Information
-
Patent Grant
-
6269799
-
Patent Number
6,269,799
-
Date Filed
Thursday, August 26, 199924 years ago
-
Date Issued
Tuesday, August 7, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Yuen; Henry C.
- Gimie; Mahmoud
Agents
- Knobbe, Martens, Olson & Bear, LLP
-
CPC
-
US Classifications
Field of Search
US
- 123 508
- 123 509
- 123 516
- 123 579
- 123 580
- 123 495
- 123 195 P
- 440 88
- 440 89
-
International Classifications
-
Abstract
A fuel supply system for use with an engine having four vertically-arranged cylinders and multiple charge formers prevents air or vapor pockets from accumulating within the fuel pump or fuel lines. A pair of fuel pumps are mounted vertically one above the other. A fuel inlet port of each pump is formed at the lower-most portion of the pump. A fuel discharge port is formed at the upper-most portion of each port. A conduit attached to the top fuel pump's discharge port supplies fuel to an uppermost and lowermost carburetor. A conduit from the lowermost fuel pump supplies fuel to the middle two carburetors. The uppermost carburetor's fuel inlet port is positioned vertically higher than the top fuel pump's discharge port. The second carburetor's fuel inlet port is positioned vertically higher than the second fuel pump's discharge port. Air or vapor pockets within the fuel lines naturally migrates through the fuel pump and through the fuel conduits into the carburetors without becoming trapped in the fuel supply system.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a fuel supply system for an engine, and more particularly to an improved fuel supply system for an engine having multiple charge formers.
2. Description of the Related Art
Many internal combustion engines are provided with a plurality of charge formers. With such an arrangement, it is desirable to ensure that the fuel supply system delivers fuel uniformly and equally to all of the charge formers. Although this is generally not a problem, with certain types of applications for internal combustion engines, it can become a problem.
For example, with some applications for internal combustion engines, the charge formers are disposed so that they are positioned vertically above each other. This is typical, for example, in outboard motor practice. In outboard motors, the engine is disposed so that its output shaft rotates about a vertically extending axis. As a result, the individual cylinders extend generally horizontally and are arranged in a vertically spaced relationship. The charge formers, therefore, adopt a similar attitude and disposition.
Fuel supply systems for engines with vertically-arranged charge formers frequently include a single conduit or manifold that extends from the fuel pump to all charge formers. The conduit may be configured in such a way that it forms areas where fuel or vapor can become trapped. Additionally, the fuel pump itself may be configured in such a way that it forms areas where fuel vapor can be trapped. If a fuel vapor pocket forms, then the charge formers downstream of the vapor pocket will not receive fuel, or at least not receive a desired amount of fuel, thereby affecting proper engine operation.
In an attempt to alleviate these problems, it has been proposed to provide the fuel pump at a lower location than the charge formers. Also, the fuel pump may be provided with a plurality of fuel outlets and conduits that feed respective carburetors of the system. With this type of arrangement, however, the fuel pump is normally positioned below the lowest carburetor. In this position, the relatively high head between the fuel pump and the highest carburetor restricts the fuel pump's ability to deliver fuel. Also, vapor venting is not assured. Furthermore, a fuel pump mounted below the lowest carburetor may not be capable of being powered by an engine camshaft.
Accordingly, a need exists for a fuel supply system for an engine having multiple charge formers, wherein the system ensures against vapor blockage in fuel supply lines. There is a further need for a fuel system having a fuel pump which is powered by a camshaft, the fuel pump being arranged to prevent vapor interference with fuel flow.
SUMMARY OF THE INVENTION
One aspect of the present invention involves an internal combustion engine having at least one variable volume combustion chamber. The combustion chamber is defined by at least a pair of components that move relative to each other. A charge former supplies a fuel/air charge to the combustion chamber, and a fuel supply system provides fuel to the charge former. The fuel supply system includes a fuel pump having a discharge port communicating through a conduit with the charge former. The discharge port is positioned at an uppermost portion of the fuel pump, and a discharge check valve is positioned adjacent the discharge port. This orientation of the fuel pump inhibits vapor from becoming trapped within the fuel pump.
