Vertical engine

Information

  • Patent Grant
  • RE37348
  • Patent Number
    RE37,348
  • Date Filed
    Tuesday, November 17, 1998
    25 years ago
  • Date Issued
    Tuesday, September 4, 2001
    23 years ago
  • US Classifications
    Field of Search
    • US
    • 123 73 AD
    • 123 196 W
    • 123 495
    • 123 447
    • 123 451
    • 123 507
    • 123 509
    • 123 508
    • 123 195 HC
  • International Classifications
    • F02M3706
Abstract
A number of embodiments of high pressure pumps for internal combustion engines having vertically extending output shafts. In each embodiment, the high pressure pump has its pump driving shaft rotatable about an axis that is parallel to the crankshaft axis and is driven by the crankshaft. This arrangement lends itself to application in outboard motors. The high pressure pump includes an integral lubricating pump for lubricating components of the high pressure pump.
Description




BACKGROUND OF THE INVENTION




This invention relates to a vertical engine of the type employed in outboard motors and more particularly to an improved fuel injection system for such vertical engines.




The use of fuel injection for internal combustion engines in order to improve performance, particularly fuel economy and exhaust emission control, is well known. A wide variety of types of fuel injection systems have been proposed for this purpose. Many of these systems inject the fuel into the induction system rather than into the combustion chamber. Such so-called “manifold injected” engines have advantages over carbureted engines. However, there are a number of additional advantages that can be obtained by utilizing direct cylinder injection.




By using direct cylinder injection, it is possible to more accurately control the actual fuel-air ratio in the combustion chamber on each cycle of operation. In addition, by utilizing direct cylinder injection, it is possible to obtain stratification in the combustion chamber and thus operate under a lean mixture under some or most running conditions. That is, by stratifying the charge in the combustion chamber, it is not necessary to have a homogeneous stoichiometric charge in the entire combustion chamber. All that is required is to have a stoichiometric charge present in the vicinity of the spark plug at the time that it is fired in order for combustion to be initiated.




There are, however, a number of reasons why direct cylinder injection is not utilized more widely. Not the least of these is cost. Not only are the injectors more costly and more critical with direct injected engines, but the supply system for supplying fuel to the injectors also becomes more complicated and expensive.




When direct cylinder injection is employed, the injection pressures must not only be higher, but they also must be more accurately controlled. As a result of this, it has been the practice to normally employ reciprocating plunger-type pumps for direct injected engines. Such pumps have a number of components, are complex, and in fact, can become quite bulky.




Although these problems may be overcome in some applications, there is a desire to employ direct cylinder or high pressure fuel injection systems for outboard motors. Like other vehicle applications, outboard matters are subject to concern over environmental control and also fuel economy. In addition, outboard motors frequently utilize two-cycle engines as their power plants. These engines can benefit as much or more from direct cylinder fuel injection as four-cycle engines.




In addition to the cost factor, the complexity of high pressure injection systems makes it more difficult to integrate them into outboard motors. One reason for this is that the outboard motor is a very compact type of device, and it may be difficult to locate the necessary components for a high pressure fuel injection system. In addition, the injection pump normally is driven off of the engine crankshaft and frequently in timed relationship thereto. This further complicates the placement and driving of such high pressure fuel injection pumps in outboard motors.




In addition to these problems, an outboard motor has another problem which is somewhat unique and different from automotive or other vehicle applications. That is, it is normally the practice to mount an outboard motor engine so that its crankshaft rotates about a vertically extending axis. As a result, the orientation of the engine is quite different than automotive and other applications. This further complicates the location and driving of accessories, such as high pressure fuel injection pumps.




When utilizing plunger or piston type high pressure fuel injection pumps, there are a number of mechanical components which are subject to wear. The fuel may not contact all of these components and in many instances, even if the fuel did, it does not have sufficient lubrication properties in order to prevent wear on the components.




For these reasons, it has also been the practice at times to incorporate a separate lubricating system for certain components of the high pressure pump. However, when the engine is mounted so that it its output shaft extends vertically, this further complicates the lubrication system for the fuel injection system and its high pressure pump.




It is, therefore, a principal object of this invention to provide an improved high pressure fuel injection pump for an internal combustion engine.




It is a further object of this invention to provide an improved high pressure fuel injection pump for a vertically disposed engine.




It is yet another object of this invention to provide an improved, compact and high efficiency fuel injection system for an outboard motor.




It is still another object of this invention to provide an improved high pressure fuel injection pump that can be operated with its driving shaft extending in a vertical direction.




It is a still further object of this invention to provide an improved lubricating system for such a vertically disposed high pressure pump.




SUMMARY OF THE INVENTION




This invention is adapted to be embodied in a fuel injected internal combustion engine having an output shaft rotatable about a vertically extending output shaft axis and driven by the combustion occurring in a combustion chamber. A high pressure piston pump is driven by a rotating pump drive shaft that is journaled for rotation about a vertically extending pump drive shaft axis that extends parallel to the engine output shaft axis. Pump driving means are provided for driving the pump drive shaft from the output shaft. A lubricant pump is driven off one end of the pump drive shaft for pumping lubricant to elements of the high pressure pump.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a top plan view of an outboard motor constructed in accordance with an embodiment of the invention, with the protective cowling shown in phantom and also illustrating alternate positions for the high pressure fuel injection pumps in phantom.





