Engine with oil pump

Information

  • Patent Grant
  • 6450783
  • Patent Number
    6,450,783
  • Date Filed
    Friday, November 17, 2000
    24 years ago
  • Date Issued
    Tuesday, September 17, 2002
    22 years ago
Abstract
An oil pump includes an oil supply pump and an oil recovery pump disposed on an extension line of a crankshaft of an engine. One joint member is provided at an end portion of the crankshaft, and another joint member is provided at an end portion of a pump shaft. The two joint members are coupled to each other on the same axial line within a front cover of an engine. The two joint members have alternating concave portions and convex portions. The convex portions of the two joint members include inclined faces and opposing driving transmission faces. The inclined faces of the convex portions guide the convex portions into the concave portion of the opposing joint member, so that the two joint members are meshed with one another. The crankshaft side joint member is fastened together with an ACG rotor. An oil tank connected to the oil pump is disposed above and very close to the oil pump.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an engine having an oil pump. More particularly, the present invention relates to a coupling structure, or a driving transmission structure, between a crankshaft of the engine and a pump shaft of the oil pump.




2. Description of the Background Art




A conventional engine having an oil pump is shown in

FIGS. 9 and 10

, which are from the official gazette of Japanese Patent Laid-Open No. Hei. 9 301286. The engine


1


shown in

FIGS. 9 and 10

is carried on a small-sized boat. The engine


1


includes a supply pump


2


(see

FIG. 10

) for supplying oil from an oil tank


4


into the engine


1


, and a recovery pump


3


for recovering oil, which has lubricated the inside of the engine


1


, into the oil tank


4


. The pumps


2


and


3


are disposed on shafts


2




a


and


3




a


which extend in parallel to a crankshaft


5


of the engine, and are driven to rotate by the crankshaft


5


through a transmission gear (not shown). Since the pumps


2


and


3


of the engine


1


described above are each respectively disposed on the shafts


2




a


,


3




a


parallel to the crankshaft


5


, and are driven to rotate by the crankshaft


5


through the transmission gear (not shown), there is a disadvantage that the driving structure therefor is complicated, and also an increased number of parts are required.




SUMMARY OF THE INVENTION




It is therefore an object of the present invention to provide an engine with an oil pump wherein the oil pump can be driven with a simple structure and also the number of parts is decreased. To attain the object described above, an oil pump is disposed on an extension line of a crankshaft of the engine, and a coupler interconnects the crankshaft to a shaft of the oil pump. The coupler includes a first joint member provided at an end portion of the crankshaft, and a second joint member provided at an end portion of the shaft of the oil pump. The two joint members are coupled to each other on the same axial line within a cover of the engine.




The joining portions of both joint members are formed with concave and convex portions. Faces of the convex portions which oppose driving transmission faces of the convex portions are formed as inclined faces for guiding the convex portions of the opposing joint member. The joint member on the crankshaft is secured by being fastened together with an ACG rotor provided at an end portion of the crankshaft.




Because the oil pump is disposed on an extension line of the crankshaft, and the joint member provided at an end portion of the crankshaft and the joint member provided at an end portion of the pump shaft are coupled to each other on the same axial line, the requirement for a conventionally required transmission gear is eliminated. In the present invention, the oil pump can be driven with a simple structure, and the number of parts can be reduced. Further, since the two joint members are coupled to each other within the cover of the engine, the space for coupling the crankshaft and the pump shaft to each other may be small. However, because the coupler is located within the cover and cannot be visually observed, there is the possibility that the coupling operation may be difficult.




In the present invention, even if the coupling portions of the two joint members are within the cover and cannot be visually observed, the coupling operation can be readily performed since the joining portions of the two joint members are formed with the concave and convex portions, wherein faces of the convex portions which oppose driving transmission faces of the convex portions are formed as inclined faces for guiding the convex portions of the opposing joint member.




