 1
Snow a is piled up on top b, reducing malfunctions even when there is little snow.

FIG. 5 shows a second embodiment of the present invention, in which the first embodiment
The same parts as in the embodiment are given the same reference numerals, and detailed explanation thereof will be omitted.

The entire slope 1a of the case 1 is formed of a transparent plate 1b such as a glass plate, and a direct reflection type photoelectric switch 2 is placed close to the lower back side of the transparent plate 1b. Furthermore, a heater 3a is provided inside the case 1 to melt the snow on the light-transmitting plate 1b, and a guide portion 9 is provided above the light-transmitting plate 1b so that the snow collects directly above the reflective photoelectric switch 2. It is something that

As described above, by making the slopes 1a all transparent plates 1b, the slopes 1a are formed on the same plane, so that the downstream flow of melting snow can constantly remove dirt from the transparent plates 1b, and malfunctions can be wiped out. .

[Effects of the invention] The present invention provides a transparent plate on the same plane as a part of the lower part of the slope of the case, and directs the light emitting part and the light receiving part to the transparent plate, and connects the direct reflection type photoelectric switch to the transparent plate. A heater is provided close to the back side of the light transmitting plate to melt the snow on the transparent plate, and a snow stopper is installed at the lower end of the slope, so that the light projecting part and the light receiving part are not exposed to the outside air, and the slope There are no irregularities around the transparent plate, so when the snowmelt water melted by the heater flows down the transparent plate, it can wash away the dirt that has adhered to the transparent plate, keeping the transparent plate clean at all times. can prevent malfunctions. Furthermore, by providing a snow stopper plate at the lower end of the slope, snow will not slide down the slope before being detected by the direct reflection photoelectric switch, and the snow will be reliably deposited on the transparent plate above the direct reflection photoelectric switch. Malfunctions can be reduced even when there is light snow.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the present invention, in which FIG. 1 is a perspective view, FIG. 2 is a sectional view, FIG. 3 is an explanatory diagram showing the operating state, and FIG. 4 is a control diagram. The electrical circuit diagram of the device, FIG. 5, is a perspective view of the second embodiment. DESCRIPTION OF SYMBOLS 1...Case, 1a...Slope, 1b...Transparent plate, 1c...Snow stopper plate, 2...Direct reflection type photoelectric switch, 2a...Light emitter, 2b...Light receiver, 3...
...heater board.

Claims (1)

[Scope of utility model registration request] A light transmitting plate is provided on the same plane as a part of the lower part of the slope of the case, and a direct reflection type photoelectric switch is placed close to the back side of the light transmitting plate with the light emitting part and the light receiving part facing the light transmitting plate. A heater is installed to melt the snow on the light board.
A snowfall detection device characterized in that a snow stopper plate is erected at the lower end of the slope.