Electric machine and rotor assembly thereof

Abstract

The utility model relates to a kind of motor and its rotor assembly.Rotor assembly includes: base, including main body sleeve and the extension sleeve extending along the axial direction of main body sleeve from the first end of main body sleeve, main body sleeve has in axial direction opposite first end and second end;Magnetic ring, sleeve is set in the outside of main body sleeve and is fixedly connected with main body sleeve;For main shaft to pass through in axial direction plug-like piece, fixed in the inner hole of main body sleeve, plug-like piece includes: first portion, second portion and third portion sequentially arranged from second end along axial direction, the shaft hole of first portion and third portion is respectively with main shaft gap cooperation, second portion is equipped with: for the elastic sheet of elastic cooperation with the main shaft of plug-like piece into.This utility model reduces the friction and collision between main shaft and shaft hole, effectively reduce the noise generated when motor works.

Description

Technical Field

[0001] This utility model relates to an electric motor and its rotor assembly. Background Technology

[0002] Electric motors (such as stepper motors) are widely used in various automated equipment and instruments. The structural design of the rotor assembly of a stepper motor directly affects the motor's operating performance. Generally, the rotor assembly adopts a one-piece injection-molded structure, which makes it easy for parts to collide with each other during operation and generate more noise. Utility Model Content

[0003] At least one embodiment of this utility model provides a rotor assembly for an electric motor, comprising: a base including a main sleeve and an extension sleeve extending axially from a first end of the main sleeve along the main sleeve, the main sleeve having a first end and a second end opposite to each other in the axial direction, the extension sleeve having a first shaft hole through which the main shaft of the motor passes along the axial direction; a magnetic ring sleeved on the outside of the main sleeve and fixedly connected to the main sleeve; a plug-like member for which the main shaft passes along the axial direction and fixed in the inner hole of the main sleeve, wherein the plug-like member comprises: a first portion, a second portion and a third portion arranged sequentially from the second end along the axial direction; wherein the second shaft hole of the first portion is clearance-fitted with the main shaft, the third shaft hole of the third portion is clearance-fitted with the main shaft, and the second portion is provided with: a spring piece for contacting the surface of the main shaft that passes through the plug-like member to elastically engage with the main shaft.

[0004] For example, in a rotor assembly provided in at least one embodiment of the present invention, the spring sheet and the plug-like member are integrally formed.

[0005] For example, in a rotor assembly provided in at least one embodiment of the present invention, the spring plate extends integrally along the axial direction, the spring plate has a free end and a connecting end opposite each other in the axial direction, the free end being closer to the center line of the second shaft hole of the first portion relative to the connecting end.

[0006] For example, in a rotor assembly provided in at least one embodiment of the present invention, the connecting end is located at one end of the second part near the first part, and the radial distance of the connecting end is equal to the inner diameter of the second shaft hole of the first part.

[0007] For example, in a rotor assembly provided in at least one embodiment of the present invention, the spring includes a plurality of bullet pieces arranged at intervals in the circumferential direction.

[0008] For example, in a rotor assembly provided in at least one embodiment of the present invention, the plurality of bullet pieces include a first bullet piece and a second bullet piece disposed radially opposite to each other along the plug-like member.

[0009] For example, in a rotor assembly provided in at least one embodiment of the present invention, the second portion forms a first cavity by perforating along the radial direction of the plug-like member, the perforation forming two openings opposite each other along the radial direction of the plug-like member.

[0010] For example, in a rotor assembly provided in at least one embodiment of the present invention, the first bullet piece and the second bullet piece are disposed at the junction of the first cavity and the second shaft hole of the first portion.

[0011] For example, in a rotor assembly provided in at least one embodiment of the present invention, the cross-section of the opening is square.

[0012] For example, in a rotor assembly provided in at least one embodiment of the present invention, the spring is inclined relative to the axial direction, and the angle between the extension direction of the spring and the axial direction is 5° to 30°.

[0013] For example, in a rotor assembly provided in at least one embodiment of the present invention, a flared chamfer is provided at the end of the second shaft hole of the first part away from the second part, and a double chamfer is provided at the end of the third shaft hole of the third part near the second part.

[0014] For example, in a rotor assembly provided in at least one embodiment of the present invention, the outer end of the third portion on the side away from the second portion is provided with a chamfer.

[0015] For example, in a rotor assembly provided in at least one embodiment of the present invention, the third part is provided with a tapered guide groove, the tapered guide groove is located on the side of the third shaft hole of the third part away from the second part, and the tapered guide groove is connected to the third shaft hole of the third part so that the main shaft can pass through along the axial direction.

[0016] For example, in a rotor assembly provided in at least one embodiment of the present invention, the ratio of the radial distance of the free end of the spring in the free state to the outer diameter of the main shaft is 0.95-0.97.

[0017] For example, in a rotor assembly provided in at least one embodiment of the present invention, the plug-like member includes a base and a boss. The boss includes a first segment, a second segment, and a third segment of the first portion arranged sequentially in the axial direction. The base is the remaining portion of the first portion excluding the first segment. The inner hole of the main sleeve includes a first hole that corresponds to and engages with the base and a second hole that corresponds to and engages with the boss. The inner diameter of the first hole is larger than the inner diameter of the second hole. The inner diameter of the second hole is smaller than the outer diameter of the boss.

[0018] For example, in a rotor assembly provided in at least one embodiment of the present invention, the length of the second hole in the axial direction is greater than the length of the boss in the axial direction, so that the third part and the inner hole of the main body sleeve form a first suspended area, and the first cavity is a second suspended area.

[0019] For example, in a rotor assembly provided in at least one embodiment of the present invention, the free end of the spring plate is chamfered.

[0020] For example, in a rotor assembly provided in at least one embodiment of the present invention, the spring plate extends radially along the plug-like member and has an inner arc surface; the radius of the arc surface at the end near the first part along the axial direction is equal to the inner diameter of the second shaft hole of the first part, and the radius of the arc surface at the end away from the first part along the axial direction is smaller than the inner diameter of the second shaft hole of the first part.

