Machining mainly refers to the machining of metal parts, that is, the machining of parts or semi-finished products with the required geometry, size and surface roughness by cutting off excess parts of the blank with a cutter. Commonly used machining methods include turning, milling, planing, grinding and drilling. The so-called machining technology is to study the dimensional accuracy, installation accuracy and surface roughness of the design requirements economically and efficiently using different machining methods. Ms. Participation today makes a simple summary of the machining process in the motor manufacturing process.

Overview of machining process of motor products

Machining is an important part of the motor manufacturing process. The matching precision, dimensional accuracy and roughness of the motor parts are mainly realized by mechanical processing methods. The level of mechanical processing quality directly affects the quality grade of the motor and meets the design objectives, which has a great influence on the performance and life of the motor. . Among all the machine tools and equipment used in the mass production of small asynchronous motor manufacturers, machining equipment accounts for 40-50%, and mechanical processing accounts for about 25~30% of the total labor required to manufacture motors.

At present, the percentage of machining labor in the motor manufacturing industry is gradually decreasing. This is due to the continuous improvement of the structural structure of the parts and the increasing accuracy of the blank manufacturing, reducing the workload of machining. With the continuous improvement of the performance of metal cutting machine tools and cutting tools, as well as the use of combination machine tools, production lines or automatic production lines, the productivity of machining has been significantly improved, but this does not mean that machining process research in motor manufacturing The role played has become more marginal, and the importance of process plans and routings has become more prominent.

Mechanical parts, such as organic seats, end caps, shafts, rotor supports, rotors, stators, bearing caps, commutators, slip rings, and base plates, housings, and bushings for large motors. How to choose the processing benchmark and processing plan to meet the technical requirements is the basic problem of machining. Here, the characteristics of several large-scale motor parts processing are discussed in detail, and the key elements and their control methods are clarified.

Interchangeability of motor parts

In batch production and mass production of parts, without the selection and repair, arbitrarily take out a part or component of the same specification, it can be smoothly assembled to the product, and the quality of the product can be guaranteed. The nature of such parts or components of the same specification that can be interchanged is referred to as the interchangeability of the parts or components.

Parts are interchangeable and can be professionally produced by specialized workshops or factories, using advanced manufacturing methods to greatly increase labor productivity and reduce product costs. At the same time, assembly time can be shortened and the quality of the assembly can be improved. In terms of repair, when a part or part is damaged, it can be quickly replaced with a new part or part. The greater the scale of production, the more important the interchangeability of components.

In terms of the unit of use, the motor itself is often used as a component or component. First, motors of the same specification are required to be interchangeably installed, and secondly, detachable parts are required to be used interchangeably.

Dimensions related to installation and post-maintenance

● Center height H, the height from the center of the shaft to the plane of the foot;

● shaft extension diameter D and length E, keyway width P and shaft groove depth G;

● The lateral center distance A of the foot hole and its distance from the center line A/2

● The axial center distance B of the foot hole and the distance C from the shoulder to the first foot hole;

● Foot hole diameter K;

● stator inner diameter and rotor outer diameter;

● the fit size of the end cap and the base seat;

● The size of the bearing and the bearing and bearing chamber,

● The size of the outer fan and the outer slip ring and the shaft extension.

Among them, A, B, C, D, H are the main installation dimensions to ensure the interchangeability of the motor; interchangeability is generally achieved by machining.

The characteristics of mechanical machining of motor parts

The machine tools and cutting tools used in the machining of motor parts are not much different from those of general machine manufacturers. However, due to the influence of the structure and electromagnetic performance of the motor, the following characteristics must be paid attention to when machining the motor parts:

● The air gap has a great influence on the performance of the motor. When formulating the machining plan of the motor components, the coaxiality of the components and the reliability of the mating surfaces should be fully paid to ensure the size and uniformity of the air gap.

● Compared with ordinary machine parts, the motor frame and end cover have poor structural rigidity, which is prone to deformation or vibration during clamping and processing, which affects machining accuracy and roughness.

● For parts with integrated materials, such as stators, rotors, commutators and slip rings, it is not possible to use coolants such as oil and soap when machining, and metal chips cannot fall into the insulation to avoid insulation. Deterioration; more should prevent chips from getting stuck in the insulation material, causing insulation damage accidents.

● For magnetically conductive parts, the cutting stress should not be too large to avoid lowering the magnetic permeability and increasing the iron loss.