Fluid injector supply system and method for operating same

Patent metadata

Field	Value
Publication number	US-10184436-B2
Application number	US-201514802162-A
Country	US
Kind code	B2
Filing date	Jul 17, 2015
Priority date	Jul 17, 2015
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

A fluid injection system includes a fluid injector assembly; a fluid conditioning module having an outlet port that is fluidly coupled to an inlet port of the fluid injector assembly; an injector assembly outlet conduit fluidly coupled to an outlet port of the fluid injector assembly and disposed downstream of the fluid injector assembly, the injector assembly outlet conduit defining a pressure measurement port and a flow-restricting orifice, the pressure measurement port being disposed upstream of the flow-restricting orifice along the direction of fluid flow through the fluid injector assembly; a pressure sensor fluidly coupled to the pressure measurement port; and a controller operatively coupled to the fluid conditioning module and the pressure sensor. The controller is configured to adjust a flowrate of a fluid through the injector assembly inlet conduit based on a pressure signal from the pressure sensor.

First claim

We claim:

1. A fluid injection system, comprising:
a fluid injector assembly;
a fluid conditioning module having an outlet port that is fluidly coupled to an inlet port of the fluid injector assembly via an injector assembly inlet conduit;
an injector assembly outlet conduit fluidly coupled to an outlet port of the fluid injector assembly and disposed downstream of the fluid injector assembly along a direction of fluid flow through the fluid injector assembly,
the injector assembly outlet conduit defining a pressure measurement port and a flow-restricting orifice, the pressure measurement port being disposed upstream of the flow-restricting orifice along the direction of fluid flow through the fluid injector assembly;
a pressure sensor fluidly coupled to the pressure measurement port; and
a controller operatively coupled to the fluid conditioning module and the pressure sensor, the controller being configured to adjust a flowrate of a fluid through the injector assembly inlet conduit based on a pressure signal from the pressure sensor.

2. The fluid injection system of claim 1 , wherein a flow area of the injector assembly outlet conduit at the flow-restricting orifice is less than a flow area of the injector assembly outlet conduit at the pressure measurement port.

3. The fluid injection system of claim 1 , wherein the controller is further configured to scale a difference between the pressure signal and a target pressure value by a proportional gain.

4. The fluid injection system of claim 1 , wherein the fluid conditioning module includes:
a motor system operatively coupled to the controller,
a recirculation pump operatively coupled to the motor system, an outlet of the recirculation pump being fluidly coupled to an inlet of the recirculation pump via a first filter,
a delivery pump operatively coupled to the motor system, an inlet of the delivery pump being fluidly coupled to an outlet of the first filter, an outlet of the delivery pump being fluidly coupled to the injector assembly inlet conduit.

5. The fluid injection system of claim 4 , wherein the outlet of the delivery pump is fluidly coupled to the injector assembly inlet conduit via a second filter.

6. The fluid injection system of claim 4 , wherein the controller is further configured to adjust the flowrate of the fluid through the injector assembly inlet conduit by adjusting a speed of the motor system.

7. The fluid injection system of claim 4 , wherein the motor system includes a first motor operatively coupled to the delivery pump via a first shaft, the controller being further configured to adjust a speed of the first motor.

8. The fluid injection system of claim 7 , wherein the recirculation pump is operatively coupled to the first motor via a second shaft.

9. The fluid injection system of claim 7 , wherein the motor system further includes a second motor operatively coupled to the recirculation pump via a second shaft, the second motor being distinct from the first motor, the controller being further configured to operate the second motor at a constant speed.

10. The fluid injection system of claim 7 , wherein the delivery pump is a positive displacement pump.

11. The fluid injection system of claim 1 , further comprising a return conduit in fluid communication with an outlet of the flow-restricting orifice and a reservoir, wherein an elevated portion of the return conduit is disposed at an elevation that is higher than a highest fluid elevation within the fluid injector assembly with respect to a gravity direction.

