Magnet structure, motor, electric power steering system and vehicle

Abstract

The utility model provides a magnet structure, a motor, an electric power steering system and a vehicle, the magnet structure is used for the motor, and the magnet structure comprises an injection molding magnet; the shaft part is provided with an injection molding hole and a discharging hole, the two ends of the discharging hole penetrate through the side wall of the shaft part, one end of the injection molding hole penetrates through the first end of the shaft part, the other end of the injection molding hole is communicated with the discharging hole, one part of the injection molding magnet is arranged on the side wall of the shaft part in a surrounding mode, and the other part of the injection molding magnet is embedded into at least one part of the injection molding hole and the discharging hole. A sprue part is arranged at the part, positioned in the injection molding hole, of the injection molding magnet. According to the magnet structure provided by the utility model, all parts of the injection molding magnet in the circumferential direction of the shaft part are more symmetrical, so that the influence of the shape of the sprue part on the symmetry of the magnetic field of the injection molding magnet is avoided, the symmetry of the magnetic field of the injection molding magnet is improved, and the precision of rotation angle detection is further improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to electric power assist technical field, specifically, relate to a magnet structure, motor, electric power assist steering system and vehicle. BACKGROUND

[0002] At present, in electric power assist steering system, injection molding magnet is in the chip of motor controller, bears the function of detecting motor angle. In the related art, the gate formed when injection molding magnet is injection molding belongs to recess or convex, this can make injection molding magnet asymmetric, thereby causing the influence to the symmetry of magnetic field, further can influence the detection precision of motor rotation angle. SUMMARY

[0003] The utility model aims at at least one of the technical problems in prior art or related art.

[0004] Therefore, the first aspect of the utility model provides a magnet structure.

[0005] The second aspect of the utility model further provides a motor.

[0006] The third aspect of the utility model further provides an electric power assist steering system.

[0007] The fourth aspect of the utility model further provides a vehicle.

[0008] Therefore, the first aspect of the utility model provides a magnet structure, the magnet structure is used for motor, and the magnet structure includes: injection molding magnet, shaft part, the shaft part is equipped with injection molding hole and discharge hole, the both ends of discharge hole are through the side wall of the shaft part, the one end of injection molding hole is through the first end of the shaft part, and the other end of injection molding hole is communicated with discharge hole, wherein a part of injection molding magnet is surrounded in the side wall of the shaft part, another part of injection molding magnet is embedded in at least a part of injection molding hole and discharge hole, and the part of injection molding magnet in injection molding hole is provided with gate part.

[0009] The magnet structure provided by the utility model is used for motor, and the magnet structure includes injection molding magnet and shaft part, the shaft part is provided with injection molding hole and discharge hole, the one end of injection molding hole is through the first end of the shaft part, and the other end of injection molding hole is communicated with discharge hole, so that when injection molding magnet structure is formed, the material used for manufacturing injection molding magnet is injected from injection molding hole, and the material flows to the mold from discharge hole to injection mold injection molding magnet, so that a part of injection molding magnet is surrounded in the side wall of the shaft part, and another part is embedded in at least a part of injection molding hole and discharge hole, simultaneously, the gate part caused by injection molding is formed in injection molding hole, that is, the gate part is located in the middle of injection molding magnet, so that each part of injection molding magnet is more symmetrical in the circumference of the shaft part, thereby avoiding that the shape of gate part influences the symmetry of the magnetic field of injection molding magnet, improving the symmetry of the magnetic field of injection molding magnet, and further improving the precision of rotation angle detection.

[0010] According to the magnet structure provided by the utility model, the following additional technical features can be further provided:

[0011] In some embodiments, optionally, the side of the gate portion facing the first end is located in the injection hole.

[0012] In this embodiment, the side of the gate portion facing the first end is located in the injection hole, so that the gate portion does not protrude out of the injection hole, and thus the part of the injection molded magnet located in the injection hole does not protrude out of the injection hole, ensuring the reliability of the injection molding, avoiding the injection material flowing to other positions and affecting the symmetry of the injection molded magnet. In addition, when the magnet structure is press-fitted in the shaft hole of the rotating shaft of the motor, the injection molded magnet can be avoided from being pressed down, and thus the situation of the injection molded magnet being broken can be avoided.

