JPH0413916Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a piezoelectric vibrator using a piezoelectric diaphragm, and particularly relates to a piezoelectric vibrator used in electroacoustic transducers such as speakers and microphones.

[Conventional technology]

A conventional piezoelectric vibrator is formed by providing membrane electrodes on both sides of a ceramic membrane piezoelectric material.

[Problem that the invention attempts to solve]

However, in the above conventional example, when used as an electroacoustic device, due to the high Q of the piezoelectric diaphragm, a sharp peak at the resonance point is followed by an uneven response due to parasitic vibration, which increases harmonic distortion and deteriorates sound quality. At the same time, there was a problem in that the sound pressure level decreased in the mid to low frequency range.

[Summary of the idea]

In order to solve the above-mentioned problems, the piezoelectric vibrator of the present invention is made by pasting a mixture 4 of metal powder 2 and adhesive 3 to the center of a piezoelectric diaphragm 1 as shown in the figure.

With such a configuration, the piezoelectric diaphragm 1
Q is suppressed in the kneaded material 4 at the center of the kneaded material 4, and the vibration mode is improved.

[Specific explanation of the idea]

Embodiments of the present invention will be described below with reference to the drawings.

The drawing is a sectional view showing one embodiment of the piezoelectric vibrator of the present invention, and 1 is a piezoelectric diaphragm. This piezoelectric diaphragm 1
For example, two ceramic piezoelectric membranes 5 are bonded together, membrane electrodes 6a, 6b are formed on the bonded surface and both outer surfaces, and these electrodes 6a,
It is of a laminated type in which lead wires 7a and 7b are connected to 6b. This laminated piezoelectric diaphragm 1 is preferable because it can have a large electrostrictive effect, but a single-layer type piezoelectric diaphragm 1 is preferable because it can have a large electrostrictive effect, but a single-layer type piezoelectric diaphragm 1 is a single-layer type in which film-like electrodes are formed on both sides of a ceramic-based film-like piezoelectric material and lead wires are connected to these electrodes. It can also be from. A kneaded material 4 of metal powder 2 and adhesive 3 is adhered to the center of both sides of this laminated piezoelectric diaphragm 1 .

Metal powder 2 is a metal powder with a density of 8 or more, such as copper,
Powder of lead, iron, brass, etc. can be used.

As the adhesive 3, epoxy-based, polyester-based, acrylic-based, vinyl acetate-based, rubber-based adhesives, etc. can be used.

When the piezoelectric vibrator of the present invention having such a structure is used, for example, as a speaker, when an audio signal is input between the electrodes 6a and 6b via the lead wires 7a and 7b, the piezoelectric vibrator 1 vibrates and reproduces the sound. be able to. Since the kneaded material 4 is attached to the center of both sides of the piezoelectric diaphragm 1, Q is suppressed and the vibration mode is improved. Therefore, parasitic vibrations are no longer generated, high-frequency distortion is eliminated, sound quality can be improved, and the sound pressure level in the mid-to-low range can be increased.

In this case, the vibration mode can be optimized by adjusting the amount of metal powder 2 in the kneaded material 4 depending on the size of the piezoelectric diaphragm 1.

As described above, according to the present invention, the kneaded material 4 of the metal powder 2 and the adhesive 3 is adhered to the center of the piezoelectric diaphragm 1, so that the kneaded material 4 in the center of the piezoelectric diaphragm 1 has a Q is suppressed and the vibration mode is improved, so parasitic vibrations no longer occur, high frequency distortion can be eliminated, sound quality can be improved, and the sound pressure level in the mid-low range can be increased.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the piezoelectric vibrator of the present invention. 1...Piezoelectric diaphragm, 2...Metal powder, 3...Adhesive, 4...Kneaded material.

Claims (1)

[Scope of utility model registration request] A piezoelectric vibrator is made by pasting a mixture of metal powder and adhesive onto the center of a piezoelectric diaphragm.