JP2005090237A - Connecting structure and cover of muffler of motorcycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting structure of a muffler of a motorcycle, to be made beautifully visible in an appearance, by further simplifying a connecting part of the mufflers and a cover of its upstream side exhaust pipes. <P>SOLUTION: This connecting structure connects the mufflers 4A and 4B arranged in the tail end part of exhaust passages 5A and 5B of the motorcycle 50, allowing exhaust gas to exist inside, and exhausting the exhaust gas outward from the tail end, and the cover 8 for covering the exhaust pipes arranged on its upstream side. The exhaust pipes 3A and 3B are connected so that the exhaust gas flows to the mufflers. The mufflers and the cover 8 for covering the outer peripheral side of the exhaust pipes except for a fastening part of at least an installing part of the exhaust pipes, are connected in a nesting shape. The cover 8 is fastened and joined to the mufflers by a ring-shaped band member 9 for revolving around the outer periphery of the mufflers. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a muffler connection structure for a motorcycle, and more particularly to a connection structure between a muffler and a cover, and the cover.

In the case of motorcycles as well as other products, diversification has progressed, and various types of motorcycles are offered to the market.
In recent years, the displacement of a large motorcycle tends to increase gradually. As one type of such a large motorcycle, there is a so-called "American" type used mainly in the United States. This "American" type motorcycle basically has a capacity of each cylinder. A large V-type 2-cylinder engine is used, and a low-speed engine is mounted as a prime mover.

  The rider enjoys the low frequency vibrations and exhaust sounds generated by the engine over the large and low seat position of the "American" type motorcycle.

In many motorcycles including such “American” type, the muffler is constituted by a pipe whose outer peripheral surface is plated or a stainless steel pipe, and the exhaust pipe on the upstream side thereof is plated on the outer peripheral side. By covering with a cover, a process for making the appearance beautiful is performed so as to create a sense of unity with the muffler (see Patent Document 1).
JP2003-227333A.

  The present invention has been made in view of the present situation, and is a motorcycle muffler that makes it easier and more beautiful to show the connection between the muffler and the exhaust pipe cover on the upstream side. The object is to provide a connection structure and a cover.

The motorcycle muffler connection structure according to the present invention is provided at the end of the exhaust passage of the motorcycle, and covers the muffler that exhausts exhaust gas from the end and the exhaust pipe disposed upstream thereof. A connection structure with the cover,
The exhaust pipe is connected to the muffler so that the exhaust gas flows,
Connecting the muffler and a cover that covers the outer periphery of the exhaust pipe excluding at least a tightening portion of the exhaust pipe; and
The cover is joined to the muffler by fastening with a band member that goes around the outer periphery of the muffler.

The cover of the motorcycle according to the present invention is provided at the end portion of the exhaust passage of the motorcycle, and is arranged on the muffler that exhaust gas exists inside and exhausts the exhaust gas from the end to the outside or on the upstream side thereof. A cover covering the exhaust pipe,
The cover is integrated with an inner plate disposed on an inner periphery thereof and having an inner surface spaced apart from the outer surface of the muffler or the exhaust pipe via a honeycomb-shaped connecting member.

  According to the motorcycle muffler connection structure according to the present invention configured as described above, exhaust gas can be discharged into the muffler from the exhaust pipe, and in appearance, the muffler and its upstream exhaust pipe However, the cover that covers the outer periphery of the exhaust pipe and the muffler are connected by a band member, so that they can be formed as if they were integrated in a state where there is no connection portion.

  Moreover, according to the motorcycle cover according to the present invention configured as described above, the appearance is beautiful, the heat transfer rate from the exhaust pipe or the muffler side to the cover 8 side is reduced, and the rigidity is further improved. The chatter noise can also be reduced by increasing.

  Further, in the connection structure of the muffler of the motorcycle, if the tightening portion is located on the vehicle body side of the muffler so as not to be seen from the side of the motorcycle, it is a preferable configuration in appearance.

Further, in the connection structure of the muffler of the motorcycle, the ring-shaped band member is composed of at least two members, and connecting means for connecting the two members to each other is formed.
When one member of the at least two members is integrally fixed to the inner peripheral surface of the cover, the muffler cover can be easily attached to the muffler side at the connection portion.

