GB1324825A - Regulating devices for the flow of fuel in internal combustion engines - Google Patents

Abstract

1324825 Regulating I C engines SOC INDUSTRIELLE GENERALE DE MECHANIQUE APPLIQUEE 30 Dec 1970 [31 Dec 1969] 61856/70 Heading F1B [Also in Division G3] In a control mechanism for a fuel injection pump, centrifugal governor 4a Fig.9 responds to engine speed variations and pivots lever 23a about point 24 to displace a spool 22 controlling leakage at 50 from a large-area side of servopiston 32a whose half-area side is supplied by inlet 40a and accumulator 80 Fig.2 and connects with the fullarea side via orifice 41a. The servopiston thereby follows the spool movements to control the injection pump via rack 33a the movements of which are fed back to lever 23a by a lever 52, which pivots at 53, and a delay unit defined by piston 62 adapted to expel or draw fluid through restricted passage 75 when loaded by spring 68 through rod 65. The levers 23a, 52 return to parallel relation as the mechanism regains equilibrium. With pivot 53 on the same horizontal line as pivot 12a, the fullload engine speed equals the no-load speed, but by displacing the pivot 53 up or down in slot 57 the full-load speed will be respectively less than and greater than the no-load speed. In the practical embodiment of Figs.1 and 2, governor spring 10a is adjustable by axial adjustment of seat 13a by a toothed sector 16a, rotatable between stops (18a, 19a) corresponding to maximum and idling speeds, or by a shaft 48, rotatable by motor 49 or a handwheel. The lever 23a abuts the end of spool 22a and is also connected to the latter by spring 27a. Handle 28a allows manual over-ride control of the spool to move the rack leftwards to its minimum flow setting; as an alternative arrangement, a solenoid valve 102 Fig.7, (not shown) can be deenergized to prevent return flow via port 44a Fig.2 2 from the casing whereby the pressure builds up in servo-chamber 38a to displace piston 32a leftwards. In the idle position, the spool 29a abuts a stop 29a defining the fuel setting at start-up; this stop can alternatively be adjustable by a cam or an electromagnet Figs.5 and 6 (not shown). Plate 36a closing servo-chamber 38a is radially displaceable so that the spool 22a is guided solely by the servopiston.