JP6482027B2 - Lens drive device - Google Patents

Description

  The present invention relates to a lens driving device mounted on a mobile device with a camera, for example.

  In recent years, it has become common for camera devices to be mounted on portable devices typified by mobile phones. In addition to the demand for downsizing, the lens driving device that is the main part of the camera mechanism mounted on this small portable device has a demand for driving the lens body (lens barrel on which the lens is mounted) with high accuracy. It has increased. As a lens driving device that satisfies these two requirements, a lens driving device provided with a magnetic circuit for driving a lens holder (lens holding member) for holding a lens body is well known.

  As the lens driving device described above, Patent Document 1 (conventional example) proposes a lens driving device 900 as shown in FIG. FIG. 12 is an exploded perspective view for explaining a conventional lens driving device 900.

  A lens driving device 900 shown in FIG. 12 includes a base member 901 in which a metal plate member is embedded, a lens holder 903 that can hold a lens body (not shown), and a coil 904 in which a metal wire is wound around the lens holder 903. , Four magnets 905 arranged to face the coil 904 at equal intervals, and an elastic member (a lower leaf spring 906 and a lower plate spring 906 and a lens holder 903 movably supported in the optical axis direction (Z direction shown in FIG. 12)). The upper plate spring 907), a yoke 908 made of a metal plate material, and a spacer member 909 formed in an annular shape are provided. When the lens driving device 900 is assembled, the base member 901 and the yoke 908 are integrated, and a lens holder (lens holding member) 903, a coil 904, four magnets 905, and the like are accommodated in the accommodation space. .

  The lens driving device 900 holds a lens body (not shown) on a lens holder 903 and is attached on a substrate on which an imaging element (not shown) is mounted. The lens driving device 900 can adjust the focal length by driving the lens held by the lens body in the optical axis direction (Z direction shown in FIG. 12) with respect to the imaging element. At that time, a magnetic circuit is formed by the four magnets 905 disposed at the four corners of the yoke 908, the coil 904, and the yoke 908, and the lens holder 903 is moved in the optical axis direction by electromagnetic force generated by energizing the coil 904. To move along.

Utility Model Registration No. 3179634

  In such a general lens drive device, when the coil is energized and the lens holding member is moved along the optical axis direction, the relative position between the coil held by the lens holding member and the fixed magnet is shifted. As the lens holding member moves away from the center position of the magnet, the electromagnetic force becomes weaker. On the other hand, when the lens holding member supported by the elastic member moves against the urging force of the elastic member, the pulling force from the elastic member becomes stronger as the lens holding member moves. For these reasons, in the vicinity of the moving end portion of the lens holding member, the thrust to the lens holding member is greatly reduced, and there is a problem that the linear relationship between the moving amount of the lens holding member and the energization amount of the coil is deteriorated.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a lens driving device in which thrust is hardly reduced even at a moving end portion of a lens holding member.

In order to solve this problem, a lens driving device of the present invention includes a cylindrical lens holding member that can hold a lens body, a biasing member that supports the lens holding member so as to be movable in the optical axis direction, A coil wound around and fixed to the outer periphery of the lens holding member, a magnet opposed to the coil, and a case capable of fixing the magnet and accommodating the lens holding member. The lens holding member moves in one direction against the urging force of the urging member, and the positional relationship between the coil and the magnet in the optical axis direction changes relatively. in, in accordance with the movement of the said one direction of said lens holding member, so that the distance between said coil and the magnet is reduced, is arranged to be inclined to the magnet, the coil is inclined in the same direction as the magnet It is characterized in that are wound in the lens holding member as.

According to this, as the lens driving device of the present invention moves in one direction, the electromagnetic force acting between the coil and the magnet becomes stronger. As a result, it is possible to prevent a reduction in thrust to the lens holding member in one direction as compared with the case where the magnet is not inclined and disposed. Accordingly, it is possible to provide a lens driving device in which the thrust is hardly reduced even at the moving end portion in one direction of the lens holding member. Further, the magnetic flux generated from the magnet can be made orthogonal or close to the coil. As a result, the magnetic flux generated from the magnet can be efficiently applied to the coil, and more thrust can be obtained.

