Worm-Drive Rotary Stages Launched By Aerotech

Aerotech has launched a range of precision worm-drive rotary stages featuring large through-apertures and a preload system that provides a high level of accuracy with minimal wear. The AGR series covers five models with internal diameter from 50-200mm and is available with continuous 360deg travel, or with a mechanically limited travel range (down to 5deg).

Axial load capacity is up to 570kg and rated speed to 30rpm; and the range includes optional directly mounted encoders for best performance repeatability and negligible levels of hysteresis and backlash. Typical specifications across the AGR series include a 120 arc-sec positional accuracy without encoder fitted and 20 arc-sec when the servomotor mounted encoder option is used. Corresponding without- and with- encoder specifications for bidirectional repeatability are 30 arc-sec and 8 arc-sec.

Stage resolution, with a 2500 line servomotor mounted encoder fitted on the largest stage, is 2.1 arc-sec - while the same size stage with a directly mounted 40000 lines per revolution encoder achieves 32.4 arc-sec. Aimed at general-purpose rotary positioning applications in research, industrial production and manufacturing test applications, the AGR series has been designed to accommodate the through-aperture mounting of additional equipment and services such as lenses, mirrors, slip rings or cable assemblies on high-precision positioning systems.

The main housing and table top are manufactured from a lightweight aluminium alloy, which ensures maximum structural stiffness and a reduced mass for multi-axis set-ups and other weight-critical applications. The AGR series also benefits from a larger dual pre-loaded angular contact bearing-set to provide the high load handling required for offset and awkward payloads, while maintaining the minimal error motion performance required for high-precision positioning.

Other AGR series options include a choice of Aerotech's high-performance brushless servomotors or stepper motors in various orientations with rear-shaft mounted encoders and brakes. A labyrinth sealing kit is also available for stage sealing in arduous machining environments, and vacuum-compatible versions are available for levels down to 10-6 torr.