FIG. 2

is a schematic view showing the components associated with the fuel injection system, including the high pressure fuel injection pump.





FIG. 3

is an enlarged view which is partially in cross-section through the high pressure pump in accordance with one embodiment of the invention and shows the system components, in part schematically, and thus is related closely to FIG.


2


.





FIG. 4

is a cross-sectional view taken along the line


4





4


of FIG.


3


.





FIG. 5

is a cross-sectional view, in part similar to

FIG. 3

, and shows another of the pump embodiments, which is also shown in phantom lines in FIG.


1


.





FIG. 6

is a cross-sectional view taken along the line


6





6


of FIG.


5


.





FIG. 7

is a partial cross-sectional Kew taken through the cylinder block of a high pressure fuel injection pump constructed in accordance with another embodiment of the invention, which embodiment is also shown in phantom in FIG.


1


.





FIG. 8

is a cross-sectional view taken along the line


8





8


of

FIG. 7

, and shows certain other components of the system schematically.





FIG. 9

is a cross-sectional view, in part similar to

FIGS. 4 and 6

, and shows another embodiment of the invention.





FIG. 10

is a cross-sectional view, in part similar to

FIGS. 4

,


6


and


9


, and shows yet another embodiment of the invention.





FIG. 11

is a partial cross-sectional view, in part similar to

FIGS. 4

,


6


,


9


and


10


, and shows still another embodiment of the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION




Referring now in detail to the drawings and initially to

FIG. 1

, an outboard motor constructed in accordance with an embodiment of the invention is shown partially, with certain components being shown in phantom as well as alternative constructions being shown in phantom, and with portions broken away so as to more clearly show the construction of the basic engine. The invention is described in conjunction with an outboard motor because the invention has particular utility in conjunction with applications where a very compact construction is required, as is the case with outboard motors. In addition, the engine is depicted in conjunction with an outboard motor because outboard motors normally have their crankshafts rotatable about vertically extending axes, and the invention has particular utility in conjunction with engines having such orientations. Finally the invention also has particular utility, but is not so limited, for use with two-cycle crankcase compression internal combustion engines, and such engines are frequently employed as the power units in internal combustion engines.




Because of the fact that the invention deals primarily with the fuel injection system, and specifically the high pressure fuel injection pump therefore, components of the outboard motor which are not necessary to understand the invention are not illustrated. It will be readily apparent to those skilled in the art how the invention can be practiced in conjunction with any known type of outboard motor, if that is the specific application for the invention. Also, the details of the powering internal combustion engine, which engine is indicated generally by the reference numeral


22


, will be described only briefly in order to permit those skilled in the art to understand the orientation of the invention and how it can be utilized with engines of varying types.




In the illustrated embodiment, the engine


22


is depicted as being a V-6, two-cycle, crankcase compression engine, but for the reasons already mentioned, it will be apparent to those skilled in the art how the invention can be utilized with a wide variety of types of engines and engine configurations. In addition, although the invention is described in conjunction with a reciprocating engine, it should also be apparent to those skilled in to an that the invention can be utilized with a wide variety of OEM types at engines, such as rotary engines.




The engine


22


is comprised of a cylinder block


23


which is provided with a pair of angularity disposed cylinder banks


24


. Each cylinder bank


24


is formed with three in-line, horizontally extending cylinder bores in which pistons


25


reciprocate. As is typical with V-type engine practice, the cylinder banks


24


may be staggered axially relative to each other so that connecting rods, indicated by the reference numeral


26


, can connect the pistons


25


to common throws of a crankshaft


27


.




The crankshaft


27


is rotatably journaled within a crankcase chamber


28


that is formed in part by the cylinder block


23


and by a crankcase member that is affixed thereto in any known manner. As is well known in two-cycle crankcase compression engine practice, the crankcase chamber


28


is divided into individual sealed portions, each associated with a respective one of the cylinder bores in which the pistons


25


reciprocate.




The engine


22


is confined within a surrounding protective cowling that is shown in phantom and identified by the reference numeral


29


. Thus, the engine


22


and protective cowling


29


form the powerhead of be outboard motor the vertical disposition of the crankshaft


27


permits its attachment to a drive shaft (not shown) that depends from this powerhead through a drive shaft housing into a lower unit for driving a propulsion unit for propelling an associated watercraft, as is well known in this art.




The protective cowling


29


is formed with a suitable atmospheric air inlet device which preferably is designed so as to permit air to be drawn in for the operation of the engine


22


while, at the same time, excluding water from entering within the protective cowling


29


. This air is then delivered to an induction system, which is indicated generally by the reference numeral


31


, through an air inlet device


32


of that induction system.




The air inlet device


32


may include internal baffling for accomplishing silencing of the inducted air. Air is delivered from the air inlet device


32


through intake pipes


33


to an intake manifold


34


. The intake manifold


34


has individual passages


35


that serve the individual crankcase chambers


29


. A throttle valve assembly (not shown) may be mounted in this intake manifold


34


or in the intake pipes


33


for controlling the speed of the engine.




Reed-type check valves


36


are disposed in each of the manifold runners


35


so as to permit a charge to be drawn into the crankcase chamber portions


28


when the pistons


25


are moving upwardly. When the pistons move downwardly, these reed-type check valves


36


will close and permit the inducted charge to be compressed in the crankcase chambers


28


.




