JPH11141323A - Engine unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve freedom of design of an engine unit in producing a plurality of kinds of engines having different inclination of cylinder axes. SOLUTION: In an engine unit 3, connection surfaces 22, 59 are formed on a side portion of an assembly C composed of a cylinder block 12 and a crank case 11, on its surface perpendicular to a horizontally extending crank shaft 15. Auxiliary members 52, 61 are attached to the connection surfaces. A mount or an engine hanger 58 are arranged on the auxiliary members for supporting the assembly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improvement in an engine unit.

[0002]

2. Description of the Related Art Generally, an engine unit is mounted at a predetermined position by a mount. As such an engine unit, there is, for example, Japanese Unexamined Patent Publication No. 3-262792 "Small boat". The above-mentioned small boat is the first
According to FIG. 2, FIG. 2 and FIG. 3 (a), the engine is mounted on the bottom 1a of the hull 1 (the numbers are cited in the gazette; the same applies hereinafter) via four mounts 2h. 2 is installed. The engine 2 is a four-cycle engine in which the cylinder shaft 2e is inclined. The four-cycle engine has four mounts 2h provided on a cylinder head 2c and a cylinder block 2d.

[0003]

The engine 2
In some cases, even if engines having the same performance are produced, a plurality of types may be produced by simply changing the inclination of the cylinder shaft 2e or changing the support mode and the support position of the mounts 2h. However, since the mounts 2h are provided on the cylinder head 2c and the cylinder block 2d, it is necessary to change the cylinder head 2c and the cylinder block 2d for each type of the engine 2, and the degree of freedom in design is small.

It is an object of the present invention to increase the degree of freedom in designing engine units when producing a plurality of types of engine units having different cylinder axis inclinations.

[0005]

According to a first aspect of the present invention, there is provided an apparatus comprising a cylinder block and a crankcase, which is orthogonal to a horizontally extending crankshaft. Forming a bonding surface on the surface,
An auxiliary member is attached to the coupling surface, and a mount for supporting the assembly is provided on the auxiliary member. (1) When producing a plurality of types of engine units having different inclinations of the cylinder axis, it is only necessary to change the auxiliary member and not to change the assembly, or to change the coupling surface only with a minimum change. In addition, many types of engine units have many common parts. (2) The support form and support position of the mount can be variously changed only by replacing the auxiliary member.

According to a second aspect of the present invention, a connecting surface is formed on a side portion of an assembly including a cylinder block and a crankcase, and on a surface orthogonal to a horizontally extending crankshaft, and an auxiliary surface is formed on the connecting surface. A member is attached, and an engine hanger for suspending the assembly is provided in the upper half of the auxiliary member. (1) When producing a plurality of types of engine units having different inclinations of the cylinder axis, it is only necessary to change the auxiliary member and not to change the assembly, or to change the coupling surface only with a minimum change. In addition, many types of engine units have many common parts. (2) The hanging mode and the hanging position of the engine hanger can be variously changed only by replacing the auxiliary member.

The invention according to claim 3 is characterized in that the connecting surfaces are on both sides of the assembly, and an auxiliary member is attached to each of the connecting surfaces. Since auxiliary members are mounted on both sides of the assembly, various auxiliary members such as an oil tank can be dispersed and mounted on the assembly.

The invention according to claim 4 is characterized in that the auxiliary member is a wheel case that covers at least a part of the flywheel. The wheel case can be easily attached to the assembly.

According to a fifth aspect of the present invention, the engine unit is a four-stroke engine, and the auxiliary member is a member forming a part of an oil passage to an oil pump. The structure of the oil pipe to the four-stroke engine oil pump is simple.