[0021] For example, in a rotor assembly provided in at least one embodiment of the present invention, the second portion forms a first cavity by perforating radially upward along the plug-like member; the spring includes: at least one first arc-shaped spring disposed on a first inner sidewall in the first cavity, and at least one second arc-shaped spring disposed on a second inner sidewall in the first cavity opposite to the first inner sidewall, the first arc-shaped spring and / or the second arc-shaped spring respectively extending radially along the plug-like member and having an inner arc surface; the first arc-shaped spring and the second arc-shaped spring are disposed opposite to each other so that the surfaces of the first arc-shaped spring and the second arc-shaped spring respectively contact the surfaces opposite to the main shaft.

[0022] At least one embodiment of the present invention also provides a motor, including a rotor assembly as described in any of the above claims, the motor further including the main shaft, and the motor being a stepper motor. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a stepper motor provided for some embodiments of the present invention.

[0025] Figure 2 Exploded view of a rotor assembly provided for some embodiments of this utility model.

[0026] Figure 3 This is a perspective view of a plug-like component provided in some embodiments of the present invention.

[0027] Figure 4 This is a cross-sectional view of a plug-like component provided in some embodiments of the present invention.

[0028] Figure 5 This is a schematic diagram illustrating the spring clip arrangement provided in some embodiments of the present invention.

[0029] Figures 6-7 This is a cross-sectional view of a plug-like component provided in some other embodiments of the present invention.

[0030] Figure 8 This is a schematic diagram of the structure of the plug-like component installed in the substrate according to some embodiments of the present invention.

[0031] Figure 9 The diagram shows the structure of the substrate and magnetic ring provided in some embodiments of this utility model.

[0032] Figures 10-11 This is a cross-sectional view of a plug-like component provided in some embodiments of the present invention.

[0033] Figure 12 for Figure 11 A schematic diagram of a local structure.

[0034] Figures 13-14 This is a schematic diagram illustrating the spring arrangement provided in some other embodiments of the present invention. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] Unless otherwise defined, all terms (including technical and scientific terms) used in the embodiments of this utility model shall have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model pertains. It should also be understood that terms such as those defined in a common dictionary shall be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and shall not be interpreted in an idealized or highly formalized sense, unless expressly defined in the embodiments of this utility model.

[0037] The terms "first," "second," and similar words used in the embodiments of this utility model do not indicate any order, quantity, or importance, but are only used to distinguish different components. Terms such as "a," "one," or "the" do not indicate a quantity limitation, but rather indicate the presence of at least one. Similarly, terms such as "including" or "comprising" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "inner," "outer," "upper," and "lower" 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. In the embodiments of this utility model, the term "about" as used herein means that the numerical value is approximate and small changes will not significantly affect the practice of the aspects disclosed in this utility model; the embodiments of this utility model do not specify numerical limitations. The drawings in this utility model are not strictly drawn to scale; the specific dimensions and quantity of each structure can be determined according to actual needs. The accompanying drawings described in this utility model are merely structural schematic diagrams.

[0038] The terms "parallel" and "identical" used in this invention include both strictly defined meanings and nuances such as "substantially parallel" and "substantially identical," which encompass a certain degree of error. These terms take into account measurement and errors associated with the measurement of a specific quantity (e.g., limitations of the measurement system), and represent the acceptable deviation range for a specific value as determined by a person skilled in the art. For example, "substantially" can mean within one or more standard deviations, and unless otherwise specified, can mean within 10% or 5% of the deviation of the value.

[0039] Currently, most rotor assemblies adopt a one-piece injection-molded structure, resulting in poor control over the consistency of the central hole diameter. This is because the rotor injection hole diameter is relatively long and the wall thickness is uneven, with less material at the top and more at the bottom, leading to inconsistent shrinkage rates and irregular hole shapes and sizes. Therefore, during high-speed operation, the rotor's centrifugal force causes the rotor's central shaft (also known as the main shaft) to oscillate, and there is a lack of lubrication between them. Consequently, the rotor's central shaft, rotor holes, and cover plate holes are prone to collisions, especially radially, resulting in significant noise during high-speed rotation.

[0040] In response, at least one embodiment of the present invention provides a rotor assembly for an electric motor, comprising: a base, including a main sleeve and an extension sleeve extending axially from a first end of the main sleeve along the main sleeve; the main sleeve having a first end and a second end opposite to each other in the axial direction; the extension sleeve having a first shaft hole through which the main shaft of the motor passes in the axial direction; a magnetic ring, sleeved on the outside of the main sleeve and fixedly connected to the main sleeve; and a plug-like member for the main shaft to pass through in the axial direction, fixed in the inner hole of the main sleeve, wherein the plug-like member comprises: a first part, a second part, and a third part arranged sequentially from the second end in the axial direction; wherein the second shaft hole of the first part is clearance-fitted with the main shaft, the third shaft hole of the third part is clearance-fitted with the main shaft, and the second part is provided with: a spring piece for contacting the surface of the main shaft that passes through the plug-like member to elastically engage with the main shaft.

[0041] The plug-like component of this utility model is designed with three parts: upper, middle, and lower. The spring piece is placed in the middle of the plug-like component, so that the upper part of the plug-like component can correct the position of the spindle after passing through the spring piece, so that the center line of the spindle is as consistent as possible with the center line of the base shaft hole. This plays a guiding role in the installation of the spindle and the base shaft hole, which facilitates automated assembly. Moreover, when the spring piece elastically and adaptively grips the spindle, there is almost no collision or noise between the spindle and the shaft hole.

[0042] In embodiments of this utility model, the term "inner side" or "inward" refers to the side closer to the centerline of the device or component, and the term "outer side" or "outward" refers to the side further away from the centerline of the device or component. In embodiments of this utility model, "axial direction" refers to the direction of the central axis of the device or component. It should be noted that these definitions are for convenience of expression only and should not be construed as limitations of this utility model.

