JP3036420U - Foldable bicycle frame - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide a foldable bicycle frame which is easy to remove, fold and install a handle. A frame of a folding bicycle according to the present invention includes a front frame and a rear frame. The rear frame includes a rear lower fork pipe 11, a rear upper fork pipe 12,
The seat tube 14 and the horizontal axis tube 13 are provided, and the front frame 20 is provided with an upper tube 21, a lower tube 22 and a head tube 23. Among them, the rear frame 10 is provided with an upright shaft tube 15 beside the horizontal shaft tube 13, and the upper tube 21 of the front frame 20 is a curved tube having a downward concave shape, and its rear end has an appropriate length. The upper seat pipe 25 is connected coaxially with the seat pipe 14 having
It can be pivotally pivoted therein for rotation, so that the front frame 20 and the rear frame 10 can be relatively rotated and folded.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a foldable bicycle, and more particularly to a foldable bicycle frame.

[0002]

[Prior art]

 As can be seen from the conventional technology, the conventional foldable bicycle usually includes a joint structure that folds the vehicle body (frame) and a joint structure that folds the handlebar, and the foldable joint structure is generally a hinge (or a negative type). The pivotal structure of (referred to as) is adopted. That is, two symmetrical metal members are provided at the folding position of the frame, and the side ends of the two metal members are pivotally connected to each other by pins so that they can rotate with respect to each other.

[0003]

[Problems to be solved by the device]

 However, the hinge joint of such a foldable bicycle has the following drawbacks. 1. Since the hinge joints tend to loosen, the rigidity of the frame is insufficient. 2. The hinge joint must be fixed by relying on a special tightening structure and operating method, which structure is fragile and convenience is affected. 3. These traditional hinge joints are often special in shape, which affects the overall appearance of the bicycle.

A main object of the present invention is to provide a foldable bicycle frame, which has a frame structure similar to that of a general bicycle and has a curved pipe structure, and has a rigid connection and is convenient to use. A second object of the present invention is to provide a foldable bicycle frame which is easy to use for removing, folding and mounting the handle.

[0005]

The main features of the folding bicycle frame of the present invention include a front frame and a rear frame. Among them, the rear frame is provided with a seat pipe located at a connecting position of the front and rear frames, and an upright shaft pipe located at the bottom end of the seat pipe of the rear frame is provided. The front frame includes an upper pipe and a lower pipe, and the rear end of the lower pipe is pivotally connected to the rear frame shaft pipe so that they can rotate relative to each other, and the rear end of the upper pipe is separately coaxial with the seat pipe. A seat pipe is provided, which allows the fixed position of the seat rod to be inserted, the front ends of the upper and lower pipes are welded to the head pipe, and the supporting pipes are welded in the middle to make the front frame rigid. The structure is such that it can rotate relative to the rear frame.

Another feature of the foldable bicycle frame of the present invention is that the frame has an inner tube at the top end of the fork, and the handle stem has an outer tube of appropriate length, which is the outer tube. On the rear side of the tube, there is a clamping ear that is used to attach the quick release bolt, which is just attached to the inner tube and fastened with the quick release bolt to be attached or removed.

[0007]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, as shown in FIGS. 1 and 2, one embodiment of the foldable bicycle frame of the present invention includes a rear frame 10 and a front frame 20. The rear frame 10 is composed of a rear lower tube 12, a horizontal shaft tube 13 and a seat tube 14, of which an upright shaft tube 15 is attached to the bottom end of the seat tube 14 to freely rotate. The front frame 20 is composed of an upper tube 21, a lower tube 22, a head tube 23 and a supporting tube 24, in which the upper tube 21 is a curved tube which is recessed downward, and its rear end has an appropriate length. An upper seat tube 25 is provided and located on the axis of the seat tube 14, which is exactly the same axis as the seat tube 14 and is fixed so that a seat post 26 is inserted and does not move. The rear end of the lower pipe is welded to the upright shaft pipe 15 and pivotally connected to the rear frame 10.

In the frame of the folding bicycle according to the above-described embodiment, the lower pipe 22 of the front frame is connected to the upright shaft pipe 15 of the rear frame so that the front and rear frames rotate relative to each other. When riding a bicycle, as shown in FIG. 1, the seat rod 26 is simultaneously inserted into the upper seat tube 25 and the seat tube 14 so that the front and rear frames are fixed and tightened. When the frame is folded, the front frame can rotate about the upright shaft tube 15 simply by pulling out the seat tube 26, and the upper seat tube 25 is separated from the seat tube 14 as shown in FIG. The folded state is completed, the operation is convenient enough, and the whole frame is assembled from the pipe, so it is structurally safe and robust.

As shown in FIGS. 3 and 4, another embodiment of the foldable bicycle frame of the present invention is generally the same as the structure of the above-described embodiment, which is the rear frame 30 and the front frame. 40, of which the rear frame also includes a rear lower pipe 31, a rear upper pipe 32, a horizontal shaft pipe 33 and a seat pipe 34. The front frame includes an upper tube 41, a lower tube 42, a head tube 43, a support tube 44, and an upper seat tube 45 located at the rear end of the upper tube 41. The difference from the above-mentioned embodiment is that a stretching pipe 35 extending forward is provided at the front end of the horizontal shaft pipe 33 of the rear frame, and an upright shaft pipe 36 is further provided at the front end of the stretching pipe 35. The lower bent portion of the lower pipe 42 is inserted into the upright shaft pipe 36, and the two pivotally connected members are relatively rotatable but inseparable, so that the front and rear frames 40, 30 are also relatively rotatable. When the seat rod 26 is inserted into the upper seat tube 45 and the seat tube 3, the frame is fixed in the used state as shown in FIG. If the seat rod 26 is extracted, the front and rear frames 40 and 30 can be folded relative to each other as shown in FIG.

