Position detection structure of focus motor and electronic device

Abstract

The utility model relates to the field of motor structure discloses a position detection structure and electronic equipment of focusing motor. The utility model discloses a position detection structure of focusing motor includes: carrier, drive magnet, set up the drive coil of carrier, base and the detection coil of inlay setting in base, drive magnet and drive coil interact, to drive carrier to move in focusing direction, drive coil and detection coil are opposite to set up, the relative position of drive coil and detection coil changes under the condition that carrier moves in focusing direction, and the moving distance of carrier is determined through the inductance of detection coil. Since the detection coil is inlayed in the base, the size of the motor does not need to be increased. And detection coil and base are formed with the same process, effectively control the manufacturing cost of motor.

Description

Technical Field

[0001] This utility model relates to the field of motor structure, and in particular to a position detection structure and electronic device for a focusing motor. Background Technology

[0002] Conventional open-loop focusing motors typically lack position detection components, making closed-loop control impossible and resulting in insufficient accuracy in motor control. To ensure accurate motor control, position detection components can be added to the motor. These components can then be used to determine the movement distance of the motor carrier, and consequently, the lens movement distance.

[0003] However, adding additional position detection components to the focusing motor increases the production cost of the motor structure and the manufacturing process. Utility Model Content

[0004] The purpose of this utility model embodiment is to provide a position detection structure and electronic device for a focusing motor. A detection coil is embedded in the base, and the moving distance of the carrier is determined by the mutual inductance effect between the detection coil and the drive coil. This eliminates the need to add extra components to the motor, effectively controlling the manufacturing cost of the motor.

[0005] To solve the above-mentioned technical problems, embodiments of this utility model provide a position detection structure for a focusing motor, comprising: a carrier, a driving magnet, a driving coil disposed on the carrier, a base, and a detection coil embedded in the base; the driving magnet interacts with the driving coil to drive the carrier to move in the focusing direction; the driving coil and the detection coil are disposed opposite to each other; when the carrier moves in the focusing direction, the relative position of the driving coil and the detection coil changes; the moving distance of the carrier is determined by the inductance of the detection coil.

[0006] An embodiment of this utility model also provides an electronic device, including the position detection structure of the focusing motor described above.

[0007] Compared to existing technologies, this embodiment of the invention features a drive coil mounted on a carrier, which, in conjunction with a drive magnet, drives the carrier. A detection coil is embedded within the base, positioned opposite the drive coil. When both the detection and drive coils are energized, mutual inductance exists between them. As the carrier moves in the focusing direction, the relative positions of the drive and detection coils change, causing a change in the inductance of the detection coil. Therefore, the movement distance of the carrier can be estimated by detecting the inductance of the detection coil. The detection coil's embedded placement within the base eliminates the need for additional internal space in the motor, facilitating miniaturization. Furthermore, the addition of the detection coil does not incur additional manufacturing processes compared to the original base, effectively controlling motor manufacturing costs.

[0008] In addition, the detection coil includes a main body and a first pin and a second pin located at both ends of the main body; the base includes a top surface and a side surface; the first pin and the second pin extend along the side surface of the base, and the main body is arranged parallel to the top surface of the base.

[0009] In addition, the first pin and the second pin extend from the same side of the base.

[0010] In addition, the position detection structure of the focusing motor also includes: a lens; the central area of ​​the base includes: a first channel; the first channel provides space for the movement of the lens; the detection coil is arranged around the first channel.

[0011] Additionally, the central region of the carrier includes a second channel; the second channel is used to accommodate the lens; and the drive coil is arranged around the second channel.

[0012] In addition, the position detection structure of the focusing motor also includes: an external circuit; the external circuit is electrically connected to the first pin and the second pin; the external circuit determines the current and voltage of the detection coil through the first pin and the second pin, and determines the inductance using the current and induced electromotive force of the detection coil.

[0013] In addition, the main body is wound to form a multi-turn conductive coil.

[0014] In addition, the position detection structure of the focusing motor includes: a sheet metal part embedded in the base, the sheet metal part including a first part and a second part respectively connected to an external circuit, the first part serving as the detection coil, and the second part serving as the conductive circuit of the drive coil. Attached Figure Description

[0015] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0016] Figure 1 This is a three-dimensional structural diagram of a position detection structure for a focusing motor according to an embodiment of this solution; Figure 2 This is a schematic diagram of the detection coil of a position detection structure for a focusing motor according to an embodiment of this solution; Figure 3 This is a schematic diagram of the combination structure of the detection coil and the base of a position detection structure for a focusing motor according to an embodiment of this solution; Figure 4 This is a schematic diagram of the combined structure of the detection coil and the drive coil of a position detection structure for a focusing motor according to an embodiment of this solution; Figure 5 This is a schematic diagram of the overall structure of a position detection structure for a focusing motor according to an embodiment of this solution; Figure 6 This is a diagram showing the relationship between the moving distance and the inductance of a position detection structure for a focusing motor according to an embodiment of this solution.

