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).
Calculations for alterations to Peregrine brakes to align them with the 20/25 HP model.
| Identifier | ExFiles\Box 1\10\ B001_X106 TO X 110-page012 | |
| Date | 7th November 1932 | |
| γ 106. For Files. 7.11.32. ALTERATIONS TO PEREGRINE BRAKES TO BRING IN TO LINE WITH 20/25 HP. Built to N.Sch. we have :- Peregrine 220 Direct + 193 S to rear + 301 S to front. 20/25 HP. 377 " + 220 S to rear + 304 S to front. (S= Servo multiplication of Torque) The angular movement of the scissor lever is 1.2 x on Peregrine the 20/25HP figure for a given movement of the rear shoes. The relative brake areas are :- 20/25 HP. Peregrine. Rear 88 sq.ins. 95 sq.ins. 88 sq.ins./ton 130 sq.ins./ton For the same period between adjustment as the 20/25 HP The direct braking should be on Peregrine : 377 x 130/88 = 550 units. The lever ratio of servo to direct should be :- 524/377 x 1/1.2 = 1.13 . . . Servo braking must be 550 x 1.13 = 622 S units. To get 45% front braking this should be split up into 400 S to front and 220 S to rear. To get these braking units we must :- (1) Alter 2.750 lever G.100533 to 3.14 (2) " 1.625 levers G.100528 to 1.23 | ||