JP3269898B2 - Exhaust valve device for motorcycle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction in which fresh air in a combustion chamber is burned by self-compression ignition during low load operation.
The present invention relates to a motorcycle exhaust valve device applied to a cycle engine.

[0002]

2. Description of the Related Art Conventionally, it is known to mount an exhaust valve device to a muffler component of a two-cycle engine motorcycle in order to burn fresh air in a combustion chamber by self-compression ignition during low load operation.

[0003]

In the prior art, the arrangement of the exhaust valve device was not sufficiently considered, and the existence of the exhaust valve device had a problem in relation to other parts.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to secure a bank angle without obstructing the operation of a motorcycle. It is an object of the present invention to provide a motorcycle exhaust valve device capable of performing the above.

[0005]

According to a first aspect of the present invention, there is provided an exhaust valve device comprising an exhaust valve for opening and closing an exhaust passage and a shaft serving as a rotating shaft of the valve in the middle of an exhaust pipe. When the vehicle is viewed from the front, the shaft is inclined so that the center of the vehicle body is lower and the side of the vehicle is higher when the vehicle is viewed from the front. Position it closer to the center of the vehicle than the line that contacts the end of the step to be mounted and the side of the front wheel, and connect it to the throttle cable.
The drum to be connected on the side opposite to the step across the exhaust pipe.
It is characterized by being attached to the shaft while being placed .

[0006]

According to the first aspect, the exhaust valve device does not hit the ground even when the step hits the ground when the vehicle body is tilted, so that the bank angle determined by the line can be prevented from being reduced. Also, the drum should be farther away from the line
And the bank angle can be secured. Furthermore, Dora
The pump on the opposite side of the exhaust pipe from the step.
Can prevent, for example, drum mischief
And the drum hits the ground when the vehicle leans.
And the bank angle can be increased.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a schematic side view of a motorcycle to which the exhaust valve device for a motorcycle according to the present invention is applied, and FIG.
FIG. 2 is an enlarged view of an essential part in a cross section taken along line AA of FIG. 1.

As shown in FIG. 1, in a motorcycle,
A front wheel 2 is supported by a front fork 3 at a lower portion on the front side of the vehicle body 1, and the front fork 3 is rotatably supported at an upper portion thereof by a head pipe 4 of the vehicle body 1.

[0009] At the upper end of the front fork 3, left and right handle grips 6, 6 are disposed on both ends of a bar-shaped handle 5 on a top bridge, and a front face of the handle 5 faces forward. A lamp 7 and direction indicator lamps located on both left and right sides thereof are provided. The upper part of the front wheel 2 is covered with a fender 8.

On the other hand, a vehicle body frame 9 is formed from the front side to the rear side of the vehicle body 1, and a power unit 10 is provided substantially below the center of the vehicle body frame 9.
Muffler component 11 that silences and exhausts exhaust gas
Is mounted on the right side of the vehicle body 1 so as to be parallel to the vehicle body 1. The muffler component 11 is an upstream exhaust pipe 11
a, a downstream exhaust pipe 11b and a muffler 11c.

Further, as shown in FIG.
A step 12 for placing a foot is provided at the lower end of the arm, and a swing arm 14 supporting a rear wheel 13 is rotatably supported. The body frame 9 is covered with a power unit cover 15, a body cover 16 extending to the upper rear of the rear wheel 13, and the like, and a seat 17 is provided above the body cover 16. 18 is Anda Cowl.

The exhaust valve 20 includes a muffler component 11
Upstream exhaust pipe 11a and downstream exhaust pipe 11
b.

As shown in FIG. 2, the exhaust valve 20 includes a pipe 21, a shaft 22 having both ends protruding from the pipe 21 at right angles to the axial direction of the pipe 21, and a valve 23 fixed to the shaft 22 in the pipe 21. , A drum 24 fitted to a shaft 22 protruding from the pipe 21.
A throttle cable 25 for driving the exhaust valve 20 in conjunction with the movement of the handle grip 6 is connected to the drum 24.
Is wound. The exhaust valve 20 is covered with a protector 20a to protect its components.

Then, as shown in FIG.
Since 0 is provided inside the under cowl 18,
It is possible to prevent stones, muddy water, curbs and the like from directly hitting the exhaust valve 20 during traveling. Further, as shown in FIG. 2, the installation angle θ1 of the exhaust valve 20 is 0 to 45 degrees with respect to the ground line GL. Therefore,
Since it is inside the plane formed by the line S connecting the side of the front wheel 2 and the end of the step 12, the bank angle θ2 can be secured. In addition, C is a vehicle center line as the vehicle center.

Further, as shown in FIG.
Is installed in front of the lowermost portion 11d of the muffler component member 11, so that it is possible to prevent a valve operation failure due to oil beforehand.

[0016]

As described above, according to the present invention, in the motorcycle exhaust valve device of the first aspect, when the vehicle body is viewed from the front, the shaft is lower at the vehicle body center side and higher at the vehicle body side. The exhaust valve device including the shaft is arranged so as to be inclined toward the center of the vehicle body with respect to a line contacting the end of the step to be put on the driver's foot and the side of the front wheel, and is connected to the throttle cable. ,
On the shaft while placing it on the opposite side of the step from the trachea
Because the installed exhaust valve device also hit the step the ground when the vehicle body is tilted not hit the ground, it is possible to prevent the bank angle determined by the line is small, it is possible to ensure a bank angle, In addition, the drum must be
By placing on the opposite side of the step across the
For example, you can prevent mischief with the drum,
When the body leans, the drum will not hit the ground easily,
The bank angle can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a motorcycle to which a motorcycle exhaust valve device according to the present invention is applied.

FIG. 2 is an enlarged view of an essential part of a cross section taken along line AA of FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Front wheel, 11 ... Muffler component member, 11
a , 11b ... exhaust pipe (upstream exhaust pipe, downstream exhaust pipe
Flop), 11c ... muffler, the bottom of the 11d ... muffler component, 12 ... step, 18 ... under cowl, 20 ...
Exhaust valve device (exhaust valve) , 22 ... shaft, 23
... Valve, 24 ... Drum, 25 ... Throttle cable,
C: Vehicle center (body center line), GL: Ground line,
S: line, θ1: installation angle, θ2: bank angle.

────────────────────────────────────────────────── (5) References JP-A-62-206222 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02B 27/06 F02D 9/04

Claims (1)

(57) [Claims] 1. A motorcycle in which an exhaust valve device including a valve for opening and closing an exhaust passage and a shaft serving as a rotation shaft of the valve is interposed in the middle of an exhaust pipe. Is tilted so that the center of the vehicle body is lower and the side of the vehicle body is higher, and the entire exhaust valve device including this shaft is moved from the line tangent to the end of the step for placing the driver on the foot and the side of the front wheel. Arrange near the center and connect to the throttle cable
Move the drum to the opposite side of the step with the exhaust pipe
An exhaust valve device for a motorcycle, wherein the exhaust valve device is mounted on the shaft while being arranged .