A voice coil motor

Abstract

The utility model relates to a kind of voice coil motor, including stator assembly, the stator assembly includes the shell with opening in top and the magnetic circuit component coaxially fixed in the shell, the magnetic circuit component has hollow portion through and through in axial direction;Mover component, the mover component includes bobbin and coil fixed in the outer side of bobbin, the mover component is housed in the shell, and located in the accommodation space formed between the magnetic circuit component and the inner wall of the shell;Guiding structure, coaxially housed in the hollow portion of the magnetic circuit component, the guiding structure has fixed end and sliding end, the fixed end is fixedly connected with the bottom of the shell, the sliding end is fixedly connected with the bobbin of the mover component. Through the above design, the dependence of traditional voice coil motor on external slide rail and load slide table is reduced, so as to reduce the number of parts and assembly difficulty, improve the module integration, with the characteristics of simple structure, easy to install.

Description

Technical Field

[0001] This utility model relates to the field of drive mechanism technology, specifically to a voice coil motor. Background Technology

[0002] A voice coil motor is a drive device that achieves linear motion or angular displacement based on the principle of electromagnetic induction. Due to its simple structure, fast response speed, and high control precision, it is widely used in optical focusing systems, precision positioning platforms, automation devices, and semiconductor equipment. Existing voice coil motors typically consist of components such as a coil, magnet, magnetic conductor, housing, linear guide rail, slider, and mounting base. The interaction between the coil and the magnetic field generates thrust, enabling the mover to achieve reciprocating linear motion under the constraint of the guide rail.

[0003] In existing technologies, to ensure the smoothness and accuracy of the mover during motion, most voice coil motors employ an external guide rail and slider guiding method. While this approach guarantees high motion accuracy, the overall structure is complex, with numerous parts and cumbersome assembly processes, leading to high manufacturing and assembly costs. Furthermore, since the guide rail and slider are typically separated from the motor body, the structural volume increases, and assembly coaxiality and guiding accuracy are easily affected by accumulated errors, limiting the miniaturization and modularization of the motor. On the other hand, traditional magnetic circuit components usually consist of magnets and magnetic guide blocks arranged in parallel or symmetrical arrangements. Their magnetic circuit sealing and flux utilization are low, resulting in problems such as flux leakage and uneven magnetic field distribution, thus affecting the stability of the motor's thrust output and energy efficiency. However, existing voice coil motors still suffer from problems such as numerous parts, complex structure, high cost, and cumbersome installation in terms of guiding structure, magnetic circuit design, and assembly methods. Therefore, it is necessary to research and improve the structure of such voice coil motors; to solve the above problems, the concept of this application is proposed. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of the prior art. This application provides a voice coil motor to solve the technical problems of the prior art in terms of structure and assembly method, which still have many parts, complex structure and cumbersome installation.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a voice coil motor, comprising: a stator assembly, the stator assembly including a housing with an opening at the top and a magnetic circuit component coaxially fixed within the housing, the magnetic circuit component having an axially penetrating hollow portion; a mover component, the mover component including a coil frame and a coil fixed to the outside of the coil frame, the mover component being housed within the housing and located within an accommodating space formed between the magnetic circuit component and the inner wall of the housing; and a guide structure coaxially housed within the hollow portion of the magnetic circuit component, the guide structure having a fixed end and a sliding end, the fixed end being fixedly connected to the bottom of the housing, and the sliding end being fixedly connected to the coil frame of the mover component. Through the above design, a high degree of structural integration is achieved, significantly reducing the number of independent components.

[0006] Preferably, the fixed end of the guide structure is provided with an external thread, and the bottom of the outer shell is provided with a threaded groove coaxial with the hollow part. The fixed end is threadedly connected to the threaded groove through the external thread. This achieves rapid and accurate positioning and firm fixation of the guide structure, simplifies the assembly process, reduces assembly difficulty, and ensures the coaxiality of the guide structure and the outer shell.

