JP2001090519A - Vertical engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase, by simple structure, the capacity of an oil pan coupled to an oil pan coupling face formed on an underface of an engine block, in a vertical engine supporting the crankshaft to direct vertically. SOLUTION: The oil pan coupling face 115 formed on the underface of the engine block 11 supported to direct the crankshaft 15 vertically is extended to the lower side of a cylinder head 12 over a prolonged line L to the lower side of a cylinder head coupling face 114 formed in a rear face of the engine block 11, and an area of the oil pan coupling face 115 is thereby increased without interfering with the cylinder head coupling face 114 to increase the capacity of the oil pan 411 coupled to the coupling face 115. Since the both coupling face 114, 115 are not continued to each other, the generation possibility of any obstacle as to sealing for the coupling faces 114, 115 is precluded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical engine having a crankshaft supported vertically.

[0002]

2. Description of the Related Art In general, in a vertical engine in which a crankshaft is supported on an engine block in a vertical direction, a cylinder head connecting surface for connecting a cylinder head and an oil pan connecting surface for connecting an oil pan are provided. Formed on the engine block. 64-2
Japanese Patent Application Laid-Open No. 5-10070 discloses that an end of an oil pan connecting surface is located in front of an extension line extending downward from a cylinder head connecting surface.
Japanese Patent Application Laid-Open No. 7-133, discloses an oil pan connecting surface formed over the lower surface of an engine block and the lower surface of a cylinder head.

[0003]

However, in the construction disclosed in Japanese Utility Model Laid-Open Publication No. 64-24415, the edge of the oil pan connection surface is located in front of an extension line extending downward from the cylinder head connection surface. Therefore, there is a problem that the area of the oil pan connection surface is insufficient and the capacity of the oil pan is limited. Further, in the structure described in Japanese Patent Application Laid-Open No. H8-100707, since the oil pan connection surface is formed over the lower surface of the engine block and the lower surface of the cylinder head, a gasket between the engine block and the cylinder head is also included. Therefore, there is a problem that a flat joint surface must be obtained by co-machining, which causes an increase in processing cost. In addition, special processing equipment is required that can process hard gaskets.

Further, in the case where an exhaust passage, a cooling water passage, a drain passage, and the like extending vertically are provided in an oil pan constituent member integrally having an oil pan, the openings of these passages interfere with the openings of the oil pan. In addition, not only the position of the opening of the oil pan is limited, but also the capacity of the oil pan is limited. In particular, when the cooling water passage is formed on both sides of the cylinder bore, it is necessary to form a water dividing portion for distributing the cooling water to the cooling water passages on both sides of the cylinder bore in the oil pan constituent member. The position and capacity of the opening are further restricted.

[0005] The present invention has been made in view of the above circumstances, and in a vertical engine in which a crankshaft is supported vertically, a capacity of an oil pan coupled to an oil pan coupling surface formed on a lower surface of an engine block. Is to be increased with a simple structure.

[0006]

According to the first aspect of the present invention, there is provided an engine block for integrally supporting a cylinder bore and supporting a crankshaft in a vertical direction. A vertical engine comprising: a cylinder head coupled to a cylinder head coupling surface formed in a vertical direction on a block; and an oil pan coupled to an oil pan coupling surface formed horizontally in an engine block. Has been proposed to extend to below the cylinder head beyond an extension line below the cylinder head coupling surface.

According to the above construction, the oil pan connecting surface formed on the engine block extends below the cylinder head beyond the extension line below the cylinder head connecting surface formed on the engine block. The area of the oil pan coupling surface can be increased without interfering with the coupling surface, and the capacity of the oil pan coupled to the oil pan coupling surface can be increased. Moreover, since the cylinder head connecting surface and the oil pan connecting surface are not continuous with each other, there is no possibility that the sealing of the connecting surfaces will be hindered.

According to the invention described in claim 2,
In addition to the configuration of the first aspect, there is proposed a vertical engine, wherein an oil pan component member integrally including the oil pan integrally includes a peripheral wall of a main exhaust passage.

According to the above construction, since the peripheral wall of the main exhaust passage is formed integrally with the oil pan constituent member, the main exhaust passage can be moved to the cylinder head side regardless of the mating surface of the engine block and the cylinder head. As a result, the opening area of the oil pan can be increased to increase the capacity.

