Convertible rail-highway shunting locomotive

Claim 1

A shunting vehicle having a chassis supported on railengaging rubber-tired wheels, retractable arms on the chassis, flanged rail-engaging wheels carried by the retractable arms and engaging the rails thereby retaining said rubber-tired wheels on the rails, said chassis having a front end and a rear end, and a coupling subchassis on the chassis at its rear end, and comprising the improvement of a flat horizontal member on the chassis movably supporting a complementary flat horizontal member on the subchassis, a pair of slots in one of the members, a corresponding pair of pins in the other member passing through the slots, and bearing plates pivotally supported by the pins and slidably engaging the edges defining the slots, the slots being positioned symmetrically with respect to the longitudinal centerline which extends between the front and rear ends of said member which contains them and diverging away from each other in the direction of the front of the chassis so that when rotation of the subchassis with respect to the chassis takes place under operating conditions, said bearing plates slide within said slots and the effective center of rotation of the subchassis is transferred forwardly of the slots.