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).
Comparing the considerations for Girling and Lockheed hydraulically operated brake systems.
| Identifier | ExFiles\Box 121\1\ scan0333 | |
| Date | 22th October 1940 | |
| 1029 To Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby} Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby}1/ET.22.10.40. GIRLING BRAKE PATENT With regard to the Girling hydraulically operated brake layout with special handbrake, the main considerations are threefold:- 1. The expanders are operated through rollers instead of the sliding pieces used on the Lockheed system. The Girling method is to be preferred. 2. When the linings are badly out of adjustment, it is possible still to get good brakes by means of the handbrake in conjunction with the footbrake. There is little excuse for getting into this position, and in any case the lazy motorist will probably allow his brakes to get so bad that even the combination of hydraulic and mechanical brakes will be insufficient to stop him. Also, if under these conditions, one system fails, he will be left with no brakes at all. 3. The Girling system will be more expensive than the Lockheed, although probably no heavier. The Girling layout, including backplates, shoes and linings, but exclusive of rods and levers would be not less than £6.0.0, as compared with Lockheed's quotation of £4.10.0. Although we have had no success with our Girling 2-leading shoe layout, the hydraulic operation would probably give satisfactory braking with a slightly higher frictional coefficient of the lining. But we do not think it necessary to change from our present project of all Lockheed brakes for the Myth and Ripletto. Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby} | ||