JP3345578B2 - Displacement detection sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement detection sensor of an intruder monitoring sensor for detecting a tension displacement of a wire used for a general access control and an intrusion sensor from a facility section such as a fence.

[0002]

2. Description of the Related Art In general ranches, aviation, factories, and other facilities,
Fences are installed to prevent outsiders from entering important facilities without permission. Whether an outsider has entered the important facility without permission is determined by an intruder detection sensor. As the intruder detection sensor, infrared, vibration, tension load, microwave, image processing, and the like are used.

[0003] Among these sensors, infrared sensors are suitable for places such as traffic gates where people and vehicles enter and exit. It is said that a tension type sensor that detects an intermediate pole between fixed poles in a facility such as a fence or a block wall is suitable. The latter will be further described.

[0004] Assuming a general-purpose tension sensor, a contact unit is provided in the middle of one wire. The contact unit always closes the contacts, and when tension is applied to the wire, the contacts are opened and an electric signal is displayed on the central control panel installed in the guard room, etc. Think of it as a way to know that you are invading.

[0005]

However, in the tension sensor, when tension is applied to the wire, the wire tension level at which the contact is opened is small, and the contact is immediately opened by a small animal such as a bird. There is fear. For example, 5 kg to 1 kg or less of gulls, crows, starlings, etc. described in FIG.
When a bird such as a swallow stops or comes into contact with the wire, the contact is immediately opened, and there is a drawback that a false alarm may be issued and a false intruder may be issued. Also, it has been desired to realize a displacement detection sensor that can be easily applied to existing tension type sensors. As a tension sensor, Japanese Patent Application Laid-Open No.
No. 19192 can be mentioned.

An object of the present invention is to provide a displacement detection sensor that can reliably detect a bird and an intruder and can be easily applied to an existing tension type sensor.

[0007]

According to a first aspect of the present invention, there is provided a displacement detecting sensor having a support plate disposed at one end of a main body of a detection sensor, and a support plate extending through one side of the support plate. The extending tension wire, a movable lever that rotates according to the movement of the tension wire fixed to the support plate extends into the detection sensor main body, and the movable lever rotatably inserted into the main shaft penetrating the detection sensor main body connects the main shaft. Two switches that turn in the moving direction of the tension wire as a fulcrum and turn on and off the current by the pressing force of the movable lever in the turning direction of the movable lever are fixed to the detection sensor main body, and the current from the tension wire is An object of the present invention is to provide insulating means for preventing the detection sensor from flowing through the support plate.

In the displacement detecting sensor according to the second aspect of the present invention, two switches for turning on and off the current by the pressing force of the movable lever in the rotating direction of the movable lever are fixed to through holes provided in the detection sensor main body.

In the displacement detection sensor according to the third aspect, when tension is applied to the tension wire between the detection sensor main body and the support plate, energy is accumulated by a force of the support plate pressing the detection sensor main body, When the tension of the tension wire is lost, the force of the support plate pressing the detection sensor body is lost, and an elastic member is provided to return the movable lever to the original position by the pressing force releasing the accumulated energy.

According to a fourth aspect of the present invention, a tension wire extending through one side of a support plate disposed at both ends of the detection sensor main body, and a movable lever which rotates in accordance with the movement of the tension wire fixed to each support plate are detected. Two movable levers extending into the sensor body and rotatably inserted into a main shaft penetrating through the detection sensor body rotate in the direction of movement of the tension wire with the main shaft as a fulcrum, and are movable in the direction of rotation of each movable lever. 4. An insulating means for fixing four switches for turning on and off the current by the pressing force of the lever to the detection sensor main body and preventing the current from the tension wire from flowing to the detection sensor main body via the support plate. To claim 3.

According to a fifth aspect of the present invention, there is provided any one of the first to fourth aspects, wherein the support plate is formed of an insulating member.

According to a sixth aspect of the present invention, there is provided any one of the first to fourth aspects, wherein a tension wire portion corresponding to the support plate is covered with an insulating member.

