Polar plate structure of stepping motor casing

Abstract

The utility model discloses a stepping motor casing pole plate structure, which comprises a pair of pole plates and a pair of casings, the two casings form a motor casing, the two pole plates are arranged in the two casings, bases of the two pole plates are overlapped and fixed together and are arranged at the center of the motor casing, and the two pole plates are arranged in the motor casing. A circle of machine shell teeth vertically extending towards the center of the motor shell is fixed to each machine shell, pole plate teeth matched with the machine shell teeth are fixed to the two pole plates, the pole plate teeth and the machine shell teeth are each in a multi-section line tooth shape, each multi-section line tooth shape comprises a tooth root, a tooth face and a tooth top, each tooth face is in an arc line shape protruding outwards from the middle, and each tooth top is in an arc line shape protruding outwards from the middle. The arc line is tangent to the linear sections, the top of the tooth surface is connected with the tooth top through a tooth surface fillet, and the bottom of the tooth surface is connected with the tooth root through a tooth surface draft angle. According to the utility model, through the smooth transition of the multi-section line tooth form and the synchronous design of the pole plate teeth and the casing teeth, the static cogging torque and the operation vibration are obviously reduced, and the requirement of a mute scene is met.

Description

Technical Field

[0001] This utility model relates to a stepper motor housing electrode plate structure. Background Technology

[0002] Traditional stepper motors typically use an equal-segment design for the housing and electrode plates, with triangular or trapezoidal tooth profiles. This design presents the following problems:

[0003] 1. Large static cogging torque: Due to the sharp or symmetrical tooth profile and uneven magnetic field distribution, the cogging torque is significant when the motor is stationary, which affects the positioning accuracy.

[0004] 2. Operational vibration and noise: Traditional tooth profiles are prone to periodic vibration during operation, especially in quiet scenarios where they may resonate with other components, reducing system reliability.

[0005] In existing technologies, although some solutions improve torque by optimizing tooth profile, they are mostly limited to local modifications (such as chamfering and sharpening) and fail to achieve fundamental improvement through overall tooth profile reconstruction. Utility Model Content

[0006] To address the aforementioned problems, this utility model provides a stepper motor housing electrode plate structure, which effectively solves the problems pointed out in the background art.

[0007] The technical solution adopted in this utility model is:

[0008] A stepper motor housing electrode plate structure includes a pair of electrode plates and a pair of housings. The two housings form a motor housing. The two electrode plates are disposed within the two housings. The bases of the two electrode plates overlap and are fixed together and disposed at the center of the motor housing. Each housing is fixed with a ring of housing teeth extending perpendicularly toward the center of the motor housing. The two electrode plates are fixed with electrode plate teeth that match the housing teeth. The tooth profile of both the electrode plate teeth and the housing teeth is a multi-segment tooth profile. The multi-segment tooth profile includes a tooth root, a tooth surface, and a tooth tip. The shape of the tooth surface consists of an arc protruding outward from the center and straight line segments connecting the two ends of the arc. The arc and the straight line segments are tangent. The top of the tooth surface is connected to the tooth tip through a tooth surface rounded corner, and the bottom is connected to the tooth root through a tooth surface draft angle.

[0009] Preferably, the tooth root width of the multi-segment tooth profile is 1.12 to 1.18 times the width of the single-stage air gap magnetic field. The width of the single-stage air gap magnetic field = air gap circumference / number of magnetic poles. The air gap circumference refers to the circumference at the tooth root.

[0010] Preferably, the draft angle of the tooth surface is . .

[0011] Preferably, the tooth height of the multi-segment tooth profile is 0.4 to 0.42 times the air gap diameter.

[0012] Preferably, the arc of the tooth surface is a circular arc with the maximum outer diameter that is tangent to the straight segment of the tooth surface and connects to the tooth tip.

[0013] Preferably, the top of the multi-segment tooth profile is tangent to the tooth surface with the minimum manufacturable fillet, that is, the tooth surface fillet is the minimum manufacturable fillet.

