JP2019020507A - Lens drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively limit the movement of a movable member in a lens driving device by making the occupied area of the base member as small as possible with respect to the opening diameter of the base member and without requiring high processing accuracy for forming the base member. To be able to do it. SOLUTION: A lens driving device has a base member having an opening in a central portion, a movable member to which a lens or a lens frame is attached, and a movable member elastically movable with respect to the base member along the optical axis direction of the lens. The base member includes an elastic support member that supports the lens and an actuator that applies a thrust force along the optical axis direction of the lens to the movable member. A contact surface is provided in the portion to limit the movement of the movable member around the optical axis and the movement in the plane direction intersecting the optical axis. [Selection diagram] Fig. 1

Description

  The present invention relates to a lens driving device.

  The lens driving device includes a base member, a movable member (carrier) to which a lens or a lens frame (lens barrel) is attached, and a support member that supports the movable member movably along the optical axis direction of the lens with respect to the base member. One of the actuator coil and magnet is provided on the movable member, the other is provided on the support member, and the movable member supported by the support member via an elastic member such as a leaf spring is used as the thrust of the actuator. It moves along the optical axis direction while balancing the (Lorentz force) and the elastic force of the elastic member (see, for example, Patent Document 1 below).

  In the conventional lens driving device, the movable member is pressed against the base member by the elastic force of the elastic member when the actuator is not energized. The base member is moved in the optical axis direction of the movable member and around the optical axis. A movement restriction unit for restricting movement is provided.

Japanese Patent Laying-Open No. 2015-99282

  The above-described conventional lens driving device requires a large space for providing a movement limiting portion and a part of the actuator on the bottom surface of the base member. For this reason, there existed a problem that the occupation area of a base member became large with respect to the opening diameter of a base member.

  In addition, since the movement restricting portion is provided at a position relatively close to the center of the base member, in order to restrict movement around the optical axis near the outer peripheral edge of the movable member, the clearance between the movement restricting member and the movable member is limited. Is required to be as small as possible, and it has been a problem that high processing accuracy is required to form the base member.

  In the conventional lens driving device described above, a movable member or actuator is disposed on the base member, and then the movable member or actuator is covered with a cover, and the lower end edge of the cover is bonded and fixed to the outer peripheral edge of the base member. It was. At this time, there is a concern that the adhesive may enter the inside due to a capillary phenomenon, and may adhere to a movable member and cause malfunction.

  In particular, when trying to meet the demand to reduce the area occupied by the base member as much as possible with respect to the opening diameter of the base member, the outer peripheral edge of the base member into which the adhesive is necessarily injected and the internal parts such as the movable member As a result, there is a problem that the risk of the adhesive interfering with internal parts is increased.

  An object of the present invention is to deal with such a problem. That is, in the lens driving device, it is possible to effectively limit the movement of the movable member without reducing the area occupied by the base member as much as possible with respect to the opening diameter of the base member, and without requiring high processing accuracy for forming the base member. It is an object of the present invention to be able to do this, to suppress internal interference of the adhesive when the cover is bonded to the base member.

In order to solve such a problem, the present invention has the following configuration.
A base member having an opening in the center, a movable member to which a lens or a lens frame is attached, and an elastic support member that elastically supports the movable member with respect to the base member so as to be movable along the optical axis direction of the lens; An actuator for applying a thrust along the optical axis direction of the lens to the movable member, and the base member includes a wall portion standing in the optical axis direction in the vicinity of an outer peripheral edge, A lens driving device comprising a contact surface for restricting movement of the movable member around the optical axis and movement in a planar direction intersecting the optical axis.

