DRIVES/MOTORS/CONTROLS

Heat taken out of variable speed work

* Electric motor company Leroy Somer has developed an AC machine for variable speed work that can, it says, produce constant torque over a 1:10 speed range without the need for thermal protection. Yet it costs up to 14% less than an equivalent standard motor.

The LSMV motor targets the demand for 0.75-132kW power outputs, which accounts for about half of the new and replacement market. It is presented as a good option for customers needing fixed speed now but the possibility of variable speed later.

Externally, the machine appears similar to a standard motor, with fully interchangeable frame sizes as well as Leroy Somer’s hallmark, a cast-iron mounting flange to cut noise. Internally, however, the machine is different. For example, by putting more material into the magnetic circuit the designers have reduced current density and its heating effect. A small motor and correspondingly lower-cost inverter can achieve the same performance as a larger de-rated motor. Constant torque can thus be guaranteed over the speed range, says the maker.

Other features include a shaft with guaranteed concentricity, ideal for high accuracy machine tool axis work. For speeds below 5Hz and above 4,000rpm, forced ventilation is an option. So is braking for speed-down or safety reasons, suitable for conveyors and cranes.

LEROY SOMER EXPRESS ENQUIRY CARD 200

* A mini positioning controller claims an impressive array of features despite its small size. Suitable for position and speed control of variable and two-speed drives and motors, the controller has inputs for incremental and absolute encoders. The GEL 8010 is said to be particularly suited to simple positioning tasks that require low-cost precision control.

MOTOR TECHNOLOGY EXPRESS ENQUIRY CARD 201

* A motorised slide package put together by three leading suppliers should help machine builders to cut development times, improve positioning and retain the benefits of a custom solution. XD linear slides from FlexLink have been adapted so a SmartDrive stepper motor can be bolted directly on to them. Systems integrator Rapier Control assembles the finished units. Also available is a multi-axis system that is built, wired and tested, together with software.

FLEXLINK SYSTEMS EXPRESS ENQUIRY CARD 202

* The West End production of Martin Guerre owes some of its success to a Quin 35-axis mini programmable transmission system (PTS). It creates a versatile set using open-sided 1.5 tonne trucks. These can move and rotate in any direction under their own power. Positioning information held on the control computer is transmitted to four mini PTS, one on each truck, by radio using a Modbus communications network. The truck’s location is pinpointed by a Wybron Autopilot that `talks’ to infrared/ultrasonic sensors above the stage.

QUIN SYSTEMS EXPRESS ENQUIRY CARD 203