According to the third aspect of the present invention,
In addition to the configuration of claim 1 or 2, a vertical engine is proposed, wherein the oil pan constituent member integrally has a peripheral wall of a cooling water passage.

According to the above construction, since the peripheral wall of the cooling water passage is formed integrally with the oil pan constituent member, the cooling water passage can be moved to the cylinder head side regardless of the mating surface of the engine block and the cylinder head. As a result, the opening area of the oil pan can be increased to increase the capacity.

[0012] Incidentally, the oil case binding surface 11 ₅ Example corresponds to the oil pan connecting surface of the present invention.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 12 show a first embodiment of the present invention. FIG. 1 is an overall side view of an outboard motor, FIG. 2 is an enlarged sectional view of a main part of FIG. 1, and FIG. FIG. 4 is a sectional view taken along a line 3-3 in FIG.
5, FIG. 5 is a view taken along line 5-5 in FIG. 4, FIG. 6 is a view taken in direction 6 in FIG. 5, FIG. 7 is a view taken in direction 7 in FIG. 6, and FIG. 9 is a view taken in the direction of the arrow 9 in FIG. 4, FIG. 10 is a view taken in the direction of the arrow 10-10 in FIG. 4, and FIG.
FIG. 12 is a cross-sectional view taken along line 1-11 of FIG.

As shown in FIGS. 1-3, the upper part of the outboard motor O
The two-cylinder four-cycle engine E mounted on the
Case 11₁And two upper and lower cylinder bores 11_Two, 1
1_TwoEngine block 11 integrally provided with
A cylinder head 12 connected to a block 11;
A head cover 13 coupled to the
The two series formed in the engine block 11
Daboa 11_Two, 11 _TwoTwo slidable fittings
Ston 14,14 supported by engine block 11
Connecting rods 16 and 1 are connected to the crankshaft 15
6 are connected.

A generator 17 and a recoil starter 18 are coaxially provided at an axial end of a crankshaft 15 projecting upward from the engine block 11. A camshaft 20 is supported in a valve operating chamber 19 defined between the cylinder head 12 and the head cover 13, and a cam pulley 21 provided at an upper end thereof and a crank pulley 22 provided above the crankshaft 15 form a timing belt 23.
Connected by An intake valve 26 and an exhaust valve 27 for opening and closing an intake port 24 and an exhaust port 25 formed in the cylinder head 12, respectively, are connected to the camshaft 20 via an intake rocker arm 28 and an exhaust rocker arm 29, respectively. An air cleaner 30, a throttle valve 31, and a carburetor 32 disposed on the right side of the engine E are connected to the intake port 24.

[0017] axis of the crankshaft 15 is disposed vertically, and cylinder bore 11 _2, 11 ₂ of the axes,
Crankcase 11 ₁ side cylinder head 12 side facing forward is disposed in the longitudinal direction to face backward. The crank phases of the two pistons 14, 14 are the same,
The ignition timing is shifted by 360 °. The crankshaft 15 is provided with counterweights 15 ₁ ... Having a balance ratio of 100% against the reciprocating mass of the pistons 14, 14.

An upper surface of an oil case 41 as an oil pan constituent member is connected to a lower surface of the engine E having the above structure.
The upper surface of the extension case 42 is connected to the lower surface of the oil case 41, and the extension case 4
The lower surface of the gear case 43 is coupled to the lower surface of the gear case 2. The outer periphery of the oil case 41 and the outer periphery of the lower half of the engine E are
Covered by an under cover 44 coupled to the upper end of the extension case 42, the under cover 44
The upper half of the engine E is covered by the engine cover 45 connected to the upper end of the engine E.

As is apparent from FIG.
Numeral ₁ is integrally provided with an oil pan 41 _{1, in} which a suction pipe 47 having an oil strainer 46 is housed. An exhaust passage forming member 48 is connected to the rear surface of the oil case 41.
Inside of the exhaust expansion chamber 49 is defined through the bulkhead 42 _1.

