Originally Published MPMN April 2005

HOTLINE

High Resolution Servomotor Offers Feedback in a 36-mm Package

The unit provides high performance for small-frame servos

Susan Wallace

A new rotary encoder is more than a smaller version of a conventional rotary encoder. The SKS 36 SinCos motor feedback system with a Hiperface interface has a fundamentally different construction. The unit from Sick Stegmann Inc. (Dayton, OH) has a minimum number of components, allowing the production of truly miniaturized rotary encoders. This allows small motors manufacturers to considerably shorten the overall length of their devices.

The product features the Mini-Disc (MiDi) technology. The very small code disk includes a track radius of 2 mm, which permits integral scanning of the entire code disk. This eliminates eccentricity errors of the code disk, ball bearings, and shaft common to conventional systems. The code disk is mounted in the center of the axis of rotation, so high angular velocities are no longer limited by it.

The 128 code disk lines are integrally scanned using a specially developed Opto-ASIC. The resulting sinusoidal signals have a high linearity and interpolation capability. In spite of its small dimensions, the SKS 36 encoder features 12-bit self-monitoring absolute position capabilities for maximum reliability and accuracy. An error in the absolute information can be determined before a shaft movement even takes place. In the event of an erroneous code, an error message is produced.

Sick Stegmann Inc.
7496 Webster St.
Dayton, OH 45414
P: 800/811-9110
F: 937/454-1955
www.stegmann.com



Copyright ©2005 Medical Product Manufacturing News