[0043] The embodiments and examples of this utility model will now be described in detail with reference to the accompanying drawings.

[0044] Figure 1 This is a schematic diagram of the structure of a stepper motor provided for some embodiments of the present invention.

[0045] For example, such as Figure 1As shown, at least one embodiment of this utility model provides a motor 1000, which can be a stepper motor. The motor 1000 may include components such as a rotor assembly 100, a main shaft 200, a housing 300, a coil assembly 400, a gearbox 500, an upper electrode plate fixing plate assembly 600, an output shaft assembly 700, and an upper cover plate 800.

[0046] In some examples, the assembly sequence of the motor 1000 may include: riveting the spindle 200 to the housing 300; installing the coil assembly 400; fitting the rotor assembly 100 onto the spindle 200, thereby installing it inside the rotor cavity of the coil assembly 400; installing the upper electrode plate fixing plate assembly 600; installing the gearbox 500 and output shaft assembly 700; and installing the upper cover plate 800.

[0047] It should be noted that, apart from the rotor assembly 100 and the main shaft 200, the other parts of the motor 1000 of this utility model are not the focus of this utility model. They can be referred to the description of the existing technical solutions, and will not be specifically shown or described in this article.

[0048] Figure 2 Exploded view of a rotor assembly provided for some embodiments of this utility model.

[0049] For example, such as Figure 2 As shown, the rotor assembly 100 includes a base 1, a magnetic ring 2, and a plug-like member 3. For example, the base 1 can be an injection-molded body, which may also be referred to as a rotor injection-molded body.

[0050] For example, such as Figure 2 As shown, the base 1 includes a main sleeve 11 and an extension sleeve 12 extending from a first end 1A of the main sleeve 11 along the axial direction D1 of the main sleeve 11. The main sleeve 11 has a first end 1A and a second end 1B opposite each other in the axial direction D1. The extension sleeve 12 is provided with a first shaft hole through which the main shaft 200 of the motor 1000 passes in the axial direction D1 (see below). Figure 8 The first shaft hole 121 is shown. The magnetic ring 2 is sleeved on the outside of the main body sleeve 11 and is fixedly connected to the main body sleeve 11.

[0051] In some embodiments of this utility model, the magnetic ring 2 and the main sleeve 11 are fixedly connected. This can be achieved by fastening the connection with mechanical connectors, or by injection molding the magnetic ring 2 and the main sleeve 11 into one piece to achieve the connection between the two. The embodiments of this utility model do not limit this.

[0052] In the embodiments of this utility model, the axial direction D1 of the main sleeve 11 can represent the axial direction of the entire base 1. The axial direction D1 can be understood as the overall extension direction of the entire base 1. The axial direction D1 of the main sleeve 11 is consistent with the axial direction of the extension sleeve 12 and the axial direction of the plug 3 installed on the main sleeve 11.

[0053] Figure 3 This is a perspective view of a plug-like component provided in some embodiments of the present invention. Figure 4 This is a cross-sectional view of a plug-like component provided in some embodiments of the present invention. Figure 5 This is a schematic diagram illustrating the spring clip arrangement provided in some embodiments of the present invention. Figures 6-7 This is a cross-sectional view of a plug-like component provided in some other embodiments of the present invention. Figure 6 and Figure 7 Show and Figure 4 Same characteristics, but Figure 6 and Figure 7 Added and Figure 4 Different markers. Figure 8 This is a schematic diagram of the structure of the plug-like component installed in the substrate according to some embodiments of the present invention.

[0054] For example, such as Figures 2-8 As shown, the plug-like member 3 allows the main shaft 200 to pass through along the axial direction D1. The plug-like member 3 is fixed in the inner hole 14 of the main body sleeve 11. The plug-like member 3 includes a first part 31, a second part 32 and a third part 33 arranged sequentially from the second end 1B of the main body sleeve 11 along the axial direction D1.

[0055] In an embodiment of this utility model, the second part 32 of the plug-like member 3 is the part located between the first part 31 and the third part 33.

[0056] For ease of description, the first part 31 can be referred to as the lower part of the plug 3, the second part 32 can be referred to as the middle part (i.e., the middle section) of the plug 3, and the third part 33 can be referred to as the upper part of the plug 3.

[0057] In an embodiment of this utility model, the plug-like member 3 is installed at one end of the inner cavity of the base 1, and the second end 1B of the main sleeve 11 can be referred to as the inlet end of the plug-like member 3.

[0058] In embodiments of this utility model, the plug-like component 3 refers to a part having a "plug"-like shape. For example, the plug-like component 3 has a relatively large base and a relatively small boss, as detailed below. The plug-like component 3 of this utility model is fixedly disposed within the base 1; therefore, the plug-like component 3 can also be referred to as a fixed plug.

[0059] For example, such as Figure 4 and Figure 8As shown, the second shaft hole 311 of the first part 31 is clearance-fitted with the main shaft 200, and the third shaft hole 331 of the third part 33 is clearance-fitted with the main shaft 200. The first shaft hole 121 of the extension sleeve 12 is also clearance-fitted with the main shaft 200. In some embodiments of this utility model, the second shaft hole 311 of the first part 31 and the third shaft hole 331 of the third part 33 are both shaft holes of the base 1.

[0060] In some embodiments of this utility model, the plug-like member 3 and the base 1 are provided with shaft holes with an inner diameter consistent with that of the main shaft 200, that is, the inner diameter of the second shaft hole 311 of the first part 31 can be equal to the inner diameter of the third shaft hole 331 of the third part 33, and the second shaft hole 311 and the third shaft hole 331 (e.g. Figure 4 As shown, the diameter of the third shaft hole 331 (diameter B) is the same as the inner diameter of the first shaft hole 121.

[0061] For example, such as Figure 4 and Figure 8 As shown, the second part 32 is provided with a spring 4 for contacting the surface of the spindle 200 that is inserted into the plug 3 to elastically engage with the spindle 200.

