JP3006271B2 - Motorcycle muffler and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler for a motorcycle and a method of manufacturing the muffler.

[0002]

2. Description of the Related Art A muffler of a motorcycle is disposed along a side of a vehicle body 1 as shown in a rear view of FIG. 10 so as to prevent heat damage to a rider's legs. Therefore, it is arranged below the pillion footrest. At this time, since it is necessary to secure a sufficient bank angle, the vehicle body 1 of the muffler 2 shown in FIGS.
A concave portion 3 is formed by recessing the side, so that the muffler 2 is disposed closer to the vehicle body 1 side, or a portion that may come into contact with the ground when the vehicle body 1 is banked as shown in FIGS. In addition, as shown in FIG. 16, a portion which has a possibility of grounding is removed, another plate material 4 is applied thereto, and the periphery thereof is integrated by welding 5 to form the concave portion 3 as shown in FIG.
It is dealt with by forming. In the above figure, 6
Denotes a rear wheel, 7 denotes an exhaust port, and 8 denotes an exhaust pipe.

[0003]

However, a part of the muffler 2 is crushed to form the recess 3 in FIGS.
In the case of (1), the circumferential length of the muffler 2 cannot be shortened, so that a rib-shaped groove 3a is formed. The groove 3a enters the inside of the muffler 2 and the capacity of the muffler 2 is greatly reduced. Since the cross-sectional shape of the muffler 2 is complicated, there is a problem that the joining property with the internal plate is deteriorated and the airtightness is impaired. In the case of FIG. 16 in which the recess 3 is formed by welding another plate material 4, the unnecessary length of the muffler 2 can be avoided, but the welding length increases because the outer periphery of another member is welded. However, there is a problem that the cost increases due to an increase in the number of parts and an increase in the welding length due to the preparation, and that the long welding length makes the appearance unsightly.

The present invention has been made in view of the above-mentioned circumstances, and provides a muffler for a two-wheeled vehicle which requires no reduction in the volume of the muffler, does not require extra parts, and has a short welding length, and a method of manufacturing the muffler. The purpose is to do.

[0005]

In order to solve the above-mentioned problems, a muffler for a two-wheeled vehicle according to the present invention has a cylindrical muffler having a cylindrical muffler which is inclined downward and rearward in the left-right direction of a vehicle body. A wheel, wherein the muffler is connected to the rear end of the exhaust pipe, and a concave portion is provided in a lower portion of the front end, and the concave portion is provided with a slit in the muffler component member to partially reduce the circumferential length, The slits are closed to form a flat bottom surface.

Further, the method for manufacturing a muffler for a motorcycle according to the present invention is a method for manufacturing a muffler for a two-wheeled vehicle, wherein a cylindrical muffler is mounted to be inclined downward and rearward below the left and right sides of the vehicle body. At the end of the muffler component, a slit is formed from the end of the muffler component to partially reduce the perimeter, and after closing the slit, the joint is welded to form a recess with a flat bottom surface at the lower front end of the muffler. Is formed.

[0007]

According to the muffler for a two-wheeled vehicle according to the present invention, a cylindrical muffler is attached to the lower side in the left and right direction of the vehicle body so as to be inclined upward and rearward, and a concave portion is provided at a lower portion of the front end thereof. A recess can be formed only in a portion that may sometimes be grounded. And, the concave portion is provided with a slit in the muffler constituent member to partially shorten the circumference,
By closing the slits and forming the bottom surface flat, no groove is formed on the bottom surface of the concave portion, and the volume of the muffler is not significantly reduced.

Further, according to the method for manufacturing a muffler for a motorcycle according to the present invention, a slit of a required length is formed from an end of the muffler constituting member to partially reduce the circumferential length, and this slit is formed. After the closing, the joint is welded to form a concave portion having a flat bottom surface at the lower front end of the muffler, so that it is not necessary to perform welding by applying another member, and the number of parts is not increased. Since the welding is performed only at the closing portion of the slit, the welding length is short, and the appearance is not unsightly unlike the case where another member is welded.

[0009]

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

FIG. 1 is an overall external view of a motorcycle provided with a muffler 10 according to the present invention.
Is attached to the rear of the vehicle body 12 via the mounting bracket 14 while being inclined upward and rearward below the lateral side of the vehicle body 12 below the seat 11. The muffler 10 is connected to a rear end of an exhaust pipe 15 connected to the exhaust side of the engine. Reference numeral 15a is an outlet.

The muffler 10 is typically constructed as a whole with a cylindrical structure as shown in FIGS.
5 is connected. To manufacture the muffler 10, FIG.
As shown in FIG. 6A, a V-shaped slit 17 is formed from one end of the muffler component 16 (blank) to partially shorten the perimeter, and this muffler component 16 is shown in FIG. 6B. After being rounded into a cylindrical shape, the slit 17 is closed as shown in FIG. Thereby, the slit 17
6 is flattened to the circular cross-section of the muffler 10, and the closed joint 18 of the slit 17 is shown in FIG.
As shown in (D), by integrating by the welding line 19, a concave portion 20 having a flat bottom surface is formed below the front end of the muffler 10.

