CN114013551B

CN114013551B - Small comfortable folding bicycle

Info

Publication number: CN114013551B
Application number: CN202111435404.XA
Authority: CN
Inventors: 吴振坚
Original assignee: Computer Aided Engineering Mobile Consulting Co ltd
Current assignee: Computer Aided Engineering Mobile Consulting Co ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2023-03-31
Anticipated expiration: 2041-11-29
Also published as: CN114013551A

Abstract

The invention discloses a small and comfortable folding bicycle, which comprises a main supporting pipe, wherein the front end of the main supporting pipe is provided with a single-fork front wheel steering mechanism, the rear end of the main supporting pipe is provided with a seat pipe, the top of the seat pipe is provided with a telescopic seat cushion, the seat cushion is positioned above the main supporting pipe, the seat pipe is also provided with a rear wheel steering mechanism, and the rear wheel steering mechanism is positioned below the main supporting pipe; the front wheel section and the rear wheel section of the main supporting pipe are connected through a double-hinge mechanism, so that the front wheel section and the rear wheel section can be folded into a U shape; the double hinge mechanism has a locking mechanism that selectively fixes the front wheel section and the rear wheel section. The double-hinge mechanism is connected and matched with the single-fork front wheel steering mechanism, so that the folding is more compact, the occupied space is small, the hinge is arranged, the structure is simple, excessive protrusion of the main support pipe is avoided, and the smoothness of the vehicle body is improved; and the handlebars, the head tube and the pedals in the bicycle can be folded, so that the occupied space after folding is further reduced, and the bicycle is convenient to transport and store.

Description

Small comfortable folding bicycle

Technical Field

The invention relates to the technical field of bicycles, in particular to a small and comfortable folding bicycle.

Background

In the traditional bicycle, the front wheel and the rear wheel are positioned on different planes or have height difference after being folded, so that the bicycle body cannot move through the wheels and needs to be manually carried; because the bicycle overall structure is great, heavier to make the bicycle transport after folding comparatively difficult.

The middle part of a main support pipe of a bicycle frame is provided with a folder to realize a folding function, and the folder is generally larger than the section of the main support pipe of the bicycle frame and can be integrally protruded, so that the overall appearance of the bicycle is not smooth, and the aesthetic feeling is influenced; still go out to have and set up the pivot in the below of main tributary stay tube, the rear wheel frame passes through the pivot, realizes folding forward, but this structure need take up the seat pipe before folding just collapsible, and seat pipe one side downward sloping easily simultaneously, folding process is complicated, be unfavorable for the transport.

Therefore, there is a need to develop a new technical solution to solve the above problems.

Disclosure of Invention

In view of the above, the present invention is directed to the disadvantages of the prior art, and a primary object of the present invention is to provide a small and comfortable folding bicycle, in which a front wheel section and a rear wheel section of a support tube are connected by a double-hinge mechanism and are matched with a single-fork front wheel steering mechanism to be folded into a "U" shape, so that the folding is more compact, the occupied space is small, the hinge is arranged, the structure is simple, the main support tube does not protrude too much, and the smoothness of the bicycle body is improved.

In order to achieve the purpose, the invention adopts the following technical scheme:

a small and comfortable folding bicycle comprises a main supporting pipe, wherein a single-fork front wheel steering mechanism is arranged at the front end of the main supporting pipe, a seat pipe is arranged at the rear end of the main supporting pipe, a telescopic seat cushion is arranged at the top of the seat pipe and is positioned above the main supporting pipe, a rear wheel steering mechanism is also arranged on the seat pipe and is positioned below the main supporting pipe;

the front wheel section and the rear wheel section of the main supporting pipe are connected through a double-hinge mechanism, so that the front wheel section and the rear wheel section can be folded into a U shape; the dual-hinge mechanism has a locking mechanism that selectively secures the front and rear wheel sections.

As a preferred scheme, the double-hinge mechanism comprises a connecting pipe and two hinges arranged on one side of the connecting pipe, one ends of the two hinges are connected to the connecting pipe, the other ends of the two hinges are respectively connected to the front wheel section and the rear wheel section, the locking mechanism is arranged on the other side of the connecting pipe, the locking mechanism comprises two racks and a rotating button meshed between tooth parts of the two racks, and the rotating button drives the racks to move relatively or oppositely to lock the front wheel section and the rear wheel section rotationally.

