JPH0615360Y2 - Photoelectric detector - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention is used for vehicle height detection at toll booths on expressways,
A photoelectric detector for outdoor use, which is a pair of a light emitter and a light receiver, in particular, when snow or icicles block the light beam emitted by the light emitter, or external light such as sunlight is applied to the light emitter or the light receiver. The present invention relates to a detection device that does not cause a malfunction due to incidence.

[Prior art]

Conventionally, when detecting the height of a vehicle at a toll booth on an expressway, the vehicle height detection device 1 shown in FIG. 3 is installed in an outdoor vehicle passage, and the detection device 1 has three units. Light emitter 2
And a light-emitting tower 6 having a column 5 fixed by a fixing mechanism 4 including the U-bolt 3, and three light-emitting towers each receiving a light beam 7 emitted from each of the three light-emitters 2. It is composed of a light receiver 8 and a light receiving tower 10 provided with a column 9 in which these light receivers 8 are fixed by a fixing mechanism 4, and further, all three beam lights 7 are substantially horizontal and as shown in the drawing. The main parts are configured so as to be arranged in the upper, middle, and lower three stages. Then, in this case, since the light receiver 8 is configured to output the electric signal 8a according to the amount of received light,
The vehicle height detection device 1 can detect the approximate height of the vehicle that blocks the light beam 7 by the signal 8a. Reference numeral 11 is a photoelectric detector including one light emitter 2 and a light receiver 8 corresponding to the light emitter 2. By the way, in the vehicle height detection device 1, the light emitter 2 and the light receiver 8 are configured as shown in FIGS. 4 and 5. That is, FIG. 4 is a side view of the light emitter 2 or the light receiver 8, and FIG. 5 is a view taken in the direction of arrow P in FIG. 4. In FIGS. 4 and 5, 12 is formed as a shed with a gable roof. The housing is fixed with a light emitting mechanism 13 for emitting the beam light 7 or a light receiving mechanism 14 for receiving the incident light beam 7 inside. Then, this housing 12 is the gable roof part.
The ridge 15a of 15 is formed so as to be parallel to the light beam 7,
In addition, one of the gable side housing side walls 16 is composed of a vertical portion 16a perpendicular to the ridge 15a and a bent portion 16c bent in a V shape with a ridge line 16b horizontal to the vertical portion 16a as a boundary. The bent portion 16c is provided with a rectangular through hole 17 that allows the light beam 7 to pass therethrough. 18 is a through hole
A transparent glass plate fixed in the casing 12 so as to close the cover 17, and a sheath heater 19 fixed in the casing 12 along the edge of the through hole 17 and facing the glass plate 18 with a gap. In this case, the casing side wall 20 facing the casing side wall 16 is fixed to the U bolt 3 as shown in the figure. Reference numeral 15b designates an eave-like projection of a gable roof portion 15 formed so as to further project from the housing side wall 16, and both 21 and 22 indicate a gable roof portion 15.
21a, 22 on the side wall of the casing 12 that is continuous with and opposite to each other.
Each of the side walls 21 and 22 formed so as to further project from the housing side wall 16 is a sleeve portion. in this case,
Gable roof part 15, protruding part 15b, side walls 21, 22 and sleeve parts 21a, 22a
Is formed by bending a single plate-shaped material, and in the case 12, the beam light 7 is horizontal, and the virtual plane including the beam light 7 and the ridge 15a is vertical, and 15a
Is positioned above the light beam 7 so that the fixing mechanism 4
It is fixed to the column 5 or 9. Reference numeral 23 is a triangular plate-like member fixed to the projecting portion 15b so as to abut the end of the eave-like projecting portion 15b in the roof portion 15 and project above the roof portion 15. In the photoelectric detection device 11, since the light projector 2 and the light receiver 8 are configured as described above, the snow accumulated on the roof portion 15 grows and hangs down in front of the eave-shaped protrusion 15b to block the light beam 7. The growth of the snow is prevented by the eave-shaped protrusions 15b so that the
5b and the sleeve-like portions 21a, 22a of the side walls 21, 22 prevent snow from adhering to the glass plate 18 due to snowstorms or the like. The sheath heater 19 described above has a function of removing snow and ice attached to the glass plate 18 or dew or the like attached to the glass plate 18 due to some cause even though the protrusion 15b and the sleeve-shaped portions 21a and 22a are provided. Extinguish,
And it is provided for the purpose of melting the snow on the roof part 15.

