Rolls-Royce Archives
         « Prev  Box Series  Next »        

Chart and table detailing brake system distribution and efficiencies for various servo torque multiplications.


Identifier  WestWitteringFiles\M\2April1925-June1925\  Scan128
Date  12th June 1925
  
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 DATA:
DRUM DIA. 13"
.5 CAM
3.35"
2.25"
1.35
13.0"
4.35"
1.187
1.350
2.00
2.150
4.00
4.875
1.850"
3.150
6.00
DRUM DIA. 14"
.43 CAM
2.50
2.30

CALCULATIONS:
DIRECT REAR BRAKING: 13/4.35 x 1.187/1.350 x 2.000/3.150 x 6/2.3 x 14P/1 x 2.5/.43 = 355 P.
SERVO REAR BRAKING: S 13/4.35 x 1.187/1.350 x 1.850/1.750 x 4.875/8.000 x 2.150/3.150 x 213P = 249 S.P.
SERVO FRONT BRAKING: S 13/4.35 x 1.187/1.350 x 1.850/1.750 x 4.875/8.00 x 2.15/2 x 145P = 266 S.P.

TABLE: DISTRIBUTION FOR VARIOUS SERVO EFFICIENCIES.
Columns: SERVO TORQUE MULTIPLN, FOOT RATIO TO REAR, SERVO TO REAR, TOTAL TO REAR, SERVO TO FRONT, TOTAL BRAKING, % BRAKING FRONT, % BRAKING REAR.
- Row 1: 0, 355 P, 0, 335, 0, 335, 0, 100%
- Row 2: .25, 355, 62.3, 417, 66.5, 483, 13.7, 86.3
- Row 3: .5, 355, 124, 479, 133, 612, 21.6, 78.4
- Row 4: .75, 355, 187, 542, 199, 741, 26.8, 73.2
- Row 5: 1, 355, 249, 604, 266, 870, 30.6, 69.4
- Row 6: 2, 355, 498, 853, 532, 1385, 38.5, 61.5
- Row 7: 3, 355, 747, 1102, 798, 1900, 42, 58
- Row 8: 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/M9625.
Left Y-Axis: CONVENTIONAL BRAKING UNITS (0-2000)
Right Y-Axis: % BRAKING (0-100)
X-Axis: SERVO TORQUE MULTIPLN UNITS (0-4)
Graph Lines: TOTAL BRAKING, % REAR BRAKING, TOTAL REAR BRAKING, % FRONT BRAKING, SERVO TO FRONT, SERVO TO REAR.

STAMP:
ROLLS-ROYCE LTD.
PRINT ROOM
12 JUN 1925
DERBY
  
  
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).


Copyright Sustain 2026, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