Direct injection fuel pump

Patent metadata

Field	Value
Publication number	US-10006426-B2
Application number	US-201615235985-A
Country	US
Kind code	B2
Filing date	Aug 12, 2016
Priority date	Feb 12, 2013
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

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.

First claim

The invention claimed is:

1. A fuel system, comprising:
a direct injection fuel pump including a piston, a compression chamber, a piston stem, and a cam for driving the piston, wherein the piston and the piston stem have equal diameters;
a solenoid-activated check valve positioned at an inlet of the direct injection fuel pump for regulating fuel flow;
an accumulator positioned upstream of the solenoid-activated check valve; and
a check valve positioned upstream of the accumulator, wherein the accumulator adds a dead volume to a clearance volume of the direct injection fuel pump when the solenoid-activated check valve is in a deactivated state.

2. The fuel system of claim 1 , wherein the accumulator is a dead volume comprising a rigid container with a vacuous interior volume and no additional components.

3. The fuel system of claim 1 , wherein the piston stem consumes the volume of a step room located on a backside of the piston, allowing substantially no fuel to travel to or from a low pressure fuel line.

4. A fuel system, comprising:
a direct injection fuel pump including a piston, a compression chamber, a piston stein, and a cam for driving the piston, wherein the piston and the piston stein have equal diameters;
a solenoid-activated check valve positioned at an inlet of the direct injection fuel pump for regulating fuel flow;
an accumulator positioned upstream of the solenoid-activated check valve; and
a check valve positioned upstream of the accumulator that stops fuel from flowing from the direct injection fuel pump into a low pressure fuel line.

5. A direct injection fuel pump system, comprising:
a piston with an outside diameter;
a compression chamber;
a piston stern with an outside diameter equal in size to the outside diameter of the piston;
a cam for driving the piston; and
an accumulator positioned upstream of the direct injection fuel pump, no vacuous volume being present on a backside of the piston in between the piston and the piston stem throughout movement of the piston.

6. The direct injection fuel pump system of claim 5 , wherein the accumulator adds a dead volume to a clearance volume of the direct injection fuel pump when the solenoid-activated check valve is in a deactivated state.

7. The direct injection fuel pump system of claim 5 , wherein fuel pressurized by the piston in the compression chamber flows into the accumulator when the solenoid-activated check valve is in a deactivated state.

Assignees

• Ford Global Tech Llc

Inventors

• Pursifull Ross Dykstra
• Ulrey Joseph Norman
• Lawther Robin Ivo
• Zeng Paul

Classifications

• F02M59/102

  Mechanical drive, e.g. tappets or cams (F02M45/063 takes precedence) · CPC title

• F02D41/3845

  by controlling the flow into the common rail, e.g. the amount of fuel pumped · CPC title

• F02M59/367 Primary

  Pump inlet valves of the check valve type being open when actuated · CPC title

• F02M2200/09

  Fuel-injection apparatus having means for reducing noise · CPC title

• F02M2200/02

  Fuel-injection apparatus having means for reducing wear · CPC title