Chainring

Patent metadata

Field	Value
Publication number	US-9291250-B2
Application number	US-201314102013-A
Country	US
Kind code	B2
Filing date	Dec 10, 2013
Priority date	Dec 6, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A solitary chainring of a bicycle front crankset for engaging a drive chain, including a plurality of teeth formed about a periphery of the chainring, the plurality of teeth consisting of an even number. The plurality of teeth includes a first group of teeth and a second group of teeth arranged alternatingly between the first group of teeth. The first group of teeth and the second group of teeth are equal in number. Each of the first and second group of teeth include an outboard side and an inboard side opposite the outboard side and each tooth of the first group of teeth includes at least a first protrusion on the outboard side thereof and each tooth of the second group of teeth are free of the first protrusions on the outboard side and the inboard side.

First claim

The invention claimed is:

1. A bicycle chainring of a bicycle crankset for engagement with a drive chain, comprising:
a plurality of teeth extending from a periphery of the chainring wherein roots of the plurality of teeth are disposed adjacent the periphery of the chainring;
the plurality of teeth including a first group of teeth and a second group of teeth, each of the first group of teeth wider than each of the second group of teeth; and
at least some of the second group of teeth arranged alternatingly and adjacently between the first group of teeth,
wherein the drive chain is a roller drive chain including alternating outer and inner chain links defining outer and inner link spaces, respectively;
wherein each of the first group of teeth is sized and shaped to fit within one of the outer link spaces and each of the second group of teeth is sized and shaped to fit within one of the inner link spaces; and
wherein a maximum axial width about halfway between a root circle and a top land of the first group of teeth fills at least 80 percent of an axial distance defined by the outer link spaces.

2. The bicycle chainring of claim 1 , wherein each of the first group of teeth fills at least 85 percent of an axial distance defined by the outer link spaces.

3. The bicycle chainring of claim 1 , wherein each of the second group of teeth fills at least 75 percent of an axial distance defined by the inner link spaces.

4. The bicycle chainring of claim 3 , wherein each of the second group of teeth fills at least 80 percent of an axial distance defined by the inner link spaces.

5. The bicycle chainring of claim 4 , wherein each of the second group of teeth fills at least 85 percent of an axial distance defined by the inner link spaces.

6. The bicycle chainring of claim 1 , wherein each of the plurality of teeth includes an outboard side and an inboard side opposite the outboard side and each of the first group of teeth includes at least a first protrusion on one of the outboard side and the inboard side and each of the second group of teeth are free of the first protrusion.

7. The bicycle chainring of claim 6 , wherein each of the first group of teeth includes at least a second protrusion on the other of the outboard and inboard sides.

8. The bicycle chainring of claim 1 for engagement with a roller drive chain having alternating outer and inner chain links defining outer and inner link spaces, respectively, wherein the first group of teeth has a cross-shaped cross section adjacent a top land thereof and adjacent a base thereof;
each of the first group of teeth is sized and shaped to fit within the outer link spaces and each of the second group of teeth is sized and shaped to fit within one of the inner link spaces; and wherein said chainring is configured to guide and maintain the drive chain thereon.

9. The bicycle chainring of claim 8 , wherein the first group of teeth is wider than the inner link spaces.

10. The bicycle chainring of claim 8 , wherein the second group of teeth having a rectangular-shaped cross-section adjacent a top land thereof and adjacent a base thereof.

11. The bicycle chainring of claim 1 , wherein the plurality of teeth consists of an even number; and
wherein each of the first group of teeth are arranged alternatingly between the second group of teeth.

12. A bicycle crankset including the bicycle chainring of claim 1 , the bicycle crankset further comprising:
a crank arm including the single bicycle chainring as the only chainring attached to the crank arm.

13. A bicycle drivetrain including the bicycle chainring of claim 1 , the bicycle drivetrain further comprising:
a plurality of rear hub mounted sprockets; and
a roller drive chain connecting one of the plurality of sprockets to the chainring, the drive chain including alternating outer and inner chain links defining outer and inner link spaces, respectively.

Assignees

• Reiter Markus
• Florczyk Raymond
• Braedt Henrik
• Sram Llc

Inventors

• Reiter Markus
• Florczyk Raymond
• Braedt Henrik

Classifications

• B62M2009/002

  Non-circular chain rings or sprockets · CPC title

• B62M9/08

  involving eccentrically- mounted or elliptically-shaped driving or driven wheel; with expansible driving or driven wheel · CPC title

• Y10T74/2165

  with attached gear · CPC title

• B62M9/105 Primary

  involving front sprocket chain-wheels engaged by the chain, belt or the like · CPC title

• F16H55/30

  Chain-wheels · CPC title