JP3058294B2 - Exhaust control device for vehicle internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust control device for an internal combustion engine for a vehicle, and more particularly to an exhaust control device capable of reducing exhaust noise when the vehicle stops or the engine warms up. About.

[0002]

2. Description of the Related Art As a conventional exhaust control system for an internal combustion engine, for example, one described in Japanese Utility Model Laid-Open Publication No. 50-46814 is known. In this exhaust control device, an exhaust throttle valve having a normally closed leaf valve is interposed in an exhaust pipe, and the exhaust throttle valve is provided with means for closing during low load operation such as idling operation.

[0003]

However, in the above-mentioned conventional exhaust control apparatus, the throttle valve is closed only when the engine is operated under a low load, that is, when the opening of the throttle valve is small. When the opening of the valve is relatively large, for example, at the time of warm-up start, the flow of exhaust gas cannot be reduced, and there is a problem that the exhaust sound becomes loud.

Further, the above-described exhaust control device adjusts the opening of the exhaust throttle valve only depending on the operating state of the engine.
Exhaust sound cannot be reduced when the vehicle is stopped at midnight or early morning, and the driver has to use nerves for surroundings. The present invention has been made in view of the above-described problems, and it is possible to narrow the exhaust passage even when the engine is operating at a relatively high output. An object of the present invention is to provide an exhaust control device that can be reduced in size.

[0005]

To achieve the above object, according to an aspect of, such an exhaust control apparatus according to the invention of claim 1, the self
In a vehicle internal combustion engine mounted on a motorcycle, an internal combustion engine
Exhaust throttle with adjustable opening in the exhaust passage for exhausting Seki exhaust
The exhaust throttle valve is installed on a motorcycle stand.
Linked with the rotation, the exhaust throttle valve when using this stand
The opening degree of the exhaust passage is reduced.

[0006]

According to the first aspect of the present invention, the exhaust control device interlocks the rotation of the stand with the rotation of the exhaust throttle valve.
The exhaust noise can be reduced by narrowing the exhaust passage when driving or stopping.
You.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 11 show an exhaust control apparatus according to an embodiment of the present invention. FIG. 1 is a side view of a motorcycle, and FIG.
3 is an enlarged plan view around the handle grip, FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2, FIG. 4 is a side view of the exhaust system, FIG. 5 is a cross-sectional view of the exhaust pipe, and FIG. FIG. 7 is a partially enlarged cross-sectional view of the exhaust pipe, FIGS. 8 and 9 are cross-sectional views of the exhaust pipe, and FIGS. 10 and 11 are views showing another embodiment of the main part, respectively. .

In FIG. 1, reference numeral 11 denotes a main frame of a motorcycle on which an engine 13 is suspended.
The head tube 12 is fixedly provided at the front end, and the rear wheel 15 is suspended by the swing arm 14 at the rear end. A front wheel 16 is supported on the head tube 12 by a front fork 17 so as to be steerable by a steering handle 18. Reference numeral 70 denotes a stand (stopping device) supported swingably at a lower portion of the main frame 11.
Is standing when stopped.

The steering handle 18 is a handle pipe 18a.
2 are provided with grips 18b at both ends thereof. As shown in FIG.
A choke lever (start-up warm-up device) 19 is attached near b. Choke lever 19 is handle pipe 1
The inner member 20 is rotatably fitted to the inner member 8a and protrudes in the radial direction integrally with the inner member 20.

As shown in FIG. 3, an outer member 21 is rotatably fitted on the outer periphery of the inner member 20. The inner member 20 is provided with a projection 20a, the outer member 21 is formed with a long hole 21a in the circumferential direction, and the inner member 20 and the outer member 21 are inserted into the long hole 21a through the protrusion 20a within a predetermined angle range. A relative displacement of θ is allowed. Although a detailed description is omitted, a click mechanism 69 having a ball 69a is provided between the inner member 20 and the outer member 21.

[0013] One end of a muting cable 22 is locked to the inner member 20, and one end of a choke cable 23 is locked to the outer member 21.
The muting cable 22 is connected to the butterfly valve of the exhaust pipe, and the choke cable 23 is connected to the engine 1.
3 (see FIG. 4).

The above-described choke lever 19 is normally used in FIG.
As shown by a solid line, the projection 20a of the inner member 20 is located at the upper end of the elongated hole 21a of the outer member 21 in the drawing. When the choke lever 19 is operated clockwise in the drawing as indicated by the imaginary line, the inner member 20 first rotates, and when the projection 20a contacts the lower end of the elongated hole 21a, the outer member 21 rotates. Therefore, only the muting cable 22 is pulled in a range where the rotation angle of the choke lever 19 is small, and when the rotation angle of the choke lever 19 exceeds the angle corresponding to the length of the elongated hole 21a, the choke cable 23 is turned off. Pulled.

