JP3021341B2 - Lubricating oil supply system for 4-cycle outboard motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil supply device for an outboard motor equipped with a four-stroke engine, and more particularly to an improved arrangement of an oil pump for pumping lubricating oil.

[0002]

2. Description of the Related Art Conventionally, a four-stroke engine employs a lubricating oil supply device in which lubricating oil in an oil pan is pumped to a crankshaft bearing, a camshaft bearing and the like by an oil pump. As an arrangement structure of the oil pump in such a lubricating oil supply device, an oil pump is arranged in a crankcase in parallel with a horizontally disposed crankshaft, and a drive gear or a drive chain is rotated by rotation of the crankshaft. It is common to drive the oil pump through the oil pump.

[0003]

In the case of an outboard motor, a two-stroke engine has conventionally been generally used, so that the above-mentioned lubricating oil supply device is not necessary. However, recently, mainly from the viewpoint of exhaust gas purification, 4
The adoption of a cycle engine is being considered. 4
When a cycle engine is adopted as an engine for an outboard motor, the above-described lubricating oil supply device is required.
It is difficult to adopt the arrangement structure of the oil pump employed in the above-described general four-stroke engine. For example, a structure peculiar to an outboard motor, such as a vertically arranged crankshaft and use at sea. Therefore, it is necessary to develop an oil pump arrangement structure according to the type of use.

[0004] The present invention has been made in view of the above circumstances, and provides a lubricating oil supply device having an oil pump arrangement structure corresponding to a structure peculiar to an outboard motor when a four-stroke engine is employed as the outboard motor. It is intended to provide.

[0005]

According to a first aspect of the present invention, a four-stroke engine is disposed vertically so that a crankshaft is substantially vertical when the vehicle is running, and the crankshaft is connected to a crankcase via a plurality of crank journals. The drive shaft is connected to the lower end of the crankshaft to form an output shaft with the drive shaft and the crankshaft, and the drive shaft extends vertically.
In a lubricating oil supply device for a four-stroke outboard motor having a propeller shaft connected to a lower end thereof, an oil pan is disposed below the engine, a flywheel is provided at a lower end of the crankshaft, and the drive shaft is coaxially connected. The drive shaft and the crankshaft form the same linear output shaft, and an oil pump for pumping lubricating oil is attached to a portion of the output shaft between the flywheel and the oil pan, A lubricating oil return passage from a lubricated portion to an oil pan is formed in an outer portion of the flywheel of an exhaust guide forming a wheel chamber that houses the flywheel.

[0006]

[0007]

[0008]

According to a second aspect of the present invention, in the first aspect, a mount member for mounting the outboard motor to the hull is fixed near the oil pan, and the oil pump is provided between the mount member and the fly. It is characterized by being arranged between the wheels.

According to a third aspect of the present invention, in the first or second aspect, the drive shaft is vertically divided in the vicinity of the flywheel, and a rotary body of the oil pump is constituted by a joint for connecting the divided bodies. It is characterized by being.

According to a fourth aspect of the present invention, in any one of the second and third aspects, an exhaust guide for guiding exhaust gas downward is interposed between the cylinder block and the crankcase and the oil pan. A wheel chamber for accommodating the flywheel is formed between the guide and the lower end of the cylinder block and the crankcase, and the oil pump is disposed in the wheel chamber.

[0012]

A fifth aspect of the present invention is characterized in that, in the fourth aspect, the exhaust guide is divided into upper and lower portions, and a part of an oil passage is formed between the divided surfaces.

[0014]

[0015]

[0016]

[0017]

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 21 are views for explaining an outboard motor according to an embodiment of the present invention. FIG. 1 is a left side view, FIGS. 2 to 7 are plan views, and FIG. 8 is a sectional plan view of a crankcase portion. FIG. 9 is a rear view of the intake system, FIG. 10 is a rear view around the cam shaft, FIG. 11 is a left side sectional view of the intake system, and FIG.
13 is a cross-sectional left side view, FIG. 13 is a view taken along the arrow XIII-XIII in FIG.
FIG. 14 is a view for explaining the flow directions of the lubricating oil and the cooling water, and FIGS. 15, 16, and 17 are lines XV-XV and XVI- in FIG.
18 and 19 are cross-sectional left side views near the oil pan, FIG. 20 is a cross-sectional left side view of the exhaust manifold, and FIG. 21 is a cross-sectional rear view of the exhaust manifold.

In FIG. 1, reference numeral 1 denotes an outboard motor. The outboard motor 1 is mounted on a clamp bracket 3 fixed to a stern 2a of a hull 2 via a swivel arm 4 in a vertical direction about a tilt shaft 5 (arrow in FIG. 1). a), and is supported so as to be pivotable about the pivot 6 in the left-right direction (the direction of arrow b in FIG. 2). The outboard motor 1 has an upper case 9 connected to a lower case 8 holding a screw 7 and a forward / reverse switching mechanism 7a, and cowling around an engine 10 mounted on the upper case 9 via an exhaust guide 40. It has a structure surrounded by 11.

Here, the cowling 11 is an injection-molded product made of resin, and the upper cowling 11b is separated from the mating surface 11a.
And a lower cowling 11c. The upper cowling 11b has a box shape in which the mating surface 11a is open. The upper cowling 11b has a die-cutting gradient in which the cross-sectional shape becomes smaller as going upward from the mating surface 11a. A pair of left and right outside air introduction openings 11d is formed near the upper end of the rear wall of the upper cowling 11b. It should be noted that the left and right outside air inlets 11d, 11d may be entirely outside air inlets.

The engine 10 is of a water-cooled, four-cycle, V-type, six-cylinder, vertically mounted crankshaft type. The cylinder block 12 of the engine 10 has a V shape (V bank).
Left and right cylinder portions 12a, 12
b and a common crankcase portion 12 integrally formed so as to connect the bottom portions of the cylinder portions 12a and 12b to each other.
c. Here, as shown in FIG. 7, portions of the left and right cylinder portions 12a and 12b near the head side mating surface of the V bank inner side walls are connected by a cover wall 12g, and the cover wall 12g and the inner side wall are connected to each other. The space surrounded by is a V-bank space A that extends vertically in a tunnel shape.

Each of the cylinder portions 12a and 12b is provided with three sets of cylinders (cylinder bores) 12d. The cylinders of the left and right cylinder portions 12a and 12b are offset in the crankshaft direction and alternately. It is arranged and formed. The crankcase portion 12c has a pair of cylinders 12d, 12d offset by the crankcase cover 17 connected to the front mating surface.
Crank recess 1 forming one crank chamber E with respect to
2e is formed.

Each piston 14 slidably inserted into each cylinder 12d is connected to a crankshaft 16 via a connecting rod 15. The journal portion 16a of the crankshaft 16 has a bearing wall 12f formed in the crankcase portion 12c so as to define a boundary between the crank chambers E, and a bearing cap detachably mounted on the bearing wall 12f. 13 and rotatably supported.

