Rotor balance weight for electric machine

Abstract

The utility model relates to the technical field of compressor motor, specifically disclose a rotor balance block for motor, wherein, first layer fixedly arranged on the second layer, and first layer is made of a plurality of first piece body superimposed, second layer is made of a plurality of second piece body superimposed, the magnetic permeability of second piece body is less than the magnetic permeability of first piece body, the height of second layer is h1, the height of balance block main body is H, wherein, h1 and H satisfy: 0 < h1 < H / 3. Such setting, by setting the first layer and second layer of different height, the mass distribution of balance block main body can be flexibly adjusted, realizes accurate dynamic balance. Meanwhile second layer is made of low magnetic permeability material specially, and it can effectively limit rotor leakage flux to pass through balance block main body, thereby significantly reduce eddy current loss, improve motor operating efficiency, and second layer realizes the function of magnetic separation at the same time, because of its height limit, it is helpful to control first layer material, further reduces manufacturing cost.

Description

Technical Field

[0001] This utility model relates to the field of compressor motor technology, and in particular to a rotor balance block for motors. Background Technology

[0002] The rotor balance weight of an electric motor, often referred to as a counterweight or balance plate, is a small metal component primarily mounted on the motor rotor or other rotating parts. Its core function is to correct uneven mass distribution within the rotor. During actual motor operation, dynamic balancing of the rotor effectively eliminates or significantly reduces centrifugal forces caused by uneven mass distribution. This process is crucial for ensuring smooth motor operation, reducing vibration amplitude, lowering noise levels, and extending the lifespan of bearings and the entire motor.

[0003] However, after installation, the existing balance block is subjected to a strong and changing electromagnetic field during motor operation. At this time, the material inside the balance block induces currents in the alternating magnetic field. These currents flow in a closed loop along a path perpendicular to the magnetic field direction, forming so-called eddy currents. As these eddy currents flow within the balance block, they generate heat due to the material's own resistance, i.e., eddy current losses. This eddy current loss not only causes the balance block temperature to rise but also consumes some of the electrical energy originally intended to drive the compressor, resulting in a decrease in the motor's effective output torque. The reduction in effective output torque means that the compressor requires more input power to maintain its original operating state under the same conditions, which to some extent affects the compressor's overall efficiency and increases its energy consumption.

[0004] Therefore, there is an urgent need for a rotor balance block for motors to solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a rotor balance block for motors that can effectively block leakage flux, reduce eddy current losses, and improve motor operating efficiency.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This utility model provides a rotor balance block for an electric motor, including a balance block body. The balance block body includes a first layer and a second layer. The first layer is fixedly disposed on the second layer. The first layer is composed of a plurality of first plates stacked together, and the second layer is composed of a plurality of second plates stacked together. The magnetic permeability of the second plates is less than that of the first plates. The height of the second layer is h1, and the height of the balance block body is H. Wherein, h1 and H satisfy: 0 < h1 < H / 3.

[0008] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the main body of the balance block is arranged in an arc shape, and the main body of the balance block is provided with an inward concave arc surface close to the rotation axis of the motor rotor and an outward convex arc surface away from the rotation axis of the motor rotor.

[0009] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the balance block body is provided with a welding groove along its axial direction. The welding groove includes a first welding slot and a second welding slot. The first welding slot and the second welding slot are both opened on the convex arc surface and / or the concave arc surface. The first welding slot and the second welding slot are both configured to fill the weld formed by laser welding, so as to solidify a plurality of first pieces and a plurality of second pieces into one body to form the balance block body.

[0010] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the width of the first welding groove is D1, wherein D1 satisfies: 1mm≤D1≤5mm.

[0011] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the width of the second welding groove is D2, wherein D1 and D2 satisfy: D1=D2.

[0012] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the cross-sectional shape of the first welding slot and the second welding slot is V-shaped or U-shaped.

[0013] As a preferred technical solution for the rotor balance block of the above-mentioned motor, both the outer convex arc surface and the inner concave arc surface are provided with the first welding groove and the second welding groove.

[0014] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the first welding groove and the second welding groove are symmetrically arranged on the same convex arc surface and the same concave arc surface.

[0015] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the first plate is made of iron material.

[0016] As a preferred technical solution for the rotor balance block of the above-mentioned motor, the second plate is made of stainless steel.

