In-cell rotor, electric machine and method for manufacturing in-cell rotor

Abstract

The invention provides an embedded rotor which comprises a first permanent magnet which is configured to be a cylinder, is integrally formed and is provided with a plurality of interval grooves in the circumferential direction, and the first permanent magnet is divided into a plurality of first permanent magnet sub-parts by the interval grooves; the second permanent magnets are arranged in the interval grooves; wherein the interval groove is used for accommodating the magnetic field applying device in the orienting and magnetizing process, so that the first permanent magnet obtains permanent magnetism; wherein the first permanent magnet sub-parts have magnetic field directions extending in the radial direction, and the first permanent magnet sub-parts on the two sides of the interval grooves have opposite magnetic field directions; the magnetic field direction of the second permanent magnet extends in the circumferential direction. And the magnetic fields of the second permanent magnets in the interval grooves and the magnetic fields of the first permanent magnets on the two sides of the interval grooves form a continuous magnetic circuit with the shortest path. The invention further relates to an electric machine comprising the in-cell rotor and to a method for producing the in-cell rotor.

Description

Technical Field

[0001] The present disclosure relates to an inline rotor, an electric machine including the inline rotor, and a method for manufacturing the inline rotor. Background Art

[0002] Current embedded rotors consist of magnetizers and permanent magnets. The magnetizers are formed by stacking stamped silicon steel sheets, and the permanent magnets are embedded within the magnetizers. The silicon steel sheets that make up the magnetizers can be, for example, non-oriented or oriented silicon steel sheets. Non-oriented silicon steel sheets have very little difference in magnetic permeability or magnetic properties in all directions, meaning there is no directional difference. However, oriented silicon steel sheets have differences in magnetic permeability or magnetic properties in different directions, meaning they have excellent magnetic permeability in certain directions but poorer permeability in other directions.

[0003] When the embedded rotor's magnetizer uses non-oriented silicon steel sheets, the magnetization depth of the magnetizer is insufficient. When using oriented silicon steel sheets, the magnetization of the magnetizer is uneven due to the specific orientation of the silicon steel sheets. Furthermore, the magnetizer itself is non-magnetic, which results in wasted rotor space, underutilization of the rotor space, and failure to maximize the rotor's magnetic flux. Summary of the Invention

[0004] The present disclosure proposes an embedded rotor, which can effectively increase the magnetization depth of the rotor, thereby improving the performance of the rotor and the motor having the rotor.

[0005] The present disclosure proposes an embedded rotor, which includes: a first permanent magnet, which is constructed as a cylinder and is integrally formed, and a plurality of spacing grooves are arranged inside the first permanent magnet along the circumferential direction, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; a second permanent magnet, which is arranged in the spacing grooves; wherein the spacing grooves are used to accommodate a magnetic field application device during the orientation and magnetization process, so that the first permanent magnet obtains permanent magnetism; wherein the first permanent magnet sub-portions have a magnetic field direction extending along the radial direction of the first permanent magnet, and the first permanent magnet sub-portions on both sides of the spacing groove have opposite magnetic field directions respectively; wherein the magnetic field direction of the second permanent magnet extends along the circumferential direction of the first permanent magnet; and wherein the magnetic field of the second permanent magnet in the spacing groove together with the magnetic field of the first permanent magnet on both sides of the spacing groove form a continuous magnetic circuit with the shortest path.

[0006] In an embodiment according to the present disclosure, the outer circumferential surface of the first permanent magnet is a closed surface.

[0007] In an embodiment according to the present disclosure, the spacing groove penetrates the first permanent magnet along a longitudinal direction of the first permanent magnet.

[0008] In an embodiment of the present disclosure, the material of the first permanent magnet is plastic ferrite.

[0009] In an embodiment according to the present disclosure, the second permanent magnet is sintered or bonded.

[0010] In an embodiment according to the present disclosure, the second permanent magnet is made of one or more of ferrite, neodymium iron boron, samarium iron nitrogen, and samarium cobalt.

[0011] In an embodiment according to the present disclosure, a cross section of the second permanent magnet is configured as a trapezoid.

[0012] In an embodiment of the present disclosure, a lower base of the trapezoidal cross section is close to the center of the cross section of the first permanent magnet.

[0013] In an embodiment according to the present disclosure, a positioning portion is provided in the spacing groove, and the positioning portion is used to fix the second permanent magnet in the spacing groove.

[0014] In an embodiment according to the present disclosure, the positioning portion is arranged in the spacing groove on a side close to the center of a cross section of the first permanent magnet.

