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).
Design of contact makers and exhaust valves for battery ignition systems, including cam timing diagrams.
| Identifier | ExFiles\Box 61b\1\ scan0014 | |
| Date | 31th January 1927 | |
| X.4041 To E EFC. )FROM R.{Sir Henry Royce} Hs.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} ) (At Le CanadelHenry Royce's French residence). R5/M2B.1.27. DESPATCHED FROM WW. 31.1.27. c. to BJ. Wor.{Arthur Wormald - General Works Manager} BATTERY IGNITION. EXHAUST VALVES. X.4041. X.4652. X.2894. CONTACT MAKER. diagram 30° - If this is off-set 30° does it not incline the [Diagram of sine curves] Normal sine cure Distorted ditto. [Diagram Annotations]: SLOW MAKE INCLINED 30° LIFT LOWER FAST BREAK EQUAL MAKE & BREAK You will remember that I suggested quicker break, slow make, might be an advantage, but intended that the cam should be so designed. E.{Mr Elliott - Chief Engineer} finds Delco and Bosch both off-set for the same end. I have also suggested something the same about the valves - exhaust - to save burning and yet avoid noise. We must prevent the contact maker and the valve being thrown higher than the cam. You will see elsewhere that I have pointed out that an overthrow damping scrubbing spring could be fitted, thus - (believe we saw similar one in Watford magneto contact makers) [Diagram of a contact maker mechanism] | ||