JP2981511B2 - Seismic sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of the Invention> The present invention is, for example, attached to a printed circuit board for a gas meter or other gas appliances, and automatically detects a vibration such as an earthquake that exceeds a predetermined value. The present invention relates to a seismic sensor that achieves a disaster prevention function such as cutting and automatic digestion of a combustion device.

<Prior art and its problems> Examples of this type of seismic sensor are disclosed in Japanese Utility Model Laid-Open Nos. 55-21510, 55-114943, and 55-119938. A spherical type in which a sphere such as a steel ball is placed on a spherical or tapered tray and the switch is opened and closed by rolling of the sphere due to vibration, for example, Japanese Utility Model Publication No. 55-28938 As disclosed in Japanese Unexamined Patent Publication (Kokai) No. 57-74625 and the like, a pendulum weight is suspended in a case, and horizontal movement of the pendulum weight or a movable body integrally connected thereto is controlled. There is a pendulum type configured to detect.

In the case of the former spherical-type seismic sensor, a saucer constituting the rolling surface of the spherical object is required, so that the entire seismic sensor tends to be large in the horizontal direction.

On the other hand, the latter pendulum type seismic sensor is easier to reduce in size in the horizontal direction than the above-mentioned spherical type, but it requires a longer pendulum suspension distance to improve sensitivity. , The overall length of the seismic sensor in the vertical direction increases, making it difficult to reduce the size. Also, in the case of the conventional pendulum type seismic sensor, when the case is installed at an angle, the seismic part is affected by the inclination, and the relative inclination between the case and the seismic part at the time of installation is sensed. There are still many problems in terms of the reliability of operation as a seismic sensor.

<Object of the Invention> The present invention has been made in order to solve the above-mentioned conventional problems, and it is possible to reduce the size as a whole and to appropriately perform a predetermined seismic operation even when the mounting posture of the case is inclined. The aim is to provide a high-sensitivity seismic sensor that can perform the function.

<Structure and Effect of the Invention> A seismic sensor according to the present invention is provided with an automatic horizontal mechanism having a first pendulum weight suspended in a case and capable of pendulum movement, A seismic sensor having a second pendulum weight suspended coaxially and movably on a pendulum, and a double pendulum weight set between the automatic horizontal mechanism and the seismic sensor. It is characterized by comprising a switch mechanism that contacts and separates by a relative displacement of the weight in the horizontal direction, and a damper part that gives a vibration damping action to the automatic horizontal mechanism part.

In the above configuration, since the first and second pendulum weights are suspended coaxially, there is no relative displacement of the two pendulum weights in the horizontal direction, and the switch mechanism is kept open. Therefore, as long as no vibration exceeding a certain level such as an earthquake is applied, there is no relative displacement of the pendulum weights in the horizontal direction even if the case is installed with the case inclined. There is no fear.

In addition, since the above-mentioned automatic horizontal mechanism and seismic sensing mechanism have different configurations, each of these mechanisms can be determined individually, and there are few restrictions on the shape of parts. Can be planned.

Next, when vibration exceeding a certain level such as an earthquake is applied, the weights of the two pendulums try to move in a pendulum. However, since the damper part has a damping action on the automatic horizontal mechanism, the second Only the pendulum weight of the first pendulum moves in a seismic manner and is relatively displaced in the horizontal direction with respect to the first pendulum weight, thereby closing the switch mechanism.

Thus, the switch mechanism can be closed and a seismic operation can be performed with a slight relative displacement of the first and second pendulum weights in the horizontal direction, so that the length of the pendulum weight can be reduced even though the pendulum method is used. The size in the horizontal and vertical directions can be shortened without taking too large a size, and the overall size can be reduced from this point as well.

As described above, according to the present invention, it is possible to provide a seismic device having a smaller size and higher seismic performance than any of the above-described conventional devices.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing the structure of a seismic device according to an embodiment of the present invention. The seismic device is roughly divided into a cylindrical case A and a pendulum that can be installed in the case A and move in a pendulum. Horizontal mechanism B having a first pendulum weight 2 suspended on the
And a second hanging down coaxially with the automatic horizontal mechanism B and installed in the case A and suspended so as to be capable of pendulum movement.
Relative displacement of the two pendulum weights 2 and 3 in the horizontal direction, which is set between the automatic horizontal mechanism B and the seismic mechanism C having the pendulum weight 3 of FIG. And a damper section E for imparting a vibration damping action to the automatic horizontal mechanism section B.

The case A includes a case body 4 that opens upward,
A pair of fixed terminals 6 and 7 are provided upright at positions facing each other in the radial direction of the case main body 4. The case 4 is projected outward and the upper end is extended inside the case cover 5.

