Absolute measuring length measuring system

Patent metadata

Field	Value
Publication number	US-9976878-B2
Application number	US-201615387960-A
Country	US
Kind code	B2
Filing date	Dec 22, 2016
Priority date	Dec 23, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

In a length or position measuring system which has an at least locally substantially linear measuring gauge and at least one sensor to be moved relative to the measuring gauge, wherein the measuring gauge includes an incremental track and at least one absolute track and wherein the incremental track and the at least one absolute track have poles arranged in the longitudinal direction of the measuring gauge, the poles of the at least one absolute track form at least two regions in the sensor with different field strengths or signal amplitudes.

First claim

What is claimed is:

1. A length or position measuring device which has an at least locally substantially linear measuring gauge and at least one sensor to be moved relative to the measuring gauge,
wherein the measuring gauge comprises an incremental track and at least one absolute track,
wherein the incremental track and the at least one absolute track have poles arranged in the longitudinal direction of the measuring gauge,
wherein the poles of the at least one absolute track are divided into at least four segments,
wherein logical values of pole pairs provided by the absolute track are formed from at least completely opposed, over partially opposed, over neutral, over partially concordant, and completely concordant compared to the corresponding pole pairs of the incremental track, thus providing at least five logical values +1, +0.5, 0, −0.5, and −1, and
wherein the at least one absolute track provides a mixture of poles of different polarity or of different magnetization such that the at least five logical values are generated.

2. The length or position measuring device according to claim 1 , wherein the absolute track is divided into at least sixteen segments,
wherein the logical values provided by the absolute track vary between a positive value and a negative value, and
wherein at least three intermediate steps with logical values between them are formed.

3. The length or position measuring device according to claim 1 , wherein m n poles are able to be detected by n sensors and by m quantization steps.

4. The length or position measuring device according to claim 1 , wherein a conversion of the signal amplitude arising in the absolute track for each pole pair in terms of a mean of zero is around +/−0.01 tesla with a 100% magnetization via around +/−0.005 tesla to zero and then again in opposition in phase at around +/−0.01 tesla.

5. The length or position measuring device according to claim 4 , wherein the conversion of the signal amplitude at a distance of 6 mm from the measuring gauge in terms of the mean of zero is about +/−0.007 tesla with a 100% magnetization via about +/−0.004 tesla to zero and then again in phase opposition at around +/−0.007 tesla.

Assignees

• Balluff Gmbh
• Ballufff GmbH

Inventors

• Burkhardt Thomas
• Zern Achim

Classifications

• G01D5/14

  influencing the magnitude of a current or voltage · CPC title

• G01D5/2497 Primary

  Absolute encoders (G01D5/2454 takes precedence) · CPC title

• G01D5/2455 Primary

  with incremental and absolute tracks on the same encoder · CPC title

• G01D5/2495

  Pseudo-random code · CPC title