[0014] This invention significantly reduces static cogging torque and operating vibration through the smooth transition of multi-segment tooth profiles and the synchronous design of electrode plate teeth and housing teeth, thus meeting the requirements of quiet operation scenarios.

[0015] The innovative points of this utility model are:

[0016] 1. Multi-segment tooth profile design:

[0017] Traditional stepper motors often have triangular or trapezoidal tooth profiles, resulting in uneven magnetic field distribution, which can easily lead to cogging torque and vibration noise. This technical solution adopts a multi-segment tooth profile, which connects the tooth root, tooth surface and tooth tip with a smooth transition curve to optimize the magnetic field distribution.

[0018] The tooth surface bulges outward in the middle, and the tooth tip is tangentially connected to the tooth surface through the rounded corners of the tooth surface, ensuring a natural transition of the magnetic field and reducing local magnetic field concentration;

[0019] The tooth height is designed to be 0.4 to 0.42 times the air gap diameter, and the tooth width is 1.12 to 1.18 times the width of a single-stage air gap magnetic field. The magnetic field uniformity is further improved through the optimization of geometric parameters.

[0020] 2. Synchronous design of electrode plate teeth and housing teeth:

[0021] The pole plate teeth rotate synchronously with the housing teeth by a step angle, so that the stator and rotor teeth always maintain magnetic circuit symmetry during the movement, avoiding step torque changes.

[0022] The beneficial effects of this utility model are:

[0023] 1. Significantly reduces static cogging torque:

[0024] Multi-segment tooth profile makes the magnetic field distribution more uniform, reduces static cogging torque by more than 40%, and improves the positioning accuracy and stability of the motor.

[0025] Simulation data shows that torque ripple is reduced by 15% to 42% compared to traditional triangular or trapezoidal tooth profiles;

[0026] 2. Reduce operating vibration and noise:

[0027] The smooth tooth design and synchronous rotation mechanism effectively suppress periodic vibrations, reducing the vibration amplitude by 30% to 50%.

[0028] The measured noise reduction is 10dB(A), making it especially suitable for quiet environments such as medical equipment and precision instruments.

[0029] 3. Compatibility and Usability:

[0030] The tooth profile design is compatible with existing motor manufacturing processes (such as deep drawing of cold-rolled sheet), eliminating the need for complex processing equipment and reducing costs;

[0031] It is suitable for miniature stepper motors with an outer diameter of 15~21mm and 5~7 teeth, thus expanding the application scenarios.

[0032] This invention optimizes both the magnetic field distribution and mechanical structure through multi-segment tooth profile reconstruction, completely solving the problems of high cogging torque and high vibration noise caused by tooth profile design defects in traditional stepper motors. Its innovation lies in the overall magnetic field optimization of the tooth profile, rather than local repair. The technical effect is significant and has good prospects for industrial application. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of this utility model;

[0034] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0035] Figure 3 The simulated dynamic tooth cogging torque diagram for the triangular tooth profile;

[0036] Figure 4 The simulated dynamic tooth cogging torque diagram for the trapezoidal tooth profile;

[0037] Figure 5 This is a simulated dynamic tooth cogging torque diagram of the multi-segment tooth profile of this utility model. Detailed Implementation

[0038] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0039] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0040] Furthermore, in the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0042] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0043] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0044] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0045] like Figure 1-2As shown, a stepper motor housing electrode plate structure includes a pair of electrode plates 1 and a pair of housings 2. The two housings 2 form the motor housing. The two electrode plates 1 are disposed inside the two housings 2. The bases of the two electrode plates 1 are overlapped and fixed together and disposed at the center of the motor housing. Each of the two housings 2 is fixed with a ring of housing teeth 21 extending vertically toward the center of the motor housing. The two electrode plates 1 are fixed with electrode plate teeth 11 that match the housing teeth 21. The tooth shape of the electrode plate teeth 11 and the housing teeth 21 are both multi-segment tooth shapes. The multi-segment tooth shape includes a tooth root 31, a tooth surface 32 and a tooth tip 33. The shape of the tooth surface 32 is composed of an arc line protruding outward from the middle and straight line segments connecting the two ends of the arc line. The arc line and the straight line segments are tangent. The top of the tooth surface 32 is connected to the tooth tip 33 through a tooth surface rounded corner, and the bottom is connected to the tooth root 31 through a tooth surface draft angle.

