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Claims  |
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What is claimed is:
1. A two-stage fuel pump utilizing a single rotor which comprises:
(a) a base housing having an inlet in communication with an inlet of an
annular lateral channel in a first radius, a swirl chamber located
centrally of said housing and spaced inwardly from said first radius and
within a second radius, a lateral channel outlet in communication with
said swirl chamber, and a regenerative sweep channel outside said first
radius and within said housing, said swirl chamber having an outlet in
communication with said sweep channel, said sweep channel having an outlet
for fuel under pressure, and
(b) a single rotor in said base housing having a first series of
circumferentially spaced blades to operate in said sweep channel, a second
series of blades forming axial openings at the first radius to rotate
adjacent said lateral channel, and a third series of blades forming axial
openings in the area of said swirl chamber to pass fuel from said lateral
channel to said swirl chamber.
2. A two stage fuel pump as defined in claim 1 in which the outlet from
said swirl chamber comprises a tangential passage terminating at said
sweep channel.
3. A two stage fuel pump as defined in claim 1 in which said swirl chamber
has a central base opening to allow vapor to escape said base housing.
4. A two stage fuel pump as defined in claim 1 in which said swirl chamber
tapers toward the bottom of said base housing and a central opening at the
bottom of said swirl chamber is provided to allow vapor to escape said
base housing.
5. A two stage fuel pump as defined in claim 1 in which a lateral channel
outlet chamber is formed above said rotor in communication with said
lateral chamber outlet and positioned above said swirl chamber and above
said third series of blades, and the axial openings formed by said third
series of blades registering with said swirl chamber.
6. A two stage fuel pump for feeding fuel from a supply tank to an internal
combustion engine which comprises:
(a) a fuel pump having a drive armature with a drive shaft and outlet
housing associated with a pump outlet,
(b) a base assembly including a bottom housing having an inlet passage, a
bottom central swirl chamber, and an outlet passage for a primary pump,
(c) a top housing on said base assembly with an annular lateral channel
formed therein and a top central chamber in communication with said
lateral channel,
(d) a first and second stage single rotor associated with and to be driven
by said drive shaft and interposed between said bottom housing and said
top housing, said rotor having a first stage pump comprised of a series of
circumferentially disposed axial openings and vanes radially registering
with said lateral channel, a second series of circumferentially disposed
axial openings and vanes radially registering with said central chamber in
said top housing and said bottom swirl chamber in said base assembly, and
a series of regenerative pump blades in the periphery of said rotor to
form a second stage pump, and
(e) said outlet for said primary pump extending from said swirl chamber to
an inlet to the regenerative pump in a sweep passage coincident with said
peripheral blades. |
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Claims  |
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Description  |
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FIELD OF THE INVENTION
Vehicle fuel pumps for internal combustion engines using a first stage
lateral side channel pump to supply a high pressure turbine regenerative
pump.
BACKGROUND OF THE INVENTION
Lateral side channel fuel pumps are know, as illustrated in U.S. patent to
Scheinfurther No. 4,408,952 issued Oct. 11, 1983. Regenerative turbine
type fuel pumps are known as illustrated in U.S. Pat. No. 4,556,363 to
Watanabe et al, issued Dec. 3, 1985. Two stage fuel pumps combining a
lateral side channel pump as a first stage and a regenerative turbine pump
as a second stage are known, as illustrated in British Patent GB 2,134,598
published Aug. 15, 1984 and in a U.S. Pat. No. 4,408,952 to Schweinfurter.
A pump with a lateral side channel as a first stage and a positive
displacement gear rotor as a second stage is disclosed in U.S. Pat. No.
5,149,252 issued Sep. 22, 1992 by Charles H. Tuckey and assigned to the
assignee of the present application.
Two stage pumps utilizing a single rotor are illustrated in the above
referenced British Patent 2,134,598 and U.S. Pat. 4,408,952, and the
concept of vapor release, sometimes referred to as de-gassing is disclosed
also in these patents as well as in U.S. Pat. No. 4,149,252.
Thus, two stage fuel pumps utilizing a single rotor, combining a lateral
side channel pump and a regenerative turbine pump, and also incorporating
vapor release, are illustrated in the above referenced patents. The
present invention is directed to a two stage pump with a lateral side
channel and a regenerative turbine with a single rotor and a housing which
is designed to effectively increase vapor separation and release as well
as the efficiency of the combined pumping stages.
SUMMARY OF THE INVENTION
The pump has a rotor operating in a sealed housing with an inlet at one end
and an outlet at the other end. The rotor has three operating areas. At
the outer periphery, there are vanes operating in an annular sweep channel
as a second stage regenerative pump which produces the desired high
pressure and directs liquid fuel to the pump chamber and outlet. Radially
within the periphery are two radially spaced series of blades forming
axial passages in said rotor, the first and outer series of blades operate
under an annular lateral channel passage to form a first stage fuel pump
delivering fuel to a central swirl chamber above and below the rotor. The
second and inner series of blades and axial passages allow fuel to pass
through the rotor to said lower swirl chamber. The lower swirl chamber has
a central bottom outlet for vapor and a tangential fuel outlet directed to
the inlet of the second stage high pressure pump.
