A Z-axis zoom component of a VCM motor

Abstract

The present invention discloses a Z-axis zoom component of a VCM motor, which is arranged outside a lens module and can be controlled by electromagnetics to make the lens module move in a directional manner to change the focal length, including a bracket and an upper spring sheet and a lower spring sheet arranged on both sides of the bracket; a carrier that can move linearly in the bracket is arranged in the bracket, the carrier is connected to the upper spring sheet and the lower spring sheet, and a restoring force is provided through the upper spring sheet and the lower spring sheet; a coil is sleeved on the carrier, a magnet that forms a magnetic field is arranged on the bracket, and the carrier is controlled to move in the bracket by energizing the coil; the upper spring sheet includes two identical groups of elastic components arranged on the same plane, the elastic component includes an outer spring sheet fixed on the bracket and an inner spring sheet arranged on the carrier; the outer spring sheet and the inner spring sheet are connected by at least two strings and provide elastic restoring force. The present invention has good stability by optimizing the internal structure design, and has a small volume and a relatively compact internal structure.

Description

Technical Field

[0001] The invention belongs to the technical field of electric control equipment, and in particular relates to a Z-axis zoom component of a VCM motor. Background Art

[0002] Voice coil motors are commonly used zoom mechanisms in small or micro camera modules. With the development of science and technology, mobile Internet technology is constantly updated, and many electronic devices are constantly miniaturized and refined. Because the integration of mobile terminal devices is getting higher and higher, it is necessary to retain the original functions of large components and shrink them so that multiple functions can be integrated into the terminal devices. For example, in order to complete the two basic functions of taking pictures and shooting videos, digital cameras at least need sensors that can convert the light entering the device into digital signals for processing and transmission, lens modules that can accurately let in light, and components that can move the lens modules for automatic focusing. In order to adapt to the trend of miniaturization technology, while being able to focus accurately and have high focusing efficiency, many of the original mechanical motors cannot adapt to existing mobile terminal devices.

[0003] Because the voice coil motor is a non-commutated power device, its positioning accuracy depends entirely on the feedback and control system, and has nothing to do with the voice coil motor itself. With the use of appropriate positioning feedback and sensing devices, its positioning accuracy can easily reach 10nm. Whether it is linear or swinging, their basic principles are the same. When a conductor with current passes through a magnetic field, it will generate a force perpendicular to the magnetic field lines. The magnitude of this force depends on the length of the conductor passing through the field, the magnetic field and the strength of the current. The magnitude of the thrust generated by the voice coil motor depends on the design structure and the current intensity. The relationship between the current and the generated force is reflected as force sensitivity in linear voice coil motors and torque sensitivity in rotary voice coil motors. The voice coil motor is a simple device that converts current into mechanical force, so its positioning and force control are achieved through position feedback devices and controllers. Its accuracy is determined by the controller and has nothing to do with the voice coil motor itself.

[0004] The existing voice coil motor includes a housing, a front gasket, an upper spring sheet, a bracket, a carrier, a coil, a lower spring sheet, a rear gasket and a base from top to bottom, wherein the coil is arranged on the carrier, and a permanent magnet for generating a fixed magnetic field is arranged on the bracket or the base. Because the upper spring sheet and the lower spring sheet are used to limit the carrier to move in the bracket for zooming, the existing upper spring sheet, carrier and bracket structure often moves too much and frequently, and the elastic bending part of the upper spring sheet is prone to fatigue fracture. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a Z-axis zoom assembly of a VCM motor.

[0006] The technical solution adopted by the present invention is:

[0007] A Z-axis zoom assembly of a VCM motor is arranged outside a lens module and uses electromagnetic control to make the lens module move in a directional manner to change the focal length, comprising a bracket and an upper spring sheet and a lower spring sheet arranged on both sides of the bracket;

[0008] The bracket is provided with a carrier which can move linearly in the bracket, and the carrier is connected with the upper spring sheet and the lower spring sheet and provides a restoring force through the upper spring sheet and the lower spring sheet;

[0009] The carrier is sleeved with a coil, and the bracket is provided with a magnet for forming a magnetic field, and the carrier is controlled to move in the Z-axis direction in the bracket by energizing the coil;

[0010] The upper spring sheet includes two identical groups of elastic components arranged on the same plane, and the elastic components include an outer elastic sheet fixed on the bracket and an inner elastic sheet arranged on the carrier;

[0011] The outer spring piece and the inner spring piece are connected by a plurality of strings and provide elastic restoring force.

