JPH09286334A - Breakage detecting device for crossing gate lever - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably detect the presence of a crossing gate lever even when the raising position of the crossing gate lever is slightly changed by a method wherein the breakage of the crossing gate lever is detected based on a sensor signal outputted from a crossing gate lever sensor. SOLUTION: A breakage detecting device 1 for a crossing gate lever is provided with a crossing gate lever sensor located in a sensor box 2 and detecting a crossing gate lever 3. The crossing gate lever sensor arranged in the sensor box 2 consists of a sensor, a switch element, a photo sensor, a magnetic sensor, and an acoustic sensor, which utilize electromagnetic coupling. The crossing lever 3 is detected and generates a sensor signal. As noted above, when the tip part of the crossing gate lever is contained in the sensor box, even when the position of the crossing gate lever is slightly changed, high damping does not occur to a sensor signal and the crossing gate lever is reliably detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breaking rod breakage detecting device for detecting breaking breakage of a breaking rod of a breaking machine provided at a railroad crossing or a parking lot.

[0002]

2. Description of the Related Art In a conventional breakage detecting device for a breaking rod,
While placing the infrared sensor near the rising position of the blocking rod,
A light-reflecting sheet is wrapped around the tip of the blocking rod, and when the blocking rod is located near the raised position, infrared rays are emitted from the light emitting section of the infrared sensor and the infrared rays reflected from the light reflecting sheet of the blocking rod are received by the infrared sensor. Configured to receive light with
It is known to detect the presence or absence of a blocking rod based on the light receiving level of a light receiving unit.

In the conventional breakage detecting device for a breaking rod constructed as described above, for example, when the light receiving level of the light receiving portion exceeds a reference value, the tip of the breaking rod is located near the infrared sensor (ascending position). It is determined that there is no breakage of the blocking rod. On the other hand, if the received light level is less than the reference value, it is determined that there is no tip of the blocking rod near the infrared sensor (up position) and there is no breaking of the blocking rod. Can be detected.

FIG. 8 is a layout view of a conventional breakage detecting device for a railroad crossing blocking rod. In FIG. 8, a conventional railroad crossing blocking rod breakage detection device 50 includes an infrared light emitting section 51, an infrared light receiving section 52, a transmitter for generating an electric signal for causing the infrared light to be emitted from the light emitting section 51, and a light receiving section 52. A detector 53 for detecting the electric signal received and converted is provided, and the detector 53 is attached to a column 54 installed near the breaker 55.

On the other hand, the railroad crossing blocking rod 56 of the circuit breaker 55 is fixed by winding a reflection sheet 57 having a high light reflectance around the tip end thereof, and is driven by the circuit breaker 55 from an elevated position which is a normal fixed position to a train or the like. Repeatedly move to the descending position when
It is set so as to be in the vicinity of the breakage detection device 50 of the railroad crossing blocking rod at the raised position.

When the railroad crossing blocking rod 56 is in the raised position, the breakage detecting device 50 for the railroad crossing blocking rod causes the light emitting section 51 to send out infrared rays at a constant cycle, and the reflecting sheet 5 of the railroad crossing blocking rod 56.
Infrared rays reflected from 7 are received by the light receiving section 52, and the detection section 53 compares the received light level with a preset reference value. When the level of the received light is less than the reference value and the level crossing blocking rod 56 cannot be detected, the level crossing blocking rod is detected. It is configured to detect 56 breakages.

[0007]

A conventional breakage detecting device 50 for a railroad crossing blocking rod uses infrared rays to detect the railroad crossing blocking rod 56 and directs it toward a reflection sheet 57 provided at the tip of the railroad crossing blocking rod 56. To emit infrared rays, and the reflection sheet 57
The infrared ray reflected from the infrared ray is received, and the presence or absence of the railroad crossing blocking rod 56 is determined based on the received light level. Therefore, the infrared ray emitting section 51 and the light receiving section 52, and the reflection sheet 57.
There is a problem that the initial setting of the positional relationship of is difficult and the adjustment work requires a lot of time.

