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).
Inefficiency and proposing modifications to a governor springing mechanism, including a diagram.
| Identifier | ExFiles\Box 37\1\ scan 302 | |
| Date | 4th May 1926 | |
| Contd. -2- RL/M4.5.26. coming to zero with a governor starting to open at 250 revs. equalling 500 crankshaft speed. We think there should be an initial advance of anything up to crankshaft 30 to be sure that the governor is not losing part of its stroke with no advance of the ignition. This we term 'relay lag'. There is no excuse for relay lag and there is only excuse for governor lag due to the unavoidable friction in the governor mechanism. The inefficiency I complain about appears on some further inspection of 7-EX, to be due to over rigid governor springs. Perhaps also the governor does not start soon enough, probably 400 governor revs. instead of 250, and then the advance is only about half the rate we desire because the governor springs not only have 8° initial set (instead of no set in view of gravity effect of inner piston, valve) but the spring should be of wire about half as rigid. SUGGESTED MODIFICATION TO GOVERNOR SPRINGING. Improved scheme; same spring, half torque, half angle, half stress, same gauge of wire. Initial set unnecessary. gravity acts for 250 revs. At 750 revs. 80% of gov. opening should have taken place. Small free shaft Each spring equalises but has no only moves through movement. 35° instead of 70° With our present scheme of springing the governor seems unsuitable in view of the quantities, and considering the difficulties, the scheme here given which is really simpler, is the better by far because it permits a larger gauge of wire. Do not reduce governor weight; this would be very unwise. Contd. | ||