JP7601918B2 - Bicycle Chain - Google Patents

Description

This disclosure relates to bicycle chains.

Patent Document 1 discloses technology related to bicycle chains. A pair of inner link plates of the chain are connected by a bushing. A pin that connects a pair of outer link plates is inserted into the bushing.

U.S. Pat. No. 4,642,078

However, conventional bicycle chains leave room for improvement in terms of how they operate when shifting gears. This disclosure proposes a bicycle chain that allows for smoother operation when shifting gears.

A bicycle chain according to a first aspect of the present disclosure comprises a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a bush, and a pin, and the first inner link plate includes a first inner link end portion including a first inner link hole having a first inner link central axis, a second inner link end portion including a second inner link hole having a second inner link central axis extending parallel to the first inner link central axis, a first inner link middle portion connecting the first inner link end portion and the second inner link end portion, a first inner link surface, and the first inner link plate. and a second inner link surface disposed on the opposite side of the first inner link surface in a first inner link axial direction relative to an inner link central axis, the second inner link plate including a third inner link end portion including a third inner link hole having a third inner link central axis, a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis, a second inner link intermediate portion connecting the third inner link end portion and the fourth inner link end portion, and when assembled into a bicycle chain, the second inner link plate includes a third inner link end portion including a third inner link hole having a third inner link central axis, a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis, a a third inner link surface configured to face the first inner link surface of the inner link plate, and a fourth inner link surface disposed on the opposite side of the third inner link surface in a second inner link axial direction relative to the third inner link central axis, the first outer link plate being configured to be adjacent to the first inner link plate in an assembled state of the bicycle chain so as not to sandwich another inner link plate or another outer link plate therebetween, a first outer link end portion including a first outer link hole having a first outer link central axis, and a second outer link surface extending parallel to the first outer link central axis. a second outer link end portion including a second outer link hole having an outer link central axis; a first outer link intermediate portion connecting the first outer link end portion and the second outer link end portion; a first outer link surface; and a second outer link surface disposed on the opposite side of the first outer link surface in a first outer link axial direction relative to the first outer link central axis, the second outer link plate being configured in the assembled state to be adjacent to the second inner link plate so as not to sandwich another inner link plate or another outer link plate therebetween; a third outer link end portion including a third outer link hole, a fourth outer link end portion including a fourth outer link hole having a fourth outer link central axis extending parallel to the third outer link central axis, a second outer link intermediate portion connecting the third outer link end portion and the fourth outer link end portion, a third outer link surface configured to face the first outer link surface of the first outer link plate in the first outer link axial direction in an assembled state of the bicycle chain, and a second outer link intermediate portion disposed on the opposite side of the third outer link surface in the second outer link axial direction with respect to the third outer link central axis, a fourth outer link surface having a bushing hole and adapted to be inserted into the first inner link hole and the third inner link hole when the bicycle chain is in an assembled state, the bushing has a first bush outer link intersection and a second bush outer link intersection, an outer circumferential surface of the bushing and a first outer link longitudinal centerline of the first outer link plate intersect with each other at the first bush outer link intersection and the second bush outer link intersection when viewed in the first outer link axial direction, the first bush outer link intersection being closer to the first outer link than the second bush outer link intersection a first outer link reference line extending parallel to the first outer link lateral centerline and passing through the first bush-outer link intersection point; a second outer link reference line extending parallel to the first outer link lateral centerline and passing through the first bush-outer link intersection point; a first outer link reference line extending parallel to the first outer link lateral centerline and passing through the first bush-outer link intersection point; a second outer link reference line extending parallel to the first outer link lateral centerline and passing through the first bush-outer link intersection point; The first outer link edge intersection is defined as a line passing through a point, and the first outer link edge intersection is a point where the first outer link longitudinal centerline of the first outer link plate and the first outer link edge of the first outer link end portion of the first outer link plate intersect with each other when viewed from the first outer link axial direction, and at least one first outer link chamfer is provided on the first outer link plate so as to be at least partially disposed between the first outer link reference line and the second outer link reference line in the first outer link longitudinal direction relative to the first outer link longitudinal centerline of the first outer link plate. According to the bicycle chain of the first side, since the pin is inserted into the bush, the bicycle chain has high rigidity, wear of the bicycle chain is suppressed, and at least one first outer link chamfer makes the operation of the bicycle chain smooth when changing gears. Furthermore, the driving noise when the bicycle chain is driven is reduced.

In a bicycle chain having a second side according to the first side, the at least one first outer link chamfered portion is provided on the second outer link surface. According to the bicycle chain having the second side, the first outer link chamfered portion allows the bicycle chain to move smoothly when shifting gears. Furthermore, the driving noise when the bicycle chain is driven is reduced.

In a bicycle chain having a third side according to the first or second side, the at least one first outer link chamfered portion is provided on the end portion of the second outer link. According to the bicycle chain having the third side, the first outer link chamfered portion allows the bicycle chain to move smoothly when shifting gears.

In a bicycle chain having a fourth side according to the third side, the at least one first outer link chamfered portion is provided on the second outer link surface. According to the bicycle chain having the fourth side, the first outer link chamfered portion allows the bicycle chain to move smoothly when shifting gears. Furthermore, the drive noise when the bicycle chain is driven is reduced.

In a bicycle chain according to any one of the first to fourth aspects, the at least one first outer link chamfered portion is provided in the middle of the first outer link. According to the bicycle chain according to the fifth aspect, the first outer link chamfered portion allows the bicycle chain to move smoothly when shifting gears.

In a bicycle chain having a sixth side according to the fifth side, the at least one first outer link chamfer is provided on the first outer link surface. With a bicycle chain having the sixth side, the sprocket teeth can easily fit between the outer link plates, making the operation of the bicycle chain smoother when shifting gears.

In a bicycle chain having a seventh side according to the fifth side, the at least one first outer link chamfer is provided on the second outer link surface. The bicycle chain having the seventh side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain having an eighth side conforming to any one of the first to seventh sides, at least one first inner link chamfer is provided on the first inner link plate. The bicycle chain having the eighth side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain of a ninth aspect according to the eighth aspect, the bushing has a first bush inner link intersection and a second bush inner link intersection, an outer peripheral surface of the bushing and a first inner link longitudinal centerline of the first inner link plate intersect with each other at the first bush inner link intersection and the second bush inner link intersection when viewed from the first inner link axial direction, the first bush inner link intersection is located closer to the first inner link lateral centerline of the first inner link plate than the second bush inner link intersection, the first inner link lateral centerline is a line that intersects perpendicularly with the first inner link longitudinal centerline, and a first inner link reference line extends parallel to the first inner link lateral centerline and is disposed between the first bushing and the first inner link. a first inner link reference line is defined as a line passing through an inner link intersection point, a second inner link reference line is defined as a line extending parallel to the first inner link lateral centerline and passing through a first inner link end edge intersection point, and the first inner link end edge intersection point is a point where the first inner link longitudinal centerline of the first inner link plate and the first inner link end edge of the first inner link end portion of the first inner link plate intersect with each other when viewed from the first inner link axial direction, and the at least one first inner link chamfered portion is provided on the first inner link plate so as to be at least partially positioned between the first inner link reference line and the second inner link reference line in the first inner link longitudinal direction relative to the first inner link longitudinal centerline of the first inner link plate.
According to the bicycle chain of the ninth aspect, contact between at least one of the inner link plates and rollers and the inner link plates and outer link plates is reduced when the bicycle chain is bent, thereby allowing the bicycle chain to operate more smoothly when changing gears.

In a bicycle chain having a tenth side conforming to any one of the first to ninth sides, at least one second outer link chamfer is provided on the second outer link plate. The bicycle chain having the tenth side allows smoother operation of the bicycle chain when shifting gears. Furthermore, the drive noise when the bicycle chain is driven is reduced.

In a bicycle chain having an eleventh side conforming to any one of the first to tenth sides, at least one second inner link chamfer is provided on the second inner link plate. The bicycle chain having the eleventh side allows smoother operation of the bicycle chain when shifting gears.

