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).
Letter from France discussing the development of slow speed servo brakes, conversion parts for the 40/50 model, and observations on competing designs.
| Identifier | ExFiles\Box 30\6\ Scan169 | |
| Date | 27th January 1924 | |
| To C.J. from R.{Sir Henry Royce} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} Hs.{Lord Ernest Hives - Chair} PN.{Mr Northey} BJ. BY.{R.W. Bailey - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} X1559 La{L. A. Archer} Villa Mimosa, Le CanadelHenry Royce's French residence, Var., France. Jan. 27th. 1924. X.1559. X.9770 X.9940. I am writing this to you to save postal time, and that you should know my views at the first possible moment. Yesterday I sent you a letter, the chief parts of which I sent by telegram very early this, Monday, morning. Here I give a few more notes omitted from my yesterday's letter. I only realised recently that the very slow speed servo was the simplest way of preventing the brakes being vigorously applied suddenly, and we and others did not know there was so much necessity in moderating the speed of application, this is my great point in striving for the universal use of the slow speed servo. Only such experience as we have had would teach. The other difficulties of heat and wear and inconsistent working which we have experienced I believe would be surmounted but it would still leave us the trouble of moderating the speed of application. Regarding parts for conversion of present 40/50, we still consider the parts of our brakes on the axles, and equalisers as good as or superior to the best and I think these parts should be produced and fitted to cars in production. But the operating part i.e., 'servo' and other details should not be put into production as serious changes will probably be made. I have asked Mr. Rowledge to let me have his views. I noticed a big Panhard here with front wheel brakes with novel mechanism but the rather delicate operating levers stand out and below the axle as if they would be caught by a big stone or bad road and be damaged or put on the brakes. It has sleeve valve engine and smoked badly as they all do. Perrot some little time ago brought a design of self servo brakes which I believe Lanchester and /or Sunbeam adopted, I did not favour them because I thought they would vary in being equal between the wheels. We would now realise that this error would be greatly increased by rust and friction in the operating shafts. They would also be capable of this too sudden application which we have found to be so disastrous. R.{Sir Henry Royce} | ||