Rotor

Abstract

A rotor comprises a central shaft and a plastic and magnetic powder mixing body. The central shaft has an axial direction. The plastic and the magnetic powder are arranged around the central shaft in a mixed mode and are an integrally-formed single component. The plastic and magnetic powder mixture comprises a first surface perpendicular to the axial direction, a second surface perpendicular to the axial direction, a plurality of ribs and a plurality of through holes. The second surface and the first surface face opposite directions. The ribs are arranged on the first face and / or the second face in a protruding mode and symmetrically arranged around the axial direction. The plurality of through holes penetrate between the first surface and the second surface and are arranged around the axial direction.

Description

Technical Field

[0001] This case relates to a rotor, and more particularly to a rotor made of a mixture of plastic and magnetic powder that has good heat dissipation properties. Background Technology

[0002] Generally speaking, rotors used in motors, such as internal rotors, are formed on a central shaft by combining magnets with plastic. The magnets need to be positioned in advance before the plastic is used to bond the magnets to the central shaft. The steps are relatively complicated and the process is somewhat complex.

[0003] In addition, during motor operation, heat is generated by the rotor itself or other components inside the motor, such as circuit components, silicon steel sheets, and copper wires. Improving heat dissipation and thus improving motor performance has long been an important issue in this field.

[0004] Therefore, it is necessary to develop a rotor that can improve upon the aforementioned deficiencies.

[0005] new content

[0006] The purpose of this invention is to provide a rotor with a simplified manufacturing process and improved heat dissipation.

[0007] To achieve the above objectives, this invention provides a rotor comprising a central shaft and a plastic-magnetic powder hybrid body. The central shaft has an axial direction. The plastic-magnetic powder hybrid body is arranged around the central shaft and is a single integrally formed component. The plastic-magnetic powder hybrid body includes a first surface perpendicular to the axial direction, a second surface perpendicular to the axial direction, a plurality of ribs, and a plurality of through holes. The second surface faces the opposite direction to the first surface. The plurality of ribs protrude from the first surface and / or the second surface and are symmetrically arranged around the axial direction. The plurality of through holes penetrate between the first surface and the second surface and are arranged around the axial direction.

[0008] In one embodiment, the plurality of ribs are arranged in a radial direction along the axial direction.

[0009] In one embodiment, the plurality of ribs includes a first portion of ribs and a second portion of ribs, the first portion of ribs protruding from a first surface and the second portion of ribs protruding from a second surface.

[0010] In one embodiment, the projection of the first portion of the rib onto a plane perpendicular to the axial direction at least partially overlaps with the projection of the second portion of the rib onto the same plane.

[0011] In one embodiment, the projection of the first portion of the rib onto a plane perpendicular to the axial direction and the projection of the second portion of the rib onto the same plane do not overlap.

[0012] In one embodiment, the plastic and magnetic powder mixed body further includes a third surface, which connects the outer edges of the first surface and the second surface respectively and is parallel to the axial direction.

[0013] In one embodiment, the maximum distance between each of the plurality of ribs and the axial direction is less than or equal to the distance between the third surface and the axial direction.

[0014] In one embodiment, the distance between the longitudinal axis and the axial direction of each of the plurality of through holes is less than the distance between the hole and the third surface.

[0015] In one embodiment, the plastic and magnetic powder mixing body further includes at least one groove surrounding the central axis and formed on the plastic and magnetic powder mixing body in a direction from the first surface to the second surface and / or formed on the plastic and magnetic powder mixing body in a direction from the second surface to the first surface.

[0016] In one embodiment, the distance between the inner edge of at least one groove and the periphery of the central axis is greater than zero.

[0017] In one embodiment, a plurality of through holes correspond axially to at least one groove.

[0018] In one embodiment, the first surface includes a first inner ring surface and a first outer ring surface, and at least one groove is located between the first inner ring surface and the first outer ring surface, and / or the second surface includes a second inner ring surface and a second outer ring surface, and at least one groove is located between the second inner ring surface and the second outer ring surface.

[0019] In one embodiment, a plurality of ribs protrude from the first outer ring surface and / or the second outer ring surface.

[0020] In one embodiment, at least one of the plurality of through holes is disposed between two adjacent ribs among the plurality of ribs.

