JP2002235621A - Intake silencer and outboard motor having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To integrally provide a cylindrical connecting port to be connected to a throttle valve device with a cylindrical outside air intake port having a pipe elongation effect without other components except for upper/lower members. SOLUTION: This intake silencer is constituted of a box member formed by joining recessed two-slit members 3 and 4, and the cylindrical connecting port 5 for connecting an inlet passage to the member inside is integrally and outward projectingly provided in a part of one member 4 of the two-slit members. Gutter-shaped parts 4c and 5c constituting a cylindrical part by joined together are symmetrically and outward projectingly provided in both of the two-slit members and the respective members are joined together so that the cylindrical outside air intake port projecting outward in the gutter-shaped parts is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake silencer suitable for mounting on an engine of an outboard motor and an outboard motor provided with the same.

[0002]

2. Description of the Related Art As an intake silencer used for an engine of an outboard motor, a technique disclosed in Japanese Patent Application Laid-Open No. Hei 8-93433 is known. This technology consists of a flat board with multiple air horns protruding inward and a case that covers the board. The board and the case are joined and integrated to form a box-shaped body, forming an intake silencer. are doing.

[0003]

In the above prior art, an air horn constituting a connection intake passage communicating with a throttle valve device of an engine is provided on a substrate of an intake silencer so as to protrude into an inner space of the intake silencer. The outer end face of the air horn is flat, and it is difficult to connect the edge of the intake passage (intake path) of the throttle valve device to the air horn. Also, it is difficult to seal the connection portion, and secure high-precision sealing performance. It is difficult. It is also conceivable to provide an air horn in the inner space to provide a mouth-shaped connection on the outer end surface of the air horn in order to facilitate and ensure the connection with the intake passage of the throttle valve device. The structure of the substrate becomes complicated, and the production becomes complicated and troublesome.

In addition, it is necessary to provide an outside air intake in the intake silencer in addition to the connection intake passage. Conventionally, a hole is provided in a box-shaped intake silencer, but the hole has a problem in terms of intake efficiency. Therefore, it is preferable to insert a tubular member in order to obtain a pipe length effect of the outside air intake. However, according to this, the number of parts increases, and a seal between the tubular member and the main body of the intake silencer is provided. A structure is required, and also in this respect, the number of parts is increased, the structure is complicated, and the cost is disadvantageous. In addition to the above, since the intake silencer is provided on one side of the longitudinal direction of the vertical engine with the crankshaft installed vertically, the size of the outboard motor including the engine in the longitudinal direction increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object thereof is to produce a box-shaped intake silencer main body without using any separate parts.
Provided is an intake silencer integrally provided with a cylindrical connection port connected to a throttle valve device and a cylindrical outside air intake having a pipe length effect. Also, an object of the present invention is to provide an intake silencer which is easy to manufacture and has a simplified structure of an intake silencer provided with a connecting pipe and a cylindrical outside air intake. Further, the object of the present invention is to provide a connection pipe connected to the intake passage of the throttle valve device integrally with the intake silencer,
Improvement of the sealing performance between the throttle valve device and the intake passage,
Provided is an intake silencer in which the sealing performance of the intake silencer itself can be improved, and a tubular external air intake having a pipe length effect can be integrally provided without increasing the number of parts.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a first aspect of the present invention is an intake air silencer for an engine including a connection port connected to an intake passage of a throttle valve device of the engine, and an outside air intake. The intake silencer is constituted by a box-shaped member formed by joining concave plate-shaped halves, and connects the intake passage and the inside of the member to a part of one of the halves. A tubular connection port is integrally provided so as to protrude outward, and the gutter-like portion constituting the cylindrical portion is symmetrically protruded outward by abutting against both of the two members. Provided,
It is characterized in that a cylindrical outside air intake port is provided by joining the members so as to protrude outward at the gutter-like portion.

In the first aspect, the step of manufacturing the box-shaped intake silencer main body by joining two concave dish-shaped members includes:
It is possible to integrally provide a cylindrical connection port to be connected to the throttle valve device and a cylindrical outside air intake port having a pipe length effect without requiring separate parts other than the upper and lower members.

