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. 16, 1989
Filed:
May. 06, 1988
Jean-Pascal Valentin, Pouilley-les-Vignes, FR;
Pierre Maitre, Besancon, FR;
Fischer & Porter Company, Warminster, PA (US);
Abstract
A differential pressure transducer of the capacitive type responsive to fluid pressure. The transducer includes a cylindrical body having insulating sections at either end provided with a planar end face and a concave cavity surrounded by an annular rim. The cavities communicate with each other through an internal duct in the body and are filled with a dielectric fluid. Covering each cavity and sealed to the surrounding rim is a diaphragm provided with a movable electrode which cooperates with a fixed electrode on the cavity surface to form a capacitor therewith whose value varies as a function of diaphragm deflection in response to an applied pressure. The contour of each cavity is defined by an inner concave portion whose center is aligned with the longitudinal axis of the body and whose periphery merges with an inflection zone, and an outer portion which curves from the inflection zone toward the rim to merge tangentially therewith to avoid a sharp angle at the inner edge of the rim, the inflection zone being about half the distance from the center to the rim.