[0021] In one embodiment, each of the plurality of ribs has different polarities on both sides.

[0022] The rotor in this case is made of a mixture of plastic and magnetic powder, which greatly simplifies the process to a single injection molding step, effectively reducing process complexity. Furthermore, the ribs protruding from the surface of the body can create air turbulence during operation, and the through holes that penetrate the interior can generate circulating airflow through the body during operation. Both of these contribute to improving heat dissipation and thus improving performance. Attached Figure Description

[0023] Figure 1A This diagram shows a rotor according to an embodiment of the present invention.

[0024] Figure 1B This shows a schematic diagram of the rotor from another angle according to an embodiment of the present case.

[0025] Figure 2A This shows a side view of the rotor according to an embodiment of the present case.

[0026] Figure 2B Showing a top view of the rotor according to an embodiment of this case.

[0027] Figure 2C Showing a bottom view of the rotor according to an embodiment of this case.

[0028] Figure 3 A schematic diagram showing the central shaft of the rotor according to an embodiment of this case is displayed.

[0029] Figure 4A show Figure 2B A sectional view of the A-A' plane.

[0030] Figure 4B show Figure 2B A sectional view of the B-B' plane.

[0031] Figure 5A Showing a top view of the rotor of another embodiment of this case.

[0032] Figure 5B Showing a bottom view of the rotor of another embodiment of this case.

[0033] Figure 6 This diagram shows a rotor according to another embodiment of the present invention.

[0034] Figures 7A to 7D This section shows different examples of the ribs on the rotor in this case.

[0035] Figures 8A to 8B This section shows different examples of the magnetic pole configurations of the rotor in this case.

[0036] The annotations in the attached figures are explained as follows:

[0037] 1: Rotor 10: Central Shaft

[0038] 11: Undulating section 20: Main body

[0039] 21: First face 211: First inner ring face

[0040] 212: First outer torus 22: Second torus

[0041] 221: Second inner torus 222: Second outer torus

[0042] 23: Third page

[0043] 24, 24', 24”, 24a, 24b, 24c, 24d: Ribs

[0044] 241', 241”, 241a, 241b, 241c, 241d: Top surface

[0045] 242', 242", 242a, 242b: Connecting surfaces

[0046] 25: Through hole; 26', 26”: Groove

[0047] 27: Connecting part A-A': Section

[0048] B-B': Section C: Axial

[0049] D1, D2: Distance E: Airflow

[0050] L1, L2: Distances; N, S: Magnetic poles Detailed Implementation

[0051] Some typical embodiments that embody the features and advantages of this invention will be described in detail in the following description. It should be understood that this invention can have various variations in different forms, but none of them depart from the scope of this invention, and the descriptions and illustrations therein are for illustrative purposes only and not intended to limit this invention.

[0052] Please see Figures 1A to 1B , Figures 2A to 2C , Figure 3 ,and Figures 4A to 4B . Figure 1A A schematic diagram of the rotor according to an embodiment of this case is shown. Figure 1B This diagram shows another angle view of the rotor according to an embodiment of the present invention. Figures 2A to 2C The side view, top view, and bottom view of the rotor according to the embodiment of this case are shown respectively. Figure 3 A schematic diagram of the central shaft of the rotor according to an embodiment of this case is shown. Figure 4A show Figure 2B A sectional view of the A-A' plane, and Figure 4B show Figure 2B A cross-sectional view along plane B-B'. The rotor 1 of this invention is suitable for a motor, such as an internal rotor motor, and is matched with the stator within the motor to achieve motor operation. The rotor 1 includes a central shaft 10 and a body 20. The central shaft 10 has an axial direction C, and the body 20 is disposed around the central shaft 10. In this invention, particularly, the body 20 is a single, integrally molded component made of a mixture of plastic and magnetic powder; that is, the rotor 1 of this invention comprises only two components: the central shaft 10 and the body 20.

