JP6006044B2 - Lens drive device - Google Patents

Description

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

  2. Description of the Related Art Conventionally, a lens driving device that drives a photographing lens of a camera mounted on a mobile phone or the like is known (for example, see Patent Document 1). The lens driving device described in Patent Literature 1 includes a lens holder that holds a lens barrel, a resin base on which the lens holder is mounted, and a resin cover that covers the lens holder.

  In the lens driving device described in Patent Document 1, triangular columnar portions that rise in the optical axis direction of the lens are formed at the four corners of the base. A magnetic member formed in a rectangular flat plate shape is fixed to a side surface facing the inside of the columnar portion. First and second driving coils for driving the lens holder in the optical axis direction are wound around the columnar portion to which the magnetic member is fixed. The first driving coil and the second driving coil are wound around the columnar portion so as to overlap in the optical axis direction. Further, the winding direction of the second driving coil is opposite to the winding direction of the first driving coil.

  In the lens driving device described in Patent Document 1, a driving magnet for driving the lens holder in the optical axis direction together with the first and second driving coils is fixed to the outer peripheral surface of the lens holder. The drive magnet is formed in a rectangular flat plate shape. The driving magnet is fixed to the outer peripheral surface of the lens holder so as to face each of the four first and second driving coils. That is, four drive magnets are fixed to the outer peripheral surface of the lens holder. The driving magnet is magnetized so that the magnetic pole on the surface facing the first driving coil is different from the magnetic pole on the surface facing the second driving coil.

JP 2011-39481 A

  In the lens driving device described in Patent Document 1, the first driving coil and the second driving coil having different winding directions are directly wound around the columnar portion to which the magnetic member is fixed. Therefore, when the first drive coil and the second drive coil are configured by a single conductor, the work for changing the winding direction of the conductor is complicated. Further, when the first drive coil and the second drive coil are configured by two conductive wires, it is necessary to process the end portions of the two conductive wires. Processing becomes complicated. That is, in the lens driving device described in Patent Document 1, the winding operation of the first and second driving coils becomes complicated.

  In the lens driving device described in Patent Document 1, the first and second driving coils are wound a predetermined number of times around a columnar portion to which a magnetic member is fixed in order to ensure the driving force of the lens holder. However, since the columnar part is formed in the shape of a triangular prism, the length of the conducting wire constituting the first and second drive coils tends to be long. When the length of the conducting wire constituting the first and second driving coils is increased, the power consumption of the first and second driving coils is increased, and the power consumption of the lens driving device is increased.

  Accordingly, an object of the present invention is to easily perform the winding operation of the first driving coil and the second driving coil which are arranged so as to overlap in the optical axis direction of the lens and are wound in opposite directions. And it is providing the lens drive device which can reduce the power consumption in the 1st drive coil and the 2nd drive coil.

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 accommodates the movable body, and moves the movable body in the optical axis direction. A driving mechanism for driving ; a guide ball disposed between the movable body and the fixed body for guiding the movable body in the optical axis direction; and a position detection mechanism for detecting the position of the movable body in the optical axis direction. And a lens driving device formed so that the shape when viewed from the optical axis direction is a substantially square shape, wherein the driving mechanism includes a driving magnet fixed to one of the movable body and the fixed body, A magnetic member fixed to the other of the movable body or the fixed body, a bobbin formed of an insulating material and covering at least a part of a side surface of the magnetic member, and wound around the bobbin so as to face the driving magnet and in the optical axis direction The first wheel drive arranged to overlap Rutotomoni a use coil and the second drive coil, when viewed in the optical axis direction, are arranged in one corner of the lens driving device, the driving magnets, of the drive magnet, the first drive The magnetic pole on the surface facing the coil for driving and the magnetic pole on the surface facing the second driving coil of the driving magnet are magnetized to be different from each other, and the winding direction of the second driving coil is 1 is a direction opposite to the winding direction of the driving coil, the first winding part of the magnetic member is a part around which the first driving coil is wound via the bobbin, and the bobbin of the magnetic member The second winding portion, which is a portion around which the second driving coil is wound, is a flat plate shape in which the first driving coil and the opposing direction of the second driving coil and the driving magnet are in the thickness direction. The first drive coil is formed in a substantially cylindrical shape along the outer peripheral surface of the first winding part. The second drive coil, is formed in a substantially tubular shape along the outer circumferential surface of the second winding portion, the guide ball when viewed in the optical axis direction, the lens except one place the drive mechanism is arranged Of the remaining three corners of the drive device, two positions are arranged on the diagonal line, and the position detection mechanism has three positions where the drive mechanism and the guide ball are arranged when viewed from the optical axis direction. The movable body is arranged at the remaining one of the four corners of the lens driving device except the movable body and the guide ball, and the stationary body and the guide ball due to the magnetic attractive force generated between the driving magnet and the magnetic member. It is biased in the direction in which the ball comes into contact .

  In the lens driving device of the present invention, the first driving coil and the second driving coil are wound around a bobbin that covers at least a part of the side surface of the magnetic member. Therefore, in the present invention, even if the winding direction of the first driving coil and the winding direction of the second driving coil are opposite directions, the first driving coil and the second driving are utilized using the bobbin. It is possible to easily change the winding direction of the conductive wire constituting the coil for use. Therefore, in the present invention, the winding operation of the first drive coil and the second drive coil can be easily performed.

