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).
Visit to Cambridge Engineering Laboratory regarding research on crankshaft torsion tests and electrical methods for detecting vibrations.
| Identifier | ExFiles\Box 6\1\ 01-page133 | |
| Date | 1st May 1928 | |
| To R.{Sir Henry Royce} From ns{Norman Scott}/Tan. c. to AJ. Hor. c. to MS. E.{Mr Elliott - Chief Engineer} c. to EA. BY.{R.W. Bailey - Chief Engineer} X 5010 HS{Lord Ernest Hives - Chair}/Tan/LGS.5.28. VISIT TO CAMBRIDGE RE. CRANKSHAFTS. X.684 X.6010 X.2442 X.1292 X.5010 Considerable research work on the above subject is being done for the Air Ministry at the Cambridge Engineering Laboratory. This consists principally of: (1) A lot of torsion tests of crankshafts, mostly aero, in and out of bearings. (2) An attempt at producing torsional vibrations in the crankshaft of a stationary (i.e. not rotating) aero engine by means of electrical excitation. Tan. paid a visit to the lab. to discuss crankshaft problems in general, and in particular to get information on the method used for electrical excitation of crankshaft vibrations. It is not easy to discover in an aero engine when running the precise speed of torsional vibration. We have made attempts to use the Summers Torsional Indicator [strikethrough]Vibrograph[/strikethrough] but this device failed owing to constant small [strikethrough]throttle[/strikethrough] fluctuations in the running speed of the engine. A complicated torsiograph has been invented by some people at Farnborough. It depends for its indications on measuring the variation in twist in a long hollow propeller shaft, and is thus best adapted for use in direct drive or air-cooled radial engines. We are anxious therefore to find a simple electrical method of ascertaining the crankshaft frequency. The preliminary experiment at Cambridge has not been very satisfactory as the tests showed a contd :- | ||