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 American Bosch Magneto ZR 6, comparing it to the German version.
| Identifier | ExFiles\Box 4\5\ 05-page062 | |
| Date | 20th July 1920 | |
| X 430 R.R.B'ham.100 T/P.O.Dat.24-5-20 C.H.W To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to Bn.{W.O. Bentley / Mr Barrington} c. to Cy. c. to Na.{Mr Nadin} c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Ey. Hs{Lord Ernest Hives - Chair}5/LG20.7.20. X.3916. PRELIMINARY REPORT ON AMERICAN BOSCH MAGNETO ZR 6. X.430. X.2375. Although this magneto is called ZR 6 type, it is in many ways different to the German Bosch ZR 6 Magneto, which we used on our cars before the war. The parts on this magneto are not interchangeable with the German Bosch ZR 6. The weight of the Magneto is 15.5 lbs. " " German ZR 6 is 18.4 lbs. " " Watford is 12.8 lbs. X.800. X.1819. The American Bosch Magneto is of the same dimensions as the German ZR 6 but as they use aluminium die castings instead of bronze, this accounts, for the difference in weight. It is in the high tension distributor that this American Magneto differs chiefly from the German ZR 6. A high tension carbon brush is fixed into an insulated holder to the larger gear wheel. The distributor is formed by having a high tension collecting ring and six segments suitably formed in a stabilite moulding. The high tension carbon brush has sufficient surface so that it rubs on the collecting ring and makes contact with the different segments as it revolves. We see nothing, against this form of high tension distributor, in fact, we think there should be less chance of pre-ignition with this form than with the usual ZR 6. Any carbon dust which is formed has a chance of falling away from the rubbing surface also centrifugal force does not increase the load of the | ||