[0053] Compared to existing technologies where the rotor is manufactured by first positioning the magnet and then using plastic to place the magnet around the central shaft, the rotor body 20 in this invention uses a material that combines plastic and magnetic powder. Therefore, it can simultaneously provide both magnetic force and adhesion. Consequently, a single injection molding process can be used to simultaneously attach the body 20 to the central shaft 10 and place the magnetic material around the central shaft 10, significantly simplifying the process. Furthermore, since the step of first positioning the magnet in existing technologies is omitted, the molding and positioning of the body 20 can be completed using a single mold. Therefore, the positioning of each component on the body 20 and the central shaft 10 can be more precise. In addition, as... Figure 3 and Figure 4A As shown, the central shaft 10 has undulating sections 11 at the position corresponding to the body 20, such as sections with steps, knurling, etc., which helps to increase the bonding force between the body 20 and the central shaft 10.

[0054] The body 20 is generally formed as an annular body surrounding the central axis 10. The body 20 includes a central channel, a first surface 21, a second surface 22, a third surface 23, a plurality of ribs 24, and a plurality of through holes 25. The central channel is used to accommodate the central axis 10. The first surface 21 and the second surface 22 are parallel to each other and perpendicular to the axial direction C; in other words, the first surface 21 and the second surface 22 are two planes facing opposite directions. Figure 2A As shown, the first surface 21 faces upward and the second surface 22 faces downward. The third surface 23 connects the outer edges of the first surface 21 and the second surface 22 and is parallel to the axial direction C. Therefore, the third surface 23 is a curved surface surrounding the central axis 10, and the first surface 21, the second surface 22, and the third surface 23 together enclose the main part of the body 20. Secondly, a plurality of ribs 24 are provided on the first surface 21 and / or the second surface 22, symmetrically arranged around the axial direction C, and protrude in a direction away from the first surface 21 and the second surface 22. Furthermore, a plurality of through holes 25 are provided inside the body 20, penetrating between the first surface 21 and the second surface 22. Therefore, the plurality of through holes 25 will correspondingly form a plurality of holes on the first surface 21 and the second surface 22. Additionally, the plurality of through holes 25 are arranged in a manner parallel to and around the axial direction C, for example, symmetrically.

[0055] On the one hand, since the plurality of ribs 24 are protruding from the first surface 21 and / or the second surface 22, when the rotor 1 rotates around the axial direction C, the structural undulations formed by the ribs 24 can cause turbulent airflow around the rotor 1, thereby achieving a heat dissipation effect. This is especially helpful for dissipating heat from components around the rotor 1, such as circuit components, silicon steel sheets, and copper wires. On the other hand, since the plurality of through holes 25 are channels penetrating between the first surface 21 and the second surface 22, that is, air can flow through them, when the rotor 1 rotates, as... Figure 4BAs shown, an airflow E that continuously circulates within each through-hole 25 can be generated, which also helps to improve the heat dissipation effect. More specifically, in this case, through the cooperation of the ribs 24 and the through-holes 25, not only is a turbulent airflow generated around the rotor 1 to help dissipate heat from the surrounding components, but an airflow is also generated inside the rotor 1 to further assist in heat dissipation, thereby significantly improving both the heat dissipation effect and the operating performance.

[0056] Furthermore, since the rotor 1 is manufactured in a single piece using an injection molding process, the protruding ribs 24 can be further used to perform balancing operations, facilitating balance adjustments after the rotor 1 is formed. Additionally, the arrangement of the plurality of through holes 25 within the body 20 is preferably close to the central axis 10; that is, the distance L1 between the longitudinal axis of the through hole 25 and the central axis 10 is less than the distance L2 between the longitudinal axis of the through hole 25 and the third surface 23. For example, in one embodiment, the distance L1 is less than half the distance L2, ensuring that the volume of the body 20 located on the other side of the through hole 25 relative to the central axis 10 is sufficient to provide the magnetic properties required for motor operation. Furthermore, when arranging the through holes 25, the mechanical connection strength provided by the connecting portions 27 between adjacent through holes 25 must be sufficient to maintain motor operation. More specifically, the number, cross-sectional area, and distribution of the through holes 25 and connecting portions 27 can be varied, provided that a balance can be achieved between actual heat dissipation requirements and required mechanical strength. In addition, the through-hole 25 also helps to save materials and thus reduce costs.

