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).
Continuation of a report comparing governor control sensitivity and calculations for spring requirements.
| Identifier | WestWitteringFiles\M\2Jan1925-March1925\ Scan14 | |
| Date | 1st January 1925 guessed | |
| -4- which in the extreme case only increases the throttle opening by 1/240 of the total range, a hardly appreciable amount. Now upon another occasion the governor is set to give a speed of 30 m.p.h. when ascending a gradient so that the cam is on the rapid portion of its movement. A variation in gradient causes a momentary drop of 100 r.p.m. whereupon the cam is rotated through the same amount, 12 1/2°, but the throttle opens through 1/8 of the total movement. The EAC. governor control is therefore 30 times as sensitive in the latter case as the former, while the 40/50 governor would open the throttle through 1/20 of its total range in each of the cases mentioned. To expect to get the same consistency of operation out of each governor arrangement is therefore unreasonable. -------------- Spring required to make throttle governor more sensitive. Governor and actuating spring in equilibrium. Then pull from spring = x lbs. " " governor = x lbs. Suppose engine r.p.m. falls n. R.P.M. and in consequence that the pull of the governor falls y.lbs. Now the governor spring rating = p lbs/1". . . movement of the end of this spring when load is decreased by y.lbs. = y/p Now y/p is required to be a maximum. Therefore p is required to be a minimum. contd :- | ||