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).
The EAC.10 valve gear, comparing rocker shaft dimensions and estimating shaft deflection under load.
| Identifier | ExFiles\Box 17\6\ Scan025 | |
| Date | 27th February 1928 | |
| X. 7060 R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} c. to BJ. Hs.{Lord Ernest Hives - Chair} E2/M27.2.28 EAC.10 VALVE GEAR. = Pro rata with the 20 HP., the .750 dia. valve rocker shaft on EAC.10 is on the small side, since the former has a dia. of .625". There are two features however which compensate for this to some extent. The bore in each case is the same, and the dia. of the vertical holes for the fixing studs is the same, this latter providing a much improved section where the shaft is fixed. It is not easy to arrive at an exact value for the deflection of the shaft, owing to the complications involved in the system of mounting, and the manner in which the load is applied. We estimate however that with the valves on the point of jumping, and assuming the load to be suddenly applied, the deflection is in the neighbourhood of .001". The stress of course is quite low. E.{Mr Elliott - Chief Engineer} | ||