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).
Leaflet describing the scientific principle, construction, and fitting of the Giusti Gauzeless Filter and Separator.
| Identifier | ExFiles\Box 44\1\ Scan017 | |
| Date | 3rd December 1920 guessed | |
| In the Old Days. In pre-war days, even when petrol was comparatively clean, a petrol filter was a necessary fitting, but at the present time, when motor spirit is full of impurities, and, in the case of benzole, it is sometimes accompanied by a percentage of water, a reliable filter is as essential as a part of the engine. The old-fashioned filter was, at best, but a crude affair, relying upon, more or less efficient, wire gauze, that might, or might not, stop the progress of grit, or other foreign matter, but which in respect to water was quite useless. Motor spirit, being a liquid, naturally flows direct to the carburettor; in the event of it containing any water there is nothing to stop the latter, gauze being quite useless in this respect, hence the frequent stoppages of an engine in the past, for which a guiltless carburettor was often blamed. A NEW SCIENTIFIC PRINCIPLE. The Giusti Gauzeless Filter and Separator is a scientific invention, as far in advance of the old method, as the motor is ahead of the horse, and contains no gauze which, sooner or later, became partially, or completely, choked up. Should cleaning, however, be necessary, the actual filtering member, consisting only of two parts, can be easily removed in a few seconds. The illustration on the front page of this leaflet, shows how very neat in appearance is the new Filter described herewith. The sectional drawing shown on this page, explains very clearly the principle upon which it operates. The petrol, or other spirit, enters the filter at position marked A, passes through B, a tube which has a sharp edged open end, this inner tube is contained in another chamber, so that the motor spirit, after leaving the tube B, enters the chamber marked C, which has no direct through passage, in consequence of which the spirit is diverted to the exterior of the inner tube (B), so that it traverses to the end of the chamber (C), which again has a sharp edge, to catch any lint, or soft matter, which might perchance have found its way into the petrol or benzole. The fuel is now in the outer filtration chamber. Should there be any water or other foreign matter, this being heavier than the spirit, it naturally sinks into the sump marked E, while the spirit, being lighter, rises to the upper part of the chamber F, and from there makes its way by means of five, or eight (according to the h.p. of the engine) holes drilled at inclined angles connecting the outer filtration chamber with the exit marked D, leading to the carburettor. Any water, or foreign matter, which naturally takes the lower, and easier, course, goes into the chamber E, where it sinks into the sump at the bottom, and can be drawn off from time to time by a tap, or screw plug fitted at the base. The sharp edges of the tube B and the inner chamber C, break up all globules of heavy liquid. Should any, however, be carried over the sharp edged tube, and chamber, and arrive at the outer chamber F, these will at once settle at the bottom, owing to the very much larger cross-sectional area above the tube and chamber (A and B), as compared with that of the out-flow passages leading to D.{John DeLooze - Company Secretary} The motor spirit flows at an extremely slow rate, which also causes such particles to settle instead of passing out into the petrol pipe leading to the carburettor. CONSTRUCTION AND MATERIAL. Having described the simple, and ingenious, principle upon which the Separator works, it is necessary to mention that the efficiency of same depends upon the material of which it is constructed, and the accuracy of the workmanship, to ensure that the Filter, as a whole, shall be absolutely gastight. The main filtration chamber is beautifully made in aluminium, while all other parts are of solid brass, thus being rust proof. FITTING. Many valuable motor accessories have the great disadvantage of being either difficult to fit, or suitable only for certain types, or makes, of engine; the Giusti Filter is unique in this respect, it is | ||