Combustion chambers are formed by the heads of the pistons


25


, the cylinder bores in which they reciprocate, and by cylinder head assemblies


31


which an affixed to the cylinder banks


24


in any known manner, such as by the illustrated but unnumbered fasteners. Each cylinder head assembly


37


has a plurality of recesses


38


which complete the formation of these combustion chambers. The combustion chamber recesses


38


may, at times, be referred to as the combustion chambers since, at top dead center, they comprise the substantial clearance volume of the engine, as best seen in the left-hand side of

FIG. 1

, wherein the piston


25


is shown at this top dead center position.




The charge which has been drawn into the combustion chambers


28


through the induction system


31


and compressed therein is transferred to these combustion chambers


38


through one or mum scavenge passages


39


formed in the cylinder block


23


. This charge is then further compressed in to combustion chambers


38


and eventually fired by a spark plug


41


. Obviously, there is and least one spark plug mounted is each cylinder head


37


for each cylinder. The spark plugs


41


are fired by a suitable ignition system in appropriate timed relationship.




As has been noted, the cylinder heads


37


are assemblies, and these include cover pieces


42


which assist in the formation of water cooling jackets


43


for water cooling of the engine. Such cooling jackets are also formed in other components of the engine


22


as is well known in this art. Water is drawn from the body of water in which the outboard motor operates for circulation through these water jackets in any manner known in this art.




Suitable high pressure fuel injectors, shown schematically and indicated by the reference numeral


41


are also mounted in the cover plates


42


and cylinder head assemblies


37


. These fuel injectors


44


are supplied with high pressure fuel from a fuel supply system which will be described later, and which forms the primary portion of the invention Thus, when the fuel-air mixture is present in the combustion chambers


38


and fired by the spark plugs


41


, the charge will burn and expand and drive the pistons


25


downwardly to drive the crankshaft


27


.




The charge is then expelled through exhaust ports formed in the cylinder block


23


and which communicate with an exhaust manifold


45


formed in the valley between the cylinder banks


24


. This exhaust manifold


45


is also formed by a cover plate assembly


46


which has a further water jacket for cooling of the exhaust manifold


45


. As is typical with outboard motor practice, the exhaust manifold


45


has one or more collector sections, depending upon whether me cylinder banks


24


share a manifold or have separate manifolds.




This collector section extends downwardly and discharges the exhaust gases through an exhaust system, which is typically formed in major part in the drive shaft housing of the outboard motor, as is well known in this art. For the reasons already described, it is not believed that a further description of this known portion of the construction is required to permit those skilled in the art to practice the invention.




The construction of the engine


22


as thus far described may be considered to be conventional, as it has already been noted. For that reason, any further description of the basic structure of the engine


22


or the outboard motor


21


, for that part, is believed to be unnecessary to enable those skilled in the art to practice the invention.




The fuel injection system will now be described in detail, initially primarily to the schematic view of FIG.


2


. It has been noted that the fuel injectors


44


are of any known high pressure type. Since the invention deals primarily with the high pressure fuel injection pump, indicated generally by the reference numeral


47


, the details of the fuel injectors


44


and other components of the injection system will be general in nature, and most of these components are illustrated merely schematically. Again, it will be readily apparent to those skilled in the art how the invention can be practiced in conjunction with any type of conventional components.




There is provided a remotely positioned fuel storage tank


48


which, in typical outboard motor practice, is positioned remotely within the hull of the associated watercraft. Obviously, however, the fuel tank


48


may be contained within the powerhead of the outboard motor


21


, or a small supply tank may be thus located that is served by a remote main tank.




An electrically driven low pressure fuel pump


49


is submerged in the fuel tank


48


below the fuel level therein and discharges fuel through an outlet fitting


51


. This fuel flows in the direction shown by the arrow


52


through a fuel filter


53


, which may be located in the powerhead somewhere within the protective cowling


29


to facilitate servicing. This fuel is then supplied through a conduit


54


to the delivery inlet


55


of die high pressure pump


47


. A low pressure regulator


56


regulates the pressure at which fuel is supplied to the high pressure pump


47


.




Before describing the details of the high pressure pump


47


, the remaining components of the system will be described.




The high pressure pump


47


supplies fuel under a high pressure in pulsed intervals through a pressure conduit


57


to an accumulator


58


. The accumulator


58


has an inlet fitting


59


to which the fuel is delivered. The pressure in the accumulator


58


may be controlled by an electronic control


61


under the direction of a CPU, indicated generally by the reference numeral


62


. This control


61


may also include a distributor arrangement for delivering fuel through respective conduits


63


to the fuel injectors


44


.




It should be noted tat

FIG. 2

shows three fuel injectors


44


which are the fuel injectors associated with one cylinder bank. It has been noted already that the engine


22


is a V-6 engine and hence, there is another bank of fuel injectors. As will become apparent later, the high pressure pump


47


may have banks of plungers or may be of an in-line type, and this will determine to some extent how the fuel is actually supplied from the pump


47


to the individual injectors


44


. Again how this is done forms no major part of the invention.




Returning now to the description of the CPU


62


, this CPU


62


may have any control strategy that operates on input signals from a wide variety of sensors. In the illustrated embodiment, two such sensors are illustrated. These sensors comprise an engine speed sensor


64


which supplies signals not only of engine speed but of crank angle, and an operator demand sensor or load sensor, such as a throttle sensor


65


. Obviously, those skilled in the art will readily understand how the invention may be practiced with a wide variety of types of control strategies.




