JP3375889B2 - Earthquake detection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in a governor room or the like in a gas supply system, and can easily and quickly perform adjustment work of calculation parameters and leveling work at the installation site during installation and maintenance of the device. The present invention relates to an earthquake detection device that can be performed.

[0002]

2. Description of the Related Art In a gas supply system, when an earthquake occurs, it is necessary to urgently cut off the supply of gas to prevent the damage from spreading due to gas leakage and the occurrence of secondary disasters. An earthquake detection device using is provided.

Such a conventional earthquake detecting device includes, for example, a so-called servo type acceleration sensor for detecting vibration,
An arithmetic processing circuit for arithmetically processing an SI value, which will be described later, based on a detection signal of the sensor, an arithmetic parameter / algorithm, a set value, etc. stored in advance in the memory means is housed in the explosion-proof case. In addition, a small bubble level for carrying out leveling work (adjustment of inclination) at the time of installing the apparatus is provided on the surface of the lid of the explosion-proof case. Since it is difficult to perform the adjustment work of the above-mentioned calculation parameters, algorithms, set values, etc. at the installation site of the device, it has been performed at the manufacturing factory of the device.

Further, the explosion-proof case is fixed to the floor of a governor room, which is an explosion-proof area, by means of fixing metal fittings and fixing bolts so that the inclination can be adjusted, and only such inclination adjustment is performed at the installation site. In addition, a so-called mechanical earthquake sensor or the like is also used in the device in order to ensure the reliability of the earthquake detection.

By the way, in such an earthquake detecting device, there has been proposed a means of using an SI (Spectrum Intensity) value as a measure of the intensity of earthquake motion in order to detect an earthquake having a high correlation with the degree of damage to a building.
It has been implemented. This SI value is generally represented by the following equation. Besides, an acceleration response SI value and a displacement response SI value can also be adopted.

[Chemical 1] Here, k is a coefficient, Sv is a velocity response spectrum, T is a period, and h is a damping coefficient of the building.

Such means is disclosed, for example, in JP-A-62-12.
No. 884, No. 62-12885, No. 62-12886, No. 6-214040, No. 8-36062.

In such means, the SI value is obtained by inputting the acceleration waveform of the seismic motion measured by the seismic sensor into the arithmetic unit that satisfies the equation of motion of the one-degree-of-freedom vibration system to obtain the speed response moment by moment. Is obtained by performing a predetermined calculation from the spectrum of the maximum value of, that is, the velocity response spectrum.

Next, the operation will be described. At the time of installation or maintenance of the device, the worker adjusts the tightening condition of the fixing bolts etc. based on the indication of the bubble level provided on the surface of the lid of the explosion-proof case, and then leveles the device. Such work is sequentially performed manually by the worker according to a complicated work process defined in the procedure manual. That is,
The work performed by the worker at the installation site of the device is only such a manual tilt adjustment, and the adjustment of the above-mentioned calculation parameters and the like, which is difficult to adjust, cannot be performed at the installation site, and therefore is performed at the factory.

When the servo type acceleration sensor of the device thus installed detects an earthquake, the above-mentioned SI is calculated based on the detection signal and the previously stored calculation parameters.
The value is calculated, and when it exceeds a predetermined threshold value, the output of the mechanical seismic sensor used in combination is also taken into consideration and the emergency shutoff instruction is output. As a result, the gas supply is cut off urgently, and the damage caused by the gas leak is prevented and the secondary disaster is prevented.

[0010]

Since the conventional seismic detection device is constructed as described above, the only parameter that can be adjusted at the installation site is the inclination of the device, and the level, the fixing bracket, the bolt, etc. are always available. There is a problem that the adjustment work requires a lot of trouble and the like.

Further, the earthquake detection device is often installed in a building without an air-conditioning facility, and mechanical and electrical changes over time may occur in the earthquake detection device due to temperature changes during the day and night or during summer and winter. There is a nature. Further, the building itself may be affected by ground subsidence or traffic vibration from the road, and the installation surface of the earthquake detection device may be tilted.

However, even if the seismic detection device itself or the installation location changes over time, various set values other than the inclination of the device cannot be adjusted at the installation site.

The present invention has been made to solve the above problems, and an object thereof is to obtain an earthquake detecting device capable of easily and quickly performing adjustment work of calculation parameters and leveling work at the installation site. To do.

[0014]

An earthquake detecting device according to a first aspect of the present invention has an input section, a display section, a memory section, a communication section, and a control section for controlling these, and is stored in the memory means. The setting value stored in the memory means and a connection terminal for connecting a portable setting device that changes the setting value via the communication unit .
It is provided with an adjusting means for adjusting the set value based on the gravitational acceleration .

