JP2014010281A - Lens drive device and adjustment method for lens drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device able to restrict variation in start current through simple adjustment while simplifying the inventory management of components to be used, even if the spring characteristics, etc., of a spring member connecting a movable body and a fixing body varies.SOLUTION: A lens drive device 1 comprises: a movable body holding a lens; a fixing body holding the movable body; a driving coil 20 fixed to the movable body; a driving magnet 21 fixed to the fixing body; a spring member 5 connecting the movable body and fixing body; and a magnetic member 13 that energizes the movable body toward a reference position in the direction of an optical axis by magnetic attraction force generated between the driving magnet 21 and itself. Formed on the subject side of the movable body are: a mounting face for mounting the magnetic member 13 on it; an internal wall part 8d extending up toward the subject from the internal circumferential side of the mounting face; and a plurality of external wall parts 8f extending up toward the subject from the outer circumferential side of the mounting face. Spaces are formed between the plurality of external wall parts 8f in the direction of lens circumference.

Description

  The present invention relates to a lens driving device mounted on a relatively small camera used in a mobile phone or the like. The present invention also relates to a method for adjusting such a lens driving device.

  Conventionally, as a lens driving device for driving a photographing lens of a camera mounted on a mobile phone or the like, a moving body that holds the lens and moves in the optical axis direction, and a support that holds the moving body so as to be movable in the optical axis direction A lens driving device including a body, a driving coil and a driving magnet for driving the moving body in the optical axis direction is known (see, for example, Patent Documents 1 and 2). In the lens driving devices described in Patent Documents 1 and 2, a driving coil is attached to a moving body, and a driving magnet is attached to a support. Further, in this lens driving device, the moving body and the support body are connected by leaf springs disposed on both ends of the moving body in the optical axis direction.

  Further, in the lens driving devices described in Patent Documents 1 and 2, the leaf springs arranged on the subject side among the leaf springs arranged on both ends of the moving body in the optical axis direction are circles fixed to the moving body. An annular first fixing part, a second fixing part fixed to the support, and a plurality of arm parts connecting the first fixing part and the second fixing part are provided. The leaf spring is fixed to the moving body and the support body with the arm portion bent, and the moving body is moved toward the reference position of the moving body in the optical axis direction by the urging force of the leaf spring. It is energized.

  In the lens driving device described in Patent Document 1, an annular magnetic member is disposed between the first fixed portion of the leaf spring and the portion of the moving body where the first fixed portion is fixed. In this lens driving device, a magnetic attractive force acts between the magnetic member and the driving magnet fixed to the support, and in addition to the urging force of the leaf spring disposed on the subject side, The moving body is also biased toward the reference position of the moving body in the optical axis direction by this magnetic attraction force.

  Further, in the lens driving device described in Patent Document 2, a circular magnetic piece holding hole is formed on the subject side of the moving body. The magnetic piece holding holes are formed at the four corners of the movable body when viewed from the optical axis direction, and each of the four magnetic piece holding holes has a spherical magnetic shape. A piece is housed. In this lens driving device, a magnetic attractive force acts between the magnetic piece and the driving magnet fixed to the support, and in addition to the urging force of the leaf spring disposed on the subject side, The moving body is also biased toward the reference position of the moving body in the optical axis direction by this magnetic attraction force. In this lens driving device, the number of the magnetic pieces accommodated in the magnetic piece holding hole is changed, or the size of the magnetic piece accommodated in the magnetic piece holding hole is changed, so that the magnetic piece and the driving magnet are changed. It is possible to adjust the biasing force of the moving body in the direction toward the reference position by adjusting the magnetic attraction force between the two, and as a result, to start the moving body at the reference position The necessary drive coil current (starting current) can be adjusted.

JP 2008-275952 A JP 2008-116901 A

  As described above, in the lens driving devices described in Patent Documents 1 and 2, the biasing force of the leaf spring disposed on the subject side and the magnetic attractive force between the magnetic member or the magnetic piece and the driving magnet are used. The moving body is biased toward the reference position of the moving body in the optical axis direction. Therefore, in this lens driving device, the starting current varies if the spring characteristics of the leaf spring arranged on the subject side, the magnetic force of the driving magnet, etc. vary, and the urging force of the moving body in the direction toward the reference position varies. Therefore, the characteristics of the lens driving device vary.

  In this case, in the lens driving device described in Patent Document 1, it is possible to adjust the magnetic attractive force between the magnetic member and the driving magnet by adjusting the thickness and width of the magnetic member. It is possible to suppress variations in the starting current by suppressing variations in the biasing force of the moving body in the direction toward the reference position. However, in this case, since it is necessary to prepare a plurality of types of magnetic members having different thicknesses and widths, the management of components becomes complicated, and some types of magnetic members among the plurality of types of magnetic members are There is also a risk of remaining in stock without being used.