  In the lens driving device of the present invention, the case is made of a metal material, and the case has an inner wall portion inclined along the side surface of the magnet, and the magnet is attached to the inner wall portion by an adhesive. It is characterized by being fixed.

  According to this, the accuracy of the inclination of the magnet can be obtained with the dimensional accuracy of the case made of a metal material. As a result, the accuracy of the assumed relative position between the magnet and the coil is improved, and the desired relationship between the movement amount of the lens holding member and the energization amount of the coil can be obtained.

  As the lens driving device of the present invention moves in one direction, the electromagnetic force acting between the coil and the magnet becomes stronger. As a result, it is possible to prevent a reduction in thrust to the lens holding member in one direction as compared with the case where the magnet is not inclined and disposed. Accordingly, it is possible to provide a lens driving device in which the thrust is hardly reduced even at the moving end portion in one direction of the lens holding member.

It is a disassembled perspective view explaining the lens drive device of 1st Embodiment of this invention. It is a perspective view explaining the lens drive device of a 1st embodiment of the present invention. FIGS. 3A and 3B are diagrams illustrating the lens driving device according to the first embodiment of the present invention, in which FIG. 3A is a top view when FIG. 2 is viewed from the Z1 side, and FIG. It is the front view seen from the side. 4A and 4B are diagrams illustrating the lens driving device according to the first embodiment of the present invention, in which FIG. 4A is a perspective view in which the case illustrated in FIG. 2 is omitted, and FIG. It is the perspective view which further omitted the spacer member shown in FIG. 5A and 5B are diagrams illustrating the lens driving device according to the first embodiment of the present invention, in which FIG. 5A is a bottom view when FIG. 2 is viewed from the Z2 side, and FIG. It is the bottom view which abbreviate | omitted the base member shown to (). FIGS. 6A and 6B are diagrams illustrating a lens holding member of the lens driving device according to the first embodiment of the present invention. FIG. 6A is a perspective view of the lens holding member, and FIG. It is the perspective view by which the coil was wound around the lens holding member shown to a). FIGS. 7A and 7B are diagrams illustrating a case of the lens driving device according to the first embodiment of the present invention, in which FIG. 7A is a perspective view of the case viewed from above, and FIG. It is the perspective view seen from the side. It is a figure explaining the case of the lens drive device concerning 1st Embodiment of this invention, Comprising: It is the bottom view which abbreviate | omitted the biasing member and the lens holding member from the bottom view shown in FIG.5 (b). 9A and 9B are diagrams illustrating the lens driving device according to the first embodiment of the present invention, in which FIG. 9A is a cross-sectional view taken along the line IX-IX shown in FIG. 3A, and FIG. It is an expanded sectional view of P part shown to Fig.9 (a). FIG. 10A is a diagram illustrating an urging member of the lens driving device according to the first embodiment of the present invention, and FIG. 10A is a top view of the upper leaf spring shown in FIG. 10 (b) is a top view of the lower leaf spring shown in FIG. 1 as viewed from the Z1 side. FIG. 11A is a perspective view of the base member, and FIG. 11B is a diagram illustrating the biasing member and the base member of the lens driving device according to the first embodiment of the present invention. It is a perspective view which shows the state by which the lower leaf | plate spring was mounted in the base member of 11 (a). It is a disassembled perspective view explaining the lens drive device of a prior art example.

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

[First Embodiment]
FIG. 1 is an exploded perspective view illustrating the lens driving device 101 according to the first embodiment of the present invention. FIG. 2 is a perspective view illustrating the lens driving device 101 according to the first embodiment of the present invention. 3A is a top view of the lens driving device 101 as viewed from the Z1 side in FIG. 2, and FIG. 3B is a front view of the lens driving device 101 as viewed from the Y2 side in FIG. 4A is a perspective view in which the case 4 of the lens driving device 101 shown in FIG. 2 is omitted, and FIG. 4B is a perspective view in which the spacer member S9 shown in FIG. 4A is further omitted. is there. 5A is a bottom view of the lens driving device 101 as viewed from the Z2 side in FIG. 2, and FIG. 5B is a bottom view in which the base member 8 shown in FIG. 5A is omitted.