A baffle plate (partition plate) 75 is provided in the crank chamber E. The baffle plate 75 is formed by molding a metal plate having a large number of small holes into substantially the same shape as the crankcase cover 17, and there is a space between the baffle plate 75 and the crankcase cover 17. The space is an ascending passage E ′ for ascending gas containing oil mist.

The upper end of the rising passage E 'communicates with a chain chamber B having an oil separator function to be described later. The lubricating oil that has dropped to the lower end of the crank chamber E falls into the oil pan 41 through an oil return passage indicated by a dashed arrow H in FIG. More specifically, as shown in FIG. 15, the lubricating oil flows along the boundary wall surface between the pump chamber C and the crank chamber E, flows down through the opening I of the upper guide 40a, and into the recess K of the upper guide 40a. Thereafter, it falls into the oil pan 41 through the opening L.

As will be described later, a starter motor 52 is provided in front of the crankcase cover 17.
Are recessed inside the engine, thereby preventing the entire outboard motor from bulging forward. Also, the width of the recess 17d of the ascending passage E 'is narrower than the other portions due to this recess.

The rear facing surface (head side facing surface) of the left and right cylinder portions 12a and 12b of the cylinder block 12 described above.
, Left and right cylinder heads 18a and 18b are mounted and fastened to the cylinder block 12 by head bolts. The rear facing surfaces (cover facing surfaces) of the two cylinder heads 18a, 18b are the left and right head covers 19a, 19b.
b, thereby forming left and right cam chambers F, F extending in the crankshaft direction (vertical direction).

In the combustion recess 18c formed on the block side mating surface of the cylinder heads 18a and 18b, two intake valve openings and exhaust valve openings are formed for each cylinder, and an intake valve 20a for opening and closing each of the openings. The exhaust valve 20b is driven to open and close by a cam nose 21e of the intake camshaft 21a and the exhaust camshaft 21b, respectively.

The intake and exhaust camshafts 21a and 21b are
The cylinder heads 18a, 18b and the head cover 19a,
In the left and right cam chambers F, F formed with the crankshaft 16, two are arranged in parallel with the crankshaft 16. A cam sprocket 32a having a large diameter (twice the crank sprocket) is provided on the upper end of the intake camshaft 21a for the left cylinder portion and the exhaust camshaft 21b for the right cylinder portion.
32b is mounted and fixed by bolts 21c. The two cam sprockets 32a and 32b and the small-diameter crank sprocket 16b formed near the upper end of the crankshaft 16 are connected by a timing chain 33a. The timing chain 33a communicates the cam chambers F, F with the crank chamber E, and is disposed in the chain chamber B located at the upper end of the engine.

Here, as described above, the upper cowling 11b has a cutting draft whose cross-sectional shape becomes smaller toward the upper side.
As shown in the figure, the basic width of the upper cowling 11b is determined based on the width (left and right dimensions in the drawing) of the chain chamber B in which the cam sprockets 32a and 32b are arranged. , The draft is set so that the width becomes wider toward the lower side.

A guide shaft 34 for supporting a guide sprocket 34a is provided in the V bank space A, and the guide sprocket 34a guides the timing chain 33a along the V bank shape. .
The portion between the crank sprocket 16b and the cam sprocket 32b and the portion between the cam sprocket 32b and the guide sprocket 34a of the timing chain 33a are:
It is guided by fixed guide plates 35a and 35b.

Further, the timing chain 33a
The movable tensioner plate 35c is in sliding contact with the portion between the left cam sprocket 32a and the crank sprocket 16b. The rear end of the tension plate 35c is pivotally supported by a pin 35d, and the front portion thereof is pressed by the pressing mechanism 36 toward the center of the engine. Thereby, the tension of the timing chain 33 is adjusted to be always constant.

Each of the above sprockets 16b, 32a, 32
b, 34a, the timing chain 33a, the guide plates 35a, 35b, and the tension plate 35c are formed by the cylinder block 12, the crankcase cover 17,
Cylinder heads 18a, 18b and head cover 19
A chain chamber B in which a chain cover 37 is detachably attached to an upper end opening of a substantially Y-shape in plan view formed by a and 19b.
Is located within.

The intake and exhaust camshafts 21a and 21b of each cylinder are smaller in diameter (1
(Approximately 1/2) of the intermediate sprockets 32c, 32c. The intermediate sprocket 32c is located adjacent to the upper end cam sprockets 32a and 32b with the cam bearing 21d interposed therebetween, that is, located below the cam sprocket 32a and at the highest point.

Here, the crank chamber E and the cam chambers F, F communicate with the chain chamber B. Although not shown, the chain chamber B is provided with an oil separator function of separating a lubricating oil component from engine gas including oil mist introduced into the chamber. This feature
For example, it can be realized by forming a maze structure in the chain chamber B.

On the portion of the chain cover 37 facing the cam sprockets 32a and 32b, a substantially circular bulging portion 37a is formed in a plan view to avoid interference with the sprocket fixing bolt 21c. Have been.
The bulging portion 37a is located at the highest position in the chain chamber B. A discharge hole 37b for discharging gas in the engine is formed in the bulging portion 37a, and each of the discharge holes 37b is connected to a downstream side of a throttle valve 28 of the intake system 22 described later by a discharge hose 37c. .

The discharge hole 37b may be provided in a portion of the chain chamber B between the crankshaft and the camshaft, as shown by a two-dot chain line in FIG.

Each of the cylinder heads 18a, 18b
The intake valve openings are drawn out toward the inside of the V bank toward the rear of the hull by intake ports 18d, 18d, and an intake system 22 is connected to external connection openings of the intake ports 18d, 18d. The intake system 22 includes left and right cylinder sections 12.
Left and right are symmetrical so that the intake pipe lengths to a and 12b are equal. That is, the left and right surge tanks 23a, 23
b is disposed behind the left and right head covers 19a, 19b in parallel with the crankshaft 16, and the left and right surge tanks 23a, 23b and the intake ports 18d, 18d are connected to the intake manifold section 23c and the intake port. It is structured to be connected through an intake plate 24 having a hole 24a, and the intake pipe length is substantially the same for all cylinders.

The intake plate 24 is connected to the intake ports 18d, 18d of the left and right cylinder heads 18a, 18b.
It is a flat plate that is installed between the external connection openings 18d so as to cover the upper surface of the V bank. The intake plate 24 has an intake hole 24a communicating the intake port 18d and the intake manifold portion 23c, and a fuel injection valve 26 is provided on the intake plate 24 from the intake hole 24a through the intake port 18d. It is mounted so as to inject and supply fuel toward the back surface of the valve head of the intake valve 20a.

