Two Encoders are Better than One

Originally Published MPMN Web Exclusive July 2008

BREAKTHROUGHS

Two Encoders are Better than One

Dual functionality in one compact package is a product feature that tends to get a design engineer’s attention. Elma Electronic Inc. (Fremont, CA; www.elma.com), a designer and manufacturer of rotary components and electronic packaging products, has unveiled a product catering to this demand.

Designed with a dual concentric inner shaft and outer pole, the Type E37 product features two encoders in one switch. Incorporation of the switch into medical instruments or diagnostic devices could enable OEMs to cut costs and save space that would have otherwise been allotted to a second, separate switch.

While dual concentric switches do exist on the market, the Type E37 boasts a construction that is significantly more rugged than that of competing products, according to Elma. The use of gold contacts, coupled with the metal-based housing and shaft, reinforce this claim.

“The Elma switches, with the ‘click with a kick,’ allow a user to use a medical instrument and not necessarily have to look at the instrument when turning the dial,” says Justin Moll, director of marketing for Elma. “With the ‘indexing feedback’ you get from the encoder, you can feel how many positions you have turned the dial.” The indexing has a switching torque of 0.5, 1.5, 2.0, or 2.5 N•cm that is consistent over the life of the encoder, according to Elma.

The product operates within a temperature range of –40°–85°C and is available with 16 or 32 detents in standard resolution. It comes either with or without an integrated push button and has optional IP68 front-panel sealing. Additional features include a threaded or nonthreaded bushing, vertical or horizontal mounting, and different options for shaft dimension and shapes.

Copyright ©2008 Medical Product Manufacturing News