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).
Report page investigating vehicle vibration, propeller shafts, and suspension issues.
| Identifier | ExFiles\Box 148\4\ scan0155 | |
| Date | 13th September 1940 | |
| -2- Cont'd.{John DeLooze - Company Secretary} 10 ft. 4 ins. 10 ft. 10 ins. 11ft. 1 in. 8. Insert of parallel incentre of frame cross 0 6 ins. 9 ins. 9. Wheels and tyres. 6.500 x 16 7.0 x 16 7 x 16. *Actually the prop. shafts of the long wheelbase cars are 1.000" the longer, according to Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager} This may be due to the two types of semi floating rear axle. We will deal with the items in order. 1. The moving propellor shafts are materially the same length and cannot effect the issue. 2. We suspect a matching of torsional frequencies in the transmission as accounting for the 55 m.p.h. vibration, and suggest a mathematical investigation to see if the variation in the length of the fixed prop. shafts can account for this. 3 & 4. The observations under heading 2 also apply to the axle shaft lengths and diameters. 5 & 6 Ev.{Ivan Evernden - coachwork} will investigate the relative pumping between 50.000 and 56.000 rear springs. Mr. Daniell, during his visit was very insistent that experiments on Wolseley and Morris cars had shewn that pumping can be a cause of the trouble but could not explain why. 7. The engine type can play no real part as on the 10 ft. 10 in. wheelbase we have both 8 cyl. and 6 cyl. units. 8. There is a difference in the cross centres, but at the moment we cannot see how the change in rigidity of this portion can have any effect on the case. 9. We shall investigate the relationship of the various natural wheel frequencies on the road, in connection with our search for matched frequencies. There are three further points which we feel worth mentioning - a.{Mr Adams} Mr. Daniell, during his visit, was emphatic that if the elastic support of the centre bearing had not uniform elasticity concentric with the shaft, the troubles we are experiencing will arise. He quoted. Cont'd.{John DeLooze - Company Secretary} | ||