[0057] The body 20 may further include at least one groove 26 recessed into the body 20 from the first surface 21 and / or the second surface 22. This design not only helps to save materials and reduce costs, but also creates air turbulence along with the ribs 24 by forming an undulating structure on the first surface 21 and / or the second surface 22, thereby aiding in heat dissipation. The at least one groove 26 is configured to surround the central axis 10, with the distance between its inner edge and the periphery of the central axis 10 greater than zero. This design maximizes the mating surface between the body 20 and the central axis 10, helping to maintain the bonding force between the body 20 and the central axis 10 while saving materials. In one embodiment, the at least one groove 26 includes a groove 26' and a groove 26"', wherein groove 26' is formed in the body 20 from the first surface 21 toward the second surface 22, and groove 26"' is formed in the body 20 from the second surface 22 toward the first surface 21. The groove 26' separates the first surface 21 into a first inner ring surface 211 and a first outer ring surface 212, and the groove 26" separates the second surface 22 into a second inner ring surface 221 and a second outer ring surface 222. In this embodiment, the positions of the grooves 26' and 26" correspond exactly to the positions of the plurality of through holes 25. That is, the plurality of through holes 25 correspond to the grooves 26' and 26" along the axial direction C, and the plurality of through holes 25 fall between the first inner ring surface 211 and the first outer ring surface 212 and / or between the second inner ring surface 221 and the second outer ring surface 222. In other embodiments, the positions of the grooves 26' and 26" may also be staggered or partially overlapped with the positions of the plurality of through holes 25, and can be varied according to actual needs. On the other hand, in other embodiments, the body 20 may also be implemented without grooves, or with groove 26' only on the first surface 21, or with groove 26" only on the second surface 22. When no grooves are provided, such as Figures 5A to 5B As shown, the first surface 21 and the second surface 22 are single annular surfaces extending from the periphery of the central axis 10 to the third surface 23, and a plurality of through holes 25 are correspondingly formed in the first surface 21 and the second surface 22. Therefore, whether to provide grooves and to change the location of grooves can be selected according to actual implementation needs, and this invention is not limited thereto.

[0058] In this case, the ribs 24 are positioned on the first surface 21 and / or the second surface 22, but not exceeding the space enclosed by the downward extension of the third surface 23. That is, the maximum distance D1 between each rib 24 and the axial direction C (i.e., the distance between the far end of each rib 24 relative to the central axis 10 and the axial direction C) is less than or equal to the distance D2 between the third surface 23 of the body 20 and the axial direction C. Within this range, provided the overall balance of the rotor 1 is maintained, the ribs 24 can be implemented in various forms and arrangements according to actual needs, without limitation. Furthermore, when the groove 26 is provided, the position of the ribs 24 can also be adjusted accordingly. For example, they can be positioned on the first inner ring surface 211 / second inner ring surface 221 of the first surface 21 and / or the second surface 22, the first outer ring surface 212 / second outer ring surface 222, or both, all depending on actual needs.

[0059] Depending on their placement, the plurality of ribs 24 can be further divided into a first portion rib 24' protruding from the first surface 21 and a second portion rib 24' protruding from the second surface 22. The first portion rib 24' is arranged symmetrically around the axis C on the first surface 21, and the second portion rib 24' is also arranged symmetrically around the axis C on the second surface 22. The first portion rib 24' extends away from the first surface 21, and the second portion rib 24' extends away from the second surface 22; that is, the first portion rib 24' and the second portion rib 24' extend in opposite directions. Figure 2A As shown, the first rib 24' extends upward from the first surface 21, and the second rib 24" extends downward from the second surface 22. In other embodiments, the first rib 24' and the second rib 24" may be optionally provided, for example, as shown in the figure. Figure 6 The first part of the rib 24' shown is provided only on the first surface 21, or the second part of the rib 24' is provided only on the second surface 22, both of which fall within the scope of this case.

[0060] Furthermore, when both the first rib 24' and the second rib 24" are provided, their respective arrangements can be the same or different. That is, the projections of the first rib 24' and the second rib 24" onto the plane perpendicular to the axial direction C can overlap, partially overlap, or not overlap. This can be arbitrarily varied provided that the rotor 1 as a whole can maintain balance.

