JP3056830B2 - Intruder detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable-like body stretched in a guard area, and an urging means for biasing the cable-like body in a tight state.
The present invention relates to an intruder detection device including: a detection unit that detects a movement of the cord-like body in order to detect a change in the tension state of the cord-like body.

[0002]

2. Description of the Related Art Such an intruder detecting device is provided, for example, if a rope is stretched along a fence provided around a guard area, and when an intruder who gets over the fence touches the rope. Since the tension changes, the intruder is not detected by detecting a change in the tension of the cord.

Conventionally, one end of a cord-like body is fixed to a column of a fence, and the other end is urged by an urging means under a predetermined tension. Then, the movement of the cord-like body at the pulled end is detected by the detecting means, and a detection signal is output when the movement amount reaches the set amount.

[0004]

One of the problems to be solved in the intruder detection device as described above is erroneous detection due to spontaneous expansion and contraction of the cord. That is, for example, the cord may expand or contract due to a difference in temperature between day and night, and the movement of the cord may be detected under the influence. In this case, it is necessary to ignore the movement amount exceeding the set amount and not to output the detection signal.

The present invention has been made in view of such circumstances, and an object thereof is to eliminate erroneous detection due to spontaneous expansion and contraction of a cord-like body.

[0006]

According to the present invention, there is provided an intruder detecting apparatus, comprising: a cord attached to a guard area; urging means for urging the cord in a tensioned state; It is one and a detection means for detecting a movement of the wick member to detect a change of state, the first feature structure, the wick member
Both ends are fixed , and a movable guide that guides the central portion of the cord-like body and that is movable in the direction of increasing and decreasing the tension of the cord-like body is provided. It is provided so as to bias in the direction of increasing the tension of the cord-like body,
The detection means is attached to the movable guide or a member that moves integrally with the movable guide.

The second characteristic configuration specifies a preferred specific configuration when the first characteristic configuration is implemented. The second characteristic configuration includes the movable guide and a pair of fixed guides located on both sides of the movable guide. The point is that the central portion of the shape is configured to be bent and guided in a bulging shape.

[0008]

According to the first feature, both ends are fixed.
Guides the central part of the cord, and increases or decreases the tension of the cord.
The movable guide is movable in the direction of increasing tension by the biasing means.
Is energized, wick member is biased tension increasing direction at its central portion, a detection means for and detect the movement of the wick member is attached to a member that moves integrally with it the <br/> movable guide member or I have. Therefore, the detecting means detects the movement at the center of the cord. In addition, the movement is detected only when a difference occurs in the tension from the center to the both ends of the cord.

In other words, for example, when the entire rope fixed at both ends is uniformly contracted due to a temperature difference or the like, the central part of the rope is pulled from both sides with the same tension.
As a result, the movable guide moves in the direction opposite to the biasing direction of the biasing means, but the detecting means also moves together with the movable guide, and the cable-like body is moved by the same amount on both sides with respect to the center. Income
The movement at the center of the cord is not detected because of contraction . On the other hand, if only one side is pulled from the center of the cord by, for example, an intruder, a difference occurs in the tension on both sides from the center of the cord, and the movement in the center of the cord is Will be detected. In addition,
If the body is evenly stretched due to temperature differences,
Since the cords extend by the same amount on both sides with respect to the center,
Similarly, movement at the center of the cord is not detected.

[0010] When the cord is stretched in a bent state at the center, the cord is guided only by the movable guide.
Although it can be urged to a stretched state, when the cord-like body is stretched substantially linearly, the above-mentioned action can be easily obtained by using a pair of fixed guides together as shown in the second characteristic configuration. be able to.

[0011]

As described above, according to the present invention, there is provided an intruder detecting apparatus in which erroneous detection is less likely to occur, excluding the influence of the case where the entire cord expands and contracts due to a temperature difference or the like. Reached.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 2, a cord-like body (hereinafter, referred to as a wire) 2 is stretched along a fence 1 provided around the guard area. Both ends 2 a and 2 b of the wire 2 are fixed to the fence 1, and the center portion is inserted through a tension detector 3 installed on the fence 1.

The wire 2 is passed through a sleeve 4 provided at a predetermined interval on the fence 1 so that a change in the tension of the wire 2 is transmitted to the tension detector 3 regardless of a force applied to any part of the wire 2. Is configured. Although FIG. 2 is drawn in a simplified manner, in practice, a large number of sleeves 4 are provided at intervals of about 2 m, and the distance from both ends 2 a and 2 b of the wire 2 to the tension detector 3 is about 50 m.

As shown in FIG. 1, the tension detector 3 is provided with a movable pulley 5 as a movable guide that guides the center of the wire 2 and is movable in the direction of increasing and decreasing the tension of the wire 2. . A fixed pulley 6 as a pair of fixed guides is provided on both sides thereof, and the pulleys 5 and 6 guide the central portion of the wire 2 in a bulging (U-shaped) shape.