A bicycle chain according to a twelfth aspect of the present disclosure includes a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a bush, and a pin, and the first inner link plate includes a first inner link end portion including a first inner link hole having a first inner link central axis, a second inner link end portion including a second inner link hole having a second inner link central axis extending parallel to the first inner link central axis, a first inner link middle portion connecting the first inner link end portion and the second inner link end portion, a first inner link surface, and the and a second inner link surface disposed on the opposite side of the first inner link surface in a first inner link axial direction relative to a first inner link central axis, the second inner link plate including a third inner link end portion including a third inner link hole having a third inner link central axis, a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis, a second inner link intermediate portion connecting the third inner link end portion and the fourth inner link end portion, and a second inner link surface disposed on the opposite side of the first inner link surface in a first inner link axial direction relative to a first inner link central axis, the second inner link plate including a third inner link end portion including a third inner link hole having a third inner link central axis, a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis, a a third inner link surface configured to face the first inner link surface of an inner link plate, and a fourth inner link surface disposed on the opposite side of the third inner link surface in a second inner link axial direction relative to the third inner link central axis, the first outer link plate being configured to be adjacent to the first inner link plate in an assembled state of the bicycle chain so as not to sandwich another inner link plate or another outer link plate therebetween, a first outer link end portion including a first outer link hole having a first outer link central axis, and a second outer link surface extending parallel to the first outer link central axis. a second outer link end portion including a second outer link hole having a second outer link central axis, a first outer link intermediate portion connecting the first outer link end portion and the second outer link end portion, a first outer link surface, and a second outer link surface disposed on the opposite side of the first outer link surface in a first outer link axial direction relative to the first outer link central axis, the second outer link plate being configured to be adjacent to the second inner link plate in the assembled state without sandwiching another inner link plate or another outer link plate therebetween, and having a third outer link central axis a third outer link end portion including a third outer link hole; a fourth outer link end portion including a fourth outer link hole having a fourth outer link central axis extending parallel to the third outer link central axis; a second outer link intermediate portion connecting the third outer link end portion and the fourth outer link end portion; a third outer link surface configured to face the first outer link surface of the first outer link plate in the first outer link axial direction in an assembled state of the bicycle chain; and a second outer link intermediate portion disposed on the opposite side of the third outer link surface in the second outer link axial direction relative to the third outer link central axis. a fourth outer link surface that is spaced apart from the first inner link surface and that is spaced apart from the second inner link surface, the bushing has a bushing hole and is configured to be inserted into the first inner link hole and the third inner link hole when the bicycle chain is in an assembled state, the bushing has a first bushing inner link intersection and a second bushing inner link intersection, an outer peripheral surface of the bushing and a first inner link longitudinal centerline of the first inner link plate intersect with each other at the first bushing inner link intersection and the second bushing inner link intersection when viewed in the first inner link axial direction, the first bushing inner link intersection being closer to the first inner link surface than the second bushing inner link intersection a first inner link reference line extending parallel to the first inner link lateral centerline and passing through the first bush-inner link intersection point; a second inner link reference line extending parallel to the first inner link lateral centerline and passing through the first bush-inner link intersection point; a first inner link reference line extending parallel to the first inner link lateral centerline and passing through the first bush-inner link intersection point; a second inner link reference line extending parallel to the first inner link lateral centerline and passing through the first bush-inner link intersection point; The first inner link end edge intersection is defined as a line passing through the first inner link longitudinal center line of the first inner link plate and the first inner link end edge of the first inner link end portion of the first inner link plate when viewed from the first inner link axial direction, and at least one first inner link chamfer is provided on the first inner link plate so as to be at least partially disposed between the first inner link reference line and the second inner link reference line in the first inner link longitudinal direction relative to the first inner link longitudinal center line of the first inner link plate. According to the bicycle chain of the 12th side, since the pin is inserted into the bush, the bicycle chain has high rigidity, wear of the bicycle chain is suppressed, and the first inner link chamfer makes the operation of the bicycle chain smooth when shifting gears. Furthermore, the driving noise when the bicycle chain is driven is reduced.

In a bicycle chain having a 13th side that follows the 12th side, the at least one first inner link chamfer is provided on the first inner link surface. The bicycle chain having the 13th side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain having a 14th side conforming to the 12th or 13th side, the at least one first inner link chamfered portion is provided on the end portion of the second inner link. The bicycle chain having the 14th side allows smooth operation of the bicycle chain when shifting gears.

In a bicycle chain having a 15th side according to the 14th side, the at least one first inner link chamfer is provided on the first inner link surface. The bicycle chain having the 15th side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain having a 16th side conforming to any one of the 12th to 15th sides, the at least one first inner link chamfered portion is provided in the middle portion of the first inner link. The bicycle chain having the 16th side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain having a 17th side that follows the 16th side, the at least one first inner link chamfer is provided on the first inner link surface. With a bicycle chain having the 17th side, the sprocket teeth can easily fit between the inner link plates, making the operation of the bicycle chain smoother when shifting gears.

In a bicycle chain having an 18th side that follows the 16th side, the at least one first inner link chamfer is provided on the second inner link surface. The bicycle chain having the 18th side allows smoother operation of the bicycle chain when shifting gears.

In a bicycle chain having a 19th side conforming to any one of the 12th to 18th sides, at least one first outer link chamfer is provided on the first outer link plate. The bicycle chain having the 19th side allows the bicycle chain to operate smoothly when shifting gears. Furthermore, the drive noise when the bicycle chain is driven is reduced.

In a bicycle chain having a 20th side in accordance with any one of the 12th to 19th sides, at least one second outer link chamfer is provided on the second outer link plate. The bicycle chain having the 20th side allows smoother operation of the bicycle chain when shifting gears. Furthermore, the drive noise when the bicycle chain is driven is reduced.

In a bicycle chain having a 21st side in accordance with any one of the 12th to 20th sides, at least one second inner link chamfer is provided on the second inner link plate. The bicycle chain having the 21st side allows smoother operation of the bicycle chain when shifting gears.

A bicycle chain according to the twenty-second aspect of the present disclosure includes a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a bushing, a pin, a metal retaining member, and a resin member, the first inner link plate including a first inner link end portion including a first inner link hole having a first inner link central axis, a second inner link end portion including a second inner link hole having a second inner link central axis extending parallel to the first inner link central axis, a first inner link intermediate portion connecting the first inner link end portion and the second inner link end portion, a first inner link surface, and a second inner link surface arranged on the opposite side of the first inner link surface in the first inner link axial direction relative to the first inner link central axis, the second inner link plate including a third inner link end portion including a third inner link hole having a third inner link central axis, a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis; a second inner link intermediate portion connecting the third inner link end portion and the fourth inner link end portion; a third inner link surface configured to face the first inner link surface of the first inner link plate in the first inner link axial direction in an assembled state of the bicycle chain; and a fourth inner link surface disposed on the opposite side of the third inner link surface in the second inner link axial direction relative to the third inner link central axis, the first outer link plate being configured to be adjacent to the first inner link plate in the assembled state of the bicycle chain without sandwiching another inner link plate or another outer link plate therebetween; a second outer link end portion including a second outer link hole having a second outer link central axis extending parallel to the first outer link central axis, a first outer link intermediate portion connecting the first outer link end portion and the second outer link end portion, a first outer link surface, and a second outer link surface disposed on the opposite side of the first outer link surface in a first outer link axial direction relative to the first outer link central axis, the second outer link plate being configured to be adjacent to the second inner link plate in the assembled state so as not to sandwich another inner link plate or another outer link plate therebetween, a third outer link end portion including a third outer link hole having a third outer link central axis, and a fourth outer link end portion including a fourth outer link hole having a fourth outer link central axis extending parallel to the third outer link central axis, and connecting the third outer link end portion and the fourth outer link end portion. The bicycle chain includes a second outer link intermediate portion, a third outer link surface configured to face the first outer link surface of the first outer link plate in the first outer link axial direction in the assembled state of the bicycle chain, and a fourth outer link surface arranged on the opposite side of the third outer link surface in the second outer link axial direction relative to the third outer link central axis, the bush has an inner circumferential surface that constitutes a bush hole, the bush is configured to be inserted into the first inner link hole and the third inner link hole in the assembled state of the bicycle chain, the pin has an outer circumferential surface, and is configured to be inserted into the first outer link hole and the third outer link hole and pass through the bush hole in the assembled state of the bicycle chain, the metal retaining member is arranged on one of the inner circumferential surface of the bush and the outer circumferential surface of the pin, the metal retaining member includes a plurality of retaining holes, and the resin member is arranged in the plurality of retaining holes. According to the bicycle chain of the 22nd side, friction between the bush and the pin can be reduced, and the driving efficiency when the bicycle chain is driven is improved.

