TWI726676B - Chainring of a bicycle - Google Patents

Abstract

A bicycle chainring comprises a plurality of teeth formed about periphery of a body, wherein the plurality of teeth includes a first tooth group and a second tooth group. The teeth of the first and second tooth groups are alternately and adjacently arranged, and the thickness of the tooth of the first tooth group is greater than the thickness of the tooth of the second tooth group. At least a part of the teeth of the first tooth group includes a first projection and a second projection, the first projection and the second projection are located on opposite sides of the tooth. The first protrusion and the second protrusion are staggered, and the first protrusion protrudes from a side of the body. At least a part of the teeth of the second tooth group are offset and close to a side of the body. In this way, the interference between the chain and the teeth of the chainring can be further reduced, and the wear of the chain can be reduced during the process of changing the position of the chain.

Description

Bicycle sprocket

The present invention relates to the technical field of a bicycle transmission system, in particular to a bicycle sprocket. The sprocket is installed on a frame for combining two crank pedal sets and engaging a chain.

Bicycles usually use a chain to connect a sprocket and a combination of a flywheel and a hub, or use a chain to connect a plurality of sprockets and a combination of a flywheel and the hub. When riding a bicycle with a chain drive system, the meshing management of the chain and the sprocket is particularly important for the safe and effective propulsion of the bicycle. However, changing the ratio of the sprocket to the flywheel will change the position of the chain and the chain line. Therefore, changing the position of the chain will also cause friction with the sprocket, which will cause obvious interference when the chain changes position.

US Patent No. 9182027 discloses a sprocket with plural teeth, and the plural teeth include a first group of teeth and a second group of teeth, wherein the thickness of the first group of teeth is greater than the thickness of the second group of teeth, and the first group of teeth The line connecting each tooth tip of the second set of teeth is offset from the center line of the thickness of the sprocket.

Taiwan Patent TW 201525329A discloses a sprocket with a plurality of convex teeth surrounding the outer circumference of a disc body. The plurality of convex teeth are composed of a plurality of first convex teeth, a plurality of second convex teeth, and at least one or more odd third convex teeth. The number of the plurality of first convex teeth is an even number, and the tooth surface has a convex block, The upper edge of the convex block extends to the tooth end surface, a plurality of second convex teeth and the third convex tooth system and a plurality of first convex teeth form a staggered arrangement, the number of the plurality of second convex teeth is an odd number, and the third convex tooth has Shorter length; by The combination of the above structure and a chain can make the transmission more smooth and reliable, and can also greatly reduce the occurrence of chain falling.

The embodiment of the present invention discloses a bicycle sprocket, which can further reduce the interference between the chain and the sprocket teeth of the sprocket, and reduce the wear of the chain during the process of changing the position of the chain.

In order to achieve the above-mentioned purpose and effect, the sprocket structure disclosed in this embodiment has a plurality of sprocket surrounding the outer periphery of a body. The two opposite side surfaces of the body are a first surface and a second surface. A part of the plurality of sprocket teeth is a first sprocket group, the other part is a second sprocket group, and the first and second sprocket groups The sprocket teeth of are arranged alternately and adjacent to each other, and the thickness of the sprocket of the first sprocket group is greater than the thickness of the sprocket of the second sprocket group. Furthermore, at least a part of the sprocket of the first sprocket group includes a first bump and a second bump, the first bump and the second bump are located on two opposite sides of the sprocket, the first A protrusion and the second protrusion are staggered, and the first protrusion protrudes from the first surface of the body; and at least a part of the sprocket of the second sprocket set deviates from the first surface of the body and The middle position of the second surface is close to the first surface.

In accordance with the objectives and effects of the present invention, the following is a detailed description of preferred embodiments and their structures in conjunction with the drawings.

10: chain

12: Outer link

13: chain hole

14: inner link

15: chain hole

20: Wheel hub

22: flywheel

24: rear wheel

26: Crank pedal set

30: sprocket

32: body

34: First side

36: second side

42: The first sprocket group

43: sprocket

431: first bump

432: second bump

433: Slope

44: The second sprocket group

45: sprocket

452: side

454: arc

456: Linear part

458: top

Figure 1 is a diagram showing the structure of a bicycle chain.

Figure 2 is a schematic diagram of the combination of bicycle sprocket, flywheel and chain.

