JPS60213588A - Frame for bicycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a joint of constituent members of a bicycle frame.

This invention aims to reduce manufacturing costs by standardizing bicycle frame components into a small number of items, and also rationalizes the shape of the joints of the components to ensure uniform and reliable brazing of the joints, thereby improving the bicycle frame. It was created with the aim of providing high quality at low cost.

Conventionally, bicycle frames have been made by joining pipes with joint tracks, but since all joint parts of joint tracks are formed in a 2) rate, if there is a problem with the joint, the pipe that fits with this joint A non-uniform gap is formed between the parts and the solder, which results in poor soldering during brazing, which can lead to defects in brazing. In addition, the joining angles of the frame components differ depending on the frame size, purpose, and other reasons, and there is a drawback that joint tracks must be prepared for each type of frame.

Hereinafter, this invention will be explained with reference to drawings which are examples.
Reference numeral 1 denotes a bicycle frame, which is composed of a frame body 2 and a front fork 3 as shown in the figure.

As shown in FIG.
, Seat lug 9,) Pipe lug 13, Upper pipe 5
, lower pipe 7, standing no.
, 17. The head knob 4 is a connecting part 6 of the head upper rack that connects the upper pipe 5 and the lower pipe 7.
And the connecting part 8 of the rack on the head, the seat lug 9 is on the top) (the connecting part 11 of the Eve 5, the hanger lug 13 is on the bottom).
Connecting portions 14.15.1B and 19 are provided in a protruding manner.

Each of the above-mentioned connecting parts is formed into a taper shape whose outer diameter decreases toward the tip, and is shown as a conical head in the drawing. However, its shape is spherical as shown in Figs. 5 and 6. Although not shown, deformation into an elliptical cone or other shape to protrude may be possible within the scope of achieving the technical purpose of the present invention.

End portions 5a, 5b of the upper pipe 5, lower pipe 7, vertical pipe 10, and chainstays 16, 17, respectively;
7a, 7h.

10a, 16a, and 17a are expanded into a trumpet shape with a maximum diameter at the tip, and each is formed in a shape to fit into the connecting portion of the join track.

When the connecting portion of the joint track is formed in a spherical shape, the inner diameter of the end of the pipe is expanded into a spherical shape, as shown in FIGS. 5 and 6.

The shape of the inner diameter surface of the pipe end can also be modified in the same way as the connecting surface of the join drag.

When manufacturing frames of different sizes using the same head pipe, the axis of the end of the pipe is bent relative to the join track, as shown in FIGS. 4 and 9.

In addition, when correcting the angle of the connecting part of a conventional join track, as shown in Figure 7, it is done by inserting a correction rod and tilting it to the desired angle side, and the inner (3) diameter expands into a fan shape. It is.

As described above, the present invention is as described above, and the joint track and the pipe fit together on the outside, and the connecting surfaces of the two are in uniform contact with each other, and there are no gaps between them, so brazing is not a process. In this case, the solder spins easily, and therefore there are fewer defective products, which improves productivity and eliminates variations in quality.

Additionally, by bending the axis of the end of the pipe, joint tracks can be standardized into a small number of items, allowing the manufacture of many frames of different sizes, which is extremely effective in reducing manufacturing costs. .

In addition, joint track has bulge, lost wax,
Mariable can also be produced by various processing methods, and its dimensional accuracy is high and accurate. By processing, it can also be formed as desired.

Therefore, according to the present invention, the manufacturing cost of the bicycle frame (4) is reduced, and the strength of the joints is increased, resulting in high quality.

[Brief explanation of the drawing]

Fig. 1 is a side view of a bicycle frame joined according to the present invention, Fig. 2 is an exploded perspective view of the frame body, Fig. 3 is a side view of the upper pipe alone, and Fig. 4 shows that the axis of the end is bent. A side view showing an example of a single lower pipe when bending, FIG. 5 is a perspective view of parts showing another example, and FIG. 6 is a partial vertical sectional view thereof.
Figure 7 is a sectional view showing a modified example of a conventional join track, Figure 8 is a perspective view showing an example of a processing method for widening the end of a pipe, and Figure 9 is a bending of the axis of the end. FIG. 1... Bicycle frame 2... Frame body 3... Front fork 4... Head pipe 5... Upper vibro... Head upper rack connection part 7... Lower pipe 8... Head lower rack connection section 9 Seat lug 10 Standing pipe 11 Seat lug upper pipe connection section 13 Hanger rack 14 Lower pipe connection section 15 Standing pipe connection section 16 .17... Chain stay 16a, 17a... Chain stay one end 18.19...
・Chenoste Connection Department Applicant: Miyata Kogyo Co., Ltd. Agent: Kan Ohga, Masayoshi Masuda

Claims (5)

[Claims] (1) At the joint of the members constituting the bicycle frame, the joint track is provided with a protruding joint, and the inner diameter of the end of the pipe to be joined to the joint is an enlarged surface that fits and connects with the joint. A bicycle frame in which the connecting surfaces are brazed together after the two are fitted together. (2) The bicycle frame according to claim 1, wherein the connecting portion of the join track is provided in a tapered projecting shape. (3) The bicycle frame according to claim 1, wherein the connecting portion of the joint track is formed to protrude into a hemispherical surface. (4) The widening surface of the inner diameter of the end of the pipe corresponds to the joint part of the joint track having a tapered protrusion,
The bicycle frame according to claim 1, characterized in that it has a trumpet shape. (5) The bicycle frame according to claim 1, wherein the expanding surface of the inner diameter of the end of the pipe has a spherical shape corresponding to the spherical protrusion of the connecting portion of the joint. .