The exhaust gas exiting from the exhaust port 25 is
Main exhaust passage 11 formed inside gin block 11_ThreeOr
The first main exhaust passage e formed in the oil case 41₁Flow
(See arrow a in FIG. 10), and from there the communication port e_TwoThrough
The upper exhaust formed above the exhaust passage forming member 48
Expansion chamber e_ThreeFlows into. Upper exhaust expansion chamber e_ThreeExhaust gas inside
Part of the connection_FourThrough the oil case 41
The second main exhaust passage e formed_FiveAnd then from there
Exhaust expansion chamber 49 of gear case 43, gear case 43
Through the hollow portion around the propeller shaft 53
Released into external water. On the other hand, the exhaust passage forming member 48
Upper exhaust expansion chamber e_ThreeSome of the exhaust gas in the
₆Through the lower portion of the exhaust passage forming member 48
Part exhaust expansion chamber e₇And from there exhaust outlet e₈Through
Is discharged into the air. Lower exhaust expansion chamber e₇At the bottom of
Is the main exhaust passage of the oil case 41
e _FiveDrain hole e for discharging water₉Is formed.

As is apparent from FIGS. 2 and 10, the cooling water pumped by a cooling water pump (not shown) is supplied to cooling water passages w ₁ and w ₂ formed on the mating surface of the engine block 11 and the oil case 41. , From which it branches into two and is supplied to the engine block 11 and the cylinder head 12 (see arrow b in FIG. 10). Cooling water that has cooled the engine block 11 and cylinder head 12 is supplied to the cooling water passage w ₃ formed on the lower surface of the engine block 11 (see the arrow c in FIG. 10), the cooling water passage w formed therefrom in the oil case 41 After passing through ₄ , it is discharged into the extension case 42.

The drive shaft 50 connected to the lower end of the crankshaft 15 extends downward through the drive shaft chamber 51 formed in the extension case 42 through the oil case 41, and has a propeller 52 at the rear end. 43 is connected to a front end of a propeller shaft 53 supported in the front-rear direction via a forward-reverse switching mechanism 54.

The mounting bracket 55 for detachably mounting the outboard motor O to the hull S includes a mounting bracket body 56 having an inverted J-shape and a push screw 57 screwed to the mounting bracket body 56. A front end of a swing arm 59 is pivotally supported on the mounting bracket body 56 via a fulcrum pin 58, and a pipe-shaped swivel case 60 is integrally connected to a rear end of the swing arm 59. Mounting bracket body 5
A number of pin holes 56 ₁ ... is provided at the 6, pin holes 56 ₁ either of the pin holes formed in locking plate 60 ₁ fixed to the swivel case 60 mounting bracket body 56
.. Can be adjusted by adjusting the tilt angle of the outboard motor O around the fulcrum pin 58.

A swivel shaft 62 rotatably fitted inside the swivel case 60 has a mount arm 63 and a mount block 64 at its upper and lower ends, respectively.
Is provided. The upper mount arm 63 is elastically connected to the oil case 41 via a pair of left and right upper mounts 65, 65, and the lower mount block 64 is elastically connected to the extension case 42 via a lower mount 66. You. A steering handle 67 is fixed to the front end of the oil case 41. By operating the steering handle 67 left and right, the oil case 41 is swung right and left around the swivel shaft 62 to move the outboard motor O. Can be steered.

Next, a structure for supporting the crankshaft 15 on the engine block 11 will be described with reference to FIGS.

Crankcase 11₁If you have
In the meantime, two cylinder bores 11_Two, 11_TwoWas formed
The engine block 11 has a cylinder head 1
Cylinder head connecting surface 11 to which 2 is connected_FourWith
The oil case 41 is connected to the lower surface of the oil case 41.
Face 11_FiveThe upper cover 71 is connected to the upper surface.
Upper cover connecting surface 11 to be combined₆With its front
To crankcase 11 ₁Blow-by gas in the intake system
Breather device to which the refluxing breather device 72 is coupled
Coupling surface 11₇Is provided. Breather device coupling surface 11₇Is d
Crankcase 11 of engine block 11₁Shape on the bottom of
The center of the crankcase 11₁Within
Opening 11 communicating with the space₈(See FIG. 7) is formed
You.

