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).
With a sketch proposing a simpler, stiffer gearbox coupling design to mitigate torsional vibration issues.
| Identifier | WestWitteringFiles\L\Jan1924-March1924\ Scan95 | |
| Date | 19th February 1924 | |
| TO MR. START. MR. ELLIDGE. [crossed out] FROM R.{Sir Henry Royce} SECRET. E.A.C. IV. Copy to MR. DAY. MR. WARD. MR. HS.{Lord Ernest Hives - Chair} COUPLING TO GEARBOX. [Handwritten]: X4604 VPRO X634-X9310 Naturally flexibility between the flywheel and gearbox may permit of a period of torsional vibration as on the present Retard at 40.MPH. Will you therefore see that the coupling and shaft for the above is sufficiently stiff which we scarcely can pre-determine with certainty, or is so designed that the stiffness can be increased if found necessary. Sometimes I think the whole central portion of the transmission vibrates torsionally which would include the gearbox gears, two bevels and the differential, and sometimes I think it may be the universal joint and sleeve drum. This is what might be called the central portion of the longitudinal shaft. The arrangement on Lec. 1822. seems OK. but it really does seem a pity to add 2 joints, one small dia. serrated, and one cone and key for the sake of the small movement there may be, but as it seems necessary to have a large shaft, and with a large shaft could we do without one joint - see sketch, which shows a simpler and simpler arrangement, to let Derby have something quickly. [Diagram annotations]: This large as possible but just passes up hollow tube. serrated or cone. solid Dia. much larger than shown on Lec.1822. increase this probably greater movement here than here At least could you give an alternative to test. The above would be simple and torsionally stiff. R.{Sir Henry Royce} G | ||