The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 07, 1992
Filed:
Jun. 22, 1990
Thomas Uhl, Selb, DE;
Herbert Frisch, Vienna, AT;
Hoechst CeramTec Aktiengesellschaft, Selb, DE;
Hoerbiger Fluidtechnik KG, Vienna, AT;
Abstract
A piezoelectric bending transducer is described which is suitable for installation in a valve channel. It is composed of at least one ceramic layer which is metalized on both sides and has piezoelectric properties and which is polarized such that on application of a voltage it undergoes a change in length, and of at least one rigid molding which is joined to the whole surface thereof and has approximately the same surface dimensions and which on application of a voltage does not undergo an elongation or undergoes an opposite elongation. The piezoceramic layer contains an unmetallized area which has a roughness R.sub.a of less the 0.5 .mu.m and covers an orifice in the valve channel.