Induction motor rotor and induction motor

Abstract

The utility model relates to an induction motor rotor and an induction motor. The induction motor rotor comprises a rotor core, two end rings and a plurality of conducting bar assemblies. A plurality of conducting bar holes which extend and penetrate in the axial direction of the rotor iron core are formed in the circumferential direction of the rotor iron core at intervals; the two end rings are respectively arranged on two end surfaces of the rotor iron core; a plurality of conducting bar assemblies are arranged, one conducting bar assembly is embedded in each conducting bar hole, each conducting bar assembly comprises a conducting bar and a conducting ring arranged outside the conducting bar in a surrounding mode, and the resistivity of the conducting ring is smaller than that of the conducting bar. According to the invention, the guide ring is arranged outside the guide strip in a surrounding manner, and the resistivity of the guide ring is smaller than that of the guide strip, that is, the material with low resistivity is distributed on the outer side, and the material with high resistivity is distributed on the inner side, so that the characteristics of the material with low resistivity can be greatly utilized when the induction motor rotor runs at a high speed; the loss of the induction motor rotor is effectively reduced, and the efficiency of the induction motor is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric machines, and particularly relates to an induction motor rotor and an induction motor. BACKGROUND

[0002] With the continuous development of asynchronous motors in the industrial market, induction motors in the asynchronous motors form the mainstream. However, the existing induction motor rotor usually adopts low-cost materials such as aluminum, but the high resistivity of aluminum easily leads to high loss of the induction motor rotor, thereby affecting the efficiency of the induction motor. Therefore, how to reduce the loss of the induction motor rotor to improve the efficiency of the induction motor is a technical problem to be solved at present. CONTENT OF THE UTILITY MODEL

[0003] The application provides an induction motor rotor and an induction motor to solve the technical problem of low efficiency of the induction motor caused by high loss of the induction motor rotor.

[0004] To solve the above technical problem, one technical scheme adopted by the application is: an induction motor rotor, comprising: a rotor core, a plurality of bar holes extending through the rotor core in an axial direction are arranged at intervals in a circumferential direction of the rotor core; two end rings, each of which is arranged on an end surface of the rotor core; a plurality of bar assemblies, each of which is embedded in a corresponding bar hole, and each of the bar assemblies comprises a bar and a ring arranged around the bar, wherein the electrical resistivity of the ring is less than that of the bar.

[0005] According to an embodiment of the application, the ring is arranged around the side wall of the bar and covers the side wall completely, and the two end surfaces of the bar are exposed through the two ends of the bar hole.

[0006] According to an embodiment of the application, the ring is a copper ring, and the bar is a cast aluminum bar.

[0007] According to an embodiment of the application, in a vertical plane perpendicular to the axial direction, the bar holes are arranged in a radial direction of the rotor core.

[0008] According to an embodiment of the application, in the radial direction, the diameter of the bar hole gradually decreases from the edge of the rotor core to the center of the rotor core, so that the spacing between two adjacent bar holes is equal.

[0009] According to an embodiment of the application, the end ring and the bar are integrally cast.

[0010] According to an embodiment of the present application, the rotor core is provided with a first through hole penetrating the rotor core, the first through hole is coaxially arranged on the rotor core, and the conductor slot is arranged around the outer periphery of the first through hole; wherein the projection of the end ring on the rotor core in the axial direction covers the conductor slot and is located at the periphery of the first through hole.

[0011] According to an embodiment of the present application, the copper ring is formed by stamping.

[0012] According to an embodiment of the present application, the copper ring comprises: a main body portion; a first tail portion connected to one end of the main body portion; and a second tail portion connected to the other end of the main body portion and bent towards the first tail portion; wherein the first tail portion and the second tail portion at least partially overlap.

[0013] To solve the above technical problems, another technical solution adopted by the present application is: an induction motor comprising the above induction motor rotor.

[0014] The induction motor rotor of the present application comprises a rotor core, two end rings and a plurality of conductor assemblies. The rotor core is provided with a plurality of conductor slots penetrating in the axial direction and arranged at intervals in the circumferential direction; the two end rings are arranged on the two end faces of the rotor core; and each conductor slot is embedded with a conductor assembly, the conductor assembly comprising a conductor and a conductor ring arranged around the conductor, wherein the resistivity of the conductor ring is less than that of the conductor. Since the current frequency on the conductor of the induction motor rotor is also very high when the induction motor rotor is running at high speed, due to the skin effect of the current, the current is concentrated on the surface of the entire conductor when running at high speed, thereby causing high AC loss on the surface of the conductor. Therefore, in the present application, the conductor ring is arranged around the conductor, and the resistivity of the conductor ring is less than that of the conductor, that is, by arranging the material with low resistivity on the outside and the material with high resistivity on the inside, the characteristics of the material with low resistivity can be greatly utilized when the induction motor rotor is running at high speed, thereby effectively reducing the loss of the induction motor rotor and improving the efficiency of the induction motor. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 is a schematic diagram of the overall structure of the induction motor rotor of the present application;

