JP3052002B2 - Oil tank structure of dry sump lubricated internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry sump having a scavenge pump for returning oil retained in an oil reservoir at the bottom of a crankcase to an oil tank, and a feed pump for supplying the oil in the oil tank to each lubrication unit. The present invention relates to an oil tank structure for a lubricated internal combustion engine.

[0002]

2. Description of the Related Art A conventional dry sump lubricated internal combustion engine is disclosed in Japanese Utility Model Laid-Open Publication No. 63-126508, and its oil tank is provided separately outside the internal combustion engine.

[0003]

However, when an oil tank is provided outside as in the above-mentioned conventional dry sump lubrication type internal combustion engine, a pipe connecting the oil tank to a scavenge pump and a feed pump provided on the internal combustion engine side is provided. This necessitates an increase in manufacturing cost and weight, and also has a problem that the layout of the oil tank is subject to various restrictions.

The present invention has been made in view of the above circumstances, and has as its object to provide a compact oil tank structure of a dry sump lubricated internal combustion engine that has a simple structure, does not require piping, and is compact.

[0005]

According to the present invention, there is provided a scavenge pump for returning oil retained in an oil reservoir at a bottom of a crankcase to an oil tank, and supplying the oil in the oil tank to each lubrication unit. In a dry sump lubricated internal combustion engine oil tank structure provided with a feed pump for supplying oil ,
The main shaft of the mission is the crankshaft.
The main shaft is arranged so as to be parallel to and above the shaft, and protrudes from one side wall of the crankcase of the main shaft.
The clutch is provided at one end which has issued the clutch and before
Crankcase cover that covers one side wall of the crankcase
And between the opposing surface of the crankcase and one side wall.
Directly forming the oil tank located below the switch
To separate the inside of the oil tank and between the clutches
The partition wall, the one side wall of the crankcase and the crankcase
The first feature is that it is formed over the cover .

Further, the present invention provides, in addition to the first feature described above,
A second feature is that a primary ratio of the crankshaft and the main shaft is set to 1.

Further, the present invention provides, in addition to the first feature described above,
A third feature is that an oil passage leading from the scavenge pump to the oil tank is formed on the mating surface of the crankcase and the crankcase cover. Further, the present invention provides an oil for a dry sump lubricated internal combustion engine comprising: a scavenge pump for returning oil retained in an oil reservoir at a bottom portion of a crankcase to an oil tank; and a feed pump for supplying oil in the oil tank to each lubricating unit. In the tank structure, the mission is placed in the crankcase,
Main shaft is aligned parallel to the crankshaft
And the crankshaft of the main shaft
The clutch is provided at one end which is protruded from the over scan one side wall, its
Clutch and a crank covering one side wall of the crankcase
Surface of the crankcase cover and one side wall of the crankcase
The oil tank is directly formed between the oil tanks.
There becomes a portrait me along to the side space of the outer periphery of the clutch
As shown in FIG.
And a partition wall that separates the clutch
A fourth feature is that it is formed over one side wall and the crankcase cover .

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 6 show a first embodiment of the present invention. FIG. 1 is an overall side view of an internal combustion engine provided with the lubricating device, FIG. 2 is an enlarged view of a main part of FIG. 3 is an enlarged view of a main part of FIG. 1, FIG. 4 is a sectional view taken along line 4-4 of FIG. 1, and FIG.
FIG. 6 is a sectional view taken along line 5-6 of FIG. 3.

A single-cylinder four-cycle internal combustion engine E for a motorcycle includes a crankcase 3 divided into a right half 1 of a crankcase and a left half 2 of a crankcase. The block 4, the cylinder head 5, and the head cover 6 are joined. Side wall 11 of right half ₁ of crankcase and left half 2 of crankcase
Between the side walls 2 ₁ of the crankshaft 8 is supported through a ball bearing 7, the balancer shaft 10 in front of the crankshaft 8 via a ball bearing 9
Is supported. A main shaft 11 and a counter shaft 12 of the transmission M are supported above and behind the crankshaft 8 via ball bearings 13 and 14, respectively, and a shift fork shaft 15 and a shift drum are provided below the main shaft 11. 16 are supported.