[0046] Furthermore, the electrode teeth 11 on the two electrode plates 1 are asymmetrically designed, and the housing teeth 21 on the two housings 2 are asymmetrically designed. The specific design scheme is as follows: the electrode teeth 11 are pre-rotated relative to the housing teeth 21 by a step angle, such as 12.85°, so that the stator and rotor teeth always maintain a smooth magnetic circuit during the movement; after rotation, the gap distribution between the electrode teeth and the housing teeth is more uniform, avoiding sudden changes in local magnetic reluctance, thereby suppressing torque fluctuations.

[0047] The tooth root width of the multi-segment tooth profile is 1.12 to 1.18 times the width of the single-stage air gap magnetic field. The width of the single-stage air gap magnetic field = air gap circumference / number of magnetic poles. The air gap circumference refers to the circumference at the tooth root. The draft angle of the tooth surface is... .

[0048] The tooth height of the multi-segment tooth profile is 0.4 to 0.42 times the air gap diameter.

[0049] The arc of the tooth surface 32 is a circular arc with the maximum outer diameter that is tangent to the straight segment of the tooth surface 32 and connects to the tooth tip 33.

[0050] The top of the multi-segment tooth profile is tangent to the tooth surface 32 with a minimum manufacturable radius.

[0051] To ensure a uniform magnetic field distribution on tooth surface 32 and reduce torque fluctuations, the control points of tooth surface 32 can be precisely designed: the control points of tooth surface 32 are optimized based on magnetic field simulation (such as Ansys Maxwell) to ensure that the tooth profile design is highly matched with the magnetic field distribution.

[0052] Take a 17mm diameter miniature stepper motor as an example:

[0053] The machine housing and electrode plates are formed by deep drawing of cold-rolled steel sheet, and the tooth shape is designed according to the optimized multi-segment line design, with 7 teeth.

[0054] Test results: Under the same driving conditions, compared with the traditional motor, the cogging torque decreased by 40% and the noise decreased by 10dB(A).

[0055] Comparative experiment:

[0056] Figure 3 Simulate dynamic cogging torque for triangular tooth profile;

[0057] Figure 4 Simulate dynamic cogging torque for trapezoidal tooth profile;

[0058] Figure 5 This utility model provides a simulation of dynamic tooth cogging torque using a multi-segment tooth profile.

[0059] according to Figure 3-5 As can be seen, Ansys Maxwell simulations show that torque ripple is reduced by 15-42%.

[0060] Meanwhile, the measured data shows that, under 12V / 120mA drive, compared with triangular tooth profile and trapezoidal tooth profile, the effective value of vibration velocity of multi-segment tooth profile decreased from 1.2mm / s to 0.7mm / s.

[0061] The core of this invention lies in optimizing the magnetic field distribution and mechanical structure through a multi-segment tooth profile design and a synchronous rotation mechanism between the electrode teeth and the housing teeth, thereby significantly reducing static cogging torque and operating vibration noise. Its working principle can be divided into the following parts:

[0062] 1. Magnetic field optimization for multi-segment tooth profiles:

[0063] Problems with traditional tooth profiles: Traditional stepper motors use triangular or trapezoidal tooth profiles with sharp or symmetrical tooth surfaces, which leads to uneven distribution of the magnetic field at the tooth tip and root, resulting in localized magnetic flux density concentration. This unevenness generates a large static cogging torque and causes periodic vibration and noise during operation.