The above-mentioned choke lever 19 is operated at a small operating angle smaller than a predetermined angle.
In order to pull the muting cable 22 and the choke cable 23 at a large operation angle, the inner member 20 and the outer member 21 which are allowed to move relative to each other by a predetermined angle θ are used. The lever 19 can be connected to each cable 22, 23 via a mechanism as shown in FIG. 10 or a mechanism as shown in FIG.

The mechanism shown in FIG.
The disk 68 is rotatably supported on the disk 6 and the like.
8 shows the main cable 67 connected to the choke lever 19
Lock one end of And, on the disk 68,
The muting cable 22 and the choke cable 23 are locked apart from each other in the radial direction.

The mechanism shown in FIG. 11 is such that a central portion is rotatably mounted on a main frame 11 or the like and a lever member 6 is provided.
6 is provided, and the end of the main cable 67 connected to the choke lever 19 is locked to one end of the lever member 66. The other end of the lever member 66 is engaged with the end of the choke cable 23 via a spring 65, and the end of the muting cable 22 is engaged at a position further away from the center of rotation. Is to stop it. 10 and 11, even if the operation angle of the choke lever 19 is small, only the muting cable 22 can be pulled, and if the operation angle of the choke lever 19 is large, both cables 22 and 23 can be pulled.

The engine 13 has four cylinder portions 13a.
And is mounted with the cylinder portion 13a obliquely upward and forward. These cylinder parts 13a
Are connected to a carburetor 24 and an air cleaner 25 via an intake pipe 31 (see FIG. 4) at an upper portion, respectively.
An exhaust pipe 26 is connected to a lower portion of 3a. The above-described intake pipe 31
Accommodates a throttle valve, and the choke cable 23 is connected to the throttle valve as described above.

In FIG. 1, reference numeral 27 denotes a fuel tank; 28, a seat attached by a seat frame 29;
0 is a cushion unit interposed between the swing arm 14 and the seat frame 29, and 64 is a radiator.

As shown in FIGS. 4 and 5, each of the exhaust pipes 26 extends rearward below the engine 13 and is connected to the muffler 34 via a first collecting pipe 59a and a second collecting pipe 59b. Connecting. In these collecting pipes 59a and 59b, passages 33a and 33b are vertically separated by a partition plate 32a. Reference numeral 63 denotes a dummy cover.

An exhaust pipe 26 extending from the first cylinder portion 13a (# 1) in the ignition sequence and an exhaust tube 26 extending from the third cylinder portion 13a (# 3) in the ignition sequence are provided in the passage 33a. Similarly, an exhaust pipe 26 extending from the second cylinder part 13a in the ignition order and an exhaust pipe 26 extending from the fourth cylinder part 13a in the ignition order are formed in the passage 33b. And open and gather. The passages 33a and 33b of the collecting pipe 32 open to the muffler 34,
After the exhaust pipes 26 of the first, third, and second and fourth cylinders having different ignition timings assemble in the passages 33a and 33b, all of the exhaust pipes assemble in the muffler 34.

An elliptical interference hole 32b having a major axis in the longitudinal direction of the pipe is formed in the above-mentioned partition plate 32a, and the butterfly valve 3 is formed at a position corresponding to the interference hole 32b inside.
5 are provided. The butterfly valve 35 has a disk shape having a diameter substantially equal to the minor diameter of the interference hole 32b, and a central portion is fixed to the support shaft 36, and is supported via the support shaft 36 so as to close the interference hole 32b. As shown in FIG. 5, when the butterfly valve 35 closes the interference hole 32b, a crescent-shaped gap is formed at both ends in the pipe longitudinal direction of the interference hole 32b to communicate the passages 33a and 33b.

As shown in FIGS. 8 and 9, both ends of the support shaft 36 are rotatably inserted through the pipe wall of the collecting pipe 59, and a click mechanism 37 is provided on the right side of the drawing. The wheel 38 is fixed to the right end protruding outside 59.
A spring 39 is compressed between the wheel 38 and the outer wall of the collecting pipe 32, and the end of the muting cable 22 described above is locked to the periphery. The wheel 38 is rotated by the operation of the choke lever 19, and the support shaft 36, that is, the butterfly valve 35, rotates integrally with the wheel 38.
Reference numeral 60 denotes a stopper for the wheel 38.

