Common rail fuel system having pump-accumulator injectors

Patent metadata

Field	Value
Publication number	US-10830194-B2
Application number	US-201615288729-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 7, 2016
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

A fuel system is disclosed for use with an engine. The fuel system may have a common rail, a first type of fuel injector fluidly connected to the common rail, and a second type of fuel injector fluidly connected to the common rail. The second type of fuel injector may include a pumping portion having a bore formed therein, and a plunger reciprocatingly disposed in the bore. The second type of fuel injector may also include an accumulator portion fluidly connected to the common rail and configured to receive fuel pushed from the bore of the pumping portion by the plunger, a nozzle portion, and a valve portion fluidly connecting the pumping, nozzle, and accumulator portions.

First claim

What is claimed is:

1. A fuel system, comprising:
a common rail;
a first type of fuel injector fluidly connected to the common rail; and
a second type of fuel injector fluidly connected to the common rail,
wherein the first type of fuel injector does not have an internal pumping portion and is not configured to internally increase the pressure of fuel for fuel injection by the first type of fuel injector, and
wherein the second type of fuel injector includes:
a pumping portion having a bore formed therein;
a plunger reciprocatingly disposed in the bore;
an accumulator portion fluidly connected to the common rail and configured to receive fuel pushed from the bore of the pumping portion by the plunger;
a nozzle portion; and
a valve portion fluidly connecting the pumping, nozzle, and accumulator portions.

2. The fuel system of claim 1 , wherein the second type of fuel injector is configured to pump fuel into the common rail for injection by only the first type of fuel injector.

3. The fuel system of claim 2 , wherein the first type of fuel injector is configured to inject fuel received from only the common rail.

4. The fuel system of claim 3 , wherein the first type of fuel injector includes an accumulator portion fluidly connected to the common rail.

5. The fuel system of claim 2 , wherein:
the common rail is fluidly connected to a plurality of the first type of fuel injector and to a plurality of the second type of fuel injector; and
a number of the second type of fuel injectors fluidly connected to the common rail is less than a number of the first type of fuel injectors fluidly connected to the common rail.

6. The fuel system of claim 5 , wherein:
the number of the first type of fuel injectors is twice the number of the second type of fuel injectors;
each of the second type of fuel injectors is connected to the common rail between adjacent fuel injectors of the first type; and
terminal ends of the common rail are connected to the first type of fuel injectors.

7. The fuel system of claim 2 , wherein:
the common rail is fluidly connected to a plurality of the first type of fuel injector and to a plurality of the second type of fuel injector; and
a number of the second type of fuel injectors fluidly connected to the common rail is about equal to a number of the first type of fuel injectors fluidly connected to the common rail.

8. An internal combustion engine, comprising:
an engine block at least partially defining a plurality of cylinders;
a piston disposed within each of the plurality of cylinders;
at least one cylinder head configured to close off the plurality of cylinders and thereby form a plurality of combustion chambers;
a common rail;
a first type of fuel injector disposed at least partially within the at least one cylinder head and configured to inject fuel received from the common rail into a first of the plurality of combustion chambers, wherein the first type of fuel injector does not have an internal pumping portion and is not configured to internally increase the pressure of fuel for fuel injection by the first type of fuel injector; and
a second type of fuel injector disposed at least partially within the at least one cylinder head and configured to pump fuel into the common rail and to inject fuel into a second of the plurality of combustion chambers,
wherein:
each of the first and second types of fuel injectors include an accumulator portion configured to hold pressurized fuel for subsequent injection events; and
the second type of fuel injector further includes:
a pumping portion having a bore formed therein;
a plunger reciprocatingly disposed in the bore;
the accumulator portion fluidly connected to the common rail and configured to receive fuel pushed from the bore of the pumping portion by the plunger;
a nozzle portion; and
a valve portion fluidly connecting the pumping, nozzle, and accumulator portions.

Assignees

• Caterpillar Inc

Inventors

• Shafer Scott F
• Gibson Dennis H
• Li Zhenyu (Jason)
• Campion Robert Michael
• Stockner Alan Ray
• Pillarisetti Satya Naga Deepak
• Joseph George Kodikulam
• Wang Lifeng

Classifications

• F02M57/023

  mechanical · CPC title

• F02M63/0225 Primary

  Fuel-injection apparatus having a common rail feeding several injectors (F02M63/0003 takes precedence); Means for varying pressure in common rails; Pumps feeding common rails · CPC title

• F02M55/025

  Common rails · CPC title

• F02M63/0265

  Pumps feeding common rails · CPC title

• F02M63/0007

  using electrically actuated valves (injection valves F02M51/06) · CPC title