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).
Request for detailed specifications on Bosch car lighting dynamos, specifically third brush controlled models.
| Identifier | ExFiles\Box 60\4\ Scan052 | |
| Date | 7th May 1931 | |
| X4562. Hs{Lord Ernest Hives - Chair}/CAP2/AD7.5.31. 7th May, 1931. Messrs. J.A. Stevens Ltd, Upper Rathbone Place, London, W.1. Dear Sirs, We should be pleased if you would supply us with details of any Bosch car lighting dynamo you may have of a type suitable for a fast high-powered touring car. In particular, we are interested in third brush controlled machines, as our impression is that this type is in more general use in this country and America. It would greatly assist us if, in any information you supply concerning a machine of the third brush type, you could arrange to include the following :- (1) The speed at which the machine puts up an open circuit voltage of 14.0 at the terminals when in the hot condition. (2) The maximum output at a terminal voltage of 14.0 and the dynamo speed at which this occurs with the machine still in the hot condition. (3) The output at a speed of 4,000 R.P.M. again at 14.0 volts and with the machine hot. In connection with these observations we should like you to state the carcase temperature of the machine when it is in what you consider to be the hot condition. | ||