In a bicycle chain having a 23rd side that follows the 22nd side, the metal retaining member is disposed on the inner circumferential surface of the bush. The bicycle chain having the 23rd side reduces friction between the bush and the pin.

In the bicycle chain of the 24th aspect according to the 22nd or 23rd aspect, the bushing is formed of a first material, and the metal retaining member is formed of the first material. According to the bicycle chain of the 24th aspect, the bushing and the metal retaining member are made of the same material, so that the bushing and the metal retaining member can be firmly bonded to each other.

In the bicycle chain of aspect 25 according to aspect 22 or 23, the bushing is made of a first material, and the metal retaining member is made of a second material different from the first material. The bicycle chain of aspect 25 allows for greater freedom in the combination of the bushing material and the metal retaining member material.

A bicycle chain according to a twenty-sixth aspect of the present disclosure includes a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a bush, and a pin, the first inner link plate including a first inner link end portion including a first inner link hole having a first inner link central axis, a second inner link end portion including a second inner link hole having a second inner link central axis extending parallel to the first inner link central axis, a first inner link intermediate portion connecting the first inner link end portion and the second inner link end portion, a first inner link face, and a second inner link face disposed on the opposite side of the first inner link face in the first inner link axial direction relative to the first inner link central axis, the second inner link plate including a third inner link end portion including a third inner link hole having a third inner link central axis, and a fourth inner link central axis extending parallel to the third inner link central axis. a fourth inner link end portion including a fourth inner link hole having a first outer link central axis; a second inner link intermediate portion connecting the third inner link end portion and the fourth inner link end portion; a third inner link face configured to face the first inner link face of the first inner link plate in the first inner link axial direction in an assembled state of the bicycle chain; and a fourth inner link face disposed on the opposite side of the third inner link face in the second inner link axial direction relative to the third inner link central axis, the first outer link plate being configured to be adjacent to the first inner link plate in an assembled state of the bicycle chain so as not to sandwich another inner link plate or another outer link plate therebetween; a first outer link end portion including a first outer link hole having a first outer link central axis; a first outer link intermediate portion connecting the first outer link end portion and the second outer link end portion, a first outer link surface, and a second outer link surface arranged on the opposite side of the first outer link surface in a first outer link axial direction relative to the first outer link central axis, wherein the second outer link plate is configured to be adjacent to the second inner link plate in the assembled state so as not to sandwich another inner link plate or another outer link plate therebetween, a third outer link end portion including a third outer link hole having a third outer link central axis, a fourth outer link end portion including a fourth outer link hole having a fourth outer link central axis extending parallel to the third outer link central axis, a second outer link intermediate portion connecting the third outer link end portion and the fourth outer link end portion, and wherein the first outer link of the first outer link plate in the first outer link axial direction in the assembled state of the bicycle chain is configured to be adjacent to the second inner link plate in the assembled state so as not to sandwich another inner link plate or another outer link plate therebetween, The bicycle chain includes a third outer link surface configured to face the third outer link surface and a fourth outer link surface arranged on the opposite side of the third outer link surface in the second outer link axial direction relative to the third outer link central axis, the bush has a bush hole, a first bush end portion, and a second bush end portion arranged on the opposite side of the first bush end portion in the bush axial direction relative to the bush central axis of the bush, the bush is configured to be inserted into the first inner link hole and the third inner link hole by press-fitting when the bicycle chain is assembled, the bush includes at least one of a first radial protrusion extending radially outward from the first bush end portion relative to the bush central axis and a second radial protrusion extending radially outward from the second bush end portion relative to the bush central axis, and the pin is configured to be inserted into the first outer link hole and the third outer link hole and pass through the bush hole when the bicycle chain is assembled. According to the bicycle chain of the 26th side, the bush can be firmly fixed to the inner link plate.

In the bicycle chain of the 27th side according to the 26th side, the bushing includes the first radial protrusion and the second radial protrusion. With the bicycle chain of the 27th side, the bushing can be firmly fixed to the inner link plate.

In the bicycle chain of the 28th side according to the 26th or 27th side, the first radial protrusion has an annular shape. With the bicycle chain of the 28th side, the bushing can be more firmly fixed to the inner link plate.

In a bicycle chain having a 29th side in accordance with any one of the 26th to 28th sides, the second radial protrusion has an annular shape. With the bicycle chain having the 29th side, the bushing can be more firmly fixed to the inner link plate.

In a bicycle chain according to any one of the 26th to 29th sides, the first radial protrusion is formed by crimping. With the bicycle chain according to the 30th side, the bushing can be efficiently fixed to the inner link plate.

In a bicycle chain having a 31st side in accordance with any one of the 26th to 30th sides, the second radial protrusion is formed by crimping. With the bicycle chain having the 31st side, the bushing can be efficiently fixed to the inner link plate.

In a bicycle chain according to any one of the 26th to 31st sides, the pin is inserted into the first outer link hole and the third outer link hole by press-fitting. With the bicycle chain according to the 32nd side, the pin can be efficiently fixed to the outer link plate.

The bicycle chain disclosed herein allows for smoother operation of the bicycle chain when shifting gears.

A schematic diagram of a bicycle, seen from above. 1 is a perspective view of a portion of a bicycle chain according to a first embodiment; 3 is a cross-sectional view of the bicycle chain of the first embodiment taken along line III-III in FIG. 2. FIG. 3 is a side view of the bicycle chain of the first embodiment as seen from the VA direction in FIG. 2 . FIG. 3 is a side view of the bicycle chain of the first embodiment as viewed from the VB direction of FIG. 2 . 6 is a cross-sectional view of the bicycle chain of the first embodiment taken along line VI-VI in FIG. 3. 7 is a cross-sectional view of the bicycle chain of the first embodiment taken along line VII-VII in FIG. 3. FIG. 3 is a side view of the bicycle chain of the first embodiment as seen from the VA direction in FIG. 2 . 9 is a cross-sectional view of the bicycle chain of the first embodiment taken along line IX-IX in FIG. 3. 13A and 13B are a perspective view and a partially enlarged view of a bushing of a bicycle chain according to a third embodiment, the perspective view being cut along a plane including the central axis of the bushing; 1 is a cross-sectional view of a bushing cut along a plane perpendicular to the central axis of the bushing. 4A and 4B are perspective and enlarged partial views of a pin. A cross-sectional view of a pin cut by a plane perpendicular to the central axis of the pin. FIG. 10 is a cross-sectional view of a bicycle chain according to a fourth embodiment. FIG. 11 is a perspective view of a bushing for a bicycle chain according to a fourth embodiment, taken along a plane including the central axis of the bushing. FIG. 11 is a cross-sectional view of a bicycle chain according to another embodiment.

First Embodiment
With reference to FIG. 1, a human-powered vehicle to which a bicycle chain is applied will be described.
FIG. 1 shows a top view of a bicycle A, which is an example of a human-powered vehicle. Here, a human-powered vehicle means a vehicle that uses human power at least in part as a driving force for traveling, and includes vehicles that electrically assisted human power. Vehicles that use only a driving force other than human power are not included in human-powered vehicles. In particular, vehicles that use only an internal combustion engine as a driving force are not included in human-powered vehicles. Typically, human-powered vehicles are assumed to be small and light vehicles, and vehicles that do not require a license to be driven on public roads are assumed. The human-powered vehicle shown in the figure includes bicycle A. Specifically, the human-powered vehicle is bicycle A. Bicycle A includes a drive train B.