As described above, with the present invention, the oil pump can be driven with a simple structure, and the number of parts can be reduced. In addition, while the space for coupling the crankshaft and the pump shaft may be small, the coupling operation of the two joint members can be performed readily. Also, since the joint member of the crankshaft side is secured by being fastened together with the ACG rotor which is provided at an end portion of the crankshaft, the ACG rotor and the joint member can be provided efficiently in a small space with a small number of parts.




An oil tank is connected to the oil pump, and is disposed above and very close to the oil pump. The oil pump includes an oil supply pump and an oil recovery pump which are driven to rotate by a common shaft. Since the oil tank is disposed above and very close to the oil pump, the space above the oil pump can be utilized efficiently, and members around the engine can be compactly configured. In addition, since pipes for connecting the oil pump and the oil tank to each other can be made short, oil can be circulated efficiently.




Since the oil supply pump and the oil recovery pump are rotated by a common shaft, the engine can be compactly formed when compared with an engine of the configuration wherein the oil supply and oil recovery pumps are disposed on individual shafts, and driven to rotate by transmissions as in the conventional engine with an oil pump shown in FIG.


10


.




Where the oil supply pump and the oil recovery pump are driven to rotate by the common shaft, although the length of the pump in its axial line direction becomes comparatively large, the space above the oil pump can be utilized effectively by disposing the oil tank above and very close to the oil pump, and members around the engine can be compactly configured. In addition, not only it is possible to make the pipes for connecting the oil pump and the oil tank to each other short to augment the circulation efficiency of oil, but it is also possible to concentrate the pipes for the oil supply pump and the pipe for the oil recovery pump.




Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.











BRIEF DESCRIPTION OF THE DRAWINGS




The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:





FIG. 1

is a schematic side elevational view, partly broken, showing an example of a saddle type small-sized boat on which an embodiment of an engine with an oil pump according to the present invention is carried;





FIG. 2

is a top plan view of the saddle type small-sized boat;





FIG. 3

is a sectional view of a front portion of an engine;





FIG. 4

is a diagram of a circulation route of oil;





FIG. 5

is a rear elevational view of a joint member mounted on a pump shaft;





FIG. 6

is a cross-sectional view of the joint member taken along line VI—VI of

FIG. 5

;





FIG. 7

is a front elevational view of a joint member mounted on a crankshaft;





FIG. 8

is a sectional view a joint member mounted on a crankshaft taken along line VIII—VIII of

FIG. 7

;





FIG. 9

is an explanatory view of the prior art; and





FIG. 10

is an explanatory view of the prior art.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




An embodiment of the present invention will now be described with reference to the drawings. As shown in

FIGS. 1 and 2

, the saddle type small-sized boat


10


can be steered by a steering handle bar


13


with a throttle lever gripped by a passenger seated on a seat


12


on a boat body


11


.




The boat body


11


has a floating body structure wherein a lower hull panel


14


and an upper hull panel


15


are joined together with a space


16


formed therebetween. In the space


16


, an engine


20


is placed on the lower hull panel


14


, and a jet pump


30


serving as propelling means driven by the engine


20


is provided at a rear portion of the lower hull panel


14


.




The jet pump


30


has a flow path


33


extending from an intake


16




a


opened to the bottom of the boat to a jet


31


opened to a rear end of the boat body, and a nozzle


32


. An impeller


34


is disposed in the flow path


33


, and a shaft


35


of the impeller


34


is connected to a rear end of a crankshaft


21


of the engine


20


. Accordingly, if the impeller


34


is driven to rotate by the engine


20


, then water taken in through the intake


16




a


is jetted from the jet


31


past the nozzle


32


, whereby the boat body


11


is propelled. The driving speed of the engine


20


, that is, the propelling force by the jet pump


30


, is controlled by a revolving operation of a throttle lever


13




a


(refer to

FIG. 2

) of the steering handle bar


13


described above. The nozzle


32


is associated with the steering handle bar


13


by a control wire (not shown) and is controlled to be turned by an operation of the handle bar


13


, whereby the advancing direction can be changed.