  On the other hand, in the lens driving device described in Patent Document 2, when the urging force of the moving body in the direction toward the reference position varies due to variations in the spring characteristics of the leaf springs arranged on the subject side, the magnetic piece is retained. By changing the number and size of the magnetic pieces accommodated in the holes, it is possible to suppress variations in the urging force of the moving body in the direction toward the reference position, thereby suppressing variations in starting current. However, even in this lens driving device, since it is necessary to prepare a plurality of types of magnetic pieces having different sizes, the management of parts becomes complicated, and some types of magnetic pieces among the plurality of types of magnetic pieces are There is also a risk of remaining in stock without being used.

  Here, in the lens driving device described in Patent Document 2, without preparing a plurality of types of magnetic pieces having different sizes, the position of the magnetic piece accommodated in the magnetic piece holding hole is adjusted, By adjusting the distance from the driving magnet, the magnetic attractive force between the magnetic piece and the driving magnet can be adjusted to suppress variations in the biasing force of the moving body in the direction toward the reference position. As a result, variations in starting current can be suppressed. However, in this lens driving device, it is necessary to adjust the positions of the magnetic pieces arranged at the four corners of the moving body, so that the adjustment work becomes complicated.

  Therefore, the problem of the present invention is that even if the spring characteristics of the spring member connecting the movable body and the fixed body vary, the inventory management of the parts to be used is simplified and the variation in the starting current is suppressed by easy adjustment. It is an object of the present invention to provide a lens driving device that can perform the above-described operation. Moreover, the subject of this invention is providing the adjustment method of this lens drive device.

  In order to solve the above problems, a lens driving device of the present invention includes a movable body that holds a lens and is movable in the optical axis direction of the lens, a fixed body that holds the movable body so as to be movable in the optical axis direction, and a movable body. A driving coil fixed to the body, a driving magnet fixed to the fixed body so as to face the driving coil, a spring member connecting the movable body and the fixed body, and movable on the subject side relative to the driving magnet An annular magnetic member that urges the movable body toward the reference position of the movable body in the optical axis direction by a magnetic attraction force generated between the fixed body and the driving magnet. The mounting surface for mounting the magnetic member is formed so as to surround the lens, and the inner wall portion rises from the inner peripheral side of the mounting surface toward the subject side, and rises from the outer peripheral side of the mounting surface toward the subject side. A plurality of outer walls and In the circumferential direction, and wherein a gap between the plurality of outer walls are formed.

  The lens driving device of the present invention includes an annular magnetic member that urges the movable body toward the reference position of the movable body in the optical axis direction by a magnetic attraction generated between the lens driving device and the driving magnet. In the present invention, on the subject side of the movable body, a mounting surface for mounting the magnetic member is formed so as to surround the lens, and an inner wall portion rising from the inner peripheral side of the mounting surface toward the subject side; A plurality of outer wall portions rising from the outer peripheral side of the mounting surface toward the subject side are formed. Therefore, in the present invention, even if the spring characteristics of the spring member vary, the distance between the magnetic member and the driving magnet is adjusted by adjusting the position of the magnetic member in the optical axis direction between the inner wall portion and the outer wall portion. By adjusting, it is possible to adjust the magnetic attractive force between the magnetic member and the driving magnet, and to suppress variation in the urging force of the movable body in the direction toward the reference position. Therefore, in the present invention, it is possible to suppress variations in starting current without preparing a plurality of types of magnetic members having different thicknesses and widths. That is, according to the present invention, it is possible to suppress variations in starting current while simplifying inventory management of parts used in the lens driving device.

  Further, in the present invention, it is only necessary to adjust the position in the optical axis direction of one magnetic member formed in an annular shape. Therefore, the position of the magnetic member can be easily adjusted, and as a result, the variation in starting current can be easily adjusted. become. That is, according to the present invention, even if the spring characteristics of the spring member vary, it is possible to suppress variations in the starting current with easy adjustment. In the present invention, since gaps are formed between a plurality of outer wall portions in the circumferential direction of the lens, the position of the magnetic member can be adjusted while picking the annular magnetic member with tweezers or the like using the gap. It becomes possible. Therefore, in the present invention, it becomes easier to move the magnetic member when adjusting the position of the magnetic member, and as a result, the position adjustment of the magnetic member becomes easier.

  In the present invention, the lens driving device is formed so as to have a substantially rectangular shape when viewed from the optical axis direction, and the driving magnet is formed in a substantially flat plate shape when viewed from the optical axis direction. It is arranged along each of the four sides of the lens driving device, and the movable body has four outer wall portions, and the four outer wall portions are arranged at the four corners of the lens driving device, respectively. preferable. If comprised in this way, since an outer wall part is arrange | positioned in the four corners of the lens drive device which is likely to become a dead space, it becomes possible to miniaturize a lens drive device in the direction orthogonal to the optical axis direction.

