Information
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Patent Grant
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6629543
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Patent Number
6,629,543
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Date Filed
Friday, August 3, 200122 years ago
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Date Issued
Tuesday, October 7, 200320 years ago
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Inventors
-
Original Assignees
-
Examiners
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CPC
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US Classifications
Field of Search
US
- 137 508
- 137 510
- 137 12
- 123 457
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International Classifications
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Abstract
The present invention provides a fuel system for an internal combustion engine powered by fuel that includes a fuel tank having a wall defining a volume. The fuel system also includes a pump that is disposed proximate the fuel tank and operatively connected to the volume. The fuel system further includes piping that is coupled to the pump and is operatively connected to the internal combustion engine. A pressure regulator with a self-contained valve assembly is disposed in at least one of the pump or the piping.
Description
FIELD OF THE INVENTION
This invention relates to a fuel system for an internal combustion engine, and more particularly to a fuel system including a flow-through pressure regulator with a self-contained valve assembly for a vehicle powered by a fuel injected combustion engine.
BACKGROUND OF THE INVENTION
Most modern automotive vehicles are powered by an internal combustion engine that is connected with a source of fuel, e.g., gasoline, diesel, natural gas, alcohol, hydrogen, etc. The fuel is stored on-board the vehicle and supplied to the engine in a precisely controlled manner.
According to a conventional fuel system, gasoline is stored in a tank on-board a vehicle. The gasoline is withdrawn from the tank by a pump and fed through a filter to fuel injectors, which deliver the gasoline to combustion cylinders in the engine. The fuel injectors are mounted on a fuel rail to which fuel is supplied by the pump. The pressure at which the fuel is supplied to the fuel rail must be metered to ensure the proper operation of the fuel injectors. Metering is carried out by using pressure regulators which control the pressure of the fuel in the system at all engine r.p.m. levels.
It is believed that some existing pressure regulators employ a spring biased valve seat with a longitudinal flow passage. The valve seat is biased to a closed position at low fuel pressures. As fuel pressure builds in the system, the pressure against the valve seat overcomes the biasing force of the spring, allowing fuel to flow through the valve seat, thereby controlling the fuel pressure in the system.
In this type of pressure regulator, the valve seat and valve member were distinct components with various parts. The components are located at different positions within the housing of the pressure regulator and provide a valve assembly with distributed operative parts. These parts are believed to require detailed machining to fabricate. Thus, it is believed that a flow-through pressure regulator is needed that has a valve assembly that can be fabricated with fewer machined components, as well as with fewer components overall and that is configured within the pressure regulator so that the components are contained with a single operative part, i.e., self-contained.
SUMMARY OF THE INVENTION
The present invention provides a fuel system for an internal combustion engine powered by fuel that includes a fuel tank having a wall defining a volume. The fuel system also includes a pump that is disposed proximate the fuel tank and operatively connected to the volume. The fuel system further includes piping that is coupled to the pump and is operatively coupled to the internal combustion engine. A pressure regulator with a self-contained valve assembly is disposed in at least one of the pump or the piping.
The present invention also provides a method of supplying fuel tank to an internal combustion engine using a pump, a pressure regulator, and piping connecting the fuel tank, internal combustion engine, pump, and pressure regulator. The pressure regulator includes a self-contained valve assembly and an inlet and an outlet offset along an axis. The method is achieved by disposing the valve assembly with a closure member in a fluid flow path between the inlet and the outlet. The valve assembly defines the communication path between the inlet and the outlet. The method is also achieved by occluding flow between the inlet and outlet through the communication path of the valve assembly with the closure member when the valve assembly is in a first position at a first pressure and by permitting flow between the inlet and outlet through the communication path of the valve assembly when the valve assembly is in a second position at a second pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain the features of the invention.
FIG. 1
illustrates a fuel system according to the present invention.
FIG. 2
illustrates a flow-through regulator according to a preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1
illustrates a fuel system
1000
including a tank
1010
, a pump
1020
, a filter
1030
, a pressure regulator
1040
, a fuel rail
1050
, at least one fuel injector
1060
, and an internal combustion engine
1070
. These components are interconnected by piping as will be described in greater detail below.
