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).
Testing a disc crankshaft for a 20 HP engine.
| Identifier | ExFiles\Box 25\3\ Scan117 | |
| Date | 20th February 1924 | |
| H.R. 493A (40 H) (SL 42 12-7-23). J.H. D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. Expl. No. 4221 634 4604 REF: Hs{Lord Ernest Hives - Chair}2/LG20.2.24. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. RG.{Mr Rowledge} c. to E.{Mr Elliott - Chief Engineer} BY.{R.W. Bailey - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} PN.{Mr Northey} DISC CRANKSHAFT FOR 20 HP. We have been running a 20 HP. engine on the test bench fitted with the disc crank. Under standard conditions the engine could be run up to 3200 R.P.M. without excessive vibration. We have run the engine without the slipper wheels at the front end. Under this condition we get a distinct crankshaft period between 1500/1600 R.P.M. and another at 2100 R.P.M. - this latter one being slight. The crankshaft periods without the slipper wheels appear to be of less intensity than we obtain on the standard engines. We shall shortly be fixing this engine into a chassis and will report on its behaviour. There is no doubt that the increased bearing area will be a definite advantage on this engine. The weight of this crankshaft is 61 lbs. compared with 29.5 lbs. for the standard. RG.{Mr Rowledge} has suggested that after we have obtained an accurate impression of the crankshaft, the webs might be made thinner. At present the webs are .500 compared with .475" on the Hispano. We are now running the Hispano engine on the test bench - there are no definite periodic vibrations of the crankshaft but by the sound and feel, there is torsional deflection contd:- | ||