GB1476629A - Fuel injection pumping apparatus - Google Patents

Abstract

1476629 Fuel injection pumps CAV Ltd 10 July 1974 [20 July 1973] 34694/73 Heading F1A In a rotary distributer type fuel injection pump, the quantity of fuel delivered to a respective outlet port 17 during the inward pumping strokes of plungers 12 is controlled by a spill valve 23 mounted in the distributer member 11, the spill valve 23 being operated by a cam ring 27 adjustably mounted in the pump body 10. Fuel displaced by the plungers 12 flows to the outlet ports 17 through passages 15, 16, the pressure in the passage 15 acting on a plunger 25 to seat the valve's head 24 until the plunger 25 is moved radially inwardly by the cam ring 27. Angular adjustment of the ring 27 is caused by axial displacement of a member 30, the latter having an inclined slot (29), Fig. 2 (not shown) which receives a peg 28 on the ring 27. The member 30 is slidable in a bore in a timing control ring 14 having lobes for reciprocating the plungers 12 and a fluid operated piston 21 for adjusting its angular position. Thus angular adjustment of the timing ring 14 also adjusts the quantity control cam ring 27. A spring 31 urges the member 30 towards the maximum delivery position, a lever 35 pivoted at 36 being acted upon by the sleeve 34 of a speed responsive device 32 to adjust the member 30. A further spring (not shown) acts on the lever 35 with a force dependent on the position of an operator controlled member, the operator thereby controlling the amount of fuel delivered.