[0015] In an embodiment according to the present disclosure, the positioning portion is configured as a protrusion for abutting against and fixing the second permanent magnet.

[0016] In an embodiment of the present disclosure, an air slot is provided between the second permanent magnet arranged in the spacing slot and the first permanent magnet on a side facing the center line of the first permanent magnet.

[0017] The present disclosure also provides a motor, which includes the embedded rotor described above according to the embodiment of the present disclosure.

[0018] The present disclosure also proposes a method for manufacturing an embedded rotor, the method comprising: manufacturing a first permanent magnet, wherein the first permanent magnet is constructed as a cylinder and is integrally formed, a plurality of spacing grooves are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; arranging a first magnetic field application device in the spacing grooves, and orienting the first permanent magnet so that the first permanent magnet sub-portions on both sides of the spacing grooves respectively have orientations in opposite directions along the radial direction of the first permanent magnet; manufacturing a second permanent magnet; orienting the second permanent magnet so that the orientation of the second permanent magnet extends along the circumferential direction of the first permanent magnet; arranging the second permanent magnet in the spacing grooves; magnetizing the first permanent magnet and the second permanent magnet according to the orientation of the first permanent magnet and the orientation of the second permanent magnet, so that the magnetic field of the second permanent magnet in the spacing grooves and the magnetic field of the first permanent magnets on both sides of the spacing grooves together form a continuous magnetic circuit with the shortest path.

[0019] In an embodiment according to the present disclosure, manufacturing the first permanent magnet includes: manufacturing the first permanent magnet in an integral manner by injection molding.

[0020] The present disclosure also proposes a method for manufacturing an embedded rotor, the method comprising: manufacturing a first permanent magnet, wherein the first permanent magnet is constructed as a cylinder and is integrally formed, a plurality of spacing grooves are arranged inside the first permanent magnet along the circumferential direction, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; arranging a first magnetic field application device in the spacing grooves, and orienting the first permanent magnet so that the first permanent magnet sub-portions on both sides of the spacing grooves respectively have orientations in opposite directions along the radial direction of the first permanent magnet; magnetizing the first permanent magnet according to the orientation of the first permanent magnet; manufacturing a second permanent magnet; orienting the second permanent magnet so that the orientation of the second permanent magnet extends along the circumferential direction of the first permanent magnet; magnetizing the second permanent magnet according to the orientation of the second permanent magnet; arranging the second permanent magnet in the spacing grooves; wherein the magnetic field of the second permanent magnet in the spacing grooves and the magnetic fields of the first permanent magnets on both sides of the spacing grooves together form a continuous magnetic circuit with the shortest path.

[0021] In the prior art, rotor magnets are typically formed by stamping and stacking silicon steel sheets. However, the magnetization depth of non-oriented silicon steel sheets is generally insufficient, while the magnetization direction of oriented silicon steel sheets is fixed, resulting in uneven magnetization depth after magnetization. Furthermore, manufacturing and assembling silicon steel sheets according to a desired orientation, such as that described in the embodiments of this disclosure, is inherently complex and costly.

[0022] Compared with the prior art, the embedded rotor according to the present invention adopts a first permanent magnet instead of a magnetizer. The first permanent magnet itself is magnetic and can provide additional magnetic flux. The rotor can therefore provide more magnetic flux, and a synchronous motor with such a rotor can obtain greater power and stronger performance. In the embedded rotor according to the present invention, a magnetic field application device, such as a strong magnetic device, can be arranged in the spacing slots in the first permanent magnet to orient and magnetize the first permanent magnet, so that the first permanent magnet obtains a desired magnetic field, for example, a deep orientation depth and magnetization depth in the radial direction of the first permanent magnet. In addition, the one-piece first permanent magnet is made of magnetic material, and preferably a magnetic material with low magnetic resistance and good magnetic permeability can be selected, and the processing technology of the one-piece first permanent magnet is simple, saves materials, is low in cost, and is very suitable for industrial mass production.

[0023] Hereinafter, the best embodiment for implementing the present disclosure will be described in more detail with reference to the accompanying drawings so that the features and advantages of the present disclosure can be easily understood. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some exemplary embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0025] Figure 1 shows a perspective view of an embedded rotor according to an embodiment of the present disclosure,

[0026] Figure 2 FIG. 1 shows an exploded perspective view of an inline rotor according to an embodiment of the present disclosure.

[0027] Figure 3 FIG2 shows a schematic diagram of the magnetic field direction of the first permanent magnet of the embedded rotor according to an embodiment of the present disclosure.

