JPH0830736B2 - Earthquake detector protection 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 seismic-electrical converter (hereinafter referred to as seismic converter) and a data processing device which are connected to each other via a cable.

[0002]

[Technical background] To prevent disasters due to earthquakes,
Earthquake detectors will be installed in the dam, dam, etc. below the building's elevator facility. The seismic detector device consists of a portion for converting the seismic into an electric signal, a transmission line you transmit this signal to eliminate the disturbance (noise), and data processing apparatus for recording and processing the transmitted signals.

An example of converting the earthquake into an electric signal will be described with reference to the principle diagram shown in FIG. 3. First, in the seismic converter A, the coil 3 is at the center and a slight air gap is provided around it. An earthquake sensor 1 is formed by arranging a cylindrical bottomed permanent magnet 2. Here, the coil 3 is suspended in the center of the permanent magnet 2 and is made of iron which forms a magnetic circuit.
It is fixed to the yoke (frame) . Further, this seismic sensor 1 is designed to separately detect vibrations in two horizontal directions (XY directions) and vertical directions (Z directions), and detect the vibrations in the horizontal X direction, horizontal Y direction and vertical Z direction. The three-component converter of (3) is housed in the metal casing 4 via the cushion layer 5 made of a polymer material or an air gap that also serves as an electric insulation means and a vibration protection means.

The signal from the seismic sensor 1 is shielded from the signal insulating core wire 11 for each core so as not to pick up disturbance (noise), or a signal cable in which the signal insulating core wire 11 is shielded collectively. (Instrumentation cable) a is transmitted to the data processing device B. Also, the coil 3 of the seismic sensor 1
In order to shield the
The shield of the signal cable a is connected.

In the data processing device B, a processing unit 14 is housed in a casing 13, and the processing unit 14 and the shield of the signal cable a are grounded.

[0006]

However, in the above-mentioned prior art, when a lightning surge occurs, a large potential difference cannot be dealt with only by the cable shielding, and a large potential difference is generated between the ground surface portion and the seismic transducer A buried underground. And a lightning surge
Instantly I run <br/> from the casing 4 of the seismic transducer A seismic sensor 1, a potential difference occurs between the frame and the coil 3,
There was damage such as burning of the coil 3.

Further, each core 11 of the cable a does not pick up a disturbance (noise) due to the shielding, but it is not a so-called disturbance (noise) but a surge other than a lightning strike causes the signal processing data to be included in the signal processing data. Abnormal waveform Q as shown in Figure 4
Was appearing. The abnormal waveform Q causes, for example, the elevator or escalator of the building to unintentionally make an emergency stop when the earthquake detection device is installed underground as a safety device of the building.

In view of the above points, an object of the present invention is to protect the seismic converter and its signal transmission path data processing device from lightning surges, and to prevent abnormal voltage generated in the ground from being picked up. .

[0009]

In order to solve the above problems, according to the present invention , a coil is suspended in the air from a permanent magnet.
Seismic sensor in the casing with air gap or protection
The seismic transducer installed via a cushion layer and the carp
In a seismic detection system in which a signal transmission cable is connected to a data processing device that records and processes signals from the cable, the transmission cores of the signal transmission cable are shielded for each core or collectively, and around it A shield layer is provided via an insulating layer, and the inner shield layer has one end connected to the frame of the seismic sensor of the seismic transducer,
The other end is grounded through the data processing device, and the outer shield layer is grounded at one end through the seismic converter casing and the other end through the data processing device casing. I did.

[0010]

According to the present invention constructed as described above, the surge caused by lightning strike is grounded through the casings of the seismic converter and the data processing device without time lag by the outer shield layer whose both ends are grounded, and There is no potential difference between the part and the seismic converter. Therefore, there is no failure such as coil burning of the seismic converter. Further, the abnormal voltage generated in the ground is reliably shielded by the double shield layer so that it is not picked up and good seismic data can be obtained.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment is shown in FIG. 1, in which reference numeral 1 is an earthquake sensor forming an essential part of the seismic converter A, which is a small amount inside a cylindrical magnet 2 having a circular hole inside. The coil 3 is suspended in the air with a gap, and is housed in a metal casing 4 with a protective cushion layer 5 interposed therebetween. Magnet 2, as shown in FIG.
It is fixed to a frame forming a magnetic circuit (not shown), and an unbottomed one can also be used.

The seismic sensor 1 is composed of three components for detecting vibrations in the horizontal X-Y direction and the vertical Z direction, as in the conventional case, and these three components are collectively stored in the casing 4. Therefore, although the number of lead wires 12 is two in the figure, there are actually six.