[0062] The spring sheet 4 of this invention is a structure with elastic deformation capability (such as being made of a material with elastic deformation capability). For example, the spring sheet 4 can maintain its initial free state when not subjected to external force, and when subjected to external pressure, the spring sheet 4 will generate elastic displacement in the corresponding direction (e.g., outward displacement), and automatically recover after the external force is removed.

[0063] In an embodiment of this utility model, since a spring piece 4 is provided in the second part 32, the radial distance between the spring piece 4 and the main shaft 200 can be set to be less than the outer diameter of the main shaft 200. Therefore, the spring piece 4 can adaptively grip the main shaft 200 through elastic deformation, resulting in a tighter contact between the spring piece 4 and the main shaft 200.

[0064] In some examples, the spring 4 extends along the axial direction D1 (for example, the spring 4 may be slightly inclined relative to the axial direction D1), and the spring 4 has a free end 4A and a connecting end 4B opposite each other in the axial direction D1; in the free state, the free end 4A of the spring 4 is closer to the center line O1 of the second shaft hole 311 of the first part 31 than the connecting end 4B. The center line O1 extends in the same direction as the axial direction D1.

[0065] In the embodiments of this utility model, the free end 4A of the spring 4 is closer to the center line O1 of the second shaft hole 311 of the first part 31 than the connecting end 4B of the spring 4. This can be understood as the free end 4A of the spring 4 being more inward than the connecting end 4B in the free state. That is, the spring 4 of this utility model can form a structure design that is narrow at the top and wide at the bottom. Moreover, in the free state, the radial distance A of the free end 4A of the spring 4 (i.e., the radial distance A of the outlet end of the spring 4 in the free state) is smaller than the diameter B of the shaft hole. Figure 4 As shown.

[0066] In an embodiment of this utility model, the center line O1 of the second shaft hole 311 of the first part 31 coincides with the center line of the entire plug-shaped member 3.

[0067] In the embodiments of this utility model, when describing the spring piece 4, "radial" refers to the straight line direction along the radial direction of the spring piece with a circular cross-section; or, perpendicular to the axial direction and based on the common center of the circumferential distribution of multiple bullet pieces in the spring piece (i.e., the virtual center of the virtual circle), extending along the radial direction.

[0068] In some examples, the shrapnel 4 may include multiple shrapnel pieces (see the description below for details), with the free end and / or connecting end of each shrapnel piece 4 having an arc-shaped profile.

[0069] In some examples, the spring 4 comprises multiple bullet fragments. Since these multiple bullet fragments are arranged circumferentially, their distribution can be considered as lying on a virtual circle. Thus, in some embodiments of this invention, the radial distance between the free end 4A or the connecting end 4B of the spring 4 refers to the diameter of the virtual circle containing the corresponding ends of the circumferentially distributed multiple bullet fragments. For example, when the multiple bullet fragments of the spring 4 are two bullet fragments, the radial distance between the free end 4A of the spring 4 is the aforementioned distance A (e.g., ...). Figure 4 (as shown). For example, if there are three or more bullet fragments in the multiple bullet fragments of the bullet fragment 4, the radial distance of the free end 4A of the bullet fragment 4 is the diameter of the virtual circle in which the free ends of the three or more bullet fragments are located.

[0070] For example, such as Figure 4 and Figure 5 As shown, the connecting end 4B of the spring piece 4 is located at the end of the second part 32 closer to the first part 31. This can be understood as the connecting end 4B of the spring piece 4 being located at the junction of the first part 31 and the second part 32. For example, the connecting end 4B is the starting point of the extension of the spring piece 4, and the radial distance of the connecting end 4B of the spring piece 4 is equal to the inner diameter of the second shaft hole 311 of the first part 31. That is, the radial dimension at the starting point of the extension of the spring piece 4 is set to be equal to the inner diameter of the second shaft hole 311 of the first part 31.

[0071] In some examples, when the spindle 200 passes through the plug 3, the spring 4 is compressed. The spring 4 can adaptively grip the spindle 200 through elastic deformation, making the contact between the spring 4 and the spindle 200 tighter, reducing the friction and collision between the spindle and the shaft hole, and effectively reducing the noise generated by the motor during operation.

[0072] The plug-like component 3 of this invention is divided into three parts: upper, middle, and lower. A spring plate 4 is positioned in the middle of the plug-like component 3. The upper part of the plug-like component 3 can correct the position of the spindle 200 after it passes through the spring plate, ensuring that the center line of the spindle is as consistent as possible with the center line of the base shaft hole. This guides the installation of the spindle and the base shaft hole, facilitating automated assembly. Furthermore, after these two center lines are aligned, the circumferential gap between the spindle and the shaft hole is uniform. With the spring plate elastically and adaptively gripping the spindle, there is almost no collision or noise between the spindle and the shaft hole.

[0073] The overall mechanical stability of the plug-like component 3 in the above embodiments of this utility model is improved, which can prevent the spring from loosening and shifting, and the service life of the spring is longer.

[0074] The research of this utility model found that in the case of a solution that uses a spring sheet instead of a plug-like part 3, most of the radial force of the main shaft is borne by the spring sheet when the motor rotates. Long-term high-speed operation leads to the weakening or even breakage of the spring sheet's elasticity, loss of buffering function, and a significant increase in noise over time.

