JPH0418079Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention can be used, for example, in vehicle passage detection devices, vehicle separation devices, etc. installed outdoors in cold regions. This invention relates to a device for preventing.

(Prior art) Vehicle passing detection devices that have already been put into practical use, including toll road systems, detect when a vehicle is passing by forming an optical path with light emitters and receivers facing both sides of the lane and blocking the optical path. The vehicle separation device is installed on an island at the entrance or exit of a lane on an expressway, facing each other on both sides of the lane, has a light emitter and receiver inside, and is connected to a treadle or axle treadle. In conjunction, it outputs dirt on the light receiver, vehicle code, and signals for forward and reverse vehicles. Both of these devices have in common that they are equipped with multiple light emitting and receiving sensors inside a housing that is installed upright outdoors, and the optical axis passage window of this light sensor is simply a It only has an opening, but if it is installed in an extremely cold region where the temperature is around -20°C, it is necessary to take measures to prevent snow from accumulating.

As shown in FIG. 6, the conventional snow accretion prevention device has cylindrical hoods 3 protruding from the casing 1 corresponding to a plurality of phototubes 2 arranged in a casing 1, respectively. A heater 4 is wrapped around the hood 3, and the lens of the phototube 2 (not shown) is attached.
The snow that adheres to the front surface is melted by the hood 3 heated by the heater 4 to prevent the optical axis from being blocked by the snow, and as shown in FIGS. 7 and 8, each phototube 2 is On the front side, there is a heater glass window in which an opening 5 large enough to allow all the optical axes of each phototube 2 to pass through is closed by a single piece of heater glass 6.

(Problems to be solved by the invention) However, in the one shown in FIG. 6, a heater 4 must be wrapped around each hood 3 corresponding to a plurality of phototubes 2, which complicates the configuration and increases cost. Not only that, but mud, snow, insects, and frogs thrown by the vehicle get inside the cylindrical hood 3, causing problems such as blocking the optical axis.

On the other hand, the structures shown in FIGS. 7 and 8 have a simpler structure than the structure shown in FIG. 6 and can be mass-produced, but as shown in FIG. There is a drawback that snow and ice S adheres to the glass mounting portion of the glass, and the optical axes of the uppermost and lower phototubes 2 are blocked by this snow and ice S. The cause of this is that the snow melted by the heater glass 6 adheres to the glass mounting part of the iron plate casing 1 around the heater glass 6, where the temperature is below 0°C, and becomes ice, and this icing phenomenon occurs repeatedly. This is because it becomes snow and ice.

Attach a large snow protection member to the front side of the housing,
We considered a device that blows hot air onto the optical axis of a phototube, but the area within 250 m/m from the edge of the island where this type of road-related equipment is installed is an area where there is a possibility of collisions with passing vehicles. However, it is a practical problem to install a large device in front of the housing.

(Purpose of the invention) The present invention was devised in view of these problems.
Another object of the present invention is to provide a device for preventing snow and icing on a heater glass window, which can reliably prevent snow from accumulating on the heater glass and icing on the surrounding area without using large members or devices.

(Means for Solving the Problems) In order to achieve the above object, the device for preventing snow accumulation and icing on heater glass windows of the present invention includes a light emitting and receiving sensor disposed inside the housing, and a light emitting and receiving sensor. In a vehicle passage detection device, a vehicle separation device, etc., in which a heater glass is arranged in front of the light emitting/receiving sensor and light is emitted/received to the light emitting/receiving sensor via the heater glass, the heater glass is located in front of the heater glass. A hood having a rectangular frame shape that surrounds the heater glass and has a protruding frame portion extending forward from the housing front plate is interposed between the hood and the opening of the housing front plate. A heater is interposed between the front side and the peripheral edge of the opening of the housing via a heat insulating material.

(Function) With the above configuration, even when installed in an extremely cold region with severe weather conditions, the protruding frame of the hood prevents snowfall and large amounts of snow adhering to the casing from entering the front side of the heater glass. A hood that prevents heat conduction by an insulating material to the glass mounting part of the casing, which prevents the temperature from heating to below 0℃,
To prevent snow heated intensively by a heater and melted by a heater glass from adhering to a glass mounting part and turning into ice. Therefore, snow and ice will not accumulate inside the hood.

(Example) Hereinafter, an example of the present invention will be explained in detail based on the drawings.

1 to 4 show an embodiment of the present invention,
In these figures, similar to those in FIGS. 7 and 8, a light emitting/receiving sensor (phototube 2...
) is arranged, and the light emitting/receiving sensor (phototube 2...) is arranged.
) is provided with a heater glass 6 in front of the light emitting/receiving surface.
Light is emitted and received through the heater glass 6 to the light emitting/receiving sensor (phototube 2 . . . ).