It is a disassembled perspective view of the lens drive device concerning the embodiment of the present invention. (A) is a perspective view of a base member, (b) is a side view of a base member. (A) is a bottom view of a movable member, (b) is X1-X1 sectional drawing of (a). (A) is a side view of a movable member, (b) is the A section enlarged view of (a). It is explanatory drawing which showed the relationship between a base member, a movable member, an elastic support member (lower leaf | plate spring), and a cover. It is explanatory drawing which showed the arrangement | positioning relationship between a base member, a movable member, and an elastic support member (upper leaf | plate spring). (A) is the longitudinal cross-sectional view which showed the whole structure of the lens drive device, (b) is the B section enlarged view. (A) is an imaging device provided with a lens drive device, (b) is explanatory drawing which shows the portable electronic device (mobile information terminal) provided with the lens drive device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals in different drawings indicate parts having the same function, and repeated description in each drawing will be omitted as appropriate.

  As shown in FIG. 1, the lens driving device 1 includes a base member 2 having an opening 2 </ b> A in the center, a movable member 3 in which a lens or a lens frame is attached to the center opening 3 </ b> A, and a movable member with respect to the base member 2. An elastic support member (plate spring) 4 that elastically supports 3, an actuator (coil 6 and magnet 7) 5 that applies thrust to the movable member 3, and a cover (yoke) 8 that covers the movable member 3 and the elastic support member 4. I have.

  The base member 2 has a rectangular outer peripheral edge 2B, and is provided with a cover support portion 2C that supports the lower end 8B of the cover 8 along the outer peripheral edge 2B. A wall 2D is provided inside 2C. The wall 2D is erected along the direction of the optical axis O of the lens attached to the movable member 3. Further, the base member 2 is provided with a support portion 2E having a triangular shape in plan view at a corner portion of a rectangular outer peripheral edge 2B.

  The movable member 3 is provided with a screw portion for screwing the lens or the lens frame on the inner surface of the opening 3A, and the coil 6 which is a part of the actuator 5 is wound around the optical axis O of the lens on the side surface. The coil holding part 3B is provided. In addition, a spring support portion 3C that supports the inner support portion 4A of the elastic support member 4 is provided above and below the coil holding portion 3B. In the example shown in the drawing, the movable member 3 has an octagonal outer peripheral edge so as to be arranged inside a support portion 2 </ b> E having a triangular shape in plan view provided at a corner portion of the base member 2.

  The elastic support member 4 elastically supports the movable member 3 movably along the optical axis O direction of the lens, and includes one upper elastic support member (upper leaf spring) 40 and a lower divided into four parts. An elastic support member (lower plate spring) 41 is included. The upper elastic support member 40 is provided with two inner support portions 40A that are fixed to the spring support portion 3C of the movable member 3, and is supported by a space above the support portion 2E provided at the corner of the base member 2. Four portions 40B are provided, and elastic deformation portions 40C that connect the inner support portion 40A and the outer support portion 40B are provided at four locations. Each of the four lower elastic support members 41 includes an inner support portion 41 </ b> A that is fixed to the spring support portion 3 </ b> C of the movable member 3 and an outer support that is fixed to the support portion 2 </ b> E provided at the corner of the base member 2. 41B and the elastic deformation part 41C which connects 41 A of inner side support parts, and the outer side support part 41B are provided.

  The actuator 5 includes the coil 6 described above and a magnet 7 disposed in a space above the support portion 2E provided at the corner of the base member 2. The magnet 7 is magnetized in a direction from the four corners of the cover 8 toward the optical axis O, and forms a magnetic field in which magnetic lines of force are directed in a direction perpendicular to the coil 6 wound around the optical axis O. Accordingly, a thrust (Lorentz force) in the optical axis O direction is applied to the movable member 3 that holds the coil 6 by energization of the coil 6.

  The magnet 7 arranged in the space above the support portion 2E provided at the corner of the base member 2 is fixed to the inner surface of the cover 8, and the outer support portion 41B of the upper elastic support member 40 is fixed to the upper surface of the magnet 7. Has been. The cover 8 has an opening 8A in the center, and is formed of a magnetic material, thereby functioning as a yoke to which the magnet 7 is magnetically attracted.

  The base member 2 and the movable member 3 will be described in more detail with reference to FIGS. The wall portion 2D of the base member 2 is provided with a contact surface 10 (10A to 10H) that restricts the movement of the movable member 3 around the optical axis O and the movement in the plane direction intersecting the optical axis O. The base member 2 is provided with a contact surface 11 that restricts excessive movement of the movable member 3 in the direction of the optical axis O as a plane perpendicular to the optical axis O.

