Split-Pinion Ensures Precise Positioning on Material Feed Axis

Customer's Problem

A punch press manufacturer needed to precisely position a sheet of metal in order to accurately punch parts. The material feed axis had to be capable of high speed and acceleration, with high repeatability and no lost motion.

ATLANTA's Solution

To drive the axis, a Preloaded Rack & Pinion Drive System was selected. The system was comprised of a helical hardened & ground (HPR) rack & split-pinion shaft and a servo-worm reducer.

To eliminate the axis backlash, the axial spring pack on the split-pinion was preloaded to ensure no backlash developed during the machine operating cycle. The preload setting was based on the peak cycle loading and was fully adjustable on the machine.

The split-pinion shaft was supported by the hollow-bore of the servo-worm reducer, providing a rigid support and minimizing any radial deflection. A compression coupling, instead of a keyway, was used to lock the split-pinion shaft into place and prevent fretting corrosion.

The ultra-precise positioning of the preloaded axis drive improved the accuracy of the machine and the parts that it produced.