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:
May. 29, 1990
Filed:
Jul. 31, 1989
Lawrence R Poglitsch, Mt. Prospect, IL (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
A method for oil filling an internal pressure sensor cavity (20) is disclosed which minimizes manufacturing process time and insures totally and properly filling the internal cavity with oil. A predetermined amount of oil (23) is added to a pressure sensor external cavity (21) connected through an opening (22) to an internal sensor cavity (20) having a sensing element (17) therein. A vacuum is drawn while the oil is in the external cavity thus providing at least a partial vacuum in at least the internal cavity. Then vacuum pressure is released causing the oil to be drawn into the internal cavity through the opening. Subsequently a sealing means (27) is force fit in the opening to seal the internal cavity.