CN205034258U

CN205034258U - Portable folding bicycle

Info

Publication number: CN205034258U
Application number: CN201520632232.9U
Authority: CN
Inventors: 舒秀山
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-08-21
Filing date: 2015-08-21
Publication date: 2016-02-17
Anticipated expiration: 2025-08-21

Abstract

The utility model relates to a portable folding bicycle, including front wheel subassembly, front fork subassembly, horizontal in subassembly, beam assembly, rear wheel subassembly, rear wheel bracket component, saddle subassembly, the front fork subassembly sets up on the front wheel subassembly, and the rear wheel bracket component sets up on the rear wheel subassembly, is equipped with beam assembly between front fork subassembly and the rear wheel bracket component, and set up horizontal on the front fork subassembly the subassembly, set up the saddle subassembly on the rear wheel bracket component to and including drive and drive assembly, brake subassembly. The utility model discloses a superior effect lies in: overlap with the wheel part with the overlapping of rear wheel part, beam assembly through setting up a plurality of X types shrinks mechanism, front wheel, ultra -thin folding pedal, after folding small, the light in weight of bicycle, easily carry, the front fork riser sets up the edge at the front wheel, increases effective wheel base after the expansion, and the messenger rides safelyr.

Description

A kind of portable folding bicycle

Technical field

The utility model relates to bicycle structure technical field, is specifically related to a kind of portable folding bicycle.

Background technology

In prior art, after the folding mode of bicycle is folding by bicycle, be unfavorable for carrying, particularly riding in a bus or the situation of subway.Along with current economic develop rapidly, city is expanded rapidly, and traffic jam issue is on the rise, and automobile is no longer the best walking-replacing tool of citizens' activities, and portable folding bicycle coordinates with city motor bus or subway to go on a journey will become a kind of new trend.In order to solve bicycle in prior art fold after carry problem, the utility model people of the application proposes a kind of portable folding bicycle according to years of researches experiment.

Utility model content

The purpose of this utility model is to overcome deficiency of the prior art, provides a kind of portable folding bicycle.

The utility model is achieved through the following technical solutions:

A kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; Described front fork assembly is arranged on front component, rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with between front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on rear wheel support assembly, and comprise for driving the driving of front component and/or wheel assembly and transmission component, for braking the brake assemblies of front component and/or wheel assembly.

Described technical scheme is preferably, described front component comprises the front-wheel that two concentrics are arranged, described wheel assembly comprises the trailing wheel that two concentrics are arranged, front-wheel is identical with the diameter of trailing wheel, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than 0 and is less than the diameter of front-wheel or trailing wheel, described front fork assembly comprises the front fork be connected with front-wheel, and is arranged at the vertical tube of front fork on front fork, the bus of vertical tube of front fork and the cylindrical of front-wheel tangent, described cross handle assembly comprises front slip pipe, cross handle standpipe and is fixedly installed on the cross handle body of cross handle standpipe upper end, cross handle standpipe is fixed by fast locking device and front slip pipe, described front slip pipe is fixed by the top of fast locking device and front fork top pipe, and after folding, described front slip pipe is between front component, described rear wheel support assembly comprises rear wheel support, and rear wheel support end is provided with back vent, and back vent is fixedly connected with rear wheel support, described saddle assembly comprises vehicle seat slip pipe, vehicle seat standpipe, vehicle seat body, seat stays plate and storage battery, described vehicle seat slip pipe is fixed by fast locking device and rear wheel support, vehicle seat standpipe is fixed by fast locking device and vehicle seat slip pipe, the top of vehicle seat standpipe is provided with seat stays plate, vehicle seat body is slided and is fixed by contraction type bearing pin and seat stays plate on seat stays plate, and the downside of vehicle seat body is provided with storage battery, described two front-wheels, two trailing wheels are separately positioned on the both sides of transverse beam assembly, described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, the rear portion of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear portion of the 5th pole and the front end of the 6th pole hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, first pole and the second pole adopt the first bearing pin spacing, 5th pole and the 6th pole adopt the second bearing pin spacing, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 4th pole, the rear end of the 6th pole is connected with rear wheel support respectively, described front fork is arranged at inner side or the outside of front-wheel, and described back vent is arranged at inner side or the outside of trailing wheel, described two trailing wheels are arranged between two front-wheels, or two front-wheels are arranged between two trailing wheels.

Described technical scheme is preferably, described transverse beam assembly adopts three X-type contracting mechanisms, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, 7th pole, 8th pole, the rear portion of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and the front end of the 6th pole hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and the front end of the 7th pole hinged, the rear portion of the 7th pole and the front end of the 8th pole hinged, first pole and the second pole adopt the first bearing pin spacing, 7th pole and the 8th pole adopt the second bearing pin spacing, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, 6th pole is flexibly connected by the 3rd pole axle with the 7th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole, the rear end of the 8th pole is connected with rear wheel support respectively.

