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).
Continuation of a technical description for a self-energising brake system.
| Identifier | ExFiles\Box 85\1\ scan0372 | |
| Date | 29th November 1937 guessed | |
| SELF-ENERGISING BRAKE. (Continued). The load at which the servo action commences is controlled by a combination of spring resistance and the pedal pressure applied. The power of the action increases in direct proportion to the speed/load of the vehicle. Should the braking power lock the wheel, the tendency of the rocking-plate to revolve thus ceases, and it is returned to the "Off" position by its return springs. The shoes are then held expanded by the foot pressure only, the primary cam being still "On". This being very considerably less than the servo pressure, it allows the wheels to be partially released, the servo cam again coming into operation when the wheel recommences to revolve. This servo action operates with equal efficiency both in forward and backward movement of the vehicle, the "Off" position being the centre of the arc of travel of the rocking-plate which is free to rotate in either direction. In one direction the cams coincide and in the other they form an "X". The servo cam is self-adjusting for wear of the brake linings. Whilst the control of the brakes is taken by a common agent, e.g., the foot-pedal or hand-lever, the servo power is determined by the speed/loads of the individual wheels which, of course, vary considerably as when cornering, ascending or descending hills etc. The whole assembly is simple, robust and comparatively inexpensive to manufacture. ---------------- Patent applied for by: Harold B. Mead, 71, Albert Road, I L F O R D, Essex. | ||