A second aspect of the present invention is characterized in that, in the first aspect, the number of the cylindrical connection ports is one and the number of the cylindrical outside air intake ports is plural. According to the second aspect, a plurality of outside air intake ports are provided for one cylindrical connection port for one intake path of the throttle valve device, which is advantageous in improving intake efficiency and reducing intake noise.

According to a third aspect of the present invention, in the first or second aspect, the split member is a member divided into upper and lower parts, and has a cylindrical connection port connected to the intake passage and a cylindrical external air intake port. Is characterized by being horizontal. According to the third aspect of the present invention, members obtained by dividing the main body of the intake silencer into two upper and lower parts are vertically overlapped and joined and integrated, so that the intake silencer can be formed while keeping the height to a minimum. In the engine of the engine, the height of the outboard motor including the engine can be suppressed as much as possible and the size can be reduced.

According to a fourth aspect, in the third aspect, the engine is a V-type multi-cylinder vertical engine in a plan view and is an engine of an outboard motor, and the intake silencer is disposed above the engine. And

According to the fourth aspect of the present invention, since the intake silencer is disposed on the upper surface of the V-type engine in plan view, the arrangement of the intake silencer can utilize the upper surface of the engine and also use the space between the V-shaped banks. Therefore, a thin large-capacity intake silencer can be arranged while keeping the height of the engine as low as possible, and the height direction of the outboard motor of the V-type multi-cylinder engine can be reduced. .

According to a fifth aspect of the present invention, there is provided an intake air silencer for an engine including a connection port connected to an intake passage of a throttle valve device of the engine, and an outside air intake, wherein a cam driven on a top surface of the engine by a crankshaft. The upper part of the shaft pulley is covered with a cover, the belt is tensioned by a tension pulley, and an intake silencer having a substantially flat bottom surface is arranged above the belt, and the left and right sides of the belt are opened.

According to the fifth aspect of the present invention, the bottom of the intake silencer has a substantially planar shape, and a space is secured between the intake silencer and the upper surface of the engine. The heat is released to the side, the heat dissipation is good, and no belt cover is required.

[0014]

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 top perspective view of the intake air silencer. In the embodiment, the intake silencer 1 is used as an intake silencer for an outboard engine, as described later, and is disposed above a 4-stroke V-type multi-cylinder vertical engine vertically mounted on a crankshaft. In the figure, the right side is the front Fr of the outboard motor, and the left side is the rear Rr.

The main body 2 of the intake silencer 1 has a flat box shape, and is formed by joining and integrating two upper and lower members 3 and 4 (upper and lower halves). The bottom is generally planar and substantially flat. One cylindrical connection port 5 that opens rearward (rearward in the propulsion direction of the outboard motor) at the middle part of the rear part of the main body 2 in the left-right direction is positioned with respect to the center line of the cylindrical intake passage of the connection port 5. And two outside air intakes 6, 6 extending obliquely rearward and outward on the left and right sides of the rear along a line inclined at an arbitrary angle. A cover part 7 extending forward extends from the front part of the flat box-shaped main body, and the cover part 7 is provided by extending the front part of the lower member 4 forward.

FIG. 2 shows a main body 2 constituting the intake silencer 1.
FIG. 3 is an exploded perspective view of FIG. The lower member 4 has a concave dish shape provided around the upright wall piece 4a. In the middle part of the rear wall piece 4b on the front side of the upright wall piece 4a in the drawing, a horizontally long and oblong cylindrical connection port 5 having a cross section whose width in the left-right direction is larger than its height is provided with a concave plate. It is provided so as to extend rearward integrally so as to communicate with the inside of the member 4 in the shape of a circle. The connection port 5
It has a length in the front-rear direction, and a rear end portion 5a is opened rearward 5c.
And an opening 5b in the upstream portion which is opened in the standing piece 4b of the member 4.
(See FIGS. 5 and 6), and the openings 5c and 5b are connected by a horizontal duct 5d.

