Optical Rotary Encoders Suited to Dynamic Stages

Heidenhain's ERO 1200 and 1400 series of modular optical rotary encoders are designed for motion control use on dynamic stages and machines in the general automation or semiconductor industries, such as pick-and-place machines. Because they have no integral bearings, the encoders enable ±0.02 mm of axial motion, providing room for thermal growth of motors or machines, the company says. The ERO 1200 and 1400 series support line-driven TTL outputs (RS-422) as well as differential 1-V peak-to-peak signals, which can be interpolated for use in a speed control loop.

The ERO 1200 encoders are available with a 10- or 12-mm shaft, offering a graduation accuracy of ±6 arcseconds. The smaller, versatile ERO 1400 encoders are available with through-shaft diameters of 4, 6 or 8 mm, as well as a self-centering slide mechanism. The ERO 1400 series also features onboard interpolation to achieve resolutions of 37,500 signal periods per revolution, facilitating use on high-resolution viscometers or portable mass spectrometers.