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).
Comparison of the construction and materials of R. Bosch, U.S.A. Bosch, and Watford magnetos.
| Identifier | WestWitteringFiles\F\February1921\ Scan94 | |
| Date | 10th February 1921 | |
| R.R. 285A (100 T) (S.H. 798 10-12-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2947 Contd. 2- EFC2/T10.2.21. R.{Sir Henry Royce} Bosch Z.R.6. X424 Both pole shoes are solid and the armature core is laminated. The distributor pinion wheel on the armature is made of polished black fibre, similar in appearance to ebonite, whilst the distributor gear wheel is apparently of cast iron and fitted with a damper ring. A lubricating wick is provided for the bearing of this wheel. U.S.A. Bosch Z.R.6 X.3916 The armature is a little shorter than that of the R.{Sir Henry Royce} Bosch Z.R.6. The pole shoes are solid, so also is the armature core as far as can be ascertained. The distributor gear wheel is made of gun-metal and has an aluminium damper ring riveted to it. It is mounted in a plain bearing lubricated by means of an oil wick. Watford E.O.6. X.4181 The E.O.6 magneto referred to above, the parts of which are being sent for inspection, is one of the later type E.O.6 recently received. Previous reports on the E.O.6 have referred to the earlier type E.O.6. The principal difference is that the later type is provided with a much bigger range, viz. about 55° instead of 35°. The pole shoes which are solid are cast in a framework of gun-metal and the working face of the pole shoe is much smaller in the modified E.O.6 than in the earlier model. The distributor gear wheel of both types is composed of a gun-metal ring fitted to an aluminium frame and is mounted on two ball bearings. EFC. | ||