[0012] The voice coil motor structure is applied to the camera to provide the effect of autofocus, which not only has high electromagnetic control accuracy, but also has high focusing efficiency due to its small size. In order to achieve the above basic functions, the camera of the existing mobile terminal device includes a sensor, a lens module and a voice coil motor, and the lens module is arranged in the voice coil motor. The Hall magnet fixed on the voice coil motor senses the moving position, and the action mechanism of the voice coil motor drives the directional displacement compared to the fixed sensor surface, thereby achieving the effect of adjusting the focal length.

[0013] The present invention is applied to control the axial movement of the lens module in the voice coil motor. Since the lens module is a moving part relative to the sensor, it is connected by two structures that can move relatively, namely the bracket and the carrier. The carrier is used to carry the lens module, and the bracket is fixedly connected to the sensor. The carrier can perform linear reciprocating motion in the bracket, and is limited by the inner wall plane of the shell top surface and the four blades of the carrier.

[0014] That is to say, the upper spring sheet and the lower spring sheet are connected to the carrier at the same time, and in the absence of external force, the gravity of the entire carrier and the pulling force of the two spring sheets form a static balance, and the carrier is in a suspended state relative to the bracket. In order to accurately move the carrier, a magnet is provided on the bracket to form a magnetic field, and a coil fixedly connected to the carrier is provided on the carrier to form an electromagnetic induction force, so that the movement of the carrier is controlled by controlling the magnitude and direction of the current input to the coil.

[0015] Because the movement of the carrier is precisely positioned through the joint action of two spring sheets and the coil, and in the voice coil motor with OIS anti-shake function, the lower spring sheet needs to provide a restoring force on the X / Y plane, then the upper spring sheet needs to have a good rebound effect, and at the same time have good stability and structural strength. In order to increase the service life and reduce the difficulty of processing and manufacturing, the present invention divides the upper spring sheet into two identical parts. The carrier and the bracket are both annular structures, and the upper spring sheet is divided into two identical structural rings and is symmetrical about the center point of the bracket during installation. In order to provide better rebound performance, an inner and outer two-layer connection structure is set, and multiple strings are used for connection.

[0016] Furthermore, a control line and a power supply line are provided inside the bracket, and a contact A connected to the control line and a contact B connected to the power supply line are provided on the surface of one side of the upper spring sheet, and the contact A and the contact B are provided at the gap between the two elastic components;

[0017] The outer spring piece of the elastic component is in contact with the contact A and the contact B, and the inner spring piece of the elastic component is connected to the contact C arranged on the carrier for connecting the coil.

[0018] Furthermore, a positioning permanent magnet is provided on the carrier for facilitating positioning, and a Hall sensor for providing information feedback to the positioning permanent magnet is provided on the bracket.

[0019] Furthermore, the bracket is provided with a groove to facilitate the string to swing up and down.

[0020] Furthermore, the bracket is provided with a positioning column for fixing the upper spring sheet.

[0021] Furthermore, a threaded hole or a non-threaded hole for fixing the lens module is provided on the inner side of the carrier.

[0022] Furthermore, a guide blade is provided on the outer side of the carrier, and a plurality of limit grooves cooperating with the guide blade to realize linear motion are provided on the inner side of the bracket.

[0023] Furthermore, the control wiring and the power supply wiring in the bracket are both formed by injection molding a conductive material or a metal stamping part with a conductive function in a circuit design together with the bracket substrate.

[0024] Furthermore, the bracket is provided with at least four mounting grooves on the side where the lower spring sheet is provided, and the magnets are nested in the mounting grooves.

[0025] Furthermore, the inner surface of the mounting groove is provided with a plurality of strip-shaped protrusions for providing glue storage grooves for storing glue for the magnet.

[0026] The beneficial effects of the present invention are:

[0027] (1) The present invention improves the stability of the entire limit elastic mechanism by configuring the upper spring sheet to be two parts, and designing each elastic component to be an inner and an outer part, which are connected by a plurality of strings. At the same time, by increasing the length of the string, fatigue fracture of the material due to a large bending amplitude caused by an excessively short force arm is avoided.

[0028] (2) The present invention forms an integrated circuit structure by injection molding a conductive material circuit in the frame or by stamping the circuit, thereby avoiding external wiring or using a PCB soft board for conductive control, and using the inner wall plane of the shell top surface and the four blades of the carrier to achieve a limiting effect. At the same time, the coil is conductive through its metal material, thereby reducing the number of assembly stations and assembly personnel, and avoiding the situation where its stability is reduced due to a large number of wiring or components. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the assembly of the entire voice coil motor of the present invention;

[0030] Figure 2 It is a schematic diagram of the disassembled structure of the entire zoom assembly of the present invention;

[0031] Figure 3 The present invention Figure 2 An enlarged schematic diagram of

[0032] Figure 4 It is a schematic diagram of the assembly of the entire zoom assembly in the present invention;

[0033] Figure 5 It is a schematic diagram of the split structure of the bracket of the present invention and the circuit buried in the bracket;

[0034] Figure 6 It is a schematic diagram of the bottom structure of the entire zoom assembly of the present invention when assembled, in which the arrangement position of the magnet can be seen;

[0035] Figure 7 It is a schematic structural diagram of the entire support of the present invention.

