JP3506244B2 - 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 an outboard motor equipped with an engine having a crankshaft oriented vertically.

[0002]

2. Description of the Related Art In a conventional outboard motor, an engine (vertical engine) having a flywheel provided at an upper end portion protruding from an engine block of a vertically oriented crankshaft is mounted in a body case of the outboard motor. A case in which a case is attached to a hull via a vibration-proof mount is generally used. For example, JP-A-63-192917 or JP-A-63-
No. 192918 discloses such an outboard motor.

In these outboard motors, a ring gear is provided on the outer periphery of the flywheel, and a starter motor for starting that meshes with the ring gear is provided above the side of the engine. A drive pulley of the valve drive winding transmission is provided below the flywheel at the crankshaft end on the flywheel side.

Usually, the flywheel has a downward bowl shape because the generator is constructed by accommodating the ignition power coil and the charging power coil in the flywheel.

[0005]

In such a conventional outboard motor, a flywheel, which is heavy and has a large moment of inertia, which greatly influences the determination of the center of gravity of the engine, is separated from the antivibration mount to a far upper position, and Since the crankshaft end on the side opposite to is connected to the drive shaft that transmits the driving force to the propeller, the factor of torsional vibration increases and has a considerable influence on the determination of the antivibration mount. Had to give special consideration to the selection of.

In addition, the starter must be provided above the engine, which, together with the above-mentioned arrangement of the flywheel, raises the center of gravity of the engine and increases the required moment when the outboard motor is tilted up. Along with
In the arrangement of other auxiliaries, especially in a multi-cylinder engine with three or more cylinders, electrical components and other auxiliaries such as CDI
There was a restriction on the degree of freedom in arranging the electrical equipment box that houses the unit and multiple coils and the intake system auxiliary equipment.

Further, in the four-cycle engine of the outboard motor, a drive pulley of a winding transmission device is provided at the crankshaft end on the flywheel side as a valve drive device for the valve drive device. A large shaft diameter is required to mount the flywheel, and therefore the diameter of the vibration pulley must be increased.As a result, the driven pulley on the camshaft side also becomes larger, occupying the vicinity of the upper part of the cylinder head. The size of the upper part of the rear end of the engine cover, which is away from the vehicle, is increased. However, since this portion of the engine cover is a portion that easily interferes with the hull structure when the outboard motor is rotated upward about the tilt axis, it is not desirable that the portion be unnecessarily enlarged. It is also disadvantageous in terms of the moment required to rotate the outboard motor.

Incidentally, as an engine alone, the actual engine is 3-
No. 21509 and Japanese Utility Model Laid-Open No. 3-23609 propose an engine in which the crankshaft is oriented vertically, and a flywheel is provided at the lower end portion protruding from the engine block of the crankshaft. Is a system in which a transmission device is connected to the lower end side of a crankshaft provided with a flywheel, and is not applicable as an engine for an outboard motor as it is. It does not suggest any means to solve the problem.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and in the present invention, an engine having a crankshaft oriented vertically is mounted on the upper portion of a main body case. In an outboard motor in which the body case is attached to a hull so as to be tiltable via a vibration-proof mount, an exhaust passage extending in a vertical direction is provided on one side of the engine body, and the engine body of the crankshaft is provided. A flywheel is provided on the lower end protruding from the engine, a ring gear is provided on the outer periphery of the flywheel, and a starter device that engages with the ring gear is provided downward on one side of the engine body on the side of the exhaust passage, An intake device is provided on the other side of the main body.

According to the present invention, the flywheel is provided on the lower end portion of the crankshaft, that is, on the drive shaft side which is connected to the crankshaft and transmits the driving force to the propeller. The center of gravity of the vehicle becomes lower and the required moment when the outboard motor tilts up becomes smaller.

[0011]

Furthermore, since the intake device is provided on the other side of the engine body, the entire outboard motor can be made compact.

[0013]

1 is an overall side view of an outboard motor 1 to which the present invention is applied. Reference numeral 1a denotes an outboard motor main body case including an extension case 2, a gear case 3, and the like. The engine 4 is mounted on an upper portion of the outboard motor main body case, and an engine cover 5 covers the upper portion thereof.

The outboard motor 1 is mounted on the stern 7 via a mounting device 6. The mounting device 6 includes a bracket 8 fixed to the stern 7 via bolts, and a swivel case 10 pivotally attached to the bracket 8 via a tilt shaft 9 horizontally mounted on the front end thereof so as to be vertically swingable. A swivel shaft 11 is pivotally supported in a swivel case 10 so as to be vertically oriented. The outboard motor 1 connects the swivel shaft 11 with upper and lower connecting members.
They are connected via 12, 12a. Therefore, the outboard motor 1 can swing up and down around the tilt shaft 9 and can swing left and right around the axis of the swivel shaft 11.