[0017] The beneficial effects of this utility model are as follows:

[0018] This invention provides a rotor balance block for an electric motor. The balance block includes a main body comprising a first layer and a second layer. The first layer is fixedly disposed on the second layer and is composed of several stacked first sheets. The second layer is composed of several stacked second sheets, the permeability of which is less than that of the first sheets. The height of the second layer is h1, and the height of the balance block main body is H, wherein h1 and H satisfy: 0 < h1 < H / 3. This configuration allows for flexible adjustment of the mass distribution of the balance block main body by using first and second layers of different heights, achieving precise dynamic balance. Furthermore, the second layer is made of a low-permeability material, which effectively limits the leakage flux of the motor rotor through the balance block main body, significantly reducing eddy current losses and improving motor operating efficiency. In addition to providing magnetic isolation, the height limitation of the second layer helps control the material of the first layer, further reducing manufacturing costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the rotor balance block for motors provided by this utility model.

[0020] in:

[0021] 100. Balance block body; 101. Concave arc surface; 102. Convex arc surface; 103. First welding groove; 104. Second welding groove;

[0022] 1. First layer; 11. First piece;

[0023] 2. Second layer; 21. Second piece. Detailed Implementation

[0024] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0025] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0026] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1 As shown, this embodiment provides a rotor balance block for a motor. The rotor balance block includes a balance block body 100, which includes a first layer 1 and a second layer 2. The first layer 1 is fixedly disposed on the second layer 2, and the first layer 1 is formed by stacking a plurality of first sheets 11. The second layer 2 is formed by stacking a plurality of second sheets 21. The permeability of the second sheets 21 is less than that of the first sheets 11. The height of the second layer 2 is h1, and the height of the balance block body 100 is H, wherein h1 and H satisfy: 0 < h1 < H / 3. With this configuration, by setting the first layer 1 and the second layer 2 with different heights, the mass distribution of the balance block body 100 can be flexibly adjusted to achieve precise dynamic balance. At the same time, the second layer 2 is specially made of a low permeability material, which can effectively limit the leakage flux of the motor rotor through the balance block body 100, thereby significantly reducing eddy current losses and improving motor operating efficiency. Furthermore, while achieving the magnetic isolation function, the second layer 2, due to its height limitation, helps to control the material of the first layer 1, further reducing manufacturing costs. It should be noted that the height limit of 0 < h1 < H / 3 between h1 and H ensures that costs are reduced to the maximum extent while maintaining good magnetic shielding.

[0030] Furthermore, the first layer 11 is made of iron, and the second layer 21 is made of stainless steel. This arrangement, using a combination of iron and steel layers, further optimizes the magnetic circuit design. The first layer 1, made of magnetically conductive material (iron), can form a good magnetic circuit with the rotor core, which helps guide and utilize magnetic flux, ensuring the electromagnetic performance of the motor. At the same time, combined with the second layer 2, made of magnetically insulating material (stainless steel), it achieves an optimized design that isolates magnetic flux in specific areas and guides magnetic flux in necessary areas.

[0031] It should be noted that stainless steel not only has good magnetic shielding properties, but also excellent mechanical strength and corrosion resistance, which can meet the requirements of the harsh working environment of the motor. Of course, in other embodiments, the second body 21 can also be made of high-strength engineering plastic, which can significantly reduce the weight of the balance block body 100 while achieving magnetic shielding, and has good machinability and insulation.

[0032] Optionally, the balance block body 100 is arc-shaped, and has an inwardly concave arc surface 101 close to the rotation axis of the motor rotor and an outwardly convex arc surface 102 away from the rotation axis of the motor rotor. This configuration allows the inwardly concave arc surface 101 at the front end of the arc-shaped balance block body 100 to match the outer diameter of the motor rotor for precise positioning, saving space and achieving a compact design. The outwardly convex arc surface 102 at the rear end of the balance block body 100 matches the air gap or internal space of the motor, ensuring overall mechanical compatibility and thus achieving overall structural adaptation and functional integration.

