Patent GB-110807-A (GB)
Title: Improvements in or relating to Carburettors for Internal Combustion Engines.
Inventor: DICKER STANLEY GORDON SINCLAIR
IPC: F02M19/00
Filed: 1916-11-10
Abstract: 110,807. Dicker, S. G. S. (Stromberg Motor Devices Co.). Nov. 10, 1916. Spray carburettors.-The main fuel supply is controlled automatically by the mixture throttle in such a way as to give full flow with both high and low suctions and a restricted flow with intermediate suctions. A carburetting-chamber 9 placed between the main air inlet 11 and the mixture outlet 12 contains two Venturi tubes 13, 52, the lower of which extends through the narrow part of the upper one and contains a radial series of fuel inlets 55 communicating by a p'assage 56 with a well 23, to which fuel from the float chamber 19 is admitted through a valve 27, Fig. 6, operated in conjunction with the throttle 16. A cam 57 on the throttle-shaft 17, Fig. 1, engages a three-armed lever, the arm 61 of which operates the valve 27. Nuts 28, 30 on the valve-stem regulate the maximum and minimum opening of the valve. The cam has two projecting portions 58, 58<a> which operate when the throttle is closed or wide open, and a depression 59 between them, corresponding to a partial opening of the throttle. Consequently when the engine is running at very low or at high speeds, the valve 27 is open giving an abundant supply of fuel, but for intermediate running, the supply is restricted. A valve 14, Fig 2, controlling the main air inlet and operated from the dash-board, carries a cam 65, Fig. 1, which engages an arm 62 of the lever and serves to open the valve 27 when the air inlet is obstructed, independently of the throttle. When the throttle is wholly or almost closed, fuel is sucked up a pipe 38 to a discharge opening 43 placed close to the surface of the throttle, and air is drawn through an adjustable opening 45 to mix with the fuel. This supply ceases when the throttle is open, and the holes 55 comes into operation. Air is also sucked through the holes 55 from an opening 41 placed just below the normal liquid level X - - X; this opening communicates with an annular space around the pipe 38, opening to the atmosphere through an annular groove 50 and orifice 51. During acceleration, when section is increased, additional fuel is supplied through an opening 73, Fig. 2, placed just above the holes 55, from a well 24, Fig. 6, which contains a tube 68 with perforations 74 at different levels. The opening 73 communicates with the upper end of the tube. Air enters the space around the tube through openings 75 and during steady running is sucked though the uppermost perforations, but on the suction being increased, fuel passes upwards through the tube 68, and its level around the tube falls uncovering more of the openings 74. In a modification, the valve 27 is replaced by a valve admitting air to the upper part of the float chamber, which has also a second small air inlet, the fuel supply being thus controlled by the pressure of air above the fuel. The air passage 75 opens into the upper part of the float chamber, and a second passage leads directly from the float chamber to the tube 52 at the level of the orifice 73, so that the fuel supply is affected by the stiction in the mixing-chamber.