JPH0310977A - Body frame of motorcycle - Google Patents

Abstract

PURPOSE:To increase the rigidity of a frame member and improve maintain- ability by so forming the frame member as to be approximately triangular when viewed from the rear side and long when viewed from the side in the constitution wherein the frame member fitted to the rear end of the main frame supports the upper end of a rear wheel bumper. CONSTITUTION:A main frame 1 comprising a pair of right and left portions with the front end part thereof connected to a head pipe 5 and extended aslant down, has a stay part 20 bent down like a hook and connected to the rear end thereof. In addition, the front end of a rear arm 7 for supporting a rear wheel 4 is pivotally supported on the rear arm pivot 6 where the stay part 20 is provided. Also, a frame member 8 is connected between the rear ends of the main frames 1 and 1, and a bumper 9 is connected between the width-wise center of the frame member 8, and a link 11 for connecting the aforesaid stay pat 20 and the rear arm 7. In this case, the frame member 8 is so formed as to be approximately rectangular when viewed from the rear side, and long-size and extended aslant back from the rear end of the main frame 1 when viewed from the side.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a motorcycle body frame in which only one rear wheel shock absorber is provided at the center of the vehicle width.

[Prior art]

Some rear wheel shock absorbers for motorcycles have only one shock absorber installed in the center of the vehicle width. Japanese Patent Publication No. 1986-19747
As disclosed in Japanese Patent No. 7, this one shock absorber is provided between the rear arm and a frame member that connects the rear end portions of the pair of left and right main frames. In such a configuration, the frame member needs to have sufficient rigidity to support the reaction force from the rear wheel, so its shape is wide in the front and rear direction,
Moreover, it extends in substantially the same direction as the longitudinal direction of the shock absorber.

However, if the frame members are wide in the front and rear, and are also provided along the longitudinal direction of the shock absorber, it is not only difficult to check the shock absorber from the side of the car body, but also difficult to reach. Have difficulty. As a result, the actual situation was that the maintainability of the buffer was extremely poor.

[Problems to be Solved by the Invention] An object of the present invention is to install the above-mentioned rear wheel shock absorber in the center of the vehicle width.
To provide a vehicle body frame that improves the maintainability of a shock absorber while ensuring the rigidity of a frame member supporting the shock absorber in a motorcycle in which only books are arranged.

[Means to solve the problem]

To achieve the above object, the present invention has a pair of left and right main frames extending obliquely downward from the head pipe to above the rear arm pivot, and the rear ends of the left and right main frames are connected to each other. A motorcycle in which a frame member is provided, and one shock absorber extending in the vertical direction is arranged between the frame member and the rear arm, the frame member comprising:
When viewed from the rear, it has a substantially triangular shape consisting of a base that connects the left and right rear end portions of the left and right main frames in a substantially straight line, and both sides that extend obliquely inward and upward from both rear end portions, and when viewed from the side, the rear end of the main frame has a substantially triangular shape. Extending diagonally backward and upward from the end,
The shock absorber is characterized in that it has an elongated shape that intersects with the longitudinal direction of the shock absorber.

〔Example〕

In the embodiment shown in FIGS. 1 to 5, 1 is a main frame, 2 is an engine, 3 is a front wheel, and 4 is a rear wheel.

The main frame 1 is formed by welding an outer panel 1o and an inner panel 11, and is hollow so that the cross section is substantially rectangular, and has a wide band shape when viewed from the side. A pair of left and right main frames 1 are provided, each having a front end connected to the head vibrator 5 and extending diagonally downward.

A cast stem part 20 bent downward into a hook shape is connected to the rear end.

The main frame 1 has a suspension part 31 extending downward in the middle part, and the head of the engine 2 is attached to this suspension part 31 by bolts 32.
At the same time, the rear part of the engine is fixed to the rear end of the main frame 1 and the stem part 20 by bolts 33 and 34, respectively. The suspension portion 31 is formed so that the outer panel 1o of the main frame 1 extends seamlessly as it is, and an inner panel 35 made of cast or cut material is welded to the back side of the outer panel 1o. By configuring the three suspension parts seamlessly by the extension of the outer panel 10 in this way, it is possible to ensure strength without increasing the thickness of the wall to prevent stress concentration on this part.

Further, a fuel tank 36 is mounted on the upper surface of the main frame 1 via a rubber cushion 37, and is fixed to the main frame 1 at the front and to the frame member 8 at the rear with bolts 38, respectively. The stem part 20 has a rear arm pivot 6, and a rear arm 7 is pivotally supported on the arm pivot 6. Further, the rear wheel 4 is supported at the rear end of the rear arm 7.

A frame member 8 is connected between the rear end portions of the pair of left and right main frames 1.1. On the other hand, a link 10.11 is connected between the lower end of the stem part 20 and the middle part of the rear arm 7, and a shock absorber 9 is connected between the link 11 and the widthwise center part of the frame member 8. are connected.

