JP2004114710A - Bicycle rear wheel drive and bicycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bicycle rear wheel drive by which it makes possible to make a bicycle small and compact and which is easy to handle and can cause the variety of the appearance of the bicycle in comparison with the chain transmission devices of conventional bicycles and the bicycle mounting the same. <P>SOLUTION: The bicycle rear wheel drive 3 in the bicycle A has a crank 31 rotatably supported at the predetermined position of a bicycle frame 4, a driving sun gear 32 supported by a crank rotating shaft 311, a driven planet gear 33 having a diameter smaller than that of the gear 32, an intermediate driving frictional wheel 34 rotating with the planet gear, a supporting arm 35 supported pivotably relative to the crank rotating shaft 311 and rotatably supporting the gear 33 and the frictional wheel 34. The arm 35 supports the planet gear 33 such that the it mesh with the sun gear 32 and can revolute around the sun gear 32 and supports the intermediate driving frictional wheel 34 such that it can reciprocate between the position P1 where it comes in contact with a bicycle rear wheel circumferential face and the lowered position P2 apart from that position by the revolution of the planet gear 33. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a bicycle rear wheel drive device and a bicycle.
[0002]
[Prior art]
In general, a conventional bicycle generally has a crank with a pedal rotatably supported at a fixed position on a bicycle frame, and a large gear for driving provided on a rotating shaft of the crank, while a bicycle rear wheel is provided. The driven small gear is provided, and an endless chain is wound around the driving large gear and the driven small gear.
[0003]
When the person riding the bicycle turns the pedal-equipped crank, power is transmitted from the large gear to the small gear of the rear wheel via an endless chain, and the rear wheel rotates and the bicycle runs.
[0004]
[Problems to be solved by the invention]
However, a conventional bicycle having such a basic structure generally has a structure shown in FIG. 6 when viewed from the rear wheel side. That is, a driven small gear 93 around which an endless chain 94 is wound is provided on the rotation shaft 951 of the rear wheel 95 between a driving large gear 92 rotated together with the pedal-equipped crank 91. The driven small gear 93 is disposed on the outside along the rear wheel 95 and is provided on the rear wheel shaft 951. Therefore, the left-right width W ′ inside the frame portion supporting the rear wheel shaft 951 and the surrounding structure is increased by at least the provision of the driven small gear 93.
[0005]
Also, since a chain 94 is wound around the driven small gear 93 and the large gear 92 on the crank side disposed outside the rear wheel 95, the chain also protrudes sideways, and when a chain cover is provided for safety, It protrudes further sideways.
[0006]
In FIG. 6, BK is a main part of the band brake device provided for the rear wheel axle 951, 96 is a part of the bicycle frame on which the rear wheel 95 is mounted, and 97 is a saddle. The other parts of the bicycle are not shown.
[0007]
Such a chain transmission hinders downsizing and downsizing of the bicycle. In particular, in a foldable bicycle that requires miniaturization and compactness, such a transmission has been an obstacle. Furthermore, the handling of the bicycle is made more difficult, for example, other objects easily bite between the chain and the gears. In particular, in the case of a foldable bicycle, handling of the foldable bicycle is made more difficult, for example, when the foldable bicycle is stored in a folded state, other objects easily bite between the chain and the gear.
[0008]
Also, chain transmissions are very mechanical and oppressive in appearance and do not have a desirable appearance for some people.
[0009]
Therefore, an object of the present invention is to provide a spinning rear wheel drive device that enables a smaller and more compact bicycle, is easier to handle, and can provide a variety of bicycle appearances as compared with a conventional bicycle chain transmission device. I do.
[0010]
Another object of the present invention is to provide a bicycle, such as a foldable bicycle, which employs such a bicycle rear-wheel drive device, whereby the bicycle can be reduced in size and size, can be easily handled, and can provide a variety of bicycle appearances. .
