Position measuring device

US7057161B2 · kind B2 · utility

Assignee

• DR. JOHANNES HEIDENHAIN GMBH · DE

Inventors

• Alexander Gruber · St. Georgen, DE
• Michael Hermann · Tacherting, DE
• Wolfgang Holzapfel · Obing, DE
• Markus Kühler · Traunreut, DE
• Herbert Pronold · Traunreut, DE
• Sebastian Tondorf · Waging am See, DE

Key dates

• Filing date: Jul 5, 2002
• Grant date: Jun 6, 2006
• Expiry date: Aug 27, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/38
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A position measuring device having a scanning device and a scale, wherein the scanning device is movable in relation to the scale in a measuring direction. The scale including a measuring graduation, wherein periodic measuring signals are generated when the scanning device scans the measuring graduation and a reference marking, wherein a reference marking signal is generated when the scanning device scans the reference marking with a scanning beam bundle. The scale further includes a first optically scannable area marking next to the reference marking and a second optically scannable area marking next to the reference marking and which has a different optical deflection property than the first optically scannable area marking, wherein photoelectric scanning of the first and second optically scannable area markings with the scanning beam bundle from the scanning device generates an area signal that differentiates characteristics of the first and second optically scannable area markings. A first photo-receiver receives light from the first optically scannable area marking and a second photo-receiver receives light from the second optically scannable area marking.