Abstract: A drum braking system having a spindle and backing plate affixed thereto. The system includes a drum rotating on the spindle. The drum has an inside surface with integral notches that are machined or cast into the drum. When the brakes are applied, brake shoes are actuated to contact the inside surface to create drag between the drum and the spindle. A sensor is fixed with respect to the spindle or backing plate that detects the notches when the drum rotates about the spindle. A portion of the inside surface with the integral notches is shared with the brake shoes so that applying the brakes prevents buildup that could contact the sensor. The sensor is positioned radially to reduce the effect of drum endplay on detecting of the notches.

Abstract: A cap is provided for covering the threaded end of a removable spindle, having a cover with thread engaging tabs extending from a reservoir basin. The tabs include surface projections for retaining the cap to the spindle threads. The tabs are formed to fit within available slots of a slotted hex nut connected to the spindle. The cap includes a separately formed skirt or guard to make flexible surface contact with the torsion arm or spindle supporting structure. The skirt can include a sacrificial anode region to provide cathodic protection for the spindle threads and spindle retention nut. The skirt is removable from the cap so that the cap can be reused with a new skirt. The cap is formed to be used with existing spindle assemblies and to be reusable.

Abstract: A drum braking system having a spindle and backing plate affixed thereto. The system includes a drum rotating on the spindle. The drum has an inside surface with integral notches that are machined or cast into the drum. When the brakes are applied, brake shoes are actuated to contact the inside surface to create drag between the drum and the spindle. A sensor is fixed with respect to the spindle or backing plate that detects the notches when the drum rotates about the spindle. A portion of the inside surface with the integral notches is shared with the brake shoes so that applying the brakes prevents buildup that could contact the sensor. The sensor is positioned radially to reduce the effect of drum endplay on detecting of the notches.