Further, since the railroad crossing blocking rod 56 is usually formed in a cylindrical shape, if the rising position of the railroad crossing blocking rod 56 deviates even a little due to the change of the driving force of the breaker 55 for driving the railroad crossing blocking rod 56 with time, the reflection sheet. Despite the fact that the reflected light of the infrared rays reflected from 57 is greatly reduced and the railroad crossing blocking rod 56 is in the raised position, the breakage detecting device 50 for the railroad crossing blocking rod detects the breakage of the railroad crossing blocking rod 56. There are challenges.

Further, when the railroad crossing blocking rod 56 is shaken by the wind and the position of the railroad crossing blocking rod 56 is changed, the reflected light of infrared rays reflected from the reflection sheet 57 is greatly reduced, and the breakage detecting device 50 of the railroad crossing blocking rod is closed. There is a problem of detecting breakage of the rod 56.

The present invention has been made to solve the above problems, and its purpose is to change the driving force of a circuit breaker over time.
Or, to provide a highly reliable breakage detection device for a blocking rod that can reliably detect the presence or absence of the railway crossing rod 56 even if the elevated position of the railway crossing rod changes slightly due to changes in environmental conditions such as wind. It is in.

[0011]

In order to solve the above-mentioned problems, a breakage detecting device for a breaking rod according to the present invention detects a breaking box within the sensor box and a sensor box for accommodating the tip of the breaking rod. And a breaking rod sensor for detecting breaking of the breaking rod based on a sensor signal output from the breaking rod sensor.

In the breakage detecting device of the blocking rod according to the present invention, the sensor box for accommodating the tip of the blocking rod is provided and the blocking rod sensor is provided in the sensor box. -When housed in the box, even if the position of the blocking rod changes a little, the sensor signal will not be greatly attenuated, and the blocking rod can be reliably detected.

According to a second aspect of the present invention, there is provided a breaking rod sensor, which comprises an oscillating circuit having a coil resonance circuit, wherein a magnetic material is arranged at the tip of the breaking rod to cause electromagnetic coupling when the breaking rod is housed in the sensor box. Is used to detect the shutoff rod.

According to a second aspect of the present invention, there is provided a breaking rod sensor, wherein a magnetic material is arranged at the tip of the breaking rod and electromagnetic coupling occurs when the breaking rod is housed in the sensor box. Since the oscillating frequency of the oscillating circuit having the circuit changes, the breaking rod can be detected.

According to a third aspect of the present invention, there is provided a shutoff rod sensor in which a resonant circuit is arranged at the tip of the shutoff rod, and when the shutoff rod is housed in the sensor box, the frequency of the oscillation circuit changes.
It is characterized by detecting a blocking rod.

According to a third aspect of the present invention, there is provided a cutoff rod sensor, wherein a resonance circuit is arranged at a tip of the cutoff rod, and when the cutoff rod is housed in the sensor box, the oscillation circuit having the coil resonance circuit and the resonance circuit resonate. Then, the oscillation frequency of the oscillation circuit changes, so that the interruption rod can be detected.

According to a fourth aspect of the present invention, there is provided a shutoff rod sensor which comprises a mechanical switch element, and when the shutoff rod is housed in a sensor box, the switch element operates to detect the shutoff rod. .

Since the shutoff rod sensor according to the fourth aspect is configured by a mechanical switch element and is arranged in the sensor box, the switch element operates when the shutoff rod is housed in the sensor box, and the shutoff rod is operated. Can be detected.

According to a fifth aspect of the present invention, there is provided a shutoff rod sensor,
It is characterized in that it comprises an optical sensor composed of a light emitting portion and a light receiving portion which are arranged so as to face each other in the box, and when the blocking rod is housed in the sensor box, it blocks the light and detects the blocking rod.

According to a fifth aspect of the present invention, there is provided a shutoff rod sensor which comprises an optical sensor including a light emitting portion and a light receiving portion.
Since the blocking rod is arranged so as to face the gap between the boxes, when the blocking rod is housed in the sensor box, the blocking rod can block the light to detect the blocking rod.

