GB441512A - Improvements in or relating to fuel supply systems of internal combustion engines of the solid fuel injection compression ignition type - Google Patents

Abstract

441,512. Fuel - injection pumps. SULZER FRERES SOC. ANON., Winterthur, Switzerland. Nov. 26, 1934, No. 33955. Convention date, Dec. 4, 1933. [Class 102 (i)] [See also Group XXVII] In a compression-ignition internal-combustion engine, liquid fuel is supplied under pressure, applied by a pump or by a medium under pressure, through a preheating apparatus supplied with heat by the engine exhaust, to an injection pump. In the construction shown in Fig. 1, heavy oil, drawn from a reservoir 8 by a pump 10 is delivered to a tank 12 through a pipe 11, which passes through a jacket 17 connected to the engine water-cooling system, and flows through ribbed pipes 22 in the exhaust pipe 21 to an injection pump 2. The pressure on the fuel may be kept constant by an automatic pressure-relief valve 74 and additional pressure may be placed on the fuel in the tank 12 by connecting it through a pipe 26 to the compressed air supply used at starting. During starting, valves 24, 27 are opened to return the heavy oil through a pipe 23 to the reservoir 8 and to supply the injection pump 2 with light fuel from a tank 28. In a modified construction, Fig. 2, the pump 10 delivers fuel to a tank 33, surrounded by a jacket 34 connected to the engine water-cooling system, and the fuel is forced by a second pump 37 through a ribbed pipe 38, in the exhaust pipe 21, to the injection pump 2. At starting, while the engine is being run on a light fuel, the heated heavy fuel is passed through a pipe 55 into a heating jacket 60 around the pump 2 and returned through a pipe 59 to the tank 33. If desired, a valve 57 is operated to byepass the heating jacket around the pump. The degree of heating may be regulated by operating valves 41, 48, 49, 52 to allow the fuel to pass from the pipe 38 to the injection pump 2 through one or more ribbed pipes 46, 47 in the exhaust pipe 21. When either or both of the pipes 46, 47 is out of the fuel circuit it is evacuated of fuel by operating valves 65, 66, 67 to enable compressed air from a pipe 70 to blow the fuel through a pipe 69 back to the reservoir 8. The pressure applied to the fuel during preheating exceeds the evaporation pressure, at the preheating temperature, of the most volatile ingredient in the fuel and the temperature is such that the fuel has a viscosity less than 8‹ Engler.