  The lens driving device 101 according to the first embodiment of the present invention has a rectangular parallelepiped shape as shown in FIGS. 2, 3 and 5A. As shown in FIG. 1, a lens body (not shown) ), A coil 3 wound around and fixed to the outer periphery of the lens holding member 2, a case 4 capable of housing the lens holding member 2, and a coil 3 disposed opposite to each other. And a biasing member 6 that supports the lens holding member 2 so as to be movable in the optical axis direction. In addition, in the first embodiment of the present invention, the lens driving device 101 includes a base member 8 disposed below the lens holding member 2 (Z2 direction shown in FIG. 4), as shown in FIG. 4A, and a spacer member S9 disposed above the lens holding member 2 (Z1 direction shown in FIG. 4).

  Further, as shown in FIG. 4B, the urging member 6 includes an upper leaf spring 6A fixed to the upper portion of the lens holding member 2, and a lower portion of the lens holding member 2 as shown in FIG. The lower plate spring 6 </ b> C and the lower plate spring 6 </ b> E that are fixed to each other are configured to support the lens holding member 2. In the first embodiment of the present invention, the urging member 6 urges the lens holding member 2 downward.

  The lens driving device 101 holds a lens body (not shown) on the lens holding member 2 and is mounted on a substrate (not shown) on which an imaging element is mounted. Then, in order to adjust the focal length by driving the lens held by the lens body in the optical axis direction (Z direction shown in FIG. 2), the lens driving device 101 is generated when current is supplied from the power source to the coil 3. The lens holding member 2 is moved in an upward direction (Z1 direction), which is one direction, against the urging force of the urging member 6 with respect to the image pickup device by electromagnetic force.

  Next, each component will be described in detail. First, the lens holding member 2 of the lens driving device 101 will be described. 6A and 6B are diagrams for explaining the lens holding member 2. FIG. 6A is a perspective view of the lens holding member 2, and FIG. 6B is a lens holding member shown in FIG. 2 is a perspective view in which a coil 3 is wound around 2. FIG.

  The lens holding member 2 of the lens driving device 101 is made of a liquid crystal polymer (LCP, Liquid Crystal Polymer), which is one of synthetic resins, and is formed in a cylindrical shape as shown in FIG. And a cylindrical portion 12 having an inner peripheral surface, and a flange portion 32 projecting radially outward from the outer peripheral surface of the lower end (Z2 side shown in FIG. 4) of the cylindrical portion 12. And the lens holding member 2 is arrange | positioned above the base member 8 (Z1 direction shown in FIG. 4), as shown in FIG.

  As shown in FIG. 6, the cylindrical portion 12 of the lens holding member 2 has a female screw portion 12n formed on its inner peripheral surface, and a lens body (not shown) is mounted and held on the female screw portion 12n. Moreover, as shown in FIG. 6, the coil support part 12j which supports the coil 3 from an inner side is equally provided in four places (in FIG. 6, two places are shown in figure) on the outer peripheral surface of the cylinder part 12, On one end side (upper end side) of the coil support portion 12j, a flange portion 12h that faces the flange portion 32 and protrudes radially outward is formed.

  Further, as shown in FIG. 6, two pedestal portions 12d are formed on the outer peripheral surface of the cylindrical portion 12 further above the flange portion 12h so as to face diagonally. When the lens driving device 101 is assembled, as shown in FIG. 4B, two pedestal portions 12d and the upper leaf spring 6A (described later) face each other (in the X direction shown in FIG. 4B). The first part 16) is fixed with an adhesive.

Further, on the bottom surface of the lens holding member 2 on the collar portion 32 side, as shown in FIG. 5 (b), a cylindrical shape protruding downward (in FIG. 5 (b), in the Z2 direction shown in FIG. 6 in front of the paper surface). The projecting portions 12t are provided at four places (two projecting portions 12t ₁ and two projecting portions 12t ₂ ). When the lens driving device 101 is assembled, as shown in FIG. 5B, the two projecting portions 12t _{1 are} caulked to engage with the lower leaf spring 6C (a third portion 36 described later). At the same time, the two protruding portions 12t _{2 are} caulked to engage with the lower leaf spring 6E (a third portion 36 described later).