[0013] In some embodiments, optionally, the gate portion comprises: a first recess, the first recess being recessed from the injection molded magnet to the second end of the shaft portion; and a second recess, the second recess being located in the first recess and recessed to the second end, and the cross-sectional area of the second recess being smaller than that of the first recess.

[0014] In this embodiment, the gate portion comprises the first recess and the second recess, the second recess is arranged in the first recess and recessed to the second end, and the cross-sectional area of the second recess is smaller than that of the first recess, so that the pressure loss is reduced during injection, and thus the material is uniformly filled in the mold, and the magnetic field uniformity of the injection molded magnet is improved.

[0015] In some embodiments, optionally, in the cross section of the injection hole and the cross section of the shaft portion, among the lines connecting any two points on the side wall of the shaft portion, the line passing through the center of the shaft portion is the first line, among the lines connecting any two points on the side wall of the injection hole, the line passing through the center of the shaft portion is the second line, and the ratio of the length of the second line to the length of the first line is greater than or equal to 1 / 4 and less than or equal to 2 / 3.

[0016] In this embodiment, if the size of the injection hole is too large, the strength of the shaft portion will be affected, and correspondingly, if the size of the injection hole is too small, the injection speed of the material will be affected, and the material is prone to be blocked, therefore, the ratio of the length of the second line to the length of the first line is limited to between 1 / 4 and 2 / 3, which can ensure the strength of the shaft portion and the reliability of the material injection.

[0017] In some embodiments, optionally, the axis of the injection hole coincides with the axis of the shaft portion; and / or the axis of the discharge hole coincides with the radial direction of the shaft portion.

[0018] In this embodiment, the axis of the injection hole coincides with the axis of the shaft portion, so that the injection hole is coaxially arranged with the shaft portion, so that the part of the injection-molded magnet formed in the injection hole is more symmetrical relative to the axis of the shaft portion, the symmetry of the injection-molded magnet is improved, and the detection accuracy of the motor rotation angle is improved. The axis of the discharge hole coincides with the radial direction of the shaft portion, that is, the discharge hole penetrates the shaft portion along the radial direction of the shaft portion, so that the part of the injection-molded magnet formed in the discharge hole is more symmetrical, and the symmetry of the injection-molded magnet as a whole is improved.

[0019] In some embodiments, optionally, the injection-molded magnet is symmetrically arranged along the radial direction of the shaft portion.

[0020] In this embodiment, the injection-molded magnet is symmetrically arranged along the radial direction of the shaft portion, the symmetry of the magnetic field of the injection-molded magnet is improved, and the detection accuracy of the motor is improved.

[0021] According to the second aspect of the utility model, a motor is further provided, which comprises: a detection member; and the magnet structure according to any one of the above embodiments, and the magnet structure can rotate relative to the detection member to enable the detection member to detect the angle information of the motor according to the magnet structure.

[0022] The motor provided by the second aspect of the utility model has all the beneficial effects of the magnet structure, and through the cooperation of the detection member and the magnet structure, the detection of the rotation angle of the motor is realized.

[0023] In some embodiments, optionally, the motor further comprises: a rotating shaft, the rotating shaft comprises a shaft hole, and the second end of the shaft portion of the magnet structure is arranged in the shaft hole; wherein in the cross section of the shaft portion and the cross section of the rotating shaft, among the lines connecting any two points on the side wall of the shaft portion, the line passing through the center of the shaft portion is a first line, among the lines connecting any two points on the side wall of the rotating shaft, the line passing through the center of the rotating shaft is a third line, and the ratio of the length of the first line to the length of the third line is greater than or equal to 1 / 4 and less than or equal to 1 / 2.

