Jockey wheel
From Wikipedia, the free encyclopedia
A jockey wheel is a wheel-based mechanical system used for steering or guidance, either:
- a guide wheel — usually operating as a pair — which is used to move, retain, locate and (usually) add tension to a chain, rope or cable which is then fed into the groove of another wheel, toothed wheel, cog or sprocket;
- a (frequently) retractable, smaller, height-adjustable wheel located on the front of a trailer or caravan for the low-speed manoeuvring or manual steering of said trailer-based unit when decoupled from the powered vehicle to which it was attached.