JPH056338U - Infrared transmitter / receiver - Google Patents

Abstract

(57) [Summary] [Purpose] This is an infrared transmitter / receiver device that ensures reliable operation even under conditions where frost is attached to the device body by radiative cooling. Rainwater enters the device body even in rainy weather. It was hard to do. [Structure] An optical element (6) which is arranged in the casing (A) and transmits or receives infrared rays, and an infrared beam which is arranged in front of the casing (A) and which is transmitted and received by the optical element (6). In an infrared transmitting / receiving device provided with a translucent plate positioned in the passage, a recess is formed on the outer surface of the translucent plate and the recess is positioned within the infrared beam transmitting region, and the upper wall of the recess is further provided. A ventilation hole (23) for communicating the inside and outside of the casing (A) was provided in the above.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an infrared transmitter / receiver, and more particularly to an infrared transmitter / receiver capable of ensuring reliable operation even under conditions where frost is attached to the main body by radiation cooling. It was made difficult to penetrate.

[0002]

[Prior art and problems]

 Infrared ray transmitting / receiving devices are widely used in crime prevention alarm devices and the like, and an alarm is activated when infrared rays traveling between devices arranged opposite to each other are blocked by an intruder or the like. An example of this type of infrared transmitting / receiving device is disclosed in Japanese Patent Publication No. 2-3234.

As shown in FIG. 7, a light emitting element or a light receiving element (hereinafter referred to as an optical element) and a light collecting mirror (4) are housed in a casing (A), and at the front of the casing (A). The translucent plate (2) provided is made of a material that transmits infrared rays, and a small opening window (5) is cut into the translucent plate (2). The opening window (5) exists in the region through which the infrared beam passes, and its area is set to be about 1/100 or more of the sectional area of the infrared beam.

The reason why the area of the opening window (5) is set to the above size is as follows. That is, the infrared security device has a sensitivity margin so that it can operate normally even under the worst weather conditions such as rain, fog, snow, etc. This value is generally the minimum required for fine weather and dry weather. Since the amount of light is 50 to 100 times the amount of light, the area of the opening window (5) capable of ensuring a complete amount of light transmission is set to about 1/100 or more of the cross-sectional area of the infrared beam.

The above-mentioned conventional device has the following advantages because the opening window (5) is formed. Infrared rays are emitted from the surface of the earth (2) when night frost adheres to the transparent plate (2) due to meteorological radiation cooling in which infrared rays are emitted toward the sky from the earth's surface. The transmittance will be extremely reduced. However, in the case of the above, there is an opening window (5) with a size of 1/100 or more of the cross-sectional area of the beam in the transmission region of the infrared beam, so it is necessary for the detection operation of the optical element (6). The amount of infrared rays (1 or more per 100 minutes of the total amount of light) is received by the optical element (6), and the optical element (6) reliably outputs a detection signal.

However, in the above-mentioned conventional one, since the opening window (5) is simply perforated on the surface of the translucent plate (2), the casing ((5) is opened through the opening window (5). A) There was a problem that rainwater could easily enter the area. The present invention has been made in view of the above points, and it is provided with "an optical element (6) arranged in the casing (A) and transmitting or receiving infrared rays, and a front surface of the casing (A). Infrared transmitter / receiver equipped with a translucent plate positioned in the path of the infrared beam transmitted and received by the optical element (6) '', the optical element ( The task is to prevent rainwater and the like from entering the casing (A) while ensuring the reliable detection operation of 6).

[0007]

[Technical means]

 The technical means of the present invention for solving the above-mentioned problem is to form a concave portion on the outer surface of a light-transmitting plate and locate the concave portion in the infrared beam transmitting region, and further to form a casing ( The ventilation hole (23) that communicates the inside and outside of A) is provided ”.

[0008]

[Action]

 The above technical means act as follows. Since the concave portion is formed on the surface of the translucent plate, the amount of infrared radiation emitted from the internal space of the concave portion to the sky is suppressed to be small, and radiative cooling is less likely to occur. Further, since the air is stagnant in the recess and the heat retained in the air keeps the interior of the recess warm, it is difficult to cool the interior of the recess.

As a result, nighttime frost is less likely to adhere to the inner wall of the recess, and there is less concern that the amount of infrared rays passing through the part will decrease. That is, according to the above technical means, it is possible to suppress a decrease in the amount of transmission of all the infrared rays when frost adheres to the surface of the transparent plate. Further, since the ventilation hole (23) is formed on the upper wall of the recess, the temperature difference between the inside and the outside of the casing (A) can be reduced.

[0010]

【effect】

 The present invention has the following unique effects. Even if frost adheres to the surface of the translucent plate due to radiative cooling and the infrared transmittance decreases, the decrease in the total infrared ray transmission can be suppressed by forming the concave portion, thus ensuring the optical element (6) In addition to ensuring the above-mentioned detection operation, there is no concern that rainwater or the like will enter the casing (A) because an opening window is not formed on the front surface of the translucent plate as in the conventional case.

