Fuel injection pump

Claim 1

A fuel injection pump for supplying fuel to an internal combustion engine comprising a pumping plunger which is positively reciprocated by a cam mechanism of the desmodromic type, the mechanism comprising a first cam follower located at one end of the plunger, the cam follower being engageable by a cam lobe on a rotary multilobe cam to impart inward movement to the plunger in a direction to pump fuel, a second cam follower engageable with a cam lobe, said second cam follower being mounted at one end of a first pivotal lever, the other end of the first pivotal lever being mounted on a housing of the pump, a second pivotal lever being pivotally mounted intermediate its ends on said housing, one end of said second pivotal lever engaging with said plunger and the other end of the second pivotal lever being operatively coupled to said first pivotal lever, so that movement of the second cam follower by the cam lobe will cause pivotal movement of the levers and outward movement of the plunger, adjustment means carried by one of said levers and engaging with the other of said levers whereby the backlash in the mechanism can be adjusted, said adjustment means comprising a wedge-shaped shoe adjustably mounted on said first lever, a surface defined on said shoe for engagement by the second lever and a bolt engaging said shoe and said first lever for securing the shoe to the first lever, the bolt having a head which engages with a further surface defined by the shoe, said further surface of the shoe being inclined to a surface defined on said first lever and against which the shoe is secured by the screw, whereby lateral movement of said shoe relative to the surface defined on said first lever will be restrained by a wedge action.