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 valve rockers and cams for a new 750 HP engine, with an accompanying sketch.
| Identifier | ExFiles\Box 43\3\ Scan098 | |
| Date | 21th December 1926 | |
| RG.{Mr Rowledge} To E.{Mr Elliott - Chief Engineer} Hs.{Lord Ernest Hives - Chair} ) FROM R.{Sir Henry Royce} +4003 R1/M21.12.26. c. to BJ. Wor.{Arthur Wormald - General Works Manager} F.10. XXXXXX VALVE ROCKERS. X.4003 X.3866 X.4011 X.3822 It may prove best to still have the exhaust with rollers because of the extra stress of opening the valve against the exhaust pressure, plus acceleration. The breakage seems quite straightforward - i.e. not torsion so can easily be catered for, especially if a little more room is taken sideways. But let us have both tested. I have also suggested single separate rockers for each inlet, with sepra separate cams. I send herewith a sketch of a possible improved arrangement for new 750 HP. i.e. equally spaced and twisted round, just enough to make rockers and cams clear. I am not saying it it better, but it is worth a trial - rough drawing. [Diagram of a circular valve arrangement with four valve stems] Rocker A.{Mr Adams} Rocker B. Two types of rocker - an A.{Mr Adams} and B. for exhaust. " " " " for inlet. Central cams would need to be slightly different to outside. The design of this larger engine is so very urgent that it seems to me unless we can at once see some advantage in departing from the vertical valves, we ought to go on with the RR. F.10. type of cyl. block. Also it would not be a tremendous expense to alter the block (cyl.) later, should we find a better scheme when we have more time. R.{Sir Henry Royce} | ||