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Schematic of modified brake levers with a corresponding chart analyzing braking distribution and efficiency versus servo torque.


Identifier  ExFiles\Box 57\1\  Scan155
Date  15th June 1925 guessed
  
INDIA(Production 20 HP. with 4-speed box and Front Wheel Brakes)
HS {Lord Ernest Hives - Chair} 4/LG 20525 AS MODIFIED BY N.SCH 2005 & DAI/M 9625

DIAGRAM:
DRUM DIA. 13
.5 CAM
DRUM DIA. 14
.43 CAM

CALCULATIONS:
DIRECT REAR BRAKING (13/4.35) (1.187/1.350) (2.000/3.150) (6/2.3) (2.5/.43) 14 P. = 355 P.
SERVO REAR BRAKING S.(13/4.35) (1.187/1.350) (1.850/1.750) (4.875/8.000) x (2.150/3.150) x 213 P = 249 S.P.
SERVO FRONT BRAKING S.(13/4.35) (1.187/1.350) (1.850/1.750) (4.875/8.00) (2.15/2) x 145 P = 266 S.P.

TABLE: DISTRIBUTION FOR VARIOUS SERVO EFFICIENCIES.
| SERVO TORQUE MULTIPLN | FOOT RATIO TO REAR | SERVO TO REAR | TOTAL TO REAR | SERVO TO FRONT | TOTAL BRAKING | % BRAKING FRONT | % BRAKING REAR |
| --------------------- | ------------------ | ------------- | ------------- | -------------- | ------------- | --------------- | -------------- |
| 0 | 355 P | 0 | 335 | 0 | 335 | 0 | 100% |
| .25 | 355 | 62.3 | 417 | 66.5 | 483 | 13.7 | 86.3 |
| .5 | 355 | 124 | 479 | 133 | 612 | 21.6 | 78.4 |
| .75 | 355 | 187 | 542 | 199 | 741 | 26.8 | 73.2 |
| 1 | 355 | 249 | 604 | 266 | 870 | 30.6 | 69.4 |
| 2 | 355 | 498 | 853 | 532 | 1385 | 38.5 | 61.5 |
| 3 | 355 | 747 | 1102 | 798 | 1900 | 42 | 58 |
| 4 | 355 | 996 | 1351 | 1064 | 2415 | 44 | 56 |

GRAPH:
TITLE: INDIA(Production 20 HP. with 4-speed box and Front Wheel Brakes)
ORIGINAL BRAKE LEVERS AS IN HS {Lord Ernest Hives - Chair} 4/LG20525,
ALTERED AS PER N.SCH 2005 & DAI/M 9625.
LEFT Y-AXIS: CONVENTIONAL BRAKING UNITS.
RIGHT Y-AXIS: % BRAKING.
X-AXIS: SERVO TORQUE MULTIPLN UNITS.
LINES: TOTAL BRAKING, % REAR BRAKING, TOTAL REAR BRAKING, % FRONT BRAKING, SERVO TO FRONT, SERVO TO REAR.
  
  
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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