Objects, features and advantages of the present invention are to provide a
two stage pump with a unique single rotor which serves as a lateral first
stage, and a turbine regenerative second stage and also operates in
opposed central recesses to control vapor flow as well as feed liquid fuel
to the second stage pump, substantially improved vapor separation,
increased efficiency, and is of economical manufacture and assembly and
has a long useful life in service.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of this invention will be
apparent from the following detailed description of the preferred
embodiment (s) and best mode, appended claims, and accompanying drawings
in which:
FIG. 1 is a full sectional view of a vehicle fuel pump embodying this
invention.
FIG. 2 is a plan view of a base part of the pump below the operating rotor
taken on line 2--2 of FIG. 1.
FIG. 3 is a plan view of a face plate below the operating rotor and taken
on line 3--3 of FIG. 1.
FIG. 4 is a partial sectional taken on line 4--4 of FIG. 3.
FIG. 5 is a plan view of the stationary outer ring surrounding the rotor
taken on line 5--5 of FIG. 1.
FIG. 6 is a section of the ring illustrated in FIG. 5 taken on line 6--6 of
FIG. 5.
FIG. 7 is a plan view of the pump rotor.
FIG. 8 is a fragmental side view of the edge of the rotor taken on line
8--8 of FIG. 7.
FIG. 9 is a perspective view of the rotor illustrated in FIG. 7.
FIG. 10 is a top view of an upper face plate located above the operating
pump rotor.
FIG. 11 is a sectional view taken on line 11--11 of FIG. 10.
FIG. 12 is a sectional view taken on line 12--12 of FIG. 10.
FIG. 13 is a mirror image of the bottom of the upper face plate illustrated
in FIGS. 10, 11 and 12 oriented to conform to the orientation of FIGS. 2,
3, 5 and 10.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the drawings, FIG. 1 is a full section of a fuel pump
embodying this invention with some of the passages of the components
rotated into the plane of the section for purposes of illustration. The
actual component parts shown in FIGS. 2 to 13 vary somewhat from the
sectional view in FIG. 1. An inlet housing 20 is positioned at one end and
an outlet housing 22 is located at the other end of the pump. The outlet
housing has a fuel outlet pipe 24 and carries brushes 26, 28 provided for
the rotating armature 30 which is surrounded by permanent magnets 32 and a
flux ring 34 of an electric drive motor. The operating parts are encased
in a metallic shell 36 spun around O-rings 38 at each end. A pump of this
general nature is illustrated and described in U.S. Pat. No. 4,540,354
issued Sep. 10, 1985 to Charles H. Tuckey and assigned to the assignee of
the present application.
With particular reference to the present invention, the basic parts of the
pump include the inlet housing 20, a lower face plate 40, a rotor ring 42,
a rotor 50, and an upper face plate 52. The inlet housing 20 forms a base
plate for the pump and has a fuel inlet opening 60 ensmalling to a
vertical passage 62. Centrally of the housing 20 is a vapor separation
chamber 64 (FIG. 2) which has a tangential outlet 66. The chamber 64
tapers to a bottom wall 68 which has a vapor outlet 70. An orientation
notch 72 is provided to assist in circumferential alignment of the parts
in assembly.
Above the inlet housing 20 is the lower face plate 40 shown in a plan view
in FIG. 3. This face plate lies below the rotor 50 and has an annular
pumping sweep channel 80 originating at a through passage 82 which aligns
with the tangential passage 66 of the inlet housing 20. A passage 84 of
FIG. 3 aligns with the fuel inlet passage 62 of FIG. 2 . It will be seen
that when the lower face plate 40 of FIG. 3 is over laid on the housing 20
of FIG. 2, the passage 82 is aligned with passage 66 of FIG. 2. Centrally
of the plate 40 is a circular opening 86 which registers with the chamber
64 of the inlet housing 20. An opening 88, shown in FIG. 3, is the
termination of the annular pumping sweep channel 80 and forms an inlet
port for the second and high pressure stage pump. Rotation of the rotor 50
is counter clockwise as viewed in FIG. 3.
Above the lower face plate 40 is the rotor ring 42 which is shown in plan
view in FIG. 5 and in section in FIG. 6. This ring has an annular inner
rib 90 which tapers toward each side of the ring and extends about
240.degree. around the ring. A notch 92 registers with the inlet port 82
(FIG. 3) of the high pressure pump and a notch 93 registers with the
outlet port 88 (FIG. 3). When ring 42 is overlaid on the lower face plate
40 (FIG. 3), the notch 92 will register with the port 82 and the notch 93
will register with port 88.
Above the face plate 40, and cooperating with the rotor ring 42, is the
pump rotor 50 shown in plan view in FIG. 7, in partial side view in FIG. 8
and in perspective in FIG. 9. This rotor 50 is driven by the armature
shaft 100 passing through a center hole in the rotor. The rotor has
staggered blades forming pockets 102 on one side and pockets 104 on the
other side to form a regenerative turbine type pump of the same type as
shown and described in U.S. Pat. Nos. 5,257,916 (Nov. 2, 1993) and
5,265,997 (Nov. 30, 1993) issued to Charles H. Tuckey and assigned to the
assignee of the present application.