According to a sixth aspect of the present invention, the engine unit is a dry sump type four-cycle engine, and the auxiliary member is a member forming a part of an oil tank. The dry sump type four-stroke engine does not require a separate oil tank.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is a side view of a small boat equipped with a dry sump lubricated four-stroke engine unit according to the present invention. The small boat 1 indicated by imaginary lines is used for leisure or the like, and has an engine compartment of a hull 2. A dry-sump lubricated four-cycle engine unit 3 is mounted on 2a, and a jet pump 4 is driven by the engine unit 3. The jet pump 4 pressurizes water sucked from the bottom of the hull 2 and discharges the water backward as a jet stream. That will move you forward.

In the dry sump lubrication system, lubricating oil is supplied to each lubricating portion of the engine unit 3 from a lubricating oil tank provided outside the half crankcase, and excess lubricating oil is temporarily supplied to the bottom of the half crankcase. The lubrication system collects the lubricating oil and pumps it to a lubricating oil tank with a lubricating oil pump. 2d is a bulkhead, 2e is a sheet,
2f is a deck, 2g is a steering bar, 5 is a water inlet,
6 is a discharge nozzle and 7 is a fuel tank.

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and shows an engine room 2a (formed by a lower hull 2b and an upper hull 2c).
Fig. 1 shows a state in which a dry sump lubricated four-cycle engine unit 3 is mounted. The engine unit 3 is a horizontal engine unit in which the crankshaft 15 extends in the front-rear direction of the small boat 1 (front and rear directions in the figure), and the cylinder axis L is inclined in the upper left direction in the figure.

FIG. 3 is a sectional view taken along the line 3-3 in FIG. 2, and shows a sectional structure of the engine unit 3 for taking out engine power toward the rear (left side in the figure) of the small boat 1. In this figure, the area around the suction pipe 72 and the suction oil passage 24a (the range indicated by reference numeral AA) is shifted from the line 3-3 in FIG. 2, but is the same cross section as other parts for convenience of explanation. Indicated by The engine unit 3 includes an engine body 10 and
Valve drive mechanism 4 attached to the front of engine body 10
0 and flywheel unit 50 and engine body 1
0 is a horizontal three-cylinder engine comprising a lubrication unit 60 attached to the rear of the engine.

The engine body 10 includes a half crankcase (crankcase) 11, a cylinder block 12 having three cylinders 12a in the front-rear direction (... indicates a plurality, the same applies hereinafter), and a cylinder head 13. , A head cover 14, a laterally extending (horizontally extending) crankshaft 15, a piston 16 connected to the crankshaft 15 and inserted into each cylinder 12a, and a PTO shaft (connected to a rear end of the crankshaft 15). The main components are a power take-out shaft 17, a valve train 18 formed by the cylinder head 13 and the head cover 14, and a valve train 30 housed in the valve train 18. The PTO shaft 17
Extends rearward from the lubrication unit 60 (opposite the engine) and is connected to the drive shaft 4a of the jet pump 4 shown in FIG. A connecting portion 17a is connected to the crankshaft 15, and a connecting portion 17b is a power take-out connecting portion. These connecting portions 17a and 17b are made of a female screw or a female spline.

At the bottom of the half crankcase 11, three collecting portions 11a for collecting the lubricating oil remaining after lubricating the respective sliding portions are collected by these collecting portions 11a. A guide path 11b for guiding lubricating oil, and a guide path 11b
Oil passage 1 for returning lubricating oil from lubrication unit 60 to lubrication unit 60
1c. The collecting parts 11a approach the crankshaft 15 to such an extent that the accumulated lubricating oil does not contact the counterweight (web) of the crankshaft 15, and the baffle plates 21 between the crankshaft 15 and the lower oil surface. A partitioned, small-capacity oil sump. For this reason, the half crankcase 11 can be reduced in size because the bottom can be close to the crankshaft 15. As a result, when setting the mounting position of the engine unit 2 on the small boat 1 (see FIG. 2), the influence of interference between the bottom of the engine unit 2 and the boat bottom can be reduced. And, despite the small size of the half crankcase 11, the crankshaft 15 hardly comes into contact with the lubricating oil, the friction loss at the time of rotation is suppressed, and aeration (splashing of oil) occurs.
Is also prevented.