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention
A crank rotatably supported at a fixed position on the bicycle frame,
A driving sun wheel supported on a rotating shaft of the crank;
A driven planetary wheel for the sun wheel;
An intermediate drive friction wheel that rotates with the planet wheel,
A support arm rotatably supported by the crank rotation shaft and rotatably supporting the planetary wheel and the intermediate drive friction wheel,
The support arm supports the planetary wheel in contact with the sun wheel so that the planetary wheel can be driven to rotate and revolve around the sun wheel, and the intermediate driving friction wheel is revolved around the planetary wheel on the bicycle rear wheel peripheral surface. A bicycle rear wheel drive device that reciprocally supports between a contact position and a descending position away from the contact position, and a sun equipped with such a rear wheel drive device, for example, a folding bicycle. The wheel and the driven planet wheel may be friction wheels that rotate frictionally in contact with each other, but the sun wheel should be a sun gear to ensure power transmission and smoothness, and the driven planet wheel should be a planet gear that meshes with the sun gear. Is desirable.
[0012]
In the bicycle rear wheel drive device of the present invention and the bicycle including the same, when the crank is not rotated, the driving sun wheel does not rotate, and the planetary wheel, the intermediate drive friction wheel, and the supporting frame that supports them are Take the position lowered by its own weight. At this time, the planet wheel descends while revolving around the sun wheel. In the lowered position, the intermediate drive friction wheel is separated from the bicycle rear wheel.
[0013]
When the crank is rotated in this direction to allow the bicycle to travel forward, the planetary wheel revolves around the sun wheel while revolving around, and the intermediate drive friction wheel contacts the rear wheel of the bicycle. Take. When the crank is further rotated in the above direction and the sun wheel is rotated, the planet wheel is further driven by this to rotate further, whereby the intermediate drive friction wheel is also rotated, and the intermediate drive friction wheel is in contact with the rear side of the bicycle. The wheel rotates frictionally. Thus, the bicycle can be driven forward.
[0014]
In this state, if the rotation of the crank in the direction in which the bicycle moves forward is stopped or slightly reversed, the intermediate drive friction wheel in contact with the rear wheel is pushed downward by the inertia rotation force of the rear wheel, and As a result, the intermediate drive friction wheel and the support arm rotate downward, and the planetary wheel takes a position where the intermediate drive friction wheel and the planet wheel are lowered while revolving around the sun wheel.
[0015]
When stopping the rotation of the crank in the bicycle forward direction, or slightly reversing the rotation while the bicycle is traveling forward, or turning the crank slowly than the crank rotation speed corresponding to the bicycle forward traveling speed When the rear wheel of the bicycle is in contact with the intermediate driving friction wheel and rotates the intermediate driving friction wheel in reverse, so that the crank may rotate in the bicycle forward direction at a speed corresponding to the bicycle traveling speed For example, a one-way clutch may be provided.
[0016]
That is, when the crank is rotated in the direction in which the bicycle runs, power transmission from the crank rotation shaft to the intermediate drive friction wheel is permitted, but power transmission from the intermediate drive friction wheel to the crank rotation shaft is not permitted. A directional clutch may be mounted between the crankshaft and the sun wheel or between the planet wheel and the intermediate drive friction wheel.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0018]
FIG. 1 shows a schematic configuration of a foldable bicycle according to the present invention.
[0019]
2 is a view of the rear wheel drive device and the like of the bicycle of FIG. 1 as viewed from the bicycle handle, and FIG. 3 is a view of the bicycle rear wheel and the rear wheel drive device and the like as viewed from the rear wheel side.
[0020]
The illustrated bicycle A includes a front wheel 1, a rear wheel 2, a rear wheel drive device 3, and a bicycle frame 4 that supports them.
[0021]
The bicycle frame 4 has a front part and a rear part.
[0022]
The front portion of the frame 4 includes a fork-shaped front wheel support portion 41 that rotatably supports the front wheel 1, a handle support portion 42 standing up therefrom, and a folded portion 43 extending rearward from the handle support portion 42. The handle 5 is detachably attached to the handle support section 42 and the height is adjustable.
