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).
Plunger piston design, focusing on oiling, piston rings, and a proposed sylphon tube fitting.
| Identifier | ExFiles\Box 41\4\ Scan005 | |
| Date | 1st December 1919 | |
| R.{Sir Henry Royce} R.{Sir Henry Royce} 235 A (100 T) (S-F 846 6.8.19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460 X.3746 R8/G8.12.19. To EH. from R.{Sir Henry Royce} Copy to CJ. " " BN.{W.O. Bentley / Mr Barrington} " " DA.{Bernard Day - Chassis Design} " " HS.{Lord Ernest Hives - Chair} £ X.3746. RE PLUNGER PISTONS. Surely it is necessary to have some oil on the pistons, and that the quantity that would escape past the little plunger is fitted by three good rings, would not be sufficient to overoil the cylinders, especially if the oil were only admitted intermittently, which I believe will be found to do the work quite well, unless the plunger is leaking. I want you to take care that the piston rings used on the little pistons are well fitted, especially does this apply to having the outside lapped in a cylinder of the same size, the reason being that theends of the rings are very stiff unless they naturally conform to the curvature of the cylinder they cannot possibly bed. X.3742 We are sending you a design embodying the fitting of the sylphon tube. We do not expect to use these as they are too costly, but would be a means of ascertaining where the oil leaks arise. They would naturally need solder in their constructione, which might not stand the heat, and if you will need some slightly different construction of the sylphon tube. R.{Sir Henry Royce} It will be advisable to also test if the scraper ring at the bottom makes very much difference. | ||