JPH07281670A - Waterproof type piezoelectric buzzer - Google Patents

Abstract

PURPOSE:To provide a buzzer which is compact, has nearly perfect waterproofness, is easy to assemble and facilitates production by building a piezoelectric vibrating diaphragm and a wiring board into one piece of case. CONSTITUTION:A case body 1 is provided with a housing part 8 which is opened on a rear surface side and has two steps of annular step parts 10, 11 on its inner peripheral surface. The piezoelectric diaphragm 4 and the wiring board 5 inserted with an annular gasket material 6 on its outer periphery are fitted therein. Lead wires 3 inserted into the block part 15 on one side of the gasket material 6 and the lead wires 16 of the piezoelectric vibrating diaphragm are connected to the wiring board 4 and a rear cap 7 fitted into the housing part from the rear surface side of the case body is screwed to the peripheral edge of the case body to compress the gasket material and the block part fitted into the window hole 12 of the case body. The waterproof type piezoelectric buzzer which is subjected to waterproofing around the housing part and the window part and in the insertion part of the lead wires and is made compact is thus obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof type piezoelectric buzzer in which a wiring board is incorporated together with a piezoelectric vibrating plate, and the piezoelectric buzzer can be formed compactly and easily assembled, and an almost completely waterproof structure can be formed. It was done like this.

[0002]

2. Description of the Related Art In a conventional piezoelectric buzzer, for example, as disclosed in Japanese Utility Model Laid-Open No. 4-90000, a case main body is provided with an annular step portion on an inner peripheral surface of a housing portion whose rear surface side is open, and a peripheral edge of a piezoelectric vibrating plate. There is one in which the piezoelectric vibrating plate is only built in the case body by stacking the parts and press-fitting the back end with the annular peripheral part and the annular large diameter part from the open end to the outer peripheral surface. Since the wiring portion for driving the piezoelectric element is separately provided outside the main body, it is not formed compactly, and there is a drawback that it is inferior in waterproofness.

As a waterproof type piezoelectric buzzer, for example, as disclosed in Japanese Utility Model Laid-Open No. 4-119497, there is a piezoelectric buzzer which is covered with a horn frame. Since it requires a large space, its use is limited. Further, since the piezoelectric buzzer also does not have a built-in wiring portion for driving the piezoelectric element, it is necessary to mount it on another body and connect its lead wire to the piezoelectric element in the buzzer.

[0004]

As described above, there is no conventional piezoelectric buzzer having a built-in wiring portion for driving the piezoelectric element, and the buzzer body and the driving portion are separately manufactured and connected. Therefore, the number of parts is increased, labor is required, and a special waterproof structure for connection is required, resulting in high cost. Moreover, the buzzer becomes large due to the attachment of the waterproof structure. Note that, for example, as disclosed in Japanese Utility Model Laid-Open No. 5-13889, there is one in which a piezoelectric buzzer is incorporated together with a wiring board in a body composed of a case body and a lid. Since it was a motorcycle anti-theft alarm device that gave an alarm when a vibration sensor or the like was installed and it was tilted inadvertently, its body became large and it could not be diverted to a waterproof piezoelectric buzzer immediately.

From the above, for example, in a waterproof type piezoelectric buzzer which is attached to an automobile or the like, a power distribution board is incorporated together with a piezoelectric vibrating plate to form a compact body, which facilitates assembly of the buzzer and improves the waterproof structure. It was a problem to be solved to be fully prepared.

[0006]

In order to solve the above-mentioned problems, the present invention is a piezoelectric buzzer provided with a case body, a piezoelectric vibrating plate, a wiring board and a back cover, the case body having a back side. An open substantially cylindrical housing is provided, the peripheral edge of the piezoelectric vibrating plate is fixed to a first annular step provided on the inner peripheral surface of the housing, and the wiring board is formed into a U-shaped cross section. Fit the peripheral part to an annular packing material with a peripheral groove on the peripheral surface,
Along with the packing material, the packing material is fitted to a second annular step formed on the inner peripheral surface of the case body, and the packing material is integrally molded on one side thereof with a block portion into which the lead wire is watertightly inserted. Fitted in a window hole provided on one side of the case body, and a groove provided from the upper surface of the block portion to both left and right side surfaces is fitted to the edge of the window hole. Is tightly fitted to the back side of the packing material and the block portion and is screwed to the case body while pressing the packing material. The waterproof piezoelectric buzzer is characterized in that the insertion portion of the lead wire connected to the diaphragm is waterproofed by the packing material and the block portion.

