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KR-20260066899-A - Camera actuator

KR20260066899AKR 20260066899 AKR20260066899 AKR 20260066899AKR-20260066899-A

Abstract

A camera actuator is disclosed. A camera actuator according to one aspect of the present invention may include a base, an AF carrier, an OIS carrier, a first driving unit including a first coil and a first magnet, a second driving unit including a second coil and a second magnet, and a suction yoke. The suction yoke may include a first yoke adjacent to the stimulation of the first magnet furthest from the second magnet, and a second yoke adjacent to the stimulation of the second magnet furthest from the first magnet.

Inventors

  • 박창욱
  • 박찬우

Assignees

  • 자화전자(주)

Dates

Publication Date
20260512
Application Date
20241105

Claims (14)

  1. base; An OIS carrier accommodated in the above base and moving in a first direction or a second direction perpendicular to the optical axis direction; A first driving unit comprising a first magnet disposed on the first directional side of the OIS carrier, having a length in the second direction and forming a boundary of stimulation, and a first coil disposed facing the first magnet; A second driving unit comprising a second magnet disposed on the second directional side of the OIS carrier, having a length in the first direction and forming a boundary of stimulation, and a second coil disposed facing the second magnet; and, A suction yoke disposed having an area overlapping with the first magnet or the second magnet; comprising The above suction yoke is, A first yoke having an area overlapping with the first magnet and positioned adjacent to the magnetic pole of the first magnet that is furthest from the second magnet, and A camera actuator comprising a second yoke having an area overlapping with the second magnet and positioned adjacent to the magnetic pole of the second magnet, which is furthest from the first magnet.
  2. In Article 1, The above suction yoke is, A camera actuator arranged to have an area overlapping with the first magnet or the second magnet in the optical axis direction.
  3. In Article 1, The above suction yoke is, A camera actuator having a second region located adjacent to the magnetic pole of the first magnet or the second magnet based on a virtual centerline that divides the length equally, wherein the second region has a larger area than the adjacent first region.
  4. In Paragraph 3, The above suction yoke is, A camera actuator having a corner portion of the first region, which is far from the first coil or the second coil, formed as a chamfer.
  5. In Paragraph 3, The above suction yoke is a camera actuator that is inserted molded.
  6. In Paragraph 5, The above suction yoke is, A camera actuator comprising a protrusion extending toward the first coil or the second coil in the second region.
  7. In Article 1, The above suction yoke is, A camera actuator in which the first yoke and the second yoke have the same size and shape.
  8. In Article 1, The above-mentioned first magnet is, It includes a first-1 magnet and a first-2 magnet arranged adjacent to the first-1 magnet in a second direction, and The above second magnet is, A camera actuator comprising a second-1 magnet and a second-2 magnet arranged adjacent to the second-1 magnet in a first direction.
  9. In Paragraph 8, The first yoke is arranged to have an area that overlaps with the first-1 magnet in the optical axis direction, and The above second yoke is a camera actuator arranged to have an area that overlaps with the above second-2 magnet in the optical axis direction.
  10. In Article 9, The above-mentioned first yoke is, Based on a virtual centerline dividing the length, the area of the second region located adjacent to the outer magnetic pole of the first-1 magnet, which is far from the first-2 magnet, has a larger area than the area of the adjacent first region. The above second yoke is, A camera actuator formed such that the area of a second region located adjacent to the outer magnetic pole of the second-2 magnet, which is far from the second-1 magnet based on a virtual centerline dividing the length, has a larger area than the area of an adjacent first region.
  11. In Article 10, When implementing the OIS function in a first direction in which the first coil and the first magnet move away from each other, The above-mentioned first yoke is, The bottom line furthest from the above-mentioned first-1 coil is formed so as not to extend beyond the width direction boundary of the above-mentioned first-1 magnet closest to the above-mentioned first-1 coil, and The above second yoke is, A camera actuator formed such that the leading edge line at a position close to the 2-1 magnet does not extend beyond the boundary of the inner magnetic field of the 2-2 magnet close to the 2-1 magnet.
  12. In Article 10, When implementing the OIS function in the second direction in which the second coil and the second magnet move away from each other, The above-mentioned first yoke is, The leading edge line at a position close to the first-2 magnet is formed so as not to extend beyond the boundary of the inner magnetic field of the first-1 magnet close to the first-2 magnet, and The above second yoke is, A camera actuator formed such that the bottom line furthest from the above-mentioned second-2 coil does not extend beyond the width direction boundary of the above-mentioned second-2 magnet close to the above-mentioned second-2 coil.
  13. In Article 1, The above suction yoke is, A plate shape having an area defined by length and width, The above length is divided into a first region and a second region based on a virtual centerline that divides the length equally, A chamfer is formed at the corner where the leading line and the lower line of the first region are connected, and The upper line of the above second region extends with a protruding height to form an expanded area, A camera actuator formed such that the area of the second region is larger than the area of the first region.
  14. In Article 1, A camera actuator comprising an AF carrier that is accommodated in the base and moves in the optical axis direction together with the OIS carrier.