As a preferable scheme, the single-fork front wheel steering mechanism comprises a head pipe, a handlebar assembly arranged at the upper end of the head pipe and a front wheel assembly arranged at the lower end of the head pipe; the front wheel subassembly is including front wheel mounting bracket and front wheel, the front wheel mounting bracket is horizontal "A" font, the front wheel mounting bracket articulates the suspension stay tube in the one end of front wheel single fork including front wheel single fork and one end, the other end of front wheel single fork is connected in head pipe lower extreme, the front wheel is connected in the other end of suspension stay tube, the other end of suspension stay tube still is provided with the braking system who is used for the brake, press from both sides between front wheel single fork and the suspension stay tube and be equipped with first suspension bumper shock absorber.

As a preferred scheme, the handlebar assembly comprises a telescopic faucet pipe arranged at the upper end of a head pipe and a faucet hinged at the upper end of the faucet pipe, the faucet comprises a main rod with one end hinged to the faucet pipe and two supporting rods connected to the other end of the main rod, the two supporting rods can rotate relative to the main rod, and one end, far away from the main rod, of each supporting rod is connected with a handle.

Preferably, the ends of the two limbs adjacent the spine are selectively connectable.

As a preferred scheme, rear wheel steering mechanism is including rear wheel installation pipe, rear wheel installation pipe sets up on the seat pipe, rear wheel installation pipe is provided with bicycle crank subassembly, rear wheel support link assembly and rear wheel, bicycle crank subassembly and rear wheel support link assembly are located the front side, the rear side of seat pipe respectively.

As a preferred scheme, the rear wheel support link assembly comprises a rear upper fork and a rear lower fork, one end of the rear upper fork is hinged to the seat tube through a second suspension shock absorber, the other end of the rear upper fork is connected with one end of the rear lower fork, the other end of the rear lower fork is hinged to the rear wheel mounting tube, a first support reinforcing member is clamped between the rear upper fork and the rear lower fork, and the rear wheel is connected to the rear lower fork.

Preferably, the bicycle crank assembly comprises a bicycle crank, two foldable pedals connected to the bicycle crank, and a chain connecting the bicycle crank and the rear wheel, and the rear lower fork is further provided with a speed changer for changing speed of the chain.

As a preferred scheme, the front end of the rear wheel mounting pipe is connected with the main supporting pipe through a second supporting reinforcing part, and the first supporting reinforcing part and the second supporting reinforcing part are both arranged in a hollow manner.

Preferably, the bottom of the seat tube is provided with a walking wheel which is arranged in a telescopic way.

Compared with the prior art, the invention has obvious advantages and beneficial effects, and specifically, the technical scheme includes that:

the front wheel section and the rear wheel section of the supporting tube are connected and matched with the arrangement of the single-fork front wheel steering mechanism through the double-hinge mechanism and are folded into a U shape, so that the folding is more compact, the occupied space is small, the hinge is arranged, the structure is simple, the main supporting tube does not protrude too much, and the smoothness of a vehicle body is improved;

secondly, the front wheel mounting frame is in a transverse A shape, the front wheel single fork, the suspension support tube, the braking system and the first suspension shock absorber are integrally arranged, the structure is compact, the whole weight is reduced due to the arrangement of the front wheel single fork, the vibration of a vehicle body is reduced due to the arrangement of the first suspension shock absorber, and the riding is more comfortable;

the faucet comprises a main rod and two supporting rods, wherein one end of the main rod is hinged to a faucet pipe, the two supporting rods are connected to the other end of the main rod and can rotate relative to the main rod, and one end, far away from the main rod, of each supporting rod is connected with a handle; the whole faucet can adjust different angles and heights to adapt to the ergonomics of different people, the supporting rod can rotate, and when the bicycle is folded, the whole bicycle is more compact and occupies small space;

and the bottom of seat pipe has the walking wheel of retractable setting, when the transport, will walk the wheel and release downwards and contact ground, for the automobile body formation support after folding on the one hand, has avoided the phenomenon of seat pipe one side downward sloping, does benefit to whole transport simultaneously.

