TWI771860B - Bicycle rear wheel drive mechanism - Google Patents

Abstract

A bicycle rear-wheel drive mechanism includes a tower base combined with a chainring assembly, the tower base has an accommodating hole in the axial direction, and a first threaded portion and a second threaded portion are formed in the accommodating hole Wall surface. An extension gear plate assembly is sleeved on the axial outside of the tower base. One end of the locking ring is a shaft tube part combined with a stop part, wherein the outer peripheral surface of the shaft tube part has a locking thread, the shaft tube part extends into the receiving hole of the tower base, and the locking thread is engaged The first threaded portion or the second threaded portion. In the present invention, the combination of the first threaded portion and the second threaded portion of the tower base and the locking ring can be used with extension chainring assemblies with different numbers of teeth.

Description

bicycle rear wheel drive

The invention relates to the technical field of a bicycle, in particular to a bicycle rear wheel drive mechanism.

Generally speaking, a typical bicycle rear derailleur flywheel group generally includes a freewheel base combined with a hub, and several flywheels fixed to the outer diameter portion of the freewheel base at equal intervals in order of the number of teeth. With the continuous pursuit of bicycle weight, speed and shifting function, the shifting bicycles on the market can no longer satisfy people's pursuit, and the maximum speed of the bicycle is determined by the number of the smallest chainrings of the flywheel. People's breakthroughs in the existing speed and variable speed range are urgently needed. How to further improve the maximum speed and shifting performance of bicycles is a common problem faced by people.

In order to increase the minimum number of teeth of the flywheel, the industry has designed additional flywheel chainrings. However, the flywheel chainrings with different tooth numbers need to be matched with different types of freewheel bases, thus causing the rider to increase the inconvenience of the flywheel chainrings.

The purpose of the present invention is to provide a bicycle rear wheel drive mechanism, which has the effect of using the same freewheel base to install locking rings for different tooth pieces.

In order to achieve the above-mentioned purpose and effect, the present invention provides a bicycle rear wheel drive mechanism comprising a tower base combined with a chainring group, wherein the tower base is a cylindrical member, and the chainring group is stacked by a plurality of chainrings with different numbers of teeth. Combination, one end is the maximum tooth number chainring, the other end is the minimum tooth number chainring, the chainring group is sleeved on the axial outside of the tower body, and the minimum tooth number chainring is adjacent to a free end of the tower body , which is characterized in that: the axial direction of the freewheel has an accommodating hole, a first threaded portion and a second threaded portion are formed on the inner wall surface of the accommodating hole, and the first threaded portion is adjacent to the second threaded portion part, and the first threaded part is closer to the free end of the free end than the second threaded part.

An extended chainring assembly is a single chainring and the number of teeth is less than the number of teeth of the minimum toothed chainring, the extended chainring assembly is sleeved on the axial outside of the tower body and is adjacent to the minimum toothed chainring; a locking ring , one end of a shaft tube part is combined with a stop part, wherein the outer peripheral surface of the shaft tube part has a locking thread, the shaft tube part extends into the accommodating hole of the freewheel, and the locking thread engages the first thread part, the resisting part resists the extended chainring assembly.

In one embodiment, the first threaded portion and the second threaded portion are formed in the circumferential direction of the inner wall surface of the accommodating hole, and the inner diameter of the first threaded portion is larger than the inner diameter of the second threaded portion .

In one embodiment, the inner wall surface of the accommodating hole has a first engagement portion and a second engagement portion, the second engagement portion is adjacent to the first engagement portion, and the first engagement portion and the second engagement portion An adjacent position of the engaging portion has a flange, the first threaded portion is formed in the circumferential direction of the first engaging portion, and the second threaded portion is formed in the circumferential direction of the second engaging portion.

In one embodiment, the inner wall surface of the chainring set has an insertion groove, the insertion groove is close to the chainring with the minimum number of teeth, and one end of the first extending chainring has an extension portion, and the extension The outer peripheral surface of the part has an inserting part, the extending chainring assembly is sleeved on the axial outer part of the tower base, and the inserting part is inserted into the inserting groove.

In one embodiment, the inner wall surface of the extended chainring assembly has a stop groove, the shaft tube portion of the locking ring extends into the accommodating hole of the freewheel body, and the stop portion is abutted against the stopper. retaining groove.

