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The article \"Discussing the Differences in Bearing Loads between Vertical and Horizontal Motors\" explains the distribution of bearing loads in vertical and horizontal motors, helping readers understand which bearings bear the axial and radial loads at the motor shaft ends, as well as the weight of the motor rotor. So, which bearing bears the torque load of the motor? Changhui Instruments explains in this article how to take into account the influence of motor power or torque on the load when calculating the load on motor bearings. yunrun.com.cn/tech/3277.html 1. Coupling load: Let’s consider this in several different scenarios. First, the motor connected via a coupling (taking a horizontal motor as an example): As can be seen in the diagram, the coupling transmits mechanical torque to the motor, while the electromagnetic torque on the rotor inside the motor balances the torque of the external load. It is precisely because these two torques are in balance that no other torque is applied between them. From the perspective of load, the circumferential force at any radial section on the coupling is balanced by a circumferential force of equal magnitude but opposite direction on the other side. If we represent the cross-section in the front-view direction as a top view, it can be seen that the circumferential force, at that diameter cross-section, is equivalent to the radial force of the bearing. As shown in the figure below: It can be seen from the graph that the two radial loads are of equal magnitude but in opposite directions. Therefore, overall, the load on the coupling does not exert a radial load on the bearing system. 2. Pulley load: If the motor shaft is connected to a pulley load, then from a torque perspective, it is still the torque transmitted by the pulley that balances the electromagnetic torque generated within the motor. However, the tension on the side of the pulley is relatively high during operation, while the other end is relatively loose. Therefore, the tension of the pulley constitutes a radial load. At this point, this minimum tension force is related to torque. The torque transmitted by the pulley should equal the tension force multiplied by the bearing radius. The magnitude of this tension is related to the pulley radius, as well as to the torque. Assume the tension forces of the two belts are F1 and F2. If the torque is T, then: T = F1 × r – F2 × r, and the radial load on the bearing is the difference between F1 and F2. 3. Gears directly on the shaft end: If gears are installed directly on the motor shaft end, they are subjected to circumferential loads during meshing, while there is no corresponding load at the other end. At this point, this clamping force becomes a load on the shaft assembly. This gripping force is related to the torque transmitted. The calculations in this regard are further divided into two cases: spur gears and helical gears. The overall calculation approach is the same as that for pulley loads; the torque transmitted by gears equals the circumferential load multiplied by the pitch circle radius. This torque balances the electromagnetic torque generated within the motor, but these circumferential forces constitute the radial forces on the motor’s bearing system. For helical gears, corresponding axial forces are also generated. Conclusion ◆ In motors with coupling loads, the load on the bearing system is not affected by torque. ◆In motors with pulley loads, the load on the bearing system is affected by the pulley tension and, indirectly, by the torque. (Because torque and pulley radius determine the minimum tension) ◆ Gear load and bearing system load are affected by torque. After understanding the overall load conditions on motor bearing systems, how can we calculate the load on each bearing within a motor shaft system? Visit Shangchanghui Instrument Network to learn more