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).
Proposal for a new ignition coil design, including details on its casing and electrical specifications.
| Identifier | ExFiles\Box 164\5\ img374 | |
| Date | 29th June 1938 | |
| c. Rm.{William Robotham - Chief Engineer} 6017 DA.{Bernard Day - Chassis Design}4/G.29.6.38. IGNITION COILS. Herewith D.CD.757 Ignition Coil proposal. We have taken the opportunity to have a longer and larger diameter case of sheet metal construction. Regarding the electrical particulars, the dimensions of the core have been chosen for magnetic circuit only, and have not been made long to suit the general construction, a coarser secondary winding has been chosen, with thicker layer insulation. This is expected to give an improved performance for slow running rather than a high K.V. output. The latest experimental primary has been repeated, but for a subsequent test a winding of more turns and similar resistance has been chosen. This and filling the case with bitumen filling should help to reduce temperatures. DA.{Bernard Day - Chassis Design} | ||