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).
Discussion of various schemes for automatic throttle stop and mixture control systems.
| Identifier | ExFiles\Box 133\4\ scan0020 | |
| Date | 16th June 1934 guessed | |
| - 2 - a limited number of drivers and are being washed out by improvements in the transmission mechanism. We have a number of schemes for dealing with the throttle stop control which we believe are somewhat novel, one is to use an eccentric against which the throttle stop lever contacts, the rotational position of the eccentric being controlled by a coil of bi-metal strip. Another is to use a compound tube thermostat screwed into the cylinder head and directly operating the throttle stop. Another is to use a bellows thermostat operating the throttle stop through a thread or eccentric. A further scheme is to utilise the mixture control scheme proposed by E/PSN which has a master bellows and a small working bellows by adding another working unit controlling the throttle stop. We are putting all of these proposals into a sort of pantechnicon specification to see if we can protect them, but we may find on investigation that the ground has already been covered by Stromberg. On the other hand we may find this line of development to be untouched as Stromberg owing to the non expanding type of carburetter they employ, have had to use a latch scheme for the slow and fast idle which operates when the accelerator pedal is depressed and the thermostat in this case also controls the choke for starting. We in our case do not require a choke with the S.U. carburetter, and our complete proposal is a combined automatic mixture control and idling control which includes the S.U. scheme for connecting up the induction pipe vacuum for weakening off when the throttle is opened. Thus the following functions will be provided by automatic means:- (1) Rich mixture for starting fromcold. (2) Fast idling speed for cold engine. (3) Weakening off of mixture if throttle opened with cold engine. (4) Weakening off of mixture to normal as engine warms up. (5) Slow idling speed for warm engine. (6) Normal mixture for starting warm engine. Having got rid of the throttle control | ||