JPH0723706Y2 - Assembly structure of seismic device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Use The present invention relates to a seismic sensing device that detects a vibration caused by an earthquake and outputs a signal, and is particularly mounted on a gas meter or the like to shut off a gas flow path when an earthquake occurs. The seismic sensitive device.

(B) Conventional technology Households equipped with a seismic sensing device that detects vibrations caused by an earthquake to prevent secondary disasters after the occurrence of an earthquake, and shut off the gas flow path when the seismic sensing device detects a signal. There is a gas meter for. As a seismic sensing device used in such a gas meter, a seismic sensing device disclosed in Japanese Utility Model Laid-Open No. 61-48325 is equipped with a steel ball inside a casing having a conical inner bottom surface, and the steel ball is caused by vibration of the casing. Movement is transmitted via the concave spherical surface and the pressing plate, and the seismic switch part is configured to open and close the contacts of the switch mechanism. The seismic switch part can be swung in the liquid sealed chamber via the suspension shaft. Is supported by. With this configuration, the inclination of the mounting posture of the seismic sensing unit can be corrected to the horizontal posture by its own weight.

(C) Problems to be Solved by the Invention However, since the conventional seismic sensing device is configured to transmit the operation of the steel ball to the contact of the opening / closing mechanism of the switch,
A complicated structure with a transmission mechanism is required, which leads to an increase in cost and is likely to be damaged by impact. Further, since the vibration is detected by the movement of the steel ball on the inner bottom surface of the conical shape, it is difficult to adjust the setting sensitivity after manufacturing, and there is a problem that the yield of the product deteriorates. In addition to the seismic switch section, a liquid ring chamber with a complicated shape is required, which also increases the cost due to an increase in the number of parts, and the size and shape cannot be mounted on the printed circuit board. There was a problem.

Therefore, in the Japanese Patent Application No. 2-62419, the present applicant transmits the movement of the fluid due to the vibration of the earthquake to the piezoelectric plastic film, and detects the voltage generated by the piezoelectric phenomenon from the piezoelectric plastic film to detect the vibration of the earthquake. Detecting and reducing the number of parts with a simple structure to downsize the device, mounting on a printed circuit board, cost reduction, excellent impact resistance, and easy adjustment of setting sensitivity I proposed a seismic sensing device that can be used.

The purpose of this invention is to mount two insert members laminated so as to sandwich the upper end of the piezoelectric plastic film on a lid that seals a case for containing a fluid, and to mount the upper end of the piezoelectric plastic film via a conductive rubber. It is possible to assemble a seismic sensing device that detects the earthquake by detecting the voltage generated in the piezoelectric plastic film due to the movement of the fluid, from a single direction. An object of the present invention is to provide an assembling structure that can improve the yield of products by automating the assembling work and realize the cost reduction.

(D) Means for Solving the Problems In the assembly structure of the seismic sensing apparatus of the present invention, the lower ends of the two piezoelectric plastic films are perpendicular to the sides of the fluid contained in the case sealed by the lid. Then, the upper end of the piezoelectric plastic film is electrically connected to one end of the lead metal fitting insert-molded in the lid body via the conductive rubber on the inner surface of the lid body to support the conductive rubber. The first insertion member and the second insertion member for stacking and sandwiching the upper end of the piezoelectric plastic film between the first insertion member and the first insertion member are mounted on the inner surface of the lid.

Further, a columnar protrusion is made to protrude vertically downward from the center of the inside surface of the lid body, and at least two flat plate-shaped protrusions circumscribing the peripheral surface of the protrusion are mutually provided at the center of the first insertion member. It has a right angle and is formed so as to project vertically downward.

(E) Action In the present invention, the upper end of the piezoelectric plastic film is placed on the second insert member, and the first insert member is placed on the upper end of the piezoelectric plastic film from above so that the first insert member and the first insert member The upper end of the piezoelectric plastic film is sandwiched between the first insertion member and the second insertion member, the conductive rubber is positioned so as to contact the upper end, and the first and second insertion members are inserted into the lid body in which the lead metal fitting is insert-molded. When the piezoelectric plastic film and the conductive rubber are mounted, the upper end of the piezoelectric plastic film is electrically connected to the lead metal fitting through the conductive rubber. As described above, the seismic sensing device can be assembled by fitting the lid body on which each component is mounted into the opening on the upper surface of the case containing the fluid. In this assembling work, the work of placing the upper end of the piezoelectric plastic film on the second insert member, the work of sandwiching the upper end of the piezoelectric plastic film between the first insert member and the second insert member, the piezoelectric plastic The work of setting the conductive rubber in contact with the upper end of the film, the work of mounting the first insert member and the second insert member having the piezoelectric plastic film and the conductive rubber set on the inner surface of the cover, and the cover All the work of fitting on the upper surface of the case is performed from above. Therefore, the assembly work of the parts can be performed only from a single direction, which is suitable for automation of the assembly work.

