Types and technical requirements of motor end caps

The motor end cover is a structural part connecting the rotor and the base. On the one hand, the inside of the motor is protected, and on the other hand, the relative position of the stator and the rotor is ensured by the rolling shaft placed in the end cover of the motor. There are many types of motor end caps. From different perspectives, end caps can be divided into various types.

According to the structure of the shaft house, it can be divided into two types: through-eye shaft house motor end cover and stair eye shaft house end cover. When using a through-eye shaft end cap, an external shaft cap must be used to prevent grease leakage. This kind of end cap has the advantages of simple structure, convenient manufacture and convenient maintenance, so it is used the most. The outer part of the measured cover of the stair eye axis acts as an external shaft cover, which reduces the number of parts and simplifies the motor structure. This end cover is used for small motors with a center below 160mm.

According to the motor end cap inventory, it can be divided into welded end caps and cast end caps. Welded end caps are welded from steel plates. Cast end caps can be cast in cast iron, cast steel or aluminum alloys. Cast iron is cheap, has good casting and workability, and has sufficient strength, so cast iron end caps are widely used on small and medium-sized motors. Cast steel end caps or high-strength cast iron end caps are only used in the case of high mechanical strength requirements (such as traction motors and explosion-proof motors). In mass-produced low-power motors, in order to reduce the production time, aluminum alloy die-casting end caps are often used. In order to improve the mechanical strength of the shaft house, the shaft house of the aluminum alloy end cover is built with cast iron lining. Aluminum alloys have poor mechanical strength and wear resistance, and are expensive, so motor end caps with an outer diameter of more than 300 mm are not suitable for use as aluminum alloys.

The structural feature of the motor end cap is that the walls are thin, easily deformed, and it is difficult to make fashionable clips. The end membrane sound is the connector between the sperm and the rotor. According to the fitting accuracy of the lip and the shaft house, the accuracy of the air gap of the motor is guaranteed, and the unloading wear has less influence on the accuracy, so the lip and shaft house must have lower surface roughness.