23 Jul 2024


Hollow-shaft servo gearheads are `a first`

Hollow-shaft servo gearheads are `a first`

Alpha Gearheads claims to have developed the first hollow-shaft, right-angle gearhead for servo motors. The company says it has spent “several million” euros to adapt the hypoid gear technology previously used mainly in the automotive sector for industrial servo applications.

The resulting single-stage HG+ gearhead (above) is characterised by high input speeds (up to 6,000 rpm), low backlash (less than 4 arc-minutes), high torque (up to 400Nm), low noise (two thirds lower than conventional right-angle boxes), high efficiency, freedom from wear, and reversibility at all ratios.

Until now, right-angle gear heads used with servos have usually been coaxial gearboxes combined with right-angle gears, which were difficult to choose and install. Problems associated with bevel boxes include their low gear ratios (a maximum of 3 or 4:1), high noise levels, and the frequent additional cost of one or two extra planetary stages.

Although worm gearboxes can provide low noise levels and high ratios in a single stage, they are bulky, can suffer from wear, backlash and poor starting efficiencies, and are irreversible at high ratios.

The HG+ gearheads provide acceleration torques of up to 640Nm in five frame sizes, and single-stage ratios of 3:1 to 10:1. Their nominal input speed is up to 4,000, depending on the output torque. Alpha says that they can be mounted on any type of servomotor within five minutes.