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).
Alteration of a switchbox, including the new position functions and wiring considerations for the Klaxon horn.
| Identifier | ExFiles\Box 45\4\ Scan364 | |
| Date | 17th December 1923 | |
| SECRET. To EFC. from R.{Sir Henry Royce} c. CJ. BJ. RG.{Mr Rowledge} c. E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} PN.{Mr Northey} X4081 E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. R4/M17.12.23. SWITCHBOX. X.9730. X.4081. For EAC.1 & LI and probably for Goshawk we are altering the switchbox in the following way - On the L.H. side it still remains as at present but with slight modifications to the dimensions so as to obtain a fourth position on the right hand side. The fourth position on the R.H. side will then be arranged so that bottom is 'off', No.2 'battery ignition only', No.3 'battery, magneto and charge', No.4 'magneto only and charge'. The fourth position is to permit of proving whether the battery (magneto ?) ignition is right, and also for running with economical current, that is, when the current is low we may desire to save the battery ignition current. We are afraid this will affect the moulding and a number of pressed tools, but it will not affect any- thing else seriously. The economy both of connections and complication will be vastly superior to a separate switch. It is assumed with this position that for the Goshawk, when there is no battery fitted, the central dynamo wire will be disconnected from the dynamo so that we can run on magneto without charging. It is also necessary when the battery is connected and we desire to run on the magneto, to insulate the primary wire on the battery ignition tower, for which we are providing an insulated terminal. It will be noticed that with this arrangement we shall be obliged to continue the use of the double wire to the Klaxon press button or be content to leave the Klaxon alive, with the risk of blowing the fuses when detaching the wires or making any chance electrical earth contacts on any part of the Klaxon. I think the better way will be to continue the use of the double wires in the steering column. With this arrangement we dispose of the whole of the switch problems for both of our chassis. It is a superior arrangement to what they are using in the States inasmuch as they cannot run their engine without charging. They cannot prove whether either ignition is in good working condition because their switch only provides for switching on both ignitions at once, and the charging is not dealt with by switches, but only by the automatic accumulator switch. Personally I do not approve of the American electrical installation (we had to agree to avoid stopping production) and we have not yet had a satisfactory Westinghouse equipment for Derby to pass as being suitable and reliable. R.{Sir Henry Royce} | ||