[0023]
A rear portion of the frame 4 supports the rear wheel 2 rotatably and also supports a rear wheel driving device 3 in a substantially triangular portion 44, a saddle support portion 45 extending upward from the portion 44, and extending forward. It comprises a folded portion 46.
[0024]
The saddle 6 is detachably attached to the saddle support portion 45 and is adjustable in height.
[0025]
The folding portions 43 and 46 are connected to each other by a hinge 47 so as to be able to be folded in two. By operating the lever 471, the hinge 47 is fixed for using the bicycle, and the folding portions 43 and 46 are held in a straight line, In order to fold, the folding parts 43 and 46 can be folded in two.
[0026]
The rear wheel drive device 3 includes a pair of pedal-equipped cranks 31, a drive sun gear 32, a driven planetary gear 33, an intermediate drive friction wheel 34, and a support arm 35 that supports the gear 33 and the friction wheel 34.
[0027]
The pedal-equipped crank 31 is rotatably supported at a lower right position in FIG. 1 of a portion 44 supporting the rear wheel and the rear wheel drive device of the bicycle frame 4. The sun gear 32 is provided on a rotation shaft 311 of the crank so as to rotate therewith. One end of the support arm 35 is supported by the crank rotation shaft 311 so as to be rotatable relative thereto, and the planetary gear 33 and the intermediate drive friction wheel 34 are rotatable relative to the arm at the other end of the support arm 35. It is supported by. The planetary gear 33 and the intermediate drive friction wheel 34 are coaxial and rotate together.
[0028]
The planetary gear 33 has a smaller diameter than the sun gear 32, and the intermediate drive friction wheel 34 has a larger diameter than the planetary gear 33 and a smaller diameter than the sun gear 32. In this example, the planetary gear 33 and the intermediate drive friction wheel 34 make three rotations per rotation of the crank 31 and the sun gear 32. The rotation ratio between the sun gear 32, the planetary gear 33, and the intermediate drive friction wheel 34 is not limited to this. Other values may be set as long as the bicycle can be run.
[0029]
The support arm 35 supports the planetary gear 33 so that it can rotate while meshing with the sun gear 32, whereby the planetary gear 33 can revolve around the sun gear 32 while rotating.
[0030]
The intermediate drive friction wheel 34 can reciprocate between a position P1 at which the peripheral surface of the planetary gear 33 contacts the peripheral surface of the bicycle rear wheel 2 and a descending position P2 away from the position.
[0031]
The other parts of the bicycle are not shown.
[0032]
In the bicycle A shown in FIG. 1, when the crank 31 is not rotated, the driving sun gear 32 also does not rotate. At this time, the planetary gear 33, the intermediate drive friction wheel 34, and the support arm 35 that supports them are lowered while revolving around the sun gear 32 due to their own weight, as shown by the broken line in FIG. 1. The intermediate drive friction wheel 34 also takes a lowered position P2 away from the rear wheel 2 of the bicycle.
[0033]
When the crank 31 is rotated from this state in a direction for moving the bicycle A forward (in the clockwise direction in FIG. 1), the planetary gear 33 revolves around the sun gear 32 while revolving around the sun gear 32, and the intermediate gear is accordingly moved. A position P1 at which the driving friction wheel 34 contacts the rear wheel 2 of the bicycle is taken. Further, when the crank 31 is rotated clockwise in the figure and the sun gear 32 is rotated, the planetary gear 33 is further driven by the rotation, whereby the intermediate driving friction wheel 34 is also rotated. , And the rear wheel 2 of the bicycle that is in contact therewith frictionally rotates. Thus, the bicycle A can be run forward.
[0034]
In this state, when the rotation of the crank 31 in the above direction is stopped or slightly reversed, the intermediate drive friction wheel 34 in contact with the rear wheel 2 is pushed downward by the inertial rotation force of the rear wheel 2. The intermediate drive friction wheel 34 and the support arm 35 rotate downward, and the planetary gear 33 revolves around the sun gear 32 downward. Thus, the intermediate driving friction wheel 34 and the planetary gear 33 take the position P2 in which they are both lowered. In this state, the rear wheel 2 can rotate freely.