According to a seventh aspect of the present invention, the movable lever and each switch are arranged on the detection sensor main body such that the direction of movement of the tension wire and the direction of operation of the movable portion of the movable lever and each switch are in the same direction. The method according to any one of claims 1 to 6, wherein

Further, the tension wire is supported by a plurality of poles, and a displacement detection sensor provided between the tension wires is provided as one unit tension wire, and a plurality of units of the one unit tension wire are provided as poles. 8. The arrangement according to claim 1, wherein the support is arranged in a width direction orthogonal to the support direction. 9.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Each figure shows a part of a fence stretched around an important facility. That is, five poles 2A, 2B, 2C, 2D are provided in a part of the facility wall 1.
And the center pole 2E is buried at a predetermined interval, and the terminal and middle poles 2A, 2B and 2C, 2D are supported on the ground. End guide rollers 3A, 3B and intermediate guide rollers 3C, 3D are mounted above and below the end and intermediate poles 2A to 2D. The end guide rollers 3A and 3B are impellers that rotate when the tension wire 4 moves. The intermediate guide rollers 3C and 3D, for example, the intermediate guide roller 3C are formed in a curved shape so that the tension wire 4 is easily bent as shown in FIGS.

A tension wire 4 for moving the end guide rollers 3A and 3B passes through a stopper 5 and is connected to a spring 6. The stopper 5 is attached to the terminal poles 2A and 2B. The other wire 4A connected to the spring 6 is fixed to an operation handle 7 shown in FIGS. 3 (C) and 3 (D). The operation handle 7 is fixed to a support plate 8. The support plate 8 is attached to the end poles 2A and 2B. The operation handle 7 is provided on the end pole 2A side.

The stopper 5 includes an insulating plate 5A, a spring 6, and an insulating guide 5B, and is incorporated in the spring position detecting cover 9. Therefore, the tension wire 4 and the spring 6 are connected in the spring position detecting cover 9 via the insulating guide 5B. The spring 6 is surrounded by a spring position detection cover 9. The spring 6 in the spring position detecting cover 9 is connected to the other wire 4A again and fixed to the operation handle 7.
A change in the spring 6 can be immediately recognized by looking at the protrusion dimension between the upper side of the spring position detection cover 9 and the stopper 5, that is, 5Y.

The operation handle 7 comprises a square portion 11A and handle insertion portions 11B at both ends.
If the operation handle 7 is inserted into 1B or the fixed operation handle is rotated, the other side wire 4A is wound around the square portion 11A in accordance with the rotation, and tension is applied to each wire to become the tension wire 4. If the other wire 4A is wound around the square portion 11A, the other wire 4A can be wound without slipping, so that there is an advantage that the winding operation can be made more efficient. Also, an insulating plate 5 is provided in the spring position detecting cover 9.
The wire 4 is insulated by A and the insulating guide 5B.
These are shown as insulating tight 12 in FIG.
The tension wire 4 constituted a loop circuit by the insulating tight 12. When a sufficient tension can be obtained in the loop circuit, the insulating tight 12 is not required.

The position of two tension wires will be described with reference to FIG. FIG. 2 (A) is a plan view of the end wall 2A and 2B, the intermediate poles 2C and 2D, and the center pole 2E in the facility wall 1.
And the wires 4 are stretched in two lines. Since here the resistance value R ₁ to R ₄ of the wire 4 are based fixed point center pole 2E, shown as a resistance value of Article 4 of the wire with the horizontal direction of the end poles 2A and 2B.

FIGS. 2 (B) to 2 (D) are side views of the facility wall 1. FIG. 2 (B) shows that when the terminal pole 2A is bent to about 35 degrees at the front end, the terminal guide roller 3A becomes perpendicular to the wire 4. Is pulled by the stopper 5 and fixed to the operation handle 7. Therefore, even when the number of the wires 4 is two, the distance to the operation handle 7 is large, so that they can be seen in the front view like the terminal pole 2A in FIG.

FIG. 2C shows the case of the intermediate pole 2C, and FIG. 2D shows the case of the center pole 2E. The wires 4 are fixed to both ends of the displacement detection sensor 15.

