IDLER SPROCKETS
Adjustable Idler Sprockets are used to:
• Obtain proper chain tension when either driving or driven shaft is not adjustable. • Guide chain around an obstruction. • Prevent whipping action in the slack span of chain. • Bring about greater chain wrap around a small sprocket, particularly if it is the lower sprocket in a vertical drive. • Take up slack chain caused by normal chain wear. • Provide for reversed direction of rotation of a sprocket in contact with the outside of the chain. Idler sprockets should not rotate at greater speeds than are allowable for drive sprockets of the same diameter. They should be mounted in contact with the “slack” span of chain, whenever possible. Mount them on the outside of the chain when the arc of chain wrap on the smaller sprocket would otherwise be less than 120°. It is advisable that idler sprockets have at least three teeth in mesh with the chain. Inside mounted idlers usually account for quieter operation, especially if sprocket to sprocket centers are short and speed is moderately high.
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STYLES LTB Bronze Bushed Idler
LTB
Ball Bearing Idler
204
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