  The contact surfaces 10 (10A to 10H) provided on the wall portion 2D of the base member 2 are brought into contact with the contact surfaces 12A to 12H of the contact portion 12 provided on the lower surface of the movable member 3, whereby the light of the movable member 3 is obtained. Movement around the axis O and movement in the plane direction intersecting the optical axis O are restricted.

  The contact portion 12 provided in the movable member 3 is provided so as to protrude downward from the lower surface of the movable member 3, and includes a convex portion 12P protruding outward in a direction intersecting the optical axis O. On the other hand, the wall 2D of the base member 2 is provided with two recesses 2D1 at positions facing each other across the opening 2A, and the protrusions 12P of the contact portions 12 are disposed in the recesses 2D1, respectively. ing.

  The contact surface 10 on the base member 2 side is provided with a pair of contact surfaces 10A, 10B (10E, 10F) along the outer periphery of the base member 2 in the recess 2D1 provided in the wall 2D. , 10D (10G, 10H) are provided on the inner surface of the wall 2D. Here, the contact surface 10A and the contact surface 10B, the contact surface 10E and the contact surface 10F, the contact surface 10C and the contact surface 10G, and the contact surface 10D and the contact surface 10H are parallel surfaces that face each other.

  The contact surface 12A on the movable member 3 faces the contact surface 10A on the base member 2 side, and the contact surface 12B on the movable member 3 faces the contact surface 10B on the base member 2 side. doing. Similarly, the contact surface 12E on the movable member 3 side faces the contact surface 10E on the base member 2 side, and the contact surface 12F on the movable member 3 side faces the contact surface 10F on the base member 2 side. Face to face. Such contact surfaces 10A and 10B and contact surfaces 10E and 10F on the base member 2 side restrict movement of the movable member 3 in the Y direction (see FIG. 3) and around the optical axis O.

  Further, the contact surface 12C on the movable member 3 side faces the contact surface 10C on the base member 2 side, and the contact surface 12D on the movable member 3 side faces the contact surface 10D on the base member 2 side. doing. Similarly, the contact surface 12G on the movable member 3 faces the contact surface 10G on the base member 2 side, and the contact surface 12H on the movable member 3 side faces the contact surface 10H on the base member 2 side. Face to face. Such contact surfaces 10C and 10D and contact surfaces 10G and 10H on the base member 2 side restrict movement of the movable member 3 in the X direction (see FIG. 3).

  Further, the contact surface 12J provided on the bottom surface of the contact portion 12 of the movable member 3 faces the contact surface 11 of the base member 2, and thereby the movable member 3 moves excessively in the direction of the optical axis O. To prevent you from doing. For example, the excessive movement in the optical axis direction described above refers to movement that damages the elastically deforming portion of each elastic support member.

  As described above, in this embodiment, by providing contact surfaces on the base member 2 and the movable member 3, respectively, movement in the direction perpendicular to the optical axis, movement around the optical axis, and movement in the optical axis direction are performed. It can be limited appropriately.

  Further, the base member 2 has an input terminal 13 for driving current input to the coil 6 protruding from the bottom surface, and a conductive wire (not shown) conducting to the input terminal 13 is disposed inside the base member 2. A connection terminal 14 that is electrically connected to the conductive wire is provided on the surface of the support portion 2 </ b> E in the base member 2. In addition, the base member 2 is provided with a groove portion 2G for allowing a projection 3F of the movable member 3 described later to escape.

  As shown in FIGS. 3 and 4, a protrusion 3 </ b> F protrudes downward from the movable member 3, and a lead-out portion 6 </ b> A of the coil 6 is wound around the protrusion 3 </ b> F. The protruding portion 3F has an inversely tapered side surface 3m whose cross section increases toward the protruding end (lower end). When the lead-out portion 6A of the coil 6 is wound around the projection 3F having the reverse tapered side surface 3m, it is difficult to cause a problem that the winding is released or the lead-out portion 6A is detached from the projection 3F.