[Problems to be solved by the device]

Since the light projector 2 and the light receiver 8 are each configured as described above, they can be used outdoors, but according to the experience of the present inventors who applied them to vehicle height detection in a snowy area. Both the light projector 2 and the light receiver 8 have problems as described later. That is, in the projector 2 and the light receiver 8, the heater 19
Since the heater 19 is configured to continuously generate heat instead of being adjusted according to the temperature inside the housing 12, the temperature inside the housing 12 is controlled by the light emitting mechanism when there is no snow and no wind. 13
Further, the heat generation amount of the heater 19 is set so as to be equal to or lower than the maximum allowable temperature that does not adversely affect the light receiving mechanism 14. For this reason, when such a light projector 2 and a light receiver 8 are installed during snowfall at a wind speed of 2 [m / s] or more, for example, the amount of heat radiation irrelevant to snow melting may increase and the roof 15 may not be covered with snow. Further, due to such insufficient heat generation of the heater 19 and the fact that the heater 19 is not in contact with the glass plate 18, the snow and ice attached to the glass plate 18 may not disappear. Then, in the light projector 2 and the light receiver 8, the snow melted by the insufficient heat generation of the heater 19 is blinded to the front of the through hole 17 from the lower edge 23a of the plate member 23 which is substantially horizontal. From the upper edge 17a of the through hole 17 arranged substantially horizontally at the bent portion 16c of the housing side wall 16 in a laid down posture. In the same manner as described above, the light beam 7 may become icicles and hang down, and the light beam 7 may be blocked by these icicles. That is, in the photoelectric detection device 11 described above, since the heating by the heater 19 is insufficient, it is not possible to eliminate snow and ice attached to the glass plate 18, cloudiness, or the like, or because of icicles hanging in front of the through hole 17. In addition, there is a problem that the light beam 7 may be blocked and a malfunction may occur. Further, in the photoelectric detection device 11, the through hole 17 provided in the housing 12 is formed wider than the light emitting surface of the light emitting mechanism 13 and the light receiving surface of the light receiving mechanism 14, so that the light emitting mechanism 13 and the light receiving mechanism are formed.
Each 14 has a considerably wide field of view seen through the through hole 17. Therefore, in the light emitter 2 and the light receiver 8, there is a high probability that strong external light such as sunlight enters the light emitting mechanism 13 and the light receiving mechanism 14, and when such strong external light enters the light emitting mechanism 13, the light emitting function is reduced. Abnormality may occur and the light receiving mechanism
When such strong outside light enters the mechanism 14, the mechanism 14 cannot determine the presence or absence of the light beam 7. In the end, when strong outside light such as sunlight enters the light emitter 2 or the light receiver 8, photoelectric conversion is performed. The phenomenon that the detection device 11 malfunctions occurs. In other words, the photoelectric detection device 11 includes the light emitting mechanism 13 and the light receiving mechanism.
Since each of the 14 visual fields is wide, there is a problem that external light such as sunlight may be incident on these mechanisms to cause the detection device 11 to malfunction. An object of the present invention is to allow the housings of the light emitters and the light receivers to be sufficiently heated without adversely affecting the light emitting mechanism and the light receiving mechanism contained in these housings, and to transmit the light beam. To obtain a photoelectric detection device which can be used with high reliability even in a snowfall environment by preventing the window from becoming cloudy, snow and ice to adhere to the window, or icicles that block the beam light from occurring. It is in. Further, by narrowing the field of view of the light emitting mechanism or the light receiving mechanism, strong external light such as sunlight is prevented from entering these mechanisms as much as possible, and the malfunction of the photoelectric detection device due to such external light is reduced. Especially.

