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).
Remarks dictated by Mr. Royce on the 'Goshawk' pedal mechanism and brake gear.
| Identifier | WestWitteringFiles\E\November1920\ Scan4 | |
| Date | 19th November 1926 | |
| To DA{Bernard Day - Chassis Design} from E.{Mr Elliott - Chief Engineer} Copy to CJ. " " HS.{Lord Ernest Hives - Chair} " " EFC. X.3605 ORIGINAL RECEIVED 19 NOV 1926 RE "GOSHAWK" BRAKE GEAR. Kindly note Mr. Royce has dictated the following remarks with reference to the schemes of "Goshawk" pedal mechanism and brake gear :- "Pedal shaft has too much torsional deflection. The arrangement should be made as "Buzzard" which was done to avoid this, and allow of adjustment from outside the frame. We send a sketch of simplified R.R. foot brake adjustment which you should modify. Elasticity should be reduced to a minimum in a foot brake mechanism. The anlge of the levers seems quite wrong. The driving levers should commence at half stroke. All driven levers should be gaining in length and leverage, and all driving levers should be decreasing in effective lengths and leverage. The alteration from 45° to 30° in a position of the brake countershafts of the rear acle is really a disadvantage because of the bad angles of the levers and the bad geometry of the cables. The position at 45° is preferred. A certain amount of fouling between the brake cables and the cross member opposite the centre of the rear springs is admissible, and a certain amount of thickness for the rubber buffers over the rear axle should be allowed for on full bump, under which conditions the cables may still foul the cross member in question. Both brake differential countershafts should be brought in front of cross member which is to carry them. The differential spider should in each case be driven by the casing, as arranged on the brake gear which was made to suit the 3/19 box on the 40/50 H.P. chassis. The foot brake adjustment previously mentioned is inserted in the form of an intermediate countershaft between the foot pedal and the differential shaft. (Contd.) | ||