[0024] In this embodiment, the motor further comprises a rotating shaft, the second end of the shaft portion is installed in the shaft hole of the rotating shaft, the installation of the motor and the magnet structure is realized, so that in the process of rotating the motor, the magnet structure can rotate with the rotating shaft through the shaft portion, and the detection of the rotation angle of the motor can be realized. When the size difference between the shaft portion and the rotating shaft is large, the strength of the shaft portion is affected, and when the size difference between the shaft portion and the rotating shaft is small, the energy consumption of the electric power steering system is increased, therefore, the ratio of the length of the first line to the length of the third line is set to be between 1 / 4 and 1 / 2, which can ensure the strength of the shaft portion and reduce the energy consumption of the motor driving the shaft portion to rotate.

[0025] According to the third aspect of the utility model, an electric power steering system is further provided, comprising: the magnet structure according to any one of the above embodiments; or the motor according to the above embodiments.

[0026] The electric power steering system provided by the third aspect of the utility model has all the beneficial effects of the magnet structure or the motor.

[0027] According to the fourth aspect of the utility model, a vehicle is further provided, comprising: the magnet structure according to any one of the above embodiments; or the motor according to the above embodiments; or the electric power steering system according to the above embodiments.

[0028] The vehicle provided by the fourth aspect of the utility model has all the beneficial effects of the magnet structure or the motor or the electric power steering system.

[0029] The additional aspects and advantages of the utility model will become apparent from the following description part or be understood through the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0030] The above and / or additional aspects and advantages of the utility model will become apparent and easily understood from the description of embodiments in conjunction with the following drawings, in which:

[0031] Figure 1 Fig. 1 shows a structural schematic diagram of a magnet structure of one embodiment of the utility model;

[0032] Figure 2 Fig. 2 shows a structural schematic diagram of a magnet structure of another embodiment of the utility model;

[0033] Figure 3 Fig. 3 shows a structural schematic diagram of a magnet structure of another embodiment of the utility model;

[0034] Figure 4 Fig. 4 shows a structural schematic diagram of a shaft part of one embodiment of the utility model;

[0035] Figure 5 Fig. 5 shows a structural schematic diagram of a shaft part of another embodiment of the utility model;

[0036] Figure 6 Fig. 6 shows a structural schematic diagram of an electric power steering system of one embodiment of the utility model;

[0037] Figure 7 Fig. 7 shows a structural schematic diagram of an electric power steering system of another embodiment of the utility model.

[0038] wherein,Figures 1 to 7 Correspondence between reference signs and component names is as follows:

[0039] 1 magnet structure, 10 injection molded magnet, 100 gate portion, 102 first recess, 104 second recess, 12 shaft portion, 120 injection hole, 122 discharge hole, 124 first end, 126 second end, 2 motor, 20 rotating shaft, 202 shaft hole, 22 detection piece. DETAILED DESCRIPTION

[0040] In order to enable the above objects, features and advantages of the present application to be more clearly understood, the following will further describe the present application with reference to the drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0041] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, however, the present application can be practiced in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0042] The following will be described with reference to Figures 1 to 7 A magnet structure 1, a motor 2, an electric power steering system and a vehicle according to some embodiments of the present application are described.

[0043] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 , according to one embodiment of the present application, the present application proposes a magnet structure 1, the magnet structure 1 is used for a motor 2, the magnet structure 1 comprises: an injection molded magnet 10; a shaft portion 12, the shaft portion 12 is provided with an injection hole 120 and a discharge hole 122, both ends of the discharge hole 122 penetrate through the side wall of the shaft portion 12, one end of the injection hole 120 penetrates through the first end 124 of the shaft portion 12, the other end of the injection hole 120 communicates with the discharge hole 122, wherein a part of the injection molded magnet 10 is surrounded by the side wall of the shaft portion 12, another part of the injection molded magnet 10 is embedded in at least a part of the injection hole 120 and the discharge hole 122, the part of the injection molded magnet 10 located in the injection hole 120 is provided with a gate portion 100.