The left and right surge tanks 23a, 23
b, and the left and right intake manifolds 23c, 23c are integrally cast, and fuel is supplied to the fuel injection valves 26 in a tunnel formed by the left and right intake manifolds 23c, 23c. A fuel supply rail 25 to be supplied is vertically inserted and arranged. At the upper end of the fuel supply rail 25, a regulator 27 for adjusting the fuel pressure is mounted. Here, the fuel supply rail 25 is fixed to a leg portion 24 b erected on the intake plate 24. Therefore, it is possible to assemble the fuel supply rail 25, the intake plate 24, and the fuel injection valves 26 in a separate process in advance. The fuel flows into the supply rail 25 from the lower end thereof, and is discharged through the regulator 27 at the upper end. This makes it possible to easily remove air from the fuel.

The left and right surge tanks 23a, 23a
The left and right intake pipe portions (branch passages) 23d, 23d integrally formed at the upper end portion of 3b merge into one near the upper end of the engine and at the center in the width direction.
3e is facing the hull front side. And the merging pipe portion 23e
Body 28 with built-in throttle valve 28a
Is connected to the throttle body 28 via a bellows hose 29 having flexibility. The opening of the introduction pipe 30 is located at the upper end of the engine, so that the intake air is less likely to receive heat from the engine, and an increase in the intake air temperature is avoided.

The throttle body 28 is fixedly fastened together with the merging pipe 23e to a bracket 24c extending upward from the upper end of the intake plate 24.
The throttle body 28 is located slightly above the upper wall of the cylinder block 12. The bellows hose 29 is provided for improving airtightness at a connection portion between the introduction pipe 30 and the throttle body 28, and for preventing generation of noise due to suction of air from the connection portion. An introduction pipe 30 connected to the upstream side of the hose 29 is supported by a chain cover 37 via a rubber band 30a.

The left and right surge tanks 23a, 23a
A support plate 77 made of metal is provided on the rear surfaces of 3b, and electrical components 78 such as a control box are mounted on the rear surface of the support plate 77. This support plate 77 not only functions as a heat sink for promoting the cooling of the electrical component 78 by releasing the heat generated in the electrical component 78 to the surge tanks 23a and 23b, but also connects the left and right surge tanks 23a and 23b to each other. It also has the function of preventing vibration and noise by increasing the rigidity.

The left and right cylinder heads 18a, 18
The exhaust valve opening b is led out to the outer wall surface (left and right wall surfaces) of the V bank by left and right exhaust ports 18e, 18e.
The left and right exhaust ports 18e, 18e are connected to left and right exhaust systems 38a, 38b formed symmetrically. The exhaust systems 38a and 38b are connected to an exhaust manifold 39 connected to the three exhaust ports 18e, and to the exhaust manifold 39 via an exhaust guide 40 and an exhaust port 41a formed in an oil pan 41. An exhaust pipe 42 and a muffler 65 connected to the exhaust pipe 42 are provided.

The above-mentioned exhaust manifold 39 is shown in FIGS.
As shown in FIG. 1, each of the cylinder portions 12 of the cylinder block 12 is joined while the three exhaust ports 18e are merged.
a, 12b extending downward along the outer wall surface, and extending between the cylinder heads 18a, 18b and the exhaust guide 40 to the inside of the V-bank.
0 exhaust passage 40e.

The exhaust manifold 39 has an integral casting double pipe structure having a water cooling jacket J, and has a structure in which the outer circumference of an inner pipe part 43 through which exhaust gas flows is surrounded by an outer pipe part 44 constituting a water cooling jacket. It has become. The exhaust manifold 39 is provided with a main body portion 39a located on the upper side.
And an elbow-shaped joint portion 39b located on the lower side, and is divided into two parts by a portion which is horizontal between the cylinder heads 18a, 18b and the exhaust guide 40, and both are connected by a rubber joint 45. ing. Since the horizontal portion is divided into two parts as described above, workability when connecting the two parts with the rubber joint 45 can be improved.

The rubber joint 45 includes a rubber inner ring 45 a for connecting the inner pipes 43 to each other, and an outer pipe 44.
The inner ring 45a is fixed to the inner tube portion 43 by a band 45c.

At the time of assembling the main body portion 39a and the joint portion 39b, first, the inner ring 45a is fixed to the inner tube portion 43 by the band 45c while the outer ring 45b is shifted to the broken line position in FIG. 21 in the axial direction. Then, move the outer ring to the normal position. As described above, since the two-part structure and the flexible rubber joint 45 are used for connection, the dimensional error between the external connection opening position of the exhaust port 18e of the cylinder head and the opening position of the exhaust passage 40e of the exhaust guide 40 is provided. And can be easily assembled.

A support bracket 48 is fixed to the upper part of the front wall surface 17a of the crankcase cover 17, and a generator 47 is attached to the support bracket 48 by an output shaft 47.
a is directed upward and parallel to the crankshaft 16. A driven pulley 47b mounted on an output shaft 47a of the generator 47 is connected to a driving pulley 51 mounted on the upper end of the crankshaft 16 by a transmission belt 50. Further, the generator 47 is rotatable about a left bolt 49 with respect to the support bracket 48, thereby absorbing the elongation of the belt 50 and adjusting the tension.

A flange portion 17b is formed in a lower portion of the front wall surface 17a of the crankcase cover 17 so as to bulge toward the front side in an overhang shape.
A starter motor 52 is mounted on 7b with the output gear (pinion gear) 52a facing downward and parallel to the crankshaft 16. The output gear 52a of the starter motor 52 meshes with a ring gear 53a formed on the outer periphery of the flywheel 53. The flywheel 53 is connected and fixed to the lower end of the crankshaft 16.

The reference numeral 52b denotes the starter motor 52
The pinion gear moving motor is mounted on the motor, and raises the pinion gear 52a when the engine starts.

A flange portion 12h is formed on the lower end surface of the cylinder block 12 so as to form a mating surface with the flange portion 17b of the crankcase cover 17.
The exhaust guide 40 is connected to the connection surface. An oil pan 41 and the above-described upper case 9 are connected to a lower mating surface of the exhaust guide 40, and the outer case 9 surrounds the outside of the oil pan 41.

The exhaust guide 40 introduces exhaust gas into the muffler 65 and connects the outboard motor 1 to the hull 2.
The upper guide 40a and the lower guide 40b are vertically divided into two parts. A support arm 82 is fixed to a mount member 81 bolted and fixed to the lower guide 40b, and the support arm 82 is supported by a clamp bracket 3 fixed to the hull 2 side.

The exhaust guide 40 is connected to the vertical wall 4.
Od separates a pump chamber (wheel chamber) C and an oil drop chamber D. Furthermore, the lower guide 40
The rear portion of b extends rearward from the upper guide portion 40a, and a space is formed between the extension portion and the cylinder heads 18a and 18b. An exhaust gas expansion chamber 74 is formed at the rear end of the rear extension. The expansion chamber 74 is a silencing chamber in an idle exhaust system for stabilizing the idling operation by discharging exhaust gas to the atmosphere during the idling operation, and is a lower guide 40b.
Is formed in such a manner that the opening of the concave portion 40h formed by the cover 74a is covered with a lid 74a.