Furthermore, since a ventilation hole (23) can be formed in the upper wall of the recess to reduce the temperature difference between the inside and outside of the casing (A), dew condensation on the inner surface of the casing (A) can be suppressed. From this point as well, the infrared ray transmittance does not decrease, and a reliable detection operation can be secured.

[0012]

【Example】

 Next, the embodiments of the present invention described above will be described in detail with reference to the drawings. As shown in FIG. 1, the device body (1) is fixed to the back plate (7) which is combined with the translucent cover (2) to form the casing (A) with screws (10) and (10). The device body (1) is composed of a pair of upper and lower optical devices (11) and (11) and a support body (12) supporting the optical devices. Further, the translucent cover (2) which functions as a translucent plate is provided with recesses (21) and (21) which are located in the path of infrared rays incident on the optical device (11). The formation of the recesses (21) (21) suppresses radiative cooling in the recesses (21) at night and the like, and suppresses adhesion of frost and the like to the parts. As a result, the amount of infrared light sent to the optical device (11) side does not decrease as much as frost does not adhere to the inner wall of the recess (21), and the minimum amount of infrared light required for the detection operation of the optical element (6) Can be transmitted.

Further, ventilation holes (23) and (23) are formed in the upper wall of the recesses (21) and (21), and the ventilation holes (23) prevent the temperature difference between the inside and outside of the casing (A). The amount is reduced to prevent dew condensation on the inner surface of the casing (A). Since the ventilation holes (23) and (23) are formed on the upper walls of the recesses (21) and (21), this is the same as the conventional one in which the opening window is simply formed on the front surface of the through hole cover (2). There is no fear that rainwater will enter the casing (A).

The structure of the device body (1) will be described in more detail. Each optical device (11) has a box body (15) having a concave rear wall and functioning as a condenser mirror (14). The box body (15) is formed of a lid body (16) that covers the front open part and is made of a material that transmits infrared rays, and the lid body (16) is mounted on the mounting substrate (17). A light emitting element and a light receiving element as an optical element (6) fixed to the are arranged. Two optical elements (6) are arranged on the mounting substrate (17), and a total of four optical elements (6) are provided in the upper and lower optical devices (11) (11). In addition, as shown in FIGS. 2 and 4, aiming windows (41) and (41) are formed on the front surface of the lid body (16), and near the left and right ends of the front surface of the lid body (16). The viewing window (42) (42) is perforated. A posture adjusting mirror (43) is arranged at an intersection of a straight line connecting one sighting window (41) and one sighting window (42) located farther from the sighting window (41).

A pair of support shafts (18) and (18) project from the left and right side surfaces of the optical device (11), and the support shafts (18) and (18) stand upright from inside the support body (12). It is swingably supported by the support arms (25) and (25) of. Further, a kick spring (26) is interposed between the support arm (25) and one (upper) optical device (11), which applies a rotational force to the optical device (11). ing. Further, one supporting arm (25) for supporting the upper optical device (11) is provided with a bending piece (27) which bends inward as shown in FIGS. ) Has an angle adjusting screw (28) screwed into it, and the tip of the angle adjusting screw (28) has a protruding wall (29) protruding from the side wall of the box (15). ) It pushes backwards against the urging force of.

The optical device (11) located above and the optical device (11) located below are connected via a rotating plate (30) rotatably supported by a shaft (31), The rotating plate (30) is formed with a pair of notches (32) (32) that open in the radial direction. And, in the notches (32) (32), pins (34) (34) provided on arms (33) (33) integrally protruding from the outer peripheral wall of each optical device (11) (11) are provided. It has been inserted. Further, as shown in FIG. 6, the support arm (25) for supporting the optical device (11) as a whole is fitted and fixed to the end of the inner cylinder (19) inserted in the cylindrical support (12). It projects upright from the disc (20), and a square hole (55) is cut in the center of the disc (20). Then, the above-mentioned arm (33) (protruding from the box body (15)) is engaged with the notch (32) of the rotating plate (30) through the square hole (55).

An intermediate cylinder (13) is interposed between the inner cylinder (19) and the support body (12), and the intermediate cylinder (13) and the support body (12) are not shown. It is connected through the mechanism. Further, as shown in FIGS. 1 and 3, a rotary knob (35) rotatably supported by a screw (36) is arranged at the upper end of the intermediate cylinder (13). The engaging projection (37) protruding downward from the vicinity of the outer periphery of (35) engages with the notch (38) on the outer periphery of the disc (20) holding the optical device (11) as shown in FIG. There is.

