3767292 is referenced by 18 patents and cites 2 patents.

A device is provided for assisting an operator in backing up a trailer-towing or tractor vehicle to couple a ball hitch member mounted on the rear of the vehicle with the complementary socket hitch member mounted on the tongue of the trailer. The device comprises a bracket adapted to be mounted on the trailer, and particularly on the vertical bolt utilized for clamping the bottles of cooking and heating gas, and provided at one end with means such as a clamp adapted to engage and support a large size hubcap having a convex reflecting surface. The hubcap serves as a convex mirror and provides an excellent image of both hitch members for enabling the operator to steer the tractor vehicle in the proper direction, and provides a precise indication when the socket member is superposed over the ball member.

Title
Aligning device for tractor hitches
Application Number
05/297,984
Publication Number
3767292
Application Date
October 16, 1972
Publication Date
October 23, 1973
Inventor
Rutkowski Phillip R
IPC
G02b 05/10
B60D 01/36
B60D 01/00
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