[Means for Solving the Problems]

In order to achieve the above object, according to the present invention, a light emitter and a light receiver that receives the beam light emitted from the light emitter and outputs an electric signal according to the received light amount are provided, and based on the electric signal. In the photoelectric detection device for detecting a pair of objects that block the light beam, the light emitter and the light receiver are both formed into a shed having a gable roof and one gable side wall is provided with an anti-fogging light. A housing provided with a transmission window, and one end fixed to the one gable side wall so as to surround the light transmission window, and the other end protruding from the gable side wall is cut off obliquely. A formed tubular hood, an electric heater fixed to the outer surface of the hood to heat the hood, and a temperature controller that detects the temperature of the inner wall of the housing and controls the energization current of the electric heater. And with The light emitting device further includes a light emitting mechanism for transmitting the beam light through the light transmitting window in parallel to the axis line of the hood, and the light receiving device further passes through the light transmitting window and the axis line of the hood. It is assumed that the photoelectric detection device is configured so that the light receiving mechanism for receiving the light beam incident in parallel with is provided inside the housing.

[Action]

With the above structure, the hood is heated by the electric heater according to the temperature of the inner wall of the housing regardless of the wind speed outside the housing because of the temperature controller, so the light emitting mechanism housed in the housing. The hood and the housing are heated strongly without adversely affecting the light receiving mechanism and the light receiving mechanism. Therefore, icicles that block the beam light do not occur, and the electric heater provides a strong heating effect and anti-fogging treatment. With the synergistic effect with the effect, there is no possibility that snow and ice or frost will adhere to the light transmission window or the window will be clouded by water droplets, and the beam light will not be blocked. A photoelectric detection device that can be used will be obtained. Also, with the above configuration, the field of view seen by the light emitting mechanism and the light receiving mechanism is limited by the hood, so the probability of strong external light such as sunlight entering these mechanisms is reduced, and Thus, it is possible to obtain a photoelectric detection device that is less likely to malfunction due to light.