According to a sixth aspect of the present invention, there is provided a shutoff rod sensor which comprises a magnetic sensor. When the shutoff rod is housed in a sensor box, the shutoff rod is detected by detecting a magnetic field of a magnet provided on the shutoff rod. Characterize.

A shutoff rod sensor according to a sixth aspect of the present invention is composed of a magnetic sensor, and when a magnet provided on the shutoff rod is housed in a sensor box, detects a magnetic field and outputs a sensor signal,
A blocking rod can be detected.

A shutoff rod sensor according to a seventh aspect is a sensor
It is characterized by comprising a speaker and a microphone arranged to face each other in the box, and when the blocking rod is housed in the sensor box, it blocks the sound wave and detects the blocking rod.

According to the seventh aspect of the present invention, the shutoff rod sensor is composed of a speaker and a microphone and is arranged so as to face a gap between the sensor boxes having a short distance. Therefore, when the shutoff rod is housed in the sensor box, the shutoff rod sensor is arranged. It is possible to detect the blocking rod by blocking the sound wave.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. In the embodiments described below, the case where the present invention is applied to a railroad crossing blocking rod will be described. FIG. 1 is a layout view of a breakage detection device for a railroad crossing blocking rod to which the present invention is applied. In FIG. 1, a breakage detection device 1 for a railroad crossing blocking rod is equipped with a sensor box 2 that houses the tip of the railroad crossing blocking rod 3 when the railroad crossing blocking rod 3 is in a substantially vertical position, and is installed near the barrier 5. It is attached to the pillar 4.

Further, the breakage detecting device 1 of the railroad crossing blocking rod is provided with a railing rod sensor for detecting the railroad crossing rod 3 in the sensor box 2, and the rail rod sensor is constructed by connecting a wire connected along the column 4. A detection device (not shown) that is connected via a device is provided.

The sensor box 2 is formed in a U shape with one side open, and when the railroad crossing blocking rod 3 which reciprocates in the direction of the arrow by the drive of the breaker 5 moves from the horizontal position to the vertical position, Position adjustment is performed so that the tip end of the railroad crossing blocking rod 3 is housed inside the U-shape.

The shutoff rod sensor provided in the sensor box 2 is a sensor utilizing electromagnetic coupling, a switch element,
When the tip of the railroad crossing blocking rod 3 is housed in the U-shaped inside of the sensor box 2, it is composed of an optical sensor, a magnetic sensor, an acoustic sensor, etc., and the railroad crossing blocking rod 3 is detected to output a sensor signal. appear. The reason for detecting the tip of the railroad crossing blocking rod 3 is that the railroad crossing blocking rod 3 is broken or bent.
This is because the effect of bending or bending is likely to appear at the tip.

Further, since the sensor box 2 is formed in a U shape, when the tip end of the railroad crossing blocking rod 3 is accommodated, the position change due to the influence of wind or the like is small, and the sensor box
The rail crossing rod 3 can be detected with high sensitivity by the rail rod sensor arranged in the box 2.

The railroad crossing bar 3 is treated as a consumable item, and only when the rail bar sensor is constituted by a sensor utilizing electromagnetic coupling or a magnetic sensor, a magnetic material, a resonance circuit or a magnetic body corresponding to the sensor is attached to the tip of the rail crossing bar 3. A magnet is attached, and in the case of a switch element, an optical sensor, an acoustic sensor, etc., it is composed of a simple rod.

FIG. 2 is a block diagram of the essential parts of an embodiment of a breakage detecting device for a railroad crossing blocking rod to which the present invention is applied. In FIG. 2, the breakage detection device 1 for the railroad crossing blocking rod is a sensor
The box rod 2 is provided with a shutoff rod sensor 7, an interface circuit 11 constituting a detection device, a timing pulse generation means 12, a comparator 13, a judgment means 14, and a display means 15.