Described technical scheme is preferably, and described driving and transmission component comprise pedal and drive and driving device and/or electric powerplant; Described pedal drives and comprises folding pedals with driving device, and for transmitting the first order driving device of power that folding pedals produces, first order driving device coordinate with second stage driving device and second stage driving device by transmission of power to the S. A. of trailing wheel; Described electric powerplant comprise the electric machine support being arranged on front fork or back vent place, the motor be arranged on electric machine support, with motor with the use of speed reduction gearing, described motor is connected with storage battery by wire, or described electric powerplant is the motor wheel that in above-mentioned front component or wheel assembly, at least one wheel is set to integrate motor, described brake assemblies comprises for braking the front wheel brake device of front component and the rear-wheel brake equipment for braking rear-wheel assembly, and described brake gear is arranged on the inside of front-wheel and trailing wheel;

Described folding pedals is pin type folding pedals, comprise the stretcher cleat for coordinating with bicycle middle shaft, described stretcher cleat is a hollow frame, the inner side of stretcher cleat is provided with flap axle, flap axle is provided with the flap assembly rotated centered by the axis of flap axle, flap assembly is fixedly connected with step tread plate axle, and be connected with step tread plate axle, the step tread plate that rotates centered by the axis of step tread plate axle.Described flap assembly comprises the flap be connected with flap axle, described flap is T shape, flap is at least provided with one for limiting the bearing pin of flap position, described bearing pin is connected with stage clip, the other end of stage clip is fixed on flap, bearing pin is provided with the joystick being set to one with it, and flap is provided with the guide groove coordinated with joystick, and stretcher cleat is provided with the pin shaft hole coordinated with bearing pin; Described flap axle is vertical with step tread plate axle to be arranged.

Described technical scheme is preferably, described folding pedals adopts pin block formula folding pedals, comprise the stretcher cleat for coordinating with bicycle middle shaft, described stretcher cleat is a hollow frame, the inner side of stretcher cleat is provided with flap axle, flap axle is provided with the flap assembly rotated centered by the axis of flap axle, and flap assembly is fixedly connected with step tread plate axle, and be connected with step tread plate axle, the step tread plate that rotates centered by the axis of step tread plate axle.Described flap assembly comprises the flap be connected with flap axle, described flap is T shape, is at least provided with a chute in flap, is provided with the pin block along the movement of chute direction in described chute, pin block is connected with flap by extension spring, and described stretcher cleat is provided with the position-limited trough for limiting pin block position; Described flap axle is vertical with step tread plate axle to be arranged.

A kind of portable folding bicycle, comprise front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly, described front component comprises the front-wheel that two concentrics are arranged, described wheel assembly comprises the trailing wheel that two concentrics are arranged, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than 0 and is less than the diameter of front-wheel or trailing wheel, described front fork assembly is arranged on front component, described rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with by sliding sleeve and vehicle seat arm between described front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on transverse beam assembly, and comprise for driving the driving of front component and/or wheel assembly and transmission component, for braking the brake assemblies of front component and/or wheel assembly, described two front-wheels, two trailing wheels are separately positioned on the both sides of transverse beam assembly, described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, sliding sleeve, vehicle seat arm, the rear end of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and one end of vehicle seat arm bottom hinged, and the front end of the other end of vehicle seat arm bottom and the 6th pole is hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and one end of sliding sleeve hinged, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole is connected with rear wheel support, the other end of sliding sleeve and the upper end thereof of rear wheel support, described sliding sleeve is fixed by fast locking device and vehicle seat arm, described saddle assembly comprises vehicle seat standpipe, vehicle seat body and storage battery, and described vehicle seat standpipe is fixed by fast locking device and vehicle seat arm, and vehicle seat body and vehicle seat standpipe upper end are fixed, and the downside of vehicle seat body is provided with storage battery, described front fork is arranged at inner side or the outside of front-wheel, and described back vent is arranged at inner side or the outside of trailing wheel, described two trailing wheels are arranged between two front-wheels or two front-wheels are arranged between two trailing wheels.(described front fork assembly, cross handle assembly, rear wheel support assembly, driving and transmission component, brake assemblies identical with the structure in foregoing)

Described technical scheme is preferably, and described transverse beam assembly adopts three X-type contracting mechanisms, comprises the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, 7th pole, 8th pole, sliding sleeve, vehicle seat arm, the rear end of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and one end of vehicle seat arm bottom hinged, and the front end of the other end of vehicle seat arm bottom and the 6th pole is hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and one end of sliding sleeve hinged, and the front end of the other end of sliding sleeve and the 7th pole is hinged, the rear end of the 7th pole and the front end of the 8th pole hinged, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, 6th pole is flexibly connected by the 3rd pole axle with the 7th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole, the rear end of the 8th pole is connected with rear wheel support respectively, and described sliding sleeve is fixed by fast locking device and vehicle seat arm.

Described technological selection is, described two front-wheels are arranged between two trailing wheels, and two front-wheels are arranged on a shaft and two front-wheels are fixedly connected with, and two trailing wheels are arranged on a shaft; The cylindrical of two front-wheels is disposed radially the front-wheel otch that at least one pair of length is less than radius, time folding, makes the axle of trailing wheel be in described front-wheel otch.

Described technological selection is, described front component is provided with a front-wheel, wheel assembly is provided with a trailing wheel, front-wheel and the cylindrical of front-wheel identical with the diameter of trailing wheel is provided with the annular groove for holding trailing wheel, front slip pipe and vehicle seat standpipe, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than the radius of front-wheel or trailing wheel and is less than the diameter of front-wheel or trailing wheel.

Compared with prior art, superior effect of the present utility model is: by arrange some fast locking devices realize folding after the quick release of each spare part, launch after locking; By arranging some X-type contracting mechanisms, allowing transverse beam assembly fold between wheels, and the multiple means such as folding rear ultra-thin folding pedals are set, bicycle length dimension after folding, gauge, height dimension are all greatly reduced, when particularly only arranging electric powerplant, size is less, and lightweight, be more convenient for carrying.Described vertical tube of front fork is arranged on the edge of front-wheel, increases effective wheelbase after deployment, and it is safer to make to ride; By adopting pedal to drive and driving device and/or electric powerplant, improve the alerting ability that folding bicycle power is selected.