  Moreover, in the connection structure of the muffler of the motorcycle, the connection means is either one member that is integrally fixed to the inner peripheral surface of the cover and the other member that is connected to the member. In addition, the holding means for slidably holding the other member makes it easier to attach even in places where the operator cannot visually recognize.

  Further, in the connection structure of the muffler of the motorcycle, the holding means can be configured to be holding claws that hold both sides of the one member and the back thereof.

  Further, in the motorcycle muffler connection structure, a stopper mechanism for defining the slidable end is provided on the one member and the other member held by the one member by the holding means. And one member and the other member do not come off at the time of sliding, and the construction is excellent in workability.

  Further, in the motorcycle muffler connection structure, when the connecting means is a connecting mechanism that is connected by a bolt and a nut, firm fastening is possible.

  Further, in the muffler connection structure of the motorcycle, the connecting means is constituted by a locking hole formed in one member of the at least two members and a hook portion locked in the locking hole. In such a configuration, the configuration is simple and has excellent manufacturability.

  Hereinafter, a muffler of a motorcycle according to an embodiment of the present invention will be specifically described with reference to the drawings.

  FIG. 1 is an overall side view of a motorcycle according to one embodiment of the present invention, and FIG. 2 is an exhaust pipe on the upstream side in the exhaust muffler and its exhaust gas flow shown in FIG. FIG. 3 is a cross-sectional view taken along the long axis direction of the cut surface showing the internal structure of the muffler shown in FIGS. 1 and 2. FIG. 4 is a plan view of the muffler shown in FIG. 3 as viewed from directly above, and FIG. 5 is the major axis direction of the oval cut surface showing the configuration of the rear end portion of the muffler (in the direction of arrows VV in FIG. 3). It is the fragmentary sectional view which followed the cross section.

The so-called “American type” motorcycle 50 shown in FIG. 1 is equipped with a so-called “V twin type” engine 1 in which two cylinders 2A and 2B are arranged in a V shape in a side view. In this engine 1, an exhaust pipe 3A from one cylinder 2A arranged in a V shape and an exhaust pipe 3B from the other cylinder 2B extend toward the rear of the motorcycle 50, respectively. The rear ends of 3A and 3B are connected to separate mufflers 4A and 4B, respectively. As shown in FIG. 1, in the vicinity of the front end of the rear wheel 51, the muffler 4A connected to the exhaust pipe 3A and the muffler 4B connected to the exhaust pipe 3B are parallel to each other in the vertical direction. In the state, it extends backward.
The exhaust pipe 3A and the muffler 4A form a first exhaust passage 5A for the cylinder 2A, and the exhaust pipe 3B and the muffler 4B form a second exhaust passage 5B for the cylinder 2B. Is formed. As shown in FIG. 2, the first exhaust passage 5A and the second exhaust passage 5B are arranged in the middle positions of the exhaust pipe 3A and the exhaust pipe 3B, and the muffler 4A and the muffler 4B. They are connected to each other by connecting pipes 10 and 11 at the position of the upstream end.

By the way, in the case of the mufflers 4A and 4B of the motorcycle according to this embodiment, as shown in FIG. 3, each has the form of a double tube comprising an inner tube 4b and an outer tube 4c, and the inner tube 4b. The exhaust gas from the exhaust pipe 3 </ b> A (or 3 </ b> B) passes through the inside. In addition, a silencer mechanism 4R such as a baffle plate for enhancing the silencing effect is incorporated in the inner tube 4b.
As shown in FIG. 3, the outer tube 4c extends further rearward than the rear end of the inner tube 4b. The end of the extended outer tube 4c is as shown in FIG. In a state where the cut surface 4a is inclined substantially outward with respect to the longitudinal direction of the outer tube 4c so that the cut surface 4a is inclined outward and approximately 20 degrees downward, the motorcycle It is cut so that it faces 50 (outside).

  As shown in FIG. 5, the outer tube 4 c has a bent portion 4 e that is bent inwardly at the rear end thereof in a round shape, and an end 4 k that extends from the bent portion 4 e to the front side of the motorcycle 50. As shown in FIG. 3, it extends toward the inner tube 4b side to a position further forward than a terminal end 6e of the discharge pipe 6 described later. In this embodiment, the end 6c is not connected to the inner tube 4b side and is a free end.