The rotor 50, however, is distinguished from previous rotors in having two
radially spaced series of axial openings inside the toothed periphery. The
first series of sixteen spaced trapezoidal openings 110 with intervening
blades 111 are located within the periphery. As shown in FIG. 1, these
openings 110 register with the inlet passage 62 and 84. The second series
of six essentially triangular openings 120 and intervening blades 121 are
around the central drive shaft 100. These openings 120 overlie the central
opening 86 in the lower face plate 40.
The upper face plate 52 is positioned above the rotor 50 and is shown in
FIGS. 10-13. The view in FIG. 13 is a mirror immage of the bottom surface
of plate 52 which faces the rotor 50 oriented to conform to FIGS. 2, 3 and
10. The face plate 52 has a central opening 130 which houses a bearing 132
for the armature shaft 100. An annular top groove 134 receives the lower
end of the flux ring 34. An annular lateral side channel 136 (FIGS. 11-13)
is radially positioned above the openings 110 of the rotor 50 (FIG. 1) and
accompanying blades 111 between the openings. Also, an annular sweep
channel 140 (FIGS. 11-13) is positioned above the regenerative blades
102,104 (FIG. 1) as a part of the high pressure second stage pump
channels. In FIG. 12 a high pressure outlet channel 142 opens from the
regenerative pump sweep channel 140 to the armature chamber and passes
pump outlet fuel to the outlet pipe 24. In the bottom surface of the plate
52 is a control chamber 144 which lies above the rotor openings 120 (FIG.
1) and the blades 121 which separate them, and also is directly above the
opening 86 in lower plate 40 and the chamber 64 in the inlet housing 20.
When the upper plate 52 is overlaid on the rotor it will be seen that its
register notch 72 matches that of the ring 42, lower plate 40 and housing
20. As shown in FIG. 13, when the bottom of plate 52 is placed on rotor 50
with its notch 72 aligned, the high pressure outlet 142 also registers
with the lower plate outlet passage 88 and the notch 93 in ring 42 (FIG.
5). The outlet 142 is shown on the left side in FIG. 1, for convenience in
the explanation of the operation, but in the actual upper plate 52, as
viewed in FIGS. 10, 12 & 13, the pump outlet 142 is on the right side.
The entry of fuel is at 150 in the upper sweep channel 140 of the
regenerative pump (FIG. 13) and the rotation of the rotor is counter
clockwise in the channel 140 to the high pressure outlet 142.
IN THE OPERATION
The operation of the two stage pump is described in reference to FIG. 1
although it will be appreciated that the location of the actual
components, as above described, vary to a degree from those shown in FIG.
1.
The inlet 60 of the pump will be disposed in liquid fuel in a fuel tank or
fuel reservoir with appropriate filters. Upon operation of the electric
motor and rotor 50, fuel will be drawn up into the passages 62, 84 through
the openings 110 between the blades 111 in the rotor to the lateral
channel 136 (FIGS. 11-13) of the first pump stage where it will move
circumferentially and enter the chamber 144 in housing 52. The swirling
fuel will then pass down through the openings 120 in the rotor to the
swirl chambers 86 and 64 and receive further rotary impetus as it passes
between the moving blades 121 of the rotor. The chamber 64 narrows at the
bottom and opens to the tangential outlet 66 (FIGS. 1 and 2). The heavier
liquid fuel which is swirling in chamber 64 will move to the outside of
the chamber and to outlet 66, while the lighter vaporized fuel will
accumulate at the center. This vaporized fuel can exit through the bottom
central port 70 while the liquid fuel passes through the tangential
passage 66 up through passage 82 in the lower plate 40 and up to the
periphery of the regenerative second stage pump where it will enter at 82
(FIGS. 3 and 4) into the lower sweep channel 80 also shown in FIG. 3 and
the corresponding upper sweep channel 140 in the upper plate 52 (FIGS. 11,
12 and 13). The fuel in the secondary high pressure regenerative pump
moves through the channels 80 and 140 counter clockwise, gaining in
pressure, until it exits at passages 88 & 93 into outlet port 142 shown
diagrammatically in FIG. 1 and actually in FIGS. 10, 12 and 13. This high
pressure fuel enters the armature chamber of the pump and reaches the pump
outlet 24 from which it will be delivered to the vehicle engine.
Thus, the fuel from the pump inlet 60 passes upward through the openings
110 in the rotor in upward travel to chamber 144 and then moves downward
from chamber 144 through openings 120 in the rotor to the swirl chamber
86, 64, and tangentially outward to the passage 66 and to the inlet of the
sweep channels 80, 140 of the second stage, high pressure pump. Meanwhile,
vapor is centrifigally separated from the liquid fuel in the swirl
chamber, collects centrally of the chamber 64 and exits through port 70.
* * * * *
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Description  |
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