JP2008112200A - Lens drive device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens drive device capable of preventing occurrence of failure such as plastic deformation or rupture of a spring member when receiving a strong impact such as a drop impact even if the arm part of the spring member must be arranged in a narrow area. <P>SOLUTION: In the lens drive device 1, the spring members 14x and 14y for supporting a moving lens body movably in an optical axis direction are equipped with four pieceses of arm parts 143a to 143b between outside coupling parts 141a to 141d and an inside coupling part 142, and the arm part 143a is equipped with a meandering part 145a where a plurality of elongation parts 146a extended in a periphery direction are connected in series by a turn-back part 147a. The other arm parts 143b, 143c and 143d are constituted in the same way. The four arm parts 143a to 143d are arranged in four corners of a nearly rectangular back yoke 16. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens driving device that forms an image of a subject by driving a lens in the direction of an optical axis.

  In recent years, as camera-equipped mobile phones equipped with cameras have become popular, opportunities for photographing various subjects using the mobile phones have increased. For example, you can shoot a subject that is far away from the camera lens, such as a friend or landscape (normal shooting), or a subject that is close to the camera lens, such as a bus timetable or petals (close-up shooting) There is a case.

  In close-up photography (macro photography), the lens position of the camera needs to be slightly closer to the subject side than the lens position during normal photography. For this reason, this type of photographic lens system includes a drive mechanism that drives the lens to move in the direction of the optical axis, so that the lens can be moved in the direction of the optical axis by driving the drive mechanism by switching a switch. (For example, refer to Patent Document 1).

  The lens driving device disclosed in Patent Document 1 includes a lens barrel including a lens, a moving lens body that holds the lens barrel, and a support that supports the moving lens body so as to be movable in the optical axis direction of the lens. The moving lens body is provided with a drive magnet, and the support body is provided with a drive coil and two magnetic pieces (yokes). When energization of the drive coil is stopped, the moving body is held at a position closer to one of the two magnetic pieces using the magnetic adsorption between the drive magnet and the magnetic piece. Yes.

  Here, according to Patent Document 1, the range in which the moving lens body moves in the optical axis direction of the lens is limited to a predetermined range. More specifically, as shown in Patent Document 1, the moving lens body (lens barrel) abuts on a protruding edge formed inwardly at the rear end of the first case divided body. Accordingly, the lens barrel does not move to the rear end side any more. In general, a guide mechanism including a concave portion (or convex portion) that engages with a convex portion (or concave portion) of the lens barrel is often formed in the vicinity of the protruding edge. This is to form a detent structure that prevents the lens barrel from rotating due to the impact or vibration of the lens moving body.

  Further, in the lens driving device described above, a configuration in which the moving lens body and the support body are connected by a spring member is often employed, and the spring member is connected to the outer connecting portion connected to the support body and the moving lens body. A ring frame-shaped inner connecting portion and an arm portion connecting the outer connecting portion and the inner connecting portion, and the arm portion meandering on the outer peripheral side of the moving lens body are proposed. (See Patent Documents 2 and 3).

In such a spring member, the arm portion exhibits a spring property between the outer connecting portion and the inner connecting portion, whereby the spring member can move the moving lens body when the moving lens body moves in the optical axis direction. Controls the amount of movement in the optical axis direction. In addition, the portable device has many opportunities to receive vibrations and impacts due to the nature of being carried, but such vibrations and impacts are absorbed by the arm portion.
Japanese Patent Laying-Open No. 2005-37865 (FIG. 2) JP 2006-201525 A JP 2006-227103 A

  The inventor of the present application proposes a spring member having a shape that can cope with the case where the outer shape of the lens driving device is a rectangular parallelepiped. In this case, the spring member has a cross-section substantially perpendicular to the optical axis. The frame is arranged in a narrow region sandwiched between the frame portion of the rectangular cylindrical support and the cylindrical moving lens body on the outer periphery. However, when the spring member described in Patent Documents 2 and 3 is used for the lens driving device having such a structure, there is a gap between the outer coupling portion connected to the support and the inner coupling portion connected to the moving lens body. Since it is narrow, the shape of the arm portion and the like is low in design freedom, and sufficient springiness cannot be secured. In addition, when the lens drive device receives a strong impact such as a drop impact, the moving lens body moves violently in the direction perpendicular to the optical axis direction (left and right direction and circumferential direction) and in the oblique direction (tilt direction) with respect to the optical axis direction. In this case, the conventional spring member is likely to be plastically deformed or broken, and the lens drive device is liable to have a problem such as a stroke failure.

  In view of the above problems, the subject of the present invention is that the subject of the present invention is a spring when subjected to a strong impact such as a drop impact even when the arm portion of the spring member has to be arranged in a narrow region. An object of the present invention is to provide a lens driving device capable of preventing the occurrence of problems such as plastic deformation and fracture of members.