The tension of the tension wire 4 is detected by a displacement detection sensor 15 attached to the center pole 2E. The upper and lower tension wires 4 are connected to a displacement detection sensor 15.
, And the resistance of each detection area is defined as R ₁ , R ₂ , R ₃ , and R ₄ . Although details will be described later, FIG.
(A), the gravity W to the tension wire tension wire 4, for example R ₂ of each detection region as (B) acts, tension wires 4 are moved or rotated in the clockwise direction, the displacement detecting sensor 15 movable lever for example, by first moving the lever 18A is a rotation in the same direction as a fulcrum spindle 17, for detecting the tension generating an electric signal to close the switch S _3. Details of the detection will be described later, and a detailed structure of the displacement detection sensor 15 will be described with reference to FIGS.

FIG. 5A is a plan view of the displacement detection sensor 15 as viewed from the top, and FIG. 5B is a vertical side view taken along the line VV of this plan view. FIG. 6B is a diagram illustrating the vi-vi of FIG.
FIG. 6A is a vertical side view of the line, and FIG.
It is p sectional drawing.

A main shaft 17 is inserted into a through hole formed in the center of a detection sensor main body 16 having a square appearance. The first movable lever 18 </ b> A and the second movable lever 18 </ b> B are inserted into the main shaft 17, and a screw formed at the tip of the fixed portion 17 </ b> B of the main shaft 17 is screwed into, for example, a screw of a nut 17 </ b> C. It is fixed to.
The first movable lever 18A and the second movable lever 18B extend in the directions of the upper and lower tension wires 4. The first movable lever 18A and the second movable lever 18B rotate around the main shaft 17 in the tensioning direction of the tension wire 4. For example, when the upper tension wire 4 is pulled a to the right, the first movable lever 18A rotates by angle a. Four switches S ₁ ,
S ₂ , S ₃ , S ₄ For example, a micro switch is arranged in the detection sensor main body 16.

The first and second switches S ₁ and S ₂ are arranged in arrangement holes 19 A formed on both side surfaces on the upper end side of the detection sensor main body 16, and the mounting plate 20 attached to each switch is arranged in the arrangement hole 19.
A is fixed to the step of A by a screw or the like. Mounting plate 20
In addition, a hole 19B through which a wiring is drawn in and out of the switch is formed in the detection lid 16B that closes the arrangement hole 19A. Detection lid 1
When the switch 6B is removed, each switch can be pulled out, and the spring pressure of the movable spring SB, which is the movable portion of the switch, can be adjusted. The first switch S ₁ and the second switch S ₂ is associated arranged in the arrangement hole 19A and the direction opposite to each other. The third switch S ₃ and the fourth switch S ₄ are arranged in the arrangement holes 19A formed on both side surfaces on the upper end side of the detection sensor main body 16 and have exactly the same configuration except that the arrangement positions are different from those of the first and second switches. Detailed description is omitted. Each switch has a contact SA as shown in FIG. 8, for example.

A detection spring 22 is disposed between the upper and lower ends of the detection sensor main body 16 and the insulating plate 21, and the detection spring 22 is pressed by the detection sensor main body 16 and the insulating plate 21 to store energy. Insulating plate 2 corresponding to detection spring 22
1, a groove 23 is provided on the corresponding surface, and the tips of the bolts 24 inserted into the through holes of the groove 23 are arranged corresponding to the respective movable levers.
The bolt 24 is fixed to the insulating plate 21 by tightening the nut 25 inserted into the bolt 24 in the groove. Detection screw 26
A fixed cover 26 fixed to the insulating plate 21 by A surrounds the nut 24 and the insulating plate 21. By covering the tension wire portion corresponding to the detection sensor main body 16 with the insulating member instead of the insulating plate 21, the displacement detection sensor can be further reduced in size than using the insulating plate 21.
Further, an elastic member such as rubber or silicone synthetic resin may be used instead of the detection spring 22.