Hereinafter, according to the purpose and effect of the present invention, preferred embodiments are given and described in detail with the accompanying drawings.

10: Bike

12: Frame

14: Wheels

16: Wheels

20: Drive sprocket

22: Pedal crankset

24: Rear wheel drive mechanism

26: Chain

30: Taki

31: Wheels

32: Free end

34: accommodating hole

340: The first engaging part

342: Second engaging part

344: Flange

36: The first thread part

38: Second thread part

40: Chainset

42: Maximum number of teeth chainring

44: Minimum tooth number chainring

46: Embedded slot

50: The first extended chainring group

51: Extensions

52: Embedded part

60: The first locking ring

62: Axle tube part

64: Stop part

66: Locking thread

70: The second extended chainring group

72: The first extension chainring

74: Second extension chainring

76: Stop groove

78: Extensions

79: Embedded Department

80: Second locking ring

82: Axle tube part

84: Stop

Fig. 1 is a schematic diagram showing the position of the present invention arranged on a variable speed bicycle.

Fig. 2 is a cross-sectional view of the present invention, showing a state in which the first extended chainring group is mounted on the tower base.

Fig. 3 is a cross-sectional view of the present invention, showing a state in which the second extended chainring group is mounted on the tower base.

FIG. 4 is a schematic view of the structure of the present invention, showing that the second locking ring fixes the second extension sprocket set on the tower base.

Please refer to FIG. 1, which discloses a bicycle 10 and a frame 12 with wheels 14 and 16 respectively disposed at the front and rear, wherein the wheel 14 is called the front wheel, and the wheel 16 is called the rear wheel. Two opposite sides of a drive chainring 20 are respectively matched with a pedal crank set 22 . A rear wheel drive mechanism 24 of the bicycle 10 is mounted on the wheel 16 , and a chain 26 links the drive chainring 20 and the rear wheel drive mechanism 24 . In this way, stepping on the pedal crank set 22 makes the driving chain 20 drive the chain 26 to rotate, thereby driving the rear wheel drive mechanism 24 and the wheel 16 to rotate, so that the bicycle 10 can move forward.

Please refer to FIG. 2 , the rear-wheel drive mechanism 24 includes a freewheel base 30 combined with a chainring group 40 . The tower base 30 is a cylindrical member, two opposite ends of the tower base 30 are open, one end of the tower base 30 can be defined as a free end 32, and the other end of the tower base 30 is connected to a hub 31, The function and function of the wheel hub 31 are the same as those of the conventional wheel hub, and will not be described in detail here. An accommodating hole 34 is formed in the axial interior of the tower base 30 , and further, the accommodating hole 34 penetrates two opposite ends of the tower base 30 .

The inner wall surface of the accommodating hole 34 has a first engaging portion 340 and a second engaging portion 342, the second engaging portion 342 is adjacent to the first engaging portion 340, and the first engaging portion 340 engages with the second engaging portion 342 There is a flange 344 adjacent to the portion 342 , so that there is a drop between the first engaging portion 340 and the second engaging portion 342 , and the radius of the first engaging portion 340 is larger than the radius of the second engaging portion 342 .

This embodiment has a first threaded portion 36 and a second threaded portion 38 . The first threaded portion 36 and the second threaded portion 38 are formed in the circumferential direction of the inner wall surface of the accommodating hole 34 , the first threaded portion 36 is adjacent to the second threaded portion 38 , and the first threaded portion 36 The free end 32 of the freewheel body 30 is closer than the second threaded portion 38 . Specifically, the first threaded portion 36 is formed in the circumferential direction of the first engaging portion 340 , and the second threaded portion 38 is formed in the circumferential direction of the second engaging portion 342 , so that the first threaded portion 36 is The inner diameter is larger than the inner diameter of the second threaded portion 38 . The above-mentioned circumferential direction is the circumferential direction.

The chainring group 40 is formed by stacking and combining a plurality of chainrings with different numbers of teeth. One end is a chainring 42 with a maximum number of teeth, and the other end is a chainring 44 with a minimum number of teeth. The inner wall surface of the chainring group 40 has an insertion groove 46 , the insertion groove 46 is recessed at one end of the chainring group 40 and is close to the chainring with the minimum number of teeth 44. The chainring set 40 is sleeved on the axial outer portion of the freewheel body 30 , and the minimum tooth number chainring 44 is adjacent to the free end 32 of the freewheeling body.

