TWI841578B - Bicycle chain - Google Patents

Abstract

[Topic] A bicycle chain is provided to make the movement of the bicycle chain smoother during gear shifting. [Solution] A bicycle chain comprises: a first inner link plate, a second inner link plate, a first outer link plate, a second outer link plate, a hub, and a pin. The first outer link reference line is defined as a line extending parallel to the center line of the first outer link in the transverse direction and passing through the intersection of the first hub and the outer link, and the second outer link reference line is defined as a line extending parallel to the center line of the first outer link in the transverse direction and passing through the intersection of the first outer link end. At least one first outer connecting rod chamfered portion is provided on the first outer connecting rod piece in the first outer connecting rod long side direction relative to the center line of the first outer connecting rod long side direction and is at least partially arranged between the first outer connecting rod reference line and the second outer connecting rod reference line.

Description

Bicycle chain

The present invention relates to a bicycle chain.

Patent document 1 discloses a technology related to a bicycle chain. A pair of inner connecting rods of the chain are connected by a bushing. A pin is inserted through the bushing, and the pin is used to connect a pair of outer connecting rods. [Prior technical document] [Patent document]

[Patent Document 1] U.S. Patent No. 4642078 Specification

[Problems to be solved by the invention]

In the conventional bicycle chain, there is still room for improvement in the movement of the bicycle chain during the gear shifting. The present invention provides a bicycle chain that allows the movement of the bicycle chain during the gear shifting to be smoother. [Means for solving the problem]

The first type of bicycle chain of the present invention comprises: a first inner connecting rod piece, a second inner connecting rod piece, a first outer connecting rod piece, a second outer connecting rod piece, a shaft bushing, and a pin portion; the first inner connecting rod piece comprises: a first inner connecting rod end portion including a first inner connecting rod hole having a first inner connecting rod center axis, a second inner connecting rod end portion including a second inner connecting rod hole having a second inner connecting rod center axis extending parallel to the first inner connecting rod center axis, a first inner connecting rod middle portion connecting the first inner connecting rod end portion and the second inner connecting rod end portion, a first inner connecting rod surface, and a first inner connecting rod surface relative to the first inner connecting rod. The second inner connecting rod surface is arranged on the opposite side of the first inner connecting rod surface in the first inner connecting rod axis direction of the inner connecting rod center axis; the second inner connecting rod plate includes: a third inner connecting rod end portion including a third inner connecting rod hole having a third inner connecting rod center axis, a fourth inner connecting rod end portion including a fourth inner connecting rod hole having a fourth inner connecting rod center axis extending parallel to the third inner connecting rod center axis, a second inner connecting rod middle portion connecting the third inner connecting rod end portion and the fourth inner connecting rod end portion, and a second inner connecting rod middle portion extending in the first inner connecting rod axis direction toward the first inner connecting rod in the assembled state of the bicycle chain. The third inner connecting rod surface of the rod piece is arranged on the opposite side of the third inner connecting rod surface in the second inner connecting rod axis direction relative to the third inner connecting rod center axis; the first outer connecting rod piece is arranged to be adjacent to the first inner connecting rod piece without other inner connecting rod pieces or other outer connecting rod pieces in the assembled state of the bicycle chain, and includes: a first outer connecting rod end portion including a first outer connecting rod hole having a first outer connecting rod center axis, a second outer connecting rod center axis extending parallel to the first outer connecting rod center axis, The second outer connecting rod end having a second outer connecting rod hole, a first outer connecting rod middle portion connecting the first outer connecting rod end and the second outer connecting rod end, a first outer connecting rod surface, and a second outer connecting rod surface arranged on the opposite side of the first outer connecting rod surface in the first outer connecting rod axis direction relative to the center axis of the first outer connecting rod; the second outer connecting rod plate, in the assembled state of the bicycle chain, is arranged to be adjacent to the second inner connecting rod plate without other inner connecting rod plates or other outer connecting rod plates in between, and includes: a third outer connecting rod having a third outer connecting rod hole having a third outer connecting rod center axis The invention relates to a fourth outer connecting rod end portion, a fourth outer connecting rod end portion including a fourth outer connecting rod hole having a fourth outer connecting rod center axis extending parallel to the third outer connecting rod center axis, a second outer connecting rod middle portion connecting the third outer connecting rod end portion and the fourth outer connecting rod end portion, a third outer connecting rod surface facing the first outer connecting rod surface in the direction of the first outer connecting rod axis toward the first outer connecting rod plate in the assembled state of the bicycle chain, and a fourth outer connecting rod surface arranged on the opposite side of the third outer connecting rod surface in the direction of the second outer connecting rod axis relative to the third outer connecting rod center axis; the shaft bushing has a shaft The bushing hole is inserted into the first inner connecting rod hole and the third inner connecting rod hole in the assembled state of the bicycle chain. The bushing has a first bushing outer connecting rod intersection and a second bushing outer connecting rod intersection. The outer peripheral surface of the bushing and the center line of the first outer connecting rod in the longitudinal direction of the first outer connecting rod of the first outer connecting rod plate intersect each other at the first bushing outer connecting rod intersection and the second bushing outer connecting rod intersection when viewed from the axis direction of the first outer connecting rod. The first bushing outer connecting rod intersection is arranged closer to the center of the first outer connecting rod in the transverse direction of the first outer connecting rod of the first outer connecting rod plate than the second bushing outer connecting rod intersection. The first outer connecting rod transverse direction center line is a line perpendicularly intersecting the first outer connecting rod longitudinal direction center line. The pin portion, in the assembled state of the bicycle chain, is inserted into the first outer connecting rod hole and the third outer connecting rod hole and passes through the axle bushing hole. The first outer connecting rod reference line is defined as a line extending parallel to the first outer connecting rod transverse direction center line and passing through the intersection of the first axle bushing outer connecting rod. The second outer connecting rod reference line is defined as a line extending parallel to the first outer connecting rod transverse direction center line and passing through the intersection of the first outer connecting rod end edge. The outer connecting rod end edge intersection point is a point where the center line of the first outer connecting rod long side direction of the first outer connecting rod piece and the first outer connecting rod end edge of the first outer connecting rod end portion of the first outer connecting rod piece intersect each other when viewed from the axial direction of the first outer connecting rod. At least one first outer connecting rod chamfered portion is provided on the first outer connecting rod piece, and at least a part of the at least one first outer connecting rod chamfered portion is arranged between the first outer connecting rod reference line and the second outer connecting rod reference line in the first outer connecting rod long side direction of the first outer connecting rod piece relative to the center line of the first outer connecting rod long side direction. According to the bicycle chain of the first type, the pin portion is inserted into the axle bushing, so the bicycle chain has high rigidity and reduces wear of the bicycle chain. At least one first outer link chamfered portion makes the movement of the bicycle chain smoother during gear shifting and reduces driving noise when the bicycle chain is driven.

According to the second type of bicycle chain of the first type, the at least one first outer link chamfer is provided on the surface of the second outer link. With the second type of bicycle chain, the first outer link chamfer makes the movement of the bicycle chain smoother during gear shifting, and reduces the driving sound of the bicycle chain when driving.

According to the third type of bicycle chain of the first or second type, the at least one first outer link chamfer is provided at the end of the second outer link. With the third type of bicycle chain, the first outer link chamfer makes the movement of the bicycle chain smoother during gear shifting.

According to the bicycle chain of the fourth embodiment of the third embodiment, the at least one first outer connecting rod chamfer is provided on the surface of the second outer connecting rod. With the bicycle chain of the fourth embodiment, the first outer connecting rod chamfer makes the movement of the bicycle chain smoother during the gear shifting, and reduces the driving sound when the bicycle chain is driven.

According to the bicycle chain of the fifth embodiment of any one of the first to fourth embodiments, the at least one first outer link chamfer is disposed at the middle portion of the first outer link. With the bicycle chain of the fifth embodiment, the first outer link chamfer allows the bicycle chain to move more smoothly during gear shifting.

According to the bicycle chain of the sixth aspect of the fifth aspect, the at least one first outer link chamfer is provided on the first outer link surface. With the bicycle chain of the sixth aspect, the sprocket teeth can easily enter between the outer link plates, so that the bicycle chain can move more smoothly during gear shifting.

According to the bicycle chain of the seventh aspect of the fifth aspect, the at least one first outer link chamfer is provided on the surface of the second outer link. With the bicycle chain of the seventh aspect, the movement of the bicycle chain during gear shifting is smoother.

According to the bicycle chain of the eighth aspect of any one of the first to seventh aspects, at least one first inner link chamfer is provided on the first inner link plate. With the bicycle chain of the eighth aspect, the movement of the bicycle chain during gear shifting is made smoother.

According to the bicycle chain of the 9th embodiment of the 8th embodiment, the axle bushing has a first axle bushing inner connecting rod intersection and a second axle bushing inner connecting rod intersection, and the outer peripheral surface of the axle bushing and the center line of the first inner connecting rod in the longitudinal direction of the first inner connecting rod of the first inner connecting rod plate intersect each other when viewed from the axis direction of the first inner connecting rod, and the first axle bushing inner connecting rod intersection and the second axle bushing inner connecting rod intersection intersect each other, and the first The shaft bushing inner connecting rod intersection point is arranged on the first inner connecting rod transverse direction center line closer to the first inner connecting rod plate than the second shaft bushing inner connecting rod intersection point. The first inner connecting rod transverse direction center line is a line perpendicularly intersecting the first inner connecting rod longitudinal direction center line. The first inner connecting rod reference line is defined as a line extending parallel to the first inner connecting rod transverse direction center line and passing through the first inner connecting rod. The second inner connecting rod reference line is defined as a line extending parallel to the center line of the first inner connecting rod in the transverse direction and passing through the intersection of the first inner connecting rod end edge, and the intersection of the first inner connecting rod end edge is observed from the axial direction of the first inner connecting rod, so that the center line of the first inner connecting rod in the longitudinal direction of the first inner connecting rod of the first inner connecting rod piece and the end of the first inner connecting rod of the first inner connecting rod piece are parallel to each other. At the point where the ends of the first inner connecting rods of the first inner connecting rods intersect each other, the at least one first inner connecting rod chamfered portion is provided on the first inner connecting rod piece, and at least a part of the at least one first inner connecting rod chamfered portion is arranged between the first inner connecting rod reference line and the second inner connecting rod reference line in the first inner connecting rod long side direction of the first inner connecting rod piece relative to the center line of the first inner connecting rod long side direction. By means of the bicycle chain of the ninth type, the contact of the bicycle chain when bending can be suppressed for at least one of the contact between the inner connecting rod piece and the roller and the contact between the inner connecting rod piece and the outer connecting rod piece, so that the movement of the bicycle chain when shifting is smoother.