A fixing seat 27 fixed to the fixing cover 26 has fixing bolts 29 attached thereto by welding. After inserting the tension wire 4 into the through hole formed in the fixing bolt 29, a fixing nut 30 is attached to the fixing bolt 29, and the fixing nut 30 is tightened to fix the fixing nut 29. After the tension wire 4 is inserted into the groove formed in the vertical direction in the fixing bolt 29 instead of the through hole, that is, the tension wire 4 is inserted as shown in FIG.
To prevent the tension wire 4 from jumping out of the vertical groove. The periphery of the displacement detection sensor 15 may be covered with a synthetic resin to prevent moisture such as rain and snow from entering the inside.

Next, a method of detecting the tension of the tension wire 4 by the displacement detection sensor 15 will be described with reference to FIGS.

A detection circuit 33 is connected to the upper and lower tension wires 4, and the detection circuit 33 and each of the switches S ₁ ,
A determination circuit 34 is connected between S ₂ , S ₃ and S ₄ .
The display device 35 is connected to the determination circuit 34. Details of these circuits will be described with reference to FIG. High-frequency voltage (AC voltage 100 V, 1 kHz, 1
mA) is constantly applied to the tension wire 4. At this time, the detection circuit 33 determines that the tensions of the tension wires 4 in each section are balanced, and that the currents i ₁ and i ₂ are equal and 1 mA.
Is applied and energized. That bridge circuit, the dummy resistor Z ₂ and Z ₃ and Z ₁ and the wire side (R ₄
+ R ₃ + C + R ₁ + R ₂ ) and balance by adjusting Z ₁
The detection resistor Zp of the amplifier 26 is balanced so that substantially no current flows to the detection circuit 33.

That is, although the dummy resistors Z ₂ and Z ₃ have resistance values (R ₁ + R ₂ ) and resistance values (R ₃ + R ₄ ) on the wire side which are substantially equal, the resistance values are slightly different. is adjusted by adjusting the resistance Z ₁ when, by a current i ₁ and i ₂ the current value equal, so that no current flows in the detection resistor Zp. C acts as a coupling capacitor to pass only AC and block DC.

In this state, when the intruder 32 pushes down the tension wire 4 with the weight W, the intruder 32 comes into contact between the tension wire 4 and the ground E, via the impedance Z ₀ (= C + R) of the intruder 32. As a result, a ground current i ₃ flows from the tension wire 4 to the ground E. The ground current i ₃ passes through the ground and flows to the ground E of the detection circuit 33. Current i ₁
Also shunts to the ground current i ₃ , the balance of the bridge circuit is broken, and the current Δi = current i ₁ −ground current i ₃ flows to Zp,
The exciting coil 38 is amplified by the current Δi = current i ₁ −ground current i ₃ , which is amplified by the amplifier 36 and exceeds the threshold value of the judging device 37 by the judging device 37, the a contact 38A is closed, and L (a lamp or the like) is changed. Light.

As a result, since the bird and the intruder 32 can be distinguished, it is possible to prevent the intruder 32 from being erroneously reported as a bird as in the prior art. In particular, when the tension wire 4 is installed at a height of 2 to 4 m, and an intruder uses an aminium ladder by hanging it on the tension wire 4, a metal pole, a wet tree formed with a current passage, and the like are used as the tension wire 4. It is effective when you fall.

On the other hand, when the tension wire 4 is pulled by the weight W of the intruder 32, the tension wire 4 of R ₂ is pulled.
There moves clockwise, since the first movable lever 18A is rotated by a, rotates clogging switch lever SB closes the switch S ₃ of flowing a current to close the contacts SA, the excitation coil CR ₃ (CR ₁ , CR ₂ , CR ₄ ) are excited, the A contact CR ₃ ′ (CR ₁ ′, CR ₂ ′, CR ₄ ′) is closed, current flows through the a contact 38 A, and B (buzzer, etc.) of the display device 35 Begins to sound. The intrusion of the tension wires 4 in the areas S ₁ , S ₂ and S ₄ is the same as described above.
Description is omitted.