  In order to solve the problems as described above, in the present invention, a moving lens body that holds a lens, and a support body that supports the moving lens body so as to be movable in the optical axis direction of the lens via a spring member, In the lens driving device having a driving mechanism for driving the moving lens body in the optical axis direction, the support body includes a polygonal cylindrical frame portion surrounding the moving lens body, and the spring member includes the support member. An outer connecting part connected to a body, an inner connecting part connected to the moving lens body, and an arm part connected to the inner connecting part and the outer connecting part, wherein the arm part has a plurality of extensions. At least two corners formed by an outer peripheral surface of the movable lens body and a side wall surface adjacent to the frame portion. Characterized in that it is location.

  In the present invention, as a spring member that supports the movable lens body so as to be movable in the optical axis direction, an arm portion is provided between the outer connecting portion and the inner connecting portion, and the arm portion is adjacent to the polygonal cylindrical frame portion. It arrange | positions in at least 2 places among the some corner | angular parts formed by the side wall surface and the outer peripheral surface of the moving lens body. Therefore, even when the space surrounded by the inner periphery of the frame portion and the outer periphery of the moving lens body is narrow, the arm portions are disposed at relatively wide corner portions, so that the number of extending portions and folded portions can be increased. Therefore, excessive displacement in the optical axis direction of the moving lens body due to impact or the like, displacement in the left-right direction orthogonal to the optical axis of the moving lens body, rotational displacement in the circumferential direction of the moving lens body, moving lens Even when a displacement in the oblique direction (tilt direction) occurs with respect to the optical axis of the body, the spring member exhibits excellent vibration resistance and impact resistance. Further, the spring member is excessively displaced in the optical axis direction of the moving lens body due to an impact or the like, is displaced in the left-right direction orthogonal to the optical axis of the moving lens body, and is rotationally displaced in the circumferential direction of the moving lens body Even when a displacement in the oblique direction (tilt direction) occurs with respect to the optical axis of the moving lens body, the arm portion is plastically deformed because it has sufficient rigidity to withstand the stress caused by the displacement. The situation can be avoided reliably.

  In the present invention, it is preferable that the plurality of extending portions extend in the circumferential direction in the meandering portion. If comprised in this way, the number of the expansion | extension part and a folding | returning part can be increased. Therefore, excessive displacement in the optical axis direction of the moving lens body due to impact or the like, displacement in the left-right direction orthogonal to the optical axis of the moving lens body, rotational displacement in the circumferential direction of the moving lens body, moving lens Even when a displacement in the oblique direction (tilt direction) occurs with respect to the optical axis of the body, the spring member exhibits excellent vibration resistance and impact resistance. In addition, since it has sufficient rigidity to withstand the stress caused by such displacement, it is possible to reliably avoid the situation where the arm portion is plastically deformed.

  In the present invention, in the meandering portion, it is preferable that three or more elongated portions are arranged in parallel in the radial direction. As described above, when the number of the extending parts and the folded parts is increased, the moving lens body can withstand the stress applied when the moving lens body is moved in the direction orthogonal to the optical axis direction or inclined in the oblique direction with respect to the optical axis. Can do.

  In the present invention, it is preferable that the plurality of extending portions include extending portions extending substantially parallel to each other. If comprised in this way, even when an arm part deform | transforms, it can prevent that extended parts contact and are damaged.

  In the present invention, it is preferable that the plurality of extending portions have a portion located radially inward longer than a portion located radially outward. If comprised in this way, the number of the expansion | extension part and a folding | returning part can be increased. Therefore, since the spring member exhibits excellent vibration resistance and impact resistance and has sufficient rigidity, it is possible to reliably avoid the situation where the arm portion is plastically deformed.

  In this invention, it is preferable that the said arm part is provided with the substantially triangular outer periphery outline shape provided with the base on the radial inside, and was provided with the vertex in the back of the said corner | angular part. If comprised in this way, the number of the expansion | extension part and a folding | returning part can be increased. Therefore, since the spring member exhibits excellent vibration resistance and impact resistance and has sufficient rigidity, it is possible to reliably avoid the situation where the arm portion is plastically deformed.

  In the present invention, it is preferable that the meandering portion is formed in a region shifted in a circumferential direction from a portion located on the radially outer side of a connection portion between the inner coupling portion and the arm portion. If comprised in this way, since the formation range of an arm part can be ensured widely, a sufficiently long extended part can be formed.

  In this invention, it is preferable that the width dimension of the connection part of the said inner side connection part and the said arm part is wider than the width dimension of the said meandering part. If comprised in this way, even if a big load is added to an inner side connection part, it will not be damaged. In addition, when the inner connecting portion is formed wide, stress when the moving lens body moves in a direction perpendicular to the optical axis direction or tilted with respect to the optical axis is applied to the arm portion. It is possible to efficiently absorb stress when the moving lens body moves in a direction orthogonal to the optical axis direction or tilts in an oblique direction with respect to the optical axis.