[0044] The magnet structure 1 is used for the motor 2, the magnet structure 1 includes injection molding magnet 10 and shaft part 12, the shaft part 12 is provided with injection molding hole 120 and discharge hole 122, one end of injection molding hole 120 penetrates the first end 124 of shaft part 12, the other end of injection molding hole 120 is communicated with discharge hole 122, in this way, when the injection molding magnet 10 structure, the material used for making injection molding magnet 10 is injected by injection molding hole 120, the material flows to the mold by discharge hole 122 to injection molding injection molding magnet 10, so that a part of injection molding magnet 10 is surrounded in the side wall of shaft part 12, another part is embedded in at least a part of injection molding hole 120 and discharge hole 122, at the same time, the gate part 100 caused by injection molding is formed in injection molding hole 120, that is, the gate part 100 is located in the middle of injection molding magnet 10, so that the each part of injection molding magnet 10 is more symmetrical in the circumferential direction of shaft part 12, thereby avoiding the influence of the shape of gate part 100 on the symmetry of the magnetic field of injection molding magnet 10, improving the symmetry of the magnetic field of injection molding magnet 10, and further improving the accuracy of the rotation angle detection.

[0045] It can be understood that when the injection molding magnet 10 is structured, the material is injected from one side of the first end 124 of the shaft part 12 through the injection molding hole 120 and flows to the discharge hole 122, and then flows to the mold through the discharge hole 122, and then forms the injection molding magnet 10, so that a part of the injection molding magnet 10 is surrounded around the side wall of the shaft part 12, and another part is formed in the discharge hole 122 and the injection molding hole 120 of the shaft part 12, and then the injection molding magnet 10 is integrally injection molded with the shaft part 12, the strength of the shaft part 12 is improved, the problem of strength caused by the injection molding hole 120 and the discharge hole 122 of the shaft part 12 is avoided, and the connection reliability between the shaft part 12 and the injection molding magnet 10 is improved.

[0046] Specifically, the injection molding magnet 10 includes a first part and a second part, the first part is surrounded around the shaft part 12, and the second part is embedded in the discharge hole 122 and the injection molding hole 120 by injection molding, wherein the first part and the second part are integrally formed by injection molding.

[0047] Optionally, the first part of the injection molding magnet 10 is annular.

[0048] Optionally, the first part of the injection molding magnet 10 forms at least a pair of magnetic poles, for example, one N pole and one S pole.

[0049] In specific application, the magnet structure 1 cooperates with the magnetoresistance element to realize the detection of the rotation angle.

[0050] As shown in Figure 2 , Figure 4 and Figure 5 in some embodiments, optionally, the gate part 100 is located in the injection molding hole 120 towards one side of the first end 124.

[0051] In this embodiment, the side of the gate portion 100 facing the first end 124 is located within the injection hole 120, ensuring that the gate portion 100 does not protrude from the injection hole 120. Consequently, the portion of the injection-molded magnet 10 located within the injection hole 120 does not protrude from the injection hole 120, thus guaranteeing the reliability of the injection molding process and preventing the injection material from flowing to other locations and affecting the symmetry of the injection-molded magnet 10. Furthermore, when the magnet structure 1 is pressed into the shaft hole 202 of the motor 2's shaft 20, it is possible to prevent the injection-molded magnet 10 from being crushed, thereby preventing the injection-molded magnet 10 from breaking.

[0052] Optionally, the gate portion 100 is symmetrically arranged with respect to the axis of the shaft portion 12.

[0053] like Figure 2 As shown, in some embodiments, optionally, the gate portion 100 includes: a first recess 102, which is recessed from the injection-molded magnet 10 toward the second end 126 of the shaft portion 12; and a second recess 104, which is located inside the first recess 102 and recessed toward the second end 126, wherein the cross-sectional area of ​​the second recess 104 is smaller than the cross-sectional area of ​​the first recess 102.

