JPH0248871B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a seismometer that displays the magnitude of vibrations caused by earthquakes and strong winds in various buildings, and is particularly applicable to control and operation of various facilities such as elevators. Regarding suitable seismometers.

[Background of the invention]

Elevators, various railways, large-capacity power plants,
Alternatively, if strong vibrations due to an earthquake or the like are applied to various plant equipment during operation, there is a risk that an abnormality will occur in the facility, leading to a dangerous situation.

Therefore, in these various facilities, when vibrations due to an earthquake appear in a specific location such as the building, structure, or site where they are installed, the operational status of those facilities is changed to prevent abnormalities caused by the vibration. It is desirable to perform control that quickly brings the vehicle into an operating state that does not lead to a dangerous situation. Note that such an operating state is called controlled operation, and the control for this is called controlled operation control.

For example, in an elevator, if the building in which it is installed shakes due to an earthquake or strong wind, causing an abnormality in its running function, the elevator car may stop at a location other than the floor stopping position, causing passengers and others to be injured. Therefore, in order to prevent such a situation from occurring and to return the elevator to normal operation as soon as possible, it is extremely useful to provide a controlled operation function. For this reason, the control operation control system has come to be applied to many elevators.

Incidentally, for such air traffic control, an earthquake detection means that detects vibrations caused by an earthquake or the like and generates an appropriate air traffic control signal is required.

Therefore, to explain the earthquake detection method that has been used in the past, as an index expressing the influence of earthquake motion, as is well known, there is the Japan Meteorological Agency's seismic intensity scale shown in Figure 2, and from now on, the medium earthquake (seismic intensity ) or a strong earthquake (seismic intensity), it is possible to generate a control signal.

However, the actual determination of the seismic intensity based on this seismic intensity class has conventionally been based on the judgment of the situation based on the observer's experience, and this is not suitable for air traffic control.

Therefore, conventional methods have been used to obtain control signals by using acceleration detectors as seismometers and by correlating the acceleration of vibrations caused by earthquakes with seismic intensity classes.This acceleration is shown in the rightmost column of Figure 2. For example, damage to buildings due to earthquake motion begins at the seismic intensity, but the corresponding acceleration is in the range of 80 to 250 gal. Suppose there is.

Figure 3 shows a typical example of a seismometer using such an acceleration detection method. 1x and 1y are acceleration sensors, 1x detects acceleration ax in a certain direction, for example, the x direction, and 1y detects the acceleration ax in the x direction. 2x, 2y are amplifiers,
3 is a vector adder for adding signals Ax and Ay proportional to the accelerations ax and ay in the orthogonal directions to obtain the absolute value A of the acceleration in any direction;
4 is a comparator for generating a control signal Y by comparing the absolute value A of acceleration with a predetermined setting value; 5 is an output terminal; and 6 is a display for displaying the absolute value A.

By the way, as seismometers using this acceleration detection method have become widespread, various problems have arisen, and the idea of corresponding acceleration to seismic intensity has been questioned.

This will be explained with reference to FIGS. 4 and 5.

Figure 4 shows the acceleration and damage observed in earthquakes that occurred in the past.For example, in the Matsushiro earthquake swarm, an acceleration of 450 cal was observed, which is equivalent to the Suzeba seismic intensity from Figure 2. However, there was almost no damage.On the other hand, in the Niigata earthquake, the acceleration was 120 gal, and from the perspective of acceleration response, it would only have a seismic intensity as shown in Figure 2, but the damage caused was the collapse of a building.

There have been several reports on contradictory results due to acceleration response, one of which is a paper by Mr. Takagi (Meteorological Research Institute Report, Vol. 20,
No. 1, P79-89, 1972).

Figure 5 shows the relationship between the actual seismic intensity and acceleration compiled by Mr. Takagi.The solid line is the relationship between the seismic intensity and its equivalent acceleration in Figure 2, and the black dots are based on the judgment of the observer. These are the results of measuring the seismic intensity and the acceleration at that time.As is clear from the results, there is not much correlation between the seismic intensity and the equivalent acceleration.

Therefore, in the conventional acceleration detection seismometer,
The seismic intensity could not be detected correctly, and as a result,
Elevators, etc., may not be able to properly control the operation of elevators, and elevators may be stopped in response to weak earthquakes that do not require controlled operation, or on the other hand, elevators may be operated without responding to strong earthquakes. The problem was that it allowed the system to continue as it was, creating the risk of a major accident.

On the other hand, the paper by Mr. Takagi mentioned above examines the physical quantities related to earthquakes that have a strong correlation with seismic intensity, and according to this, the maximum value of seismic wave energy at a point is related to seismic intensity. It has been reported that this is the one that shows the strongest correlation. In other words, if the seismic wave energy passing through a certain point is E[J], then E=KR ² √Σ(D ² /T)...(1) where, K: proportionality constant R: distance from the epicenter to that point Distance ρ: Density of the ground at that point μ: Rigidity modulus of the ground at that point D: Maximum amplitude of vibration displacement T: Period of vibration Therefore, in equation (1), KR ² √ means that the point is Since it can be regarded as a constant if it is determined, the maximum value of E will be proportional to D ² /T. Therefore, this D ² /T is called the wave energy coefficient.