【Example】

FIG. 1 is a block diagram of a light emitter 24 according to an embodiment of the present invention,
FIG. 2 is a block diagram of a vehicle height detection device 26 including a photoelectric detection device 25 using the light emitter 24 of FIG. 1, and FIG.
A side view corresponding to the drawing, FIG. 1 (B) is a view taken in the direction of arrow Q in FIG. 1 (A), and FIG. 1 (C) is R in FIG. 1 (A).
FIG. First, FIG. 1 will be described. That is, in FIG. 1, 27 is a housing corresponding to the housing 12 of FIG. 4, which is formed in the shape of a hut having a gable roof and provided with a light transmission window 28 on one gable side wall 27a. The light transmission window 28 is a circular through hole 28a provided in the side wall 27a, and an antifogging plate 28b fixed to the inner surface of the side wall 27a so as to hermetically close the through hole 28a.
It consists of and. Here, the anti-fog plate 28b is formed by forming, for example, a film of a water-absorbent resin called "Pelcoat" under the trade name on both surfaces of a plate-like pair of transparent glass or the like so that fogging does not occur. 29 is solidified by an unillustrated means on the outer surface of the housing side wall 27a so that one end surrounds the permeation window 28, and the other end 29a projected from the side wall 27a is formed into a shape obliquely cut off. A cylindrical hood, 30 is an electric heater fixed to the outer surface of the hood 29 so as to heat the hood 29, 31 is fixed in the housing 27, and the electric heater is detected by detecting the temperature of the inner wall of the housing 27. It is a temperature controller designed to control the energizing current of 30. In this case, the heater 30 is formed in a cylindrical shape so as to heat the outer surface of the hood 29 over the entire circumference.
It may be formed so as to heat a part of the outer side surface of the. Although not shown in the present embodiment, the outer periphery of the heater 10 is surrounded by a protective plate so that the heater 30 is not directly exposed to wind and rain. In FIG. 1, the above-mentioned light emitting mechanism 13 has a light transmitting window 28.
It is fixed inside the housing 27 so that the beam light 7 is emitted in parallel therewith and parallel to the axis of the hood 29. Then, the temperature controller 31 further causes the heater 30 so that the temperature of the inner wall of the housing 27 becomes a temperature between a predetermined upper limit value and a predetermined lower limit value.
The upper limit value is the maximum allowable temperature that does not adversely affect the equipment installed in the housing 27 including the light emitting mechanism 13 or the light receiving mechanism 14 described later,
Also, the lower limit is + for the hood 29 and the anti-fog plate 28b.
It is a temperature that does not fall below 1 ° C. In FIG. 1, 32 is a protective shelf for preventing small animals from entering the hood 29, and 33 is a housing side wall 2 facing the housing side wall 27a.
With a mounting seat fixed to the outer surface of 7b by means not shown,
When the nut 34 is tightened from the inside of the side wall 27b in a state in which the vertically mounted cylinder 5 is passed between the mounting seat 33 and the U-bolt 3, the mounting seat 33 is pressed against the cylinder 5, The light emitter 24 is fixed to the column 5 in a posture in which the light beam 7 is emitted from the hood 29 substantially horizontally. In this case, the housing 27 is illustrated with an upper portion 271 that is bent in a U shape and is composed of a gable roof-like portion 27b and both side walls 27e and 27f connected to the eave-like portion of the roof-like portion 27d. The side wall 27 is constructed so that it can be removed together with the upper part 271 from the housing 27 part by removing the fixing screw.
U bolt 3 inserted in a through hole (not shown) provided in b
The light emitter 24 can be fixed to the column 5 as described above by tightening the both legs with the nut 3 as described above. In FIG. 2, 35 is a light receiver fixed to the cylinder 9 so as to receive the light beam 7 emitted from the light emitter 24, and 25 is a light emitter.
24 and the above-mentioned light receiver 35 which receives the light beam 7 emitted by the light emitter 24 and outputs an electric signal 35a according to the amount of received light, and detects an object which blocks the light beam 7 based on the electric signal 35a. In the photoelectric detection device described above, the vehicle height detection device 26
Is composed of three sets of photoelectric detection devices 25 arranged in three stages of upper, middle, and lower as in FIG. Then, in this case, the light receiver 35 has the above-mentioned light receiving mechanism 14 in place of the light emitting mechanism 13 in FIG.
Therefore, in FIG. 2, the light receiver 35 is fixed to the column 9 as in the light emitter 24. In the photoelectric detection device 25, the light emitter 24 and the light receiver 25 are fixed to the cylinders 5 and 9, respectively, with the tip end face of the hood 29 held down so that snow and ice will not accumulate in the hood 29. ing. In the photoelectric detection device 25, the light emitter 24 and the light receiver 35 are respectively configured as described above, and therefore these light emitters
When the temperature of the atmosphere in which the 24 and the light receiver 35 are installed is low and the temperature of the hood 29 and the light transmission window 28 is less than + 1 ° C., the heater 30 is used to adjust the temperature regardless of the wind speed outside the housing 27. The hood 29 is heated strongly without adversely affecting the light emitting mechanism 13 and the light receiving mechanism 14, and the light transmission window 28 is indirectly heated through the hood 29 or the like so as to be + 1 ° C. or more. Therefore, in this case, icicles hang down from the tip of the hood 29, snow and ice adhere to the light transmitting window 28, or the light transmitting window 28 becomes cloudy due to water droplets, etc. It does not happen that the photoelectric detection device 25 malfunctions due to the disconnection of 7. Further, in the photoelectric detection device 25, the heating by the heater 30 may not be performed when the installation atmosphere of the device is + 1 ° C. or more, but even in such a case, the light transmission window 28
Since the anti-fog plate 28b that has been subjected to the above-mentioned surface treatment is provided in the photoelectric conversion device, the light transmission window 28 is fogged.
It does not happen that the 25 malfunctions. Therefore,
It can be said that the photoelectric detection device 25 is a photoelectric detection device that can be used with high reliability even in a snowfall environment. Further, in the light emitter 24 and the light receiver 35, the hood 29 is formed to be elongated so that the ratio L / D of the length L and the diameter D of the hood is, for example, 3 or more, and as a result, the light emitting mechanism.
The field of view of the housing 13 and the light receiving mechanism 14 looking out of the housing 27 through the hood 29 is very narrow and limited. Therefore, in this case, since strong external light such as sunlight is less likely to enter the light emitting mechanism 13 and the light receiving mechanism 14, the photoelectric detector 25 having the light emitter 24 and the light receiver 35 configured as described above, That is, the photoelectric detection device is less likely to malfunction due to external light. Although the hood 29 has a cylindrical shape in the above-described embodiment, the hood 29 is not limited to a cylindrical shape in the present invention, and is formed, for example, in a rectangular tube shape with the ridge line arranged above. It doesn't matter.