The upper opening of the pump chamber C is closed by flange portions 17a and 12h formed at the lower ends of the cylinder block 12 and the crankcase cover 17, so that water does not enter the pump chamber C. It is a closed space.

The flywheel 53 is connected to the pump chamber C
The flywheel 53 is connected to a drive shaft 54 that transmits engine rotation to the screw 7 via a joint rod 55. The drive shaft 54
The crankshaft 16 and the above-mentioned crankshaft 16 constitute the same linear output shaft. An oil pump 56 for pumping lubricating oil is disposed at a joint rod 55 portion of the drive shaft 54, that is, at a portion between the lowermost journal portion 16a and the oil pan 41 disposed below the journal portion 16a. . The oil pump 56 is configured such that the side wall 40c of the upper guide 40a and the cover member 5
7, an outer ring 58 is fixedly disposed so as to be coaxial with the drive shaft 54, and is eccentrically formed on the outer periphery of the joint rod 55 in the outer ring 58 so as to be integrally formed with the inner ring. This is a trochoid pump configured to rotate 55a. This trochoid pump 56
Is disposed in the closed pump chamber C, thereby preventing water from entering the pump.

The oil pump 56 can be provided below the lowermost journal 16a of the crankshaft 16, and such an oil pump arrangement has a flywheel provided at the upper end of the crankshaft. It is also applicable to other types of engines.

When the pump chamber C is formed in a closed state, there is a concern that the rotation of the flywheel 53 causes an increase in the air temperature and an increase in the internal pressure, or the rotation resistance of the flywheel 53. Therefore, in order to avoid this, the air diffuser 66 is provided so as to communicate the atmosphere with the pump chamber C. Further, in order to avoid intrusion of water from the air diffuser 66, the air diffuser 66 has a shape extending upward and having an upper end bent downward. Further, a drain hose 67 is attached to the pump chamber C so that when water enters, the drain can be drained.

The suction port 56a of the oil pump 56 is connected to the oil pan 41 through a suction passage 60, and the discharge port 56b is mounted on the rear wall of the upper guide 40a of the exhaust guide 40 by a discharge passage 61. The oil filter 62 is connected in communication. The oil filter 62 is disposed by utilizing the above-described space created by extending the lower guide 40b of the exhaust guide 40 backward.

The suction passage 60 is connected to the oil pan 41
And a vertical hole 60b formed in the lower and upper guides 40b, 40a, and a horizontal hole 60c formed between the horizontal wall 40c and the lid member 57. . An oil strainer 83 made of a wire mesh or the like is attached to the suction port of the suction pipe 60a.

The discharge passage 61 is provided with a horizontal hole 61a formed between the horizontal wall 40c and the lid member 57, and with the vertical wall 40c.
d, and a transverse cut 61c crossing the oil drop chamber D. Where U
The bottom portion of the character hole 61b is connected to the upper and lower guides 40a,
It is recessed on the mating surface of 40b. That is, the U-shaped hole 61 can be easily formed by dividing the exhaust guide 40 into upper and lower parts. Reference numeral 82 denotes a relief valve for preventing an abnormal rise in the hydraulic pressure in the discharge passage 61.

The supply path 63 from the outlet of the oil filter 62 is mainly connected to a crankshaft lubrication system for supplying lubricating oil to the journal portion 16a of the crankshaft 16 and the journal and cam sliding surfaces of the camshafts 21a and 21b. And a camshaft lubrication system for supplying lubricating oil, and both lubrication systems are arranged in series.

The crankshaft lubrication system includes the discharge passage 6
1, a vertical cutout 63a extending parallel to the horizontal cutout 61c, a vertical hole 63b extending upward in the vertical wall 40d, and a main gallery portion (crankshaft oil) extending up to the upper end in the V-bank bottom wall of the cylinder block 12. Supply passage) 63c. A branch hole 63d from the main gallery portion 63c to the crank journal portion 16a branches from a higher position than the journal portion 16b, and reaches the journal bearing portion 16d after being inclined obliquely downward. That is, the branch hole 63
d is an oil reservoir.

The camshaft lubrication system comprises a block hole 63e formed in the upper end surface of the cylinder block 12 so as to branch left and right from the upper end of the main gallery portion 63b, and a cam shaft bearing portion. Holes 63 formed in the upper end surfaces of the cylinder heads 18a and 18b so as to communicate with
The block hole 63e and the head hole 63f constitute a camshaft oil supply passage. The head hole 63f communicates with an oil hole 21c formed in the axis of each of the camshafts 21a and 21b.
Communicates with the camshaft bearing and the cam nose sliding surface.

The lubricating oil supplied to the upper end of the oil hole 21c through the block hole 63e and the head hole 63f flows through the oil hole 21c while passing through the supply hole formed at a position corresponding to the camshaft bearing. Through the camshaft bearing,
Lubricate the cam nose sliding surface.

The recovery path 64 for recovering the lubricating oil supplied to each section to the oil pan 41 is configured as follows. The recovery path of the lubricating oil supplied to the crankshaft journal bearing 16d and dropped into each crank chamber E from the gap between the bearing 16d and the journal portion 16a is as follows.
A lateral hole (recovery hole) 64a formed in the crank recess 12e near the main gallery portion 63c (central portion) so as to communicate with the V bank space A, the V bank space A, and a return opening 63g. , And a path passing through the oil drop chamber D of the exhaust guide 40. Each of the crank recesses 12e is formed with a vertical hole 64b (see FIGS. 6, 14) penetratingly formed on an extension of the cylinder axis in plan view.
) Also communicates with the return opening 63g.

The lubricating oil recovery path supplied to the sliding surface between the cam shaft journal portion and the bearing portion or the sliding surface of the cam nose is provided at the lower ends of the cylinder heads 18a and 18b so as to communicate with the bottoms of the cam chambers F and F. A horizontal hole 64c formed in the cylinder axis direction is formed in the cylinder block 12 so as to communicate with the horizontal hole 64c.
A horizontal hole 64d formed in the cylinder axial direction on the head side mating surface of each of the cylinder portions 12a and 12b, a path passing through the opening 63g and the oil falling chamber D.

The cooling water system of the outboard motor 1 is configured as follows. A cooling pipe 68 connected to a discharge port of a cooling water pump (not shown) disposed at the lower end of the drive shaft 54 extends upward between the drive shaft 54 and the muffler 65 to extend the oil. A cooling water passage 69 formed at the bottom of the pan 41 is connected to the cooling water passage 69. The cooling water passage 69 is branched into left and right cylinder portions by branch passages 69a, 69a formed in a V-shape in plan view. The lower and upper guides 41 are connected to the water cooling jacket J of the left and right exhaust manifolds 39 via vertical holes 41b formed in the vertical direction and communication holes 40f formed in the lower guide 40b.