[0061] Furthermore, the positional relationship between the plurality of ribs 24 and the plurality of through holes 25 can be implemented in various ways. For example, in one embodiment, such as Figure 2B , Figure 2C , Figure 5A and Figure 5BAs shown, the position of the through hole 25 is implemented to correspond to the space between two adjacent ribs 24' and two adjacent ribs 24"; in another embodiment, the position of the through hole 25 may also be implemented to correspond to ribs 24' and / or ribs 24"; in another embodiment, depending on the different positions of the ribs 24' and 24", the positions of different through holes 25 may be respectively implemented to correspond to the space between adjacent ribs, to correspond to one of the ribs, or not specifically to the position of the ribs. In addition, since the positions of the ribs 24' on the first surface 21 and the ribs 24" on the second surface 22 may be implemented differently, the positional relationship between the through hole 25 and the rib 24' on the first surface 21 may also be different from the positional relationship between the through hole 25 and the rib 24" on the second surface 22.

[0062] Each of the plurality of ribs 24 can be implemented in various different forms. For example, in one embodiment, such as Figures 1A to 1B As shown, the ribs 24' and 24" are implemented as three-dimensional rectangular structures symmetrically arranged radially along the central axis 10. The top surfaces 241' and 241" are generally parallel to the first outer ring surface 212 / second outer ring surface 222, and are connected to the first outer ring surface 212 / second outer ring surface 222 by arc-shaped connecting surfaces 242' and 242" respectively. The ribs 24' and 24" extend approximately from the inner edge to the outer edge of the first outer ring surface 212 / second outer ring surface 222. In another embodiment, as... Figure 7A As shown, the rib 24a is implemented as a three-dimensional rectangular structure symmetrically arranged radially along the central axis 10. The top surface 241a is approximately parallel to the first outer ring surface 212, and an arc-shaped connecting surface 242a is formed between the rib 24a and the first outer ring surface 212. There are gaps between the inner and outer edges of the rib 24a and the first outer ring surface 212. In another embodiment, as... Figure 7B As shown, the rib 24b is implemented as a three-dimensional curved surface structure symmetrically arranged in the radial direction along the central axis 10. Its height relative to the first outer ring surface 212 gradually increases in a curved manner from the inner edge to the outer edge of the first outer ring surface 212. That is, the top surface 241b is not parallel to the first outer ring surface 212, and an arc-shaped connecting surface 242b is implemented between them. In another embodiment, as... Figure 7C As shown, the rib 24c is implemented as a quarter-cylindrical structure symmetrically arranged radially along the central axis 10, with its top surface 241c substantially parallel to the first outer annular surface 212, and the rib 24c extending substantially from the inner edge to the outer edge of the first outer annular surface 212; alternatively, the rib 24c may also be implemented as a semi-cylindrical shape, or other shapes cut along the long axis of a cylinder. In another embodiment, such as Figure 7D As shown, the rib 24d is implemented as a plurality of three-dimensional rectangular structures arranged symmetrically in the radial direction along the central axis 10. That is, each radial direction has a plurality of spaced sub-ribs, and the length of each sub-rib in the radial direction may be the same or different from each other. The top surface 241d is approximately parallel to the first outer ring surface 212.

[0063] Therefore, the arrangement of ribs 24, 24a, 24b, 24c, and 24d on the first surface 21 / second surface 22 can be implemented in various ways, and their shape, size, and / or placement are not specifically limited. For example, the top surface of each rib may be parallel or non-parallel to the first surface 21 / second surface 22, and / or each rib may be a single component or composed of multiple components. Furthermore, the ribs arranged on the first surface 21 or on the second surface 22 may be the same or different from each other. For example, the first surface 21 may simultaneously employ... Figure 1A As shown and as Figure 7A The different ribs shown. Any structure that protrudes from the first surface 21 and / or the second surface 22 and can cause disturbance to the surrounding air during the rotation of the rotor 1 falls within the scope of this application and can be varied according to actual usage requirements.

[0064] It should be noted that although the ribs 24, 24a, 24b, 24c, and 24d in the above diagram are drawn in the radial direction along the axial direction C, the position and direction of each rib 24 can be changed under the premise that the rotor 1 can achieve balance, and the scope of this case is not limited to this.

