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).
Engine vibration, a novel piston design, and a throttle valve alteration to stop silencer explosions.
| Identifier | ExFiles\Box 25\3\ Scan048 | |
| Date | 22th April 1912 guessed | |
| (7) piston of correct weight but without tops. If the engine vibrates at 2000 revolutions without any gas pressure, then the cause is most likely due to this variation in kinetic energy as mentioned earlier, and could be reduced (a) by reducing the weight of the pistons and connecting rods, (b) by lengthening the connecting rods. By method (a) the crankshaft vibrations can be reduced. This has been proved to be specially noticeable in connection with engines without slipper flywheels, and for which these light pistons are particularly desirable. Although (b) reduces the variation in the kinetic energy, and, therefore, uneven resistance to turning at high speed, it will have no benefit on crankshaft vibrations. I am sending to the Works tomorrow a novel design of piston in which lightness, I hope, may be carried to extreme limits without the piston suffering any practical distortion by explosive pressure. Also while Mr Bailey has been here, we have sent in a sketch of a suggested alteration to the throttle valve to stop silencer explosions. This is so simple and I feel sure will be effective that I stopped all experiments or discussions on previous suggestions I had made. Although it seemed only the work of a few hours to test, we have never heard a word of receipt or comment from the Works. F.H.Royce. | ||