EP0051832A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Piezoelectric ceramic transducer
Assignee: Hitachi Ltd
•
Filing: 1981-10-29
•
Granted: —
•
Expires: 2001-10-29
Abstract
Abstract An electro-acoustical transducer includes a piezoelectric ceramic plate (11) which has curved surfaces, electrodes (12) formed on both main surfaces of the plate (11), a frame (15) of an organic high-polymer resin for holding the plate (11), and means for applying an electric signal to the electrodes (12). Since the piezoelectric ceramic plate (11) has curved surfaces and the holding frame (15) is made of an organic high-polymer resin, the transducer is suitable as a loudspeaker or as a microphone having a wide frequency band.
Inventors
- 👤 Akio Kumada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 16:16
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/04; H04R17/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
54 words
A transducer including at least a piezoelectric ceramic plate (11) which has curved surfaces, electrodes (12) formed on both main surfaces of the plate, a frame (15) which holds the plate, and means for applying an electric signal to the electrodes, characterized in that the holding frame is made of an organic high-polymer resin.
Claim 2
Dependent Claim
54 words
A transducer including at least a piezoelectric ceramic plate (11) which has curved surfaces, electrodes (12) formed on both main surfaces of the plate, a frame (15) which holds the plate, and means for applying an electric signal to the electrodes, characterized in that the holding frame is made of an organic high-polymer resin.
Claim 3
Dependent Claim
32 words
The transducer of claim 1, characterized in that the holding frame (15) is in the shape of a flat plate which has an opening (14) or a recess in its central part.
Claim 4
Dependent Claim
22 words
The transducer of claim 1 or 2, characterized in that the piezoelectric ceramic plate (11) is made of a transparent ceramic meterial.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.