On the left and right sides of the connection opening 5 of the rear wall piece 4b, concave grooves 4c, 4c constituting upwardly open gutter-like parts of a predetermined length so as to be directed outward are formed integrally with the member 4. ing. The concave grooves 4c, 4c are provided at the boundaries between the rear ends of the rear wall piece 4b and the rear ends of the left and right side wall pieces 4f, 4f so that the inside and the outside of the concave dish-shaped member 4 can communicate with each other. In the front half of the bottom piece 4 d of the lower member 4, a semicircular eave portion 9 bulging upward in a plan view is formed integrally with the bottom piece 4 d, and the front wall piece 4 e crosses the front part of the eave portion 9. The front wall piece 4e is continuous with the left and right side wall pieces 4f, 4f.

The connection port 5 has a rear opening 5c at the rear end 5a and a rear opening 5b at the rear wall piece 4b with the same diameter at the front as described later. The above-mentioned concave groove 4
c, 4c are open to the upper and rear portions, and both sides of the rear wall piece 4b, and communicate the inside and the outside of the lower member 4.

The upper member 3 has a symmetrical shape with the lower member 4, and hangs down from the periphery of the top piece 3d to surround the hanging piece 3a.
With a shape like an inverted dish. On the left and right sides of the rear wall piece 3b of the wall piece 3a, the concave grooves 4c, 4 of the lower member 4 are provided.
c, the upper member 3 is provided with concave grooves 3c, 3c each having a shape obtained by inverting a gutter constituting a gutter-like portion that opens downward and corresponding to c.
And projecting together. The concave grooves 3c, 3c are integrally formed so as to protrude rearward between the left and right sides of the rear wall piece 3b and the boundary between the left and right side wall pieces 3f and the front piece 3e.

The upper and lower members 3 and 4 are overlapped and joined and integrated. For example, a sealing material 2a is interposed between the upper edges 4g of the wall pieces 4a of the lower member 4, an adhesive is adhered to the edges 4g, and butted against the lower edges 3g of the wall pieces 3a of the upper member 3. The upper and lower members 3 and 4 are adhered. Instead of bonding, welding may be performed by vibration welding or the like, and bolting may be used if necessary.

As described above, the upper and lower members 3, 4 are overlapped, and the wall pieces 4a, 3a at the peripheral edges of the members 2, 4 are joined and integrated, and the flat thin box-shaped main body 2 shown in FIG. To form
The concave grooves 3c, 3c, 4c, 4c formed symmetrically by joining and integrating the upper and lower members 3, 4 are overlapped. Is formed (see FIG. 1).

As shown in FIGS. 1 and 4, the outside air intake ports 6 and 6 are arranged in a "C" shape with the connection port 5 therebetween in a plan view toward the rear, and the end faces are as shown in FIG. In the embodiment, the lower half has a rectangular concave shape, and the upper half has a substantially triangular inverted concave shape, and has an opening shape in which these are connected vertically. The connection port 5 on the cylinder extends rearward in the meantime and opens rearward,
It communicates with and is connected to an intake passage of a throttle valve device, which will be described later, and communicates with an intake muffling chamber inside the main body 2. When these upper and lower members 3 and 4 are joined and integrated, a net member 10 constituting a frame arrestor is interposed therebetween to be clamped and fixed.

FIG. 3 is a plan view of the lower member 4. When described in conjunction with FIG. 2, a holding frame portion 11 having a concave shape in a front view and having three sides, a lower side and both sides, is formed on the back side of the connection port 5 inside the rear wall piece 4 b of the lower member 4. Then, a continuous locking groove 11a is provided on three inner sides of the holding frame portion 11. The mesh member 10 is formed of a metal, for example, a stainless steel wire, and has a horizontally long rectangular plate shape in the embodiment, and its left and right edges and lower edges 10a, 10a, 10b are inserted into the locking grooves 11a of the holding frame 11 from above. The holding member 11 is sandwiched and fixed to the holding frame portion 11 by covering the holding member 12 in the form of a horizontally long cap from above the upper edge 10 c of the mesh member 10.

