CN1158807A - Front wheel driven bicycle with gearing - Google Patents

Abstract

The chain-less bicycle has driving cranks fixed at two ends of front wheel shaft and gearing system inside front wheel shaft casing. It is similar to common chain bicycles in the walking distance each time of pedalling and the driving force. It has a front wheel diameter of 56 cm, a back wheel diameter of 35cm, a minimal pedal-to-ground distance of 10 cm, a total length of 100 cm and a seater height of 70cm.

Description

Gear-driven front wheel drive type bicycle

The present invention relates to a kind of chain that do not have, only by gear-driven front wheel drive type bicycle.

It is preceding that the axle mounting crank throw---the bicycle that foot-operated driving is turned once occurred in history, the double simultaneously crank throw of the front wheel spindle of this car turns axle and fixed with each other, front-wheel, front axle and crank throw are synchronous during rotation, this bicycle driving efficient---crank throw is pedaled all pairing garages distance by the people and is directly proportional with wheel diameter, so for practicality, keep more suitable drive efficiency, the car front-wheel is always done very greatly, so just, it is corresponding very high to have influence on vehicle seat, finally is directed at the chain-type back-wheel drive type bicycle that this car occurred afterwards and eliminates.

What people generally used at present is exactly this rear wheel drive bicycle by chain gear, the crank shaft of this car is independent of former and later two wheel shafts, be in the middle part of bicycle, drive efficiency is whenever being pedaled between 4.5～5.5 meters of all garages, drive ratio (ratio of the resistance that propulsive effort that is subjected on the stretcher when car at the uniform velocity travels and car are subjected to) is between 4.5: 1～5.5: 1, such drive efficiency and drive ratio had both guaranteed the moderate speed of a motor vehicle, made the cyclist can not feel to require great effort very much again.When the bicycle driving ratio remained unchanged, drive efficiency was directly proportional with the length of body of crank, and the extreme length of body of crank is subjected to the restriction of organization of human body, thus generally all be selected between 16～17cm, short then drive efficiency is low, long then awkward when pedaling.Just because of body of crank should not shorten, in order to adapt to the position of this situation and former and later two wheels, the seat that is directed at ordinary bicycle is high can't to fall too lowly, generally all about 90cm.So high vehicle seat makes the people be not easy to be sitting in seat and upward supports the road surface simultaneously with both legs, has influence on the safety of bicycle.The length of this in addition chain-type back-wheel drive bicycle will be subjected to the restriction of front and back wheel and three factors of body of crank.

The objective of the invention is improvement by bicycle transmission system, under bicycle drive efficiency and drive ratio and the cooresponding prerequisite of ordinary bicycle, reduce height (seat is high), the length of bicycle, for people provide a kind of simple in structure, ride with flexibly, safely, remove and take bicycle easily.

