Roller chain idler sprocket units idler pulley units
Roller chain idler sprocket units
INA roller chain idler sprocket units are chain guidance and return units for roller bush chains and roller chains. They compensate chain stretch resulting from operation and improve the smoothness of running of the system at high loads and speeds.
The ready-to-fit units comprise chain sprockets and deep groove ball bearings. The chain sprockets are made from high strength steel, sintered iron or plastic (polyamide). Chain sprockets made from plastic give especially smooth and quiet operation. Since the inner ring of the deep groove ball bearing is extended on both sides, no additional spacer rings are necessary.
In series KSR..BO, the inner ring is locating on the shaft by means of a locking collar. The bearing bore of this series has a plus tolerance. As a result, unmachined shafts up to ISO tolerance h9 can be used under moderate loads and speeds.
Idler pulley units
Idler pulley units are tensioning systems for belt drives and return units. They
- increase the contact angle in belt drives and can therefore transmit higher power values or allow smaller sizes to be used
- compensate for belt stretch resulting from operation
- allow shorter centre distances
- reduce the wear on the belt drive.
The ready-to-fit units comprise deep drawn, profiled sheet steel halves that are riveted together and deep groove ball bearings. Larger diameter pulleys are additionally welded. A lead chamfer on the pulley profile prevents belt damage. Due to the sheet steel construction, the additional rotating masses and imbalances generated are only slight.
Type A is suitable for V-belts, type B for flat belts, V-belts and round belts, type D for round belts as well as steel cables and hemp ropes. | 
