Custom Magnetic Encoder Solves Problem for Printing Equipment Manufacturer

A major printing equipment manufacturer needed to accurately measure the angular position of the imaging drum in a sophisticated offset plate setter. A traditional optical encoder used in the past produced cyclical errors due to the flexible coupling which resulted in poor image quality. A new custom magnetoresistive encoder, designed and produced by Admotec Inc., was able to mount directly to the imaging drum, eliminating the coupling and its error. As a result, the accuracy was greatly improved, set-up and adjustment times were reduced, and higher quality printing plates were produced at lower cost.

The custom magnetoresistive encoder consists of a 260mm solid aluminum encoder wheel with 1800 magnetic poles and a sensor board incorporating a chip-on-board interpolator to increase resolution by a factor of 4. This custom encoder is a modification of the standard Admotec EK600 Series magnetic encoder.