The tank
1010
holds fuel. The pump
1020
is shown connected to an inside of the fuel tank
1010
. In other words, the pump
1020
can be secured to or retained to or supported by the inside of the fuel tank
1010
. However, the pump
1020
can also be connected on an exterior of the tank
1010
, or can be remotely connected with respect to the tank
1010
. The filter
1030
and the pressure regulator
1040
are shown connected inside the pump
1020
. However, the filter
1030
and the pressure regulator
1040
, either individually or an integral combination, can also be connected on the exterior of the pump
1020
, or can be connected remotely with respect to the pump
1020
. The tank
1010
, pump
1020
, filter
1030
, and pressure regulator
1040
can be coupled by piping such that the fuel
1012
can be filtered in the filter
1030
before entering the pump
1020
, or between the pump
1020
and the fuel rail
1050
. Coupling thus refers to any connection permitting fluid communication. The pressure regulator
1040
can be coupled to a tap in piping between the pump
1020
and the filter
1030
, or between the filter
1030
and the fuel rail
1050
. Fuel
1012
that is bled-off by the pressure regulator
1040
is returned to the pump
1020
. The fuel
1012
supplied to the fuel rail
1050
is supplied to each of the injector(s)
1060
, and subsequently supplied by the injector
1060
to the engine
1070
, e.g., into individual combustion cylinders of the engine
1070
.
FIG. 2
illustrates a flow-through pressure regulator
10
according to a preferred embodiment. The flow-through pressure regulator
10
includes a housing
20
. The housing
20
is separated by a valve assembly
30
into a first chamber
40
and a second chamber
50
. The valve assembly
30
has a passage
60
that communicates the first chamber
40
with the second chamber
50
. The valve assembly
30
permits or inhibits flow through the passage
60
. A filter
80
is disposed in the flow path of the housing
20
. The housing
20
has an inlet
202
and an outlet
204
offset along a longitudinal axis A. The housing
20
can include a first cup-shaped member
206
and a second cup-shaped member
208
that are crimped together to form a unitary housing
20
with a hollow interior
211
. Although the unitary housing
20
is formed by two joined members, it is to be understood that the unitary housing could be formed with multiple members integrated together, or alternatively, a monolithic member. Furthermore, while the preferred embodiment of the housing
20
includes cup-shaped members, the housing
20
can include other geometries as well, such as tubular-shaped members. The inlet
202
of the housing
20
is located in the first cup-shaped member
206
, and the outlet
204
of the housing
20
is located in the second cup-shaped member
208
. The inlet
202
can be a plurality of inlet apertures
210
located in the first cup-shaped member
206
. The outlet
204
can be a port
212
disposed in the second cup-shaped member
208
.
The first cup-shaped member
206
can include a first base
214
, a first lateral wall
218
extending in a first direction along the longitudinal axis A from the first base
214
, and a first flange
220
extending from the first lateral wall
218
in a direction substantially transverse to the longitudinal axis A. The second cup-shaped member
208
can include a second base
222
, a second lateral wall
224
extending in a second direction along the longitudinal axis A from the second base
222
, and a second flange
226
extending from the second lateral wall
224
in a direction substantially transverse to the longitudinal axis A. The valve assembly
30
includes a flexible divider
300
, which can be a diaphragm. The divider
300
is secured between the first flange
220
and the second flange
226
to separate the first chamber
40
and the second chamber
50
. The first flange
220
can be rolled over the circumferential edge of the second flange
226
and can be crimped to the second flange
226
to form the unitary housing
20
.
