Rotomation indexers use the same principle as a standard rotary actuator, where pistons drive a rack back and forth producing a rotary motion of the pinion. But instead of being part of the shaft, the pinion is separated from the output shaft by a one-way clutch. This clutch has a dual purpose, support the pinion on the shaft, and grip the shaft in one direction only, allowing free rotation in the opposite direction.
When the pinion is turning in the drive direction, the clutch grabs the shaft and turns it. When the pinion turns in the opposite direction, during the reset stroke, the shaft stays still because the clutch releases its grip and free wheels. A second clutch pressed into the body prevents the shaft from turning backward.
A ratchet attached to the shaft provides accurate stops. The ratchet has one tooth for each stop that the indexer will make in one revolution; for example, a ninety degree indexer has a ratchet with four teeth.

PA22 Pick and Place Rotary Actuator

Rotomation A032 Rotary Actuator with Vacuum Through Shaft. This miniature actuator can rotate products held by a vacuum cup attached to its shaft. The input vacuum port on the rear remains stationary to eliminate twisting hoses.

• Large hole through shaft for full flow
• Variety of shaft details available (1/8 NPT shown)
• No twisting hose

The rugged A032 fits in the palm of your hand and can be configured in millions of different ways, including your choice of two or three position motion, flexible porting arrangements, magnetic sensors, adjustable rotation, etc. The vacuum through the rod feature is also available on certain other Rotomation rotary actuators, including the unique indexing rotary actuators.

The Rotomation Indexing Actuator rotates in fixed increments in one direction with no accumulating error. Steps from 12 to 360 degrees are available. Great for indexing conveyors, star wheels, index tables, parts positioning, etc. Simple to operate using only a four way valve. High speed, rugged construction.