In the lens driving device of the present invention, the first winding portion and the second winding portion are flat plates whose thickness direction is the first driving coil and the opposing direction of the second driving coil and the driving magnet. And the first driving coil is formed in a substantially cylindrical shape along the outer peripheral surface of the first winding portion, and the second driving coil is the outer peripheral surface of the second winding portion. It is formed in a substantially cylindrical shape so as to follow. Therefore, in order to secure the driving force of the driving mechanism, even if the first driving coil and the second driving coil are wound around the magnetic member a predetermined number of times via the bobbin, the first driving coil and the second driving coil It becomes possible to shorten the length of the conducting wire constituting the driving coil. As a result, in the present invention, it is possible to reduce power consumption in the first drive coil and the second drive coil. In the present invention, the lens driving device includes a guide ball that is disposed between the movable body and the fixed body and guides the movable body in the optical axis direction, and the movable body is interposed between the driving magnet and the magnetic member. Due to the generated magnetic attractive force, the movable body and the guide ball are in contact with each other, and the fixed body and the guide ball are urged in the contact direction. Therefore, it becomes possible to suppress the shakiness of the movable body when moving in the optical axis direction. In addition, since it becomes possible to reduce the sliding resistance when the movable body moves in the optical axis direction, it is possible to reduce the driving force of the drive mechanism necessary for moving the movable body in the optical axis direction. become. In the present invention, the lens driving device includes a position detection mechanism for detecting the position of the movable body in the optical axis direction, and is formed so that the shape when viewed from the optical axis direction is a substantially square shape. The driving mechanism is disposed at one of the four corners of the lens driving device when viewed from the optical axis direction, and the guide ball is disposed at one position where the driving mechanism is disposed when viewed from the optical axis direction. Except for the remaining three corners of the four corners of the lens driving device, two positions are arranged on the diagonal line, and the position detection mechanism has a driving mechanism and a guide ball arranged when viewed from the optical axis direction. They are arranged at the remaining one of the four corners of the lens driving device excluding the place. That is, since the driving mechanism, the guide ball, and the position detection mechanism are arranged at the corners of the lens driving device that is likely to become a dead space, the lens driving device can be downsized in the radial direction of the lens. Alternatively, the lens diameter can be increased without increasing the size of the lens driving device in the lens radial direction.

  In the present invention, the third winding portion of the bobbin where the first driving coil is wound and the fourth winding portion of the bobbin where the second driving coil is wound are The first drive coil and the second drive coil and the drive magnet are preferably constituted by two side surfaces arranged on both sides in a direction orthogonal to the facing direction and the optical axis direction. That is, it is preferable that the third winding portion and the fourth winding portion are not formed with side surfaces in the opposing direction of the first driving coil and the second driving coil and the driving magnet. If comprised in this way, it will become possible to shorten the length of the conducting wire which comprises the 1st drive coil and the 2nd drive coil, As a result, in the 1st drive coil and the 2nd drive coil, It becomes possible to further reduce power consumption. Also, with this configuration, even when the first driving coil and the second driving coil are wound around the magnetic member via the bobbin, the distance between the driving magnet and the magnetic member can be reduced. . Therefore, it is possible to increase the density of the magnetic flux passing through the first driving coil and the second driving coil, and as a result, it is possible to increase the driving force of the driving mechanism.

  In the present invention, on both ends of the bobbin in the optical axis direction, conductive wire end binding pins for connecting the end portions of the conductive wires constituting the first drive coil and the second drive coil are formed. Between the third winding part of the bobbin where the first driving coil is wound and the fourth winding part of the bobbin where the second driving coil is wound. The winding direction changing pin for changing the winding direction of the conducting wire is preferably formed. If comprised in this way, since the end part of a conducting wire can be processed using the conducting wire end part binding pin, the process of the end part of a conducting wire becomes easy. Moreover, if comprised in this way, since the winding direction of conducting wire can be changed using the pin for winding direction change, the change of the winding direction of conducting wire becomes easy.

  In the present invention, the length of the magnetic member in the optical axis direction is longer than the length of the driving magnet in the optical axis direction, and both end sides of the magnetic member in the optical axis direction are the ends of the driving magnet in the optical axis direction. It is preferable to protrude outward in the optical axis direction from both ends. The length of the magnetic member in the optical axis direction is shorter than the length of the driving magnet in the optical axis direction, and both ends of the magnetic member in the optical axis direction are closer to the optical axis direction than both ends of the driving magnet in the optical axis direction. When arranged inside, when no current is supplied to the first drive coil and the second drive coil, the magnetic attractive force toward the center of the magnetic member in the optical axis direction is applied to the drive magnet. It becomes easy to work. Therefore, in this case, the driving force of the driving mechanism necessary for moving the movable body to a predetermined position in the optical axis direction must be increased. On the other hand, the length of the magnetic member in the optical axis direction is longer than the length of the driving magnet in the optical axis direction, and both end sides of the magnetic member in the optical axis direction are longer than both ends of the driving magnet in the optical axis direction. If it also protrudes to the outside in the optical axis direction, the magnetic attractive force toward the center of the magnetic member in the optical axis direction is less likely to act on the driving magnet. Therefore, it is possible to reduce the driving force of the driving mechanism necessary for moving the movable body to a predetermined position in the optical axis direction.

  In the present invention, it is preferable that the drive magnet is fixed to the movable body, the magnetic member is fixed to the fixed body, and the fixed body is formed of a nonmagnetic material. If comprised in this way, the process of a drive coil will become easy compared with the case where the magnetic member is being fixed to the movable body (namely, the case where the drive coil is attached to the movable body). Also, with this configuration, since the fixed body is made of a nonmagnetic material, the driving force of the drive mechanism is reduced by the magnetic attractive force generated between the driving magnet fixed to the movable body and the fixed body. Can be prevented.

  As described above, in the lens driving device of the present invention, the winding operation of the first driving coil and the second driving coil that are arranged so as to overlap in the optical axis direction of the lens and are wound in opposite directions to each other can be easily performed. This makes it possible to reduce power consumption in the first driving coil and the second driving coil.

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 state which removed the cover member and the holder from the lens drive device shown in FIG. FIG. 3 is a perspective view of a drive magnet, a magnetic member, and a bobbin shown in FIG. 2. It is a figure for demonstrating the state of the magnet for a drive, and the state of a magnetic member when the movable body shown in FIG. 2 moves to an optical axis direction, and its front and back.

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

(Entire 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 lens driving device 1 shown in FIG. 1 with the cover member 13 and the holder 15 removed.