FIG. 4 and is apparent from FIG. 9, the upper cover 71 is coupled to the upper cover coupling surface 11 ₆ of the upper surface of the engine block 11, eight bolt holes 71
It is fastened to the engine block 11 by bolts passing through ₁ ... a. Arm 71 ₃ ... from central bearing hole 71 ₂ formed in three of the upper cover 71 extends radially outward, the bolt holes 71 ₄ ... in which is formed on the arms 71 ₃ ... tip of the generator A starter cover 73 (see FIG. 2) covering the recoil starter 17 and the recoil starter 18 is fixed.

The journal 15 ₂ of the lower crank shaft 15 located towards the vertical direction, the bearing metal 74 attached to the bearing hole 11 ₉ of the lower wall of the engine block 11
It is supported on, and the upper side of the journal 15 ₃ of the crank shaft 15 is supported by the bearing metal 75 attached to the bearing hole 71 ₂ of the upper cover 71 (see FIG. 4). Thus, the lower journal 15 of the crankshaft 15
₂ and upper journal 15 ₃ to engine block 1
1 and the upper cover 71, bolts 76 are attached to the large ends of the upper and lower connecting rods 16, 16.
The bearing caps 16 ₁ , 16 ₁ attached by…
Opposite the opening 11 ₈ which is formed in the engine block 11 and the crankcase 11 ₁ integral (see FIGS. 4 and 7).

Thus, the crankcase 11₁Together
The engine block 11 has two cylinder bores 1
1_Two, 11_TwoAnd the lower jar of the crankshaft 15
Null 15_TwoBearing hole 11 for supporting₉Is formed,
Those cylinder bores 11_Two, 11_TwoAnd bearing hole 11₉
Is an element that is one member without straddling two members.
It is formed only on the gin block 11. As a result,
Daboa 11_Two, 11 _TwoAnd bearing hole 11₉Processing
At this time, in a state where the two members are connected, the two members are connected.
So-called co-processing is no longer necessary,
Not only reduces the man-hours required for joining and separating components
In addition, it can contribute to improvement of processing accuracy. As well
The journal 15 on the upper side of the crankshaft 15_ThreeTo
Bearing hole 71 to support_TwoIs also a single member
Since it is formed in the bar 71, the bearing hole 71_TwoWhen processing
Eliminates the need for machining, reducing machining man-hours and improving machining accuracy
Can contribute to the top. And engine block 1
1 and the upper cover 71 without replacing the set
Parts can be interchanged independently, making parts interchangeable
Enhanced.

Assembly around the crankshaft 15 of the engine E is performed in the following procedure. In lower while supporting the journal 15 ₂ of the crank shaft 15 in the bearing hole 11 ₉ of the engine block 11, while a bearing hole 71 ₂ of the upper cover 71 is fitted to the upper side of the journal 15 ₃ of the crank shaft 15, the combining the upper cover 71 to the upper cover coupling surface 11 ₆ of the engine block 11. Subsequently, advance the piston 14, 14 having attached connecting rods 16 and 16 are fitted from the cylinder head coupling surface 11 ₄ side cylinder bores 11 _2, 11 _2, the crankshaft 15 a large end of the connecting rod 16 and 16 Of the bearing caps 16 ₁ , 16 ₁ with bolts 76.

[0031] In this case, as it is clear from FIGS. 4 and 7, since the large end of the connecting rod 16, 16 is opposed to the front surface of the opening 11 ₈ in the engine block 11,
Bearing cap 16 through the opening 11 _{8 1,} 1
6 ₁ of the fastening work can be easily performed. Therefore, it is not necessary to secure an extra space in the crankcase 11 ₁ in order to perform the work of fastening the bearing caps 16 ₁ , 16 ₁ , and the assembling work of the crank shaft 15 can be performed while the engine block 11 is downsized. can do.

As is apparent from FIGS. 4 and 6, by projecting a rear lower portion of the engine block 11 at the rear, horizontal oil case binding surface 11 ₅ for coupling the oil case 41 in the engine block 11, an engine block It extends rearward beyond the extension line L of the vertical below the cylinder head coupling surface 11 ₄ to couple the cylinder head 12 to 11. Thereby, the oil case connection surface 11
₅ area was enlarged to the maximum, the oil pan 41 ₁ volume of the oil case 41 coupled thereto can be sufficiently secured. Moreover, since the oil case binding surface 11 ₅ and the cylinder head coupling surface 11 ₄ not continuous to each other, there is no risk of interfering with the sealing of the oil case binding surface 11 ₅ of the seal and the cylinder head coupling surface 11 _4.