[0015]

According to a second aspect of the present invention, an earthquake detecting device is provided with a first plane portion parallel to a plane including two detection axes of a semiconductor acceleration sensor in a part of a case.

According to a third aspect of the present invention, an earthquake detecting device is provided with a second flat surface portion, which is perpendicular to a flat surface including two detection axes of a semiconductor acceleration sensor, in a part of a case.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below. Embodiment 1. 1 is a block diagram showing a gas supply system using an earthquake detector according to Embodiment 1 of the present invention, FIG. 2 is a plan view showing the earthquake detector, FIG. 3 is a side view showing the earthquake detector, and FIG. 2 is a sectional view taken along the line AA, FIG. 5 is a sectional view taken along the line BB of FIG. 2, FIG. 6 is a plan view showing a state in which the cover of the earthquake detection device is removed, and FIG. 7 is a circuit configuration diagram of the earthquake detection device. 8 is a side view showing the tilt adjusting mechanism, and FIG. 9 is a circuit configuration diagram of the portable setting device.

First, a schematic configuration of a gas supply system using the present invention will be described. In FIG. 1, 1 is a gas manufacturing plant equipped with an explosion-proof zone, 2 is a gas tank, 3 is a high-pressure pipe, 4
And 7 are governors, 5 is a governor station equipped with an explosion-proof zone, 6 is a medium pressure conduit, 7a is an emergency shutoff valve, 8 is a monitoring room, 9
Reference numerals 10 and 10 designate an emergency shutoff instruction, 11 a governor room which is an explosion-proof area, and 12 a governor having an emergency shutoff function.

Reference numeral 20 denotes an explosion-proof case (case), which will be described later.
0 is a semiconductor acceleration sensor which will be described later capable of measuring three axes (X, Y, Z axes), 40 is an arithmetic processing circuit which will be described later, 57 is a digital signal (binary signal) output from the arithmetic processing circuit 40, and 60 is This is a control panel installed on the exterior wall of the governor (non-explosion proof area).

Reference numeral 61 is a mechanical seismic sensor installed in the control panel 60 and utilizing a pendulum, and 62 is a governor when both the digital signal 57 and the output signal of the mechanical seismic sensor 61 are output. A determination circuit that generates a shutoff signal 63 that shuts off 12, a low-pressure conduit 64, a gas-supplied household, 66 a gas-supplied factory, and 90 a portable setting device described later.

Next, the earthquake detector will be described in more detail. 2 to 6, 20 is an O-ring 21.
It is an explosion-proof case formed of a metal such as aluminum so as to satisfy a predetermined pressure resistance, having a cover 20a that can be opened and closed via a wire and a wire lead-out hole 20b formed in the wire lead-out portion 20c. The explosion-proof case 20 is manufactured so as to satisfy the explosion-proof structure standard of the electrical machinery (Ministry of Labor). That is, the length and number of threads of the explosion-proof case 20 and the cover 20a, the pressure-proof packing (described later) of the wire lead-out hole 20b, and the like satisfy the above-mentioned standards.

Further, 22a, 22b and 22c are flanges, 23 is a screw hole, 24 is a shield wire in which various wirings described later are put together, 25 is a pressure resistant packing made of, for example, butyl rubber, 26 is a compression bolt for compressing the pressure resistant packing 25,
A lock nut 27 fixes the compression bolt 26.

That is, the shield wire 24 is inserted into the wire lead-out hole 20b, and the pressure-proof packing 25, the compression bolt 26, and the lock nut 27 are provided so that the sealing and pressure-proof property of the portion can be secured. Is. The length of the pressure-resistant packing 25 after compression satisfies the above standard.

Reference numeral 30 is a semiconductor acceleration sensor. For example, it is possible to use the sensor and the signal processing circuit thereof that utilize the change in capacitance described in JP-A-9-43068. As mentioned in the section of the prior art of the publication,
A plurality of pairs of electrostatic capacitance elements are provided by mounting electrodes on the respective opposing surfaces of the fixed substrate and the flexible substrate, and an XY plane parallel to the substrate surface is set, and a Z-axis orthogonal to the XY plane is set. X, Y,
The change in acceleration in the Z-axis three-dimensional direction is detected for each X-, Y-, and Z-axis direction component based on the change in capacitance between a plurality of pairs of capacitance elements. The capacitance difference between the capacitance elements C21 and C23 (C21-C23) is the output for the acceleration in the X-axis direction, and the capacitance difference between the capacitance elements C22 and C24 is the output for the acceleration in the Y-axis direction. The capacitance difference (C22-C24) and the output with respect to the acceleration in the Z-axis direction can be detected as the capacitance C25 of the capacitance element C25 or C21 + C22 + C23 + C24.

