Robotic Mechanisms – CAGE Gears 51040

A cage gear, also called a lantern gear or lantern pinion has cylindrical rods for teeth, parallel to the axle and arranged in a circle around it, much as the bars on a round bird cage or lantern. The assembly is held together by disks at either end into which the tooth rods and axle are set. Lantern gears are more efficient than solid pinions, and dirt can fall through the rods rather than becoming trapped and increasing wear.

Sometimes used in clocks, the lantern pinion should always be driven by a gearwheel, not used as the driver. The lantern pinion was not initially favoured by conservative clock makers. It became popular in turret clocks where dirty working conditions were most commonplace. Domestic American clock movements often used them.