Accompanying drawing explanation

The following drawings is only intended to schematically illustrate the utility model and explain, does not limit scope of the present utility model.Wherein:

Fig. 1 is the first example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 2 is the second example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 3 is the 3rd example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 4 is the 4th example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 5 is the 5th example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 6 is the 6th example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 7 is the 7th example structure schematic diagram of portable folding bicycle described in the utility model;

Fig. 8 is the first embodiment front view of the utility model folding pedals;

Fig. 9 is the birds-eye view of folding pedals described in Fig. 8;

Figure 10 is the lateral plan of folding pedals described in Fig. 8;

Figure 11 is the folded state of folding pedals described in Figure 10;

Figure 12 is the second embodiment front view of folding pedals described in the utility model;

Figure 13 is the birds-eye view of folding pedals described in Figure 11;

Figure 14 is the lateral plan of folding pedals described in Figure 11;

Figure 15 is the folded state of folding pedals described in Figure 14.

Accompanying drawing mark is as follows:

11-front-wheel, 111-front-wheel otch, 21-front fork, 22-vertical tube of front fork, slip pipe before 31-, 32-cross handle standpipe, 33-cross handle body, the fast locking device of 34-, 411-first pole, 412-second pole, 413-the 3rd pole, 414-the 4th pole, 415-the 5th pole, 416-the 6th pole, 417-the 7th pole, 418-the 8th pole, 421-first bearing pin, 422-second bearing pin, 431-first pole axle, 432-second pole axle, 433-the 3rd pole axle, 44-sliding sleeve, 45-vehicle seat arm, trailing wheel 51, 61-rear wheel support, 62-back vent, 71-vehicle seat slip pipe, 72-vehicle seat standpipe, 73-vehicle seat body, 74-seat stays plate, 75-storage battery, 81-folding pedals, 82-first order driving device, 83-second stage driving device, 84-electric machine support, 85-motor, 86-speed reduction gearing, 87-motor wheel, 811-stretcher cleat, 812-flap axle, 814-step tread plate axle, 815-step tread plate, 813-flap assembly, 8131-flap, 8132-bearing pin, 8133-stage clip, 8134-joystick, 8135-pin block, 8136-extension spring, 8137-connecting panel, 8161-guide groove, 8162-first pin shaft hole, 8163-scratches hand hole, 8164-position-limited trough, 8165-open recess, 8166-chute, 8167-limiting stopper, 8168-second pin shaft hole, 8169-draw-in groove, 91-front wheel brake device, 92-rear-wheel brake equipment.

Detailed description of the invention

Below in conjunction with accompanying drawing, the utility model detailed description of the invention is described in further detail.

Clear for allowing inside wheel structure show, do not depict some front-wheels and trailing wheel in each accompanying drawing.

Embodiment 1

As shown in Figure 1, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; Described front fork assembly is arranged on front component, rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with between front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on rear wheel support assembly, and comprise for driving the driving of wheel assembly and transmission component, for braking the brake assemblies of front component, wheel assembly.

Described front component comprises the front-wheel 11 that two concentrics are arranged, described wheel assembly comprises the trailing wheel 51 that two concentrics are arranged, front-wheel 11 is identical with the diameter of trailing wheel 51, and the distance of front-wheel 11 and trailing wheel 51 axis of described front-wheel 11 and the axis of trailing wheel 51 is after folding greater than 0 and is less than the radius of front-wheel 11 or trailing wheel 51; Described front fork assembly comprises the front fork 21 be connected with front-wheel 11, and is arranged at the vertical tube of front fork 22 on front fork 21, the bus of vertical tube of front fork 22 and the cylindrical of front-wheel 11 tangent; Described cross handle assembly comprises front slip pipe 31, cross handle standpipe 32 and is fixedly installed on the cross handle body 33 of cross handle standpipe 32 upper end, cross handle standpipe 32 is fixed by fast locking device 34 and front slip pipe 31, described front slip pipe 31 is fixed with the top of front fork 21 top pipe by fast locking device 34, and after folding, described front slip pipe 31 is between front component; Described cross handle body 33 is set to three sections, and cross handle interlude is fixedly connected with cross handle standpipe 32, both sides section releases pin card device post-tensioning, turn, be folded in the both sides of vertical tube of front fork 22 respectively; Described rear wheel support assembly comprises rear wheel support 61, and rear wheel support 61 end is provided with back vent 62, and back vent 62 is fixedly connected with rear wheel support 61; Described saddle assembly comprises vehicle seat slip pipe 71, vehicle seat standpipe 72, vehicle seat body 73, seat stays plate 74 and storage battery 75, described vehicle seat slip pipe 71 is fixed by fast locking device 34 and rear wheel support 61, vehicle seat standpipe 72 is fixed by fast locking device 34 and vehicle seat slip pipe 71, the top of vehicle seat standpipe 72 is provided with seat stays plate 74, vehicle seat body 73 slides and passes through contraction type bearing pin and seat stays plate 74 is fixed on seat stays plate 74, and the downside of vehicle seat body 73 is provided with lithium storage battery 75; Described two front-wheels 11, two trailing wheels 51 are separately positioned on the both sides of transverse beam assembly.