The inclinations of the X-axis and the Y-axis are obtained by detecting an increase / decrease in capacitance due to a change in gravity, and the direction of the inclination is determined as positive or negative compared with the output in the normal state. Determined by things. Regarding the Z-axis, the capacitance increases or decreases due to vertical acceleration, so the direction of acceleration is known, but it is not related to the inclination.

The relationship between the output of each axis and the tilt amount is initially verified in advance at the factory, and the tilt amount of the apparatus can be easily obtained by recording this in the memory 44 or the like.

As the semiconductor acceleration sensor 30,
The acceleration sensor is not limited to the capacitance type acceleration sensor, and for example, a piezoresistive type or a piezoelectric type acceleration sensor can be used.

Reference numeral 31 is a support member, and 32 is a CPU.
A board, 33 is a power board, 34 is a terminal block, 35 is a guard, and 36 is a loader connection terminal (connection terminal) for connecting a portable setting device 90 described later to a loader interface 55 described later.

Next, the circuit configuration of the earthquake detection device is shown in FIG.
It will be described based on. In FIG. 7, 40 is the above-mentioned C
An arithmetic processing circuit formed on the PU board 32 or the like, 41 is a control unit, 42 is an SI value calculated by the SI value calculation unit 42a, a seismic intensity calculated by the seismic intensity calculation unit 42b, and an acceleration calculation unit 42c. Acceleration and
It is a calculation value selection unit that selects an arbitrary plurality of calculation values from the displacement amounts calculated by the displacement amount calculation unit 42d and the calculated values of the speed calculated by the speed calculation unit 42e. That is, the calculated value selection means 42 provides an optimum setting at the installation site by appropriately combining various calculation functions as needed.

Reference numeral 43 is a judging means for judging whether or not to output the emergency shutoff instruction based on the calculated value.

Reference numeral 44 is a ROM, PROM, RAM, EEP
A memory (memory means) composed of a ROM or the like, for example, various calculation programs to be processed by the CPU, calculation parameters, judgment threshold values required by the judgment means 43, adjustments at the factory, and vibrations. The output data of each axis when it is not present is recorded in advance.

The operation program, operation parameters, various set values, etc. recorded in the memory 44 can be rewritten by the portable setting device 90 described later.

The cutoff instruction is configured to be output to the outside via a relay interface 53 described later. For example, when the determination means 43 determines to cut off, an electromagnet inside the relay is excited by a relay drive circuit (not shown), and the normally open contact is closed to output to the outside.

Reference numeral 45 is a real-time clock, 46 is a sensor interface, 47 is a temperature sensor for correction, 48 is a reference voltage, 49 is a power supply circuit, 50 is a backup circuit, 5
Reference numeral 1 is a digital output interface, and 52 is a digital input interface.

Reference numeral 53 is a relay interface for outputting the calculation processing result as a relay contact output signal instead of a digital signal. The relay interface 53 is configured to be capable of directly connecting a circuit such as DC 24 V or AC 100 V, and thus can directly operate various loads such as an actuator, a valve, or a large relay. It is like this. The relay interface 53 and a contact side circuit (not shown) are electrically separated from each other. The relay interface 53 can be connected not only to the relay but also to a separate insulation type electric component such as a photo coupler or a photo MOS relay.

54 is an analog output interface, and 55
Is a loader interface for connecting a portable setting device 90 described later, which gives a setting signal for selecting the calculated value to the calculated value selection means 42, and includes the loader connection terminal 36 described above.

The wiring from the external power supply to the power supply circuit 49 and the wiring of each of the interfaces 51, 52, 53, 54 are drawn out of the explosion-proof case 20 by the shield wire 24 described above.

2 to 5, reference numeral 70 is formed on the upper surface of the wire lead-out portion 20c so as to be parallel to the XY plane including the two detection axes (X axis and Y axis) of the semiconductor acceleration sensor 30. It is a first plane portion and forms a horizontal plane when the explosion-proof case 20 is installed horizontally.
That is, a level 86 described later is provided on the first plane portion 70.
By mounting the device, the leveling work of the device can be easily performed.

On the other hand, reference numeral 72 is a second flat portion formed so as to be perpendicular to the XY plane so as to face each of the four side surfaces of the explosion-proof case 20, and when the explosion-proof case 20 is installed horizontally. To form a vertical surface.

