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).
Design and performance of a vehicle's braking system.
| Identifier | WestWitteringFiles\L\Jan1924-March1924\ Scan45 | |
| Date | 1st January 1924 | |
| TO RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} & DA.{Bernard Day - Chassis Design} FROM R.{Sir Henry Royce} SECRET. R2/M1. 1. 24. Copy to CJ. BJ. WOR.{Arthur Wormald - General Works Manager} HS.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} MP. E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C.111. RE. BRAKES. SYSTEM. I feel sure that we must persevere with the scheme we have in hand. I was very pleased to see how well it worked when we removed the rather unsuitable pull off springs on the front axle. There is no real reason why both brakes should not come on at the same time and always with the same proportions. (Any other scheme on this chassis seems hopeless, even not counting the time.) SERVO. This seems quite O.K. but a little too effective. The leverage upon it might be tried somewhat less, and with less than the original length of embrace so as to give it the best chance of consistent working. The springs should be tried of increased strength to open the shoes between the shoes and the pull tried in such a direction as to need following up by the foot. HOLD OFF SPRINGS. Owing to the good mechanics of our cams we can do with light pressure hold off springs, really hardly anything more than between the shoes, but we have decided to fit some giving practically constant rating, and creating very little shaft friction. These ought to do much good and are important items, as we proved. BRAKE SHOES. These have proved to be of the greatest importance; for simplicity and practicability it would seem that the semi-flexible fixed camshafts are to be preferred, but I think various proportions of jointed shoes both lapping and non-lapping should be also on trial to find which succeeds best, and also find the best combination of shoes for floating fulcrum. We also have had the idea of jointed lapping shoes with long backward shoes which again might be semi-flexible. This may work well and get over some of the troubles with the stops. JAGGERS. These are nearly a thing of the past though Mr.Hives could get them when rear brakes were disconnected and the compensator wedged. None of us could make any such effect so we must have touched the spot in the modification to the shoes. AXLE. Mr. Day and I schemed a rather better arrangement of shoe and drum support which promises to be good for the Goshawk. Perhaps this also might be good for EAC.111. This should be looked at to see if it is worth while trying this scheme on the 40/50. or EAC.1. and 11. It is now post time, so I must leave the remainder for tomorrow. R.{Sir Henry Royce} | ||