  In the present invention, the spring member includes a movable body fixing portion fixed to the subject side of the movable body, a fixed body fixing portion fixed to the fixed body, and an arm portion connecting the movable body fixing portion and the fixed body fixing portion. It is preferable that the subject side end surface of the outer wall portion is a spring fixing surface to which the movable body fixing portion is fixed. If comprised in this way, it will become unnecessary to provide the structure for fixing a movable body fixing | fixed part in a movable body separately. Therefore, the configuration of the movable body can be simplified.

  In the present invention, the height of the inner wall portion and the outer wall portion in the optical axis direction is preferably higher than the thickness of the magnetic member. If comprised in this way, it will become possible to enlarge the adjustment width | variety of the position of the magnetic member in an optical axis direction.

  In the adjustment method of the lens driving device of the present invention, for example, an adhesive is applied between the inner wall portion and the outer wall portion and between the mounting surface and the magnetic member, and the optical axis is changed depending on the thickness of the adhesive. Adjust the position of the magnetic member in the direction. In this case, since it is not necessary to provide a member for adjusting the position of the magnetic member in the optical axis direction, it is possible to prevent an increase in the number of parts of the lens driving device.

  In the lens driving device adjustment method of the present invention, a flat plate-shaped adjustment member made of a nonmagnetic material is disposed between the mounting surface and the magnetic member, and the position of the magnetic member in the optical axis direction is determined by the number of adjustment members. May be adjusted. In this case, the position adjustment of the magnetic member can be performed with higher accuracy than the case of adjusting the position of the magnetic member in the optical axis direction with the adhesive. Even in this case, if the position of the magnetic member in the direction of the optical axis is adjusted by the number of one type of adjusting member, there will be no problem that the management of the adjusting member becomes complicated.

  As described above, in the lens driving device of the present invention, even if the spring characteristics of the spring member vary, it is possible to simplify the inventory management of the parts used and to suppress the variation in the starting current with easy adjustment. become. Further, in the adjustment method of the lens driving device according to the present invention, when the distance between the driving magnet and the magnetic member is adjusted by the thickness of the adhesive, it is possible to prevent an increase in the number of parts of the lens driving device. When the distance between the driving magnet and the magnetic member is adjusted by the number of adjusting members, the position of the magnetic member can be adjusted with high accuracy.

It is a perspective view of the lens drive device concerning an embodiment of the invention. It is sectional drawing of the EE cross section of FIG. It is a disassembled perspective view of the lens drive device shown in FIG. It is a top view of the leaf | plate spring shown in FIG. FIG. 4 is a perspective view of the sleeve shown in FIG. 3. FIG. 6 is a plan view of the sleeve shown in FIG. 5. It is an enlarged view of the F section of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Schematic configuration of lens driving device)
FIG. 1 is a perspective view of a lens driving device 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line EE of FIG. FIG. 3 is an exploded perspective view of the lens driving device 1 shown in FIG. FIG. 4 is a plan view of the leaf spring 5 shown in FIG. In the following description, as shown in FIG. 1 and the like, the three directions orthogonal to each other are defined as an X direction, a Y direction, and a Z direction. The X direction is the left-right direction, the Y direction is the front-rear direction, and the Z direction is the up-down direction. The Z1 direction side is the “upper” side, and the Z2 direction side is the “lower” side.

  The lens driving device 1 of this embodiment is mounted on a relatively small camera used in a mobile phone, a drive recorder, a surveillance camera system, or the like, and is formed in a substantially quadrangular prism shape as a whole as shown in FIG. Has been. Specifically, the lens driving device 1 is formed so that the shape of the lens for photographing when viewed from the direction of the optical axis L (optical axis direction) is a substantially square shape. The four side surfaces of the lens driving device 1 are substantially parallel to the left-right direction or the front-rear direction.

  In this embodiment, the Z direction (vertical direction) is substantially coincident with the optical axis direction. In addition, in a camera equipped with the lens driving device 1 of the present embodiment, an imaging element (not shown) is arranged on the lower side, and a subject arranged on the upper side is photographed. That is, in this embodiment, the upper side (Z1 direction side) is the subject side (object side), and the lower side (Z2 direction side) is the anti-subject side (imaging element side, image side).

  As shown in FIGS. 1 and 2, the lens driving device 1 includes a movable body 2 that holds a photographing lens and is movable in the optical axis direction, and a fixed body that holds the movable body 2 so as to be movable in the optical axis direction. 3 and a drive mechanism 4 for driving the movable body 2 in the optical axis direction. Moreover, the lens drive device 1 includes leaf springs 5 and 6 that connect the movable body 2 and the fixed body 3 as shown in FIGS. That is, the movable body 2 is movably held by the fixed body 3 via the leaf springs 5 and 6. In this embodiment, the leaf spring 5 is disposed on the upper end side of the movable body 2, and the leaf spring 6 is disposed on the lower end side of the movable body 2.