  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, the Z direction is the up-down direction, the X1 direction side is the “right” side, the X2 direction side is the “left” side, the Y1 direction side is the “front” side, and the Y2 direction The side is the “rear (back)” side, the Z1 direction side is the “upper” side, and the Z2 direction side is the “lower” side. In addition, a plane composed of the X direction and the Y direction is an “XY plane”, a plane composed of the Y direction and the Z direction is “YZ plane”, and a plane composed of the Z direction and the X direction is “ZX”. Plane ”.

  The lens driving device 1 according to the present 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 flat rectangular column shape as a whole. Specifically, the lens driving device 1 is formed so that the shape of the lens 2 for photographing when viewed from the direction of the optical axis L (optical axis direction) is substantially square. Moreover, the four side surfaces of the lens driving device 1 are substantially parallel to the YZ plane or the ZX plane.

  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, an imaging element (not shown) is arranged on the lower end side of the lens driving device 1, 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).

  The lens driving device 1 includes a movable body 4 that holds the lens 2 and is movable in the optical axis direction, a fixed body 5 that houses the movable body 4, and a drive mechanism 6 that drives the movable body 4 in the optical axis direction. And. The lens driving device 1 also includes three guide balls 7 for guiding the movable body 4 in the optical axis direction, and guides the movable body 4 together with the guide balls 7 and is movable with the optical axis direction as the axial direction. Three guide balls 8 for preventing the body 4 from rotating are provided. Furthermore, the lens driving device 1 includes a position detection mechanism 9 for detecting the position of the movable body 4 in the optical axis direction.

  The lens 2 is fixed to the inner peripheral side of a lens holder 11 formed in a substantially cylindrical shape. The movable body 4 includes a sleeve 12 to which the lens holder 11 is fixed. The sleeve 12 is made of resin. The sleeve 12 is formed in a substantially cylindrical shape. A lens holder 11 is fixed to the inner peripheral surface of the sleeve 12. In FIG. 2, the lens 2 is not shown.

  Two projecting portions 12 a and 12 b projecting toward the outer periphery of the sleeve 12 are formed on the outer periphery of the sleeve 12. The protrusion 12a is formed to protrude to the left rear side, and the protrusion 12b is formed to protrude to the right front side. Further, the protruding portions 12a and 12b are formed over substantially the entire area of the sleeve 12 in the vertical direction. The protrusion 12a is formed with a recess 12c in which a part of the guide ball 7 is disposed, and the protrusion 12b is formed with a recess 12d in which a part of the guide ball 8 is disposed.

  The recesses 12c and 12d are formed on the right rear side of the protrusions 12a and 12b so as to be recessed toward the left front side. The recess 12c is composed of a side surface 12e substantially parallel to the ZX plane and a side surface 12f substantially parallel to the YZ plane, and is formed to have a substantially V shape when viewed from the vertical direction. The recess 12d is composed of a side surface 12g substantially parallel to the ZX plane and a side surface 12h substantially parallel to the YZ plane, and is formed to have a substantially V shape when viewed from the up-down direction. The recesses 12c and 12d are formed in the entire area of the protrusions 12a and 12b in the vertical direction.

  Further, on the outer peripheral side of the sleeve 12, a magnet fixing portion 12j to which a driving magnet 21 described later constituting the driving mechanism 6 is fixed and a reflecting plate fixed to a reflecting plate 30 described later constituting the position detection mechanism 9 are fixed. A fixing portion 12k is formed. The magnet fixing portion 12 j is formed on the right rear side of the outer peripheral surface of the sleeve 12. The reflector fixing portion 12k is formed on the left front side of the outer peripheral surface of the sleeve 12.

  The fixed body 5 constitutes a substantially square cylindrical cover member 13 constituting the front, rear, left and right side surfaces on the upper end side of the lens driving device 1, a base member 14 constituting the lower end side of the lens driving device 1, and the driving mechanism 6. And a holder 15 for holding the upper end side of a magnetic member 22 to be described later. The cover member 13, the base member 14, and the holder 15 are made of a nonmagnetic material. That is, the fixed body 5 is made of a nonmagnetic material.

  The cover member 13 is formed in a substantially rectangular tube shape with a bottom having a bottom portion 13a and a tube portion 13b. A through hole 13c is formed at the center of the bottom portion 13a disposed on the upper side. The length of the cover member 13 in the vertical direction is longer than the length of the sleeve 12 in the vertical direction. The cover member 13 covers the entire outer peripheral side of the movable body 4 and the drive mechanism 6.

  The base member 14 is formed in a substantially square cylindrical shape with a bottom having a bottom portion 14a and a cylindrical portion 14b. A through hole 14c is formed at the center of the bottom 14a disposed on the lower side. The base member 14 has a coil placement portion 14d for placing drive coils 24 and 25, which will be described later, which constitute the drive mechanism 6, and a sensor fixing portion 14e to which a later-described sensor 29, which constitutes the position detection mechanism 9, is fixed. And are formed. The coil placement portion 14d is formed by cutting out the corner portion at the right rear end of the cylindrical portion 14b, and the sensor fixing portion 14e is formed by cutting out the corner portion at the left front end of the cylindrical portion 14b. .

  A reference surface 14f for determining the reference position of the movable body 4 in the optical axis direction is formed on the upper surface of the bottom portion 14a. The reference surface 14f is formed in a planar shape parallel to the XY plane. The reference surface 14f is formed on the upper surface of the bottom portion 14a at a substantially 90 ° pitch centered on the optical axis L. The lower end surface of the positioning projection 12m formed on the lower end of the sleeve 12 can come into contact with the reference surface 14f. When the lower end surface of the positioning projection 12m is in contact with the reference surface 14f, the movable body 4 Is at the reference position in the optical axis direction.

  Further, a concave portion 14g is formed on the upper surface of the bottom portion 14a, and a lower end side of a magnetic member 22 (described later) constituting the drive mechanism 6 is inserted and fixed. The concave portion 14g is formed at a corner portion at the right rear end of the upper surface of the bottom portion 14a. The concave portion 14g is formed so as to be recessed from the upper surface of the bottom portion 14a.

