Technical comparison with formulas for the respective behavior of 40/50 HP and EAC governors.
| Identifier | WestWitteringFiles\M\2Jan1925-March1925\ Scan12 | |
| Date | 1st January 1925 guessed | |
| -2- GENERAL. RESPECTIVE BEHAVIOUR OF 40/50 & EAC. GOVERNORS. Let engine r.p.m. be n. R.P.M. " pull from governor be X lbs. " " " spring x lbs. Rating of " " p lbs/1". Let engine revs. fall by r. {Sir Henry Royce} R.P.M. Then new pull of the governor = x((n - r)^2 / n^2) lbs. Consequent movement of controlling spring end will be - x((n - r)^2 / n^2) ins. Now on 40/50 HP. 1" movement at the end of the controlling spring gives the complete range of throttle opening. . Fraction of total opening by which the throttle opening is increased for a drop of n. R.P.M. [ x [ (n - r)^2 / n^2 ] ] / p On the EAC. .4" movement at the end of the controlling spring gives 45° movement to the camshaft of throttle slow opening cam. . Increase in camshaft degrees of rotation for a drop of n. R.P.M. [ x [ (n - r)^2 / n^2 ] / p ] X [ 45° / .4" ] but the value of 1° camshaft rotation as regards throttle opening varies from 1_o to 1' Therefore in the case of the EAC. there is no constant fraction by which the throttle is opened for a drop of n. R.P.M. contd :- | ||
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).