Further aspects, features and advantages of the present invention will become apparent from the detailed description of the preferred embodiment which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features of the invention will now be described with reference to the drawings of a preferred embodiment of the present engine and fuel supply system. The illustrated embodiment is intended to illustrate but not limit the invention. The drawings contain the following figures:
FIG. 1
is a side elevational view of an outboard motor in which the present fuel supply system can be employed.
FIG. 2
is a top view of the outboard motor of
FIG. 1
, illustrating the engine and the fuel supply system, which is configured in accordance with a preferred embodiment of the present invention, with the cowling and selected components of the engine shown in phantom.
FIG. 3
is a side view of the outboard motor of
FIG. 1
with the cowling shown in section.
FIG. 4A
is a rear end view of the power head of the outboard motor of
FIG. 1
with the cowling shown in section.
FIG. 4B
is an enlarged, sectional view of a fuel pump of the fuel supply system shown in
FIGS. 2 and 4A
.
FIG. 5
is a view of a bank of carburetors and a portion of the fuel supply system of
FIG. 2
as viewed in the direction of line
5
—
5
of
FIG. 2
, with the fuel delivery lines unattached to the engine.
FIG. 6A
is a side cross-sectional view of one of the carburetors of the engine taken along lines
6
A—
6
A of FIG.
2
.
FIG. 6B
is a cross-sectional view of one of the carburetors taken along lines
6
B—
6
B of FIG.
5
.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1
illustrates an outboard drive
10
which incorporates a fuel supply system configured in accordance with the preferred embodiment of the present invention. Because the present fuel supply system has particular utility with an outboard motor, the fuel supply system is described below in connection with the outboard motor. However, the description of the invention in conjunction with the illustrated outboard motor is merely exemplary.
The outboard motor
10
has a power head
12
which includes an internal combustion engine
14
. A protective cowling assembly
16
surrounds the engine
14
. The cowling assembly
16
includes a lower tray
16
a
and a main cowling member
16
b.
As is typical with outboard motor practice, the engine
14
is supported within the power head
12
so that its output shaft
17
(i.e., a crankshaft as illustrated in
FIG. 2
) rotates about a vertical axis. The crankshaft
17
is coupled to a drive shaft
19
that depends through and is journalled within a drive shaft housing
18
.
The drive shaft housing
18
extends downward from the cowling
16
and terminates in a lower unit
20
. The drive shaft
19
extends into the lower unit
20
to drive a transmission housed within the lower unit
20
. The transmission selectively establishes a driving condition of a propulsion device
22
. In the illustrated embodiment, the propulsion device
22
is a propeller. The transmission desirably is a forward/neutral/reverse-type transmission so as to drive the watercraft in any of these operational states.
A steering shaft extends through a steering bracket
24
and rotates about a vertically extending axis. The steering bracket
24
is affixed to the drive shaft housing
18
by upper and lower brackets
26
,
28
. Steering movement occurs about a generally vertical steering axis which extends through the steering shaft. A steering arm
30
is connected to an upper end of the steering shaft
26
and extends in a forward direction for manual steering of the outboard motor
10
, as known in the art.
The swivel bracket
26
also is pivotally connected to a clamping bracket
32
by a pin
34
. The clamping bracket
32
, in turn, includes a transmission adapted to attach to a transom
36
of an associated watercraft
37
. The clamping bracket
32
is arranged on the transom
36
at a location which supports the outboard motor
10
in a generally upright position and at a location where the blades of the propeller
22
lie at least partially beneath the surface level S of the body of water in which the watercraft
37
is operated.
The conventional coupling between the swivel bracket
26
and the clamping bracket
32
permits adjustment of the trim position of the outboard motor
10
, as well as allows the outboard motor
10
to be tilted up for transportation or storage. For this purpose, a conventional tilt and trim cylinder assembly desirably operates between the clamping bracket
32
and the swivel bracket
26
. This conventional mounting thus permits the outboard motor
10
to move within a normal or designed range of positions relative to the transom between a generally upright position (or slightly tilted away from the transom) to a full tilt-up position. This results in about an 80 degree range of movement when installed on the transom (i.e., between normal operating positions).
