Patent GB-718083-A (GB)
Title: Improvements in fuel injection apparatus for internal combustion engines
IPC: F02M59/10
Filed: 1952-08-15
Abstract: 718,083. Fuel injection systems. FRENCH, L O. Aug. 15, 1952 [Nov. 21, 1951], No. 20558/52. Class 7(3) A piston 6, Fig. 1. reciprocating in a' cylinder 7 and moved outwardly of the combustion chamber C of an I.C. engine by compression pressure is rigid with a fuel pump barrel 19 working on a stationary plunger 48 and having a fuel discharge conduit extension 9 for receiving fuel at pump injection pressure, a fixed spray orifice 8 communicates with the chamber C, and the extension 9 has an outlet 67 in constant communication with the orifice 8 to conduct fuel at injection pressure thereto during the outward movement of the piston 6. The pressure in the engine cylinder is transmitted to the piston 6 through passages 68. As the piston is raised fuel is delivered by the plunger 48 past non-return valves 28, .30 and through a passage 66 in the extension 9 to the outlet 67. Timing and cushioning of the piston 6 may be according to Specification 651,483. The piston 6 and a checking piston 20 are-urged downwardly by a spring 51 and the pressure in a space 46 which comprises a non-return valve controlled inlet 52 and a variable pressure relief valve controlled outlet 53. The piston 20 laps the outlet for checking the final movement of the assembly. The delivery of the plunger can be varied by turning it by means of a lever 57 and thus varying the position of an inclined port 58 with respect to a relief port 43. The pump inlet port is indicated at 40. In compression ignition engines the fuel also acts as a coolant and enters at 38 and leaves at 39. Where fuel is not used as the coolant, passages connect the parts 40, 43 to the chamber 46. The piston 6 may be bored out at 18b for a coolant. A ring 56 of neoprene or silicone rubber composition is engaged by the top of the piston 6 at the end of the upward stroke. A key slot 35 co-operates with a pin 36 on the cylinder 7. The parts 6 and 20 are preferably of light metal such as aluminium or titanium. A water jacket space 16 either forms part of or is connected to the main jacket space of the head. The invention is applicable to variable stroke injectors for example the injector described in Specification 651,483. The surface 69 of the extension 9, Fig. 2, may be broken up into two conical surfaces 69a, 69b as shown in Fig. 4. Fig. 3 shows a modification in which a cylindrical pin 72 is employed. Some fuel may discharge between the orifice 73 and the pin and some through orifices 76. In Fig. 4 a groove 77 is provided so that at the same time as or after the initial direct injection of the charge through the orifice 64 fuel will be injected in the chamber 78. This injection may start at about half stroke of the piston or before or after half stroke. This produces a flow from the chamber 78 through the groove and an enlargement 65 and the orifice 64 which disperses the fuel through the orifice 64. The passages 79 corresponding to the passages 68, Fig. 2, may be open or as shown may be controlled by a non-return valve 80. The valve has serrations or grooves 81. In a further modification similar to Fig. 4 the pin has a cylindrical end similar to that shown in Fig. 3. The member 8 may be integral with the cylinder head. It is stated that use of cheaper fuel is permitted by the type of injector shown in Fig. 4. The invention is applicable to spark ignition volatile fuel engines such as high compression (12 to 1) engines.