The bottom of the explosion-proof case 20 is formed in a horizontal plane, and when the seismic detector is placed on a horizontal reference plane, the horizontality of the first plane section 70 and the second plane section 7 are set.
The verticality of 2 can be easily secured.

Next, a tilt adjusting mechanism used for mechanically adjusting the tilt of the earthquake detecting device at the installation site will be described with reference to FIG. In FIG. 8, 79 is the floor of the equipment installation site, 80 is the floor 79 and anchor bolts 81
The reference numeral 82 denotes a base plate fixed by means of welding, the reference numeral 82 denotes an adjustment bolt vertically installed on the base plate 80 by welding, and the reference numeral 83 denotes an adjustment plate for mounting and fixing the explosion-proof case 20. It is movably attached by. 85 is each flange 22 of the explosion-proof case 20
Is a fixing bolt for fixing to the adjusting plate 83, and 86 is a spirit level placed on the first plane portion 70.

Next, the portable setting device 90 will be described with reference to FIG. The portable setting device 90 is connected to the loader connection terminal 36 at the installation site of the earthquake detection device, and is for changing the calculation program, the calculation parameter, and various set values stored in the memory 44.

That is, specifically, the portable setting device 90
Has the following functions. (1) A setting signal for causing the calculated value selection means 42 to select a predetermined calculated value is transmitted. (2) When the output value of the earthquake detection device drifts due to a change in the inclination of the earthquake detection device due to changes in the installation environment (changes in the building, vibration due to traffic, etc.), the arithmetic processing circuit 40 and the semiconductor acceleration sensor. When 30 changes with time and the output value of the earthquake detector drifts, the output is changed to "PV
Value, and adjust its bias. (3) Further, the semiconductor acceleration sensor 30 is caused to generate a reference acceleration based on the gravity of the earth, and the output of the sensor is adjusted (hereinafter referred to as “span adjustment”) based on the reference acceleration. (4) Further, the arithmetic program recorded in the memory 44 is rewritten as necessary. (5) Calculation parameter. The k, T, h, etc. of the arithmetic expression can be changed. Of course, other seismic intensity and other calculation parameters can be changed. (6) It is possible to change various set values such as set values for digital output and relay output, and set values for error output of various abnormalities such as inclination abnormality and temperature abnormality.

In order to perform such a function, the portable setting device 9
0 is configured as follows. That is, in FIG. 9, reference numeral 91 denotes an input section formed by a keyboard or a so-called touch screen for an operator to input, and 92 indicates, for example, various calculation contents and work instruction contents to the worker. A display unit formed by a liquid crystal display device, a memory unit 93 for recording various data necessary for the operation of the portable setting device 90, and a predetermined communication unit 94 for performing predetermined communication via the loader interface 55 of the seismic detection apparatus main body. As described above, the communication unit performs conversion processing of various signals, and includes a communication cable and a connection terminal (not shown) for connecting to the loader connection terminal 36. A control unit 95 controls the input unit 91, the display unit 92, the memory unit 93, and the communication unit 94.

The portable setting device 90 can be constructed by applying the "EEPROM rewriting method for industrial measuring instruments" disclosed by the applicant of the present application in Japanese Patent No. 2523053.

Next, the operation of earthquake detection will be described. In FIGS. 7 and 1, when the semiconductor acceleration sensor 30 detects an earthquake, the detection signal indicates the sensor interface 46.
Is input to the control unit 41 via. In this case, since the semiconductor acceleration sensor 30 can measure three axes (X, Y, Z axes), more accurate vibration measurement of seismic motion can be performed. Particularly in a direct earthquake, since the Z-axis (vertical) direction vibrates first, more important measurement information can be obtained.

In the control unit 41, the SI value, seismic intensity, etc. selected in advance by the calculated value selecting means 42 are calculated by the respective calculation units 4
2a to 42e. The setting signal that causes the calculated value selection unit 42 to select a calculated value is set by the operator by connecting the portable setting device 90 to the loader connection terminal 36 at the installation site and communicating with the loader to set the optimum threshold value for the installation site. It can be set easily and quickly.

The determination means 43 determines whether or not to output the emergency cutoff instruction based on the calculated value. When the emergency cutoff instruction is output, for example, the determination circuit of the control panel 60 from the digital output interface 51. A digital signal 57 is output to 62.

Therefore, the shield wire 24 is connected to the governor chamber 1
Even if it is routed from 1 to the control panel 60, it will be more resistant to noise,
It will not malfunction. In this case, for example, a more reliable detection can be expected by configuring so that the cutoff instruction signal is output when both the SI value and the seismic intensity exceed a predetermined value.

