| 摘要 |
458,698. Spray carburetters. MOORE INVENTIONS CORPORATION, Worcester, Massachusetts, U.S.A. July 27, 1935, No. 21410. Convention date, July 27, 1934. [Class 7 (iii)] Fuel is admitted from a float chamber to a fuel passage, opening into an intake passage on the engine side of a throttle valve, through a variable orifice disposed below the normal fuel level in the chamber, the area of the orifice being determined by the position of the throttle, and air bleeds into the fuel passage to modify the pressure differential acting on the orifice. The area of the fuel orifice varies directly with the throttle opening during a portion of the extent of opening of the latter and inversely during a later portion. Rigid with an air throttle valve 18 is a cam 16 shaped as shown in Fig. 2 to depress a fuel metering rod 12 during initial opening movement of the valve, then to allow a spring 14 to raise the rod when the throttle is at a point corresponding to transition from normal to full load running and finally to depress the rod again as the throttle becomes fully open. The end of the rod is bevelled at 20 to provide a single sector-shaped opening for the fuel which receives a primary charge of air past a valve 26 urged to close by a spring 33 but opened by suction applied through a passage 30 to the back of the valve. The rich mixture traverses a passage 24 to an outlet 34 in the throat of a Venturi 35. The maximum flow of fuel is controlled by a submerged nozzle 38 smaller than the passage 10 controlled by the rod 12. As the throttle opens, the spring 33 closes the valve 26 and a small quantity of air is then provided by a calibrated orifice 36 unless a reduction in the suction has allowed fuel to accumulate in a well portion 24u of the passage 24, the fuel then requiring to be lifted only the distance from the level 44 to the shoulder 24f of the passage 24. A throttle-operated pump 50 supplies fuel for acceleration through a tube 62 provided with air inlets 64 to prevent fuel from being drawn into an acceleration nozzle 58 by suction alone. The nozzle 58 sprays fuel on to the outlet pipe 34. |
