From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Investigation into methods of preventing mud and water ingress into brake drums, with diagrams of different cover designs.
| Identifier | ExFiles\Box 5\3\ 03-page215 | |
| Date | 1st February 1925 guessed | |
| contd :- -3- [DIAGRAM - FIG II] A - COVER CHAMFERED AT 45° B - COVER & DRUM CHAMFERED AT 45° C - STEPPED COVER & WIDE DRUM If the car is driven through a puddle, water is washed on to the drum and washes the mud inside the drum. The type of cover shewn in Fig. III. was then tried, but gave no improvement. [DIAGRAM - FIG III] In order to find out whether mud creeps along or is blown along the outside diameter of the brake drum and so between the drum and dust cover or into the brakes, some brackets were made carrying felt strips so arranged that the brake drum was continually being wiped, the mud wiped off being wiped away from the dust cover. This kept the drums perfectly clean so that there could be no question of mud creeping along the drum and into the brakes. Examination of brakes after running along dirty roads, showed no improvement at all due to keeping the drums clean. From this we can state that any mud entering the brakes is due to a direct stream of mud and water on to the contd:- | ||