Stretched piezopolymer transducer with unsupported areas

US4558249A · kind A · utility

Inventors

• Reinhard Lerch · Heroldsberg, DE
• Gerhard Sessler · Summit, US

Key dates

• Filing date: Mar 12, 1984
• Grant date: Dec 10, 1985
• Expiry date: Mar 12, 2004

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S310/80
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

In the disclosed transducer, a frame supports the edges of a piezopolymer sheet coated on both faces with electrodes, while a holding structure supports an area but leaves a larger area of the central portion of the sheet unsupported. According to preferred embodiments, the frame stretches the sheet, in the form of a membrane, across one or more contact areas on the holding structure, and the contact area approximates a point located near the center of the sheet or a number of concentric annuli. Preferably, the structure forms one terminal contacting one electrode and the frame forms another terminal contacting the other electrode.