A beam member 8 that crosses the case body 4 in the radial direction is installed in the opening of the case body 4, and the beam member 8 is formed, for example, in a disk shape, and has a shaft hole in the center thereof.
8a is formed. An annular protrusion protruding upward is formed around the shaft hole 8a, and constitutes a bearing portion 8b described later. The beam member 8 may have a flat bar shape.

The pendulum weight 3 is suspended at the lower end of a suspension shaft 9 inserted through the center thereof, and a suspension portion 10 having a semi-spherical inner and outer surface is formed at the upper end of the suspension shaft 9. 10 convex spherical parts
10a is slidably supported by the bearing 8b. Thus, the pendulum weight 3 is swingably hung from the beam member 8 at the lower end of the suspension shaft 9 inserted in the shaft hole 8a.

The bearing part 8b, the suspension part 10, the suspension shaft 9, and the second pendulum weight 3 constitute a seismic mechanism C capable of pendulum movement.

A fulcrum member 11a projecting downward is slidably mounted on the concave spherical portion 10b of the hanging portion 10. The fulcrum member 11 protrudes from the center of the lower surface of the disc-shaped movable member 11, and the second As shown in the figure, locking claws 12a, 12a projecting outward in the radial direction are provided at the lower ends of a pair of hanging pieces 12, 12 extending downward from radially opposed portions of the movable member 11. The pair of hanging pieces 12, 12 are formed integrally with the through-holes 8 c, 8 c formed in the beam member 8 and the first pendulum weight 2, respectively.
And by inserting the locking claws 12a, 12a on the lower surface of the first pendulum weight 2 by inserting the locking claws 12a, 12a below the first pendulum weight 2 from the central shaft hole 2a. A jiro bay type swingable automatic horizontal mechanism B for automatically holding the seismic sensor horizontally is constituted.

The switch mechanism D for converting the pendulum motion of the second pendulum weight 3 into an electric signal includes an annular first conductive member 13 fitted in the central shaft hole 2a of the first pendulum weight 2, And a second cylindrical conductive member 14 fitted to the suspension shaft 9 of the second pendulum weight 3, and the second conductive member 14 is a first conductive member 13.
Is arranged opposite to the through hole 13a formed at the center of the main body at a predetermined interval over the entire circumference thereof, and this opposing portion constitutes a contact portion.

The movable terminal 13b, which is formed integrally with the first conductive member 13 and is bent upward, stands up through a through hole 8d formed in the beam member 8, and has a second terminal. The movable terminal 15 which is fixed to the conductive member 14 and is bent upright is formed with a through hole 8 e formed in the beam member 8.
And project upward. These movable terminals 13b, 15
Is a pair of external fixed terminals 6 fixed to the case body 4,
7 is disposed opposite to the upper end of the coiled lead wire 1 between the opposed terminals 6, 13b and between 15, 7 respectively.
6, 17 are interposed and electrically connected to each other.

The viscous liquid damper part E is connected to the case cover 5.
And a ring-shaped liquid-tight member 26 fitted into the case cover 5, a flexible thin film 27 such as rubber having a thick portion 27a having a substantially circular cross section around the periphery thereof, an oil filled in the gap, etc. Of the viscous liquid 28. Specifically, the first
As shown in the figure, the outer peripheral thick portion 27a of the flexible thin film 27 disposed on the inner surface of the case cover 5 is sandwiched between the inner surface of the case cover 5 and the liquid-tight member 26 to be fixed in a liquid-tight manner. A gap between the cover 5 and the flexible thin film 27
29 is formed, a viscous liquid 28 is filled into the space 29 from the hole 5b provided in the case cover 5, and the hole 5b is sealed by, for example, an ultraviolet-curable adhesive 30 to form a predetermined liquid. Of the viscous liquid type damper portion E of FIG.

At the center of the inner surface of the case cover 5, a projection 31 is provided so as to provide resistance to the flow of the enclosed viscous liquid 28 and enhance the damper mechanism.

The flexible thin film in the viscous liquid damper part E
27, the upper surface of the disk-shaped movable member 11 in the automatic horizontal mechanism B is brought into contact with the lower surface of the automatic horizontal mechanism B.
, And is configured to maintain the same seismic characteristics when the case A is mounted horizontally and when the case A is mounted at an angle.

 Next, the operation of the above configuration will be described.

In a state where the case A is horizontally mounted on a printed board for gas meter or the like so that the center line a of the suspension shaft 9 of the pendulum weight 3 is vertical, the first and second conductive members 13 of the switch mechanism D are provided. , 14 are separated and open.

In such a mounting state, when vibration exceeding a set value such as an earthquake is applied, as shown in FIG. 3, the second pendulum weight 3 moves between the hanging portion 10 at the upper end of the hanging shaft 9 and the bearing portion 8b. With the support point as a fulcrum, a pendulum motion is made around the support point, and the second conductive member 14 comes into contact with the first conductive member 13 to switch on.