Referring now to

FIGS. 3 and 4

, the engine


20


is a DOHC straight four-cylinder four-cycle engine. An oil pump


40


is disposed on an extension line of the crankshaft


21


at a forward portion of the engine


20


with respect to an advancing direction of the boat body


11


. The oil pump


40


includes an oil supply pump


41


and an oil recovery pump


42


. The two pumps


41


and


42


are driven to rotate by a common pump shaft


43


.




A joint member


44


is secured to a rear end portion of the pump shaft


43


by means of a bolt


45


, and another joint member


24


is secured to a front end portion of the crankshaft


21


by means of a bolt


22


. The joint member


24


of the crankshaft


21


side is secured by being fastened together with an ACG rotor


23


, which is provided at a front end portion of the crankshaft


21


, by means of the bolt


22


.




Referring now to

FIGS. 5 and 6

, the joint member


44


mounted on the pump shaft


43


has plural (in the present embodiment, four) convex portions


44




a


and concave portions


44




b


disposed alternately along a circumferential direction thereof. Further, as shown in

FIGS. 7 and 8

, the joint member


24


mounted on the crankshaft


21


has the same number of convex portions


24




a


and concave portions


24




b


as that of the concave and convex portions of the joint member


44


along a circumferential direction thereof. When the two joint members are coupled to each other on the same axial line, the concave and convex portions of the two joint members mesh and fit with each other. In particular, the convex portions


44




a


of the joint member


44


fit in the concave portions


24




b


of the joint member


24


, and the convex portions


24




a


of the joint member


24


fit in the concave portions


44




b


of the joint member


44


, respectively.




The joint member


24


of the crankshaft


21


side rotates in the clockwise direction in

FIG. 7

as indicated by the arrow in the figure, and the joint member


44


of the pump shaft


43


side is driven to rotate in the counterclockwise direction in

FIG. 5

as indicated by the arrow in the figure. Consequently, the two joint members


24


and


44


rotate in the same direction when assembled together. Inclined faces


24




a




1


and


44




a




1


of the convex portions


24




a


and


44




a


oppose driving transmission faces


24




a




2


and


44




a




2


, and are formed as inclined faces which guide the convex portions


44




a


and


24




a


of the joint members


44


and


24


to intermesh. It is to be noted that the inclination angle of the inclined faces


24




a




1


and the inclination angle of the inclined faces


44




a




1


are equal to each other.




As shown in

FIG. 3

, a casing


42




a


of the oil recovery pump


42


is formed integrally with a front cover


25


of the engine


20


, and a casing


41




a


of the oil supply pump


41


is secured to the casing


42




a


of the oil recovery pump


42


by a plurality of bolts


46


, only one being shown in FIG.


3


. An opposing wall


41




b


of the oil supply pump


41


next to the oil recovery pump


42


forms part of the casing of the oil recovery pump


42


, and forms a barrier between the oil supply pump


41


and the oil recovery pump


42


.




The front cover


25


is secured to a front portion of the engine


20


by a plurality of bolts


25




a


, only one being shown in FIG.


3


. When the front cover


25


is secured to the front portion of the engine


20


, the joint member


44


of the pump shaft


43


and the joint member


24


of the crankshaft


21


are coupled to each other within the front cover


25


.




As shown in

FIGS. 1

,


2


and


4


, an oil tank


50


is disposed above and very close to the oil pump


40


. An oil filter


60


is provided on an upper face of the oil tank


50


. As shown in

FIG. 4

, the oil tank


50


has an oil storage portion


51


, a supply path


52


formed above the oil storage portion


51


for supplying oil to the oil filter


60


, and a discharge path


53


for discharging oil from the oil filter


60


.