The oil pan 41 of the oil case 41
First in the vicinity of _1, the second main exhaust passage e _1, e ₅ and the cooling water passage w _1, w ₄ is formed in the vertical direction, the effect of projecting the lower rearwardly after the engine block 11, Oil case connection surface 11 _{5 of} engine block 11
The first and second main exhaust passages e ₁ , e ₅ and the cooling water passages w ₁ , w ₅ do not interfere with the opening of the oil pan 41 ₁ because the area of the mating surface of the oil case 41 connected to the oil case 41 also increases. It becomes possible to arrange ₄ . As a result, it is possible to capacity increase by increasing the opening area of the oil pan 41 _1.

As is apparent from FIGS. 4 and 8, the breather device 72 which is mounted so as to close the opening 11 ₈ in the engine block 11, the inner member 77 and outer member 78 attached via a seal member 79 And is attached to the engine block 11 with four bolts 80. The inner member 77 is formed an opening 77 ₁ that communicates with the crank chamber, the reed valve 81 is an inner member 7 for opening and closing the opening 77 ₁
7 is provided on the inner surface. The inner surface of the outer member 78 is formed projecting wall 78 ₁ which protrudes toward the inner member 77, a labyrinth 82 by the projecting wall 78 ₁
Is formed. Also on the outer surface of the outer member 78, communicating holes 78 ₂ which communicates via a breather pipe (not shown) the interior space of the labyrinth 82 into the intake system of the engine E is formed.

Next, the structure of the lubrication system of the engine E is shown in FIG.
6 and 9 to 12 will be described.

As is apparent from FIG. 4, a pump housing 86 is fixed to the lower surface of the cylinder head 12, and
The lower part of the camshaft 20 is supported by the pump housing 86. The oil pump 87 driven by the lower end of the camshaft 20 is housed between a lower surface of the pump housing 86 and a pump cover 88 fixed thereto.

FIG. 4 and FIGS.
An oil pan integrally provided in the oil case 41
41₁Seat 11 of the engine block 11 to be the ceiling
_TenThen, the oil passage forming member 89 is fixed by bolts 90, 90.
Is determined. The oil pan 4 has an oil pan 4
1₁To which the suction pipe 47 housed inside is connected.
Claws 89₁And the remaining oil discharged by the oil pump 87.
Oil pan 41 ₁With the relief valve 91
Provided.

[0038] In Thus, the oil in the oil pan 41 in _1,
An oil strainer 46, the suction pipe 47, the joint 89 _1, the oil passage p ₁ (Fig. 4, see FIGS. 5 and 10) which passes through the engine block 11 and cylinder head 12 in the horizontal direction and the oil pump 87 through the Inhaled. The oil discharged from the oil pump 87 passes through an oil passage p ₂ (see FIGS. 5 and 10) which is formed parallel to the oil passage p ₁ and passes through the engine block 11 and the cylinder head 12 in the horizontal direction. Oil chamber r formed between block 11 and oil passage forming member 89
₁ (see FIGS. 10 to 12), and from there, to an oil filter 92 provided on the right side of the engine block 11 through an oil passage p ₃ (see FIG. 10) formed in the engine block 11. The oil chamber r _1, the relief valve 91 faces.

The oil filtered by the oil filter 92 is supplied to an oil passage p ₄ (FIG. 10) formed in the engine block 11.
10), an oil chamber r ₂ formed between the engine block 11 and the oil passage forming member 89 (see FIGS. 4 and 10).
Is supplied to the reference), from there via the oil passage p ₅ formed in the engine block 11 (see FIGS. 4 and 10), it is supplied to the journal 15 ₂ of the lower bearing metal 74 and the crankshaft 15. Supply of oil to the lower side of the crank pin of the crankshaft 15 is performed via a formed inside the oil passage of the crankshaft 15 from the journal 15 ₂ of the lower (not shown).

