BELT TENSION PULLEYS
Idler pulley units are tensioning systems for belt drives and idler units. They
increase the wrap angle in belt drives and can therefore support higher power levels or allow smaller units to be used
Compensate for belt stretch resulting from operation
Allow shorter center distances
Reduce the wear on the belt drive
The ready-to-fit units comprise deep drawn, profiled sheet steel pulley halves riveted together and deep groove ball bearings. Pulleys of larger diameters are additionally welded together. A lead chamfer on the pulley profile prevents damage to the belt. Due to the sheet steel construction, the additional rotating masses and the out-of-balance masses generated are low.
Type A is suitable for V-belts, type B for flat, V and round belts, type D for round belts, steel cables and hemp ropes.
Radial insert ball bearings and housing units are robust, ready-to-fit machine elements for the design of economical bearing arrangements. These products have proven effective over many years and are available in many different series. They predominantly comprise a radial insert ball bearing fitted in a housing.
The bore of the housing and the outer ring of the bearing have a spherical profile and are matched to each other. This adjusts the bearing ring in the housing for static shaft misalignments. Thanks to its special mounting type ─ primarily eccentric locking collars or grub screws ─ the radial insert ball bearings are easy to affix onto the shaft. They are particularly easy to fit when they are used in combination with drawn shafts.
The radial insert ball bearings are fitted with multi-piece seals that effectively protect the rolling element set against contamination and moisture, even under difficult and critical operating conditions. Schaeffler offers a wide variety of housing units with radial insert ball bearings. Radial insert ball bearings are based on single-row deep groove ball bearings.
RADIAL INSERT BALL BEARINGS
Radial insert ball bearings are single-row, ready-to-fit units comprising a solid outer ring, an inner ring extended on one or both sides, cages made from plastic or sheet steel and seals of type P, R, L or T. Bearings with an inner ring extended on both sides undergo less tilting of the inner ring and therefore run more smoothly.
The outer ring has a spherical or cylindrical outside surface. In combination with an INA housing matched to the design, bearings with a spherical outside surface can compensate for misalignment of the shaft; see Compensation of misalignments.
They are located on the shaft by means of eccentric locking collars, grub screws in the inner ring, adapter sleeves, drive slots or fit. Radial insert ball bearings are particularly easy to fit and are suitable for drawn shafts of grades h6 to h9 and can be re-lubricated with only a few exceptions.
Some series with eccentric locking collar or grub screws in the inner ring are also available with inch size bore dimensions.
RADIAL INSERT BALL BEARINGS
INA roller chain idler sprocket units are guidance and return units for roller bush chains and roller chains. They can compensate for chain stretch resulting from operation and provide smoother system running under high loads and speeds.
The ready-to-fit units comprise sprockets and deep groove ball bearings. The sprockets are made from high-strength steel, sintered iron or plastic (polyamide). Sprockets made from plastic offer particularly smooth running and generate very little noise. Since the inner ring of the deep groove ball bearing is extended on both sides, no additional spacer rings are required.
In series KSR..B0, the inner ring is located 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.