The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 09, 2001
Filed:
Mar. 09, 1999
Lennart Stridsberg, Enskede, SE;
Stridsberg Innovation AB, Enskede, SE;
Abstract
An encoder disc (,) of an optical position transducer is mounted on a short protruding part (,) of a rotor (,) of an electric motor close to torque creating parts. One part of the optical system, normally the light emitter part (,), is insertable between the rotor (,) and the encoder disc (,) after the insertion of the rotor-encoder disc assembly into the motor stator case (,). The optical incremental encoder signals are fed both to a moderate frequency digital counter that counts 4 counts per basic encoder period and to an A/D-converter that samples and digitises the primary encoder analog signals. A synchronising network ensures that the primary encoder digitised signal corresponds to the correct state of the digital counter. More than one decoder head can be used to compensate for the bearing play common in servo motors having varying axial loads. This construction gives a high speed resolution and fast speed response, is very compact and operates with modest demands on bearing precision.