[0075] The research of this utility model also found that, in the case of using a spring sheet for the upper part of the plug-shaped part 3, if there is a machining error in the spring sheet after the spindle 200 passes through it during assembly, the center line of the spindle 200 and the center line of the inner hole of the base 1 may be offset after the spring sheet clamps the spindle 200. When the upper end of the spindle 200 is installed into the inner hole of the injection molded body, the assembly will be hindered, which is not convenient for automated production. At the same time, when the center lines of the two are offset during assembly, the spindle 200 will scratch the inner hole of the injection molded body, and the gap between the spindle 200 and the injection molded body will increase, which will easily cause collision and noise during motor operation. However, since the plug-shaped member 3 of the above embodiment of the present invention is divided into three parts, namely upper, middle and lower, and the upper part of the plug-shaped member 3 is added and the spring piece 4 is placed in the middle part of the plug-shaped member 3, the present invention can align the spindle 200 after passing through the spring piece with the center line of the base shaft hole, which is convenient for automated installation. After the two center lines are aligned, the circumferential gap between the spindle 200 and the base 1 of the rotor assembly 100 is uniform. Moreover, when the spring piece elastically holds the spindle 200, there is almost no collision or noise between the spindle 200 and the base 1.

[0076] In this embodiment of the invention, the plug-like component 3 is divided into upper, middle, and lower parts. An upper part of the plug-like component 3 is added, while the spring piece 4 is positioned in the middle part. This results in the plug-like component 3 having additional features such as an end-plane adsorption area and a cavity gripper slot for grasping. This allows it to be compatible with various standardized, universal automated fixtures during product automated assembly preparation and assembly processes. Thus, there is no need to customize special fixtures, reducing the cost of automated production line modifications and improving production efficiency. The stable gripping force avoids assembly misalignment or component damage caused by unstable gripping, thereby improving the automated yield rate.

[0077] In some examples, the spring 4 and the plug 3 are integrally molded. This makes the machining of the plug 3 very convenient. For example, the spring 4 and the plug 3 can be injection molded as a single unit.

[0078] In some examples, the shrapnel 4 includes a plurality of shrapnel pieces 401 arranged at intervals in the circumferential direction. For example, the plurality of shrapnel pieces 401 may be two shrapnel pieces 401 or three or more shrapnel pieces 401. For example, the plurality of shrapnel pieces 401 may be arranged at even intervals in the circumferential direction.

[0079] For example, such as Figure 4 and Figure 5 As shown, the plurality of bullet fragments 401 include a first bullet fragment 41 and a second bullet fragment 42 disposed radially opposite to each other along the plug-like member 3.

[0080] For example, such as Figure 3 and Figure 5 As shown, the second part 32 of the plug 3 forms a first cavity 32A by a perforation along the radial direction of the plug 3, the perforation forming two openings 321 opposite each other along the radial direction of the plug 3.

[0081] In this embodiment of the invention, a cavity is opened in the plug-shaped member 3. This design not only reduces the use of materials to save costs, but also allows for oil storage, continuous lubrication of the contact surface with the spindle, and extends the service life of the rotor assembly 100, while further reducing noise.

[0082] For example, such as Figure 4 and Figure 5 As shown, the first bullet piece 41 and the second bullet piece 42 are disposed at the junction 501 of the shaft hole of the second shaft hole 311 of the first cavity 32A and the first part 31, that is, the junction 501 is the starting point for the extension of the bullet piece 4; for example, the first bullet piece 41 and the second bullet piece 42 are evenly arranged circumferentially at the junction 501. For example, the first bullet piece 41 and the second bullet piece 42 each have a free end and a connecting end opposite each other along the axial direction D1, and the connecting end of the first bullet piece 41 and the connecting end of the second bullet piece 42 are both connected to the junction 501.

[0083] For example, the first bullet piece 41 and the second bullet piece 42 are symmetrical with respect to the center line O1 of the second shaft hole 311 of the first part 31. In this way, the structural design is simple, the center line alignment is better, and noise is reduced more effectively.

[0084] For example, such as Figure 3 and Figure 4 As shown, the cross-section of opening 321 is square. Of course, this is merely exemplary and is not a limitation of the embodiments of this utility model.

[0085] For example, such as Figure 4 As shown, the spring 4 is inclined relative to the axial direction D1, and the angle between the extension direction of the spring 4 and the axial direction D1 / center line O1 is 5°~30°.

[0086] For example, such as Figure 6 As shown, a flared chamfer is provided at the end 301A of the second shaft hole 311 away from the second portion 32 (i.e., the entrance of the second shaft hole 311), so that the first portion 31 forms a guide portion (which can be referred to as the first guide portion 301) located on the side away from the second portion 32. For example, the flared chamfer has a rounded transition, forming a guide surface that converges towards the center of the second shaft hole 311. The flared chamfer can guide the spindle 200 to automatically align with the center of the shaft hole, correct the insertion angle deviation, and reduce rigid collisions.

[0087] For example, such as Figure 6 As shown, a double-step chamfer is provided at one end 303A of the third shaft hole 331 near the second part 32 (i.e., at the entrance of the third shaft hole 331), so that the third part 33 forms a guide portion (which can be referred to as the third guide portion) located on the side near the second part 32. For example, the double-step chamfer refers to a combination of two chamfers with different angles, which includes a first chamfer 303A1 and a second chamfer 303A2.

[0088] The first chamfer 303A1 is closer to the upper end of the third shaft hole 331 than the second chamfer 303A2. The angle of the first chamfer 303A1 is steeper than that of the second chamfer 303A2, and the first chamfer 303A1 can form an open guide entrance. The angle of the second chamfer 303A2 is gentler than that of the first chamfer 303A1, and the second chamfer 303A2 transitions smoothly with the inner wall of the shaft hole.

[0089] For example, such as Figure 6 As shown, the first bullet piece 41 and the second bullet piece 42 can serve as a second guide. Thus, when the main shaft 200 passes through the bullet piece 4, the oblique guide surface of the bullet piece 4 generates a radial constraint force through elastic deformation, which can dynamically correct the position of the main shaft and keep it as centered as possible.

[0090] In some embodiments of this utility model, the first guide part can serve as an assembly "entry point" to guide the spindle 200 to quickly align with the shaft hole through the trumpet-shaped entry point, reducing initial impact; the second guide part can serve as a "dynamic centering" point to correct the spindle deviation in real time using an elastic angle, providing continuous and stable support; the third guide part can serve as an "end calibrator" to ensure the spindle passes through accurately through a stepped structure, eliminating residual eccentricity.