  Two projecting portions 14h and 14j projecting to the inner peripheral side of the cylindrical portion 14b are formed on the inner peripheral side of the cylindrical portion 14b. The protruding portion 14h is formed on the left rear end side of the inner peripheral surface of the cylindrical portion 14b, and the protruding portion 14j is formed on the right front end side of the cylindrical portion 14b. Further, the protruding portion 14h is formed to protrude to the front side, and the protruding portion 14j is formed to protrude to the left side. The projecting portions 14h and 14j are formed over substantially the entire area of the cylindrical portion 14b in the vertical direction. The left side surface 14k of the protrusion 14h is substantially parallel to the YZ plane. A side surface 14m substantially parallel to the ZX plane is formed on the left side of the side surface 14k. The front side surface 14n of the protrusion 14j is an inclined surface inclined by about 45 ° with respect to the YZ plane and the ZX plane.

  The holder 15 is formed in a substantially square frame shape. A through-hole 15a is formed at the corner on the right rear side of the holder 15 so that an upper end side of a magnetic member 22 described later is inserted and fixed.

  The lower end of the cover member 13 is fixed to the upper surface side of the base member 14. Specifically, the upper surface side of the base member 14 is arranged such that the cylindrical portion 14b is disposed on the inner peripheral side of the cylindrical portion 13b of the cover member 13 and the lower end of the cover member 13 contacts the outer peripheral end portion of the upper surface of the bottom portion 14a. The lower end of the cover member 13 is fixed to the front. The movable body 4 is accommodated in a space surrounded by the cover member 13 and the base member 14.

  The drive mechanism 6 is disposed at the corner of the right rear end of the lens drive device 1. The drive mechanism 6 includes a drive magnet 21 fixed to the movable body 4, a magnetic member 22 fixed to the fixed body 5, a bobbin 23 covering a part of the side surface of the magnetic member 22, and a winding around the bobbin 23. The two drive coils 24 and 25 are provided. The driving coils 24 and 25 are wound around the bobbin 23 so as to overlap in the vertical direction. The driving coils 24 and 25 are disposed on the right rear side of the driving magnet 21 and face the driving magnet 21 from the right rear side. In addition, the drive coil 24 of this embodiment is a first drive coil, and the drive coil 25 is a second drive coil.

  The drive magnet 21 is fixed to the magnet fixing portion 12j of the sleeve 12. The upper end side of the magnetic member 22 is held in the through hole 15 a of the holder 15, and the lower end side of the magnetic member 22 is held in the recess 14 g of the base member 14. The magnetic member 22 is disposed on the right rear side of the drive magnet 21. Therefore, the movable body 4 is urged to the right rear side by the magnetic attractive force generated between the driving magnet 21 and the magnetic member 22. A specific configuration of the drive mechanism 6 will be described later.

  The guide balls 7 and 8 are spherical members formed in a true spherical shape. The guide balls 7 and 8 are disposed between the sleeve 12 and the base member 14. Specifically, the guide ball 7 is disposed between the side surfaces 12 e and 12 f of the sleeve 12 and the side surfaces 14 k and 14 m of the base member 14, and is disposed at the corner of the left rear end of the lens driving device 1. ing. Further, the guide ball 8 is disposed between the side surfaces 12 g and 12 h of the sleeve 12 and the side surface 14 n of the base member 14, and is disposed at a corner portion of the right front end of the lens driving device 1.

  The three guide balls 7 are arranged so as to overlap in the vertical direction, and the three guide balls 8 are arranged so as to overlap in the vertical direction. Further, as described above, the movable body 4 is biased to the right rear side by the magnetic attractive force generated between the driving magnet 21 and the magnetic member 22. That is, the guide ball 7 is sandwiched between the side surfaces 12e and 12f of the sleeve 12 and the side surfaces 14k and 14m of the base member 14, and between the side surfaces 12g and 12h of the sleeve 12 and the side surface 14n of the base member 14. The movable body 4 is urged so that the guide ball 8 is sandwiched therebetween. Therefore, the guide ball 7 is always in contact with the side surfaces 12e and 12f and the side surfaces 14k and 14m, and the guide ball 8 is always in contact with the side surfaces 12g and 12h and the side surface 14n. In this embodiment, the guide ball 8 functions to prevent the movable body 4 from rotating about an axis that is substantially parallel to the optical axis L and passes through the center of the guide ball 7.

  The position detection mechanism 9 is disposed at the corner of the left front end of the lens driving device 1. The position detection mechanism 9 includes an optical sensor 29 including a light emitting element and a light receiving element, and a reflecting plate 30 that reflects light from the light emitting element of the sensor 29 toward the light receiving element. The sensor 29 is fixed to the sensor fixing portion 14 e of the base member 14. An FPC (flexible printed circuit board) 31 is connected to the sensor 29. The reflection plate 30 is fixed to the reflection plate fixing portion 12 k of the sleeve 12. In addition, a support protrusion 14p for supporting the FPC 31 from the outer peripheral side is formed at a corner portion of the left front end of the base member 14.

(Configuration of drive mechanism)
FIG. 5 is a perspective view of the drive magnet 21, the magnetic member 22, and the bobbin 23 shown in FIG. As described above, the drive mechanism 6 includes the drive magnet 21, the magnetic member 22, the bobbin 23, and the drive coils 24 and 25.

