JP2001336425A - Outboard motor mounted with four-cycles v-type engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outboard motor mounted with a water-cooled four-cycles V-type engine designed to be compact. SOLUTION: The engine is provided with a cylinder head 4, a cylinder block 5 and a crankcase 6. An inlet port 21 is formed in the cylinder head in the engine 2 wherein a V-bank 7 is formed between the cylinder blocks by means of the V-type arrangement of a pair of cylinder blocks. Then the inlet manifolds 19 are arranged in the space 25 formed by the V-bank 7 and an engine cover. The inlet manifold and a combustion chamber 20 formed in the junction located between the cylinder head and the cylinder block are communicated by the inlet port 21. The inlet manifolds are connected to a throttle body 17 arranged on the upside of the engine 2. Then a silencer 16 is arranged in the space 26 formed by the cylinder block, the crankcase and the engine cover. Thus the silencer and the throttle body 17 are connected by a connecting tube 18.

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 a four-stroke V-type engine, and more particularly to an outboard motor equipped with a four-stroke V-type engine which is characterized by a layout of intake and exhaust devices.

[0002]

2. Description of the Related Art In order to make an engine compact, there is a V-type engine in which a pair of cylinder blocks are arranged so as to face a V-type. In particular, since outboard motors are required to be lightweight and compact, V-type engines are increasingly used.

In an outboard motor, since an engine and an intake / exhaust device are housed in an engine case, various attempts have been made particularly for the layout of the intake / exhaust device.

[0004] As one example, Japanese Patent Application Laid-Open No. 6-264775
There is a structure of a suction / exhaust device disclosed in Japanese Patent Application Laid-Open Publication No. H11-209,873. The layout of this intake / exhaust device is such that an exhaust port is formed toward the inside of the V bank, an exhaust passage communicating with the exhaust port is provided below the V bank, and an intake port and this intake port are provided outside the V bank. An intake passage communicating with the port is provided.

[0005]

However, in the above-described layout of the intake / exhaust device, the intake device protrudes in the width direction of the engine.

In addition, in the above-described intake / exhaust device layout, it is difficult to replace the spark plug, and the maintenance is poor.

The present invention has been made in view of the above circumstances, and has as its object to provide an outboard motor equipped with a compact 4-cycle V-type engine.

Another object of the present invention is to provide an outboard motor equipped with a four-cycle V-type engine with improved maintainability.

[0009]

According to the present invention, there is provided an outboard motor equipped with a four-cycle V-type engine according to the present invention. It has a crankcase, is installed on an engine holder, its periphery and upper part are covered by an engine cover, a crankshaft is arranged in the crankcase, and a piston is inserted in a cylinder formed in the cylinder block. By inserting the piston and the crankshaft so as to be slidable in a direction perpendicular to the crankshaft and connecting the piston and the crankshaft, the reciprocating stroke of the piston is converted into the rotational movement of the crankshaft, while the pair of cylinder blocks is
In an outboard motor equipped with a water-cooled 4-cycle V-type engine in which a V bank is formed between these cylinder blocks by disposing them in a mold, an intake port is formed in the cylinder head, and the V bank and the engine are formed. An inlet manifold is arranged in a space formed by the cover, and the inlet manifold is connected to a combustion chamber formed at a joint between the cylinder head and the cylinder block through the intake port. In addition to being connected to the throttle body disposed above the engine, a silencer was disposed in a space formed by the cylinder block, the crankcase, and the engine cover, and the silencer and the throttle body were connected by a connection pipe. Things.

[0010]

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

FIG. 1 is a longitudinal sectional view of an engine of an outboard motor to which the present invention is applied, and FIG. 2 is a sectional view taken along the line II-II of FIG. FIG. 3 is a sectional view of FIG.
It is sectional drawing which follows the I line. As shown in FIGS. 1 to 3, the engine 2 of the outboard motor 1 is, for example, a water-cooled four-cycle V-type four-cylinder engine, and is installed on an engine holder 3. The engine 2 is configured by combining a cylinder head 4, a cylinder block 5, a crankcase 6, and the like. A V bank 7 is formed between the cylinder blocks 5 by disposing a pair of cylinder blocks 5 in a V shape.
The engine 2 is covered around and above by the engine cover 8.

A crankshaft 9 vertically arranged in a crankcase 6 of the engine 2 so as to face a vertical direction.
Are rotatably supported. A cylinder 10 is formed in the cylinder block 5. A piston 11 is slidably inserted into the cylinder 10 in a direction perpendicular to the crankshaft 9, and the piston 11 and the crankshaft 9 are connected by a connecting rod 12. And piston 1
One reciprocating stroke is converted into a rotational movement of the crankshaft 9.

