The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 23, 2003
Filed:
Jun. 11, 2001
Yasuhiro Yahata, Osaka, JP;
Shimano Inc., Osaka, JP;
Abstract
A chamfered sprocket assembly for facilitating the shifting of a drive chain from a larger sprocket to a smaller sprocket is disclosed. In a preferred embodiment, the chamfered sprocket assembly includes a sprocket having a plurality of chamfered portions on a side facing a smaller sprocket, each chamfered portion located between a pair of toothlike projections located on the rim of the sprocket body. The chamfered portions preferably include a crest which tapers toward a first edge and a second edge of the chamfer portion, respectively. The crest is preferably offset from the center of the chamfer portion toward the driving direction of the sprocket assembly. To further facilitate the shifting of the drive chain, the sprocket preferably includes a rounded shoulder to guide the movement of the drive chain. Finally, the friction between the toothlike projections and the drive chain is reduced by polishing the toothlike projections.