12. The fluid injection system of claim 11 , wherein the elevated portion of the return conduit is disposed at an elevation that is at least one inch higher than the highest fluid elevation within the fluid injector assembly with respect to the gravity direction.

13. The fluid injection system of claim 1 , wherein the fluid injector assembly is a fuel injection assembly for a reciprocating internal combustion engine.

14. The fluid injection system of claim 1 , wherein the fluid injector assembly is an exhaust aftertreatment fluid injection assembly that is fluidly coupled to an exhaust duct of the internal combustion engine.

15. The fluid injection system of claim 4 , wherein the controller is further configured to effect a flowrate through the recirculation pump that is greater than a flowrate through the delivery pump.

16. A machine, comprising:
an internal combustion engine; and
a fluid injection system operatively coupled to the internal combustion engine, the fluid injection system including
a fluid injector assembly having at least one fluid injector in fluid communication with the internal combustion engine;
a fluid conditioning module having an outlet port that is fluidly coupled to an inlet port of the fluid injector assembly via an injector assembly inlet conduit;
an injector assembly outlet conduit fluidly coupled to an outlet port of the fluid injector assembly and disposed downstream of the fluid injector assembly along a direction of fluid flow through the fluid injector assembly,
the injector assembly outlet conduit defining a pressure measurement port and a flow-restricting orifice, the pressure measurement port being disposed upstream of the flow-restricting orifice along the direction of fluid flow through the fluid injector assembly;
a pressure sensor fluidly coupled to the pressure measurement port; and
a controller operatively coupled to the fluid conditioning module and the pressure sensor, the controller being configured to adjust a flowrate of a fluid through the injector assembly inlet conduit based on a pressure signal from the pressure sensor.

17. The machine according to claim 16 , wherein the at least one fluid injector is a plurality of fuel injectors, and each fuel injector of the plurality of fuel injectors is fluidly coupled to a combustion chamber of the internal combustion engine.

18. The machine according to claim 16 , wherein the engine includes an exhaust duct, the at least one fluid injector is at least one exhaust aftertreatment fluid injector, and the at least one exhaust aftertreatment fluid injector is fluidly coupled to the exhaust duct.

19. A method for operating a fluid conditioning system, the fluid conditioning system including
a fluid injector assembly;
a fluid conditioning module having an outlet port that is fluidly coupled to an inlet port of the fluid injector assembly via an injector assembly inlet conduit;
an injector assembly outlet conduit fluidly coupled to an outlet port of the fluid injector assembly and disposed downstream of the fluid injector assembly along a direction of fluid flow through the fluid injector assembly,
the injector assembly outlet conduit defining a pressure measurement port and a flow-restricting orifice, the pressure measurement port being disposed upstream of the flow-restricting orifice along the direction of fluid flow through the fluid injector assembly; and
a pressure sensor fluidly coupled to the pressure measurement port,
the method comprising:
receiving within a controller a pressure signal from the pressure sensor;
generating within the controller a control signal based on the pressure signal;
adjusting a flowrate of a fluid through the injector assembly inlet conduit by transmitting the control signal from the controller to the fluid conditioning module.

20. The method of claim 19 , wherein the generating the control signal based on the pressure signal includes scaling a difference between the pressure signal and a targe

Assignees

• Caterpillar Inc

Inventors

• Shafer Scott F
• Lehman Martin
• Wang Lifeng
• Hackett David E
• Tang Taylor
• Marrack Andrew
• Gibson Dennis H

Classifications

• F02M37/0047

  Layout or arrangement of systems for feeding fuel (fuel injection apparatus characterised by their conduits and venting means F02M55/00; fuel injection apparatus having a common rail F02M63/0225; arrangement of fuel conduits of low pressure fuel injection apparatus F02M69/462) · CPC title

• F02D41/3082

  Control of electrical fuel pumps · CPC title

• F02M37/0052

  Details on the fuel return circuit; Arrangement of pressure regulators · CPC title

• F02D2200/0602

  Fuel pressure · CPC title

• F02M2037/087

  Controlling fuel pressure valve · CPC title