Then, this digital signal 57 is input to the determination circuit 62 of the control panel 60, as shown in FIG.
On the other hand, the output of the mechanical earthquake sensor 61 is also input to the determination circuit 62.

In the decision circuit 62, these digital signals 5
When both 7 and the output signal of the mechanical seismic sensor 61 are output, it is judged as a logical product and a cutoff signal 63 is generated, whereby the governor 12 is cut off. That is, the supply of gas to the low-pressure conduit 64 is urgently shut off, and the damage caused by gas leakage and the secondary disaster can be effectively prevented.

In the decision circuit 62, when it is desired to output the shutoff signal 63 at an early stage in order to ensure safety during an earthquake, it is determined as the logical sum of the digital signal 57 and the output signal of the mechanical earthquake sensor 61. You can also let it.

Further, since the relay interface 53 outputs the calculation processing result as a relay contact output signal instead of a digital signal, if this is connected to a circuit such as DC 24 V or AC 100 V, an actuator, a valve, Various loads such as large relays can be operated directly. In this case, since the relay interface 53 and the contact side circuit (not shown) are electrically separated from each other, the noise characteristic is further improved as compared with the digital signal 57 output from the digital output interface 51.

Next, the adjustment work procedure (PV bias adjustment, gravity span adjustment) of the seismic detector using the portable setting device 90 will be described with reference to FIGS. 9 to 14. Here, FIG. 10 is a schematic view showing an example of an initial screen of the portable setting device, FIG. 11 is a flowchart showing an adjustment work procedure of the earthquake detection device, and FIG. 12 is an example of a PV bias screen of the portable setting device. FIG. 13 is a schematic view, FIG. 13 is a side view showing gravity span adjustment using a V block, and FIG. 14 is a schematic view showing an example of a span screen of a portable setting device.

First, when the worker connects the portable setting device 90 to the loader connection terminal 36 of the seismic detection device at the installation site and selects the "gravity adjustment procedure mode" (not shown), the display unit of the portable setting device 90 is displayed. At 92, an initial screen shown in FIG. 10 is displayed.

Then, in order to output the current PV value,
Select current value measurement 100 from this initial screen
When the T key 103 is pressed, the current value measurement in the current value measurement step (adjustment means) ST104 and the current PV value display in step ST105 are executed in the flowchart shown in FIG. 11, and the PV bias screen shown in FIG. 12 is displayed. .

Next, the operator judges the magnitude of the drift amount from the PV value, and the zero adjustment step (adjustment means) ST1.
At 07, the so-called zero adjustment of the seismic detection device is performed. That is, when the drift amount is small, the correction data is input from the input unit 91 of the portable setting device 90 until the PV value becomes zero or the allowable amount without using the mechanical tilt adjusting mechanisms 80 to 85 described above. By doing so, electrical zero point adjustment is performed. On the other hand, when the drift amount is large, the mechanical inclination adjusting mechanisms 80 to 85 described above are used together to adjust the inclination of the earthquake detecting device.

Each of the adjustment procedures will be described in more detail. When the amount of drift is small, mechanical zero point adjustment is not necessary, so the operator selects zero adjustment 101 in FIG. 10 in order to perform electrical zero point adjustment through step ST106 in FIG. When you press the ENT key 103,
Step ST107 of FIG. 11 is executed.

Then, when the PV bias value is input in step ST108 from the input unit 91 of the portable setting device 90 so that the PV value of each axis (X, Y, Z axes) becomes, for example, zero, the current value is calculated in step ST109. PV value display is executed and the new PV value is displayed as shown in FIG. As a result, the end of the desired zero point adjustment can be confirmed.

As described above, the zero point adjustment, which has been impossible at the conventional installation site, can be easily and quickly performed only by the electrical calculation process by the loader communication using the portable setting device 90.

On the other hand, when the amount of drift is large, mechanical zero point adjustment is also required, so step S in FIG.
When the operator selects the span adjustment 102 in FIG. 10 through T106 and presses the ENT key 103, the span adjustment step (adjustment means) ST110 in FIG. 11 is executed.

Then, the worker removes the earthquake detecting device from the installation place in step ST111, and first, in step ST112, adjusts the PV value in the Z-axis direction.

