Vertically adjustable hitch

摘要

A vertically adjustable hitch for an agricultural tractor includes a pair of guide rails and a retainer which moves up and down on the rails. A chain has fixed ends and a central region which engages a pair of pulleys which are rotatably mounted on the retainer. As the pulleys rotate, they roll along the chain and move the retainer. A drive mechanism is coupled to rotate at least one of the pulleys. A locking mechanism is releasably engageable with the chain to prevent movement of the retainer relative to the chain.