The upper ends of the water cooling jackets J of the respective exhaust manifolds 39 are connected to the lower ends of the water cooling jackets of the left and right cylinder portions 12a and 12b of the cylinder block 12 via the cooling hose 70 and the pressure valve 71. 12i (see FIG. 20). The cooling water supplied to each of the cylinder portions 12a and 12b is supplied to the water cooling jacket of each of the cylinder portions and each of the cylinder heads 18.
a, 18b, through each of the cylinder sections 12
a, 12b reach the upper end of the water-cooled jacket.

The upper end of the water cooling jacket of each cylinder is connected to each return hole 40g of the upper guide 40a via a thermo valve 72 and a return hose 73, and each return hole 40g is connected to the lower guide 40b of the lower guide 40b. Exhaust expansion chamber 40h
18 is connected to the drop hole 74b of the lid 74a of FIG.
Lead to. The cooling water guided to the chamber 41n is supplied to an oil pan 4
The oil pan 41 falls from the opening 41j into the exhaust pipe insertion hole 41h of the oil pan 41 and between the rear part of the oil pan 41 and the upper case 9. Then, the muffler 65 falls down and flows down through the opening 65 a formed between the exhaust pipes 42, 42 in the upper case 9.

As described above, according to the gas exhaust device in the engine of the outboard motor 1, the crankshaft 16, which is disposed vertically,
The crank sprocket 16b of the camshafts 21a and 21b,
A discharge hole 37b is formed in a chain cover 37 which forms the top wall of a chamber located at the highest point in the case of a vertical engine called a chain chamber B which houses a timing chain 33a connecting the cam sprockets 32a and 32b. Since the exhaust hose 37c is connected to the intake system, the gas in the engine can be sucked into the intake system and reliably discharged. In addition, since a discharge hole 37b is formed in a bulging portion 37a which is formed by bulging a part of the chain cover 37 with the cam shaft, the bulging portion 37a functions as a discharge chamber. There is no need to form a dedicated discharge chamber.

In this case, since the chain chamber B communicates with both the crank chamber E and the cam chamber F, the gas including blow-by gas and oil mist in the crank chamber E and the oil mist in the cam chamber F , Rises toward the chain chamber B, and is sucked and discharged from the discharge hole 37b through the discharge hose 37c to the intake path.

Each cylinder part 1 of the chain cover 37
Since the discharge holes are formed in the portions facing the camshafts 2a and 12b, respectively, the cylinder portions 12a and 12a forming the V bank are formed.
The engine gas can be reliably discharged from the cam chamber 12b.

The position at which the discharge hole 37b is formed is not limited to the position facing the cam shaft, but may be any position on the chain cover 37 constituting the top wall of the chain chamber B.

The gas exhaust device in the engine is not limited to the V-type engine, but can be applied to an in-line engine having a single cylinder.

Here, when an internal gas exhaust hole is formed in the chain chamber B as in the internal gas exhaust device, the lubricating oil scattered from the timing chain is discharged to the outside of the engine, and the amount of lubricating oil discharged increases. There are concerns that
In the outboard motor 1, an oil separator function for separating the lubricating oil component in the engine gas is added to the chain chamber B, so that the discharge of the lubricating oil is suppressed.

According to the lubricating oil supply device of the outboard motor 1, the drive shaft 54 connected to the lower end of the crankshaft 16 via the flywheel 53 is disposed below the flywheel 53 and below. The oil pump 56 is mounted coaxially with the oil pan 41 so that the oil pump 56 is directly connected to the crankshaft. For example, the oil pump 56 is arranged parallel to the crankshaft and driven via gears or the like. The structure is extremely simple as compared with the conventional one, and the space for arranging the oil pump is small, so that the downsizing particularly required for the outboard motor can be achieved. Further, since the oil pump 56 is driven at the same rotation speed as the engine rotation speed, it is easy to secure the oil amount and the oil pressure.

The oil pump 56 is connected to the flywheel 5
Since it is arranged between the oil pan 3 and the oil pan 41 and immediately above the oil pan 41, the suction head from the oil pump 56 to the oil level in the oil pan 41 can be small, and this point is also considered. It is easy to secure the oil amount and the oil pressure, and the pump can be downsized.

Further, the drive shaft 54 is vertically divided in the vicinity of the flywheel 53 and the rotary body of the oil pump 56 is provided on the outer peripheral surface of a joint rod (connection joint) 55 which is one of the divided bodies. Since a certain inner rotor 55a is formed, the handling during the processing is easy because the joint rod 55 is short, and the processing operation is easier than the case where the pump rotating body is formed on a single drive shaft. .

In the outboard motor 1, the oil pan 41
The oil pump 56 is disposed between the mount member 81 fixed near the flywheel 53 and the flywheel 53. Therefore, since the support arm 82 extends from the mount member 81 toward the hull, Even if the splash generated in step (1) scatters upward, the support arm (82) hinders the oil pump (56) from being mounted on the mount member. A large-diameter flywheel 53 is provided above the oil pump 56.
Is disposed, so that it becomes a hindrance, so that the splash from above is less likely to be applied to the oil pump 56. Therefore, the entry of water into the oil pump 56 is reliably prevented.

The oil pump 56 is accommodated in the pump chamber (wheel chamber) C formed by the exhaust guide 40, the cylinder block 12 and the crankcase cover 17 to prevent water from entering from outside. Oil pump 5 particularly required for outboard motors used at sea
The function of preventing water from entering the device 6 can be improved.

Further, in the outboard motor 1, the lubricating oil suction passage 60 and the lubricating oil return passage (oil drop hole D) are formed in the exhaust guide 40 as a separate member formed separately from the cylinder block. For example, it is easier to form a passage than when formed in the cylinder block 12. In this case, since the exhaust guide 40 has a vertically divided structure, and a part of the oil passage (the bottom of the U-shaped hole 61b) is formed between the divided surfaces, the formation of the oil passage is further facilitated.

The lubricating oil supply device is not limited to a V-type engine, but can be applied to an in-line engine having a single cylinder.

According to the arrangement of the oil filter of the outboard motor 1, the exhaust guide 40 connected to the lower end of the cylinder block 12 and the crankcase cover 17 forms the discharge passage 61 from the oil pump 56 to the engine. Since the oil filter 62 is attached to the rear wall of the exhaust guide 40, it is possible to arrange the oil filter 62 by utilizing a space formed below the cylinder heads 18a and 18b and behind the rear wall of the exhaust guide in a side view. For example, it is possible to avoid an increase in the width of the outboard motor as compared with a case where an oil filter is arranged on the side wall of the cylinder block, and it is possible to secure the miniaturization particularly required for the outboard motor. In this case, since the oil filter 62 is arranged below the center of the V bank in plan view, the outboard motor width can be more reliably prevented from being increased.