[0064] Solution for multi-segment tooth profiles:

[0065] Smoothly transitioning magnetic field distribution: Multi-segment tooth profile passes through a tooth surface that convexes outward from the center (see...) Figure 1-2 The tooth surface 32) achieves a smooth transition of the magnetic field. The tooth surface uses multi-segment lines to connect the tooth root and tooth tip, avoiding the sharp turns of the traditional tooth shape and making the magnetic field lines more evenly distributed.

[0066] Tooth surface rounding optimization: The tooth tip is tangentially connected to the tooth surface through the tooth surface rounding. This design ensures a natural transition of the magnetic field at the tooth tip and reduces abrupt changes in magnetic flux.

[0067] Geometric parameter matching: the tooth height is 0.4 to 0.42 times the air gap diameter; the tooth width is 1.12 to 1.18 times the width of a single-stage air gap magnetic field (single-stage width = tooth root circumference / number of magnetic poles), to ensure magnetic field coverage between adjacent teeth and reduce magnetic leakage;

[0068] Simulation verification: Magnetic field simulation using Ansys Maxwell ( Figure 3-5 As can be seen, the torque fluctuation of the multi-segment tooth profile is reduced by 15% to 42% compared with the traditional tooth profile, and the static tooth cogging torque is reduced by more than 40%.

[0069] 2. Synchronous design of electrode plate teeth and housing teeth:

[0070] The gap distribution between the electrode plate teeth and the housing teeth is more uniform, avoiding sudden changes in local magnetic reluctance and thus suppressing torque fluctuations;

[0071] Dynamic performance improvement: Actual test data shows that the synchronous design reduces the effective value of vibration velocity from 1.2 mm / s to 0.7 mm / s and the noise is reduced by 10 dB(A) (e.g., from 50 dB to 40 dB).

[0072] Finally, it should be noted that the above examples are merely specific embodiments of this utility model. Obviously, this utility model is not limited to the above embodiments and can have many variations. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this utility model should be considered within the protection scope of this utility model.

Claims

1. A stepper motor housing electrode plate structure, characterized in that, The device includes a pair of electrode plates (1) and a pair of housings (2). The two housings (2) form a motor housing. The two electrode plates (1) are disposed inside the two housings (2). The bases of the two electrode plates (1) are overlapped and fixed together and disposed at the center of the motor housing. Both housings (2) are fixed with a ring of housing teeth (21) extending vertically toward the center of the motor housing. The two electrode plates (1) are fixed with electrode plate teeth (11) that match the housing teeth (21). The tooth shape of the electrode plate teeth (11) and the housing teeth (21) are both multi-segment tooth shapes. The multi-segment tooth shape includes a tooth root (31), a tooth surface (32) and a tooth tip (33). The shape of the tooth surface (32) is composed of an arc line that bulges outward from the middle and a straight line segment connecting the two ends of the arc line. The arc line is tangent to the straight line segment. The top of the tooth surface (32) is connected to the tooth tip (33) through a tooth surface rounded corner, and the bottom is connected to the tooth root (31) through a tooth surface draft angle.

2. The stepper motor housing electrode plate structure according to claim 1, characterized in that, The tooth root width of the multi-segment linear tooth profile is 1.12 to 1.18 times the width of the single-stage air gap magnetic field.

3. The stepper motor housing electrode plate structure according to claim 1, characterized in that, The angle of the tooth surface draft angle is: .

4. The stepper motor housing electrode plate structure according to claim 1, characterized in that, The tooth height of the multi-segment tooth profile is 0.4 to 0.42 times the air gap diameter.

5. The stepper motor housing electrode plate structure according to claim 1, characterized in that, The arc of the tooth surface (32) is the maximum outer diameter arc that is tangent to the straight segment of the tooth surface (32) and connects to the tooth tip (33).

6. The stepper motor housing electrode plate structure according to claim 1, characterized in that, The top of the multi-segment tooth profile is tangent to the tooth surface (32) with the minimum manufacturable fillet.

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