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:
May. 05, 1992
Filed:
Mar. 12, 1991
Harald Bernard, Waldkraiburg, DE;
Alfons Spies, Seebruck, DE;
Dr. Johannes Heidenhain GmbH, Traunreut, DE;
Abstract
The angular graduation of a graduated disk is scanned in a measuring device by a scanning unit by the movement of light beams in two angular graduation areas located diametrically opposite each other. To compensate for wobble errors caused by the wobbling of the graduated disk, the light beam emanating from a light source impinges on the graduated disk at a point outside of the angular graduation and, following reflection and deflection by a triple prism, impinges parallel to itself in the form of a light beam on an impact point in a first the graduation area. The light beam is split into two diffraction beams by the graduation, and meet, after having passed through a deflection prism, at a meeting point in a second angular graduation area. Since the impact point and the meeting point are always located on the same radius, the wobbling of the disk does not have a disadvantageous effect on the accuracy of measurement.