Dual speed focuser

Dual speed focuser design borrows the planetary gearing idea used in automobile gearboxes.

All the transmission inside a dual speed focuser is achieved via static friction.

The cylinder case of a dual speed focuser is fixed on the telescope tube.

An input axle penetrates through the hole on the center of the holder shelf and is pushed and tightened by three surrounding balls.

The metal balls then push the holder shelf and drive the output axle.

A dual speed focuser, replacing the original rack and pinion focuser of the Orion hit XT 10 dobsonian telescope .