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).
Letter discussing various gearbox configurations, speeds, and braking systems.
| Identifier | ExFiles\Box 55\1\ Scan130 | |
| Date | 23th January 1932 guessed | |
| 3. Synchro. mesh & use the main clutch for every change. The train I have schemed has 3 units for 4 speeds & reverse (usually 4 & sometimes 5) I can nearly do 4 speeds with 2 units but cannot yet see how to handle it. Three speeds can be done very beautifully with 2 units is the simplest thing I have known but I fear units over-fued for us. ✔ We also had for some years the idea of a two speed box of ordinary type. about 2nd & top only. with unit (epicyclic) as 2Y & 2X, but I am trying to get the complete train so it would be simpler to control. Wilson has 4 units against our 3 & he has. reverse brake with 4 times engine torque. I use 1st & 3rd speeds brakes. & thus have one brake & have on 3 acts = 2 times engine torque. I have simpler & more practical balanced brake. & better absorption. I hope to send drawings for this to Claremont Haynes Ho. this week end. but it is much work. P.T.O. | ||