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:
Apr. 07, 1981
Filed:
Mar. 28, 1979
Friedrich R Hertrich, Boulder, CO (US);
Digital Equipment Corporation, Maynard, MA (US);
Abstract
A velocity transducer for converting linear mechanical motion to an electrical signal. A stationary permanent magnet is supported within and spaced from an iron pole piece assembly which forms a closed path around the magnet. The pole piece assembly has a pair of linear pole piece segments which extend in parallel on opposite sides of the magnet, spaced apart from the north and south pole faces of the magnet, respectively. A moveable (i.e. slideable) coil is wound around each such linear pole piece. The two coils are series-connected and oppositely wound with respect to the flux produced by the magnet. Noise signals induced in the coils subtract from each other and substantially cancel, but motion-related signals add.