That is, since the bottom surface of the explosion-proof case 20 is formed in a horizontal plane as described above, when the earthquake detector is placed on a horizontal plane, the Z axis of the semiconductor acceleration sensor 30 coincides with the gravity direction of the earth, Accurate acceleration (-1 [G] =
-980 [Gal]) can be applied. This value is input from the input unit 91 by the portable setting device 90 and recorded in the memory unit 93. In step ST113 of FIG. 11, the Z axis is -1.
The PV value is set to zero [Gal] when [G] is applied.

Next, the seismic detector is turned over by 180 degrees, gravity (+1 [G] = + 980 [Gal]) is applied in the opposite direction, and the value is recorded in the same manner. Step ST114
Sets the PV value of the Z axis in this state to be +1960 [Gal].

As a result, the gravity span of 2 [G] can be adjusted for the Z axis. Since the gravity of the earth varies depending on its location, when the correction is necessary, the above-mentioned adjustment work will be performed with the correction value taken into consideration.

The Z axis is adjusted first because the semiconductor acceleration sensor 30 for the three axes depends on the sensitivity of another axis with respect to the Z axis, and it is desirable to adjust the Z axis first.

Also, for the X axis and the Y axis, the gravitational span adjustment is performed on the same principle as described above. At that time, as shown in FIG. 13, by mounting the earthquake detection device on the V block 119 in which a 90-degree V groove is formed so as to match the shape of the earthquake detection device, the X-axis and Y-axis directions are , The component of gravity (45 degree component) can be applied simultaneously and accurately.

As a result, steps ST115 to 118 are executed.
At -980 [Gal] in the X-axis and Y-axis directions.
To +980 [Gal] PV value. An example of the span screen displayed on the display unit 92 of the portable setting device 90 during the above span adjustment is shown in FIG.

After the span adjustment of each axis is completed as described above, in step ST120 of FIG. 11, the seismic detector is installed so that the Z axis is vertically downward, and step S
At T121, the PV value of each axis is displayed.

The leveling at the time of installation of this earthquake detecting device is performed by using the tilt adjusting mechanisms 80 to 85 shown in FIG. That is, the worker sets the level 86 to the first flat surface portion 7
Then, the tilt of the adjusting plate 83 is adjusted by vertically moving the adjusting nut 84 of the adjusting bolt 82 while watching the display of the level 86, and the leveling is performed.

If the PV bias adjustment shown in steps ST107 to 109 is performed after the installation of this earthquake detecting device, more accurate adjustment can be performed. In addition, the PV bias adjustment procedure and the gravity span adjustment procedure described above may be performed first, and if the detection accuracy required in the usage environment of the earthquake detection device can be ensured, the PV bias adjustment procedure and the gravity span adjustment procedure may not necessarily be performed.

As described above, according to the first embodiment, by connecting the portable setting device 90 to the loader connecting terminal 36 and communicating, various setting values and the like can be easily and quickly changed at the installation site. The effect is obtained.

Particularly in the case of initial adjustment of the apparatus, when the amount of drift is small, loader communication using the portable setting device 90 is performed without using the tilt adjusting mechanisms 80 to 85, which require complicated adjustment. The effect that the adjustment can be performed quickly can be obtained only by the electrical calculation processing by.

The wire lead-out portion 20c of the explosion-proof case 20
By providing the first flat surface portion 70 in the above, it is possible to easily secure a horizontal surface on which the level 86 is easily placed, and it is possible to obtain an effect that the leveling work can be performed easily and quickly.

Further, the explosion-proof case 20 has a second flat portion 7
Since 2 is provided, a predetermined gravity can be easily applied to the semiconductor acceleration sensor 30 by using a jig such as the V block 119, and the value can be used to easily and quickly calibrate the earthquake detection device at the installation site. Therefore, it is possible to provide a highly reliable earthquake detection device.

Further, by transmitting a predetermined setting signal to the calculated value selecting means 42 by the portable setting device 90, in addition to the SI value required by the gas industry, the seismic intensity required by the Japan Meteorological Agency and the construction industry are required. Since the displacement amount and speed to be calculated can be calculated arbitrarily, even if the number of product models increases or the product delivery destination, each threshold value, the measured amount, etc. need to be changed, it is possible to respond easily and flexibly. To be

Further, since the small semiconductor acceleration sensor 30 is used, the arithmetic processing circuit 40 can also be incorporated in the explosion-proof case 20, the size and weight of the entire apparatus can be reduced, and the handling can be facilitated.

Further, since the emergency cutoff instruction from the arithmetic processing circuit 40 is output as the digital signal 57, the reliability against noise is remarkably improved and the malfunction of the device can be effectively prevented.