The valve drive mechanism 40 includes a crankshaft 1
5, a belt driving mechanism for driving the camshaft 31 of the valve mechanism 30. The driving pulley 41 is fixed to the crankshaft 15 projecting from the front side of the half crankcase 11.
A driven pulley 42 fixed to the camshaft 31 protruding from the front side of the cylinder head 13, and a timing belt 43 hung between the driving and driven pulleys 41, 42.
And a belt tensioner 44 for adjusting the tension of the timing belt 43. 45 is a belt cover.

The flywheel unit 50 includes a flywheel 51 bolted to the front end of the crankshaft 15, a wheel case 52 covering at least a part of the flywheel 51, and an open end ( (A front end portion). That is, an assembly C composed of the cylinder block 12 and the half crankcase 11 (hereinafter referred to as “assembly C”)
Say ) Is a configuration in which a coupling surface 59 is formed on a side portion and a surface orthogonal to the crankshaft 15, and a wheel case 52 as an auxiliary member is attached to the coupling surface 59 with a bolt 101. Therefore, the wheel case 52 can be easily attached to the assembly. The flywheel unit 50 is located ahead of the drive pulley 41 (on the side opposite to the cylinder block 12). 102 is a lid 53
It is a bolt to attach.

Reference numeral 54 denotes a generator, which comprises a rotor 54a attached to the inner peripheral surface of the flywheel 51 and a coil 54b attached to the wheel case 52. 55 is a ring gear attached to the outer peripheral surface of the flywheel 51,
It is connected to a starter motor described later. 57 is an inspection cap for closing a hole for checking the crank angle.

The lubrication unit 60 includes the cylinder block 1
A lubricating oil tank 61 bolted to the rear side of an assembly including the crankcase 2 and the half crankcase 11; a lid 63 closing an open end (rear end) of the lubricating oil tank 61; 11 to the lubricating oil tank 61
A return pump 64 for returning the lubricating oil to the engine, a supply pump 65 for supplying the lubricating oil from the lubricating oil tank 61 to each sliding portion of the engine body 10, and a pipeline. The return pump 64 is a pump built in the lubricating oil tank 61 and a supply pump 65
Is a pump independent of the lubricating oil tank 61.

More specifically, a tank mounting packing surface (flange) 22 as a coupling surface is formed on the side of the assembly C and on a surface orthogonal to the crankshaft 15. On the other hand, a first packing surface (flange) 61 a and a second packing surface (flange) 6
1b was formed. The second packing surface 61b is located behind the first packing surface 61a (from the cylinder block 12 to the PTO shaft 1).
7). Then, the first packing surface 61a is aligned with the tank mounting packing surface 22 via the packing 23, and is bolted.
A lubricating oil tank 61 as an auxiliary member is attached to
A lid 63 is provided on the second packing surface 61 b via a packing 62.
And bolted together. Such a lubricating oil tank 61 is sealed by the side wall of the assembly and the lid 63,
It is a closed tank for storing lubricating oil, that is, a member forming a part of the oil tank. Therefore, a separate oil tank is not required, and the engine unit 3 is reduced in size.

As is clear from the above description, the engine unit 3 is provided with the connecting surfaces 22, 59 on both sides of the assembly C, and the auxiliary members (the wheel case 52 and the lubricating oil tank 61) are provided on these connecting surfaces 22, 59. ) Is attached.
Therefore, various auxiliary members such as the lubricating oil tank 61 can be dispersed and attached to the assembly, and the engine unit 3 is reduced in size.

