STUDY OF AN EMERGENCY DEVICE FOR RUBBER TRACKED TRACTORS EQUIPPED WITH DIFFERENTIAL STEERING

摘要

For rubber tracked tractors that have a forward speed above 4,2 m s~(-1) the steerage control cannot have effected with frictions and steering brakes system, as in the metal tracked tractor, even if the commands are hydraulic. In this paper two different technical solutions inherent the auxiliary emergency steering devices for the rubber tracked tractor equipped with differential steering were studied. In the first solution the device has provided of auxiliary hydraulic pump driving by electric motor fed by the electric accumulator of the tractor. The hydraulic circuit in pressure from the delivery of the auxiliary pump acts on the steering hydraulic motor of the " Dual differential ". In the second solution the device, through the pump of the hydraulic system, uses the tractor kinetic energy in the action of the intervention of emergency steering, doing that the steering happens through the brakes of service, places on the two extremities of the differential steering gear.