JPS6312637Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the structure of a piezoelectric sounding body in which a piezoelectric buzzer element, which has a structure in which a thin piezoelectric ceramic plate is bonded to a diaphragm made of a thin metal plate, is housed in a case. The aim is to provide a product with a simple structure, easy to use, and low cost.

A piezoelectric buzzer element generates sound by converting the expansion and contraction of a piezoelectric ceramic plate into deflection vibration when an alternating current electric field is applied to the piezoelectric ceramic plate, together with a diaphragm made of metal plates bonded together. In order to produce sound efficiently, it is necessary to support or fix the piezoelectric buzzer element by appropriate means. A commonly used structure is one in which the outer edge of the diaphragm of a piezoelectric buzzer element is fixed around the periphery. Traditional structure first
This will be explained based on the figure and FIG. Reference numeral 1 denotes a lower case having a sound emitting hole 2 on the bottom and a step 3 around the periphery, and is made of plastic or the like. 4 is a piezoelectric buzzer element in which a thin piezoelectric ceramic plate 6 is bonded to a thin diaphragm 5 such as a metal plate, and lead wires 7 are electrically connected to both electrodes of the piezoelectric ceramic plate 6. One side of this lead wire 7 is often connected directly to the electrode of the piezoelectric ceramic plate 6, and the other side is electrically and mechanically connected through the diaphragm 5. Generally, the lead wire 7 is connected by soldering. In this embodiment, there are two lead wires, but in some cases, partial electrodes may be provided on the electrodes of the piezoelectric ceramic plate 6, and three lead wires may be used for a self-oscillation circuit. 8 is an upper case made of plastic or the like that has a convex part 9 and is made to fit well with the lower case 1; The outer periphery of the diaphragm 5 of the buzzer element 4 is sandwiched and fixed.
An adhesive such as epoxy resin is mainly used for this fixing. In this way, a piezoelectric sounding body is produced, and if this sounding body is to have a terminal structure, the terminal is attached to the upper case 8, and the lead wires 7 are connected internally by soldering or the like to form the terminal structure.

This type of sounding body is a common structure, but the assembly process takes time because adhesive is used, assembly jigs and tools are required, and the terminal structure requires mounting on the upper case. It has been difficult to reduce costs, such as the installation of terminals and the need for four or more connection points in the internal wiring, making it difficult to achieve significant cost reductions.

The present invention was devised to eliminate the above-mentioned drawbacks of the conventional piezoelectric sounding body, and proposes a piezoelectric sounding body that enables a significant cost reduction.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. In the figure, reference numeral 10 denotes a lower case having a sound emitting hole 11 provided on the bottom surface and a stepped portion 12 provided around the periphery, and is made of plastic or the like. 13 is a piezoelectric buzzer element constructed by bonding a thin piezoelectric ceramic plate 15 to a diaphragm 14 made of a thin metal plate having a larger area. Reference numeral 16 designates an upper case made of plastic or the like with a hollowed-out central portion, and its periphery is designed to fit well with the stepped portion 12 of the lower case 10. 1
7 and 17' are clips made of a metal plate made of a springy material, and the holding piece 1 is formed in a U-shape.
The outer edge of the diaphragm 14 constituting the piezoelectric buzzer element 13 is sandwiched between the upper case 16 and the lower case 10 by 8, 18' and 19, 19', and both cases 1
0 and 16 are fixed together while being pressurized by their spring properties. On the other hand, the above clip 17,1
External terminal pins 20, 20' and internal connection terminals 21, 21' are integrally provided at 7' in a structure extending outward and inward from both cases 10, 16. Internal connection terminals 21 and 21' of the clips 17 and 17' are electrically connected to the electrode surface of the piezoelectric ceramic plate 15 and the diaphragm 14, respectively. Here, the connection points can be made by contact only or by soldering.

The present invention is constructed as described above, and there is no need for adhesive when manufacturing a piezoelectric sounding element, and the clip can be used to connect external connection terminals, internal connection terminals,
It has a versatile function of fixing the upper and lower cases and fixing the outer periphery of the piezoelectric buzzer element, and has a simple structure.
This enables significant cost reductions.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional piezoelectric sounding element, Fig. 2 is an exploded perspective view of the same, Fig. 3 is a sectional view showing an embodiment of the piezoelectric sounding element according to the present invention, and Fig. 4 is an exploded perspective view of the same. It is. 10... lower case, 13... piezoelectric buzzer element,
14... Vibration plate, 15... Piezoelectric ceramic plate, 16...
Upper case, 17, 17'...Clip, 20, 2
0'...External connection terminal (external terminal pin), 21,
21'...Internal connection terminal (terminal for internal connection).

Claims (1)

[Scope of utility model registration request] A piezoelectric buzzer element made by bonding a piezoelectric ceramic plate to a diaphragm made of a metal plate with a larger area, upper and lower cases that hold the outer edge of this piezoelectric buzzer element, and crimped upper and lower cases, respectively. the clip has a U-shaped holding piece that applies pressure in the direction of A piezoelectric sounding body featuring