Figure 3 is an external view of an embodiment of the present invention.

Figure 4 is a partial external view of an embodiment of the present invention.

Figure 5 is a partial external view of the combination of the sprocket and the chain in the embodiment of the present invention.

Figure 6 is a partial external view of an embodiment of the present invention.

Figure 7 is a schematic diagram of the structure of the thick sprocket according to the embodiment of the present invention.

Figure 8 is a schematic diagram of the structure of the thin sprocket according to the embodiment of the present invention.

Figure 9 is a schematic top view of the thin sprocket according to the embodiment of the present invention.

Figure 10 is a schematic diagram of the structure of the thin sprocket according to the embodiment of the present invention.

Figure 11 is a schematic diagram of the engagement of the thick sprocket, the thin sprocket and the chain according to the embodiment of the present invention.

Figure 12 is a structural diagram of the displacement of the thin sprocket relative to the chain according to the embodiment of the present invention.

Please refer to Fig. 1, a bicycle chain 10 generally includes an outer link 12 and an inner link 14, which are pivotally combined by a pin 16 respectively. The outer link 12 and the inner link 14 are alternately staggered, and the width of the chain hole 13 of the outer link 12 is greater than the width of the chain hole 15 of the inner link 14.

Please refer to Figure 2, the combination of a hub 20 and a flywheel 22 is installed in the center of a rear wheel 24, the chain 10 is used to connect the flywheel 22 and a sprocket 30, and the sprocket 30 is combined with two cranks Pedal set 26. Stepping on the crank 26 can cause the sprocket 30 to rotate and the chain 10 to rotate, and the rotating chain 10 drives the combination of the flywheel 22 and the hub 20 to make the rear wheel 24 rotate. It is understandable that when the chain 10 changes position, the angle of the chain line (the extension line of the chain) of the chain 10 will change, and the closer to the rear wheel 22, the greater the inclination angle of the chain 10 is.

Please refer to FIG. 3, the sprocket 30 disclosed in this embodiment includes a body 32 and a plurality of sprocket teeth. One of the two opposite side surfaces of the main body 32 is a first surface 34, and the other surface is a second surface 36. A plurality of sprocket is around the outer periphery of the main body 32, and a part of the sprocket is a first sprocket group 42, and the other part of the sprocket is It is a second sprocket group 44, and the sprocket 45 of the second sprocket group 44 and the sprocket 43 of the first sprocket group 42 are alternately and adjacently arranged.

Please refer to FIGS. 4 and 5, the thickness of the sprocket 43 of the first sprocket group 42 is greater than the thickness of the sprocket 45 of the second sprocket group 44. The sprocket 30 engages the chain 10, the sprocket 43 of the first sprocket group 42 is inserted into the chain hole 13 of the outer link 12, and the sprocket 45 of the second sprocket set 44 is inserted into the inner link 14的链孔15。 The chain hole 15.

Please refer to FIGS. 6 and 7, at least a part of the first sprocket group 42 of the present embodiment includes a first protrusion 431 and a second protrusion 432. Preferably, all the fastener elements 43 of the first fastener element group 42 include a first protrusion 431 and a second protrusion 432.

The first protrusion 431 and the second protrusion 432 are located on two opposite sides of the sprocket 43. In particular, the first protrusion 431 and the second protrusion 432 are staggered, and the first protrusion 431 The first surface 34 of the main body 32 protrudes. Furthermore, the root of the first protrusion 431 of the sprocket 44 of the first sprocket group 42 is an inclined portion 433, and the inclined portion 433 is connected to the main body 32.

Please refer to FIGS. 6 and 8, at least a part of the second sprocket group 44, the sprocket 45 deviates from the middle position of the first surface 34 and the second surface 36 of the main body 32 and is close to the first surface 34. Preferably, all the sprocket teeth 45 of the second sprocket group 44 are offset close to the first surface 34.

Please refer to FIG. 9, except that the sprocket 45 deviates from the middle position of the first surface 34 and the second surface 36 of the main body 32, one side 452 of the sprocket 45 is inclined with respect to the second surface 36.

