New range of sensorless brushless DC (SBLDC) gearmotors

Paul Boughton
In response to OEMs seeking higher energy efficiency and power density as well as simpler assembly and increased design life for their equipment, Bison Gear & Engineering Corp is introducing a new line of sensorless brushless DC (SBLDC) parallel-shaft gearmotors with powers up to 124W (1/6HP). The new 34 frame Autonomotor gearmotors are powered by totally enclosed, non-ventilated (TENV) brushless motors that are sensorless to reduce cost, size and wiring complexity while offering improved reliability and noise immunity compared to brushless motors with shaft-mounted rotor position sensors.
Employing modern DSP technology that facilitates the implementation of sensorless control algorithms and eliminates the need for position sensors (and associated wiring) required in conventional BLDC motor-control systems, Bison's new low-voltage Autonomotor gearmotors are offered in eleven standard versions with gear ratios from 5:1 to 215.6:1 and rated output speeds from 470 to 11rpm with a 10:1 speed range. Speed can be adjusted with either a supplied potentiometer or a 0-5V DC signal. Continuous output torques range from 2.1 to 33.9Nm (19 to 300 in-lbs). The gearmotors employ all-steel gearing and oil bath lubrication for long operating lifetimes.
Suitable for factory automation, packaging equipment, foodservice equipment, alternative energy systems, stationary agricultural equipment and other machinery, the Autonomotor gearmotors are part of Bison Gear's comprehensive In-Stock, Instant-Ship (ISIS) programme that supports Bison's distribution partners and offers same-day shipment.
Matt Hanson, vice president of portfolio management at Bison Gear, states: "The National Science Foundation grant awarded to Bison in 2005 for research on higher efficiency electric motors paved the way for this innovative new brushless DC development. With this being Bison's 50th anniversary year, we are proud to introduce the Autonomotor sensorless brushless development as the second offering in the exciting line-up of new products coming from Bison in 2010."
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