US 6,325,734 B1 · Random engagement roller chain sprocket with staged meshing and flank relief to provide improved noise characteristics

Abstract

A random engagement roller chain sprocket for use primarily in automotive engine chain drive applications which incorporates different asymmetrical tooth profiles for improved noise reduction. In particular, the sprocket includes a first plurality of sprocket teeth each having a first tooth profile including a first engaging flank, a first engaging root, and a first flat positioned between the first engaging flank and first engaging root wherein a first roller initially contacts the first flat at the onset of the first roller meshing with the sprocket. The sprocket also includes a second plurality of sprocket teeth each having a second tooth profile different from the first tooth profile and including a second engaging flank, a second engaging root, and a second flat tangent to the second engaging root remote from the second engaging flank wherein a second roller initially contacts the second flat at the onset of meshing between the second roller and the sprocket.

Claims20

Dependent claims

A sprocket comprising:

a first plurality of teeth each having a first engaging flank and a first disengaging flank that are shaped to define a first tooth profile;
a second plurality of teeth each having a second engaging flank and a second disengaging flank that are shaped to define a second tooth profile different from said first tooth profile;
one of said first plurality of teeth cooperating with a first adjacent tooth to define a first tooth space wherein an associated roller chain roller contacts an engaging flank of said one of the first plurality of teeth when seated in driving contact within said first tooth space;
and
one of said second plurality of teeth cooperating with a second adjacent tooth to define a second tooth space wherein an associated roller chain roller is spaced apart from an engaging flank of said one of the second plurality of teeth to define a clearance therebetween when seated in driving contact within said second tooth space.

2 more elements

A unidirectional roller chain drive system comprising:

a drive sprocket;
a driven sprocket;
a roller chain having rollers in meshing contact with the drive sprocket and the driven sprocket;
and
at least one of the drive sprocket and driven sprocket having a first plurality of teeth with a first engaging flank and a first disengaging flank that are shaped to define a first tooth profile, and a second plurality of teeth with a second engaging flank and a second disengaging flank that are shaped to define a second tooth profile different from said first tooth profile;
one of said first plurality of teeth cooperating with a first adjacent tooth to define a first tooth space wherein an associated roller chain roller contacts an engaging flank of said one of the first plurality of teeth when seated in driving contact within said first tooth space;
and
one of said second plurality of teeth cooperating with a second adjacent tooth to define a second tooth space wherein an associated roller chain roller is spaced apart from an engaging flank of said one of the second plurality of teeth to define a clearance therebetween when seated in driving contact within said second tooth space.

5 more elements

Dependencies are inferred from the claim text.

Random engagement roller chain sprocket with staged meshing and flank relief to provide improved noise characteristics

Life of this patent

Random engagement roller chain sprocket with staged meshing and flank relief to provide improved noise characteristics

Life of this patent

Abstract

Claims20