  The end of the coil 6 is connected to the lower elastic support member 41 and is connected to the connection terminal 14 of the base member 2 via the lower elastic support member 41 having conductivity. The end portion of the coil 6 is soldered to the inner support portion 41A of the lower elastic support member 41. In order to improve workability at that time, the lead-out portion 6A of the coil 6 is wound around the protruding portion 3F. By making the protruding portion 3F have an inversely tapered shape, it is possible to prevent the drawing portion 6A from being unwound and coming off, so that workability when connecting the terminals of the coil 6 is further improved.

  As shown in FIG. 5, the lower elastic support member 41 is divided into four parts, each including an inner support part 41A, a triangular outer support part 41B, and an elastic deformation part 41C. The two lower elastic support members 41 </ b> X and 41 </ b> Y among them form an energization path to the coil 6. In the lower elastic support members 41X and 41Y, the inner support portion 41A is bonded and fixed to the spring support portion 3C in the vicinity of the protrusion 3F of the movable member 3, and the end of the lead-out portion 6A of the coil 6 wound around the protrusion 3F. The part is connected to the inner support part 41A with solder or the like. The outer support portions 41B of the lower elastic support members 41X and 41Y are bonded and fixed to the support portions 2E of the base member 2, and the connection terminals 14 provided on the support portions 2E and the outer support portions 41B are connected by soldering or the like. .

  As shown in FIG. 6, the upper elastic support member 40 has a rectangular outer edge shape corresponding to the outer peripheral edge shape of the base member 2, and triangular outer support portions 40 </ b> B are provided at four corners. The outer support portion 40 </ b> B of the upper elastic support member 40 is adhesively fixed to the upper surface of the magnet 7 that is disposed in the space above the support portion 2 </ b> E of the base member 2 and is fixed to the inner surface of the cover 8. The inner support portion 40 </ b> A of the upper elastic support member 40 is bonded and fixed to a spring support portion 3 </ b> C provided on the upper surface of the movable member 3. The inner support portion 40A of the upper elastic support member 40 has an adhesive inlet 42 in a notch shape. After the inner support portion 40 </ b> A is placed on the spring support portion 3 </ b> C of the movable member 3, the adhesive is injected into the adhesive injection port 42. As a result, the adhesive is filled between the lower surface of the inner support portion 40A and the upper surface of the spring support portion 3C by capillary action.

  An assembling procedure of such a lens driving device 1 will be described. First, the outer support portion 40B of the upper elastic support member 40 is fixed to the inside of the top surface of the cover 8 with an adhesive. Next, an adhesive is applied to the upper surface and the side surface of the magnet 7, and the upper surface of the magnet 7 is fixed to the outer support portion 40 </ b> B of the upper elastic support member 40 fixed to the inside of the top surface of the cover 8. Is fixed to the inner surface of the cover 8. Since the magnet 7 has side surfaces corresponding to the corners of the cover 8 and the cover 8 is a magnetic body that functions as a yoke, the magnet 7 is magnetically attracted to the inner surface of the cover 8, and the magnet 7 and the cover Fixing to 8 can be performed relatively easily.

  On the other hand, for the base member 2, the outer support portion 41B of the lower elastic support member 41 is fixed to the support portion 2E with an adhesive. The coil 6 is wound around the coil holding portion 3B, and the lead portion 6A of the coil 6 is wound around the lower spring support portion 3C of the movable member 3 wound around the protrusion 3F. The support portion 41A is fixed with an adhesive. Thereafter, the end portion of the coil 6 is soldered to the inner support portion 41A of the lower elastic support member 41, and the outer support portion 41B of the lower elastic support member 41 is connected to the connection terminal 14 provided on the support portion 2E of the base member 2. Soldered.