The oil storage portion


51


has an oil entrance


51




i


and an oil exit


51




o


formed therein. Exit


51




o


is connected to an inlet port


41




i


of the oil supply pump


41


by a pipe


71


. A delivery port


41




o


of the oil supply pump


41


is connected to the supply path


52


to the oil filter


60


by a pipe


72


. The discharge path


53


from the oil filter


60


is connected to a main gallery


26


of the engine


20


by a pipe


73


. Oil supplied from the main gallery


26


to various portions of the engine is recovered into an oil pan


27


. The oil pan


27


is connected to an inlet port


42




i


of the oil recovery pump


42


by a pipe


74


, and a discharge port


42




o


of the oil recovery pump


42


is connected to the entrance


51




i


of the oil tank


50


. Accordingly, a general circulation route of oil is from the oil tank


50


, to the oil supply pump


41


, then to the oil filter


60


, then to the main gallery


26


of the engine


20


, then to various portions of the engine, then to the oil pan


27


of the engine


20


, then to the oil recovery pump


42


, and finally back to the oil tank


50


.




Oil routes from the main gallery


26


of the engine


20


include four routes. The first route is a route wherein oil lubricates a bearing portion


26




a


of the crankshaft


21


from the main gallery


26


, then lubricates a crank pin, a connecting rod and a connection portion


26




b


, and is jetted to the back P


1


of a piston P, whereafter it returns to the oil pan


27


. The second route is a route wherein oil lubricates a bearing portion


26




d


of a balancer from the main gallery


26


through a sub gallery


26




c


, and then returns to the oil pan


27


. The third route is a route wherein oil flows from the main gallery


26


to a camshaft internal flow path


26




e


to lubricate a cam mechanism for valve motion, and then returns to the oil pan


27


. The fourth route is a route wherein oil flows from the main gallery


26


to the turbo charger to lubricate a shaft portion


26




f


of the turbo charger, and returns to the oil pan


27


. A relief valve


28


is provided for the main gallery


26


.




With the engine and oil pump arrangement having such a configuration as described above, several operation and effects are obtained. Since the oil pump


40


is disposed on an extension line of the crankshaft


21


, and the joint member


24


provided at an end portion of the crankshaft


21


and the joint member


44


provided at an end portion of the pump shaft


43


are coupled to each other on the same axial line, the requirement for a conventionally required transmission gear is eliminated. In the present invention, the oil pump


40


can be driven with a simple structure, and the number of parts can be reduced. Further, since the two joint members


24


and


44


are coupled to each other within the cover


25


of the engine


20


, the space S (refer to

FIG. 3

) for coupling the crankshaft


21


and the pump shaft


43


to each other may be small.




Because the two joint members


24


and


44


are coupled to each other within the cover


25


of the engine


20


in this manner and cannot be visually observed, there is the possibility that the coupling operation may be difficult. However, since the joining portions of the two joint members


24


and


44


are formed with concave and convex portions, and since the faces


24




a




1


and


44




a




1


of the convex portions


24




a


and


44




a


which oppose the driving transmission faces of the convex portions


24




a


and


44




a


are formed as inclined faces


24




a




1


and


44




a




1


which guide the convex portions


44




a


and


24




a


to intermesh, even if the coupling portions of the two joint members


24


and


44


are within the cover


25


and cannot be visually observed, the coupling operation can be readily performed.




In the present invention, the oil pump


40


can be driven with a simple structure, and the number of parts can be reduced. In addition, while the space S for coupling the crankshaft


21


and the pump shaft


23


may be small, the coupling operation of the two joint members


24


and


44


can be readily performed.




Since the joint member


24


of the crankshaft


21


side is secured by being fastened together with the ACG rotor


23


which is provided at an end portion of the crankshaft


21


, the ACG rotor


23


and the joint member


24


can be provided efficiently in a small space with a small number of parts at an end portion of the crankshaft


21


. Because the oil tank


50


connected to the oil pump


40


is disposed above and very close to the oil pump


40


, the space above the oil pump


40


can be utilized efficiently, and members around the engine


20


can be compactly arranged. Also, since the pipes


71


,


72


and


75


for connecting the oil pump


40


and the oil tank


50


to each other can be made short, oil can be circulated efficiently.




Since the oil supply pump


41


and the oil recovery pump


42


of the oil pump


40


are driven to rotate by the same shaft


43


, the engine can be compact when compared with an engine configuration wherein the oil pumps


2


and


3


are disposed on individual shafts


2




a


and


3




a


and driven to rotate by transmission systems, as in the conventional engine with an oil pump shown in FIG.


