GB1233820A - - Google Patents

Abstract

1,233,820. Spray carburetters. FORD MOTOR CO. Ltd. Jan.1 1970 [Jan.6, 1969], No. 61687/69. Heading F1B. A carburetter idle air/fuel system includes an air/fuel emulsion passage 26, Fig.1A, having an air inlet end connected to the main induction passage 12, Fig. 1, upstream of a throttle 20 and a restricted fuel/air outlet end connected to the induction passage downstream of the throttle, the inlet end containing a fuel jet 44 positioned in the air-flow so that fuel is discharged along the axis of the emulsion passage which is of a diameter large enough to eliminate wetting of the emulsion passage walls thereby minimizing fluctuations in the fuel flow rate. A transfer passage 54 is connected to the emulsion passage through a restriction 58 to minimize flow disturbances when the throttle 20 is in the idling position. In a modification the air inlet flow is adjusted by a metering needle (60), Fig. 2 (not shown) and the transfer port (54<SP>1</SP>) is connected to the inlet end of the emulsion passage through an orifice controlled by a metering needle (62), the emulsion passage being connected to the induction passage at its outlet by a narrow passage (36<SP>1</SP>). In a further modification the outlet passage (36<SP>1</SP>) may have two different diameters. In another embodiment a guide wire 64, Fig.3, is mounted axially in the emulsion passage. In operation the wire core increases the stability of the fuel jet which finally breaks away from the wire at the outlet passage 34<SP>11</SP> to form a finely atomized fuel spray. The flow area of the outlet passage may be variable. An additional adjustable air by-pass passage may be connected to the air passage of the idle system.