Stepper Motors

Hybrid stepper motors are commonly perceived as voodoo by a lot of engineering designers. They are traditionally hard to select based on performance and a knowledge of how they work is essential to get the best performance out of a motor.

Stepper motors are ideally suited to low speed high torque applications where using a gearbox is not a viable option. They can be used with a relatively simple drive as indexing positional motors- you give it a pulse, it moves a set number of degrees and stops. Multiple pulses, know as pulse trains are fed into the motor drive and it indexes round accordingly. If the motor meets a heavier load than it is designed for it will simply not move. Under most scenarios this will not damage the motor although it may ‘squeal’ a bit. Under no power, a stepper motor can have a good amount of holding torque so can be used to hold a load still removing the need for an external brake. This is also referred to as detent torque.

If you want continuous motor revolution a stepper may not be correct and you could look to a brushless motor, but if you require simple indexing with minimal feedback, a stepper could be the way forward.

The manufacturers of the Nema framed hybrid stepper motors we work with are based around volume production. Following a strict project plan and sampling, they expect volume orders of 100 pieces plus. Please have this in mind when looking to us for stepper motors.

Common applications.

• Print head drive – fast accurate positioning back and forth.
• Indexing machines – move a set distance every time a signal is given.
• X-Y cutters and plotters – fast accurate positioning
• Rotating stages – motor indexes a known amount when given a pulse.