Also, FIGS. 5 and 6 show an embodiment in which a handle system is attached to the frame of the folding bicycle of the present invention, which includes an inner pipe 50 and a handle stem 60. Reference numeral 50 is a straight pipe, the top end of which is expanded outwardly so that a washer 51 can be attached, the bottom end of which is a beveled face 52, and the bolt 53 is an inner pipe 50 and a washer 51 (in the center, The bottom end is further tightened to the slant wedge mass 52 by passing through (there are both holes), and the bolt 53 presses the slant wedge mass 54 and the slant cut surface 52 to cause the transition operation of the slant surface. The inner tube 50 is assembled into the head tube 23 and rotated with the fork 55, which construction is conventional.

The handle stem 60 is used for mounting a handle of a bicycle, which mainly has an outer tube 61, and a set of tightening ears 62 is provided on the lower rear side of the outer tube 61. The quick release bolt 63 is passed through the tightening ear 62, and when the outer pipe 61 is securely inserted into the inner pipe 50 from top to bottom, it is fastened with the quick release bolt 63, and when the handle stem 60 is removed, the quick release bolt 63 is removed. All that is required is to loosen the bolts 63, and when the frame is folded, the handle stem 60 should be placed near the upper tube or seat tube. Of course, since the outer pipe 61 and the inner pipe 50 are fitted to each other, convex points 56 which are fitted to each other and fixed in position may be provided between the contact surfaces corresponding to each other, if necessary.

Finally, FIG. 7 is a front view of the foldable bicycle frame of the present invention assembled to a bicycle, and FIGS. 8, 9 and 10 show the folding operation of the foldable bicycle frame. It is the represented top view. The operation can be folded simply by pulling out the seat rod 26, and the folding operation is completed by removing the handle stem 60, which is extremely easy.

As can be seen from the above description, the foldable bicycle frame of the present invention has a clever design, and the front and rear frames of the foldable bicycle are both constructed as a simple rigid structure and can be rotated relative to each other. It can be said that the structure is a new type of device because it can improve the drawbacks of the similar products.

[Brief description of the drawings]

FIG. 1 is a front view of a frame of a folding bicycle according to the present invention.

FIG. 2 is a front view of the folding bicycle frame of FIG. 1 folded.

FIG. 3 is a front view of another embodiment of the folding bicycle according to the present invention.

FIG. 4 is a front view of the folding bicycle frame of FIG. 3 in a folded state.

FIG. 5 is an exploded perspective view of the frame and the handle stem of the folding bicycle according to another embodiment of the present invention.

6 is a perspective view of a combination of the frame and the handle stem of the bicycle shown in FIG.

FIG. 7 is a front view of the frame of FIG. 3 combined with a bicycle.

FIG. 8 is a plan view of the bicycle shown in FIG.

FIG. 9 is a plan view of the bicycle shown in FIGS. 7 and 8 in a folded state.

FIG. 10 is a plan view of the handlebar stem of the folded bicycle of FIG. 9 in a detached state.

[Explanation of symbols]

 10 Rear frame 11 Rear lower pipe 12 Rear upper pipe 13 Horizontal shaft pipe 14 Seat pipe 15 Upright shaft pipe 20 Front frame 21 Upper pipe 22 Lower pipe 23 Head pipe 24 Support pipe 25 Upper seat pipe 26 Seat rod

Claims (4)

[Utility model registration claims] 1. A front frame and a rear frame, wherein the rear frame is composed of a rear lower pipe, a rear upper pipe, a seat pipe and a horizontal shaft pipe, and a front frame is composed of an upper pipe, a lower pipe and a head pipe. The upright tube is installed beside the horizontal axis tube of the rear frame, the upper tube of the front frame is a curved tube, and the upper seat tube is connected to the rear end of the upper tube, and the upper seat tube has a suitable length. It is a thick pipe that is coaxial with the seat pipe, and a supporting pipe is further provided between the upper pipe and the lower pipe of the front frame, and the rear end of the lower pipe is provided in the upright shaft pipe of the rear frame. The foldable bicycle frame, wherein the rear end of the pipe is pivotally connected to the upright shaft pipe of the rear frame, and the front and rear frames can rotate relative to each other. 2. The bottom end of the seat tube of the rear frame is located on a horizontal axis tube, which is provided with an upright axis tube for serving in combination with the rear end of the lower tube of the front frame. The frame of the folding bicycle according to claim 1. 3. The front edge of the horizontal axis tube of the rear frame is provided with an extension tube extending forward, and the upright axis tube is fixed to the front end of the extension tube so that the rear end of the lower tube of the front frame is 2. A foldable bicycle frame as claimed in claim 1, characterized in that it is provided for the penetration of an upright shaft tube as well as pivotally combined, for which the front and rear frames can rotate relative to each other. 4. A head tube is provided with an inner tube which can be rotated relative to each other in combination with a fork, the handle stem is provided for installation of the handle, and the outer tube can be just inserted into the inner tube. , The rear side is provided with a fastening ear portion used for installing a set of quick-release bolts, and the inner pipe located inside is clamped to be fixed in position. The foldable bicycle frame according to any one of 3 above.