Described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole 411, second pole 412, 3rd pole 413, 4th pole 414, 5th pole 415, 6th pole 416, the rear portion of the first pole 411 and the front end of the second pole 412 hinged, the rear end of the second pole 412 and the front end of the 5th pole 415 hinged, the rear portion of the 5th pole 415 and the front end of the 6th pole 416 hinged, the rear end of the 3rd pole 413 and the front end of the 4th pole 414 hinged, first pole 411 and the second pole 412 adopt the first bearing pin 421 spacing, 5th pole 415 and the 6th pole 416 adopt the second bearing pin 422 spacing, second pole 412 is flexibly connected by the first pole axle 431 with the 3rd pole 413, 4th pole 414 is flexibly connected by the second pole axle 432 with the 5th pole 415, the front end of the first pole 411, the front end of the 3rd pole 413 is connected with vertical tube of front fork 22 respectively, the rear end of the 4th pole 414, the rear end of the 6th pole 416 is connected with rear wheel support 61 respectively.

Described driving and transmission component comprise pedal and drive and driving device and electric powerplant; Described pedal drives and comprises folding pedals 81 with driving device, and for transmitting the first order chain gearing (first order Chain conveyer ratio is greater than 1) of power that folding pedals 81 produces, first order chain gearing coordinates with second stage chain gearing (second stage chain-drive transmitting ratio is greater than 1) and second stage chain gearing by transmission of power to the S. A. of trailing wheel 51; Described electric powerplant is arranged on back vent 62 place, comprise the electric machine support 84 be arranged on back vent 62, and the motor 85 be arranged on electric machine support 84, with motor 85 with the use of speed reduction gearing 86, described speed reduction gearing 86 adopts chain drive, and described motor 85 is connected with lithium ion storage battery 75 by wire; Described brake assemblies comprises the front wheel brake device 91 for braking front component and the rear-wheel brake equipment 92 for braking rear-wheel assembly, and described brake gear is arranged on the inside of front-wheel 11 and trailing wheel 51.

As shown in Fig. 8 ~ 11, described folding pedals 81 is pin type folding pedals 81, comprise the stretcher cleat 811 for coordinating with bicycle middle shaft, described stretcher cleat 811 is a hollow frame, the inner side of stretcher cleat 811 is provided with flap axle 812, flap axle 812 is provided with the flap assembly 813 rotated centered by the axis of flap axle 812, and flap assembly 813 is fixedly connected with step tread plate axle 814, and be connected with step tread plate axle 814, the step tread plate 815 that rotates centered by the axis of step tread plate axle 814.

Described flap assembly 813 comprises the flap 8131 be connected with flap axle 812, described flap 8131 is in T shape, flap 8131 is provided with two for limiting the bearing pin 8132 of flap 8131 position, described bearing pin 8132 is connected with stage clip 8133, and stage clip 8133 is arranged between two bearing pins 8132, each bearing pin 8132 being equipped with one is set to integrally with it, for making the joystick 8134 of bearing pin 8132 movement, described flap 8131 is provided with the guide groove 8161 coordinated with joystick 8134, stretcher cleat 811 is provided with the first pin shaft hole 8162 and the second pin shaft hole 8168 coordinated with bearing pin 8132, first pin shaft hole 8162 coordinates with bearing pin 8132 when launching for flap 8131, limits flap 8131, not exclusively spacing when the second pin shaft hole 8168 folds for flap 8131, described flap axle 812 is vertical with step tread plate axle 814 to be arranged, described stretcher cleat 811 is provided with limiting stopper 8167, and described step tread plate 815 is provided with the draw-in groove 8169 coordinated with described limiting stopper 8167, and step tread plate 815 is provided with open recess 8165.

The method for folding of described folding pedals 81, pinches two joysticks 8134 with two fingers, makes the bearing pin 8132 on flap 8131 depart from spacing; Centered by the axis of flap axle 812, rotate flap assembly 813, when step tread plate 815 and flap 8131 are 0 degree with the angle of stretcher cleat 811 and bearing pin 8132 is located at the second pin shaft hole 8168 of stretcher cleat 811, realize the folding of folding pedals;

After folding pedals 81 is folding, it is inner that flap assembly 813 and step tread plate 815 are folded in stretcher cleat 811, and the size of thickness direction is little.

The inside that described front fork 21 is arranged at the inside of two front-wheels 11, described back vent 62 is arranged at two trailing wheels 51; Described two trailing wheels 51 are arranged between two front-wheels 11, drive and transmission component is arranged between two trailing wheels 51.Front-wheel 11 is inner, thin-wall construction is arranged in trailing wheel 51 inside.

The method for folding of described portable folding bicycle, pack up folding pedals 81, rotating front fork 21 makes front-wheel 11 rotate 180 °, bearing pin is separated with pin shaft hole, unclamps fast locking device, folding transverse beam assembly, transverse beam assembly is made to be folded between front component or wheel assembly, front-wheel 11 is less than radius of wheel with the wheelbase of trailing wheel 51, folding cross handle assembly and saddle assembly.

After car load is folding, front-wheel 11 is less than radius of wheel with the wheelbase of trailing wheel 51, and transverse beam assembly and wheel partly overlap in the height direction, makes full car length, the size of short transverse significantly reduces; Adopt fully folding folding pedals 81, the gauge of car load significantly reduces, if only arrange electric powerplant, then the size of thickness direction can be less.

For increasing traveling comfort and property easy to carry, transverse beam assembly or vertical tube of front fork 22 arranging folding air baffle, folding pedal plate, rear wheel support 61 arrange damping spring, front fork 21 or back vent 62 lower end arrange folding after the caster device of carrying.

Embodiment 2

As shown in Figure 2, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; Wherein, described front component, front fork assembly, cross handle assembly, wheel assembly, rear wheel support assembly, saddle assembly, driving are identical with the structure of transmission component, brake assemblies and above-described embodiment 1.

