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).
Typed letter discussing modifications to piston design, including the use of springs and scraper rings.
| Identifier | ExFiles\Box 35\2\ scan 176 | |
| Date | 22th December 1919 | |
| Contd. x.3776. -2- R1/G22.12.19. We have lately thought that if a piston could be made to collapse on emergency, being sprung out by a steel spring against a stop which could be adjusted, one would get a scheme which is hopeful, the idea being that one steel is not likely to lose its elasticity. x.3765 We also believe that the oil piston plunger might be profitably supplemented by a steel spring, say, of 20 to 40 lbs effort, with intermittent oil, i.e. oil which is shut off on the top of the stroke, the spring would induce the oil to get in when it would be trapped from getting out, and a fairly oil-tight plunger would prevent the piston leaving the power wall. We cannot understand how the oil from the plunger piston can do any harm with an effective scraper ring. We hope to send you another plunger piston where an open scraper ring is above the plunger and should be more effective. We have asked if a stiffer or wider ring is more effective. I have not heard which cast iron piston which we have used in the past is considered the best. R.{Sir Henry Royce} PSSS 2 (6179) 250 J N 11 G81 V PSS H M | ||