[0028] Figure 4 FIG2 shows a schematic diagram of the magnetic field direction of the second permanent magnet of the embedded rotor according to an embodiment of the present disclosure.

[0029] Figure 5 FIG2 shows a schematic diagram of a magnetic circuit of an embedded rotor according to an embodiment of the present disclosure.

[0030] Figure 6 A flow chart showing a method for manufacturing an inline rotor according to an embodiment of the present disclosure is shown, and

[0031] Figure 7 A flow chart of a method for manufacturing an inline rotor according to another embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the technical solution of the present disclosure clearer, the technical solution of the embodiment of the present disclosure will be clearly and completely described below in conjunction with the drawings of the specific embodiments of the present disclosure. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0033] Compared to the embodiments shown in the drawings, feasible embodiments within the scope of protection of the present disclosure may have fewer components, additional components not shown in the drawings, different components, differently arranged components, or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0034] Figure 1 A perspective view of an embedded rotor 100 according to an embodiment of the present disclosure is schematically shown. The embedded rotor 100 includes a first permanent magnet 110 and a second permanent magnet 120. The first permanent magnet 110 is configured as a cylinder and is integrally formed. In the present disclosure, the first permanent magnet 110 being configured as a cylinder is particularly understood to mean that the outer contour of the first permanent magnet 110 is a cylinder. In embodiments of the present disclosure, the outer circumferential surface of the first permanent magnet 110 can be, for example, a closed surface to provide greater structural strength. Figure 2 The exploded perspective view of the inline rotor 100 according to the embodiment of the present disclosure is schematically shown. Figure 2 As can be clearly seen in the figure, a plurality of spacing slots 130 are arranged circumferentially within the first permanent magnet 110, dividing the first permanent magnet into a plurality of first permanent magnet sub-segments by the spacing slots. In an embodiment according to the present disclosure, the spacing slots 130 penetrate the first permanent magnet 110 in the longitudinal direction, i.e., in the axial direction of the first permanent magnet 110. The plurality of second permanent magnets 120 are respectively arranged in the spacing slots 130, and in particular, are inserted into the spacing slots 130.

[0035] During the manufacturing process of the first permanent magnet, the space occupied by the spacing groove is used to place an orientation tool to apply a magnetic field, so that the first permanent magnet sub-portions on both sides of the spacing groove can obtain a deeper orientation depth, in preparation for the subsequent deeper magnetization depth.

[0036] In the prior art, permanent magnets in rotors are typically made of high-energy-product materials, such as neodymium iron boron. High-energy-product materials are expensive and have limited magnetization depth. Permanent magnets made of high-energy-product materials are typically placed on a magnetizer in an embedded or surface-mounted manner. Permanent magnets made of high-energy-product materials and rotors having such permanent magnets are typically small in size. In this case, it is necessary to enlarge the stator or increase the stator coils to increase the power of the synchronous motor. In contrast, in the present disclosure, the first permanent magnet can be made of a low-energy-product material, such as plastic magnets. Plastic magnet materials are relatively inexpensive. Deep orientation and magnetization of the first permanent magnet can be achieved through spacing slots in the first permanent magnet. Based on these two points, the first permanent magnet can be constructed as large as possible, and a rotor having such a first permanent magnet can provide a stronger magnetic field and more magnetic flux. The rotor according to the present disclosure can achieve the performance of a rotor made of high-energy-product materials.

[0037] In the prior art, the rotor of a permanent magnet synchronous motor consists of a magnetizer and permanent magnets. The permanent magnets can be attached to the magnetizer's surface to form a surface-mounted rotor, or inserted into the magnetizer to form an embedded rotor. These magnetizers are formed by stamping and stacking silicon steel sheets, making them difficult to manufacture using an integrated molding process.

[0038] Compared with the prior art, a first permanent magnet is used in place of a magnetizer in the rotor according to the present disclosure. The first permanent magnet according to the present disclosure is made of plastic magnetic material by injection molding and can be very conveniently prepared through an integrated molding process. Compared with the process of stamping and stacking silicon steel sheets, the integrated molding process of the first permanent magnet is simple in process, high in efficiency, high in precision, and low in cost. In addition, the first permanent magnet composed of plastic magnetic material can provide magnetic force itself, and its magnetic permeability is much higher than that of the silicon steel sheet magnetizer. Therefore, the rotor according to the present disclosure has a deeper magnetization depth, a higher material utilization rate, and a greater power density.

