Motor and method for improving running reliability of motor

Abstract

The invention relates to the motor technical field, in particular to a motor and a method for improving running reliability of the motor; the motor comprises a bearing external cover, a bearing, a bearing internal cover, and a shaft; the bearing external cover, the bearing and the bearing internal cover are sequentially arranged on the shaft; the bearing is arranged between the bearing external cover and the bearing internal cover; moving clearance is arranged between the end surface of the bearing external ring and the internal spigot of the bearing external cover; the method adopts the design which cancels a waveform spring piece or a bearing spring, leads the moving clearance to exist between the end surface of the bearing external ring and the internal spigot of the bearing external cover, provides a moving space for the bearing, leads the bearing not easy to generate friction with the bearing cover, leads the temperature of the motor not to be excessively high and can prolong the service life of the motor.

Description

Technical field: [0001] The invention relates to the technical field of motors, in particular to a motor and a method for improving the operating reliability of the motor. Background technique: [0002] Electric motors are widely used in industrial production and daily life, and are one of the more important tools. Since most electric motors need long-term and long-term continuous operation, higher requirements are placed on the production quality of electric motors. [0003] For most asynchronous motors, an important factor affecting the quality of use of the motor is the operating temperature of the bearing. If the operating temperature of the bearing is high, the bearing is very easy to be damaged. In practice, the applicant is troubled by the aforementioned problems, especially for H315~ The three-phase asynchronous motor of the 355-2 type is the most serious. [0004] There are many reasons for the temperature rise during the operation of the bearing and the damage to ...

AI Technical Summary

Problems solved by technology

[0006] For example, the problem of radial fit: when the bearing sleeve and the shaft are actually processed, the lower difference is used even to the limit value, which is qualified in actual production. In contrast, the bearing 02 is finished by finishing, and the inner and outer rings of the bearing 02 The tolerance is mostly a few thousandths, which is close to the limit value of the bearing 02 tolerance requirement. In this way, the fit clearance of the outer ring of the bearing 02 will be too small, and the fit of the inner ring of the bearing 02 will be loose; Heat is generated due to friction, so that the temperature rises and the expansion intensifies. However, because the gap between the outer ring of the bearing 02 and the bearing sleeve is too small, the expansion of the bearing 02 is limited, which intensifies the friction between the bearing 02 and the bearing sleeve, and the temperature of the bearing 02 It will continue to rise again until a higher level tends to balance; for the inner ring of bearing 02, because the inner ring of bearing 02 and the bearing sleeve are loosely matched, under the action of high-speed rotating tangential force, it is possible to make the inner ring of the bearing and the shaft 05 Loosening, commonly known as "running the inner ring", running the inner ring will also increase friction and generate heat, resulting in an increase in the temperature of the bearing 02

[0007] High bearing temperature is very unfavorable to bearing operation, it will damage the bearing lubrication, and when the bearing lubrication cannot keep up, the bearing will be burned soon

[0008] Another example is the problem of axial clearance: on the one hand, after the motor is energized and running, both the stator and the rotor will generate heat, which will heat up the motor. Generally, the expansion degree of the rotor is often greater than that of the stator; Considering the deviation of the bearing distance caused by the manufacturing error and tolerance accumulation of the stator and the rotor, in the two-ball bearing structure, except for the fastening end bearing as the positioning, the other bearing must be set as free, that is, to ensure that the bearing can axially Free expansion and contraction, at the same time, two axial clearances need to be considered: if the bearing distance of the shaft is small, it will be blocked by the stop of the inner cover of the bearing, and the thermal expansion of the shaft or manufacturing error will make the bearing distance too large, and the bearing will be blocked by the stop of the outer cover of the bearing ; These two axial clearances are also very important as the radial direction. If they are not done well, the bearing may be blocked or tightened, and then severe friction will cause the bearing temperature to be too high, causing the bearing to fail prematurely.

[0009] Combining the above analysis, it can be seen that the wave spring sheet 03 or bearing spring is added between the free end bearing outer cover 01 of the existing motor and the outer ring of the bearing 02, which limits the bearing and makes the temperature of the bearing too high when the motor is running. exacerbated bearing damage

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