The drive shaft
19
drives a water pump which preferably is disposed at the lower end of the drive shaft housing
18
. The pump draws water through an inlet port
35
and delivers the water to the engine
14
. At least a portion of the cooling water is discharged from the outboard motor
10
through an exhaust system (described later) with the exhaust gasses from the engine in order to cool and silence the exhaust gasses, as known in the art.
The construction of the outboard motor
10
as thus far described is considered to be conventional, and for that reason further details of the construction are not believed necessary to permit those skilled in the art to understand and practice the invention.
In order to facilitate the description of the present invention, the terms “front” and “rear” or “aft” are used to indicate the relative sides of the components of the engine and the fuel supply system. As used herein, “front” refers to the side closest to the transom
36
, while “rear” or “aft” refer to the side farthest from the transom
36
.
With reference to
FIGS. 2 and 3
, the engine
14
preferably operates on a four-cycle combustion principle and includes a cylinder block
38
having four cylinders
40
formed therein in a vertically spaced arrangement.
FIG. 2
illustrates a top cylinder
40
in phantom lines. A piston
42
is positioned within the cylinder
40
and is adapted for reciprocating movement therein. The piston
42
is connected to a first end of a connecting rod
44
. A second end of the rod
44
is rotatably connected to a throw of the crankshaft
17
. The crankshaft
17
rotates about a substantially vertical axis and is enclosed within a crankcase
46
, which in the illustrated embodiment is formed between an aft end of the cylinder block
38
and a crankcase member
48
.
A cylinder head
50
is attached to the cylinder block
38
. A combustion chamber is formed by the cylinder head
50
, and corresponding cylinder
40
and piston
42
. An intake port
52
is formed through the cylinder head
50
, providing a passageway for an air/fuel charge to enter the combustion chamber. An intake valve
54
is supported by the cylinder head
50
and is adapted to regulate flow through the intake port
52
into the combustion chamber. An intake valve camshaft
56
is journalled within the cylinder head
50
. The intake valve camshaft
56
actuates the intake valve
54
in a reciprocating manner as known in the art. Each cylinder of the engine has associated with it an intake port and intake valve which is actuated by the camshaft.
An exhaust port
58
is also formed in the cylinder head
50
. The exhaust port
58
provides a passage for exhausts product to exit the combustion chamber. An exhaust valve
60
is supported by the cylinder head
50
and regulates flow through the exhaust port
58
. An exhaust valve camshaft
62
is journalled within the cylinder head
50
and is adapted to actuate the exhaust valve
60
in a reciprocating manner similar to that of the intake valve and intake valve camshaft. Again, each cylinder of the engine has associated with it an exhaust port and an exhaust valve which is actuated by the corresponding camshaft. While the illustrated embodiment employs one intake valve and one exhaust valve per cylinder, other numbers of exhaust and intake valves can also be used.
A cylinder cover
64
is fit over the cylinder head
50
and encloses a camshaft chamber
66
therein. The camshafts
56
,
62
and valves
54
,
60
are enclosed within the camshaft chamber
66
.
A drive pulley
68
is connected to the crankshaft
17
. A pair of camshaft driven pulleys
70
are also provided and are connected to respective camshafts
56
,
62
. A belt
72
extends around the pulleys
68
,
70
. In this manner, the drive pulley
68
drives the camshaft pulleys
70
. To ensure proper valve timing, the camshaft drive pulleys are preferably twice the diameter of the crankshaft drive pulley.
As best shown in
FIG. 3
, a flywheel
74
is positioned above the crankshaft drive pulley
68
and is adapted to rotate with the crankshaft
17
. It is to be understood that although the flywheel
74
and the pulleys
68
,
70
are illustrated as disposed at the top of the engine, these components can be appropriately rearranged. For example, the drive shaft and flywheel may be positioned at the bottom of the engine.
