Ball transfer unit

A ball transfer unit is an omnidirectional load-bearing sphere mounted inside a restraining fixture.

This permits manual transfer to and from machines and between different sections of another conveyor system.

[1] They are used in airports for luggage delivery, or in industry as part of manufacturing systems.

Prior to the invention of the ball transfer unit, first patented by Autoset Production Ltd in 1958,[2] these applications were solved by the use of inverted casters.

However, casters recognise a trail, meaning that the wheels had to align before directional change could be achieved.

Ball transfer unit
Cross-section through a spring-loaded ball transfer unit with a polymer seal ring and a drain hole in the bottom.