[0007] Preferably, the fixed end of the guide structure is a shaft-type structure, and the sliding end of the guide structure is a hollow bushing structure, with the length of the shaft-type structure being greater than that of the bushing structure. This solves the safety problem that, under overtravel or accidental impact conditions, the sliding end and fixed end of the guide structure may completely detach, leading to loss of guidance for the mover, motor jamming, or damage. It thus provides a mechanical hard limit, preventing complete detachment and improving the reliability and safety of the equipment.

[0008] Preferably, the bottom inner side of the outer casing is provided with an inwardly recessed annular positioning part, and the bottom of the magnetic circuit component is accommodated within the annular positioning part and fixed therewith. This achieves precise installation and fixation of the magnetic circuit component, enables rapid installation, and ensures the coaxiality of the magnetic circuit component with the outer casing and guide structure, thereby guaranteeing the symmetry and uniformity of the magnetic field distribution.

[0009] Preferably, a first gap is formed between the inner peripheral wall of the mover component and the outer peripheral wall of the magnetic circuit component, and a second gap is formed between the outer peripheral wall of the wire frame and the inner peripheral wall of the housing; the widths of the first gap and the second gap are equal. This provides a balanced suspension and guiding space for the mover component, effectively avoiding rigid contact friction with the stator assembly, and ensuring the smoothness and high precision of the axial movement of the mover.

[0010] Preferably, the magnetic circuit component includes a magnetically conductive block and a magnet, wherein the axial thickness of the magnet is greater than the axial thickness of the magnetically conductive block. By optimizing the ratio of magnetic material to magnetically conductive material, a stronger and more uniform magnetic field distribution can be established in a limited space.

[0011] Preferably, the axial thickness of the magnet is 1.2 to 3.5 times the axial thickness of the magnetic guide block. This ratio range significantly improves the linearity of the magnetic field and the accuracy of the thrust, resulting in more balanced force on the coil and smoother motor response.

[0012] Preferably, both ends of the coil frame are provided with radially extending outer edges, which, together with the coil frame, form an accommodating space for winding and limiting the coil. This effectively limits and protects the coil during winding, improving the reliability and durability of the product under long-term reciprocating motion.

[0013] Preferably, the side wall of the housing has at least one heat dissipation hole, which communicates with the accommodating space. By creating a heat dissipation hole communicating with the accommodating space, an air convection channel is established, which can dissipate the heat generated by the coil to the outside in a timely manner, effectively reducing the internal operating temperature and ensuring the continuous high-performance operation and lifespan of the motor.

[0014] Preferably, the wire frame is made of plastic, and at least one wear-resistant ring is embedded in the inner or outer peripheral wall of the wire frame. By using a plastic wire frame, which has the advantages of being lightweight and having low inertia, the embedded wear-resistant ring greatly improves the wear resistance life of the moving parts, reduces frictional resistance and wear debris, and further ensures the stability, accuracy and reliability of the motor during long-term operation.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: This voice coil motor includes a stator assembly comprising a housing with an opening at the top and a magnetic circuit component coaxially fixed within the housing, the magnetic circuit component having an axially penetrating hollow portion; a mover assembly comprising a coil frame and a coil fixed to the outside of the coil frame, the mover assembly being housed within the housing and located within an accommodating space formed between the magnetic circuit component and the inner wall of the housing; and a guide structure coaxially housed within the hollow portion of the magnetic circuit component, the guide structure having a fixed end and a sliding end, the fixed end being fixedly connected to the bottom of the housing, and the sliding end being fixedly connected to the coil frame of the mover assembly. This design reduces the reliance on external slide rails and load slides inherent in traditional voice coil motors, thereby reducing the number of components and assembly difficulty, improving module integration, and offering the advantages of simple structure and convenient installation.