  The drive magnet 21 is formed in a substantially rectangular flat plate shape. The driving magnet 21 is fixed to the magnet fixing portion 12j of the sleeve 12 so that the direction inclined by 45 ° with respect to the left-right direction on the XY plane and the thickness direction of the driving magnet 21 substantially coincide with each other. The driving coils 24 and 25 are opposed to each other in a direction inclined by 45 ° with respect to the horizontal direction on the XY plane. Further, the drive magnet 21 is fixed to the magnet fixing portion 12j so that the longitudinal direction thereof substantially coincides with the vertical direction. The driving magnet 21 is configured such that the magnetic pole of the surface 21 a facing the driving coil 24 of the driving magnet 21 is different from the magnetic pole of the facing surface 21 b of the driving magnet 21 facing the driving coil 25. The magnet is magnetized to two poles in the vertical direction. For example, the drive magnet 21 is magnetized so that the magnetic pole of the opposing surface 21a is an S pole and the magnetic pole of the opposing surface 21b is an N pole.

  The magnetic member 22 is made of a soft magnetic material. The magnetic member 22 is formed in a substantially rectangular plate shape. The magnetic member 22 is disposed substantially in parallel with the driving magnet 21. That is, the magnetic member 22 is formed in a flat plate shape whose thickness direction is a direction inclined by 45 ° with respect to the left-right direction on the XY plane. Further, the magnetic member 22 is arranged so that the longitudinal direction thereof substantially coincides with the vertical direction. The length of the magnetic member 22 in the vertical direction is longer than the length of the drive magnet 21 in the vertical direction. As shown in FIG. 2, the upper end side of the magnetic member 22 protrudes above the upper end of the driving magnet 21, and the lower end side of the magnetic member 22 protrudes below the lower end of the driving magnet 21. Yes. The magnetic member 22 of the present embodiment functions as a yoke for forming a magnetic circuit of the drive mechanism 6.

  The bobbin 23 is made of an insulating resin material. The bobbin 23 includes an upper end portion 23a constituting an upper end side portion of the bobbin 23, an intermediate portion 23b constituting an intermediate portion of the bobbin 23 in the vertical direction, a lower end portion 23c constituting a lower end side portion of the bobbin 23, and an upper end A winding part 23d as a third winding part formed between the part 23a and the intermediate part 23b, and a winding part as a fourth winding part formed between the intermediate part 23b and the lower end part 23c 23e.

  The opposing direction of the driving magnet 21 and the driving coils 24 and 25 (that is, the thickness direction of the driving magnet 21 and the magnetic member 22) is the first direction, and the direction orthogonal to the first direction and the vertical direction is the first direction. Assuming two directions, the upper end portion 23a, the intermediate portion 23b, and the lower end portion 23c are formed in a flat, substantially rectangular tube shape having the first direction as a flat direction, and the bobbin 23 has the first direction as a flat direction as a whole. It is formed in the flat substantially square cylinder shape. When viewed in the vertical direction, the inner peripheral surface of the upper end portion 23a, the inner peripheral surface of the intermediate portion 23b, and the inner peripheral surface of the lower end portion 23c coincide with each other, and the outer peripheral surface of the upper end portion 23a and the outer periphery of the intermediate portion 23b The surface and the outer peripheral surface of the lower end 23c coincide.

  The winding portions 23d and 23e are configured by two side surface portions 23f arranged on both sides in the second direction. That is, the winding portions 23d and 23e are not formed with side surfaces in the first direction, and the winding portions 23d and 23e are formed with openings that open in the first direction. When viewed from the top-bottom direction, the inner ends of the side surface portions 23f in the second direction coincide with the inner ends of the upper end portion 23a, the intermediate portion 23b, and the lower end portion 23c in the second direction. On the other hand, when viewed from the up-down direction, the outer end of the side surface portion 23f in the second direction is disposed more inside the second direction than the outer ends of the upper end portion 23a, the intermediate portion 23b, and the lower end portion 23c in the second direction. Has been. In this embodiment, the interval between the two side surface portions 23f arranged on both sides in the second direction is substantially equal to the width W1 of the magnetic member 22. In this embodiment, the thickness of the side surface portion 23f in the first direction is larger than the thickness of the magnetic member 22.

  A magnetic member 22 is inserted and fixed on the inner peripheral side of the bobbin 23. The length of the bobbin 23 in the vertical direction is shorter than the length of the magnetic member 22 in the vertical direction. As shown in FIG. 2, the upper end side of the magnetic member 22 protrudes upward from the upper end of the bobbin 23, and the lower end side of the magnetic member 22 protrudes downward from the lower end of the bobbin 23. The side surface of the magnetic member 22 in the second direction is covered with an upper end portion 23a, an intermediate portion 23b, a lower end portion 23c, and a side surface portion 23f. On the other hand, the side surface of the magnetic member 22 in the first direction is covered only by the upper end portion 23a, the intermediate portion 23b, and the lower end portion 23c, and the winding portion 23d is in a state where the driving coils 24 and 25 are not wound. , 23e, the side surface of the magnetic member 22 in the first direction is exposed. Note that the length of the bobbin 23 in the vertical direction is longer than the length of the driving magnet 21 in the vertical direction.

  A driving coil 24 is wound around the winding portion 23d, and a driving coil 25 is wound around the winding portion 23e. That is, the drive coils 24 and 25 are wound around the magnetic member 22 via the bobbin 23. The driving coils 24 and 25 are wound around the magnetic member 22 via the bobbin 23 so as to overlap in the vertical direction. In this embodiment, the driving coils 24 and 25 are configured by a single conducting wire, and the driving coils 24 and 25 are formed by sequentially winding one conducting wire. Further, the drive coils 24 and 25 are wound around the bobbin 23 so that the winding direction is opposite. For example, when viewed from above and below, the driving coil 24 is wound in the clockwise direction, and the driving coil 25 is wound in the counterclockwise direction.

  On the upper end 23a and the lower end 23c, a pin 23g is formed as a lead end binding pin for binding the end of the lead constituting the driving coils 24, 25. The intermediate portion 23b is formed with a pin 23h as a winding direction changing pin for changing the winding direction of the conductive wire. The pins 23g and 23h are formed on the upper end portion 23a, the intermediate portion 23b, or the lower end portion 23c so as to protrude to the right rear side.

