GB475603A - Improvements in or relating to internal combustion engine-electric power units - Google Patents

Abstract

475,603. Fluid - pressure servomotor - control systems. SULZER FRERES SOC. ANON. Oct. 2, 1936, No. 26808. Convention date, Feb. 12. [Class 135] An internal-combustion engine electric power unit of the kind having apparatus for setting the speed at which the engine is to operate and means which tend to maintain the engine torque constant for any given speed has the speed controlled device controlling the quantity of fuel injected also adapted to control the timing of the commencement of the fuel injection. In the arrangement shown in Fig. 1, a centrifugal governor 9 driven by bevel gearing 8 from an engine driven shaft 7 operates a threearmed lever 11 coupled by a link 12 with the rack 13 for adjusting the fuel pump plungers and coupled by a link 15 with a lever 16 operating a piston valve 18 controlling the operation of a servomotor 19 connected to the movable arm of a rheostat 22 in the field circuit of an electric generator coupled to the engine. The governor is adjustably loaded by a spring 25 bearing against a movable abutment 26 operated by a screw 31 working through a nut rotatable by a hand wheel acting through bevel gear. The upper part of the screwed spindle 31 is squared to prevent its rotation and is pinned to a lever 34 carrying the fulcrum 17 for the lever 16 so that the governor loading and the effective length of the link 15 and thus the basic fuel setting are -simultaneously varied. The fuel pumps comprise plungers 39 reciprocated against the action of springs 40 by cams 36 on the shaft 7 to co - operate with inlet ports 41 and force oil through discharge valves 42. The top of the plungers have inclined edges 43 which when they pass over the ports 41 determine the commencement of the discharge and edges 44 which as they open up the ports 41 to the byepass 45 determine the end of the discharge. To vary the commencement and duration of the discharge, the plungers are rotated by a rack 13 engaging pinions 47 which have slotted bosses co-operating with lugs 48 on the pump plungers. In a modification, a servomotor with a floating lever follow-up gear is employed for operating the rack 13 and the fulcrum of the lever 16 is adjusted by a sliding cam coupled by a link and bell-crank lever to the rod 31. The setting of the governor loading spring may be effected hydraulically, pneumatically, electrically or magnetically. The commencement of fuel injection and the quantity of fuel injected may be controlled by two control devices such as a suction valve and a byepass valve. These two variables may be controlled by a single byepass valve operated by a cam adapted to be adjusted axially. One or both of the inclined control edges of the fuel pump may be on a sleeve surrounding the plunger.