The return pump 64 includes a case portion 61c formed integrally with the lubricating oil tank 61, an inner cover 64a closing the case portion 61c, an inner rotor 64b and an outer rotor 64c housed in the case portion 61c, and A shaft 64f connected to the crankshaft 15 via a drive mechanism (comprising a drive gear 64d and a driven gear 64e) to drive the outer rotors 64b, 64c.
And a scavenging pump. The drive mechanism is housed in a space 66 between the lubricating oil tank 61 and the assembly. The space 66 also serves as a part of a breather passage for communicating the valve chamber 18 with the crank chamber 19. 67 is a bolt for attaching the inner cover 64a to the case 61c.

The supply pump 65 includes a case body 65a bolted to the side of an assembly including the cylinder head 13 and the head cover 14, a cover 65b closing the case body 65a, and an inner rotor 65c housed in the case body 65a. And a shaft 65e that is directly connected to the camshaft 31 of the valve mechanism 30 to drive the inner and outer rotors 65c and 65d. The shaft of the return pump 64 and the shafts 64f and 65e of the supply pump 65 are connected to the crankshaft 15
And extends parallel to the camshaft 31. An assembly composed of the cylinder block 12 and the cylinder head 13 includes a suction oil passage 24a and a discharge oil passage 24b for the supply pump 65.
(See FIG. 7).

FIG. 4 is a sectional view of the engine body according to the present invention, showing the engine body 10 in which the cylinder axis L is inclined in the upper left direction in the figure. The valve operating mechanism 30 includes a camshaft 31
And rocker shafts 32, 32 and rocker arms 33, 33
And an intake valve 34 and an exhaust valve 35. The cylinder head 13 includes an intake passage 13a and an exhaust passage 13b, and a floatless diaphragm carburetor 82 communicates with the intake passage 13a via an intake pipe 81.
An exhaust passage 12b of the cylinder block 12 communicates with 3b. The head cover 14 has a first breather chamber 18a for recirculating blow-by gas above the valve operating chamber 18.

Each of the baffle plates 21 is fixed to the half crankcase 11 and partitions a range corresponding to the downstream side (left side in the drawing) in the rotation direction of the crankshaft 15. One portion is locked to the bottom of the crankcase 11 with a positioning locking protrusion 11d, and the other portion is fixed by bolting. Note that the entire necessary range may be partitioned by one baffle plate. 26 is a supply oil passage, and the discharge oil passage 24
b (see FIG. 7) and the supply pump 6 via the filter 25
5 (see FIG. 7), which is an oil passage for supplying lubricating oil to each sliding portion of the engine body 10. 27 is an oil return tube for returning lubricating oil from the valve operating chamber 18 to the crank chamber 19;
In the present embodiment, the nozzle 13c of the cylinder head 13
And the nozzle 11 in the lower half of the half crankcase 11
e, the collection unit 11a and the guiding unit 11
b. Reference numeral 28 denotes a communication passage that communicates the valve chamber 18 with the crank chamber 19. Reference numeral 11f denotes a drain hole for extracting drain from the collection unit 11a, and 12c... Denote cooling water passages.

FIG. 5 is an exploded plan view of the lubricating oil tank and the lid according to the present invention, and shows the direction of the axis S of the crankshaft 15 (the crankshaft 15) along the assembly including the cylinder block 12 and the half crankcase 11. This indicates that the lubricating oil tank 61 swells in the direction in which the lubricating oil extends, and that the lubricating oil is also stored in the bulging portion 61d. In the lubricating oil tank 61, since the lubricating oil can be stored also in the bulging portion 61d along the assembly, the lubricating oil tank 61 having the same capacity can be stored.
Even in this case, the front-rear dimension and the vertical dimension can be reduced, so that the engine unit 3 can be reduced in size. In the figure, 61
r is a lubricating oil supply port cap, 68 is a bolt for attaching the lubricating oil tank 61 to the half crankcase 11 and the cylinder block 12, and 69 is a bolt for attaching the lid 63 to the lubricating oil tank 61.