In addition to the divider
300
, the valve assembly
30
includes a tubular member
320
and a closure member
340
. The tubular member
320
is located in a central aperture
306
of the divider
300
to provide the passage
60
. The tubular member
320
includes a first tubular portion
322
and a second tubular portion
324
. The first tubular portion
322
is disposed entirely within the first chamber
40
and has a diameter disposed along the axis. An upper surface of the first tubular portion
322
extends substantially transverse to the longitudinal axis A and contacts a lower operative surface of the divider
300
. The first tubular portion
322
forms a chamber
326
housing the closure member
340
. The second tubular portion
324
is disposed substantially within the second chamber
50
and has a diameter disposed along the axis. The diameter of the second tubular portion
324
is smaller than the diameter of the first tubular portion
322
. An outer surface of the second tubular portion
324
is secured to a spring retainer
302
, preferably by an interference fit. The outer surface of the second tubular portion
324
, however, may be secured to the spring retainer
302
by staking or crimping. A lower end of the second tubular portion
324
extends beyond the divider
300
into the first chamber
40
and forms a unitary tubular junction
348
with an upper end of the first tubular portion
322
. The second tubular portion
324
includes a plurality of tubular apertures
325
located in an end proximate the outlet
204
to provide a flow path through the passage
60
.
The closure member
340
includes a ball
342
retained in a ball retainer
344
. The ball retainer
344
is disposed in the chamber
326
housing the closure member
340
and can be a flat annulus secured within chamber
326
by a flange provided at the lower end of the first tubular portion
322
. The flange of the lower end of the first tubular portion
322
allows for the ball retainer to move within the chamber
326
. This can be achieved by providing an aperture in the ball retainer
344
with an outside diameter which is smaller than an inner diameter of the first tubular portion
322
. The difference in diameters allows the ball retainer to move freely both axially and radially within the chamber
326
. The ball retainer
344
has a central aperture and a plurality of retainer apertures
346
located along a circumference of the ball retainer
344
. The central aperture of the ball retainer
344
is somewhat smaller than the diameter of the ball
342
and is finished to prevent a rough surface from contacting the ball
342
. The plurality of retainer apertures
346
in the ball retainer
344
permit flow through the first tubular portion
322
. An upper surface of the ball
342
seats on the tubular junction
348
. A lower surface of the ball
342
seats on a seating surface
230
formed in a center portion of the first base
214
along the longitudinal axis A and opposite the tubular junction
348
.
A first biasing element
330
, which can be a spring, is disposed within an inner diameter of the second tubular portion
324
, substantially within the second chamber
50
. An outer surface of the first biasing element
330
contacts an inner diameter of the second tubular portion
324
. The first biasing element
330
extends along the length of the second tubular portion
324
. An upper end of the first biasing element
330
engages the end of the second tubular portion
324
proximate the outlet
204
, while a lower end of the first biasing element
330
contacts the upper surface of the ball
342
. The first biasing element
330
biases the ball
342
at a predetermined force toward the base
214
.
A second biasing element
90
, which can be a spring, is disposed entirely within the second chamber
50
and is concentric with the first biasing element
330
. The second biasing element
90
engages a locator
228
on the base
222
of the second cup-shaped member
208
and biases the valve assembly
30
toward the base
214
of the first cup-shaped member
206
. The second biasing element
90
biases the valve assembly
30
at a predetermined force, which relates to the pressure desired for the regulator
10
. The base
222
of the second cup-shaped member
208
has a dimpled center portion that provides the outlet portion
212
in addition to the locator
228
. A first end of the second biasing element
90
is secured on the locator
228
, while a second end of the second biasing element
90
can be supported by the spring retainer
302
.
The operation of the flow-through pressure regulator
10
will now be described. It is to be understood that the following description can also explain the operation of the invention when utilized as a pressure-relief device. The second biasing element
90
acts through the spring retainer
302
to bias the divider
300
, and hence the valve assembly
70
, toward the base
214
of the first cup-shaped member
206
. The first biasing element
330
biases the ball
342
of the closure member
340
, against the seating surface
230
in the base
214
of the first cup-shaped member
206
. When the ball
342
is seated against the tubular junction
348
, the valve assembly
70
is in a closed position, and no fuel can pass through the regulator
10
.