This embodiment further includes a first extension chainring set 50 , the first extending chainring group 50 is a first extending chainring and the number of teeth is smaller than the number of teeth of the minimum tooth number chainring 44 , such as the first extension chainring group The 50's chainring has 11 teeth. Further, an extension portion 51 extends from one end of the first extension chainring group 50 . An insertion portion 52 is formed on the outer peripheral surface of the extension portion 51 . The first extended chainring set 50 is sleeved on the axial outer portion of the freewheel body 30 , and the insertion portion 52 of the first extending chainring group 50 is inserted into the insertion groove 46 of the chainring group 40 . The first extended chainring group 50 is adjacent to the minimum tooth number chainring 44 .

This embodiment further includes a first locking ring 60 , and one end of the first locking ring 60 is a shaft tube portion 62 combined with a resisting portion 64 . A locking thread 66 is formed on the outer peripheral surface of the shaft tube portion 62 . The first locking ring 60 is mounted on the freewheel body 30 . Further, the shaft tube portion 62 extends into the accommodating hole 34 of the freewheel body 30 , and the locking thread 66 engages the accommodating hole 34 of the accommodating hole 34 . The first threaded portion 36 . The blocking portion 64 abuts against one end of the first extension chainring 50 , so that the first locking ring 60 abuts the first extension chainring 50 , thereby restricting the chainring 40 and the first extension tooth The assembly of the disk pack 50 is released from the freehub body 30 .

The resisting portion 64 disclosed in this embodiment is formed on the outer peripheral surface of one end of the first locking ring 60 , so the first locking ring 60 is locked to the freewheel base 30 , and the resisting portion 64 is pressed against The outer surface of the first extended chainring group 50 .

Please refer to FIGS. 3 and 4 , a second extension chainring set 70 includes a first extension chainring 72 connected to a second extension chainring 74 . The number of teeth of the first extension chainring 72 is greater than that of the second extension chainring 74 The number of teeth is smaller than the number of teeth of the minimum number of teeth of the chainring 40 , for example, the number of teeth of the chainring of the first extended chainring 72 is 11 teeth, and the number of teeth of the chainring of the second extended chainring 74 is 10 teeth. A blocking groove 76 is recessed on the inner wall surface of the second extending chain plate set 70 . An extension portion 78 extends from one end of the first extension chainring 72 of the second extension chainring group 70 , and an insertion portion 79 is formed on the outer peripheral surface of the extension portion 78 .

The second extended chainring group 70 is sleeved on the axial outer portion of the freewheel body 30 , and the inserting portion 79 of the second extending chainring group 70 is inserted into the insertion groove 46 of the chainring group 40 . The first extended chainring 72 is adjacent to the minimum tooth number chainring 44 .

A second locking ring 80 is mounted on the freewheel body 30 , further, the shaft tube portion 82 of the second locking ring 80 extends into the accommodating hole 34 of the freewheel body 30 . The locking thread 86 engages the second thread portion 38 of the accommodating hole 34 . The blocking portion 84 of the second locking ring 80 is inserted into the blocking groove 76 of the second extended chainring set 70 , so that the second locking ring 80 abuts the second extending chainring set 70 , thereby restricting The combination of the chainring group 40 and the second extending chainring group 70 is released from the freehub body 30 .

The resisting portion 84 disclosed in this embodiment is formed on the outer peripheral surface of one end of the second locking ring 80 , so the second locking ring 80 is locked to the freewheel base 30 , and the resisting portion 84 is pressed against The outer surface of the blocking groove 76 of the second extended chainring group 70 .

According to the above, the present invention has the following advantages:

1. The combination of the first threaded portion 36 and the second threaded portion 38 of the freewheel base 30 and the first locking ring 60 and the second locking ring 80 can match the first extension teeth with different numbers of teeth The disk group 50 and the second extended chainring group 70 .

2. The first threaded portion 36 and the second threaded portion 38 of the freewheel base 30 can support different first locking rings 60 and second locking rings 80 , so they have the effect of facilitating assembly.

3. The first locking ring 60 and the second locking ring 80 can be locked into and extended into the freewheel base 30 , so they will not be interfered by the frame 12 during installation.