As a result, since the bird and the intruder 32 can be distinguished, it is possible to prevent the intruder 32 from being erroneously reported as a bird as in the prior art. In particular, when the tension wire 4 is installed at a height of 2 to 4 m, when an intruder uses a rope ladder, insulation, for example, a wooden ladder on the tension wire 4, and when a wooden pillar, a tree, etc. falls down on the tension wire 4, It is valid. L (lamp etc.)
Display device 3 under the AND condition of lighting and B (buzzer, etc.)
By doing 5, the intruder 32 can be detected more reliably.

In addition to the above-described embodiment, it is needless to say that the same effect as described above can be achieved when using the single tension wire 4 shown in FIGS.

If a loop circuit is formed by the tension wire 4 of this embodiment, when the intruder 32 comes into contact with the loop circuit and the ground E, the ground current i ₃ flows, and the intruder 32 can be easily found. Further, the present invention can be applied to a case where an intruder such as a metal pole or a wet tree having a current path contacts the loop circuit and the ground E.

Each switch S ₁ , S ₂ , S ₃ , S ₄ is shown in FIG.
5 to tension wire 4 (loop circuit)
It is set to operate when a load of more than kg is applied. As a result, even if birds such as gulls, crows, starlings, and swallows weighing 5 kg to 1 kg or less touch or stop on the wire, the switches S ₁ , S ₂ , S ₃ , and S ₄ do not operate immediately. No more false reports of intruders. Also in this case, wooden pillars, trees, etc. are tension wires 4.
It can be applied in the same manner as described above even when it falls down.

Further, the operation handle is rotated to pull the wires, and the tension wires 4 of the respective regions (resistances R ₁ , R ₂ , R ₃ , R ₄ ) are made. Whether or not each switch S ₁ , S ₂ , S
_3, if you look at whether or not S ₄ to operate, it can be immediately determined. This usually means that each switch S ₁ ,
If the operation of S ₂ , S ₃ , S ₄ is checked, there is an advantage that the tensile force of the tension wire 4 in each area can be easily found and maintenance and inspection can be easily performed.

Further, a high frequency voltage (AC voltage 100 V, 1 k
(Hz, 1 mA) is always applied to the tension wire 4, so that even if an intruder touches the tension wire 4, there is no electric shock and the intruder is safe.

As described above, according to the present invention, if the displacement detecting sensor is provided between the upper and lower tension wires, the following effects can be achieved.

(1) Regarding the effect of claim 1, a high frequency voltage (AC voltage 100 V, 1 k
Hz, 1 mA) is constantly applied to the tension wire 4, and if gravity W is applied to one side on both sides of the tension wire 4, for example, the right to the lower side, the first and second gravity are applied accordingly.
Movable lever 18A, 18B is rotated as a fulcrum spindle 17 clockwise (or counterclockwise), issued for example electrical signal first movable lever presses the second switch S _2, which places the circuit in FIG. 9 Can be detected whether gravity is applied to. In this case, since the current of the tension wire 4 was prevented from flowing to the displacement detection sensor 15 by the insulating plate 21,
The tension wire 4 can be used as a part of the displacement detection circuit, and the existing wire can be easily applied to the tension sensor. In place of the insulating plate 21, the tension wire 4 corresponding to the insulating plate 21 is insulated and coated. When a metal supporting plate is used, an insulating plate is interposed between the metal supporting plate and the tension wire 4. It is necessary to provide insulating means.

(2) Regarding the effect of the second aspect, the first switch S ₁ and the second switch S ₂ are arranged in the through hole 19 of the detection sensor main body 16 via the first movable lever 18A. Looking at the other side from one side of the through hole 19,
Since it is immediately known whether or not each switch is disposed in the through hole 19, it is possible to prevent forgetting to attach the switch. (3) Regarding the effect of claim 3, tension acts on the tension wire 4, and for example, the detection spring 22 accumulates energy while the first movable lever 18A rotates clockwise while pressing the detection spring 22, Tension wire 4
When the tension returns to the original position without working, the stored energy is released, and the first movable lever 18A can be automatically returned to the original position, so that the worker can return to the original position. There is no necessity, no undetection occurs, and the state returns to the state that can be detected at any time.

