CN205998081U - Bicycle - Google Patents

Abstract

The utility model discloses a kind of bicycle, belongs to walking-replacing tool technical field, which includes drive mechanism, front-wheel, trailing wheel, handle, handlebar stem, cushion.Drive mechanism includes the open Chain conveyer that the closure Chain conveyer formed by fixed mount, first rotating shaft, the second rotating shaft, sprocket wheel, the first flywheel, chain is formed by the second flywheel, the 3rd flywheel, pulley, directive wheel, transmission rope, and transmission rope is pulled by foot reciprocating motion, and drive the second flywheel or the 3rd flywheel to drive first rotating shaft, then the first flywheel is transferred the motion to by sprocket wheel, so as to rear wheel is driven, moving ahead for bicycle is realized.The beneficial effects of the utility model are to improve the utilization ratio that human body is had an effect, and make to ride more laborsaving.

Description

bicycle

technical field

The utility model relates to the technical field of walking tools, in particular to a bicycle.

Background technique

Bicycles are widely used in daily travel. They are flexible, clean and environmentally friendly, and can also exercise. In the existing bicycles, the pedals rotate 360 degrees, and most of the force generated by the human body acts on the axial direction of the crank, and only a small part of the force forms a moment to make the crank rotate. Therefore, there is an efficiency in the utilization of human body force Low, the disadvantage of strenuous effort to pedal a bicycle.

Utility model content

The utility model aims to provide a bicycle to improve the problems of low utilization efficiency of the human body exerting force and laborious pedaling of the bicycle in the prior art.

Embodiments of the utility model are achieved in that:

A bicycle, which includes a transmission structure, and also includes a front wheel, a rear wheel, a handle, a handle bar and a seat cushion.

The transmission structure includes a fixed frame, a first rotating shaft, a second rotating shaft, a sprocket, a first flywheel and a chain.

The first rotating shaft and the second rotating shaft are respectively rotatably connected to the fixed frame, and the first rotating shaft is parallel to the second rotating shaft.

The sprocket is connected to the first rotating shaft, and the first flywheel is connected to the second rotating shaft; the first flywheel is connected to the sprocket through a chain transmission.

The rear wheel is rotatably connected to the second rotating shaft.

The transmission structure also includes a second flywheel, a third flywheel, a pulley, a guide wheel and a transmission rope.

The second flywheel and the third flywheel are connected to the first rotating shaft at a distance from each other, and the second flywheel and the third flywheel are located on the same side of the sprocket wheel.

The fixed frame is connected with a first bracket, the pulley is hinged on the first bracket, and the axis direction of the pulley is perpendicular to the axis direction of the first rotating shaft.

The first bracket includes a guide sleeve and a hinge, the guide sleeve is fixedly connected to the fixed frame, the guide sleeve has a guide hole; the pulley is hingedly connected to one end of the hinge, the other end of the hinge is provided with a guide pin, the bottom surface of the guide pin and the guide hole There are springs between them.

The transmission structure also includes a first pedal, a second pedal, a third pedal and a fourth pedal; a first connecting rod, a second connecting rod, a third connecting rod and a fourth connecting rod; a first connecting part and a second connecting part.

The first connecting part and the second connecting part are respectively rotatably connected to two sides of the second bracket.

The first connecting rod and the third connecting rod are respectively connected to the two ends of the first connecting part, and the first connecting rod and the third connecting rod are collinear, and the first connecting part is rotatably connected to the second bracket; The four connecting rods are respectively connected to two ends of the second connecting part, and the second connecting rod and the fourth connecting rod are collinear, and the second connecting part is rotatably connected to the second bracket.

The drive rope includes a first end, a second end, and a first steel wire segment, a first chain segment, a second steel wire segment and a second chain segment sequentially connected between the first end and the second end.

The first steel wire section corresponds to the guide wheel, the first chain section corresponds to the third flywheel, the second steel wire section corresponds to the pulley, and the second chain section corresponds to the second flywheel.

The first end of the transmission rope is connected to the middle position in the length direction of the second connecting rod, and the second end of the transmission rope goes around the guide wheel, the third flywheel, the pulley, the second flywheel and is connected to the third connecting rod in turn.