The above are the preferred embodiments and design drawings of the present invention, but the preferred embodiments and design drawings are only for illustration and are not intended to limit the scope of the rights of the present invention. The scope of the rights covered by the content of the "Patent Application Scope" and the implementation thereof shall not depart from the scope of the present invention and shall be the scope of the applicant's rights.

24: Rear wheel drive mechanism

30: Taki

31: Wheels

32: Free end

34: accommodating hole

340: The first engaging part

342: Second engaging part

344: Flange

36: The first thread part

38: Second thread part

40: Chainset

42: Maximum number of teeth chainring

44: Minimum tooth number chainring

46: Embedded slot

50: The first extended chainring group

51: Extensions

52: Embedded part

60: The first locking ring

62: Axle tube part

64: Stop part

66: Locking thread

Claims (5)

A bicycle rear wheel drive mechanism comprises a tower base combined with a chainring group, wherein the tower base is a cylindrical member, the chainring group is formed by stacking and combining a plurality of chainrings with different numbers of teeth, and one end is the tooth with the largest number of teeth. The other end is the minimum tooth number chainring, the chainring group is sleeved on the axial outer part of the tower body, and the minimum tooth number chainring is adjacent to a free end of the tower body, and it is characterized in that: the free end of the tower body is There is an accommodating hole in the axial direction, a first threaded portion and a second threaded portion are formed on the inner wall surface of the accommodating hole, the first threaded portion is adjacent to the second threaded portion, and the first threaded portion is larger than the second threaded portion. The second threaded portion is closer to the free end of the freewheel body; wherein the first threaded portion and the second threaded portion are formed in the circumferential direction of the inner wall surface of the accommodating hole, and the inner portion of the first threaded portion The diameter is larger than the inner diameter of the second threaded portion; a first extended chainring group and a first locking ring; the first extended chainring group is smaller than the number of teeth of the minimum tooth number chainring, and can be sleeved on the freewheel base Axially outside and adjacent to the minimum tooth number chainring; the first locking ring has a locking thread corresponding to the first threaded portion; and a second extending chainring group and a second locking ring; the second The extended chainring group is smaller than the number of teeth of the minimum tooth number chainring, and can be sleeved on the axial outer part of the freewheel and adjacent to the minimum tooth number chainring; the second locking ring has a locking thread corresponding to the second thread Thereby, when the first extension chainring is selected to be assembled on the freewheel body, the locking thread of the first locking ring is used to engage the first threaded portion of the freewheel body, and the first locking The ring abuts against the first extension chainring set, so that the first extension chainring group is fixed to the freewheel body; when the second extension chainring is selected to be assembled on the freewheel body, use the second locking ring The locking thread engages the second thread of the freewheel body part, and the second locking ring abuts against the second extended chainring group, so that the second extending chainring group is fixed to the freewheel body. The bicycle rear wheel drive mechanism according to claim 1, wherein the inner wall surface of the accommodating hole has a first engaging portion and a second engaging portion, the second engaging portion is adjacent to the first engaging portion, and the first engaging portion is adjacent to the first engaging portion. An engaging portion has a flange adjacent to the second engaging portion, the first threaded portion is formed in the circumferential direction of the first engaging portion, and the second threaded portion is formed in the circumferential direction of the second engaging portion . The bicycle rear wheel drive mechanism as claimed in claim 1, wherein the inner wall of the chainring set has an insertion groove, and the insertion groove is close to the minimum tooth number chainring, the first extending chainring group and the second extending tooth One end of the disk assembly is respectively provided with an extension part, and the outer peripheral surface of the extension part has an insertion part, and the insertion part is inserted into the insertion groove. The bicycle rear wheel drive mechanism as claimed in claim 1, wherein the first locking ring and the second locking ring respectively have a shaft tube portion and a stop portion, and the shaft tube portion extends into the housing of the freewheel body A hole is provided, and the resisting portion resists the corresponding first and second extending chainrings respectively. The bicycle rear wheel drive mechanism according to claim 4, wherein the inner wall surfaces of the first extension chainring group and the second extension chainring group respectively have a stop groove, so that the corresponding first locking ring and the corresponding The shaft tube portion of the second locking ring extends into the accommodating hole of the freewheel base, and the blocking portion abuts against the blocking groove.

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