[0039] In this disclosure, one-piece molding is understood to mean the process of molding an entire part in a single mold. Compared to traditional, step-by-step manufacturing processes, one-piece molding significantly reduces production costs and accelerates production, enabling the production of a wide variety of parts, products, and tools in a fraction of the time.

[0040] The one-piece molding process is relatively simple and can complete the required contours, holes, surface treatments, etc. in one mold, which can greatly reduce production time and costs, while improving the production accuracy and repeatability of parts. In traditional processing methods, it is necessary to prepare the mold and template first, and then the parts are processed step by step. The one-piece molding process does not require additional preparation of templates and other requirements, and can truly be completed in one step, greatly improving processing efficiency and speed. In addition, the molds designed for the one-piece molding process are usually produced in one go, so the speed is very fast, and large-scale production can be completed quickly, which can meet market demand more quickly. The one-piece molding process can not only meet the needs of traditional manufacturing fields, but can also be applied to some high-tech fields, such as generators, car wash manufacturing, medical equipment, etc. In these fields, the one-piece molding process can create more precise and higher-quality parts and products.

[0041] The integrally molded first permanent magnet is made of a magnetic material, and preferably a magnetic material with low magnetic resistance and good magnetic permeability can be selected. In an embodiment according to the present disclosure, the first permanent magnet 110 can be made of, for example, plastic ferrite, for example, molded in one step by an injection molding method. Plastic ferrite has low magnetic resistance, good magnetic permeability, deep magnetization depth, and is suitable for integral molding and industrial production. In an embodiment according to the present disclosure, the plastic ferrite can be, for example, a mixture of nylon and ferrite. The first permanent magnet made of plastic ferrite accommodates the second permanent magnet, so the rotor space is fully utilized, so that the rotor can provide a larger magnetic flux without changing its volume. Plastic ferrite has a lower density than silicon steel material, which results in a reduced weight of the rotor made of plastic ferrite, thereby improving the power and energy efficiency of the motor. In addition, plastic ferrite has a higher resistivity than silicon steel material, so the rotor made of plastic ferrite can effectively reduce eddy current loss compared to the rotor made of silicon steel material.

[0042] Figure 3 FIG. 1 shows a schematic diagram of the magnetic field direction of the first permanent magnet 110 of the embedded rotor 100 according to an embodiment of the present disclosure. Figure 3 FIG. 1 shows a cross section of the embedded rotor 100 and its first permanent magnet 110. Figure 3As shown, the first permanent magnet sub-segments 111 and 112 on either side of a spacing slot 130 have opposite magnetic field directions along the radial direction of the first permanent magnet 110. For example, the magnetic field direction of the first permanent magnet sub-segment 111 is oriented outward along the radial direction of the first permanent magnet 110, while the magnetic field direction of the first permanent magnet sub-segment 112 is oriented inward along the radial direction of the first permanent magnet 110. The magnetic field direction of the first permanent magnet 110 and its respective first permanent magnet sub-segments is the magnetic field direction after magnetization or after the inserted second permanent magnet 120 is magnetized. It should be noted that the orientation direction of the first permanent magnet 110 during orientation is consistent with the magnetic field direction of the first permanent magnet 110 and its respective first permanent magnet sub-segments. When the first permanent magnet 110 and its respective first permanent magnet sub-segments are oriented, due to the externally applied aligning magnetic field, each first permanent magnet sub-segment of the first permanent magnet has improved magnetic conductivity, i.e., higher magnetic permeability and lower magnetic resistance, in a specific direction.

[0043] The second permanent magnet 120 is inserted into the spacing slot 130 to provide a magnetic field, and the magnetic field direction of the second permanent magnet 120 is designed so that the first permanent magnet sub-parts 111 and 112 on both sides of one of the spacing slots 130 and the second permanent magnet 120 form a continuous magnetic circuit with the shortest path. Figure 4 FIG. 1 is a schematic diagram showing the magnetic field directions of the second permanent magnets 121 and 122 of the embedded rotor 100 according to an embodiment of the present disclosure.