  The movable body 2 includes a sleeve 8 that holds a lens holder 7 to which a plurality of lenses are fixed. The fixed body 3 includes a cover member 10 that constitutes the upper end portion of the side surface of the lens driving device 1, a base member 11 that constitutes the lower end portion of the side surface of the lens driving device 1 and the lower end surface of the lens driving device 1, and a plate And a spacer 12 to which a part of the spring 5 is fixed. An annular magnetic member 13 made of a soft magnetic material is fixed to the upper end side of the sleeve 8. A pair of power supply terminals 14 for supplying a current to a driving coil 20 (described later) that constitutes the driving mechanism 4 is fixed to the base member 11. In addition, illustration of the lens holder 7 is abbreviate | omitted in FIG.

  The lens holder 7 is formed in a substantially cylindrical shape. A plurality of lenses are fixed on the inner peripheral side of the lens holder 7. The sleeve 8 is formed of, for example, a resin material and has a substantially cylindrical shape. Specifically, the sleeve 8 has a substantially cylindrical shape in which the shape of the inner peripheral surface when viewed from the optical axis direction is substantially circular, and the shape of the outer peripheral surface when viewed from the optical axis direction is substantially square. Is formed. The sleeve 8 holds the lens holder 7 on its inner peripheral side. At the lower end of the sleeve 8, a projection 8 a that contacts a later-described reference surface 11 b formed on the base member 11 and determines the reference position of the movable body 2 in the optical axis direction is formed so as to protrude downward. Yes. The protrusions 8a are formed at four locations at a 90 ° pitch with the optical axis L as the center. A more specific configuration of the sleeve 8 will be described later.

  The cover member 10 is made of a magnetic metal material. Moreover, the cover member 10 is formed in the substantially square cylinder shape with the bottom which has the bottom part 10a and the cylinder part 10b. A through hole 10c is formed at the center of the bottom 10a disposed on the upper side. The cover member 10 covers the outer peripheral side of the movable body 2 and the drive mechanism 4.

  The base member 11 is formed of an insulating resin material. The base member 11 is formed in a block shape having a substantially square shape when viewed from the optical axis direction. The base member 11 is attached to the lower end side of the cover member 10. A through hole 11 a is formed at the center of the base member 11. Further, on the upper surface of the base member 11, a reference surface 11b for determining the reference position of the movable body 2 in the optical axis direction is formed in a planar shape orthogonal to the optical axis direction. The reference surfaces 11b are formed at four locations at a 90 ° pitch with the optical axis L as the center. In this embodiment, when the lower end surface of the protruding portion 8a of the sleeve 8 is in contact with the reference surface 11b, the movable body 2 is at the reference position in the optical axis direction.

  The spacer 12 is formed of, for example, a resin material and is formed in a substantially square flat block shape. The spacer 12 is formed in a frame shape, and a through hole is formed at the center thereof. The spacer 12 is fixed to the lower surface of the bottom 10 a of the cover member 10. Fixing body fixing portions 5b, which will be described later, constituting the leaf spring 5 are bonded and fixed to the lower surface sides of the four corners of the spacer 12, respectively.

  The leaf spring 5 is formed in a plate shape from a metal material. As shown in FIG. 4, the leaf spring 5 includes a movable body fixing portion 5a fixed to the upper end side of the sleeve 8, four fixed body fixing portions 5b fixed to the spacer 12, and a movable body fixing portion 5a. And four arm portions 5c that connect the fixed body fixing portion 5b. The movable body fixing | fixed part 5a is formed in the annular | circular shape. The fixed body fixing | fixed part 5b is formed in the substantially rectangular shape, and is arrange | positioned at the outer peripheral side rather than the movable body fixing | fixed part 5a. In addition, each of the four fixed body fixing portions 5 b is disposed at each of the four corners of the lens driving device 1. The arm portion 5c is formed in a substantially ¼ arc shape so that desired spring characteristics of the leaf spring 5 can be obtained. The leaf spring 5 of this embodiment is a spring member that connects the movable body 2 and the fixed body 3.

  The leaf spring 5 is fixed to the sleeve 8 and the spacer 12 so that the thickness direction and the optical axis direction substantially coincide. The fixed body fixing portion 5b is disposed below the movable body fixing portion 5a in the movable range of the movable body 2, and the leaf spring 5 is in a state where the arm portion 5c is always bent and the sleeve 8 and It is fixed to the spacer 12. Therefore, the movable body 2 is always urged downward by the urging force of the leaf spring 5. That is, the movable body 2 is biased toward the reference position in the optical axis direction of the movable body 2 where the lower end surface of the protrusion 8 a of the sleeve 8 abuts on the reference surface 11 b of the base member 11 by the biasing force of the leaf spring 5. Has been.