An air inlet device
76
is positioned near the front of the engine
14
and is adapted to intake air from within the cowling
16
. As best shown in
FIG. 3
, the air inlet device
76
splits into four intake pipes
78
, each intake pipe
78
being adapted to deliver an air charge to a corresponding combustion chamber. A carburetor
80
communicates with an each intake pipe opposite of the intake device
76
and is adapted to introduce a fuel charge into the air charge. Each of the carburetors
80
are connected to an intake manifold
82
. The intake manifold
82
includes a plurality of passages
84
. The manifold passages
84
communicate with the intake ports
52
formed in the cylinder head
50
. For each cylinder, the air/fuel charge is delivered from the corresponding intake passage
84
to the intake port
52
, as regulated by the intake valve
54
, to the corresponding combustion chamber. After combustion, the exhaust products flow through the exhaust valve
60
, out of the exhaust port
58
, and to an exhaust manifold
86
.
With reference also to
FIG. 4A
, an oil fill port
88
is located on the cylinder head cover
64
. The fill port
88
extends through the cylinder head cover
64
, allowing addition of lubricant into the camshaft chamber
66
. Oil galleries are formed in the cylinder block
38
and are adapted to communicate lubricant from the camshaft chamber
66
to various engine components, such as the pistons
42
, crankshaft
17
and connecting rods
44
. An oil pan (not shown) desirably collects oil that has circulated through the galleries and the crankcase
66
. In one mode, the oil pan can be mounted to an underside of an exhaust guide
90
(which is shown in FIG.
3
).
As seen in
FIG. 2
, an oil pump
90
is provided for transferring oil from the oil pan to the camshaft chamber
66
and for recirculation through the engine. An oil conduit
92
communicates lubricant from the oil pump
90
to the camshaft chamber
66
.
A blow-by gas vapor separator
94
is mounted on the cylinder head cover
64
and communicates with the camshaft chamber
66
. A return pipe
96
extends from the vapor separator
94
to the air inlet device
76
. Blow-by gasses separated from oil within the vapor separator
94
are delivered through the return pipe to the air inlet device
76
for eventual delivery to one of the combustion chambers for burning.
A pair of fuel pumps
98
are mounted on the cylinder head cover
64
, one above the other. A fuel supply conduit
100
extends from a source of fuel, such as a fuel tank, through a fuel filter
99
(FIG.
2
), to a T-fitting
101
(FIG.
4
). Upper and lower supply conduits extend from the T-fitting
101
to inlet ports
102
of the respective upper and lower fuel pumps
98
. The T-fitting
101
is preferably positioned vertically lower than the inlet port
102
of the lower fuel pump
98
. Thus, the fuel supply conduits preferably follow a generally upwardly-directed path to the fuel pumps
98
.
As shown in
FIG. 4B
, each fuel pump
98
comprises a housing
104
enclosing a pump chamber
106
. The inlet port
102
is provided at a lower portion of the housing
104
. The inlet port
102
is preferably oriented to extend at least partially downward. A discharge port
108
is provided at an upper portion of each fuel pump
98
. The discharge port
108
is preferably oriented to extend at least partially upward.
An inlet valve
110
is positioned adjacent the inlet port
102
. The valve
110
includes a valve seat
112
that is positioned at least partially to the side of the inlet port
102
. A valve element
114
cooperates with the valve seat
112
and is biased to a closed position. The valve element
114
is also arranged to provide one-way flow through the valve
110
in a direction into, but not out of, the pump chamber
106
.
A discharge valve
116
valve is positioned adjacent the discharge port
108
in an upper portion of the fuel pump
98
. The discharge valve
116
includes a valve seat
118
that is positioned immediately adjacent to, but at least partially to the side of, the discharge port
108
. The discharge valve
116
is preferably a one-way valve adapted to allow flow out of, but not into, the pump chamber
106
. A valve element
120
cooperates with the valve seat
118
and is arranged to permit the valve to function in this manner. The valve element
120
desirably is biased toward a closed position.
A diaphragm (not shown) encloses the pump chamber
106
. The diaphragm preferably is actuated by with the intake valve camshaft
56
to alternatively pressurize and depressurize the pump chamber
106
in order to effect flow therethrough. Although the illustrated fuel pumps
98
are powered by rotation of the intake valve camshaft
56
, it is to be understood that fuel pumps
98
having various operating principles may appropriately be used in accordance with the present invention.
A conduit
122
is attached to the top fuel pump discharge port
108
and extends around the side of the engine to a T-fitting
124
, as illustrated in FIG.