[0017] Figure 2is an exploded structural schematic diagram of the induction motor rotor of the present application;

[0018] Figure 3 is a cross-sectional structural schematic diagram of the induction motor rotor of the present application;

[0019] Figure 4 is a structural schematic diagram of the guide ring of the induction motor rotor of the present application. DETAILED DESCRIPTION

[0020] In order to make the above objectives, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the purpose of description, only the parts related to the present application are shown in the drawings, but not all the structures. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0021] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification are not necessarily all referring to the same embodiment, or to the same alternative embodiment, nor are all alternatives mutually exclusive of one another. It is explicitly contemplated that embodiments described herein can be combined with other embodiments.

[0022] In the description of the present application, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0023] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection or can communicate with each other; it can be directly connected, or indirectly connected through intermediate medium, or the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] The induction motor rotor in the present application can be applied to an induction motor, and the induction motor can be applied to related structures such as vehicles, rail transit or industrial equipment.

[0025] Referring to Figures 1 to 3 , Figure 1 is a schematic diagram of the overall structure of the induction motor rotor of the present application; Figure 2 is a schematic diagram of the exploded structure of the induction motor rotor of the present application; Figure 3 is a schematic diagram of the cross-sectional structure of the induction motor rotor of the present application.

[0026] In one aspect of the present application, an induction motor rotor 10 is provided. The induction motor rotor 10 comprises a rotor core 11, two end rings 12 and a plurality of bar assemblies 13. The rotor core 11 is provided with a plurality of bar holes 111 extending through the rotor core 11 in the axial direction and spaced apart in the circumferential direction of the rotor core 11; the two end rings 12 are respectively arranged on the two end faces of the rotor core 11; and each of the plurality of bar assemblies 13 is embedded in each of the bar holes 111. Each bar assembly 13 comprises a bar 131 and a ring 132 surrounding the bar 131, wherein the electrical resistivity of the ring 132 is less than the electrical resistivity of the bar 131.

[0027] From the above structure, firstly, since the current frequency on the bar 131 of the induction motor rotor 10 is also very high when the induction motor rotor 10 is running at high speed, due to the skin effect of the current, the current is concentrated on the surface of the entire bar 131 when running at high frequency, thereby causing high AC loss on the bar 131. Therefore, in the present application, the ring 132 is arranged outside the bar 131, and the electrical resistivity of the ring 132 is less than the electrical resistivity of the bar 131, that is, the material with low electrical resistivity is distributed on the outside, and the material with high electrical resistivity is distributed on the inside, so that when the induction motor rotor 10 is running at high speed, the characteristics of the material with low electrical resistivity can be greatly utilized to effectively reduce the loss of the induction motor rotor 10, thereby improving the efficiency of the induction motor. 。

[0028] Secondly, the plurality of bar holes 111 are arranged to embed the bar assemblies 13, and the bar assemblies 13 embedded on the rotor core 11 can exhibit good electrical conductivity, thereby reducing the resistance and reducing the energy loss of the induction motor rotor 10; at the same time, the magnetic field formed inside the induction motor rotor 10 can be optimized to make the magnetic field inside the induction motor rotor 10 more uniform, thereby improving the stability and reliability of the induction motor rotor 10. The two end rings 12 are arranged, and the end rings 12 can provide good protection for the rotor core 11 to prevent the rotor core 11 from being damaged by the external environment, and at the same time, the end rings 12 can increase the stability and stiffness of the rotor core 11, thereby reducing the risk of vibration and resonance, and thus making the induction motor rotor 10 more stable when rotating at high speed.

[0029] In some embodiments of the present application, the end ring 12 is made of cast aluminum. Since the price of aluminum is low, using cast aluminum material can effectively reduce the cost of the end ring 12. Alternatively, in some other embodiments, copper, silver, gold, etc. can also be used, and the specific selection can be made according to the actual use scene, which is not limited here.

[0030] In some embodiments of the present application, the guide ring 132 is arranged outside the side wall of the guide bar 131 and completely covers the side wall. The above arrangement can make full use of the low resistivity of the guide ring 132 to reduce the loss of the induction motor rotor 10 and improve the efficiency of the induction motor.