According to the bicycle chain of the tenth aspect of any one of the first to ninth aspects, at least one second outer link chamfer is provided on the second outer link plate. With the bicycle chain of the tenth aspect, the movement of the bicycle chain during the gear shifting is smoother, and the driving sound of the bicycle chain during the driving is reduced.

According to the 11th bicycle chain of any one of the 1st to 10th embodiments, at least one second inner link chamfer is provided on the second inner link plate. With the 11th bicycle chain, the movement of the bicycle chain during gear shifting is smoother.

The twelfth aspect of the bicycle chain of the present invention comprises: a first inner connecting rod piece, a second inner connecting rod piece, a first outer connecting rod piece, a second outer connecting rod piece, a shaft bushing, and a pin portion; the first inner connecting rod piece comprises: a first inner connecting rod end portion comprising a first inner connecting rod hole having a first inner connecting rod center axis, a second inner connecting rod end portion comprising a second inner connecting rod hole having a second inner connecting rod center axis extending parallel to the first inner connecting rod center axis, a first inner connecting rod middle portion connecting the first inner connecting rod end portion and the second inner connecting rod end portion, a first inner connecting rod surface, and a first inner connecting rod surface having a first inner connecting rod hole and a second inner connecting rod hole extending parallel to the first inner connecting rod center axis. The first inner connecting rod has a first inner connecting rod axis and a second inner connecting rod surface disposed on the opposite side of the first inner connecting rod surface in the first inner connecting rod axis direction; the second inner connecting rod piece includes: a third inner connecting rod end portion including a third inner connecting rod hole having a third inner connecting rod center axis, a fourth inner connecting rod end portion including a fourth inner connecting rod hole having a fourth inner connecting rod center axis extending parallel to the third inner connecting rod center axis, a second inner connecting rod middle portion connecting the third inner connecting rod end portion and the fourth inner connecting rod end portion, and a second inner connecting rod middle portion extending in the first inner connecting rod axis direction toward the first inner connecting rod in the assembled state of the bicycle chain. The first outer connecting rod portion includes a first outer connecting rod hole having a central axis of the first outer connecting rod, a second outer connecting rod middle portion having a first outer connecting rod hole extending parallel to the central axis of the first outer connecting rod, and a third inner connecting rod surface of the first inner connecting rod portion, and a fourth inner connecting rod surface arranged on the opposite side of the third inner connecting rod surface in a second inner connecting rod axis direction relative to the central axis of the third inner connecting rod; the first outer connecting rod portion is arranged to be adjacent to the first inner connecting rod portion without other inner connecting rod portions or other outer connecting rod portions in an assembled state of the bicycle chain, and includes: a first outer connecting rod end portion including a first outer connecting rod hole having a central axis of the first outer connecting rod, a second outer connecting rod middle portion having a first outer connecting rod hole extending parallel to the central axis of the first outer connecting rod, The invention relates to a first outer connecting rod end portion having a second outer connecting rod hole at the center of the central axis, a first outer connecting rod middle portion connecting the first outer connecting rod end portion and the second outer connecting rod end portion, a first outer connecting rod surface, and a second outer connecting rod surface arranged on the opposite side of the first outer connecting rod surface in the first outer connecting rod axial direction relative to the center axis of the first outer connecting rod; the second outer connecting rod plate, in the above-mentioned assembled state, is arranged to be adjacent to the second inner connecting rod plate without other inner connecting rod plates or other outer connecting rod plates in between, and includes: a third outer connecting rod end portion including a third outer connecting rod hole having a third outer connecting rod center axis , a fourth outer connecting rod end portion including a fourth outer connecting rod hole having a fourth outer connecting rod center axis extending parallel to the third outer connecting rod center axis, a second outer connecting rod middle portion connecting the third outer connecting rod end portion and the fourth outer connecting rod end portion, a third outer connecting rod surface facing the first outer connecting rod surface in the direction of the first outer connecting rod axis toward the first outer connecting rod plate in the assembled state of the bicycle chain, and a fourth outer connecting rod surface disposed on the opposite side of the third outer connecting rod surface in the direction of the second outer connecting rod axis relative to the third outer connecting rod center axis; the shaft bushing having a shaft bushing The hole is inserted into the first inner connecting rod hole and the third inner connecting rod hole in the assembled state of the bicycle chain, the axle bushing has a first axle bushing inner connecting rod intersection and a second axle bushing inner connecting rod intersection, the outer peripheral surface of the axle bushing and the center line of the first inner connecting rod in the longitudinal direction of the first inner connecting rod of the first inner connecting rod sheet intersect each other when viewed from the axial direction of the first inner connecting rod, and the first axle bushing inner connecting rod intersection is arranged closer to the center of the first inner connecting rod in the transverse direction of the first inner connecting rod of the first inner connecting rod sheet than the second axle bushing inner connecting rod intersection The first inner connecting rod transverse direction center line is a line perpendicularly intersecting the first inner connecting rod longitudinal direction center line. The pin portion, in the assembled state of the bicycle chain, is inserted into the first outer connecting rod hole and the third outer connecting rod hole and passes through the axle bushing hole. The first inner connecting rod reference line is defined as a line extending parallel to the first inner connecting rod transverse direction center line and passing through the intersection of the first axle bushing inner connecting rod. The second inner connecting rod reference line is defined as a line extending parallel to the first inner connecting rod transverse direction center line and passing through the intersection of the first inner connecting rod end edge. The first inner connecting rod end edge intersection point is a point where the first inner connecting rod long side center line of the first inner connecting rod piece and the first inner connecting rod end edge of the first inner connecting rod piece intersect each other when viewed from the axial direction of the first inner connecting rod. At least one first inner connecting rod chamfered portion is provided on the first inner connecting rod piece, and at least a part of the at least one first inner connecting rod chamfered portion is arranged between the first inner connecting rod reference line and the second inner connecting rod reference line in the first inner connecting rod long side direction of the first inner connecting rod piece relative to the first inner connecting rod long side center line. According to the bicycle chain of the twelfth embodiment, the pin portion is inserted into the axle bushing, so the bicycle chain has high rigidity and suppresses wear of the bicycle chain. Moreover, the chamfered portion of the first inner link makes the movement of the bicycle chain smoother during gear shifting. Furthermore, the driving noise when the bicycle chain is driven is reduced.

According to the bicycle chain of the 13th aspect of the 12th aspect, the at least one first inner link chamfer is provided on the surface of the first inner link. With the bicycle chain of the 13th aspect, the movement of the bicycle chain during gear shifting is smoother.

According to the bicycle chain of the 14th aspect of the 12th or 13th aspect, the at least one first inner link chamfer is provided at the end of the second inner link. With the bicycle chain of the 14th aspect, the movement of the bicycle chain during gear shifting is smoother.

According to the bicycle chain of the 15th aspect of the 14th aspect, the at least one first inner link chamfer is provided on the surface of the first inner link. With the bicycle chain of the 15th aspect, the movement of the bicycle chain during the gear shifting is smoother.

According to the bicycle chain of the 16th embodiment of any one of the 12th to 15th embodiments, the at least one first inner link chamfer is disposed at the middle portion of the first inner link. With the bicycle chain of the 16th embodiment, the movement of the bicycle chain during gear shifting is smoother.

According to the bicycle chain of the 17th aspect of the 16th aspect, the at least one first inner link chamfer is provided on the surface of the first inner link. With the bicycle chain of the 17th aspect, the sprocket teeth can easily enter between the inner link plates, so that the bicycle chain can move more smoothly during gear shifting.

According to the bicycle chain of the 18th aspect of the 16th aspect, the at least one first inner link chamfer is provided on the surface of the second inner link. With the bicycle chain of the 18th aspect, the movement of the bicycle chain during gear shifting is smoother.

According to the bicycle chain of the 19th aspect of any one of the 12th to 18th aspects, at least one first outer connecting rod chamfer is provided on the first outer connecting rod plate. With the bicycle chain of the 19th aspect, the movement of the bicycle chain during the gear shifting is made smoother, and the driving sound of the bicycle chain during the driving is reduced.

According to the 20th bicycle chain of any one of the 12th to 19th aspects, at least one second outer connecting rod chamfer is provided on the second outer connecting rod plate. With the 20th bicycle chain, the movement of the bicycle chain during gear shifting is smoother, and the driving sound of the bicycle chain during driving is reduced.

According to the 21st bicycle chain of any one of the 12th to 20th embodiments, at least one second inner link chamfer is provided on the second inner link plate. With the 21st bicycle chain, the movement of the bicycle chain during gear shifting is smoother.

