Changes to the insulation of ignition coils for 20-HP & 40/50 HP chassis.
| Identifier | ExFiles\Box 69\1\ scan0283 | |
| Date | 31th December 1929 | |
| RHC. {R. H. Coverley - Production Engineer} EFC. {E. Fowler Clarke - Electrical Engineer} X 8710 BY {R.W. Bailey - Chief Engineer} /RD1/DM. {D. Munro} 31.12.29. Ignition Coils. 20-HP. & 40/50 HP. Chassis. Would you please arrange to let EFC. {E. Fowler Clarke - Electrical Engineer} have 2 Ignition Coils which are standard in all respects, except that the secondary insulation consists of 2 turns per layer instead of 3 turns per layer of waxed or varnished paper. The first 3 layers of secondary will be insulated with 4 turns of insulating material instead of oiled silk as at present. This new coil should be marked with the piece number D.72450. The object of this is that we get a more solid winding together with an economy in wire and insulating paper, in fact the less paper we use the less amount of air is trapped therein. Will EFC. {E. Fowler Clarke - Electrical Engineer} please test these 2 coils, one of which should be wound with varnished paper and one with waxed paper, and as soon as possible, as we propose to adopt this on production forthwith. BY {R.W. Bailey - Chief Engineer} /RD. | ||
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).