Further, an oil pump 56 is provided in the exhaust guide 40, and a suction passage 60 from the oil pan 41 to the oil pump 56 is provided in the exhaust guide 40.
Further, since the discharge passage 61 from the oil pump 56 to the oil filter 62 is formed, it is possible to avoid a problem that the outboard motor width is increased due to the arrangement of the oil pump.

According to the lubricating oil supply and recovery structure of the outboard motor 1, the oil supply passage from the oil pump 56 disposed between the flywheel 53 and the oil pan 41 to a lubricated portion such as a crankshaft journal is provided. In addition, since the flywheel portions 63b and D of the oil return passage from the lubricated portion to the oil pan 41 are formed so as to pass outside the outer periphery of the flywheel 53 when viewed in the crankshaft direction, especially the lubricating oil falls. In the recovery, the flywheel 53 does not become a resistance, and the recovery of the lubricating oil becomes easy.

A main gallery (crankshaft oil supply passage) 63c for supplying lubricating oil from the oil pump 56 to the crankshaft journal 16a is provided in the bottom wall of the V-bank of the cylinder block 12 substantially in parallel with the crankshaft 16. The V-bank space A formed by connecting the V-bank inner side walls of the cylinder portions 12a and 12b with the connection wall 12g is connected to the oil pan 41 by lubricating oil from the crankshaft journal portion and the camshaft journal portion. Since the return oil return passage is used, in the V-type vertical engine, the relatively unused portions of the V-bank bottom wall and the V-bank space can be used. Therefore, the supply passage and the return passage are formed linearly and with a large diameter. This makes it easy to secure the supply oil amount and the hydraulic pressure, and the recovery resistance is smooth.

Since the branch hole 63d from the main gallery 63c to each journal 16a is formed in an inclined shape with the journal side lowered, the branch hole 63d functions as an oil reservoir. Therefore, when the engine is restarted, the journal portion 16a is lubricated by the lubricating oil in the oil reservoir, and lubricity at the time of starting can be ensured.

Further, a lateral hole 64a (recovery hole) for recovering the lubricating oil from the crankshaft journal portion 16a to the V bank space A (oil return passage) is formed so as to connect the crank chamber E to the V bank space A. The amount of lubricating oil accumulated in the crank chamber can be reduced. In this case, cylinders (cylinder bores) 12d, 12
Since the space d is used, a space for disposing the horizontal hole 64a can be secured.

Further, the camshaft oil supply passages 63e and 63f communicating from the upper end of the main gallery portion (crankshaft oil supply passage) 63c to the bearing portion of the camshaft are formed in a divergent manner. Since the shaft oil supply passages are connected in series, the amount of oil supplied to the crankshaft journal can be increased more than the amount of oil supplied to the camshaft journal, and the required amount of each journal can be easily met.

In the lubricating oil supply / recovery structure, the lubricating oil flows downward from the upper end of the camshaft. Conversely, the lubricating oil flows upward from the lower end of the camshaft. Further, the present invention is not limited to the V-type engine, and is applicable to an in-line engine having only one cylinder.

It is also possible to branch the camshaft oil supply passage from the lower part of the crankshaft oil supply passage instead of the above-described series connection. However, in such a case, there is a fear that the amount of oil supply to the crankshaft journal portion becomes insufficient. There is. When such a configuration is adopted, an orifice for adjusting the oil amount is arranged near the branch portion of the camshaft oil supply passage.

According to the exhaust system of the outboard motor 1, the left,
The upstream end of the exhaust manifold 39 is connected to the outer wall of the V bank of the right cylinder heads 18a and 18b, and the exhaust manifold 39 is connected to the space between the cylinder head and the exhaust guide 40 from outside the cylinder head. Since it extends to the center of the bank and is connected to the exhaust passage 40e of the exhaust guide 40 at the center of the V-bank, the exhaust pipe is arranged in the space below the V-bank which tends to be an empty space in the case of a V-type vertical engine. Outboard motor with a 4-cycle V-type engine,
It is possible to avoid an increase in the width of the outboard motor due to the arrangement of the exhaust pipe, and it is possible to cope with miniaturization particularly required in the case of an outboard motor.

The arrangement of the exhaust pipe in the exhaust system can be applied not only to the V-type engine but also to an in-line type engine.

Further, according to the accessory arrangement structure of the outboard motor 1, when the V-type engine is disposed vertically with the cylinder heads 18a and 18b facing the hull rear side, the V-type engine is Since the auxiliary equipment such as the starter motor 52 and the generator 47 is arranged in the front space G opposite to the bank space, the rearward displacement of the center of gravity due to the cylinder head being located on the rear side of the hull is arranged at the front of the auxiliary equipment. And the weight balance can be improved.

In particular, in the case of a V-type engine, the width of the left and right cylinder heads is widened. Therefore, when accessories are arranged on the side of the engine, the width of the outboard motor is undesirably large. Therefore, arranging the accessories in the front space G is advantageous not only in the weight balance but also in securing the space.

In the outboard motor 1, the weight balance in the hull front-rear direction is obtained by arranging the auxiliary equipment in the front space G, the starter motor 52 is provided at a lower part of the front space G, and the generator 47 is provided at the upper part. , The weight balance in the vertical direction can be obtained. Moreover, in this case, the flywheel 53 having the ring gear 53a at the lower end of the crankshaft, the drive pulley 51 at the upper end, the starter motor 52 at the lower part of the front space G, and the generator 47 at the upper part are arranged. 52 drive gear 5
2a can be directly meshed with the ring gear 53a,
Further, the driving pulley 51 is driven by the driven pulley 47 by the transmission belt 50.
The power transmission mechanism is extremely simple, such as simply connecting to the power transmission mechanism b.

When the turning center line is set forward of the crankshaft in the case of a four-cycle V-type engine, the state of the outboard motor 1 is further rearward heavy. When the accessories are located on the front side of the shaft 16, the accessories are arranged on the front side of the turning center line 6.
The above-described weight balance deviation correcting action is more effective.

The above-described accessory arrangement structure can be applied to not only a V-type engine but also a series-type engine.

According to the valve train of the outboard motor 1, a large-diameter cam sprocket is mounted on the intake camshaft 21a inside the V bank for the left cylinder portion 12a, and the V bank is mounted on the right cylinder portion 12b. Outer exhaust camshaft 21
Since it is mounted on the b, it is possible to suppress an increase in the engine width due to the cam sprocket of the valve train without increasing the V-bank angle more than necessary.

That is, since the cam sprocket has a large diameter, providing cam sprockets on both the intake and exhaust camshafts of each cylinder increases the valve pinching angle and the overall width of the engine. When a cam sprocket is provided only on one cam shaft of each cylinder, if both cylinders are provided outside the V bank, this also increases the engine width. On the other hand, if both cylinders are provided inside the V bank, the V bank is provided. There is a concern that the angle will be larger than necessary. In the present outboard motor 1, when the cam sprocket is provided only on one cam shaft of each cylinder portion, the left cylinder portion 12a is provided on the intake cam shaft 21a inside the V bank.
With respect to the right cylinder portion 12b, cam sprockets 32a and 32b are respectively attached to the exhaust cam shaft 21b outside the V bank.
Since b is provided, each of the above problems can be avoided.