[0054] In this embodiment, the gate portion 100 includes a first recess 102 and a second recess 104. The second recess 104 is disposed in the first recess 102 and recessed towards the second end 126. The cross-sectional area of ​​the second recess 104 is smaller than that of the first recess 102, which reduces pressure loss during injection molding and allows the material to be uniformly filled in the mold, thereby improving the magnetic field uniformity of the injection-molded magnet 10.

[0055] Optionally, the first recess 102 and the second recess 104 are both circular in cross-section along the axis perpendicular to the shaft portion 12.

[0056] like Figure 4 As shown, in some embodiments, optionally, in the cross-section of the injection hole 120 and the cross-section of the shaft portion 12, the line connecting any two points on the sidewall of the shaft portion 12 that passes through the center of the shaft portion 12 is the first connecting line, and the line connecting any two points on the sidewall of the injection hole 120 that passes through the center of the shaft portion 12 is the second connecting line. The ratio of the length L2 of the second connecting line to the length L1 of the first connecting line is greater than or equal to 1 / 4 and less than or equal to 2 / 3.

[0057] In this embodiment, if the size of the injection hole 120 is too large, it will affect the strength of the shaft 12. Conversely, if the size of the injection hole 120 is too small, it will affect the material injection speed and easily cause material blockage. Therefore, the ratio of the length L2 of the second connecting line to the length L1 of the first connecting line is limited to between 1 / 4 and 2 / 3, which can ensure both the strength of the shaft 12 and the reliability of material injection.

[0058] Optionally, the center of the shaft portion 12 is the geometric center of the shaft portion 12. The center of the injection hole 120 is the geometric center of the injection hole 120.

[0059] Optionally, the cross-sectional shape of the injection hole 120 can be circular or non-circular, such as square, hexagonal, etc.

[0060] Optionally, in the case where the cross-sectional shape of the injection hole 120 is circular and the shaft portion 12 is a cylinder, the ratio of the diameter of the injection hole 120 to the diameter of the shaft portion 12 is greater than or equal to 1 / 4 and less than or equal to 2 / 3.

[0061] It should be noted that the cross section of the injection hole 120 is the cross section of the injection hole 120 perpendicular to the axis of the shaft portion 12, and the cross section of the shaft portion 12 is the cross section of the shaft portion 12 perpendicular to the axis.

[0062] Specifically, the first connecting line and the second connecting line are straight lines.

[0063] In some embodiments, optionally, the axis A of the injection hole 120 coincides with the axis B of the shaft portion 12; and / or the axis C of the discharge hole 122 coincides with the radial direction of the shaft portion 12.

[0064] In this embodiment, the axis A of the injection hole 120 coincides with the axis B of the shaft portion 12, so that the injection hole 120 is coaxially arranged with the shaft portion 12, so that the part of the injection molded magnet 10 formed in the injection hole 120 is more symmetrical relative to the axis of the shaft portion 12, improving the symmetry of the injection molded magnet 10, and further improving the detection accuracy of the motor 2 for the rotation angle of the injection molded magnet 10. The axis C of the discharge hole 122 coincides with the radial direction of the shaft portion 12, that is, the discharge hole 122 penetrates the shaft portion 12 along the radial direction of the shaft portion 12, so that the part of the injection molded magnet 10 formed in the discharge hole 122 is more symmetrical, and further improves the symmetry of the injection molded magnet 10 as a whole.

[0065] Optionally, the cross section of the discharge hole 122 is circular.

[0066] In some embodiments, optionally, the injection molded magnet 10 is symmetrically arranged along the radial direction of the shaft portion 12.

[0067] In this embodiment, the injection molded magnet 10 is symmetrically arranged along the radial direction of the shaft portion 12, improving the symmetry of the magnetic field of the injection molded magnet 10, and further improving the detection accuracy of the motor 2.

[0068] According to an embodiment of the utility model, a motor 2 is also provided, comprising: a detection piece 22; and the magnet structure 1 according to any one of the above embodiments, the magnet structure 1 can rotate relative to the detection piece 22, so that the detection piece 22 detects the angle information of the motor 2 according to the magnet structure 1.