(4) Regarding the effect of the fourth aspect, the first and second movable levers 18A and 18B are shifted in the axial direction of the main shaft 17 and are disposed in opposite directions to each other. In this case, the single detection sensor body 16 can be used in common, so that the number of components can be reduced as compared with the case where the single detection sensor body 16 is not used. Can be simplified.

(5) Regarding the effect of the fifth aspect, the support plate is formed of the insulating plate 21 itself as described above, so that the number of parts at the time of assembly is reduced, assembly is facilitated, or inventory management is facilitated. There are effects such as being able to do.

(6) Regarding the effect of the sixth aspect, if the tension wire 4 corresponding to the displacement detection sensor 15 is provided with an insulating coating as described above, the displacement detection sensor can be made smaller than the first aspect. Can be

[0046] (7), the effect of claim 7, the movable lever 18A and switch to the direction of movement of the movable portion of the moving direction and the moving lever example 18A and the switches for example S ₃ of the tension wire 4 is made in the same direction since to place S ₃ to detect the sensor body 16, as compared with the case where the operation direction of the movable portion is not the same direction, can simplify pivot structure of the movable portion and the life it can be prolonged.

Further to the operation direction of the movable portion of the moving direction and the moving lever example 18A and the switches for example S ₃ of the tension wire 4 is moved or rotated in the same direction,
Since the shape of the detection sensor main body 16 can be formed in a rectangular shape whose dimension in the perpendicular direction is shorter than the dimension in the movement direction of the tension wire 4, when arranging a plurality of unit tension wires as described below, one adjacent unit tension wire is used. Since the gap between them can be narrowed, an intruder can easily get caught between the plurality of unit tension wires 4, and the intruder can be more reliably prevented from entering.

(8) Regarding the effect of claim 8, the tension wire 4 is supported by a plurality of poles 2A to 2D, and the displacement detection sensor 15 provided between the tension wires is a unit tension wire. A plurality of one unit tension wires are arranged in the width direction perpendicular to the supporting direction of the poles 2A to 2D, and when an intruder jumps over the tension wire 4 from the facility wall 1 and invades, the plurality of unit tension wires 4 must be used. Intrusion by an intruder is ensured by being hooked on one of them.

[0049]

As described above, according to the present invention, the current of the tension wire is prevented from flowing to the displacement detection sensor by the insulating portion, so that the tension wire can be used as a part of the displacement detection circuit. The existing wire can be easily applied to the tension type sensor.

[Brief description of the drawings]

FIG. 1 is a configuration diagram in which a displacement detection sensor is arranged on a tension wire according to an embodiment of the present invention.

2 (A) and 2 (B) to 2 (D) are a plan view of FIG. 1 as viewed from above and a sectional side view of FIG. 1 as viewed from the side.

3 (A), (B), (C) and (D) are a side view and a cross-sectional view of the guide roller of FIG. 1, and a side view and a cross-sectional view near an operation handle.

FIGS. 4A and 4B are explanatory diagrams illustrating the operation of the tension wire and the displacement detection sensor of FIG. 1;

FIGS. 5A and 5B are a plan view of the displacement detection sensor of FIG. 1 and a vertical cross-sectional view taken along line vv of FIG.

6A and 6B are a vertical sectional view taken along the line Vi-Vi of FIG. 5A and a sectional view taken along the line Vp-Vp of FIG. 6B.

FIG. 7 is an explanatory diagram illustrating specific operations of the tension wire and the displacement detection sensor in FIG. 1;

FIG. 8 is a circuit diagram of the tension detection circuit of FIG. 7;

FIG. 9 is an explanatory diagram illustrating specific operations of a tension wire and a displacement detection sensor according to another embodiment of the present invention.

FIG. 10 is a circuit diagram of the tension detection circuit of FIG. 9;

FIG. 11 is a characteristic diagram showing a relationship between a conventional animal and a load at the time of operation on a wire.

[Explanation of symbols]

4: tension wire, 15: displacement detection sensor, 16
... Detection sensor body, 18A ... First movable lever, 18B ...
Second movable lever, 21: insulating plate, S ₁ : first switch,
S ₂ ... the second switch, S ₃ ... the third switch, S ₄ ... fourth switch.

