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:
Sep. 13, 2005
Filed:
Jan. 30, 2004
Walter Huber, Traunstein, DE;
Udo Linnemann, Traunreut, DE;
Wolfgang Holzapfel, Obing, DE;
Dr. Johannes Heidenhain GmbH, Traunreut, DE;
Abstract
A position measuring system that includes a scale having an incremental graduation track of a defined incremental graduation period and on at least one defined reference position, a reference marking field with a mean reference marking graduation period. A scanning unit movable with respect to the scale, the scanning unit having a plurality of scanning elements for generating scanning signals, wherein at least two phase-shifted incremental signals are generated as scanning signals. A first evaluation device that determines a rough reference position. A second evaluation device that determines a beat signal phase. A third evaluation device, which is suitable for unequivocally marking a beat signal period from the rough reference position and, if a defined phase position exists, to issue a fine reference position from the beat signal phase.