[0065] In this case, since the body 20 is a single component made from a single material, namely a mixture of plastic and magnetic powder, using an injection molding process, the entire body 20, including the ribs 24, connecting parts 27, and all other components, is made of the same material and therefore possesses magnetism. Furthermore, after the body 20 is formed, the rotor 1 can be manufactured simply by using a magnetizer to set the magnetism. The number of magnetic poles N and S is not limited and can be arranged as follows: Figure 8A As shown, two N-pole and two S-pole are set, or as follows: Figure 8B As shown, four N poles and four S poles are set, which can be varied according to actual needs. In one embodiment, the polarity of the body 20 can be further set such that each rib 24 has different polarities on both sides, for example, in... Figure 8B In the illustrated embodiment, the position of each magnetic pole is set to fall between adjacent ribs 24; or as shown in the example Figure 8A In the embodiment shown, which only has two N poles and two S poles, the polarities on both sides of each rib 24 are also different from each other.

[0066] In summary, the rotor of this invention uses a mixture of plastic and magnetic powder as the material, thus enabling the injection molding process to directly form the body around the central shaft in a single step, thereby completing the rotor's fabrication and significantly reducing manufacturing complexity. Furthermore, the rotor of this invention is further provided with ribs on the surface of the body and through holes inside the body, which can cause disturbance of the surrounding air and generate circulating airflow inside the rotor during rotor operation, effectively improving heat dissipation.

[0067] It should be noted that the above are merely preferred embodiments for illustrating this case, and this case is not limited to the described embodiments. The scope of this case is determined by the appended claims. Furthermore, this case can be modified in various ways by those skilled in the art, but all such modifications will not depart from the protection sought by the appended claims.

Claims

1. A rotor, suitable for a motor, comprising: A central axis, having an axial direction; and A plastic and magnetic powder hybrid body is disposed around the central axis and is a single integrally molded component. The plastic and magnetic powder hybrid body comprises: The first surface is perpendicular to this axis; A second surface, perpendicular to the axial direction, and the second surface faces the opposite direction to the first surface; A plurality of ribs protrude from the first surface and / or the second surface and are symmetrically arranged around the axial direction; and A plurality of through holes are provided, passing through the first surface and the second surface, and arranged around the axial direction.

2. The rotor as claimed in claim 1, wherein the plurality of ribs are arranged in a radial direction along the axial direction.

3. The rotor as claimed in claim 1, wherein the plurality of ribs includes a first portion rib and a second portion rib, the first portion rib protruding from the first surface and the second portion rib protruding from the second surface.

4. The rotor of claim 3, wherein the projection of the first portion of the rib onto a plane perpendicular to the axial direction at least partially overlaps the projection of the second portion of the rib onto the same plane.

5. The rotor of claim 3, wherein the projection of the first portion of the rib onto a plane perpendicular to the axial direction and the projection of the second portion of the rib onto the same plane do not overlap.

6. The rotor as claimed in claim 1, wherein the plastic and magnetic powder mixed body further includes a third surface, which connects the outer edges of the first surface and the second surface respectively and is parallel to the axial direction.

7. The rotor of claim 6, wherein the maximum distance between each of the plurality of ribs and the axial direction is less than or equal to the distance between the third surface and the axial direction.

8. The rotor of claim 6, wherein the distance between the longitudinal axis of each of the plurality of through holes and the axial direction is less than the distance between the longitudinal axis and the axial direction.

9. The rotor of claim 1, wherein the plastic and magnetic powder mixed body further includes at least one groove surrounding the central shaft and formed on the plastic and magnetic powder mixed body in a direction from the first surface toward the second surface and / or formed on the plastic and magnetic powder mixed body in a direction from the second surface toward the first surface.

10. The rotor of claim 9, wherein the distance between the inner edge of the at least one groove and the periphery of the central shaft is greater than zero.

11. The rotor of claim 9, wherein the plurality of through holes corresponds axially to at least one groove.

12. The rotor of claim 9, wherein the first surface comprises a first inner annular surface and a first outer annular surface, and the at least one groove is located between the first inner annular surface and the first outer annular surface, and / or the second surface comprises a second inner annular surface and a second outer annular surface, and the at least one groove is located between the second inner annular surface and the second outer annular surface.

13. The rotor as claimed in claim 12, wherein the plurality of ribs protrude from the first outer ring surface and / or the second outer ring surface.

14. The rotor of claim 1, wherein at least one of the plurality of through holes is disposed between two adjacent ribs of the plurality of ribs.

15. The rotor of claim 1, wherein each of the plurality of ribs has different polarities on both sides.

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