[0036] In the figure: 1- bracket, 2- upper spring sheet, 2.1- outer spring sheet, 2.2- inner spring sheet, 2.3- string, 3- lower spring sheet, 4- carrier, 5- coil, 6- guide blade, 7- magnet, 8- Hall magnet. DETAILED DESCRIPTION

[0037] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments.

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0040] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0041] In the description of this application, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, if the terms "first", "second", etc. appear in the description of this application, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] In addition, if the terms "horizontal" or "vertical" appear in the description of this application, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0043] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] Embodiment 1:

[0045] First, this embodiment is applied in a voice coil motor to control the axial movement of a lens module. Since the lens module is a movable part relative to the sensor, it is connected by two structures that can move relatively, namely, the bracket 1 and the carrier 4.

[0046] The carrier 4 is used to carry the lens module, and the bracket 1 is fixedly connected to the sensor. A Hall magnet 8 for sensing position is fixed on the carrier 4. The coil 5 is energized to generate magnetic field induction with multiple magnets 7 in the bracket 1, and can perform linear reciprocating motion in the bracket 1. The positioning is limited by the magnets 7 arranged at the four corners of the bracket 1, the inner wall plane of the top surface of the entire voice coil motor housing, and the four guide blades 6 of the carrier 4.

[0047] This embodiment discloses a Z-axis zoom assembly of a VCM motor, comprising a bracket 1 and an upper spring sheet 2 and a lower spring sheet 3 arranged on both sides of the bracket 1; a carrier 4 is arranged in the bracket 1 and can move linearly in the bracket 1, and the carrier 4 is connected to the upper spring sheet 2 and the lower spring sheet 3 and provides a restoring force through the upper spring sheet 2 and the lower spring sheet 3. In the absence of a driving force generated when the coil is energized, the gravity exerted on the entire carrier 4 forms a static balance with the pulling force of the two spring sheets, and the carrier 4 is in a suspended state relative to the bracket 1. In order to accurately move the carrier 4, a magnetic field is formed by providing a magnet 7 on the bracket 1, and an electromagnetic induction force is formed by providing a coil 5 fixedly connected to the carrier 4 on the carrier 4, so that the movement of the carrier 4 is controlled by controlling the magnitude and direction of the current input to the coil 5, and the position of the Z-axis movement is controlled by the Hall magnet 8 fixed on the carrier 4.

[0048] A coil 5 is sleeved on the carrier 4, and a magnet 7 for forming a magnetic field is provided on the bracket 1. The movement of the carrier 4 in the bracket 1 is controlled by energizing the coil 5; the upper spring sheet 2 includes two identical groups of elastic components arranged on the same plane, and the elastic components include an outer spring sheet 2.1 fixed on the bracket 1 and an inner spring sheet 2.2 arranged on the carrier 4; the outer spring sheet 2.1 and the inner spring sheet 2.2 are connected by four strings 2.3 and provide elastic restoring force.

[0049] Because the movement of the carrier 4 is achieved through the joint action of two spring sheets and the coil 5, the precise displacement is achieved through the Hall magnet 8 fixed on the carrier 4 and the sensor on the bracket 1 to achieve precise positioning. In the voice coil motor with OIS anti-shake function, the lower spring sheet 3 needs to provide a restoring force on the X / Y plane, so the upper spring sheet 2 needs to have a good rebound effect and good stability and structural strength. In order to improve the service life and reduce the difficulty of processing and manufacturing, the upper spring sheet 2 is divided into two identical parts in this embodiment. The carrier 4 and the bracket 1 are both annular structures, and the upper spring sheet 2 is divided into two identical structural rings and is symmetrical about the center point of the bracket 1 during installation. In order to provide better rebound performance, an inner and outer two-layer fixed connection structure is formed by fixing the spring sheet 2.1 on the bracket 1 and the spring sheet 2.3 on the carrier 4, and 4 strings 2.3 are used for connection.

