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).
Dynamo options and a vibrator control system for the 25HP model.
| Identifier | ExFiles\Box 163\6\ img196 | |
| Date | 14th July 1932 | |
| E.{Mr Elliott - Chief Engineer} FROM R.{Sir Henry Royce} x6016 R2/M14.7.32. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} DA.{Bernard Day - Chassis Design} 25HP DYNAMO. X.6005 X.8092 Referring to your E1/HP9732, we must never forget the fact that changes of standard cause the Administration trouble, especially in connection with spare parts, abroad and at home, so that alterations should be made rarely, and in sufficiently large number, to constitute a definite improvement to the type. Therefore the following points present themselves: (1) I should not consider for a moment the use of the P.2. dynamo on the present 25HP. (2) We should not, if possible, change the present dynamo on the 25HP. until we introduce either J.1. or J.3. (3) You will remember that for years I have been pressing for vibrator control, pointing out that it would clear up so many complications and disadvantagesof the present control, and to a sufficient extent automatically adapt itself to all conditions of the overcharged and other battery conditions. If pressed for an immediate move one would feel that this vibrator control fills the book better and simpler than anything else. It should be soon available as we have several working on cars. I understar that its reliability is the only point requiring proving. So far as I remember we have never been troubled with overloading the dynamo to the extent of damaging it with heat, and should we decide that we cannot use the vibrator control I think that the 3 stage sch. is quite a passable move. It is understood that one stage is taken care of automatically by the coming in of the headlamps which controls that section of the resistance, and that the charging switch controls the other two sections, the result being that the present 'no charge' is a very small charger known as 'summer daylight', the present fully charged position is 'daylight maximum', and this with the headlamps on would be the maximum, and could be arranged to almost roast the dynamo in hot sunny weather, as it would only be during the cool of the evening, or at night. One feels that both these schemes require certain modifications to the dynamo as well as the connections. If it is possible to use the dynamo in either of these ways without modifications then it would seem that one is instantly available without seriously affecting the spares. R.{Sir Henry Royce} | ||