Further, when a columnar protrusion is provided on the inner side surface of the lid body and at least two flat plate-shaped projecting pieces circumscribing the protrusion are formed perpendicularly downward with respect to each other, a first protrusion is formed on the inner side surface of the lid body. When the insertion member is mounted, at least two projecting pieces form a right angle, and the piezoelectric plastic films are positioned by using this as a guide, so that the side surfaces of the two piezoelectric plastic films form a right angle. Therefore, when the first and second insertion members holding the horizontal portion of the piezoelectric plastic film are mounted on the inner surface of the lid, the piezoelectric plastic film is positioned at the same time.

(F) Embodiment FIG. 1 is a front sectional view of a seismic sensing device to which an assembly structure according to an embodiment of the present invention is applied.

The vibration-sensing device 1 accommodates a fluid such as silicone oil 21 inside a substantially cylindrical case body 2 and seals the case body 2 with a lid body 3 while holding a piezoelectric plastic film 4 held by the lid body 3. The lower ends of the and 5, 5 are immersed in the silicone oil 21. The piezoelectric plastic film 4 is held on the inner surface of the lid 3 together with the first inner case (first insertion member) 6, the second inner case (second insertion member) 7 and the conductive rubber 8. . The inner cases 6 and 7 are made of an insulating material. A lead metal fitting 9 is insert-molded on the lid body 3, and one end of the lead metal fitting 9 is formed on the inner surface of the lid body 3.
9a is exposed. The piezoelectric plastic film 4 and the piezoelectric plastic film 5 are held so that their side surfaces form a right angle. Piezoelectric plastic film
The horizontal portions 4a and 5a formed at the upper ends of the four and four are electrically connected to one end portion 9a of the lead fitting 9 through the conductive rubber 8. Further, a packing 10 is provided on the upper edge of the inner peripheral surface of the case main body 2, so that the second inner case 7
The water tightness is secured between the lower end of the and.

2 (A) and 2 (B) are a front sectional view and a bottom view, respectively, of a lid constituting the seismic sensing device. Also,
3 (A) and 3 (B) are a plan view and a front sectional view of the same first inner case. Further, FIGS. 4A and 4B are a plan view and a front sectional view of the second inner case, respectively. Further, FIGS. 5 (A) to (C) and FIGS. 6 (A) to (C) are a plan view, a front view and a side view, respectively, showing the same piezoelectric plastic film.

The lead fitting 9 is insert-molded on the lid body 3,
One end 9a of the lead fitting 9 is exposed on the inner side surface 3b of the lid 3. At the center of the inner side surface 3b of the lid body 3, a cylindrical projection 11 is formed so as to vertically project downward. This protrusion
Four projecting pieces 12 projectingly formed at the central portion of the first inner case 6 shown in FIG. The distance between the projecting pieces 12 facing each other is made slightly smaller toward the lower side, and the inner surface of the projecting piece 12 is projected downwardly.
Press contact with the circumference of 11. As a result, the first inner case 6 is fixed to the lid 3, and the angles formed by the protruding pieces 12 adjacent to each other become a right angle. The inner case 6
Small holes 13 and 14 are formed at 6 positions, and square holes 18 are formed at 4 positions. The small holes 13 and 14 are used for positioning the second inner case 7 and the piezoelectric plastic films 4 and 5, as described later. The conductive rubber 8 (not shown) is located in the square hole 18.

The second inner case 7 has a square hole 17 formed in the central portion thereof, and convex portions 15 and 16 are formed at a total of 6 places. Further, locking pieces 7a are formed at four locations on the outer peripheral surface of the second inner case 7. The first inner case 6 is superposed on the second inner case 7 from above. At this time, the protrusion 12 is inserted into the square hole 17.
Further, the convex portions 15 and 16 are fitted into the small holes 13 and 14, and the first inner case 6 and the second inner case 7 are positioned. The engagement piece 7a engages with the engagement recess 3a when the second inner case 7 is attached to the inner surface of the lid 3. By this engagement, the second inner case 7 is held by the lid 3.

The second inner case 7 and the first inner case 6
In between, the horizontal portions 4a, 5a formed by being reinforced by the reinforcing plate are placed on the upper ends of the piezoelectric plastic films 4, 5 shown in FIGS. The horizontal electrodes 4a, 5a of the piezoelectric plastic films 4, 5 have electrodes on the lower surface formed on the upper surface by folding back one end. Small holes 4b are formed in the horizontal portion 4a of the piezoelectric plastic film 4 shown in FIG. 5 at three locations. The horizontal portion 4a is formed by inserting the projection 15 of the inner case 7 into the small holes 4b. 7 is placed on the upper surface. In addition, the horizontal portion 5a of the other piezoelectric plastic film 5 shown in FIG.
A small hole 5b is formed at a position, and the horizontal portion 5a is placed on the upper surface of the inner case 7 so that the convex portion 16 is fitted into the small hole 5b. In this way the piezoelectric plastic film 4,
When the horizontal parts 4a and 5a of 5 are placed on the second inner case 7, the piezoelectric plastic films 4 and 5 are placed on the inner case 7.
It is located inside the square hole 17 and extends below the inner case 7. After placing the horizontal parts 4a, 5a on the inner case 7 and mounting the piezoelectric plastic films 4,5, the horizontal parts 4a, 5a
When the inner case 6 is superposed on the inner case 7 so as to sandwich the piezoelectric plastic film 4, the piezoelectric plastic films 4 and 5 are located between the inner wall surface 17a of the square hole 17 and the outer surface of the projecting piece 12. In this state, when the projecting piece 12 is put on the peripheral surface of the projecting piece 11, the projecting piece 12 is elastically pushed outward and is opened.
The piezoelectric plastic films 4 and 5 are sandwiched between the outer surface of the and the inner surface of the square hole 17.

