Coded disc for an optoelectronic displacement or angle measuring device

US6888126B2 · kind B2 · utility

Assignee

• Leopold KOSTAL GmbH & Co. KG · DE

Inventors

• Frank Blasing · Werl, DE
• Ralph Böbel · Dortmund, DE

Key dates

• Filing date: Feb 14, 2001
• Grant date: May 3, 2005
• Expiry date: Nov 3, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/34776
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An optoelectronic position measuring device includes an encoder disk having a coding with a digital code and an analog coded track. The analog track includes segments which are in a series and whose width changes. An illuminator images the coding onto a sensor having transducers. The sensor determines the width of the analog track at a given position of the disk relative to the sensor as a function of the number of transducers upon which the analog track is optically imaged onto. The analog track is part of a continuous reference code track which has central symmetry in which the segments have a code length corresponding to the smallest resolution step of the digital coding. The layout of the segments and the resolving power of the sensor are matched such that movement of the disk along the code length is resolvable into at least two defined steps.