In this device, as shown in FIG. 5, one side of the passage (C) is a device body (1) incorporating a light emitting element, and the other side is a device body (1) incorporating a light receiving element. ) Are arranged so that they face each other, and four infrared beams travel between them. As shown in FIG. 1, the device body (1) is properly fixed to the column (D), and the screws (46) (46) are removed to remove the translucent cover (2).

Next, when the optical device (11) is rotated in the horizontal direction, the optical device (11) is fixed to the disc (20) and the inner cylinder fixing the disc (20). It rotates with respect to the support body (12) integrally with (19) and the intermediate cylinder (13). At this time, the support body (12) and the intermediate cylinder (13) inside the support body (12) are discontinuously rotated by a constant angle by a ratchet mechanism (not shown). As a result, the optical devices (11) of the device body (1) that face each other across the passage (C) are in a state where they are substantially facing each other. In this state, look through the sighting windows (42) (42) shown in FIG. 4 and the sighting window (41) through the posture adjusting mirror (43). Then, the horizontal and vertical direction of the optical device (11) can be seen so that the sighting window (41) formed in the optical device (11) of the other device body (1) facing through the passage (C) can be seen. Fine-tune the directional posture.

That is, by rotating the rotary knob (35) shown in FIG. 3 and engaging the engaging projection (37) protruding from the rotary knob (35) with the notch (38), the disc (20) is Rotate slightly to finely adjust the horizontal angle. When the screwing amount of the angle adjusting screw (28) is adjusted, the screwing force and the biasing force of the kick spring (26) cause the optical device (11) to swing around the support shaft (18) in the vertical plane. To do. Then, the arm (33) protruding to the lower surface of the box body (15) constituting the optical device (11) rotates the rotating plate (30) and engages with the lower end of the rotating plate (30). The other optical device (11) swings. Accordingly, when the vertical angle adjustment of the upper optical device (11) is performed, the angle adjustment of the lower optical device (11) is automatically performed.

In this way, by adjusting the arrangement posture of the optical device (11) in the horizontal direction and the vertical direction, both optical devices (11) facing each other with the passage (C) in between are accurately opposed. Finally, the translucent cover (2) is covered with the screws (46) (46). When the device body (1) is operated in this state, the infrared light emitted from the optical element (6) of the one device body (1) causes the transparent cover (2) and the lid inside the transparent cover to be exposed as shown in FIG. The light passes through the body (16), is reflected by the condenser mirror (14), is collected by the optical element (6), and is received by that portion. In this case, part of the infrared beam (V) passes through the recesses (21) (21) of the translucent cover (2), but the interior of the recesses (21) (21) at night is as described above. Since it is difficult to receive radiant cooling, frost or the like is less likely to adhere to the inner wall or the like of the recess (21). Therefore, the amount of frost adhering to the surface of the translucent cover (2) due to the radiation cooling is reduced as a whole, and the reliable detection operation of the optical element (6) can be secured. The area of the openings of the recesses (21) (21) is set to be at least (1/100) or more of the cross-sectional area of the infrared beam (V), which allows the surface of the casing (A) to be protected from frost. Even if such substances adhere to the optical element (61), a detectable amount of the infrared ray beam (V) reaches the optical element (6).

Further, ventilation holes (23) and (23) are formed on the upper walls of the recesses (21) and (21) to reduce the temperature difference between the inside and the outside of the device body (1). Even if the outside air temperature drops, the risk of condensation on the inner surface of the casing (A) is reduced, and unlike the conventional ones, the through holes that are exposed at the front surface of the casing (A) are not formed. There is no concern that the etc. will enter the casing (A).

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention.

[Fig. 2] Front view of the casing (A) removed

FIG. 3 is a plan view of the device body (1)

FIG. 4 is a cross-sectional view of a portion of the optical device (11) that passes through the sighting windows (41) and (41).

FIG. 5 is a perspective view showing an arrangement state of the apparatus main body (1) (1)

FIG. 6 is an exploded perspective view of an essential part of the embodiment of the present invention.

FIG. 7 is an explanatory diagram of a conventional example.

[Explanation of sign]

 (1) ・ ・ ・ Device body (2) ・ ・ ・ Transparent plate (6) ・ ・ ・ Optical element (21) ・ ・ ・ Concave (A) ・ ・ ・ Casing

Claims (1)

[Claims for utility model registration] [Claim 1] An optical element (6) arranged in the casing (A) for transmitting or receiving infrared rays, and the casing.
In an infrared transmitting / receiving device provided on the front surface of (A) and having a translucent plate positioned in the path of an infrared beam transmitted / received by an optical element (6), a recess is formed on the outer surface of the translucent plate. At the same time, the infrared transmitting / receiving device is provided in which the recess is located in the infrared beam transmitting region, and the upper wall of the recess is provided with a ventilation hole (23) for communicating the inside and outside of the casing (A).