Patent GB-717836-A (GB)
Title: Improvements in or relating to carburettors for internal combustion engines
IPC: F02M7/22
Filed: 1951-07-23
Abstract: 717,836. Spray carburetters. LERP, E., and NEUERBURG, G., [trading as VERGASERBAU HAMBURG G. NEUERBURG & CO.]. July 23, 1951 [Jan. 19, 1951], No. 17348/51. Class 7(3) A main air valve 38, Fig. 8, is slidably mounted for axial movement in a cylindrical valve guide 37 having a fuel inlet port 36 in the wall thereof, the valve also having an axial fuel supply passage 50 through which fuel can pass for mixing with the air, a radial port 49 in the valve communicates with the passage and is adapted to be partly or wholly cut off from the fuel inlet port, and means is provided for effecting axial movement of the valve whereby as the valve is lifted from its seat to increase the air supply the fuel supply is correspondingly increased and vice versa. Fig. 8 shows the parts of the carburetter in the idling position in which fuel which enters at 29 can pass through the passage 50 to a channel 53 of a nozzle piston 42. The axial movement of the valve 38 is effected by means of a cable 65, Figs. 3 and 7, and a lever 62 with an attached finger 57. If the valve 38 is lowered, Fig. 8, the fuel supply is cut off since the passage 50 moves out of communication with the port 36, and if the valve is raised the power is increased, the full load position being reached when the valve is fully raised. During this raising movement the end 58 of the finger 57 moves away from a recess 51 and permits the piston 42 to move under the action of a spring 43 relatively to the valve 38 so as to open an annular passage for fuel between the head 54 and a conical recess in the end of the valve 38. A further control is provided by means of a cable 69, Fig. 7, by means of which the valve 38 may be rotated to vary the fuel flow by shifting the passage 50 relatively to the port 36. During idling, air passes through radial openings 46 down inclined grooves 55 and through radial channels 56 into the fuel channel 53. At higher powers a small quantity of air passes through the openings 46. The valve 38 is turned by a pin, not shown, which is carried by a lever 70 and co-operates with a slot 47. The air supply enters through spaces 27. A spring bow 3, Fig. 1, secures a cover 2 and its ends 4, 5 hold an air filter 15. Numerous modifications of fuel control incorporated in the valve 38 and its guide 37 are described. The fuel may be supplied through a rotatable member having an eccentric outlet orifice, rotation of the member varying the fuel flow by varying the position of the port. Two grooves may be provided in the member 38, one for idling, and each may include a control device. The cross section of the groove can be altered by an adjustable plate. A suction operated valve may be provided in the fuel supply passage. In another arrangement a rotatable member with an eccentric fuel bore may be controlled by capsules acted on respectively by suction and fuel pressures. In Fig. 25 the shape of a fuel supply groove 112 may be varied by means of adjustment screws 116, 117. In Fig. 26 the fuel flow is varied by movement of a valve 38, a port 119 co-operating with a groove 123 in the rod 122. The rod may be axially displaceable.