GB1248039A - Liquid fuel injection pumping apparatus for supplying fuel to an internal combustion engine - Google Patents

Abstract

1,248,039. Reciprocating pumps. C.A.V. Ltd. Jan.21, 1969 [Feb.1, 1968], No.5138/68. Heading F1A. [Also in Division F2] In a fuel injection pump the plungers 41 are actuated in one direction by multilobed cams 15 and in the other by the pressure of fuel from a feed pump 22 which passes to the cylinders via a throttle valve, 65, Fig.2 (not shown). A groove 81 in each plunger is in constant communication with a groove 61 in the cylinder bore 40 which communicates with a bucket valve 82. The throttle valve 65 is movable in one direction by adjustable springs (72), (73) and in the other by a belt driven centrifugal mechanism 70. On the discharge stroke the plungers spill through ports 59 which may be closed by a manually actuated valve 60 to give excess fuel for starting. Injection is terminated when grooves 84 open to ports 59. Fuel pressure on the delivery stroke forces plug 57 of valve 56 into abutment with a valve body 53 and then valve 56 lifts to permit passage of fuel. Liquid in the delivery line is sucked back when the plug 57 and valve 56 return to their original position. The cam lobes act as bearing surfaces for the shaft 50 and engages the plungers 41, through intermediary tappet rollers 43, provision being made to allow rollers 43 to separate from the cams at the lowermost position of the plungers to facilitate lubrication of the working surfaces. A priming pump 30 is also provided having a hand actuated plunger 31. A bleed 91 is fitted to aleviate build up of gases in the pump.