The muffler 10 thus manufactured is
A concave portion 20 is provided in the lower portion of the front end, and the concave portion 20 is provided with a slit 16 in the muffler component member 16 to partially shorten the circumferential length, and the slit 16 is closed to form a flat bottom surface.

In this case, the position where the slit 17 is provided and its shape can be arbitrarily selected. For example, as shown in FIG. 7, a three-month slit 17a is formed in a portion of the concave portion 20 on the vehicle body 12 side, and this is closed and welded to form a muffler 10A as shown in FIGS. The welding line 19 is formed inside the recess 20, making it difficult to see the welding line 19 from the outside, so that a favorable appearance can be achieved.

Therefore, the slit 17 is formed from the end of the muffler component member 16, the slit 17 is closed, and the joint 18 is welded to form the concave portion 20 in a part of the muffler 10, 10A. 20 has a flat surface structure at the bottom, so that the volume of the mufflers 10, 10A is not significantly reduced. Further, since welding is performed only at the closed portions of the slits 17 and 17a, the welding length is short and the appearance is not unsightly.

[0015]

As described above, according to the muffler for a motorcycle according to the present invention, a cylindrical muffler is attached to the lower left and right sides of the vehicle body so as to be inclined upward and rearward, and a concave portion is formed at a lower portion of the front end thereof. With the provision, the concave portion can be formed only in a portion that may be grounded at the time of banking. The bank angle can be increased by forming the concave portion. The concave portion is provided with a slit in the muffler constituent member to partially shorten the perimeter, and the slit is closed to form a flat bottom surface, so that no groove is formed on the bottom surface of the concave portion, and the volume of the muffler is reduced. Can be significantly reduced.

According to the method for manufacturing a muffler for a motorcycle according to the present invention, a slit having a required length is formed from an end of the muffler component member to partially shorten the circumference, and this slit is formed. After closing, the joint is welded to form a recess with a flat bottom surface at the lower front end of the muffler, so there is no need to weld with another member, avoiding an increase in the number of parts and reducing costs. Can be achieved. Since welding is performed only at the closing portion of the slit, the welding length is short, the cost can be reduced, and the appearance is not unsightly unlike the case where another member is welded.

[Brief description of the drawings]

FIG. 1 is an overall external view of a motorcycle including a muffler according to the present invention.

FIG. 2 is a perspective view showing one embodiment of a muffler for a motorcycle according to the present invention.

FIG. 3 is a perspective view of the muffler of FIG. 2 viewed from another angle.

FIG. 4 is a view taken along the line IV-IV in FIG. 3;

FIG. 5 is a partially enlarged perspective view of FIG. 3;

6 (A) to 6 (D) are views showing a manufacturing procedure of the muffler shown in FIGS. 1 to 4.

FIG. 7 is a diagram showing a modified example of a muffler material constituting a muffler of a motorcycle according to the present invention.

FIG. 8 is a perspective view showing a modified example of the muffler.

FIG. 9 is an end view of the muffler shown in FIG. 8;

FIG. 10 is a front view illustrating a state of the two-wheeled vehicle to which the present invention is applied at the time of banking.

FIG. 11 is a plan view showing a conventional motorcycle muffler technique.

FIG. 12 is a front view showing a conventional motorcycle muffler technique.

FIG. 13 is a sectional view taken along line AA of FIG. 12;

FIG. 14 is a partial perspective view showing another example of the related art.

FIG. 15 is a sectional view taken along line BB of FIG. 14;

FIG. 16 is a partial perspective view showing still another example of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Muffler 11 Seat 12 Body 14 Mounting bracket 15 Exhaust pipe 16 Muffler constituent member 17 and 17a Slit 18 Joint 19 Welding line 20 Depression

Claims (2)

(57) [Claims] 1. A two-wheeled vehicle having a cylindrical muffler attached to a lower rear portion of a vehicle body in the left-right direction and having a cylindrical muffler attached thereto, wherein the muffler is connected to a rear end of an exhaust pipe.
A concave portion is provided at the lower front end, and the concave portion is provided with a slit in the muffler constituent member to partially reduce the circumferential length,
A muffler for a motorcycle, wherein the slits are closed to form a flat bottom surface. 2. A method for manufacturing a muffler for a two-wheeled vehicle for manufacturing a cylindrical muffler which is attached to a lower side portion of a vehicle body in a left-right direction and inclined upward and rearward, wherein a slit is formed from an end of a muffler component member. The muffler of a two-wheeled vehicle is characterized in that the perimeter is partially shortened, the slit is closed, and the joint is welded to form a concave portion having a flat bottom surface at the lower front end of the muffler. Production method.