Described transverse beam assembly adopts three X-type contracting mechanisms, comprise the first pole 411, second pole 412, 3rd pole 413, 4th pole 414, 5th pole 415, 6th pole 416, 7th pole 417, 8th pole 418, the rear portion of the first pole 411 and the front end of the second pole 412 hinged, the rear end of the second pole 412 and the front end of the 5th pole 415 hinged, the rear end of the 5th pole 415 and the front end of the 6th pole 416 hinged, the rear end of the 3rd pole 413 and the front end of the 4th pole 414 hinged, the rear end of the 4th pole 414 and the front end of the 7th pole 417 hinged, the rear portion of the 7th pole 417 and the front end of the 8th pole 418 hinged, first pole 411 and the second pole 412 adopt the first bearing pin 421 spacing, 7th pole 417 and the 8th pole 418 adopt the second bearing pin 422 spacing, second pole 412 is flexibly connected by the first pole axle 431 with the 3rd pole 413, 4th pole 414 is flexibly connected by the second pole axle 432 with the 5th pole 415, 6th pole 416 is flexibly connected by the 3rd pole axle 433 with the 7th pole 417, the front end of the first pole 411, the front end of the 3rd pole 413 is connected with vertical tube of front fork 22 respectively, the rear end of the 6th pole 416, the rear end of the 8th pole 418 is connected with rear wheel support 61 respectively.

As shown in Figure 12 ~ 15, described folding pedals 81 adopts pin block formula folding pedals 81, comprise the stretcher cleat 811 for coordinating with bicycle middle shaft, described stretcher cleat 811 is a hollow frame, the inner side of stretcher cleat 811 is provided with flap axle 812, flap axle 812 is provided with the flap assembly 813 rotated centered by the axis of flap axle 812, and flap assembly 813 is fixedly connected with step tread plate axle 814, and be connected with step tread plate axle 814, the step tread plate 815 that rotates centered by the axis of step tread plate axle 814.

Described flap assembly 813 comprises the flap 8131 be connected with flap axle 812, described flap 8131 is in T shape, flap 8131 both sides are provided with two chutes 8166, be equipped with pin block 8135 along chute 8166 direction movement in each chute 8166 and pin block 8135 is connected with flap 8131 by extension spring 8136, fixed by connecting panel 8137 between two pin blocks 8135; Described stretcher cleat 811 is provided with the position-limited trough 8164 for limiting pin block 8135 position; The end of described pin block 8135 is provided with stingy hand hole 8163; Described flap axle 812 is vertical with step tread plate axle 814 to be arranged; Described stretcher cleat 811 is provided with limiting stopper 8167, and described step tread plate 815 is provided with the draw-in groove 8169 coordinated with described limiting stopper 8167, and described step tread plate 815 is provided with open recess 8165.

The inside that described front fork 21 is arranged at the inside of two front-wheels 11, described back vent 62 is arranged at two trailing wheels 51; Described two trailing wheels 51 are arranged between two front-wheels 11, drive and transmission component is arranged between two trailing wheels 51; Front-wheel is inner, trailing wheel is inner is arranged to thin-wall construction.

After car load is folding, front-wheel 11 is less than radius of wheel with the wheelspan of trailing wheel 51, and transverse beam assembly and wheel partly overlap in the height direction, makes full car length, the size of short transverse significantly reduces; If only arrange electric powerplant, then the size of thickness direction can significantly reduce.

Embodiment 3

As shown in Figure 3, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; Described front fork assembly is arranged on front component, described rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with by sliding sleeve 44 and vehicle seat arm 45 between described front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on transverse beam assembly, and comprise for driving the driving of wheel assembly and transmission component, for braking the brake assemblies of front component and wheel assembly; Described two front-wheels 11, two trailing wheels 51 are separately positioned on the both sides of transverse beam assembly; Described saddle assembly comprises vehicle seat standpipe 72, vehicle seat body 73 and lithium storage battery 75, and described vehicle seat standpipe 72 is fixed with vehicle seat arm by fast locking device 34, and vehicle seat body 73 and vehicle seat standpipe 72 upper end are fixed, and the downside of vehicle seat body 73 is provided with lithium storage battery 75.Described front component, front fork assembly, cross handle assembly, wheel assembly, rear wheel support assembly, drive identical with the structure of transmission component, brake assemblies and above-described embodiment 1.

Described transverse beam assembly adopts three X-type contracting mechanisms, comprise the first pole 411, second pole 412, 3rd pole 413, 4th pole 414, 5th pole 415, 6th pole 416, 7th pole 417, 8th pole 418, sliding sleeve 44, vehicle seat arm 45, the rear end of the first pole 411 and the front end of the second pole 412 hinged, the rear end of the second pole 412 and the front end of the 5th pole 415 hinged, one end of the rear end of the 5th pole 415 and the bottom of vehicle seat arm 45 is hinged, and the front end of the other end of the bottom of vehicle seat arm 45 and the 6th pole 416 is hinged, the rear end of the 3rd pole 413 and the front end of the 4th pole 414 hinged, rear end and the sliding sleeve 44 of the 4th pole 414 are hinged, and the front end of the other end of sliding sleeve 44 and the 7th pole 417 is hinged, the rear end of the 7th pole 417 and the front end of the 8th pole 418 hinged, second pole 412 is flexibly connected by the first pole axle 431 with the 3rd pole 413, 4th pole 414 is flexibly connected by the second pole axle 432 with the 5th pole 415, 6th pole 416 is flexibly connected by the 3rd pole axle 433 with the 7th pole 417, the front end of the first pole 411, the front end of the 3rd pole 413 is connected with vertical tube of front fork 22 respectively, the rear end of the 6th pole 416, the rear end of the 8th pole 418 is connected with rear wheel support 61 respectively, described sliding sleeve 44 is fixed by fast locking device 34 and vehicle seat arm 45.