It has been noted that the low pressure fuel regulator


56


regulates the low pressure supplied to the high pressure pump


47


, and the control


61


of the accumulator


58


regulates the pressure therein. These pressures are regulated by dumping excess fuel back to the fuel tank


48


through respective return conduits


66


and


67


, as is well known in this art.




The construction of the high pressure pump


47


will now be described in detail by reference to

FIGS. 3 and 4

, where the actual construction of the pump is shown, although certain of the auxiliaries associated with it are shown in phantom. The pump


47


is comprised of a main housing assembly


68


which, in the illustrated embodiment, has a pair of opposed cylinder banks


69


. In the illustrated arrangement, each bank


69


contains one pumping assembly. It will be readily apparent to those skilled in the art, however, that the number of pumping assemblies employed can be increased, and one way in which this may be done will be described later, when the actual pumping mechanisms are described.




The banks


69


are each provided with respective cylinder heads


71


that are affixed thereto in any known manner. The cylinder head of one bank is provided with a T-shaped fitting


72


that receives the end of the conduit


54


for supply thereto. The T-fitting


72


has a branch that supplies a further conduit


73


which extends, as indicated at a, to a corresponding inlet fitting


74


of the cylinder head


71


of the other cylinder bank.




The construction of these cylinder heads


71


appears in most detail in FIG.


4


. It will be seen that each cylinder head


71


includes a delivery check valve


75


that cooperates with an inlet fitting


76


to permit the fuel to be drawn into a pumping chamber


77


. This pumping chamber


77


communicates with a pumping bore


78


in which one end of a pumping plunger


79


is slidably supported. An O-ring seal


81


encircles the pumping plunger


79


and provides a fluid seal therearound.




The pumping plunger


79


is reciprocated, in a manner to be described, and when the volume of the pumping chamber


77


is increasing, fluid will be drawn into this pumping chamber through die opening of the delivery check valve


75


. When the volume of the pumping chamber


77


is being decreased by the upward movement of the pumping plunger


79


, high pressure will be generated and it will open a discharge check valve


82


to permit fluid to be discharged through a fitting


83


to the conduit


57


which communicates with the accumulator chamber


58


. An outlet fitting


84


is provided for communication between the fitting


83


and the conduit


57


.




Turning now to the operation for reciprocating the pumping plungers


74


, it will be seen that the banks


69


of the housing assembly


68


are formed with bores


85


that are concentric with the pumping chamber portion


78


. The pumping plungers


100


have a shank portion


86


that has a yoke part


87


at its bottom end that A urged by a coil compression spring


88


into engagement with a piston or tappet-type actuator


89


. At the opposite end, the spring


88


acts against a closure plug


91


that closes the upper end of the bore


85


and which slidably supports the pumping plunger


79


. An O ring seal


90


seals the plugs


91


to the housing


69


.




The piston or tappet actuator


89


is held against rotation by means of a set screw


92


and carries a roller follower


93


which is journaled on a shaft


94


by a needle-bearing assembly


95


. The spring


88


in addition to urging the pump plunger yoke


87


into engagement with the actuating tappet


89


, also urges the tappet into engagement with a drive cam


96


of a pump drive shaft, indicated generally by the reference numeral


97


.




Referring now primarily to

FIG. 3

, it will be seen that the housing assembly


68


has an upwardly extending cylindrical portion


98


and a downwardly extending larger diameter cylindrical attachment piece


99


. The upper portion


98


rotatably journals the pump drive shaft


97


through a first thrust bearing


101


. Disposed above the thrust bearing


101


is an oil set


102


that defines a lubricant receiving chamber


103


, for a purpose which will be described.




The pump drive shaft


97


continues upwardly into and through a cover plate


104


that is held in place by threaded fasteners


105


. This cover plate


104


permits the pump drive shaft to enter into a drive cavity formed by a timing drive cover


106


that is comprised of a lower portion


107


and an upper portion


108


, which may be of any known construction and which are shown primarily in phantom in the figures. Reference also should be had to

FIG. 1

for this construction.




This contains a timing drive, indicated generally by the reference numeral


109


, which consists of a chain


111


or other flexible transmitter such as a toothed belt that is driven by a drive sprocket


112


that is affixed to either the upper or lower end of the crankshaft


27


. This drive chain


111


is in engagement also with a the sprocket


113


that is held to the upper end of the pump drive shaft


97


by means of a retainer plate assembly


114


and a nut


115


threaded onto the upper end of the pump drive shaft


97


. Finally, a drive key


116


interconnects the sprocket


113


with the pump drive shaft


97


to provide a timed driving connection therebetween.




Referring now again primarily to

FIG. 3

, the lower end of housing attachment


90


as has been noted, is of a larger diameter than the upper portion


90


This is to permit it to form a combined oil reservoir and pump cavity


117


, the lower end of which is closed by a closure plate


118


. An oil pump assembly, indicated generally by the reference numeral


119


, is driven off of the lower end of the pump drive shaft


97


. This oil pump assembly


119


may be comprised of a gerotor-type pump that realms oil in a pumping cavity


121


from the reservoir


117


and pressurizes it. Oil is delivered through delivery ports


122


and


123


.




