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).
Distributor head sparking and corrosion, comparing the standard rotor to a 'mushroom' rotor and suggesting a redesign with vanes.
Identifier | ExFiles\Box 32\5\ Scan064 | |
Date | 22th October 1927 | |
Contd. -2- EFCl/T22.10.27. When sparks jumped from the sparking points in the distributor head, to the base, they were observed occasionally to traverse part way on the distributor head surface en route as shown :- SPARKING POINT DISTRIBUTOR HEAD BASE This effect might cause tracking if the surface of the distributor became moist or conductive." Another result we have reported is that the mushroom rotor does not appear to prevent the development of corrosion inside the distributor head appreciably more than the present rotor. As a result of this, we have suggested that a mushroom rotor be provided with vanes in such a way as to cause a definite impelling effect of the air in the distributor head. It will be remembered that it is always considered that the standard rotor acts as an air impeller, whereas in this mushroom rotor we simply have a solid of revolution which exerts no impelling effect. Before putting these rotors on an experimental chassis for a 10,000 mile test, may we suggest that it should be considered as to whether it is feasible to re-design this rotor in a form which is provided with vanes. Judging from the results of the report it would appear that on open circuit tracking would occur either on the rotor edge or on the distributor head, but that it would not be serious enough to put the apparatus out of action when the short circuit was removed, as in the case of the present rotor which, when once it tracks, is done for. ST.{Capt. P. R. Strong} DFC. | ||