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Motorized drive pulleys for belt conveyors offer an alternative to traditional chain and belt drive systems.
Of all the components in a conveyor system, the drive mechanism is the most expensive. It can account for III as much as two-thirds the cost of the entire system, as well as 80% of the maintenance and repair costs. It's no surprise, then, that many engineers put the drive mechanism at the top of the list when spec'ing out a conveyor system.
External chain and V-belt drive mechanisms are the traditional choice, but motorized pulleys - an old idea reborn with new technology - are beginning to live up to earlier promises. With integrated electronic intelligence, today's self-propelled pulleys are reliable, efficient, and virtually maintenance-free in many applications.
What is a motorized pulley?
A motorized pulley is simply a drum motor in which the outer shell rotates around a stationary shaft. The revolving member serves as a traction pulley, gripping and driving the conveyor belt. Electrical power leads pass through the stationary shaft to terminals within the pulley housing. Since the shaft end does not rotate, there is no need for slip rings to deliver electrical energy to the motor windings.
The entire internal mechanism - including motor, gears, and bearings - is completely sealed and protected by the outer metal drum. Oil inside the drum continuously lubricates the bearings and gears, and acts as a heat-transfer fluid by dissipating heat away from the motor windings. This keeps the motor cool, extends service life, and reduces maintenance. It also means designers can put pulleys in hot environments...