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. 27, 2002
Filed:
Aug. 20, 1999
Staffan Jonsson, Karlskoga, SE;
MKS Instruments, Andover, MD (US);
Abstract
A pressure sensor of substantially ceramic material comprises a rigid housing having a thick base plate, an interior shielding plate, and a movable diaphragm. A cavity providing a reference pressure is formed between the shielding plate and the diaphragm and on the opposite walls thereof are electrodes, which form a capacitor, the capacity of which is sensed. A temperature sensor comprises thermistors positioned inside the housing, between the base plate and the shielding plate, with the reference resistors on the surface of the base plate facing outwards. The shielding plate is thin, so that the thermistors are located near the diaphragm and are sensitive to the temperature thereof. Therefore the temperature sensor element has minimum influence on the electric properties of the pressure sensor and in particular on the mechanical properties of the diaphragm.