The shutoff rod sensor 7 is composed of a sensor utilizing electromagnetic coupling, a switch element, an optical sensor, a magnetic sensor, and an acoustic sensor. When the tip of the railroad crossing shutoff rod 3 is housed in the sensor box 2. The detection operation is performed, and the analog sensor signal S _A is supplied to the interface circuit 11.

The interface circuit 11 is composed of an FV (frequency-voltage) conversion circuit, an AD converter, etc., and an analog sensor signal based on the timing pulse T _P constantly supplied from the timing pulse generation means 12. S _A is taken in at a predetermined cycle, F-V (frequency-voltage) conversion or A-
The digital sensor signal S _D corresponding to the sensor signal S _A after D conversion is provided to the comparator 13.

The comparator 13 is composed of a differential amplifier or the like, and compares the result of comparison between the sensor signal S _D provided from the interface circuit 11 and a preset reference value S _{K with} the crossing of the breaker 5 shown in FIG. The drive signal (not shown) generated when the rod 3 is driven to the vertical position is conditionally judged, and the comparison signal C _M
Is supplied to the determination means 14.

The judging means 14 has a display drive circuit, and when the comparison signal C _M is supplied from the comparator 13, the railroad crossing blocking rod 3 is provided.
Determination signal representing the breakage H _O occurs, drives the display unit 15.

That is, when the circuit breaker 5 drives the railroad crossing blocking rod 3 to the vertical position and the tip of the railroad crossing blocking rod 3 is in the sensor box 2, the sensor signal S _D exceeds the reference value S _K. Although the railroad crossing blocking rod 3 is not broken, but when the front end is not inside the sensor box 2, a display is displayed to notify that the railroad crossing blocking rod 3 is broken.

The display means 15 provides an audible display such as a buzzer and voice synthesis, a visual display such as a lamp and a display, and notifies the breakage of the railroad crossing blocking rod 3.

As described above, the breakage detecting device for the railroad crossing blocking rod according to the present invention includes a sensor for accommodating the tip of the railroad crossing blocking rod.
Since the box is provided and the shutoff rod sensor is provided inside the sensor box, if the tip of the railroad crossing shutoff rod is housed in the sensor box, even if the position of the railroad crossing shutoff rod changes a little, the sensor signal will be greatly attenuated. It is possible to reliably detect the railroad crossing blocking rod without being generated.

FIG. 3 is a block diagram of a shutoff rod sensor according to the second or third aspect. FIG. 3A shows an embodiment in which a magnetic material is arranged at the tip of the railroad crossing blocking rod, and FIG. 3B shows an embodiment in which a resonance circuit is arranged at the front end of the railroad crossing blocking rod. In FIG. 3A, an LC oscillating circuit 16 having a coil resonance circuit is arranged in the sensor box 2, and when the tip of the railroad crossing blocking rod 3 is housed in the sensor box 2, the railroad crossing blocking rod is provided. When the magnetic body 17 arranged at the tip of the coil 3 approaches the coil resonance circuit, the inductance of the coil resonance circuit of the LC oscillation circuit 16 changes due to electromagnetic coupling. The cushioning material 6 is provided to absorb the shock when the railroad crossing blocking rod 3 is housed in the sensor box 2.

When the inductance of the coil resonance circuit changes, the oscillation frequency of the LC oscillation circuit 16 changes, so
The railroad crossing blocking rod 3 can be detected by detecting a change in the oscillation frequency of the sensor signal S _A.

The sensor signal S _A whose oscillation frequency has changed is
The voltage is converted by the FV converter that constitutes the interface 11 shown in FIG. 2, and is detected as a digital sensor signal S _D via the AD converter.

Once the railroad crossing blocking rod 3 is housed in the sensor box 2, the position of the railroad crossing blocking rod 3 slightly changes due to changes in the driving force of the barrier 5 with time and environmental changes such as wind. Has little effect on the sensor signal S _D.