FIG. 4 is a plan view of the main body 2 of the intake silencer 1, and FIG. 5 is a sectional view taken along line 5-5 of FIG. As shown in FIG. 5, as described above, a semicircular eave portion 9 bulging upward from the bottom piece 4d is provided in the front half of the bottom piece 4d of the lower member 4 of the main body 2 in the width direction. And the lower member 4
Is integrally provided with a cover 7 extending forward. The ceiling 9a of the eaves section 9 and the ceiling 7a of the cover section 7 are continuous at the same level, and in the embodiment, an upwardly projecting concave portion 9b is formed at the center of the ceiling 9a of the eaves section 9 and the cover section. A ventilation opening 7b is provided in the front part of the ceiling 7a of 7.

The eaves 9 and the cover 7 formed on the bottom surface of the main body 2 absorb the interference in the height direction with respect to the belt when the intake silencer 1 is disposed above the engine, thereby avoiding it. Therefore, the demand for a smaller engine room is satisfied. Further, the belt cover can be omitted by arranging a wide intake silencer on the left and right above the belt. It constitutes a drive pulley protruding above the engine, a driven pulley of the generator, and a belt cover connecting between them. This will be described later. In the main body 2 described above, the intake silencer 13 is provided.
Is formed, and the intake muffling chamber 13 is connected to the intake passage of the throttle valve device through the connection port 5 and communicates with the outside air through the outside air intake ports 6 and 6.

FIG. 6 is an enlarged view of the main part of FIG. 5 showing the details of the holding structure of the net member 10. As shown in FIG. FIG. 7 is a sectional view taken along line 7-7 of FIG. The holding structure of the net member 10 will be described with reference to FIGS. The holding frame 11 of the mesh member 10 is
7 is provided so as to surround the left and right and lower sides of the upstream opening 5b of the connection port 5 provided on the rear wall piece 4b so as to be opposed to the intake port downstream opening 5b, as shown in FIG. Make an open concave shape. The locking groove 11a is formed inside the concave holding frame 11 in a concave shape when viewed from the front.

The mesh member 10 is provided with a locking groove 11 of the holding frame 11.
The upper and lower edges 10a, 10a and the lower edge 10b of the mesh member 10 are inserted in such a manner as to engage with each other, and the upper edge 10c of the net member 10 is protected and held by covering the pressing member 12 from above. in this way,
The mesh member 10 constituting the frame arrestor is sandwiched between the upper and lower members 3 and 4 in the process of being overlapped and joined and integrated.

FIG. 8 is a rear view of the intake air silencer 1 described above. The connection port 5 in the middle part is opened rearward, the mesh member 10 constituting the frame arrestor is provided at the back, and two outside air intake ports 6 and 6 are provided on the left and right. Can understand.

FIGS. 9 and 10 show another embodiment of the present invention. FIG. 9 is a plan view of the intake silencer and FIG.
FIG. In the present embodiment, the upper and lower members 3,
When joining and integrating the bosses 4, bosses 14... Are provided at a plurality of positions on the edges 3 g and 4 g, which are joints between the upper and lower members 3 and 4, and screws 15 are passed through the bosses 14. 3g, 4
g are screwed together and joined together. The main body 2 may be formed by screwing and integrating the upper and lower members 3 and 4 in addition to or instead of bonding or welding.

FIG. 11 is a front view showing another embodiment of the mesh member. FIG. 12 is a sectional view taken along line 12-12 of FIG. The mesh member 110 surrounds the periphery of the mesh body 110a knitted with a stainless wire or the like so as to protrude at the central portion.
10b, a net member 110 having a substantially rectangular shape in a front view is formed.

Next, as an example of an engine provided with the intake air silencer according to the present invention, an example of a V-type multi-cylinder vertical engine of an outboard motor will be described. FIG. 13 is an external perspective view of the outboard motor. The outer shape of the outboard motor 20 includes an upper engine cover 21, an under cover 22, an extension case 23, and a gear case 24. A screw 25 is provided at the rear of the gear case 24, and a stern bracket 26 is provided at a front portion between the under cover 22 and the extension case 23 so as to be pivotable about a swivel shaft 27.

