Draft control system for agricultural tractor

摘要

A draft control system of the type in which a mechanical spring is employed to balance the draft forces of an implement trailed behind the tractor so as to correct the working depth of the implement in accordance with changes in draft forces, in which the feature is the use of a hydraulic force-amplifying device to increase the responsiveness of the system so as to minimize the forces required to effectuate regulation of the working depth of the implement.