FIG. 6 shows a dry sump lubrication type 4 according to the present invention.
FIG. 3 is a rear view of the cycle engine unit with a lubricating oil tank removed, and shows a tank mounting packing surface 22 of an assembly including a cylinder block 12 and a half crankcase 11.
Indicates that it is open. .., 29A, 29B,... Are breather passages through a space surrounded by the tank mounting packing surface 22 (corresponding to the space 66 shown in FIG. 3).
The valve chamber 18 communicates with the crank chamber 19.
That is, the breather passage 29A and the breather passage 29B ...
Is in communication with Reference numeral 56 denotes a starter motor.
The engine unit 3 is started by rotating the flywheel 51 via a ring gear 55 shown in FIG. By connecting the intake muffler box 83 to the carburetor 82, the intake pipe 81, the carburetor 82 and the intake muffler box 83 form an intake line of the engine body 10. 83a is an intake port, and 84 is a bolt for attaching the intake muffler box 83 to the mount 8.

FIG. 7 shows a dry sump lubrication type 4 according to the present invention.
FIG. 5 is a rear view of the cycle engine unit with a lid for a lubricating oil tank removed, showing a second packing surface 61 of the lubricating oil tank 61;
b indicates that it is open. Lubricating oil tank 61
Is a suction oil passage 61e and a discharge oil passage 61f for the return pump 64, an oil reservoir 61g connected to the bulging portion 61d (see FIG. 5) for storing lubricating oil, and a second oil reservoir 61g higher than the oil reservoir 61g. The breather chamber 61h and the engine exhaust port 61i are integrally formed. As described above, the lubricating oil tank 61 is a member that forms part of the suction oil passage 61e and the discharge oil passage 61f (oil passage) to the return pump 64 (oil pump). For this reason, the structure of the oil pipe is simplified, and the number of piping steps is reduced. The suction oil passage 61e and the oil reservoir 61g are located at left and right positions so as to straddle the PTO shaft 17, and the return pump 64 and the supply pump 65 are located at a position passing through the cylinder axis L. 17
There is a return pump 64 at a higher level, and this return pump 64
There is a supply pump 65 at a higher level. Engine exhaust port 61
i is an exhaust port that connects the exhaust passage 12b shown in FIG. 6 with an external exhaust pipe.

A suction pipe 72 with a strainer 71 for the supply pump 65 is housed in the oil reservoir 61g, and the upper end of the suction pipe 72 communicates with the suction oil passage 24a for the supply pump 65 (see FIG. 3). In the figure, 61m... Are oil baffle preventing baffle walls 61 provided vertically in three stages in an oil sump 61g.
n is a cooling water port communicating with the cooling water passage 12c and the external cooling pipe shown in FIG. Reference numeral 75 denotes a third breather tube, which connects the lubricating oil tank 61 to the valve operating chamber 1 through a gas port 61q.
8 (see FIG. 3).

FIG. 8 is a cross-sectional view of the lubricating oil tank according to the present invention. The bulging portion 61d of the lubricating oil tank 61 bulges along the assembly composed of the cylinder block 12 and the half crankcase 11. Show the shape. The bulging portion 61d is disposed above the position of the suction port of the strainer 71, so that even when the engine unit 3 is tilted due to the movement of the hull 2 (see FIG. 2), the suction port remains in the oil. It is considered as it is. The second breather chamber 61h has a labyrinth structure, and details thereof will be described with reference to FIG. In the figure, 12d is the wall of the cylinder block 12, 61
s is the wall of the lubricating oil tank 61, 61t is the inclined bottom of the bulging portion 61d, 71a is the support stay of the strainer 71, 73
Is a first breather tube. Reference numeral 76 denotes an oil return tube which plays a role of returning lubricating oil from the second breather chamber 61h to the crank chamber 19 via the wall 61s.