[Effect of device]

As described above, in the present invention, the light emitter and the light receiver that receives the light beam emitted by the light emitter and outputs the electric signal according to the received light amount are provided, and the light beam is generated based on the electric signal. In a photoelectric detection device for detecting an object to be blocked, both a light emitter and a light receiver are formed in a shed shape having a gable roof, and one gable side wall is provided with an anti-fog light transmission window. A body, and a tubular hood having one end fixed to the one gable side wall so as to surround the light transmission window and the other end projecting from the gable side wall cut off obliquely. An electric heater fixed to the outer surface of the hood so as to heat the hood; and a temperature controller that detects the temperature of the inner wall of the housing and controls the current flowing through the electric heater, and the light emitter further comprises Through the light transmission window The inside of the housing is equipped with a light emitting mechanism that emits a beam of light parallel to the axis of the hood.The light receiver further receives a light receiving mechanism that receives the light of a beam incident parallel to the axis of the hood through the light transmission window inside the housing. The photoelectric detection device was configured so as to be equipped with it. Therefore, with the above configuration, the hood is heated by the electric heater according to the temperature of the inner wall of the housing regardless of the wind speed outside the housing because of the temperature controller. The hood and housing are heated strongly without adversely affecting the light emitting mechanism and the light receiving mechanism.
For this reason, icicles that block the light beam do not occur, and snow and ice or frost adheres to the light transmitting window or the window is blocked by the synergistic effect of the powerful heating effect of the electric heater and the effect of anti-fog treatment. There is no possibility that the beam of light will be clouded and the beam of light will not be blocked. As a result, the present invention has an effect of providing a photoelectric detection device that can be used with high reliability even in a snowfall environment. Further, with the above configuration, the field of view seen by the light emitting mechanism and the light receiving mechanism is narrowed by the hood, so that the probability that strong external light such as sunlight is incident on these mechanisms is reduced. In addition, there is an effect that a photoelectric detection device that is less likely to malfunction due to such external light can be obtained.

[Brief description of drawings]

FIG. 1 shows the structure of a light emitter according to an embodiment of the present invention. FIG. 1 (A) is a side view, FIG. 1 (B) is a view taken in the direction of arrow Q in FIG. 1 (A), Figure 1 (C) is Figure 1 (A)
FIG. FIG. 2 is a block diagram of a vehicle height detection device composed of a photoelectric detection device using the light emitter shown in FIG. 1, and FIG. 3 is a block diagram of a vehicle height detection device composed of a conventional photoelectric detection device. FIG. 4 is a side view showing the configuration of the light emitting device or the light receiving device in the photoelectric detection device shown in FIG. 3, and FIG. 5 is a view taken in the direction of arrow P in FIG. 2,24 …… Light emitter, 7 …… Beam light, 8,35 …… Receiver, 8
a, 35a ... electric signal, 11,25 ... photoelectric detector, 12,27 ...
… Case, 13 …… Light emitting mechanism, 14 …… Light receiving mechanism, 15,27d ……
Gable roof, 16,27a …… side wall of chassis, 28 …… light transmission window,
29 …… Hood, 30 …… Electric heater, 31 …… Temperature controller.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Naoshi Noguchi 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Sanryo Heavy Industries Co., Ltd. Fuji Electric Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. An object comprising a light emitter and a light receiver for receiving a beam of light emitted by the light emitter and outputting an electric signal according to the amount of received light, the object being for blocking the light of the light based on the electric signal. In the photoelectric detection device for detecting, both the light emitter and the light receiver are formed into a shed having a gable roof, and a housing provided with a light transmission window subjected to anti-fog treatment on one gable side wall, A tubular hood having one end fixed to the one gable side wall so as to surround the light transmission window and the other end projecting from the gable side wall formed into an obliquely cut off shape, An electric heater fixed to the outer surface of the hood so as to heat the hood, and a temperature controller for detecting the temperature of the inner wall of the housing to control the energization current of the electric heater, and the light emitter. Is the light transmission window The housing is provided with a light emitting mechanism for transmitting the beam light in parallel therewith in parallel with the axis of the hood, and the light receiver further receives the beam of light incident in parallel with the axis of the hood through the light transmission window. A photoelectric detection device comprising a light receiving mechanism for receiving light inside the housing.