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).
Development of a dimming switch and dipping headlamps for the 20.HP model.
| Identifier | ExFiles\Box 61a\1\ scan0183 | |
| Date | 5th September 1923 | |
| TO R.{Sir Henry Royce} FROM DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} c. to LHS.{Lord Herbert Scott} c. to HS.{Lord Ernest Hives - Chair} c. to BY.{R.W. Bailey - Chief Engineer} x4291 RE. 20.HP. HEAD LAMPS. x4555 We understand from Sales that it is required to fit a dimming switch on the 20.HP. headlamps similar to that which we now fit to the 40/50. It appears essential that we should have something to fit to stop cars and to offer customers, and so far this is all we have, therefore we are writing Sales and asking them if they can find a place on the instrument board on the off-side of the switchbox. At the present moment Messrs Barker's (Coach-builders) are supplying and fitting dipping head lights to a number of our cars at a cost of from about £8 to £10 per set. Whilst the results are effective the actual mechanism is mechanically bad and heavy to oper-ate. We think it would be nice if we could offer cus-tomers a R-R scheme of dipping head lights at a suitab-le price. We have had some sort of a scheme of dip-ping head lights on 4.G.11. for nearly a year, and we are asking Derby to make several small modifications to this scheme by adapting it for the larger lamps, weaken-ing the spring on the lamps, and preventing the flying back of the hand control against it's stop and making a noise. We also think that the necessary and most de-sirable angle of dip should be ascertained. Sketches of these improvements will be sent to Derby in a few days and we think then that they should experiment and report on dipping head lights with a view to being able to come to some decision. The tilting of the side-lights to 5° does eliminate their glare to some extent but one cannot af-ford to entirely switch off ones sidelights, and there-fore one asks to be able to either dim or dip them, and the latter seems preferable. DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} | ||