Free-Wheel Clutches - Sprag Clutch

Examples

Important applications of sprag clutches conveyers (backstopping) conveyers (speed compensation) copiers (paper feeding) furniture production (glue roller drive) high voltage switches mixers (safety clutch) motor bikes (automatic gear) packaging machines (overrunning clutch) paper handling (material feed) printing presses (ink roller drive) sowing machines (seed feeder) textile machines (material feed) winches (backstop)

Three basic applications of a Sprag Clutch

	Indexing elements: Indexing elements change an oscillating to an intermittent rotary motion. An example could be a ratchet or a stock-feeding device.
	Backstops: Backstops prevent self-reversing due to load condition when the machine is not activated.
	Overrunning clutch: Free-wheel clutches are also used as overrunning clutches to maintain driven unit activated even during slowdown, or in the case of two speed operation (by independent motors) to switch to the higher speed by passing the slower. The most notorious application is the bicycle.