The oil is pumped under high pressure through a first conduit


124


that extends axially through the pump drive shaft


97


from the pumping cavity


121


, and specifically its outlet, to a cross-drilling


125


that communicates with the lubricant cavity


103


so as to lubricate the upper bearing


101


. This lubricant then flows downwardly so as to lubricate the cams


96


, roller followers


93


, needle bearings


95


and pin


94


. In addition, same of this lubricant will also lubricate the lower end of the pump driving pistons or tappets


89


. An oil cavity


126


is formed around the pump driving elements for assisting in this lubrication.




The lower pump housing portion


99


supports a second thrust bearing


127


which receives the down-flowing lubricant from the cavity


126


and permits it to drain back into the reservoir cavity


117


.




In addition to this lubricant path, the pump


119


further delivers lubricant under pressure through a passageway


128


formed between the pump housing member


99


and the cover plate


118


, which communicates with a further main supply passageway


129


. The main supply passageway


129


extends upwardly, as shown in

FIG. 4

, and intersects a drilled passageway


131


which is drilled through the pump housing


69


, and is intersected by a pair of cross-drillings


132


, each of which extends to the respective plunger supporting closure elements


91


, These elements are provided with cross-drillings that extend from circumferential grooves


133


formed therein to inner circumferential grooves


134


that surround the pump plungers


79


. These cross-drillings are indicated by the reference numeral


135


in the drawings. This oil will flow into the bores


85


and can drain back into the cavity


126


for return to the reservoir


117


.




As should be readily apparent from the foregoing description, the configuration and orientation of the high pressure pump


47


permits it to be conveniently mounted in the valley between the cylinder heads


37


adjacent the pressure accumulator


58


so as to provide a very compact assembly and one which is located close to the actual fuel injectors


44


so as to minimize the length of the conduits. In addition, the vertical disposition of the pump drive shaft


97


permits it to drive its own lubricating pump off the lower end thereof, and lubricant can be returned to the reservoir of this pump through a gravity return system. Hence, the structure is not only compact, but it is also well lubricated and well protected.




A high pressure oil pump constructed in accordance with another embodiment of the invention is illustrated in

FIGS. 5 and 6

and is indicated generally by the reference numeral


201


. The pump


201


is employed in a system of the type as previously described and thus, many components associated with this pump are the same or substantially the same and have been identified by the same reference numeral when that is the case.




In the previously described embodiment, the high pressure pump


47


was of the opposed piston type, whereas the embodiment of

FIGS. 5 and 6

shows an in-line type of pump. Therefore, the pump body


202


is formed with in-line bores that receive the plunger mechanisms and which are closed by a cylinder head assembly, indicated generally by the reference numeral


203


. Each pumping unit is the same as that previously described and, for that reason, the components of the pumping elements which are the same in construction and operation as those already described have been identified by the same reference numerals and will be described again only insofar as is necessary to understand the construction and operation of this embodiment.




The drive for the pump shaft


97


is also the same as that previously described and, for that reason, this mechanism also will not be described again in detail. In this embodiment, since the outer housing


202


is formed with aligned cylinder bores that receive the pumping plunger actuating pistons or tappets


89


, it is higher than the previously described embodiment. However, because of this disposition, it is shorter in width and thus can be located, for example, on one side of one of the cylinder banks


24


. Such an alternative location is shown in

FIG. 1

by the phantom line view.




In view of this location, a shorter drive chain


204


or a flexible timing belt may be employed, which is still driven by the crankshaft sprocket


112


and which drives the pump shaft


97


by a pump drive sprocket


113


. This type of pump lends itself better to an arrangement wherein it is utilized with an in-line engine, but can be utilized with a V-type engine with either a slot pump on one side of the one cylinder bank


24


or with individual pumps on one side of each cylinder bank, as illustrated.




As may be seen, the pump drive shaft, therefore, has three pump actuating cams


96


-


1


,


96


-


2


and


96


-


3


. As has been previously noted, the V-type or opposed-type pump, like the pump


47


, may also be employed with multiple plunger cylinders, and these would embody such an extended cam shaft having a greater number of pump plungers.




With this arrangement, however, there is a simpler disposition of the manifolding for supplying fuel to and from the pump


201


and accordingly, a single fluid inlet conduit


205


may be provided that supplies all of the delivery valves


75


for this embodiment. The communication between the delivery valves


15


can be formed internally in the cylinder head


203


. In addition, a single pump discharge fitting


206


can be mounted in the cylinder head


203


and is served by internal conduits which communicate with each of the pump delivery check valves


82


.




Because of the greater length of the pump shaft


97


in this embodiment, a different arrangement is provided for the lubricant and the reservoir therefore. In this embodiment, a gerotor-type pump, indicated generally by the reference numeral


207


and having a pumping cavity


208


, is formed between a lower housing member


209


that is fixed to the main housing member


202


in a suitable fashion, and closed by a closure plate


211


. A drain reservoir


212


below the lowermost pump drive shaft bearing


127


collects the oil and returns it to the pumping cavity


208


through a drain passageway


213


. The lubricant is then delivered under pressure by the pumping element of the gerotor pump


207


to a high pressure discharge


214


which communicates with a delivery passage


215


. The passage


215


, in turn, communicates with a fitting


216


and through a pressure responsive check valve


217


with an oil reservoir


218


. A port


219


in the housing piece


202


permits this communication.




