GB694966A - Improvements in fuel injection pumps - Google Patents

Abstract

694,966. Fuel-injection pumps. HOBSON, Ltd., H. M. Aug. 14, 1951 [Aug. 25. 1950], No. 21072/50. Class 102 (i). In a fuel injection pump, the piston 32 is reciprocated by the cam 34 and rotated from a pinion 37 on the camshaft so that an axial groove 52 in the piston registers in turn with a number of outlets connected to the engine cylinders. The delivery ports 49 are at a different level in the cylinder to the suction ports 48 and delivery commences when the trailing edge of the groove 52 closes a suction port and ends when a groove 53 in the piston opens the suction ports 48. To vary the delivery and beginning of injection, the phase of rotation of the plunger relative to the camshaft is varied by arranging that the driving sleeve 39 rotated by the pinion 37 is splined at 40 to a slider 41 which has internal inclined grooves 42 engaged by members 43 attached to a plunger guide 44 that has slots 45 engaged by pins 46 on the plunger; the slider 41 is adjusted axially by a lever 54. Alternatively the pump barrel 31 may be adjusted by rotation. The beginning of injection may be constant and the end varied bv varying the phase of the reciprocation of the piston relatively to the camshaft by rotation of the cam 34 on the shaft 36. In a modified construction, the groove 53 is omitted and the end of injection is determined by the groove 52 opening the vent adjacent suction port. Specification 647.687 is referred to.