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).
Note on the elastic mounting design for the 'Eagle' engine's electrical starting gear.
| Identifier | ExFiles\Box 180\M2\M2.1\ img013 | |
| Date | 26th January 1918 | |
| To By.{R.W. Bailey - Chief Engineer} from P. C. to WH. C. to HFC. X.3174 X.3161 X.3247 Re - "Eagle" Electrical Starting Gear. ORIGINAL. RECEIVED 26 JAN 1918 Please find attached to Mr. Bailey's copy of his note drawing Lec.886, showing method of holding both Lucas and C.A.V. motors on the "Eagle" engine for the electrical starting gear. We have not fixed the motor rigidly to the engine since it would then have to vibrate in a manner coincident with the movement of the engine which would, we think, throw a load on to the motor. The design shown is intended to provide an elastic mounting. The horizontal shaft at the top will give in bending moment in any direction and the anchorage at the bottom consisting of a flat steel plate is flexible vertically. We think that the flat side of the lower half of the crankcase to which the steel plate is anchored will give under load and provide some limited horizontal elasticity at the bottom point by which the motor is fixed. This latter effect is not essential however, since the motor is still held elastically in a horizontal direction owing to the lateral flexibility of the top mounting. Since we have the mass of the motor supported on a flexible base it will have a periodicity of its own. This periodicity we expect to be well above the periodicity of the vibration on the engine which tends to swing the motor. The centre distance of the bearer of the supporting tube on the engine may be varied to what particular dimensions | ||