FIG. 9 is a perspective sectional view of a second breather chamber according to the present invention, showing three partition walls 61 of a lubricating oil tank 61.
o ... and the three partition walls 63a ... of the lid 63
The breather room 61h is divided into three rooms, and each of the partition walls 61 is further divided.
small notches 61p, 63b ... alternately in o ..., 63a ...
Indicates that the second breather chamber 61h has a labyrinth structure. The second breather chamber 61h includes a gas inlet 61j and a gas outlet 61k. Gas inlet 61j
Communicates with the first breather chamber 18a (see FIG. 4) via the first breather tube 73. Gas outlet 6
1k communicates with the upstream of the carburetor 82 (the communication pipe between the intake muffler 83 and the carburetor 82) via the second breather tube 74.

Next, the operation of the dry sump lubricated four-cycle engine unit 3 having the above structure will be described with reference to FIGS.
It will be described based on. The return pump 64 of FIG.
The lubricating oil collected in 1a...
1c → the suction oil passage 61e → the return pump 64 → the discharge oil passage 61f shown in FIG. 7 supplies the lubricating oil accumulated in the oil sump 61g to the strainer 71 → the suction pipe 72 → the suction oil passage 24.
a → supply pump 65 → discharge oil passage 24b → filter 25 in FIG. 4 → supply oil passage 26 to supply to each sliding portion of engine body 10. The lubricating oil remaining after lubricating each sliding part is
The oil returns to the crank chamber 19 through the oil return tube 27 in FIG. 4, and is collected in the lubricating oil tank 61 through the return path.

FIG. 10 is an exploded perspective view of the engine unit according to the present invention, and shows the relationship between the assembly C indicated by imaginary lines and the auxiliary members (the wheel case 52 and the lubricating oil tank 61). The wheel case 52 is provided with two left and right mounts 8 and 8 for supporting the assembly C on the side of the lower half, and an engine hanger for suspending the assembly C on the top of the upper half. 58 are provided. The same applies to the lubricating oil tank 61. 105 are engine hanger mounting bolts.

The coupling surfaces 22, 59 of the assembly C (see FIG. 3)
The auxiliary members 52 and 61 are attached to the main body. Therefore, when producing a plurality of types of engine units 3 in which the inclination of the cylinder axis L is different, only the auxiliary members 52 and 61 are changed and the assembly C is not changed. Or, only minimal changes that change the coupling surface alone are required, and the degree of freedom in design is large.
In addition, since there are many common parts in a plurality of types of engine units 3, the cost of the molding die can be reduced.

Further, the assembly C is attached to the auxiliary members 52 and 61.
Are provided, the supporting form and the supporting position of the mounts 8 can be variously changed only by replacing the auxiliary members 52, 61. Further, since the engine hangers 58, 58 for suspending the assembly C are provided on the auxiliary members 52, 61, the suspension form and the suspension position of the engine hangers 58, 58 can be achieved simply by replacing the auxiliary members 52, 61. Can be changed in various ways. Therefore, the degree of freedom in designing the engine unit 3 is increased.

FIGS. 11 (a) and 11 (b) are mounting configuration diagrams according to the present invention. FIG. 11 (a) shows a structure in which a mount 8 is mounted on a small boat 1 via a mount rubber 9.
(B) shows the plane of the mount rubber 9. The mounting structure is a mounting base 2h for the lower hull 2b in the small boat 1.
Then, a mount rubber 9 is attached with bolts 103, the mount 8 is placed on the mount rubber 9, and attached with bolts 104. According to this mount mounting structure, as shown in FIG. 2, the front, rear, left and right sides of the engine unit 3 are mounted on four mounts 8 (only two fronts are shown in this figure). It will be attached to.

The lubricating oil tank 61 shown in FIG.
Can be freely exchanged according to the installation condition of the device. For example, as shown in the following FIGS.
May be a modified example in which the direction of the cylinder axis L is changed.