  The conducting wire having one end wound around the pin 23g of the upper end portion 23a is wound around the winding portion 23d and then wound around the pin 23h. After changing the winding direction, the conducting wire is wound around the winding portion 23e. It is wound. Moreover, the other end part of the conducting wire wound by the winding part 23e is wound by the pin 23g of the lower end part 23c. Both ends of the conducting wire wound around the two pins 23g are electrically connected to the FPC 31 by soldering or the like. The upper end portion 23 a and the intermediate portion 23 b serve to prevent the driving coil 24 from being collapsed, and the lower end portion 23 c and the intermediate portion 23 b serve to prevent the driving coil 25 from being collapsed.

  The driving coils 24 and 25 wound around the winding portions 23d and 23e (that is, wound around the two side portions 23f arranged on both sides in the second direction) are formed on the outer peripheral surface of the magnetic member 22. It is formed in a substantially rectangular tube shape so as to be along. Specifically, the drive coils 24 and 25 are formed in a flat and substantially square cylindrical shape with the first direction as the flat direction. In this embodiment, the portion of the magnetic member 22 where the driving coil 24 is wound via the bobbin 23 is the first winding portion, and the driving coil 25 of the magnetic member 22 via the bobbin 23 is wound. The part where is wound is the second winding part.

(Schematic operation of the lens driving device)
6 is a diagram for explaining the state of the driving magnet 21 and the state of the magnetic member 22 when the movable body 4 shown in FIG. 2 moves in the optical axis direction and before and after that.

  In the lens driving device 1 configured as described above, when a current is supplied to the driving coils 24 and 25, for example, the driving magnet 21 at the position shown in FIG. As shown in FIG. 6 (B), it moves upward. That is, the movable body 4 moves upward. In this embodiment, as shown in FIG. 6B, the drive coils 24 and 25 are wound so that the magnetic member 22 is magnetized. At this time, the gap between the drive magnet 21 and the magnetic member 22 is wound. The driving force of the movable body 4 that moves upward is increased by the action of the magnetic attractive force and the magnetic repulsive force that occur in the above.

  When the supply of current to the driving coils 24 and 25 is stopped in the state shown in FIG. 6B, the magnetized magnetic member 22 returns to the original state, and the driving magnet 21 and the magnetic member are returned. As shown in FIG. 6C, the position of the driving magnet 21 is held by the magnetic attractive force acting between the two magnets 22 and 22. That is, the position of the movable body 4 is maintained. In this state, when reverse current is supplied to the drive coils 24 and 25, the drive magnet 21 starts to move downward as shown in FIG. 6D due to the Lorentz force. . That is, the movable body 4 starts to move downward. At this time, since the magnetic member 22 is magnetized as shown in FIG. 6D, the magnetic attraction force and the magnetic repulsive force generated between the driving magnet 21 and the magnetic member 22 cause the lower side. The driving force of the movable body 4 that moves to increases.

  Further, as described above, the movable body 4 is urged to the right rear side by the magnetic attractive force generated between the driving magnet 21 and the magnetic member 22, and the guide ball 7 has the side surfaces 12e and 12f. The guide ball 8 is in contact with the side surfaces 12g and 12h and the side surface 14n. Therefore, when a current is supplied to the driving coils 24 and 25, the movable body 4 moves along the guide balls 7 and 8 in the optical axis direction while being urged to the right rear side. At this time, the guide balls 7 and 8 rotate as the movable body 4 moves.

  After the movable body 4 has moved to the predetermined position, the movable body 4 is held at the predetermined position by the magnetic attractive force acting between the driving magnet 21 and the magnetic member 22. Depending on the posture or the like, the movable body 4 may be displaced from a predetermined position. In this case, a current is supplied to the drive coils 24 and 25 based on the detection result of the position of the movable body 4 by the position detection mechanism 9. That is, in this embodiment, the current supplied to the driving coils 24 and 25 is feedback-controlled based on the detection result of the position detection mechanism 9 so that the movable body 4 remains at a predetermined position.

(Main effects of this form)
As described above, in this embodiment, the drive coils 24 and 25 are wound around the bobbin 23 on which the pin 23h is formed. For this reason, in this embodiment, even if the winding direction of the driving coil 24 and the winding direction of the driving coil 25 are opposite to each other, the conductors constituting the driving coils 24 and 25 using the pin 23h. The winding direction of can be easily changed. Further, in this embodiment, since the pin 23g is formed on the bobbin 23, it is possible to easily process the end portions of the conducting wires constituting the driving coils 24 and 25. Therefore, in this embodiment, the winding operation of the drive coils 24 and 25 can be easily performed.

  In this embodiment, the magnetic member 22 is formed in a flat plate shape having the first direction as the thickness direction, and the driving coils 24 and 25 are flat in the first direction so as to be along the outer peripheral surface of the magnetic member 22. It is formed in the shape of a flat, substantially square cylinder that is oriented. Therefore, in this embodiment, in order to secure the driving force of the driving mechanism 6, even if the driving coils 24 and 25 are wound around the magnetic member 22 through the bobbin 23 a predetermined number of times, the driving coils 24 and 25 are not connected. It becomes possible to shorten the length of the conducting wire. Therefore, in this embodiment, power consumption in the drive coils 24 and 25 can be reduced.

  In particular, in this embodiment, the winding portions 23d and 23e of the bobbin 23 are configured by two side surface portions 23f disposed on both sides in the second direction, and the winding portions 23d and 23e are provided with side surfaces in the first direction. Is not formed, it is possible to further shorten the length of the conductive wire constituting the drive coils 24 and 25, and to further reduce the power consumption in the drive coils 24 and 25. Further, in this embodiment, the side surfaces in the first direction are not formed on the winding portions 23d and 23e, so that even if the driving coils 24 and 25 are wound around the magnetic member 22 via the bobbin 23, It is possible to reduce the distance between the driving magnet 21 and the magnetic member 22 in one direction. Therefore, in this embodiment, the density of the magnetic flux passing through the drive coils 24 and 25 can be increased, and as a result, the drive force of the drive mechanism 6 can be increased. Further, in this embodiment, since the side surfaces in the first direction are not formed on the winding portions 23d and 23e, compared with the case where the side surfaces in the first direction are formed on the winding portions 23d and 23e, The magnetic attractive force between the magnetic member 22 and the drive magnet 21 can be increased.

