Patent · US Expired

Scanning unit for an optical position measuring system

US6198534A · kind A · utility

25Cited by

6References

29Claims

0Family size

Assignee

JOHANNES HEIDENHAIN GmbH · DE

Inventors

Volker Hofer · Traunreut, DE
Wolfgang Holzapfel · Obing, DE
Walter Huber · Traunstein, DE
Elmar Mayer · Nußdorf, DE

Key dates

Filing date	Aug 7, 1998
Grant date	Mar 6, 2001
Priority date	—
Expiry date	Aug 7, 2018

Classification

Technology area (CPC G)Physics
CPC primaryG01D5/2457
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

A scanning unit for an optical position measuring system is disclosed which, besides periodic incremental signals, also provides at least one reference pulse signal at a defined reference position of a scale and a scanning unit which is movable relative to it. For scanning a reference mark on the scale, the scanning unit comprises a scanning plate with at least one reference mark scanning field and/or at least one reference pulse detector element. A filtering effect results either from the design of the reference mark scanning field or by the design of one or several reference mark detector elements in such a way that the periodic incremental signal portion of the reference pulse signal next to the reference position can be eliminated to a great extent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.