  The leaf spring 6 is composed of two spring pieces 15 that are electrically separated from each other. The spring piece 15 is formed in a plate shape by a conductive metal material. The spring piece 15 includes two movable body fixing portions fixed to the lower end side of the sleeve 8, two fixed body fixing portions fixed to the base member 11, and two connecting the movable body fixing portion and the fixed body fixing portion. Arm. The spring piece 15 is electrically connected to an end portion of a drive coil 20 that will be described later that constitutes the drive mechanism 4. The spring piece 15 is fixed to the sleeve 8 and the base member 11 so that the thickness direction and the optical axis direction substantially coincide. Further, the spring piece 15 is fixed to the sleeve 8 and the base member 11 so that the urging force of the movable body 2 by the spring piece 15 does not occur when no current is supplied to the drive coil 20 described later. .

  The power supply terminal 14 is made of a conductive metal material. One of the two power supply terminals 14 is electrically connected to one of the two power supply terminals 14, and the other spring piece 15 is electrically connected to the other power supply terminal 14. Has been. The power supply terminal 14 is fixed to the base member 11.

  The drive mechanism 4 includes a drive coil 20 that is wound around the outer periphery of the sleeve 8 and a drive magnet 21 that is disposed along each of the four side surfaces of the lens drive device 1. The driving coil 20 is wound around the outer peripheral surface of the sleeve 8 and is fixed to the sleeve 8. The drive magnet 21 is formed in a substantially rectangular flat plate shape. The driving magnet 21 is fixed to the inner surface of the cylindrical portion 10b of the cover member 10 so as to face the outer peripheral surface of the driving coil 20 in the front-rear direction or the left-right direction. That is, the driving magnet 21 is disposed along each of the four sides of the lens driving device 1 when viewed from the vertical direction. The cover member 10 of this embodiment fulfills the function of a yoke for forming a magnetic circuit.

(Sleeve configuration and magnetic member arrangement, etc.)
FIG. 5 is a perspective view of the sleeve 8 shown in FIG. FIG. 6 is a plan view of the sleeve 8 shown in FIG. FIG. 7 is an enlarged view of a portion F in FIG.

  On the outer peripheral side of the sleeve 8, a flange portion 8 b that protrudes outward in the radial direction is formed. The flange portion 8b is formed at two locations on the upper end side and the lower end side of the sleeve 8. A driving coil 20 is wound between the two flange portions 8b. A mounting surface 8 c for mounting the magnetic member 13 is formed on the upper end side of the sleeve 8. The mounting surface 8c is formed in a substantially annular shape so as to surround the lens. The mounting surface 8c is formed in a planar shape substantially orthogonal to the optical axis direction. Further, the mounting surface 8c is formed above the upper surface of the flange portion 8b formed on the upper end side. Further, the mounting surface 8 c is always disposed above the driving magnet 21 in the movable range of the movable body 2.

  Further, an inner wall portion 8d that rises upward from the inner peripheral side of the mounting surface 8c is formed on the upper end side of the sleeve 8. The inner wall portion 8d is formed in a substantially cylindrical shape with the optical axis L as the axis center. The inner peripheral surface of the inner wall portion 8 d constitutes a part of the inner peripheral surface of the sleeve 8. A notch 8e that is cut out in a substantially rectangular shape from the upper end of the inner wall 8d to the lower side is formed on both ends in the front-rear direction and one end in the left-right direction of the inner wall 8d.

  Further, on the upper end side of the sleeve 8, a plurality of outer wall portions 8f rising from the outer peripheral side of the mounting surface 8c toward the upper side are formed. In this embodiment, four outer wall portions 8 f are formed on the upper end side of the sleeve 8. The outer wall portion 8f is formed in a substantially arc-shaped curved surface with the optical axis L as the center of curvature, and the four outer wall portions 8f are formed at a pitch of about 90 ° with the optical axis L as the center. That is, a gap S is formed between the four outer wall portions 8f in the circumferential direction of the lens (the circumferential direction of the sleeve 8). Further, the four outer wall portions 8f are formed at the four corners of the sleeve 8 where the shape of the outer peripheral surface when viewed from the optical axis direction is substantially square, and are arranged at the four corners of the lens driving device 1, respectively. Has been. As shown in FIG. 7, the upper end surface of the outer wall portion 8f is a spring fixing surface 8g to which the movable body fixing portion 5a of the leaf spring 5 is bonded and fixed.

  The height of the inner wall portion 8d in the vertical direction is higher than the height of the outer wall portion 8f. Further, the height of the inner wall portion 8 d and the outer wall portion 8 f in the vertical direction is higher than the thickness of the magnetic member 13. Further, the distance between the outer peripheral surface of the inner wall portion 8 d and the inner peripheral surface of the outer wall portion 8 f in the radial direction of the lens (the radial direction of the sleeve 8) is wider than the width of the magnetic member 13.

