JPH055461Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to the improvement of a seismic sensor that detects vibrations such as earthquakes and generates seismic signals.

[Conventional technology]

In order to prevent fires caused by hot appliances or disasters caused by chemicals due to earthquakes, seismic sensors that detect vibrations and generate seismic signals are used. . A seismic sensor is used to take necessary countermeasures when a seismic signal from such a seismic sensor is generated.

For example, it is attached to gas appliances such as gas stoves and gas stoves, gas meters, etc., and generates seismic signals when these gas appliances, gas meters, etc. vibrate. Then, a seismic signal is used to shut off the shutoff valve installed in the gas pipe to prevent a disaster from occurring.

As such a seismic sensor, for example,
62226 is publicly known. This thing is
A seismic switch part that emits a seismic signal when the switch body vibrates is suspended from a holding part, and a damper is interposed between the holding part and the switch body, and the lower part of the damper is integrated with the switch body. ,
It has a structure in which point contact is made between the upper part of the damper and the integral holding part through a pivot and a pivot receiving hole, and the point contact position is the center of sliding of the seismic switch part.

[The problem that the idea attempts to solve]

In the above-mentioned conventional technology (the seismic sensor disclosed in Utility Model Application Publication No. 62-62226), the seismic switch part is suspended from the holding part in order to eliminate the influence of the attitude (tilt) of the device such as a gas meter to which the seismic sensor is attached. Since it employs a mechanism that automatically maintains the level, there are restrictions on how and where it can be fixed in the gas meter, and it has not been possible to attach it directly to the circuit board along with electronic components. In addition, when the entire suspended seismic switch section shakes due to vibrations, a large space is required as an installation space to prevent the seismic switch section from hitting the gas meter case, circuit board, etc. In addition, the suspension mechanism requires many parts and is not only unreliable, but also requires a flexible structure to connect the built-in switch in the suspended seismic switch section to the circuit board outside the seismic sensor. Another problem is that it requires flexible wires and connectors, which increases the number of parts. Furthermore, since viscous fluid is used in the damper, it is troublesome to take measures against liquid leakage. For these reasons, there is also the problem that manufacturing costs are high.

The purpose of the present invention is to propose a seismic sensor that can solve the problems of the prior art described above.

[Means to solve the problem]

In order to achieve the above object, the seismic sensor of the present invention includes a ball having a large mass, a box body with a spherical bottom surface for storing the ball, and a box body placed on the upper end of the ball to accommodate the ball. A detection pin that moves up and down by rolling, a diaphragm that interlocks with this detection pin, an air chamber formed on one side by this diaphragm and having a small hole on the other side, a floating ball placed on the top of this small hole, and this floating ball. It consists of a switch that is linked to the ball.

[Effect]

When subjected to horizontal vibrations such as earthquakes, the ball supported by the spherical surface forming the bottom of the box rolls back and forth in a nearly horizontal plane, and as the ball rolls, it also moves up and down somewhat along the spherical surface of the bottom. . Therefore, the detection pin moves up and down, moving the diaphragm up and down. This upward movement of the diaphragm increases the pressure of the air within the air, causing it to eject through the small holes. As a result, the floating ball floats up and down, activating the switch and emitting a seismic signal. Next, when the diaphragm goes down, the floating ball also goes down and recovers. In this way, the switch turns on and off as the horizontal vibrations of the earthquake occur, emitting seismic signals.

If the equipment to which this seismic sensor is attached is tilted,
Only when the ball is tilted, the ball rolls approximately horizontally from the center of the bottom spherical surface by an amount corresponding to the tilt angle (for example, 5 degrees), and at that time the pressure in the air chamber temporarily increases, causing the detection pin to move upward. However, the amount (for example, 5°)
When the instrument comes to rest just by tilting, the pressure in the air chamber escapes through the gap around the floating ball, and the floating ball rests on the small hole and comes to rest.

In this state, when horizontal vibrations such as earthquakes are applied, the detection pin moves up and down in response to the vibrations, and the pressure in the air chamber also pulsates. Therefore, as mentioned above, the floating ball moves up and down, the switch turns on and off, and a seismic signal is emitted.