[0044] Figure 4 Two adjacent second permanent magnets 121 and 122 are shown as examples. The magnetic field directions of the second permanent magnets 121 and 122 are described below by taking the magnetic field directions of the second permanent magnets 121 and 122 as examples. The magnetic field directions of the other second permanent magnets can be known by comparison with the magnetic field directions of the second permanent magnets 121 and 122. In the embodiment according to the present disclosure, the magnetic field directions of the second permanent magnets 120, 121 and 122 can extend along the circumferential direction of the first permanent magnet 110, and from Figure 4 It can be seen that the magnetic field directions of the two adjacent second permanent magnets 121 and 122 are opposite. This magnetic field direction of the second permanent magnets 120, 121 and 122 enables the first permanent magnet sub-parts on both sides of an interval slot and the second permanent magnet in the interval slot to form a continuous magnetic circuit with the shortest path. Figure 5is more clearly shown in . In an embodiment according to the present disclosure, the material of the second permanent magnets 120, 121 and 122 may include, for example, ferrite, neodymium iron boron, samarium iron nitride and samarium cobalt. The second permanent magnet composed of samarium cobalt, neodymium iron boron or samarium iron nitride has strong remanence, high power density, large coercive force, and good anti-demagnetization ability, and is therefore very suitable for high-power, high-torque motors. In an embodiment according to the present disclosure, the second permanent magnets 120, 121 and 122 may be, for example, sintered or bonded, and may be, for example, sintered ferrite. In the case where the second permanent magnet is made of sintered ferrite, the entire rotor does not use rare earth materials at all, so the cost of the rotor is further reduced.

[0045] From the outside of the embedded rotor according to the present disclosure, the rotor has alternating N poles and S poles and forms a rotor with multiple pole pairs. Inside the embedded rotor according to the present disclosure, the first permanent magnet sub-portion corresponding to the S pole has a magnetic field direction extending radially inward, and the first permanent magnet sub-portion corresponding to the N pole has a magnetic field direction extending radially outward. Between adjacent S poles and N poles, the magnetic field starts from the S pole, transitions through the second permanent magnet along the shortest path and reaches the N pole, and the magnetic field in the second permanent magnet extends in the circumferential direction. Specifically, Figure 5 FIG. 1 shows a schematic diagram of the magnetic circuit of the embedded rotor 100 according to an embodiment of the present disclosure. Figure 5 As shown, the second permanent magnet 121 is arranged in the spacing slot 131, the second permanent magnet 122 is arranged in the spacing slot 132, and the second permanent magnet 123 is also shown, which is arranged in the spacing slot 133. The magnetic field direction of the second permanent magnet 123 extends along the circumferential direction of the first permanent magnet 110 and is opposite to the magnetic field direction of the adjacent second permanent magnet 122. On both sides of the second permanent magnet 122 or the spacing slot 132 are the first permanent magnet sub-sections 111 and 112, and on both sides of the second permanent magnet 123 or the spacing slot 133 are the first permanent magnet sub-sections 112 and 113. Figure 5As can be seen in the figure, the magnetic field originates from the south pole corresponding to the first permanent magnet subsection 112 and extends inward in the radial direction of the first permanent magnet 110 within the first permanent magnet subsection 112. The magnetic field then splits, with one portion bending through the second permanent magnet 122 and the other portion bending through the second permanent magnet 123. The magnetic field in the second permanent magnet 122 extends counterclockwise along the circumference of the first permanent magnet 110. After passing through the second permanent magnet 122, the magnetic field bends and extends outward in the radial direction of the first permanent magnet 110 through the first permanent magnet subsection 111, reaching the north pole corresponding to the first permanent magnet subsection 111. The magnetic field in the second permanent magnet 123 extends clockwise along the circumference of the first permanent magnet 110. After passing through the second permanent magnet 123, the magnetic field bends and extends outward in the radial direction of the first permanent magnet 110 through the first permanent magnet subsection 113, reaching the north pole corresponding to the first permanent magnet subsection 113. Based on the above description of the directions and orientations of the magnetic fields in the first permanent magnet sub-portions 111 , 112 and 113 and the second permanent magnets 122 and 123 , the directions and orientations of the magnetic fields in the other first permanent magnet sub-portions and second permanent magnets can be understood by comparison.

[0046] In the prior art, rotor magnets are typically formed by stamping and stacking silicon steel sheets. However, the magnetization depth of non-oriented silicon steel sheets is generally insufficient, while the magnetization direction of oriented silicon steel sheets is fixed, resulting in uneven magnetization depth after magnetization. Furthermore, manufacturing and assembling silicon steel sheets according to a desired orientation, such as that described in the embodiments of this disclosure, is inherently complex and costly.