Fuel enters the regulator
10
through inlet apertures
210
and exerts pressure on the valve assembly
70
, including the divider
300
. When the pressure of the fuel is greater than the force exerted by the second biasing element
90
, the valve assembly
70
is displaced along the longitudinal axis A toward the outlet
204
. The force exerted by the first biasing element
330
unseats the ball
342
from the tubular junction
348
creating a pathway for the fuel. Fuel enters the first tubular portion
322
around the ball
342
and through the plurality of retainer apertures
346
located in the ball retainer
344
. The fuel enters the passage
60
through the gap created by the unseated ball
342
and exits the passage
60
along and transverse to the longitudinal axis A through the plurality of tubular apertures
325
located in the end of the second tubular portion
324
proximate the outlet
204
.
As the fuel pressure is reduced, the force of the second biasing element
90
overcomes the fuel pressure and returns the tubular junction
348
to seated engagement with the ball
342
, thus closing the passage
60
. Operating in this manner, the regulator
10
is able to maintain constant fuel pressure in a fuel system.
While the invention has been disclosed with reference to certain preferred embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the sphere and scope of the invention, as defined in the appended claims and their equivalents thereof. Accordingly, it is intended that the invention not be limited to the described embodiments, but that it have the full scope defined by the language of the following claims.
Claims
- 1. A fuel system for an internal combustion engine powered by fuel, comprising:a fuel tank having a wall defining a volume; a pump disposed proximate the fuel tank and operatively connected to the volume; piping coupled to the pump and operatively coupled to the internal combustion engine; and a pressure regulator with a self-contained valve assembly that carries a closure member and disposed in at least one of the pump or piping, the valve assembly having a first biasing element that biases the closure member in a direction that permits fuel flow through the pressure regulator.
- 2. The fuel system of claim 1, wherein the pressure regulator is disposed within the volume.
- 3. The fuel system of claim 1, wherein the pressure regulator is connected to an interior surface of the wall.
- 4. The fuel system of claim 1, wherein the pressure regulator is coupled to the pump.
- 5. The fuel system of claim 1, wherein the pressure regulator is disposed outside the volume.
- 6. The fuel system of claim 1, wherein the pressure regulator is connected to an exterior surface of the wall.
- 7. The fuel system of claim 1, further comprising:a filter adapted for filtering the fuel, the filter being interposed in fluid communication along the piping, and adapted to be interposed between the tank and the internal combustion engine.
- 8. The fuel system of claim 7, wherein the pressure regulator is in fluid communication along the piping, and adapted to be interposed between the pump and the filter.
- 9. The fuel system of claim 7, wherein the pressure regulator is in fluid communication along the piping, and adapted to be interposed between the filter and the internal combustion engine.
- 10. The fuel system of claim 1, wherein the pressure regulator includes:a housing having an inlet and an outlet offset along an axis; and the valve assembly being disposed between the inlet and outlet along the axis separating the housing into a first chamber and a second chamber, the valve assembly being positional in a first position that inhibits flow between the first chamber and the second chamber through the valve assembly.
- 11. The fuel system of claim 10, wherein the valve assembly comprises a flexible divider having a first operative surface and a second operative surface, the first operative surface being exposed to the first chamber, the second operative surface being exposed to the second chamber, a tubular member coupled to the first surface and the second surface, the tubular member having a passage along the axis that communicates the first chamber with the second chamber, when the valve assembly is in the second position.
- 12. The fuel system of claim 10, wherein the tubular member comprises a first tubular portion and a second tubular portion, the first tubular portion having a major diameter disposed along the axis and the second tubular portion having a minor diameter disposed along the axis.
- 13. The fuel system of claim 12, wherein the first tubular portion is disposed in the first chamber and the second tubular portion is disposed substantially in the second chamber.
- 14. The fuel system of claim 13, wherein a lower end of the second tubular portion extends from the second chamber, through the divider and into the first chamber, the lower end of the second tubular portion and an upper end of the first tubular portion forming a tubular junction.
- 15. The fuel system of claim 14, wherein the first biasing element is disposed within the second tubular portion, biases the closure member toward the inlet, and a second biasing element, disposed in the second chamber and concentric with the first biasing element, biases the valve assembly toward the inlet.
