JPS6018099A - Assembling method of piezoelectric buzzer - Google Patents

Abstract

PURPOSE:To ensure the assured adhesion of a sound generator at a nodal point by forming plural through holes having the same external shape as the sound generator in terms of each space to a case. CONSTITUTION:A sound generator 12 is obtained by adhering a piezoelectric element 14 formed with an electrostrictive material such as lead titanate and zirconate, etc. into a disk shape to a metallic disk-shaped elastic thin plate 16. The nodal point of the generator 12 exists concentrically at a prescribed distance from the center point. A case 20 made of synthetic resin is formed into a dish shape opened at an end together with a ring-shaped projection 20b coincident with the nodal point of the generator 12 formed at the ceiling part 20a. Then plurl through holes 20c having the inner diameter equal to the outer diameter of the plate 16 are formed to the fringe of the ceiling part of a case 10. Then the generator 12 is fixed to the case 10 by means of a base board 24 containing guide ribs 22 to be inserted into the holes 20c respectively.

Description

[Detailed description of the invention] The present invention relates to an improved method of assembling a piezoelectric buzzer.

Conventional piezoelectric buzzers, which generate sound waves by applying electric force to a piezoelectric element such as P Z 1' pasted on an elastic thin plate, are each mounted on a scale with d3, -1s ( Figure 1 shows examples of +.

The iJ'ffE space block IJ"- shown in the same figure is a synthetic (■1 resin circular vessel-shaped case 20, etc., a disc-shaped phosphor element J"l/I
is a circle (k-shaped elastic thin plate 16).
I stored it inside the Risu 20 and took it out. The structure for fixing the first break 12 to the case 20 is such that a projection 7'Jl 2 (,
) An adhesive such as silicone rubber was applied to the tip of the It to avoid contact with the elastic thin plate 16 of the light body 12. .

How to assemble a piezoelectric buzzer with this structure (well, case 2)
After applying adhesive 2G to the projection 201J of 0, the sounding body 124 was inserted into the case, and the thin elastic plate 16 was bonded with adhesive 26.

However, this assembly method had some drawbacks as shown below.

1, that is, the sound wave of the piezoelectric bulb 1 of this scale is light n 12
By applying a force to the mold opening through the lead terminal for external connection, bending vibration is generated.

Therefore, the vibration characteristic of the piezoelectric bulb 1F- is that the sounding body 12 is moved to the position A'() by the diluent 26 at the node of the bending vibration, that is, the nodal point 1~. I want J Niji without losing 1.

However, in the conventional assembly method, for example, the elastic thin plate 1G
Add the two-dual point 1- to the top with a smaller IJl mark fJ #JC
However, inside the case 20, this is of no use as it is moved backwards on the opposite side.
It was confirmed by J and sea urchin striking l, which are located concentrically with the outline of G.

For this reason, the bonding position of the sounding body 12 is often attached to the nodal point which is extremely narrow, and the sounding performance f(1) of the piezoelectric buzzer varies greatly.

In order to solve this problem, for example, it is possible to measure the gap between the elastic thin plate 16 and the case 20 with a feeler gauge after gluing the sounding body 12, but it is complicated to measure them individually, and There is also the problem that it takes time to repair because defective products are detected later.

This invention was made in view of the conventional problem of ``:d''>shi7g+, and its purpose is to reliably and easily obtain the nodal point of the buto rS body. We provide a method for assembling a piezoelectric buzzer that can be fixed and covered at the same time and that does not cause dispersion in the six locations per person.
It's possible to get there.

In order to achieve the above purpose, we will use piezoelectric power for every moment of this emission.”
- As a setting method (13 C1 book-shaped wreath, on the inner surface of the large moon part, a protrusion is formed in advance that protrudes inward and touches the nodal point 1 ~ of the light n formation. A plurality of through holes are drilled through this man-month part, and the distance between these six holes is determined by inserting a guide rib into each of the six holes. After that, the outer peripheral end of the sounding body was brought into contact with the inner surface of the JJ guide rib, and inserted into the case. It is characterized by

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

In the following description, the same reference numerals are used for parts that are the same as or correspond to those of the conventional example described above.

FIG. 2 shows an embodiment of the piezoelectric buzzer assembly method according to the present invention.

First, the piezoelectric buzzer 10 that is assembled by the assembly method 1 shown in FIG. 161 will be explained.
is roughly composed of a sounding body 12 and a case 20.
The sounding body 12 is made by attaching a piezoelectric element 14 made of an electrostrictive material such as ditanate lead phosphate into a disc shape to a thin elastic plate 16 made of h9H metal using an adhesive or the like. The nodal point of the sounding body 12 lies in a concentric circle spaced a predetermined distance from the center point of the sounding body 12.

” - Notes - The space 20 is made of synthetic resin C molded from a polyurethane cap, and has a dish shape with one end open.
There is a ring-shaped protrusion 2 that is tapered and protrudes inward.
01) is provided in a protruding manner, and the diameter of this ring-shaped protrusion 201) is as follows:
It coincides with the nodal point 1 to the diameter of the sounding body 12 and is -C.

