Servomotors give excellent linearity and efficiency

In a world that is demanding ever smaller designs, UK drives and controls specialist firm EMS is offering design engineers a miniature brushless DC servomotor which has a diameter of just 6mm.

The new 'Minimotor' 0620 is electronically commutated and has even better dynamic characteristics and effective output power than the firm's brush commutated DC micromotors. With rotor inertia of only 0.0095g/cm2, the Minimotor achieves a continuous torque of 0.33mNm. The companion drive electronics required for operating the motor allows the no-load speed to be as high as 50,500 rpm. Despite its high performance, EMS' sales and marketing manager Jeff Mead told Eureka that the motor has "an especially long service life." The speed is regulated by a two-quadrant PWM servo amplifier of the series BLD 2401, which features outstanding linearity and excellent efficiency (90%). The speed control can be pre-selected using jumpers. Speed regulation and current limiting can be independently adjusted using two potentiometers. Matching planetary gearheads are available with a 6mm diameter and give reduction ratios from 4:1 up to 4,096:1. Applications include precision medical instruments, optical instrumentation, security and inspection systems and micro-actuators. DP Pointers * The brushless DC servomotors are just 6mm in diameter * Speed is regulated by a two-quadrant PWM servo amplifier which features outstanding linearity and excellent efficiency (90%) * With rotor inertia of only 0.0095g/cm2, the Minimotor achieves a continuous torque of 0.33mNm