Further, since the semiconductor acceleration sensor 30 can measure three axes (X, Y, Z axes), more accurate vibration measurement of seismic motion can be performed, and in particular, a direct type earthquake in which the Z axis (vertical) direction first vibrates. Then, the effect that more important measurement information can be obtained is obtained.

Further, for example, by configuring so as to output an alarm signal when both the SI value and the seismic intensity exceed a predetermined value, an effect that more reliable detection can be expected can be obtained.

In the first embodiment, during the adjustment work by the portable setting device 90, the operator is required to display the display unit 92.
Although a so-called interactive manual adjustment method of performing an input operation from the input unit 91 while confirming each step by seeing is adopted, the present invention is not limited to this, and a program previously recorded in the memory unit 93 or the like is used. It can also be done automatically.

Embodiment 2. In the second embodiment, the first flat surface portion and the second flat surface portion are provided on the flange of the explosion-proof case.

FIG. 15 is a plan view showing an earthquake detecting device according to Embodiment 2 of the present invention, and FIG. 16 is a side view showing the earthquake detecting device. In addition, the same reference numerals are given to the same or corresponding portions as those in the first embodiment, and the description will be omitted or simplified.

In FIGS. 15 and 16, reference numeral 70a denotes a first plane portion formed as a horizontal plane on the upper surfaces of the flanges 22a to 22c of the explosion-proof case 20, and is formed parallel to the XY plane described above. 72a is also the flange 22
The second flat surface portion is formed as a vertical surface on the side surface of a to 22c, and is formed perpendicular to the XY plane described above. The flanges 22a to 22c are arranged so as to form a central angle of 120 degrees with respect to the Z axis.

Therefore, according to this configuration, the level 86 is moved to the first plane portion 70 and the first flat portion 70 during the leveling operation.
It can be placed on both of the flat portions 70a. Other configurations and operation examples are the same as in the case of the above-described first embodiment, and therefore description thereof will be omitted.

As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained, and the flanges 22a to 22c of the explosion-proof case 20 are subjected to cutting work or the like, The effect that the 1st plane part 70a and the 2nd plane part 72a can be formed easily is acquired.

In the second embodiment described above, the flanges 22a to 22c are arranged so as to form a central angle of 120 degrees with respect to the Z axis, but the present invention is not limited to this, and the span of gravity is not limited to this. The angle may be an angle that facilitates work during adjustment.

Third Embodiment The third embodiment relates to an earthquake detecting device that is housed in a case that does not require explosion-proof specifications.

FIG. 17 is a perspective view showing an earthquake detecting device according to the third embodiment of the present invention. In the figure, reference numeral 123 denotes a rectangular parallelepiped case which is not explosion-proof, and is fixed to the case main body 123a by screws. It is composed of a lid 123b. The lid 123b and the bottom surface are formed as a first flat surface portion 70b which is a horizontal surface, and the four side surfaces of the case body 123a are formed as second flat surface portions 72b which are vertical surfaces.

Next, the operation will be described. Case 123
Is a rectangular parallelepiped, any one of the first plane portions 70b,
By arranging the second flat portion 72b on a horizontal plane, the vertical gravitational acceleration can always be applied easily and accurately, and the gravitational span adjustment described above becomes easy.

Further, it is possible to compare with an initial set value adjusted at the factory at the time of shipment of the apparatus, and by comparing the drift amount, it is possible to easily determine an abnormal state requiring calibration of the apparatus.

As described above, according to the third embodiment, the case 123 can be easily prepared, and by placing any one of the first plane portion 70b and the second plane portion 72b on the horizontal plane, The vertical gravitational acceleration can always be applied easily and accurately, the gravitational span adjustment can be facilitated, and it is possible to easily determine whether or not calibration is necessary. In addition, the level 86 can be easily placed, and the leveling operation can be easily performed.

In the third embodiment described above, the case 123 is formed as a rectangular parallelepiped, but the case 123 is not limited to this and may be a cube or another shape.

[0095]

As described above, according to the first aspect of the present invention, the set value stored in the memory means having the input section, the display section, the memory section, the communication section and the control section for controlling them can be set. The setting value stored in the memory means and the connection terminal for connecting the portable setting device to be changed through the communication unit
Since the adjustment means for adjusting based on the acceleration is provided, there is an effect that various setting values and the like can be easily and quickly changed at the installation site by connecting the portable setting device to the connection terminal for communication.

Particularly in the case of initial adjustment of the apparatus, when the amount of drift is small, it is not necessary to use a tilt adjusting mechanism that requires a lot of adjustment, and an electrical adjustment is made by communication using a portable setting device. There is an effect that the adjustment can be quickly performed only by the arithmetic processing. Also,
Electrical acceleration of predetermined gravitational acceleration to a semiconductor acceleration sensor
It can be applied accurately and accurately.
Regular work can be performed easily and quickly at the installation site.
There is an effect.