The crankshaft 13 of the engine 4 is oriented vertically, and the drive shaft 14 connected to the crankshaft 13 extends downward in the extension case 2 and reaches the gear case 3. The lower end of the drive shaft 14 is connected to the propeller shaft 16 in the gear case 3 via the forward / reverse switching device 15, and the propeller 17 is transmitted via the crankshaft 13, the drive shaft 14, the forward / backward switching device 15 and the propeller shaft 16. It is driven to rotate by engine power. Reference numeral 18 denotes an operation shaft for switching between forward and backward movement, which rotatably penetrates through the swivel shaft 11 and extends upward.

FIG. 2 is a vertical side view of the engine 4. As described above, the crankshaft 13 is oriented vertically. As shown in FIG. 1, the engine 4 is mounted with the crankshaft 13 positioned near the front (outboard side) of the outboard motor 1. That is, in FIG. 2, the right side corresponds to the front side of the outboard motor 1.

The main body of the engine 4 is composed of a main block 19, a cylinder head 20 and a cylinder head cover 21. The main block 19 is a cylinder block integrally provided with a skirt portion that forms a half part of the crankcase.
19a and the remaining crankcase portion 19b with bolts 22
a (FIGS. 4 and 5) are integrally connected. In this main block 19, four cylinders 23 are vertically arranged in a line. That is, the engine 4 is an in-line four-cylinder four-cycle engine, and each piston 24 is connected via a connecting rod 25 to one crankshaft 13 oriented vertically. Crankshaft 13 is cylinder block 19a
Side and the crankcase portion 19b side are provided with bolts 22b
Are fastened to each other and sandwiched between bearing portions facing each other, and are pivotally supported by the main block 19.

A cam shaft 27 is vertically arranged in a valve operating chamber 26 formed in the cylinder head 20. This camshaft 27
Is the upper end 13 protruding from the main block 19 of the crankshaft 13.
a drive pulley 28 mounted on a and a driven pulley 29 mounted on the upper end of the cam shaft 27 protruding from the cylinder head 20.
And a belt 30 wound between both pulleys 28 and 29, and driven by the crankshaft 13 via a winding transmission device 31. As is well known, the cam shaft 27 engages with the intake / exhaust valves of each cylinder 23 via rocker arms, and controls the operation of these intake / exhaust valves. That is, the winding transmission device 31
Represents a part of the valve operating system of the engine 4.

The drive shaft 14 is connected to a lower end portion 13b of the crankshaft 13 projecting from the main block 19 and extends downward in the extension case 2 as described above. A disc-shaped flywheel 32 is further provided with a screw 33 at the lower end 13b.
And extends in parallel to the lower surface of the main block 19. On the other hand, on the upper end portion 13a of the crankshaft 13, a generator 34 is further mounted above the drive pulley 28 for valve operation,
The rotor 35 is fastened to the upper end portion 13a by a screw 36 so as to rotate integrally with the crankshaft 13.

In this embodiment, the flywheel 32 is formed in a relatively thin disc shape, and a low skirt portion (upper case portion) 37 opened downward is provided at the bottom of the main block 19. Formed integrally, the skirt portion
The flywheel 32 is stored in 37. A mount case (lower case portion) 38 is attached to the flat lower surface of the skirt portion 37 with bolts, and the engine 4 is mounted on the extension case 2 via the mount case 38. The skirt portion 37 is provided with a surrounding wall 37a surrounding the outer peripheral portion of the flywheel 32.

Although the flywheel 32 basically has the required inertial mass by itself, it is possible to distribute the inertial mass including the rotor 35.

Although the rotor 35 is higher in the vertical direction than the flywheel 32, its outer diameter is small and its inertial mass is much smaller than that of the flywheel 32. Therefore, the diameter of the crankshaft end 13a on the rotor 35 side is small. Can have a small diameter, and accordingly, the drive pulley 28 disposed therein can also have a small diameter. If the diameter of the driving pulley 28 is small, the diameter of the driven pulley 29 that requires twice the diameter can be correspondingly reduced, which is advantageous in making the engine compact.