Now, if we calculate both D ² /T and seismic intensity for an actual earthquake, and show the relationship between them, the sixth
It will look like the black dot in the figure.

Therefore, from this relationship, if the relationship between the seismic intensity and the wave energy coefficient D ² /T is determined as shown by the solid line in Figure 6, it is found that the two show an extremely good agreement. If vibrations caused by earthquakes are measured using a seismograph that detects ² /T and displays the seismic intensity, it will be possible to express the seismic intensity that fully matches the human experience, which can be used to control the operation of elevators, etc. It can be done in a form close to the ideal.

However, this wave energy coefficient D ² /
Attempting to measure T as it is would be extremely large-scale and time-consuming, which is why seismographs of this type have not yet been put into practical use.

[Purpose of the invention]

The present invention was made in view of the above-mentioned circumstances, and its purpose is to provide a seismometer that can easily determine the wave energy coefficient with a simple configuration and thereby accurately display the seismic intensity. is to provide.

[Summary of the invention]

In order to achieve this object, the present invention is characterized in that the velocity of vibrations caused by earthquakes or the like is detected, and the wave energy coefficient can be determined starting from this.

[Embodiments of the invention]

Hereinafter, the seismometer according to the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 shows an embodiment of the present invention, in which 2
1 is a speed detector installed at the location to be measured and used to detect the velocity v of vibration appearing there; 22
is an integrator for integrating the output v of the detector 21 to obtain the displacement d; 23 is a multiplier for multiplying the velocity v and the displacement d to obtain the product e of the two; and 24 displays the value of the product e. or display the seismic intensity determined from the relationship shown in Figure 6 after making the product e correspond to the wave energy coefficient D ² /T; 25 is a predetermined setting for the product e; This is a comparator for generating a control signal at the output terminals 26 to 29 by comparing the value with the control signal. Here, the output terminal 26 of the comparator 25
~29 are for outputting control signals with different set levels.For example, terminal 26 generates a signal when the product e exceeds 2 [kin-cm], and terminal 27 outputs a signal with a different set level. The system generates a signal when it exceeds [kin-cm].

Next, the reason why the above-mentioned wave energy coefficient D ² /T is determined by the embodiment shown in FIG. 1 will be explained. In addition, in FIG. 1, the vibration velocity v is directly determined by the velocity detector 21, but it is also possible to detect the acceleration a using an acceleration detector and integrate it to obtain the velocity v. Therefore, in the following explanation, the explanation will start from the acceleration a.

First, if acceleration a is expressed as a=A sin2πft...(2) where A: amplitude of vibration acceleration f: frequency (1/T) t: time, then velocity v is as follows. .

v=∫a dt =A/2πfcos(2πft+π) =V cos(2πft+π)...(3) here, V=A/2πf...(4) , and this V is the amplitude of the vibration velocity.

Next, if d is the displacement of vibration, d=∫v dt = A/(2πf) ² sin(2πft+π) = D・sin(2πft+π)...(5) Here, D=A/(2πf) ² = V/2πf = V·T/2π (5), which is the maximum amplitude of displacement in equation (1).

Now, if the product of velocity v and displacement d is e, then e=d・v =V・D cos(2πft+π)・sin(2πft+π) =V・D/2sin(4πft+2π) =V・D/2sin4πft =e _n・sin4πft ...(7) Here, e _n is the amplitude of e, e _n =V・D/2 = π(D ² /T) ...(8), and e _n wave energy coefficient D ² /T's π It will be doubled. That is, when a certain point vibrates due to an earthquake or the like, the amplitude e _n of the product e of the vibration velocity v and the vibration displacement d is proportional to the wave energy coefficient.

Therefore, as shown in FIG.
If the vibration displacement D is calculated by integrating it, and the product e of these v and d is obtained by the multiplier 23, the value of this product e will be proportional to the wave energy coefficient D ² /T, and therefore, By displaying this product e on the display 24, it is possible to display a seismic intensity that fully matches the seismic intensity experienced at that point, and the output terminals 26 to
If the controlled operation of elevators and the like is controlled based on the signals obtained at 29, accurate controlled operation can be obtained at all times.

According to this embodiment, the wave energy coefficient D ² /T can be easily determined by simply installing a sensor that detects the velocity or acceleration of vibration at a point where vibrations caused by an earthquake or the like are to be detected, and processing the output signal. ,
Moreover, it can be determined accurately.

By the way, in general, sensors that detect vibration velocity or vibration acceleration only detect vibrations in one characteristic direction. Therefore, in the embodiment shown in FIG. 1, the wave energy coefficient that can be detected thereby is D ² /T is also limited to one direction.