On the other hand, part of the oil supplied to the oil chamber r ₂ is supplied to an oil passage p ₆ (see FIGS. 6 and 10) extending vertically through the engine block 11. Oil passage p ₆
An oil passage p ₇ (see FIGS. 5 and 6) branched in the horizontal direction from the vicinity of the upper end of the oil passage is supplied to the valve operating chamber 19 through the engine block 11 and the cylinder head 12 and housed therein. Lubricate. The oil that has lubricated the valve mechanism is supplied from an oil passage p extending horizontally through the cylinder head 12 and the engine block 11 from the lower end of the valve chamber 19.
₈ (see FIGS. 5 and 10), the oil pan 41 ₁
Is returned to.

The oil supplied to the oil passage p ₆ extending upward in the engine block 11 (see FIG. 6) passes through oil passages p ₉ and p ₁₀ formed in the upper cover 71 (see FIGS. 4 and 9). Bearing metal 75 and crankshaft 15
Is the supply to the upper side of the journal 15 _3. Supply of oil to the upper crank pin of the crankshaft 15 is performed via a formed inside the oil passage of the crankshaft 15 from the upper side of the journal 15 ₃ (not shown).

[0042] Thus, the supply of oil to the upper journal 15 ₃ of the crank shaft 15 farthest from the oil pump 87, without using formed inside the oil passage of the crankshaft 15, the engine block 11 is performed through the formed oil passage p ₆ (see FIG. 6) and the oil passage p ₉ formed in the upper cover 71, p _10, reliably supplying a sufficient amount of oil to the upper side of the journal 15 ₃ In addition to enabling lubrication, it is possible to greatly simplify the structure of the oil passage.

[0043] As is apparent from FIG. 4, since the oil passage p ₁₀ of the upper cover 71 is inclined obliquely downward toward the bearing hole 71 ₂ side, drilling the oil passage p ₁₀ from the bearing hole 71 ₂ side It is possible to constitute the blind hole formed by the above, and the blind plug is not required, so that the number of processing steps and the number of parts are reduced. This is because, if When the oil passage p ₁₀ was constituted by a through hole penetrating from the outer surface of the upper cover 71 to the bearing hole 71 _2, required is generated for closing the open end of the outer surface side at a blank plug.

The gathered oil in the crankcase 11 ₁ from respective lubricated parts of the engine E, the engine block 11
Is returned to the oil pan 41 ₁ through the opening ₁₁ 11 of the oil case binding surface 11 _5, 11 ₁₂ (see FIG. 10).

FIGS. 13 and 14 show a second embodiment of the present invention. FIG. 13 is a rear view of an engine block and an oil case, and FIG. 14 is an enlarged sectional view taken along line 14-14 of FIG.

The second embodiment is different from the first embodiment in the structure of the exhaust system.
Exhaust from the exhaust port 25 which is different from the first embodiment
The gas is the main exhaust gas formed inside the engine block 11.
Passage 11_ThreeThe first main exhaust formed in the oil case 41 from
Passage e₁To the communication port e_TwoExhaust through
An upper exhaust expansion chamber e formed above the passage forming member 48 _Three
Flows into. Upper exhaust expansion chamber e_ThreeExhaust gas inside is a communication port
e_Four, The second main exhaust formed in the oil case 41
Passage e_FiveTo the extension case 4
The exhaust gas is discharged to the second exhaust expansion chamber 49.

Exhaust expansion chamber of extension case 42
Sub exhaust passage e extending upward from _TenIs the second main exhaust
Passage e_FiveIs formed parallel to the left side of the
Road e _TenIs the communication hole e₁₁Through the oil case 41 and the drain
First auxiliary exhaust expansion chamber e formed between the air passage forming members 48
₁₂Communicate with First auxiliary exhaust expansion chamber e₁₂The oil case
Throttle effect formed between 41 and exhaust passage forming member 48
Narrow part e with fruit₁₃Through the oil case 41 and
Second sub-exhaust expansion chamber formed between exhaust passage forming members 48
e₁₄The second auxiliary exhaust expansion chamber e₁₄Is an exhaust passage type
Exhaust outlet e provided on the rear surface of the component 48₈Communicate with So
And the second auxiliary exhaust expansion chamber e₁₄Is the drain hole e₉Through
And the second main exhaust passage e_FiveAnd an exhaust passage forming member
Negative pressure release hole e formed at 48_FifteenThrough the upper exhaust expansion chamber
e_ThreeAnd the first auxiliary exhaust expansion chamber e₁₂Communicate.