Drivetrain B is a chain drive type. Drivetrain B includes bicycle crank assembly C, a bicycle sprocket (hereinafter referred to as "sprocket D"), and bicycle chain 10. Sprocket D has sprocket teeth with which bicycle chain 10 engages. Sprocket D includes a front sprocket E and a rear sprocket F. Bicycle crank assembly C includes crankshaft Ca, which is rotatably supported on the frame of bicycle A, and a pair of crank arms Cb, each provided at both ends of crankshaft Ca. Pedals are rotatably attached to the tip of each crank arm Cb.

The front sprocket E is attached to the crankshaft Ca so as to rotate integrally with the crankshaft Ca. The rear sprocket F is attached to the hub of the rear wheel. The bicycle chain 10 is wound around the front sprocket E and the rear sprocket F. The driving force applied to the pedals by a user riding bicycle A is transmitted to the rear wheel via the front sprocket E, the bicycle chain 10, and the rear sprocket F.

The bicycle chain 10 will be described with reference to Figures 2 to 9. In Figure 3, the first inner link plate 12 and the second inner link plate 14 connected to the right side, and the additional roller 28 are shown in phantom lines. Also, in Figure 3, the first outer link plate 16 and the second outer link plate 18 connected to the left side, and the additional pin 23 are shown in phantom lines. Figure 6 is a cross-sectional view of the bicycle chain 10 including the first inner link plate 12 and the first outer link plate 16, taken along line VI-VI in Figure 3, with the roller 24 and the additional roller 28 omitted in this figure. Figure 7 is a cross-sectional view of the bicycle chain 10 including the second inner link plate 14 and the second outer link plate 18, taken along line VII-VII in Figure 3, with the roller 24 and the additional roller 28 omitted in this figure. Figure 8 is the same view as Figure 4. Figure 9 is the same view as Figure 6.

As shown in FIG. 2, the bicycle chain 10 includes a first inner link plate 12, a second inner link plate 14, a first outer link plate 16, a second outer link plate 18, a bushing 20, and a pin 22. More preferably, the bicycle chain 10 includes a roller 24.

As shown in FIG. 3, the first inner link plate 12 includes a first inner link end portion 32 including a first inner link hole 30 having a first inner link central axis AX1, a second inner link end portion 36 including a second inner link hole 34 having a second inner link central axis AX2 extending parallel to the first inner link central axis AX1, and a first inner link intermediate portion 38 connecting the first inner link end portion 32 and the second inner link end portion 36. The first inner link plate 12 further includes a first inner link surface 12A and a second inner link surface 12B disposed on the opposite side of the first inner link surface 12A in the first inner link axial direction DA relative to the first inner link central axis AX1.

As shown in FIG. 4, the first inner link plate 12 has a first inner link longitudinal centerline LCA and a first inner link lateral centerline LCB perpendicular to the first inner link longitudinal centerline LCA. The first inner link distance LGA is defined between the first inner link central axis AX1 and the second inner link central axis AX2 in the first inner link longitudinal direction DE relative to the first inner link longitudinal centerline LCA.

In this embodiment, the first inner link longitudinal centerline LCA and the first inner link lateral centerline LCB are defined based on the first inner link plate 12 .
4, the first inner link longitudinal centerline LCA is defined as a line extending along the longitudinal direction of the first inner link plate 12 when the first inner link plate 12 is viewed in a direction along the first inner link axial direction DA, and passing through the first inner link central axis AX1 and the second inner link central axis AX2. The first inner link lateral centerline LCB is defined as a line intersecting the first inner link longitudinal centerline LCA perpendicularly, and passing through the midpoint between the first inner link central axis AX1 and the second inner link central axis AX2.

As shown in FIG. 3, the second inner link plate 14 includes a third inner link end portion 42 including a third inner link hole 40 having a third inner link central axis AX3, a fourth inner link end portion 46 including a fourth inner link hole 44 having a fourth inner link central axis AX4 extending parallel to the third inner link central axis AX3, and a second inner link intermediate portion 48 connecting the third inner link end portion 42 and the fourth inner link end portion 46. The second inner link plate 14 includes a third inner link surface 14A configured to face the first inner link surface 12A of the first inner link plate 12 in the first inner link axial direction DA in the assembled state of the bicycle chain 10, and a fourth inner link surface 14B arranged on the opposite side of the third inner link surface 14A in the second inner link axial direction DB with respect to the third inner link central axis AX3.

As shown in FIG. 5, the second inner link plate 14 has a second inner link longitudinal centerline LCC and a second inner link lateral centerline LCD perpendicular to the second inner link longitudinal centerline LCC. The second inner link distance LGB is defined between the third inner link central axis AX3 and the fourth inner link central axis AX4 in the second inner link longitudinal direction DF with respect to the second inner link longitudinal centerline LCC. Preferably, each of the first inner link distance LGA and the second inner link distance LGB is in the range of 9 mm to 13 mm. For example, each of the first inner link distance LGA and the second inner link distance LGB is set to 12.7 mm or 10 mm.

In this embodiment, the second inner link longitudinal centerline LCC and the second inner link lateral centerline LCD are defined based on the second inner link plate 14 .
5, the second inner link longitudinal centerline LCC is defined as a line extending along the longitudinal direction of the second inner link plate 14 when the second inner link plate 14 is viewed in a direction along the second inner link axial direction DB, and passing through the third inner link central axis AX3 and the fourth inner link central axis AX4. The second inner link lateral centerline LCD is defined as a line intersecting the second inner link longitudinal centerline LCC perpendicularly, and passing through the midpoint between the third inner link central axis AX3 and the fourth inner link central axis AX4.

As shown in FIG. 3, the first outer link plate 16 is configured to be adjacent to the first inner link plate 12 without any other inner link plate or other outer link plate in the assembled state of the bicycle chain 10. The first outer link plate 16 includes a first outer link end portion 52 including a first outer link hole 50 having a first outer link central axis BX1, a second outer link end portion 56 including a second outer link hole 54 having a second outer link central axis BX2 extending parallel to the first outer link central axis BX1, and a first outer link intermediate portion 58 connecting the first outer link end portion 52 and the second outer link end portion 56. The first outer link plate 16 includes a first outer link surface 16A and a second outer link surface 16B arranged on the opposite side of the first outer link surface 16A in the first outer link axial direction DC relative to the first outer link central axis BX1.

As shown in FIG. 4, the first outer link plate 16 has a first outer link longitudinal centerline LCE and a first outer link lateral centerline LCF perpendicular to the first outer link longitudinal centerline LCE. The first outer link distance LGC is defined between the first outer link central axis BX1 and the second outer link central axis BX2 in the first outer link longitudinal direction DG relative to the first outer link longitudinal centerline LCE.

In this embodiment, a first outer link longitudinal centerline LCE and a first outer link lateral centerline LCF are defined based on the first outer link plate 16 .
4, the first outer link longitudinal centerline LCE is defined as a line extending along the longitudinal direction of the first outer link plate 16 when the first outer link plate 16 is viewed in a direction along the first outer link axial direction DC, and passing through the first outer link central axis BX1 and the second outer link central axis BX2. The first outer link lateral centerline LCF is defined as a line intersecting the first outer link longitudinal centerline LCE perpendicularly, and passing through the midpoint between the first outer link central axis BX1 and the second outer link central axis BX2.