In the outboard motor 1, the large-diameter cam sprocket is disposed outside the V-bank of only one of the cylinders without being mounted on the outside of the V-bank of both cylinders. It does not grow. On the camshaft side where the cam sprocket is not mounted, the cross-sectional dimension of the upper cowling 11b can be reduced smoothly from the mating surface 11a to the upper side without any difficulty. This has the effect of avoiding an increase in size. Incidentally, when the engine width is increased due to the arrangement of the cam sprocket, the size of the mating surface 11a of the upper cowling 11b must be increased accordingly, and the cowling 11 eventually becomes large.

The oil in the cam chamber F is stirred by the intermediate chain 33b while flowing down toward the oil outlet 64c while lubricating the cam bearing and the like. Since the oil that falls by the intermediate sprocket 32c or the intermediate chain 33b is agitated because it is located below the chamber B, the oil is agitated because the cam chain chamber B is located above the intermediate chain 33b. Almost no oil flows through the cam chain chamber B to the crank chamber E, and thus the oil in the cam chamber F can be efficiently collected.

The valve train described above is of course applicable not only to a V-type engine but also to an in-line engine.

According to the intake device of the outboard motor 1, the left and right surge tanks 23a, 23b extending substantially parallel to the crankshaft are provided.
To the head covers 19a of the cylinder portions 12a and 12b,
The left and right surge tanks 23a and 23b are symmetrically arranged along the left and right surge tanks 23a and 23b.
d and 23d to join the merging passage 23e,
The distribution amount of air to each cylinder can be made uniform.

The left and right surge tanks 23a, 23
3b and the intake port of each cylinder are connected by the intake manifold 23c of the same length, so that the left and right surge tanks 23c are connected.
Since the cylinders a and 23b have a large capacity, only the intake manifold having the same length affects the substantial intake pipe length to the intake port 18e of each cylinder. The pipe length can be the same for all cylinders.

Further, the outside opening of the merging passage 23e is connected to the outside air inlet 1 formed in the upper part of the cowling 11.
Since it is located near 1d, that is, at the upper end, air above the cowling that is not affected by heat from the engine or the like can be introduced, and an increase in intake air temperature can be avoided. Also, since the outer opening is located at the highest point, it is possible to prevent water jumping from the sea surface from entering the engine.

The left and right surge tanks 23a, 23a
Since the 3d members are connected to each other by the support plate 77 and the control unit 78 is attached thereto, the engine parts can be arranged using the V bank space.

Further, since the throttle body 28 is mounted on the extension 24c which extends upward from the intake plate 24 on which the fuel injection valve 26 is mounted, a dedicated throttle body mounting bracket is not required, and the throttle body mounting structure can be reduced. Can be simplified.

In the above-mentioned outboard motor 1, the case where a pair of left and right surge tanks is provided has been described. As shown in FIG. 22, a surge tank 90 common to the left and right cylinders is disposed at the center of the V bank. May be set. In this case, the structure becomes simple, for example, the intake manifold section 91 connecting the surge tank 90 and the intake port of each cylinder can be made linear.

According to the cooling structure of the outboard motor 1, the cooling water passage 69 passes through the bottom of the oil pan 41 disposed below the cylinder block 12 and is connected to the cooling jacket J of the exhaust pipe 39. Since the jacket J is connected to the engine cooling jacket K, the oil pan 41 and the exhaust pipe 39 can be formed without providing a separate cooling water path by a simple structure in which the arrangement of the cooling water path to the engine cooling jacket is simply devised. Cooling can be performed.

Further, since the cooling water passage 69 is branched left and right at the bottom of the oil pan 41, and the respective branch water passages 69a, 69a are connected from the exhaust cooling jackets J for the respective cylinder portions to the engine cooling jacket K. By forming an independent cooling system for each cylinder, the cooling balance of each cylinder can be improved.

The cooling system independent thermostat valve 72 is provided at the outlet side of the engine cooling jacket K of each cooling system.
Is provided, independent temperature control can be performed for each cooling system, and the cooling balance of each cylinder can be further improved.

Further, since the cooling water passing through the engine cooling jacket K is configured to fall into the water through the periphery of the oil pan 61 and the muffler 65, the cooling water returning to the water is effectively used. Thus, the oil pan 41 and the muffler 65 can be effectively cooled.

The above cooling structure is applicable not only to the V-type engine but also to an in-line type engine having one cylinder.

According to the oil pan arrangement structure of the outboard motor 1, the exhaust manifolds 39, 39 from the respective cylinder portions 12a, 12b are vertically inserted into the rear portion of the exhaust guide 40 at a predetermined interval in the boat width direction. And the bulging portion 41i of the oil pan 41 is connected to the exhaust manifold 3
Since it is located between 9 and 39, the oil pan volume can be secured by utilizing the dead space generated between the left and right exhaust pipes in the case of a V-type vertical engine.

Since the drain plug 80 is provided at the lower end of the bulging portion 41i and the oil level gauge 79 is inserted from the upper end, waste oil can be drained from the lower portion of the bulging portion 41i disposed in the dead space. In addition, lubrication can be performed from above, and the workability of inspection such as replenishment and replacement of lubricating oil can be improved.

A cooling water return port 41j and an opening 65a for returning cooling water to the periphery of the oil pan 41 and the muffler 65 are provided on both sides of the bulging portion 41i of the exhaust guide 40.
Is provided, the oil pan 41 and the muffler 65 can be cooled by return water using the dead space described above.

Further, since the exhaust expansion chamber 74 of the idle exhaust system is provided at the rear of the exhaust guide 40, a space for disposing the exhaust expansion chamber can be secured by utilizing the dead space. Also, in this case, since the concave portion 40h is formed on the upper surface of the lower guide 40b and the lid 74a is put on the concave portion 40h, the concave portion can be formed by casting, and salt accumulation can be avoided.

According to the lubricating oil supply structure of the outboard motor 1, the lubricating oil is disposed vertically and the crankshaft journal portion 1 at the upper end of the engine is provided.
An oil return passage (V-bank space A, oil drop hole D) for returning the lubricating oil lubricating 6a to the oil pan 41 is formed substantially parallel to the crankshaft 16, and lubricating oil is injected into the upper end of the oil return passage. An oil level gauge 7 having a length reaching the oil pan 41 is formed at the inlet 37e.
Since the 9 'is mounted, the oil inlet and the oil level gauge insertion port are shared, and workability can be improved by the simultaneous opening and closing of the inlet and the level gauge attaching / detaching operation.

The oil return passage is connected to the crankshaft 1
6, the lubricating oil supplied from the injection port 37e immediately falls into the oil pan 41, and the oil level in the oil pan 41 is reduced. The waiting time until it becomes constant is greatly reduced, and the workability can be improved from this point as well.

