Structure for enhancing strength of motor shaft

Abstract

The utility model relates to a structure for enhancing the strength of a motor shaft. The bearing is arranged on the outer circumference of the shaft in a sleeving manner; the outer circumference of the shaft is sleeved with the positioning ring, the positioning ring is in interference fit with the shaft, and the positioning ring is used for limiting the bearing on the shaft. According to the structure for enhancing the strength of the motor shaft, the annular positioning ring is pressed at the corresponding position of the shaft to ensure the axial positioning of the bearing (the positioning ring is in interference fit with the shaft), and the strength of the shaft is enhanced through the design of the shaft and related connecting pieces under the condition that the overall structure is not changed, so that the stability and the reliability of the motor are improved, and the service life of the motor is prolonged. And meanwhile, the cost is considered, the motor vibration and spark reject ratio is reduced by more than 50% under the same condition, and the motor power fluctuation range is reduced by 30%.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a structure for strengthening the motor shaft. Background Technology

[0002] Motors operate at high speeds, with rated speeds reaching tens of thousands of revolutions per minute. As the medium for power output, the strength of the shaft directly affects a series of issues related to the motor's vibration, noise, and reliability. However, the motor structure is constrained by size, space, and cost limitations, and the shaft diameter cannot be increased indefinitely. Therefore, improving shaft strength under certain constraints is particularly important for enhancing the stability and consistency of the motor. Simultaneously, in recent years, the motor industry has been moving towards smaller size and lighter weight. To achieve this, it is necessary to increase motor power by increasing motor speed, which necessitates further strengthening of the motor shaft to meet this development demand.

[0003] Currently, in the motor industry, to ensure axial positioning of bearings, a groove is typically cut into the shaft to install a shaft retaining ring for axial positioning. Another design uses a stepped shaft, but this type of shaft has significantly higher material and manufacturing costs, and therefore is less commonly used.

[0004] The slotted design on the shaft reduces the shaft diameter; however, it also causes stress concentration at the slotted area. Under high-speed, high-load, and alternating hot and cold operating conditions, this leads to increased shaft deflection, resulting in greater imbalance during operation and creating a vicious cycle. Ultimately, this leads to problems such as decreased motor performance and premature failure.

[0005] Furthermore, axial retaining rings are generally C or E type openings, and their mass distribution along the circumference is uneven. In addition, the axial retaining ring and the shaft groove are loosely fitted (tight fitting will cause them to not fit or the retaining ring to fall off during motor operation, causing the motor to seize up). When the motor rotates at high speed, the opening angle of the axial retaining ring will change, which may cause its mass distribution along the circumference to change. This will cause the mass distribution of the pre-balanced rotor to break the state of the rotor balance after machining. Utility Model Content

[0006] Therefore, the technical problem to be solved by this utility model is to overcome the problem that the gap between the retaining ring and the shaft groove of the motor shaft in the prior art leads to large fluctuations in bearing positioning and large cumulative errors in the motor's related dimensional chain, which in turn affects the motor assembly and performance.

[0007] To solve the above-mentioned technical problems, this utility model provides a structure for strengthening the motor shaft, comprising: a shaft; a bearing, which is sleeved on the outer circumference of the shaft; and a locating ring, which is sleeved on the outer circumference of the shaft, wherein the locating ring is interference-fitted with the shaft, and the locating ring is used to limit the bearing on the shaft. To address the shortcomings of the aforementioned shaft slotting and the addition of C or E type shaft retaining rings, this structure does not involve slotting the shaft or adding C or E type shaft retaining rings. Instead, a circular locating ring is press-fitted at a corresponding position on the shaft to ensure the axial positioning of the bearing (the locating ring is interference-fitted with the shaft).

[0008] In one embodiment of this utility model, the shaft is cylindrical.

[0009] In one embodiment of this utility model, the positioning ring is circular and is coaxial with the shaft.

[0010] In one embodiment of this utility model, the positioning ring has a circular through hole at its center, and the shaft passes through the circular through hole.

[0011] In one embodiment of this utility model, the accuracy of the circular through hole meets the accuracy requirements of GB / T 1800.2, which is grade 7.

[0012] In one embodiment of this utility model, the inner circumference and outer circumference of the positioning ring are concentric.

[0013] In one embodiment of this utility model, the concentricity of the inner and outer circumferences of the positioning ring meets the tolerance requirements of GB / T1184, grade 7.

[0014] In one embodiment of this utility model, the perpendicularity of the end face of the positioning ring meets the grade 7 tolerance requirement of GB / T 1184.