FIG. 14 shows the engine cover 2 of the outboard motor 20.
1 is an enlarged view of a main part in which a part of an under cover 22 is broken and the intake silencer 1 is broken. The outside of the engine 30 and the accessories are covered with an engine cover 21 to form an engine room S. The engine 30 has a plurality of cylinders 31a.
Are arranged vertically, a cylinder head 32 arranged on the rear surface of the cylinder block 31,
Cylinder head cover 33 disposed on the rear surface, crankcase 3 disposed on the front surface of cylinder block 31
4, a cylinder block 31, a mount case 35 arranged on the lower surface of the crankcase 34, a piston 36 in the cylinder 31a, a crankshaft 37, and the like.

The mounting case 35 is provided for the under cover 22.
The extension case 38 is supported by an extension case 38, and an oil pan 39 is provided in the extension case 38. An exhaust manifold 40 connected to an exhaust port of the cylinder head 32 is connected to an exhaust pipe 41. The exhaust pipe 41 faces downward and discharges exhaust gas to below the extension case. A generator (ACG) 42 is mounted and supported on the upper part of the front surface of the crankcase 34, a drive pulley 43 driven by a crankshaft 37 is provided on the upper surface of the cylinder block 31, and a camshaft drive is provided on the upper surface of the cylinder head 32. A pulley 44 is provided.
And 44 are connected by a timing belt 46 via an intermediate tension pulley 45 to drive the camshaft.

The upper side of the camshaft drive pulley 44 is covered with a pulley cover. A tension pulley 45 in front of the camshaft pulley 44, and upper and lower drive pulleys 43 and 4.
7. The bottom of the intake silencer 1 faces above the generator pulley 48, and covers the pulleys and belts other than the camshaft pulley 44.

As shown in FIG. 16, the belt 46 is arranged by the tension pulleys 45, 45, 55 so that the width in the left-right direction is narrowed in the engine room. A space is secured between the engine 30 and the upper surface thereof. Therefore, air is discharged from the side between the upper surface of the engine and the intake silencer, and a belt / pulley mechanism having high heat dissipation can be obtained. In addition, the intake silencer eliminates the need for a cover on pulleys other than the camshaft pulley, thereby reducing the number of belt covers.

A large-diameter drive pulley 47 is coaxially connected to the drive pulley 43, and is connected to a driven pulley 48 of the generator 42 via a timing belt 49 to drive the generator 42. Behind the cylinder head cover 33, an intake manifold 50 is disposed vertically, and a throttle valve device 51 is disposed at the upper end of the intake manifold 50 so that the intake path is horizontal. Turn to the front.

The above-described intake silencer 1 is disposed above the cylinder block 31 and the crankcase 34 of the engine 30. The main body 2 of the intake silencer 1 is mounted and supported on the engine side via the mounting stays 8.
The above-described large-diameter drive pulley 47 faces below the above-mentioned eaves 9 formed on the bottom surface of the cover, and the driven pulley 48 of the generator 42 faces below the ventilation opening 7b provided on the ceiling 7a of the cover 7, and the eaves The cover 9 and the cover 7 constitute a cover member of the pulley. Accordingly, as described above, the intake silencer constitutes the cover member of the pulley and does not require a cover on the drive pulley side.

A connection port 5 provided at the rear of the main body 2 of the intake silencer 1 faces rearward, and the connection port 5 communicates via a grommet 52 with an intake passage of a throttle body constituting an intake passage of a throttle valve device 51. Connecting. The connection of the throttle valve device 51 to the intake passage is made by connecting the connection port 5 to a cylinder and projecting rearward, or by fitting a tubular portion to the intake passage. The connection with the tubular intake passage is also made by a grommet. Since the sealing is performed according to 52, the sealing property can be easily secured, and reliable and easy sealing can be performed. A cooling air intake passage 21a is provided at a front portion of the engine cover 21, and an outside air intake passage 21b is provided at an upper portion of the rear portion. The outside air is passed through a duct 53 through an internal intake opening 21c. 21 is introduced.