As is apparent from FIG. 5, an output gear 17 provided on the crankshaft 8 meshes with a balancer gear 18 which is keyed to the right end of the balancer shaft 10, thereby fixing the front primary balancer fixed to the left end of the balancer shaft 10. 19 is rotated at the same speed as the crankshaft 8. On the other hand, the balancer drive gear 20 provided on the crank shaft 8 meshes with the front secondary balancer 21 and the balancer gear 21 ₁ integral, relatively rotatably carried through a needle bearing in a central portion of the balancer shaft 10, whereby said The front secondary balancer 21 is connected to the crankshaft 8
It is driven to rotate at double speed.

A left cover 22 covering the left half 2 of the crankcase 3 and a cooling water pump cover 23 further covering the outside.
A cooling water pump 24 that is connected to and driven by the left end of the balancer shaft 10 is housed in the inside.

As is apparent from FIGS. 4 and 5,
Left and right side walls 1 of link case 1₁, 2 ₁Classes supported by
The link shaft 8 has a pair of balance weights 8 at the center.
₁The balance weight part 8₁Join
Large end of connecting rod 26 on crank pin 25
Is connected. At the left end of the crankshaft 8
A well-known AC generator 27 also serving as an eel is mounted.

Right cover 2 covering right half 1 of the crankcase
A pump drive shaft 29 coaxially connected to the right end of the crankshaft 8 is rotatably supported on the crankshaft 8. A trochoid scavenge pump 30 and a feed pump 31 are supported on the pump drive shaft 29. The scavenge pump 30 includes an outer rotor 32 rotatably housed in a recess formed in the inner surface of the right cover 28, and an inner rotor 33 coupled to the pump drive shaft 29 and meshing eccentrically with the outer rotor 32. , 33 are closed by a cover plate 34.

The feed pump 31 includes an outer rotor 35 rotatably housed in a recess formed on the outer surface of the right cover 28, and an inner rotor 36 coupled to the pump drive shaft 29 and meshing eccentrically with the outer rotor 35.
The outer surfaces of both rotors 35 and 36 are covered with an oil pump cover 37.
Is closed by A filter chamber 39 containing a filter 38 is formed in the right cover 28 so as to be located above the feed pump 31, and the opening of the filter chamber 39 is covered by an oil pump cover 37. The capacity of the scavenge pump 30 is set to be larger than the capacity of the feed pump 31 so that the oil level of the oil staying at the bottom of the crankcase 3 does not rise.

As is apparent from FIG. 6, the output gear 17 of the crankshaft 8 is connected to the main shaft 1 of the transmission M.
The transmission of the driving force between the crankshaft 8 and the main shaft 11 is controlled by meshing with the input gear 41 of the clutch 40 provided at the right end of the clutch shaft 1 and turning the clutch 40 on and off. Clutch 40 is accommodated in the clutch housing portion 28 ₁ formed so as to protrude from the right cover 28 to the outside. In order for the input gear 41 of the clutch 40 to have a rear primary balancer, the number of teeth of the output gear 17 of the crankshaft 8 and the number of teeth of the input gear 41 of the clutch 40 are the same, and the primary gear of the crankshaft 8 and the main shaft 11 of the transmission M is used. The ratio is set to 1. Thereby, the diameter of the clutch 40 is reduced, and the capacity of the oil tank 51 described later is sufficiently ensured.