  The magnetic member 13 is fixed to the mounting surface 8c directly or via an adhesive 24 described later. Further, as described above, the mounting surface 8 c is always disposed above the driving magnet 21 in the movable range of the movable body 2. That is, the magnetic member 13 is fixed to the sleeve 8 above the drive magnet 21. Therefore, the movable body 2 is always urged downward by a magnetic attractive force generated between the magnetic member 13 and the driving magnet 21. In other words, due to the magnetic attractive force between the magnetic member 13 and the driving magnet 21, the movable body 2 has the light of the movable body 2 in which the lower end surface of the protrusion 8 a of the sleeve 8 contacts the reference surface 11 b of the base member 11. It is biased toward the reference position in the axial direction. Further, as described above, the movable body 2 is also biased toward the reference position in the optical axis direction by the biasing force of the leaf spring 5. That is, the movable body 2 is urged toward the reference position in the optical axis direction by the urging force of the leaf spring 5 and the magnetic attractive force between the magnetic member 13 and the driving magnet 21.

  In this embodiment, even if the urging force of the movable body 2 toward the reference position in the optical axis varies due to variations in the spring characteristics of the leaf spring 5, the magnetic force of the driving magnet 21 or the dimensions of the sleeve 8, etc. In order to adjust the force and suppress variation in the biasing force, the fixing position of the magnetic member 13 in the optical axis direction is adjusted when the lens driving device 1 is assembled, and the distance between the magnetic member 13 and the driving magnet 21 is adjusted. Is adjusted to adjust the magnetic attractive force between the magnetic member 13 and the driving magnet 21. Specifically, when the lens driving device 1 is assembled, the adhesive 24 applied between the inner wall 8d and the outer wall 8f and between the magnetic member 13 and the mounting surface 8c (FIG. 7 ( The fixing position of the magnetic member 13 in the optical axis direction is adjusted according to the thickness of (B).

  The spring characteristics of the leaf springs 5 produced in the same production lot are estimated to be stable to some extent, the magnetic force of the drive magnet 21 produced with the same production rod is estimated to be stable to some extent, It is estimated that the dimensions of the sleeve 8 produced with the same production rod are somewhat stable. Therefore, in this embodiment, the biasing force of the movable body 2 of several lens driving devices 1 using the leaf springs 5 and the like produced with the same rod is measured to determine the thickness of the adhesive 24 and the movable body. In the lens driving device 1 in which the plate spring 5 or the like of the lens driving device 1 in which the urging force of 2 is measured and the plate spring 5 or the like having the same production rod is used, the adhesive 24 having the determined thickness is applied to the inner wall portion 8d and the outer wall portion. 8f and between the magnetic member 13 and the mounting surface 8c.

  For example, when the biasing force of the movable body 2 measured at the time of assembling the lens driving device 1 is small, the distance between the magnetic member 13 and the driving magnet 21 is shortened, and the magnetic member 13 and the driving magnet 21 are reduced. In order to increase the magnetic attractive force between them, as shown in FIG. 7A, the adhesive 24 is not applied between the magnetic member 13 and the mounting surface 8c. That is, in this case, the thickness of the adhesive 24 applied between the magnetic member 13 and the mounting surface 8c is set to zero. On the other hand, when the urging force of the movable body 2 measured at the time of assembling the lens driving device 1 is large, the distance between the magnetic member 13 and the driving magnet 21 is increased to increase the distance between the magnetic member 13 and the driving magnet 21. In order to weaken the magnetic attraction force between them, as shown in FIG. 7 (B), there is a predetermined gap between the inner wall portion 8d and the outer wall portion 8f and between the magnetic member 13 and the mounting surface 8c. A thick adhesive 24 is applied.

  When the lens driving device 1 is assembled, the adhesive 24 is applied between the inner wall 8d and the outer wall 8f and between the magnetic member 13 and the mounting surface 8c. After the cured adhesive 24 is cured, the magnetic member 13 is mounted on the upper surface of the adhesive 24. Thereafter, an adhesive is applied between the inner wall portion 8 d and the outer wall portion 8 f to fix the magnetic member 13 to the sleeve 8. When the lens driving device 1 is assembled, if the adhesive 24 is not applied between the magnetic member 13 and the mounting surface 8c, the inner wall 8d and the outer wall are mounted after the magnetic member 13 is mounted on the mounting surface 8c. An adhesive is applied between the portion 8 f and the magnetic member 13 is fixed to the sleeve 8.