After the first pedal is stepped down, the third connecting rod rotates upwards, driving the second end of the transmission rope to rise, and the transmission rope pulls the second flywheel to rotate forward, the second flywheel drives the first rotating shaft to rotate, and the first rotating shaft drives the sprocket to rotate , the third flywheel reverses under the driving of the transmission rope, the transmission rope pulls down the second connecting rod through the guide wheel, the second pedal descends, and the fourth pedal rises.

further:

The fixing frame includes a horizontal section and an inclined section extending from the left end of the horizontal section in an obliquely upward direction.

The first rotating shaft is rotatably connected to the horizontal section near its left end, and the second rotating shaft is rotatably connected to the horizontal section near its right end.

The first support is connected to the junction of the horizontal section and the inclined section, and the pulley is located on the left side of the first support.

The second bracket is connected to the inclined section.

further:

The first rotating shaft and the second rotating shaft are respectively rotatably connected to the fixed frame through bearings.

further:

The second flywheel and the third flywheel are single-stage flywheels, and the single-stage flywheel includes a jacket, flywheel internal teeth, a jack and a core, the jacket is provided with external teeth, and the core is fixedly connected with the second rotating shaft.

further:

The pulley is provided with an annular chute in the circumferential direction, and the second steel wire segment fits in the annular chute.

further:

An annular friction belt is arranged in the annular chute, and the second steel wire section fits on the surface of the friction belt.

further:

The second flywheel and the third flywheel are arranged symmetrically on both sides of the fixing frame.

further:

The length of the first steel wire section is greater than the contact length of the transmission rope and the guide wheel; the length of the first chain section is greater than the contact length of the transmission rope and the third flywheel; the length of the second steel wire section is greater than the contact length of the transmission rope and the pulley; the second The length of the chain segment is greater than the contact length between the transmission rope and the second flywheel.

further:

The second flywheel is the same size as the third flywheel.

further:

The handle is connected to the fixed frame through the handle bar, and the front wheel is rotatably connected to one end of the handle bar.

The seat cushion is fixedly connected to the fixing frame through a rod.

The beneficial effects of the utility model embodiment are:

By setting the second flywheel and the third flywheel on both sides of the sprocket wheel of the first rotating shaft, and then setting the pedals on the fixed frame and the second bracket, the pedals are connected to the connecting rod and rotated to set, when the first pedal and the third pedal Reciprocate up and down, pull the transmission rope through the first connecting rod and the third connecting rod, driven by the driving rope, the second flywheel and the third flywheel rotate at a certain angle in turn to drive the sprocket to rotate, and then drive the rear wheel through the sprocket. Rear wheel drive vehicle movement. Similarly, the forward movement of the bicycle can be realized by stepping on the second pedal and the fourth pedal back and forth, and the human body can choose to use the bicycle in two ways: the left foot is in front, the right foot is behind, or the left foot is behind, and the right foot is in front. Users who can adapt to different habits and requirements. The bicycle exerts force up and down, which improves the problems of low utilization efficiency of the human body's exertion force and strenuous pedaling of the existing bicycle, and riding the bicycle also has the advantages of energy saving, environmental protection and fitness. In addition, since the bicycle needs to overcome resistances such as the static friction between the front and rear wheels and the ground when starting, the human body needs to apply a large force to start the bicycle, which has the disadvantage of laborious starting. , elastically connected to the fixed frame, when starting, the radial force applied to the pulley after the transmission rope is pulled can compress the spring in an appropriate amount, so that the pulley moves a certain distance to the fixed frame, so that the transmission rope can be easily pulled Therefore, the bicycle in the embodiment of the utility model has the beneficial effect of starting with less effort.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following drawings will be briefly introduced in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention. Therefore, it should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained according to these drawings without creative work.

Fig. 1 is a schematic structural view of the bicycle in this embodiment.

Fig. 2 is a structural schematic diagram of the transmission structure in this embodiment.

Fig. 3 is a view from direction A of Fig. 2 (partial structures are not shown).

Fig. 4 is a structural schematic diagram of the connection structure between the pulley and the first bracket in this embodiment.

