DIRECT INJECTION FUEL PUMP

• US 20140224217A1
• Filed: 03/14/2013
• Published: 08/14/2014
• Est. Priority Date: 02/12/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Pursifull, Ross Dykstra, Ulrey, Joseph Norman, Surnilla, Gopichandra, Basmaji, Joseph F., Meinhart, Mark
• Granted Patent: US 9,422,898 B2
• Time in Patent Office: Days
• US Class Current: 123/446
• CPC Class Codes: F02D 41/3094 the fuel injection being effected by at least two different injectors, e.g. one in the intake manifold and one in the cylinder
• CPC Class Codes: F02D 41/3845 by controlling the flow into the common rail, e.g. the amount of fuel pumped
• CPC Class Codes: F02M 2200/315 for damping fuel pressure fluctuations
• CPC Class Codes: F02M 37/0047 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 Class Codes: F02M 39/005 Arrangements of fuel feed-pumps with respect to fuel injection apparatus F02M37/00 takes precedence
• CPC Class Codes: F02M 41/125 Variably-timed valves controlling fuel passages
• CPC Class Codes: F02M 41/1427 Arrangements for metering fuel admitted to pumping chambers, e.g. by shuttles or by throttle-valves
• CPC Class Codes: F02M 59/102 Mechanical drive, e.g. tappets or cams F02M45/063 takes precedence
• CPC Class Codes: F02M 59/34 by throttling of passages to pumping elements or of overflow passages , e.g. throttling by means of a pressure-controlled sliding valve having liquid stop or abutment
• CPC Class Codes: F02M 59/368 Pump inlet valves being closed when actuated
• CPC Class Codes: F02M 59/462 Delivery valves
• CPC Class Codes: F02M 59/464 Inlet valves of the check valve type
• CPC Class Codes: F02M 63/0001 Fuel-injection apparatus with specially arranged lubricating system, e.g. by fuel oil lubrication of engines F01M

Abstract

Methods and systems are provided for a direct injection fuel pump. The methods and system control pressure within a compression chamber so as to improve fuel pump lubrication.

Claims

1. A method of operating a direct injection fuel pump, comprising:

regulating a pressure in a compression chamber of the direct injection fuel pump to a single pressure during a direct injection fuel pump compression stroke, the pressure greater than an output pressure of a low pressure pump supplying fuel to the direct injection fuel pump.

2. The method of claim 1, where the pressure provides a differential pressure greater than a threshold differential pressure between the piston'"'"'s top and bottom during the direct injection fuel pump compression stroke.

3. The method of claim 1, where an outlet pressure of the direct injection fuel pump is maintained at a pressure during the direct injection fuel pump compression stroke.

4. The method of claim 1, where the pressure is regulated via a pressure relief valve.

5. The method of claim 1, further comprising ceasing fuel flow from the direct injection fuel pump to an engine during the direct injection fuel pump compression stroke.

6. The method of claim 1, further comprising commanding a solenoid activated check valve at an inlet of the direct injection fuel pump to a pass-through state during the direct injection fuel pump compression stroke.

7. The method of claim 1, where the direct injection fuel pump is driven via a cam.

8. A method of operating a fuel pump, comprising:

regulating a pressure in a compression chamber of the direct injection fuel pump to a single pressure during direct injection fuel pump compression and suction strokes, the pressure greater than an output pressure of a low pressure pump supplying fuel to the direct injection fuel pump.

9. The method of claim 8, where the single pressure is substantially constant.

10. The method of claim 8, where an accumulator provides fuel to the compression chamber during the suction stroke.

11. The method of claim 10, where the accumulator stores fuel from the compression chamber during the compression stroke.

12. The method of claim 8, where the pressure provides a differential pressure greater than a threshold differential pressure between the piston'"'"'s top and bottom during the direct injection fuel pump suction stroke.

13. The method of claim 8, where an outlet pressure of the direct injection fuel pump is maintained at a pressure during the direct injection fuel pump compression stroke.

14. The method of claim 8, where the pressure is regulated via a pressure relief valve.

15. A direct injection fuel pump system, comprising:

a direct injection fuel pump including a piston, compression chamber, a cam for moving the piston, a solenoid activated check valve positioned at an inlet of the direct injection fuel pump, and a pressure relief valve positioned upstream of the solenoid actuated check valve and biased to regulate pressure in the compression chamber.

16. The direct injection fuel pump system of claim 15, further comprising an accumulator positioned between the check valve and the solenoid activated check valve.

17. The direct injection fuel pump system of claim 15, further comprising a check valve positioned in parallel with the pressure relief valve.

18. The direct injection fuel pump system of claim 15, further comprising a controller including instructions to operate the solenoid activated check valve in a pass-through mode during deceleration of a vehicle.

19. The direct injection fuel pump system of claim 15, further comprising a controller including instructions to deactivate a fuel injector during deceleration of a vehicle.

20. The direct injection fuel pump system of claim 15, further comprising a cam for adjusting a position of the piston.