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).
Report comparing Delco, Bosch, and Lucas dynamos, focusing on features like control brushes and thermostats.
| Identifier | WestWitteringFiles\W\May1931-August1931\ Scan014 | |
| Date | 6th May 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Pgt. c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} Ev.{Ivan Evernden - coachwork} Hs{Lord Ernest Hives - Chair}/Pgt2/ADL6.5.31 ORIGINAL DYNAMOS GENERAL. X6099. In considering dynamos, we suggest that at all times we ought to keep ourselves up-to-date as regards the development, by keeping in touch with the following makes:- Delco - for U.S.A. Bosch - as Continental example. Lucas - as the most widely used British example. We recently reported on Lucas dynamos (see EFCl/AD30.3.31). The features we are interested in on the Lucas machine is the very narrow control brush. This is only .100" in width. We think this is a feature worth trying out on our own machines because we know any variation in the bedding of the control brush will quickly upset the output of the machine. We have recently obtained a Delco dynamo. This, unfortunately, is a 6 volt machine and cannot be compared directly with our own dynamos. The interesting feature on the Delco is the use of a bi-metal thermostat fixed to the carcase of the machine which, when the dynamo rises to 58°C., contacts break and insert resistance in the field circuit. The U.S.A. restrictions on head lamps are such that they do not have to struggle for big output from their machines. We have heard from Cy. that Cadillacs have been using the Delco generators with bi-metal thermostat for 10 years. This is also now fitted to the Buick and is described in the service book on the Buick with which Hs.{Lord Ernest Hives - Chair} sent to W.W. Therefore, the only interesting feature on the Delco is the thermostat control. With regard to the Bosch, we have already reported on the general characteristics of their voltage control machine. We have heard, however, that Bosch is now making a third brush control machine. We are trying to get particulars of this. As regards the question of reducing the cost of our electrical units, this is not referred to in this report but we feel that a number of economies can be made without affecting the quality or reliability. He/C. A.{Mr Adams} Ignatt. | ||