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a top view of the structure of this utility model; Figure 3 This utility model Figure 2 A schematic diagram of the cross-sectional structure; Figure 4 This is an exploded structural diagram of the present invention; Figure 5 This is a three-dimensional structural schematic diagram of the present invention. Reference numerals: 1. Stator assembly; 11. Housing; 111. Opening; 112. Slot; 12. Magnetic circuit component; 121. Hollow part; 122. Magnetic guide block; 123. Magnet; 2. Mover component; 21. Wire frame; 211. Outer edge; 212. Spacing part; 213. Fixing part; 22. Coil; 3. Spacing; 4. Guide structure; 41. Shaft structure; 42. Bushing structure; 5. First gap; 6. Second gap. Detailed Implementation

[0018] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Detachable installation methods are varied, such as through plug-in and snap-fit ​​connections, or through bolt connections, etc.

[0019] The present invention will now be described in more detail with reference to specific embodiments. However, the implementation of the present invention is not limited thereto. The embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention. For process parameters or conditions not specifically specified, conventional techniques can be referred to.

[0020] Please see Figures 1-5As shown, the technical solution adopted in this specific embodiment is as follows: a voice coil motor is provided, including: a stator assembly 1, the stator assembly 1 including a housing 11 with an opening 111 at the top and a magnetic circuit component 12 coaxially fixed inside the housing 11, the magnetic circuit component 12 having an axially penetrating hollow portion 121; a mover component 2, the mover component 2 including a coil frame 21 and a coil 22 fixed to the outside of the coil frame 21, the mover component 2 being housed inside the housing 11 and located in the accommodating space formed between the magnetic circuit component 12 and the inner wall of the housing 11; and a guide structure 4, coaxially housed inside the hollow portion 121 of the magnetic circuit component 12, the guide structure 4 having a fixed end and a sliding end, the fixed end being fixedly connected to the bottom of the housing 11, and the sliding end being fixedly connected to the coil frame 21 of the mover component 2.

[0021] In this embodiment, the outer casing 11 can be a cylindrical metal structure with an opening 111 at its top for the moving component 2 to extend out. The magnetic circuit component 12 is coaxially fixed inside the outer casing 11, forming an axially penetrating hollow portion 121. The guide structure 4 passes through the hollow portion 121 and is arranged along the central axis of the outer casing 11 of the motor. The coil frame 21 of the moving component 2 is fixed inside the coil 22 and is fitted entirely within the accommodating space between the magnetic circuit component 12 and the outer casing 11. When current flows into the coil 22, the coil 22 generates axial thrust under the action of the radial magnetic field, causing the moving component 2 to reciprocate linearly along the axial direction of the guide structure 4. Through the above design, a high degree of integration of the voice coil motor is achieved. The magnetic circuit, the moving component 2, and the guide structure 4 are all arranged around the central axis, reducing the reliance on external guide rails or support components in traditional voice coil motors, thereby significantly reducing the number of parts and assembly complexity. It should be noted that the outer casing 11 can be made of aluminum alloy or high-strength engineering plastic to balance heat dissipation and lightweight. In addition, the magnetic circuit component 12 can be assembled in a multi-section modular manner to adapt to the design requirements of different thrust levels.

[0022] The fixed end of the guide structure 4 is provided with an external thread, and the bottom of the outer shell 11 is provided with a threaded groove 112 coaxial with the hollow part 121. The fixed end is threadedly connected to the threaded groove 112 through the external thread. In this embodiment, the fixed end of the guide structure 4 is a cylindrical structure with precision external threads machined on its outer circumference; the bottom of the outer shell 11 is provided with a coaxial threaded groove 112. During installation, the guide structure 4 can be directly screwed into the groove 112 at the bottom of the outer shell 11 for quick fixing. This threaded connection structure not only provides a strong mechanical connection force but also facilitates assembly, disassembly, and maintenance. Furthermore, the threaded connection enables precise positioning of the guide structure 4 and the outer shell 11, improving the coaxiality of the component assembly and avoiding eccentric errors caused by welding or bonding, thereby ensuring smooth sliding of the moving component 2 during operation. It should be noted that a positioning washer or a backstop structure can be added between the guide structure 4 and the outer shell 11 to prevent loosening caused by long-term vibration. In another alternative, the guide structure 4 can also be positioned by means of slots or pins to adapt to different structural layout requirements.