  Further, as shown in FIG. 5B, two prism-like binding portions 12 k protruding downward are provided on the bottom surface of the lens holding member 2. Each of the coil end portions of the coil 3 is wound around the binding portion 12k and soldered to the two lower leaf springs 6C and 6E. In FIG. 5B, the solder HD obtained by soldering two coil ends to the lower leaf spring 6C and the lower leaf spring 6E is schematically shown by cross hatching surrounded by a broken line.

  Next, the coil 3 of the lens driving device 101 will be described. The coil 3 is made of a metal wire having an insulating coating (coating) on the outer periphery, and is wound around the outer periphery of the lens holding member 2 as shown in FIG. It is formed in an octagonal ring. In that case, the coil 3 is arrange | positioned between the collar part 12h and the collar part 32, and is supported and fixed to the coil support part 12j from the inner side, as shown in FIG.6 (b). The coil 3 has a shape in which a metal wire is wound and bundled. However, in FIG. 1, FIG. 4, and FIG.

  The coil 3 is electrically conductive at both ends of the wound metal wire, and as described above, each of the coil ends has two lower ends as shown in FIG. The side plate spring 6C and the lower plate spring 6E are soldered and electrically connected.

  Next, the case 4 of the lens driving device 101 will be described. FIG. 7A is a perspective view of the case 4 viewed from above, and FIG. 7B is a perspective view of the case 4 viewed from below. FIG. 8 is a bottom view in which the biasing member 6 (the lower leaf spring 6C and the lower leaf spring 6E) and the lens holding member 2 are further omitted from the bottom view shown in FIG. FIG. 9 is a diagram illustrating the lens driving device 101 according to the first embodiment of the present invention. FIG. 9A is a cross-sectional view taken along line IX-IX shown in FIG. (B) is an expanded sectional view of P part shown to Fig.9 (a). FIG. 9 shows a state in which the lens holding member 2 is urged by the urging member 6 and is positioned at the lower limit.

  The case 4 is manufactured by bending, drawing, etc. using a soft magnetic metal plate such as iron, and the outer shape as shown in FIG. 7 is formed in a box shape, as shown in FIG. It has a substantially rectangular shape as shown (in plan view). As shown in FIG. 7, the case 4 includes a cylindrical outer plate 4A, and a flat plate-like upper plate portion 4B provided continuously with the upper end (Z1 side shown in FIG. 1) of the outer periphery 4A, And four inner yokes 4C extending downward (Z2 direction shown in FIG. 7) from a part of the opening 4k formed in the upper plate portion 4B. 2, the case 4 covers the lens holding member 2, the coil 3, the magnet 5, the biasing member 6 (upper leaf spring 6A, lower leaf spring 6C, lower leaf spring 6E) and the spacer member S9. Thus, these members are accommodated, engaged with the base member 8, and integrated with the base member 8.

  When the lens driving device 101 is assembled, as shown in FIG. 8, the magnets 5 are disposed between the four corners of the outer peripheral portion 4A and the inner yoke 4C, and the coil 3 A magnetic circuit is formed by the magnet 5 and the case 4 (the outer peripheral portion 4A, the upper plate portion 4B, and the inner yoke 4C). That is, the case 4 functions as a yoke for the magnet 5 and contributes to an improvement in thrust for moving the lens holding member 2 in the optical axis direction.

  Further, as shown in FIG. 3B, the outer peripheral portion 4A of the case 4 has an inclined portion whose upper side is inclined toward the center side (the lens holding member 2 side), as shown in FIG. Further, since the metal plate is processed, the inner wall portion 4w of the inclined portion is also inclined. As shown in FIG. 9, the inner wall 4w is formed along the side surface of the magnet 5 that is desired to be inclined, and the magnet 5 is fixed to the inner wall 4w by an adhesive. That is, by fixing the magnet 5 to the inner wall portion 4w of the case 4 with an adhesive, the accuracy of the inclination of the magnet 5 can be obtained with the dimensional accuracy (inclination accuracy) of the case 4 made of a metal plate. .