The winding transmission 31 and the generator 34 are covered with a cover member 40 from above. The cover member 40 is formed such that a portion corresponding to the generator 34, that is, a portion near the front side of the engine 4 is raised and a rear side thereof is wound around the transmission 31. Although the illustrated cover member 40 is integrally formed as a whole, the cover member 40 may be formed by being divided into an upper portion and a lower portion that cover the winding transmission device 31 and the portion that covers the generator 34.
Alternatively, the winding transmission device 31 may be divided into a front part and a rear part, and a front part of the winding transmission device 31 and a part that covers the generator 34.

Below the main block 19, a portion of the skirt portion 37, which surrounds the outer periphery of the flywheel 32 by the surrounding wall 37a, projects in a circular shape toward both sides and the front side (FIGS. 4 and 5). A similar overhanging portion 38a is provided in front of the upper part of the mount case 38 so as to face this overhanging portion (FIGS. 2 and 4). It is closed from below by a part. This overhang shape is
It also leads to the result of increasing the rigidity of the surroundings.

An oil pan 57 is attached and hangs down on a flat lower surface of the mount case 38 which is formed below the projecting portion and near the rear side, and extends.
It is housed inside. The interior of the mount case 38 is partitioned by a partition wall 58, which abuts against the end surface of the surrounding wall 37a, into a portion 38b forming a storage chamber of the flywheel 32 and a portion 38c communicating with the oil pan 57.

Further, as shown in FIG. 4, the mount case 38
At its lower surface, the bolt is fastened to the upper end of the extension case 2 by a bolt 76. That is, the engine 4 is mounted on the extension case 2 via the mount case 38, and is housed in the engine room 41 whose upper part is defined by the engine cover 5. However, the lower part of the engine room 41 has a lower end periphery. It is defined by an under case 77 (FIGS. 1, 3 and 4) which is supported by the mount case 38 and surrounds the lower part of the engine and opens upward. 3 is a view of the interior of the engine room 41 seen from the side opposite to that of FIGS. 1 and 2 with the cover member covering the engine 4 cut vertically, and the lower portion of the engine 4 is shown in a sectional view similar to FIG. is there.

The engine cover 5 is detachably attached to the under case 77 so as to cover the upper opening of the under case 77 via a mating surface 78. The outer periphery of the connection portion between the mount case 38 and the extension case 2 is covered with an under cover 80 fastened to the under case 77 with screws 79 (FIG. 3), and the under case 77, the under cover 80, and the extension case 2 are connected. Outboard motor body 1
A smooth contour shape is given to a.

The upper surface of the engine cover 5 is the cover member.
It is shaped like 40 (Figs. 3, 6, 7).
That is, the portion 5a corresponding to the front generator 34 is raised,
The rear portion 5b is formed low. An air intake device 42 having a pair of left and right passage members 43 is arranged on the rear portion 5b formed to be low. Each passage member
As shown in FIG. 7, 43 is connected to the peripheral portion of the opening 5c provided in the engine cover portion 5b and extends upward, and a notch-shaped air introduction portion 43a is provided at the upper opening edge portion. There is.

The passage member 43 is covered with a covering member 45 above the passage member 43. The cover member 45 is fixed to the engine cover 5 with a bolt 44 at a front position intermediate between the left and right passage members 43. The cover member 45 includes an upper plate portion 45a that covers the upper side of the passage member 43 and side plate portions that hang down along the left and right edges thereof.
It consists of 45b. Since the passage member 43 erected on the lower engine cover portion 5b extends to the substantially same height position behind the generator 34 so as to overlap with the rear portion of the generator 34, the upper surface of the cover member 45 has the upper surface of the front engine cover portion 5a. Does not project from the upper surface of the and extends rearward flush with the upper surface.

Outside air freely flows into the void formed on the engine cover portion 5b by being covered by the covering member 45 on the upper and both sides, and the passage is opened as shown by an arrow a in FIG. It is introduced into the engine room 41 through the member 43 and is used as intake air for the engine 4.
Cool around.

FIG. 5 is a schematic plan view showing the arrangement of the engine 4 and accessories in the engine room 41. 46
Is an intake valve, 47 is an exhaust valve, 48 and 48 are rocker arms, and such a valve mechanism whose opening and closing is controlled by the cam shaft 27 is provided for each cylinder 23. 49 is the cylinder head
In the intake port provided in 20, the intake pipe 50 connected to the intake port 49 extends forward along the side surface of the engine 4,
A part of the air introduced into the engine room 41 through the passage member 43 is sucked into the intake pipe 50 from the front end of the intake pipe 50, and is sucked into the cylinder 23 through the intake port 49. 51
Is a vaporizer and 51a is an intake silencer box. Such an intake pipe
50 is provided for each cylinder 23 and is arranged in parallel in the vertical direction along the side surface of the engine 4.