  In the present invention, when viewed from the optical axis direction, the outer peripheral shape of the moving lens body is circular, and the outer peripheral surface of the moving lens body is at least one virtual polygon connecting the centers of adjacent sides in the frame portion. It is possible to adopt a configuration that projects to the outer peripheral side from the side. According to the present invention, since the arm portion of the spring member is disposed in a space surrounded by the outer periphery of the moving lens body and the inner periphery of the frame portion, the arm portion can be disposed depending on the size of the moving lens body and the frame portion. The size of the space changes. In particular, in the configuration in which the outer periphery of the moving lens body is arranged on the outer peripheral side with respect to at least one side of the virtual polygon connecting the centers of the sides of the frame portion, the space described above becomes narrower. However, in the present invention, the arm portion of the spring member is disposed at the corner portion formed by the adjacent side wall surfaces on the side wall surface constituting the frame portion, so that the outer periphery of the moving lens body and the inner periphery of the frame portion are arranged. Even when the enclosed space is small, it can be dealt with.

  In the present invention, when viewed from the optical axis direction, a configuration in which the outer peripheral surface of the moving lens body projects to the outer peripheral side from any side of the virtual polygon may be employed.

  In this invention, it is preferable that the magnet which comprises the said drive mechanism is each arrange | positioned at at least 2 places among these corner | angular parts. According to the present invention, if the magnet is arranged in the corner formed by the adjacent side wall surfaces, the magnet can be sufficiently used even when the space surrounded by the outer periphery of the moving lens body and the inner periphery of the frame portion is narrow. A magnet having a volume can be disposed, and sufficient thrust can be applied to the moving lens body.

  In this invention, it is preferable that the said arm part and the said magnet are overlapped and arrange | positioned in the said optical axis direction at at least 2 places among these corner | angular parts. If comprised in this way, since the area which an arm part and a magnet occupy can be narrowed, size reduction of the whole lens drive device can be achieved.

  In the lens driving device according to the present invention, even when the space surrounded by the inner periphery of the frame portion and the outer periphery of the moving lens body is narrow, since the arm portion of the spring member is disposed at a relatively wide corner, the extension portion and the folding portion are arranged. The number of parts can be increased. Therefore, due to an impact or the like, the moving lens body is excessively displaced in the optical axis direction, the displacement of the moving lens body in the left-right direction orthogonal to the optical axis, the rotational displacement of the moving lens body in the circumferential direction, the moving lens body Even when displacement in the oblique direction (tilt direction) occurs with respect to the optical axis, the spring member exhibits excellent vibration resistance and impact resistance. Further, the spring member is excessively displaced in the optical axis direction of the moving lens body due to an impact or the like, is displaced in the left-right direction orthogonal to the optical axis of the moving lens body, and is rotationally displaced in the circumferential direction of the moving lens body Even when a displacement in the oblique direction (tilt direction) occurs with respect to the optical axis of the moving lens body, the arm portion is plastically deformed because it has sufficient rigidity to withstand the stress caused by the displacement. The situation can be avoided reliably.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The lens driving device described below can be attached to various electronic devices in addition to the camera-equipped mobile phone. For example, it can be used for a thin digital camera, PHS, PDA, bar code reader, surveillance camera, camera for checking the back of a car, a door having an optical authentication function, and the like.

[Embodiment 1]
(overall structure)
FIGS. 1A and 1B are an external view and an exploded perspective view, respectively, of the front of the lens driving device according to Embodiment 1 of the present invention viewed obliquely from above.

  1A and 1B, a lens driving device 1 according to the present embodiment is a thin camera used for a camera-equipped mobile phone or the like. For example, three lenses 121 are placed along a subject (object side) along the optical axis direction. For moving in both directions, A direction (front side) approaching and B direction (rear side) approaching the opposite side (image side) to the subject, and has a substantially rectangular parallelepiped shape. The lens driving device 1 generally includes a moving lens body 3 holding a cylindrical lens barrel 12 provided with three lenses 121 and a fixed aperture on the inside, and moves the moving lens body 3 along the optical axis direction. It has a lens driving mechanism 5 and a support 2 on which the lens driving mechanism 5 and the moving lens body 3 are mounted. The moving lens body 3 includes a cylindrical sleeve 13, and a cylindrical lens barrel 12 is fixed to the inside thereof. Therefore, the outer shape of the moving lens body 3 is defined by the sleeve 13 and has a substantially cylindrical shape.

  In this embodiment, the support 2 is a rectangular holder 19 for holding an image sensor (not shown) on the image side, a rectangular case 11 positioned on the subject side, and a plate shape that covers the subject side of the case 11. A circular incident window 110, 180 is provided in the center of the case 11 and the plate-like cover 18 for taking the reflected light from the subject into the lens. The support 2 further includes a square cylindrical back yoke 16 (frame portion) sandwiched between the holder 19 and the case 11, and the back yoke 16 is chained to the coil 30 together with a magnet 17 described later. The interlinkage magnetic field generator 4 that generates the alternating magnetic field is configured. If the sleeve 13 is formed of a magnetic material, the sleeve 13 can also be used as a part of the interlinkage magnetic field generator 4.

