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:
Aug. 25, 1998
Filed:
Oct. 24, 1996
Philip C Harwood, Elgin, IL (US);
Dukane Corporation, St. Charles, IL (US);
Abstract
A pre-stressed, sandwich-type, ultrasonic transducer assembly includes front and rear mass members having stacked therebetween alternating piezoelectric members and electrode members, with each of the members having surfaces which are substantially flat except for minute surface irregularities. Thin, soft, aluminum foil washers are respectively disposed between the facing surfaces of adjacent members of the stack. At least one bolt joins the front and rear mass members to subject it to a compressive pre-load, under which load the washers deform to follow the surface irregularities of the adjacent member surfaces and thereby fill inter-element voids created by such irregularities.