An exhaust passage 52 extends vertically in the other side portion of the engine 4, and each cylinder 23 is inserted into the exhaust passage 52.
The exhaust port 53 corresponding to is communicating. The exhaust passage 52 is connected to the upper end of an exhaust pipe (not shown) extending in the extension case 2 in the vertical direction, and the exhaust gas is discharged into the water from the lower end through the exhaust pipe.

On the same side as the exhaust passage 52 of the engine 4, an electric equipment box 54 containing electric equipment is arranged in the front, and a starter motor 55 is arranged below it (see FIGS. 3 and 4). 54a is a spark plug cord, which is a cylinder head
Connected to 20 side spark plugs. Electrical box
An ignition coil 54b, a CDI unit 54c, and the like are housed in the 54, but since the engine of this embodiment is a 4-cycle 4-cylinder engine, one coil for each two cylinders, a total of two coils 54b, is used for ignition. These coils are rationally arranged in the space above the starter motor 55, and the CDI unit 54c is arranged on the front side so as not to interfere with the starter motor 55. Output shaft of starter motor 55
55a is gear-engaged with a ring gear 56 (FIGS. 2 and 4) provided on the outer periphery of the flywheel 32.

As shown in FIG. 2, an oil suction pipe 60 having a strainer 59 at the lower end extends upward from the bottom of the oil pan 57 through the oil pan communicating portion 38c of the mount case 38, and at the bottom of the main block 19. It is connected to the formed oil suction passage 61. The oil intake passage 61 is provided at the lower end of the cam shaft 27 and communicates with an intake port 63 of an oil pump 62 driven by the cam shaft 27.

The oil pressurized by the oil pump 62 is sent to the bearings around the cam shaft 27, and the cylinder head 20, the cylinder block 19a, and the crankcase 19 are also included.
The oil is sent to an oil filter 68 attached to the front surface of the crankcase 19b through an oil passage (not shown) penetrating through b. The oil discharged from the oil filter 68 flows into an oil passage 69 (see FIG. 5) vertically arranged at the center of the crankcase 19b in the left-right direction of the front surface, and further passes through an oil passage 70 to pass through the oil passage 70. Reach each main bearing 39 and lubricate these bearings.

This oil further reaches the inside of the crank pin bearing 71 and the cylinder 23 through the oil passage 72 formed in the crank shaft 13, and lubricates the crank pin bearing 71 and the inner surface of the cylinder. Since the cylinders 23 arranged in a row in the vertical direction communicate with each other through the oil ports 73 at positions close to the crank chambers, the oil in the cylinders 23 sequentially flows downward through these oil ports 73, The oil is discharged from the lowermost oil port 73a to the vicinity of the lower end of the crankshaft 13. However, this oil does not flow into the chamber accommodating the flywheel 32, but the return oil passage 82 (FIG. 4) for returning the oil between the main bearing 39b at the lower end and the crankshaft oil seal 81, and the flywheel accommodating Return oil passage 83 that bypasses the outside of the room and returns the oil
After going through (FIG. 4), it reaches the oil pan communicating portion 38c of the mount case 38, and then is returned into the oil pan 57.

The oil lubricated around the cam shaft 27 reaches the oil return port 65 through the oil passage 74, and the oil return passage
64, and returned to the oil pan 57 via the oil return pipe 66. Since the oil pan 57 hangs from the mount case 38 into the extension case 2, this does not increase the mounting height of the engine. The drain plug 84 provided at the bottom front end of the oil pan 57, as shown in FIG.
It faces the recess 85 formed in the extension case 2. The recess 85 may be provided on the side portion of the extension case 2, and the drain plaque 84 may be faced to this.

The mount case 38 is connected to the pair of left and right connecting members 12 (FIG. 1) via a mount rubber 75 extending in the left-right direction. Mount rubber 75 is core material 75a
And a rubber 75b surrounding the connecting member 12
Are bolted to the core material 75a.

[Brief description of drawings]

FIG. 1 is an overall side view of an outboard motor to which the present invention has been applied.

FIG. 2 is a vertical sectional side view of an engine.

FIG. 3 is a side view showing an inside of an engine room with a cover member covering the engine cut vertically.

FIG. 4 is a cross-sectional view substantially along the line IV-IV in FIG.

FIG. 5 is a schematic plan view showing an arrangement of an engine and accessories in the engine room.

FIG. 6 is a central longitudinal sectional view of an upper portion of an engine cover.

FIG. 7 is a lateral vertical sectional view of an upper portion of an engine cover.

