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).
Proposed alterations to the 'GOSHAWK II' carburettor, including the addition of a silencer and changes to the controls.
| Identifier | ExFiles\Box 180\M1\1\ img079 | |
| Date | 11th October 1921 | |
| To HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} Copy to C.J. " " MOR. " " BY.{R.W. Bailey - Chief Engineer} " " DA.{Bernard Day - Chassis Design} [STAMP: RECEIVED OCT 13 F.C.] [STAMP: ORIGINAL] R5/G11/10/21. RE "GOSHAWK II" CARBURETTOR. X4228 We are altering the form of the carburettor casting and the upper part of the mixing chamber where the air enters so as to adapt it for a silencer which will cover this opening, and also the opening below the throats. The air will enter this silencer at a slow rate and pass through concentric tubes so as to prevent the noise of the high speed air in the induction pipe being communicated with the external air. You will see therefore that many of the castings of the carburettor will require definite alteration on account of this silencer. We are proposing also to alter the control so as to work the main butterfly valve only for all running purposes. This will avoid the noise from the air rushing into the small jet. We propose altering the small jet to one with a moving throat, so that it will tend to weaken the mixture the greater the suction of the engine. This will be somewhat in accordance with the starter fitting you sent us. We are, however, altering it so as to cut off the air entirely when the suction gets to the minimum. This jet will be hand regulated by lifting the bonnet, and can be set very strong so as to give cold starting, and can be easily diluted by the main throttle. We shall therefore finish up with a somewhat complicated carburettor, but more simple controls; a mixture control on the dash for the ordinary carburettor, and a cock control on the dash for the starter. This should give a scheme about which there is no doubt of it acting satisfactorily, and therefore ready for immediate production. In the meantime, hold up the production of the present castings pending this alteration, as it will affect both the patterns and the tools. We propose designing another carburettor altogether with (Contd.) | ||