[0023] The fixed end of the guide structure 4 is a shaft-shaped structure 41, and the sliding end of the guide structure 4 is a hollow bushing structure 42. The length of the shaft-shaped structure 41 is greater than that of the bushing structure 42. Preferably, the shaft-shaped structure 41 is a ball spline shaft, and the bushing structure 42 is a ball spline shaft sleeve. In this embodiment, the shaft-shaped structure 41 of the guide structure 4 is fixedly connected to the bottom of the housing 11, and the bushing structure 42 mates with the center hole of the wire frame 21 of the moving component 2. By designing the length of the shaft-shaped structure 41 to be greater than that of the bushing structure 42, even under the extreme stroke of the moving component 2, the bushing structure 42 will not completely detach from the shaft-shaped structure 41. This structure provides a mechanical limiting function, preventing the moving component 2 from completely disengaging from the guide mechanism under over-travel or impact conditions, thereby avoiding jamming or structural damage and improving the safety and reliability of the system. It should be noted that the inner wall of the bushing structure 42 may be provided with a lubricating coating or a self-lubricating bushing to further reduce friction. In another alternative, an elastic limit ring can be set at the sliding end to achieve a flexible anti-detachment design.

[0024] The bottom inner side of the outer casing 11 is provided with an inwardly recessed annular positioning part. The bottom of the magnetic circuit component 12 is accommodated within the annular positioning part and fixed therewith. In this embodiment, the bottom of the outer casing 11 is machined with an annular groove as a positioning part. During assembly, the bottom of the magnetic circuit component 12 is directly embedded in the annular positioning part, forming an interference fit or a positioning fit, thereby achieving quick installation, positioning, and reliable fixation. This structure ensures that the magnetic circuit component 12 is stably positioned in both the radial and axial directions, preventing the magnetic circuit assembly from shifting, maintaining overall coaxiality and magnetic field symmetry, and improving the linearity and repeatability of the motor's thrust. It should be noted that an annular buffer pad or insulating pad can be added inside the annular positioning part to reduce the impact of assembly tolerances. In another embodiment, adhesive can be used to assist in fixation to improve stability under vibration.

[0025] A first gap 5 is formed between the inner peripheral wall of the mover component 2 and the outer peripheral wall of the magnetic circuit component 12, and a second gap 6 is formed between the outer peripheral wall of the wire frame 21 and the inner peripheral wall of the outer shell 11; the widths of the first gap 5 and the second gap 6 are equal. In this embodiment, the mover component 2 is precisely fitted in the radial direction to ensure that the two gaps are of equal width. Through processing control, the mover is positioned at the center of the magnetic circuit during movement. Through the above design, the mover component 2 can be subjected to symmetrical forces, reducing lateral friction caused by bias magnetism and ensuring the smoothness and accuracy of the mover's linear motion. It should be noted that, preferably, the gap width can be set between 0.1 and 0.3 mm according to the design thrust range. In another variation, the gap can be adjusted and controlled by the fine-tuning structure of the guide structure 4.

[0026] The magnetic circuit component 12 includes a magnetically conductive block 122 and a magnet 123, wherein the axial thickness of the magnet 123 is greater than the axial thickness of the magnetically conductive block 122. In this embodiment, the magnetic circuit component 12 is formed by stacking upper and lower magnetically conductive blocks 122 and magnets 123. The magnet 123 is thicker than the magnetically conductive block 122 in the axial direction, and this proportional relationship strengthens the magnetic flux concentration area. By optimizing the ratio of magnetic material to magnetically conductive material, a stronger and more uniform magnetic field distribution is established in a limited space. It should be noted that the magnet 123 can be made of neodymium iron boron material, and the magnetically conductive block 122 can be made of pure iron or a soft magnetic alloy. Another alternative is to add magnetic flux guiding grooves to the edge of the magnetically conductive block 122 to further homogenize the magnetic field.