As described above, in the shutoff rod sensor according to the second aspect of the invention, the magnetic box is arranged at the tip of the railroad crossing shutoff rod, and the magnetic coupling occurs when the railroad crossing shutoff rod is housed in the sensor box. Since the oscillation frequency of the oscillation circuit having the coil resonance circuit provided therein changes, it is possible to detect the railroad crossing blocking rod.

In addition, in FIG.
LC oscillator circuit 1 having a coil resonance circuit in box 2
6 is arranged, and when the tip end of the railroad crossing blocking rod 3 is accommodated in the sensor box 2, the resonance circuit 25 arranged at the front end of the railroad crossing blocking rod 3 and the LC oscillation circuit 1 of the sensor box 2 are arranged.
Due to the resonance with 6, the oscillation frequency of the LC oscillation circuit 16 changes to the resonance frequency of the resonance circuit 25.

In the resonance circuit 25, for example, an inductance and a capacitor are connected in parallel to form a resonance circuit, and the resonance frequency of the resonance circuit is set near the oscillation frequency of the LC oscillation circuit 16. However, although the resonance frequency is close to the oscillation frequency, the detection device distinguishes both frequencies and sets them to a value that allows detection.

As described above, in the breaking rod sensor according to the third aspect, the resonance circuit is arranged at the tip of the breaking rod so that when the breaking rod is housed in the sensor box, it is resonated with the oscillation circuit having the coil resonance circuit. Since the circuit resonates and the oscillation frequency of the oscillation circuit changes, the interruption rod can be detected.

The sensor box 2 accommodating the LC oscillating circuit 16 of claim 2 or claim 3 is not necessarily limited to the U-shape. Further, the LC oscillation circuit 16 of claims 2 and 3 can be installed on the surface of the earth or underground.

FIG. 4 is a block diagram of a shutoff rod sensor according to a fourth aspect of the present invention. In FIG. 4, the sensor box 2 includes a plurality of mechanical switch elements 18A as a shutoff rod sensor,
18B is arranged, and when the tip of the railroad crossing blocking rod 3 is housed in the sensor box 2, the tip operates one or both of mechanical switch elements 18A and 18B to generate a sensor signal S _A. To do.

The mechanical switch elements 18A, 18B are connected in series or in parallel, and even if the railroad crossing blocking rod 3 is accommodated in the sensor box 2 in a biased manner, the switch elements 18A, 18B are connected.
It is arranged so that either one of 8B operates. When the switch elements 18A and 18B are connected in series, a switch having a normal make contact structure is used as the switch elements 18A and 18B, and one of the switch elements is brought into a break state by the railroad crossing blocking rod 3 so that a circuit is formed. Is detected to detect the railroad crossing blocking rod 3. Further, it is also possible to arrange three or more switch elements in series connection or parallel connection so as to reliably detect where the railroad crossing blocking rod 3 is located in the sensor box 2.

As described above, since the shutoff rod sensor according to the fourth aspect is constituted by the mechanical switch element and arranged in the sensor box, the switch element is accommodated when the railroad crossing shutoff rod is housed in the sensor box. It can be operated to detect a railroad crossing blocking rod.

FIG. 5 is a block diagram of a shutoff rod sensor according to a fifth aspect. In FIG. 5, an optical sensor consisting of a light emitting portion 19 and a light receiving portion 20 is arranged facing each other in the sensor box 2, and when the railroad crossing blocking rod 3 is housed in the sensor box 2, the railroad crossing blocking rod 3 is illuminated. By blocking (for example, infrared rays), the change (attenuation) of the optical signal S _L received by the light receiving unit 20 is detected and the sensor signal S _A is output.

The light emitting unit 19 and the light receiving unit 20 are sensors,
Since they are arranged on the side wall of the box 2 so as to face each other with a narrow gap, the scattering of the optical signal S _L is small, and the change of the optical signal S _L blocked by the railroad crossing blocking rod 3 is detected with high sensitivity by the light receiving unit 20. be able to.

