JPS6145680Y2 - - Google Patents

Description

[Detailed explanation of the invention] As a speaker bimorph, a piezoelectric bimorph in which a pair of piezoelectric element plates are attached to a center electrode made of metal foil is widely known. A small tongue-shaped ridge provided on the electrode is sandwiched between the electrode surfaces exposed on the outside of a pair of piezoelectric element plates attached to the front and back surfaces of the electrode, and connected to each electrode surface by soldering, etc. A pair of lead wires is connected to the base of the outer electrode, which has an elastic connecting piece, by a troublesome process such as soldering, and one lead wire in particular has an extremely thin center of micrometer scale. Since soldering must be applied directly to the electrodes, a high degree of skill is required and mass productivity is poor.

The present invention aims to provide a piezoelectric bimorph outer electrode that is easy to mass-produce and can be easily attached to a speaker frame.The embodiments shown in the drawings will be described below.

In FIG. 1, 1a and 1b are a pair of polarized piezoelectric element plates with metallized electrode surfaces (not shown) formed on both main surfaces, and 2 is a pair of piezoelectric element plates 1a and 1b formed on the front and back sides by a conventional method. 3 is the outer electrode of the present invention shown enlarged in FIG. At the same time, a pair of elongated protrusions 3 are provided on both sides of the base 31.
2a' and 32b' are made of a metal flat plate protruding through cuts C and C, and the protrusions 32a' and 32b' are bent rearward at an angle of 180° vertically, respectively, and the above-mentioned center electrode 2 A pair of piezoelectric element plates 1 affixed to
They function as contacts 32a, 32b that connect the pair of piezoelectric element plates 1a, 1b in parallel to the electrode surfaces opposite to the bonding surfaces of a, 1b by soldering S, S, etc.

Note that the center electrode 2 and the pair of piezoelectric element plates 1
The concentric small hole 2' drilled in the center of a and 1b and the communicating center hole h consisting of 1a' and 1b' facilitate positioning when laminating and pasting these three parts, and When the laminate is attached to the center of the bottom surface of a cone-shaped vibrating piece (not shown), riveting can be used instead of the conventional adhesive, but this can be omitted.

As described above, the outer electrode of the piezoelectric bimorph of the present invention has a terminal leg in the center of the base that corresponds to the terminal leg extending from the center electrode with a pair of piezoelectric element plates attached to the front and back surfaces, and A pair of elongated strips bent at an angle of 180° and used as contacts to be connected by soldering, etc. to the electrode surface opposite to the bonding surface of the pair of piezoelectric element plates bonded to the above-mentioned center electrode. Since the projecting pieces are formed along the terminal legs, the terminal legs of the center electrode and the outer electrode can be directly conductive parts, making it possible to mass-produce bimorphs by eliminating the need for lead wires that require a high level of skill for connection such as soldering. Since the pair of terminal legs 31 and 33 are formed on the same plane, the small holes h ₁ and h ₂ protruding from them allow the rivets to be attached to the inner wall of the frame (not shown). Furthermore, by arranging the small holes h ₁ and h ₂ on the same center line as the center hole h, assembly to the speaker can be automated.

Furthermore, in actual implementation, as shown in FIG.
A terminal leg 33 corresponding to the terminal leg 21 outwards from the terminal leg, and a pair of contacts 32a, 32b on both sides of the terminal leg.
A portion 3, which will become an outer electrode, is provided with extended elongated projecting pieces 32a' and 32b', and is provided in a protruding manner by a connecting piece j.
A pair of piezoelectric element plates 1 are provided on the front and back surfaces of the center electrode 2.
a, 1b, a pair of elongated protrusions 32a', 32 provided on both sides of the other terminal leg 33 are attached.
Fold b′ 180° upside down and contact 3 respectively.
Piezoelectric element plates 1a and 1 facing each other as 2a and 32b
After making contact with the electrode surface of b and making connections S, S by soldering, etc., the connection parts C ₁ , C ₁ ′ and C ₂ , between the connecting piece j and the center electrode 2 and the outer electrode 3 are connected. By cutting C ₂ ′, the piezoelectric bimorph shown in Figure 1 is completed, so the center electrode and outer electrode can be punched out simultaneously from a single piece of material, making it easier to assemble the outer electrode. This has the great effect of greatly reducing manufacturing costs.

[Brief explanation of the drawing]

FIG. 1A is a plan view of a piezoelectric bimorph using the outer electrode of the present invention, FIG. 1 is a plan view of the outer electrode of the piezoelectric bimorph of the present invention, FIG. 3 is a side view of FIG. It is a top view which shows a case. 1a, 1b...Pair of piezoelectric element plates, 2...Center electrode, 21...Terminal leg, 3...Outer electrode, 31...
...Base, 32a, 32b...Pair of contacts, 32
a', 32b'...a pair of projecting pieces, 33...terminal leg.

Claims (1)

[Scope of utility model registration request] A pair of piezoelectric element plates attached to both main surfaces of a center electrode with terminal legs extending from the outer circumferential surface are used as a pair of contacts connected to both electrode surfaces on the opposite side to the attached surfaces. A piezoelectric device characterized in that a pair of elongated protrusions are formed by bending upward and downward backwards at an angle of 180 degrees from above, respectively, and are formed along terminal legs provided at the base corresponding to the terminal legs of the center electrode. The outer electrode of type bimorph.