[0097]

According to the second aspect of the present invention, since the first plane portion parallel to the plane including the two detection axes of the semiconductor acceleration sensor is provided in a part of the case, it is easy to mount the spirit level. There is an effect that a horizontal surface can be easily secured and leveling work can be performed easily and quickly.

According to the third aspect of the invention, since the second plane portion perpendicular to the plane including the two detection axes of the semiconductor acceleration sensor is provided in a part of the case, a jig such as a V block is provided. When used together, a predetermined acceleration of gravity can be applied to the semiconductor acceleration sensor easily and accurately, and the value can be used to easily and quickly calibrate the seismic detection device at the installation site, thus providing a highly reliable earthquake. There is an effect that a detection device can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a gas supply system using an earthquake detection device according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an earthquake detection device.

FIG. 3 is a side view showing an earthquake detection device.

4 is a cross-sectional view taken along the line AA of FIG.

5 is a sectional view taken along line BB in FIG.

FIG. 6 is a plan view showing a state where the cover of the earthquake detection device is removed.

FIG. 7 is a circuit configuration diagram of the earthquake detection device.

FIG. 8 is a side view showing a tilt adjusting mechanism.

FIG. 9 is a circuit configuration diagram of a portable setting device.

FIG. 10 is a schematic diagram showing an example of an initial screen of a portable setting device.

FIG. 11 is a flowchart showing an adjustment work procedure of the earthquake detection device.

FIG. 12 is a schematic diagram showing an example of a PV bias screen of a portable setting device.

FIG. 13 is a side view showing gravity span adjustment using a V block.

FIG. 14 is a schematic diagram showing an example of a span screen of a portable setting device.

FIG. 15 is a plan view showing an earthquake detection device according to a second embodiment of the present invention.

FIG. 16 is a side view showing the earthquake detection device.

FIG. 17 is a perspective view showing an earthquake detection device according to a third embodiment of the present invention.

[Explanation of symbols]

20 Explosion-proof case (case) 30 Semiconductor acceleration sensor 36 Loader connection terminal (connection terminal) 40 arithmetic processing circuit 44 memory (memory means) 57 digital signals (binary signals) 70, 70a, 70b 1st plane part 72, 72a, 72b Second flat surface portion 90 Portable setting device 91 Input section 92 Display 93 Memory section 94 Communications Department 95 control unit ST104 Current value measurement step (adjustment means) ST107 Zero adjustment step (adjustment means) ST110 Span adjustment step (adjustment means) 123 cases

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takehiro Kanamori 2-12-19 Shibuya, Shibuya-ku, Tokyo Yamatake Honeywell Co., Ltd. (72) Inventor Shunji Ichida 2-12-19 Shibuya, Shibuya-ku, Tokyo Yamatake Honeywell Co., Ltd. (72) Inventor Takayuki Akimoto 2-12-19 Shibuya, Shibuya-ku, Tokyo Yamatake Honeywell Co., Ltd. (72) Inventor Yoshihisa Shimizu 2-26-3, Kohinata, Satte City, Saitama Prefecture (72) Inventor Kenichi Koganemaru 5-16-5 Sakuradai, Nerima-ku, Tokyo (56) References JP-A-8-77475 (JP, A) JP-A-8-304555 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01V 1/16

Claims (3)

(57) [Claims] 1. A semiconductor acceleration sensor for detecting acceleration in three axial directions, and arithmetic processing based on a detection signal of the semiconductor acceleration sensor and a set value stored in a memory means, and the arithmetic processing result is a binary signal. In an earthquake detection device including an arithmetic processing circuit capable of outputting as a signal and a case accommodating the semiconductor acceleration sensor and the arithmetic processing circuit, an input unit, a display unit, a memory unit, a communication unit, and a control unit for controlling these And a connection terminal for connecting a portable setting device that changes the set value stored in the memory means via the communication unit, and the set value stored in the memory means is accelerated by gravity.
An earthquake detecting device comprising an adjusting means for adjusting based on a degree . 2. The earthquake detecting device according to claim 1, wherein a first plane portion parallel to a plane including two detection axes of the semiconductor acceleration sensor is provided in a part of the case. 3. A semiconductor acceleration two detection axes earthquake detecting apparatus according to claim 1 or claim 2, wherein in that a plane and second plane portions perpendicular to the portion of the case including the sensor.