Please refer to Figure 10, the sprocket 45 is opposite to the two adjacent sides of the sprocket 43, one of which has an arc portion 454 and the other has a linear portion 456, the arc portion 454 and the linear portion 456 The top 458 of the sprocket 45 is opposite and connected to one end. The arc portion 454 and the linear portion 456 extend downward from the edge of the top portion 458. The high HC of the curved portion 454 is about 30% to 45% of the total high HT of the sprocket 45. Similarly, the linear The height HL of the portion 456 is about 30% to 45% of the total height HT of the sprocket 45, but the height of the arc-shaped portion 454 and the linear portion 456 are not necessarily the same.

Please refer to FIG. 11, the sprocket 30 is engaged with the chain 10, the thick sprocket 43 is inserted into the chain hole 13 of the outer link 12, and the thin sprocket 45 is inserted into the chain hole 15 of the inner link 14. Thereby, the meshing effect of the sprocket 30 and the chain 10 can be improved.

Please refer to Figures 11 and 12, when the chain 10 changes position, especially when the chain 10 moves from the flywheel small sprocket to a large sprocket (not shown), the inclination angle of the chain 10 becomes larger, and the chain 10 The outer side of 10 (the side away from the frame) is closer to the sprocket 43 and 45. Since the sprocket 45 is close to the first side 34 of the main body 32, and the side 452 of the sprocket 45 is inclined with respect to the second surface 36, there is a larger gap between the chain 10 and the sprocket 45 The movable clearance reduces the interference between the chain 10 and the sprocket 45, and reduces the wear of the chain 10 when the chain 10 changes position.

In other words, when the chain 10 changes to a larger flywheel, the chain of the inner link 14 can flash into the side 452 of the sprocket 45 to have more space for movement, the chain of the outer link 12 The sheet can also flash into the recess of the side of the second protrusion 432 of the sprocket 43 to reduce interference. When the chain 10 changes toward a smaller flywheel, the chain pieces of the inner link 14 and the outer link 12 can respectively rest on a side surface of the sprocket 45 and the first protrusion 431 of the sprocket 43, As a result, the chain pieces of the outer chain link 12 and the inner chain link 14 are supported to achieve the function of stabilizing the chain stop.

The above-mentioned embodiments are merely illustrative of the technology and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with this technology can modify and change the above-mentioned embodiments without violating the technical principle and spirit of the present invention. Therefore, the scope of protection of the rights of the present invention should be listed in the scope of patent application described later. .

30: sprocket

32: body

34: first side

36: second side

42: The first sprocket group

43: sprocket

44: The second sprocket group

45: sprocket

Claims (6)

A bicycle sprocket, which is used to engage a transmission chain, comprises: a body, the opposite side surfaces of which are a first surface and a second surface; and a plurality of sprockets surround the periphery of the body and a part of the chain The teeth are a first sprocket group, and the other part of the sprocket is a second sprocket group. The sprocket of the second sprocket group and the sprocket of the first sprocket group are arranged alternately and adjacently, The thickness of the sprocket of the first sprocket group is greater than the thickness of the sprocket of the second sprocket group; wherein at least a part of the sprocket of the first sprocket group includes a first protrusion and a second protrusion, The first protrusion and the second protrusion are located on two opposite sides of the sprocket, the first protrusion and the second protrusion are staggered, and the first protrusion protrudes from the first surface of the body; Wherein, at least a part of the sprocket teeth of the second sprocket group deviates from the middle position of the first surface and the second surface of the body and is close to the first surface. The bicycle sprocket according to claim 1, wherein the root of the first protrusion of the sprocket of the first sprocket group is an inclined portion, and the inclined portion is connected to the body. The bicycle sprocket according to claim 1, wherein one side of the sprocket of the second sprocket group is inclined relative to the second surface of the body. The bicycle sprocket according to claim 1, wherein each sprocket of the second sprocket group is located between two sprockets of the first sprocket group, and the sprocket of the second sprocket group The two sides of the sprocket are opposite to the two sprocket teeth of the first sprocket group, and one side of the sprocket of the second sprocket group is an arc part, and the other side is a linear part. The bicycle sprocket according to claim 4, wherein the sprocket of the second sprocket group has a top, the arc-shaped part is opposite to the linear part and one end is connected to the top, the arc-shaped part and the linear part are self-contained The top edge extends downward. The bicycle sprocket according to claim 5, wherein the height of the arc portion of the sprocket of the second chain set is about 30% to 45% of the total height of the sprocket, and the height of the linear portion is the sprocket 30% to 45% of the total height.

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