Fig. 5 is a schematic structural diagram of the pulley in this embodiment.

Fig. 6 is a schematic diagram of the connection structure of the first pedal, the second pedal, the third pedal, the fourth pedal and the fixing frame in this embodiment.

Fig. 7 is a schematic diagram of the cooperative relationship between the transmission rope, the guide wheel, the third flywheel, the pulley and the second flywheel in this embodiment.

Fig. 8 is a schematic structural diagram of the second flywheel and the third flywheel in this embodiment.

Icon: 100-transmission structure; 101-fixed frame; 102-first shaft; 103-second shaft; 104-sprocket; 105-first flywheel; 106-chain; 107-second flywheel; 108-third flywheel ; 111-the first pedal; 112-the second pedal; 113-the third pedal; 114-guide pin; 114-the fourth pedal; 115-spring; 122-the second connecting rod; 123-the third connecting rod; 124-the fourth connecting rod; 125-annular chute; 126-friction belt; 127-horizontal section; Guide sleeve; 132-hinge piece; 133-guide hole; 134-guide pin; 141-second bracket; 151-first connecting part; 152-second connecting part; 210-drive rope; 211-first end; 212 -Second end; 213-first steel wire segment; 214-first chain segment; 215-second steel wire segment; 216-second chain segment; 301-overcoat; 302-flywheel internal teeth; 600-bicycle; 601-front wheel; 602-rear wheel; 603-handle; 604-handle bar; 605-seat cushion.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the utility model more clear, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the utility model. Obviously, the described The embodiments are some embodiments of the present utility model, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present utility model, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", " The orientation or positional relationship indicated by "outside" is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the product of the utility model is used. It is only for the convenience of describing the utility model and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the present invention. In addition, if the terms "first" and "second" appear in the description of the present utility model, they are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

In addition, if terms such as "horizontal" and "vertical" appear in the description of the present utility model, it does not mean that the components are required to be absolutely horizontal or hang, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", and it does not mean that the structure must be completely horizontal, but can be slightly inclined.

In the description of the present utility model, it should also be noted that, unless otherwise specified and limited, if the terms "setting", "installation", "connection" and "connection" appear, they should be understood in a broad sense, for example, it can be A fixed connection can also be a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model in specific situations.

Example

FIG. 1 is a schematic structural view of a bicycle 600 in this embodiment. Please refer to FIG. 1 , the present embodiment provides a bicycle 600 , which includes a transmission structure 100 , a front wheel 601 , a rear wheel 602 , a handle 603 , a rod of the handle 603 and a seat cushion 605 .

FIG. 2 is a schematic structural diagram of the transmission structure 100 in FIG. 1 . Fig. 3 is a view from direction A of Fig. 2 (partial structures are not shown). Please refer to FIG. 2 and FIG. 3 , the transmission structure 100 includes a fixed frame 101 , a first shaft 102 , a second shaft 103 , a sprocket 104 , a first flywheel 105 , and a chain 106 . The first rotating shaft 102 and the second rotating shaft 103 are respectively rotatably connected to the fixing frame 101 , and the first rotating shaft 102 is parallel to the second rotating shaft 103 . The sprocket 104 is connected to the first rotating shaft 102 , and the first flywheel 105 is connected to the second rotating shaft 103 ; the first flywheel 105 is connected to the sprocket 104 through a chain 106 . The rear wheel 602 is rotatably connected to the second shaft 103 . In this embodiment, the first rotating shaft 102 and the second rotating shaft 103 are respectively rotatably connected to the fixing frame 101 through bearings. Please refer to FIG. 1 , the handle 603 is connected to the fixed frame 101 through the handle 603 rod, and the front wheel 601 is rotatably connected to one end of the handle 603 rod. The seat cushion 605 is fixedly connected to the fixing frame 101 through a rod.