The movable pulley 5 is pivotally attached to a movable frame 7 which is a member which moves integrally with the movable pulley 5, and a plate-like stem 7a of the movable frame 7 is provided.
Is movable vertically in the figure along a pair of columns 8 provided in the casing K, and is urged downward in the figure by a pair of coil springs 9 as urging means. Accordingly, the movable pulley 5 is movable in the tension increasing / decreasing direction of the wire 2 and is urged in the tension increasing direction of the wire 2.

The movable pulley 5 and the rotary shaft 5a are shared,
A rotary encoder 10 that generates a pulse in accordance with the rotation of the movable pulley 5 is attached to the movable frame 7 and constitutes a detection unit that detects movement (at the center) of the wire 2. The pulse signal from the rotary encoder 10 is
The signal is input to a separately provided detection circuit unit (not shown) through the cable 10a, and processing such as integration of the number of pulses is performed.

If a person trying to intrude beyond the fence 1 comes into contact with the P portion of the wire 2 and pulls it as shown by a broken line in FIG. 1, the wire 2 moves in the direction of the arrow and the movable pulley 5 moves upward in the figure and rotates in the direction of the arrow. Then, a pulse signal having a pulse number proportional to the rotation angle of the movable pulley 5, that is, the moving amount of the wire 2, is generated from the rotary encoder 10. Then, the number of pulses is integrated by the detection circuit unit, and when the integrated value reaches a predetermined value, a detection signal is output.

On the other hand, when the wire 2 contracts due to the influence of air temperature or the like, the entire pulley 5 contracts uniformly, so that the movable pulley 5 moves upward in the drawing but hardly rotates. Therefore, the rotary encoder 10 does not generate a pulse signal having the number of pulses enough to reach the predetermined value, and does not output a detection signal.

When the present apparatus is installed, the movable pulley 5 is positioned almost in the middle of the allowable movement range, and the tension of the wire 2 is adjusted to a predetermined tension (for example, 10 kg). Therefore, a detection signal is output not only when the wire 2 is pulled but also when it is loosened (cut). When the entire wire 2 expands, no detection signal is output in the same manner as described above.

Another embodiment will be described below. In the above embodiment, the rotation of the movable pulley 5 is increased or reduced by a gear mechanism or the like, and the rotary encoder 10 is rotated.
May be configured to rotate. Further, the detecting means is not limited to the rotary encoder, and a displacement sensor such as a differential transformer may be used.

As shown in FIG. 3 or FIG.
A reed switch 11b is mounted on the movable frame 7 so as to face the center of the magnet 11a, and the contact signal of the reed switch 11b is turned on or off when the wire moves by a predetermined amount. You may. In this case, the magnet 11a and the reed switch 1
1b corresponds to a detecting means for detecting the movement of the wire 2.

In FIG. 4, the movable frame 7 is pivotally attached at its center to the fixed frame of the tension detector 3 and is urged by a pair of coil springs 9 in the direction of increasing the tension of the wire 2. In this case, the fixed guide 6 in FIGS. 1 and 3 is unnecessary.

At a location where the fence is provided in an L-shape in plan view, a tension detector having the configuration shown in FIG. 1 is provided at a corner thereof to guide and bias a central portion of the wire stretched along the fence. In this case, the fixed guide body 6 may be omitted, and the wire may be guided and biased by only one movable guide body 5.

The movable guide 5 is not limited to a pulley, and a non-rotating guide made of a material having a small sliding friction coefficient may be used. The same applies to the fixed guide body 6.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is an internal structural diagram of a tension detector of an intruder detection device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an installation state of the intruder detection device.

FIG. 3 is an internal structural diagram of a tension detector according to another embodiment.

FIG. 4 is an internal structural diagram of a tension detector according to another embodiment.

[Explanation of symbols]

 2 cord-like body 5 movable guide body 6 fixed guide body 9 urging means 10 detection means

Claims (2)

(57) [Claims] 1. A cord-like body (2) stretched in a security area, and a biasing means (9) for biasing the cord-like body (2) to a tensioned state.
An intruder detection device comprising: a detection unit (10) for detecting a movement of the cord-like body (2) to detect a change in a tension state of the cord-like body (2) ; (2)
A movable guide body (5) is provided, the end of which is fixed , and which guides the central portion of the cord-like body (2) and is movable in the direction of increasing and decreasing the tension of the cord-like body (2). A biasing means (9) is provided so as to bias the movable guide body (5) in a direction of increasing the tension of the cord-like body (2) , and the detecting means (10) is provided with the movable guide body (5). Or an intruder detection device attached to a member (7) that moves integrally therewith. 2. A structure in which a central portion of the cord-like body (2) is bent and guided in a bulging manner by the movable guide body (5) and a pair of fixed guide bodies (6) located on both sides thereof. The intruder detection device according to claim 1, wherein