Linear encoder and method of adjusting a gap between a sensor unit and a scale of the linear encoder

Patent metadata

Field	Value
Publication number	US-9395215-B2
Application number	US-201414219093-A
Country	US
Kind code	B2
Filing date	Mar 19, 2014
Priority date	Mar 21, 2013
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

A linear encoder includes a housing, a scale disposed within the housing and a sensor unit disposed within the housing facing the scale with a gap between the sensor unit and the scale. The sensor unit is configured to scan the scale and obtain position information. At least one adjustment hole for a gap adjustment is disposed in at least one of the housing and an end cover of the housing at a position corresponding to a position of the gap.

First claim

What is claimed is:

1. A linear encoder, comprising:
a housing;
a scale disposed within the housing;
a sensor unit disposed within the housing facing the scale with a gap between the sensor unit and the scale, the sensor unit being configured to scan the scale and obtain position information;
at least one adjustment hole for a gap adjustment disposed in at least one of the housing and an end cover of the housing at a position corresponding to a position of the gap; and
a removable cover on the at least one adjustment hole,
wherein the at least one adjustment hole is configured such that a gap gauge is insertable into the gap between the scale and the sensor unit through the at least one adjustment hole when the cover is removed.

2. The linear encoder according to claim 1 , wherein the scale and the sensor unit do not contact one another.

3. The linear encoder according to claim 2 , wherein the sensor unit is not guided on the scale and is not guided on the housing.

4. The linear encoder according to claim 1 , wherein the at least one adjustment hole comprises a plurality of adjustment holes disposed in the housing one after another in a measuring direction.

5. The linear encoder according to claim 4 , wherein the at least one adjustment hole includes a first adjustment hole arranged in a vicinity of a first end portion of the housing and a second adjustment hole arranged in a vicinity of a second end portion of the housing.

6. The linear encoder according to claim 1 , wherein the at least one adjustment hole is disposed in a front side of the housing and the scale is orientated so that the gap gauge is insertable through the at least one adjustment hole in a direction corresponding to a direction of holes that are disposed in the housing for screwing the housing on a device.

7. A method of adjusting a linear encoder comprising a housing, a scale disposed within the housing, a sensor unit disposed within the housing facing the scale with a gap between the sensor unit and the scale, the sensor unit being configured to scan the scale and obtain position information, and at least one adjustment hole for a gap adjustment disposed in at least one of the housing and an end cover of the housing at a position corresponding to a position of the gap, the method comprising:
removing a cover installed on the at least one adjustment hole so as to expose the at least one adjustment hole;
inserting a gap gauge between the scale and the sensor unit through the at least one adjustment hole;
adjusting a position of the sensor unit so as to adjust the gap between the sensor unit and the scale; and
removing the gap gauge and re-installing the cover.

Assignees

• Heidenhain Gmbh Dr Johannes

Inventors

• Motoyuki Katsumi

Classifications

• G01D5/24433

  by mechanical means · CPC title

• G01D5/34738

  Axles; Driving or coupling means · CPC title

• G01D5/34746 Primary

  Linear encoders · CPC title

• G01D5/24423 Primary

  Mounting means or means for restraining during shipping (G01D5/24442 takes precedence) · CPC title