3, the second outer link plate 18 is configured to be adjacent to the second inner link plate 14 without any other inner link plate or other outer link plate in the assembled state of the bicycle chain 10. The second outer link plate 18 includes a third outer link end portion 62 including a third outer link hole 60 having a third outer link central axis BX3, a fourth outer link end portion 66 including a fourth outer link hole 64 having a fourth outer link central axis BX4 extending parallel to the third outer link central axis BX3, and a second outer link intermediate portion 68 connecting the third outer link end portion 62 and the fourth outer link end portion 66. The second outer link plate 18 includes a third outer link surface 18A that is configured to face the first outer link surface 16A of the first outer link plate 16 in the first outer link axial direction DC when the bicycle chain 10 is in an assembled state, and a fourth outer link surface 18B that is positioned on the opposite side of the third outer link surface 18A in the second outer link axial direction DD relative to the third outer link central axis BX3.

As shown in FIG. 5, the second outer link plate 18 has a second outer link longitudinal centerline LCG and a second outer link lateral centerline LCH perpendicular to the second outer link longitudinal centerline LCG. The second outer link distance LGD is defined between the third outer link central axis BX3 and the fourth outer link central axis BX4 in the second outer link longitudinal direction DH relative to the second outer link longitudinal centerline LCG. Preferably, each of the first outer link distance LGC and the second outer link distance LGD is in the range of 9 mm to 13 mm. For example, each of the first outer link distance LGC and the second outer link distance LGD is set to 12.7 mm or 10 mm.

In this embodiment, second outer link longitudinal centerline LCG and second outer link lateral centerline LCH are defined based on second outer link plate 18.
5, the second outer link longitudinal centerline LCG is defined as a line extending along the longitudinal direction of the second outer link plate 18 when the second outer link plate 18 is viewed in a direction along the second outer link axis direction DD, and passing through the third outer link central axis BX3 and the fourth outer link central axis BX4. The second outer link lateral centerline LCH is defined as a line intersecting the second outer link longitudinal centerline LCG perpendicularly, and passing through the midpoint between the third outer link central axis BX3 and the fourth outer link central axis BX4.

3, the bushing 20 has a bushing hole 20A. The bushing 20 is configured to be inserted into the first inner link hole 30 and the third inner link hole 40 when the bicycle chain 10 is in an assembled state.
The additional bushing 26, which is separate from the bushing 20 inserted into the first inner link hole 30 and the third inner link hole 40, has an additional bushing hole 26A. The additional bushing 26 is configured to be inserted into the second inner link hole 34 and the fourth inner link hole 44 when the bicycle chain 10 is in an assembled state.

As shown in FIG. 8, the bush 20 has a first bush outer link intersection SA1 and a second bush outer link intersection SA2. The outer peripheral surface 20B of the bush 20 and the first outer link longitudinal centerline LCE of the first outer link plate 16 intersect with each other at the first bush outer link intersection SA1 and the second bush outer link intersection SA2 when viewed from the first outer link axial direction DC. The first bush outer link intersection SA1 is located closer to the first outer link lateral centerline LCF of the first outer link plate 16 than the second bush outer link intersection SA2. The first outer link lateral centerline LCF is a line that intersects perpendicularly with the first outer link longitudinal centerline LCE.

9, the bush 20 has a first bush inner link intersection point SB1 and a second bush inner link intersection point SB2. The outer peripheral surface 20B of the bush 20 and the first inner link longitudinal centerline LCA of the first inner link plate 12 intersect with each other at the first bush inner link intersection point SB1 and the second bush inner link intersection point SB2 when viewed from the first inner link axial direction DA, and the first bush inner link intersection point SB1 is located closer to the first inner link lateral centerline LCB of the first inner link plate 12 than the second bush inner link intersection point SB2. The first inner link lateral centerline LCB is a line that intersects perpendicularly with the first inner link longitudinal centerline LCA.

As shown in FIG. 3, the pin 22 is configured to be inserted into the first outer link hole 50 and the third outer link hole 60 and pass through the bush hole 20A when the bicycle chain 10 is assembled. Preferably, the pin 22 is inserted into the first outer link hole 50 and the third outer link hole 60 by press-fitting when the bicycle chain 10 is assembled. The additional pin 23 is inserted into the second outer link hole 54 and the fourth outer link hole 64 when the bicycle chain 10 is assembled, and passes through the additional bush hole 26A of the additional bush 26. Preferably, the additional pin 23 is inserted into the second outer link hole 54 and the fourth outer link hole 64 by press-fitting when the bicycle chain 10 is assembled. Preferably, the pin 22 has a pin outer diameter of 3.6 mm or less. Furthermore, preferably, the pin outer diameter is 2.5 mm or more. Preferably, the additional pin 23 has an additional pin outer diameter of 3.6 mm or less. Preferably, the outer diameter of the additional pin is 2.5 mm or more.

The first outer link plate 16 and the second outer link plate 18 are connected by a pin 22 and an additional pin 23. The first inner link plate 12 and the second inner link plate 14 are connected by a bushing 20 and an additional bushing 26.
The combined body of the first inner link plate 12 and the second inner link plate 14 is rotatably connected to the combined body of the first outer link plate 16 and the second outer link plate 18 around the pin central axis CY1 of the pin 22 and the pin central axis CY2 of the additional pin 23.
The combined body consisting of the first inner link plate 12 and the second inner link plate 14 and the combined body consisting of the first outer link plate 16 and the second outer link plate 18 are arranged alternately and connected in the form of a loop.

As shown in FIG. 3 , the roller 24 is disposed between the first inner link plate 12 and the second inner link plate 14 .
The roller 24 has a roller hole 24A through which the bush 20 is inserted. The roller 24 is rotatable relative to the bush 20. The additional roller 28 has an additional roller hole 28A through which the additional bush 26 is inserted. The additional roller 28 is rotatable relative to the additional bush 26.

The roller 24 is disposed between the first inner link end portion 32 of the first inner link plate 12 and the third inner link end portion 42 of the second inner link plate 14. The additional roller 28 is disposed between the second inner link end portion 36 of the first inner link plate 12 and the fourth inner link end portion 46 of the second inner link plate 14. When the bicycle chain 10 is attached to bicycle A, the roller 24 and the additional roller 28 contact the sprocket teeth.

The first outer link plate 16 is provided with at least one first outer link chamfer 70 .
Referring to FIG. 8, the location where the first outer link chamfered portion 70 is provided will be described.

The first outer link reference line RA1 is defined as a line that extends parallel to the first outer link lateral centerline LCF and passes through the first bush outer link intersection point SA1. The second outer link reference line RA2 is defined as a line that extends parallel to the first outer link lateral centerline LCF and passes through the first outer link edge intersection point SC1. The first outer link edge intersection point SC1 is the point where the first outer link longitudinal centerline LCE of the first outer link plate 16 and the first outer link edge 52A of the first outer link end portion 52 of the first outer link plate 16 intersect with each other when viewed from the first outer link axial direction DC.

At least one first outer link chamfer 70 is provided on the first outer link plate 16 so as to be at least partially disposed between the first outer link reference line RA1 and the second outer link reference line RA2 in the first outer link longitudinal direction DG relative to the first outer link longitudinal centerline LCE of the first outer link plate 16.

As shown in FIG. 8, at least one first outer link chamfer 70 may be provided on the second outer link surface 16B. In the first outer link plate 16, the second outer link surface 16B between the first outer link reference line RA1 and the second outer link reference line RA2 frequently comes into contact with the sprocket D of the bicycle A. By providing the first outer link chamfer 70 between the first outer link reference line RA1 and the second outer link reference line RA2, interference between the sprocket D and the first outer link plate 16 during gear shifting is reduced, and the operation of the bicycle chain 10 during gear shifting is smoother.

At least one first outer link chamfer 70 may be provided on the second outer link end portion 56. At least one first outer link chamfer 70 may be provided on the second outer link surface 16B at the second outer link end portion 56. This configuration reduces interference between the sprocket D and the first outer link plate 16, allowing the bicycle chain 10 to operate smoothly when shifting gears.

As shown in FIG. 6, at least one first outer link chamfer 70 may be provided on the first outer link intermediate portion 58. At least one first outer link chamfer 70 may be provided on the first outer link surface 16A at the first outer link intermediate portion 58. This configuration makes it easier for the sprocket teeth to enter between the first outer link plate 16 and the second outer link plate 18. At least one first outer link chamfer 70 may be provided on the second outer link surface 16B at the first outer link intermediate portion 58.