  In this embodiment, the length of the magnetic member 22 in the vertical direction is longer than the length of the driving magnet 21 in the vertical direction. Further, the upper end side of the magnetic member 22 protrudes upward from the upper end of the driving magnet 21, and the lower end side of the magnetic member 22 protrudes downward from the lower end of the driving magnet 21. The length of the magnetic member 22 in the vertical direction is shorter than the length of the driving magnet 21 in the vertical direction, and the upper and lower ends of the magnetic member 22 are arranged on the inner side in the vertical direction than the upper and lower ends of the driving magnet. In this case, when no current is supplied to the drive coils 24 and 25, the magnetic attractive force toward the center of the magnetic member 22 in the vertical direction is likely to act on the drive magnet 21, so that the movable body is moved to a predetermined position. The driving force of the driving mechanism 6 necessary for moving the motor 4 must be increased. On the other hand, in this embodiment, since the magnetic attraction force toward the center of the magnetic member 22 in the vertical direction is less likely to act on the driving magnet 21, the driving mechanism 6 necessary for moving the movable body 4 to a predetermined position. The driving force can be reduced.

  In this embodiment, the guide ball 7 is in contact with the side surfaces 12e and 12f and the side surfaces 14k and 14m, and is urged to the right rear side so that the guide ball 8 is in contact with the side surfaces 12g and 12h and the side surface 14n. The movable body 4 moves along the guide balls 7 and 8 in the optical axis direction. Therefore, in this embodiment, it is possible to suppress the shakiness of the movable body 4 when moving in the optical axis direction. Further, in this embodiment, since the sliding resistance when the movable body 4 moves in the optical axis direction can be reduced, the driving force of the drive mechanism 6 necessary for moving the movable body 4 to a predetermined position. Can be reduced.

  In this embodiment, the driving mechanism 6 is disposed at the corner of the right rear end of the lens driving device 1 that is substantially square when viewed from the vertical direction, and position detection is performed at the corner of the left front end of the lens driving device 1. A mechanism 9 is arranged. In this embodiment, the guide ball 7 is disposed at the corner of the left rear end of the lens driving device 1, and the guide ball 8 is disposed at the corner of the right front end of the lens driving device 1. That is, in this embodiment, the drive mechanism 6, the position detection mechanism 9, and the guide balls 7 and 8 are disposed at the four corners of the lens drive device 1 that are likely to become a dead space. Therefore, in this embodiment, the lens driving device 1 can be downsized in the radial direction of the lens 2. Alternatively, the diameter of the lens 2 can be increased without increasing the size of the lens driving device 1 in the radial direction of the lens 2.

  In this embodiment, the drive magnet 21 is fixed to the movable body 4, and the drive coils 24 and 25 are fixed to the fixed body 5. Therefore, as compared with the case where the driving coils 24 and 25 are attached to the movable body 4, the processing of the driving coils 24 and 25 is facilitated. Further, in this embodiment, since the fixed body 5 is formed of a nonmagnetic material, the drive mechanism 6 is driven by the magnetic attractive force generated between the drive magnet 21 fixed to the movable body 4 and the fixed body 5. It is possible to prevent the power from being reduced.

(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 drive mechanism 6 is disposed at the corner of the right rear end of the lens drive device 1. In addition to this, for example, the driving mechanism 6 may be disposed at each of the four corners of the lens driving device 1, or two corners disposed on the diagonal line of the four corners of the lens driving device 1. The drive mechanism 6 may be disposed in each of the parts.

  In the embodiment described above, the magnetic member 22 is formed in a substantially rectangular flat plate shape. In addition, for example, a portion of the magnetic member 22 where the driving coil 24 is wound via the bobbin 23 and a portion of the magnetic member 22 where the driving coil 25 is wound via the bobbin 23 are provided. The magnetic member 22 may be formed in any shape as long as it is formed in a flat plate shape having the first direction as its thickness direction.

  In the embodiment described above, the winding portions 23d and 23e of the bobbin 23 are configured by the two side surface portions 23f disposed on both sides in the second direction, and the winding portions 23d and 23e have side surfaces in the first direction. Is not formed, but side surfaces in the first direction may be formed in the winding portions 23d and 23e.

  In the embodiment described above, the length of the magnetic member 22 in the vertical direction is longer than the length of the drive magnet 21 in the vertical direction, and the upper end side of the magnetic member 22 is higher than the upper end of the drive magnet 21. The lower end side of the magnetic member 22 protrudes downward from the lower end of the drive magnet 21. In addition, for example, the length of the magnetic member 22 in the vertical direction is shorter than the length of the driving magnet 21 in the vertical direction, and the upper and lower ends of the magnetic member 22 are higher in the vertical direction than the upper and lower ends of the driving magnet 21. It may be arranged inside. In this case, when no current is supplied to the drive coils 24 and 25, the magnetic attractive force toward the center of the magnetic member 22 in the vertical direction is likely to act on the drive magnet 21. Therefore, the movable body 4 can be stopped at a fixed position when no current is supplied to the driving coils 24 and 25.

  In the embodiment described above, the movable body 4 is light-transmitted by the guide ball 7 disposed at the corner of the left rear end of the lens driving device 1 and the guide ball 8 disposed at the corner of the right front end of the lens driving device 1. It is guided in the axial direction. In addition to this, for example, the movable body 4 may be guided in the optical axis direction by a guide ball disposed at the corner of the left front end of the lens driving device 1. In this case, the position detection mechanism 9 is disposed, for example, at the corner at the left rear end or the corner at the right front end of the lens driving device 1.