[0027] The axial thickness of magnet 123 is 1.2 to 3.5 times the axial thickness of magnetic block 122. This ratio range significantly improves magnetic field linearity and thrust accuracy, resulting in more balanced force on coil 22 and smoother motor response. It should be noted that, in different applications, the thickness of magnet 123 can be adjusted within the above range according to thrust requirements and volume constraints to balance performance and cost.

[0028] Both ends of the wire frame 21 are provided with radially extending outer edges 211, which, together with the wire frame 21, form an accommodating space for winding and limiting the coil 22. In this embodiment, the wire frame 21 is generally cylindrical, with the outer edges 211 at both ends protruding radially to form limiting edges for the coil 22. The coil 22 is wound in the annular space between the two outer edges 211, preventing axial displacement or detachment of the coil 22. This structure effectively protects the winding layer of the coil 22, preventing the coil 22 from loosening or wearing, and improving the stability and durability of the product under high-frequency reciprocating motion. It should be noted that the outer edges 211 can be provided with rounded corners to reduce stress concentration in the coil 22 coating layer. In another embodiment, an insulating resin layer can be coated on the inner side of the outer edges 211 to enhance heat resistance.

[0029] At least one heat dissipation hole is provided on the side wall of the outer casing 11, and the heat dissipation hole communicates with the accommodating space. In this embodiment, the heat dissipation hole directly connects to the interior of the accommodating space. When the mover reciprocates, airflow is generated, which carries away the operating heat of the coil 22. However, by forming a natural convection channel, the internal temperature rise of the motor is effectively reduced, improving long-term operational reliability and stability. It should be noted that a dustproof screen or a microporous metal filter can be installed at the heat dissipation hole to prevent external particles from entering the internal magnetic circuit area. In another embodiment, the shape of the heat dissipation hole can be a circular hole, an elongated hole, or a mesh hole structure.

[0030] The wire frame 21 is made of plastic, and at least one wear-resistant ring is embedded in its inner or outer peripheral wall. In this embodiment, the wire frame 21 can be made of high-strength engineering plastic, such as PPS or PA66, and injection molded, with a metal or PTFE wear-resistant ring on its inner peripheral wall. This wear-resistant ring can form a low-friction sliding pair with the guide structure 4. The plastic wire frame 21 possesses lightweight and low-inertia characteristics, while the wear-resistant ring provides long-life sliding support, significantly reducing friction and wear, and ensuring the smoothness and positioning accuracy of the mover's movement. It should be noted that the wear-resistant ring can be fixed by embedding, press fitting, or ultrasonic welding; alternatively, a composite material integral molding scheme can be used to reduce the number of parts.

[0031] In summary, the voice coil motor of this invention fully embodies the concepts of high integration, fewer parts, and simple assembly in its overall structural design. The stator assembly 1, the mover component 2, and the guide structure 4 are all coaxially arranged along the central axis, achieving a compact structure and mechanical symmetry through precise assembly relationships. The guide structure 4 is directly installed in the threaded slot 112 at the bottom of the housing 11. The magnetic circuit component 12 is precisely positioned through the annular positioning part, and the mover component 2 is suspended in the magnetic field through a preset accommodating space and gap, eliminating the need for additional guide rails or sliding supports, thereby effectively reducing redundant parts in traditional voice coil motors.

