Multiple sprocket for a bicycle gear shifting mechanism

US6007442A · kind A · utility

Assignee

• SRAM DEUTSCHLAND GmbH · DE

Inventor

• Frank Schmidt · Langenselbold, DE

Key dates

• Filing date: Jan 30, 1998
• Grant date: Dec 28, 1999
• Expiry date: Jan 30, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B62M9/10
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A gearshift mechanism has at least two sprocket wheels on a set of driving sprocket wheels or a set of driven sprocket wheels, having shifting aids to facilitate shifting a chain up and down, it being possible for the shifting to take place under load. The shifting aids include cone rivets, which project axially out of the sprocket wheel plane and are arranged beneath the toothing of the larger one of the at least two sprocket wheels. The at least two sprocket wheels have different numbers of teeth which are selected for having the highest common divisor possible, the purpose of which is to provide as many shifting aids as possible. The positions of the sprocket wheels with respect to one another in the circumferential direction and the position of the shifting aids with respect to the teeth of the larger one of the at least two sprocket wheels are also optimized to ensure a smooth transfer of the chain from one sprocket to another.