5
. The T-fitting
124
is positioned vertically higher than the discharge port
108
. From the T-fitting
124
, a first delivery conduit
126
extends to an uppermost carburetor fuel inlet
128
. The uppermost carburetor fuel inlet
128
is preferably positioned vertically higher than the T-fitting
124
. A second delivery conduit
130
extends from the T-fitting
124
to a lowermost carburetor fuel inlet port
132
. The conduits
122
,
126
from the discharge port
108
to the uppermost carburetor fuel inlet port
128
follow a generally upwardly-directed path. Although portions of the path may extend substantially horizontally, there are preferably no downwardly-extending sections within these lines.
The discharge port
108
of the lower fuel pump
98
also communicates with a conduit
134
which extends around the engine to a T-fitting
136
. A third delivery conduit
138
extends from the T-fitting
136
to a second carburetor fuel inlet
140
. The second carburetor
80
is preferably positioned immediately below the uppermost carburetor
80
. The second carburetor fuel inlet
140
is preferably positioned vertically above the T-fitting
136
, which is positioned vertically above the second fuel pump discharge port
108
. As above, the conduits
134
,
138
follow a generally upwardly-directed path from the lower pump discharge port
108
to the second carburetor fuel inlet
140
. A fourth delivery conduit
142
extends from the T-fitting
136
to a third carburetor fuel inlet port
144
. The third carburetor
80
is preferably positioned below the second carburetor
80
and above the lowermost carburetor
80
.
As best seen in
FIG. 4A
, a bracket
146
secures each T-fitting
124
,
136
onto the cylinder head
50
. Each bracket
146
desirably is attached to a lower branch of the respective T-fitting
124
,
136
and supports a portion of corresponding delivery conduit
130
,
142
attached to the lower branch of the fitting.
The above-described arrangement of fuel pumps
98
and conduits provides advantages in fuel delivery. When air or fuel vapor becomes present in the fuel supply system, the vapor will naturally tend to migrate upwardly with the conduit paths. Vapor that flows into the fuel pumps
98
will naturally move to the top of the fuel pumps
98
. Because the discharge port
108
is oriented towards the top of the fuel pump
98
and because of the orientation of the discharge pump port
108
, the vapor will not accumulate to form a vapor pocket, but will instead naturally migrate out of the pump
98
. Thus, operation of the pump
98
will not be significantly interrupted by the presence of a vapor pocket within the pump
98
.
After the vapor has passed through the pump into the delivery conduits, the vapor will continue to naturally migrate to the uppermost portion of the conduits. In the case of the upper fuel pump
98
, the first conduit
126
proceeds generally upwardly to the uppermost carburetor fuel inlet port
128
. Accordingly, vapor will naturally migrate to the carburetor inlet port
128
, enter the carburetor's fuel bowl, and be vented in a known manner. In the case of the lower fuel pump
98
, an air pocket within the associated fuel delivery conduits will naturally migrate through the third conduit
138
to the second carburetor fuel inlet port
140
, where it enters the carburetor fuel bowl and is vented. In this manner, air or vapor that may be found within the fuel supply system will not create blockages within the system and will not significantly interrupt the fuel supply to the carburetors
80
.
With reference to
FIGS. 6A and 6B
, a cross-sectional view of one of the carburetors
80
is shown. A fuel bowl
147
defines a chamber
148
within the carburetor
80
in which fuel is stored. A wall
150
separates the fuel bowl chamber
148
from a throttle passage
152
. The throttle passage
152
is formed within a throttle body
154
. Air flowing through the intake passage
152
is regulated by a throttle valve
156
. A venturi
158
is formed downstream of the throttle valve
156
to lower the air pressure within the intake passage
152
. A suction port
160
extends into the venturi section
158
and provides a passageway between the intake pipe and the fuel bowl
148
. As air flows through the venturi
158
, fuel from the fuel bowl
148
is drawn through the suction port
160
and into the intake passage
160
, as known in the art.
A float
162
within the fuel bowl
148
actuates a nee valve
164
when the fuel level drops below a predetermined level. Actuation of the needle valve
164
enables fuel from the carburetor fuel inlet port to flow into the fuel bowl
148
, filling the fuel bowl to the predetermined level.
