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).
Issues and proposed modifications for brake and differential systems.
| Identifier | ExFiles\Box 85\1\ scan0249 | |
| Date | 14th November 1936 guessed | |
| (sheet 2) (4) The front brakes are operated by a pull rod which is fitted with a double fork. We think this is satisfactory, but we want to have the end of the rod butted with the thread of larger diameter than the rod, to avoid breakage of the latter. (5) The rear differential requires universal connecting forks on the transverse rod, and a rotating fork joint on the longitudinal link such as we found we had to use on Phantom III to provide enough differential movement. The differential effect allowed by just plain forks is so very small that there is a danger of chassis being sent out without any at all in one direction. (6) The operating rope for the rear brakes might be connected direct to the differential without the use of the intermediate swinging lever. This is not an essential alteration but if it can be carried out weight and cost are saved. Rm{William Robotham - Chief Engineer}/AFM{Anthony F. Martindale} has agreed to try the brakes coupled up in this way. (7) The stop for taking care of a broken brake connection as arranged relies on the lateral rigidity of the gearbox crossmember. We feel however that this gearbox crossmember is too flimsy and flexible for this particular purpose. We have arranged with Rm{William Robotham - Chief Engineer}/AFM{Anthony F. Martindale} to disconnect the rear brake rope to make a test of this feature. (8) Some springs have been rigged up with a lever to load up the brake linkage behind the servo to prevent judders and brake thumps. This requires designing into the job to make it suitable for production. The servo is not fitted with the end spring washers in this case. (9) The rear brake adjustment is inaccessible but not entirely so. It can be reached by removing the rear seat cushions and board, but is a somewhat dirty job to carry out. Rm{William Robotham - Chief Engineer}/AFM{Anthony F. Martindale} is of the opinion that this does not matter very much as our experience is that all owners bring their cars back to the depot to have their brakes adjusted. | ||