It consists of 2 plate cams fixed to the input shaft and a spider that supports the cam follower to the output shaft. This indexing drive has a plane cam mechanism designed so that the follower contacting the 2 plate cams on the input side serves to transmit rotation to the spider of the output shaft. Best suited for driving conveyors moving at large feed pitches or for intermittent indexing that stops at comparatively long intervals. The another is 3 plate cams designed as heavy load type. It more suits for conveyor rapid moving, stop at more long intervals and larger feed pitches.