Motor shaft is one of the important parts, as ties of electromechanical energy conversion between motor and equipment, bearing rotating parts, transmission torque, and determine the rotational components of the relative position of the stator. Therefore, the motor shaft must have a reliable strength and stiffness, ensure the realization of the function of presetting design. Shaft type and its applicability to low presence of ladder classification in accordance with the shaft. Can be divided into two kinds of optical axis and the stepped shaft. Optical axis is often made out of cold-drawn round steel, can reduce machining cylindrical shaft working hours, sometimes used in micro motor. Stepped shaft can be convenient, firmly installed many different components, therefore, most of the motor with the shaft. Stepped shaft, depending on the direction of the ladder, and can be divided into one-way ladder shaft (Ladder from one end of the shaft diameter to the other end of the reduced step by step)And two-way ladder shaft (Ladder to both ends step by step from the central part of the shaft diameter decreases)。 Low classification according to the axle billet manufacturing way. Can be divided into round steel shaft (By hot rolled round steel car into the shaft)And forging axis (Made of shaft forgings)And welding axis (Welding spoked to rod axis)。 By hot rolled round steel car into the shaft is one of the most common in small and medium-sized motor shaft. Shaft materials commonly used 45 high quality carbon structural steel. For small power motor, some with Q235 plain carbon steel. Blank diameter should be according to the axis of maximum diameter plus the machining allowance. Therefore, cutting the amount is relatively large. With more than 100 mm in diameter shaft appropriate USES forging shaft. After forging steel, high mechanical strength, and the general form of the forging of the axial, can save raw materials and cutting working hours. For the high mechanical strength requirements of large shaft, such as steam turbine generator shaft, commonly used alloy steel forging. Welding shaft with radial to the rod instead of the rotor bracket, can increase the rotor cavity ventilation area. But when the welding rod, easy to cause the deformation of shaft, must after annealing treatment after welding. On machine tool processing and discontinuous cutting, adverse to the cutting tool. Because of weld, the axial fatigue strength significantly reduced, thus not suitable for high speed motor. Low in the manner of shaft combined with iron core. Can be divided into the middle of the knurling axis, heat to axis and central axis with keyway. Roll rachis small motor for under 10 kw, saves the processing and key work. But when the axial compression into the core, easy to result in deformation of shaft. In the motor running, some of the knurling combined rotor core produce the phenomenon of axial movement. The axial deformation is caused by the core and the shaft with a tight, axial displacement is caused by both the interference fit is enough. Heat set of axis of the middle part is neither knurling, nor with slot. Axis and the core with a certain amount of interference between each hole while core set into the shaft when hot. Selecting the appropriate, as long as the interference of the combination of rotor core and shaft is very reliable. With central slotting shaft and can be divided into with a Duan Jian slot with keyway, two pieces for small motor shaft with a key. Take two pieces of slotting shaft used for large motors. Rotor core (Or bracket)And the shaft is made of key combination. The axial fixation, the end of the core increases with convex shoulder, on the other side with the arc key card of annular keyway in the shaft. The shaft can transfer bigger torque, is often used to power large motors and frequently in the operation of the positive and negative or unfavorable thermal set of motor rotor core. Low classification according to the shape of shaft extension. Can be divided into cylindrical shaft axis, conical shaft axis and axis the reach with half coupling shaft. Cylindrical shaft extension processing is convenient, the motor is used most frequently. Round d shaft and auxiliary stretched out a fastening bolt, processing capacity is larger. But the fittings of the driving wheel loading and unloading convenience, more for special motor. With half coupling shaft and large dc machine is mainly used for hydro-generator. Low classification according to the axis of the shape. Can be divided into solid shaft, deep hole of shaft end zone, and has a hole at the centre of the shaft. The most commonly used in doing solid shaft in the motor. End with deep hole of shaft is mainly used for wound rotor asynchronous motor, so that the rotor on the lead wire through the hole and end cover of the collector ring. A shaft center hole is mainly used for large motors: cold in the dual water turbine generator, the center hole is also as part of the cooling water. 'According to the axial guide magnetic classification. Can be divided into magnetic axis and the magnetic axis. The magnetic axis is mainly used for steam turbine generator. Other motor shaft is usually do not need to permeability. When other classification methods. According to the number of shaft extension is different, can be divided into single shaft axial and biaxial stretching axes; According to the number of the bearing is different, can be divided into single shaft bearings, double bearing and more bearing axis.