This bicycle adopts the f-w-d mode, except that the prerequisite front and back wheel of bicycle, front fork, handlebar, frame, seat, unique distinction is that it has a gear-driven f-w-d system, this drive system comprises crank throw, front axle, gear cluster and axle skin, gear cluster comprises first gear, second gear and the 3rd gear, in three transmission gears one is actual to be a kind of distortion of bicycle freewheel, therefore has flywheel functions, is called the tooth flywheel.The tooth flywheel comprises driving wheel, very heavy of flower wheel and in-to-in, spring, antifriction ball.The driving wheel inwall has sawtooth projection, and a certain direction of driving wheel is rotated, and can drive flower wheel because of sawtooth projection hooks very heavy, and for rotating in contrast to this, sawtooth projection can not hook very heavy, so flower wheel can not rotate with driving wheel.Therefore the effect of this tooth flywheel is can effectively rotation and power be passed to wheel when making the crank throw forward rotation, and the rotation of wheel can not passed through the gear set drive crank throw conversely.The axle skin is the middle body of wheel, and it and wheel can be incorporate, also can link to each other with foreign steamer by the wheel bar, and spool leather sheath and is equipped with bearing between them on front axle---the antifriction parts.Crank throw is exactly that the pin road of bicycle drives and to turn, and its end has pin road plate, and the other end is fixed on preceding shaft end, and two crank throws are the center with the front axle, and symmetry is installed.Bicycle front fork is preceding shaft support, it is again the pedestal of second gear, second gear also is driven gear, its axle is the bossing on the preceding half arm again, because it and front axle decentraction can't be passed wheel, therefore second gear is that the axle of driven gear is a stabilizing stand with the front fork half arm only, two arms of front fork and front axle pass through bearing installation together, and bearing is in order to antifriction.Front axle is not only the axle center of wheel and crank throw, first gear and the 3rd gear are the center with it also, first gear also is driving gear, it and front axle fix, or directly link to each other with part that crank throw is fixed on the front axle, skin-deep the fixing of the axle of the 3rd gear and front-wheel also can be made of one with the axle skin, first gear is meshed with second gear, second gear is (by other gear) and the 3rd meshed transmission gear directly or indirectly, the transmission order of driving system is: crank throw is driven by manpower and drives first gear when rotating, through the transmission of second gear and the 3rd gear, drive front-wheel and rotate.

This bicycle driving is than remaining between 4.5: 1～5.5: 1 by the suitable selection of gear cluster.After drive ratio is fixing, be proportional to the principle of drive efficiency according to body of crank length, select maximum crank throw brachium 17.5cm (by the organization of human body decision), the stretcher ground height is elected 10cm as, and this sample car front-wheel radius minimum is 27.5cm.The length of this bicycle is decided by the size of two wheels, and trailing wheel only plays the effect of support wheel here, therefore can design forr a short time.Dwindling of front and back wheel is directed at vehicle seat behind the position that adapts to pin road plate, and the aspect ratio ordinary bicycle can reduce by 10～20cm.

Because this bicycle adopts gear-driven f-w-d mode, kept and cooresponding drive ratio of ordinary bicycle and drive efficiency, and dwindled front and back wheel footpath, to have reduced seat high, shortened the vehicle commander, simplified complete vehicle structure, so its alerting ability, safety, can remove the property taken and all be better than chain-type back-wheel drive bicycle.

Below in conjunction with example and accompanying drawing the present invention is described in further detail:

Fig. 1: gear-driven front wheel drive type bicycle complete vehicle structure.

Fig. 2: running part three-dimensional cutaway view.

Fig. 3: running part section plan.

Fig. 4: tooth flywheel part-structure schematic diagram.

Fig. 5: the graph of a relation of bicycle and human body.

Fig. 6: unfold conceptual scheme.

Gear-driven as described in Figure 1 front wheel drive type bicycle is made up of front-wheel a, trailing wheel b, front fork c, handlebar d, vehicle frame e, vehicle seat f, the foot-operated gear transmission part group j that drives crank throw g, axle skin h and be enclosed in an intracutaneous.

Mainly be made up of crank throw 1, front axle 2, gear 3, gear 4, tooth flywheel 5 and axle skin 6 as the described driving system of Fig. 2, Fig. 3, the tooth flywheel comprises overcoat 5-1, driving wheel 5-2, flower wheel 5-3.Be evenly distributed with spoke hole 12 on the axle skin two outer circumference, axle skin 6 is enclosed within on the front axle 2, be provided with bearing 7 between them---the antifriction parts, the front fork 8 of bicycle be the support of front axle 2 be again the pedestal of gear 4, be provided with the bearing 9 that is used for antifriction between front fork both arms and front axle, gear 4 is sleeved on the protruding super axle 11 of front fork half arm by internal bearings 10.Two crank throws are the axle center with front axle 2, are fixed on front axle 2 both ends symmetrically.Gear 3 is the axle center with front axle 2 also with tooth flywheel 5, and gear 3 is fixed on the front axle 2, and the flower wheel 5-3 of tooth flywheel 5 is buckled on the axial projection 13 of a skin 7 by screw collar.Gear 3 is meshed with the thin end tooth wheel of gear 4, the thin end engagement of the overcoat 5-1 of the butt end of gear 4 and tooth flywheel.