[0035]
When the bicycle A shown in FIG. 1 is stored in a predetermined place or the like, the handle 5 and the saddle 6 can be removed from the bicycle frame 4 and the bicycle frame portions 43 and 46 can be folded in two at the hinge 47. The reverse is also possible.
[0036]
In the rear wheel drive device 3 described above and the bicycle A employing the same, the inner width W1 (see FIG. 3) of the portion 441 supporting the rear wheel 2 in the rear portion 44 of the bicycle frame is the same as that of the conventional bicycle. Compared to the inner width W 'of the chain transmission device and the bicycle employing the same (see FIG. 6), there is no need to provide a driven small gear on the outer side of the rear wheel. Can be
[0037]
In the bicycle A, in order to make the inner width of the rear wheel supporting portion 441 of the bicycle frame smaller and more compact, the rear wheel brake is not a band brake but a type in which the rear wheel rim can be sandwiched from both sides. , Has decided to employ a brake known per se. However, even if a band brake is employed, the inner width W1 of the frame portion 441 can still be smaller than the conventional inner width W '.
[0038]
Although not limited thereto, for example, by forming the width (thickness) of the friction wheel 34 to 30 mm to 40 mm and each width (thickness) of the sun gear 32 and the planetary gear 33 to about 15 mm, the sun gear 32 As shown in FIG. 4, the combination width of the planetary gear 33 and the friction wheel 34 can be set to a width that fits inside the inner width W2 (generally, about 92 mm) of the fork-shaped front wheel supporting portion 41. Yes, the bicycle can be made smaller and more compact.
[0039]
Further, compared to a bicycle employing a conventional chain transmission device, the bicycle does not require a laterally protruding chain or a chain cover, so that the bicycle can be made smaller and more compact in that respect.
[0040]
Further, since the rear wheel drive device 3 described above and the bicycle A employing the same use the friction transmission by the intermediate drive friction wheel 34 for the rear wheel drive, the rear wheel drive device 3 and the bicycle A adopting the same are used. There is no problem that other objects easily bite between the gear and the gear, and the handling is easier. In particular, in the case of a foldable bicycle as shown in the figure, handling such as folding and storage is easy.
[0041]
In addition, since a transmission different from the chain transmission is employed, the appearance of the bicycle can be varied.
[0042]
In the bicycle A shown in FIG. 1, when the bicycle is traveling forward, when the rotation of the crank 31 in the bicycle forward direction is stopped or when the crank 31 is to be rotated slightly in the reverse direction, the crank 31 contacts the intermediate drive friction wheel 34. When the rear wheel 2 rotates the intermediate drive friction wheel 34 in the opposite direction, and the crank 31 is likely to rotate in the bicycle forward direction, for example, a one-way clutch can be provided for safety. .
[0043]
FIG. 5 shows an example of a bicycle A provided with a one-way clutch. In the bicycle B shown in FIG. 5, when the crank 31 is rotated in the direction in which the bicycle runs, the crank rotation is transmitted to the sun gear 32, while the crank 31 is rotated via the one-way clutch CL that allows the crank 31 to rotate relative to the sun gear 32. The sun gear 32 is supported on a crank rotation shaft 311.
[0044]
Such a one-way clutch CL only has to function in such a manner, but in the example of FIG. 5, the one-way clutch CL has the same basic structure as that conventionally used for the rear wheel of a bicycle.
[0045]
By providing such a one-way clutch CL, the rotation of the crank 31 is stopped or reversed during running of the bicycle, or the rotation speed of the sun gear 32 is lower than the rotation speed of the sun gear 32 in a state where the sun gear 32 is driven to rotate from the rear wheel 2 side. The crank 31 can be turned slowly at a speed.
[0046]
In the bicycle B of FIG. 5, the one-way clutch CL is mounted between the crank rotation shaft 311 and the sun gear 32, but between the planetary gear 33 and the friction wheel 34, more specifically, the support arm 35 here. It may be provided between the rotating shaft of the rotatably supported planetary gear 33 and the friction wheel 34.