Thereby, the space between the pair of external fixed terminals 6 and 7 facing each other is the coiled lead wire 16, the movable terminal 13 b, the first conductive member 13, and the second
Is electrically conducted through the conductive member 14, the movable terminal 15 and the coil-shaped lead wire 17 to perform a predetermined seismic operation.

Further, when the case A is attached at an angle, the automatic horizontal mechanism B uses the support point between the concave spherical portion 10b of the hanging portion 10 and the fulcrum member 11a as a fulcrum, and the first point around it.
, And is automatically held horizontally by the pendulum weight 2. That is, the center line b of the automatic horizontal mechanism B is the case A
It becomes vertical even in the inclined state. At this time, the upper surface of the disk-shaped movable member 11 of the automatic horizontal mechanism B is placed on the viscous liquid
The automatic horizontal mechanism B can be prevented from inadvertently vibrating because it is in contact with the lower surface of the flexible thin film 27. On the other hand, the second pendulum weight 3 can rotate around the support point between the suspension portion 10 at the upper end of the suspension shaft 9 and the bearing portion 8b as a fulcrum, as described above. 9 can coincide with the vertical center line b of the automatic horizontal mechanism B described above.

Therefore, in such an inclined mounting state,
When vibration exceeding a set value such as an earthquake is applied, a seismic operation similar to that in the above-described horizontal mounting state can be achieved.

As is apparent from the above, in the above configuration, the first and second pendulum weights 2, 3 are coaxially hung,
There is no relative displacement of the pendulum weights 2 and 3 in the horizontal direction, and the switch mechanism D is kept open. Therefore, as long as no vibration exceeding a certain level, such as an earthquake, is applied, even if the case A is installed at an angle, there is no relative displacement of the pendulum weights 2 and 3 in the horizontal direction.
Since the switch mechanism D is kept open, there is no possibility of malfunction.

In addition, since the automatic horizontal mechanism B and the vibration sensing mechanism C have different configurations, each of these functions can be determined individually, and there are few restrictions on the shape of the parts. Can be achieved.

Next, when vibration exceeding a certain level such as an earthquake is applied, both the pendulum weights 2 and 3 try to move in a pendulum, but the damper part E acts on the automatic horizontal mechanism part B to suppress the vibration. Therefore, only the second pendulum weight 3 moves in a seismic manner and is relatively displaced in the horizontal direction with respect to the first pendulum weight 2, thereby closing the switch mechanism D.

As a result, the switch mechanism D can be closed by a slight relative displacement of the first and second pendulum weights 2 and 3 in the horizontal direction and the seismic operation can be performed. The horizontal and vertical dimensions can be reduced without taking the lengths of the weights 2 and 3 too large.
From this point as well, the overall size can be reduced.

In the above embodiment, when a coaxial coil spring 28 is interposed between the first and second pendulum weights 2, 3, the second pendulum weight relative to the first pendulum weight 2 is provided. 3
, Ie, the natural vibration period, can be easily changed, thereby easily adjusting the sensitivity of the seismic sensor.

As the damper portion E in the present invention, the viscous liquid type shown in the above embodiment is optimal, but the same effect can be obtained by using an eter damper.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the structure of a seismic sensor according to one embodiment of the present invention, FIG. 2 is a sectional view taken along the line XX of FIG. 1, and FIG. It is a longitudinal cross-sectional view of the principal part of FIG. A: Case, B: Automatic horizontal mechanism, C: Vibration sensing mechanism, D: Switch mechanism, E: Viscous liquid damper, 2 ... First pendulum weight, 3 ... 2, pendulum weight, 6,
7 ... external fixed terminal, 9 ... suspension shaft.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Norio Iwakiri, No. 10, Hanazono Todocho, Ukyo-ku, Kyoto-shi, Kyoto Prefecture (56) References Open-ended 62-62226 (JP, U) Open-ended 63- 141432 (JP, U) Japanese Utility Model Sho 62-84717 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01H 1/00

Claims (1)

(57) [Claims] An automatic leveling mechanism having a case having an external fixed terminal, a first pendulum weight mounted in the case and suspended so as to be capable of pendulum movement, A seismic sensor having a second pendulum weight suspended coaxially and installed in the case and pendably movable, and between the automatic horizontal mechanism and the seismic sensor A switch mechanism that is set and comes in contact with and separates from the two pendulum weights in a relative displacement in the horizontal direction; and a damper section that imparts a vibration damping action to the automatic horizontal mechanism section. Is held horizontally to keep the switch mechanism in an open state, and the switch mechanism is moved relative to the first pendulum weight in the horizontal direction based on the seismic motion of the second pendulum weight. The feature is that it is configured to close That seismic device.