JPH039506Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The present invention relates to frames for bicycles, especially children's bicycles.

Conventional technology Conventionally, bicycle frames are made by cutting a metal pipe to the required length to form a triangular frame body, connecting the frame body and a separately formed chain stay with a hanger lug, and connecting the chain stay and the vertical pipe. Generally, the spaces are connected with backbones to form a whole.

Problems that the invention aims to solve Conventional diamond-shaped bicycle frames have a large number of parts, and therefore require many welding points during construction, requiring a large number of man-hours to manufacture.This has the disadvantage of poor production efficiency and the inability to reduce natural production costs. be.

In particular, children's bicycle frames are smaller but have exactly the same number of parts as those for adults, so reducing production costs is the biggest challenge.

The present invention was developed with the aim of eliminating the disadvantages of conventional frame production as described above.

Means for Solving the Problem Long pipes having the required outer diameter and length are curved in parallel from the center, and the front half of the pipes are made parallel and close to each other, and bent upward in the front. The front end is integrally welded and connected to the head pipe to form the main body of the frame, and the rear part is bent and inclined rearward at a desired angle from a suitable point, and bent and separated so that the rear wheel can be placed between the pipes. The bicycle frame is characterized in that the ends are formed into chain stays that are connected in an annular manner, and a hanger lug with a seat pipe welded and connected to the intermediate upper surface is passed and welded thereto.

Function As mentioned above, this project is made by folding a single long pipe in half and constructing the main body of the frame in the front half and the chain stay in the rear half, so unlike the conventional frame, there are no welded parts. , compared to the case of conventional frame manufacturing, the connecting part with the head pipe 3 at the front end of the frame main body and the reinforcing connecting leg piece 6 of the hanger lug 5 to which the seat pipe 4 is attached are welded between the parallel frame main bodies, There are significantly fewer welded parts and fewer component parts.

Example The present invention will be explained below with reference to an example shown in the drawings.A single metal pipe having the required external shape and length is curved from the center on the same plane at the required radius, and then folded in two. The front half parts of approximately 1/2 length are arranged in parallel and close to each other to form a frame main body 1,
The rear part is formed into an annular chain stay 2 having a required inner width. And frame main body 1
is bent forward at a required angle and the front end is welded and connected to the head pipe 3, and the chain stay 2 is bent and inclined backward at a required angle from the part connected to the main body of the frame. In addition, a hanger lug 5, to which a seat pipe 4 is welded and connected, is passed and welded to the connecting portion between the frame main body 1 and the chain stay 2. Note that 6 is a reinforcing connecting leg piece that is welded between the parallel pipes to reinforce the welding between the hanger lug 5 and the frame main body 1.

Effects As mentioned above, this project is made by folding one long pipe in half and constructing the main body of the frame and the chain stay as one body, which is different from the conventional diamond frame in which multiple pipes are connected. It is something with an original shape.

Therefore, since the rear end of the chain stay is bent and connected, the entire structure can be created by simply welding the front end to the head drag, joining it in an annular shape, and welding the hanger with the seat post attached between them. It is possible to significantly reduce the In addition, since the hanger lug is welded across the top of the connecting part between the main frame and the chain stay, it not only reinforces the main frame but also allows this part to be placed as low as possible, making it easy to get on and off the bicycle, especially , Since children's bicycles are equipped with auxiliary wheels and can stand on their own, the effect is great. Furthermore, the reinforcing connecting legs can be fitted and welded between the pipes that constitute the frame main body, thereby significantly improving the welding strength between the frame main body and the hanger. In addition, since the rear ends of the chain stay are connected to the left and right, it protects the rear wheels from the shock when the bicycle falls sideways, which is especially effective for children's bicycles, which often fall over.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a side view and FIG. 2 being a plan view. 1... Frame main body, 2... Chain stay, 3
...Head pipe, 4...Seat pipe, 5...
hanger rug.

Claims (1)

[Scope of utility model registration request] Long pipes having the required outer diameter and length are curved in parallel from the center, the front half of the pipes are parallel to each other and close to each other, and the front ends are bent forward and upward, and the front ends are integrally attached to the head pipe 3. The rear part is bent and tilted upward at a required angle from a proper place, and the rear wheel is bent and separated so that a rear wheel can be placed between the pipes, and the rear end is connected in an annular shape. A hanger lug 5 formed on a chain stay 2 with a seat pipe 4 welded and connected to the intermediate upper surface.
A bicycle frame characterized by being welded together.