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).
Technical letter discussing different models of Coils and Distributors for various engine applications.
| Identifier | ExFiles\Box 52\3\ Scan278 | |
| Date | 15th November 1917 | |
| Continuation No. 2. Messrs. Rolls-Royce Ltd. 15th November, 1917. following:- Our Model 171A Coil [handwritten insert: which] works in conjunction with our Model 108 Distributor or Model 209 Distributor, and this Distributor is fitted with a cam having a relatively sharp peak allowing for a comparatively long time of contact and short time of break. [handwritten note: { Six cylinder set for airship engines.] We have also submitted to you for Mr. Day's inspection a newer type of Distributor and Coil, the Distributor being fitted with a more economical [handwritten insert: Cam] Coil from a point of view of current consumption, the cam being designed to give a larger time of break and a shorter time of make, and the Coil, which we are supplying with this is known as Model 284A, is purposely designed with a lower self-induction in order that the current may build up more quickly to compensate for the short time in which it is allowed to build up current. For exceptionally high speed engines, that is to say, for 6-Cyl. engines running up to 4,000 r.p.m., which, of course, is higher than aircraft engines run, we should supply our type known as our Model 286A, which has a still lower self-induction. The question of [handwritten insert: current] running consumption also affects the type of Coil which should be used, inasmuch as the storage | ||