[0069] The motor 2 provided by the utility model has all the beneficial effects of the magnet structure 1, and through cooperation of the detection member 22 and the magnet structure 1, the detection of the rotation angle of the motor 2 is realized.

[0070] Optionally, the detection member 22 comprises a magnetoresistance effect element or a Hall element, and the magnet structure 1 cooperates with the magnetoresistance effect element or the Hall element to realize the detection of the rotation angle.

[0071] Optionally, when the magnet structure 1 rotates, the magnetic field of the magnet structure 1 rotates relative to the magnetoresistance effect element, and then the magnetoresistance effect element realizes the detection of the position of the magnet structure 1 according to the different magnetic field strengths sensed.

[0072] As shown in Figure 4 , Figure 6 and Figure 7 in some embodiments, the motor 2 further comprises a rotating shaft 20, the rotating shaft 20 comprises a shaft hole 202, and the second end 126 of the shaft part 12 of the magnet structure 1 penetrates into the shaft hole 202; wherein in the cross sections of the shaft part 12 and the rotating shaft 20, among the lines connecting any two points on the side wall of the shaft part 12, the line passing through the center of the shaft part 12 is the first line, among the lines connecting any two points on the side wall of the rotating shaft 20, the line passing through the center of the rotating shaft 20 is the third line, and the ratio of the length L1 of the first line to the length L3 of the third line is greater than or equal to 1 / 4 and less than or equal to 1 / 2.

[0073] In this embodiment, the motor 2 further comprises the rotating shaft 20, the second end 126 of the shaft part 12 is installed into the shaft hole 202 of the rotating shaft 20, the installation of the motor 2 and the magnet structure 1 is realized, so that in the process of the rotation of the motor 2, the magnet structure 1 can rotate with the rotating shaft 20 through the shaft part 12, and the detection of the rotation angle of the motor 2 can be realized. When the size difference between the shaft part 12 and the rotating shaft 20 is large, the strength of the shaft part 12 is affected, and when the size difference between the shaft part 12 and the rotating shaft 20 is small, the energy consumption of the electric power steering system is increased, therefore, the ratio of the length L1 of the first line to the length L3 of the third line is set to be between 1 / 4 and 1 / 2, so that the strength of the shaft part 12 can be ensured and the energy consumption of the rotation of the motor 2 with the shaft part 12 can be reduced.

[0074] Optionally, the cross sections of the shaft part 12 and the rotating shaft 20 can be circular or non-circular.

[0075] Optionally, in the case that the shape of the cross section of the shaft portion 12 is circular and the shape of the cross section of the rotating shaft 20 is circular, the ratio of the diameter of the shaft portion 12 to the diameter of the rotating shaft 20 is greater than or equal to 1 / 4 and less than or equal to 1 / 2.

[0076] As shown in Figure 6 and Figure 7 According to one embodiment of the present application, an electric power assisted steering system is also provided, comprising the magnet structure 1 according to any one of the above embodiments, or the motor according to the above embodiments.

[0077] The electric power assisted steering system provided by the present application has all the beneficial effects of the magnet structure 1 or the motor.

[0078] According to one embodiment of the present application, a vehicle is also provided, comprising the magnet structure 1 according to any one of the above embodiments, or the motor 2 according to the above embodiments, or the electric power assisted steering system according to the above embodiments.

[0079] The vehicle provided by the present application has all the beneficial effects of the magnet structure 1 or the motor 2 or the electric power assisted steering system.

[0080] According to one embodiment of the present application, the injection molded magnet body (such as the injection molded magnet 10) has a gate portion 100 of the gate mark caused by injection molding on the first main surface side, and the gate portion 100 is on the upper side of the injection hole 120 of the shaft portion 12. In this way, the injection hole 120 can be opened on the shaft portion 12 for injection molding, which not only ensures the reliability of the shaft portion 12, but also ensures the magnetic field symmetry of the injection molded magnet body. The injection molded magnet body has very good symmetry on both sides of the center line, which can better ensure the magnetic field symmetry of the product.