  Next, the magnet 5 of the lens driving device 101 will be described. For example, four samarium cobalt magnets are used as the magnet 5, and are arranged and fixed to the four corners of the outer peripheral portion 4 </ b> A of the case 4 so as to face the coil 3 as shown in FIG. 8. Further, the magnet 5 is formed in a trapezoidal columnar shape in plan view as shown in FIG. 1 and intersects the optical axis direction (Z direction shown in FIG. 9) as shown in FIG. The cross-sectional shape in the direction to be fixed has a certain shape. The magnet 5 is magnetized in a linear direction perpendicular to the short side surface and the long side surface. In other words, the magnet 5 is magnetized so as to have different magnetic poles on the inner side facing the coil 3 and on the outer side (see FIG. 8) opposite to the inner side.

  Thereby, the productivity of the magnet 5 is good, and the magnetic flux generated from the magnet 5 becomes stable. The “crossing direction” referred to here is a direction inclined by 4 ° with respect to the XY plane orthogonal to the optical axis direction in the first embodiment of the present invention. Therefore, in the first embodiment, the upper part of the magnet 5 is disposed in a state inclined by 4 ° in a direction closer to the cylindrical part 12 of the lens holding member 2 than the lower part. The inclination angle of the magnet 5 is not limited to 4 °, and can be suitably set in the range of 2 ° to 6 °. By tilting the magnet 5 at such an angle, it is possible to appropriately suppress a reduction in thrust even when the lens holding member 2 moves upward.

  As described above, since the lens holding member 2 and the coil 3, the case 4 and the magnet 5 are respectively arranged, the lens driving device 101 is an electromagnetic generated by a current flowing from the power source to the coil 3. The force causes a thrust to act on the coil 3 so that the lens holding member 2 moves in one direction against the urging force of the urging member 6. At this time, the positional relationship between the central portion of the coil 3 in the optical axis direction and the central portion of the magnet 5 in the optical axis direction relatively changes.

  In the lens driving device 101, as shown in FIG. 9B, the magnet 5 is inclined and disposed, so that the coil 3 is moved in one direction (upward) as the lens holding member 2 moves. An interval between the side surface and the inclined surface of the magnet 5 is configured to be small. Thereby, the electromagnetic force which acts between the coil 3 and the magnet 5 becomes strong as it moves to one direction. As a result, it is possible to prevent a reduction in thrust to the lens holding member 2 in one direction as compared with the case where the magnet 5 is not inclined and disposed. Therefore, it is possible to provide the lens driving device 101 in which the thrust is hardly reduced even at the moving end portion in one direction of the lens holding member 2. In the first embodiment of the present invention, since the urging member 6 urges the lens holding member 2 downward (Z1 direction shown in FIG. 9), the urging force of the urging member 6 is resisted. The one direction of movement is upward (Z1 direction shown in FIG. 9).

  In the first embodiment of the present invention, as described above, since the magnet 5 is fixed to the inner wall 4w of the case 4, the dimensional accuracy (inclination accuracy) of the inner wall 4w of the case 4 made of metal material. ), The accuracy of the inclination of the magnet 5 can be obtained. As a result, the assumed accuracy of the relative position between the magnet 5 and the coil 3 is improved, and the desired relationship between the amount of movement of the lens holding member 2 and the amount of energization of the coil 3 can be obtained.

  Next, the spacer member S9 of the lens driving device 101 will be described. The spacer member S9 is a frame that uses a synthetic resin such as polybutylene terephthalate (PBT) and has a substantially rectangular opening S9k at the center as shown in FIG. Further, as shown in FIG. 4A, the spacer member S9 is disposed above the upper leaf spring 6A. As shown in FIG. 9, the spacer member S9 and the magnet 5 constitute the upper leaf spring 6A. A part (second part 26 described later) is sandwiched.

