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).
Single ratchet servo scheme for braking.
| Identifier | Morton\M20.1\ img020 | |
| Date | 25th April 1924 | |
| ORIGINAL SECRET. TO H.R. & B.A. FROM R.{Sir Henry Royce} R1/M25.4.24. Copy to - C.L. S.H. R.J. H.S. H.Y. E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. Y9910 SERVO - SINGLE RATCHET SCHEME. (1) Pleased you have realised by road experience my point of braking at close distances and slow speeds. (2) Your views also shew that for good control of the car the servo must assist the foot as promptly as possible. Derby have told us that jaggers may occur if brakes suddenly applied, so I have done my best to avoid increasing the speed of the servo greater than Hispano - (speed, and angle of action considered.) Therefore do not alter the angle of action of the servo from the 90° and say 45° for the pedal lever. Do not run the servo faster than about one tenth of the transmission speed. The above scheme allows for the least possible distance lag of any scheme I know, and it is possible that the virtues it gives are those we must have, even if we have to sacrifice servo braking backwards. This was the reason for my telegram of the 22nd to Derby, and for the enclosed sketch which shows how it can be applied to the servos lately designed which is fortunately a very simple modification. This scheme is one which was put aside when Mr. Rowledge's double acting scheme was suggested. (1) | ||