──────────────────────────────────────────────────続 き Continued from the front page (72) Inventor Shigeo Shiono 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside the Kokubu Plant of Hitachi, Ltd. (56) References JP-A-55-97688 (JP, A) JP-A-62-162194 (JP, A) JP-A-6-348971 (JP, A) JP-A-5-298565 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G08B 13/12 G01B 7/00 G01V 9/00

Claims (8)

(57) [Claims] 1. A support plate is disposed at one end of a detection sensor main body, and a tension wire extending through one side of the support plate and a movable lever that rotates in response to movement of a tension wire fixed to the support plate are detected. A movable lever, which extends into the sensor body and is rotatably inserted into a main shaft penetrating the detection sensor body, rotates about the main shaft as a fulcrum in the direction of movement of the tension wire, and pushes the movable lever in the direction of rotation of the movable lever. Two switches for turning on and off the contacts by pressure are fixed to the detection sensor main body, and insulating means for preventing a current from the tension wire from flowing through the support plate to the detection sensor main body is provided. Displacement detection sensor. 2. A support plate is disposed at one end of a detection sensor main body, and a tension wire extending through one side of the support plate and a movable lever that rotates in response to movement of a tension wire fixed to the support plate are detected. A movable lever that extends into the sensor body and is rotatably inserted into a main shaft that penetrates through the inside of the detection sensor body rotates about the main shaft as a fulcrum in the direction of movement of the tension wire, and the pressing force of the movable lever in the direction of rotation of the movable lever. The two switches for turning on and off the contacts are fixed to the through holes provided in the detection sensor main body, and insulating means for preventing the current from the tension wire from flowing to the detection sensor main body via the support plate is provided. Characteristic displacement detection sensor. 3. A support plate is arranged at one end of the detection sensor main body, and a tension wire extending through one side of the support plate and a movable lever that rotates in accordance with the movement of the tension wire fixed to the insulating plate are detected. A movable lever that extends into the sensor body and is rotatably inserted into a main shaft that penetrates through the inside of the detection sensor body rotates about the main shaft as a fulcrum in the direction of movement of the tension wire, and the pressing force of the movable lever in the direction of rotation of the movable lever. Two switches for turning the contacts on and off are fixed to the detection sensor main body, and insulating means for preventing current from the tension wire from flowing through the support plate to the detection sensor main body is provided. When tension is applied to the tension wire between itself and the support plate, the support plate accumulates energy by the force that presses the detection sensor main body, and the tension wire has no tension. The displacement detection sensor further comprises an elastic member that returns the movable lever to its original position with a pressing force that releases the accumulated energy when the support plate presses the detection sensor main body. 4. A tension lever extending through one side of a support plate disposed at both ends of the detection sensor main body, and a movable lever that rotates in accordance with the movement of the tension wire fixed to each support plate is provided in the detection sensor main body. The two movable levers rotatably inserted into the main shaft extending through the inside of the detection sensor body rotate in the direction of movement of the tension wire with the main shaft as a fulcrum, and the pressing force of the movable lever in the direction of rotation of each movable lever. 4. The device according to claim 1, wherein four switches for turning on and off the contacts are fixed to the detection sensor main body, and insulating means for preventing a current from the tension wire from flowing to the detection sensor main body via the support plate is provided. The displacement detection sensor according to any one of claims 1 to 3. 5. The displacement detection sensor according to claim 1, wherein the support plate is formed of an insulating member. 6. A tension wire portion corresponding to the support plate is covered with an insulating member.
The displacement detection sensor according to any one of claims 1 to 4. 7. The movable lever and each switch are arranged on the detection sensor main body so that the direction of movement of the tension wire and the direction of operation of the movable portion of the movable lever and each switch are in the same direction. The displacement detection sensor according to any one of claims 1 to 6. 8. The tension wire is supported by a plurality of poles, and a displacement detection sensor provided between the tension wires is defined as one unit tension wire. The displacement detection sensor according to any one of claims 1 to 7, wherein the displacement detection sensor is disposed in a direction perpendicular to the width of the sword.