7 is a cross section L formed into a rectangular frame shape from aluminum.
The mounting frame part 7a and this mounting frame part 7 are
and a protruding frame portion 7b extending in the orthogonal direction from a. The protruding frame portion 7b extends from the inside of the casing 1 to the casing 1.
It is formed in a size that can be inserted into the opening 5 of the front plate 1a of the housing 1, and is attached in a state extending beyond the front plate 1a of the housing 1, as shown in the figure. 8
is a hood heater consisting of a laminate heater with a heat insulating material 9 attached to the front surface, and the protruding frame portion 7 of the hood 7
The hood 7 and the front plate 1 of the housing 1 are fitted onto the outer periphery of b.
It is interposed between the inner surface of a. As shown in FIG. 4, the hood heater 8 and the mounting frame 7a of the hood 7 are attached to a glass presser fitting 11 with a spacer 10 interposed between the front plate 1a and the mounting frame 7a of the hood 7. Therefore, it is attached together with the heater glass 6 to the inner surface of the front plate 1a with screws 12.
In addition, 13 is a glass packing.

Therefore, a large amount of snow that adheres to and accumulates on the front plate 1a of the housing 1 is prevented from going around to the heater glass 6 side by the protruding frame portion 7b of the hood 7, and is melted by the heater glass 6. The snow is
The hood 7, which is heated by the heater 8, flows down without turning into ice. Therefore, snow and ice do not adhere to the periphery of the heater glass 6 unlike in the conventional case. Further, since the hood 7 is separated from the cold front plate 1a by the heat insulating material 9 and is intensively kept warm by the hood heater 8, the heater 8 can sufficiently achieve its intended purpose with a heater capacity within the limit.

Incidentally, the hood 7 is not limited to the one in the above embodiment.
For example, if the inner flange frame portion 7c is provided as shown in FIG. 5, icing on the peripheral portion of the heater glass 6 can be more reliably prevented. Furthermore, in the above embodiments, the case where the application is applied to road-related equipment such as a vehicle passage detection device was explained, but the device is installed outdoors in an extremely cold region, and the visibility is limited, such as for transmitting the optical axis of an optical sensor. It goes without saying that the present invention can be applied to various types of heater glass windows in which important factors are considered.

(Effect of the invention) As explained above, according to the device for preventing snow and icing on the heater glass window of the present invention, there is a Since the hood is interposed in a rectangular frame shape that surrounds the heater glass and has a protruding frame portion that extends forward beyond the front panel of the casing, a large amount of snow that adheres to the front panel of the casing is removed from the protruding frame of the hood. It is possible to effectively prevent it from going around to the heater glass side.

Moreover, in the case of the present invention, the rectangular frame-shaped hood is
Since the cold housing is insulated by the insulation material and heated in a concentrated manner, it is possible to perform effective heating without losing heat from the heater due to ice formation on the housing, making it possible to heat the cold housing efficiently. Snow and ice accretion around the heater glass can be reliably prevented by using a small-capacity heater. Further, since the projecting frame portion of the hood only needs to be slightly projected from the front panel of the housing, there is no problem in terms of size and appearance when applied to road-related equipment.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the device for preventing snow and icing on heater glass windows according to the present invention, in which FIG. 1 is a perspective view, FIG. 2 is a longitudinal sectional view, and FIG. 3 is a cutting plane. 4 is an exploded perspective view, FIG. 5 is a cutaway plan view of another embodiment of the present invention, FIG. 6 is a perspective view of a conventional device, and FIGS. 7 and 8 are respective views of other conventional devices. FIG. 2 is a perspective view and a longitudinal cross-sectional view. DESCRIPTION OF SYMBOLS 1... Housing, 1a... Front plate of the housing, 2... Phototube 2 (light emitting/receiving sensor), 5... Opening in the front plate of the housing, 6... Heater glass, 7... Hood,
7b...Protruding frame portion, 8...Heater.

Claims (1)

[Scope of Claim for Utility Model Registration] A light emitting/receiving sensor is disposed within the housing, a heater glass is disposed in front of the light emitting/receiving sensor, and light is emitted and received to the light emitting/receiving sensor via the heater glass. In a vehicle passage detection device, a vehicle separation device, etc., a rectangular frame-shaped frame surrounding the heater glass is provided between the heater glass and an opening of a front panel of the housing located on the front side of the heater glass. A hood having a protruding frame extending forward from the front plate is interposed, and a heater is interposed between the hood and the peripheral edge of the housing opening via a heat insulating material on the front side. A device for preventing snow and icing on heater glass windows.