JPS58177718A - Exhaust device of autobicycle - Google Patents

Abstract

PURPOSE:To prevent the decrease of strength of a strut further easily perform assembly and disassembly of an exhaust pipe, by forming the strut supporting a seat supporting frame to a plate shape crossing a car body. CONSTITUTION:A frame 1 is equipped with a main mast 3 extended diagonally rear downward from a steering shaft pipe 2 and a pair of left and right bottom located pipes 4 once extended downward thereafter curved to the rear. The first reinforcer frame 23 is connected between a curved part 49 of the pipe 4 and the mast 3, and the left and right pipes 4 are mutually connected and reinforced by the second reinforcer frame 24 immediately above curved parts 4a, then a powder unit 25 comprising an engine and a speed changer is mounted between these pipes. A strut 9 is formed to a box shape by doubly welding two sheets of aluminum alloy plate materials 9a, 9b and welded respectively to left and right seat supporting frames 7 in the upper part and to a bracket 5 in the bottom part. An exhaust pipe 28 is extended through a through hole 34 provided to both sides of the strut 9.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a motorcycle in which a power unit consisting of an engine, a transmission, etc. is arranged between the front and rear wheels, and is particularly applicable to modified motorcycles in which an exhaust pipe is connected to the rear of the engine. Regarding.

Generally, the body frame of a motorcycle has a reinforced structure in which the support frame that supports the passenger's seat and the main column that supports the rear part of the moving crab are connected by a column, and are formed in a substantially triangular shape.

By the way, when trying to connect the exhaust pipe extending rearward from the rear of the engine, the support strut gets in the way9.
The attachment/detachment work is significantly hindered.

The present invention is characterized in that, in order to solve the problem tS<9, the pillars are concentrated in the center of the vehicle body, and in order to prevent the accompanying decrease in rigidity, the pillars are formed into a box-like shape made of an upper plate material.

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

Reference numeral 1 designates the frame of a motorcycle], which includes a main pillar 3 extending rearward and diagonally downward from a steering shaft pipe 2, and a pair of descending pipes 4 on the left and right that extend downward and then rearward. and has. The main column 3 and the descending tube 4 have a cylindrical shape with a square cross section, and are made of pultruded aluminum alloy. ] are interconnected. The mouth is a reinforcing stay that supports the main pillar, 1 is a support frame for the passenger Gytro, and 9 is its support.

The front fork is rotatably supported by the 11Fi steering shaft tube 2, and 12 is a front wheel with a support stone at its lower end. Further, the front cover of the 13U vehicle body frame, 14 is a fuel tank.

A rear arm 16 is supported on the bracket 5 by a shaft 1s so as to be vertically swingable. 1T is the rear wheel. The rear arm 16 has a chevron-shaped reinforcing member 11 at the top! It- has integrally, the reinforcing member 18 has a rod 19 and a link 21
A shock absorber with a coil spring mounted on the left and right sides of the car body! 22.

The bent portion 4a of the descending pipe 4 and the main pillar 3 are connected by a first reinforcing frame 23, and the left and right descending pipes 4.4 are connected to each other by a second reinforcing frame 24 directly above the bent portion 4□. The dynamic crab unit 2 is reinforced and consists of an engine and a transmission between them.
It has a total of 5.

The moving crab knit 25 has an upper cylinder 26 and a lower cylinder 2.
V-type engine having 7. 28 and 29 are their exhaust pipes, and 31 is a carburetor.

As shown in FIG. 2, the first reinforcing frame 23 is constructed by welding an outer plate 231 and an inner plate 23b between the main column 3 and the descending pipe 4.
The two plates 23&, 23b are formed into a box shape by bending the edges of the front edges, abutting each other, and welding them at the W part. 32 is a cylindrical boss bridged and welded between the outer plate 23a and the inner plate 23b, with a rubber damper 33 interposed therebetween.
The power unit 2B is supported by bolts 34.

Therefore, by removing the bolt 34, the moving crab knit can be lowered to the lower part of the frame.

The second reinforcing frame 24 consists of a drawn aluminum alloy tube with a square cylindrical cross section, and as shown in FIG. 5, the center part is retracted to the rear. In this way, due to the cushioning effect of the front fork 11, when the front wheel 12 moves upward as indicated by imaginary -F, it does not come into contact with the second reinforcing frame 24. That is,
The descending pipe 4t is placed as far forward as possible, and the power 22) 25 is mounted in the front to increase the load acting on the front wheels, improving the running stability of competition motorcycles that tend to have less front wheel load. can be increased.

As shown in Fig. 3, the pillar 9 is made of aluminum alloy.
It is made into a box shape by polymerizing and welding two sheets of board material, and the upper part has left and right seat support frames TVC.

Also, the lower part is welded to the bracket 5. Reference numeral 34 indicates a through hole provided on both sides of the support column 90, through which the exhaust pipe 28 passes.

The seat 8 includes a main body 8a made of synthetic resin that constitutes the overall shape,
Seat plate 8b made of synthetic resin foam adhered to its top surface
It is placed and fixed on the seat support frame T via the cushion material 8c.

As described above, in this invention, the column supporting the passenger's seat support frame is formed into a plate shape that crosses the vehicle body, so it is possible to have a large section modulus, and the column is arranged at the center of the vehicle body. There is no decrease in the strength of the pillars. Also, the mud, muddy water, etc. thrown off by the rear wheels! Prevents the moving crab knit in front of the first part from getting dirty. Furthermore, since the strut is disposed at the center of the vehicle body, a through hole can be provided on the side thereof through which the exhaust pipe passes, and the exhaust pipe can be easily assembled and disassembled.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view showing the main parts of a motorcycle, Fig. 2 is a sectional view taken along
3 is a cross-sectional view taken along line Ill-H1, FIG. 4 is an external perspective view of the vehicle body frame, and FIG. 5 is a cross-sectional view taken along line V-V in FIG. 1. 111 Frame, T... Seat support frame, 8... Seat, 9... Work/support, 25... e... Moving crab knit, 28
Exhaust pipe for 1 day. Patent applicant Yamaha Motor Co., Ltd. II! Figure 2
311I (C1) Figure 4 Figure 5 Procedural amendment (method) ■, Minor case indication 1982 Patent Application No. 60176 2, Name of invention Motorcycle exhaust system 3, Person making the amendment Image type Patent Applicant name (name)
(Mu07) Yamahachi Engine Co., Ltd. 5, bli iE #
l<? Date: July 27, 1980 Ichimu - ■
Tsukuda←Te0) Engraving of drawings (no changes to the content)

Claims (1)

[Scope of Claims] The main pillar extends rearward from the steering shaft tube, branches midway and extends downward to support the rear part of the movable crab knit, and a seat support frame extends rearward substantially horizontally, and the main pillar In a motorcycle in which the lower end and the seat support frame are connected and reinforced by a strut, the strut is formed into a plate shape that crosses the vehicle body, and a ninth through hole is formed on the upper side of the strut to allow exhaust gas to pass through. Exhaust system provided.