The 22nd aspect of the bicycle chain of the present invention comprises: a first inner connecting rod plate, a second inner connecting rod plate, a first outer connecting rod plate, a second outer connecting rod plate, a bushing, a pin portion, a metal retaining member, and a resin member; the first inner connecting rod plate comprises: a first inner connecting rod end portion including a first inner connecting rod hole having a first inner connecting rod center axis, a second inner connecting rod end portion including a second inner connecting rod center axis extending parallel to the first inner connecting rod center axis, The second inner connecting rod piece comprises: a second inner connecting rod end portion having a third inner connecting rod hole, a first inner connecting rod middle portion connecting the first inner connecting rod end portion and the second inner connecting rod end portion, a first inner connecting rod surface, and a second inner connecting rod surface arranged on the opposite side of the first inner connecting rod surface in the first inner connecting rod axial direction relative to the center axis of the first inner connecting rod; the second inner connecting rod piece comprises: a third inner connecting rod end portion having a third inner connecting rod hole having a third inner connecting rod center axis , a fourth inner connecting rod end portion including a fourth inner connecting rod hole having a fourth inner connecting rod center axis extending parallel to the third inner connecting rod center axis, a second inner connecting rod middle portion connecting the third inner connecting rod end portion and the fourth inner connecting rod end portion, a third inner connecting rod surface facing the first inner connecting rod surface in the direction of the first inner connecting rod axis toward the first inner connecting rod plate in the assembled state of the bicycle chain, The second inner connecting rod having a central axis is arranged on a fourth inner connecting rod surface on the opposite side of the third inner connecting rod surface in the axial direction; the first outer connecting rod plate is arranged to be adjacent to the first inner connecting rod plate without other inner connecting rod plates or other outer connecting rod plates in the assembled state of the bicycle chain, and comprises: a first outer connecting rod end portion including a first outer connecting rod hole having a central axis of the first outer connecting rod, ... The second outer connecting rod end portion of the second outer connecting rod hole extending parallel to the axis, the first outer connecting rod middle portion connecting the first outer connecting rod end portion and the second outer connecting rod end portion, the first outer connecting rod surface, and the second outer connecting rod surface arranged on the opposite side of the first outer connecting rod surface in the first outer connecting rod axial direction relative to the center axis of the first outer connecting rod; the second outer connecting rod plate is arranged adjacent to the first outer connecting rod plate in the above-mentioned assembled state. The invention relates to a second inner connecting rod piece without any other inner connecting rod piece or other outer connecting rod piece in between, and comprising: a third outer connecting rod end portion including a third outer connecting rod hole having a third outer connecting rod center axis, a fourth outer connecting rod end portion including a fourth outer connecting rod hole having a fourth outer connecting rod center axis extending parallel to the third outer connecting rod center axis, a second outer connecting rod middle portion connecting the third outer connecting rod end portion and the fourth outer connecting rod end portion, In the assembled state of the bicycle chain, the third outer connecting rod surface of the first outer connecting rod surface is arranged in the direction of the first outer connecting rod axis toward the first outer connecting rod plate, and the fourth outer connecting rod surface is arranged on the opposite side of the third outer connecting rod surface in the direction of the second outer connecting rod axis relative to the center axis of the third outer connecting rod; the shaft bushing has an inner peripheral surface constituting the shaft bushing hole, and the shaft bushing is inserted into the shaft bushing in the assembled state of the bicycle chain. The first inner connecting rod hole and the third inner connecting rod hole, the pin portion has an outer peripheral surface, and is inserted into the first inner connecting rod hole and the third inner connecting rod hole and passes through the shaft bushing hole when the bicycle chain is assembled; the metal retaining member is arranged on one of the inner peripheral surface of the shaft bushing and the outer peripheral surface of the pin portion, and the metal retaining member includes a plurality of retaining holes, and the resin member is arranged in the plurality of retaining holes. By using the bicycle chain of the 22nd type, the friction between the shaft bushing and the pin portion can be reduced, so that the driving efficiency of the bicycle chain can be improved when it is driven.

According to the bicycle chain of the 22nd aspect or the 23rd aspect, the metal retaining member is disposed on the inner peripheral surface of the axle bushing. With the bicycle chain of the 23rd aspect, the friction between the axle bushing and the pin portion can be reduced.

According to the bicycle chain of the 24th aspect of the 22nd or 23rd aspect, the bushing is formed of the first material, and the metal retaining member is formed of the first material. According to the bicycle chain of the 24th aspect, since the bushing and the metal retaining member are made of the same material, the bushing and the metal retaining member can be firmly coupled.

According to the bicycle chain of the 25th aspect of the 22nd or 23rd aspect, the bushing is formed of a first material, and the metal retaining member is formed of a second material different from the first material. With the bicycle chain of the 25th aspect, the degree of freedom in combining the materials of the bushing and the metal retaining member can be increased.

The 26th type of bicycle chain of the present invention comprises: a first inner connecting rod piece, a second inner connecting rod piece, a first outer connecting rod piece, a second outer connecting rod piece, a shaft bushing, and a pin portion; the first inner connecting rod piece comprises: a first inner connecting rod end portion comprising a first inner connecting rod hole having a first inner connecting rod center axis, a second inner connecting rod end portion comprising a second inner connecting rod hole having a second inner connecting rod center axis extending parallel to the first inner connecting rod center axis, and a first inner connecting rod end portion comprising a second inner connecting rod hole having a second inner connecting rod center axis extending parallel to the first inner connecting rod center axis. The inner connecting rod end portion is connected to the first inner connecting rod middle portion of the second inner connecting rod end portion, the first inner connecting rod surface, and the second inner connecting rod surface is arranged on the opposite side of the first inner connecting rod surface in the first inner connecting rod axial direction relative to the center axis of the first inner connecting rod; the second inner connecting rod piece includes: a third inner connecting rod end portion including a third inner connecting rod hole having a third inner connecting rod center axis, a fourth inner connecting rod having a third inner connecting rod hole extending parallel to the center axis of the third inner connecting rod, The fourth inner connecting rod end portion of the fourth inner connecting rod hole at the center axis of the rod, the second inner connecting rod middle portion connecting the third inner connecting rod end portion and the fourth inner connecting rod end portion, the third inner connecting rod surface facing the first inner connecting rod surface in the direction of the first inner connecting rod axis toward the first inner connecting rod plate in the assembled state of the bicycle chain, and the fourth inner connecting rod surface disposed on the opposite side of the third inner connecting rod surface in the direction of the second inner connecting rod axis relative to the center axis of the third inner connecting rod. The first outer connecting rod plate is arranged to be adjacent to the first inner connecting rod plate without other inner connecting rod plates or other outer connecting rod plates in the assembled state of the bicycle chain, and comprises: a first outer connecting rod end portion including a first outer connecting rod hole having a central axis of the first outer connecting rod, a second outer connecting rod end portion including a second outer connecting rod hole having a central axis of the second outer connecting rod extending parallel to the central axis of the first outer connecting rod, and a second outer connecting rod end portion including a second outer connecting rod hole having a central axis of the second outer connecting rod extending parallel to the central axis of the first outer connecting rod. The first outer connecting rod middle portion whose end is connected to the end of the second outer connecting rod, the first outer connecting rod surface, and the second outer connecting rod surface arranged on the opposite side of the first outer connecting rod surface in the first outer connecting rod axial direction relative to the center axis of the first outer connecting rod; the second outer connecting rod piece, in the above-mentioned assembled state, is arranged to be adjacent to the second inner connecting rod piece without other inner connecting rod pieces or other outer connecting rod pieces in between, and includes: a third outer connecting rod having a center axis The third outer connecting rod end portion of the third outer connecting rod hole, the fourth outer connecting rod end portion including the fourth outer connecting rod hole having the fourth outer connecting rod center axis extending parallel to the third outer connecting rod center axis, the second outer connecting rod middle portion connecting the third outer connecting rod end portion and the fourth outer connecting rod end portion, the third outer connecting rod surface facing the first outer connecting rod surface in the direction of the first outer connecting rod axis toward the first outer connecting rod plate in the assembled state of the bicycle chain, The fourth outer connecting rod surface is arranged on the opposite side of the third outer connecting rod surface in the axial direction of the second outer connecting rod at the center axis of the third outer connecting rod; the bushing has: a bushing hole, a first bushing end, and a second bushing end arranged on the opposite side of the first bushing end in the axial direction of the bushing relative to the center axis of the bushing; the bushing is inserted into the first inner connecting rod hole and the first inner connecting rod hole by press-fitting in the assembled state of the bicycle chain. The axle bushing includes at least one of a first radial protrusion extending radially outward from the first axle bushing end relative to the axle bushing center axis and a second radial protrusion extending radially outward from the second axle bushing end relative to the axle bushing center axis; the pin portion is inserted through the first outer connecting rod hole and the third outer connecting rod hole and passes through the axle bushing hole when the bicycle chain is assembled. The axle bushing can be firmly fixed to the inner connecting rod plate by the bicycle chain of the twenty-sixth embodiment.

According to the bicycle chain of the 27th aspect of the 26th aspect, the axle bushing includes: the first radial protrusion and the second radial protrusion. With the bicycle chain of the 27th aspect, the axle bushing can be firmly fixed to the inner link plate.

According to the bicycle chain of the 28th aspect of the 26th or 27th aspect, the first radial protrusion has a ring shape. With the bicycle chain of the 28th aspect, the axle bushing can be more firmly fixed to the inner link plate.

According to the bicycle chain of the 29th aspect of any one of the 26th to 28th aspects, the second radial protrusion has a ring shape. With the bicycle chain of the 29th aspect, the axle bushing can be more firmly fixed to the inner link plate.

According to the bicycle chain of the 30th aspect of any one of the 26th to 29th aspects, the first radial protrusion is formed by a countersunk stitching method. With the bicycle chain of the 30th aspect, the axle bushing can be efficiently fixed to the inner link plate.

According to the bicycle chain of the 31st aspect of any one of the 26th to 30th aspects, the second radial protrusion is formed by a countersunk stitching method. With the bicycle chain of the 31st aspect, the axle bushing can be efficiently fixed to the inner link plate.

According to the bicycle chain of the 32nd type of any one of the above-mentioned types 26 to 31, the above-mentioned pin portion is inserted into the above-mentioned first outer connecting rod hole and the above-mentioned third outer connecting rod hole by press-fitting. By means of the bicycle chain of the 32nd type, the pin portion can be efficiently fixed to the outer connecting rod plate. [Effect of the invention]

The bicycle chain of the present invention can make the movement of the bicycle chain smoother during speed change.

<First embodiment> Refer to FIG. 1 for explanation of a human-powered vehicle using a bicycle chain. FIG. 1 is a view showing a human-powered vehicle, i.e., a bicycle A, viewed from above as an example of a human-powered vehicle. The human-powered vehicle here refers to a vehicle that uses human power at least partially as the power for driving, including a vehicle that assists human power with electricity. Vehicles that use power other than human power are not included in human-powered vehicles. Vehicles that are powered only by internal combustion engines are not included in human-powered vehicles. Conventional human-powered vehicles are intended to be small and light vehicles that do not require a driver's license on public roads. The human-powered vehicle shown in the figure includes a bicycle A. Specifically, the human-powered vehicle is bicycle A. Bicycle A includes a transmission system B.

The transmission system B is a chain transmission type. The transmission system B includes: a bicycle crank assembly C, a bicycle sprocket (hereinafter referred to as "sprocket D"), and a bicycle chain 10. The sprocket D has: sprocket teeth for engaging the bicycle chain 10. The sprocket D includes: a front sprocket E and a rear sprocket F. The bicycle crank assembly C includes: a crank axle Ca rotatably supported on the frame of the bicycle A, and a pair of crank arms Cb respectively provided at both ends of the crank axle Ca. The pedal is rotatably mounted on the front end of each crank arm Cb.