As shown in FIG. 9, at least one first inner link chamfer 72 may be provided on the first inner link plate 12. The location where the first inner link chamfer 72 is provided will be described.

The first inner link reference line RB1 is defined as a line that extends parallel to the first inner link lateral centerline LCB and passes through the first bush inner link intersection point SB1. The second inner link reference line RB2 is defined as a line that extends parallel to the first inner link lateral centerline LCB and passes through the first inner link edge intersection point SD1. The first inner link edge intersection point SD1 is the point where the first inner link longitudinal centerline LCA of the first inner link plate 12 and the first inner link edge 32A of the first inner link end portion 32 of the first inner link plate 12 intersect with each other when viewed from the first inner link axial direction DA.

At least one first inner link chamfer 72 may be provided on the first inner link plate 12 so as to be at least partially disposed between the first inner link reference line RB1 and the second inner link reference line RB2 in the first inner link longitudinal direction DE relative to the first inner link longitudinal centerline LCA of the first inner link plate 12.

For example, the first inner link chamfered portion 72 is provided on the first inner link surface 12A at the first inner link end portion 32. The first inner link chamfered portion 72 is provided on the first inner link surface 12A at the second inner link end portion 36. When the bicycle chain 10 bends during gear shifting, the first inner link chamfered portion 72 is provided on the first inner link surface 12A at the first inner link end portion 32, thereby reducing the possibility of the bicycle chain 10 coming off the sprocket D of the bicycle A at an undesirable time. Similarly, when the bicycle chain 10 bends during gear shifting, the first inner link chamfered portion 72 is provided on the first inner link surface 12A at the second inner link end portion 36, thereby reducing the possibility of the bicycle chain 10 coming off the sprocket D of the bicycle A at an undesirable time. In this way, the operation of the bicycle chain 10 during gear shifting is smoothed.

As shown in FIG. 5, at least one second outer link chamfer 74 may be provided on the second outer link plate 18. At least one second outer link chamfer 74 may be disposed on the fourth outer link surface 18B at the third outer link end portion 62. At least one second outer link chamfer 74 may be disposed on the fourth outer link surface 18B at the fourth outer link end portion 66. This configuration reduces interference between the sprocket D and the second outer link plate 18 during gear shifting, allowing the bicycle chain 10 to operate smoothly during gear shifting.

As shown in FIG. 7, at least one second inner link chamfer 76 may be provided on the second inner link plate 14. At least one second inner link chamfer 76 is provided on the third inner link surface 14A at the third inner link end portion 42. The second inner link chamfer 76 is provided on the third inner link surface 14A at the fourth inner link end portion 46. This reduces the possibility of the bicycle chain 10 coming off the sprocket D of the bicycle A at an undesirable time. In this way, the operation of the bicycle chain 10 during gear shifting is smoother.

Second Embodiment
A bicycle chain 10 of the second embodiment will be described. The same reference numerals as in the first embodiment are used for the components common to the first embodiment, and duplicated explanations will be omitted. The bicycle chain 10 of the second embodiment has at least a first inner link chamfered portion 72, and preferably also has a first outer link chamfered portion 70.

At least one first inner link chamfer 72 is provided on the first inner link end portion 32 of the first inner link plate 12. Specifically, as shown in FIG. 9, at least one first inner link chamfer 72 is provided on the first inner link plate 12 so as to be at least partially disposed between the first inner link reference line RB1 and the second inner link reference line RB2 in the first inner link longitudinal direction DE relative to the first inner link longitudinal centerline LCA of the first inner link plate 12.

As shown in FIG. 6, at least one first inner link chamfer 72 may be provided on the first inner link surface 12A. At least one first inner link chamfer 72 may be provided on the second inner link end portion 36. At least one first inner link chamfer 72 may be provided on the first inner link surface 12A at the second inner link end portion 36. By providing the first inner link chamfer 72 on the first inner link surface 12A, it becomes easier to maintain engagement between the bicycle chain 10 and the sprocket D when the bicycle chain 10 is shifting gears. This allows the bicycle chain 10 to operate smoothly when shifting gears.

At least one first inner link chamfer 72 may be provided on the first inner link intermediate portion 38. At least one first inner link chamfer 72 may be provided on the first inner link surface 12A at the first inner link intermediate portion 38. This configuration makes it easier for the sprocket teeth to enter between the first inner link plate 12 and the second inner link plate 14. At least one first inner link chamfer 72 may be provided on the second inner link surface 12B at the first inner link intermediate portion 38.

As shown in FIG. 4, at least one first outer link chamfer 70 may be provided on the first outer link plate 16. At least one first outer link chamfer 70 may be disposed on the second outer link surface 16B at the first outer link end portion 52. At least one first outer link chamfer 70 may be disposed on the second outer link surface 16B at the second outer link end portion 56. This configuration reduces interference between the sprocket D and the first outer link plate 16 during gear shifting, thereby smoothing the operation of the bicycle chain 10 during gear shifting.

As shown in FIG. 5, at least one second outer link chamfer 74 may be provided on the second outer link plate 18. At least one second outer link chamfer 74 may be disposed on the fourth outer link surface 18B at the third outer link end portion 62. At least one second outer link chamfer 74 may be disposed on the fourth outer link surface 18B at the fourth outer link end portion 66. This configuration reduces interference between the sprocket D and the second outer link plate 18 during gear shifting, allowing the bicycle chain 10 to operate smoothly during gear shifting.

As shown in FIG. 7, at least one second inner link chamfer 76 may be provided on the second inner link plate 14. The second inner link chamfer 76 is provided on the third inner link surface 14A at the third inner link end portion 42. The second inner link chamfer 76 is provided on the third inner link surface 14A at the fourth inner link end portion 46. By providing the second inner link chamfer 76 on the third inner link surface 14A, it becomes easier to maintain engagement between the bicycle chain 10 and the sprocket D when shifting gears of the bicycle chain 10. In this way, the operation of the bicycle chain 10 becomes smoother when shifting gears.

Third Embodiment
A bicycle chain 10 of the third embodiment will be described with reference to Figures 10 to 13. Components common to the third embodiment are given the same reference numerals as the first embodiment, and duplicated descriptions will be omitted. In the bicycle chain 10 of the third embodiment, the structure of the bushing 20 differs from that of the bicycle chain 10 of the first embodiment. In the bicycle chain 10 of the third embodiment, at least one of the first outer link chamfered portion 70, the first inner link chamfered portion 72, the second outer link chamfered portion 74, and the second inner link chamfered portion 76 shown in the first embodiment may be omitted.

The bushing 20 has an inner circumferential surface 20C that defines the bushing hole 20A. The bushing 20 is configured to be inserted into the first inner link hole 30 and the third inner link hole 40 when the bicycle chain 10 is in an assembled state.

The pin 22 has an outer circumferential surface 22A, and is configured to be inserted through the first outer link hole 50 and the third outer link hole 60 and pass through the bush hole 20A when the bicycle chain 10 is in an assembled state.

In this embodiment, a metal retaining member 80 is provided between the bush 20 and the pin 22. The metal retaining member 80 is disposed on one of the inner peripheral surface 20C of the bush 20 and the outer peripheral surface 22A of the pin 22. The metal retaining member 80 includes a plurality of retaining holes 80A. Resin members 82 are disposed in the plurality of retaining holes 80A. The resin members 82 are disposed so as to be exposed on at least one of the inner peripheral surface and the outer peripheral surface of the metal retaining member 80. The retaining holes 80A include through holes, depressions, and grooves. When the retaining holes 80A are configured as grooves, the retaining holes 80A may be in a mesh shape, a linear structure, or a spiral shape.