The main shaft 11 and the counter shaft 12 of the transmission M are provided with a plurality of gear trains G _{1 to} G ₅ for selectively establishing a desired shift speed. Change spindle shaft 42 which is rotated by the shift change pedal (not shown) is connected to the shift drum 16 via the change mechanism 43, the shift fork shaft 15 in the cam groove 16 ₁ to 16 ₃ provided on the outer periphery of the shift drum 16 three shift forks 44 _{1-44 3} on the proximal end that is rotatably supported slidably engages the. And shift fork 44 _{1-44 3}
Desired gear position by selectively engaging a gear train G ₁ ~G ₅ of the one is established by the tip. An idler gear 45 meshing with the balancer drive gear 20 of the crankshaft 8 is rotatably supported on the main shaft 11 via a needle bearing. The idler gear 45 is rotatably supported on the counter shaft 12 via a needle bearing. Rear secondary balancer 46
When the balancer gear 46 ₁ of the integral is engaged. Thus, the rear secondary balancer 46 is driven to rotate at twice the speed of the crankshaft 8.

As is apparent from FIGS. 3 and 4, an oil sump 47 is formed at the bottom of the crankcase 3 for retaining oil lubricating various parts of the internal combustion engine E, and a strainer 48 is provided therein. You. At the rear right side of the crankcase 3, the crank with the left and right sides are partitioned by the case right half first sidewall 1 ₁ and the right cover 28, the crankcase right halves 1 and the right cover 28 surrounds the rear portion of the clutch 40 The front side is partitioned by a partition wall 49 reaching the bottom, and the right half 1 of the crankcase and the right cover 2
8 an oil tank 51 whose rear side is partitioned by a rear wall 50
Is formed. The side wall 1 ₁ of the crankcase right halves 1 defining the left side of the oil tank 51, oil tank 5
A convex portion 511 bulging toward the left half portion 2 of the crankcase is formed in order to increase the volume of ₁ .

As shown in FIG. 1 and FIG.
Side wall 1 of right half 1₁And left side of crankcase 2
Wall 2₁Between them, the balance weight of the crankshaft 8
Part 8 ₁Along the outer circumference of the shift drum 16
Thus, a pair of arc-shaped ribs 52 and 53 are formed. Soshi
The oil tank 51 is located in the right half 1 of the crankcase.₁To
Through hole 1 formed_TwoAre formed below the ribs 52, 53.
Auxiliary oil chamber 54, left half of crankcase 2₁Formed in
Through hole 2_TwoCover in which the AC generator 27 is stored via
22 so that the oil tank 51
The oil level is kept constant.

As shown in FIG. 2, it is formed an oil passage L ₁ extending forward and upward in the convex portion 28 ₂ projecting from the right cover 28,
Headspace strainer 48 of the oil reservoir 47 via the oil passage L ₁ is communicated with the suction port of the scavenge pump 30. As shown in FIGS. 3 and 6, the oil passage L ₂ connecting the discharge port of the scavenge pump 30 is right cover 2
8 extend rearward, and the partition wall 4 of the clutch 40
Connect the arcuate oil passage L ₃ formed in the mating surface of the crankcase right half 1 and the right cover 28 constituting the 9, connected to the oil return port 51 ₂ formed on the upper end of the oil tank 51 at its distal end . The arcuate oil passage L ₃ branches laterally, the oil passage L ₄ was formed in the shift fork shaft 15 therefrom, crankcase left half 2 Notohidari cover 2
Through an oil passage L ₅ which is formed in two mating surfaces communicating with the oil passage L ₆ formed inside the main shaft 11. The oil passage L ₃ of the arcuate branches laterally at another location, communicates with the oil passage L ₇ formed inside the counter shaft 12.

As shown in FIG. 2, the oil passage formed in parallel with the oil passage L ₁ on the convex portion 28 ₂ projecting from the right cover 28 L
₈ communicates with the suction port of the feed pump 31. FIG.
As shown in the discharge port of the feed pump 31 reaches the oil passage L ₉ formed in the oil pump cover 37 in the filter chamber 39, where after passing through the filter 38 from the radially outside to the inside, forming the oil pump cover 37 branches to upward oil passage L ₁₀ and down the oil passage L ₁₁ was. Oil passage L down the oil passage L ₁₁ is passing through the interior of the pump drive shaft 29
_12, reaches the crank pin 25 via the oil passage L ₁₃ formed inside the crank shaft 8. On the other hand, the upward oil passage L
₁₀ crankcase right half 1 via the oil passage L ₁₄ for branching the interior of the crank case right half 1 in the horizontal direction and the right cover 2
8 mating surface to reach the cylinder head 5 via the oil passage L ₁₅ and not shown oil passage rearward formed in its mating face
Lubricating the valve mechanism etc. provided in Forward oil passage L ₁₆ formed in the mating surface can also be the balancer shaft 10 via the oil passage L ₁₇ formed in the right cover 28 as shown in FIG. 5
Communicating with the oil passage L ₁₈ formed inside the.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

