JPH0532275B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a frame structure for a motorcycle.

Pipe materials are characterized by their high rigidity, which allows them to support a large load compared to the proportion of space occupied by the pipe materials themselves. Therefore, this pipe material is suitable for use as a structural member that supports a large load in a narrow space, such as a seat rail that supports the seat of a motorcycle.

However, one of the problems when using such a pipe material for the seat rail is that the main pipe of the fuselage frame is made of the same pipe material, so it is difficult to directly fix the rear end of the main pipe to the cylindrical side of the seat rail. In some cases, there is a problem in that it is extremely difficult to fix the two to accurately determine their positional relationship. Another problem is that the rider's weight is applied to the seat rail as it changes from front to back and from side to side. It is necessary to reinforce and fix a plurality of brackets as auxiliary materials, which inevitably increases the weight of the aircraft body.

The purpose of the present invention is to solve the above-mentioned problems when using pipe materials for seat rails, to fully utilize the inherent rigidity of the pipe materials, to avoid unnecessarily widening the aircraft frame width, and to be lightweight. An object of the present invention is to provide a frame structure for a motorcycle that allows a seat rail to be connected to a main pipe with high precision while achieving a high degree of efficiency.

The present invention achieves the above object by connecting seat rails made of two left and right pipes to the rear ends of the two left and right main pipes constituting the aircraft frame through two left and right plate members, respectively. The two left and right plate members are each bent into a stepped shape such that the gap between the two plate members is wider on the upper side and narrower on the lower side, and the seat rail is attached to the inner surface of the upper part of the plate member. and fixing the rear end of the main pipe to the outer surface of the lower part of the plate member,
Furthermore, the present invention is characterized in that the upper end of the shock absorber for the rear wheel is pivotally supported on the plate member.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 1 shows a relatively small-sized motorcycle having a frame structure according to the present invention. In FIG. 1, numeral 1 is a main pipe constituting the frame, two of which are provided on the left and right sides, and numeral 2 is a head pipe fixed to the front side of the main pipe. 3 is a seat, 4 is an engine, 5 and 6 are front wheels and rear wheels, respectively, and 7 is a shock absorber for the rear wheel 6.

FIG. 2 shows the frame of the above-described motorcycle, and FIGS. 3 and 4 are enlarged views of the portion indicated by arrow A in FIG. 2, showing details of the joint structure between the seat rail and the main pipe.

As shown in the figure, there are two main pipes 1 on the left and right,
Seat rails 9, 9 made of pipe material are fixed to the upper rear end of the seat 1 by welding via plate members 8, 8, respectively. Sheet suction cup holders 10, 10 for receiving suckers (not shown) are welded and fixed, respectively.

As shown in FIG. 4, the plate members 8, 8 are bent with stepped portions 8a, 8a provided in their intermediate portions, and the spacing between them facing each other is widened on the upper side and narrowed on the lower side. There is. At the upper ends of the wide plate members 8, 8, seat rails 9, 9 are fixed to the inner surfaces thereof in a wide width in the left and right directions, so that the seat 3 can be stably supported in the left and right direction. Further, on the lower sides of the plate members 8, 8 with a narrower interval, a main pipe 1 whose tip is crushed into a flat plate shape is welded and fixed to both outer surfaces thereof. In this way, the left and right plate members 8, 8 are bent in a stepped manner so that the gap between them is wider on the upper side and narrower on the lower side, and the seat rail 9 is bent in the upper part with respect to this plate member 8. Since we welded the main pipe 1 to the inner surface of the side, and the main pipe 1 to the outer surface of the lower side,
It is possible to make the aircraft frame more compact without making it unnecessarily wide.

Moreover, by using this plate member 8, the seat rail 9 can be fixed while maintaining its pipe shape, so that the large rigidity of the pipe material itself can withstand loads in either the horizontal or vertical direction. It can also be demonstrated against. Also,
During the fixing work, the seat rail 9 is not directly fixed to the main pipe 1, but is welded to the planar plate member 8, so that accurate positioning can be achieved. Furthermore, since the plate member 8 is bent in a stepped manner, it has great rigidity, and the seat rail 9 can be easily fixed without using a bracket or the like as a reinforcing material.
can be firmly connected to the main pipe 1. Therefore, the weight of the aircraft body can be reduced without causing an increase in weight due to the addition of extra parts.

In addition, a cross bar 11 is supported across the left and right portions of the plate members 8 and 8 on the lower side where the interval width is narrow as described above, and the cross bar 11
Pivot supports 7a, 7a of shock absorbers 7, 7 are rotatably supported on both sides of the buffer. In this way, the buffer 7
By supporting the pivot portion 7a on the outer surface of the lower part of the narrow plate member 8, the spacing between the left and right shock absorbers 7, 7 can be set to an appropriate width corresponding to both ends of the axle of the rear wheel 6. It becomes possible to support. That is, if the pivot parts 7a, 7a of the shock absorbers 7, 7 are supported on both outsides of the main pipes 1, 1, a problem will arise in that the spacing between the shock absorbers 7, 7 is too wide. According to the configuration, such over-spreading can be avoided. Moreover, if the pivot parts 7a, 7a of the shock absorbers 7, 7 are to be supported on both outsides of the main pipes 1, 1, supporting holes must be drilled in the main pipes themselves, and the main pipes This also results in the problem of weakening the strength of the material.

As described above, in the frame structure of the present invention, two plate members on the left and right are interposed to connect the seat rail made of the two left and right pipes to the rear ends of the two left and right main pipes. Therefore, position fixation does not become unstable as in the case of direct connection, and highly accurate positioning is possible. In addition, since the seat rail can be fixed while maintaining the pipe shape, the high rigidity inherent in the pipe material can be applied to loads in both the horizontal and vertical directions, making it possible to stably support the seat. Make it.

Further, the two left and right plate members are each bent into a stepped shape so that the gap between the two plate members is wider on the upper side and narrower on the lower side, and the seat rail is fixed to the inner surface of the upper part of the plate member. In addition, since the rear end of the main pipe is fixed to the outer surface of the lower part of the plate member, the fuselage frame can be made compact without increasing the width unnecessarily.
Furthermore, since the rigidity in the horizontal and vertical directions is improved by bending the plate members, a strong connection is possible without additionally using reinforcing members such as brackets, and the weight of the aircraft body can be reduced.

Further, in the present invention, since the upper end of the shock absorber of the rear wheel is pivotally supported on the plate member having the above-mentioned structure, the strength of the frame is not reduced unlike when a support hole is provided in the main pipe.

[Brief explanation of the drawing]

FIG. 1 is a side view of a motorcycle having a frame structure according to the present invention, FIG. 2 is a side view of the frame of the motorcycle, FIG. 3 is an enlarged side view of the portion indicated by arrow A in FIG. The diagram is in Figure 3-
FIG. 1... Main pipe, 3... Sheet, 7... Buffer, 7a... Pivotal part, 8... Plate member, 8a...
Stepped part, 9... Seat rail.

Claims (1)

[Claims] 1. A seat rail 9 made of two left and right pipes is connected to the rear ends of two left and right main pipes 1 constituting the aircraft frame via two left and right plate members 8, respectively. The two plate members 8 are each bent into a stepped shape such that the interval between the plate members 8 is wider on the upper side and narrower on the lower side, and the seat rail 9 is fixed to the inner surface of the upper part of the plate member 8. At the same time, the rear end of the main pipe 1 is fixed to the outer surface of the lower part of the plate member 8, and the upper end of the rear wheel shock absorber 7 is pivotally supported on the plate member 8.