As described above, since the shutoff rod sensor according to the fifth aspect is composed of the optical sensor including the light emitting portion and the light receiving portion and is arranged to face the gap of the sensor box having a short distance,
When the railroad crossing blocking rod is housed in the sensor box, the railroad crossing blocking rod can block light to detect the railroad crossing blocking rod with high sensitivity.

FIG. 6 is a block diagram of a shutoff rod sensor according to a sixth aspect of the present invention. In FIG. 6, a magnetic sensor composed of, for example, a Hall element 21 is arranged in a sensor box 2, a permanent magnet 22 is attached to the tip of the railroad crossing blocking rod 3, and the tip of the railroad crossing blocking rod 3 is a sensor. When housed in the box 2, the magnetic field generated by the permanent magnet 22 is detected and the Hall voltage generated from the Hall element 21 is output as the sensor signal S _A.

Further, instead of the Hall element 21, a magnetoresistive element whose resistance value increases by detecting a magnetic field can be used for the magnetic sensor.

As described above, the shutoff rod sensor according to the sixth aspect is composed of a magnetic sensor, and when the magnet provided on the railroad crossing shutoff rod is housed in the sensor box, the magnetic field of the magnet is detected and a sensor signal is output. However, the railroad crossing blocking rod can be detected.

The sensor box 2 accommodating the Hall element 21 of claim 6 is not necessarily limited to the U-shape.

FIG. 7 is a block diagram of a shutoff rod sensor according to a seventh aspect of the present invention. In FIG. 7, a speaker 23 as a sound source and a microphone 24 as an acoustic pickup are arranged so as to face each other in the sensor box 2, and a sound wave S is transmitted from the speaker 23 and a sound wave S is received by the microphone 24.

Since the speaker 23 and the microphone 24 are arranged so as to face each other in the narrow gap of the sensor box 2,
The sound wave S received by the microphone 24 is less attenuated.

When the railroad crossing blocking rod 3 is housed in the sensor box 2, the railroad crossing blocking rod 3 blocks the sound wave S, so that the reception level of the sound wave S received by the microphone 24 is attenuated,
Compared with the case where the railroad crossing blocking rod 3 is not housed, the change in the sensor signal S _A of the sound wave S becomes large, and the railroad crossing blocking rod 3 can be detected.

As described above, since the blocking rod sensor according to the seventh aspect comprises the speaker and the microphone and is arranged so as to face the gap between the sensor boxes having a short distance, the railroad crossing blocking rod is housed in the sensor box. Then, the sound wave can be blocked by the railroad crossing blocking rod to detect the railroad crossing blocking rod.

In the embodiment of the present invention, the sensor box 2 is provided at a position where the railroad crossing blocking rod 3 is vertical to accommodate the tip end of the railroad crossing blocking rod 3, but the railroad crossing blocking rod 3 is horizontal. It may be provided at such a position to accommodate the tip end of the railroad crossing blocking rod 3.

Although the embodiment of the present invention has shown an example in which the present invention is applied to a railroad crossing blocking rod, the present invention is not limited to the railroad crossing blocking rod, and is generally applicable to a railing crossing rod of a parking system. It can be applied to a general shutoff rod.

[0064]

As described above, the breakage detecting device for a blocking rod according to the present invention is provided with a sensor box for accommodating the tip of the blocking rod, and a blocking rod sensor is provided in the sensor box. If the tip of the is housed in the sensor box, even if the position of the shutoff rod changes slightly, the sensor signal will not be greatly attenuated, and the shutoff rod can be detected reliably, improving reliability. You can

Further, since no special sensor or detection circuit is mounted on the breaking rod, the breaking rod can be treated as a consumable item, so that the running cost of the device can be reduced.

Further, an electromagnetic coupling, a mechanical switch, an optical sensor, a magnetic sensor, or an acoustic sensor can be used as the blocking rod sensor, so that a sensor optimal for the environment, application, and cost can be constructed.

Therefore, it is possible to provide a breakage detection device for a breaking rod which can cope with changes in environmental conditions and has high sensitivity and high reliability.

[Brief description of drawings]

FIG. 1 is a layout view of a breakage detection device for a railroad crossing blocking rod to which the present invention is applied.