The front sprocket E is provided on the crankshaft Ca and can rotate integrally with the crankshaft Ca. The rear sprocket F is provided on 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 the user riding on the 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 FIGS. 2 to 9. In FIG. 3, the first inner link 12 and the second inner link 14 connected on the right side, and the additional roller 28 are shown by imaginary lines. In FIG. 3, the first outer link 16 and the second outer link 18 connected on the left side, and the additional pin 23 are shown by imaginary lines. FIG. 6 is a cross-sectional view of the portion of the bicycle chain 10 including the first inner link 12 and the first outer link 16 cut along the VI-VI line of FIG. 3, and in this figure, the roller 24 and the additional roller 28 are omitted. Fig. 7 is a cross-sectional view of a portion of the bicycle chain 10 including the second inner link 14 and the second outer link 18, cut along the VII-VII line of Fig. 3, in which the roller 24 and the additional roller 28 are omitted. Fig. 8 is the same figure as Fig. 4. Fig. 9 is the same figure as Fig. 6.

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

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

As shown in FIG. 4 , the first inner connecting rod piece 12 has: a first inner connecting rod longitudinal centerline LCA, and a first inner connecting rod transverse centerline LCB perpendicular to the first inner connecting rod longitudinal centerline LCA. The first inner connecting rod distance LGA is defined as between the first inner connecting rod central axis AX1 and the second inner connecting rod central axis AX2 in the first inner connecting rod longitudinal direction DE relative to the first inner connecting rod longitudinal centerline LCA.

In this embodiment, the first inner connecting rod longitudinal centerline LCA and the first inner connecting rod transverse centerline LCB are defined according to the first inner connecting rod piece 12. As shown in FIG. 4, the first inner connecting rod longitudinal centerline LCA is defined as: a line extending along the longitudinal direction of the first inner connecting rod piece 12 when the first inner connecting rod piece 12 is observed from the direction along the axial direction DA of the first inner connecting rod, and a line passing through the first inner connecting rod center axis AX1 and the second inner connecting rod center axis AX2. The first inner connecting rod transverse centerline LCB is defined as a line perpendicularly intersecting the first inner connecting rod longitudinal centerline LCA and passing through the midpoint between the first inner connecting rod center axis AX1 and the second inner connecting rod center axis AX2.

As shown in FIG. 3 , the second inner connecting rod piece 14 includes: a third inner connecting rod end portion 42 including a third inner connecting rod hole 40 having a third inner connecting rod center axis AX3, a fourth inner connecting rod end portion 46 including a fourth inner connecting rod hole 44 having a fourth inner connecting rod center axis AX4 extending parallel to the third inner connecting rod center axis AX3, and a second inner connecting rod middle portion 48 connecting the third inner connecting rod end portion 42 and the fourth inner connecting rod end portion 46. The second inner link plate 14 includes: a third inner link surface 14A facing the first inner link surface 12A of the first inner link plate 12 in the first inner link axial direction DA when the bicycle chain 10 is assembled, 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 relative to the third inner link center axis AX3.

As shown in FIG. 5 , the second inner connecting rod piece 14 has: a second inner connecting rod longitudinal center line LCC, and a second inner connecting rod transverse center line LCD perpendicular to the second inner connecting rod longitudinal center line LCC. The second inner connecting rod distance LGB is defined as between the third inner connecting rod center axis AX3 and the fourth inner connecting rod center axis AX4 in the second inner connecting rod longitudinal direction DF relative to the second inner connecting rod longitudinal center line LCC. The first inner connecting rod distance LGA and the second inner connecting rod distance LGB are preferably in the range of 9 mm to 13 mm, respectively. For example, the first inner connecting rod distance LGA and the second inner connecting rod distance LGB are set to 12.7 mm or 10 mm, respectively.

In this embodiment, the second inner connecting rod longitudinal center line LCC and the second inner connecting rod transverse center line LCD are defined according to the second inner connecting rod piece 14. As shown in FIG. 5, the second inner connecting rod longitudinal center line LCC is defined as: a line extending along the longitudinal direction of the second inner connecting rod piece 14 when the second inner connecting rod piece 14 is observed from the direction along the second inner connecting rod axial direction DB, and a line passing through the third inner connecting rod center axis AX3 and the fourth inner connecting rod center axis AX4. The second inner connecting rod transverse center line LCD is defined as a line perpendicularly intersecting the second inner connecting rod longitudinal center line LCC and passing through the midpoint between the third inner connecting rod center axis AX3 and the fourth inner connecting rod center axis AX4.

As shown in FIG. 3 , the first outer connecting rod 16 is adjacent to the first inner connecting rod 12 in the assembled state of the bicycle chain 10, and no other inner connecting rod or other outer connecting rod is interposed therebetween. The first outer connecting rod 16 includes a first outer connecting rod end 52 including a first outer connecting rod hole 50 having a first outer connecting rod center axis BX1, a second outer connecting rod end 56 including a second outer connecting rod hole 54 having a second outer connecting rod center axis BX2 extending parallel to the first outer connecting rod center axis BX1, and a first outer connecting rod middle portion 58 connecting the first outer connecting rod end 52 and the second outer connecting rod end 56. The first outer link piece 16 includes a first outer link surface 16A and a second outer link surface 16B disposed on the opposite side of the first outer link surface 16A in the first outer link axis direction DC with respect to the first outer link center axis BX1.

As shown in FIG. 4 , the first outer connecting rod piece 16 has: a first outer connecting rod longitudinal center line LCE, and a first outer connecting rod transverse center line LCF perpendicular to the first outer connecting rod longitudinal center line LCE. The first outer connecting rod distance LGC is defined as between the first outer connecting rod central axis BX1 and the second outer connecting rod central axis BX2 in the first outer connecting rod longitudinal direction DG relative to the first outer connecting rod longitudinal center line LCE.

In this embodiment, the first outer connecting rod longitudinal center line LCE and the first outer connecting rod transverse center line LCF are defined according to the first outer connecting rod piece 16. As shown in FIG. 4, the first outer connecting rod longitudinal center line LCE is defined as: a line extending along the longitudinal direction of the first outer connecting rod piece 16 when the first outer connecting rod piece 16 is observed from the direction along the axial direction DC of the first outer connecting rod, and a line passing through the first outer connecting rod central axis BX1 and the second outer connecting rod central axis BX2. The first outer connecting rod transverse center line LCF is defined as a line perpendicularly intersecting the first outer connecting rod longitudinal center line LCE and passing through the midpoint between the first outer connecting rod central axis BX1 and the second outer connecting rod central axis BX2.

As shown in FIG. 3 , the second outer connecting rod 18 is adjacent to the second inner connecting rod 14 in the assembled state of the bicycle chain 10, and there is no other inner connecting rod or other outer connecting rod in between. The second outer connecting rod 18 includes: a third outer connecting rod end 62 including a third outer connecting rod hole 60 having a third outer connecting rod center axis BX3, a fourth outer connecting rod end 66 including a fourth outer connecting rod hole 64 having a fourth outer connecting rod center axis BX4 extending parallel to the third outer connecting rod center axis BX3, and a second outer connecting rod middle portion 68 connecting the third outer connecting rod end 62 and the fourth outer connecting rod end 66. The second outer link plate 18 includes: a third outer link surface 18A facing the first outer link surface 16A of the first outer link plate 16 in the first outer link axis direction DC when the bicycle chain 10 is assembled, and a fourth outer link surface 18B arranged on the opposite side of the third outer link surface 18A in the second outer link axis direction DD relative to the third outer link center axis BX3.

As shown in FIG. 5 , the second outer connecting rod piece 18 has: a second outer connecting rod longitudinal center line LCG, and a second outer connecting rod transverse center line LCH perpendicular to the second outer connecting rod longitudinal center line LCG. The second outer connecting rod distance LGD is defined as between the third outer connecting rod center axis BX3 and the fourth outer connecting rod center axis BX4 in the second outer connecting rod longitudinal direction DH relative to the second outer connecting rod longitudinal center line LCG. The first outer connecting rod distance LGC and the second outer connecting rod distance LGD are preferably in the range of 9 mm to 13 mm, respectively. For example, the first outer connecting rod distance LGC and the second outer connecting rod distance LGD are set to 12.7 mm or 10 mm, respectively.

In this embodiment, the second outer connecting rod longitudinal center line LCG and the second outer connecting rod transverse center line LCH are defined according to the second outer connecting rod piece 18. As shown in FIG. 5, the second outer connecting rod longitudinal center line LCG is defined as: a line extending along the longitudinal direction of the second outer connecting rod piece 18 when the second outer connecting rod piece 18 is observed from the direction along the axial direction DD of the second outer connecting rod, and a line passing through the third outer connecting rod center axis BX3 and the fourth outer connecting rod center axis BX4. The second outer connecting rod transverse center line LCH is defined as a line perpendicularly intersecting the second outer connecting rod longitudinal center line LCG and passing through the midpoint between the third outer connecting rod center axis BX3 and the fourth outer connecting rod center axis BX4.

As shown in FIG. 3 , the axle bushing 20 has an axle bushing hole 20A. The axle bushing 20 is inserted into the first inner connecting rod hole 30 and the third inner connecting rod hole 40 when the bicycle chain 10 is assembled. The additional axle bushing 26, which is different from the axle bushing 20 inserted into the first inner connecting rod hole 30 and the third inner connecting rod hole 40, has an additional axle bushing hole 26A. The additional axle bushing 26 is inserted into the second inner connecting rod hole 34 and the fourth inner connecting rod hole 44 when the bicycle chain 10 is assembled.

As shown in FIG. 8 , the bushing 20 has a first bushing outer connecting rod intersection SA1 and a second bushing outer connecting rod intersection SA2. The outer peripheral surface 20B of the bushing 20 and the first outer connecting rod longitudinal center line LCE of the first outer connecting rod plate 16 intersect each other at the first bushing outer connecting rod intersection SA1 and the second bushing outer connecting rod intersection SA2 when viewed from the first outer connecting rod axial direction DC. The first bushing outer connecting rod intersection SA1 is arranged closer to the first outer connecting rod transverse center line LCF of the first outer connecting rod plate 16 than the second bushing outer connecting rod intersection SA2. The first outer connecting rod transverse direction center line LCF is a line perpendicularly intersecting the first outer connecting rod longitudinal direction center line LCE.