[0091] Therefore, the three guide parts designed in the embodiment of this utility model achieve no rigid contact throughout the spindle assembly process through the flexible cooperation of guidance, centering and calibration. This can structurally eliminate the impact risk caused by assembly deviation, significantly improve the quietness performance of the motor, and is suitable for automated production.

[0092] For example, such as Figure 7 As shown, the outer end portion 302B of the third part 33, on the side away from the second part 32, is chamfered. In this embodiment of the invention, the outer circular end of the upper part of the plug-like member 3 is designed with a chamfer, which can guide the plug-like member 3 to be quickly inserted into the base 1, thereby avoiding jamming due to angular deviation during insertion and reducing assembly resistance.

[0093] For example, such as Figure 7 As shown, the third part 33 has a tapered guide groove 332. The tapered guide groove 332 is located on the side of the third shaft hole 331 away from the second part 32 (that is, the tapered guide groove 332 is located at the upper part of the third part 33), and the tapered guide groove 332 is connected to the third shaft hole 331 of the third part 33 so that the main shaft 200 can pass through along the axial direction D1.

[0094] In this embodiment of the invention, a tapered guide groove is designed on the top of the plug-shaped part 3. In this way, the centrifugal force of the motor rotation can be used to deliver grease to the top of the spindle, guide the grease to flow along the spindle axis, and evenly cover the entire contact surface of the spindle, avoiding abnormal wear and noise caused by insufficient local lubrication; thus, the coefficient of friction is greatly reduced, which can suppress intermittent impacts caused by thermal expansion and extend the service life of the spindle.

[0095] In some examples, the ratio of the radial distance of the free end 4A of the spring 4 (the free end 4A in the free state) (i.e., the minimum radial distance of the entire spring 4, i.e., the distance A mentioned above) to the outer diameter of the main shaft 200 is 0.95-0.97. For example, the free end 4A of the spring 4 (i.e., the upper end of the spring 4) can be understood as the end point of the extension of the spring 4. In the embodiments of this utility model, the radial distance of the spring 4 from the starting point to the end point gradually decreases.

[0096] The embodiments of this utility model can solve the noise problem by setting a reasonable spring size, which has advantages in assembly and greatly improves efficiency. For example, the spring clamping force is uniform, the spindle is stable and does not wobble, the noise is low and consistent, meeting the requirements of silent design; the equipment can adopt constant force assembly, reducing damage such as spring breakage and spindle scratches, improving the first-pass yield; the automation process is simplified, unnecessary monitoring links are eliminated, the production cycle is stable, the abnormal downtime rate is greatly reduced, and the cost of manual intervention is reduced.

[0097] Figure 9 The diagram shows the structure of the substrate and magnetic ring provided in some embodiments of this utility model. Figures 10-11 This is a cross-sectional view of a plug-like component provided in some embodiments of the present invention. Figure 10 and Figure 11 Show and Figure 4 Same characteristics, but Figure 10 and Figure 11 Added and Figure 4 Different markers. Figure 12 for Figure 11 A schematic diagram of a local structure.

[0098] For example, such as Figure 3 and Figure 10 As shown, the plug-like member 3 includes a base 31a and a boss 31b. The boss 31b includes a first segment 31d, a second segment 32 and a third segment 33 of a first part 31 arranged sequentially in the axial direction D1. The base 31a is the remaining part 31e of the first part 31 excluding the first segment 31d.

[0099] For example, such as Figure 9 and Figure 10 As shown, the inner hole 14 of the main sleeve 11 includes: a first hole 141 that corresponds to and engages with the base 31a and a second hole 142 that corresponds to and engages with the boss 31b, wherein the inner diameter of the first hole 141 is larger than the inner diameter of the second hole 142.

[0100] For example, such as Figure 8 and Figure 9 As shown, the inner diameter C01 of the second hole 142 of the main sleeve 11 is smaller than the outer diameter c02 of the boss 31b of the plug 3.

[0101] For example, such as Figure 9 and Figure 10 As shown, the length D01 of the second hole 142 in the axial direction D1 is greater than the length d02 of the boss 31b in the axial direction D1, so that the third part 33 and the inner hole 14 of the main sleeve 11 form a first suspended area T1, wherein the first cavity 32A is a second suspended area T2.

[0102] In the above embodiments of this invention, the boss 31b of the plug-like component 3 and the hollow cavity of the base 1 are radially interference-fitted, which can prevent the spindle 100 from displacing due to external factors such as vibration. Furthermore, the lower part of the plug-like component 3 is positioned by a step, and the upper part is a certain distance from the base 1, forming a first suspended area T1. The plug-like component 3 in the embodiments of this invention has precise axial and radial positioning, which can avoid noise caused by displacement; the interference fit enhances structural rigidity and reduces the risk of resonance; and it also eliminates the need for additional fasteners, simplifying installation.

[0103] In this embodiment of the invention, local suspended areas are designed within the inner cavity of the substrate and the plug-like component. This allows the main shaft 200 to connect to the rotor assembly 100 only through a few contact points (e.g., spring 4), thus reducing the contact area between the main shaft and the fixed structure and forming an air buffer layer. This reduces frictional loss, shortens the vibration transmission path, and significantly reduces operating noise. These two suspended areas can also store oil, extending service life.

[0104] For example, such as Figure 12 As shown, the free end 4A of the spring piece 4 has a chamfer 4A1.

[0105] This invention features a chamfered transition at the end of the spring contact, preventing the right angle at the spring contact end from easily scratching the spindle surface and thus avoiding particle wear and friction noise. In this way, the chamfered surface reduces stress concentration, lowers the risk of spindle surface damage, reduces friction, extends the service life of the spindle and spring contact, and reduces noise.

[0106] Figures 13-14 This is a schematic diagram illustrating the spring arrangement provided in some other embodiments of the present invention.

