This device consists of a circular steel plate and a drive for turning it. Parts rest in nests spaced equally along the table’s circumference. Self-contained machines and tooling for specific tasks are arrayed around the perimeter. As the table rotates, it stops intermittently to “dwell” for a fixed period of time, so that an assembly operation can be performed at each station.

The operation is analagous to that of a rotary dial assembly machine, except that in the latter, the operations at every station are fully automated. However, with the proliferation of sophisticated motion control systems, the practical distinction between the two approaches is mainly cost. Rotary indexing tables are typically smaller and more economical. Rotary indexing tables work well with machines that perform simple, fast, vertical operations, such as presses, screwdrivers, riveters, dispensers, pad printers, pick-and-place units, and ultrasonic or resistance welders. Parts can be loaded and unloaded manually or automatically.