[0050] like Figure 1 As shown, because the carrier 4 and the bracket 1 are both annular structures and the center hole is used to install the lens module, the gap between the carrier 4 and the bracket 1 is small, but according to the elastic characteristics and laws of the material, increasing the length of the lever arm can increase the yield strength under the premise of using the same material, that is, the local large deformation caused by the short lever arm state is evenly distributed in each section of the material after increasing the material length.

[0051] Therefore, the only way to avoid the spring sheet from breaking due to fatigue when the carrier 4 moves is to increase the length of the string 2.3. Figure 2 As can be seen in the figure, the string 2.3 starts from the outer spring piece 2.1 and extends circumferentially along the central axis of the carrier 4 to form four identical string wires.

[0052] Embodiment 2:

[0053] This embodiment specifically discloses a Z-axis zoom component of a VCM motor, such as Figure 1-7 As shown, it can be seen in the overall diagram that it mainly includes a bracket 1, an upper spring sheet 2 arranged on both sides of the bracket 1, a lower spring sheet 3 and a carrier 4 structure arranged in the bracket 1.

[0054] It can be seen in the figure that the bracket 1 and the carrier 4 are a set of annular components nested inside and outside, because the bracket 1 is provided with a carrier 4 that can move on the Z axis on the bracket 1, and the carrier 4 is connected to the upper spring sheet 2 and the lower spring sheet 3 and provides a restoring force through the upper spring sheet 2 and the lower spring sheet 3. In the case that the coil is not energized and the magnet does not generate magnetic force, the gravity on the entire carrier 4 and the pulling force of the two spring sheets form a static balance, and at this time, the carrier 4 is in a suspended state relative to the bracket 1.

[0055] An annular groove is provided at the bottom of the carrier 4, and a coil 5 is sleeved on the groove. The coil 5 can be fixed on the carrier 4 by direct winding or glue-point baking and curing assembly, and the carrier 4 is pushed to move by energizing the coil 5 to form a magnetic field with the magnet 7 of the bracket 1.

[0056] In order to form a fixed magnetic field, in this embodiment, a magnet 7 for forming a magnetic field is provided on the bracket 1, and the carrier 4 is controlled to move in the Z-axis direction on the bracket 1 by energizing the coil 5; the upper spring sheet 2 includes two identical groups of elastic components arranged on the same plane, and the elastic components include an outer spring sheet 2.1 fixed on the bracket 1 and an inner spring sheet 2.2 arranged on the carrier 4; the outer spring sheet 2.1 and the inner spring sheet 2.2 are connected by 4 strings 2.3 and provide elastic restoring force.

[0057] A control line and a power supply line are provided inside the bracket 1, and a contact A connected to the control line and a contact B connected to the power supply line are provided on the surface of one side of the upper spring sheet 2, and the contact A and the contact B are arranged in the gap between the two elastic components; the outer spring sheet 2.1 of the elastic component is in contact with the contact A and the contact B, and the inner spring sheet 2.2 of the elastic component is connected to the contact C arranged on the carrier 4 for connecting the coil 5.

[0058] like Figure 5 As shown in the figure, the material used as the circuit is moved outward as a whole to form a schematic diagram. In fact, the circuit is integrally injection molded using conductive materials or metal stampings. Because the bracket 1 is a structure arranged in the voice coil motor to limit the axial movement of the carrier 4, the carrier 4 is provided with a coil 5, and the coil 5 needs to be electrically connected to the upper spring sheet to form a conductive wire, and the upper spring sheet is divided into an inner and outer ring structure. The inner ring structure and the carrier 4 contact are welded using solder paste, and the outer ring structure and the upper part of the frame are welded using conductive silver paste or soldering or laser welding. In this embodiment, the one-piece casting method is to modify the PCB or flexible wiring method to a structure in which the conductive material is directly injected to form a circuit or a metal stamping circuit is integrally injection molded. Generally, voice coil motors adopt a split circuit design. The soft board or PCB board needs to be manually assembled and fixed with glue. Multiple independent connection components are set separately, which not only reduces the assembly efficiency, but also affects the yield. The conductive material used in this embodiment is directly cast or the metal stamping circuit is integrally injection molded to form a regular solid circuit belt in the housing of the bracket 1. When installing, it is only necessary to fix the components and use conductive silver paste, soldering or laser welding to achieve conduction connection, which is convenient and quick.

[0059] In order to form a closed-loop control, a Hall magnet 8 is fixed on the inner side of the carrier 4 for easy induction with the sensor, and a Hall sensor corresponding to the positioning permanent magnet for information feedback is provided on the bracket 1. When the carrier 4 moves, the positioning permanent magnet is displaced relative to the Hall sensor, so that the magnet is positioned by the Hall sensor and the data is sent to the control IC, thereby achieving the effect of feedback regulation.