[0047] Compared with the prior art, the embedded rotor according to the present invention adopts a first permanent magnet instead of a magnetizer. The first permanent magnet itself is magnetic and can provide additional magnetic flux. The rotor can therefore provide more magnetic flux, and a synchronous motor with such a rotor can obtain greater power and stronger performance. In the embedded rotor according to the present invention, a magnetic field application device, such as a strong magnetic device, can be arranged in the spacing slots in the first permanent magnet to orient and magnetize the first permanent magnet, so that the first permanent magnet obtains a desired magnetic field, for example, a deep orientation depth and magnetization depth in the radial direction of the first permanent magnet. In addition, the one-piece first permanent magnet is made of magnetic material, and preferably a magnetic material with low magnetic resistance and good magnetic permeability can be selected, and the processing technology of the one-piece first permanent magnet is simple, saves materials, is low in cost, and is very suitable for industrial mass production.

[0048] In the embodiment according to the present disclosure, the cross-section of the second permanent magnet 120 and the cross-section of the spacing slot 130 matched therewith can be configured into any shape, such as a triangle, a quadrilateral, other polygons, a circle, and the like.

[0049] In an embodiment of the present disclosure, the cross section of the second permanent magnet 120 may be configured as a trapezoid, for example. Figures 1 to 5 Furthermore, in the embodiment of the present disclosure, the lower base of the trapezoidal cross section is close to the center of the cross section of the first permanent magnet 110, while the upper base of the trapezoidal cross section is close to the circumference of the cross section of the first permanent magnet 110. The second permanent magnet 120 having a trapezoidal cross section can allow more of the magnetic field to pass through the first permanent magnet, thereby reducing magnetic flux leakage.

[0050] In an embodiment according to the present disclosure, Figure 1 and Figure 3 As shown in , a positioning portion 141 can be provided in the spacing groove 130, for example, and the positioning portion 141 is used to fix the second permanent magnet 120 in the spacing groove 130. In an embodiment according to the present disclosure, the positioning portion 141 is arranged in the spacing groove 130 on one side of the center of the cross section of the first permanent magnet 110 close to the first permanent magnet 110. In an embodiment according to the present disclosure, the positioning portion 141 is constructed as a protrusion for abutting against the second permanent magnet, and the protrusion can be constructed as a triangle or a semicircle, for example. The size of the spacing groove 130 of the first permanent magnet 110 is larger than that of the second permanent magnet 120, so that the second permanent magnet 120 can be inserted into the spacing groove 130 more easily. Therefore, a positioning portion 141 needs to be provided to fix the second permanent magnet 120 in the spacing groove 130.

[0051] In an embodiment according to the present disclosure, Figure 1 and Figure 3 As shown in FIG, an air slot 142 is provided between the second permanent magnet 120 disposed in the spacing slot 130 and the first permanent magnet 110 on the side facing the centerline of the first permanent magnet 110. The air slot 142 can be naturally formed, for example, by providing the positioning portion 141. That is, after the second permanent magnet 120 is inserted into the spacing slot 130, a gap is formed between the second permanent magnet 120 and the first permanent magnet 110 due to the large size of the spacing slot. Since air has a very low magnetic permeability, the air slot 142 can reduce magnetic flux leakage.

[0052] The present disclosure also provides a motor, comprising the above-mentioned embedded rotor according to the present disclosure. The motor may be, for example, a synchronous motor, a brushless DC motor, or the like.

[0053] The present disclosure also proposes a method for manufacturing an inline rotor. Figure 6 A flow chart of a method 600 for manufacturing an inline rotor according to an embodiment of the present disclosure is shown. Figure 6The method 600 for manufacturing an embedded rotor shown includes: manufacturing a first permanent magnet, wherein the first permanent magnet is configured as a cylinder and is integrally formed, and a plurality of spacing slots are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-segments by the spacing slots (step S610); arranging a first magnetic field applying device in the spacing slots, and orienting the first permanent magnet so that the first permanent magnet sub-segments on both sides of the spacing slots have opposite orientations along the radial direction of the first permanent magnet ( Step S620); manufacture a second permanent magnet (step S630); orient the second permanent magnet so that the orientation of the second permanent magnet extends along the circumferential direction of the first permanent magnet (step S640); arrange the second permanent magnet in the spacing slot (step S650); magnetize the first permanent magnet and the second permanent magnet according to the orientation of the first permanent magnet and the orientation of the second permanent magnet, so that the magnetic field of the second permanent magnet in the spacing slot and the magnetic field of the first permanent magnet on both sides of the spacing slot together form a continuous magnetic circuit with the shortest path. (Step S660). It should be noted that the orientation direction of the first permanent magnet and the second permanent magnet is the same as that of the first permanent magnet and the second permanent magnet. Figure 3 and Figure 5 The magnetic field directions of the first permanent magnets shown in FIG are consistent after magnetization, and when the first and second permanent magnets are magnetized, the magnetization directions are consistent with the orientations of the first and second permanent magnets. The magnetized embedded rotor forms the embedded rotor according to the embodiment of the present disclosure.