As shown in FIG. 9 , the bushing 20 has a first bushing inner connecting rod intersection SB1 and a second bushing inner connecting rod intersection SB2. The outer peripheral surface 20B of the bushing 20 and the first inner connecting rod longitudinal center line LCA of the first inner connecting rod plate 12 intersect each other at the first bushing inner connecting rod intersection SB1 and the second bushing inner connecting rod intersection SB2 when viewed from the first inner connecting rod axial direction DA. The first bushing inner connecting rod intersection SB1 is arranged closer to the first inner connecting rod transverse center line LCB of the first inner connecting rod plate 12 than the second bushing inner connecting rod intersection SB2. The first inner connecting rod lateral center line LCB is a line perpendicularly intersecting the first inner connecting rod longitudinal center line LCA.

As shown in FIG. 3 , the pin portion 22 is inserted into the first outer link hole 50 and the third outer link hole 60 and passes through the axle bushing hole 20A when the bicycle chain 10 is assembled. The pin portion 22 is preferably 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 portion 23 is inserted into the second outer link hole 54 and the fourth outer link hole 64 and passes through the additional axle bushing hole 26A of the additional axle bushing 26 when the bicycle chain 10 is assembled. The additional pin portion 23 is preferably 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. The pin portion 22 preferably has an outer diameter of 3.6 mm or less, and preferably has an outer diameter of 2.5 mm or more. The additional pin portion 23 preferably has an additional outer diameter of 3.6 mm or less, and preferably has an additional outer diameter of 2.5 mm or more.

The first outer connecting rod piece 16 and the second outer connecting rod piece 18 are connected by the pin portion 22 and the additional pin portion 23. The first inner connecting rod piece 12 and the second inner connecting rod piece 14 are connected by the shaft bushing 20 and the additional shaft bushing 26. The combination of the first inner connecting rod piece 12 and the second inner connecting rod piece 14 is rotatably connected with respect to the combination of the first outer connecting rod piece 16 and the second outer connecting rod piece 18, with the pin portion center axis CY1 of the pin portion 22 and the pin portion center axis CY2 of the additional pin portion 23 as the center. The combined body composed of the first inner connecting rod piece 12 and the second inner connecting rod piece 14 and the combined body composed of the first outer connecting rod piece 16 and the second outer connecting rod piece 18 are alternately arranged and connected in a ring shape.

As shown in FIG. 3, the roller 24 is disposed between the first inner connecting rod piece 12 and the second inner connecting rod piece 14.

The roller 24 has a roller hole 24A for the bushing 20 to be inserted through. The roller 24 can rotate relative to the bushing 20. The additional roller 28 has an additional roller hole 28A for the additional bushing 26 to be inserted through. The additional roller 28 can rotate relative to the additional bushing 26.

The roller 24 is disposed between the first inner connecting rod end 32 of the first inner connecting rod piece 12 and the third inner connecting rod end 42 of the second inner connecting rod piece 14. The additional roller 28 is disposed between the second inner connecting rod end 36 of the first inner connecting rod piece 12 and the fourth inner connecting rod end 46 of the second inner connecting rod piece 14. When the bicycle chain 10 is mounted on the bicycle A, the roller 24 and the additional roller 28 contact the sprocket teeth.

At least one first outer connecting rod chamfered portion 70 is provided on the first outer connecting rod plate 16.

Referring to FIG. 8, the portion where the first outer connecting rod chamfered portion 70 is provided is described.

The first outer connecting rod reference line RA1 is defined as a line extending parallel to the first outer connecting rod transverse direction center line LCF and passing through the first outer connecting rod intersection point SA1. The second outer connecting rod reference line RA2 is defined as a line extending parallel to the first outer connecting rod transverse direction center line LCF and passing through the first outer connecting rod end edge intersection point SC1. The first outer connecting rod end edge intersection point SC1 is the point where the first outer connecting rod longitudinal direction center line LCE of the first outer connecting rod piece 16 and the first outer connecting rod end edge 52A of the first outer connecting rod end portion 52 of the first outer connecting rod piece 16 intersect each other when viewed from the first outer connecting rod axial direction DC.

At least one first outer connecting rod chamfered portion 70 is provided on the first outer connecting rod piece 16 in the first outer connecting rod long side direction DG relative to the first outer connecting rod long side direction center line LCE and is at least partially disposed between the first outer connecting rod reference line RA1 and the second outer connecting rod reference line RA2.

As shown in FIG. 8, at least one first outer connecting rod chamfered portion 70 may also be provided on the second outer connecting rod surface 16B. The second outer connecting rod surface 16B of the first outer connecting rod plate 16 between the first outer connecting rod reference line RA1 and the second outer connecting rod reference line RA2 has a high frequency of contact with the sprocket D of the bicycle A. By providing the first outer connecting rod chamfered portion 70 between the first outer connecting rod reference line RA1 and the second outer connecting rod reference line RA2, the collision between the sprocket D and the first outer connecting rod plate 16 is reduced during gear shifting, so that the movement of the bicycle chain 10 is smoother during gear shifting.

At least one first outer connecting rod chamfered portion 70 may also be provided on the second outer connecting rod end portion 56. At least one first outer connecting rod chamfered portion 70 may also be provided on the second outer connecting rod surface 16B of the second outer connecting rod end portion 56. With this structure, the collision between the sprocket D and the first outer connecting rod plate 16 is reduced, so the movement of the bicycle chain 10 is smoother during gear shifting.

As shown in FIG. 6, at least one first outer connecting rod chamfered portion 70 may also be provided on the first outer connecting rod middle portion 58. At least one first outer connecting rod chamfered portion 70 may also be provided on the first outer connecting rod surface 16A of the first outer connecting rod middle portion 58. With this structure, the sprocket gear can easily enter between the first outer connecting rod plate 16 and the second outer connecting rod plate 18. At least one first outer connecting rod chamfered portion 70 may also be provided on the second outer connecting rod surface 16B of the first outer connecting rod middle portion 58.

As shown in Fig. 9, at least one first inner connecting rod chamfered portion 72 may also be provided on the first inner connecting rod piece 12. The portion where the first inner connecting rod chamfered portion 72 is provided will be described.

The first inner connecting rod reference line RB1 is defined as a line extending parallel to the first inner connecting rod transverse direction center line LCB and passing through the first bushing inner connecting rod intersection SB1. The second inner connecting rod reference line RB2 is defined as a line extending parallel to the first inner connecting rod transverse direction center line LCB and passing through the first inner connecting rod end edge intersection SD1. The first inner connecting rod end edge intersection SD1 is a point where the first inner connecting rod longitudinal direction center line LCA of the first inner connecting rod piece 12 and the first inner connecting rod end edge 32A of the first inner connecting rod end portion 32 of the first inner connecting rod piece 12 intersect each other when viewed from the first inner connecting rod axial direction DA.

At least one first inner connecting rod chamfered portion 72 is provided on the first inner connecting rod piece 12 in the first inner connecting rod longitudinal direction DE relative to the first inner connecting rod longitudinal direction center line LCA and is at least partially disposed between the first inner connecting rod reference line RB1 and the second inner connecting rod reference line RB2.

For example, the first inner link chamfered portion 72 is provided on the first inner link surface 12A of the first inner link end portion 32. The first inner link chamfered portion 72 is provided on the first inner link surface 12A of 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 of the first inner link end portion 32, thereby reducing the possibility that the bicycle chain 10 falls off the sprocket D of the bicycle A at an unforeseen time. Similarly, when the bicycle chain 10 bends during gear shifting, the first inner link surface 12A of the second inner link end 36 is provided with the first inner link chamfer 72, thereby reducing the possibility of the bicycle chain 10 falling off the sprocket D of the bicycle A at an unforeseen time. This allows the bicycle chain 10 to move more smoothly during gear shifting.

As shown in FIG. 5 , at least one second outer connecting rod chamfered portion 74 may be provided on the second outer connecting rod plate 18. At least one second outer connecting rod chamfered portion 74 may be provided on the fourth outer connecting rod surface 18B of the third outer connecting rod end portion 62. At least one second outer connecting rod chamfered portion 74 may be provided on the fourth outer connecting rod surface 18B of the fourth outer connecting rod end portion 66. With this structure, the collision between the sprocket D and the second outer connecting rod plate 18 is reduced during the gear shifting, so that the movement of the bicycle chain 10 is smoother during the gear shifting.

As shown in FIG. 7 , at least one second inner link chamfer 76 may also 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 of the third inner link end 42. The second inner link chamfer 76 is provided on the third inner link surface 14A of the fourth inner link end 46. It is possible to reduce the possibility that the bicycle chain 10 falls off the sprocket D of the bicycle A at an unfavorable time. This allows the bicycle chain 10 to move more smoothly when shifting.

<Second embodiment> A bicycle chain 10 according to a second embodiment is described. The same symbols as those of the first embodiment are given to the structures common to the first embodiment, and repeated descriptions are omitted. The bicycle chain 10 according to the second embodiment preferably has at least a first inner link chamfered portion 72 and a first outer link chamfered portion 70.

At least one first inner connecting rod chamfered portion 72 is provided at the first inner connecting rod end portion 32 of the first inner connecting rod piece 12. Specifically, as shown in FIG. 9 , at least one first inner connecting rod chamfered portion 72 is provided at the first inner connecting rod piece 12 in the first inner connecting rod long direction DE relative to the first inner connecting rod long direction center line LCA and is at least partially disposed between the first inner connecting rod reference line RB1 and the second inner connecting rod reference line RB2.

As shown in FIG. 6 , at least one first inner connecting rod chamfered portion 72 may also be provided on the first inner connecting rod surface 12A. At least one first inner connecting rod chamfered portion 72 may also be provided on the second inner connecting rod end portion 36. At least one first inner connecting rod chamfered portion 72 may also be provided on the first inner connecting rod surface 12A of the second inner connecting rod end portion 36. By providing the first inner connecting rod chamfered portion 72 on the first inner connecting rod surface 12A, it is easy to maintain the engagement between the bicycle chain 10 and the sprocket D when the bicycle chain 10 changes gears. This allows the bicycle chain 10 to move more smoothly when changing gears.

At least one first inner connecting rod chamfered portion 72 may also be provided at the first inner connecting rod middle portion 38. At least one first inner connecting rod chamfered portion 72 may also be provided at the first inner connecting rod surface 12A of the first inner connecting rod middle portion 38. With this structure, the sprocket gear can easily enter between the first inner connecting rod piece 12 and the second inner connecting rod piece 14. At least one first inner connecting rod chamfered portion 72 may also be provided at the second inner connecting rod surface 12B of the first inner connecting rod middle portion 38.

