GB1072760A - A method and device for supplying a combustible mixture to an internal combustion engine - Google Patents

Abstract

1,072,760. Spray carburetters. M. A. ARPAIA. Sept. 30, 1964, No. 39799/64. Heading F1B. Fuel supplied under pressure to chamber 82, Fig. 4, is sprayed into a primary air stream in pipe 89, the rich mixture flowing to a tube 34 through slots in which it flows into a secondary air stream, the fuel supply being controlled in accordance with the flow of secondary air. The tube 34 forms part of an eccentrically pivoted vane 33 which moves in accordance with the secondary air flow, the spindle 100 of the valve being connected through a spring 105 to a shaft M' which rotates a main fuel valve M controlling a main fuel orifice M". An idling jet I" is controlled by valve I on a shaft I' controlled manually from the accelerator linkage 22, Fig. 2, and by a piston 40 subject to manifold suction, and an accelerating jet A" is controlled by a valve A operated from the accelerator linkage 22. The piston 40 rotates a shaft 49 having an arm 75 cooperating with an arm 78 on the idling shaft I'. The accelerator linkage 22 operates the air throttle valve 28 through a disc 31 on its shaft 30, which disc is connected by link 65 to a disc 60 freely rotatable on shaft 49 and carrying an arm 62 which can over-ride the arm 75. A second link 122 from disc 31 operates the accelerating valve shaft A'. Exhaust gas admitted at 20 and controlled by a valve 52 on shaft 49 flows through a passage 20a to heat the carburetter body and vaporize the fuel in the passage 89, the exhaust gas flowing through passage 20c into the combustible mixture passage. The exhaust gas also heats a copper tube 21 in the mixture passage downstream of the valve 33. The fuel is supplied at constant pressure by a pump P Fig. 1 (not shown) from a tank 11 which is vented through pipe 17 to a passage 18 leading crankcase gases into the mixture passage. Starting and Idling. At starting the accelerator pedal is depressed to open valve 28 wide, Fig. 8 (not shown) and linkage 122 moves valve A to open accelerator jet A" whilst linkage 65 moves arm 62 to contact arm 78 to open idling valve I, the main jet M" being closed. A bi-metallic strip 56 is curved when the engine is cold to form a fast idle stop co-operating with arm 54 on shaft 49 to hold the throttle valve in the fast idle position in which the accelerating jet is closed but the exhaust passage 20b is fully open. As the engine warms up, strip 56 allows throttle 28 to close completely, valve 52 on shaft 49 then closing the exhaust orifice 20b and the idle jet I" being controlled by a port 126 in the valve I, the piston 40 being pulled to the right by the suction to move arm 75 from beneath arm 78. Normal running. As the accelerator is depressed the valve 33 opens with increased airflow to rotate the valve M and open the normal running jet M". Piston 40 moves to the left with increasing intake manifold pressure, whereby valve 52 reopens exhaust orifice 20b. Under cruising conditions linkage 108, 111, moves valve shaft M' relative to the actuating member 100 to reduce the fuel supply slightly. Deceleration. The high intake manifold suction upon deceleration moves piston 40 to the right sufficiently to close idling valve I and cut off the fuel supply, valves A and M being already closed upon closing of the throttle valve.