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).
Detailed explanation of the function and benefits of the G. U. C. Patent Sprayer Nozzle in a carburettor.
| Identifier | ExFiles\Box 122\4\ scan0106 | |
| Date | 17th April 1936 guessed | |
| 6 is unconditionally guaranteed to function perfectly and outlive several cars. THE SPRAYER NOZZLE (Fig. 2 “E”) In order to produce a perfect combustion mixture, the petrol must be broken up into the finest possible spray to form a homogeneous mixture with the air admitted by the choke tube. There is as much difference between the G.{Mr Griffiths - Chief Accountant / Mr Gnapp} U. C. Patent Sprayer Nozzle and any other device for the same purpose (Fig. I.H.) as there is between a syringe and a garden rose sprayer. The Sprayer Nozzle (Fig. 2 “E”) forms a cap for the main petrol outlet. It is placed centrally in the choke tube, and is built up of an inner tube (F) and an outer tube (G). The inner tube is the passage for the petrol from the main and balancing jets, and the outer tube conveys air to the sprayer nozzle. The cap or nozzle (E), the top of which is machined at an obtuse angle receives the petrol tube (F) in its centre, and has three or more small and equally spaced holes (K) drilled at an acute angle just above the central petrol feed. These holes communicate with the outer or air tube. When the throttle is opened and a depression is created in the choke 7 tube, air at high velocity is injected through these small holes into the stream of petrol issuing from the central hole, breaking up this stream into a fine mist, which when mixed with the main air stream through the choke tube, forms a perfectly homogeneous gas. In the case of the ordinary carburettor one can see jets of liquid petrol spurting out into the choke tube. In the G.{Mr Griffiths - Chief Accountant / Mr Gnapp} U. C. the mist of petrol is so fine that it is almost invisible. The G.{Mr Griffiths - Chief Accountant / Mr Gnapp} U. C. therefore delivers to the combustion chambers of the engine, at all speeds, not only a perfectly emulsified vapour, but also a mixture of air and petrol in scientifically correct proportions never heretofore obtainable. The result is absolutely even combustion throughout the engine cylinders. An ordinary carburettor delivering a partly liquid mixture sets up what is called stratification which arranges itself concentrically around the piston head. In these conditions the correct mixture may only form itself in a ring about half-way between the centre and the cylinder walls. The outside | ||