[0054] In the method for manufacturing an embedded rotor according to an embodiment of the present disclosure, since the first permanent magnet and the second permanent magnet have been pre-oriented, the first permanent magnet and the second permanent magnet have better magnetic permeability in the orientation direction. Therefore, when magnetization is subsequently performed, the magnetic circuit of the first permanent magnet and the second permanent magnet will generally and therefore have a better magnetization depth.

[0055] In an embodiment of the present disclosure, the first permanent magnet can be manufactured, for example, in an integral manner, using injection molding. The processing of the integrally molded first permanent magnet is simple and cost-effective. For example, the first permanent magnet can be manufactured in an integral manner using magnetic materials. Preferably, a magnetic material with low magnetic resistance and good magnetic permeability can be selected. In an embodiment of the present disclosure, the first permanent magnet can be manufactured, for example, using plastic magnets. Plastic magnets have low magnetic resistance, good magnetic permeability, and deep magnetization depth, making them suitable for integral molding and industrial production.

[0056] The present disclosure also proposes another method for manufacturing an inline rotor. Figure 7 A flow chart of a method 700 for manufacturing an inline rotor according to another embodiment of the present disclosure is shown. Figure 7The method 700 shown for manufacturing an embedded rotor includes: manufacturing a first permanent magnet, wherein the first permanent magnet is constructed as a cylinder and is integrally formed, and a plurality of spacing grooves are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves (step S710); arranging a first magnetic field application device in the spacing grooves, and orienting the first permanent magnet so that the first permanent magnet sub-portions on both sides of the spacing grooves have opposite orientations along the radial direction of the first permanent magnet (step S720); magnetizing the first permanent magnet according to the orientation of the first permanent magnet; (step S730); manufacturing a second permanent magnet (step S740); orienting the second permanent magnet so that the orientation of the second permanent magnet extends along the circumferential direction of the first permanent magnet (step S750); magnetizing the second permanent magnet according to the orientation of the second permanent magnet (step S760); and arranging the second permanent magnet in the spacing grooves (step S770). The magnetic field of the second permanent magnet in the spacing slot and the magnetic field of the first permanent magnet on both sides of the spacing slot together form a continuous magnetic circuit with the shortest path. Figure 3 and Figure 5 The magnetic field directions of the first permanent magnets shown in FIG are consistent after magnetization, and when the first and second permanent magnets are magnetized, the magnetization directions are consistent with the orientations of the first and second permanent magnets. The magnetized embedded rotor forms the embedded rotor according to the embodiment of the present disclosure.

[0057] In the method for manufacturing an embedded rotor according to an embodiment of the present disclosure, since the first permanent magnet and the second permanent magnet have been pre-oriented, the first permanent magnet and the second permanent magnet have better magnetic permeability in the orientation direction. Therefore, when magnetization is subsequently performed, the magnetic circuit of the first permanent magnet and the second permanent magnet will generally and therefore have a better magnetization depth.

[0058] In an embodiment of the present disclosure, the first permanent magnet can be manufactured, for example, in an integral manner, using injection molding. The processing of the integrally molded first permanent magnet is simple and cost-effective. For example, the first permanent magnet can be manufactured in an integral manner using magnetic materials. Preferably, a magnetic material with low magnetic resistance and good magnetic permeability can be selected. In an embodiment of the present disclosure, the first permanent magnet can be manufactured, for example, using plastic magnets. Plastic magnets have low magnetic resistance, good magnetic permeability, and deep magnetization depth, making them suitable for integral molding and industrial production.

[0059] In this document, unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by persons of ordinary skill in the field to which the present disclosure belongs. The words "first", "second" and similar terms used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not necessarily indicate a quantity limitation. Words such as "include" or "comprising" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0060] The exemplary implementation schemes proposed in the present disclosure are described in detail above with reference to preferred embodiments. However, it will be understood by those skilled in the art that, without departing from the concept of the present disclosure, various modifications and variations can be made to the above-mentioned specific embodiments, and various technical features and structures proposed in the present disclosure can be combined in various ways without exceeding the scope of protection of the present disclosure, which is determined by the appended claims.