In the case of this embodiment, as shown in an enlarged view in FIG. 5, the radius of curvature of the bent portion 4e is formed to be about 2 mm to 3 mm, and the exhaust gas (exhaust flow) discharged from the inside to the outside is smooth. It is configured to be discharged outward from the peripheral edge of the cut surface 4a.
The discharge pipe 6 passes through a lid member 4f (see FIG. 3) provided at the end of the inner tube 4b and protrudes backward.
In this embodiment, the rear end 6e of the discharge pipe 6 is located slightly rearward from the position of the end 4k inverted to the front of the outer tube 4c, and is the frontmost position of the cut surface 4a. 4j is located slightly forward (in this embodiment, about 3 to 7 cm forward), and therefore the portion of the discharge pipe 6 protruding from the inner tube 4b is surrounded by the outer tube 4c. Therefore, the exhaust gas (exhaust sound) is discharged into the space surrounded by the outer tube 4c.
In the case of this embodiment, as shown in FIG. 5, the outer tube 4c has two members 4w and 4q joined together at the bent portion 4e of the outer tube 4c for manufacturing reasons. However, the bent portion 4e may be formed by deep drawing a single plate.

  As is apparent from FIG. 2, the outer periphery of the exhaust pipes 3A and 3B except for the vehicle body side is covered with a cover 8, and the rear end 8e of the cover 8 is the front end 4s of the mufflers 4A and 4B. By connecting with the following connection structure, as shown in FIG. 1, the exhaust pipe 3A (3B) and the muffler 4A (4B) on the rear end side are formed by a single exhaust pipe. It is formed in the appearance that is not formed.

  As shown in FIG. 2, the respective covers 8 for the mufflers 4 </ b> A and 4 </ b> B are connected by a band member 9. That is, a main portion 9A (see FIG. 6) constituting a part of the ring-shaped band member 9 is integrally attached to the inner surface of the rear end of the cover 8 (spot welding in this embodiment). The auxiliary portion 9B (see FIG. 7) is connected to the portion 9A, and is configured to have a ring shape as a whole. More specifically, one of the two connections is connected by the “engaging mechanism” by the hook portion 9b shown in FIG. 6 (a) to the hole portion 9a shown in FIG. 7 (b). In addition, other parts are connected by passing a bolt (not shown) through a hole 9d shown in FIG. 6 (b) and fastening the male screw portion of the tip to a female screw portion 9f of a nut 9n shown in FIG. 7 (a). The “screwing mechanism” is used. That is, the band member 9 is composed of two members, a main portion 9A and an auxiliary portion 9B, and the engaging mechanism (the hole portion) is connected to each end portion of the main portion 9A and the auxiliary portion 9B as a connecting portion. 9a and the hook portion 9b) and a screwing mechanism (the nut 9n and a bolt (not shown) screwed to the nut 9n).

However, instead of the engagement mechanism (the hole portion 9a and the hook portion 9b), as shown in FIG. 9, both sides of the main portion 9A integrally attached (spot welded) to the cover 8 side. In addition, a pair of left and right holding claws 9r that hold the auxiliary portion 9B in a slidable manner are formed, and the auxiliary portion 9B is slidable with respect to the main portion 9A (see the sliding direction R in FIG. 9). It can also be configured by a holding means that holds it. Further, in this embodiment, in addition to the holding claw 9r, a projection 9y protruding toward the auxiliary portion 9B is provided on the main portion 9A side (in this embodiment, the front end of the main portion 9A), and the auxiliary nail is provided. By extending a groove 9u having a groove width substantially equal to the width of the protrusion 9y on the side of the portion 9B along the sliding direction so that this portion can also be slidably held, the sliding operation becomes smoother. In addition, it is possible to realize a slide mechanism having a configuration that hardly swings in the width direction. Further, the projection 9y and the groove 9u also function as a stopper mechanism that limits the end and start of the slide of the main portion 9A and the auxiliary portion 9B, so to speak, it has a configuration of “two birds with one stone”.
As described above, when configured to be slidable, the auxiliary mechanism 9B is simply slid with respect to the main part 9A even in a place where it cannot be visually recognized, so that the screwing mechanism (illustrated with the nut 9n is screwed to this). The screw can be easily and quickly screwed. In addition, as described above, when the stopper mechanism is provided, the auxiliary portion 9B does not drop out of the main portion 9A, and the workability is excellent.
Therefore, as in this embodiment, it is possible to realize a configuration that can be easily attached even when the nut 9n and a bolt (not shown) that is screwed to the nut 9n are screwed in a place that is not visible to the operator. . 9, the same components as those in FIGS. 6 and 7 are denoted by the same reference numerals, and the description thereof is omitted.