  Next, the urging member 6 of the lens driving device 101 will be described. FIG. 10 is a diagram for explaining the biasing member 6, FIG. 10 (a) is a top view of the upper leaf spring 6 </ b> A shown in FIG. 1 as viewed from the Z <b> 1 side, and FIG. 6 is a top view of the lower leaf spring 6C and the lower leaf spring 6E shown in FIG. 11A and 11B are diagrams illustrating the urging member 6 and the base member 8, in which FIG. 11A is a perspective view of the base member 8, and FIG. 11B is a base of FIG. 6 is a perspective view showing a state in which a lower leaf spring 6C and a lower leaf spring 6E are placed on a member 8. FIG.

  The urging member 6 of the lens driving device 101 is made of a metal plate mainly made of a copper alloy. As shown in FIG. 4B, the urging member 6 is formed from the inner peripheral surface of the cylindrical portion 12 of the lens holding member 2. Has an opening having a large diameter, and an upper leaf spring 6A disposed between the lens holding member 2 and the spacer member S9, and two lower plates disposed between the lens holding member 2 and the base member 8. A side leaf spring 6C and a lower leaf spring 6E are included. Then, each of the lens holding member 2 and the biasing member 6 (upper leaf spring 6A, lower leaf spring 6C, lower leaf spring 6E) is engaged, and the lens holding member 2 moves in the optical axis direction (Z direction shown in FIG. 2). The lens holding member 2 is supported so as to be movable. Since the lower leaf spring 6C and the lower leaf spring 6E (two leaf springs) are electrically connected to the coil 3 by solder HD as shown in FIG. 5B, a power feeding member for the coil 3 is used. It also has a function as

  As shown in FIG. 10A, the upper leaf spring 6 </ b> A of the urging member 6 has a substantially rectangular outer shape, two first portions 16 fixed to the lens holding member 2, and a magnet. 5 and the spacer member S9, the four second portions 26 fixed between the first member 16 and the spacer member S9, the four elastic arm portions 66a located between the first portion 16 and the second portion 26, and the two second portions 26a. And a crosspiece 76 that connects the two portions 26 to each other.

  When the upper leaf spring 6A is incorporated in the lens driving device 101, the first portion 16 is placed on the pedestal 12d of the lens holding member 2 as shown in FIG. By fixing 16 and the pedestal portion 12d with an adhesive, one side of the upper leaf spring 6A is fixed to the lens holding member 2. Further, the second portion 26 comes into contact with the upper surface of the magnet 5 (see FIG. 4B) and is pressed by the case 4 through the spacer member S9, so that the other side of the upper leaf spring 6A is fixed. .

  Further, as shown in FIG. 10A, the upper leaf spring 6 </ b> A has a substantially line-symmetric shape, and is connected to the lens holding member 2 at two equal positions of the first portion 16. In addition, the second portion 26 is connected to the case 4 (magnet 5) at four equal positions. Thereby, the lens holding member 2 can be supported with good balance.

  As shown in FIG. 10B, the lower leaf spring 6C and the lower leaf spring 6E of the urging member 6 have a substantially rectangular outer shape and a semicircular inner shape, and the lens holding member 2 The four third portions 36 engaged with the base member 8, the four fourth portions 46 engaged with the base member 8, and the four elastic portions located between the third portion 36 and the fourth portion 46. The arm portion 66c and the elastic arm portion 66e, a first connecting portion 86 that connects two third portions 36, and a second connecting portion 96 that connects two fourth portions 46, respectively. ing.

When the lower leaf spring 6C and the lower leaf spring 6E are incorporated in the lens driving device 101, as shown in FIG. 5B, the two protruding portions 12t ₁ (12t) of the lens holding member 2 are provided. Is inserted and fitted into a through hole 36k provided in the third portion 36 of the lower leaf spring 6C shown in FIG. 10B, and the two protruding portions 12t ₂ (12t) of the lens holding member 2 are fitted. Is inserted through and fitted into a through hole 36k provided in the third portion 36 of the lower leaf spring 6E shown in FIG. Accordingly, one side of the lower leaf spring 6C and the lower leaf spring 6E is positioned on the lens holding member 2 and fixed to the lens holding member 2. At this time, the convex portions 12t (12t ₁ , 12t ₂ ) of the lens holding member 2 are heat caulked to more securely fix the lower leaf spring 6C and the lower leaf spring 6E to the lens holding member 2. ing.