The click mechanism 37, as shown in FIG.
Four grooves 36a are formed in a part of the support shaft 36 in the longitudinal direction at equal intervals in the rotation direction, and a bush 61 in which four grooves 32c are formed corresponding to the grooves 36a is provided in the collecting pipe 59. It is configured with rubber 40 interposed between 36a and 32c. In the click mechanism 37, the rubber 40 is deformed corresponding to the groove 36a by the rotation of the support shaft 36, and a click feeling is generated.

In the exhaust control apparatus of this embodiment, the butterfly valve 35 normally closes the interference hole 32b of the partition plate 32a as shown in the imaginary line of FIG. 5 and FIG. For this reason, the exhaust gas discharged from the engine 13 flows into the muffler 34 from each exhaust pipe 26 through the passages 33a and 33b of the collecting pipe 59, and is discharged from the muffler 34. Here, when the exhaust gas flows into the passages 33a and 33b and gathers, they interfere with each other and are silenced.
The sound is muted by interfering through the gaps before and after.

On the other hand, when the choke lever 19 is operated within the range of a predetermined angle, the butterfly valve 35 rotates together with the support shaft 36, and as shown in FIGS. , 33b are closed. Therefore, the exhaust noise radiated to the outside can be reduced.

When the engine 13 is to be warmed up, when the choke lever 19 is operated further, the outer member 21 also rotates and the choke cable 23 is pulled, and the throttle valve is opened as is well known. Then, also at this time, as described above, the muting cable 2
2 is also pulled, and the butterfly valve 35 is moved to the passage 33a.
Since 33b is closed, exhaust noise during warm-up operation can be reduced.

FIG. 12 shows a second embodiment of the present invention and is a schematic side view of an exhaust system. In addition, in this embodiment and each embodiment described later, the same portions as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the second embodiment, a butterfly valve 35 is provided.
Negative pressure actuator 4 as an actuator for driving
1 is provided near the collecting pipe 59 and the negative pressure actuator 41 is provided.
Is connected to the butterfly valve 35, that is, the wheel 38 described above, by a cable 42 or the like. Negative pressure actuator 4
Reference numeral 1 denotes a pipe 43 connected to an output port of an electromagnetic control valve 44, and operates with a negative pressure supplied from the control valve 44.

The control valve 44 is connected by a pipe 45 to the air cleaner 25 and by a pipe 46 to the intake pipe 31. The control valve 44 is connected to a switch box 47 and is controlled by the switch box 47 to supply a negative pressure to the negative pressure actuator 41. In addition,
Since the control valve 44 can be a known one, the description is simplified.

The switch box 47 is provided with switches such as a choke switch 19a and a muting switch 19b. The switch box 47 is operated when the vehicle is stopped or the engine is warmed up during start-up. The switch valve 47 is energized to supply a negative pressure to the negative pressure actuator 41 by energizing the control valve 44. Increase the air-fuel ratio by narrowing the passage.

Also in this embodiment, when the choke switch 19a is operated, the passages 33a and 33b are closed by the butterfly valve 35 disposed between the exhaust manifold 59 of the engine and the muffler 34, and the gas is radiated to the outside. Exhaust noise can be reduced. Choke switch 19a for driving the throttle valve and muting switch 19b for reducing the exhaust noise
Are separately provided, so that the exhaust noise can be reduced not only during the warm-up operation but also during stopping according to the surrounding conditions.

FIGS. 13 to 15 show a third embodiment of the present invention. FIG. 13 is a schematic side view of an exhaust system, FIG. 14 is a sectional view of a main part, and FIG. It is sectional drawing of a part. This embodiment uses a control valve 48 that can be manually operated.
Are connected to a muting lever 19c by a muting cable 22.

As shown in FIGS. 14 and 15, the control valve 48 has a communication hole 51 in a housing 49.
a is formed, and the valve seat member 5 is provided.
The plunger 50 is housed so that the one communication hole 51a can be closed. The valve seat member 51 is configured by assembling a rubber diaphragm 53 and a retainer member 54, and is urged by a spring 55 toward the plunger 50.

The housing 49 is provided with a valve seat member 51.
Port 4 communicating with negative pressure actuator 41 on one side of
9a and the port 49b communicating with the air cleaner 25,
Port 4 connected to intake pipe 31 on the other side of valve seat member 51
9c is formed. These ports 49a, 49b communicate with each other when the plunger 50 closes the communication hole 51a of the valve seat member 51 (see FIG. 15), and the ports 49a, 49c communicate when the plunger 50 is separated from the valve seat member 51 (FIG. 14). ).