The seismic sensor 1 is connected with a double shielded dual sheath instrumentation cable P having the structure shown in FIG. The connection of the instrumentation cable P to the seismic converter A is performed by the outer sheath 6 and the outer shield (shield).
7, inner sheath 8, inner shield 9, presser tape 1
0, the signal core wire 11 is stripped off, the outer shield 7 is in the casing 4, and the inner shield 9 is the seismic sensor 1
The signal core wire 11 on the frame (magnet 2) of the seismic sensor 1
The watertight treatment is performed at a place where the cable P is drawn out from the casing 4 although not shown in the drawing.

[0014]

[Table 1]

[0015]

[Table 2]

On the other side of the instrumentation cable P, the outer shield 7 of the instrumentation cable P has the same construction as that of the conventional data processor B.
Of the metal casing 13, the inner shield 9 is grounded through the processing member, and the signal core wire 11 is connected to the terminal of the processing unit 14.

The internal shield 9 of the instrumentation cable P is used.
If the drain wire 15 is routed to the shield 9 and the magnet 2,
Can be connected via the drain wire 15,
The work becomes easy. Although the outer shield 7 is a tin-plated braid, it is more effective if a corrugated pipe is used instead. In the figure, 16 is an interposition, 17 is an interposition cord, R is a gas arrester, and has a rating of 20KA.
The arrester R can be appropriately provided at a required position between the casings 4 and 13 and the core wire 11, between the core wires 11 and between the magnet 2 and the core wire 11, for example, only between the casing 4 and the core wire 11, Further, it is not always necessary to provide it.

This embodiment is constructed as described above, and the seismic converter A is embedded in the foundation of the flood control dam, in the dam core or in the boring hole, at a position of 300 to 500 m underground or under the elevator of various buildings. . This earthquake converter A
The cable P allows the detection signal to be transmitted to the data processing device B on the ground.

The seismic transducer A, the cable P, and the data processing device B having this structure are installed in the Shimokita area of Aomori prefecture where there are many natural lightning strikes.
Although the sample facility was set up and the filled test has been continued for about 3 years, no problems occurred and no abnormal waveform Q was found.

Although the embodiment has been described in the case of detecting an earthquake, the present invention can be applied to the detection of landslide and the like by detecting the crust pressure, and the effect can be obtained.

[0021]

Since the present invention is constructed as described above,
Effectively protect earthquake converters, transmission cables, etc. from lightning surges and abnormal surges. Therefore, it is possible to accurately detect the occurrence of an earthquake.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an embodiment.

FIG. 2 is a sectional view of an instrumentation cable.

FIG. 3 is a schematic view of a conventional example.

[Figure 4] Abnormal surge waveform diagram

[Explanation of symbols]

 A earthquake-electric converter B data processing device P instrumentation cable 1 seismic sensor 2 magnet 3 coil 4 casing 5 protective cushion layer 6 outer sheath 7 outer shield (outer shield layer) 8 inner sheath 9 inner shield (inner shield layer) 10 Holding tape 11 Signal core wire (transmission core wire) 12 Lead wire 13 Casing 14 Processing part 15 Drain wire 16 Interposition 17 Interposition string

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahiko Onishi 2-3-1 Iwata-cho, Higashi-Osaka City, Osaka Prefecture Tatsuta Electric Wire Co., Ltd. (72) Inventor Kihachi Onishi 2-3-3 Iwata-cho, Higashi-Osaka City, Osaka Prefecture No. 1 in Tatsuta Electric Wire Co., Ltd. (56) Reference JP-A-57-166526 (JP, A)

Claims (1)

[Claims] 1. A ground in which a coil 3 is suspended in the permanent magnet 2.
Install the seismic sensor 1 in the casing 4 with an air gap or a protective clip.
Seismic-electrical converter A , which is installed via the optional layer 5 ,
Data processing device that records and processes the signal from the coil
In a seismic detection device in which a signal transmission cable P is connected to B , a transmission core wire 11 of the signal transmission cable P is shielded 9 for each core or collectively, and an insulating layer 8 is further provided around it. shielding layer 7 is provided, the shield layer 9 of the inner Te, the one end thereof earthquake - electric transducer seismic sensor 1 a frame
And the other end of the data processing device.
The outer shield layer 7 is grounded through B, and one end thereof is grounded through the casing 4 of the seismic-electrical converter A , and the other end thereof is grounded through the casing 13 of the data processing device B. And a seismic detector protection device.