[0015] In one embodiment of this utility model, one end of the shaft is provided with an external thread.

[0016] In one embodiment of this utility model, one end face of the positioning ring is in contact with the bearing.

[0017] Compared with the prior art, the structure for strengthening the motor shaft of this utility model has the following advantages:

[0018] 1. Without changing the overall structure, the strength of the shaft is enhanced through the design of the shaft and its related connecting parts, thereby improving the stability and reliability of the motor, while also taking cost into consideration.

[0019] 2. By solving this bottleneck of shaft strength, the necessary conditions are laid for improving the power density of the motor.

[0020] 3. To solve the problem of large initial balance of the motor rotor and reduce the variation in mass distribution along the circumference of the motor throughout its operation.

[0021] 4. Reduce the cumulative tolerance of motor rotor and related dimensions during assembly to improve the consistency and stability of the motor. Attached Figure Description

[0022] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram of the structure for enhancing the strength of the motor shaft in a preferred embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the shaft and the positioning ring in a preferred embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the positioning ring in a preferred embodiment of the present invention.

[0026] The diagram in the instruction manual is labeled as follows: Shaft 1, Bearing 2, Locating Ring 3, Circular Through Hole 31. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0028] Reference Figure 1 , 2 As shown, the structure for strengthening the motor shaft of this utility model includes: a shaft 1, a bearing 2, and a locating ring 3; the bearing 2 is sleeved on the outer circumference of the shaft 1; the locating ring 3 is sleeved on the outer circumference of the shaft 1, and the locating ring 3 is interference-fitted with the shaft 1. The locating ring 3 is used to limit the bearing 2 on the shaft 1, and one end face of the locating ring 3 is in contact with the bearing 2. By changing the locating ring 3 to an interference fit with the shaft 1, a series of negative effects caused by slotting the shaft and adding C or E type shaft retaining rings are eliminated.

[0029] Reference Figure 3 As shown, the shaft 1 is cylindrical. The mating locating ring 3 is annular and coaxially arranged with the shaft 1. The locating ring 3 has a circular through hole 31 at its center, through which the shaft 1 passes. The interference fit between the locating ring 3 and the shaft 1 must be appropriate to ensure that the locating ring does not shift under axial force and that the shaft does not undergo harmful deformation during pressing. Therefore, the accuracy of the circular through hole 31 meets the accuracy requirements of grade 7 in GB / T 1800.2.

[0030] In the above structure, the inner and outer circumferences of the positioning ring 3 are concentric. The concentricity of the inner and outer circumferences of the positioning ring 3 must be guaranteed; otherwise, it will lead to eccentricity and a large initial balance of the rotor. The concentricity of the inner and outer circumferences of the positioning ring 3 meets the grade 7 tolerance requirements of GB / T 1184. Furthermore, the perpendicularity of the end face of the positioning ring 3 meets the grade 7 tolerance requirements of GB / T 1184.

[0031] In addition, one end of the shaft 1 is provided with an external thread.

[0032] The structure for strengthening the motor shaft of this utility model can achieve the following:

[0033] 1. Batch production verification shows that under the same conditions, the motor vibration and spark failure rate decreases by more than 50%, and the motor power fluctuation range is reduced by 30%;

[0034] 2. Under the same conditions, the lifespan of the motor is extended by more than 30%;

[0035] 3. Under the same conditions, the average value of the initial balance of the motor decreases by 80-120 mg.

[0036] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A structure for strengthening the shaft of a motor, characterized in that, include: axis; A bearing, which is fitted onto the outer circumference of a shaft; A locating ring is fitted on the outer circumference of the shaft and is interference-fitted with the shaft. The locating ring is used to define the bearing on the shaft.

2. The structure for strengthening the motor shaft according to claim 1, characterized in that: The shaft is cylindrical.

3. The structure for strengthening the motor shaft according to claim 2, characterized in that: The positioning ring is circular and is coaxial with the shaft.

4. The structure for strengthening the motor shaft according to claim 3, characterized in that: The positioning ring has a circular through hole at its center, and the shaft passes through the circular through hole.

5. The structure for strengthening the motor shaft according to claim 3, characterized in that: The inner and outer circumferences of the positioning ring are concentric.

6. The structure for strengthening the motor shaft according to claim 2, characterized in that: One end of the shaft is provided with an external thread.

7. The structure for strengthening the motor shaft according to claim 3, characterized in that: One end face of the positioning ring is in contact with the bearing.

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