[0107] In other examples, the spring 4 extends radially along the plug 3 and has an inner arc surface, so that the spring 4 can be designed as a structure that is narrow at the top and wide at the bottom.

[0108] For example, such as Figure 13 and Figure 14 As shown, the second portion 32 of the plug-like member 3 forms a first cavity 32A by a perforation along the radial direction of the plug-like member 3. The spring piece 4 includes: at least one first arcuate spring piece 43 disposed on a first inner wall 3201 in the first cavity 32A, and at least one second arcuate spring piece 44 disposed on a second inner wall 3202 opposite to the first inner wall 3201 in the first cavity 32A. The first arcuate spring piece 43 and / or the second arcuate spring piece 44 extend radially along the plug-like member 3 and have an arcuate inner surface. The first arcuate spring piece 43 and the second arcuate spring piece 44 are disposed opposite to each other so that the surfaces of the first arcuate spring piece 43 and the second arcuate spring piece 44 that are opposite to the main shaft 200 are in contact.

[0109] For example, the direction in which the second inner wall 3202 and the first inner wall 3201 face each other is perpendicular to the perforation direction corresponding to the first cavity 32A; the extension direction of each arc-shaped spring piece 44 is perpendicular to the corresponding inner wall.

[0110] For example, such as Figure 13 and Figure 14 As shown, the radius R1 of the arc surface of the spring 4 (such as the arc surface of each first arc spring 43 and / or the arc surface of the second arc spring 44) at the end near the first part 31 along the axial direction D1 (also referred to as the bottom surface of the arc spring, which refers to the side near the first part 31 of the plug 3) is equal to the inner diameter R2 of the second shaft hole 311 of the first part 31 (i.e., R1=R2); the radius R3 of the arc surface of the spring 4 (such as the arc surface of each first arc spring 43 and / or the arc surface of the second arc spring 44) at the end away from the first part 31 along the axial direction D1 (also referred to as the top surface of the arc spring, which refers to the side near the third part 33 of the plug 3) is smaller than the inner diameter R2 of the second shaft hole 311 of the first part 31 (for example, R3 is slightly smaller than R2, i.e., R3<R2). In this way, the spring 4 can form a curved surface structure that is narrow at the top and wide at the bottom.

[0111] In some examples, the first arc has the same center as the second shaft hole 311 of the first portion 31. For example, the first arc of the first arc-shaped spring 43 has the same center as the shaft hole 311 of the first portion 31, and / or, the first arc of the second arc-shaped spring 44 has the same center as the second shaft hole 311 of the first portion 31.

[0112] The embodiments of this invention employ an arc-shaped spring sheet, and apply a radial centripetal constraint force to the spindle through compressive elastic deformation, stably positioning the spindle at the center of the shaft hole. This significantly reduces the impact noise between the spindle and rotor assembly, improving the motor's quietness; it also reduces component wear, extending service life; furthermore, it enhances the spindle's operational stability and improves the motor's operational accuracy.

[0113] In some examples, the at least one first arc-shaped spring piece 43 described above can be one or more first arc-shaped spring pieces 43, that is, the present invention can provide one or more arc-shaped spring pieces on the first inner wall 3201 in the first cavity 32A. Similarly, the at least one second arc-shaped spring piece 44 described above can be one or more second arc-shaped spring pieces 44, that is, the present invention can provide one or more arc-shaped spring pieces on the second inner wall 3202 in the first cavity 32A. For example, the number of first arc-shaped spring pieces 43 can be the same as or different from the number of second arc-shaped spring pieces 44, depending on the actual situation.

[0114] In some examples, the assembly sequence of the rotor assembly 100 may be as follows: the magnetic ring 2 is injection molded integrally with the base 1, then oil is injected into the cavity of the base 1, and then the plug-shaped piece 3 is pressed into the base 1 from the bottom, thereby completing the assembly.

[0115] For example, such as Figures 1-14 As shown, at least one embodiment of the present invention also provides a motor 1000, which includes a rotor assembly 100 as described in any of the examples above, and a main shaft 200. The motor 1000 may be a stepper motor.

[0116] Based on this solution, this utility model can solve the technical problems of improving the structural stability of stepper motors and enhancing the efficiency of automated production. It should be noted that the specific implementation and technical effects of the motor 1000 in this embodiment can be found in the description of the rotor assembly 100 above; for clarity and brevity, they will not be repeated here. It should also be noted that other parts of the motor 1000 in this embodiment are not the focus of this utility model and will not be specifically shown or described herein.

[0117] It should be noted that the accompanying drawings of the embodiments of this utility model only relate to the structures involved in the embodiments of this utility model; other structures can be referred to with ordinary design. It should be understood that the above description is intended to illustrate and not limit. For example, the above embodiments (and / or aspects thereof) can be used in combination with each other. Furthermore, many modifications can be made to adapt specific situations or materials to the teachings of this utility model without departing from its scope. The functions or performance of the various elements or modules described herein are for illustrative purposes only and are by no means limiting, but merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those skilled in the art after reading the above description. Therefore, the scope of this utility model should be determined by reference to the appended claims and the full scope of their equivalents.

Claims

1. A rotor assembly (100) of an electric motor (1000), characterized in that, include: The base (1) includes a main sleeve (11) and an extension sleeve (12) extending from a first end (1A) of the main sleeve (11) along the axial direction (D1) of the main sleeve (11), the main sleeve (11) having a first end (1A) and a second end (1B) opposite each other in the axial direction (D1), and the extension sleeve (12) having a first shaft hole (121) through which the spindle (200) of the motor (1000) passes along the axial direction (D1). A magnetic ring (2) is sleeved on the outside of the main body sleeve (11) and fixedly connected to the main body sleeve (11); A plug (3) through which the main shaft (200) passes along the axial direction (D1) is fixed in the inner hole (14) of the main body sleeve (11), wherein the plug (3) comprises: a first part (31), a second part (32) and a third part (33) arranged sequentially from the second end (1B) along the axial direction (D1). Wherein, the second shaft hole (311) of the first part (31) is clearance-fitted with the main shaft (200), the third shaft hole (331) of the third part (33) is clearance-fitted with the main shaft (200), and the second part (32) is provided with a spring piece (4) for contacting the surface of the main shaft (200) that is inserted into the plug (3) to elastically fit with the main shaft (200).