[0033] Specifically, this embodiment provides the following technical solution: a plurality of first pieces 11 and a plurality of second pieces 21 are connected by riveting. The balance block body 100 is provided with a welding groove along its axial direction. The welding groove includes a first welding groove 103 and a second welding groove 104. The first welding groove 103 and the second welding groove 104 are both opened on the convex arc surface 102 and / or the concave arc surface 101. The first welding groove 103 and the second welding groove 104 are both configured to fill the weld formed by laser welding, so as to solidify the plurality of first pieces 11 and the plurality of second pieces 21 into one body to form the balance block body 100. This configuration, by introducing laser welding, strengthens the riveting strength between the first layer 1 and the second layer 2. Through laser welding of the first welding groove 103 and the second welding groove 104, several first pieces 11 and several second pieces 21 can be solidified into a robust arc-shaped whole, ensuring the structural integrity and reliability of the balance block body 100 under high-speed rotation, and increasing the natural frequency of the balance block body 100, reducing resonance effects, and avoiding noise generation.

[0034] Optionally, in order to further improve the overall structural connection stability and reliability of the balance block body 100, both the convex arc surface 102 and the concave arc surface 101 are provided with a first welding groove 103 and a second welding groove 104, and the first welding groove 103 and the second welding groove 104 on the same convex arc surface 102 and the same concave arc surface 101 are symmetrically arranged.

[0035] Optionally, in order to reduce solder filling while ensuring a strong weld and thus reduce costs, the width of the first welding groove 103 is D1, wherein D1 satisfies: 1mm ≤ D1 ≤ 5mm. For example, D1 can be 1mm, 2mm, 3mm, 4mm or 5mm.

[0036] Optionally, in order to further improve welding efficiency, the width of the second welding groove 104 is D2, wherein D1 and D2 satisfy: D1=D2.

[0037] Optionally, the cross-sectional shape of the first welding groove 103 and the second welding groove 104 is V-shaped or U-shaped. With this configuration, the V-shaped or U-shaped groove can provide an ideal bevel for laser welding, which facilitates the laser beam to penetrate deeply and ensures that the welding material can be fully filled, thereby obtaining a high-quality weld with greater penetration and fewer defects, which greatly improves the connection strength between the first piece 11 and the second piece 21.

[0038] 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.

Claims

1. A rotor balance block for an electric motor, characterized in that, The system includes a balance block body (100), which includes a first layer (1) and a second layer (2). The first layer (1) is fixedly disposed on the second layer (2), and the first layer (1) is composed of a plurality of first sheets (11) stacked together. The second layer (2) is composed of a plurality of second sheets (21) stacked together. The permeability of the second sheet (21) is less than that of the first sheet (11). The height of the second layer (2) is h1, and the height of the balance block body (100) is H. Wherein, h1 and H satisfy: 0 < h1 < H / 3.

2. The rotor balance block for a motor according to claim 1, characterized in that, The balance block body (100) is arranged in an arc shape, and the balance block body (100) is provided with an inward concave arc surface (101) close to the rotation axis of the motor rotor and an outward convex arc surface (102) away from the rotation axis of the motor rotor.

3. The rotor balance block for a motor according to claim 2, characterized in that, The balance block body (100) has a welding groove along its axial direction. The welding groove includes a first welding slot (103) and a second welding slot (104). The first welding slot (103) and the second welding slot (104) are both opened on the convex arc surface (102) and / or the concave arc surface (101). The first welding slot (103) and the second welding slot (104) are both configured to fill the weld formed by laser welding, so as to solidify a plurality of first pieces (11) and a plurality of second pieces (21) into one body to form the balance block body (100).

4. The rotor balance block for a motor according to claim 3, characterized in that, The width of the first welding groove (103) is D1, wherein D1 satisfies: 1mm≤D1≤5mm.

5. The rotor balance block for an electric motor according to claim 4, characterized in that, The width of the second welding groove (104) is D2, wherein D1 and D2 satisfy: D1=D2.

6. The rotor balance block for a motor according to claim 3, characterized in that, The cross-sectional shape of the first welding groove (103) and the second welding groove (104) is V-shaped or U-shaped.

7. The rotor balance block for a motor according to claim 3, characterized in that, Both the convex arc surface (102) and the concave arc surface (101) are provided with the first welding groove (103) and the second welding groove (104).

8. The rotor balance block for an electric motor according to claim 7, characterized in that, The first welding groove (103) and the second welding groove (104) are symmetrically arranged on the same convex arc surface (102) and the same concave arc surface (101).

9. The rotor balance block for an electric motor according to any one of claims 1-8, characterized in that, The first piece (11) is made of iron.

10. The rotor balance block for an electric motor according to any one of claims 1-8, characterized in that, The second piece (21) is made of stainless steel.

Images