Semiconductor robots lead the way - New generation gearing is improving robotic performance

Wafer handling robots used in the semiconductor industry have the challenging task of stacking silicon wafers into a cassette tower by accurately detecting wafer presence and position. This is achieved by calculating the wafer centre to an accuracy of 5000ths of an inch to reduce errors. Characterised by a very short overall length and a lightweight design, the CSD Series delivers the required high power to weight ratio, in a compact form factor and is available in two variants.

The CSD-2UH range boasts the smallest outside diameter, offers a torque capacity of 12Nm to 820Nm and is available in seven sizes in ratios of 50, 100 and 160:1. The second variant, CSD-2UF, has the shortest overall length and offers a torque capacity of 12Nm to 450Nm in six sizes and the same three ratios.

"We've designed the CSD range to be compatible with existing systems," explained Graham Mackrell, managing director of Harmonic Drive UK. "The entire range mounts easily with any standard servo actuator. So while it's primarily targeted at the robotic and semiconductor market, it will perform equally as well in other demanding high precision applications such as broadcast, aerospace and machine tools. The simple installation means that users can take advantage of the low weight and compact size to easily absorb high loads.

"The high level of positioning accuracy means the CSD achieves stable machine characteristics and short cycle times. For users that need even higher load carrying capacity, the CSD-2UF has an output bearing with a high tilting rigidity and a central hollow shaft with a diameter between 9mm and 37mm."

The inclusion of a hollow shaft allows cables, shafts, pipes, laser beams and other services to be passed through the centre of the unit. The space saving design is essential in the semiconductor market where space is at a premium and robots must perform in ever more demanding environments.