Liquid fuel injection pumping apparatus

Claim 2

A liquid fuel injection pumping apparatus comprising an injection pump including a control element movable to adjust the quantity of fuel supplied by the injection pump at each injection stroke thereof, a centrifugal weight mechanism adapted to be driven at a speed which varies in accordance with the speed at which the associated engine is operating, a member movable by the weight mechanism, resilient means for resisting movement of the member by the weight, a lever which is pivotally connected to the member and the control element at spaced positions, and manually operable means for effecting movement of the lever about one or the other of its pivots to determine the setting of said control element, the improvement being that said resilient means comprises an idling spring and a pair of springs, said idling spring and said pair of springs being positioned in series with each other and acting against said member to resist movement thereof by said centrifugal weight mechanism, means limiting the extent of deflection of said idling spring whereby said idling spring is effective in conjunction with the weight mechanism to control the output of the pump only during idling of the engine, means pre-loading one of said pair of springs so that deflection of said one spring by said weight mechanism occurs only when the engine speed attains a predetermined value, deflection of said one spring irrespective of the setting of said manually operable means allowing movement of said member to reduce the amount of fuel supplied to the engine so as to limit the maximum speed of the engine, the other of said springs being deflected by said weight mechanism at a lower engine speed than said predetermined value, whereby with increasing speeds below said predetermined value depending upon the setting of said manually operable means there will be a gradual reduction in the amount of fuel supplied to the engine.

Claim 3

The apparatus as claimed in claim 1 wherein said one spring comprises a coiled compression spring and said other spring comprises a leaf spring which is pivotally mounted at one end and which, at its other end, engages said member through said idling spring.

Claim 4

The apparatus as claimed in claim 2 in which the coiled compression spring engages one face of the leaf spring intermediate the ends thereof, means being provided which engages the opposite surface of the leaf spring, for pre-loading the coiled compression spring.

Claim 5

The apparatus as claimed in claim 3 in which said means comprises a T shaped member having a shank portion extending through an aperture in the leaf spring, the head of the T-shaped member engaging said opposite surface of the leaf spring, the shank portion of the T-shaped member extending within the coiled compression spring and being of adjustable length to determine the pre-load of the compression spring.

Claim 6

A liquid fuel injection pumping apparatus comprising an injection pump including a control element movable to adjust the quantity of fuel supplied by the injection pump at each injection stroke thereof, a centrifugal weight mechanism adapted to be driven at a speed which varies in accordance with the speed at which the associated engine is operating, a member movable by the weight mechanism, resilient means for resisting movement of the member by the weight, a lever which is pivotally connected to the member and the control element at spaced positions, and manually operable means for effecting movement of the lever about one or the other of its pivots to determine the setting of said control element, the improvement being that said resilient means comprises an idling spring and a pair of springs, said idling spring and said pair of springs being positioned in series with each other and acting against said member to resist movement thereof by said centrifugal weight mechanism, means limiting the extent of deflection of said idling spring whereby said idling spring is effective in conjunction with the weight mechanism to control the output of the pump only during idling of the engine, means preloading one of said pair of springs so that deflection of said one spring by said weight mechanism occurs only when the engine speed attains a predetermined value, deflection of said one spring irrespective of the setting of said manually operable means allowing movement of said member to reduce the amount of fuel supplied to the engine so as to limit the maximum speed of the engine, the other of said springs being deflected by said weight mechanism at a lower engine speed than said pre-determined value, whereby with increasing speeds below said pre-determined value depending upon the setting of said manually operable means there will be a gradual reduction in the amount of fuel supplied to the engine, said pair of springs being defined by a single leaf spring which at one end is pivotally mounted about a fixed point, the other end of the spring bearing against said member, there being provided a fixed stop engaging the spring at a position spaced from said other end thereof, and an adjustable stop engaging the spring intermediate said one end thereof and said fixed stop and said member constituting said other spring.

Claim 7

A liquid fuel injection pumping apparatus comprising an injection pump including a control element movable to adjust the quantity of fuel supplied by the injection pump at each injection stroke thereof, a centrifugal weight mechanism adapted to be driven at a speed which varies in accordance with the speed at which the associated engine is operating, a member movable by the weight mechanism, resilient means for resisting movement of the member by the weight, a lever which is pivotally connected to the member and the control element at spaced positions, and manually operable means for effecting movement of the lever about one or the other of its pivots to determine the setting of said control element, the improvement being that said resilient means comprises an idling spring and a pair of springs, said idling spring and said pair of springs being positioned in series with each other and acting against said member to resist movement thereof by said centrifugal weight mechanism, means limiting the extent of deflection of said idling spring whereby said idling spring is effective in conjunction with the weight mechanism to control the output of the pump only during idling of the engine, means preloading one of said pair of springs so that deflection of said one spring by said weight mechanism occurs only when the engine speed attains a predetermined value, deflection of said one spring irrespective of the setting of said manually operable means allowing movement of said member to reduce the amount of fuel supplied to the engine so as to limit the maximum speed of the engine, the other of said springs being deflected by said weight mechanism at a lower engine speed than said pre-determined value, whereby with increasing speeds below said pre-determined value depending upon the setting of said manually operable means there will be a gradual reduction in the amount of fuel supplied to the engine, said pair of springs being defined by a single leaf spring which at one end is pivotally mounted about a fixed point, the other end of the spring bearing against said member, there being provided a fixed stop engaging the spring at a position spaced from said other end thereof, and an adjustable stop engaging the spring intermediate said one end thereof and said fixed stop and said member constituting said other spring.

Claim 8

The apparatus as claimed in claim 5 in which said adjustable stop comprises a pin carried by a plate pivotable about said fixed point.