GB105252A - A New or Improved Internal-combustion Engine Fuel System. - Google Patents

Abstract

105,252. Morgan, W., and Mills, W. March 31, 1916. Two-stroke-cycle engines; pumps, ports and passages of.-In fuel-supply systems in which the fuel is delivered from a nozzle by a difference of gaseous pressures created by the engine, through a conduit different from that through which the fuel thus delivered is conveyed by a pump, this pump, which does not affect the fuel delivery from the nozzle, is adapted to convey not only the fuel but also a quantity of gaseous carrying medium therefor. The fuel is admitted through a nozzle b to a chamber a, in which a depression is produced through a conduit c, which enters a constricted portion n of a pipe d through which atmospheric air is delivered to the crank chamber or other pump space, whence it is supplied to the cylinder. The area of the constriction n and of the nozzle b may be varied automatically and simultaneously. To ensure that a depression shall be produced in the pipe d, its inlet end o is provided with an automatic valve p, which is kept normally closed by a spring q, the pipe being provided also with a throttle valve u, and with a mechanically-actuated rotary valve v in the case of a two-stroke engine. The chamber a has a conical bottom, through a restricted aperture in which the fuel flows to a chamber j, whence it is drawn into the pump e and delivered, along with a carrying-medium such as air, exhaust, or other inert gas, through a port m into the cylinder f<1>. The carrying-medium may be admitted to the chamber a or j or to the pump. The inlet and outelt ports f, g of the pump are formed in the piston and are so situated that the motion and delivery are delayed, and made more vigorous so as to facilitate mixing of the fuel and its carrying-medium. A relief valve k allows excess fuel and carrying-medium to escape into a chamber l whence it is returned to the pump inlet, the chamber l, in conjunction with the restricted orifice, serving also as a damping space to prevent disturbance by the pump of the pressure conditions in the chamber a. For this purpose also, the pipe c at its junction with the chamber a, may be flared to ensure a low velocity of the entering air. The pump may be timed relatively to the engine piston, and whilst the engine is running. The fuel may be supplied by positive pressure, for example that of the exhaust gases acting upon the fuel in the float chamber. In a modification, the nozzle is situated in the air-pipe d and delivers fuel into a cup which faces the current of air, the mixture being passed through a vaporizer before entering the pump chamber. A vaporizer may be provided in the chamber j or in the conduit m. The fuel with its carrying-medium, may be injected directly into the cylinder, as shown, after the main air admission ports have been closed, but before the piston has completed its compression stroke; or it may be injected into the induction pipe or into the transfer passage near the inlet valve. The non- pressure side of the pump may be in communication with the air induction system to utilize leaking fuel. Multiple jets and chambers may be provided in the case of multicylinder engines. The Provisional Specification states that the fuel from the jet-chamber may be drawn directly into the cylinder through a valve the opening of which is delayed to produce suction, or it may be led to the seat of a poppet valve and fed to the cylinder by the induction action of the entering air.