Described front fork 21 is arranged at the inner side of two front-wheels 11, and described back vent 62 is arranged at the inner side of two trailing wheels 51; Described two trailing wheels 51 are arranged between two front-wheels 11, drive and transmission component is arranged between two trailing wheels 51.

Embodiment 4

As shown in Figure 4, a kind of portable folding bicycle, comprise front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly, driving and transmission component, brake assemblies, wherein, front fork assembly, cross handle assembly, transverse beam assembly, rear wheel support assembly, saddle assembly, brake assemblies are identical with the structure of above-described embodiment 3.

Two front-wheels 11 are arranged between two trailing wheels 51, and front fork 21 is arranged on outside two front-wheels 11, and two front-wheels 11 are arranged on a shaft, two trailing wheels 51 arrange on a shaft, arrange pedal and drive and driving device and electric powerplant.Pedal drives and driving device and front-wheel 11 and front fork 21 are disposed in parallel between the both sides of transverse beam assembly, two trailing wheels 51 on the thickness direction of wheel; Electric powerplant is arranged on back vent 62 place, and motor 85 is arranged between two front-wheels 11, and speed reduction gearing 86 is arranged at the inside of a trailing wheel 51, adopts chain drive.

After car load is folding, front-wheel 11 is greater than radius of wheel with the wheelspan of trailing wheel 51, is less than wheel diameter, and transverse beam assembly and wheel partly overlap in the height direction, and full car length is larger than embodiment 3, and when arranging folding pedals, gauge is less.

Embodiment 5

As shown in Figure 5, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly, driving and transmission component, brake assemblies; Wherein, described front fork assembly, cross handle assembly, transverse beam assembly, rear wheel support assembly, brake assemblies are identical with the structure of above-described embodiment 4.

Described front component comprises two front-wheels 11, described wheel assembly comprises two trailing wheels 51, two front-wheels 11 are between two trailing wheels 51, front fork 21 is inside two front-wheels 11, two front-wheels 11 are fixedly installed on a shaft, and the cylindrical of two front-wheels are disposed radially the front-wheel otch that a pair length is less than radius; Two trailing wheels 51 arrange on a shaft; Electric powerplant is only set in trailing wheel 51 place, and storage battery 75 can be arranged on rear wheel support 61 top.

After folding, the axle of trailing wheel 51 is in described front-wheel otch 111, the wheelspan of front-wheel and trailing wheel is less than radius of wheel, transverse beam assembly and wheel partly overlap in the height direction, and owing to only arranging electric powerplant, make the size of the length of car load, thickness, short transverse all little, be more convenient for carrying.

In addition, trailing wheel also can arrange otch.

Embodiment 6

As shown in Figure 6, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly, driving and transmission component, brake assemblies; Wherein, described front component, front fork assembly, cross handle assembly, rear wheel support assembly, saddle assembly, brake assemblies are identical with the structure of above-described embodiment 5.

Two front-wheels 11 are between two trailing wheels 51, and front fork 21 is inside two front-wheels 11; Only arrange electric powerplant, two trailing wheels 51 in described wheel assembly, one of them trailing wheel 51 is set to the motor wheel 87 of integrated disc type electric machine 85, to form electric powerplant, structure is more succinct; Storage battery 75 can be arranged on rear wheel support 61 top.

Described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole 411, second pole 412, 3rd pole 413, 4th pole 414, 5th pole 415, 6th pole 416, sliding sleeve 44, vehicle seat arm 45, the rear end of the first pole 411 and the front end of the second pole 412 hinged, the rear end of the second pole 412 and the front end of the 5th pole 415 hinged, the rear end of the 5th pole 415 and one end of vehicle seat arm 45 bottom hinged, and the front end of the other end of vehicle seat arm 45 bottom and the 6th pole 416 is hinged, the rear end of the 3rd pole 413 and the front end of the 4th pole 414 hinged, the rear end of the 4th pole 414 and one end of sliding sleeve 44 hinged, second pole 412 is flexibly connected by the first pole axle 431 with the 3rd pole 413, 4th pole 414 is flexibly connected by the second pole axle 432 with the 5th pole 415, the front end of the first pole 411, the front end of the 3rd pole 413 is connected with vertical tube of front fork 22 respectively, the rear end of the 6th pole 416 is connected with rear wheel support 61, the other end of sliding sleeve 44 and the upper end thereof of rear wheel support 61, described sliding sleeve 44 is fixed by fast locking device 34 and vehicle seat arm 45.

Transverse beam assembly adopts two X contraction structure, and compared with employing three X contraction structure, number of components decreases, but wheelbase when car load launches is less, if axis of dilatation distance will be increased, then and corresponding increase accessory size.

After folding, the axle of trailing wheel 51 is in described front-wheel otch 111, and the wheelspan of front-wheel and trailing wheel is less than radius of wheel, transverse beam assembly and wheel partly overlap in the height direction, and owing to only arranging electric powerplant, make the size of the length of car load, thickness, short transverse all little, be easy to carry.

