US3557764A — Liquid fuel pumping apparatus

Claim 1

Independent Claim 311 words

A liquid pumping apparatus for supplying fuel to a compression ignition engine and comprising in combination, an accumulator for storing liquid fuel under pressure, an injection pump operable to deliver a metered quantity of fuel under pressure to the accumulator prior the to the delivery of fuel to the engine, a conduit extending from said accumulator to an outlet which outlet in use, is connected to a fuel nozzle disposed to direct fuel into a combustion space of the engine, first valve means operable in timed relationship with the engine and arranged when open, to permit flow of fuel through said conduit, second valve means in series with said first valve means, said second valve means being responsive to the pressure of fuel in the accumulator and arranged to open to permit flow of fuel through said conduit when the pressurE of fuel in the accumulator is above a predetermined value and to prevent flow through said conduit when the pressure in the accumulator falls to said predetermined value, and means whereby the quantity of fuel delivered by the injection pump can be adjusted, the arrangement being such that before the injection pump supplies fuel to the accumulator the pressure therein will be at said predetermined value a but after the supply of fuel the pressure will be at a higher value depending on the volume of fuel supplied by the injection pump, said first valve means following the supply of fuel by the injection pump being opened to permit flow of fuel through the conduit to the outlet, the flow of fuel through the conduit being halted by the closure of said second valve means when the pressure of fuel in the accumulator has fallen to said predetermined value, the volume of fuel flowing through to the outlet being equal to the volume of fuel supplied by the injection pump.

Claim 2

Dependent Claim 311 words

A liquid pumping apparatus for supplying fuel to a compression ignition engine and comprising in combination, an accumulator for storing liquid fuel under pressure, an injection pump operable to deliver a metered quantity of fuel under pressure to the accumulator prior the to the delivery of fuel to the engine, a conduit extending from said accumulator to an outlet which outlet in use, is connected to a fuel nozzle disposed to direct fuel into a combustion space of the engine, first valve means operable in timed relationship with the engine and arranged when open, to permit flow of fuel through said conduit, second valve means in series with said first valve means, said second valve means being responsive to the pressure of fuel in the accumulator and arranged to open to permit flow of fuel through said conduit when the pressurE of fuel in the accumulator is above a predetermined value and to prevent flow through said conduit when the pressure in the accumulator falls to said predetermined value, and means whereby the quantity of fuel delivered by the injection pump can be adjusted, the arrangement being such that before the injection pump supplies fuel to the accumulator the pressure therein will be at said predetermined value a but after the supply of fuel the pressure will be at a higher value depending on the volume of fuel supplied by the injection pump, said first valve means following the supply of fuel by the injection pump being opened to permit flow of fuel through the conduit to the outlet, the flow of fuel through the conduit being halted by the closure of said second valve means when the pressure of fuel in the accumulator has fallen to said predetermined value, the volume of fuel flowing through to the outlet being equal to the volume of fuel supplied by the injection pump.

Claim 3

Dependent Claim 59 words

A pumping apparatus as claimed in claim 1 in which said second valve means is positioned intermediate the accumulator and said first valve means, said second valve means when in the closed position acting to maintain the portion of the conduit downstream of the second valve means at a second predetermined pressure lower than said first mentioned predetermined pressure.

Claim 4

Dependent Claim 72 words

A pumping apparatus as claimed in claim 2 in which said first valve means constitutes a variable restricted orifice across which a varying pressure drop is developed during flow of fuel through the conduit, third valve means being provided and which is responsive to said pressure drop, said third valve means acting to control the rate of flow of fuel through said conduit in accordance with the magnitude of said pressure drop.

Claim 5

Dependent Claim 73 words

A pumping apparatus as claimed in claim 3 including a rotary distributor member mounted within a body part, said first valve means being constituted by a port and a groove formed in the body part and the distributor member respectively, there being formed in the distributor member and axial passage communicating with said groove and with a delivery passage, the delivery passage being positioned to register with an outlet in the body part.

Claim 6

Dependent Claim 35 words

An apparatus as claimed in claim 4 in which a plurality of said grooves and said outlets are provided whereby the apparatus can be used to supply fuel to the cylinders of a multicylinder engine.

Claim 7

Dependent Claim 193 words

An apparatus as claimed in claim 5 including supply means for supplying fluid under pressure and at a pressure which varies in accordance with the speed at which the apparatus is driven said second valve means comprising a spool movable within a cylinder an area at one end of the spool being exposed to said fluid pressure and a smaller area at the other end of the spool being subjected to the pressure within the accumulator, a pair of grooves defined on the spool, one of said grooves being in constant communication with the interior of the accumulator, and forming in conjunction with a port in the wall of the cylinder, part of said conduit, said port being uncovered to said one groove when the pressure within the accumulator is such as to move the spool against the action of said fluid pressure, the other groove serving to place a further pair of ports in the wall of the cylinder in communication with each other when the spool is moved against the action of the pressure in the accumulator, one of said ports being in communication with said passage of the distributor member.

Claim 8

Dependent Claim 27 words

An apparatus as claimed in claim 6 in which the other of said pair of ports communicates with a drain by way of a constant pressure valve.

Claim 9

Dependent Claim 38 words

An apparatus as claimed in claim 7 in which said grooves on the distributor member are of varying depth whereby the restriction imposed by the variable orifice depends upon the extent of registration of the groove and port.

Claim 10

Dependent Claim 32 words

An apparatus as claimed in claim 7 in which said grooves are helically disposed, and the distributor member is axially adjustabLe to determine the timing of delivery of fuel to the engine.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1974-01-25	1974-07-27	1975-01-26	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1978-01-25	1978-07-27	1979-01-26	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1982-01-25	1982-07-27	1983-01-26	$7700.00	Window Closed / Lapsed

Liquid fuel pumping apparatus

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