To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Drawings

FIG. 1 is a perspective view (unfolded state) of the preferred embodiment of the present invention;

FIG. 2 is a perspective view (unfolded state) of another perspective of the preferred embodiment of the present invention;

FIG. 3 is a top view of a preferred embodiment of the present invention (unfolded state);

FIG. 4 is a schematic view of a dual hinge mechanism according to a preferred embodiment of the present invention;

FIG. 5 is a schematic view of another perspective of the dual hinge mechanism of the preferred embodiment of the present invention;

FIG. 6 is a dual hinge mechanism (unlocked state) of the preferred embodiment of the present invention;

FIG. 7 is a dual hinge mechanism (locked state) of the preferred embodiment of the present invention;

FIG. 8 is a front wheel assembly (front wheel up position) of the preferred embodiment of the present invention;

FIG. 9 is a front wheel assembly of the preferred embodiment of the present invention (front wheel down position);

FIG. 10 is a front view of the preferred embodiment of the present invention (long arm operating condition);

FIG. 11 is a front view of the preferred embodiment of the present invention (short arm operating condition);

FIG. 12 is a schematic view of a handlebar assembly in accordance with a preferred embodiment of the present invention;

FIG. 13 is a schematic illustration of the articulation of the main shaft of the preferred embodiment of the present invention;

FIG. 14 is a schematic view of the connection of two struts according to the preferred embodiment of the present invention;

FIG. 15 is a schematic view of the preferred embodiment of the present invention with two struts separated;

FIG. 16 is a schematic view of a rear wheel steering mechanism in accordance with a preferred embodiment of the present invention;

FIG. 17 is a perspective view of the preferred embodiment of the present invention (stored folded, with the treadles unfolded);

FIG. 18 is a perspective view of the preferred embodiment of the present invention (storage collapsed, step collapsed);

FIG. 19 is a top view of the preferred embodiment of the present invention (stored folded state);

FIG. 20 is a side view (stored folded state) of the preferred embodiment of the present invention;

FIG. 21 is a perspective view (pushed folded) of the preferred embodiment of the present invention;

FIG. 22 is a schematic view of the head tube folded in accordance with the preferred embodiment of the present invention;

FIG. 23 is a schematic view of the folding of the bar in accordance with the preferred embodiment of the present invention;

FIG. 24 is a folding view of the dual-hinge mechanism of the preferred embodiment of the present invention.

The attached drawings indicate the following:

10. main support tube 11, front wheel segment

12. Rear wheel section 20, single fork front wheel steering mechanism

21. Head pipe 22 and handlebar assembly

221. Tap pipe 222 and tap

2221. Main rod 2222, branch rod

23. Front wheel assembly 231, front wheel mounting bracket

2311. Front wheel single fork 2312 and suspension support tube

2313. Brake system 2314, first suspension damper

232. Front wheel 24, lock nut

241. Prepressing spring

30. Seat tube 31, seat cushion

40. Double hinge mechanism 41, locking mechanism

411. Rack 412, tooth part

413. Rotary button 414, reset spring

42. Connecting pipe 43, hinge

44. Protective cover for locking mechanism

50. Rear wheel steering mechanism 51 and rear wheel mounting pipe

511. Second support reinforcement 52, bicycle crank assembly

521. Bicycle crank 522, pedal

523. Chain 53 and rear wheel support connecting rod group

531. Rear upper fork 532 and rear lower fork

533. Second suspension damper 534, first support reinforcement

54. Rear wheel 60, gear

70. And (4) a traveling wheel.

Detailed Description

Referring to fig. 1 to 24, there is shown a specific structure of a preferred embodiment of the present invention, which includes a main supporting pipe 10, a single-fork front wheel steering mechanism 20 provided at a front end of the main supporting pipe 10, a seat pipe 30 provided at a rear end of the main supporting pipe 10, a retractable seat cushion 31 provided at a top of the seat pipe 30, the seat cushion 31 being located above the main supporting pipe 10, a rear wheel steering mechanism 50 provided at the seat pipe 30, the rear wheel steering mechanism 50 being located below the main supporting pipe 10;

the front wheel segment 11 and the rear wheel segment 12 of the main support pipe 10 are connected by the double hinge mechanism 40, as shown in fig. 24, so that the front wheel segment and the rear wheel segment can be folded into a "U" shape, i.e., the single-fork front wheel steering mechanism 20 is folded backward to be parallel or nearly parallel to the rear wheel steering mechanism 50, or the rear wheel steering mechanism 50 is folded forward to be parallel or nearly parallel to the single-fork front wheel steering mechanism 20; the double hinge mechanism 40 has a lock mechanism 41 that selectively fixes the front wheel section 11 and the rear wheel section 12.

