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).
Preliminary report on the B.T.H. type F.M.6 magneto, with comparisons to other magnetos.
| Identifier | WestWitteringFiles\F\February1921\ Scan93 | |
| Date | 10th February 1921 | |
| To R.{Sir Henry Royce} from EFC. c. to CJ. PN{Mr Northey}: <s>c. to E.{Mr Elliott - Chief Engineer}</s> <s>c. to PN.{Mr Northey}</s> c. to Bn.{W.O. Bentley / Mr Barrington} By c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to Da.{Bernard Day - Chassis Design} & P. <s>c. to By</s> c. to EWT. for R.R.Inc. ORIGINAL. X.3515 - B.T.H. TYPE F.M.6 MAGNETO & AND OTHER MAGNETOS. Please find attached copy of my assistant's preliminary report on the new B.T.H. type F.M.6 magneto. It will be noticed that this magneto has movable pole shoes in the form of a sleeve working in the fixed pole shoe tunnel. A disadvantage of the movable sleeve such as is fitted to the Watford type E.O.6 magnetos is that the magnetic reaction of the revolving armature vibrates the controls. This effect must be decidedly lessened, if not obliterated, in this B.T.H. magneto by the fact that the working surface of the moving pole shoes is the inside hollow itself of the fixed pole shoes. The Experimental Dept. will shortly be sending down to Mr. Royce by car a case containing four magnetos, each set out in parts on a board, so that all the details of these four magnetos can be examined with ease. The four magnetos to be sent are :- (1) R.{Sir Henry Royce} Bosch Z.R.6. (2) U.S.A. Bosch Z.R.6. (3) Watford E.O.6 with movable sleeve. (4) B.T.H. F.M.6 with movable pole shoes One or two further points about design may be here recorded. Contd. | ||