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).
Demonstration and the technical workings of Warner electric brakes.
| Identifier | ExFiles\Box 120\3\ scan0089 | |
| Date | 28th September 1934 | |
| x456 To E.{Mr Elliott - Chief Engineer} from Da.{Bernard Day - Chassis Design} c. Hs.{Lord Ernest Hives - Chair} Warner Electric Brakes. Messrs. Stoddart and Warner came here on Wednesday to demonstrate the Warner electric brake. Mr Stoddart is the representative of Barber and Colman the agents, and Mr Warner is the son of the Inventor. Each brake is a self contained unit, consisting of the brake parts and the servo which applies them. No interconnection for compensation is possible. They depend on precise similarity of manufacture and adjustment to get equal braking. The brakes are flexible internally expanded band brakes, the band being stopped at one end and pushed at the other. They are fully self wrapping and very dependent for their effectiveness on co-efficient of friction. The push is supplied by the electrically operated servo. This consists of an armature plate, driven by the brake drum, which is attracted to a friction lined magnet surface on the brake carrier. The rotation of this magnet acts on one or other of the ends of the brake band, either directly or through short levers. The surface of the friction lined magnets is such that there must be magnetic contact without measurable air gap between the inner and outer rims of the magnet, which are its poles, and the armature plate, at the same time as the armature plate is pressing against the friction surface. They declare that this condition is maintained throughout the life of the magnet and that the metallic and friction parts of the surface wear away equally. There is a constant load (of about 4 lbs) between the armature and the magnet against which the | ||