Therefore, another embodiment of the present invention is shown in FIG. 7, which operates effectively against vibrations appearing in any direction within the horizontal plane. In the figure, 21x,
21y is a vibration velocity detector which detects the vibration velocity vx in the x direction and the vibration velocity vy in the y direction, with the detection directions thereof being arranged at right angles to each other; 22
x, 22y are integrated with the velocities vx, vy, respectively, and x
An integrator to obtain the displacement dx in the direction and the displacement dy in the y direction, 23x and 23y are the velocity vx and displacement in the x direction
A multiplier for calculating the product ex of dx or the product ey of velocity vy and displacement dy in the y direction, respectively; 30 is the product ex and ey
This is an adder for calculating e by the sum of , and the rest is the same as the embodiment shown in FIG. In this embodiment as well, the vibration speed detectors 21x and 1y are not limited to those that directly detect the vibration speed, but may also be those that detect the vibration speed using a vibration acceleration detector and an integrator. Needless to say.

The reason why the wave energy coefficient in any direction within the horizontal plane can be obtained according to the embodiment shown in FIG. 7 will be explained.

First, since e=ex+ey...(9), these amplitudes are respectively e _n , ex _n , ey _n
Then, e _n = ex _n + ey _n = π (Dx ² /T) + π (Dy ² /T) = π / T (Dx ² + Dy ² ) = πD ² /T Here, Dx: displacement in the x direction Amplitude Dy: Amplitude of displacement in the y direction D: Amplitude of displacement in any direction within the horizontal plane Therefore, by simply finding the products ex and ey in the x and y directions and taking out their sum with the adder 30, The wave energy coefficient in any direction can be found.

Figure 8 shows 3 in which the vertical direction is also added to the horizontal plane.
This is an embodiment of the present invention in which the wave energy coefficient in an arbitrary direction within a dimension is determined.
21z is a vibration velocity detector for detecting the vibration velocity vz in the z direction, which is perpendicular to the x and y directions, and 22z is an integral for integrating the velocity vz to give the vibration displacement dz in the z direction. vessel, 23z
is a multiplier for determining the product ez of velocity vz and displacement dz, and the rest is the same as the embodiment shown in FIG.

According to the embodiment shown in FIG. 8, the reason why the wave energy coefficient in any direction in three-dimensional space is determined is as follows.

The amplitudes of ex, ey, ez, and e are ex _n , ey _n ,
ez _n , e _n , e _n = ex _n + ey _n + ez _n = π(Dx ² /T) + π(Dy ² /T) + π(Dz ² /T) = π/T(Dx ² +Dy ² +Dz ² ) = πD ² /T ...(11) Here, Dz is the displacement amplitude in the z direction, and therefore, the adder 30 calculates the
It can be seen that the wave energy coefficient in any direction in three-dimensional space can be obtained by simply adding the directional products ex _n , ey _n , and ez _n .

〔Effect of the invention〕

As explained above, according to the present invention, with a simple configuration that uses a vibration velocity detector or a vibration acceleration detector and processes the detection signal, it is possible to detect vibrations of buildings caused by earthquakes, strong winds, etc. Since it is possible to display the seismic intensity as a seismic intensity that closely matches the human experience, it is possible to eliminate the shortcomings of conventional technology and always accurately detect the seismic intensity and control the operation of elevators etc. reliably and with sufficient satisfaction. It is possible to easily provide a seismometer that can be used under various conditions.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of a seismometer according to the present invention, Fig. 2 is an explanatory diagram of seismic intensity classes and equivalent acceleration, Fig. 3 is a block diagram showing an example of a conventional seismometer, Figs. Fig. 5 is an explanatory diagram showing the problems of the acceleration detection method, Fig. 6 is an explanatory diagram showing the relationship between the wave energy coefficient and seismic intensity, and Figs. 7 and 8 are each another embodiment of the present invention. FIG. 21, 21x, 21y, 21z... Vibration speed detector, 22, 22x, 22y, 22z... Integrator, 23, 23x, 23y, 23z... Multiplier,
24...Display device, 25...Comparator, 26-29...
...Control signal output terminal, 30...Adder.

Claims (1)

[Scope of Claims] 1. A seismometer that detects vibrations appearing in a specific location and displays the seismic intensity, comprising a detection means for respectively providing the velocity and displacement of the vibrations, and the velocity and displacement detected by the means. 1. A seismometer comprising: a calculation means for calculating the product of displacement; and a seismic intensity display based on the output of the calculation means. 2. In claim 1, the detection means is means for detecting the velocity and displacement of the vibration as at least two components in directions perpendicular to each other, and the calculation means is a means for detecting the velocity and displacement of the vibration as at least two components in directions perpendicular to each other. A seismometer characterized in that it is a means for calculating and adding the products of velocity and displacement for each component. 3 In claim 1 or 2,
A seismometer characterized in that the output of the calculation means is configured to be a wave energy coefficient, which is a physical quantity corresponding to the amplitude of the wave energy of the vibration. 4. In any one of claims 1 to 3, the seismometer is a seismometer for air traffic control operation, and the output of the calculation means is compared with a predetermined value set in advance. A seismometer configured to generate a control signal.