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).
Design notes on a blower, covering oil accumulation, fuel-oil mixing, and carburetor modifications.
| Identifier | ExFiles\Box 140\1\ scan0016 | |
| Date | 24th August 1932 | |
| (2) E.6/HP. 24.8.32. disposing the masses of the blades relative to the coupling. In connection with the design of the blower Mr. Eyston mentioned that it was desirable to limit the amount of oil which could accumulate in the Oldham coupling chamber as after a long period of idling this oil was liable to foul the plugs when opening up. They are drilling holes in the partition between the coupling and the rotor to overcome this trouble. In our latest design of Bensport blower following the WW. conference we have restored the metering oil pump to the nose of the blower to avoid driving it from the engine, to provide for the starting handle drive we show an intermediate jawed piece which also acts as a valve to seal the nose of the blower when not in use. We find that Messrs. Powerplus have a scheme similar in principle for front driven blowers and have since sent us a print of their standard fitting. With regard to the percentage of oil which all types of blowers require to be mixed with the fuel it is important that some provision be made for properly mixing the two liquids when replenishing the fuel tank. If the oil is just poured into the tank it is liable to stay at the bottom unmixed. The scheme recommended by Mr. Eyston is to use an oil container with a gauze covered mixing port which fits into the main fuel tank filler, and holds just the right amount of oil for a full tank and thereby acts as a gauge. The movement of the fuel due to the motion of the car washes the oil out through the gauze covered opening and assures thorough mixing and the necessity for withdrawing the oil container for the purpose of filling the tank serves to avoid the oil supply being forgotten. With regard to the S.U. carburetter we are arranging to use in conjunction with the blower, Mr. Eyston tells us that with a heavy boost it is necessary to add extra weight to the air valve to stop vibration. Presumably this alters the period of the valve. The S.U. carburetter should also be fitted with the top feed type of floatchamber to avoid starvation of fuel. With regard to the durability test we are about to run on a No.10. blower it was agreed that we should run the blower on a mixture of fuel and air, and that a cooling blast | ||