According to the lubricating oil recovery structure of the outboard motor 1, the crankcase cover 17 and the baffle plate (partition plate) are provided.
75 is defined as an oil mist gas ascending passage E ', and the upper end of the ascending passage E' communicates with a chain chamber B having an oil separator function formed at the upper end of the engine. Oil pan 41 from part
Is formed, the lubricating oil discharged from the crankshaft journal portion 16a is separated from the partition plate 7.
5 falls along the inner surface of the partition 5 and is collected in the oil pan 41, and the oil mist gas rises from the pores of the partition plate 75 through the ascending passage E 'to the chain chamber B, where the oil mist is removed from the air. It is separated, falls along the crankcase cover 17 or the partition plate 75, is collected by the oil pan, and the lubricating oil collection efficiency can be improved.

The lubricating oil supply structure and the lubricating oil recovery structure described above are not limited to the V-type engine, but can be applied to an in-line engine having only one cylinder.

FIG. 23 shows the cam sprockets 32a, 32
This is a modification of the arrangement structure of b, in which both cam sprockets 32a and 32b are attached to intake camshafts 21a and 21a located inside the V bank. As a result, both the left and right cylinder portions 12a and 12b have a small amount of outward protrusion, and the right and left width of the cowling 11 can be reduced.

[0125]

According to the lubricating oil supply device for a four-stroke outboard motor according to the first aspect of the present invention, the oil pump is located below the relatively large-diameter flywheel, and water is applied from above. However, since the flywheel performs a shielding function, it is difficult for water to be applied to the oil pump, which has an effect of preventing water from entering the oil pump.

[0126]

[0127]

[0128]

According to the second aspect of the present invention, the oil pump is disposed between the flywheel and the mount member fixed in the vicinity of the oil pan. Will be covered by the support member extending forward from the mount member,
Even if the splash generated at the lower part of the outboard motor scatters upward, the support member performs the shielding function, so that the oil is hardly applied to the oil pump, and the water can be more reliably prevented from entering the oil pump.

According to the third aspect of the present invention, the drive shaft is vertically divided in the vicinity of the flywheel, and the rotary body of the oil pump is constituted by the joint of the divided body. There is an effect that the handling operation is easy and the machining operation is easier than the case where the pump rotating body is formed on one drive shaft.

According to the fourth aspect of the present invention, since the oil pump is disposed in the wheel chamber formed by the exhaust guide, the cylinder block and the crankcase, the oil pump particularly required for an outboard motor used at sea is used. This has the effect of improving the function of preventing water from entering the water.

According to the fifth aspect of the present invention, since a part of the oil passage is formed between the divided surfaces of the vertically divided exhaust guide, the formation of the oil passage is facilitated.

[0133]

[0134]

[0135]

[0136]

[0137]

[Brief description of the drawings]

FIG. 1 is a left side view of an outboard motor according to an embodiment of the present invention.

FIG. 2 is a plan view of the outboard motor.

FIG. 3 is a plan view of the outboard motor.

FIG. 4 is a plan view of the outboard motor.

FIG. 5 is a plan view of the outboard motor with a chain cover removed.

FIG. 6 is a plan view showing an oil passage at an upper end portion of the outboard motor.

FIG. 7 is a sectional plan view of the outboard motor.

FIG. 8 is a sectional plan view of a starter motor portion of the outboard motor.

FIG. 9 is a partial cross-sectional rear view of an intake system of the outboard motor.

FIG. 10 is a rear view showing the camshaft arrangement of the outboard motor.

FIG. 11 is a sectional left side view of an intake system of the outboard motor.

FIG. 12 is a left side sectional view of the outboard motor.

FIG. 13 is a view taken along line XIII-XIII in FIG. 12;

FIG. 14 is a diagram for explaining the flow of lubricating oil and cooling water of the outboard motor.

15 is a sectional view taken along line XV-XV in FIG.

16 is a sectional view taken along line XVI-XVI of FIG.

FIG. 17 is a view taken along line XVII-XVII in FIG. 12;

FIG. 18 is a sectional left side view of an exhaust guide portion of an exhaust system of the outboard motor.

FIG. 19 is a sectional left side view of an oil pan and a muffler portion of the outboard motor.

FIG. 20 is a sectional left side view of an exhaust manifold portion of an exhaust system of the outboard motor.

FIG. 21 is a sectional rear view of a joint portion of an exhaust system of the outboard motor.

FIG. 22 is a cross-sectional plan view showing a modified example of the surge tank portion of the intake device for the outboard motor.

FIG. 23 is a plan view showing a modification of the arrangement of the cam sprocket of the outboard motor.

[Explanation of symbols]

 10 4 cycle engine 16 Crankshaft 16a Crank journal 17 Crankcase 41 Oil pan 54 Drive shaft, output shaft 56 Oil pump

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-10113 (JP, A) JP-A-7-149290 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01M 1/02 F01M 1/06

Claims (5)

(57) [Claims] 1. A four-stroke engine is disposed vertically so that the crankshaft is substantially vertical when traveling, and the crankshaft is supported by a crankcase via a plurality of crank journals. An output shaft is formed by connecting the drive shaft and the drive shaft and the crankshaft, and the drive shaft is extended in a vertical direction, and a propeller shaft is connected to a lower end thereof.
In a lubricating oil supply device for a cycle outboard motor, an oil pan is provided below the engine, and a lower end of the crankshaft is provided.
With a flywheel and coaxial drive shaft
When connected, the drive shaft and the crankshaft have the same linear output.
A shaft, and the flywheel and the
Oil pump for pumping lubricating oil to the area between the oil pan
And a wheel room to accommodate the flywheel.
Outside the flywheel of the exhaust guide to be configured
The part has a lubricating oil return passage from the lubricated part to the oil pan.
Lubricating oil supply device of four-stroke outboard motor, characterized by being made. 2. The vehicle according to claim 1, wherein a mount member for attaching the outboard motor to a hull is fixed near the oil pan, and the oil pump is provided between the mount member and the flywheel. A lubricating oil supply device for a four-cycle outboard motor, wherein the lubricating oil supply device is provided. 3. The oil pump according to claim 1, wherein the drive shaft is vertically divided in the vicinity of the flywheel, and a connecting body of the divided body constitutes a rotating body of the oil pump. A lubricating oil supply device for a 4-cycle outboard motor. 4. An exhaust guide for guiding exhaust gas downward between a cylinder block and a crankcase and an oil pan according to any one of claims 2 and 3, wherein the exhaust guide and the cylinder block are provided. A lubricating oil supply device for a four-stroke outboard motor, wherein a wheel chamber for accommodating the flywheel is formed between the lower end of the crankcase and the oil pump. . 5. The lubricating oil for a four-stroke outboard motor according to claim 4, wherein said exhaust guide is divided into upper and lower parts, and a part of an oil passage is formed between said divided surfaces. Feeding device.