  Thereafter, the cover 8 in which the upper elastic support member 40 and the magnet 7 are fixed inside, and the base member 2 in which the lower elastic support member 41 and the movable member 3 are fixed inside the wall portion 2D are combined. At this time, by applying an adhesive to the upper spring support portion 3C of the movable member 3, the spring support portion 3C and the inner support portion 41A of the upper elastic support member 40 are fixed. Finally, the lower end 8B of the cover 8 is placed on the cover support portion 2C of the base member 2, and the adhesive is injected from the adhesive injection port 8C of the cover 8, whereby the outer surface of the wall portion 2C of the base member 2 is injected. And the inner surface of the cover 8 are fixed with an adhesive.

  At this time, as shown in FIGS. 2 and 7, an adhesive surface 2 </ b> H is provided on the outer surface of the wall portion 2 </ b> D of the base member 2 via a step 2 t, and this adhesive surface 2 </ b> H is formed on the inner surface of the cover 8. Bonded via an adhesive. The adhesive injected from the adhesive injection port 8C of the cover 8 enters the gap between the adhesive surface 2H and the inner surface of the cover 8 and spreads over the entire surface of the adhesive surface 2H by capillary action. Since the surface 2H is formed on the outer surface of the wall 2D through the step 2t, the adhesive does not spread beyond the step 2t. Thus, it is possible to prevent the adhesive from entering other than the bonding surface 2H and interfering with the internal components.

  As shown in FIG. 2, the step 2t that partitions the bonding surface 2H is formed at a position spaced from the recess 2D1 of the wall 2D. For this reason, an adhesive agent does not enter into the concave portion 2D1 in which the convex portion 12P of the contact portion 12 of the movable member 3 is disposed inside. Thereby, the movable member 3 is prevented from malfunctioning due to the interference of the adhesive.

  In the above description, the spring support portion 3C of the movable member 3 to which the inner support portion 40A of the upper elastic support member 40 and the inner support portion 41A of the lower elastic support member 41 are fixed, or the outer support portion of the lower elastic support member 41. The support portion 2E of the base member 2 to which 41B is fixed is a flat surface to which an adhesive is applied, and is not configured with positioning convex portions or step portions. With such a configuration, it is possible to prevent the assembly position from being shifted due to the position error of the positioning part, and it is possible to omit the space for providing the convex portion and the step portion. At the time of assembling, it is possible to assemble with high accuracy by assembling while correcting the position using image recognition (optical alignment).

  According to such a lens driving device 1, the base member 2 includes the wall portion 2D erected in the optical axis O direction in the vicinity of the outer peripheral edge 2B, and the wall portion 2D is provided around the optical axis O of the movable member 3. Since the contact surface 10 (10A to 10H) that restricts the movement and the movement in the plane direction intersecting the optical axis O is provided, the occupied area of the base member 2 is made as small as possible with respect to the diameter of the opening 2A. Even if it is a case, the contact surface 10 (10A-10H) used as a mechanical stopper with space efficiency can be provided.

  Since the base member 2 and the movable member 3 constitute a movement-restricted mechanical stopper, it is necessary to adjust the three components so that the movable member 3 is applied to the inner surface of the cover 8 fixed to the base member 2. Compared to a simple configuration, the influence of the dimensional variation between components is reduced, and the lens driving device 1 with less wobbling can be obtained with a reduced clearance between contact surfaces. Furthermore, since the contact surface that becomes the mechanical stopper is provided in the vicinity of the outer peripheral edge 2B of the base member 2, the movement of the movable member 3 around the optical axis O can be particularly efficiently limited. Such a lens driving device 1 is capable of suppressing the impact at the time of dropping, can suppress the generation of dust accompanying damage to the elastic support member (leaf spring) 4 and collision between components, and has high operational reliability and resistance. The lens driving device 1 with high impact can be obtained.

  8A shows an imaging device (camera) 100 including the lens driving device 1 described above in FIG. 8A, and FIG. 8B shows a portable electronic device (portable information) including a camera unit including the lens driving device 1 in FIG. Terminal) 200.

