Shimano Inc.

Hideya Inoue

Atsuhiro Emura

Masahiro Yamanaka

Tetsu Nonoshita

Toshio Tetsuka

Yusuke Nishimoto

Koshi Tabe

Shingo Shiraishi

A bicycle sprocket is provided that has a sprocket ring part, a synthetic resin fastening part and at least one attachment part. The synthetic resin fastening part is non-movably coupled to the sprocket ring part at a location radially inwardly of the sprocket teeth relative to the rotation axis. The least one attachment part is at least partially embedded within the synthetic resin fastening part. The attachment part includes a connecting portion and a radial projecting portion extending outwardly from the connecting portion to space the connecting portion radially inward of the sprocket ring part. The attachment part is formed as a separate member from the sprocket ring part and the synthetic resin fastening part. The synthetic resin fastening part facilitates weight saving, while the attachment part prevents the reduction of fastening power (strength) due to deterioration or deformation of the synthetic resin.

Bicycle sprocket

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 shaft component includes an outer tubular member and an inner member non-movably attached to the outer member. The outer tubular member includes a first end portion and a second end portion with an interior longitudinal passageway extending between the first and second end portions. The interior longitudinal passageway has a longitudinal center axis extending through it. The inner member is non-movably attached to the outer tubular member within the interior longitudinal passageway. The outer tubular member is constructed of a first material having a first specific gravity and the inner member is constructed of a second material having a second specific gravity that is lower than the first specific gravity of the first material.

Bicycle shaft component

A bicycle sprocket basically has a metallic sprocket ring part and a synthetic resin fastening part that is configured to ensure that weight can be reduced and that loss of fastening force resulting from deterioration or deformation of the synthetic resin can be prevented. The metallic sprocket ring part includes a ring element with a plurality of sprocket teeth located on an outer periphery of the ring element, a plurality of connecting elements located on an inner periphery of the ring element and a plurality of internal fastening elements located on radial inner ends of the connecting elements, respectively. The synthetic resin fastening part is non-movably formed on both axial faces of the sprocket ring part at a location radially inwardly of the sprocket teeth so as to cover at least a portion of the inner periphery of the ring element, the connecting elements, and the internal fastening elements.

Growing community of inventors

Sakai, Japan

Hideya Inoue