In the piezoelectric buzzer of the present invention, a projecting edge portion is integrally formed on one side of the back cover, and the projecting edge portion is superposed on the lower surface of the block portion and fitted into the window hole of the case body. The protrusions protruding to the left and right of the projecting edge are fitted into the recesses provided on both sides of the window hole, and the screw hole stoppers provided on the other side of the back cover are opposed to the window hole to form the case body. It is configured to be fitted to a screw receiving seat provided on the other side, and to be screwed into the screw hole of the screw receiving seat while pressing the block portion from the back side, and the side surface of the back lid and the case body. By providing a convex part on one of the fitting parts with the inner peripheral surface and a concave part on the other part to elastically fit each other, the screwing position of the back cover can be done at one place, and it is waterproof and robust. You can also make it easier to assemble the buzzer without compromising

[0008]

In the piezoelectric buzzer of the present invention constructed as described above, as shown in FIG. 1, the case main body is placed upside down, the piezoelectric vibrating plate is fitted into the accommodating portion, and is bonded to the first annular step portion. Then, an annular packing material is fitted to the peripheral portion of the wiring board, and the lead wire inserted into the block portion and the lead wire from the piezoelectric vibrating plate are respectively connected to predetermined terminals of the wiring board. , It is fitted into the second annular step inside the case body, and is closely fitted using the elasticity of the packing material.
Then, by a three-step simple assembling operation of fitting the back cover into the housing and pressing the peripheral edge of the packing material and screwing the packing material together, the piezoelectric vibrating plate and Complete a piezoelectric buzzer with a built-in wiring board.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the buzzer of the present invention includes a case body 1
A piezoelectric vibrating plate 4 in which the piezoelectric elements 2 are integrally attached to the back surface and the ends of the lead wires 3 are connected to each, a wiring board 5 in which a peripheral edge portion 5'is fitted to an annular packing material 6, and a case The back cover 7 is fitted from the back side of the main body 1.

The case body 1 is turned upside down in FIG. 1 and has a housing portion 8 having a substantially cylindrical shape with the back side which is the upper surface in FIG.
A bottomed resonance cylinder portion 9 is formed on the front side of the inside to provide a first annular stepped portion 10, and an accommodation space for an electric component is formed between the first annular stepped portion 10 and the second annular stepped portion 11. Is provided, and a little height is set further on the back side of the second annular step 11, and the case body 1
A window hole 12 that opens to the side surface of is formed, and a screw seat portion 13 that is diametrically opposed to the window hole 12 and extends in a trapezoid is integrally formed.

Piezoelectric diaphragm 4 to which lead wire 3 is connected in advance
Is an appropriate fixing means such as adhering the overlapping surface of the peripheral portion and the first annular step portion 10 or forming an inward circumferential groove at that position of the accommodating portion 8 and elastically press-fitting it. It is used and fixed at a predetermined position in the housing portion 8.

The packing material 6 is made of rubber, and as shown in FIG. 1, the peripheral edge portion 5'of the wiring board 5 is fitted into the peripheral groove 14 formed in the inner peripheral surface of the packing material 6 by molding it in a U-shaped cross section. In addition, a thick block portion 15 having substantially the same shape is integrally provided at a position aligned with the window hole 12. The wiring board 5 has an inner end of a lead wire 16 which is inserted through the block portion 15 laterally,
The tip ends of the lead wires 3 of the piezoelectric vibrating plate 4 in the accommodating portion 8 are connected to predetermined terminals, respectively, and fitted into the accommodating portion 8 of the case body 1 together with the packing material 6, and the elasticity of the packing material 6 causes It is fitted to the two annular step portions 11.

