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).
Letter to S.U. Carburetter Co. Ltd. questioning the design of contact points in petrol pumps.
| Identifier | ExFiles\Box 163\1\ img023 | |
| Date | 2nd July 1934 | |
| 86007 Hs{Lord Ernest Hives - Chair}/Wst.5/MA. 2nd July, 1934. The S.U.Carburetter Co.Ltd., East Works, Bordesley Green Road, Adderley Park, Birmingham, 8. For the attention of Mr.Skinner. Dear Sir, We should like to know the reason for the use of Tungsten as a contact point material on the S.U. Petrol Pumps. Our experience is that with Tungsten the contact points must be worked with a minimum current density to avoid oxidization and we find that the contact points on the petrol pumps at the works do oxidise showing that the current at break is on the high side. We would suggest the use of other material than Tungsten as the result of our experience in other directions. We should also be interested to know why you use two points instead of one. Although the points are in parallel it is extremely difficult to maintain them in such a conditions that they equally share the current, what so often happens is that one point becomes slightly oxidised and the whole of the current is therefore transferred to the other point causing severe oxidization of that poin. Yours faithfully, FOR ROLLS-ROYCE LIMITED. | ||