The engine 2 includes an intake device 13 and an exhaust device 14. The intake device 13 includes an introduction pipe 15 for introducing fresh air from the outside, a silencer 16 for reducing air introduction noise and pulsation, and a connection pipe 1 for connecting the silencer 16 and a throttle body 17 for adjusting the amount of air.
8. Air from the throttle body 17 is supplied to each cylinder 10
And an intake port 2 formed in the cylinder head 4 and communicating with a combustion chamber 20 formed at a joint between the cylinder head 4 and the cylinder block 5 and the inlet manifold 19.
1

The exhaust device 14 includes the cylinder head 4
Exhaust port 22 formed within and communicating with the combustion chamber 20
And an exhaust passage 23 formed in the cylinder block 5 and communicating with the exhaust port 22. The left side of the center of the engine 2 in FIG. 2 mainly shows the exhaust device 14, and the right side shows the intake device 13.

As shown in FIG. 2, the exhaust passage 23 is formed in the innermost valley 24 of the V bank 7,
That is, the inlet manifold 19 is vertically arranged in the space 25 formed by the V bank 7 and the engine cover 8. As shown in FIG. 1, the inlet manifold 19 extends upward, and its upstream end is located above the engine 2 and downstream of the throttle body 17 arranged between the V banks 7 in plan view (see FIG. 2). Connected to.

A silencer 16 and an introduction pipe 15 are arranged in a space 26 formed by the cylinder block 5, the crankcase 6, and the engine cover 8. And the connecting pipe 1 arranged on one cylinder block 5
8 connects the upstream side of the throttle body 17 and the downstream side of the silencer 16.

The camshaft 2 is provided in the cylinder head 4.
7, a valve train 30 including an intake valve 28, an exhaust valve 29, and the like. A spark plug 31 is screwed to the center of the combustion chamber 20 from outside the V bank 7 of the cylinder head 4. Further, a fuel injector 32 is mounted from the inside of the V bank 7, and is arranged so as to inject fuel into the intake port 21 on the upstream side of the intake valve 28. Note that the fuel injector 3
When a carburetor is provided instead of the carburetor 2, the carburetor is disposed at a connection between the inlet manifold 19 and the intake port 21 (not shown).

Next, the operation of the present embodiment will be described.

The exhaust passage 23 of the exhaust device 14 is
Conventionally, the inlet manifold 19 that forms the intake device 13 is formed in the innermost valley portion 24 of the bank 7, and is disposed outside the space 25, that is, in the space 25 formed by the V bank 7 and the engine cover 8. The intake device 13 does not protrude in the width direction of the engine 2 as in the case of the above, and the engine 2 can be made compact.

Further, as in the prior art, an intake port 21 and an inlet manifold 19 communicating with the intake port 21 are provided outside the V bank 7, that is, in a space 26 formed by the cylinder block 5, the crankcase 6, and the engine cover 8. This space 26 is not provided.
Can be used effectively, and the silencer 16 and the introduction pipe 15 can be arranged.

Similarly, since the spark plug 31 can be mounted from the outside of the V bank 7 of the cylinder head 4, the replacement of the spark plug 31 is facilitated and the maintainability is improved.

[0022]

As described above, according to the outboard motor equipped with the four-cycle V-type engine according to the present invention, the intake device does not protrude in the width direction of the engine, and the engine can be made compact. .

Further, replacement of the spark plug is facilitated, and maintenance is improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an engine of an outboard motor showing one embodiment of an outboard motor equipped with a 4-cycle V-type engine according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Outboard motor 2 4 cycle V-type engine 4 Cylinder head 5 Cylinder block 6 Crankcase 7 V bank 8 Engine cover 9 Crankshaft 10 Cylinder 11 Piston 13 Intake device 16 Silencer (intake device) 17 Throttle body (intake device) 18 Connection Pipe (intake device) 19 Inlet manifold (intake device) 20 Combustion chamber 21 Intake port (intake device) 22 Exhaust port (exhaust device) 23 Exhaust passage (exhaust device) 25 Space formed by V bank and engine cover 26 Cylinder Space formed by block and crankcase and engine cover

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 35/116 B63H 21/26 E

Claims (1)

[Claims] A cylinder block having a cylinder head, a cylinder block, and a crankcase, wherein the cylinder block is disposed on an engine holder, and its periphery and upper portion are covered by an engine cover; and a crankshaft is arranged in the crankcase. A piston is slidably inserted into a cylinder formed therein in a direction perpendicular to the crankshaft and the piston and the crankshaft are connected to convert a reciprocating stroke of the piston into a rotational motion of the crankshaft. On the other hand, in an outboard motor equipped with a water-cooled 4-cycle V-type engine having a pair of cylinder blocks arranged in a V-shape to form a V-bank between these cylinder blocks, an intake port is provided in the cylinder head. And the V bank and the An inlet manifold is arranged in a space formed by the engine cover, and the inlet manifold communicates with a combustion chamber formed at a junction between the cylinder head and the cylinder block through the intake port, while the inlet manifold is connected to the inlet manifold. In addition to being connected to the throttle body disposed above the engine, a silencer was disposed in a space formed by the cylinder block, the crankcase, and the engine cover, and the silencer and the throttle body were connected by a connection pipe. An outboard motor equipped with a four-cycle V-type engine.