In addition to the left and right through holes 17 through which the lead wires 16 are inserted in a watertight manner, the block portion 15 is provided with a non-through hole 18 in the center so that three-phase use is also possible (FIG. 2 and 3). And this block part 15
Along with the fitting of the wiring board 5, the wiring board 5 is fitted into the window hole 12 opened on the side surface of the case body 1, and is provided corresponding to the thickness of the side surface of the case body 1 from the upper surface of the block portion 15 to both left and right side surfaces. The groove 19 is elastically fitted to the edge of the window hole 12 to shut off the three sides of the window hole 12 in a watertight manner.

The back cover 7 is constructed so as to be superposed on the back side of the packing material 6 and the block portion 15 and tightly fitted into the housing portion 8 of the case body 1 while pressing the packing material 6 and screwed. Has been done. As shown in FIGS. 2 and 3, the back cover 7 is
The outer peripheral side surface is tightly fitted in the housing portion 8 of the case body 1, and the projecting edge portion 20 integrally formed on one side thereof is superposed on the lower surface of the block portion 15 and fitted in the window hole 12 of the case body 1, The convex portions 21 protruding left and right of the projecting edge portion 20 are fitted into the concave portions 22 provided on both sides of the window hole 12, and the stopper portion 24 with the screw hole 23 provided on the other side of the back cover is opposed to the window hole 12. 2 is fitted to the screw seat portion 13 on the other side of the case main body 1, and as shown in FIG. The material 6 and the block portion 15 are pressed from the front and back, and the housing portion 8 and the back lid 7 are pressed.
It is configured to provide a watertight cutoff between and.

Further, the back cover 7 is provided with a convex portion 27 on one of the fitting surfaces of the side surface of the back lid 7 and the inner peripheral surface of the case body 1 and a concave portion 28 on the other side in the process of screwing. The back cover 7 and the packing material 6 are elastically fitted to each other.
It is also designed to be able to hold the pressure bond with and more firmly and irreversibly. Further, in this embodiment, an annular recess 29 is provided on the back side of the packing material 6 so that the back cover 7 and the packing material 6 are kept pressure-tight.
It should be noted that instead of the recess 29, an annular protrusion is used as the packing material 6.
The packing material 6 can be more firmly compressed by being provided on the back side of the back cover 7 or on the inner side of the peripheral portion of the back cover 7, but the back cover 7 and The watertightness of the joint surface may be maintained only by pressure contact with the packing material 6.

The present invention is not limited to the embodiment in which the back cover 7 is screwed at one place. For example, a plurality of screw seats are provided at appropriate intervals on the periphery of the opening of the case body 1 to face each other. Then, a screw may be inserted through a screw hole provided in the peripheral portion of the back cover 7 and screwed at a plurality of positions. As described above, the back cover 7 is tightened to the case body 1 with the packing material 6 interposed therebetween, and the piezoelectric vibrating plate 4 and the wiring board 5 are incorporated in the case body 1. The lead wire 16 connected to the piezoelectric vibrating plate 4 and the case body 1 are almost completely waterproofed by the packing material 6 and the block portion 15.

[0018]

According to the present invention configured as described above,
Since the piezoelectric vibrating plate and the wiring board can be housed in the same body, the waterproof piezoelectric buzzer can be made compact with a small number of parts and installed in a narrow space. Further, according to the present invention, the piezoelectric vibrating plate to which the lead wire is connected is fitted to the first annular step portion in the accommodating portion of the case main body whose rear side is opened, and then the lead portion is attached to the block portion provided on one side. The wiring board in which the peripheral portion is fitted in the circumferential groove of the packing material having a U-shaped cross section through which the wire is inserted, and the lead wire of the piezoelectric vibration plate and the lead wire inserted in the block portion are connected to predetermined terminals respectively, Fit into the case body and elastically fit into the second annular step inside the accommodating part, fit the block portion of the packing material into the window hole on the side surface of the case body, and from the upper surface of the block portion to the left and right sides. The groove provided over the surface is elastically fitted to the edge of the window hole, then the back side of the case body is fitted tightly into the housing to press the packing material and the block, and the back lid is fitted. Screw the case back to the case body It is possible to complete a piezoelectric buzzer with a built-in wiring board piezoelectric vibrating plate by the operation of the three steps that firmly tightening the body and a back lid, assembling operation is facilitated,
Can be manufactured at low cost.