A discharge passageway


221


extends from this reservoir cavity


218


to an oil delivery check valve


222


positioned in a pressure fitting


223


. The pressure fitting


223


communicates with a drilled passageway


224


(

FIG. 6

) which, in turn, supplies oil to the oil delivery grooves


133


of each of the pump plunger supports


91


in this embodiment.




A separate passageway (not shown) may extend from the pump pressure cavity


214


to a point above the uppermost pump drive shaft support bearing


101


for its lubrication. Again, the oil will drain through the return path as aforedescribed.




The invention has been described thus far in conjunction with opposed-type and in-line-type of high pressure fuel pumps. Another embodiment appears in

FIGS. 7 and 8

and provides a V-type high pressure fuel pump, indicated generally by the reference numeral


251


. This type of fuel pump may be easily incorporated in conjunction with a V-type engine, and one possible location is shown in phantom in FIG.


1


. In this location the pump can be disposed compactly to the engine


22


because of both units V shaped configuration as seen in FIG.


1


.




Again, be pump


251


basically has the same pumping plunger arrangements as those previously described and, for that reason, where components of this embodiment are the same or substantially similar to those previously described, will be identified by the same reference numerals, or the parts are not shown, because it is believed that those skilled in the art will readily understand the arrangement of the components. In this embodiment the pump


251


is designed for a four cylinder engine, but obviously this pump may be used with engines having any number of cylinders.




In this embodiment the pump


251


includes a cylinder block


252


that has a pair of aligned banks, each of which is adapted to receive a pumping assembly, indicated generally by the reference numerals


253


, which comprise the pumping plungers, delivery lines and actuators as previously described. One cylinder bank extends generally parallel to one of the engine cylinder banks


24


. The other pump cylinder bank is perpendicular to the first one.




These elements are mounted primarily in bores


254


formed at the lower portion of the pump receiving cavities, wherein the piston actuators, which are not shown, can operate with cam lobes


255


formed integrally on the cam shaft, which is indicated by the same reference numeral as previously applied, i.e.,


97


.




In this embodiment, the accumulator chamber


58


may be formed by a bore


256


that is formed integrally in the cylinder block


252


in the area between the bores


253


that receive the pumping mechanism. Internal cavities


257


perform the function of the supply conduits


57


from the previously described embodiments which supply the high pressure fluid to the accumulator chamber


256


. A pressure regulator may be contained within this assembly and hence, the high pressure regulated fuel return line


67


is connected directly to the fuel tank


48


for this return.




This embodiment employs a more compact lubricant pump, which can have the same construction as that of the embodiments of

FIGS. 5 and 6

, and which is, therefore, identified by the same reference numeral


207


. In all other regards, this embodiment is the same as those previously described.




A driving sprocket


258


is affixed to the upper end of the pump drive shaft


97


and is driven by a chain


259


or a flexible timing belt off of the crankshaft driving sprocket


112


, as shown in FIG.


1


.




In the embodiments of the invention as thus far described, the pumping plungers have all been actuated directly by cams on the pump drive shaft.

FIG. 9

shows another embodiment which employs a rocker arm actuation and hence, can achieve greater strokes for a given cam lift or strokes which can be varied if desired.




A pump constructed in accordance with this embodiment is identified generally by the reference numeral


301


and is shown only in a single cross-sectional view, because it is believed readily apparent to those skilled in the art, from the foregoing description, how the invention may be employed with varying numbers of plungers and varying orientations for them, such as in-line, V-type, etc., as previously described.




In this embodiment, the pump


301


includes an outer housing assembly


342


which defines a cavity


303


in which the pump drive shaft


304


is journaled for rotation in a manner as previously described. The pump drive shaft


304


has one or more cam lobes


305


that engage the follower portion


305


of a rocker arm, indicated generally by the reference numeral


307


. The rocker arm or rocker arms, if more than one are employed, are rotatably journaled on a rocker arm shaft


308


that extends parallel to the axis of rotation of the pump drive shaft


304


. As with all of the previously described embodiments, this pump drive shaft


304


rotates about an axis that is parallel to the axis of rotation of the crankshaft


27


and which, accordingly, is vertically disposed.




The rocker arm


307


has a further arm portion


309


that carries an adjustable follower


311


having a spherical portion


312


that is engaged with a yoke portion


313


of the pumping plunger, indicated generally by the reference numeral


314


. The pumping plunger


314


has a shank or plunger portion


315


which is supported in a pump support element


316


which is affixed in the housing


302


and which has an O-ring seal


317


that provides a seal therewith.




A valve body and distribution member


318


is affixed to the main pump housing


302


with an O-ring seal


319


encircling the plunger supporting member


316


and providing a seal therebetween. A pumping chamber


3211


formed in the member


318


and receives the pumping end of the pumping plunger


315


. A return spring


320


acts between the plunger support member


316


and the yoke portion


313


of the pumping plunger


315


to urge it into engagement with the adjustable follower


312


and to return it on its intake stroke.




Fuel is delivered to the pumping chamber


321


through an inlet fitting


322


which communicates with a delivery port


323


. The low pressure regulator


324


communicates with this area and, as aforenoted, regulates the pressure from the low pressure pump by returning fluid to the fuel tank


48


through the return conduit


66


.




A delivery check valve


325


permits fuel to flow into the pumping chamber


321


when the pumping plunger


311


is moving downwardly and precludes reverse flow as it moves upwardly. Upon upward movement, the fuel is compressed and discharged through a delivery check valve


326


to the accumulator chamber


58


through a supply passage


327


and a supply fitting


328


.