[0017] Figure label: 1-Carrier; 11-Second channel; 2-Drive magnet; 3-Drive coil; 4-Base; 41-Top surface; 42-Side; 43-First channel; 5-Detection coil; 51-Main body; 52-First pin; 53-Second pin; 6-Outer shell. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the various embodiments of this utility model will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this utility model to enable readers to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0019] The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of this utility model. The various embodiments can be combined with or referenced by each other without contradiction.

[0020] Embodiments of this utility model relate to a position detection structure for a focusing motor, such as... Figure 1 As shown, it includes: a carrier 1, a driving magnet 2, a driving coil 3 disposed on the carrier 1, a base 4, and a detection coil 5 embedded in the base 4; the driving magnet 2 interacts with the driving coil 3 to drive the carrier 1 to move in the focusing direction; the driving coil 3 and the detection coil 5 are disposed opposite each other; when the carrier 1 moves in the focusing direction, the relative position of the driving coil 3 and the detection coil 5 changes; the moving distance of the carrier 1 is determined by the inductance of the detection coil 5.

[0021] Specifically, when the carrier 1 moves away from the base, the position of the detection coil 5 remains unchanged because it is fixed to the base. However, the drive coil 3 is fixed to the carrier 1. Therefore, as the carrier 1 moves away from the detection coil 5, the distance between the drive coil 3 and the detection coil 5 increases. The magnetic field generated by the drive coil 3 weakens at the location of the detection coil 5. This weakening of the magnetic field at the detection coil 5 reduces the magnetic flux passing through it, decreasing the mutual inductance between the two coils. Consequently, the inductance of the detected coil 5 changes due to the mutual inductance. Therefore, when the mutual inductance changes with distance, the inductance of the detected coil also changes. Based on this change in inductance, the distance between the two coils can be determined, thus revealing the change in distance between the carrier and the base.

[0022] Compared to existing technologies, this embodiment of the invention features a drive coil mounted on a carrier, which, in conjunction with a drive magnet, drives the carrier. A detection coil is embedded within the base, positioned opposite the drive coil. When both the detection and drive coils are energized, mutual inductance exists between them. As the carrier moves in the focusing direction, the relative positions of the drive and detection coils change, causing a change in the inductance of the detection coil. Therefore, the movement distance of the carrier can be estimated by detecting the inductance of the detection coil. The detection coil's embedded placement within the base eliminates the need for additional internal space in the motor, facilitating miniaturization. Furthermore, the addition of the detection coil does not incur additional manufacturing processes compared to the original base, effectively controlling motor manufacturing costs.

[0023] The structure of the detection coil is as follows Figure 2 As shown, the detection coil includes a main body 51, and a first pin 52 and a second pin 53 located at both ends of the main body 51. Figure 2 The diagram shows the structure of a single-turn detection coil. To improve the inductive detection strength, the number of turns in the detection coil can be increased, such as... Figure 3As shown, this is a detection coil structure with 2 turns. The main body is wound to form a multi-turn conductive coil. The main body is bent to form a double-strand wire and then bent to form a two-turn conductive coil. In practical applications, the number of turns of the detection coil can be increased or decreased according to the required inductance strength.

[0024] In addition, such as Figure 3 As shown, the base 4 includes a top surface 41 and a side surface 42; the main body 51 is disposed parallel to the top surface 41 of the base, and the first pin 52 and the second pin 53 extend along the side surface 42 of the base, thereby facilitating the connection of the first pin and the second pin to an external circuit. The first pin 52 and the second pin 53 extend from the same side surface of the base and are disposed adjacent to each other.

[0025] like Figure 3 As shown, the position detection structure of the focusing motor also includes: a lens; the central area of ​​the base includes: a first channel 43; the first channel 43 is used to avoid the lens, preventing the lens from colliding with the base during lens movement and providing sufficient space for lens movement; a detection coil 5 (specifically, the main body 51 of the detection coil) is arranged around the first channel 43. And as... Figure 4 As shown, the central region of the carrier includes: a second channel 11; the second channel 11 is used to accommodate the lens; the drive coil 3 is arranged around the second channel 11, thus constituting one of the implementations in which the drive coil 3 and the detection coil 5 are positioned opposite each other.

[0026] In addition, the position detection structure of the focusing motor also includes: an external circuit; the external circuit is electrically connected to the first pin 52 and the second pin 53; the external circuit determines the current and voltage of the detection coil through the first pin 52 and the second pin 53, and determines the inductance using the current and induced electromotive force of the detection coil. Figure 5 As shown, in order to facilitate the connection of the first pin 52 and the second pin 53 to the external circuit, the first pin 52 and the second pin 53 are usually exposed outside the motor housing 6.