2. The rotor assembly (100) as claimed in claim 1, characterized in that, The spring piece (4) and the plug-like member (3) are integrally formed.

3. The rotor assembly (100) as claimed in claim 1, characterized in that, The spring (4) extends along the axial direction (D1) and has a free end (4A) and a connecting end (4B) opposite each other in the axial direction (D1). The free end (4A) is closer to the center line (O1) of the second shaft hole (311) of the first part (31) than the connecting end (4B).

4. The rotor assembly (100) as claimed in claim 3, characterized in that, The connecting end (4B) is located in the second part (32) near the end of the first part (31), and the radial distance of the connecting end (4B) is equal to the inner diameter of the second shaft hole (311) of the first part (31).

5. The rotor assembly (100) as claimed in claim 4, characterized in that, The shrapnel (4) includes a plurality of shrapnel (401) arranged at intervals in the circumferential direction.

6. The rotor assembly (100) as claimed in claim 5, characterized in that, The plurality of bullet fragments (401) include a first bullet fragment (41) and a second bullet fragment (42) arranged radially opposite to each other along the plug (3).

7. The rotor assembly (100) as claimed in claim 6, characterized in that, The second part (32) forms a first cavity (32A) by perforating radially upward along the plug (3), the perforation forming two openings (321) that are radially opposite to each other in the plug (3).

8. The rotor assembly (100) as claimed in claim 7, characterized in that, The first bullet fragment (41) and the second bullet fragment (42) are disposed at the junction (501) of the first cavity (32A) and the second shaft hole (311) of the first part (31).

9. The rotor assembly (100) as claimed in claim 7, characterized in that, The cross-section of the opening (321) is square.

10. The rotor assembly (100) as claimed in claim 3, characterized in that, The spring piece (4) is inclined relative to the axis (D1), and the angle between the extension direction of the spring piece (4) and the axis (D1) is 5°~30°.

11. The rotor assembly (100) as claimed in claim 3, characterized in that, The end (301A) of the second shaft hole (311) of the first part (31) away from the second part (32) is provided with a trumpet-shaped chamfer, and the end (303A) of the third shaft hole (331) of the third part (33) near the second part (32) is provided with a double chamfer.

12. The rotor assembly (100) as claimed in claim 3, characterized in that, The outer end (302B) of the third part (33) on the side away from the second part (32) is chamfered.

13. The rotor assembly (100) as claimed in claim 3, characterized in that, The third part (33) has a tapered guide groove (332), which is located on the side of the third shaft hole (331) of the third part (33) away from the second part (32), and the tapered guide groove (332) is connected to the third shaft hole (331) of the third part (33) so that the main shaft (200) passes through along the axial direction (D1).

14. The rotor assembly (100) as claimed in claim 3, characterized in that, The ratio of the radial distance of the free end (4A) of the spring (4) in its free state to the outer diameter of the main shaft (200) is 0.95-0.

97.

15. The rotor assembly (100) as claimed in claim 7, characterized in that, The plug-like member (3) includes a base (31a) and a boss (31b). The boss (31b) includes a first segment (31d), a second part (32) and a third part (33) of the first part (31) arranged sequentially in the axial direction (D1). The base (31a) is the remaining part (31e) of the first part (31) excluding the first segment (31d). The inner hole (14) of the main sleeve (11) includes: a first hole (141) that corresponds to and cooperates with the base (31a) and a second hole (142) that corresponds to and cooperates with the boss (31b), wherein the inner diameter of the first hole (141) is larger than the inner diameter of the second hole (142); The inner diameter (C01) of the second hole (142) is smaller than the outer diameter (C02) of the boss (31b).

16. The rotor assembly (100) as claimed in claim 15, characterized in that, The length (D01) of the second hole (142) in the axial direction (D1) is greater than the length (d02) of the boss (31b) in the axial direction (D1), so that the inner hole (14) of the third part (33) and the main body sleeve (11) forms a first suspended area (T1), and the first cavity (32A) is a second suspended area (T2).

17. The rotor assembly (100) as claimed in claim 3, characterized in that, The free end (4A) of the spring (4) is provided with a chamfer (4A1).

18. The rotor assembly (100) as claimed in claim 1, characterized in that, The spring piece (4) extends radially along the plug-like member (3) and has an arc-shaped inner side; The radius (R1) of the arc at the end of the arc surface near the first part (31) along the axial direction (D1) is equal to the inner diameter (R2) of the second shaft hole (311) of the first part (31), and the radius (R3) of the arc at the end of the arc surface away from the first part (31) along the axial direction (D1) is smaller than the inner diameter (R2) of the second shaft hole (311) of the first part (31).

19. The rotor assembly (100) as claimed in claim 18, characterized in that, The second part (32) forms a first cavity (32A) by perforating radially upward along the plug (3); The spring piece (4) includes: at least one first arc-shaped spring piece (43) disposed on the first inner sidewall (3201) in the first cavity (32A), and at least one second arc-shaped spring piece (44) disposed on the second inner sidewall (3202) opposite to the first inner sidewall (3201) in the first cavity (32A), wherein the first arc-shaped spring piece (43) and / or the second arc-shaped spring piece (44) extend radially along the plug-like member (3) and have an inner arc surface; The first arc-shaped spring (43) and the second arc-shaped spring (44) are arranged opposite to each other so that the surfaces of the first arc-shaped spring (43) and the second arc-shaped spring (44) respectively contact the surfaces opposite to the main shaft (200).

20. A motor (1000), characterized in that, Including the rotor assembly (100) as described in any one of claims 1-19, the motor (1000) further includes the spindle (200), and the motor (1000) is a stepper motor.

Images