FIG. 7 is an assembly drawing of the seismic sensing device.

When assembling the vibration-sensing device 1 configured as described above, first, the horizontal portions 4a, 5a are formed on the upper surface of the second inner case 7.
Then, the piezoelectric plastic films 4 and 5 are mounted from above so as to be mounted. Next, the first inner case 6 is placed by inserting the protruding piece 12 into the square hole 17 of the second inner case 7. At this time, the convex portions 15 and 16 of the second inner case 7 are the small holes of the piezoelectric plastic films 4 and 5.
The piezoelectric plastic films 4, 5 and the first inner case 6 are positioned with respect to the second inner case 7 by fitting the holes 4b, 5b and the small holes 13, 14 of the first inner case 6.

Further, the conductive rubber 8 is placed in the square hole 18 of the first inner case 6 from above, and the lid body 3 is covered from above these first and second inner cases 6 and 7. As a result, the engagement piece 7a formed on the second inner case 7 is attached to the lid 3
The first and second inner cases 6 and 7, the piezoelectric plastic film 4,5 and the conductive rubber 8 are attached to the lid 3 by engaging with the engaging recess 3a formed in the piezoelectric plastic film 4,5. Is electrically connected to the lead fitting 9 through the conductive rubber 8.

On the other hand, the packing 10 is attached to the case body 2 from above, and the silicone oil 21 is further injected from above. In this way, the lid body in which the inner cases 6, 7 etc. are attached to the case body 2 in which the packing 10 is attached and the silicone oil 21 is injected is attached from above from the engagement hole 3c of the lid body 3 and the case body 2. The case body 2 is hermetically sealed by the lid 3 by fitting with the fitting protrusion (not shown), and
Is completed.

As described above, all the parts can be assembled from a single direction when assembling the vibration-sensing device 1, and the assembling work can be easily automated.

Although the four protrusions 12 are formed on the first inner case 6 in the present embodiment, at least two protrusions 12 forming a right angle with each other may be formed.

(G) Effect of the Invention According to the present invention, all the parts constituting the seismic sensing device can be assembled from the same direction, which facilitates automation of the assembly work to improve product yield and reduce cost. There are advantages that can be realized.

In addition, the projection piece 12 formed on the first insertion member can accurately position the piezoelectric plastic film, and the two piezoelectric plastic films can be positioned at right angles.

[Brief description of drawings]

FIG. 1 is a sectional view of a seismic sensing device to which an assembly structure according to an embodiment of the present invention is applied, and FIGS. 2 (A) and 2 (B) are front sectional views of a lid constituting a part of the seismic sensing device. Drawings and bottom views, FIGS. 3A and 3B are plan views and front sectional views of the first inner case, respectively, and FIGS. 4A and 4B are second inner cases, respectively. Plan view and front sectional view, FIGS. 5 (A) to (C)
6 (A) to 6 (C) are a plan view, a front view, and a side view of the piezoelectric plastic film, respectively, and FIG. 7 is an assembly view of the vibration-sensing device. 1 ... Earthquake-sensing device, 2 ... Case body, 3 ... Lid, 4,5
...... Piezoelectric plastic film, 6 ... First inner case (first insertion member), 7 ... Second inner case (second insertion member), 8 ... Conductive rubber, 9 ... Lead fitting .

Claims (2)

[Scope of utility model registration request] 1. A lower end portion of two piezoelectric plastic films is dipped in a fluid housed in a case hermetically sealed by a lid body so that their side surfaces are perpendicular to each other, and an upper end of the piezoelectric plastic film is placed inside the lid body. The first insert member, which is electrically connected to one end of the lead metal fitting insert-molded on the lid body through the conductive rubber and supports the conductive rubber, is provided between the first insert member and the first insert member. A structure for assembling a vibration-sensing device, characterized in that a second insertion member for placing and holding an upper end of a piezoelectric plastic film is mounted on an inner surface of a lid. 2. A flat plate-shaped projection which vertically protrudes downward from a central portion of an inner surface of the lid body and which circumscribes a peripheral surface of the projection at a central portion of the first insertion member. 2. The seismic sensing device assembly structure according to claim 1, wherein the two projecting pieces are formed so as to project vertically downward so as to form a right angle with each other.