The frame member 8 is formed by welding members 8a, 8a each having a right triangular cross section in the width direction, and cross members 8b, 8c connecting the upper and lower parts thereof, respectively, to each other.

Further, the frame member 8 formed in this manner is hollow inside and is used as an oil tank 21. This oil tank 21 forms a lower chamber 21a and an upper chamber 21b that communicate with each other. 2
2 is an oil inlet of this oil tank 21, and 23 is an oil outlet.

The overall shape of the frame member 8 is approximately triangular in rear view, consisting of a base connecting the rear ends of the left and right main frames in a substantially straight line, and both sides extending diagonally inward and upward from both rear ends. None, and the shape in side view is an elongated shape extending diagonally rearward and upward from the rear end of the main frame.

In this way, by making the frame member 8 substantially triangular in rear view, sufficient rigidity can be maintained against the reaction force from the rear wheel 4.

In addition, since the frame member 8 intersects with the longitudinal direction of the shock absorber 9 when viewed from the side, the shock absorber 9 can be easily seen from the side of the vehicle body, and necessary maintenance work can be carried out by inserting a hand into the shock absorber 9. can do.

Further, a box 13 for storing a battery 12 is attached to the frame member 8. Further, a stay 14 is fixed to the box 13, and a silencer 15 is suspended by the stay 14. In addition, the frame member 8
A front end portion of a seat cowl 16 is fixed to the seat cowl 16 with bolts 17.

Figure 6.7 shows another embodiment of the invention.

In this embodiment, the lower end of the shock absorber 9 is directly pivoted to the rear arm 7, and is connected to the rear arm 7 without using a link as in the first embodiment. In addition, the internal space of the frame member 8 is not separated into upper and lower parts as in the first embodiment;
The entire oil tank 21 has one space. Further, in this embodiment, the seat cowl 16 is connected to the fuel tank 3.
6 by bolts 39.

However, the overall shape of the frame member 8 is the same as that of the first embodiment, and the shape in rear view is the same as the bottom that connects the rear ends of the left and right main frames in a substantially straight line, and Each has a substantially triangular shape with both sides extending diagonally inward and upward, and the shape in side view is an elongated shape extending diagonally rearward and upward from the rear end of the main frame. The configuration is different from that of the first embodiment. Therefore, this frame member 8 also maintains sufficient rigidity against the reaction force from the rear wheels 4, and also allows the shock absorber 9 to be easily seen from the side of the vehicle body, and can be handled easily while attached to the vehicle body frame. can be installed to perform necessary maintenance work.

〔Effect of the invention〕

As described above, the body frame of a motorcycle according to the present invention is a motorcycle in which rear wheel shock absorbers are arranged at 14 degrees in the center of the vehicle width, and the frame member provided at the rear end of the main frame is In this case, the left and right main frame rear ends are made into a substantially triangular shape consisting of a base connecting the rear ends of the left and right main frames in a substantially straight line, and both sides extending diagonally inward and upward from both rear ends, so that sufficient rigidity of the frame members can be ensured. can. In addition, when viewed from the side, it has an elongated shape that extends diagonally rearward and upward from the rear end of the main frame and intersects with the longitudinal direction of the shock absorber, making it easy to peek into the shock absorber from the side of the vehicle body. Also, since you can insert your hand into the buffer, the maintainability of the buffer is significantly improved.

[Brief explanation of drawings]

1 to 5 show a motorcycle having a body frame of the present invention, FIG. 1 is a sectional view taken along the line C-C in FIG. 5, and FIG. A view in the direction of arrow D in the removed state, Fig. 3 is A- in Fig. 5.
4 is a cross-sectional view taken along line B-B in FIG. 5, and FIG. 5 is a side view of the motorcycle. 6 and 7 show a motorcycle with a body frame according to another embodiment of the present invention, FIG. 6 is a sectional view taken along the line E-E in FIG. 7, and FIG. 7 is a side view of the motorcycle. It is a diagram. DESCRIPTION OF SYMBOLS 1... Main frame, 2... Engine, 3... Front wheel, 4... Rear wheel, 5... Head pipe, 6... Rear arm pivot, 7... Rear arm, 8... ...Frame member, 9...Buffer.

Claims (1)

[Claims] It has a pair of left and right main frames extending diagonally downward from the head pipe above the rear arm pivot, and a frame member is provided between the rear ends of the left and right main frames to connect these rear ends, and the frame member In the motorcycle in which I shock absorbers extending in the vertical direction are disposed between a rear arm and a rear arm, the frame member has a bottom side that connects rear end portions of the left and right main frames in a substantially straight line when viewed from the rear; A substantially triangular shape consisting of both sides extending diagonally inward and upward from the rear end, and extending diagonally rearward and upward from the rear end of the main frame when viewed from the side, and intersecting the longitudinal direction of the shock absorber. A motorcycle body frame characterized by comprising: