Rotor assembly and electric machine

Abstract

The utility model discloses a rotor assembly, rotor assembly includes rotor casing, and its circumference is equipped with the weight-removing groove for reducing weight, is provided with rotor balancing device on rotor casing. The balancing device includes at least one counterweight fastener, and it is installed in the weight-removing groove through the mode of shape cooperation, thereby through the counterweight fastener of detachable, no chippings replaces the conventional punching weight-reducing mode, solves the problem that dynamic balance adjustment efficiency is low, and chippings cleaning is difficult, and the batch production efficiency is improved significantly, is applicable to the motor rotor of high -speed, high dynamic balance requirement. In addition, the utility model is related to the motor with this rotor assembly.

Description

Technical Field

[0001] This utility model relates to a rotor assembly and a motor, and more particularly to a rotor assembly and motor with high dynamic balance requirements. Background Technology

[0002] With the continuous development of new energy-related industries, electric motors are being used more and more. At the same time, various industries and technological fields are placing higher demands on the power and torque density of electric motors, thus requiring increasingly higher motor speeds. As the main moving component within the motor, the dynamic balance accuracy of the motor rotor determines the smoothness of its operation; therefore, its dynamic balance reliability is particularly important.

[0003] In existing technologies, dynamic balancing of motor rotors typically involves drilling holes in the rotor's circumferential surfaces to reduce weight. For example, motor rotors used in hybrid vehicles require multiple weight-reduction holes machined on two circumferential surfaces of the rotor housing for dynamic balancing. However, these motor rotors are usually large, and the initial dynamic imbalance generated during production can reach 2200 g·mm, while the allowable imbalance precision required by the design is extremely high. This necessitates machining a large number of weight-reduction holes to meet the balancing requirements when using the drilling method. This process is not only time-consuming and significantly reduces production efficiency, but the machining debris generated during drilling is also difficult to clean, further increasing the time cost of dynamic balancing and hindering large-scale mass production.

[0004] Therefore, in view of the problems of low efficiency in dynamic balance adjustment of motor rotor and difficulty in debris handling in the existing technology, there is an urgent need for an improved solution that can quickly achieve dynamic balance adjustment and adapt to efficient production. Utility Model Content

[0005] The technical problem to be solved by this invention is to provide an improved rotor assembly that has better dynamic balance performance.

[0006] The aforementioned technical problem is solved by a rotor assembly designed according to this utility model. This rotor assembly has a rotor housing, with weight-reducing grooves arranged circumferentially on the rotor housing for weight reduction. A rotor balancing device for achieving dynamic balance of the rotor assembly is installed on the rotor housing. The rotor balancing device includes at least one counterweight fastener, which is fixed in the weight-reducing groove by form-fitting. This technical solution avoids the drawbacks of traditional drilling weight reduction methods, enables rapid dynamic balance adjustment of the rotor assembly, reduces the time required for dynamic balancing, improves production efficiency, and eliminates the need to handle debris generated during drilling, which is beneficial for mass production.

[0007] According to a preferred embodiment of this utility model, the counterweight fastener of the rotor assembly has an operating end, a fixing part, and a reduced-diameter part located between the operating end and the fixing part along its own axial direction. The outer diameter of the operating end is larger than the width of the weight-removing groove. The reduced-diameter part and the fixing part can pass through the weight-removing groove, and the counterweight fastener is fixed after rotation. This structural design is relatively simple and can be processed based on existing standard parts, reducing manufacturing costs and making the installation and fixing of the counterweight fastener more convenient and stable. Further preferably, the operating end of the rotor assembly has an operating hole for inserting a rotating tool. The setting of the operating hole facilitates the use of tools to rotate the counterweight fastener, improving the convenience of installing and adjusting the counterweight fastener, and enabling more efficient dynamic balance adjustment of the rotor assembly. Additionally, preferably, the fixing part has an extension section protruding relative to the reduced-diameter part, and the extension section is provided with a guide slope for guiding the extension section into the weight-removing groove. The design of the guide slope facilitates the extension section into the weight-removing groove, reduces the resistance during installation, makes the installation of the counterweight fastener smoother, and improves installation efficiency. Since the counterweight fastener needs to be placed into the de-weighting groove, the fixing part has an extension section in one direction or two spaced-apart extension sections. Preferably, the fixing part has two extension sections with guide ramps facing opposite directions to guide the rotation in the same direction. This structural design increases the contact area and engagement stability between the fixing part and the de-weighting groove, further improving the fixing effect of the counterweight fastener in the de-weighting groove and helping to achieve better dynamic balance of the rotor assembly. The two extension sections can be the same or different. It is also preferred that the axial end faces of the two extension sections near the operating end abut against the inner surface of the de-weighting groove housing, and the inclination angle of the guide ramps relative to the axial direction of the counterweight fastener is between 30° and 60°.

[0008] According to a preferred embodiment of this utility model, the method of fixing the counterweight fastener in the rotor assembly further includes fixing the fixing part in the weight-removing groove by bonding or welding. This method further enhances the connection strength between the counterweight fastener and the weight-removing groove, ensuring that the counterweight fastener remains stable under long-term operation and high-speed rotation of the rotor assembly, effectively guaranteeing the long-term reliability of the dynamic balance of the rotor assembly.

[0009] According to a preferred embodiment of this utility model, the rotor assembly has multiple threaded holes in the de-weighting groove, and the fixing part of the counterweight fastener is designed as a threaded screw. This design utilizes a threaded connection to make the connection between the counterweight fastener and the de-weighting groove more secure, better adapting to the high-speed rotation of the rotor assembly, and improving the stability and reliability of the rotor assembly's dynamic balance.

[0010] According to a preferred embodiment of this utility model, the rotor balancing device of the rotor assembly has counterweight holes in the circumferential direction of the rotor housing. The counterweight fastener designed according to this utility model can be used in conjunction with the counterweight holes in the prior art, enabling more flexible adjustment of the dynamic balance of the rotor assembly, further improving the accuracy and effect of dynamic balance adjustment, and ensuring that the rotor assembly maintains a good dynamic balance under different operating conditions.

[0011] Furthermore, the aforementioned technical problems can also be solved by motors equipped with any of the aforementioned rotor assemblies. Due to the optimized rotor assembly design described above, the motor's operational stability is significantly improved, effectively reducing vibration and noise caused by rotor dynamic imbalance, enhancing motor performance and reliability, and extending motor lifespan. Attached Figure Description

[0012] The present invention will now be described in more detail with reference to the accompanying drawings, but this does not limit the overall concept of the invention.

[0013] Figure 1 This is a three-dimensional schematic diagram of a rotor dynamic balancing device in the prior art;

[0014] Figure 2 This is a schematic diagram of the structure of this utility model;

[0015] Figure 3 This is an enlarged schematic diagram of the counterweight fastener;

[0016] Figure 4 This is a schematic diagram of the outer mounting of the counterweight fastener;

[0017] Figure 5 This is a schematic diagram of the inner installation of the counterweight fastener;

[0018] In this invention, unless otherwise specified, "axial," "radial," and "circumferential" are all relative to the rotor. The axial direction of the counterweight fastener refers to the direction of extension of its central axis, while the radial direction of the counterweight fastener is the direction perpendicular to its axial direction. Detailed Implementation

[0019] Figure 1 The diagram illustrates a motor rotor assembly used in a prior art hybrid vehicle, whose dynamic balance is achieved by reducing weight through perforations on two circumferential surfaces 112, 113 of the rotor assembly housing 100. (See diagram for details.) Figure 1As shown, multiple counterweight holes 114 for adjusting dynamic balance are provided on the circumferential surfaces 112 and 113. In addition, weight-reducing grooves 111 for reducing weight are also provided on the circumferential surface of the housing 100. The motor rotor assembly used in hybrid electric vehicles is typically large, resulting in a significant dynamic imbalance during operation, reaching up to 2200 g·mm. The allowable imbalance of the rotor is highly demanding during the design process. Adjusting dynamic balance by drilling holes for weight reduction requires drilling a large number of holes, leading to prolonged dynamic balancing time and low production efficiency. Furthermore, drilling for weight reduction generates machining debris, which is difficult to clean, further increasing the time required for dynamic balancing and hindering mass production.

[0020] Figure 2 This invention illustrates a motor rotor assembly designed according to the present invention. The rotor assembly has a de-weighting slot 11. Compared to the prior art, the de-weighting slot 11 is preferably designed to be narrower. According to an improvement of the present invention, a counterweight fastener 21 is provided in the de-weighting slot 11. By utilizing the existing de-weighting slot 11 and adding the counterweight fastener 21, the dynamic balance of the rotor assembly is achieved, thereby saving the counterweight holes used in the prior art and avoiding the problems mentioned above in the prior art. The specific implementation of the counterweight fastener 21 is described below with reference to embodiments.

[0021] Figure 3 This invention discloses a counterweight fastener 21, which has an operating end 211, a fixing part 212, and a reduced-diameter part 215 located between the operating end 211 and the fixing part 212 along its axial direction. The outer diameter of the operating end 211 is larger than the width of the weight-relief groove 11. The reduced-diameter part and the fixing part can pass through the weight-relief groove, and the counterweight fastener 21 is fixed after rotation. The operating end 211 has an operating hole 213 for inserting a rotating tool, for example... Figure 3 As shown, operating hole 213 is a hexagonal hole, which can be directly operated with a hex wrench. Figure 3 In the illustrated embodiment, the fixing portion 212 is designed with an extension section protruding relative to the reduced diameter portion. The two extension sections extending in opposite directions are symmetrical about the central axis of the counterweight fastener 21. When assembling the counterweight fastener 21, the extension section is first placed into the weight-reducing groove 11. The operating end 211 is rotated using a tool, causing the extension section 216 to rotate 90°, thereby clamping the operating end 211 and the extension section 216 at both ends of the weight-reducing groove 11, thus fixing the counterweight fastener 21. To make it easier for the extension section 216 to engage with the weight-reducing groove 11 during rotation, the extension section preferably has a guide slope 214. During installation, the inner side of the weight-reducing groove 11 contacts the guide slope 214 of the extension section to reduce resistance during rotational installation of the counterweight fastener 21, facilitating installation. Figure 3In the illustrated embodiment, both extension sections 216 are provided with guide ramps 214, and the two guide ramps 214 face opposite directions. The end face of the extension section 216 near the operating end 211 abuts against the inner surface of the housing of the weight-relief groove 11 in the axial direction. The inclination angle of the guide ramps relative to the axial direction of the counterweight fastener is between 30° and 60°. Further preferably, to facilitate the engagement of the counterweight fastener 21 in the weight-relief groove 11, the counterweight fastener 21 is made of a material that readily undergoes elastic deformation, preferably SWRCH35K low-carbon steel.

[0022] Figure 4 and Figure 5 A partial schematic diagram of the counterweight fastener 21 installed in the de-weighting groove 11 is shown from different perspectives. During installation, the fixing part 212 of the counterweight fastener 21 is inserted radially into the de-weighting groove 11 from the outside of the rotor assembly 210. After insertion, the counterweight fastener 21 is rotated 90° in the direction of the guide slope 214 of the extension section 216 using a tightening tool that matches the operating end 211 or the operating hole 213, so that the operating end 211 and the fixing part 212 are clamped and fixed at both ends of the de-weighting groove 11 radially. A schematic diagram after installation is shown below. Figure 4 and 5 As shown, the extension section 216 of the fixing part 212 undergoes elastic deformation, thereby clamping the weight-removing groove 11 with a strong clamping force, making it difficult for the counterweight fastener 21 to fall off when the rotor assembly rotates at high speed. Preferably, after installation, the fixing part 212 can be further fixed to the weight-removing groove 11 by bonding or welding to further enhance the fixing strength.