Description

Camera actuator The present invention relates to a camera actuator, and more specifically, to a camera actuator that enhances OIS driving characteristics through the arrangement structure of a suction yoke. As hardware technology for image processing advances, user demand for video recording and other related services is steadily increasing. Accordingly, functions such as zoom, AF (Auto Focus), and OIS (Optical Image Stabilizer) are implemented in camera actuators mounted on mobile terminals (hereinafter referred to as "electronic devices") as well as independent camera devices. One of the representative methods for implementing such AF or OIS functions is to form a driving unit by installing a magnet (or coil) on a carrier and another coil (or magnet) on a stationary body (such as a housing or another type of carrier), and then move the carrier in the direction of the optical axis or in a direction perpendicular to the optical axis by generating an electromagnetic force between the coil and the magnet. Meanwhile, in the case of a camera actuator with integrated AF and OIS functions, AF must move in the direction of the optical axis, and OIS must move in a direction perpendicular to the optical axis. To this end, a conventional camera actuator includes an AF drive unit composed of an AF coil and an AF magnet to generate a driving force in the direction of the optical axis, a first drive unit composed of a first coil and a first magnet to generate a driving force in a first direction (X-axis direction) perpendicular to the direction of the optical axis, and a second drive unit composed of a second coil and a second magnet to generate a driving force in a second direction (Y-axis direction) perpendicular to the direction of the optical axis. In addition, a conventional camera actuator discloses a structure in which an AF carrier and an OIS carrier are accommodated in a housing (fixed body) and stacked together in the direction of the optical axis. At this time, a ball is interposed between each component to continuously maintain an appropriate separation distance between the components, and the rotational movement of the ball and the minimized frictional force through point contact with the ball allow each carrier to move more flexibly and accurately for implementing AF and OIS functions. In addition, according to the embodiment, a middle guide supporting the OIS carrier is further included to control the rotation of the OIS carrier and induce linear movement in a direction perpendicular to the optical axis, thereby enabling stable OIS function implementation. Furthermore, a detection sensor is further included to accurately detect the movement of the AF carrier or OIS carrier and to control feedback correction. Meanwhile, current mobile devices (smartphones) are seeing lens sizes increase in response to consumer needs, and multiple lenses are being applied as required; furthermore, development directions are being explored to achieve miniaturization or slimming of the device. Accordingly, components such as AF carriers and OIS carriers must be stacked within a limited space, and development is being sought to optimize the placement of components within this limited space while simultaneously enhancing driving characteristics to ensure stable AF and OIS functions. In particular, while the implementation of the AF function can be characterized by considering movement and control in the optical axis direction (Z-axis direction), the implementation of the OIS function requires considering movement and control in directions perpendicular to the optical axis direction, namely the X-axis direction (first direction) and the Y-axis direction (second direction), so there were many difficulties in improving the driving characteristics. In particular, for camera actuators that do not include a middle guide, it was more difficult to improve OIS driving characteristics because there is no middle guide to induce linear movement while controlling unnecessary rotation of the OIS carrier. Accordingly, the drive unit was formed by separating it into multiple parts to prevent unnecessary rotational driving of the OIS carrier and to maintain linear driving while increasing driving force. For example, a structure has been disclosed in which the coils of the first direction and/or second direction of the OIS carrier are configured as two separate coils rather than a single coil, and the magnets facing them are also configured as two separate coils. Each is equipped with a driving driver to control them, thereby increasing the driving force and driving precision. Meanwhile, the suction yoke was positioned to generate a magnet and suction force in order to suppress unnecessary rotational drive components of the OIS carrier and enable linear movement. In other words, by utilizing the attractive force (suction force) acting between the magnet and the suction yoke to suppress the rotational drive of the OIS carrier and increase the rot