JPS6036987B2 - Motorcycle body frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a main body formed by a pipe framework.
The present invention relates to a body frame for a motorcycle, such as a cradle type body frame.

Generally, the vehicle body frame is required to have sufficient rigidity, be lightweight, and reduce manufacturing costs.

By the way, a conventional cradle type vehicle body frame, for example, has a pair of left and right pillars 011, which are suspended downward from both sides of the middle part in the longitudinal direction of the upper frame, as shown in FIGS. 5 and 6.
The lower end of 011 and the lower ends of down tubes 010, 010 extending downward and rearward from the head pipe 01 are joined together by a cross pipe P that is thicker than these to obtain the necessary rigidity of the lower part of the body frame. A drain hole 015 for the pre-treatment liquid for painting the vehicle body frame is drilled in the middle part of the lower surface of the pipe P, and a rear lower engine hanger or main instant brackets 016 and 016 are welded to the cross pipe P. Ta. In order to obtain the required rigidity of the lower part of the conventional body frame, down tubes 010, 010 and pillars 011, 01 are used.
Not only does this require a cross pipe P that is thicker than 1, but also a drain hole 015 is formed therein, which not only increases the weight of the vehicle body frame but also increases manufacturing costs. Therefore, the present invention provides a motorcycle with a simple structure, which can maintain the necessary rigidity in the lower part of the body frame without using the conventional cross pipe, and eliminate the above-mentioned problems by eliminating the need to process the liquid drain hole. The purpose of this project is to obtain a vehicle body frame for use.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 4.

In this embodiment, the present invention is applied to a cradle-type vehicle body frame, and the front end of a main pipe 3 is welded via a stay 2 to a head pipe 1 through which a steering shaft is inserted. It extends rearward approximately horizontally, and a fork-shaped back frame 4 is welded to its rear end. Constructed by combining.

Further, a gusset 9 is welded to the main pipe 3 over substantially its entire length, and this gusset 9 is attached to the main pipe 3.
and together with the main pipe 3 constitutes an oil tank T. The main pipe 3, gusset 9 and back frame 4 constitute an upper frame Fu of the vehicle body frame. In addition, the head pipe 1
The upper ends of the two left and right down tubes 10, 10 are welded to each other via the stay 2, and these down tubes 10, 10 form a substantially L-shape and extend downward and rearward.

A pair of left and right pillars 11, 1 are provided at the front and rear intermediate portions of the upper frame Fu, that is, on both sides of the front end of the back frame 4.
The upper ends of the pillars 11, 11 are welded to each other, and the middle portions of these pillars 11, 11 are connected to the cross member 12, as clearly shown in FIG.
The lower half portion is bent forward to form a substantially dogleg shape, and the rear ends of the left and right down tubes 10, 10 are respectively docked at the lower end portions of the down tubes. The main pipe 3, the down tube 10,
10 and the pillars 11, 11 form a housing for the engine. The lower end portions of the pair of left and right pillars 11, 11 are each bent inward at a substantially right angle and arranged vertically in a substantially straight line, and the inner bent ends 11a
, 11a are opposed to each other with a small gap C as shown in FIG. Further, the bent ends 11a, 11a of the pair of left and right pillars 11, 11 are integrally connected by a connecting member 13 that is placed across them. The coupling member 13
is formed into a notched hollow cylindrical shape with a notch 14 on its lower surface, and a fourth
As shown in the figure, a drain hole 15 is formed, and this drain hole 15
Pre-treatment liquid for painting the car body frame is drawn out through.
Further, a pair of rear lower engine hangers or main stand brackets 16, 16 are integrally molded or attached to the connecting member 13, and the rear lower engine hangers 16, 1
6 is the front down tube 10, 10 and the pillar 11, 11
The engine housed in the framework can be suspended with front engine hangers 17, 17 and rear upper engine hangers 18, 18, which are respectively welded to the frame. Backstays 19, 19 are installed between the left and right pipes 5, 5 of the back frame 4, and between the left and right pillars 11, 11, respectively. In addition, in the figure 20, 2 river rear fork bracket, 21
, 21 are slap brackets.

As described above, according to the present invention, in a motorcycle body frame whose main portion is constituted by a pipe framework, a pair of pillars 1 1, 11 are integrally suspended from both sides of the front and rear intermediate portions of the upper frame Fu. The lower ends of the platoons C are bent inwardly, and the inner bent ends 11a, 11a of the platoon C are arranged in a substantially straight line.
A connecting member 1 in which a notch 14 is formed on the lower surface of the members a and 11a.
3, so even if the lower ends of the left and right pair of pillars 11, 11 are attached together with a long, large-diameter cross pipe as in the conventional example, high rigidity of the lower ends of the pillars can be obtained. can. In addition, a drain hole 15 for draining pre-treatment liquid for painting is formed by the inner bent ends 11a, 11a of the left and right pair of pillars 11, 11 and the connecting member 13, so that the drain hole 15 is formed in the cross pipe as in the conventional one. There is no need to drill or process the cross pipe, and together with the elimination of the cross pipe, manufacturing costs can be significantly reduced.

[Brief explanation of drawings]

1 to 4 show one embodiment of the present invention, FIG. 1 is an overall perspective view thereof, FIG. 2 is an exploded perspective view of a pair of pillars and a connecting member, and FIG. 3 is a view similar to that shown in FIG. 1. FIG. 4 is an enlarged vertical sectional view taken along the line mm, FIG. 4 is a view taken along the line W--W in FIG. 3, FIG. 5 is a perspective view of a conventional vehicle body frame, and FIG. 6 is an exploded perspective view of a portion thereof. C...Small gap, Fu...Upper frame, 11
......Pillar, 11a...Inner bent end,
13... Joint village, 14... Notch. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. In a motorcycle body frame whose main part is a pipe framework, in the upper frame, the lower ends of a pair of pillars 11, 11 are integrally suspended from both sides of the front and rear intermediate parts of the upper frame Fu. are bent inward to each other, and their inner bent ends 11a, 11
A body frame for a motorcycle, wherein the inner bent ends 11a, 11a are connected together by a connecting member 13 having a notch 14 formed on the lower surface. .