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).
Blueprint showing a cross-section of a 4-speed gearbox and its gear layout.
| Identifier | ExFiles\Box 137\5\ scan0077 | |
| Date | 17th April 1929 | |
| DRAWING NO. SK 315. SEE ALSO THE FOLLOWING OPERATION DRAWINGS MOVEMENT OF GEAR LEVER R 3 1 2 4 DOUBLE HELICAL 16 P. ABOUT 45° HELIX ANGLE HIGH 3RD 2ND 16P 12P 40T 30T REVERSE EMERGENCY LOW HYATT PILOT BEARING 30T 50T 40T 30T CENS APPROX. 3 1/2" SEE C APP 17 1929 AP 17 / 29 DRAWN BY: QY TRACED BY CHECKED BY APPROVED BY LIMITS DATE: AP 17/29 ROLLS-ROYCE OF AMERICA, INC. MODEL SEC WEIGHT SCALE BRINELL HEAT TREAT STANTON TITLE: 4-SPEED GEARBOX MACHINE ALL OVER MACHINE WHERE MARKED III MATERIAL SPECIFICATION NO. OFF | ||