[0023] By installing counterweight fasteners 21 of different weights on the weight-reducing groove 11, dynamic balancing can be achieved quickly, effectively reducing the imbalance of the rotor assembly. This method also eliminates the need for drilling during dynamic balancing, thus avoiding the need for drilling tools, reducing equipment investment, compressing production costs, and eliminating the need to clean up cutting debris, thereby improving production efficiency.

[0024] Apart from Figure 3 , 4 In the embodiment shown in Figure 5, the counterweight fastener 21 can also be designed in other styles. In another preferred embodiment, multiple threaded holes are provided in the weight-removing groove 11, and the fixing part 212 is designed as a threaded screw. The counterweight fastener 21 is connected to the weight-removing groove 11 by threads, thereby achieving a more secure fixing method. In another preferred embodiment, the extension section 216 extends along one side of the radial direction of the counterweight fastener 21 and does not extend on the other side, or extends asymmetrically on both sides, as long as the counterweight fastener 21 can be fixed in the weight-removing groove 11.

[0025] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

[0026] List of reference numerals

[0027] 1. 100 Rotor Housing

[0028] 11, 111 Deduplication slots

[0029] 112 Rotor assembly housing circumferential surface

[0030] 113 Rotor assembly housing circumferential surface

[0031] 114 counterweight holes

[0032] 2. Rotor balancing device

[0033] 21 Counterweight Fasteners

[0034] 211 Operating end

[0035] 212 Fixing part

[0036] 213 Operating Hole

[0037] 214 Guiding slope

[0038] 215 Reduction section

[0039] 216 Extension Section

Claims

1. A rotor assembly having a rotor housing (1), wherein a weight-reducing groove (11) is provided in the circumferential direction of the rotor housing (1), and a rotor balancing device (2) is provided on the rotor housing (1) for achieving dynamic balance of the rotor assembly, wherein, The rotor balancing device (2) has at least one counterweight fastener (21), which is fixed in the weight-removing groove (11) by a form fit.

2. The rotor assembly according to claim 1, characterized in that, The counterweight fastener (21) has an operating end (211), a fixing part (212), and a reduced diameter part (215) located between the operating end (211) and the fixing part (212) at its two axial ends. The outer diameter of the operating end (211) is larger than the width of the weight-reducing groove (11). The reduced diameter part (215) and the fixing part (212) can pass through the weight-reducing groove (11) and are fixed after rotation.

3. The rotor assembly according to claim 2, characterized in that, The operating end (211) has an operating hole (213) for inserting a rotary tool.

4. The rotor assembly according to claim 2, characterized in that, The fixing part (212) has an extension section (216) that protrudes relative to the reduced diameter part (215), and the extension section (216) is provided with a guide slope (214) for guiding the extension section (216) to engage in the weight-removing groove (11).

5. The rotor assembly according to claim 4, characterized in that, The fixing part (212) has two extension sections (216) spaced apart, and the guide slopes (214) of the two extension sections (216) face opposite directions to achieve guidance in the same rotation direction.

6. The rotor assembly according to claim 5, characterized in that, The end faces of the two extension sections (216) axially near the operating end (211) abut against the inner surface of the housing of the weight-removing groove (11), and the inclination angle of the guide ramp relative to the axial direction of the counterweight fastener is between 30° and 60°.

7. The rotor assembly according to any one of claims 4 to 6, characterized in that, The fastening method of the counterweight fastener (21) also includes fixing the fixing part (212) in the weight-removing groove (11) by bonding or welding.

8. The rotor assembly according to claim 2, characterized in that, The weight removal groove (11) is provided with multiple threaded holes, and the fixing part (212) is designed as a threaded screw.

9. The rotor assembly according to claim 2 or 8, characterized in that, The rotor balancing device (2) has a counterweight hole located in the circumference of the rotor housing (1).

10. An electric motor, characterized in that, The motor has a rotor assembly according to any one of claims 1 to 9.

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