Like the previously described embodiments, the mechanism is also lubricated by a lubricant pump that is driven off the lower end of the pump drive shaft


304


in a manner as previously described. The lubrication system for the pumping plunger


315


appears in this figure and it includes the outer supply game


329


that communicates with an inner lubricating groove


331


through a plurality of drilled passages


332


, as with the previously described embodiments.





FIG. 10

shows another type of pump plunger actuating mechanism, and since this type of mechanism may be employed with any of the pump assemblies as previously described, only the plunger actuating mechanism will be described. Unlike the previously described cam and follower mechanisms, this mechanism employs a Geneva or segmented gear-type drive, indicated generally by the reference numeral


351


. A segmented gear having teeth segments


352


is affixed for rotation with the pump driving shaft


353


. The teeth


352


are adapted to selectively engage follower ribs


354


formed on an extension


355


of the pump plunger, indicated generally by the reference numeral


356


to drive the plunger


356


sequentially. The pump plunger


356


has a shoulder portion


357


that is engaged by a spring


358


for urging the plunger to a retracted position in the pumping bore


359


formed by a cylinder head member


361


.




The opposite end of the spring


358


acts against a plunger retainer element


362


which, like the previously described embodiments, provides an arrangement for lubricating the pump plunger


356


. This member


362


has an O-ring seat


363


that engages the pump housing


364


for sealing therewith. A similar seal


365


is disposed between the end of the plunger supporting member


362


and the cylinder head


361


.




An oil supply game


366


receives oil from an oil pump driven off the lower end of the pump drive shaft


353


. This oil is then delivered to lubricate the plunger


356


through drilled passageways


367


and a lubricant supply groove


368


that extends around the pump plunger within the member


362


.





FIG. 11

shows another embodiment driven similar to the embodiment of FIG.


10


. In this embodiment, however, there are two Geneva gear mechanisms


401


and


402


that operate so that their teeth


403


and


404


are respectively out of phase with the ribbed members


354


on the pumping plunger. These Geneva gear mechanisms


401


and


402


are driven by a pump drive shaft (not shown) and rotate in the same direction and at the same speed, but at a different phase to each other as noted. Thus, this mechanism is capable of supplying more pumping strokes during a given cycle.




From the foregoing description, it should be readily apparent that the embodiments of the invention are extremely effective in providing a high pressure pump for a vertical engine that can have a compact construction and thus, may be conveniently placed-relative to the engine. In addition, the pump shaft rotates about a vertically extending axis to simplify the drive from the vertically extending output shaft to the engine. Lubricating systems are incorporated within the pump mechanism for its lubrication.




It should be readily apparent to those skilled in the art that the foregoing descriptions at don of preferred embodiments of the invention, and that various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.