  By the way, in the said Example, although the holding mechanism by the holding claw 9r and the holding mechanism by the protrusion 9y and the groove | channel 9u are provided, it can also be set as the structure of only one holding mechanism.

The actual connection (connection) of the cover 8 to the muffler 4A (4B) is a state in which the main portion 9A fixed to the cover 8 is in contact with the outer periphery of the front end of the outer tube 4c of the muffler 4A (4B). That is, when viewed from the side, in a state where the cover 8 is joined to the muffler 4A (4b) in a so-called “nesting manner”, the hook portion 9b of the main portion 9A is engaged with the hole 9a of the auxiliary portion 9B. The bolt 9d is fastened by screwing the end of a bolt (not shown) from the hole 9d of the main portion 9A toward the nut 9n of the auxiliary portion 9B, and as a result, a reliable connection is made. Yes.
As shown in FIG. 2, the fastening portion by the bolt (not shown) and the nut 9n (see FIG. 7 (a), FIG. 9) is on the vehicle body frame side (the side of the muffler 4A (4B) from the vehicle body). 1, the position is hidden from the side of the motorcycle 50 as shown in FIG. 1, and the connection portion can be made inconspicuous in appearance.
The bolt (not shown) and the nut 9n can be easily fastened from above or below the mufflers 4A and 4B by a box wrench or the like.

  Further, as shown in FIG. 2, the exhaust pipe 3A (3B) and the muffler 4A (4B) are connected to the introduction pipe portion 14 protruding forward from the upstream end of the muffler 4A (4B). ) Are connected via connecting members 17, 18, and this connecting portion is fastened by a ring-shaped band metal fitting 19, whereby exhaust gas is discharged from the exhaust pipe 3 A (3 B) to the muffler 4 A (4 B). It is configured to be. In this embodiment, the band metal piece 19 is different from the band member 9 in this embodiment, and is integrally formed in a ring shape and detachable by one connecting portion.

  Further, in this embodiment, the cover 8 also has two cross-sections in FIG. 8 so as not to generate a chatter noise by increasing the rigidity, and so that mutual vibrations interfere with each other. As shown in the drawing, an inner plate 8N is disposed in a state where the inner surface of the cover 8 is separated from the outer peripheral surface of the exhaust pipe 3A (3B) in a cross-sectional view (a state where a gap is provided). The inner plate 8N is integrally joined with a honeycomb-shaped connecting member 8W. Of course, with this configuration, the heat transfer rate from the exhaust pipe 3A (3B) side to the cover 8 side can also be reduced. The cover 8 and the connecting member 8W are integrated by so-called “spot” welding, and the inner plate 8N and the connecting member 8W are integrated by so-called “plug welding”. You may arrange | position the cover provided with such a structure also to the outer periphery side of a muffler.

  According to the mufflers 4A and 4B according to the present embodiment having the above-described configuration, the mufflers 4A and 4B have a double pipe shape, and pass through the discharge pipe 6 from the inner tube 4b. The exhaust gas discharged to the outside air side has a rear end of the outer tube 4c extending rearward from the discharge pipe 6, and a bent portion 4e at the rear end of the outer tube 4c is bent in a round shape. Therefore, the rigidity of the rear end of the outer tube 4c itself is increased, and the expansion loss of the exhaust sound exhausted to the outside air is reduced, so-called “repelling sound” and “chatter noise” that become noises are generated. Occurrence is effectively prevented, and only a deep and pure exhaust sound is emitted from the cut surface 4a at the rear end of the mufflers 4A and 4B to the outside air side. Moreover, since the cut surface 4a is directed downward by about 20 degrees, the cut surface is cut obliquely with respect to the longitudinal direction so that the cut surface faces substantially outward of the motorcycle 50. Riders and passengers as well as those on the side will hear a moderate (comfortable) exhaust sound.

  Further, the mufflers 4A and 4B can be easily connected to the cover 8 covering the exhaust pipes 3A and 3B located on the upstream side at the front ends (upstream ends) with good appearance from the side.

  Further, in this embodiment, the cut surface 4a at the rear end of the outer tube 4c of the mufflers 4A and 4B is inclined so as to be directed downward by about 20 degrees. As a result of the inclination of about 20 degrees to the side stand side, the cut surface 4a located on the opposite side of the side stand can be seen sideways, and a favorable appearance is created.

