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. 02, 1991
Filed:
Jul. 23, 1990
Applicant:
Inventors:
Raymond J Chaney, Berkeley, GB;
David R McMurtry, Wotton-Under-Edge, GB;
David Wilson, Stonehouse, GB;
Assignee:
Renishaw plc, Gloucestershire, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
32420722 ;
Abstract
A scale is fixed to one part of a position determining apparatus, and a read head is relatively movable on the other part of the apparatus. Incremental scale marks are regularly spaced along the scale and are counted in a counter to give an indication of relative position of the scale and read head. The marks may for example be recorded magnetically. Some scales are distinguishable from the other, e.g., by having different amplitudes. Positioning information can then be encoded in a binary word. This can either be absolute position values, or error correction information.