The invention can be applied to travel tools, leisure travel, sports, competitions and the like; the invention can be applied to different types of bicycles (such as small folding bicycles, mountain climbing bicycles, road bicycles, and the like) and electric bicycles; the bicycle of the invention can be applied to bicycle wheels with different sizes, shapes and materials (such as 14, 16, 18, 20, 24, 26 inches and the like); the different parts (such as the supporting tube, the handle, the wheel, etc.) of the bicycle of the invention can be made of different light materials (aluminum alloy, carbon graphite, titanium alloy, etc.); and screws and nuts of different models and sizes can be flexibly used for installation during assembly.

Specifically, the double-hinge mechanism 40 includes a connecting pipe 42 and two hinges 43 disposed on one side of the connecting pipe 42, one ends of the two hinges 43 are connected to the connecting pipe 42, the other ends of the two hinges 43 are respectively connected to the front wheel section 11 and the rear wheel section 12, the locking mechanism 41 is disposed on the other side of the connecting pipe 42, the locking mechanism 41 includes two racks 411 and a rotary button 413 engaged between teeth 412 of the two racks 411, the rotary button 413 drives the racks 411 to move relatively or oppositely to lock the front wheel section 11 and the rear wheel section 12 rotationally, and one rotary button 413 drives the two racks 411 to lock and unlock the two hinges 43 at the same time, so that the structure is simple; the locking mechanism 41 further includes two elastic resetting members 414, and the resetting force of the two elastic resetting members 414 faces the locking direction of the two racks 411, so that the two hinges 43 are always in the locking position to ensure safety; the main support tube 10 is also provided with a locking mechanism protective cover 44 for preventing any accidental activation of the rotation button 413, ensuring safe use of the bicycle; the main supporting tube 10 is matched with the two hinges 43, the bicycle is folded compactly, so that the main supporting tube 10 is folded into a U shape, and the front wheel and the rear wheel move in parallel and stably move in operation; and, the double-hinge mechanism 40 can be locked by using different locking mechanisms, which is not limited to the embodiment.

The single-fork front wheel steering mechanism 20 comprises a head pipe 21, a handlebar assembly 22 arranged at the upper end of the head pipe 21, and a front wheel assembly 23 arranged at the lower end of the head pipe 21, wherein the head pipe 21 is foldable as shown in fig. 22; the front wheel assembly 23 comprises a front wheel mounting frame 231 and a front wheel 232, the front wheel mounting frame 231 is in a transverse 'a' shape, the front wheel mounting frame 231 comprises a front wheel single fork 2311 and a suspension support pipe 2312, one end of the suspension support pipe 2312 is hinged to one end of the front wheel single fork 2311, the other end of the front wheel single fork 2311 is connected to the lower end of the head pipe 21, the front wheel is connected to the other end of the suspension support pipe 2312, a braking system 2313 for braking is further arranged at the other end of the suspension support pipe 2312, the braking system 2313 can adopt different types of braking system mechanisms (such as a wiring breaking disc, a hydraulic breaking disc and the like), and a first suspension damper 2314 is clamped between the front wheel single fork 2311 and the suspension support pipe 2312 (the first suspension damper 2314 can be a spring damper, a hydraulic damper, a pneumatic damper, a PU damper and the like). The design of one main support tube 10 can help to reduce the weight of the bicycle, and the front wheel adopts a front wheel single fork 2311 design to further reduce the bicycle weight; the provision of the first suspension damper 2314 makes riding more comfortable.

Handlebar assembly 22 sets up in the tap pipe 221 of head pipe 21 upper end, articulates in tap 222 of tap pipe 221 upper end including the retractable, tap 222 articulates in the mobile jib 2221 of tap pipe 221, connects in two branch 2222 of the mobile jib 2221 other end, and two branch 2222 accessible multiple mechanisms are rotatory relatively to the mobile jib 2221, the one end that mobile jib 2221 was kept away from to branch 2222 is connected with the handle, the articulated department of mobile jib 2221 is provided with the retaining member, the retaining member is lock nut 24, lock nut 24's locking head is the butterfly, and the manual locking or the unblock of people of being convenient for, lock nut 24 has pre-compaction spring 241, makes the installation more firm, the retaining member also can adopt other locking methods, does not use this embodiment as the limit. The main rod 2221 is hinged to the faucet pipe 221, and the height of the faucet 222 can be adjusted up and down to adapt to different human ergonomics, but the material and shape of the main rod 2221 are not limited thereto.