10


.




Where the oil supply pump


41


and the oil recovery pump


42


are driven to rotate by the common shaft


43


as in the present invention, although the length of the pump


40


in its axial line direction becomes comparatively large, the space above the oil pump


40


can be utilized effectively by disposing the oil tank


50


above and very close to the oil pump


40


, and members around the engine can be compactly configured. In addition, not only it is possible to make the pipes


71


,


72


and


75


for connecting the oil pump


40


and the oil tank


50


to each other short to augment the circulation efficiency of oil, but it is also possible to concentrate the pipes


71


and


72


for the oil supply pump


41


and the pipe


75


for the oil recovery pump


42


.




The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.



Claims
  • 1. An engine with an oil pump comprising:an oil pump disposed on an extension line of a crankshaft of said engine; a first joint member provided at an end portion of said crankshaft; and a second joint member provided at an end portion of a shaft of said oil pump, said joint members being coupled to each other on the same axial line within a cover of said engine, wherein the joining portions of both of said first and second joint members are formed with concave and convex portions, and faces of said convex portions are formed as linearly inclined faces for guiding said convex portions of the opposing joint members together, said inclined faces of said convex portions of said first joint member being positioned against said inclined faces of said convex portions of said second joint member.
  • 2. The engine with an oil pump according to claim 1, wherein said first joint member is secured together with a rotor provided at said end portion of said crankshaft.
  • 3. The engine with an oil pump according to claim 1, wherein an oil tank connected to said oil pump is disposed above and very close to said oil pump.
  • 4. The engine with an oil pump according to claim 2, wherein an oil tank connected to said oil pump is disposed above and very close to said oil pump.
  • 5. The engine with an oil pump according to claim 1, wherein said oil pump includes an oil supply pump and an oil recovery pump which are both driven to rotate by said shaft.
  • 6. The engine with an oil pump according to claim 2, wherein said oil pump includes an oil supply pump and an oil recovery pump which are both driven to rotate by said shaft.
  • 7. The engine with an oil pump according to claim 3, wherein said oil pump includes an oil supply pump and an oil recovery pump which are both driven to rotate by said shaft.
  • 8. The engine with an oil pump according to claim 1, wherein each of said convex portions further includes a vertical face opposing said linearly inclined face, said vertical faces of said convex portions of said first joint member being positioned against said vertical faces of said convex portions of said second joint member.
  • 9. An engine with an oil pump comprising:an engine having a crankshaft; an oil pump having a pump shaft, said pump shaft and said crankshaft being rotatable about a same axis of rotation; and a coupling device for connecting said crankshaft to said pump shaft, said coupling device including: a first joint member attached to an end of said crankshaft; and a second joint member attached to an end of said pump shaft, said first joint member and said second joint member each including a plurality of convex portions disposed along a circular line, each of said convex portions including a linearly inclined face and an opposing vertical face, said inclined faces of said convex portions of said first joint member being positioned against said inclined faces of said convex portions of said second joint member, and said vertical faces of said convex portions of said first joint member being positioned against said vertical faces of said convex portions of said second joint member, wherein said first joint member is engaged with said second joint member to transmit rotation from said crankshaft to said pump shaft.
  • 10. The engine with an oil pump according to claim 9, wherein said first joint member includes a plurality of concave portions alternately disposed with said convex portions along a circular line, and said second joint member includes a plurality of convex portions alternately disposed with said convex portions along a circular line.
  • 11. The engine with an oil pump according to claim 10, wherein said convex portions of said first joint member are received in respective ones of said concave portions of said second joint member, and said convex portions of said second joint member are received in respective ones of said concave portions of said first joint member.
  • 12. The engine with an oil pump according to claim 10, wherein said convex portions of said first joint member each include a top face located between said inclined face and said vertical face, and said convex portions of said second joint member each include a top face located between said inclined face and said vertical face.