[0031] In some embodiments of the present application, the guide ring 132 is a copper ring and the guide bar 131 is a cast aluminum guide bar. Since aluminum material is low in price and the process is mature, but the aluminum resistivity is high, while the copper material is high in price and the copper melting point is high, it cannot be cast into shape, and can only be welded, so the manufacturing cost is also high, but the resistivity of copper is low. Therefore, the guide bar 131 is set as a cast aluminum guide bar, and the guide ring 132 is set as a copper ring, so that the copper material with low resistivity is distributed on the outside and the aluminum material with high resistivity is distributed on the inside, thereby effectively utilizing the low resistivity of copper material when the induction motor rotor 10 is running at high speed, reducing the loss of the induction motor rotor 10 and effectively improving the efficiency of the induction motor. At the same time, it can also effectively reduce the price of the overall material, thereby reducing the manufacturing cost of the induction motor, and also simplifying the manufacturing process, thereby improving the production efficiency.

[0032] In some other embodiments, the guide ring 132 or the guide bar 131 can also be made of silver or gold, and the specific arrangement can be made according to the actual situation, which is not limited here.

[0033] In some embodiments of the present application, the guide bar hole 111 extends along the radial direction of the rotor core 11 in the axial vertical plane. Compared with the mode that the guide bar assembly 13 is inclined to the remaining direction of the rotor core 11, on the one hand, the current flow path in the guide bar 131 can be made shorter to reduce the resistance and current loss, thereby improving the conductivity efficiency of the guide bar assembly 13; on the other hand, a more uniform and effective magnetic field distribution can be formed, thereby improving the stability of the induction motor rotor 10.

[0034] Preferably, the rotor core 11 is cylindrical, that is, in the axial vertical plane, the cross section of the rotor core 11 is circular. The above arrangement, due to the symmetry of the cylindrical structure, the centrifugal force inside the rotor core 11 is uniform when rotating, and can better withstand the stress generated when rotating at high speed, which is beneficial to improve the reliability and stability of the induction motor rotor 10.

[0035] Alternatively, in some other embodiments, the rotor core 11 can also be in other forms, which will not be described one by one here.

[0036] In some embodiments of the present application, the diameter of the bar hole 111 gradually decreases from the edge of the rotor core 11 to the axis of the rotor core 11 in the radial direction, so that the spacing between the adjacent two bar holes 111 is equal. In the present application, the change of the diameter of the bar hole 111 can facilitate the equal spacing between the adjacent two bar holes 111, which can well improve the consistency of the magnetic circuit of the magnetic field in the induction motor rotor 10, thereby improving the stability of the torque output of the induction motor rotor 10, and further improving the stability of the operation of the induction motor.

[0037] The diameter of the bar hole 111 is the size of the bar hole 111 in the circumferential direction. Therefore, when the size of the bar hole 111 in the circumferential direction gradually decreases in the radial direction, it can be convenient to make the spacing between the adjacent two bar holes 111 equal.

[0038] In some embodiments of the present application, the end ring 12 and the bar 131 are integrally cast into shape. By the integral casting method, on the one hand, the integral casting process is simple, which is beneficial to improve the production efficiency; on the other hand, compared with the form of stacking multiple punching sheets in the prior art, the integral casting method has higher overall structural strength, and the induction motor rotor 10 is not easy to deform when rotating at high speed, which is beneficial to improve the reliability of the induction motor rotor 10.

[0039] In the integral casting of the end ring 12 and the bar 131, high-purity aluminum ingots such as Al 99.5 or Al 99.7 with a resistivity of 0.027-0.03 Ωmm / m at 20℃ can be prepared, then melted to form aluminum liquid, and the aluminum liquid is injected into a special mold to form the bar 131 and the end ring 12 by the die casting process. The above arrangement can integrally cast the end ring 12 and the bar 131 to improve the structural strength of the induction motor rotor 10.

[0040] In some embodiments of the present application, the thickness of the copper ring is 0.5mm-2mm. Since the price of copper is high, when the thickness of the copper ring is greater than 2mm, it will cause the cost of the copper ring to be too high, thereby causing the cost of the induction motor rotor 10 to be too high. When the thickness of the copper ring is less than 0.5mm, the induction motor rotor 10 will generate a lot of heat during rotation, thereby affecting the efficiency of the induction motor. Therefore, when the thickness of the copper ring is 0.5mm-2mm, not only can the cost of the induction motor rotor 10 be reduced, but also the heat generated during the rotation of the induction motor rotor 10 can be reduced, thereby improving the efficiency of the induction motor.

[0041] The thickness of the copper ring can be 0.5mm, 0.7mm, 0.8mm, 1.1mm, 1.3mm, 1.4mm, 1.6mm, 1.9mm, 2mm, etc., which is not limited here.