The rear wheel steering mechanism 50 comprises a rear wheel mounting pipe 51, the rear wheel mounting pipe 51 is arranged on the seat pipe 30, the rear wheel mounting pipe 51 is provided with a bicycle crank assembly 52, a rear wheel supporting connecting rod assembly 53 and a rear wheel 54, and the bicycle crank assembly 52 and the rear wheel supporting connecting rod assembly 53 are respectively positioned on the front side and the rear side of the seat pipe 30;

the rear wheel support link assembly 53 comprises a rear upper fork 531 and a rear lower fork 532, one end of the rear upper fork 531 is hinged to the seat tube 30 through a second suspension damper 533 (the second suspension damper 533 can be a spring damper, a hydraulic damper, a pneumatic damper, a PU damper, etc.), the other end of the rear upper fork 531 is connected to one end of the rear lower fork 532, and the other end of the rear lower fork 532 is hinged to the rear wheel mounting tube 51; the rear lower fork 532 is L-shaped, the rear upper fork 531 is connected to the short side end of the rear lower fork 532, and the rear wheel 54 is connected to the joint of the short side and the long side of the rear lower fork 532;

the bicycle crank assembly 52 comprises a bicycle crank 521, two foldable pedals 522 connected to the bicycle crank 521, a chain 523 connecting the bicycle crank 521 and the rear wheel 54, and the rear lower fork 532 is further provided with a speed changer for changing the speed of the chain 523. The main support tube 10, the faucet tube 221, the two support bars 2222 and the pedal 522 are arranged in a foldable manner, so that the occupied storage space is reduced as much as possible. Since the chain 523, the bicycle crank assembly 52, and the rear wheel 54 constitute one assembly unit, which does not involve the rotation of the rear wheel 54, the chain 523 is not easily detached during the folding process.

Preferably, a first support reinforcing member 534 is clamped between the rear upper fork 531 and the rear lower fork 532, the rear wheel 54 is connected to the rear lower fork 532, the front end of the rear wheel mounting tube 51 is connected to the main support tube 10 through a second support reinforcing member 511, and the first support reinforcing member 534 and the second support reinforcing member 511 are both hollow out, which is beneficial to reducing the weight of the bicycle;

and, the two supporting rods 2222 are both connected to the main rod 2221 through the end surfaces of the gears 60, and the two gears 60 can be engaged with each other (to ensure that the supporting rods 2222 are not easy to slip during the rotation process), when one supporting rod 2222 rotates, the other supporting rod 2222 also rotates relatively, so that the folding process is faster and smoother, and the two supporting rods 2222 may also be connected to the main rod 2221 by using other structures, which is not limited in this embodiment; main bar 2221 and two supporting bars 2222 form a "Y" shape, or two supporting bars 2222 are oppositely arranged to form a "u" shape; one end of each of the two struts 2222 close to the main rod 2221 is selectively connectable (for example, one end is provided with an external thread, the other end is provided with a threaded sleeve with an internal thread, the threaded sleeve is adapted to the external thread to facilitate rotational locking and unlocking, or one end is provided with a buckling part, the other end is provided with a buckling hole, and the two struts 2222 are buckled and connected);

in addition, the bottom of the seat tube 30 is provided with a telescopic walking wheel 70, when the seat tube is used, the walking wheel 70 can be adjusted upwards and does not contact the ground, and when the seat tube is folded and pushed, the walking wheel 70 can be adjusted downwards and contacts the ground; the road wheels 70 may have one or two wheels of different sizes, with or without rotation about the seat tube 30; and the traveling wheels 70 can be directly installed on the seat tube 30 through various installation mechanisms to be telescopic up and down.

The design of the invention is characterized in that:

the faucet comprises a main rod and two supporting rods, wherein one end of the main rod is hinged to a faucet pipe, the two supporting rods are connected to the other end of the main rod and can rotate relative to the main rod, and one end, far away from the main rod, of each supporting rod is connected with a handle; the whole faucet can be adjusted to different angles and heights to adapt to the ergonomics of different people, the supporting rod can be rotated, and the bicycle is more compact and occupies small space when being folded;

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical scope of the present invention, so that any minor modifications, equivalent changes and modifications made to the above embodiment according to the technical spirit of the present invention are within the technical scope of the present invention.

