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Comparative table of servo and brake particulars for 40/50, 20/25, and Peregrine car models.


Identifier  ExFiles\Box 1\10\  B001_X106 TO X 110-page011
Date  7th November 1932 guessed
  
SERVO AND BRAKE PARTICULARS

COLUMN HEADERS: 40/50, 20/25, PERE: PEREGRINE(Experimental Bentley car never produced / Aero Engine)
SIDE NOTE: S = TORQUE MULTIPLICATION

CAR WEIGHT: 48 CWT, 35 CWT, 28 CWT

BRAKE UNITS FROM SERVO BRAKING:
R: 272 x S, 220 x S, 193 x S
F: 227 x, 304 x S, 195 x S

SERVO TORQUE MULTIPLICATION:
FORMULA: = 2/μ [FABRIC COT λ / (1 + CAM)]
FOR μ = .2: 2.53, 1.55, 1.28

TAKING INTO ACCOUNT ROAD WHEEL DIA.

BRAKE UNITS PROP. TO: 38, 26, 17, 20

FOR SAME DECELERATION

PEDAL PRESSURE REQUIRED: 100, 106, 130, 110

END THRUST ON SERVO: 1030, 742, 1030, 815

AREA OF SERVO LINING: 12.2, 8.7, 5.5, 7.45

UNIT PRESSURE (P): 85, 85, 188, 121

RUBBING VEL FOR SAME CAR SPEED

PROPORTIONAL TO (V): 5, 5.7, 5.6, 6.45

PV: 42.5, 48.5, 105 (SIDE NOTE: HEATING PROP. TO THIS)

LINEAR MOVEMENT OF SCISSOR LEVER

FOR 1" MOVEMENT OF REAR BRAKE CAM: .83, .57, .59, .57

ANGULAR MOVEMENT: 4.05, 3.23, 3.95, 4.05

NOTCH ADJUSTMENT: 5°, 6°

ANGULAR MOVEMENT OF SCISSOR LEVER FOR 1 NOTCH: 20.3°, 15.4°
  
  
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).


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