As shown in FIG. 4 , at least one first outer connecting rod chamfered portion 70 may be provided on the first outer connecting rod plate 16. At least one first outer connecting rod chamfered portion 70 may be provided on the second outer connecting rod surface 16B of the first outer connecting rod end portion 52. At least one first outer connecting rod chamfered portion 70 may be provided on the second outer connecting rod surface 16B of the second outer connecting rod end portion 56. With this structure, the collision between the sprocket D and the first outer connecting rod plate 16 is reduced during the gear shifting, so that the movement of the bicycle chain 10 is smoother during the gear shifting.

As shown in FIG. 5 , at least one second outer connecting rod chamfered portion 74 may be provided on the second outer connecting rod plate 18. At least one second outer connecting rod chamfered portion 74 may be provided on the fourth outer connecting rod surface 18B of the third outer connecting rod end portion 62. At least one second outer connecting rod chamfered portion 74 may be provided on the fourth outer connecting rod surface 18B of the fourth outer connecting rod end portion 66. With this structure, the collision between the sprocket D and the second outer connecting rod plate 18 is reduced during the gear shifting, so that the movement of the bicycle chain 10 is smoother during the gear shifting.

As shown in FIG. 7 , at least one second inner link chamfer 76 may also be provided on the second inner link plate 14. The second inner link chamfer 76 is provided on the third inner link surface 14A of the third inner link end 42. The second inner link chamfer 76 is provided on the third inner link surface 14A of the fourth inner link end 46. By providing the second inner link chamfer 76 on the third inner link surface 14A, it is easy to maintain the engagement between the bicycle chain 10 and the sprocket D when the bicycle chain 10 is shifted. This allows the bicycle chain 10 to move more smoothly when shifting.

<Third embodiment> The bicycle chain 10 of the third embodiment is described with reference to Figs. 10 to 13. The same symbols as those of the first embodiment are given to the structures common to the third embodiment, and repeated descriptions are omitted. In the bicycle chain 10 of the third embodiment, the structure of the axle bushing 20 is different 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 connecting rod chamfered portion 70, the first inner connecting rod chamfered portion 72, the second outer connecting rod chamfered portion 74, and the second inner connecting rod chamfered portion 76 shown in the first embodiment may be omitted.

The bushing 20 has an inner peripheral portion 20C that forms a bushing hole 20A. The bushing 20 is inserted through the first inner link hole 30 and the third inner link hole 40 when the bicycle chain 10 is assembled.

The pin portion 22 has an outer peripheral surface 22A, and when the bicycle chain 10 is assembled, the pin portion 22 is inserted through the first outer link hole 50 and the third outer link hole 60 and passes through the axle bushing hole 20A.

In the present embodiment, a metal retaining member 80 is provided between the bushing 20 and the pin portion 22. The metal retaining member 80 is disposed on one of the inner peripheral surface 20C of the bushing 20 and the outer peripheral surface 22A of the pin portion 22. The metal retaining member 80 includes a plurality of retaining holes 80A. The resin member 82 is disposed in the plurality of retaining holes 80A. The resin member 82 is exposed on at least one of the inner peripheral surface and the outer peripheral surface of the metal retaining member 80. The retaining hole 80A includes a through hole, a recessed portion, and a groove portion. In the case where the retaining hole 80A is a groove portion, the retaining hole 80A may also be in a mesh shape, a straight line structure, or a spiral shape.

For example, as shown in Figs. 10 and 11, the metal retaining member 80 is arranged on the inner peripheral surface 20C of the bushing 20. The metal retaining member 80 has a cylindrical shape with the bushing center axis CX of the bushing 20 as the center axis. It is preferred that the inner peripheral surface of the metal retaining member 80 and the inner peripheral surface of the resin member 82 are the same surface. The resin member 82 is exposed on the inner peripheral surface of the metal retaining member 80. The resin member 82 may also be a wear-resistant resin. The resin member 82 is, for example, a phenol resin or a 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 metal. The first material is, for example, iron, aluminum alloy, stainless steel, and titanium alloy. The second material includes metal.

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

As shown in FIG. 12 and FIG. 13, the metal retaining member 84 may be arranged on the outer peripheral surface 22A of the pin portion 22. The metal retaining member 84 has a cylindrical shape with the pin portion center axis CY1 of the pin portion 22 as the center axis. The metal retaining member 84 includes a plurality of retaining holes 84A. The resin member 86 is arranged to be exposed on the outer peripheral surface of the metal retaining member 80.

The pin portion 22 may be formed of a third material, and the metal retaining member 84 may be formed of the third material. The pin portion 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 metal. The third material is, for example, iron, aluminum alloy, stainless steel, and titanium alloy. The fourth material includes metal. The additional pin portion 23 preferably has the same structure as the pin portion 22.

<Fourth embodiment> The bicycle chain 10 of the fourth embodiment will be described with reference to Figs. 14 and 15. The same symbols as those of the first embodiment are given to the structures common to the fourth embodiment, and duplicate descriptions are omitted. The shape of the bicycle chain 10 of the fourth embodiment has parts that are different from the shape of the bicycle chain 10 of the first embodiment, but the descriptions thereof are omitted. In the bicycle chain 10 of the fourth embodiment, the structure of the axle bushing 20 is different 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 includes a bushing hole 20A, a first bushing end portion 90, and a second bushing end portion 92 disposed on the opposite side of the first bushing end portion 90 in the bushing axis direction DJ relative to the bushing center axis CX of the bushing 20. The bushing 20 is inserted into the first inner connecting rod hole 30 and the third inner connecting rod hole 40 by press-fitting in the assembled state of the bicycle chain 10. The first bushing end portion 90 is inserted into the first inner connecting rod hole 30 by press-fitting. The second bushing end portion 92 is inserted into the third inner connecting rod hole 40 by press-fitting.

The bushing 20 includes at least one of a first radial protrusion 94 extending radially outwardly from a first bushing end 90 relative to the bushing center axis CX and a second radial protrusion 96 extending radially outwardly from a second bushing end 92 relative to the bushing center axis CX.

As shown in FIG. 14 , the shaft bushing 20 preferably has 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 a quilting method. The second radial protrusion 96 is formed by a quilting method.

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

The first inner connecting rod piece 12 and the second inner connecting rod piece 14 are firmly connected via the bushing 20 by inserting the bushing 20 into the first inner connecting rod hole 30 and the third inner connecting rod hole 40 , the slit of the first bushing end portion 90 , and the slit of the second bushing end portion 92 .

The pin 22 is inserted into the first outer connecting rod hole 50 and the third outer connecting rod hole 60 by press-fitting. The pin 22 includes a first pin end 100 and a second pin end 102 disposed on the opposite side of the first pin end 100 in the pin axial direction DK relative to the pin center axis CY1. The first pin end 100 is inserted into the first outer connecting rod hole 50 by press-fitting, and is formed around the first outer connecting rod hole 50 by sew-cutting. The second pin end 102 is inserted into the third outer connecting rod hole 60 by press-fitting, and is formed around the third outer connecting rod hole 60 by sew-cutting.

<Variations> The description of each of the above embodiments is an example of the bicycle chain 10 of the present invention and is not intended to limit its form. The bicycle chain 10 of the present invention can take the form of a combination of at least two non-contradictory variations of the above embodiments as shown below. In the following variations, the same symbols as the embodiments are added to the parts that are common to the embodiments, and their descriptions are omitted.

Referring to FIG. 16, a variation of the bicycle chain 10 of the fourth embodiment is described. The first inner link end 32 includes: a first annular axial protrusion 104 surrounding the first inner link hole 30 in the circumferential direction relative to the first inner link center axis AX1. The first annular axial protrusion 104 protrudes toward the second inner link plate 14 along the first inner link axial direction DA when the bicycle chain 10 is assembled. The third inner link end 42 includes: a second annular axial protrusion 106 surrounding the third inner link hole 40 in the circumferential direction relative to the third inner link center 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 assembled.

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 enters the first annular axial protrusion 104 and contacts the first annular axial protrusion 104 when the bicycle chain 10 is assembled. The second bushing end portion 92 of the bushing 20 enters the second annular axial protrusion 106 and contacts 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 radially outwardly from a first bushing end 90 relative to the bushing center axis CX and a second radial protrusion 96 extending radially outwardly from a second bushing end 92 relative to the bushing center axis CX.

The first radial protrusion 94 is formed at the boundary between the first inner connecting rod hole 30 and the second inner connecting rod surface 12B by sewing the outer periphery of the first shaft bushing end portion 90 when the first shaft bushing 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 connecting rod hole 40 and the fourth inner connecting rod surface 14B by sewing the outer periphery of the second shaft bushing end portion 92 when the second shaft bushing end portion 92 is inserted into the second annular axial protrusion 106.

The first inner connecting rod piece 12 and the second inner connecting rod piece 14 are firmly connected via the bushing 20 by inserting the bushing 20 into the first annular axial protrusion 104 and the second annular axial protrusion 106 , the suture of the first bushing end portion 90 , and the suture of the second bushing end portion 92 .

In each of the above-mentioned embodiments and variations, at least one of the following items may also be applied. At least one first outer connecting rod chamfered portion 70 formed on the first outer connecting rod piece 16 may be formed on at least one of the first outer connecting rod surface 16A and the second outer connecting rod surface 16B to extend continuously from the first outer connecting rod end 52 through the first outer connecting rod middle portion 58 to the second outer connecting rod end 56. At least one second outer connecting rod chamfered portion 74 formed on the second outer connecting rod piece 18 may be formed on at least one of the third outer connecting rod surface 18A and the fourth outer connecting rod surface 18B to extend continuously from the third outer connecting rod end 62 through the second outer connecting rod middle portion 68 to the fourth outer connecting rod end 66. At least one first inner connecting rod chamfered portion 72 formed on the first inner connecting rod piece 12 may be formed on at least one of the first inner connecting rod surface 12A and the second inner connecting rod surface 12B to extend continuously from the first inner connecting rod end 32 through the first inner connecting rod middle portion 38 to the second inner connecting rod end 36. At least one second inner connecting rod chamfered portion 76 formed on the second inner connecting rod piece 14 may be formed on at least one of the third inner connecting rod surface 14A and the fourth inner connecting rod surface 14B to extend continuously from the third inner connecting rod end 42 through the second inner connecting rod middle portion 48 to the fourth inner connecting rod end 46. At least one first outer connecting rod chamfered portion 70 formed on the first outer connecting rod piece 16 may be formed on at least one of the first outer connecting rod surface 16A and the second outer connecting rod surface 16B to extend continuously along the entire circumference of the first outer connecting rod piece 16. At least one second outer connecting rod chamfered portion 74 formed on the second outer connecting rod piece 18 may be formed on at least one of the third outer connecting rod surface 18A and the fourth outer connecting rod surface 18B to extend continuously along the entire circumference of the second outer connecting rod piece 18. At least one first inner connecting rod chamfered portion 72 formed on the first inner connecting rod piece 12 may be formed on at least one of the first inner connecting rod surface 12A and the second inner connecting rod surface 12B to extend continuously along the entire circumference of the first inner connecting rod piece 12. At least one second inner link chamfered portion 76 formed on the second inner link piece 14 may be formed on at least one of the third inner link surface 14A and the fourth inner link surface 14B so as to extend continuously along the entire circumference of the second inner link piece 14 .