  The lens driving mechanism 5 includes a coil 30 wound around the outer peripheral surface of the sleeve 13 and a linkage magnetic field generator 4 that generates a linkage magnetic field in the coil 30. The lens 30 and the linkage magnetic field generator 4 generate magnetism. A drive mechanism 5a is configured. The interlinkage magnetic field generator 4 includes four magnets 17 that face the coil 30 on the outer peripheral side, and a square cylindrical back yoke 16 made of a ferromagnetic plate such as a steel plate.

  The back yoke 16 is sandwiched between the holder 19 and the case 11, and the back yoke 16 is exposed on the side surface of the lens driving device 1 and constitutes a side surface portion thereof. Further, the back yoke 16 is in a state of surrounding the moving lens body 3.

  The lens driving mechanism 5 further includes spring members 14 x and 14 y between the back yoke 16 and the holder 19 and between the back yoke 16 and the case 11. The two spring members 14x and 14y are both made of metal and are formed by pressing or etching a plate material having a predetermined thickness. The thickness (plate thickness) of the two spring members 14x and 14y in the optical axis direction may be changed for convenience. Moreover, although the material which comprises the two spring members 14x and 14y differs from each other, the structure which makes thickness the same may be employ | adopted. Here, the spring member 14x disposed between the back yoke 16 and the holder 19 is divided into two spring pieces 14a and 14b, and the two ends of the coil 30 are connected to the spring pieces 14a and 14b, respectively. Is done. At that time, of the two terminals of the coil 30, the object-side terminal passes under a groove (not shown) formed on the outer peripheral surface of the sleeve 13, and then dives under the coil 30 to the spring piece 14 a. Has been routed. Further, in the spring member 14 x held between the back yoke 16 and the holder 19, terminals 140 a and 140 b are respectively formed on the spring pieces 14 a and 14 b, and the spring member 14 x can be used as a power supply member for the coil 30. Function.

  In this embodiment, the spring member 14x is divided into two spring pieces 14a and 14b. However, such division is performed after being mounted on the lens driving device 1, and the shape before cutting and cutting. The subsequent function is the same as that of the spring member 14 y disposed between the back yoke 16 and the case 11.

  The back yoke 16 is larger than the dimension in the optical axis direction of the region where the coil 30 is disposed and the dimension in the optical axis direction of the drive magnet. For this reason, the leakage magnetic flux from the magnetic path comprised between the magnet 17 and the coil 30 can be reduced, and the linearity between the movement amount of the sleeve 13 and the current flowing through the coil 30 can be improved. it can. Therefore, in the back yoke 16 of this embodiment, for example, the effect of reducing the above-described leakage magnetic flux can be obtained without forming the shape of the back yoke 16 so as to cover the side surface, the lower surface, or the upper surface of the coil 30. .

  The back yoke 16 has a substantially rectangular outer peripheral shape, a pair of opposing side surface parts 161 are formed in a flat shape, and the other pair of opposing side surface parts 162 have both end portions 163 recessed inward, A convex portion 16a that protrudes in a step shape is formed on the outside at the center.

  The lens driving mechanism 5 may have a ring-shaped, rod-shaped, or spherical magnetic piece (not shown) held at the upper end of the sleeve 13, and such a magnetic piece acts between the magnet 17. An urging force in the optical axis direction is applied to the moving lens body 3 by the suction force. For this reason, since it is possible to prevent the moving lens body 3 from being displaced by its own weight when no power is supplied, the moving lens body 3 can be maintained in a desired posture. Further, when the magnetic piece is formed in a ring shape, it acts as a kind of back yoke, and the leakage magnetic flux from the magnetic path formed between the magnet 17 and the coil 30 can be reduced.

  The case 11 covers the subject side of the back yoke 16 and has a plate portion 115 in which an incident window 110 is formed at the center. At the four corners of the plate portion 115, a step portion 111 protruding to the subject side and a small protrusion 112 extending to the image sensor side are formed, and a notch of the plate-like cover 18 is formed on a pair of opposing sides of the plate portion 115. A holding portion 113 that fits in 187 is formed. The holder 19 has small protrusions 192 at the four corners extending toward the subject side, and columnar members 191 extend from the side surface toward the subject side. The small protrusion 192 of the holder 19 and the small protrusion 112 of the case 11 are used when connecting the two spring members 14x and 14y to the support body 2, respectively.

  The plate cover 18 is formed of a nonmagnetic thin plate (for example, SUS304), and has a top plate portion 185 that covers the subject side of the case 11. An incident window 180 is formed in the center of the top plate portion 185. Although the top plate portion 185 has a substantially rectangular shape, rectangular cutouts 186 and 187 are formed in the vicinity of the four corners and the center of one side facing each other. A pair of engaging leg portions 181 extends downward from a pair of opposing side portions of the top plate portion 185. Further, in the other pair of opposite side portions of the top plate portion 185, a pair of engaging leg portions 182 extend downward from the vicinity of both ends sandwiching the notch 187, respectively. Each of the engaging legs 181 and 182 is formed with a through hole 183 in the vicinity of the central region thereof.

