Chain Drive Systems Chains and Sprockets A system

Chain Drive Systems

Chains and Sprockets • A system that uses chains and sprockets for power transmission is referred to as a chain drive. • • Chain: series of interconnected links (typically metal) that form a loop (or not) Sprocket: wheel with evenly spaced teeth located around the edge that engage a chain • Types of chain: roller, silent and ladder • Roller chain is the most commonly used chain type in a chain drive system.

Roller Chains • Synchronous chain that contains roller, pin, and connecting (master) link • Must be lubricated because it wears quickly

Roller Chain • Roller Link: a chain link that consists of two bushings placed inside two rollers that are pressed into two side bars • Side Bar: a steel plate with two precision holes used to connect two pins or two bushings. • Pin Link: a chain link that consists of two steel pins pressed into two side bars with matching holes. The width of a pin link is greater than the width of a roller link • Pin and roller links are alternately joined until the desired chain length is achieved

Connecting/Master Links • Used to connect two ends of a chain to form a loop • Connecting/Master Link: modified pin link that has a removable side bar and retainer • Offset Link: chain link that is used to shorten or lengthen a chain and to connect two ends of a chain • Used for short periods only

Roller Chain • Roller chain is sized by pitch, roller width and roller diameter • Code – Typically two digits (chain and sprocket must match) • • First digit – Pitch in eights of an inch Second digit – Chain type • • • 0 = standard roller 1 = light duty 5 = rollerless chain

Sprockets • Evenly spaced teeth located around its perimeter • A – No hub • B – Integrated hub on one side of sprocket • C – Integrated hub on both sides of sprocket • B and C use key and set screw(s)

Lubrication • Manual or Drip Systems (Type A) • Oil Bath or Oil Slinger (Type B) • Oil Stream or Pump (Type C)

Silent Chain • Consists of a series of links joined together with bushings and pins • Bushing and pin arrangement provides a pivot point for the silent chain • Links are flat on one side and have teeth on the other • Tooth width is determined by the number of plates

Silent Chain Sprockets • A silent chain sprocket has a groove cut in the center of the teeth, preventing the chain from moving laterally during operation • Guide Link: the center link of a silent chain that has no teeth, fits into the groove on the sprocket and keeps the chain properly aligned in the sprocket

Silent Chains • A silent chain is constructed in a manner that allows the chain to ride on the surface of the sprocket. • Silent chain is more expensive than roller chain but has higher operating speeds, is more efficient, runs quieter and smoother, and provides longer life.

Ladder Chain • Light-duty synchronous chain • Commonly used for actuating control functions of equipment, such as speed control • Does not require lubricant because it runs at very low speeds and usually operates intermittently • links are made from precision bent wire with a loop on each end to provide a method for connecting other links