[0081] The injection hole 120 and the discharge hole 122 are through, and the injection material flows into the discharge hole 122 from the injection hole 120, and then flows into the mold of the injection molded magnet body through the discharge hole 122, which ensures the flowability of the injection molded magnet body and better ensures its magnetic field symmetry.

[0082] The diameter of the shaft portion 12 is 1 / 4 to 1 / 2 of the diameter of the rotating shaft 20, and the diameter of the injection hole 120 is 1 / 4 to 2 / 3 of the diameter of the shaft portion 12, which can ensure the reliability of the shaft portion 12.

[0083] In the utility model, the term "a plurality of" refers to two or more than two, unless otherwise expressly limited. The terms "mounting", "connected", "connected", "fixed" and the like should be broadly understood, for example, "connected" can be fixedly connected, or can be detachably connected, or integrally connected; "connected" can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0084] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "a specific embodiment" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0085] The above only describes the preferred embodiments of the utility model, and is not used to limit the utility model. For those skilled in the art, the utility model can have various changes and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A magnet structure, characterized by, The magnet structure is used for an electric machine, and the magnet structure comprises: an injection molded magnet; a shaft portion provided with an injection hole and a discharge hole, two ends of the discharge hole penetrating through the sidewall of the shaft portion, one end of the injection hole penetrating through the first end of the shaft portion, and the other end of the injection hole communicating with the discharge hole, wherein a part of the injection molded magnet is arranged around the sidewall of the shaft portion, another part of the injection molded magnet is embedded in at least a part of the injection hole and the discharge hole, and the part of the injection molded magnet located in the injection hole is provided with a gate portion.

2. The magnet structure according to claim 1, characterized by The gate portion is located in the injection hole towards the side of the first end.

3. The magnet structure according to claim 2, characterized in that The gate portion comprises: a first recess recessed from the injection molded magnet towards the second end of the shaft portion; a second recess located in the first recess and recessed towards the second end, and the cross-sectional area of the second recess is smaller than that of the first recess.

4. The magnet structure according to any one of claims 1 to 3, characterized in that, In the cross section of the injection hole and the cross section of the shaft portion, among the lines connecting any two points on the sidewall of the shaft portion, the line passing through the center of the shaft portion is the first line, among the lines connecting any two points on the sidewall of the injection hole, the line passing through the center of the shaft portion is the second line, and the ratio of the length of the second line to the length of the first line is greater than or equal to 1 / 4 and less than or equal to 2 / 3.

5. The magnet structure according to any one of claims 1 to 3, characterized in that, The axis of the injection hole coincides with the axis of the shaft portion; and / or The axis of the discharge hole coincides with the radial direction of the shaft portion.

6. The magnet structure according to any one of claims 1 to 3, characterized in that, The injection molded magnet is symmetrically arranged along the radial direction of the shaft portion.

7. An electric machine characterized by comprises: a detection member; and The magnet structure according to any one of claims 1 to 6 is capable of rotating relative to the detection member, so that the detection member detects the angle information of the electric machine according to the magnet structure.

8. The electric machine of claim 7, wherein, further comprises: a rotating shaft comprising a shaft hole, the second end of the shaft portion of the magnet structure penetrating into the shaft hole; wherein, in the cross section of the shaft portion and the cross section of the rotating shaft, among the lines connecting any two points on the sidewall of the shaft portion, the line passing through the center of the shaft portion is the first line, among the lines connecting any two points on the sidewall of the rotating shaft, the line passing through the center of the rotating shaft is the third line, and the ratio of the length of the first line to the length of the third line is greater than or equal to 1 / 4 and less than or equal to 1 / 2.

9. An electric power assisted steering system characterised in that, comprises: the magnet structure according to any one of claims 1 to 6; or the electric machine according to claim 7 or 8.

10. A vehicle characterized by comprising: comprises: the magnet structure according to any one of claims 1 to 6; or the electric machine according to claim 7 or 8; or the electric power assisted steering system according to claim 9.

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