Embodiment 7

As shown in Figure 7, a kind of portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; Wherein, described cross handle assembly, transverse beam assembly, saddle assembly, brake assemblies are identical with the structure of above-described embodiment 6.

Described front component is provided with a front-wheel 11, wheel assembly is provided with a trailing wheel 51, front-wheel 11 and cylindrical of front-wheel 11 identical with the diameter of trailing wheel 51 is provided with the annular groove for holding trailing wheel 51, front slip pipe 31 and vehicle seat standpipe 72, after folding, the distance of the axis of described front-wheel 11 and the axis of trailing wheel 51 is greater than the radius of front-wheel 11 or trailing wheel 51, is less than the diameter of front-wheel 11 or trailing wheel 51 for front-wheel 11 and trailing wheel 51; Pedal drives with driving device and front-wheel 11 and front fork 21 is set up in parallel on the thickness direction of wheel, folding pedals 81 is arranged on outside front-wheel 11, speed reduction gearing 86 is arranged on trailing wheel 51 place.

After car load is folding, front-wheel 11 is greater than radius of wheel with the wheelbase of trailing wheel 51, is less than wheel diameter, and transverse beam assembly and wheel are overlapping little in the height direction, and full car length size, height dimension are comparatively greatly, little when gauge ratio arranges two trailing wheels 51.

The utility model is not limited to above-mentioned embodiment, and when not deviating from flesh and blood of the present utility model, any distortion that it may occur to persons skilled in the art that, improvement, replacement all fall into scope of the present utility model.

Claims

1. a portable folding bicycle, comprises front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly; It is characterized in that, described front fork assembly is arranged on front component, rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with between front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on rear wheel support assembly, and comprise for driving the driving of front component and/or wheel assembly and transmission component, for braking the brake assemblies of front component and/or wheel assembly.

2. portable folding bicycle according to claim 1, it is characterized in that, described front component comprises the front-wheel that two concentrics are arranged, described wheel assembly comprises the trailing wheel that two concentrics are arranged, front-wheel is identical with the diameter of trailing wheel, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than 0 and is less than the diameter of front-wheel or trailing wheel, described front fork assembly comprises the front fork be connected with front-wheel, and is arranged at the vertical tube of front fork on front fork, the bus of vertical tube of front fork and the cylindrical of front-wheel tangent, described cross handle assembly comprises front slip pipe, cross handle standpipe and is fixedly installed on the cross handle body of cross handle standpipe upper end, cross handle standpipe is fixed by fast locking device and front slip pipe, described front slip pipe is fixed by the top of fast locking device and front fork top pipe, and after folding, described front slip pipe is between front component, described rear wheel support assembly comprises rear wheel support, and rear wheel support end is provided with back vent, and back vent is fixedly connected with rear wheel support, described saddle assembly comprises vehicle seat slip pipe, vehicle seat standpipe, vehicle seat body, seat stays plate and storage battery, described vehicle seat slip pipe is fixed by fast locking device and rear wheel support, vehicle seat standpipe is fixed by fast locking device and vehicle seat slip pipe, the top of vehicle seat standpipe is provided with seat stays plate, vehicle seat body is slided and is fixed by contraction type bearing pin and seat stays plate on seat stays plate, and the downside of vehicle seat body is provided with storage battery, described two front-wheels, two trailing wheels are separately positioned on the both sides of transverse beam assembly, described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, the rear portion of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear portion of the 5th pole and the front end of the 6th pole hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, first pole and the second pole adopt the first bearing pin spacing, 5th pole and the 6th pole adopt the second bearing pin spacing, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 4th pole, the rear end of the 6th pole is connected with rear wheel support respectively, described front fork is arranged at inner side or the outside of front-wheel, and described back vent is arranged at inner side or the outside of trailing wheel, described two trailing wheels are arranged between two front-wheels or two front-wheels are arranged between two trailing wheels.

3. portable folding bicycle according to claim 2, it is characterized in that, described transverse beam assembly adopts three X-type contracting mechanisms, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, 7th pole, 8th pole, the rear portion of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and the front end of the 6th pole hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and the front end of the 7th pole hinged, the rear portion of the 7th pole and the front end of the 8th pole hinged, first pole and the second pole adopt the first bearing pin spacing, 7th pole and the 8th pole adopt the second bearing pin spacing, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, 6th pole is flexibly connected by the 3rd pole axle with the 7th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole, the rear end of the 8th pole is connected with rear wheel support respectively.

4. portable folding bicycle according to claim 1, is characterized in that, described driving and transmission component comprise pedal and drive and driving device and/or electric powerplant; Described pedal drives and comprises folding pedals with driving device, and for transmitting the first order driving device of power that folding pedals produces, first order driving device coordinate with second stage driving device and second stage driving device by transmission of power to the S. A. of trailing wheel; Described electric powerplant comprise the electric machine support be arranged on front fork or back vent, the motor be arranged on electric machine support, with motor with the use of speed reduction gearing, described motor is connected with storage battery by wire, or described electric powerplant is the motor wheel that in above-mentioned front component or wheel assembly, at least one wheel is set to integrate motor; Described brake assemblies comprises for braking the front wheel brake device of front component and the rear-wheel brake equipment for braking rear-wheel assembly, and described brake gear is arranged on the inside of front-wheel and trailing wheel;

Described folding pedals is pin type folding pedals, comprise the stretcher cleat for coordinating with bicycle middle shaft, described stretcher cleat is a hollow frame, the inner side of stretcher cleat is provided with flap axle, flap axle is provided with the flap assembly rotated centered by the axis of flap axle, flap assembly is fixedly connected with step tread plate axle, and be connected with step tread plate axle, the step tread plate that rotates centered by the axis of step tread plate axle; Described flap assembly comprises the flap be connected with flap axle, described flap is T shape, flap is at least provided with one for limiting the bearing pin of flap position, described bearing pin is connected with stage clip, the other end of stage clip is fixed on flap, bearing pin is provided with the joystick being set to one with it, and flap is provided with the guide groove coordinated with joystick, and stretcher cleat is provided with the pin shaft hole coordinated with bearing pin; Described flap axle is vertical with step tread plate axle to be arranged.