When the crankshaft 8 rotates by the operation of the internal combustion engine E, the pump drive shaft 29 connected to the right end of the crankshaft 8 rotates, and the scavenge pump 3
0 and the feed pump 31 are simultaneously driven.

Outer rotor 32 of scavenge pump 30
The oil retained in an oil sump 47 formed at the bottom of the crankcase 3 by the rotation of the inner rotor 33 is sucked and passes through the strainer 48, and passes through an oil passage L ₁ formed in the right cover 28 through the suction port of the scavenge pump 30. Inhaled. Most of the oil that is pumped from the discharge port to the oil passage L ₂ of the scavenge pump 30 is returned to the oil tank 51 via the oil passage L ₃ and the oil return port 51 _2. On the other hand, a part of the oil reaches the oil passage L ₆ formed inside the main shaft 11 from the oil passage L ₃ via the oil passage L ₄ and the oil passage L _5, gear train G ₁ ~ which is supported on the outer periphery thereof G ₅
Lubricate. At the same time the oil supplied to the oil passage L ₃ branches the oil passage L ₇ formed inside the counter shaft 12, to lubricate the gear train G ₁ ~G ₅ that supports at its outer periphery.

On the other hand, the oil sucked from the oil tank 51 by the rotation of the outer rotor 35 and inner rotor 36 of the feed pump 31 is drawn from the oil passage L ₈ formed in the right cover 28 to the suction port of the feed pump 31 . From the discharge port of the feed pump 31 to the oil passage L ₉
Passes through the filter 38 via the oil passage L ₁₁ ,
Oil passages L _12, to lubricate the crank pin 25 via the oil passage L _13. A part of the oil that has passed through the filter 38 passes through the oil passage L ₁₀ , the oil passage L ₁₄ , and the oil passage L ₁₅ ,
As well as lubricating the valve operating mechanism or the like provided in the oil passage L ₁₆ and the oil passage L ₁₇ reaches the oil passage L ₁₈ formed inside of the balancer shaft 10 via a front secondary balancer 21 is supported on the outer periphery thereof Lubricate. As described above, one end of the main shaft 11 in the mission M inside the crankcase 3
A clutch 40, the clutch 40 and the crank
Case one side wall 1 ₁ crankcase cover 28 for covering the
If, OY between the facing surfaces of the crankcase side wall 1 ₁
Rutanku 51 was directly formed, so that the oil tank 51 is elongated I along the side space of the outer periphery of the click <br/> latch 40
Then, it extends along the side space and
Partition 49 between the clutch and clutch 40
Over the scan one side wall 1 ₁ and the crank case cover 49
Has formed. Therefore, the piping required when the oil tank 51 is provided outside the crankcase 3 can be omitted. As a result, the structure of the oil tank 51 and its piping system is simplified, and the manufacturing cost, weight, and space are reduced. Savings are possible. Also, the dead space in the crankcase 3 is effectively used to increase the capacity of the oil tank, and the oil tank 51 is formed to reduce the dead space and reduce the amount of oil circulating inside the crankcase 3. Can be. The Also OIL is rotated together is dragged on the outer periphery of the clutch 40,
As much as possible to prevent by the partition walls 49 extending I along the outer periphery of the clutch 40, it is possible to reduce the power loss due to the drag motion of the oil, yet oil oil from the oil tank 51 bottom for the same amount of oil The surface height is increased, and the air bleeding performance of the oil can be improved. Also clan
Single the click case cover 28 to the crankcase side wall 1 ₁
The oil tank between the two opposing surfaces.
To Rutotomoni so as to form a link 51 directly, Oiruta
The partition wall 49 is formed in the link 51 and between the clutch 40.
The oil tank 51 and the partition
The formation of the wall 49 is very easy and the crankcase
And a protective cover against the one side wall 1 ₁ and the clutch 40
Connect the crankcase cover 28 to the oil tank 51
Can also be used as a tank wall, further simplifying the structure and extending
Cost savings.

