Venturi fluid pump with outlet flow controller
A fuel pump for a fuel system includes a nozzle, a venturi, a pump inlet and a flow controller. The nozzle has an orifice through which fuel is ejected and the venturi is downstream of the nozzle and has an inlet through which fuel discharged from the orifice flows, a passage downstream of the venturi inlet through which fuel flows to create a drop in pressure in the area of the venturi, and an outlet through which fuel is discharged from the venturi. Fuel is drawn through the pump inlet by the drop in the pressure created in the area of the venturi and the flow controller is downstream of the outlet and has a chamber in which fuel from the venturi outlet is received. The flow controller causes fuel to fill the venturi to ensure performance of the fuel pump.
1. A fuel pump assembly for a fuel tank with an interior, comprising:
a fuel pump having an inlet through which fuel enters the fuel pump and an outlet through which fuel is discharged under pressure for delivery to an engine;
a nozzle having an inlet in communication with the outlet of the fuel pump through which fuel is discharged under pressure so that at least some of the fuel under pressure discharged from the fuel pump outlet flows into the nozzle inlet, the nozzle also having an orifice through which fuel is ejected from the nozzle;
a venturi downstream of the nozzle and having an inlet through which fuel discharged from the orifice flows, a passage downstream of the inlet through which fuel flows to create a drop in pressure, and an outlet through which fuel is discharged from the venturi;
a mounting flange configured to be carried by the fuel tank and disposing the nozzle, orifice, venturi inlet, passage, and outlet in a top portion of the interior of the fuel tank;
a fuel inlet through which fuel is drawn from the fuel tank into the venturi passage by the drop in the pressure created in an area of the venturi;
a flow controller downstream of the venturi outlet and having an inlet into which at least some of the fuel discharged from the venturi outlet is directed, an outlet, and an inclined surface oriented at an angle between 10 degrees and 90 degrees relative to a direction of fuel flow through the venturi outlet to direct fuel to the outlet of the flow controller;
the outlet of the flow controller is disposed above the venturi outlet relative to the direction of gravity so that fuel exits the flow controller outlet at a location above the outlet of the venturi passage to thereby improve the pressure drop generated in the area of the venturi;
a fuel reservoir in the interior of the fuel tank and having an interval volume; and
the fuel pump inlet communicating with the internal volume of the fuel reservoir and the outlet of the flow controller communicating with the internal volume of the fuel reservoir adjacent the top portion of the fuel tank, wherein the fuel reservoir is coupled to the mounting flange and wherein the nozzle, venturi and flow controller are carried by the mounting flange separately from the fuel reservoir and located within the internal volume of the fuel reservoir.
2. The fuel pump assembly of claim 1 wherein a flow rate of fuel through the flow controller outlet is low enough to permit the venturi to be filled with fuel in any orientation of the flow controller outlet.
3. The fuel pump assembly of claim 1 wherein the venturi is configured to communicate with the fuel tank through the fuel inlet and fuel discharged from the venturi flows into the internal volume of the reservoir.
4. The fuel pump assembly of claim 3 wherein the mounting flange is coupled to the reservoir, and the flow controller includes a connection feature coupled to the mounting flange.
5. The fuel pump assembly of claim 4 wherein the outlet of the flow controller is defined by one or more gaps between the flow controller and the mounting flange so that fuel exits the flow controller between the flow controller and the mounting flange and enters the reservoir internal volume.
6. The fuel pump assembly of claim 1 wherein the flow controller includes a chamber aligned with the venturi passage and the inclined surface defines part of the chamber.
7. The fuel pump assembly of claim 6 wherein a flow of fuel against the inclined surface causes fuel to fill the chamber to fully wet the venturi passage and prevent an air gap through the venturi passage.
8. The fuel pump assembly of claim 6 wherein the outlet of the flow controller is located between 2 mm and 20 mm above a top of the venturi passage.
9. The fuel pump assembly of claim 1 wherein the outlet of the flow controller is defined by one or more gaps between the flow controller and the mounting flange so that fuel exits the flow controller between the flow controller and the mounting flange and enters a reservoir internal volume.
10. The fuel pump assembly of claim 1 wherein when a flow rate out of the nozzle orifice reaches 5 liters per hour, fuel in the flow controller fully wets the outlet of the venturi.
11. The fuel pump assembly of claim 1 wherein the venturi passage is elongate and configured with an axis which is perpendicular to a force of gravity acting on fuel in the venturi passage.
12. The fuel pump assembly of claim 1 which also includes a housing that is carried by or formed in one-piece with the mounting flange, and wherein at least one of the nozzle, venturi and flow controller is carried by the housing separately from the fuel reservoir.
13. The fuel pump assembly of claim 12 wherein the housing includes an inlet that is coupled to the outlet of the fuel pump, and a fuel passage that communicates with the housing inlet and with the nozzle, and wherein the nozzle is fixed to the housing.
14. The fuel pump assembly of claim 12 wherein the nozzle is coupled to the housing, the venturi is coupled to the housing, and the flow controller is coupled to the venturi and the mounting flange.
15. A fuel pump assembly for a fuel tank with an interior, comprising:
a fuel pump having an inlet through which fuel enters the fuel pump and an outlet through which fuel is discharged under pressure for delivery to an engine;
a nozzle having an inlet in communication with the outlet of the fuel pump and an orifice through which fuel is ejected from the nozzle;
a venturi downstream of the nozzle and having an inlet through which fuel discharged from the orifice flows, a passage downstream of the inlet through which fuel flows to create a drop in pressure, and an outlet through which fuel is discharged from the venturi;
a mounting flange configured to be carried by the fuel tank and disposing the nozzle, orifice, venturi inlet, passage, and outlet in a top portion of the interior of the fuel tank;
a fuel inlet through which fuel is drawn from the fuel tank into the venturi passage;
a flow controller downstream of the venturi outlet and having an inlet into which at least some of the fuel discharged from the venturi outlet is directed, an outlet, and an inclined surface oriented at an angle between 10 degrees and 90 degrees relative to a direction of fuel flow through the venturi outlet to direct fuel to the outlet of the flow controller, the outlet of the flow controller is disposed above the venturi outlet relative to the direction of gravity so that fuel exits the flow controller outlet at a location above the outlet of the venturi passage;
a fuel reservoir in the interior of the fuel tank and having an interval volume; and
the fuel pump inlet communicating with the internal volume of the fuel reservoir and the outlet of the flow controller communicating with the internal volume of the fuel reservoir adjacent the top portion of the fuel tank, wherein the fuel reservoir is coupled to the mounting flange and wherein at least one of the nozzle, venturi and flow controller are carried by the mounting flange separately from the fuel reservoir and located within the internal volume of the fuel reservoir.