GB373602A - Improvements in and relating to the controlling of fuel injection pumps of internal combustion engines - Google Patents

Abstract

373,602. Fuel injection pumps. BOSCH AKT.-GES., R., 4, Militõrstrasse, Stuttgart, Germany. Nov. 24, 1930, No. 4976. Convention date, Nov. 23, 1929. [Class 102 (i).] An arrangement for controlling a predetermined maximum speed of an internalcombustion engine in which a controlling element situated in the fuel supply system diminishes the effective quantity of fuel supplied upon an increase in pressure difference between two selected points in the fuel supply system. Fig. 1 shows a piston body 31 provided with a throttling passage 32 and integral with the delivery valve 20. Upon an increase in speed, the fuel is stored beneath the piston until the plunger 14 nears the end of its delivery stroke when the stored fuel is byepassed to the suction inlet 17 through grooves 29, 30. Fig. 3 shows the controlling element arranged in the fuel delivery pipe and comprises a piston body 59 provided with a throttle plate 72 and ports 65 aligned with ports 67. Upon increase in speed the piston body is raised against the spring 62 and ports 66 align with ports 68 thus byepassing the fuel to the suction tank 18. Fig. 2 shows a pump for an engine with a plurality of cylinders wherein the delivery valve 20 of one pump cylinder is provided with a cylindrical extension and a throttle plate 49. Upon an increase in speed, the fuel is byepassed through port 50 to a chamber 52 provided with a piston 53 and a throttle passage 54 leading to suction. The piston 53 is connected by a link 55 i;o a rack 48 gearing with all the pump plungers, which are provided with inclined grooves 47 which vary the time of byepassing to suction. The maximum engine speed may be adjusted by varying the loading of the springs or varying the size of the throttle passage. The throttle may be replaced by a Venturi tube. Specifications 278,686 and 291,051, [both in Class 102 (i), Pumps &c.], are referred to. The Specification as open to inspection under Sect. 91 (3) (a) comprises also a construction wherein a relief valve is arranged on the pump cylinder causing a byepass to suction. In a further construction a piston body 21 is fitted with a throttle passage 37 and located in the pump suction. One end of the body is acted upon by atmospheric pressure and the other end by the pump suction and a spring 24. Excessive suction causes the body to move and throttle the passage 36. This subject-matter does not appear in the Specification as accepted.