5. portable folding bicycle according to claim 4, it is characterized in that, described folding pedals adopts pin block formula folding pedals, comprise the stretcher cleat for coordinating with bicycle middle shaft, described stretcher cleat is a hollow frame, and the inner side of stretcher cleat is provided with flap axle, and flap axle is provided with the flap assembly rotated centered by the axis of flap axle, flap assembly is fixedly connected with step tread plate axle, and be connected with step tread plate axle, the step tread plate that rotates centered by the axis of step tread plate axle; Described flap assembly comprises the flap be connected with flap axle, described flap is T shape, is at least provided with a chute in flap, is provided with the pin block along the movement of chute direction in described chute, pin block is connected with flap by extension spring, and described stretcher cleat is provided with the position-limited trough for limiting pin block position; Described flap axle is vertical with step tread plate axle to be arranged.

6. a portable folding bicycle, comprise front component, front fork assembly, cross handle assembly, transverse beam assembly, wheel assembly, rear wheel support assembly, saddle assembly, it is characterized in that, described front component comprises the front-wheel that two concentrics are arranged, described wheel assembly comprises the trailing wheel that two concentrics are arranged, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than 0 and is less than the diameter of front-wheel or trailing wheel, described front fork assembly is arranged on front component, described rear wheel support assembly is arranged on wheel assembly, transverse beam assembly is provided with by sliding sleeve and vehicle seat arm between described front fork assembly and rear wheel support assembly, and be arranged at the cross handle assembly on front fork assembly, the saddle assembly be arranged on transverse beam assembly, and comprise for driving the driving of front component and/or wheel assembly and transmission component, for braking the brake assemblies of front component and/or wheel assembly, described two front-wheels, two trailing wheels are separately positioned on the both sides of transverse beam assembly, described transverse beam assembly adopts double X-type contracting mechanism, comprise the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, sliding sleeve, vehicle seat arm, the rear end of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and one end of vehicle seat arm bottom hinged, and the front end of the other end of vehicle seat arm bottom and the 6th pole is hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and one end of sliding sleeve hinged, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole is connected with rear wheel support, the other end of sliding sleeve and the upper end thereof of rear wheel support, described sliding sleeve is fixed by fast locking device and vehicle seat arm, described saddle assembly comprises vehicle seat standpipe, vehicle seat body and storage battery, and described vehicle seat standpipe is fixed by fast locking device and vehicle seat arm, and vehicle seat body and vehicle seat standpipe upper end are fixed, and the downside of vehicle seat body is provided with storage battery, front fork is arranged at inner side or the outside of front-wheel, and back vent is arranged at inner side or the outside of trailing wheel, described two trailing wheels are arranged between two front-wheels, or two front-wheels are arranged between two trailing wheels.

7. portable folding bicycle according to claim 6, is characterized in that, described transverse beam assembly adopts three X-type contracting mechanisms, comprises the first pole, second pole, 3rd pole, 4th pole, 5th pole, 6th pole, 7th pole, 8th pole, sliding sleeve, vehicle seat arm, the rear end of the first pole and the front end of the second pole hinged, the rear end of the second pole and the front end of the 5th pole hinged, the rear end of the 5th pole and one end of vehicle seat arm bottom hinged, and the front end of the other end of vehicle seat arm bottom and the 6th pole is hinged, the rear end of the 3rd pole and the front end of the 4th pole hinged, the rear end of the 4th pole and one end of sliding sleeve hinged, and the front end of the other end of sliding sleeve and the 7th pole is hinged, the rear end of the 7th pole and the front end of the 8th pole hinged, second pole is flexibly connected by the first pole axle with the 3rd pole, 4th pole is flexibly connected by the second pole axle with the 5th pole, 6th pole is flexibly connected by the 3rd pole axle with the 7th pole, the front end of the first pole, the front end of the 3rd pole is connected with vertical tube of front fork respectively, the rear end of the 6th pole, the rear end of the 8th pole is connected with rear wheel support respectively, and described sliding sleeve is fixed by fast locking device and vehicle seat arm.

8. the portable folding bicycle according to claim 2 or 6, is characterized in that, described two front-wheels are arranged between two trailing wheels, and two front-wheels are arranged on a shaft and two front-wheels are fixedly connected with, and two trailing wheels are arranged on a shaft; The cylindrical of two front-wheels is disposed radially the front-wheel otch that at least one pair of length is less than radius, time folding, makes the axle of trailing wheel be in described front-wheel otch.

9. portable folding bicycle according to claim 6, it is characterized in that, described front component is provided with a front-wheel, wheel assembly is provided with a trailing wheel, front-wheel and the cylindrical of front-wheel identical with the diameter of trailing wheel is provided with the annular groove for holding trailing wheel, front slip pipe and vehicle seat standpipe, and the distance of front-wheel and the trailing wheel axis of described front-wheel and the axis of trailing wheel is after folding greater than the radius of front-wheel or trailing wheel and is less than the diameter of front-wheel or trailing wheel.