Synchronous linear electric motor and method for determining the commutation offset of a linear drive with such a synchronous linear electric motor

US6054783A · kind A · utility

Assignee

• Rexroth Indramat GmbH · DE

Inventors

• Werner Philipp · Schorndorf, DE
• Eberhard Schemm · Lohr am Main, DE
• Bernd Schnurr · Lohr am Main, DE

Key dates

• Filing date: Jun 10, 1998
• Grant date: Apr 25, 2000
• Expiry date: Jun 10, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B23Q17/22
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A synchronous linear electric motor with a secondary part that contains several permanent magnets arranged in a certain pole grid, and with a primary part that can move relative to the secondary part and whose position relative to the secondary part can be determined by a travel measurement system. For a simple determination of a commutation offset during startup of the linear motor, a mechanical marking is provided on the secondary part that has a known relationship to the pole grid of the permanent magnets. There is also a method for detecting the commutation.