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).
Required alterations to the 40/50 and 25 HP gearboxes, referencing Dr. Maybach's designs.
| Identifier | Morton\M19\ img127 | |
| Date | 2nd March 1931 | |
| COPY. TO R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson}14/KT.2.3.31. c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} X. 7310. c. to Sg.{Arthur F. Sidgreaves - MD} X. 5310. X. 523. R.R. EASY CHANGE SILENT GEARBOXES. ---------------------------------- In view of the information obtained from Dr. Maybach, it appears that we require some alterations to the existing designs at present being made. (1) 40/50. The fact that we cannot have a neutral position with the Maybach dogs does not affect the change for the silent epicyclic third on this box, because it is not designed to have a neutral position. The change to obtain the two silent lower gears easily, however, will have to be altered because it is essential that a neutral position shall be available and such a position is unattainable with Maybach dogs. If we turn this set of Maybach dogs into a normal dog change with direct operation from the gear lever, the neutral difficulty will be recovered and we shall have a gearbox that will give us a silent easy change third, and a silent second and first but without an easy change for these lower gears. (2) 25 HP. This box being designed so that it relies on the Maybach dogs having a neutral position if the lower gears are to be operateable, it will either be necessary to dispense with the easy change or re-design the box so that the Maybach dogs can be incorporated without a neutral position. Of course we may find, on the small car, that a straight dog clutch can be made to give a relatively easy change, but experiments we have made on the 40/50 have not so far been very successful. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||