(Main effects of this form)
As described above, in this embodiment, on the upper end side of the sleeve 8, the mounting surface 8c for mounting the magnetic member 13, the inner wall portion 8d rising upward from the inner peripheral side of the mounting surface 8c, and the mounting surface A plurality of outer wall portions 8f rising from the outer peripheral side of 8c toward the upper side are formed. Further, in this embodiment, the magnetic member 13 in the optical axis direction depends on the thickness of the adhesive 24 applied between the inner wall portion 8d and the outer wall portion 8f and between the magnetic member 13 and the mounting surface 8c. By adjusting the fixing position of the magnetic member 13 and adjusting the distance between the magnetic member 13 and the driving magnet 21, the magnetic attraction force between the magnetic member 13 and the driving magnet 21 is adjusted, and the optical axis direction is adjusted. Variations in the urging force of the movable body 2 toward the reference position are suppressed. Therefore, in this embodiment, even if the spring characteristics of the leaf spring 5 vary, it is possible to suppress variations in the starting current of the lens driving device 1 by using one type of magnetic member 13. That is, in this embodiment, it is possible to suppress variations in the starting current of the lens driving device 1 without preparing a plurality of types of magnetic members 13 having different thicknesses and widths. It is possible to suppress variations in starting current while simplifying inventory management of used parts.

  In this embodiment, the position of the magnetic member 13 can be easily adjusted because the position of the single magnetic member 13 formed in an annular shape in the optical axis direction may be adjusted. Therefore, in this embodiment, even if the spring characteristics of the leaf spring 5 vary, it is easy to adjust the variation in the starting current. In this embodiment, since the gap S is formed between the four outer wall portions 8f in the circumferential direction of the sleeve 8, the gap S is used to grip the annular magnetic member 13 with tweezers or the like. The position of the member 13 can be adjusted. Therefore, in this embodiment, the magnetic member 13 can be easily moved when the position of the magnetic member 13 is adjusted. Further, since the gap S is formed between the four outer wall portions 8f, the adhesive 24 can be easily applied between the inner wall portion 8d and the outer wall portion 8f using the gap S. As a result, in this embodiment, the position adjustment of the magnetic member 13 becomes easier.

  In the present embodiment, four outer wall portions 8f are arranged at each of the four corners of the lens driving device 1 formed so as to have a substantially square shape when viewed from the optical axis direction. That is, in this embodiment, the outer wall portions 8f are arranged at the four corners of the lens driving device 1 that is likely to become a dead space. Therefore, in this embodiment, the lens driving device 1 can be reduced in size in the front-rear and left-right directions.

  In this embodiment, the upper end surface of the outer wall portion 8f is a spring fixing surface 8g to which the movable body fixing portion 5a of the leaf spring 5 is fixed. Therefore, in this embodiment, it is not necessary to separately provide the sleeve 8 with a configuration for fixing the movable body fixing portion 5a. Therefore, in this embodiment, the configuration of the sleeve 8 can be simplified.

  In this embodiment, the height of the inner wall portion 8 d and the outer wall portion 8 f in the vertical direction is higher than the thickness of the magnetic member 13. Therefore, in this embodiment, it is possible to increase the adjustment width of the position of the magnetic member 13 in the optical axis direction. In this embodiment, the inner wall 8d and the outer wall 8f can prevent the adhesive 24 applied between the inner wall 8d and the outer wall 8f from flowing out.

  In this embodiment, the fixing position of the magnetic member 13 in the optical axis direction is determined between the inner wall portion 8d and the outer wall portion 8f and the thickness of the adhesive 24 applied between the magnetic member 13 and the mounting surface 8c. Is adjusted. Therefore, in this embodiment, there is no need to provide a member for adjusting the fixing position of the magnetic member 13 in the optical axis direction. Therefore, in this embodiment, an increase in the number of parts of the lens driving device 1 can be prevented.

  In this embodiment, since the gap S is formed between the four outer wall portions 8f, the magnetic member 13 and the driving magnet 21 are compared with the case where the outer wall portion 8f is formed in a cylindrical shape. It is possible to reduce the distance. Therefore, in this embodiment, the magnetic attractive force between the magnetic member 13 and the drive magnet 21 can be increased. In the present embodiment, the four outer wall portions 8f are formed at a substantially 90 ° pitch with the optical axis L as the center, and the gap S formed between the four outer wall portions 8f is also centered on the optical axis L. Therefore, the magnetic attractive force between the magnetic member 13 and the driving magnet 21 is well balanced in the lens circumferential direction (the circumferential direction of the sleeve 8). Therefore, in this embodiment, it is possible to further stabilize the movable body 2 that is biased toward the reference position in the optical axis direction.

(Other embodiments)
The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention.

  In the embodiment described above, the magnetic member 13 is formed in an annular shape. In addition to this, for example, the magnetic member 13 may be formed in a square ring shape, or may be formed in a polygonal ring other than the square ring shape. In the embodiment described above, the mounting surface 8c is formed in a substantially annular shape so as to surround the lens, but the mounting surface 8c is, for example, a plurality of substantially arc-shaped planes having the optical axis L as the center of curvature. And it may be constituted by a plurality of planes arranged so as to surround the lens. In the embodiment described above, the upper end surface of the outer wall portion 8f is the spring fixing surface 8g to which the movable body fixing portion 5a of the leaf spring 5 is fixed, but the spring fixing surface to which the movable body fixing portion 5a is fixed. May be separately formed on the sleeve 8.