On the other hand, through-holes 46m (see FIG. 10B) provided in the fourth portions 46 of the lower leaf spring 6C and the lower leaf spring 6E are formed on the base member 8 described later, as shown in FIG. The protrusions 18t (18t ₁ and 18t ₂ ) provided on the upper surface are inserted and fitted. Accordingly, the other side of the lower leaf spring 6 </ b> C and the lower leaf spring 6 </ b> E is positioned on the base member 8 and is fixed to the base member 8.

  Further, as shown in FIG. 10B, the lower leaf spring 6C and the lower leaf spring 6E are configured in a substantially line-symmetric shape, and the four portions of the third portion 36 with respect to the lens holding member 2 are formed. In addition to being connected at equal positions, the base member 8 is connected at four equal positions of the fourth portion 46. Thereby, the lens holding member 2 can be supported with good balance. Accordingly, the urging member 6 configured as described above supports the lens holding member 2 so as to be movable in the optical axis direction.

Finally, the base member 8 of the lens driving device 101 will be described. The base member 8 is manufactured by injection molding using the same synthetic resin material as the lens holding member 2 such as liquid crystal polymer (LCP). As shown in FIG. And is formed in an annular shape having a circular opening 8k at the center. Further, as shown in FIG. 11A, four projecting portions 18 t (two projecting portions 18 t ₁ and two projecting portions 18 t ₂ ) projecting upward are formed on the upper surface of the base member 8. It is provided at the four corners. As described above, as shown in FIG. 11 (b), the protruding portion 18t is inserted into the through hole 46m (see FIG. 10 (b)) of the lower leaf spring 6C and the lower leaf spring 6E. Combined. At this time, the caulking portion 18t of the base member 8 is heat caulked to more reliably fix the lower leaf spring 6C and the lower leaf spring 6E to the base member 8.

  Further, as shown in FIG. 11A, the base member 8 has two terminals T7 (terminal T7C and terminal T7E) made of a metal plate using a material such as copper, iron, or an alloy containing them as a main component. However, it is insert-molded and embedded. Each of the two electrically insulated terminals T7 is electrically connected to an electrode land on a substrate on which an imaging element (not shown) is mounted, and can supply power from the electrode land on this substrate. .

  In addition, one terminal T7C of the terminal T7 is electrically connected to the connection portion T7d shown in FIG. 11A at the through hole 46s portion of the lower leaf spring 6C shown in FIG. The other terminal T7E of T7 is electrically connected to the connection portion T7f shown in FIG. 11A at the portion of the through hole 46t of the lower leaf spring 6E shown in FIG. Thereby, an electric current can be sent through the coil 3 from the terminal T7C and the terminal T7E via the lower leaf spring 6C and the lower leaf spring 6E. The lower leaf springs (6C, 6E) and the terminals T7 (T7C, T7E) are easily connected by soldering or the like.

  Although not shown in detail in the base member 8, a connecting member 57 made of a metal plate using a material such as copper, iron, or an alloy containing them as a main component is also inserted in the same manner as the terminal T7. The part of the connecting member 57 is partially exposed at the four corners of the case 4 as shown in FIG. After the inner wall of the outer peripheral portion 4A of the case 4 and the outer peripheral side surface of the base member 8 are combined and positioned, four joints between the connecting member 57 of the base member 8 and the four corners of the case 4 are welded, 4 is fixed to the base member 8.

  Finally, the operation of the lens driving device 101 will be briefly described. First, in the lens driving device 101, since both ends of the coil 3 are electrically connected to the terminal T7C and the terminal T7E via the lower leaf spring 6C and the lower leaf spring 6E, the coil is connected from the terminal T7C and the terminal T7E to the coil. 3 can be made to pass current. On the other hand, the magnetic flux from the magnet 5 emits the magnet 5, passes through the coil 3, travels toward the inner yoke 4C of the case 4, and returns from the outer peripheral portion 4A to the magnet 5 via the upper plate portion 4B of the case 4. It has become.