AX1‧‧‧1st inner connecting rod center axis AX2‧‧‧2nd inner connecting rod center axis AX3‧‧‧3rd inner connecting rod center axis AX4‧‧‧4th inner connecting rod center axis BX1‧‧‧1st outer connecting rod center axis BX2‧‧‧2nd outer connecting rod center axis BX3‧‧‧3rd outer connecting rod center axis BX4‧‧‧4th outer connecting rod center axis C X‧‧‧Axis of the bushing center LCA‧‧‧Centerline of the first inner connecting rod in the long direction LCB‧‧‧Centerline of the first inner connecting rod in the transverse direction LCE‧‧‧Centerline of the first outer connecting rod in the long direction LCF‧‧‧Centerline of the first outer connecting rod in the transverse direction RA1‧‧‧Reference line of the first outer connecting rod RA2‧‧‧Reference line of the second outer connecting rod RB1‧‧‧Reference line of the first inner connecting rod Line RB2‧‧‧Reference line of the second inner link SA1‧‧‧Intersection of the first shaft bushing outer link SA2‧‧‧Intersection of the second shaft bushing outer link SB1‧‧‧Intersection of the first shaft bushing inner link SB2‧‧‧Intersection of the second shaft bushing inner link SC1‧‧‧Intersection of the first outer link end SD1‧‧‧Intersection of the first inner link end 10‧‧‧Bicycle chain 12‧‧‧ 1st inner connecting rod 12A‧‧‧1st inner connecting rod surface 12B‧‧‧2nd inner connecting rod surface 14‧‧‧2nd inner connecting rod 14A‧‧‧3rd inner connecting rod surface 14B‧‧‧4th inner connecting rod surface 16‧‧‧1st outer connecting rod 16A‧‧‧1st outer connecting rod surface 16B‧‧‧2nd outer connecting rod surface 18‧‧‧2nd outer connecting rod 18A‧‧‧3rd outer Connecting rod surface 18B‧‧‧4th outer connecting rod surface 20‧‧‧Axle bushing 20A‧‧‧Axle bushing hole 20B‧‧‧Outer peripheral surface 20C‧‧‧Inner peripheral surface 22‧‧‧Pin part 22A‧‧‧Outer peripheral surface 26‧‧‧Additional shaft bushing 26A‧‧‧Additional shaft bushing hole 30‧‧‧1st inner connecting rod hole 32‧‧‧1st inner connecting rod end 34‧‧‧2nd inner connecting rod Hole 36‧‧‧2nd inner connecting rod end 38‧‧‧1st inner connecting rod middle 40‧‧‧3rd inner connecting rod hole 42‧‧‧3rd inner connecting rod end 44‧‧‧4th inner connecting rod hole 46‧‧‧4th inner connecting rod end 48‧‧‧2nd inner connecting rod middle 50‧‧‧1st outer connecting rod hole 52‧‧‧1st outer connecting rod end 54‧‧‧2nd outer connecting rod hole 56‧‧‧2nd outer connecting rod end 58‧‧‧1st outer connecting rod middle part 60‧‧‧3rd outer connecting rod hole 62‧‧‧3rd outer connecting rod end 64‧‧‧4th outer connecting rod hole 66‧‧‧4th outer connecting rod end 68‧‧‧2nd outer connecting rod middle part 70‧‧‧1st outer connecting rod chamfered part 72‧‧‧1st inner connecting rod chamfered part 74‧‧‧2nd outer connecting rod chamfered part Corner 76‧‧‧Second inner connecting rod chamfer 80‧‧‧Metal retaining member 80A‧‧‧Retaining hole 82‧‧‧Resin member 84‧‧‧Metal retaining member 84A‧‧‧Retaining hole 86‧‧‧Resin member 90‧‧‧First shaft bushing end 92‧‧‧Second shaft bushing end 94‧‧‧First radial protrusion 96‧‧‧Second radial protrusion

FIG. 1 is a schematic diagram of a bicycle viewed from above. FIG. 2 is a partial perspective view of a bicycle chain according to the first embodiment. FIG. 3 is a cross-sectional view of the bicycle chain according to the first embodiment along the III-III line of FIG. 2. FIG. 4 is a side view of the bicycle chain according to the first embodiment viewed from the VA direction of FIG. 2. FIG. 5 is a side view of the bicycle chain according to the first embodiment viewed from the VB direction of FIG. 2. FIG. 6 is a cross-sectional view of the bicycle chain according to the first embodiment along the VI-VI line of FIG. 3. FIG. 7 is a cross-sectional view of the bicycle chain according to the first embodiment along the VII-VII line of FIG. 3. FIG. 8 is a side view of the bicycle chain according to the first embodiment viewed from the VA direction of FIG. 2. FIG. 9 is a cross-sectional view of the bicycle chain of the first embodiment along the IX-IX line of FIG. 3. FIG. 10 is a perspective view and a partially enlarged view of the axle bushing cut along a plane including the center axis of the axle bushing for the bicycle chain of the third embodiment. FIG. 11 is a cross-sectional view of the axle bushing cut along a plane perpendicular to the center axis of the axle bushing. FIG. 12 is a perspective view and a partially enlarged view of the pin portion. FIG. 13 is a cross-sectional view of the pin portion cut along a plane perpendicular to the center axis of the pin portion. FIG. 14 is a cross-sectional view of the bicycle chain of the fourth embodiment. FIG. 15 is a perspective view of a bicycle chain according to the fourth embodiment, wherein the axle bushing is cut along a plane including the center axis of the axle bushing. FIG. 16 is a cross-sectional view of a bicycle chain according to another embodiment.

10‧‧‧Bicycle chain

12‧‧‧1st inner connecting rod

12A‧‧‧1st inner connecting rod surface

12B‧‧‧2nd inner connecting rod surface

14‧‧‧The second inner connecting rod

14A‧‧‧3rd inner connecting rod surface

14B‧‧‧4th inner connecting rod surface

16‧‧‧1st outer connecting rod

16A‧‧‧1st outer connecting rod surface

16B‧‧‧2nd outer connecting rod surface

18‧‧‧The second outer connecting rod

18A‧‧‧3rd outer connecting rod surface

18B‧‧‧4th outer connecting rod surface

20‧‧‧Axle bushing

20A‧‧‧Axle bushing hole

22‧‧‧Sales Department

23‧‧‧Additional sales department

24‧‧‧Roller

24A‧‧‧Roller hole

26‧‧‧Additional shaft bushing

26A‧‧‧Additional shaft bushing hole

28‧‧‧Additional rollers

28A‧‧‧Additional roller hole

30‧‧‧1st inner connecting rod hole

32‧‧‧1st inner connecting rod end

34‧‧‧Second inner connecting rod hole

36‧‧‧End of the second inner connecting rod

38‧‧‧Middle part of the first inner connecting rod

40‧‧‧The third inner connecting rod hole

42‧‧‧End of the third inner connecting rod

44‧‧‧4th inner connecting rod hole

46‧‧‧End of the 4th inner connecting rod

48‧‧‧Middle part of the second inner connecting rod

50‧‧‧1st outer connecting rod hole

52‧‧‧1st outer connecting rod end

54‧‧‧The second outer connecting rod hole

56‧‧‧End of the second outer connecting rod

58‧‧‧Middle part of the first outer connecting rod

60‧‧‧The third outer connecting rod hole

62‧‧‧End of the third outer connecting rod

64‧‧‧The 4th outer connecting rod hole

66‧‧‧End of the 4th outer connecting rod

68‧‧‧Middle part of the second outer connecting rod

AX1‧‧‧1st inner connecting rod center axis

AX2‧‧‧Center axis of the second inner connecting rod

AX3‧‧‧Center axis of the third inner connecting rod

AX4‧‧‧Center axis of the 4th inner connecting rod

BX1‧‧‧1st outer connecting rod center axis

BX2‧‧‧Center axis of the second outer connecting rod

BX3‧‧‧Center axis of the third outer connecting rod

BX4‧‧‧Center axis of the 4th outer connecting rod

CY1, CY2‧‧‧Center axis of the pin

DA‧‧‧Direction of the first inner connecting rod axis

DB‧‧‧Direction of the second inner link shaft

DC‧‧‧1st outer connecting rod shaft direction

DD‧‧‧Direction of the second outer connecting rod shaft

Claims (23)