Claims

1. A small and comfortable folding bicycle comprises a main supporting pipe, wherein a single-fork front wheel steering mechanism is arranged at the front end of the main supporting pipe, a seat pipe is arranged at the rear end of the main supporting pipe, a telescopic seat cushion is arranged at the top of the seat pipe and is positioned above the main supporting pipe, a rear wheel steering mechanism is also arranged on the seat pipe and is positioned below the main supporting pipe; the method is characterized in that:

the front wheel section and the rear wheel section of the main supporting pipe are connected through a double-hinge mechanism, so that the front wheel section and the rear wheel section can be folded into a U shape; the double-hinge mechanism is provided with a locking mechanism which can selectively fix the front wheel section and the rear wheel section; the double-hinge mechanism comprises a connecting pipe and two hinges arranged on one side of the connecting pipe, one ends of the two hinges are connected to the connecting pipe, the other ends of the two hinges are connected to the front wheel section and the rear wheel section respectively, the locking mechanism is arranged on the other side of the connecting pipe and comprises two racks and a rotating button meshed between tooth parts of the two racks, and the rotating button drives the racks to move relatively or oppositely to lock the front wheel section and the rear wheel section with rotation.

2. The small and comfortable folding bicycle of claim 1, characterized in that: the single-fork front wheel steering mechanism comprises a head pipe, a handlebar assembly and a front wheel assembly, wherein the handlebar assembly is arranged at the upper end of the head pipe, and the front wheel assembly is arranged at the lower end of the head pipe; the front wheel subassembly is including front wheel mounting bracket and front wheel, the front wheel mounting bracket is horizontal "A" font, the front wheel mounting bracket articulates the suspension stay tube in the one end of front wheel single fork including front wheel single fork and one end, the other end of front wheel single fork is connected in head pipe lower extreme, the front wheel is connected in the other end of suspension stay tube, the other end of suspension stay tube still is provided with the braking system who is used for the brake, press from both sides between front wheel single fork and the suspension stay tube and be equipped with first suspension bumper shock absorber.

3. The small and comfortable folding bicycle of claim 2, wherein: the handlebar assembly comprises a faucet pipe which is telescopically arranged at the upper end of the head pipe and a faucet which is hinged at the upper end of the faucet pipe, the faucet comprises a main rod with one end hinged to the faucet pipe and two supporting rods connected to the other end of the main rod, the two supporting rods can rotate relative to the main rod, and one ends of the supporting rods, far away from the main rod, are connected with a handle.

4. The small and comfortable folding bicycle of claim 3, characterized in that: one end of the two branch rods close to the main rod can be selectively connected.

5. The small and comfortable folding bicycle of claim 1, wherein: the rear wheel steering mechanism comprises a rear wheel installation pipe, the rear wheel installation pipe is arranged on the seat pipe, the rear wheel installation pipe is provided with a bicycle crank component, a rear wheel supporting connecting rod component and a rear wheel, and the bicycle crank component and the rear wheel supporting connecting rod component are respectively located on the front side and the rear side of the seat pipe.

6. The small and comfortable folding bicycle of claim 5, characterized in that: the rear wheel support connecting rod assembly comprises a rear upper fork and a rear lower fork, one end of the rear upper fork is hinged to the seat tube through a second suspension shock absorber, the other end of the rear upper fork is connected with one end of the rear lower fork, the other end of the rear lower fork is hinged to the rear wheel mounting tube, a first support reinforcing piece is clamped between the rear upper fork and the rear lower fork, and the rear wheel is connected to the rear lower fork.

7. The small and comfortable folding bicycle of claim 6, characterized in that: the bicycle crank component comprises a bicycle crank, two foldable pedals connected to the bicycle crank, and a chain connected with the bicycle crank and a rear wheel, and the rear lower fork is further provided with a speed changer for changing speed of the chain.

8. The small and comfortable folding bicycle of claim 6, characterized in that: the front end of rear wheel installation pipe passes through the second and supports the reinforcement and connect the main tributary stay tube, first support reinforcement, second support reinforcement are the fretwork setting.

9. The small and comfortable folding bicycle of claim 1 or 5, wherein: the bottom of the seat tube is provided with a walking wheel which is arranged in a telescopic way.