[0047]
Further, in the bicycle B, an arm stopper 71 is provided for appropriately restricting the lowering position of the support arm 35 to facilitate the start of bicycle running, and for limiting the amount of lowering of the support arm 35 and the like for safety. It is. The stopper 71 is supported by a stopper support arm 7 protruding from the bicycle frame portion 44. With this stopper 71, the lowering position of the support arm 35 is set to a position P2 'above the position P2.
[0048]
【The invention's effect】
As described above, according to the present invention, there is provided a spinning rear wheel drive device that can reduce the size and size of a bicycle as compared with a conventional bicycle chain transmission device, is easy to handle, and can provide a variety of bicycle appearances. Can be provided.
[0049]
Further, the present invention can provide a bicycle, for example, a folding bicycle, which adopts such a bicycle rear wheel drive device, thereby enabling miniaturization and compactness, and is easy to handle and can provide a variety of bicycle appearances. .
[Brief description of the drawings]
FIG. 1 is a schematic side view of an example of a bicycle according to the present invention.
FIG. 2 is a view of a rear wheel drive device and a rear wheel of the bicycle of FIG. 1 as viewed from a bicycle handle;
FIG. 3 is a view of a bicycle rear wheel, a rear wheel drive device, and the like of the bicycle of FIG. 1 as viewed from a rear wheel side.
FIG. 4
FIG. 2 is a view of a front wheel and the like of the bicycle of FIG. 1 as viewed from a front side of the bicycle.
FIG. 5
It is a side view of the rear-wheel drive device part etc. of another example of the bicycle which concerns on this invention.
FIG. 6
It is a figure which shows roughly the rear wheel in a conventional bicycle, a chain transmission device, etc. from the back of a bicycle.
[Explanation of symbols]
A, B Foldable bicycle 1 Bicycle front wheel 2 Bicycle rear wheel 3 Rear wheel drive 31 Crank with pedal 311 Crank rotation shaft 32 Driving sun gear 33 Driven planetary gear 34 Intermediate drive friction wheel 35 Support arm 4 Bicycle frame 41 Front wheel support 42 Handle Supporting Section 43 Folding Section 44 Frame Portion 45 Supporting Rear Wheel and Rear Wheel Drive 45 Saddle Supporting Section 46 Folding Section 47 Hinge 471 Hinge Operating Lever 5 Handle 6 Saddle BK Main Portion of Rear Wheel Band Brake Device CL Clutch 7 Stopper Support arm 71 Arm stopper P1 Rear wheel contact position P2 of friction wheel 34, P2 'Lowering position of friction wheel 34

Claims (5)

A crank rotatably supported at a fixed position on the bicycle frame,
A driving sun wheel supported on a rotating shaft of the crank;
A driven planetary wheel for the sun wheel;
An intermediate drive friction wheel that rotates with the planet wheel,
A support arm rotatably supported by the crank rotation shaft and rotatably supporting the planetary wheel and the intermediate drive friction wheel,
The support arm supports the planetary wheel in contact with the sun wheel so that the planetary wheel can be driven to rotate and revolve around the sun wheel, and the intermediate driving friction wheel is revolved around the planetary wheel on the bicycle rear wheel peripheral surface. A bicycle rear wheel drive device that reciprocates between a contact position and a descending position away from the contact position. The bicycle rear wheel drive device according to claim 1, wherein the sun wheel is a sun gear, and the driven planet wheel is a planet gear that meshes with the sun gear. A one-way clutch that permits power transmission from the crankshaft to the intermediate drive friction wheel when rotating the crank in the direction in which the bicycle runs, but does not allow power transmission from the intermediate drive friction wheel to the crankshaft; The bicycle rear wheel drive device according to claim 1 or 2, wherein is mounted between the crank rotation shaft and the sun wheel or between the planetary wheel and the intermediate drive friction wheel. A bicycle comprising the bicycle rear wheel drive device according to claim 1, 2 or 3. The bicycle according to claim 4, wherein the bicycle is a folding bicycle.

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