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).
Provisional patent for a new carburetter design with a diagram.
| Identifier | WestWitteringFiles\R\October1927-December1927\ Scan114 | |
| Date | 30th November 1927 | |
| BY.{R.W. Bailey - Chief Engineer} FROM E.{Mr Elliott - Chief Engineer} C. to HS.{Lord Ernest Hives - Chair} BY/NW.{N. Walker - Patents} ORIGINAL E1/M30.11.27. PROVISIONAL PATENTS - CARBURETTERS. X8080 X3933 X728 Referring to BY9/G221127., the specification No.222901. does not cover the suggested improvement in R1/M291027. The latter is a new arrangement of the expanding type of carburetter, the choke tube being fixed, and a tulip shaped restrictor being drawn downwards or outwards by automatic means. In this form of carburetter it is the choke tube that is moved generally and this has a number of objections. The carburetter cannot have an unobstructed vertical gas way. The sliding bearing of the choke is of large dia. and has appreciable friction. It creates leakage and gets jammed by drawing in dust. These difficulties and disadvantages either disappear or are considerably minimised when the choke remains fixed and the restrictor is moved as in sketch. It is best used in conjunction with an annular petrol feed through the choke. A dashpot is provided attached directly to the tulip to damp out the effect of rebounding pressure waves from the induction pipe. The air valve could be made to operate directly from a position immediately beneath the restrictor. Regarding your 2nd. para. this idea is to make an expanding carburetter, the opening of which is controlled by a centrifugal governor driven by the engine and is hence a function of the speed. With such a carburetter we could arrange for any depression desired at any speed. The depression in the carburetter could be lower at maximum speed than when pulling hard slowly if required. In our particular case it happens that we have a means ready to hand in the governor controlled oil relay for such a purpose. It should be understood that this has nothing to do with the carburetter throttle valve which is operated as usual from the accelerator pedal or the throttle governor. The speed governor is intended to perform the work at present carried out by the carburetter air valve and spring on our present carburetter, but is independent of induction pipe pressure. It could be coupled to the tulip restrictor suggested in the carburetter described in the beginning of this memo. [Diagram labels] AIR PISTON OIL DASH POT E | ||