A bicycle chain comprises: a first inner connecting rod piece, a second inner connecting rod piece, a first outer connecting rod piece, a second outer connecting rod piece, a shaft bushing, and a pin portion; the first inner connecting rod piece comprises: a first inner connecting rod end portion including a first inner connecting rod hole having a first inner connecting rod central axis, a second inner connecting rod central axis extending parallel to the first inner connecting rod central axis, The second inner connecting rod end portion of the second inner connecting rod hole, the first inner connecting rod middle portion connecting the first inner connecting rod end portion and the second inner connecting rod end portion, the first inner connecting rod surface, and the second inner connecting rod surface arranged on the opposite side of the first inner connecting rod surface in the first inner connecting rod axial direction relative to the center axis of the first inner connecting rod; the second inner connecting rod piece includes: a first inner connecting rod having a third inner connecting rod; The third inner connecting rod end portion includes a third inner connecting rod hole at the inner connecting rod center axis, a fourth inner connecting rod end portion includes a fourth inner connecting rod hole having a fourth inner connecting rod center axis extending parallel to the third inner connecting rod center axis, a second inner connecting rod middle portion connecting the third inner connecting rod end portion and the fourth inner connecting rod end portion, and in the assembled state of the bicycle chain, the first inner connecting rod middle portion is connected to the first inner connecting rod middle portion. The third inner connecting rod surface is oriented toward the first inner connecting rod surface of the first inner connecting rod plate in the inner connecting rod axis direction, and the fourth inner connecting rod surface is arranged on the opposite side of the third inner connecting rod surface in the second inner connecting rod axis direction relative to the center axis of the third inner connecting rod; the first outer connecting rod plate is arranged adjacent to the first inner connecting rod plate in the assembled state of the bicycle chain. The invention relates to a method for manufacturing a first outer connecting rod having a first outer connecting rod hole with a first outer connecting rod center axis, a second outer connecting rod end portion having a second outer connecting rod hole extending parallel to the first outer connecting rod center axis, and a method for connecting the first outer connecting rod end portion and the second outer connecting rod end portion. The first outer connecting rod middle portion connected to the first outer connecting rod surface, the second outer connecting rod surface arranged on the opposite side of the first outer connecting rod surface in the first outer connecting rod axis direction relative to the center axis of the first outer connecting rod; the second outer connecting rod plate, in the assembled state of the bicycle chain, is arranged to be adjacent to the second inner connecting rod plate without other inner connecting rod plates or other The outer connecting rod piece includes: a third outer connecting rod end portion including a third outer connecting rod hole having a third outer connecting rod center axis, a fourth outer connecting rod end portion including a fourth outer connecting rod hole having a fourth outer connecting rod center axis extending parallel to the third outer connecting rod center axis, a second outer connecting rod middle portion connecting the third outer connecting rod end portion and the fourth outer connecting rod end portion, The assembled state of the bicycle chain is that the third outer connecting rod surface of the first outer connecting rod surface is oriented toward the first outer connecting rod plate in the axial direction of the first outer connecting rod, and the fourth outer connecting rod surface is arranged on the opposite side of the third outer connecting rod surface in the axial direction of the second outer connecting rod relative to the center axis of the third outer connecting rod; the axle bushing has an axle bushing hole, and the assembly state of the bicycle chain is The shaft bushing is inserted into the first inner connecting rod hole and the third inner connecting rod hole in an assembled state, and the shaft bushing has a first shaft bushing outer connecting rod intersection point and a second shaft bushing outer connecting rod intersection point. The outer peripheral surface of the shaft bushing and the center line of the first outer connecting rod in the long side direction of the first outer connecting rod of the first outer connecting rod plate are observed from the axis direction of the first outer connecting rod. The first shaft bushing outer connecting rod intersection point is arranged at the first outer connecting rod transverse direction center line closer to the first outer connecting rod plate than the second shaft bushing outer connecting rod intersection point. The first outer connecting rod transverse direction center line is a line perpendicularly intersecting the first outer connecting rod longitudinal direction center line and is defined as a line passing through the center axis of the first outer connecting rod and the first outer connecting rod. The pin portion, in the assembled state of the bicycle chain, is inserted into the first outer connecting rod hole and the third outer connecting rod hole and passes through the axle bushing hole. The first outer connecting rod reference line is defined as a line extending parallel to the center line of the first outer connecting rod in the transverse direction and passing through the intersection of the first axle bushing outer connecting rod; the second outer connecting rod The reference line is defined as a line extending parallel to the center line of the first outer connecting rod in the transverse direction and passing through the intersection of the first outer connecting rod end edge, the first outer connecting rod end edge intersection being the first outer connecting rod end of the first outer connecting rod piece when viewed from the axial direction of the first outer connecting rod. At a point where the edges of the first outer connecting rod intersect each other, at least one first outer connecting rod chamfered portion is provided on the first outer connecting rod piece, and in the long-side direction of the first outer connecting rod relative to the center line of the long-side direction of the first outer connecting rod of the first outer connecting rod piece, at least a part of the at least one first outer connecting rod chamfered portion is arranged between the first outer connecting rod reference line and the second outer connecting rod reference line; the first outer connecting rod chamfered portion is not provided at the intersection of the end edges of the first outer connecting rod, in the assembled state of the bicycle chain, in the arranged state of the bicycle chain, the first outer connecting rod piece and the first inner connecting rod piece are arranged so that the center line of the long-side direction of the first outer connecting rod is parallel to the center line of the long-side direction of the first inner connecting rod of the first inner connecting rod piece; in the assembled state of the bicycle chain, in the arranged state of the bicycle chain, the first outer connecting rod piece and the first inner connecting rod piece are arranged so that the center line of the long-side direction of the first outer connecting rod is parallel to the center line of the long-side direction of the first inner connecting rod of the first inner connecting rod piece; The outer periphery of the portion of the first outer connecting rod end portion where the first outer connecting rod chamfered portion is disposed is located further inward than the outer periphery of the portion of the first inner connecting rod end portion corresponding to the first outer connecting rod chamfered portion; the first outer connecting rod chamfered portion is disposed on the first outer connecting rod plate and is arranged closer to the intersection of the first outer connecting rod end edge and the first inner connecting rod end edge. 1. The first external connecting rod has one side portion and another side portion in a direction perpendicular to the center line of the longitudinal direction of the first external connecting rod; the end portion of the first side portion of the chamfered portion of the first external connecting rod on the side of the intersection of the first external connecting rod end edge is located closer to the intersection of the first shaft bushing external connecting rod than the intersection of the second shaft bushing external connecting rod in the longitudinal direction of the first external connecting rod. For example, in the bicycle chain of item 1 of the patent application scope, the portion of the outer peripheral surface of the first outer connecting rod relative to the central axis of the first outer connecting rod, including the intersection of the end edge of the first outer connecting rod, is formed into a flat shape. For example, in the bicycle chain of item 1 of the patent application scope, the at least one first outer connecting rod chamfered portion is disposed on the second outer connecting rod surface. For example, in the bicycle chain of claim 1 or 3, the at least one chamfered portion of the first outer connecting rod is disposed at the end of the second outer connecting rod. For example, in the bicycle chain of item 4 of the patent application scope, the at least one chamfered portion of the first outer connecting rod is disposed on the surface of the second outer connecting rod. For example, in the bicycle chain of item 1 or 3 of the patent application scope, the at least one chamfered portion of the first outer connecting rod is disposed in the middle portion of the first outer connecting rod. For example, in the bicycle chain of item 6 of the patent application scope, the at least one first outer connecting rod chamfered portion is disposed on the first outer connecting rod surface. For example, in the bicycle chain of item 6 of the patent application scope, the at least one chamfered portion of the first outer connecting rod is disposed on the surface of the second outer connecting rod. For example, in the bicycle chain of claim 1 or 3, at least one first inner connecting rod chamfer is provided on the first inner connecting rod plate. As in the bicycle chain of claim 9, the axle bushing has a first axle bushing inner connecting rod intersection and a second axle bushing inner connecting rod intersection, and the outer peripheral surface of the axle bushing and the center line of the first inner connecting rod in the longitudinal direction of the first inner connecting rod of the first inner connecting rod plate intersect each other when viewed from the axis direction of the first inner connecting rod, and the first axle bushing inner connecting rod intersection and the second axle bushing inner connecting rod intersection intersect each other, and the first The shaft bushing inner connecting rod intersection point is arranged at the first inner connecting rod transverse direction center line closer to the first inner connecting rod plate than the second shaft bushing inner connecting rod intersection point. The first inner connecting rod transverse direction center line is a line perpendicularly intersecting the first inner connecting rod longitudinal direction center line. The first inner connecting rod reference line is defined as a line extending parallel to the first inner connecting rod transverse direction center line and passing through the first shaft. The second inner connecting rod reference line is defined as a line extending parallel to the center line of the first inner connecting rod in the transverse direction and passing through the intersection of the first inner connecting rod end edge, and the first inner connecting rod end edge intersection is observed from the axial direction of the first inner connecting rod, so that the center line of the first inner connecting rod in the longitudinal direction of the first inner connecting rod of the first inner connecting rod piece and the first inner connecting rod end of the first inner connecting rod piece are aligned. At the point where the ends of the first inner connecting rods intersect each other, the at least one first inner connecting rod chamfered portion is provided on the first inner connecting rod piece, and in the long side direction of the first inner connecting rod relative to the center line of the long side direction of the first inner connecting rod of the first inner connecting rod piece, at least a part of the at least one first inner connecting rod chamfered portion is arranged between the first inner connecting rod reference line and the second inner connecting rod reference line. For example, in the bicycle chain of claim 1 or 3, at least one second outer connecting rod chamfer is provided on the second outer connecting rod plate. For example, in the bicycle chain of claim 1 or 3, at least one second inner connecting rod chamfer is provided on the second inner connecting rod plate. For example, in the bicycle chain of claim 10, the chamfered portion of the first inner connecting rod is not disposed at the intersection of the first inner connecting rod end edges; in the assembled state of the bicycle chain and in the configuration state of the bicycle chain, the outer periphery of the portion of the first inner connecting rod end where the chamfered portion of the first inner connecting rod is disposed is located further outward than the outer periphery of the portion of the first outer connecting rod end corresponding to the chamfered portion of the first inner connecting rod. For example, in the bicycle chain of claim 13, the chamfered portion of the first inner link is provided on the first inner link plate and is arranged on both sides of a portion on one side and a portion on the other side closer to the intersection of the first inner link end edge in a direction orthogonal to the center line of the longitudinal direction of the first inner link. For example, in the bicycle chain of claim 13, the above-mentioned at least one first inner connecting rod chamfer is provided on the surface of the above-mentioned first inner connecting rod. For example, in the bicycle chain of claim 13, the at least one chamfered portion of the first inner connecting rod is disposed at the end of the second inner connecting rod. For example, in the bicycle chain of claim 16, the at least one first inner connecting rod chamfer is disposed on the first inner connecting rod surface. For example, in the bicycle chain of claim 13, the at least one chamfered portion of the first inner connecting rod is disposed in the middle portion of the first inner connecting rod. For example, in the bicycle chain of claim 18, the at least one first inner connecting rod chamfer is disposed on the first inner connecting rod surface. For example, in the bicycle chain of claim 18, the at least one first inner connecting rod chamfer is disposed on the second inner connecting rod surface. For example, in the bicycle chain of item 13 of the patent application, at least one first outer connecting rod chamfered portion is provided on the first outer connecting rod plate. For example, in the bicycle chain of claim 13, at least one second outer connecting rod chamfer is provided on the second outer connecting rod plate. For example, in the bicycle chain of claim 13, at least one second inner connecting rod chamfer is provided on the second inner connecting rod plate.