Antijackknifing device

Claim 2

In a motor and trailer vehicle combination comprising a motor vehicle and a trail vehicle, means coupling said vehicles to each other for relative pivotal movements in the horizontal plane, an antijackknifing device comprising a variable length link connected at its opposite ends to said respective vehicles at points spaced from the pivotal axis of said coupling means whereby movement of said vehicles from aligned relation with each other changes the length of said link, means for selectively locking said link against changes in length, said link being arranged such that relative movements of said vehicles away from aligned relationship causes changes in the length of said link in one diRection and relative movements of said vehicles toward aligned relationship causes changes in the length of said link in the opposite direction, and means independent of said locking means to facilitate changes in the length of said link solely in said opposite direction and thereby facilitate return movements of said vehicles toward aligned relationship though said locking means remains locked.

Claim 3

In a vehicle combination according to claim 1, means for selectively actuating said locking means.

Claim 4

In a vehicle combination according to claim 2 having vehicle brakes, means for selectively applying said vehicle brakes, said actuating means including means responsive to said selective brake-applying means.

Claim 5

In a vehicle combination according to claim 3, said actuating means including means independent of said selective brake-applying means for selectively energizing said anti-jackknifing braking element.

Claim 6

In a vehicle combination according to claim 1, said link comprising a fluid filled cylinder and a piston longitudinally movable therein, normally open conduit means connecting opposite ends of said cylinder, said locking means comprising a normally open valve in said conduit means, and means for selectively closing said valve.

Claim 7

In a vehicle combination according to claim 5, said piston being movable in one direction responsive to relative movements of said vehicles about the axis of the coupling away from aligned relationship, and in the opposite direction responsive to their relative movements toward aligned relationship, said facilitating means comprising check valve means in said piston constructed to facilitate movements of said piston solely in said opposite direction when said normally open valve is closed and thereby facilitate return of said vehicles to their normal aligned relationship.

Claim 8

In a vehicle combination according to claim 6, said means for selectively closing said valve comprising a solenoid, a source of electric power, a conductor connecting said source and said solenoid and including normally open switch means.

Claim 9

In a motor and trailer vehicle combination comprising a motor vehicle and a trail vehicle, means coupling said vehicles to each other for relative pivotal movements in the horizontal plane, an antijackknifing device comprising a variable length link connected at its opposite ends to said respective vehicles at points spaced from the pivotal axis of said coupling means whereby movement of said vehicles from aligned relation with each other changes the length of said link, means for selectively locking said link against changes in length, said link comprising a fluid filled cylinder and a piston longitudinally movable therein, normally open conduit means connecting opposite ends of said cylinder, said locking means comprising a normally open valve in said conduit means, means for selectively closing said valve, said means for selectively closing said valve comprising a solenoid, a source of electric power, a conductor connecting said source and said solenoid and including normally open switch means, vehicle brakes, and means for selectively applying said brakes, said switch means being closable responsive to applications of said brakes.

Claim 10

In a motor and trailer vehicle combination comprising a motor vehicle and a trail vehicle, means coupling said vehicles to each other for relative pivotal movements in the horizontal plane, an antijackknifing device comprising a variable length link connected at its opposite ends to said respective vehicles at points spaced from the pivotal axis of said coupling means whereby movement of said vehicles from aligned relation with each other changes the length of said link, means for selectively locking said link against changes in length, said link comprising a fluid filled cylinder and a piston longitudinally movable therein, normally open conduit means connecting opposite ends of said cylinder, said locking means comprising a normally open valve in said conduit means, means for selectively closing said valve, said means for selectively closing said valve comprising a solenoid, a source of electric power, a conductor connecting said source and said solenoid and including normally open switch means, vehicle brakes, and means for selectively applying said brakes, said switch means being closable responsive to applications of said brakes.

Claim 11

In a vehicle combination according to claim 1, said motor vehicle comprising a tractor and said trail vehicle comprising a semitrailer pivotally supported on the rear portion of said tractor for pivotal movement with respect thereto about a vertical axis.

Claim 12

In a motor and trailer vehicle combination comprising a motor vehicle and a trail vehicle, means coupling said vehicles to each other for relative pivotal movements in a horizontal plane, an antijackknifing device comprising a variable length link connected at its opposite ends to said respective vehicles at points spaced from the pivotal axis of said coupling means whereby movement of said vehicles from aligned relation with each other changes the length of said link, means for selectively locking said lInk against changes in length, said motor vehicle comprising a tractor and said trail vehicle comprising a semitrailer pivotally supported on the rear portion of said tractor for pivotal movement with respect thereto about a vertical axis, said coupling means comprising a fifth wheel rotatably mounted on said tractor and held against rotation with respect to said trailer, said fifth wheel having means forming the pivotal connection of said link to said trailer.

Claim 13

In a motor and trailer vehicle combination comprising a motor vehicle and a trail vehicle, means coupling said vehicles to each other for relative pivotal movements in a horizontal plane, an antijackknifing device comprising a variable length link connected at its opposite ends to said respective vehicles at points spaced from the pivotal axis of said coupling means whereby movement of said vehicles from aligned relation with each other changes the length of said link, means for selectively locking said lInk against changes in length, said motor vehicle comprising a tractor and said trail vehicle comprising a semitrailer pivotally supported on the rear portion of said tractor for pivotal movement with respect thereto about a vertical axis, said coupling means comprising a fifth wheel rotatably mounted on said tractor and held against rotation with respect to said trailer, said fifth wheel having means forming the pivotal connection of said link to said trailer.

Claim 14

In a vehicle combination according to claim 1, said trail vehicle being a separate trailer having a rigid forwardly extending tongue, said coupling comprising mating pivot members on the forward end of said tongue and the rear end of said motor vehicle, said variable length link being connected to said motor vehicle rearwardly of said coupling and having its axis normally aligned longitudinally of the vehicle with said pivot members.