SELF-STEERING DOLLY FOR LONG LOAD HEAVY HAUL
A dolly for the transport of elongated loads which includes an adjustable steer linkage assembly, an adjustable steer ratio, means for switching between rear- and forward-steering, and manual over-ride of the self-steering configuration. All of these adjustments can be achieved without the need to manually delink subassemblies.
1 . A dolly for transport of an elongated load, said dolly comprising:
a chassis;
one or more steering axles
a load-bearing turntable mounted on said chassis;
a steering linkage for communication of rotation of said turntable to said one or more steering axles,
said steering linkage comprising:
a steering ratio adjustment means;
a steering linkage length adjustment means;
a means to adjust between front-wheel and rear-wheel steering; and
a means to adjust between self-steering and manual steering of said dolly;
wherein said steering linkage further comprises: an anchor point in communication with said turntable, said anchor point anchoring a length-adjustable first member in communication with said one or more steering axles on one side of a longitudinal axis of said dolly; and said anchor point adjustable in position relative to a central axis of said turntable.
2 . The dolly of claim 1 , wherein said length-adjustable first member is a hydraulic cylinder.
3 . The dolly of claim 1 , wherein said length-adjustable first member is pilot-operated for over-ride of self-steering.
4 . The dolly of claim 1 , wherein said steering ratio is determined by a distance between said anchor point and said central axis.
5 . The dolly of claim 1 , wherein said anchor point is a connection point between said length-adjustable first member and a second member mounted pivotally to said turntable, and said second member is locked in position by a linear actuator.
6 . The dolly of claim 5 , wherein said second member is a swing arm and said linear actuator is a screw type.
7 . The dolly of claim 1 , wherein a motor is used to adjust said anchor point.
8 . The dolly of claim 1 , wherein forward-wheel steering is obtained by placing said anchor point on an opposite side of said longitudinal axis; and rear-wheel steering is obtained by placing said anchor point on said one side of said longitudinal axis.
9 . The dolly of claim 1 , wherein said load-bearing turntable is mounted on an assembly comprising bearings to withstand a radial and an axial load.
10 . The dolly of claim 9 , wherein a tapered roller bearing assembly is used to withstand said radial load.
11 . The dolly of claim 9 , wherein a peripheral roller thrust bearing assembly is used to withstand said axial load.
12 . The dolly of claim 11 , wherein said roller thrust bearing assembly comprises a radially-oriented array of roller bearings.
13 . A device for withstanding a radial and an axial load on a load-bearing turntable, said device comprising: a tapered roller bearing assembly for withstanding said radial load; and a peripheral roller thrust bearing assembly for withstanding said axial load.
14 . The device of claim 13 , wherein said roller thrust bearing assembly comprises a radially-oriented array of roller bearings.