[Explanation of symbols]

1 ... Outboard motor, 1a ... Outboard motor main body case, 2 ... Extension case, 3 ... Gear case, 4 ... Engine, 5 ... Engine cover, 6 ... Mounting device, 7 ... Stern, 8 ... Bracket, 9 ... Tilt shaft, 10 ... Swivel case, 11 ... Swivel shaft, 12 ... Coupling member, 13 ... Crank shaft, 14 ... Drive shaft, 15 ...
Forward / reverse switching device, 16 ... Propeller shaft, 17 ... Propeller, 18 ...
Operating axis, 19 ... Main block, 20 ... Cylinder head, 21 ... Cylinder head cover, 22 ... Bolt, 23 ... Cylinder, 24 ...
Piston, 25 ... Connecting rod, 26 ... Valve chamber, 27 ... Cam shaft, 28 ...
Drive pulley, 29 ... Driven pulley, 30 ... Belt, 31 ... Winding transmission device, 32 ... Flywheel, 33 ... Screw, 34 ... Generator, 35 ... Rotor, 36 ... Screw, 37 ... Skirt part, 38 ... Mount Case, 39 ... Main bearing, 40 ... Cover member, 41 ... Engine room, 42 ... Air intake device, 43 ... Passage member, 44 ...
Bolt, 45 ... Cover member, 46 ... Intake valve, 47 ... Exhaust valve, 48 ...
Rocker arm, 49 ... Intake port, 50 ... Intake pipe, 51 ... Vaporizer, 52 ... Exhaust passage, 53 ... Exhaust port, 54 ... Electrical box, 55 ... Starter motor, 56 ... Ring gear, 57 ... Oil pan, 58 ... Bulkhead, 59 ... strainer, 60 ... oil suction pipe,
61 ... Oil suction passage, 62 ... Oil pump, 63 ... Suction port,
64 ... Oil return passage, 65 ... Oil return port, 66 ... Oil return pipe, 67 ... Discharge port, 68 ... Oil filter, 69 ... Oil passage, 70 ... Oil passage, 71 ... Crankpin bearing, 72 ... Oil passage, 73 …
Oil port, 74 ... Oil passage, 75 ... Mount rubber, 76 ... Bolt, 77 ... Under case, 78 ... Mating surface, 79 ... Screw, 80 ... Under cover, 81 ... Oil seal, 82, 83 ... Return oil passage, 84
… Drain plug, 85… Recess.

Continuation of the front page (56) References JP-A-8-68335 (JP, A) JP-A-63-192917 (JP, A) JP-A-6-129257 (JP, A) Actual Kaihei 3-21509 (JP , U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02B 67/00 F02B 77/00 F02B 61/04 F02B 61/06 B63H 20/00 F01M 11/03 F02F 7/00

Claims (9)

(57) [Claims] 1. An outboard motor in which an engine having a crankshaft oriented vertically is mounted on an upper part of a main body case, and the main body case is attached to a hull via a vibration-proof mount so as to be tiltable . A vertical extension on one side
An air passage is provided, a flywheel is provided at a lower end portion of the crankshaft projecting from the engine main body portion, a ring gear is provided on an outer circumference of the flywheel, and the one side of the engine main body portion is below the side portion on the exhaust passage side. A ship in which a starting device that meshes with a ring gear is provided downward, and an intake device is provided on the other side of the engine body.
Outside machine . 2. The outboard motor according to claim 1, further comprising an oil filter provided on a crankcase side of the engine body. 3. The outboard motor according to claim 1, further comprising a valve drive device provided below the upper end of the crankshaft. 4. The outboard motor according to claim 3, wherein the valve drive device is a winding transmission device. 5. The outboard motor according to claim 4, wherein the engine is provided with a cover device that covers the winding transmission device from above. 6. The outboard motor according to claim 1, further comprising an oil pan provided below the engine body. 7. A case portion that covers the flywheel from above and a case portion that covers the flywheel from below are provided on the lower side of the engine body, and an oil pan is provided on the lower surface of the case portion that covers from below. The outboard motor according to claim 1, wherein the oil pan and the engine body are communicated with each other through an oil passage. 8. The engine is mounted with the crankshaft positioned near the front of the outboard motor, and the engine cover defining at least a part of an engine room accommodating the engine is mounted on an upper surface of the crankshaft from an upper end thereof. The outboard motor according to claim 1, wherein an outside air intake device is provided at a position closer to the rear. 9. The outboard outboard vehicle according to claim 8, wherein the outside air intake device includes a passage member that communicates with the inside of the engine cover and extends upward from the cover to a position substantially at the same height as the upper surface of the generator. Machine.