FIG. 2 is a block diagram of the essential parts of an embodiment of a breakage detection device for a railroad crossing blocking rod to which the present invention is applied.

FIG. 3 is a configuration diagram of a shutoff rod sensor according to claim 2 or 3;

FIG. 4 is a block diagram of a shutoff rod sensor according to claim 4;

FIG. 5 is a configuration diagram of a shutoff rod sensor according to claim 5;

FIG. 6 is a configuration diagram of a shutoff rod sensor according to claim 6;

FIG. 7 is a configuration diagram of a shutoff rod sensor according to claim 7;

FIG. 8 is a layout view of a conventional breakage detection device for a railroad crossing blocking rod.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fracture detection device for railroad crossing blocking rod, 2 ... Sensor box, 3 ... Railroad crossing blocking rod, 4 ... Struts, 5 ... Breaker, 6 ... Cushioning material, 7 ... Blocking rod sensor, 11 ... Interface circuit, 1
2 ... Timing pulse generating means, 13 ... Comparator, 14 ...
Judgment means, 15 ... Display means, 16 ... LC oscillation circuit, 17
... magnetic material, 18A, 18B ... switch, 19 ... light emitting part,
20 ... Light receiving part, 21 ... Hall element, 22 ... Magnet, 23 ...
Speaker, 24 ... Microphone, 25 ... Resonance circuit, C _M
... Comparison signal, H _O ... Judgment signal, S _A , S _D ... Sensor signal,
T _P ... Timing pulse.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display area G01V 9/00 G01V 3/00 E 8/10 9/04

Claims (7)

[Claims] 1. A breakage detection device for a breakage bar that detects breakage of a breakage bar (3), comprising: a sensor box (2) accommodating a tip of the breakage bar (3); and a sensor box (2). A shutoff rod sensor (7) for detecting the shutoff rod (3), and detecting breakage of the shutoff rod (3) based on a sensor signal output from the shutoff rod sensor (7). A device for detecting breakage of the breaking rod. 2. The breaking rod sensor (7) is composed of an oscillating circuit (16) having a coil resonance circuit, and a magnetic body (17) is arranged at the tip of the breaking rod (3). The breakage detecting device for a breaking rod according to claim 1, wherein the breaking rod (3) is detected by an electromagnetic coupling that occurs when (3) is housed in the sensor box (2). 3. The breaking rod sensor (7) is composed of an oscillating circuit (16) having a coil resonance circuit, and a breaking circuit (25) is arranged at the tip of the breaking rod (3). 2. The shutoff rod according to claim 1, wherein the shutoff rod (3) is detected by a frequency change of the oscillation circuit (16) caused when the (3) is housed in the sensor box (2). Breakage detection device. 4. The shutoff rod sensor (7) comprises a mechanical switch element (18A, 18B), and the switch when the shutoff rod (3) is housed in the sensor box (2). The breakage detecting device for a breaking rod according to claim 1, wherein the element (18A, 18B) operates to detect the breaking rod (3). 5. The shutoff rod sensor (7) is a light emitting part (1) arranged to face the inside of the sensor box (2).
9) and a light receiving unit (20), and when the blocking rod (3) is housed in the sensor box (2), it blocks light and detects the blocking rod (3). The breakage detecting device for a blocking rod according to claim 1, wherein: 6. The shutoff rod sensor (7) is composed of a magnetic sensor (21), and when the shutoff rod (3) is housed in the sensor box (2), the shutoff rod (3) is attached to the shutoff rod (3). 2. The breakage detecting device for a breaking rod according to claim 1, wherein the breaking rod (3) is detected by detecting a magnetic field of a magnet (22) provided. 7. The shutoff rod sensor (7) comprises a speaker (2) arranged in the sensor box (2) so as to face each other.
3) and a microphone (24), and when the shutoff rod (3) is housed in the sensor box (2), the soundwave is shut off to detect the shutoff rod (3). The breakage detection device for a blocking rod according to claim 1.