FIGS. 7 and 8 show a second embodiment of the present invention. FIG. 7 is an overall side view of the internal combustion engine corresponding to FIG. 1, and FIG. 8 is a sectional view corresponding to FIG. .

[0027] This example have a feature in which projects the projecting portion 51 ₃ formed in the rear of the oil tank 51 to further crankcase left half 2 side than the convex portion 51 ₁ of the first embodiment doing. Thus, the capacity of the oil tank 51 can be further increased by effectively utilizing the dead space of the left half portion 2 of the crankcase.

Further, the oil tank 51 of this embodiment has a baffle rib 55 extending forward from the right half portion 1 of the crankcase and the rear wall 50 of the right cover 28.
Thus, the fluctuation of the oil level in the oil tank 51 is regulated. The baffle rib 55 may be inclined so that the tip is upward so that bubbles entrained in the oil can be separated.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, and various small designs may be made without departing from the present invention described in the appended claims. It is possible to make changes.

For example, in the embodiment, the scavenge pump 30
Although the main shaft 11 and the counter shaft 12 are lubricated by a part of the oil returned to the oil tank 51 from the oil, the scavenge pump 30 may simply return the oil to the oil tank 51. Further, the scavenge pump 30 and the feed pump 31 are not limited to the trochoid pump, and include an internal gear pump having a partition member between an internal gear and an external gear, or an external gear pump in which two external gears are combined. Other types of pumps can be used. The present invention is also applicable to a multi-cylinder internal combustion engine.

[0031]

As described above, according to the first aspect of the present invention, a clutch is provided at one end of a main shaft provided above a crankshaft, and a dead space below the clutch inside the crankcase is provided. Since the oil tank is formed in the oil tank, piping required when the oil tank is provided outside the crankcase can be omitted. As a result, the structure of the oil tank and its piping system is simplified, and the production cost, weight, and space can be reduced. Also, attach the crankcase cover to the crankcase
Simply connect to the side wall, and
The oil tank can be formed directly,
Can be formed to separate the inside of the tank and between the clutches.
The formation of the oil tank and the partition wall
Is very easy, and the crankcase
Cover that also serves as a protective cover for the switch
Can also be used for the oil tank wall.
The structure of the layers is simplified, and the cost is reduced.

According to a second feature of the present invention, the primary ratio between the crankshaft and the main shaft is set to one.
By doing so, the diameter of the clutch can be reduced, so that a sufficient space for forming the oil tank can be secured inside the crankcase.

According to the third aspect of the present invention, since the oil passage leading from the scavenge pump to the oil tank is formed on the mating surface of the crankcase and the crankcase cover, the oil passage can be provided without providing any special piping. Can be formed. According to a fourth aspect of the present invention, Clan
The mission within the case, and the main
The raft is arranged in parallel with the crankshaft,
The main shaft projects from one side wall of the crankcase
The clutch is provided at one end which is its clutch and Kura
A crankcase cover that covers one side wall of the crankcase;
The oil tank is placed directly between the rank case and one side wall.
Formed, so that the oil tank is vertically I along the side space of the outer periphery of the clutch, and extends along the side direction space
The partition that separates the inside of the oil tank and between the clutches
Since the <br/> formed over the crankcase one side wall and the crankcase cover, not only omit a pipe that is required when providing the oil tank to the crankcase exterior, Oh <br/> yl clutch from being rotated together is dragged on the outer periphery, as much as possible prevented by the partition wall extending I along the outer periphery of the clutch, it is possible to reduce the power loss caused by the accompanying rotation of the oil. In addition, the capacity of the oil tank can be increased by effectively utilizing the dead space in the crankcase, and the dead space in the crankcase can be reduced to reduce the amount of oil circulating inside the crankcase. Further, since the oil tank is formed vertically long, the height of the oil level from the bottom surface of the oil tank is increased for the same amount of oil, and the air bleeding performance of the oil is improved. Ma
The crankcase cover on one side of the crankcase
Just by joining, the oil tank
Can be formed directly in the oil tank.
And the partition wall between the clutches can be formed.
It is very easy to form the oil tank and the partition wall.
And one side wall of the crankcase and the clutch
Replace the crankcase cover, which also serves as
The structure can be further simplified because it can also be used as the tank wall of the tank.
And eventually cost savings.

