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. 19, 1982
Filed:
Jul. 05, 1979
Applicant:
Inventor:
John M Reynard, Framingham, MA (US);
Assignee:
Polaroid Corporation, Cambridge, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
1791 / ; 1791 / ;
Abstract
The desired groove shape in a backplate of a combination transmitting and receiving, capacitance type, electrostatic transducer are more consistently reproduceable in a die forming operation by utilizing an open ended grooved configuration so that groove shape deforming lubricating fluid, necessary in said die forming operation, and air, can escape from between the die tool and the transducer backplate through said open ended grooves as said grooves are die formed on said backplate.