  In the embodiment described above, four outer wall portions 8f are formed on the upper end side of the sleeve 8, but the number of outer wall portions 8f formed on the upper end side of the sleeve 8 may be two or three. And 5 or more may be sufficient. In the embodiment described above, the leaf spring 5 includes the four arm portions 5c. However, the number of the arm portions 5c included in the leaf spring 5 may be two or three, or five. It may be above.

  In the embodiment described above, the magnetic member 13 is fixed in the optical axis direction by the thickness of the adhesive 24 applied between the inner wall portion 8d and the outer wall portion 8f and between the magnetic member 13 and the mounting surface 8c. The position is adjusted. In addition to this, for example, a flat plate-shaped adjustment member made of a nonmagnetic material is disposed between the mounting surface 8c and the magnetic member 13, and the fixing position of the magnetic member 13 in the optical axis direction is adjusted by the number of adjustment members. You may do it. In this case, the adjustment member is formed in an annular shape such as an annular shape, for example. Further, in this case, the position adjustment of the magnetic member 13 can be performed with higher accuracy than the case where the fixing position of the magnetic member 13 in the optical axis direction is adjusted by the adhesive 24. Even in this case, if the fixing position of the magnetic member 13 in the optical axis direction is adjusted by the number of one type of adjusting members, the problem that management of the adjusting members becomes complicated does not occur.

  In the embodiment described above, the lens driving device 1 is formed so that the shape when viewed from the optical axis direction is a substantially square shape, but the lens driving device 1 has a shape when viewed from the optical axis direction. You may form so that it may become a substantially rectangular shape. The lens driving device 1 may be formed so that the shape when viewed from the optical axis direction is a polygonal shape such as a substantially hexagonal shape, or a substantially circular shape or a substantially elliptical shape. Also good.

DESCRIPTION OF SYMBOLS 1 Lens drive device 2 Movable body 3 Fixed body 5 Leaf spring (spring member)
5a Movable body fixing portion 5b Fixed body fixing portion 5c Arm portion 8c Mounting surface 8d Inner wall portion 8f Outer wall portion 8g Spring fixing surface 13 Magnetic member 20 Driving coil 21 Driving magnet 24 Adhesive L Optical axis S Gap Z Optical axis direction Z1 Subject side

Claims (6)

A movable body that holds a lens and is movable in the optical axis direction of the lens, a fixed body that holds the movable body so as to be movable in the optical axis direction, a driving coil fixed to the movable body, and the drive A driving magnet fixed to the fixed body so as to face the coil, a spring member connecting the movable body and the fixed body, and the driving magnet fixed to the movable body on the subject side of the driving magnet. An annular magnetic member that urges the movable body toward a reference position of the movable body in the optical axis direction by a magnetic attraction generated between the magnet and the magnet
On the subject side of the movable body, a mounting surface for mounting the magnetic member is formed so as to surround the lens, and an inner wall portion rising from the inner peripheral side of the mounting surface toward the subject side; and A plurality of outer wall portions that rise from the outer peripheral side of the mounting surface toward the subject side are formed,
A lens driving device, wherein gaps are formed between the plurality of outer wall portions in the circumferential direction of the lens. Formed so that the shape when viewed from the optical axis direction is substantially rectangular,
The driving magnet is formed in a substantially flat plate shape, and is arranged along each of the four sides of the lens driving device when viewed from the optical axis direction.
Four outer wall portions are formed on the movable body,
The lens driving device according to claim 1, wherein the four outer wall portions are arranged at four corners of the lens driving device. The spring member includes a movable body fixing portion that is fixed to the subject side of the movable body, a fixed body fixing portion that is fixed to the fixed body, and an arm portion that connects the movable body fixing portion and the fixed body fixing portion. And
3. The lens driving device according to claim 1, wherein an end surface on the subject side of the outer wall portion is a spring fixing surface to which the movable body fixing portion is fixed.   4. The lens driving device according to claim 1, wherein heights of the inner wall portion and the outer wall portion in the optical axis direction are higher than a thickness of the magnetic member. 5. An adjustment method for a lens driving device according to any one of claims 1 to 4,
The position of the magnetic member in the optical axis direction is applied between the inner wall portion and the outer wall portion and between the mounting surface and the magnetic member, and depending on the thickness of the adhesive. A method for adjusting a lens driving device, comprising adjusting An adjustment method for a lens driving device according to any one of claims 1 to 4,
A flat plate-shaped adjusting member made of a nonmagnetic material is disposed between the mounting surface and the magnetic member, and the position of the magnetic member in the optical axis direction is adjusted by the number of the adjusting members. Adjustment method of lens driving device.

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