FIG. 12 is a rear view of a dry sump lubricated four-stroke engine unit (modification) according to the present invention, and shows a state in which an engine body 10 having a cylinder axis L inclined in the upper right direction in FIG. . In this case,
An electronically controlled fuel injection device is installed instead of the intake system including the diaphragm type carburetor 82 and the intake muffler box 83 shown in FIG. The electronic control fuel injection device includes a throttle body 91, an acceleration pump 92, an injection valve 93, a control computer (not shown), and the like. The position of the throttle body 91 can be freely set by drawing the intake pipe 81 in accordance with the space of the narrow engine room 2a.

FIG. 13 is a rear view of the dry sump lubricated four-stroke engine unit (modification) according to the present invention with the lubricating oil tank removed, and shows a state in which the tank mounting packing surface 22 is inclined in the upper right direction in the figure. As described above, the engine unit 3 is configured such that the cylinder axis L shown in FIG. 2 is inclined in the upper left direction in the figure and the cylinder axis L shown in FIG.
Can be used in common with the case where is inclined in the upper right direction in the figure. In addition, since the cylinder axis L is inclined in the upper right direction in the figure, the communication path 28 shown in FIG. 4 is inclined obliquely downward, and serves as an oil return path for returning lubricating oil from the valve operating chamber 18 into the crank chamber 19. Fulfill. For this reason, the oil return tube 27 is unnecessary.

FIG. 14 is a rear view of the dry sump lubricated four-stroke engine unit (modified example) according to the present invention with the lubricating oil tank lid removed. This shows a state where the left and right sides are exchanged. In this case, there is no need to change the assembly C composed of the cylinder block 12 and the half crankcase 11 shown in FIG. In addition, since a relatively large mold for molding the half crankcase 11 and the cylinder block 12 can be handled by a relatively small mold such as the lubricating oil tank 61, the mold cost can be reduced.

In the above-described embodiments and modifications of the present invention, the engine unit 3 is not limited to the number of cylinders, but may be, for example, four cylinders. Lubricating oil tank 61
May be attached to at least the side of the assembly C composed of the cylinder block 12 and the half crankcase 11 and on a surface orthogonal to the crankshaft 15. For example, in the assembly C, the valve drive mechanism 40 and the flywheel unit 50 are mounted on the side where the PTO shaft 17 protrudes, and the lubrication unit 60 is mounted on the side in the opposite direction (the right side in FIG. 3). In that case, the lubricating oil tank 61 faces forward of the small boat 1.

[0043]

According to the present invention, the following effects are exhibited by the above configuration. According to the first aspect of the present invention, the coupling surface is formed on the side of the assembly and on a surface orthogonal to the horizontally extending crankshaft, and the auxiliary member is attached to the coupling surface. When a plurality of different types of engine units are produced, only the auxiliary member is changed and the assembly is not changed, or only the coupling surface is changed only with a minimum change, and the degree of freedom in design is large. Moreover,
Since there are many common parts in a plurality of types of engine units, the cost of the mold can be reduced. Further, since the mount for supporting the assembly is provided on the auxiliary member, the support form and the support position of the mount can be variously changed only by replacing the auxiliary member, thereby increasing the degree of freedom in design.

According to the second aspect of the present invention, the connecting surface is formed on the side of the assembly and on the surface orthogonal to the crankshaft extending in the horizontal direction, and the auxiliary member is attached to this connecting surface, so that the cylinder axis is extended. When producing multiple types of engine units with different inclinations, it is only necessary to change the auxiliary member and not to change the assembly, or only the minimum change to change only the coupling surface, the design flexibility is large. In addition, since there are many common parts for a plurality of types of engine units, the cost of the mold can be reduced. Furthermore, since the engine hanger for suspending the assembly is provided on the auxiliary member, it is possible to change the hanging mode and the hanging position of the engine hanger in various ways simply by replacing the auxiliary member. Grows.