  Accordingly, when the plate cover 18 is overlaid with the holder 19, the spring member 14 x, the back yoke 16, the spring member 14 y, and the case 11 being overlaid, the notch 187 of the plate cover 18 is formed on the holding portion 113 of the case 11. The plate-like cover 18 is positioned on the upper surface of the case 11 by fitting each. At this time, step portions 111 formed at the four corners of the case 11 are arranged in the notches 186 formed at the four corners of the top plate portion 185. Further, the engaging leg portion 181 is in contact with the side surface portion 161 of the back yoke 16, the engaging leg portion 182 is in contact with the side surface portion 162 of the back yoke 16, and is disposed so as to sandwich the convex portion 16a. In the engaging legs 181 and 182 arranged in this manner, for example, the side surfaces 161 and 162 and the engaging legs 181 and 182 are fixed by applying anaerobic adhesive from the through holes 183 included in each, The plate-shaped cover 18 can be fixed to the back yoke 16 by joining the side surface portions 161 and 162 and the engaging leg portions 181 and 182 by laser welding.

  In this embodiment, each of the four magnets 17 is fixed to four corners of the inner peripheral surface of the back yoke 16. Each of the four magnets 17 is divided into two in the optical axis direction, and in any case, the inner surface and the outer surface are magnetized to different poles. In the four magnets 17, for example, the inner surface is magnetized to the N pole in the upper half, the outer surface is magnetized to the S pole, and the inner surface is magnetized to the S pole in the lower half, and the outer surface is magnetized to the N pole. It is magnetized. Therefore, the coil 30 is divided into two corresponding to the upper half and the lower half of the magnet 17, and the winding directions of the two divided coils are opposite. As described above, if the magnet 17 is divided into four corners, the thin portion of the magnet 17 has a thin portion even when the gap between the back yoke 16 and the sleeve 13 is narrow at the center of the side portion of the back yoke 16. Generation | occurrence | production can be prevented and the intensity | strength of the magnet 17 can be raised. Further, the magnet 17 can be easily incorporated inside the back yoke 16.

  In addition, as will be described in detail later, in this embodiment, on the outer peripheral surface of the sleeve 13, extended portions 13 a and 13 b that protrude toward the outer peripheral side are formed at the subject side end and the image sensor side end, respectively. ing. Here, the extended portions 13a and 13b are extended in a direction orthogonal to the optical axis X at both side positions sandwiching the lens 121 (lens barrel 12). When the sleeve 13 (moving lens body 3) configured in this way is arranged in the support 2, the expanded portions 13 a and 13 b are arranged inside the convex portion 16 a of the back yoke 16 between the adjacent magnets 17. . Here, the convex portion 16a extends in the optical axis direction, and the convex portion 16a is a movement that allows the expansion portions 13a and 13b to move in the optical axis direction when the movable lens body 3 moves in the optical axis direction. It functions as the path 16e. Further, when the moving lens body 3 is displaced in a direction (right and left direction or circumferential direction) orthogonal to the optical axis direction due to an impact or the like, the extended portion 13a comes into contact with the inner wall of the convex portion 16a of the back yoke 16, so Displacement in the left-right direction perpendicular to the optical axis direction of the moving lens body 3 and rotational displacement in the circumferential direction can be prevented. In addition, a stepped portion and a projection (not shown) for positioning when the spring members 14x and 14y are mounted may be formed on the subject side end portion and the imaging element side end portion of the sleeve 13.

(Detailed configuration of sleeve)
2A and 2B are a perspective view and a plan view, respectively, when the cover portion of the lens driving device to which the present invention is applied is removed. FIG. 3 is a view of the lens driving device 1 shown in FIG. 2 when viewed from directly above. In particular, FIG. 3A shows the external configuration, and FIG. 3B shows a cut surface when the lens drive device 1 is cut in the horizontal direction near the center of the height. FIG. 4 is an explanatory view schematically showing a state when the lens driving device 1 shown in FIG. 3 is cut in a predetermined direction. 4A corresponds to a longitudinal sectional view when the lens driving device 1 shown in FIG. 3 is cut along the one-dot chain line AA ′, and FIG. 4B shows the lens driving shown in FIG. This corresponds to a longitudinal sectional view when the apparatus 1 is cut along a dashed line BB ′. 3 and 4 show a state in which the lens barrel 12 is incorporated in the sleeve 13.

  As shown in FIG. 2A, in the lens driving device 1 according to the present embodiment, an extended portion 13 a that extends in a direction orthogonal to the optical axis X of the lens is formed on the outer periphery of the sleeve 13. The function of the extension unit 13a will be described in detail below.

  As shown in FIG. 3A, when the lens driving device 1 is viewed from above (from the front side), the shape of the case 11 is not square (or rectangular). This is due to the existence of a standard (standard called SMIA85) that must be followed when a camera module such as a lens, an actuator, a substrate including a sensor or a circuit element is fixed in a dedicated socket. This is because the socket can be easily attached and detached.