[0048] This second embodiment also, by projecting a rear lower portion of the engine block 11 in the rear, because the oil case binding surface 11 ₅ for coupling the oil case 41 in the engine block 11 is increased, first there , the second main exhaust passage e _1, e ₅ and the cooling water passage w _1, w ₄ makes it easy to arrange so as not to interfere with the opening of the oil pan 41 _1, the opening area of the resulting oil pan 41 ₁ It can be increased to increase the capacity.

The embodiments of the present invention have been described above. However, various design changes can be made in the present invention without departing from the gist thereof.

For example, in the embodiment, the vertical engine E of the outboard motor O is illustrated, but the present invention can be applied to a vertical engine for any other use.

[0051]

As described above, according to the first aspect of the present invention, the oil pan connecting surface formed on the engine block extends beyond the downward extension of the cylinder head connecting surface formed on the engine block. Since the oil pan extends below the cylinder head, the area of the oil pan coupling surface can be increased without interfering with the cylinder head coupling surface, and the capacity of the oil pan coupled to the oil pan coupling surface can be increased. Moreover, since the cylinder head connecting surface and the oil pan connecting surface are not continuous with each other, there is no possibility that the sealing of the connecting surfaces will be hindered.

According to the second aspect of the present invention,
Since the peripheral wall of the main exhaust passage is formed integrally with the oil pan constituent member, the main exhaust passage can be moved to the cylinder head side regardless of the mating surface of the engine block and the cylinder head. As a result, the oil pan Can be increased by increasing the opening area.

According to the third aspect of the present invention,
Since the peripheral wall of the cooling water passage is formed integrally with the oil pan constituent member, the cooling water passage can be moved to the cylinder head side regardless of the mating surface of the engine block and the cylinder head. As a result, the oil pan Can be increased by increasing the opening area.

[Brief description of the drawings]

FIG. 1 is an overall side view of an outboard motor.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is an enlarged view of a main part of FIG. 2;

FIG. 5 is a view taken along line 5-5 in FIG. 4;

FIG. 6 is a view in the direction of arrows in FIG. 5;

FIG. 7 is a view in the direction of arrows in FIG. 6;

8 is a sectional view taken along line 8-8 in FIG. 4;

FIG. 9 is a view in the direction of arrows 9 in FIG. 4;

FIG. 10 is a view taken along line 10-10 of FIG. 4;

FIG. 11 is a sectional view taken along line 11-11 of FIG. 10;

FIG. 12 is a view taken along line 12-12 of FIG. 11;

FIG. 13 is a rear view of an engine block and an oil case according to a second embodiment of the present invention.

FIG. 14 is an enlarged sectional view taken along line 14-14 of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Engine block 11 ₂ Cylinder bore 11 ₄ Cylinder head connection surface 11 ₅ Oil case connection surface (oil pan connection surface) 12 Cylinder head 15 Crankshaft 41 Oil case (oil pan constituent member) 41 ₁ Oil pan e ₁ First main exhaust passage (Main exhaust passage) e ₅ Second main exhaust passage (main exhaust passage) w ₁ cooling water passage w ₄ cooling water passage L Extension line below the cylinder head connection surface

Claims (3)

[Claims] Cylinder bore (11)_Two)
Support the crankshaft (15) vertically
An engine block (11), and a vertical cylinder formed on the engine block (11).
Dahead connection surface (11 _Four) Cylinder head coupled to
(12) and oil formed horizontally on the engine block (11)
Pan connection surface (11_FiveOil pan (4)
1₁), The oil pan coupling surface (11)_Five) Is the cylinder head
Do coupling surface (11_FourOver the extension line (L) below
Extending to below the Linda head (12)
Vertical engine. 2. An oil pan constituting member (41) having said oil pan (41 ₁ ) integrally therewith is provided in a main exhaust passage (e ₁ , e).
_{5. The} method according to claim 1, wherein said peripheral wall is integrally formed.
The vertical engine described in 1. 3. The vertical engine according to claim ₁ , wherein the oil pan constituent member (41) integrally has a peripheral wall of a cooling water passage (w ₁ , w ₄ ).