Steering control system for trailers

A steering system for trailers having an axle carrying a steering knuckle at each end and a tie rod extending between said steering knuckle's for pivoting steerable wheels rotatably and pivotally mounted thereon, said system being operable to pivot said steerable wheels to control a turning direction of said trailer responsive to a turning direction of a towing vehicle, said system comprising:

• a. a position arm attached to said towing vehicle to indicate the orientation thereof;
• b. a hydraulic master cylinder including a piston having a free end for connection to said position arm;
• c. a hydraulic slave cylinder including a piston arm for attachment to one of said steering knuckle's on said axle of said trailer;
• d. a pair of hydraulic lines for fluid communication between said master cylinder and said slave cylinder;
• e. a valve in fluid communication with both of said hydraulic lines for controlling fluid pressure flow between said master cylinder and said slave cylinder, said valve having a first position for directing fluid pressure flow as said trailer is towed in the forward direction and a second position as said trailer is moved in reverse;
• f. a locking mechanism comprising a rotatable locking ring disposed about said axle carrying said steering knuckle to which said slave cylinder piston arm is attached, said locking ring having a pair of extending arms, said arms being oriented with respect to one another between a vertical plane and a horizontal plane responsive to the rotation of said ring, a stop plate carried on said axle adjacent the terminus of said extending arms to act against said arms and serve as a stop to prevent pivoting of wheel hubs when said extending arms are aligned in a horizontal plane, said wheels being free to pivot when said extending arms are aligned in a vertical plane, a friction clutch assembly comprising a wedge plate concentrically affixed in said locking ring for rotation therewith, a surface of said wedge plate facing said wheel being provided with at least one locking ramp, a wedge shaped radial pad disposed on said locking ramp, said wheel hubs rotating independently of said locking ring when said wheel hubs are rotating in a reverse direction and said extending arms are aligned in a vertical plane, said wedge shaped radial pad being forced along said locking ramp into fictional contact with said wheel hub to rotate said locking ring responsive to the rotation of said wheel hubs thereby to move said extending arms into alignment in a horizontal plane when said wheel hubs rotate in the forward direction.