  However, as described above, the angle tilted downward may be about 15 degrees smaller than 20 degrees, or may be about 30 degrees larger than 20 degrees. That is, this angle is preferably an inclination angle suitable for the inclination of the motorcycle when parked by the side stand, for example, a range of about 15 degrees to 30 degrees, and may be a range of about 10 degrees to 40 degrees.

  The motorcycle muffler connection structure and cover according to the present invention can be applied to various motorcycles or motorcycles.

1 is an overall side view of a motorcycle according to one embodiment of the present invention. FIG. 2 is an enlarged perspective view of a main part viewed from an upper position on the center side of the vehicle body showing a muffler of the motorcycle shown in FIG. 1 and an exhaust pipe on the upstream side of the muffler and a cover that covers an outer portion of the exhaust pipe. FIG. 3 is a cross-sectional view taken along the longitudinal direction showing the internal structure of the muffler shown in FIGS. 1 and 2. It is the top view which looked at the muffler shown in FIG. 3 from right above. It is the fragmentary sectional view which cut along the major axis direction (VV arrow direction of FIG. 3) of the elliptical cut surface which shows the structure of the rear-end part of a muffler. It is a figure which shows the structure of the principal part of the band member for attaching the cover which covers an exhaust pipe to a muffler, (a) is a rear view seen from the connection end side of a cover, (b) is VIb-of (a) VIb is an arrow view. It is a figure which shows the structure of the auxiliary | assistant part of the band member for attaching the cover which covers an exhaust pipe to a muffler, (a) is a rear view seen from the connection end side of a cover, (b) is VIIb-of (a) VIIb arrow view, (c) is the VIIc-VIIc arrow view of (a). FIG. 2 is a cross-sectional view taken along arrows IIXa-IIXa and IIXb-IIXb in FIG. It is a perspective view of the connection part of a muffler and a cover which shows the structure of the connection means concerning another embodiment with the connection means shown in FIG. 6, FIG.

Explanation of symbols

3A, 3B Exhaust pipes 4A, 4B Mufflers 5A, 5B Exhaust passage 8 Cover 9 Band member 50 Motorcycle

Claims (9)

A connection structure of a muffler that is provided at a terminal portion of an exhaust passage of a motorcycle and discharges exhaust gas outward from the terminal end, and a cover that covers an exhaust pipe disposed upstream thereof,
The exhaust pipe is connected to the muffler so that the exhaust gas flows,
Connecting the muffler and a cover that covers the outer periphery of the exhaust pipe excluding at least a tightening portion of the exhaust pipe; and
A muffler connection structure for a motorcycle, wherein the cover is joined to the muffler with a band member that circulates around the outer periphery of the muffler.   The muffler connection structure according to claim 1, wherein the tightening portion is located on a vehicle body side of the muffler and cannot be seen from a side of the motorcycle. The ring-shaped band member is composed of at least two members, and connecting means for connecting the two members to each other is formed.
The muffler connection structure according to claim 1, wherein one of the at least two members is integrally fixed to an inner peripheral surface of the cover.   The connecting means slidably holds the other member on one member of the one member integrally fixed to the inner peripheral surface of the cover and the other member connected thereto. 4. The muffler connection structure according to claim 3, wherein the muffler connection structure is a holding means.   The muffler connection structure according to claim 4, wherein the holding means is a holding claw that holds both sides of the one member and a back surface thereof.   The muffler according to claim 4, wherein a stopper mechanism for defining the slidable end is provided on the one member and the other member held by the one member by the holding means. Connection structure.   The muffler connection structure according to claim 3, wherein the connection means is a connection mechanism connected by a bolt and a nut.   The said connection means is comprised by the latching hole formed in one member of the said at least two members, and the hook part latched by this latching hole. Muffler connection structure. A cover that is provided at the end of the exhaust passage of the motorcycle, covers a muffler that exhausts exhaust gas from the end and exhausts the exhaust gas outward from the end, or an exhaust pipe disposed upstream thereof,
The motorcycle, wherein the cover is integrated with an inner plate disposed on an inner periphery thereof and having an inner surface spaced apart from the outer surface of the muffler or the exhaust pipe via a honeycomb-shaped connecting member. Cover.

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