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).
Technical drawing and description of a 2-speed unit preselector self-changing control for synchro-mesh gears.
| Identifier | ExFiles\Box 136\4\ scan0138 | |
| Date | 16th February 1937 guessed | |
| 2-SP.{Mr Spinney} UNIT [Drawing Labels] Gear Striking Lever Stop Shift Fork 3rd N 2nd Selector Shaft Peg Cam Coupling Pawls (Shaded) Self-change Shaft PRESELECTOR self-changing CONTROL - for Synchro-mesh Gears. The arrangement shown in the above rough sketch differs from the other constructions by having the Peg on the Shift Fork instead of on the Striking Lever. The one Peg serves two purposes. It operates in much the same way as in the other arrangements and makes a compact form of the mechanism that is very suitable for the smaller sizes of 3-sp.{Mr Spinney} and 4-sp.{Mr Spinney} gears. The sketch shows the extremely simple and robust character of the mechanism. For heavy duty change-speed gears there is yet another arrangement of the mechanism that provides an easy control for four or five forward speeds, with either one or two reverse gears. | ||