Several ways of common positioning forms of bearings
The inner and outer rings of the end bearing are fixed in two directions and bear two-way axial force. The bearing at the other end is not fixed axially, allowing the heated expanded shaft to extend freely. Due to different types of bearings, "two-way fixed" and "floating" " The structure of the bearing is also different. Usually, the bearing subjected to the smaller radial force is fixed in both directions to bear the axial force and coordinate the service life of the two bearings; when there is no axial force on the shaft, the bearing subjected to the smaller radial force swims to make the swimming convenient. This positioning method is often used for the shaft with large span or the shaft with high working temperature. How should the bearing be positioned on the shaft and the chassis frame? In the shafting, there are During the operation of some shafts, due to the working load, environment, speed and other problems, the shafts will have thermal expansion and cold contraction in the axial and radial modes; some shafts also need to transfer the load force to the frame because they bear a large axial load. There are three common bearing positioning modes
One way fixing at both ends
This positioning method is that the inner ring of the bearing is fastened on the journal by interference fit, and blocked by the shaft shoulder, and the outer ring of the bearing is blocked by the bearing end cover. The bearings at both ends respectively prevent the one-way movement of the shaft. In order to prevent the bearing from being stuck by the thermal elongation of the shaft, there is a gap of 0.2 ~ 0.3mm between the bearing end cover and the end face of the outer ring of the bearing for the radial bearing; for the radial thrust bearing, there is a gap of 0.2 ~ 0.3mm between the bearing end cover and the shaft A group of gaskets between the bearing seats are used to adjust the internal clearance of the bearing. This positioning method is suitable for the stub shaft with small transmission torque and low working temperature.
Two way fixed at one end and swimming at one end
The inner and outer rings of the bearing at one end are fixed in two directions and bear two-way axial force. The bearing at the other end is not fixed in the axial direction, allowing the heated and expanded shaft to extend freely. Due to the different types of bearings, they are "two-way fixed" and "swimming" "The structure of the bearing is also different. Usually, the bearing subject to the smaller radial force is fixed in both directions to bear the axial force and coordinate the service life of the two bearings; when there is no axial force on the shaft, the bearing subject to the smaller radial force swims to make the swimming convenient. This positioning method is often used for the shaft with large span or the shaft with high working temperature.
Support at both ends
When a pair of herringbone gears mesh, slight axial movement will occur due to manufacturing and installation errors. In order to prevent the gear from getting stuck, the two supports on the small herringbone gear shaft are often designed as swimming mode, and the two supports on the herringbone gear shaft are fixed. When the support of the shaft is sliding bearing, the shaft is positioned axially by the shaft shoulder. When one end needs to be fixed, both sides of the journal at the fixed end are fixed Shoulder or collar, or combination of radial sliding bearing and thrust sliding bearing.
