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).
Phantom III gearbox lubrication test.
| Identifier | ExFiles\Box 94\2\ scan0231 | |
| Date | 11th May 1937 | |
| To HPS.{Horace Percy Smith - Experimental Factory Mgr} from W.Bell. c. to Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} 328 HPS{Horace Percy Smith - Experimental Factory Mgr}/WB.{Mr Brazier/Mr Bell}1/CB.11.5.37. PHANTOM III GEARBOX LUBRICATION TEST. N. Sch. 4690. Previously when tests were carried out with an oil scoop fitted to the second motion shaft - see Hs{Lord Ernest Hives - Chair}/WB.{Mr Brazier/Mr Bell}34/KW. 13.12.36 - it was found that oil was not fed to the third motion shaft bush below an engine speed of 1,500 R.P.M. With NS.{Norman Scott}4690, which consisted of holes drilled between the teeth of the first motion shaft gear, through which it was intended that the oil picked up by the second motion shaft gear teeth would be pumped through to the third motion shaft bearing bush, it was found that practically the only oil finding its way through to the centre of the first motion shaft was that which could be held by the teeth of the second motion shaft gear when the shaft was stationary, this being pumped through in the first few revolutions, after which the flow ceased. This was proved by draining the box and then pouring the oil at 30°C back into it, whilst running at 500 E.R.P.M.; there was not any delivery into the centre of the shaft. Tested over a speed range of 500 to 3,500 E.R.P.M. with cold oil (30°C) the general result was that occasionally a minute quantity of oil would find its way through between 800 and 2,000 R.P.M., but this was by no means certain. Using oil at 100°C, none entered the first motion shaft either when starting up with the box filled to normal level, or pouring the oil into the box after starting up. Therefore this scheme does not link up with the scoop scheme in the manner desired, but only provides initial lubrication to the bush. W. Bell. | ||