Claims

1. An embedded rotor, comprising: a first permanent magnet, wherein the first permanent magnet is configured as a cylinder and is integrally formed, a plurality of spacing grooves are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; a second permanent magnet disposed in the spacing slot; The spacing groove is used to accommodate a magnetic field applying device during the orientation and magnetization process, so that the first permanent magnet obtains permanent magnetism; The first permanent magnet sub-portion has a magnetic field direction extending along the radial direction of the first permanent magnet, and the first permanent magnet sub-portions on both sides of the spacing slot have opposite magnetic field directions respectively; wherein the magnetic field direction of the second permanent magnet extends along the circumferential direction of the first permanent magnet; and The magnetic field of the second permanent magnet in the spacing slot and the magnetic field of the first permanent magnet on both sides of the spacing slot together form a continuous magnetic circuit with the shortest path.

2. The embedded rotor according to claim 1, wherein: The outer circumferential surface of the first permanent magnet is a closed surface.

3. The embedded rotor according to claim 1, wherein: The spacing groove penetrates the first permanent magnet along a longitudinal direction of the first permanent magnet.

4. The embedded rotor according to claim 1, wherein: The material of the first permanent magnet is plastic ferrite.

5. The embedded rotor according to claim 1, wherein: The second permanent magnet is sintered or bonded.

6. The embedded rotor according to claim 1, wherein: The second permanent magnet is made of one or more of ferrite, neodymium iron boron, samarium iron nitrogen and samarium cobalt.

7. The inline rotor according to claim 1, wherein: The cross section of the second permanent magnet is configured to be trapezoidal.

8. The inline rotor according to claim 7, wherein: The lower base of the trapezoidal cross section is close to the center of the cross section of the first permanent magnet.

9. The inline rotor according to claim 1, wherein: A positioning portion is provided in the spacing groove, and the positioning portion is used to fix the second permanent magnet in the spacing groove.

10. The inline rotor according to claim 9, wherein: The positioning portion is arranged in the spacing groove on one side close to the center of the cross section of the first permanent magnet.

11. The inline rotor according to claim 9 or 10, wherein: The positioning portion is configured as a protrusion for abutting against and fixing the second permanent magnet.

12. The inline rotor according to claim 1, wherein: An air slot is provided between the second permanent magnet disposed in the spacing slot and the first permanent magnet on a side facing the center line of the first permanent magnet.

13. An electric machine comprising the inline rotor according to any one of the preceding claims.

14. A method for manufacturing an inline rotor, comprising: Manufacturing a first permanent magnet, wherein the first permanent magnet is configured as a cylinder and is integrally formed, a plurality of spacing grooves are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; Arranging a first magnetic field applying device in the spacing slot and orienting the first permanent magnet so that the first permanent magnet sub-portions on both sides of the spacing slot have opposite orientations along the radial direction of the first permanent magnet; manufacturing a second permanent magnet; orienting the second permanent magnet so that the second permanent magnet extends along the circumferential direction of the first permanent magnet; placing the second permanent magnet in the spacing slot; The first permanent magnet and the second permanent magnet are magnetized according to the orientation of the first permanent magnet and the orientation of the second permanent magnet, so that the magnetic field of the second permanent magnet in the spacing slot and the magnetic fields of the first permanent magnets on both sides of the spacing slot together form a continuous magnetic circuit with the shortest path.

15. The method according to claim 14, wherein Manufacturing the first permanent magnet includes: manufacturing the first permanent magnet in an integral manner by injection molding.

16. A method for manufacturing an inline rotor, comprising: Manufacturing a first permanent magnet, wherein the first permanent magnet is configured as a cylinder and is integrally formed, a plurality of spacing grooves are arranged in a circumferential direction inside the first permanent magnet, and the first permanent magnet is divided into a plurality of first permanent magnet sub-portions by the spacing grooves; Arranging a first magnetic field applying device in the spacing slot and orienting the first permanent magnet so that the first permanent magnet sub-portions on both sides of the spacing slot have opposite orientations along the radial direction of the first permanent magnet; magnetizing the first permanent magnet according to the orientation of the first permanent magnet; manufacturing a second permanent magnet; orienting the second permanent magnet so that the second permanent magnet extends along the circumferential direction of the first permanent magnet; magnetizing the second permanent magnet according to the orientation of the second permanent magnet; placing the second permanent magnet in the spacing slot; The magnetic field of the second permanent magnet in the spacing slot and the magnetic field of the first permanent magnet on both sides of the spacing slot together form a continuous magnetic circuit with the shortest path.

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