  As shown in FIG. 3B, the lens barrel 12, the sleeve 13, and the magnet 17 are surrounded by a back yoke 16, and the back yoke 16 has the same shape as the case 11. And the convex part 16a is formed in a part of the back yoke 16 located in the outer peripheral side of the magnet 17 or the coil 30, The above-mentioned expansion part 13a, 13b (FIG.1 (b) is formed by the inner side of this convex part 16a. ))) Is secured. Two extended portions 13a and 13b are formed on each of the subject side and the image sensor side so as to interpose a lens (lens barrel 12).

  In the moving lens body 3, the extension portions 13a and 13b on the subject side and the image sensor side have substantially the same outer peripheral shape when viewed from the optical axis direction. Therefore, hereinafter, the extension portion 13a side is the center. explain.

  In this embodiment, a contact portion 16b and a contact portion 16c that can contact the expansion portion 13a are formed inside the convex portion 16a. The contact portion 16b and the contact portion 16c are substantially orthogonal to each other, and the corner portion of the contact portion 16c with which the expanded portion 13a abuts when the sleeve 13 rotates is an R surface. In addition, in the expansion part 13a, the surface which contacts the inner wall of the convex part 16a of the back yoke 16 may be constituted by an R face or a square face.

  The left half of FIG. 4A shows a view when the sleeve 13 is at an infinite position (normal shooting position), and the right half of FIG. 4A shows the sleeve 13 in the macro position (close-up shooting). The figure when it is in (position) is shown. As shown in FIG. 4A, expansion portions 13a and 13b are formed on the sleeve 13, and when the sleeve 13 is in the normal photographing position, the expansion portion 13b on the rear side of the expansion portions 13a and 13b. The rear end surface 13 d comes into contact with the holder 19. On the other hand, when the sleeve 13 is at the macro photographing position, the front end surface 13c of the extension portion 13a comes into contact with the case 11. In this way, the sleeve 13 and the case 11 or the holder 19 abut on the outer peripheral side position away from the lens barrel 12, and the case 11 and the holder 19 function as contact portions for the expansion portions 13a and 13b, respectively. Therefore, the moving lens body 3 is not excessively displaced in the optical axis direction.

  As shown in FIG. 4B, the magnet 17 is interposed between the two front and rear spring members 14x and 14y. These spring members 14x and 14y restrict the movement of the sleeve 13, and can stop the sleeve 13 at a position that balances the electromagnetic force generated in the drive mechanism (coil 30 and the like). In the cross-sectional view shown in FIG. 4B, the rear end surface or the front end surface of the cylindrical body of the sleeve 13 is the holder regardless of whether the left half normal photographing position or the right half macro position. 19 and the case 11 are not in contact.

  Further, as shown in FIG. 5A, for example, when the sleeve 13 is displaced upward in the figure due to some impact or the like (see the arrow), the expansion portions 13a and 13b of the sleeve 13 contact the degree of the back yoke 16. It contacts the part 16b. And after contact | abutting, since it can prevent that the expansion part 13a is displaced to the radial direction outer side (direction orthogonal to the optical axis X) any more, the expansion part 13a and the contact part 16b function as a stopper. Have

  As shown in FIG. 5B, for example, when the sleeve 13 is displaced rightward in the drawing due to some impact or the like (see arrow), the expanded portions 13a and 13b of the sleeve 13 are the contact portions 16c of the back yoke 16. Abut. And after contact | abutting, since it can prevent that the expansion part 13a is displaced to the right direction any more, the expansion part 13a and the contact part 16c have a role as a stopper.

  The contact portion 16c also exhibits a detent function in the rotation direction of the sleeve 13. Specifically, as shown in FIG. 5C, for example, when the sleeve 13 is displaced clockwise by some impact or the like (see an arrow), the expanded portion 13a of the sleeve 13 It abuts against the contact portion 16c. And after contact | abutting, since it can prevent the expansion part 13a from rotating rightward any more, the expansion part 13a and the contact part 16c have a role as a stopper.

  A normal state in which no force is applied to the sleeve 13 is shown in FIG.

(Detailed configuration of spring member)
As shown in FIG. 1B, the lens driving device 1 is provided with spring members 14x and 14y for restricting the movement of the sleeve 13 based on the electromagnetic force when the driving mechanism generates an electromagnetic force. In this embodiment, the spring members 14x and 14y are formed in a gimbal spring shape.

  The spring members 14 x and 14 y are metal springs. First, the spring member 14 x disposed between the back yoke 16 and the holder 19, and the spring member 14 y disposed between the back yoke 16 and the case 11. Among these, the structure of the spring member 14y arrange | positioned between the back yoke 16 and the case 11 is demonstrated.