[0027] When the base is formed by injection molding, a sheet metal part can also be used to form the conductive circuit of the drive coil. The sheet metal part is embedded in the base and includes a first part and a second part, which are respectively connected to an external circuit. The first part serves as the detection coil, and the second part serves as the conductive circuit of the aforementioned drive coil. The current flow of the conductive circuit of the drive coil can be: positive terminal of external power supply, second part of sheet metal part, spring contact, drive coil, another spring contact, second part of sheet metal part, negative terminal of external power supply. The sheet metal part and the spring contact (including the upper spring contact and / or the lower spring contact) can be connected by welding, and the spring contact and the drive coil can also be connected by welding. In the above embodiment, the detection coil and the conductive circuit are each connected to the external circuit. It can be understood that the sheet metal part has four pins, two of which are used to connect to the external circuit to power the drive coil, and the other two are used to connect to the external circuit to power the detection coil. This realizes that the drive coil and the detection coil are independently electrically connected to the external circuit, and the detection coil is connected to the external circuit to provide power. When processing the sheet metal part, the detection coil and the conductive circuit can be processed using the same process, saving process steps.

[0028] In addition, in this solution, there is no need to install an IC in the motor. The moving distance of the carrier 1 can be determined by the IC in the external circuit based on the electrical signal generated by the mutual inductance between the drive coil and the detection coil.

[0029] In addition, the motor structure also includes an upper spring plate above the carrier and a lower spring plate below the carrier, which are used to limit the movement of the carrier.

[0030] To verify the practical application effect of this utility model embodiment, simulation tests were conducted on the inductance of the detection coil corresponding to different lens positions, and the results were as follows: Figure 6 The simulation diagram shown is from Figure 6 It can be seen that the inductance of the detection coil changes with the moving distance of the motor carrier, and the change in inductance and moving distance are almost linear. Only one inductance corresponds to the same moving distance. Therefore, the moving distance of the carrier can be determined based on the inductance of the detection coil. Since the lens is mounted on the carrier and moves synchronously with it, the moving distance of the lens can be determined from the moving distance of the carrier.

[0031] This utility model embodiment also relates to an electronic device, including the above-described position detection structure for a focusing motor.

[0032] Compared with related technologies, the electronic device provided in this embodiment of the present invention is provided with the position detection structure of the focusing motor provided in the aforementioned embodiment. Therefore, it also has the technical effects provided in the aforementioned embodiment, and will not be described in detail here.

[0033] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A position detection structure for a focusing motor, characterized in that, include: A carrier, a driving magnet, a driving coil disposed on the carrier, a base, and a detection coil embedded in the base; The driving magnet interacts with the driving coil to drive the carrier to move in the focusing direction; The driving coil is arranged opposite to the detection coil; When the carrier moves in the focusing direction, the relative position of the driving coil and the detection coil changes; the moving distance of the carrier is determined by the inductance of the detection coil.

2. The position detection structure for the focusing motor according to claim 1, characterized in that, The detection coil includes: a main body, and a first pin and a second pin respectively located at both ends of the main body; the base includes: a top surface and a side surface; The first pin and the second pin extend along the side of the base, and the main body is arranged parallel to the top surface of the base.

3. The position detection structure for the focusing motor according to claim 2, characterized in that, The first pin and the second pin extend from the same side of the base.

4. The position detection structure for the focusing motor according to claim 2 or 3, characterized in that, Also includes: Lens; The central region of the base includes: a first channel; the first channel provides space for the movement of the lens; The detection coil is arranged around the first channel.

5. The position detection structure for the focusing motor according to claim 4, characterized in that, The central region of the carrier includes a second channel; the second channel is used to accommodate the lens. The drive coil is arranged around the second channel.

6. The position detection structure for the focusing motor according to claim 2 or 3, characterized in that, Also includes: External circuitry; The external circuit is electrically connected to the first pin and the second pin; The external circuit determines the current and voltage of the detection coil through the first pin and the second pin, and determines the inductance using the current and induced electromotive force of the detection coil.

7. The position detection structure for the focusing motor according to claim 2, characterized in that, The main body is wound to form a multi-turn conductive coil.

8. The position detection structure for the focusing motor according to claim 1, characterized in that, include: The sheet metal part embedded in the base includes a first part and a second part that are respectively connected to an external circuit. The first part serves as the detection coil, and the second part serves as the conductive circuit of the drive coil.

9. An electronic device, characterized in that, include: The position detection structure of the focusing motor as described in any one of claims 1 to 8.

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