Please continue to refer to FIG. 2 and FIG. 3 , the transmission structure 100 also includes a second flywheel 107 , a third flywheel 108 , a pulley 118 , a guide wheel 119 , and a transmission rope 210 . The second flywheel 107 and the third flywheel 108 are connected to the first rotating shaft 102 at intervals, and the second flywheel 107 and the third flywheel 108 are located on the same side of the sprocket 104, and in this embodiment, the second flywheel 107 and the first flywheel 108 The three flywheels 108 have the same size and are symmetrically arranged on both sides of the fixing frame 101 . The fixed frame 101 is connected with a first bracket 130 , the pulley 118 is hinged on the first bracket 130 , and the axis direction of the pulley 118 is perpendicular to the axis direction of the first rotating shaft 102 . The first support 130 includes a guide sleeve 131 and a hinge 132, the guide sleeve 131 is fixedly connected to the fixed frame 101, the guide sleeve 131 has a guide hole 133; the pulley 118 is hingedly connected to one end of the hinge 132, and the other end of the hinge 132 is provided with The guide pin 134 and the spring 115 are disposed between the guide pin 134 and the bottom surface of the guide hole 133 . Please refer to FIG. 4 for the connection structure between the pulley 118 and the first bracket 130 .

FIG. 5 is a schematic structural diagram of the pulley 118 in FIG. 4 . Referring to FIG. 5 , the pulley 118 is provided with an annular sliding groove 125 along the circumference, and the second steel wire segment 215 fits in the annular sliding groove 125 . An annular friction belt 126 is disposed in the annular chute 125 , and the second steel wire segment 215 fits on the surface of the friction belt 126 .

FIG. 6 is a schematic diagram of the connection structure of the first pedal 111 , the second pedal 112 , the third pedal 113 , the fourth pedal 114 and the fixing frame 101 in FIG. 2 . 2 and 6, the transmission structure 100 also includes a second bracket 141, a first pedal 111, a second pedal 112, a third pedal 113, a fourth pedal 114; a first connecting rod 121, a second connecting rod 122, The third connecting rod 123 , the fourth connecting rod 124 ; the first connecting part 151 and the second connecting part 152 . The first connecting portion 151 and the second connecting portion 152 are respectively rotatably connected to two sides of the second bracket 141 . The first connecting rod 121 and the third connecting rod 123 are connected to both ends of the first connecting part 151 respectively, and the first connecting rod 121 and the third connecting rod 123 are in line, and the first connecting part 151 is rotatably connected to the second bracket 141 ; The second connecting rod 122 and the fourth connecting rod 124 are respectively connected to the two ends of the second connecting part 152, and the second connecting rod 122 and the fourth connecting rod 124 are collinear, and the second connecting part 152 is rotatably connected to the second bracket 141. The fixing frame 101 includes a horizontal section 127 and an inclined section 128 extending from a left end of the horizontal section 127 in an obliquely upward direction. The first rotating shaft 102 is rotatably connected to the horizontal section 127 near its left end, and the second rotating shaft 103 is rotatably connected to the horizontal section 127 near its right end. The first bracket 130 is connected to the junction of the horizontal section 127 and the inclined section 128 , and the pulley 118 is located on the left side of the first bracket 130 . The second bracket 141 is connected to the inclined section 128 .

FIG. 7 is a schematic diagram of the cooperative relationship between the transmission rope 210 and the guide wheel 119 , the third flywheel 108 , the pulley 118 and the second flywheel 107 . Please refer to FIG. 7 , the transmission rope 210 includes a first end 211, a second end 212, and a first steel wire segment 213, a first chain segment 214, and a second steel wire sequentially connected between the first end 211 and the second end 212. Segment 215 and second segment 216. The first wire segment 213 corresponds to the guide wheel 119 , the first chain segment 214 corresponds to the third flywheel 108 , the second wire segment 215 corresponds to the pulley 118 , and the second chain segment 216 corresponds to the second flywheel 107 . The first end 211 of the transmission rope 210 is connected to the middle position of the length direction of the second connecting rod 122, and the second end 212 of the transmission rope 210 walks around the guide wheel 119, the third flywheel 108, the pulley 118, the second flywheel 107 and Connected to the third connecting rod 123. In order to make the transmission rope 210 in the process of pulling, the first steel wire segment 213, the first chain segment 214, the second steel wire segment 215, and the second chain segment 216 can always correspond to the guide wheel 119, the third flywheel 108, the pulley 118, The second flywheel 107, in the present embodiment, the length of the first steel wire section 213 is greater than the contact length of the transmission rope 210 and the guide wheel 119; the length of the first chain segment 214 is greater than the contact length of the transmission rope 210 and the third flywheel 108; The length of the second wire segment 215 is greater than the contact length between the transmission rope 210 and the pulley 118 ; the length of the second chain segment 216 is greater than the contact length between the transmission rope 210 and the second flywheel 107 .