On the periphery of the ceiling part 20a of the case 10, there are three groove-shaped through holes 20C that are oriented at an equal angle to the center point of the circular ceiling part 20a. The diameter connecting the inner periphery of each of the through holes 20c is substantially the same as the sunset z of the elastic thin plate 16 of the sounding body 12. There is.

In the case 20 configured as described above, lnγ′1 and 12
In order to securely cover the sea urchin, first, as shown in FIG. Zu-
Three wooden guide ribs 22 are erected on the same circular surface connecting the centers of each of the through holes 20c, and have the same diameter as the width of the through holes 20c and the diameter of the fruit Y1. A base 24 with
are inserted so that each guide rib 24 is positioned inside the through hole 20 ().

After this, a predetermined amount of adhesive 2 (3) such as silicone rubber is applied to the tip of the ring-shaped protrusion 20b of the case 10, and then a thin elastic plate 1G of the fS body 12 is applied to the inner surface of the guide rib 22. The outer circumferential end is brought into contact with the ring-shaped protrusion 201 by inserting it from the open end of the case 10 and fixing it on the ring-shaped protrusion 201 with adhesive 26t.

Once the adhesive 2G has solidified, the guide rib 22 is inserted into the through hole 2.
If you pull it out from inside Qc, you will be able to complete the assembly of electric bulb 1f-10.

Well, 1. When piezoelectric buzzer 10 is assembled using the method described above,
The outer shape of the light body '12 is defined by the guide ribs 22.
) ↓1 Since it can be inserted into the case 1o in a restrained state, it is possible to accurately and reliably draw the same meaning on the ring-shaped protrusion 2Oc set at the nodal point of the light 141 water 12, and the adhesive 26 It will solidify in this state.
f (held, firing 7; one body 12 is Notal Boin 1
There is no chance of it coming off and getting stuck.

In this case, the sounding body 12, which is fixed by the conventional visual inspection method, is fixed outside of the nodal point 1. )? Since it is possible to eliminate variations in the sound production characteristics, such as those that hinder the bending photography of the piezoelectric actuator '12 and increase the loss of electricity-to-sound conversion, Can be assembled.

Also, when assembling the piezoelectric buzzer 10, the sounding body 12 may come off the nodal point (as described above).

Assembly 11 is eliminated because assembly defects caused by
゛■ni J3
T! 2 L: +3 There is no need to train, and it becomes N\'s pure side Cchi Ishikawa <lll'b.

Furthermore, it should be noted that the hole 20C is formed in the large moon part of the case '10 when the kite rib 22 is inserted at the time of the phase). 1' Exercising the 1 function shown in the J strike is CiJ'>.

In other words, normally, the II electric bulb IJ'-10 of this scale has a "notch" generated outwardly in the center of the large moon part 10a of the case 20, as shown in Fig. 1 J3 and Fig. 2. ? A central through hole 20d is formed to emit waves to
．． ．． A low power that emits X7°'1 waves to the outside.

. Therefore, as described above, the sounding body 12 has a notal voice 1
(4-J, electric-t1 modification 1) is reduced and the sound pressure is increased (0 (J), this large sound pressure is added to the central through-hole 2Qtll (transparent). Since the sound can be emitted to the outside through the hole 20C, the spread of sound is expanded.

a3, a ring-shaped protrusion 2 formed protrudingly on the case 20;
01+ is not limited to a ring that goes around the ring, but may be formed intermittently.

In addition, if there are a plurality of through holes 20Cb drilled in the case 20, it is not necessary to limit the shape of the holes to the holes 20Cb.

The above is a detailed explanation of the embodiment and the method of assembling the piezoelectric bulb 1F- according to ICJ and Uniko's defense allows the sounding body to be reliably and easily fixed to the nodal point with adhesive. In other words, since the number of contact points is constant each month, it is possible to buy a piezoelectric bulb 1f of stable quality for one foot with economical advantages.

[Brief explanation of the drawing]

FIG. 1 shows the conventional method I: assembly (the piezoelectric buzzer is shown on the rim, so FIG. 1A is a back view, and FIG. Fig. 2 shows a method of assembling a piezoelectric block according to the present invention;
) is a rear view of the guide rib in the state where the piezoelectric bridge is pressed twice, and the cross-sectional view of the same figure ((n) is the same figure (1)).゛-12・・・・・・
...Emitting device 711 body 14...Piezoelectric element'
1G・・・・・・・・・i;lii jI(thin i anti-20
...... Case 20a... Large moon portion 20 b-,..., Ring-shaped protrusion 20C...jΔ
Hole 2 OL+...Central through hole 22...
...Garr Torino 2/I...Base 2
0・・・・・・・・・Adhesive agent special W

Claims (1)

[Claims] In a method of assembling a sounding body in which a piezoelectric element is auxiliary layered on an elastic thin plate in a dish-shaped case, a protrusion is provided on the inner surface of the bowl portion of the case in advance to abut against a nodal bolt of the sounding body that protrudes inwardly. A plurality of through holes passing through the ceiling are formed in the ring 6, the distance between the through holes is made substantially the same as the outer shape of the sounding body, and a hole is formed in each of the through holes. After inserting the guide rib, place the outer peripheral end of the sounding body on the inner surface of the guide rib, insert it into the case, and fix it on the protrusion. Removed from inside the hole-C
Zj method for assembling a piezoelectric tube If-.