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).
Change gear problems, discussing freewheel sideshafts, epicyclic 3rd speed gears, and patent applications.
| Identifier | WestWitteringFiles\T\March1929-December1929\ Scan018 | |
| Date | 7th March 1929 | |
| DA.{Bernard Day - Chassis Design} ) FROM R.{Sir Henry Royce} BY.{R.W. Bailey - Chief Engineer} ) (At Le CanadelHenry Royce's French residence.) HS.{Lord Ernest Hives - Chair} ) R4/M7.3.29. REC'D AT WW. 12.3.29. Copy to SG.{Arthur F. Sidgreaves - MD} (struck through) Copy to Mr. CLAREMONT X5310 X2061 X5640 CHANGE GEAR PROBLEMS. I shall be pleased to hear if our freewheel sideshaft for the 20HP. has gone to Derby, and whether it is being made. Also the position of the epicyclic 3rd. speed. This has not yet had a patent application. For instance the general arrangement of epicyclic next to engine, and two speed and reverse ordinary box has been covered by an earlier patent of ours, but we have recently done much work upon it, including the idea of spring loading the direct drive clutch, spring loading the 3rd. speed brake and using a toggle mechanism with piston operated by engine induction pipe vacuum, (by closing throttle), or any other source of fluid pressure, or direct by hand lever or pedal". The first (engine vacuum) will probably be used, and with this we have schemed valves and passages of special character to avoid otherwise objectionable phenomenon of leaky piston affecting carburation, and air cushioning at end of stroke to avoid noise. Can DA{Bernard Day - Chassis Design}/HDY.{William Hardy} sent to Mr. Claremont a diagrammatic drawing shewing all we can claim in the first place for an English provisional patent, until proved worthy. I send to Mr. Day my arrangement for the internal gear as I understand it in principle, and can be designed. It might be thought a good scheme to avoid heavy loads on plain bearings or as we thought a poor mechanical job. I was surprised to find how fortunate in some ways the scheme is. I have stated elsewhere that this device does not alter the ease of changing gear, but provides a very silent 3rd. speed, though of very doubtful life because of the difficulty of supporting the various units. I shall be quite pleased to receive from our specialised designers - Messrs Day and Hardy - any reports or suggestions on the subject, principally referring to our competitors. For instance I do remember discussing the synchronised mesh scheme referred to by Mr. Olley. R.{Sir Henry Royce} | ||