Shimano Inc.

Shingo Shiraishi

Masahiro Yamanaka

Atsuhiro Emura

Yusuke Nishimoto

Etsuyoshi Watarai

Akinobu Sugimoto

Takashi Furuya

Koshi Tabe

Yoshiaki Ando

Kenichi Akanishi

Toshio Tetsuka

Yuki Hirose

Eigo Kuroiwa

Takuji Tatsumi

Hideya Inoue

A bicycle sprocket comprises a sprocket body, a plurality of sprocket teeth, a mounting member, at least one fastening member, and a cover member. The sprocket body has at least one first threaded portion. The mounting member has at least one fastening hole configured to be aligned with the at least one first threaded portion in the assembled state. The at least one fastening member has a fastening shaft portion, a fastening head portion, and a second threaded portion. The second threaded portion is configured to threadedly engage with the at least one first threaded portion of the sprocket body in the assembled state. The cover member is configured to at least cover the fastening shaft portion of the at least one fastening member when viewed from an axial direction with respect to the rotational center axis in the assembled state.

Bicycle sprocket

A bicycle sprocket includes a sprocket body, a tooth ring, and at least one non-threaded fastener. The sprocket body is made of a first material and has a rotational center axis. A central portion of the sprocket body has a central opening through which the rotational center axis passes. The sprocket body further includes a plurality of arm portions that extend radially outward from the central portion with respect to the rotational center axis. Each arm portion includes a sprocket body attachment portion. The tooth ring is made of a second material different from the first material and includes an annular portion. The annular portion includes a plurality of tooth ring attachment portions and a plurality of chain-driving teeth extending radially outward from the annular portion. The non-threaded fastener fixedly connects a sprocket body attachment portion and to a corresponding tooth ring attachment portion.

A bicycle bottom bracket assembly having a rotational central axis includes a support member, a bearing unit and a radially inward force reducing structure. The support member includes a hanger mounting portion and a bearing mounting portion. The bearing mounting portion is configured to be at least partly positioned within a hanger part of a bicycle frame. The bearing unit includes an outer race, an inner race and at least one roller element disposed between the outer and inner races in a radial direction with respect to the rotational central axis. The outer race is fixed to the bearing mounting portion of the support member. The radially inward force reducing structure reduces a radially inward force being transmitted to the bearing unit.

Bicycle bottom bracket assembly

A bicycle bottom bracket assembly comprises an adapter and a bearing. The adapter has a cylindrical shape and extends along a center axis of the adapter. The adapter comprises a resin material. The bearing comprises rolling elements and an outer race. The outer race is configured to contact the rolling elements and is configured to be provided in the adapter. The outer race is partly embedded in the adapter to be prevented from moving relative to the adapter in both axial directions along the center axis.

A bicycle crank axle assembly has first and second crank arms that are attached to opposite ends of a crank axle. The ends of the crank axle are non-rotatably disposed in axle mounting openings of the first and second crank arms. A first end of the crank axle has at least one axially extending first spline that protrudes radially outward from an outer peripheral surface of its middle body portion. The at least one axially extending first spline non-rotatably couples the crank axle to the first crank arm and prevents outward axial movement of the first crank arm away from the second crank arm. The second end portion of the crank axle has at least one recess that extend radially inward with respect to the outer peripheral surface of the middle body portion to form at least one axially extending second spline.

Bicycle crank axle assembly

A bicycle bottom bracket assembly comprises a first adapter, a first bearing, a second adapter and a second bearing. The first adapter extends along a first center axis of the first adapter. The first bearing comprises first rolling elements and a first outer race. The first outer race is configured to be fitted in the first adapter. The first outer race is slidable relative to the first adapter in both axial directions along the first center axis in a state where the first outer race is fitted in the first adapter. The second adapter extends along a second center axis of the second adapter. The second bearing comprises second rolling elements and a second outer race. The second outer race is configured to be provided in the second adapter such that the second outer race is a separate member from the first outer race.

A bicycle front sprocket has a sprocket body and a chain engagement structure. The sprocket body has a center rotational axis, a first side surface and a second side surface. The second side surface is a smaller sprocket facing side. The chain engagement structure is disposed on an outer periphery of the sprocket body. The chain engagement structure includes a plurality of sprocket teeth extending radially outward from the outer periphery of the sprocket body. The sprocket teeth include at least one first tooth having a first tooth top with a first leading edge and a first trailing edge. The first leading edge is positioned downstream from the first trailing edge with respect to the driving-rotational direction of the bicycle sprocket. The first tooth top is shaped so that the first leading edge is positioned closer to the first side surface than the first trailing edge in the axial direction.

Bicycle front sprocket

A bicycle bottom bracket assembly is provided with a support member, a bearing unit and a seal member. The support member includes a hanger mounting structure and a bearing mounting structure. The bearing unit includes an outer race, an inner race and at least one roller element disposed between the outer and inner races. The outer race is fixed to the bearing mounting structure of the support member. The seal member has a proximal end fixed to the support member and a distal end slidably contacting the inner race of the bearing unit.

A bicycle crank assembly is provided with a crank arm and an axial gap adjustment device. The crank arm has a crank axle mounting part, an extension part extending from the crank axle mounting part, a pedal attachment part provided on a radial outer end of the extension part and a sprocket attachment part. The axial gap adjustment device includes an adjustment adapter and an adjustment member. The adjustment adapter has a crank arm engagement structure that non-rotatably engages the crank arm, a first crank axle opening, and a first screw part. The adjustment member has a second crank axle opening, and a second screw part threadedly engaged with the first screw part to selectively position the adjustment member relative to the adjustment adapter.

Bicycle crank assembly

A bicycle chainring is formed from a first member and an second member. The first member includes a center rotational axis, a crank attachment portion with a plurality of chainring attachment openings and an annular tooth portion with a plurality of chain engaging gear teeth. The second member disposed around the center rotational axis and is fixedly attached to overlie at least one of the crank attachment portion and the annular tooth portion to reinforce the first member without obstructing access to the chainring attachment openings.

Bicycle chainring

A bicycle crank assembly is configured to simplify the work required to adjust the bearing play by the crank assembly when the crank assembly is mounted. The bicycle crank assembly has a left crank that is mounted on a crank axle of the bicycle, and is provided with a crank body and an adjustment member. The crank body includes a crank axle mounting part non-rotatably mounting to one end of the crank axle, an arm part extending from the crank axle mounting part, a pedal mounting part for mounting the pedal and provided at the tip of the arm part, and a male screw part formed on the crank axle mounting part. The adjustment member includes a tubular part having a female screw part into which the male screw part is screwed, and a contact part formed at one end of the tubular part and capable of contacting the bearing supporting the crank axle.

A bicycle bottom bracket assembly is provided with a pair of bearing support members, and a pair of axle bearings so that the bottom bracket assembly is configured and arranged to be mounted into a hanger part of a bicycle frame. The hanger part has opposite open ends. The bearing support members are press-fitted into opposite open ends of the hanger part. The bearings are retained in the bearing support members such that the bearings are disposed inside of the hanger part with outer races of each of the bearings engaging one of the bearing support members. A crank axle is rotatably supported within the hanger part by inner races of the bearings with a first axial end portion of the crank axle being disposed at one end of the hanger part and a second axial end portion of the crank axle being disposed at the other end of the hanger part.

Growing community of inventors

Sakai, Japan

Shingo Shiraishi