For example, as shown in FIG. 10 and FIG. 11, the metal retaining member 80 is disposed on the inner peripheral surface 20C of the bushing 20. The metal retaining member 80 has a cylindrical shape with the bushing central axis CX of the bushing 20 as its central axis. Preferably, the inner peripheral surface of the metal retaining member 80 and the inner peripheral surface of the resin member 82 are configured to be flush with each other. The resin member 82 is disposed so as to be exposed on the inner peripheral surface of the metal retaining member 80. The resin member 82 may be an abrasion-resistant resin. Examples of the resin member 82 include phenolic resin and polyacetal resin.

The bushing 20 may be formed of a first material, and the metal retaining member 80 may be formed of the first material. The bushing 20 may be formed of a first material, and the metal retaining member 80 may be formed of a second material different from the first material. The first material includes a metal. Examples of the first material include iron, an aluminum alloy, stainless steel, and a titanium alloy. The second material includes a metal.

The additional bushing 26 is configured to be inserted into the second inner link hole 34 and the fourth inner link hole 44 when the bicycle chain 10 is in an assembled state. The additional bushing 26 may have the same structure as the bushing 20, or may have a different structure from the bushing 20.

Also, as shown in FIG. 12 and FIG. 13, the metal holding member 84 may be disposed on the outer peripheral surface 22A of the pin 22. The metal holding member 84 has a cylindrical shape with the pin central axis CY1 of the pin 22 as its central axis. The metal holding member 84 includes a plurality of holding holes 84A. The resin member 86 is disposed in the plurality of holding holes 84A. The resin member 86 is disposed so as to be exposed on the outer peripheral surface of the metal holding member 80.

The pin 22 may be formed of a third material, and the metal retaining member 84 may be formed of the third material. The pin 22 may be formed of a third material, and the metal retaining member 84 may be formed of a fourth material different from the third material. The third material includes a metal. Examples of the third material include iron, an aluminum alloy, stainless steel, and a titanium alloy. The fourth material includes a metal. Preferably, the additional pin 23 has a structure similar to that of the pin 22.

Fourth Embodiment
A bicycle chain 10 of the fourth embodiment will be described with reference to Figures 14 and 15. Configurations common to the fourth embodiment are given the same reference numerals as the first embodiment, and duplicated descriptions will be omitted. The shape of the bicycle chain 10 of the fourth embodiment differs in some parts from the shape of the bicycle chain 10 of the first embodiment, but descriptions of these will be omitted. In the bicycle chain 10 of the fourth embodiment, the structure of the bushing 20 differs from that of the bicycle chain 10 of the first embodiment. In the bicycle chain 10 of the fourth embodiment, at least one of the first outer link chamfered portion 70, the first inner link chamfered portion 72, the second outer link chamfered portion 74, and the second inner link chamfered portion 76 shown in the first embodiment may be omitted.

The bushing 20 has a bushing hole 20A, a first bushing end portion 90, and a second bushing end portion 92 that is located on the opposite side of the first bushing end portion 90 in the bushing axial direction DJ relative to the bushing central axis CX of the bushing 20. The bushing 20 is configured to be inserted by press-fitting into the first inner link hole 30 and the third inner link hole 40 when the bicycle chain 10 is in an assembled state. The first bushing end portion 90 is inserted by press-fitting into the first inner link hole 30. The second bushing end portion 92 is inserted by press-fitting into the third inner link hole 40.

The bushing 20 includes at least one of a first radial protrusion 94 extending in the radially outward direction DR from a first bushing end portion 90 relative to the bushing central axis CX and a second radial protrusion 96 extending in the radially outward direction DR from a second bushing end portion 92 relative to the bushing central axis CX.

Preferably, as shown in FIG. 14, the bushing 20 includes a first radial protrusion 94 and a second radial protrusion 96. The first radial protrusion 94 has an annular shape. The second radial protrusion 96 has an annular shape. The first radial protrusion 94 is formed by crimping. The second radial protrusion 96 is formed by crimping.

The first radial protrusion 94 is formed at the boundary between the first inner link hole 30 and the second inner link surface 12B by crimping the outer periphery of the first bush end portion 90 when the first bush end portion 90 is inserted into the first inner link hole 30. The second radial protrusion 96 is formed at the boundary between the third inner link hole 40 and the fourth inner link surface 14B by crimping the outer periphery of the second bush end portion 92 when the second bush end portion 92 is inserted into the third inner link hole 40.

By inserting the bushing 20 into the first inner link hole 30 and the third inner link hole 40, and by crimping the first bushing end portion 90 and the second bushing end portion 92, the first inner link plate 12 and the second inner link plate 14 are firmly connected via the bushing 20.

The pin 22 is inserted into the first outer link hole 50 and the third outer link hole 60 by press-fitting. The pin 22 has a first pin end portion 100 and a second pin end portion 102 arranged on the opposite side of the first pin end portion 100 in the pin axis direction DK relative to the pin central axis CY1. The first pin end portion 100 is inserted into the first outer link hole 50 by press-fitting and crimped to be formed around the first outer link hole 50. The second pin end portion 102 is inserted into the third outer link hole 60 by press-fitting and crimped to be formed around the third outer link hole 60.

<Modifications>
The description of each embodiment is an example of the bicycle chain 10 according to the present disclosure, and is not intended to limit its form. The bicycle chain 10 according to the present disclosure may take the form of, for example, a modified version of the embodiment shown below, or a combination of at least two mutually non-contradictory modified versions. In the modified versions below, parts common to the embodiment will be given the same reference numerals as the embodiment, and descriptions thereof will be omitted.

A modified example of the bicycle chain 10 of the fourth embodiment will now be described with reference to FIG.
The first inner link end portion 32 includes a first annular axial protrusion 104 that circumferentially surrounds the first inner link hole 30 with respect to the first inner link central axis AX1. The first annular axial protrusion 104 protrudes toward the second inner link plate 14 in a direction along the first inner link axial direction DA when the bicycle chain 10 is in an assembled state. The third inner link end portion 42 includes a second annular axial protrusion 106 that circumferentially surrounds the third inner link hole 40 with respect to the third inner link central axis AX3. The second annular axial protrusion 106 protrudes toward the first inner link plate 12 in a direction along the second inner link axial direction DB when the bicycle chain 10 is in an assembled state.

The bushing 20 is inserted into the first inner link hole 30 and the third inner link hole 40 when the bicycle chain 10 is assembled. The first bushing end portion 90 of the bushing 20 is configured to enter and contact the first annular axial protrusion 104 when the bicycle chain 10 is assembled. The second bushing end portion 92 of the bushing 20 is configured to enter and contact the second annular axial protrusion 106 when the bicycle chain 10 is assembled.

The bushing 20 includes at least one of a first radial protrusion 94 extending in the radially outward direction DR from a first bushing end portion 90 relative to the bushing central axis CX and a second radial protrusion 96 extending in the radially outward direction DR from a second bushing end portion 92 relative to the bushing central axis CX.

The first radial protrusion 94 is formed at the boundary between the first inner link hole 30 and the second inner link surface 12B by crimping the outer periphery of the first bush end portion 90 when the first bush end portion 90 is inserted into the first annular axial protrusion 104. The second radial protrusion 96 is formed at the boundary between the third inner link hole 40 and the fourth inner link surface 14B by crimping the outer periphery of the second bush end portion 92 when the second bush end portion 92 is inserted into the second annular axial protrusion 106.

By inserting the bushing 20 into the first annular axial protrusion 104 and the second annular axial protrusion 106, crimping the first bushing end portion 90, and crimping the second bushing end portion 92, the first inner link plate 12 and the second inner link plate 14 are firmly connected via the bushing 20.