[0042] Please continue to refer to Figure 2 and Figure 3 In some embodiments of the present application, the rotor core 11 is provided with a first through hole 112 penetrating the rotor core 11, the first through hole 112 is coaxially arranged with the rotor core 11, and the bar hole 111 is arranged around the outer periphery of the first through hole 112. The projection of the end ring 12 on the rotor core 11 along the axial direction of the rotor core 11 covers the bar hole 111 and is located outside the first through hole 112. The arrangement of the first through hole 112 facilitates the arrangement of the bar assembly 13. The projection of the end ring 12 on the rotor core 11 along the axial direction of the rotor core 11 covers the bar hole 111 and is located outside the first through hole 112, so that the end ring 12 can completely cover the bar hole 111, thereby protecting the bar assembly 13 embedded in the bar hole 111.

[0043] In some embodiments of the present application, the copper ring is formed by stamping. The copper ring formed by stamping can increase the strength of the copper ring and improve the reliability of the copper ring. In addition, the stamping forming method is simple in production process and is conducive to improving the overall production efficiency. Furthermore, the stamping forming method can also reduce the production difficulty and production cost.

[0044] Of course, in some other embodiments, the copper ring can also be formed by one-piece forming, which will not be described here.

[0045] Please refer to Figure 4 , Figure 4 is a structural schematic diagram of a guide ring of an induction motor rotor of the present application.

[0046] In some other embodiments, the copper ring comprises a main body portion 1321, a first tail portion 1322 connected to one end of the main body portion 1321, and a second tail portion 1323 connected to the other end of the main body portion 1321 and bent towards the one end of the first tail portion 1322, wherein the first tail portion 1322 and the second tail portion 1323 at least partially overlap. By the above arrangement, compared with the one-piece copper ring, the at least partially overlapping of the first tail portion 1322 and the second tail portion 1323 can also reduce the probability of the existence of a gap in the copper ring, thereby preventing the side wall surface of the cast aluminum bar 131 from being exposed outside and affecting the efficiency of the induction motor rotor 10, and the structure can also improve the structural stability of the copper ring.

[0047] In a second aspect of the present application, an induction motor is provided. The induction motor comprises any of the above induction motor rotors 10. Specifically, since the induction motor comprises the induction motor rotor 10 described in the above embodiments, it also has the beneficial effects of the induction motor rotor 10 described above, which will not be repeated here.

[0048] It should be noted that the terms "horizontal", "vertical", and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined; the terms "parallel", "perpendicular", and the like also do not mean that the fittings must be absolutely parallel or perpendicular, but can form a certain angular deviation. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. In addition, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed during use, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0049] It is to be understood that the terminology "a plurality" herein means "at least two", such as two, three, etc., unless specifically restricted otherwise. In addition, the terms "comprising" and "having", and any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a list of steps or units is not necessarily limited to the listed steps or units, but can optionally further include additional steps or units not listed, or can optionally further include steps or units inherent to such process, method, product, or apparatus. The term "and / or", merely describes an associated relationship between associated objects, and means that there can be three relationships, for example, A and / or B, which means that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects.

[0050] The above description is merely an implementation of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. An induction motor rotor, characterized by, The application relates to an induction motor rotor, comprising: a rotor core, a plurality of bar holes extending through the rotor core in the axial direction are arranged at intervals in the circumferential direction of the rotor core; two end rings, each arranged on an end surface of the rotor core; a plurality of bar assemblies, each of the bar holes is embedded with a bar assembly, the bar assembly comprises a bar and a guide ring arranged outside the bar, wherein the electrical resistivity of the guide ring is less than that of the bar.

2. The induction motor rotor of claim 1, wherein The guide ring is arranged outside the side wall of the bar and covers the side wall completely; the two end surfaces of the bar are exposed through the two ends of the bar hole.

3. The induction motor rotor of claim 1, wherein The guide ring is a copper ring and the bar is a cast aluminum bar.

4. The induction motor rotor of claim 1, wherein In the vertical plane perpendicular to the axial direction, the bar holes are arranged in the radial direction of the rotor core.

5. The induction motor rotor of claim 4, wherein, In the radial direction, the hole diameter of the bar hole gradually decreases from the edge of the rotor core to the axis of the rotor core, so that the interval between two adjacent bar holes is equal.

6. The induction motor rotor of claim 3, wherein The end ring and the bar are integrally cast.

7. The induction motor rotor of claim 1, wherein A first through hole is arranged through the rotor core, the first through hole is coaxial with the rotor core, and the bar hole is arranged around the outer periphery of the first through hole. The projection of the end ring on the rotor core in the axial direction covers the bar hole and is located on the periphery of the first through hole.

8. The induction motor rotor of claim 3, wherein The copper ring is formed by stamping.

9. The induction motor rotor of claim 3, wherein, The copper ring comprises: a main body part; a first tail part connected to one end of the main body part; a second tail part connected to the other end of the main body part and bent towards the first tail part; wherein the first tail part and the second tail part at least partially overlap.

10. An induction motor characterized by, The application further relates to an induction motor rotor comprising any one of the above-mentioned induction motor rotor.

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