Adjustable Mounting for Pivotal Wheel Support

The herein invention is an improvement on means to adjust the support of a pivot shaft such as shown in U.S. Pat. No 3,880,444 granted to Alvin C. Bridges on Apr. 29, 1975 and the references therein cited. Adjustability of the pivotal wheel mounting was heretofore approached from the point of view of improving the mounting of the pivot shaft within the channel frame of the vehicle and then to have various devices for preventing the pivot shaft from turning when subjected to torsional forces and shocks.

The primary object of the invention is to have a positive adjustability and support of the pivot shaft outside of the hollow channel frame of the vehicle so that the location of the pivot shaft can be adjusted in either direction in an easily accessible location and wherein the pivot shaft is positively held in position on the channel frame, and where the unit can be quickly and easily mounted and replaced and adjustment can be quickly accomplished and the pivot shaft can be positively held against shifting.

FIG. 1 is a perspective developed view of the adjustable mounting.

FIG. 2 is a fragmental sectional view, the section being taken on lines 2--2 of FIG. 4.

FIG. 3 is an end view showing the locking end.

FIG. 4 is a longitudinal section of the mounting.

FIG. 5 is a side view of the mounting in relation to the vehicle wheel.

A pivot shaft 1 is fixedly mounted in the legs 2 of a pivot frame of U-shaped cross section, the base 3 of which has an adjusting or travelling stub shaft 4. The pivot frame is slidable in a box 6 of substantially rectangular cross section. The box 6 has perpendicular sides 7 and top and bottom walls 8. The box 6 is tubular, namely both ends are open. The usual pivoted arm 9 is pivoted on the pivot shaft 1 and extends through one open end of the box 6 for supporting the wheel of a vehicle in the usual manner.

Near the other end of the box is provided a fixed back-plate 11. A nut 12 is rotatably held in the fixed back plate 11 and it engages the travelling stub shaft 4 so that when the nut 12 is turned the stub shaft 4 travels in the respective direction thereby pulling or pushing the U-shaped pivot frame with the pivot shaft 1 therein in the box 6 in the selected direction for adjusting the location of the pivot shaft 1 according to the wheel alignment required.

The nut 12 is locked in the adjusted position by releasable means, for instance by a locking plate 13 which has therein a polygonal socket 14 fitting over the nut 12. A hole 16 in the locking plate 13 accomodates a pin or a set screw 17 fitting into the corresponding hole in the fixed back-plate 11 thereby to prevent accidental turning of the nut 12.

The above described assembly is mounted on the usual channel frame 18 of the vehicle. In a tubular member 19 extending across the channel frame 18, in which the usual pivot is presently located, is placed a bolt 21. For assembly purposes the perpendicular sides 7 of the box 6 have opposite holes 22 one of which is large enough to accomodate the head of the bolt. The hole 22 adjacent to the channel 18 is countersunk to fit the bolt head 23 and prevent it from interfering with the sliding of the pivot frame in the box 6. Inasmuch as the usual hole 24 on the channel frame adjacent to the position of the box 6 is normally larger than the bolt 21, a tapered bushing 26 is provided along the bolt 21 so as to extend into the end of the tube 19 so that the larger end of the bushing 26 is pressed into the larger hold 24 thereby to hold the bolt 21 in position. The threaded end 27 of the bolt 21 extends through the hole in the farther wall of the channel frame 18 and is held in place by the usual nut 28.

To prevent the turning of the box 6 about the bolt head 21 there is another bolt 29 provided near the end of the box 6 which is screwed into the adjacent wall of the channel frame 18. The head of this bolt 29 is countersunk so that it is flush with the inner surface of the adjacent side 7 and does not interfere with the sliding of the legs 2 of the pivot frame.