In each of the above-described embodiments and modified examples, at least one of the following items may be applied.
At least one first outer link chamfer portion 70 formed on the first outer link plate 16 may be formed to extend continuously from the first outer link end portion 52, through the first outer link intermediate portion 58, to the second outer link end portion 56 on at least one of the first outer link surface 16A and the second outer link surface 16B.
At least one second outer link chamfer portion 74 formed on the second outer link plate 18 may be formed to extend continuously from the third outer link end portion 62, through the second outer link intermediate portion 68, to the fourth outer link end portion 66 on at least one of the third outer link surface 18A and the fourth outer link surface 18B.
At least one first inner link chamfer portion 72 formed on the first inner link plate 12 may be formed to extend continuously from the first inner link end portion 32, through the first inner link intermediate portion 38, to the second inner link end portion 36 on at least one of the first inner link surface 12A and the second inner link surface 12B.
At least one second inner link chamfer portion 76 formed on the second inner link plate 14 may be formed to extend continuously from the third inner link end portion 42, through the second inner link intermediate portion 48, to the fourth inner link end portion 46 on at least one of the third inner link surface 14A and the fourth inner link surface 14B.
At least one first outer link chamfer portion 70 formed on the first outer link plate 16 may be formed to extend continuously along the entire circumference of the first outer link plate 16 on at least one of the first outer link surface 16A and the second outer link surface 16B.
At least one second outer link chamfer 74 formed on the second outer link plate 18 may be formed to extend continuously along the entire circumference of the second outer link plate 18 on at least one of the third outer link surface 18A and the fourth outer link surface 18B.
At least one first inner link chamfer portion 72 formed on the first inner link plate 12 may be formed to extend continuously along the entire circumference of the first inner link plate 12 on at least one of the first inner link surface 12A and the second inner link surface 12B.
At least one second inner link chamfer 76 formed on the second inner link plate 14 may be formed to extend continuously along the entire circumference of the second inner link plate 14 on at least one of the third inner link surface 14A and the fourth inner link surface 14B.

AX1...first inner link central axis, AX2...second inner link central axis, AX3...third inner link central axis, AX4...fourth inner link central axis, BX1...first outer link central axis, BX2...second outer link central axis, BX3...third outer link central axis, BX4...fourth outer link central axis, CX...bush central axis, LCA...first inner link longitudinal centerline, LCB...first inner link lateral centerline, LCE...first outer link longitudinal centerline, LCF...first outer link lateral centerline, RA1...first outer link reference line, RA2...second outer link reference line, RB1...first inner link reference line, RB2 ...second inner link reference line, SA1...first bush outer link intersection, SA2...second bush outer link intersection, SB1...first bush inner link intersection, SB2...second bush inner link intersection, SC1...first outer link end edge intersection, SD1...first inner link end edge intersection, 10...bicycle chain, 12...first inner link plate, 12A...first inner link surface, 12B...second inner link surface, 14...second inner link plate, 14A...third inner link surface, 14B...fourth inner link surface, 16...first outer link plate, 16A...first outer link surface, 16B...second outer link surface, 18...second outer link Plate, 18A...third outer link surface, 18B...fourth outer link surface, 20...bush, 20A...bush hole, 20B...outer peripheral surface, 20C...inner peripheral surface, 22...pin, 22A...outer peripheral surface, 26...additional bush, 26A...additional bush hole, 30...first inner link hole, 32...first inner link end portion, 34...second inner link hole, 36...second inner link end portion, 38...first inner link middle portion, 40...third inner link hole, 42...third inner link end portion, 44...fourth inner link hole, 46...fourth inner link end portion, 48...second inner link middle portion, 50...first outer link hole, 52...first outer link end portion, 54... Second outer link hole, 56...second outer link end portion, 58...first outer link middle portion, 60...third outer link hole, 62...third outer link end portion, 64...fourth outer link hole, 66...fourth outer link end portion, 68...second outer link middle portion, 70...first outer link chamfered portion, 72...first inner link chamfered portion, 74...second outer link chamfered portion, 76...second inner link chamfered portion, 80...metal retaining member, 80A...retaining hole, 82...resin member, 84...metal retaining member, 84A...retaining hole, 86...resin member, 90...first bush end portion, 92...second bush end portion, 94...first radial protrusion, 96...second radial protrusion.

Claims (10)

A bicycle chain, comprising:
a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a bush, and a pin;
The first inner link plate is
a first inner link end portion including a first inner link hole having a first inner link central axis;
a second inner link end portion including a second inner link hole having a second inner link central axis extending parallel to the first inner link central axis;
a first inner link intermediate portion connecting the first inner link end portion and the second inner link end portion;
A first inner link surface;
a second inner link surface disposed on an opposite side to the first inner link surface in a first inner link axial direction with respect to a central axis of the first inner link,
The second inner link plate is
a third inner link end portion including a third inner link hole having a third inner link central axis;
a fourth inner link end portion including a fourth inner link hole having a fourth inner link central axis extending parallel to the third inner link central axis;
a second inner link intermediate portion connecting the third inner link end portion and the fourth inner link end portion;
a third inner link surface that faces the first inner link surface of the first inner link plate in an axial direction of the first inner link when the bicycle chain is in an assembled state;
a fourth inner link surface disposed on an opposite side to the third inner link surface in a second inner link axial direction with respect to the third inner link central axis,
The first outer link plate is
a first inner link plate adjacent to the first inner link plate in an assembled state of the bicycle chain without sandwiching another inner link plate or another outer link plate therebetween;
a first outer link end portion including a first outer link hole having a first outer link central axis;
a second outer link end portion including a second outer link hole having a second outer link central axis extending parallel to the first outer link central axis;
a first outer link intermediate portion connecting the first outer link end portion and the second outer link end portion;
A first outer link surface;
a second outer link surface disposed on an opposite side to the first outer link surface in a first outer link axial direction relative to a central axis of the first outer link,
The second outer link plate is
When the bicycle chain is assembled, the second inner link plate is adjacent to the second inner link plate without sandwiching another inner link plate or another outer link plate therebetween;
a third outer link end portion including a third outer link hole having a third outer link central axis;
a fourth outer link end portion including a fourth outer link hole having a fourth outer link central axis extending parallel to the third outer link central axis;
a second outer link intermediate portion connecting the third outer link end portion and the fourth outer link end portion;
a third outer link surface that faces the first outer link surface of the first outer link plate in the first outer link axial direction when the bicycle chain is in an assembled state;
a fourth outer link surface disposed on an opposite side to the third outer link surface in a second outer link axial direction relative to a central axis of the third outer link,
the bushing has a bushing hole, a first bushing end portion, and a second bushing end portion located on the opposite side of the first bushing end portion in a bushing axial direction relative to a bushing central axis of the bushing, the bushing is configured to be inserted into the first inner link hole and the third inner link hole by press-fitting when the bicycle chain is in an assembled state, the bushing includes at least one of a first radial protrusion extending radially outward from the first bushing end portion relative to the bushing central axis and a second radial protrusion extending radially outward from the second bushing end portion relative to the bushing central axis,
the pin is configured to be inserted through the first outer link hole and the third outer link hole and pass through the bush hole when the bicycle chain is in an assembled state;
an outer diameter of a portion of the bushing press-fitted into the first inner link hole and an outer diameter of a portion of the bushing press-fitted into the third inner link hole are equal to an outer diameter between the portion of the bushing press-fitted into the first inner link hole and the portion of the bushing press-fitted into the third inner link hole,
At least one of the first radial protrusion and the second radial protrusion has an annular shape.
Bicycle chain. 2. The bicycle chain according to claim 1, wherein said bushing includes said first radial projection and said second radial projection. 3. The bicycle chain according to claim 1 or 2 , wherein both the first radial projection and the second radial projection have an annular shape. 4. The bicycle chain according to claim 1, wherein the first radial projection is formed by crimping. 5. The bicycle chain according to claim 1 , wherein the second radial projection is formed by crimping. 6. The bicycle chain according to claim 1, wherein the pin is inserted into the first outer link hole and the third outer link hole by press fitting. 7. The bicycle chain according to claim 1, wherein the first radial projection is formed at a boundary between the first inner link hole and the second inner link surface. 8. The bicycle chain according to claim 1, wherein the first radial projection is formed at a boundary between the third inner link hole and the fourth inner link surface. the pin has a first pin end;
9. The bicycle chain according to claim 1, wherein the first pin end portion is formed around the first outer link hole by crimping. the pin has a second pin end;
10. The bicycle chain according to claim 1, wherein the second pin end portion is formed around the third outer link hole by crimping.