[0032] During assembly, the magnetic circuit component 12 is simply inserted into the annular positioning part of the housing 11 and fixed in sequence. The fixed end of the guide structure 4 is then threaded to the threaded groove 112 at the bottom of the housing 11. Finally, the moving component 2 is inserted into the receiving space along the guide structure 4 and fixed to the sliding end of the guide structure 4 by a fastener. This completes the main assembly. This process eliminates the need for complex coaxial alignment or precision adjustments, significantly improving assembly efficiency and consistency. During operation, the moving component 2 reciprocates smoothly along the guide structure 4 under current drive. The first gap 5 and the second gap 6 provide symmetrical magnetic field space and mechanical buffering, ensuring the balance and low friction characteristics of the motion. The axial hard limit design of the guide structure 4 prevents the moving component from dislodging under overtravel or impact, further enhancing the safety and reliability of the system.

[0033] In summary, this voice coil motor, through its integrated structural design, significantly reduces the number of parts and simplifies the installation process while ensuring high thrust output and precise guidance. This results in a more compact overall structure, smoother operation, and excellent assembly precision and long-term operational stability.

[0034] The foregoing, in conjunction with the embodiments and accompanying drawings, has clearly and completely described the concept, specific structure, and technical effects of this utility model, so as to fully understand the purpose, features, and effects of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are all within the protection scope of this utility model. Furthermore, all connections / linkages mentioned herein do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The specific description of the utility model in the above embodiments is only used to further illustrate this utility model and should not be construed as limiting the protection scope of this utility model. Any non-essential improvements and adjustments made to this utility model by those skilled in the art based on the above description fall within the protection scope of this utility model.

Claims

1. A voice coil motor, characterized in that, include: A stator assembly, comprising a housing with an opening at the top and a magnetic circuit component coaxially fixed within the housing, the magnetic circuit component having an axially penetrating hollow portion; A moving component, the moving component including a wire frame and a coil fixed to the outside of the wire frame, the moving component being housed within the housing and located within the accommodating space formed between the magnetic circuit component and the inner wall of the housing; A guide structure is coaxially housed within the hollow portion of the magnetic circuit component. The guide structure has a fixed end and a sliding end. The fixed end is fixedly connected to the bottom of the outer shell, and the sliding end is fixedly connected to the wire frame of the moving component.

2. The voice coil motor according to claim 1, characterized in that, The fixed end of the guide structure is provided with an external thread, and the bottom of the outer shell is provided with a threaded groove coaxial with the hollow part. The fixed end is threadedly connected to the threaded groove through the external thread.

3. The voice coil motor according to claim 1, characterized in that, The fixed end of the guide structure is a shaft-shaped structure, and the sliding end of the guide structure is a hollow bushing structure. The length of the shaft-shaped structure is greater than that of the bushing structure.

4. The voice coil motor according to claim 1, characterized in that, The bottom inner side of the outer shell is provided with an inwardly recessed annular positioning part, and the bottom of the magnetic circuit component is accommodated in the annular positioning part and fixed therewith.

5. The voice coil motor according to claim 1, characterized in that, A first gap is formed between the inner peripheral wall of the moving component and the outer peripheral wall of the magnetic circuit component, and a second gap is formed between the outer peripheral wall of the wire frame and the inner peripheral wall of the outer shell; the widths of the first gap and the second gap are equal.

6. The voice coil motor according to claim 1, characterized in that, The magnetic circuit component includes a magnetically conductive block and a magnet, wherein the axial thickness of the magnet is greater than the axial thickness of the magnetically conductive block.

7. The voice coil motor according to claim 6, characterized in that, The axial thickness of the magnet is 1.2 to 3.5 times the axial thickness of the magnetic block.

8. The voice coil motor according to claim 1, characterized in that, Both ends of the coil frame are provided with radially extending outer edges, which together with the coil frame form an accommodating space for winding and limiting the coil.

9. The voice coil motor according to any one of claims 1-8, characterized in that, The side wall of the outer casing has at least one heat dissipation hole, which is in communication with the accommodating space.

10. The voice coil motor according to any one of claims 1-8, characterized in that, The wire frame is made of plastic, and at least one wear-resistant ring is embedded in the inner or outer peripheral wall of the wire frame.

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