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:
Mar. 19, 2002
Filed:
May. 17, 1999
Microwave sensor for determining position for displacement of a movable part, such as a valve needle
Heinz Pfizenmaier, Leonberg, DE;
Klaus Voigtlaender, Wangen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The microwave sensor produces an electrical output signal according to a position or displacement of a movable mechanical part ( ), especially a valve needle in an injector valve for injecting fuel into an internal combustion engine. This position or displacement sensor includes a cavity resonator ( ) provided with walls bounding a cavity ( ) dimensioned for microwaves of a predetermined frequency and an antenna ( ) for reception of the microwaves in the cavity. The end ( ) of the movable mechanical part ( ) protrudes into the cavity. A hybrid evaluating circuit ( ) is connected with the antenna, which detects changes in the microwave radiation fed into and coupled out of the cavity, e.g. phase relationships, which depend on the position of the mechanical part ( ), so that small position changes in very tight spaces are accurately determined.