The original method is time-consuming and labor-intensive, so it is urgent to design and manufacture a tool to easily disassemble the bearing to achieve the purpose of timely maintenance of the motor. In view of the two problems encountered in the maintenance of the outer rotor motor, through careful study and discussion, it was decided to adopt the following scheme:
(1) Spacer design
First of all, for the problem that the electric motor cannot support the stressed end of the puller, the method of isolating the wire can be solved. Since the axial force needs to act directly on the axis, the incoming cable can be bent. Therefore, a grooved spacer can be designed, on the one hand, the cable can be led out from the side along the direction of the groove, and on the other hand, the support point of the puller can be directly supported at the surface of the spacer, and at the same time, a circular groove slightly larger than the shaft diameter can be bored on the contact surface of the spacer and the shaft, which can buckle the rotor shaft and ensure that it will not slide during use. After the measurement of the rotor shaft, the shape and size of the specific spacer are determined.
(2) Tension arm design
The gap between the motor bearing and the coil is particularly narrow, and the ordinary bearing puller is too large to extend into the inside of the bearing, and the selection is too small to hook the bearing at all. In order to solve this problem, it is necessary to design a pulling tool that can not damage the coil and have sufficient strength to act on the bearing. In order to make reasonable use of the existing tools, the puller beam and screw part are retained, which not only makes full use of the strength and precision of the professional puller, but also saves material. Before redesigning, the minimum tensile value needs to be measured to determine the specific design plan.
The rotor with bearings is sent to the mechanics laboratory for testing. Through the test of the tensioning force required by the tensile machine for the bearing three times, the force required to pull the bearing down the shaft is 25kN, 23kN and 23kN respectively, so that the minimum force required to pull the bearing down is 25kN.