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 from S.U. Carburetter Co. Ltd. clarifying modifications to an armature, spindle, and high-pressure pot.
| Identifier | ExFiles\Box 149\6\ scan0051 | |
| Date | 30th September 1937 guessed | |
| THE S.U. CARBURETTER CO. LTD. CONTINUATION No. 2. Messrs. Rolls-Royce Limited. As regards the truth of the armature and spindle, we quite agree that this should be true. What we meant to infer in our previous letter was not that we considered it unnecessary but nothing is perfect, and we thought possibly you would like to put some limit on this. As regards the alteration to the pot, the explanation of this is that the high pressure pot was originally experimented with a year or two back. When you asked for a high pressure pump the old experimental job was raked out and used as a basis. Since the time when we first started experimenting on this, we have made slight modifications to the standard pot. Furthermore the high pressure pot was originally made with 3/16" thick flange. We cannot remember at the moment why this was done, probably because it was simply a heavier job. Since it is made in steel however, we consider this is unnecessary and it means different studs. It therefore seemed to us when you asked for drawings, it would be as well to bring everything up to date including the alteration in the mouth of the pot. The reason for this alteration was that as a result of experience we found that the difference between the amount the diaphragm was bent in and the difference it was bent out was excessive and therefore we altered the depth of the first step in the mouth of the pot to reduce this. This has been current for a long time now. It does not affect the pump magnetically in any way as the core is located from the second step and the armature is set from the core. In other words, this alteration was merely made to improve conditions for the diaphragm without altering anything else. Will you kindly let us know therefore which set of dimensions you would like us to work to. Yours faithfully, For THE S.U. CARBURETTER CO. LTD. P Leslie Kent | ||