[Brief description of the drawings]

FIG. 1 is an overall side view of an internal combustion engine showing a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG. 1;

FIG. 3 is an enlarged view of a main part of FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 1;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 1;

FIG. 6 is a sectional view taken along line 6-6 in FIG. 3;

FIG. 7 is an overall side view of an internal combustion engine corresponding to FIG. 1 showing a second embodiment of the present invention;

FIG. 8 is a sectional view corresponding to FIG. 6;

[Explanation of symbols]

3. Crankcase 8. Crankshaft 11. Main shaft 28. Right cover (crankcase cover) 30. Scavenge pump 31. Feed pump 47. Oil reservoir 51. Oil tank L _3.・ Oil passage M ・ ・ ・ Mission

Claims (4)

(57) [Claims] 1. A scavenge pump (30) for returning oil retained in an oil reservoir (47) at the bottom of a crankcase (3) to an oil tank (51);
1) In the oil tank structure of a dry sump lubricated internal combustion engine provided with a feed pump (31) for supplying the oil in each lubrication unit, a transmission (M) is provided in the crankcase (3) .
Mission (M) main shaft (11)
Above the shaft (8) and parallel to it
And the crank of the main shaft (11)
The clutch (40) provided at one end which projects from the case one side wall (1 _1), the clutch (40) and the clan
Crankcase cover to cover one side wall (1 ₁ )
(28) and one side wall (1 ₁ ) of the crankcase
Between the surfaces, the clutch (40)
The oil tank (51) is formed directly and the oil tank
(51) Partition for partitioning inside and between the clutch (40)
Wall (49), the crankcase side wall (1 ₁₎ and click
An oil tank structure for a dry sump lubricated internal combustion engine, wherein the oil tank structure is formed over a rank case cover (28) . 2. An oil tank structure for a dry sump lubricated internal combustion engine according to claim 1, wherein a primary ratio of said crankshaft (8) and said main shaft (11) is one. 3. An oil passage (L ₃ ) leading from the scavenge pump (30) to an oil tank (51) is formed on a mating surface of a crankcase (3) and a crankcase cover (28). An oil tank structure for a dry sump lubricated internal combustion engine according to claim 1. 4. A scavenge pump (30) for returning oil retained in an oil reservoir (47) at the bottom of a crankcase (3) to an oil tank (51);
1) In the oil tank structure of a dry sump lubricated internal combustion engine provided with a feed pump (31) for supplying the oil in each lubrication unit, a transmission (M) is provided in the crankcase (3) .
Mission (M) main shaft (11)
Disposed so as to align parallel to the Kushafuto (8), said main shaft (11), the crankcase side wall (1
₁ ) Provide a clutch (40) at one end protruding from
The clutch (40) and one side wall of the crankcase
(1 ₁₎ and the crankcase cover (28) covering a該Ku
The oil is placed between the rank case and one side wall (1 ₁ ).
The tank (51) is formed directly and the oil tank (5
1) As is <br/> Vertical I along the side space of the outer periphery of the clutch (40), said Oy extending along the said side lateral space
Between the clutch (40) and the clutch (40).
Cut the partition wall (49) into one side wall (1) of the crankcase.
₁ ) and the crankcase cover (28)
An oil tank structure for a dry sump lubricated internal combustion engine.