  In this embodiment, as shown in FIG. 2B, the spring member 14y includes four small annular outer coupling portions 141a, 141b, and 141c held between the back yoke 16 and the case 11 in the support body 2. 141d, a ring-shaped inner coupling portion 142 coupled to the front end of the sleeve 13, and four arm portions 143a, 143b, 143c coupling the inner coupling portion 142 and the outer coupling portions 141a, 141b, 141c, 141d. , 143d. The four outer connecting portions 141a to 141d are arranged at the four corners of the rectangular back yoke 16 (frame portion) constituting the support 2, and are small projections formed on the case 11 inside the outer connecting portions 141a to 141d. By inserting 112, the spring member 14 y is sandwiched between the case 11 and the back yoke 16. At this time, insulation is provided between the back yoke 16 and the spring member 14y. In addition, four magnets 17 (shown by alternate long and short dash lines) are respectively disposed at the four corners of the back yoke 16, and the four arm portions 143a to 143d are disposed so as to overlap with the magnet 17 in the optical axis direction. .

  Here, a part of the outer peripheral surface of the inner coupling portion 142 is indicated by a two-dot chain line in FIG. 2B formed by connecting the midpoints of the side wall surfaces constituting the back yoke 16. ) On the outer side (back yoke 16 side).

  Further, in the spring member 14y, the four arm portions 143a to 143d have a line-symmetric structure with respect to L1 that passes through the optical axis X and bisects the spring member 14y.

  Among these arm portions 143a to 143d, first, as shown in FIG. 2B, the arm portion 143a is connected to the inner connecting portion 142 via the inner connecting portion 144a, and to the outer connecting portion 141a. Are connected via an outer connection portion 149a.

  The arm portion 143a includes a meandering portion 145a in which a total of three linear or arc-shaped elongated portions 146a extending in the circumferential direction of the inner connecting portion 142 are connected in series by a folded portion 147a. Here, the three extending portions 146a extend substantially parallel to each other, and a plurality of the extending portions 146a are arranged in parallel in the radial direction. The inner connection portion 144a is wider than the width dimension of the meandering portion 145a. With this configuration, the radial rigidity of the spring member 14y can be increased.

  Further, in the plurality of extending portions 146a, a portion located on the radially inner side is longer than a portion located on the radially outer side. For this reason, the arm portion 141a has a substantially triangular outer peripheral contour shape having a base on the radially inner side and a vertex at the back of the corner. Therefore, although the arm part 141a is arrange | positioned in the narrow area | region, it has many extending | stretching parts 146a and the folding | returning parts 147a.

  The arm portions 143b to 143d are connected to the inner connecting portion 142 via the inner connecting portions 144b to 144d, and are connected to the outer connecting portions 141b to 141d via the outer connecting portions 149b to 149d. Since the structure of the meandering portions 145b to 145d is the same as that of the arm portion 143a, description thereof is omitted.

  In the spring member 14y configured as described above, in the arm portions 143b and 143d, the meandering portions 145b and 145d are not formed on the radially outer side of the inner connection portions 144b and 144d, but the radial direction of the inner connection portions 144b and 144d. It is formed at a position shifted from the outside to one side in the circumferential direction (clockwise CW side in FIG. 2B). Also, in the arm portions 143a and 143c, like the arm portions 143b and 143d, the meandering portions 145a and 145c are not formed on the radially outer sides of the inner connection portions 144a and 144c, and the radii of the inner connection portions 144a and 144c are not formed. It is formed at a position shifted from the outside in the direction to one side in the circumferential direction (counterclockwise CCW side in FIG. 2B). With this configuration, the extension portion 146a extending from the inner connection portion 144 can be made longer, so that the radial rigidity of the spring member 14y can be increased.

  Further, in this embodiment, in each of the plurality of arm portions 143a to 143d, the extension lines of the inner connection portions extend substantially parallel to each other on the region side that sandwiches the center position of the inner connection portion 142. With this configuration, the portions where the arm portions 143a to 143d impart spring properties to the movable lens body are dispersed in a plane orthogonal to the optical axis X, and the spring constant of the spring member 14y can be made constant. The vibration of the movable lens body 3 in the tilt direction can be efficiently suppressed.

  The spring member 14y configured as described above is biased toward the front end or the rear end of the sleeve 13 through the elastic force generated in the four arm portions 143a to 143d. In FIG. 2, only the spring member 14 y disposed at the front end of the sleeve 13 is focused for convenience of explanation, but the configuration is the same as that of the spring member 14 x disposed at the rear side of the sleeve 13. Therefore, the description of the spring member 14x disposed on the rear side of the sleeve 13 is omitted.

(basic action)
In the lens driving device 1 configured as described above, the moving lens body 3 is normally located on the image sensor side (image side). Specifically, the lower end surface (image side surface) of the sleeve 13 is in contact with the upper surface (front side surface) of the holder 19.

  In such a state, when a current in a predetermined direction flows through the coil 30, the coil 30 receives an upward (front) electromagnetic force. As a result, the sleeve 13 to which the coil 30 is fixed starts to move toward the subject side (front side). At this time, elastic forces that restrict the movement of the sleeve 13 are generated between the spring member 14y and the front end of the sleeve 13 and between the spring member 14x and the rear end of the sleeve 13, respectively. For this reason, when the electromagnetic force that attempts to move the sleeve 13 to the front side and the elastic force that restricts the movement of the sleeve 13 are balanced, the sleeve 13 stops. Further, when a current in the reverse direction is passed through the coil 30, the coil 30 receives a downward (rear) electromagnetic force.