  • 13. The engine with an oil pump according to claim 11, wherein said inclined faces of said convex portions of said first joint member are positioned next to said inclined faces of said convex portions of said second joint member when said convex portions of said first joint member are received in respective ones of said concave portions of said second joint member.
  • 14. The engine with an oil pump according to claim 13, wherein said vertical faces of said convex portions of said first joint member are positioned next to said vertical faces of said convex portions of said second joint member when said convex portions of said first joint member are received in respective ones of said concave portions of said second joint member.
  • 15. The engine with an oil pump according to claim 9, wherein said engine includes a front cover, and said oil pump includes a casing integrally formed with said front cover.
  • 16. The engine with an oil pump according to claim 9, wherein said oil pump includes an oil supply pump and an oil recovery pump, and said pump shaft is common to both said oil supply pump and said oil recovery pump.
  • 17. The engine with an oil pump according to claim 16, wherein said oil supply pump includes a casing having a wall member, said wall member forming a barrier between said oil supply pump and said oil recovery pump.
  • 18. The engine with an oil pump according to claim 16, wherein said oil supply pump includes a casing having a wall member, said wall member also forming part of a casing of said oil recovery pump.
  • 19. The engine with an oil pump according to claim 9, wherein said oil pump includes an oil supply pump and an oil recovery pump, and said pump shaft is common to both said oil supply pump and said oil recovery pump, said engine includes a front cover, said oil recovery pump includes a casing integrally formed with said front cover, said oil supply pump includes a casing having a wall member, said wall member forming a barrier between said oil supply pump and said oil recovery pump.
  • 20. The engine with an oil pump according to claim 9, further comprising an oil tank located directly above said oil pump, and at least one pipe fluidly interconnecting said oil tank with said oil pump.
  • 21. An engine with an oil pump comprising:an oil pump disposed on an extension line of a crankshaft of said engine; a first joint member provided at an end portion of said crankshaft; and a second joint member provided at an end portion of a shaft of said oil pump, said joint members being coupled to each other on the same axial line within a cover of said engine, wherein the joining portions of both of said joint members are formed with concave and convex portions, and faces of said convex portions which oppose driving transmission faces of said convex portions are formed as inclined faces for guiding said convex portions of the opposing joint member together, and wherein said oil pump includes an oil supply pump and an oil recovery pump which are both driven to rotate by said crankshaft.
  • 22. An engine with an oil pump comprising:an engine having a crankshaft; an oil pump having a pump shaft, said pump shaft and said crankshaft being rotatable about a same axis of rotation; and a coupling device for connecting said crankshaft to said pump shaft, said coupling device including: a first joint member attached to an end of said crankshaft; and a second joint member attached to an end of said pump shaft, wherein said first joint member is engaged with said second joint member to transmit rotation from said crankshaft to said pump shaft, and wherein said oil pump includes an oil supply pump and an oil recovery pump, and said pump shaft is common to both said oil supply pump and said oil recovery pump.
  • 23. The engine with an oil pump according to claim 22, wherein said oil supply pump includes a casing having a wall member, said wall member forming a barrier between said oil supply pump and said oil recovery pump.
  • 24. The engine with an oil pump according to claim 22, wherein said oil supply pump includes a casing having a wall member, said wall member also forming part of a casing of said oil recovery pump.
  • 25. The engine with an oil pump according to claim 22, wherein said oil pump includes an oil supply pump and an oil recovery pump, and said pump shaft is common to both said oil supply pump and said oil recovery pump.
  • 26. The engine with an oil pump according to claim 25, wherein said engine includes a front cover, said oil recovery pump includes a casing integrally formed with said front cover, and said oil supply pump includes a casing having a wall member forming a barrier between said oil supply pump and said oil recovery pump.
Priority Claims (1)
Number Date Country Kind
11-329464 Nov 1999 JP
US Referenced Citations (4)
Number Name Date Kind
4680987 Morimoto Jul 1987 A
5720638 Hale Feb 1998 A
5730657 Olgren Mar 1998 A
5755606 Takahashi et al. May 1998 A
Foreign Referenced Citations (2)
Number Date Country
0 376 901 Jul 1990 IT
A9301286 Nov 1997 JP