[0060] The bracket 1 is provided with a groove for facilitating the string 2.3 to swing up and down, and the bracket 1 is provided with a positioning column for fixing the upper spring sheet 2. Figure 7 This is a diagram showing the upper end surface structure of a single bracket 1. In the diagram, it can be seen that the outer ring of the upper end surface of the bracket 1 is provided with a positioning column and a bearing surface for fixing the outer spring sheet 2.1, and the inner side is provided with a limit groove and a sink structure. The outer spring sheet 2.1 is fixed on the outer edge surface of the bracket 1 and is fixed by multiple positioning columns, and the connection between the string 2.3 and the outer spring sheet 2.1 is widened to improve the structural strength of the connection part.

[0061] The inner side of the carrier 4 is provided with a hole for fixing the lens module, while the outer side of the carrier 4 is provided with four guide blades 6, and the inner side of the bracket 1 is provided with four limit grooves for cooperating with the guide blades 6 to realize linear motion.

[0062] The control wiring and power supply wiring in the bracket 1 are both formed by injection molding a basic material with conductive function with a circuit design together with the base material of the bracket 1. The bracket 1 is provided with at least four mounting grooves on the side where the lower spring sheet 3 is provided, and the magnet 7 is nested in the mounting groove by glue fixing and in the mounting groove.

Claims

1. A Z-axis zoom assembly of a VCM motor, which is arranged outside a lens module and uses electromagnetic control to make the lens module move in a directional manner to change the focal length, characterized in that: It comprises a bracket (1) and an upper spring sheet (2) and a lower spring sheet (3) arranged on both sides of the bracket (1); The support (1) is provided with a carrier (4) which can move linearly in the support (1); the carrier (4) is connected to the upper spring sheet (2) and the lower spring sheet (3) and provides a restoring force through the upper spring sheet (2) and the lower spring sheet (3); The carrier (4) is sleeved with a coil (5), and a magnet (7) for forming a magnetic field is provided on the bracket (1). The movement of the carrier (4) in the bracket (1) is controlled by energizing the coil (5); The upper spring sheet (2) comprises two identical groups of elastic components arranged on the same plane, the elastic components comprising an outer elastic sheet (2.1) fixed on the bracket (1) and an inner elastic sheet (2.2) arranged on the carrier (4); The outer spring piece (2.1) and the inner spring piece (2.2) are connected by a plurality of strings (2.3) and provide elastic restoring force; A Hall magnet (8) is fixedly provided on the inner side of the carrier (4) for facilitating induction positioning, and a Hall sensor is provided on the bracket (1) for providing information feedback corresponding to the Hall magnet (8); The carrier (4) is provided with a guide blade (6) on the outside, and the bracket (1) is provided with a plurality of limit grooves cooperating with the guide blade (6) to realize limit linear motion.

2. The Z-axis zoom assembly of a VCM motor according to claim 1, characterized in that: The support (1) is provided with a control wiring and a power supply wiring inside, and a contact A connected to the control wiring and a contact B connected to the power supply wiring are provided on a surface of one side provided with the upper spring sheet (2), and the contact A and the contact B are provided at the gap between the two elastic components; The outer spring sheet (2.1) of the elastic component is in contact with the contact A and the contact B, and the inner spring sheet (2.2) of the elastic component is connected to a contact C arranged on the carrier (4) for connecting the coil (5).

3. A Z-axis zoom assembly of a VCM motor according to claim 1 or 2, characterized in that: The bracket (1) is provided with a groove for facilitating the string to swing up and down.

4. The Z-axis zoom assembly of a VCM motor according to claim 1 or 2, characterized in that: The bracket (1) is provided with a positioning column for fixing the upper spring sheet (2).

5. The Z-axis zoom assembly of a VCM motor according to claim 1 or 2, characterized in that: A through hole for fixing the lens module is provided on the inner side of the carrier (4).

6. The Z-axis zoom assembly of a VCM motor according to claim 2, characterized in that: The control wiring and the power supply wiring in the bracket (1) are both formed by injection molding a circuit design of a conductive material or a metal stamping part having a conductive function together with a bracket substrate.

7. The Z-axis zoom assembly of a VCM motor according to claim 1 or 2, characterized in that: The bracket (1) is provided with at least four installation grooves on the side where the lower spring sheet (3) is provided, and the magnets (7) are nested in the installation grooves.

8. The Z-axis zoom assembly of a VCM motor according to claim 7, characterized in that: The inner surface of the installation groove is provided with a plurality of strip-shaped protruding glue storage grooves for providing glue storage for the magnet.

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