The carburetor preferably includes a pressure relief valve (not shown). Air or vapor that flows into the carburetor from the fuel supply system accumulates within the carburetor. When pressure within the carburetor exceeds a defined limit, the vapor is vented from the carburetor into the intake pipe through the pressure relief valve.
A fuel increasing mechanism is also employed with the carburetors
80
of the engine
14
, as best appreciated from
FIGS. 3 and 5
. In the illustrated embodiment, the fuel increasing mechanism includes a first dash-pot
166
linked to a throttle linkage
168
. The throttle linkage
168
actuates the throttle valves
156
of the carburetors
80
so as to move the valves
156
generally in unison. The linkage
168
also actuates the dash-pot
166
, as described below.
The dash pot
166
includes an air chamber that communicates with each of the fuel bowl chambers
148
through a plurality of air lines. In the illustrated embodiment, as best seen in
FIG. 5
, a first delivery line
170
extends from the dash pot
166
to a T-fitting
172
located on the opposite side of the carburetor bank. One branch of the T-fitting
172
communicates with an air line manifold
174
. The manifold
174
is formed by a plurality of fittings and conduits. Some of the conduits extend between the fittings, and other conduits connect the fittings to air ports
176
on the carburetor bodies
154
that communicate with the corresponding fuel bowl chambers
148
.
The other side of the T-fitting
172
is connected to a second dash pot
178
. The second dash pot
178
is also linked to the throttle valves
156
and is actuated by movement of the throttle valves
156
(i.e., by the corresponding linkage, levers or shafts).
Upon rapid acceleration or deceleration, the throttle valves
156
are opened or closed rapidly. The dash pot produces an air pulse with such quick movement. In the illustrated embodiment, the first dash pot
166
produces such a pulse upon rapid opening of the throttle valves
156
, while the second dash pot
168
produces such a pulse upon rapid closing of the throttle valves
156
. These pulses are delivered to the fuel bowl chambers
148
of the carburetors
80
through the air line manifold
174
. The pulses of air increase the pressure within the fuel bowl chamber
148
and cause an increased amount of fuel to squirt through the suction port
160
. In this manner, an enriched air/fuel charge is delivered to the combustion chambers during periods of rapid acceleration and deceleration in order to improve engine performance and operation.
Although this invention has been described in terms of a certain preferred embodiment, other embodiments apparent to those of ordinary skill in the art are also within the scope of this invention. Accordingly, the scope of the invention is intended to be defined only by the claims that follow.
Claims
- 1. An internal combustion engine having a plurality of variable volume combustion chambers having horizontal axes and oriented so that their axes are arranged above one another, each of the combustion chambers being defined by at least a pair of components that move relative to each other, a plurality of charge formers, each charge former communicating with a corresponding combustion chamber to supply a fuel/air charge to the respective combustion chamber, the charge formers arranged vertically relative to each other, and a fuel supply system connected to the charge formers to deliver fuel to the charge formers, the fuel supply system including a fuel pump having a discharge port communicating through a conduit system with the charge formers, the discharge port being positioned at an uppermost portion of the fuel pump so that the vapor within the pump will migrate toward and through the discharge port into the conduit system, and a discharge check valve positioned adjacent the discharge port, the discharge port being positioned below a fuel inlet port of the uppermost charge former, the conduit system defining a generally upwardly-directed path from the discharge port to the uppermost charge former fuel inlet port, the conduit system adapted so that, at any point within the conduit system, a generally upwardly directed path toward a fuel inlet port of one of the charge formers is defined within the conduit system so that vapors can be smoothly and easily vented from the conduit system to the charge formers.
- 2. The engine of claim 1, wherein the fuel pump is powered by a cam shaft of the engine.
- 3. The engine of claim 1, wherein the discharge port is positioned vertically lower than a fuel inlet port of the charge former.
- 4. The engine of claim 3, wherein the engine includes an output shaft, and the output shaft is adapted to rotate about a substantially vertical axis.