According to the third aspect of the present invention, since auxiliary members are mounted on both sides of the assembly, various auxiliary members such as an oil tank can be dispersed and mounted on the assembly, and the engine unit is reduced in size. .

According to the fourth aspect of the invention, since the auxiliary member is a wheel case covering at least a part of the flywheel, the wheel case can be easily attached to the assembly.

According to the fifth aspect of the present invention, since the auxiliary member is a member that forms a part of the oil passage to the oil pump for the four-stroke engine, the structure of the oil pipe is simplified, and the number of piping steps is reduced. I do.

According to the sixth aspect of the present invention, since the auxiliary member is a member forming a part of an oil tank of a dry sump type four-cycle engine, a separate oil tank is not required, and the engine unit can be reduced in size. Become.

[Brief description of the drawings]

FIG. 1 is a side view of a small boat equipped with a dry sump lubricated four-stroke engine unit according to the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

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

FIG. 4 is a sectional view of an engine body according to the present invention.

FIG. 5 is an exploded plan view of a lubricating oil tank and a lid according to the present invention.

FIG. 6 is a rear view of the dry-sump lubricated four-stroke engine unit according to the present invention with the lubricating oil tank removed.

FIG. 7 is a rear view of the dry sump lubricated four-stroke engine unit according to the present invention with a lid for a lubricating oil tank removed.

FIG. 8 is a sectional view of a lubricating oil tank according to the present invention.

FIG. 9 is a perspective plan sectional view of a second breather chamber according to the present invention.

FIG. 10 is an exploded perspective view of an engine unit according to the present invention.

FIG. 11 is a configuration diagram of a mount mounting according to the present invention.

FIG. 12 is a rear view of a dry sump lubricated four-cycle engine unit (modified example) according to the present invention.

FIG. 13 is a rear view of the dry sump lubricated four-stroke engine unit (modified example) according to the present invention with the lubricating oil tank removed.

FIG. 14 is a rear view of the dry sump lubricated four-stroke engine unit (modified example) according to the present invention with the lubricating oil tank lid removed.

[Explanation of symbols]

3… 4 cycle engine unit, 8… Mount, 10
... Engine body, 11 ... Half crankcase (crankcase), 12 ... Cylinder block, 15 ... Crankshaft, 22 ... Tank mounting packing surface as coupling surface, 51 ... Flywheel, 52 ... Wheel case as auxiliary member 58: engine hanger, 59: coupling surface,
61: lubricating oil tank (oil tank) as an auxiliary member; 61e, 61f: suction oil passage and discharge oil passage as oil passage; 63: lid; 64: return pump as oil pump; C: assembly.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F01M 1/02 F01M 1/02 A F02B 77/00 F02B 77/00 C Q

Claims (6)

[Claims] 1. A coupling surface is formed on a side of an assembly consisting of a cylinder block and a crankcase, and on a surface orthogonal to a horizontally extending crankshaft, and an auxiliary member is attached to the coupling surface, and an auxiliary member is attached to the coupling surface. An engine unit, wherein a member is provided with a mount for supporting the assembly. 2. A connecting surface is formed on a side of an assembly including a cylinder block and a crankcase and on a surface orthogonal to a horizontally extending crankshaft, and an auxiliary member is attached to the connecting surface, and an auxiliary member is attached to the connecting surface. An engine unit, wherein an engine hanger for suspending the assembly is provided in an upper half of the member. 3. The coupling surface is on both sides of the assembly,
The engine unit according to claim 1 or 2, wherein the auxiliary member is attached to each coupling surface. 4. The engine unit according to claim 1, wherein the auxiliary member is a wheel case that covers at least a part of a flywheel. 5. The engine according to claim 1, wherein the engine unit is a four-stroke engine, and the auxiliary member is a member that forms a part of an oil passage to an oil pump. unit. 6. The engine unit according to claim 1, wherein the engine unit is a dry sump type four-cycle engine, and the auxiliary member is a member forming a part of an oil tank.