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:
Nov. 23, 2010
Filed:
Nov. 13, 2006
Colin Keith Howley, Stonehouse, GB;
Colin Keith Howley, Stonehouse, GB;
Renishaw PLC, Wotton-under-Edge, GB;
Abstract
A scale reading apparatus includes a readhead that is moveable relative to a scale. The readhead includes an incremental channel from which a series of reference mark pulses are produced as the readhead is moved relative to the scale. A reference mark channel is also provided that produce a reference mark gating pulse when the readhead passes a predetermined (absolute) position mark on the scale. An alignment detection unit monitors during use, phase alignment of the reference mark gating pulse and reference mark pulses. The alignment detection unit is arranged to monitor the phase of the leading and trailing edges of said reference mark gating pulse relative to the phase of the reference mark pulses. The apparatus may be used in position encoders and the like.