FIG. 8 is a schematic structural diagram of the second flywheel 107 and the third flywheel 108 in this embodiment. Please refer to Fig. 8, the second flywheel 107, the 3rd flywheel 108 are single-stage flywheels, single-stage flywheels comprise overcoat 301, flywheel inner tooth 302, jack 303, core 304, overcoat 301 is provided with external teeth, core 304 and the first The two rotating shafts 103 are fixedly connected.

The working principle of the bicycle 600 in the present embodiment: by setting the second flywheel 107, the 3rd flywheel 108 on both sides of the sprocket wheel 104 of the first rotating shaft 102, pedals are set on the fixed mount 101 and the second support 141 (the second One pedal 111, the second pedal 112, the third pedal 113, the fourth pedal 114), the pedal connecting rod (comprising the first connecting rod 121, the second connecting rod 122, the third connecting rod 123, the fourth connecting rod 124) , and rotate and set, when the first pedal 111 and the third pedal 113 reciprocate up and down, the transmission rope 210 is pulled by the first connecting rod 121 and the third connecting rod 123, and under the drive of the transmission rope 210, the second flywheel 107, The third flywheel 108 rotates at a certain angle in turn to drive the sprocket 104 to rotate, and then drives the rear wheel 602 through the sprocket 104, and the rear wheel 602 drives the whole vehicle to move. Similarly, the forward movement of the bicycle 600 can be realized by stepping on the second pedal 112 and the fourth pedal 114 back and forth, and the human body can choose to use the left foot in front, the right foot in the back or the left foot in the back and the right foot in front. The bicycle 600 can adapt to users with different habits and requirements. The bicycle 600 exerts force up and down, which improves the existing bicycle 600, which has low utilization efficiency of the human body's exertion and strenuous pedaling. Riding the bicycle 600 also has the advantages of energy saving, environmental protection and fitness. In addition, since the bicycle 600 needs to overcome resistances such as the static friction between the front and rear wheels 602 and the ground when starting, the human body needs to exert a large force to start the bicycle, which has the disadvantage of laborious starting. 132 and spring 115 are elastically connected to the fixed frame 101. When starting, the force applied to the pulley 118 along its radial direction after the transmission rope 210 is pulled can compress the spring 115 in an appropriate amount, so that the pulley 118 moves to the fixed frame 101 by a certain amount. Distance, so that the transmission rope 210 can be pulled more easily, so the bicycle 600 in the embodiment of the utility model also has the beneficial effect of starting with less effort.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. For those skilled in the art, the present utility model can have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. a kind of bicycle, it is characterised in that：

The bicycle includes drive mechanism, also includes front-wheel, trailing wheel, handle, handlebar stem, cushion；

The drive mechanism includes fixed mount, first rotating shaft, the second rotating shaft, sprocket wheel, the first flywheel, chain；

The first rotating shaft and second rotating shaft are rotationally connected with the fixed mount, and the first rotating shaft and described respectively Two shaft parallels；

The sprocket wheel is connected to the first rotating shaft, and first flywheel is connected to second rotating shaft；First flywheel with Connected by the chain drive between the sprocket wheel；

The rear wheel is connected to second rotating shaft；

The drive mechanism also includes the second flywheel, the 3rd flywheel, pulley, directive wheel, transmission rope；

Second flywheel and the 3rd flywheel are connected to the first rotating shaft, and second flywheel and institute spaced reciprocally State the same side that the 3rd flywheel is located at the sprocket wheel；

The fixed mount is connected with first support, and the pulley is hinged in the first support, and the axis direction of the pulley Vertical with the axis direction of the first rotating shaft；