FIG. 15 shows the engine cover 2 of the outboard motor 20.
FIG. 2 is a plan view of the engine in which an upper portion of the engine 1 is cut away. In the embodiment, the engine 30 includes a cylinder block 31,
This is a plan view V-type engine in which 31 is arranged in a plan view V-type. In FIG. 14, three cylinders 31a are provided above and below,
By disposing this in a V-shape in plan view, in the embodiment, 4
A vertical V6 engine with a stroke V-6 was constructed.

The V bank 30a of the cylinder block 31 expands rearward, and the connection port 5 protruding toward the rear of the main body 2 of the intake silencer 1 faces the V bank 30a. 51 also faces the V-bank 30a, and the intake manifold 50 is disposed behind the V-bank 30a that is expanded. The suction pipes 50a, 50a to the cylinder heads 32, 32 are disposed in the V-bank 30a. . Reference numeral 54 in the drawing denotes a seal member that partitions the inside of the engine cover between the cylinder head side and the front.

FIG. 16 is a plan view of the engine in which the upper portion of the engine cover 21 of the outboard motor 20 shown in FIG. 15 is cut away for simplicity, and the intake muffler 1 and the intake system are removed. It is explanatory plan view. Exhaust ports 32a. Of the cylinder heads 32, 32 arranged in a V-shape in plan view. 3
An exhaust manifold 40 connected to 2a extends downward in the engine room S and is connected to an exhaust pipe 41. The exhaust pipe 41 extends downward and under the under cover 22 as shown in FIG. Under cover 2
2. Exhaust gas is discharged through the extension case 23. In the figure, a belt pulley mechanism arranged on the lower surface of the intake silencer 1 is clearly shown, and 55 is a tension pulley for adjusting the belt tension.

FIG. 17 is an enlarged longitudinal sectional view of a main part of the engine. As described above, the engine 30 includes three cylinders 31a at the top and bottom of each horizontally oriented cylinder block 31, and each of the cylinders 31a.
Are connected, and the horizontal connecting rods 31c are connected to the crankshaft 37 described above. Each cylinder 31
A combustion chamber 32b is provided on the ceiling of
6, two intake valves 57, two exhaust valves 58, each of the three combustion chambers 32b are provided with these, and for convenience of explanation, two sets of each of the three combustion chambers 32b are individually provided. Indicated.

A camshaft 59 is provided behind the cylinder head 32, and the camshaft 59 is driven by the camshaft driving pulley 44 described above. To the left and right of this,
A rocker arm shaft 60 that supports a valve rocker arm that opens and closes the exhaust valve is provided, and the outside of these is covered with a cylinder head cover 33.

FIG. 18 is a rear view of an essential part of the engine including the intake manifold 50, and shows a state where the engine cover 21 is removed. The intake manifold 50 has a large capacity, and the V bank 30a is expanded behind the engine 30.
It is located behind. The intake manifold 50 is connected to the intake valves 57 of the respective cylinders 30a of the engine 30 by three intake pipes 50a at the top and bottom, and six intake pipes 50a at the right and left, and the intake manifold 50 is a throttle valve at the upstream part. The throttle valve device 51 is connected to the device 51,
The connection member 5 is connected to the connection port 5 of the intake silencer 1 via the grommet 52, and the connection member 5 is provided with the mesh member 11 constituting the frame arrester as described above.

FIG. 19 is a top perspective view and a rear view of another embodiment of the intake air silencer. In the present embodiment, the outside air intake is changed, and other configurations are the same as those described above. Therefore, the same portions are denoted by the same reference numerals, and detailed description is omitted. The outside air intakes are cylindrical portions 206, 206 formed by closing the end surface 206a as shown in FIG.

Each of the tubular portions 206, 2 having the end face 206a closed
06 is provided with a horizontally long rectangular outside air intake 206b that is long in the left-right direction on the lower surface near the rear end. As in this embodiment, a structure in which the outside air intake port is opened downward may be used, or a structure in which the outside air intake port is opened laterally or upward.

Although the embodiment has been described in detail above, the target of the implementation of the intake silencer is not limited to the above-described V-type multi-cylinder vertical engine and the outboard motor to which the embodiment is applied. It can be adopted as an intake silencer of a cylinder vertical engine, and furthermore, a normal type engine having a horizontal cylinder.