The plunger 50 has a drive arm 56 at the right end.
, And slides in the housing 49 by the swing of the drive arm 56 to open and close the communication hole 51a. Drive arm 56
Is pivoted at the center, one end is connected to the plunger 50 and the muting cable 22 is locked at the other end as described above. The drive arm 56 swings by operating the muting lever 19c.

In this embodiment, normally, the control valve 48 communicates with the ports 49a and 49b, the negative pressure actuator 41 does not operate, and the butterfly valve 3
5 keeps the interference hole 32b closed. And
When the muting lever 19c is operated, the control valve 48 is operated, and when the drive arm 56 is as shown in FIG. 14, a negative pressure is supplied to the negative pressure actuator 41,
The negative pressure actuator 41 drives the butterfly valve 35 to close the passages 33a and 33b. Further, when the engine rotation increases, the negative pressure of the butterfly valve 35 to the negative pressure actuator 41 decreases, and the butterfly valve 35 returns to the direction of opening the exhaust path. Therefore, if the muting lever 19b is operated, exhaust noise during idling operation with a low engine speed can be reduced. The rest is the same as the above-described second embodiment, and a description thereof will be omitted.

FIG. 16 shows an exhaust control apparatus according to a fourth embodiment of the present invention, and is a partially enlarged side view of a motorcycle. In this embodiment, the end of the muting cable 22 is engaged with the base end of a stand 70 as a stop device, and the opening and closing of the butterfly valve 35 is linked to the operation of the stand 70.

In this embodiment, when the stand 70 is standing, that is, when the motorcycle is stopped using the stand 70, the butterfly valve 35 is connected to the passage 33.
a, 33b are closed. For this reason, exhaust noise can be reduced when parking or stopping.

In the present invention, the stand 70 is exemplified as a stop device, and the butterfly valve 35 is operated in conjunction with the operation of the stand 70. The invention can be achieved. Further, the engine is not limited to the one illustrated in the present embodiment, and the same applies to a plurality of cylinders such as a single cylinder and a V-type multi-cylinder.

[0039]

As described above, according to the first aspect of the present invention, the rotation of the stand of the motorcycle interlocks with the rotation of the stand.
Since the exhaust passage is closed, when using the stand
Exhaust noise can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle to which an exhaust control device for a vehicle internal combustion engine according to a first embodiment of the present invention is applied.

FIG. 2 is a plan view showing a part of a steering handle of the motorcycle.

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

FIG. 4 is a side view of an exhaust system of the motorcycle.

FIG. 5 is a sectional view of an exhaust pipe of the exhaust system.

FIG. 6 is a partially enlarged sectional view of the exhaust system.

FIG. 7 is a partial sectional view of the exhaust system.

FIG. 8 is a cross-sectional view of the exhaust system.

FIG. 9 is a cross-sectional view of the exhaust system in a state different from FIG. 8;

FIG. 10 is a diagram showing another embodiment of a part of the exhaust control device;

FIG. 11 is a view showing another embodiment of the same part.

FIG. 12 is a schematic side view of an exhaust system of an exhaust control device according to a second embodiment of the present invention.

FIG. 13 is a schematic side view of an exhaust system of an exhaust control device according to a third embodiment of the present invention.

FIG. 14 is a sectional view of main components of the exhaust control device.

FIG. 15 is a sectional view of the main part in a state different from FIG. 12;

FIG. 16 is an enlarged side view of a main part of an exhaust control device according to a fourth embodiment of the present invention.

[Description of Signs] 13 ・ ・ ・ Engine 19 ・ ・ ・ Choke Lever 19a
... Choke switch, 19b ... Muting switch, 19c ... Muting lever, 22 ... Muting cable, 26 ... Exhaust pipe, 32 ... Collecting pipe, 35 ... Butterfly valve , 41: negative pressure actuator, 44, 48: control valve, 7
0 ... Stand (stop equipment).

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-128921 (JP, A) JP-A-1-78240 (JP, U) JP-A-1-166713 (JP, U) JP-A 49- 77307 (JP, U) Japanese Utility Model 2-101035 (JP, U) Japanese Utility Model 4 44446 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01N 7/08 F02D 9 / 04

Claims (1)

(57) [Claims] In an internal combustion engine for a vehicle mounted on a motorcycle, an exhaust throttle valve whose opening degree can be adjusted is provided in an exhaust passage for exhausting exhaust gas from the internal combustion engine, and the exhaust throttle valve is used to rotate a stand of the motorcycle. An exhaust control device for an internal combustion engine for a vehicle, wherein an opening degree of an exhaust passage is reduced by an exhaust throttle valve when the stand is used, in conjunction with the movement.