  In the embodiment described above, the movable body 4 is guided in the optical axis direction by the guide balls 7 and 8. In addition to this, for example, a guide shaft whose axial direction is the vertical direction is formed in the fixed body 5, and an insertion hole through which the guide shaft is inserted is formed in the movable body 4. By the guide shaft and the insertion hole, The movable body 4 may be guided in the optical axis direction. In this case, the guide shaft and the insertion hole are disposed, for example, at the corner portion of the left front end of the lens driving device 1.

  The lens driving device 1 may include a leaf spring that connects the movable body 4 and the fixed body 5 in place of the guide balls 7 and 8. In this case, it is preferable that the driving mechanism 6 is disposed at each of the four corners of the lens driving device 1 or at two positions on the diagonal line of the four corners of the lens driving device 1. In this way, even when the movable body 4 and the fixed body 5 are connected by the leaf spring, it becomes possible to maintain the balance of the movable body 4 when the movable body 4 moves in the optical axis direction. When the movable body 4 moves in the optical axis direction, it is possible to prevent problems such as the tilt of the movable body 4.

  In the embodiment described above, the driving magnet 21 is fixed to the sleeve 12, and the magnetic member 22, the bobbin 23 and the driving coils 24 and 25 are fixed to the base member 14. In addition, for example, the magnetic member 22, the bobbin 23 and the driving coils 24 and 25 may be fixed to the sleeve 12, and the driving magnet 21 may be fixed to the base member 14.

  In the embodiment described above, the position detection mechanism 9 is an optical position detection mechanism including the optical sensor 29 and the reflection plate 30. In addition, for example, the position detection mechanism 9 may be an electromagnetic detection mechanism including a magnetic sensor and a detection magnet. Moreover, in the form mentioned above, although the lens drive device 1 is formed so that the shape when seen from the optical axis direction is a substantially square shape, the lens drive device 1 is when seen from the optical axis direction. You may form so that a shape 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, a circular shape, or an elliptical shape.

DESCRIPTION OF SYMBOLS 1 Lens drive device 2 Lens 4 Movable body 5 Fixed body 6 Drive mechanism 7, 8 Guide ball 9 Position detection mechanism 21 Drive magnet 21a Opposite surface (opposite surface with 1st drive coil)
21b Opposing surface (facing surface with second driving coil)
22 Magnetic member 23 Bobbin 23d Winding part (third winding part)
23e Winding part (4th winding part)
23f Side part 23g Pin (Pin for connecting end of conductor)
23h Pin (Pin for changing winding direction)
24 Driving coil (first driving coil)
25 Driving coil (second driving coil)
L Optical axis Z Optical axis direction

Claims (5)

A movable body that holds the lens and is movable in the optical axis direction of the lens, a fixed body that accommodates the movable body, a drive mechanism for driving the movable body in the optical axis direction, and the movable body, A guide ball disposed between the fixed body and guiding the movable body in the optical axis direction; a position detection mechanism for detecting a position of the movable body in the optical axis direction; and the optical axis. A lens driving device formed so that the shape when viewed from the direction is a substantially square shape,
The drive mechanism includes a drive magnet fixed to one of the movable body or the fixed body, a magnetic member fixed to the other of the movable body or the fixed body, and an insulating material. a bobbin covering at least a portion of the side surface, Ru and a first drive coil and the second drive coil are arranged to overlap in the optical axis direction while facing the drive magnet wound on the bobbin And, when viewed from the optical axis direction, disposed at one of the four corners of the lens driving device,
The driving magnet has a different magnetic pole from a magnetic pole on the surface facing the first driving coil of the driving magnet and a magnetic pole on the surface facing the second driving coil of the driving magnet. So that it is magnetized
The winding direction of the second driving coil is opposite to the winding direction of the first driving coil,
A first winding portion of the magnetic member, which is a portion around which the first driving coil is wound via the bobbin, and a winding of the second driving coil via the bobbin of the magnetic member. The second winding part, which is a portion to be formed, is formed in a flat plate shape having a thickness direction in a facing direction between the first driving coil and the second driving coil and the driving magnet,
The first driving coil is formed in a substantially cylindrical shape along the outer peripheral surface of the first winding portion, and the second driving coil is substantially extended along the outer peripheral surface of the second winding portion. Formed in a cylindrical shape ,
The guide balls are arranged at two locations arranged on the diagonal line of the remaining three corners of the lens driving device except for one location where the drive mechanism is arranged when viewed from the optical axis direction. And
The position detection mechanism is disposed at the remaining one of the four corners of the lens driving device excluding three positions where the drive mechanism and the guide ball are disposed when viewed from the optical axis direction,
The movable body is attached in a direction in which the movable body and the guide ball come into contact with each other and the fixed body and the guide ball come into contact with each other by a magnetic attractive force generated between the driving magnet and the magnetic member. A lens driving device characterized by being biased .   The third winding part of the bobbin is a part around which the first driving coil is wound, and the fourth winding part of the bobbin is a part around which the second driving coil is wound. The first driving coil and the second driving coil and the driving magnet are configured by two side portions disposed on both sides in a direction orthogonal to the facing direction of the driving magnet and the optical axis direction. The lens driving device according to claim 1. Conductive wire end binding pins are formed on both ends of the bobbin in the optical axis direction for connecting the ends of the conductive wires constituting the first drive coil and the second drive coil. ,
A third winding part of the bobbin that is a part around which the first driving coil is wound, and a fourth winding part that is a part around which the second driving coil is wound around the bobbin. The lens driving device according to claim 1, wherein a winding direction changing pin for changing a winding direction of the conducting wire is formed therebetween. The length of the magnetic member in the optical axis direction is longer than the length of the driving magnet in the optical axis direction,
The both end sides of the magnetic member in the optical axis direction protrude outward in the optical axis direction from both ends of the driving magnet in the optical axis direction. The lens driving device described. The drive magnet is fixed to the movable body,
The magnetic member is fixed to the fixed body,
The fixed body, the lens driving device according to any one of what is formed of a non-magnetic material from claim 1, wherein 4.

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