〔Example〕

In the embodiment shown in the drawings, reference numeral 1 denotes a ball having a large mass such as a steel ball, and is placed on the bottom surface of a lower case 2 that constitutes a part of the box. Since the bottom surface 2a of the lower case 2 forms a concave spherical surface on the upper surface, the ball 1 comes to rest at the center of this spherical surface (the position shown in the figure). Reference numeral 3 denotes a detection pin placed on the upper end of the ball 1, which consists of a cap-shaped portion 3a overlapping the ball 1 and a rod-shaped portion 3b protruding upward from the center thereof.
It is provided so as to be movable up and down while being guided by a detection pin guide plate 10 fixed to the detection pin guide plate 10 . That is, the detection pin guide plate 10 has a through hole in the center, and the rod-shaped portion of the detection pin 3 is guided in this hole so as to be slidable up and down. Reference numeral 4 denotes an upper case, which is superimposed on the lower case 2 and fixed to each other, and the lower case 2 and the upper case 4 constitute a box body 15.
Reference numeral 5 denotes a switch, and the tip (left end) of one leaf spring constituting this switch extends above the floating ball 6 in order to interlock with the floating ball 6. The floating ball 6 is in the upper case 4
It is placed over a small hole 9 made in the upper wall (ceiling) and is movable up and down within a guide tube 13 formed integrally with the upper case, and is slightly smaller than the inner diameter of the cylindrical guide tube 13. It has a diameter. A diaphragm 7 has the upper end of the detection pin connected to its center, and its outer periphery is airtightly held between the outer edge of the upper surface of the lower case 2 and the outer edge of the lower surface of the upper case 4. An air chamber 8 has a diaphragm 7 on its lower surface and an upper case 4 on its upper and side surfaces. Reference numerals 11 and 12 are air vent holes provided in the bottom surface of the lower case 2 and the detection pin guide plate 10, respectively, that penetrate vertically and are provided so as not to hinder the movement of the diaphragm 7. 14 is a printed circuit board on which electronic components (not shown) are mounted;
It is connected to the switch 5 by two electric wires as shown. Further, the lower case 2 constituting the box body 15 is fixed to the circuit board 14 by appropriate means.

When vibration with an acceleration of, for example, about 120 gal is applied in the horizontal direction, the ball 1 rolls on the bottom surface 2a of the case 2. Since the detection pin 3 is guided by the detection pin guide plate 10 and can move only in the vertical direction, when the ball 1 rolls horizontally from the illustrated position, the detection pin 3 is pushed up and the diaphragm 7 is pushed up. Therefore, the air in the air chamber 8 is compressed, blows out from the small hole 9, and pushes up the floating ball 6. For this reason, switch 5
turns on. After that, when the vibration causes the ball 1 to return to the position shown in the figure, or when the vibration stops and the ball 1 returns to the position shown in the figure, the floating ball 6 descends under its own weight while expelling air from the gap between it and the guide tube. Return to the top of the hole 9 and automatically return to the initial position.

For example, if a gas appliance with a seismic sensor attached is at an angle of 5
Even if the floating ball 6 is tilted, the floating ball 6 will temporarily float due to the movement of the ball according to the acceleration when tilting, but if the device is
Even if the tilt of the degree is maintained, the floating ball will soon reach 6.
returns to its initial state, and when a subsequent earthquake or the like is detected, the switch 5 is activated and generates a seismic signal.

[Effect of idea]

The seismic sensor of the present invention converts the movement of the ball caused by vibration into air discharge through the diaphragm, and also operates a switch by the movement of the floating ball.
Even if the ball is tilted to a certain degree and the position of the ball is shifted from the center of the box, the seismic sensing function will not be hindered. Therefore, there is no need for a hanging mechanism to keep the seismic sensor horizontal, so the structure is simple with fewer parts and has high reliability.

In addition, not only does the installation space become smaller, but there are no restrictions on the installation method, so it can be directly mounted and fixed to the printed circuit board together with electronic components, and the electrical connection between the seismic sensor switch and the circuit board is simplified.

Further, since there is no need to use viscous fluid, there is no fear of liquid leakage, and in this respect, the number of parts can be reduced and the configuration can be simplified. This also contributes to reducing manufacturing costs.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of an embodiment of the present invention. 1... Ball, 2a... Bottom, 3... Detection pin, 5
...Switch, 6...Floating ball, 7...Diaphragm, 8...Air chamber, 9...Small hole, 15...Box.

Claims (1)

[Scope of utility model registration request] A ball 1 with a large mass, a box 15 with a spherical bottom for storing the ball, and a detection pin 3 placed on the top end of the ball and moving up and down as the ball 1 rolls.
and a diaphragm 7 that interlocks with this detection pin.
One side is formed by this diaphragm, and the small hole 9 is formed on the other side.
A seismic sensor consisting of an air chamber 8 having a hole, a floating ball 6 placed above the small hole, and a switch 5 interlocked with the floating ball.