HYDROSTATISK HJELPKRAFTSTYRINRETTNING

摘要

Dual double acting servomotors hydraulically pressurized are provided wherein the pistons have shunt valve means actuatable at limit of movement of the pistons to shunt high pressure fluid at one side of the piston to the low pressure side of the piston then being exhausted. This results in relieving the stress otherwise effected against steering mechanism limit stops by continued application of high pressure feed to the pressurized chamber. The system encompasses steering control and shunt circuit valve means automatically actuated by differential pressures so as to direct pressure and exhaust flow selectively to and from the chambers of the respective cylinders from an engine driven pump and a manual metering pump for operating the steered wheels of heavy duty vehicles and which valve means effects bypassing of the engine driven pump pressure feed directly to one servomotor while feeding the combined pressures of that pump and the metering pump to the other. Both servomotors act to effect steering with no loss of synchronization.