Key sprocket drive system

A key sprocket drive system for a conveyor belt, comprising:

• (a) a drive drum having a generally circular outer surface for rotation about an axis;
• (b) a key system having at least two set screws adapted to engage a drive pin that is positioned in an axial groove along said outer surface of said drive drum;
• (c) a metal contoured collar having an inner surface and an outer surface presenting pin receiving body portions between said inner and outer surfaces at selected positions about said inner surface, said pin receiving body portions adapted to receive said set screws, and contact said outer surface of said drive drum at said selected positions, and defining gaps between said inner surface of said metal contoured collar and said outer surface of said drive drum between said pin receiving body portions;
• and
• (d) a plastic sprocket having a generally annular configuration with externally facing teeth at spaced intervals, said plastic sprocket adapted to receive said set screws;
• wherein said set screws engage said drive pin thereby securing said plastic sprocket and said metal contoured collar to said drive drum, and said teeth engage said conveyor belt.

A method of assembling a key sprocket drive system for a conveyor belt, comprising

• (a) positioning on a drive drum having an outer surface, a contoured collar having an inner surface and an outer surface said inner surface of said collar sized presenting pin receiving body portions at selected positions to contact said outer surface of said drum;
• (b) positioning a sprocket member having a generally annular configuration with externally facing teeth at spaced intervals, around said contoured collar;
• (c) securing said sprocket member and said contoured collar to said drive drum by a securement means adapted to engage said sprocket member and said contoured collar thereby engaging said outer surface of said drive drum;
• (d) defining gaps between said pin receiving body portions and said inner surface of said contoured collar and said outer surface of said drive drum when said pin receiving body portions contact to said outer surface of said drive drum at said selected positions;
• and
• engaging said conveyor belt with said teeth engage for driving said conveyor belt.

A key sprocket drive system comprising:

• (a) a drive roller having a generally cylindrical outer surface for rotation about an axis;
• (b) a collar co-axially mounted to said drive roller, said collar having:
• (i) an outer surface,
• (ii) an inner surface
• (A) for contact with said outer surface of said drive roller at selected radial positions;
• (B) spaced from said outer surface of said drive roller between said selected radial positions to define a gap between said outer surface of said drive roller and said inner surface of said collar;
• (c) a sprocket separate from said collar having a generally annular configuration co-axially mounted to said collar, said sprocket having teeth extending radially outwardly;
• (d) securement means to releaseably secure said sprocket, collar, and roller at said selected radial positions.