Claims
  • 1. A fuel injected internal combustion engine having an output shaft rotatable about a vertically extending output shaft axis and driven by the combustion within the engine, a high pressure piston pump driven by a rotatable pump driving shaft journaled for rotation about a vertically extending pump drive axis and extending parallel to said engine output shaft axis, pump drive means for driving said pump drive shaft from said engine output shaft, and a lubricant pump driven off one end of said pump drive shaft for pumping lubricant to the elements of said high pressure pump.
  • 2. The fuel injected internal combustion engine of claim 1, wherein the engine is a reciprocating engine and the engine output shaft comprises a crankshaft.
  • 3. The fuel injected internal combustion engine of claim 1, wherein the lubricant pump is driven off the lower end of the pump drive shaft.
  • 4. The fuel injected internal combustion engine of claim 1, wherein the pump drive shaft drives at least two pumping plungers.
  • 5. The fuel injected internal combustion engine of claim 4, wherein the pumping plungers are disposed at an angle to each other, but in the same vertical plane.
  • 6. The fuel injected internal combustion engine of claim 5, wherein the pumping plungers are opposed to each other.
  • 7. The fuel injected internal combustion engine of claim 4, wherein the pumping plungers are arrayed in a vertical plane.
  • 8. The fuel injected internal combustion engine of claim 7, wherein each pumping plunger is driven by a separate cam lobe.
  • 9. The fuel injected internal combustion engine of claim 3, wherein the pump drive shaft is supported by a pair of spaced apart bearings and wherein the lubricant pump delivers lubricant to the bearings.
  • 10. The fuel injected internal combustion engine of claim 9, wherein the lubricant pump further delivers lubricant to the pumping plunger for the lubrication of the pumping plunger.
  • 11. The fuel injected internal combustion engine of claim 10, wherein the lubricant from the pumping plunger and the bearings is returned by gravity to the lubricant pump.
  • 12. The fuel injected internal combustion engine of claim 2, wherein the lubricant pump is driven from the engine output shaft by a flexible transmitter.
  • 13. The fuel injected internal combustion engine of claim 12, wherein the flexible transmitter comprises a chain.
  • 14. The fuel injected internal combustion engine of claim 1, wherein the engine comprises the power plant of a marine outboard drive.
  • 15. The fuel injected internal combustion engine of claim 14, wherein the engine is a reciprocating engine and the engine output shaft comprises a crankshaft.
  • 16. The fuel injected internal combustion engine of claim 14, wherein the lubricant pump is driven off the lower end of the pump drive shaft.
  • 17. The fuel injected internal combustion engine of claim 14, wherein the pump drive shaft drives at least two pumping plungers.
  • 18. The fuel injected internal combustion engine of claim 17, wherein the pumping plungers are disposed at an angle to each other, but in die same vertical plane.
  • 19. The fuel injected internal combustion engine of claim 18, wherein the pumping plungers are opposed to each other.
  • 20. The fuel injected internal combustion engine of claim 17, wherein the pumping plungers are arrayed in a vertical plane.
  • 21. The fuel injected internal combustion engine of claim 20, wherein each pumping plunger is driven by a separate cam lobe.
  • 22. The fuel injected internal combustion engine of claim 16, wherein the pump drive shaft is supported by a pair of spaced apart bearings and wherein the lubricant pump delivers lubricant to the bearings.
  • 23. The fuel injected internal combustion engine of claim 22, wherein the lubricant pump further delivers lubricant to the pumping plunger for the lubrication of the pumping plunger.
  • 24. The fuel injected internal combustion engine of claim 23, wherein the lubricant from the pumping plunger and the bearings is returned by gravity to the lubricant pump.
  • 25. The fuel injected internal combustion engine of claim 15, wherein the lubricant pump is driven from the engine output shaft by a flexible transmitter.
  • 26. The fuel injected internal combustion engine of claim 25, wherein the flexible transmitter comprises a chain.
  • 27. The fuel injected internal combustion engine of claim 14, wherein the engine comprises a reciprocating engine and the engine output shaft comprises a crankshaft driven by a pair of pistons slidably supported in a cylinder block having opposed cylinder banks, each defining at least one bore receiving respective one of said pistons.
  • 28. The fuel injected internal combustion engine of claim 27, wherein the high pressure pump is disposed in a valley between the cylinder banks.
  • 29. The fuel injected internal combustion engine of claim 28, wherein the high pressure pump has at least two plungers driven by the pump driving shaft and which are disposed in opposed relationship to each other.
  • 30. The fuel injected internal combustion engine of claim 27, wherein the high pressure pump is disposed adjacent one side of one of the cylinder banks of the engine.
  • 31. The fuel injected internal combustion engine of claim 30, wherein the pump has a plurality of pumping plungers disposed in a vertically arranged plane and which lie at a complementary angle to the angle of the cylinder bank.
  • 32. The fuel injected internal combustion engine of claim 27, wherein the high pressure pump has a pair of pumping plungers disposed at a V angle to each other and is disposed on one side of one of the cylinder banks.
  • 33. The fuel injected internal combustion engine of claim 32, wherein one of the pumping plungers reciprocates along an axis that is generally parallel to the axis of the cylinder bore of the adjacent cylinder bank and the other of the pumping plungers reciprocates along an axis that is generally perpendicular to the axis of the first pumping plunger.
  • 34. An outboard motor comprised of a power head consisting of an internal combustion engine and a surrounding protective cowling and a driveshaft housing and lower unit containing a propulsion device within said lower unit depending from said power head, said engine being mounted within said protective cowling so that its crankshaft rotates about a vertically-extending axis, said crankshaft being coupled to a drive shaft that depends into said driveshaft housing and lower unit for driving said propulsion device, said engine being formed with a plurality of combustion chambers, a plurality of fuel injectors for injecting fuel directly into respective of said combustion chambers, a high pressure fuel pump contained within said protective cowling and having a pumping element reciprocating along a horizontal axis for pressurizing fuel for delivery to said fuel injectors, and a mechanical transmission for driving said pumping element from said crankshaft for delivering, high pressure fuel to said fuel injector.
  • 35. An outboard motor as set forth in claim 34 wherein the pumping element is operated by a rotating cam.
  • 36. An outboard motor as set forth in claim 35 wherein the rotating cam rotates about a vertically extending axis that is parallel to the axis of rotation of the crankshaft.
  • 37. An outboard motor as set forth in claim 36 wherein the rotating cam is positioned externally of the engine body.
  • 38. An outboard motor as set forth in claim 37 wherein the rotating cam is fixed for rotation with a camshaft that is directly driven by the crankshaft through a flexible transmitter.
  • 39. An outboard motor as set forth in claim 34 wherein the engine is a spark ignited engine.
  • 40. An outboard motor as set forth in claim 39 wherein the fuel injectors, inject fuel directly into the combustion chambers.
Priority Claims (1)
Number Date Country Kind
6-300350 Nov 1993 JP
US Referenced Citations (13)
Number Name Date Kind
4412513 Obermayer et al. Nov 1983
4480623 Thomas Nov 1984
4557235 Amemori et al. Dec 1985
4976591 Rivas et al. Dec 1990
5052897 Yamashita et al. Oct 1991
5081970 Matsuoka Jan 1992
5603303 Okajima et al. Feb 1997
5806499 Stover et al. Sep 1998
5865655 Hiraoka et al. Feb 1999
5878710 Ritter et al. Mar 1999
5957673 Kampichler et al. Sep 1999
5975060 Stover et al. Nov 1999
5992392 Saito Nov 1999
Foreign Referenced Citations (1)
Number Date Country
2 140 083 Nov 1984 GB
Divisions (1)
Number Date Country
Parent 08/556065 Nov 1995 US
Child 09/195459 US
Reissues (1)
Number Date Country
Parent 08/556065 Nov 1995 US
Child 09/195459 US