  The lens driving device 1 described above can reduce the installation space in the imaging device (camera) 100 and the portable electronic device (portable information terminal) 200 by reducing the area occupied by the base member 2. As a result, the imaging device (camera) 100 and the portable electronic device (personal digital assistant) 200 can be reduced in size and thickness, and the functional area of the device can be enhanced by increasing the installation area of other functional components. It becomes possible.

  Further, since the lens driving device 1 described above has high impact resistance and durability, it is appropriate when the imaging device (camera) 100 and the portable electronic device (portable information terminal) 200 with improved mobile performance are used. Lens driving performance can be exhibited. Furthermore, since the lens driving device 1 described above has high operation reliability and can improve the manufacturing yield, the high-performance and low-cost of the imaging device (camera) 100 and the portable electronic device (portable information terminal) 200 can be obtained. It can correspond to the conversion.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention. In addition, the above-described embodiments can be combined by utilizing each other's technology as long as there is no particular contradiction or problem in the purpose and configuration.

1: Lens drive device,
2: base member, 2A: opening, 2B: outer peripheral edge, 2C: cover support,
2D: wall, 2D1: recess, 2E: support, 2G: groove, 2H: adhesion surface, 2t: step,
3: movable member, 3A: opening, 3B: coil holding part, 3C: spring support part,
3F: protrusion, 3m: side surface,
4: Elastic support member (leaf spring), 4A, 40A, 41A: inner support part,
4B, 40B, 41B: outer support part, 4C, 40C, 41C: elastic deformation part,
40: Upper elastic support member (upper leaf spring),
41, 41X, 41Y: lower elastic support member (lower leaf spring), 42: adhesive injection port,
5: Actuator, 6: Coil, 6A: Pull-out part, 7: Magnet,
8: Cover (yoke), 8A: Opening, 8B: Lower end, 8C: Adhesive inlet,
10 (10A to 10H), 11: contact surface,
12: Contact part, 12A-12H, 12J: Contact surface, 12P: Convex part,
13: input terminal, 14: connection terminal,
100: imaging device (camera), 200: portable electronic device (portable information terminal),
O: Optical axis

Claims (11)

A base member having an opening in the center,
A movable member to which a lens or a lens frame is attached;
An elastic support member that elastically supports the movable member in a movable manner along the optical axis direction of the lens with respect to the base member;
An actuator for applying a thrust along the optical axis direction of the lens to the movable member;
The base member includes a wall portion standing in the optical axis direction in the vicinity of an outer peripheral edge,
The lens driving device according to claim 1, wherein a contact surface that restricts movement of the movable member around the optical axis and movement in a planar direction intersecting the optical axis is provided on the wall portion.   The lens driving device according to claim 1, wherein a pair of the contact surfaces are provided along an outer periphery of the base member and are provided on an inner surface of the wall portion.   The lens driving device according to claim 1, wherein the wall portion includes a contact surface that restricts excessive movement of the movable member in the optical axis direction.   The lens driving device according to claim 1, wherein the contact surface is provided in a concave portion of the wall portion, and the movable member includes a convex portion disposed in the concave portion. . The outer peripheral edge of the base member is rectangular,
The outer side of the elastic support member is supported at the corner of the base member,
The lens driving device according to claim 1, wherein an outer peripheral edge of the movable member has an octagonal shape. A cover for covering the movable member and the actuator is provided on the base member,
The outer surface of the wall is provided with an adhesive surface through a step,
The lens driving device according to claim 1, wherein the bonding surface is bonded to the inner surface of the cover via an adhesive. A magnet that is a part of the actuator is disposed on a corner of the base member,
A coil that is a part of the actuator is wound around the optical axis around the movable member,
The lens driving device according to claim 6, wherein the cover is a yoke. The movable member is provided with a protrusion around which the coil drawing portion is wound,
The lens driving device according to claim 7, wherein an end portion of the coil is connected to a terminal portion of the base member via the elastic support member.   The lens driving device according to claim 8, wherein the protrusion has an inversely tapered side surface having a transverse section that increases toward the protrusion end.   The imaging device provided with the lens drive device of any one of Claims 1-9.   The portable information terminal provided with the lens drive device of any one of Claims 1-9.

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