The first support includes guide pin bushing and articulated elements, and the guide pin bushing is fixedly connected on the fixed mount, and the guide pin bushing has leads Hole；The pulley is articulated and connected in one end of the articulated elements, and the other end of the articulated elements is provided with pilot pin, the pilot pin and institute Spring is provided between the bottom surface for stating guide hole；

The drive mechanism also includes second support, the first pedal, the second pedal, the 3rd pedal, the 4th pedal；First connecting rod, Second connecting rod, third connecting rod, fourth link；First connecting portion, second connecting portion；

The first connecting portion and the second connecting portion are rotationally connected with the both sides of the second support respectively；

The first connecting rod is connected to the two ends of the first connecting portion with the third connecting rod, and the first connecting rod with The third connecting rod is conllinear, and the first connecting portion is rotationally connected with the second support；The second connecting rod and the described 4th Connecting rod is connected to the two ends of the second connecting portion, and the second connecting rod is conllinear with the fourth link, and described second Connecting portion is rotationally connected with the second support；

The transmission rope includes first end, the second end, and be connected in turn between the first end and second end One steel wire section, the first segment, the second steel wire section and the second segment；

The first steel wire section is corresponding with the directive wheel, and first segment is corresponding with the 3rd flywheel, second steel Silk section is corresponding with the pulley, and second segment is corresponding with second flywheel；

The first end of the transmission rope is connected to the centre position of the length direction of second connecting rod, the second end of the transmission rope according to Secondary bypass directive wheel, the 3rd flywheel, pulley, the second flywheel and be connected on the third connecting rod；

After first pedal is trampled decline, the third connecting rod is rotated up, and drives the second end of the transmission rope to rise, And the transmission rope pulls second flywheel to rotate forward, second flywheel drives the first rotating shaft to rotate, described first turn Axle drives the sprocket wheel to rotate, and the 3rd flywheel is inverted under the drive of the transmission rope, and the transmission rope is led by described The lower second connecting rod is pulled down to wheel, second pedal declines, and the 4th pedal rises.

2. bicycle according to claim 1, it is characterised in that：

The fixed mount includes horizontal segment and the tilting section extended from the left end of the horizontal segment along the direction for tilting upward；

The first rotating shaft is rotationally connected with the horizontal segment at its left end, and second axis of rotation is connected to the water Flat section is at its right-hand member；

The first support is connected to the horizontal segment and the tilting section joint, and the pulley is located at the first support Left side；

The second support is connected to the tilting section.

3. bicycle according to claim 1, it is characterised in that：

The first rotating shaft is rotated with the fixed mount by bearing with second rotating shaft respectively and is connected.

4. bicycle according to claim 1, it is characterised in that：

Second flywheel, the 3rd flywheel are single freewheel, and the single freewheel includes overcoat, flywheel internal tooth, very heavy, fuse, The overcoat is provided with external tooth, and the fuse is fixedly connected with the second rotating shaft.

5. bicycle according to claim 1, it is characterised in that：

The pulley is provided with annular groove circumferentially, and the second steel wire section coordinates in the annular groove.

6. bicycle according to claim 5, it is characterised in that：

The friction belt of annular is provided with the annular groove, and the second steel wire section is matched with the surface of the friction belt.

7. bicycle according to claim 1, it is characterised in that：

Second flywheel is symmetricly set in the both sides of the fixed mount with the 3rd flywheel.

8. bicycle according to claim 1, it is characterised in that：

The length of the first steel wire section is more than the contact length of the transmission rope and the directive wheel；The length of first segment Degree is more than the contact length of the transmission rope and the 3rd flywheel；The length of the second steel wire section more than the transmission rope with The contact length of the pulley；The length of second segment is more than the contact length of the transmission rope and second flywheel.

9. bicycle according to claim 1, it is characterised in that：

Second flywheel is identical with the 3rd flywheel size.

10. the bicycle according to any one of claim 1 to 9, it is characterised in that：

The handle is connected to the fixed mount by the handlebar stem, and the front-drive is connected to the one of the handlebar stem End；

The cushion is fixedly connected on the fixed mount by rod member.