Planetary gears and special gears Our planetary gears excel through their compact size and high efficiency. Switching planetary gears provide the option of using several different transmission ratios or of interrupting the transmission of power. The switching can be mechanical, pneumatic, hydraulic or electrical. These are essentially supplied to four market segments: DESCH Centrifugal Drives DESCH Machine Tool Drives General Mechanical Engineering And System Construction DESCH BSI-Bevelled Planetary Gears