  From this initial state (the state shown in FIG. 9), when a current is passed through the coil 3 from the terminal T7E side, the coil 3 follows the Fleming's left-hand rule from the Z2 direction, which is the optical axis direction, to the Z1 direction, that is, in one direction. Electromagnetic force is generated. Since the urging member 6 urges in the other direction from the Z1 direction, which is the optical axis direction, to the Z2 direction, the lens holding member 2 moves in one direction against the urging force. At that time, the coil 3 moves from the position of the solid line coil 3 shown in FIG. 9B to the position of the two-dot chain line coil 3 shown in FIG. The distance between the surface and the surface gradually decreases. As a result, the biasing force in the other direction (Z2 direction) received by the lens holding member 2 increases as it moves in one direction (Z1 direction), but the electromagnetic force acting between the coil 3 and the magnet 5 increases. . For this reason, the thrust of the lens holding member 2 moves without decreasing even at the moving end in one direction.

  The effects of the lens driving device 101 according to the first embodiment of the present invention configured as described above will be described below.

  The lens driving device 101 according to the first embodiment of the present invention energizes the coil 3 and the lens holding member 2 moves in one direction against the urging force of the urging member 6. Even when the position in the optical axis direction changes, the magnet 5 is inclined and arranged so that the distance between the coil 3 and the magnet 5 is reduced in one direction. For this reason, the electromagnetic force which acts between the coil 3 and the magnet 5 becomes strong as it moves to one direction. As a result, it is possible to prevent a reduction in thrust to the lens holding member 2 in one direction as compared with the case where the magnet 5 is not inclined and disposed. Therefore, it is possible to provide the lens driving device 101 in which the thrust is hardly reduced even at the moving end portion in one direction of the lens holding member 2.

  In addition, since the magnet 5 is fixed to the inner wall portion 4w of the case 4 inclined along the side surface of the magnet 5 with an adhesive, the accuracy of the inclination of the magnet 5 with the dimensional accuracy of the case 4 made of a metal material. Can be issued. As a result, the assumed accuracy of the relative position between the magnet 5 and the coil 3 is improved, and the desired relationship between the amount of movement of the lens holding member 2 and the amount of energization of the coil 3 can be obtained.

  In addition, this invention is not limited to the said embodiment, For example, it can deform | transform and implement as follows, These embodiments also belong to the technical scope of this invention.

<Modification 1>
In the first embodiment, only the magnet 5 is tilted toward the coil 3. However, the present invention is not limited to this. For example, the lens holding member 2 is tilted in the same direction as the magnet 5. You may make it wind. Thereby, the magnetic flux generated from the magnet 5 can be made orthogonal to or closer to the orthogonal to the coil 3. As a result, the magnetic flux generated from the magnet 5 can be efficiently applied to the coil 3, and more thrust can be obtained.

<Modification 2>
In the first embodiment, the magnet 5 having a constant cross-sectional shape in the direction intersecting the optical axis direction is used, and the magnet 5 is arranged inclined with respect to the optical axis direction. It is not limited. For example, a magnet formed so that its cross-sectional shape gradually changes with respect to the optical axis direction is used, and the magnet is arranged so that the surface of the magnet tends to be small so that the gap between the magnet and the coil 3 is small. You may make it do.

  The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the scope of the object of the present invention.

2 Lens holding member 3 Coil 4 Case 4w Inner wall 5 Magnet 6 Energizing member 101 Lens driving device

Claims (2)

A cylindrical lens holding member capable of holding a lens body, a biasing member that supports the lens holding member so as to be movable in the optical axis direction, a coil wound around and fixed to the outer periphery of the lens holding member, A magnet disposed opposite to the coil, and a case for fixing the magnet and accommodating the lens holding member,
By passing a current through the coil, the lens holding member moves in one direction against the biasing force of the biasing member, and the positional relationship between the coil and the magnet in the optical axis direction changes relatively. In the lens driving device
With the movement of the lens holding member in the one direction, the magnet is inclined and arranged so that the distance between the coil and the magnet is reduced ,
The lens driving device , wherein the coil is wound around the lens holding member so as to be inclined in the same direction as the magnet . The case is made of a metal material,
The case is formed with an inner wall portion inclined along the side surface of the magnet,
The lens driving device according to claim 1, wherein the magnet is fixed to the inner wall portion with an adhesive.