[0048]

According to the present invention, the following effects are exhibited by the above configuration. A first aspect of the present invention relates to an engine intake silencer including a connection port connected to an intake passage of a fuel supply device for the engine, and an outside air intake port, wherein the intake silencer is a concave plate-shaped split member. And a cylindrical connection port for connecting the intake passage and the inside of the member is provided integrally with a part of one of the two members so as to protrude outward. , A gutter-like part constituting a cylindrical part is provided so as to project symmetrically outward by abutting on both of the two members,
By joining the members, a cylindrical outside air intake port was provided to protrude outward at the gutter-like portion.

According to the first aspect, in the step of manufacturing the box-shaped intake silencer body by joining two concave dish-shaped members,
It is possible to integrally provide a cylindrical connection port to be connected to the throttle valve device and a cylindrical outside air intake port having a pipe length effect without requiring separate parts other than the upper and lower members. An air intake silencer having a cylindrical connection port and a cylindrical outside air intake can be easily manufactured without separately assembling a cylindrical connection port and a cylindrical outside air intake member. Since it is not required, the number of parts can be reduced, which is advantageous in cost.

Further, the main body of the intake silencer is formed by dividing the body into a concave dish shape, and a cylindrical connection port is formed integrally with one of the members.
In addition, the gutter-like portion constituting the half of the outside air intake is integrally formed, and the gutter-like portion constituting the half of the outside air intake is integrally molded with the other member. Is simple, and the half body of the intake silencer having the cylindrical connection port and the cylindrical outside air intake can be easily formed. Subsequent manufacture of the air intake silencer also involves simply joining the members to each other by means such as bonding or screwing, so that an air intake silencer having a cylindrical connection port, outside air, and an air inlet can be easily manufactured. In addition, since the cylindrical connection port and the cylindrical outside air intake port are formed integrally with the main body of the intake silencer and extend outward,
The connection port of the intake silencer itself and the outside air intake port are also excellent in terms of sealing performance, and the connection port that connects to the intake path of the throttle valve device has a cylindrical shape that protrudes outward. It can be easily and reliably connected to the battery and has good sealing properties.

According to a second aspect, in the first aspect, the number of the cylindrical connection ports is one, and the number of the cylindrical outside air intake ports is plural.

According to the second aspect, in addition to the effect of the first aspect, a plurality of outside air intake ports are provided for one cylindrical connection port for one intake passage of the throttle valve device.
An advantageous and effective intake silencer can be obtained which is advantageous for improving the intake efficiency of the throttle valve device and reducing the intake noise of the intake silencer.

According to a third aspect, in the first or second aspect, the split member is a member which is divided into upper and lower parts, and has a cylindrical connection port connected to the intake passage and a cylindrical external air intake port. Is characterized by being horizontal.

According to a third aspect of the present invention, in addition to the effects of the first or second aspect, members obtained by dividing the main body of the intake silencer into two upper and lower parts are superimposed on each other and joined and integrated to form a cylindrical connection port, a cylindrical part. Since the outside air intake port is horizontal, the connection port of the intake silencer and the external air intake port do not face up and down, and can be formed while minimizing the height of the intake silencer.In an outboard motor engine, The height of the outboard motor including the engine can be suppressed as much as possible and the size can be reduced.

According to a fourth aspect, in the third aspect, the engine is a V-type multi-cylinder vertical engine in a plan view and is an engine of an outboard motor, and the intake silencer is disposed above the engine.

According to the fourth aspect of the present invention, since the intake silencer is disposed on the upper surface of the V-type engine in plan view, the intake silencer can be disposed by utilizing the upper surface of the engine, and the V-type bank can be disposed between the V-type banks. This is advantageous in terms of space of an outboard motor having a limited outer dimension. In addition, a thin large-capacity intake silencer can be arranged while keeping the height of the engine as low as possible, and the height direction of the outboard motor of the V-type multi-cylinder engine can be made as small as possible. be able to.