- 5. The engine of claim 4, including a second fuel pump, the second fuel pump having a second discharge port positioned at an uppermost portion of the second fuel pump, and the second fuel pump is oriented vertically below the first fuel pump, and the second discharge port is positioned vertically below a second charge former fuel inlet port.
- 6. The engine of claim 5, including four combustion chambers arranged vertically relative to each other, each communicating with a corresponding charge former, and the first fuel pump communicates with the uppermost charge former and a lowermost charge former, and the second fuel pump communicates with a pair of middle charge formers.
- 7. The engine of claim 1, wherein the charge former includes a fuel bowl having an inlet, and the fuel pump discharge port is positioned vertically below the fuel bowl inlet.
- 8. The engine of claim 1, wherein the discharge port is at least partially upwardly-directed.
- 9. The engine of claim 8, wherein the conduit between the discharge port and the fuel inlet port follows a generally upwardly directed path.
- 10. The engine of claim 9, wherein the fuel pump includes an inlet port, the inlet port being positioned at a lowermost position of the fuel pump.
- 11. The engine of claim 10, including supply conduit communicating between a fuel source and the inlet port, and the supply conduit adjacent the fuel pump follows a generally upwardly directed path.
- 12. An internal combustion engine having at least two variable volume combustion chambers, the combustion chambers having horizontal axes that are arranged above one another, each of the combustion chambers being defined by at least a pair of components that move relative to each other, a plurality of charge formers for supplying fuel/air charges to corresponding combustion chambers, the charge formers also arranged above one another, and a fuel supply system for supplying fuel to the charge formers, the fuel supply system including a fuel pump having a discharge port communicating through a conduit system with the charge formers, the conduit system including means for evacuating vapor which may be in the conduit system so that vapor at any location within the conduit system travels along a path within the conduit system to a charge former for venting from the system without reentering the fuel pump.
- 13. The engine of claim 1, wherein the discharge port is positioned at an uppermost portion of the fuel pump and is at least partially vertically oriented.
- 14. The engine of claim 13, wherein the charge former includes a fuel reservoir having an inlet, and the discharge portion is positioned vertically lower than the inlet.
- 15. The engine of claim 14, wherein the conduit system comprises a first and a second conduit, the first conduit adapted to supply fuel to a first charge former and the second conduit adapted to supply fuel to a second charge former, and the first charge former is positioned vertically higher than the second charge former.
- 16. The engine of claim 15, including a second fuel pump positioned vertically lower than the first fuel pump, and the second fuel pump has a second discharge port that communicates with a third and a fourth conduit, the third conduit communicating with a third charge former and the fourth conduit communicating with a fourth charge former, and the third and fourth charge formers are positioned vertically higher than the second charge former and vertically lower than the first charge former.
- 17. An internal combustion engine having at least three variable volume combustion chambers having horizontal axes and being oriented so that their axes are arranged above one another, each of the combustion chambers being defined by at least a pair of components that move relative to each other, at least three charge formers also arranged above one another, each charge former communicating with a corresponding combustion chamber to supply a fuel/air charge to the combustion chamber, and a fuel supply system connected to the charge formers to deliver fuel to the charge formers, the fuel supply system including a first fuel pump having a discharge port communicating through a conduit with at least two of the charge formers, the discharge port being positioned at an uppermost portion of the fuel pump and being vertically lower than a fuel inlet port of an uppermost charge former and vertically above a fuel inlet port of a lower charge former, and a second fuel pump oriented vertically below the first fuel pump, the second fuel pump having a second discharge port positioned at an uppermost portion of the second fuel pump, the second discharge port being positioned vertically below a fuel inlet port of a middle charge former, the middle inlet port being vertically above the lower inlet port.
- 18. The engine of claim 17, wherein the engine includes an output shaft, and the output shaft is adapted to rotate about a substantially vertical axis.
- 19. The engine of claim 17, including four combustion chambers arranged vertically relative to each other, each communicating with a corresponding charge former, and the first fuel pump communicates with the uppermost charge former and a lowermost charge former, and the second fuel pump communicates with a pair of middle charge formers.
Priority Claims (1)
Number |
Date |
Country |
Kind |
10-239658 |
Aug 1998 |
JP |
|
US Referenced Citations (4)