- 16. The fuel system of claim 15, wherein an outer surface of the second tubular portion is secured by interference to a retaining element.
- 17. The fuel system of claim 16, wherein the valve seat comprises a first surface disposed along the axis in the first chamber and a second surface disposed along the axis in the first chamber.
- 18. The fuel system of claim 17, wherein the first surface of the valve seat includes the tubular junction and the second surface of the valve seat includes a portion of the housing.
- 19. The fuel system of claim 18, wherein the closure member comprises a spherical portion disposed in a retainer, the retainer being coupled to the first tubular portion.
- 20. The fuel system of claim 19, wherein the housing comprises a first cup-shaped member and a second cup-shaped member, the first cup-shaped member having a first base, a first lateral wall extending in a first direction along the axis from the first base, and a first flange extending from the first lateral wall in a direction substantially transverse to the axis, the second cup-shaped member having a second base, a second lateral wall extending in a second direction along the axis from the second base, and a second flange extending from the second lateral wall in a direction substantially transverse to the axis, the first flange and the second flange being secured together to provide a unitary housing.
- 21. The fuel system of claim 20, wherein the second surface of the valve seat includes a portion of the first base having a configuration complementary to the closure member.
- 22. The fuel system of claim 21, wherein the valve assembly is secured between the first flange and the second flange.
- 23. A method of supplying fuel from a fuel tank to an internal combustion engine using a pump, a pressure regulator, and piping connecting the fuel tank, internal combustion engine, pump, and pressure regulator, the pressure regulator having a self-contained valve assembly and including an inlet and an outlet offset along an axis, the method comprising:disposing the valve assembly with a closure member in a fluid flow path between the inlet and the outlet, the valve assembly defining the communication path between the inlet and the outlet; occluding flow between the inlet and outlet through the communication path of the valve assembly with the closure member, the valve assembly being in a first position at a first pressure; and permitting flow between the inlet and the outlet through the communication path of the valve assembly via a first biasing element that biases the closure member away from a seat of the valve assembly, the valve assembly being in a second position at a second pressure less than a first pressure to regulate a pressure of the fuel being supplied to the engine.
- 24. The method of claim 23, further comprising:providing the valve assembly with a flexible divider, the divider being substantially transverse to the axis; providing the divider with a first operative surface and a second operative surface; suspending a tubular member by the divider; providing the tubular member with a passage along the axis that communicates the first chamber with the second chamber; and providing the valve assembly with a valve seat.
- 25. The method of claim 24, wherein the tubular member comprises a first tubular portion and a second tubular portion, the first tubular portion having a major diameter disposed along the axis and the second tubular portion having a minor diameter disposed along the axis.
- 26. The method of claim 25, further comprising:disposing the first tubular portion entirely in the first chamber; disposing the second tubular portion substantially in the second chamber, a lower end of the second tubular portion extending past the divider; forming a tubular junction with the lower end of the second tubular portion and an upper end of the first tubular portion; disposing a first biasing element within the second tubular portion, the first biasing element biasing the closure member toward the inlet; and disposing a second biasing element in the second chamber and concentric with the first biasing element, the second biasing element biasing the valve assembly toward the inlet.
- 27. The method of claim 26, wherein the valve seat comprises a first surface disposed along the axis in the first chamber and the second surface disposed along the axis in the first chamber, the first surface including the tubular junction and the second surface including a portion of the housing adapted to support a surface of the closure member.
- 28. The method of claim 27, further comprising:disposing a spherical portion of the closure member in a retainer; and coupling the retainer to the first tubular portion.
- 29. The method of claim 28, wherein the housing comprises a first cup-shaped member and a second cup-shaped member, the first cup-shaped member having a first base, a first lateral wall extending in a first direction along the axis from the first base, and a first flange extending from the first lateral wall in a direction substantially transverse to the axis, the second cup-shaped member having a second base, a second lateral wall extending in a second direction along the axis from the second base, and a second flange extending from the second lateral wall in a direction substantially transverse to the axis, the first flange and the second flange being secured together to provide a unitary housing.
US Referenced Citations (14)