Sprocket with wear limit indication

• US 20040002402A1
• Filed: 05/14/2003
• Published: 01/01/2004
• Est. Priority Date: 06/28/2002
• Status: Active Grant

• Current Assignee: Tsubakimoto Sprocket Co. (Tsubakimoto Chain Company)
• Original Assignee: Tsubakimoto Sprocket Co. (Tsubakimoto Chain Company)
• Inventors: Nakamura, Kenichiro
• Granted Patent: US 7,018,313 B2
• Time in Patent Office: Days
• US Class Current: 474/156
• CPC Class Codes: F16H 2057/012 of gearings
• CPC Class Codes: F16H 55/30 Chain-wheels

Abstract

In a sprocket for use with a roller chain, a wear limit marker, having a different color from that of the base material of the sprocket, is provided on side surface of a sprocket tooth adjacent to a keyway. The wear limit marker is disposed on an imaginary line extending in the direction of the pressure angle, and is located in a hole or groove provided in a side surface of the sprocket tooth. The marker makes it possible to determine easily and reliably whether or not wear at the location at which wear of a sprocket tooth proceeds most rapidly is within a predetermined limit, and the location of the marker makes it possible to evaluate wear conditions even when the sprocket is installed in a machine.

Claims

1. A sprocket having an axis of rotation, sprocket teeth disposed along an edge of the sprocket spaced radially from said axis of rotation, said sprocket teeth having side surfaces disposed in transverse relationship to the direction of said axis of rotation, and a wear limit indicator for indicating whether or not the sprocket teeth have reached a predetermined wear limit, wherein said wear limit indicator is a wear limit marker disposed on a side surface of one of the sprocket teeth.

2. A sprocket according to claim 1, in which said wear limit marker is disposed on an imaginary line extending in the direction of the pressure angle from a point on the sprocket pitch line at which the center of a chain roller would be located when said chain roller is engaged with, and applying a force to, said one of the sprocket teeth.

3. A sprocket according to claim 1, in which said sprocket has a shaft hole on said axis of rotation, said shaft hole has a keyway for locking said sprocket to a shaft extending into said shaft hole, and said one of the sprocket teeth is a tooth adjacent said keyway.

4. A sprocket according to claim 2, in which said sprocket has a shaft hole on said axis of rotation, said shaft hole has a keyway for locking said sprocket to a shaft extending into said shaft hole, and said one of the sprocket teeth is a tooth adjacent said keyway.

5. A sprocket according to claim 1, in which said sprocket is composed of a base material having a first color, said wear limit marker has a second color different from said first color, and said wear limit marker is fitted into a groove or a hole provided on said side surface of said one of the sprocket teeth.

6. A sprocket according to claim 2, in which said sprocket is composed of a base material having a first color, said wear limit marker has a second color different from said first color, and said wear limit marker is fitted into a groove or a hole provided on said side surface of said one of the sprocket teeth.

7. A sprocket according to claim 3, in which said sprocket is composed of a base material having a first color, said wear limit marker has a second color different from said first color, and said wear limit marker is fitted into a groove or a hole provided on said side surface of said one of the sprocket teeth.

8. A sprocket according to claim 4, in which said sprocket is composed of a base material having a first color, said wear limit marker has a second color different from said first color, and said wear limit marker is fitted into a groove or a hole provided on said side surface of said one of the sprocket teeth.