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).
Design and testing report for a dynamo drive on a Kestrel K.II M.S. 93 engine.
| Identifier | ExFiles\Box 178\4\ img070 | |
| Date | 31th May 1932 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Yng. c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} c. Rg.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. Fv. EP.{G. Eric Platford - Chief Quality Engineer} Hs{Lord Ernest Hives - Chair}/Yng.1/AD31.5.32. KESTREL DYNAMO DRIVE - DES.1661 ENGINE K.II M.S. 93. A dynamo drive to the above scheme has been designed to meet the demands which are now being made for an engine driven dynamo on aircraft to supply current for such items as navigation lights and wireless. The scheme is only applicable to supercharged engines. Sketch 1. illustrates how the drive is taken from the large gear of one of the supercharger intermediate gears so that the dynamo is driven through the slipper pads of this gear. The gearing is arranged to give a speed increase on the engine R.P.M. of 2.24/1. A flexible cable type drive transmits the torque to the dynamo since it is not possible to mount the latter in such a position as to be driven direct due to the position of the rear engine foot. Kestrel II.MS. 93 has been used for the tests in conjunction with the following electrical equipment :- R.A.E. Mark IV 1000 watt (15v - 70 amp.) generator. " II Dynamo electric regulator. " I Accumulator cutout. Diagram II shows the wiring system and the photograph A the complete apparatus rigged up on the test bed. This photograph illustrates the dynamo mounted at the rear of the engine and driven from the rear side of the gear case. It was necessary to use this arrangement since the only dynamo available was of the opposite rotation to the one which will normally be used. Photograph B. shows the arrangement which was used after the failure of the flexible drive. The dynamo was mounted in line with the axis of the drive from the supercharger and a short coupling carried on Hardy discs replaced the flexible drive. Cooling of the dynamo was effected by means of an air blast from a small fan of the Keith type which gave an air speed of 126 M.P.H. over the dynamo. TESTS CARRIED OUT. The tests carried out consisted of :- (a) Initial 2 hrs. test for acceptance purposes. (b) Endurance Test. | ||