According to a fifth aspect of the present invention, there is provided an intake air silencer for an engine having a connection port connected to an intake passage of a throttle valve device of the engine, and an outside air intake port, wherein a cam driven on a top surface of the engine by a crankshaft. The upper portion of the shaft pulley was covered with a cover, the belt was tensioned with a tension pulley, and an intake silencer having a substantially flat bottom surface was disposed above the belt, and the left and right sides of the belt were opened.

According to a fifth aspect of the present invention, the intake silencer is a box-like body, the bottom surface is substantially flat, the left and right sides of the belt are open, and the belt is brought sufficiently inside the box area by a tension pulley. Therefore, compared with the conventional belt cover, which collects the hot air around the upper part of the engine, the hot air is released from the left and right open parts. It is.

[Brief description of the drawings]

FIG. 1 is a top perspective view of an intake silencer.

FIG. 2 is an exploded perspective view of a main body constituting the intake silencer.

FIG. 3 is a plan view of a lower member of the intake silencer main body.

FIG. 4 is a plan view of a main body of the intake silencer.

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

FIG. 6 is an enlarged view of a main part of FIG. 5 showing details of a holding structure of the net member;

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6;

FIG. 8 is a rear view of the intake silencer.

FIG. 9 is a plan view of an intake silencer according to another embodiment of the present invention;

10 is a rear view of the intake silencer shown in FIG. 9;

FIG. 11 is a front view showing another embodiment of the net member.

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

FIG. 13 is an external perspective view of the outboard motor.

FIG. 14 is an enlarged view of a main part in which an engine cover and an under cover of the outboard motor are partially broken, and an intake silencer is broken.

FIG. 15 is a plan view of the engine in which an upper portion of an engine cover of the outboard motor is cut away.

16 is an explanatory plan view of the engine shown in FIG. 15, in which an intake silencer and an intake system are removed from a plan view of the engine in which an upper portion of an engine cover is cut away.

FIG. 17 is an enlarged longitudinal sectional view of a main part of an engine.

FIG. 18 is a rear view of the essential parts of the engine including the intake manifold, with the engine cover removed.

FIG. 19 is a top perspective view of another embodiment of the intake silencer.

FIG. 20 is a rear view of the intake silencer of FIG. 19;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outboard motor, 2 ... Intake silencer, 3, 4 ... Upper and lower members, 3c, 4c ... Gutter part, 5 ... Connection port, 6 ... Outside air intake, 30 ... Engine, 44 ... Camshaft pulley, 44a ... Camshaft pulley cover 4
5, 55 ... tension pulley.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02B 67/00 F02B 67/06 G 67/06 A F02M 35/16 Z F02M 35/16 B63H 21/26 G

Claims (5)

[Claims] An intake muffler for an engine, comprising: a connection port connected to an intake passage of a throttle valve device of the engine; and an outside air intake, wherein the intake muffler has a concave dish-shaped halved shape. It is composed of a box-shaped member in which members are joined, and is integrated with a part of one of the two members so that a cylindrical connection port connecting the intake passage and the inside of the member protrudes outward. It is provided so as to project symmetrically outwardly the gutter-like portion constituting the cylindrical portion by abutting against both of the two members,
An intake air silencer, comprising: a cylindrical external air intake port that projects outward at the gutter-like portion by joining the respective members. 2. The intake air silencer according to claim 1, wherein the number of the cylindrical connection ports is one, and the number of the cylindrical outside air intake ports is plural. 3. The split member is a member which is divided into upper and lower parts, and a cylindrical connection port connected to the intake passage and a cylindrical external air intake port are laterally oriented. The intake silencer according to claim 1 or 2, wherein 4. The engine according to claim 3, wherein the engine is a V-type multi-cylinder vertical engine in plan view and is an engine of an outboard motor, and the intake silencer is disposed above the engine. An intake silencer used for the engine of the outboard motor described in the above. 5. An intake silencer for an engine, comprising a connection port connected to an intake passage of a throttle valve device of the engine, and an outside air intake port, wherein a camshaft pulley driven by a crankshaft is provided on an upper surface of the engine. The cover is covered with a cover, tension is applied to the belt by a tension pulley, and an intake silencer having a substantially flat bottom surface is disposed above the belt, and the left and right sides of the belt are opened. Machine.