Fig. 4 is described to be the part that the tooth flywheel does not comprise overcoat 5-1, and it is actually the improvement after the bicycle freewheel removes outer tooth, and band is the screw thread of outside face for outer tooth, is used for the screw-internal thread fit socket with overcoat 5-1.Except that driving wheel 5-2, flower wheel 5-3, it also comprises very heavy 5-4, antifriction ball 5-5 and outer catch 5-6.The a plurality of sawtooth projection 5-7 of rectangular distribution on the driving wheel 5-2 inwall circumference, the end of very heavy 5-4 stretches in the recessed poor 5-8 of flower wheel 5-3 outside face, and the other end is by the spring 5-9 jack-up in the recessed poor 5-8.Driving wheel 5-2 in the rotation of a certain direction, can make sawtooth projection 5-7 hook very heavy 5-4, and drive flower wheel 5-3 and rotate synchronously.And driving wheel 5-2 can not make sawtooth projection 5-7 hook very heavy 5-4 to the rightabout rotation of flower wheel 5-3, so flower wheel 5-3 can not rotate with driving wheel 5-2 in such cases, they are not influence mutually.

The existence of tooth flywheel 5 can be effectively when making crank throw 1 forward drive will be rotated and power pass to front-wheel a by gear cluster, and the forward direction of wheel rotates can not drive conversely and sails gear cluster and crank throw 1 is followed wheel.

The working process of this example driving system is as follows: drive front axle 2 and gear 3 rotations when crank throw 1 is just changeing under the manpower effect, gear 3 driven gears 4, gear 4 drive tooth flywheels 5, thereby drive front-wheel a rotation by axle skin 6.Because the existence of tooth flywheel 5, during bicycle running, if crank throw 1 is slack, the rotation of front-wheel a will can not be driven and be sailed gear cluster and crank throw 1 rotation.

In this example, front vehicle wheel a diameter is elected 56cm as, and crank throw 1 brachium is elected 16.5cm as, and trailing wheel b diameter is 35cm, and the long 100cm of vehicle body designs vehicle seat according to the people of 1.65 meters～1.70 meters of heights, the high 70cm that is decided to be of seat, and handlebar is 105～110cm apart from the ground height.

Fig. 6 is second kind of body structure scheme of gear-driven front wheel drive type bicycle, this scheme is a kind of folding scheme, this car can also design according to the mode of baggage car in addition, but which kind of scheme no matter, all benefits from the characteristics of gear-driven front wheel drive type bicycle " little ".

Claims (4)

1, a kind of by gear-driven front wheel drive type bicycle, it comprises the f-w-d system of front-wheel, trailing wheel, front fork, handlebar, vehicle frame, vehicle seat and set of gears transmission, it is characterized in that, this drive system comprises crank throw, front axle, gear cluster and axle skin, some gears in the gear cluster are the tooth flywheels, it has flywheel functions, driving gear in the gear cluster is the center with the front axle, front axle also is the center shaft of car front-wheel, crank throw is fixed on preceding shaft end, front axle is bracing frame with the front fork, and the axle of driven gear is a stabilizing stand with the front fork half arm.

2, as claim 1 said gear cluster, it is characterized in that gear cluster is made of first gear and second gear mesh, second gear and the 3rd gear mesh first gear, second gear and the 3rd gear, first gear is fixed on the front axle, the 3rd gear with the axle skin-deep binding or with axle skin one.

3, it is characterized in that as 1 said skin of claim a skin is in wheel central authorities and links to each other with wheel with the wheel one or by the wheel bar, it is enclosed within on the front axle, and the one side is a cirque structure, and gear cluster is enclosed in the annulus.

4,, it is characterized in that being provided with between front fork and front axle bearing or antifriction parts as claim 1 said front fork.

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