Further, the accommodating portion containing the piezoelectric vibrating plate and the wiring board and the window hole on the side surface of the case body are blocked by the packing material and the block portion which are interposed between the tightened back cover and the case body. Since it is waterproof, it has sufficient waterproofness without increasing the size of the body. As described above, the present invention is excellent in that it is possible to provide a compact waterproof piezoelectric buzzer that is sufficiently waterproof and has a built-in wiring board together with a piezoelectric vibrating plate in one case body by a simple assembling operation. effective.

[Brief description of drawings]

FIG. 1 is a partially cutaway exploded perspective view showing an embodiment of the present invention.

FIG. 2 is a partially cutaway elevation view showing an assembled state.

FIG. 3 is a partially cutaway side view showing an assembled state.

[Explanation of symbols]

 1 Case Main Body 2 Piezoelectric Element 3 Lead Wire 4 Piezoelectric Vibrating Plate 5 Wiring Board 5 ′ Peripheral Part 6 Packing Material 7 Back Lid 8 Receiving Section 9 Resonance Section 10 First Annular Step Section 11 Second Annular Step Section 12 Window Hole 13 Screw seat portion 14 Circumferential groove 15 Block portion 16 Lead wire 17 Through hole 18 Non-through hole 19 Groove 20 Projected edge portion 21 Convex portion 22 Recessed portion 23 Screw hole 24 Stop portion 25 Screw hole 26 Screw 27 Convex portion 28 Recessed portion 29 Annular recessed portion

Claims (2)

[Claims] 1. A piezoelectric buzzer including a case body, a piezoelectric vibrating plate, a wiring board, and a back cover, the case body having a substantially cylindrical accommodating portion whose rear side is open, and an inner circumference of the accommodating portion. The peripheral portion of the piezoelectric vibrating plate is fixed to the first annular stepped portion provided on the surface, and the wiring substrate is fitted into the annular packing material having a U-shaped cross section and having a peripheral groove on the inner peripheral surface. Together with the packing material, the packing material is fitted into a second annular step formed on the inner peripheral surface of the case body, and the packing material is
A block part, which is integrally molded on one side and has the lead wire inserted in a watertight manner, is fitted into a window hole provided on one side of the case main body, and a groove formed from the upper surface of the block part to both left and right side surfaces is formed. The back cover is fitted to the edge of the window hole, and the back cover is tightly fitted in the housing portion of the case body, and is overlapped on the back side of the packing material and the block portion and screwed to the case body while pressing the same. The waterproof piezoelectric buzzer, which is configured to be stopped, is waterproof between the back cover and the case body and the insertion portion of the lead wire connected to the piezoelectric vibrating plate by the packing material and the block portion. . 2. The back cover is fitted to the window hole of the case main body by overlapping a projecting edge portion integrally formed on one side thereof with the lower surface of the block portion and projecting to the left and right of the projecting edge portion. The protrusions provided are fitted into the recesses provided on both sides of the window hole, and the screw hole stopper provided on the other side of the back cover is provided on the other side of the case body so as to face the window hole. And is configured to be screwed into the screw hole of the screw seat portion while pressing the block portion from the lower surface, and the side portion of the back lid and the inner peripheral surface of the case body are fitted with each other. By providing a convex portion on one side and a concave portion on the other side and elastically fitting each other,
2. The waterproof piezoelectric buzzer according to claim 1, wherein the back cover is screwed at one position.