  At that time, the sleeve 13 (moving lens body 3) can be stopped at a desired position by adjusting the amount of current flowing through the coil 30 according to the elastic force acting on the sleeve 13 by the spring members 14x and 14y.

  Furthermore, in this embodiment, since the spring members 14x and 14y in which a linear relationship is established between the elastic force (stress) and the displacement amount (strain amount) are used, the movement amount of the sleeve 13 and the current flowing through the coil 30 are used. The linearity between and can be improved. In addition, since the two spring members 14x and 14y are used, a large balance force is applied in the direction of the optical axis X when the sleeve 13 is stopped, and centrifugal force and impact force are applied in the direction of the optical axis X. Even if other forces such as these work, the sleeve 13 can be stopped more stably. Further, in the lens driving device 1, the sleeve 13 is not stopped by colliding with a collision material (buffer material) or the like, but is stopped using a balance between electromagnetic force and elastic force. Therefore, it is possible to prevent the occurrence of a collision sound.

(Main effects of this form)
As described above, according to the lens driving device 1 of the present embodiment, the sleeve 13 is displaced more than a predetermined distance (for example, rotated more than a predetermined angle as shown in FIG. 5C) due to an impact or the like. Can be prevented (see FIG. 5). In particular, the lens driving device 1 according to the present embodiment is provided with a stopper for rotating up, down, left, and right in one place (convex portion 16a), thereby reducing the manufacturing cost, simplifying the manufacturing process, and the lens driving device 1. Adapts to the overall miniaturization and brings practical benefits. Further, without providing a guide mechanism having a complicated shape as in the case of a conventional lens driving device, it is possible to add a detent function by simply forming the expansion portions 13a and 13b on the sleeve 13, and thus practicality. Can be increased.

  In addition, as compared with the conventional lens driving device, the extended portions 13a and 13b are in contact with the contact portions 16b and 16c (see FIG. 5) on the outer peripheral side, not in the vicinity of the lens. Therefore, even if wear powder is generated when the extended portions 13a and 13b come into contact with the contact portions 16b and 16c, the wear powder can be prevented from adhering to the sensor surface of the image sensor on the holder 19 side.

  Further, since the contact portion 16c of the back yoke 16 has an R surface where the expanded portions 13a and 13b abut, the amount of generated wear powder is reduced compared to the case where the portion is a rectangular surface. be able to.

  In addition, since the convex portions 16a of the back yoke 16 having the contact portions 16b and 16c formed on the inside are formed at two locations so as to interpose the lens, the projections 16a are more compact than when formed at one location. The effect can be enhanced. Further, the sleeve 13 is displaced (displaced) by a predetermined range or more in the left-right direction with respect to the optical axis direction of the lens due to an impact on the lens driving device 1, or the sleeve 13 is rotated by a predetermined angle or more in the rotation direction. Can be prevented.

  Further, in the lens driving device 1 according to the present embodiment, the movement of the sleeve 13 is restricted by the spring members 14x and 14y. However, the action of the expansion portion 13a and the contact portions 16b and 16c causes the spring members 14x and 14y to move. Deformation can be prevented. That is, if the sleeve 13 is displaced beyond a predetermined distance, the spring members 14x and 14y are likely to be plastically deformed. However, according to this embodiment, the occurrence of such a problem can be prevented.

  Furthermore, in this embodiment, the spring members 14x and 14y for supporting the movable lens body so as to be movable in the optical axis direction include four arm portions 143a between the outer connecting portions 141a to 141d and the inner connecting portion 142. The arm portion 143a includes a meandering portion 145a in which a plurality of extending portions 146a extending in the circumferential direction are connected in series by folded portions 147a. The same applies to the other arm portions 143b, 143c, and 143d. Further, the four arm portions 143a to 143d are arranged at the four corners of the substantially rectangular back yoke 16. As described above, by arranging the arm portions 143a to 143d at the four corners of the relatively large back yoke 16 in the space surrounded by the inner periphery of the back yoke 16 and the outer periphery of the moving lens body, the arm portions 143a are arranged. Compared with the structure which arrange | positions -143d in locations other than the four corners of the back yoke 16, the number of the folding | returning parts 147a can be increased to the extent that many extending | stretching parts 146a can be arrange | positioned. Also, by arranging the extending portions 146a along the circumferential direction of the moving lens body 3, a large number of the extending portions 146a can be arranged, and thus the same effect can be obtained. Therefore, it has excellent vibration resistance and shock resistance when the moving lens body 3 moves in a direction perpendicular to the optical axis direction or tilts in an oblique direction (tilt direction) with respect to the optical axis. Further, the arm portion 143a has sufficient rigidity to withstand the stress applied when the movable lens body 3 moves in a direction orthogonal to the optical axis direction or when tilted in an oblique direction with respect to the optical axis. The situation where ˜143d is plastically deformed can be surely avoided.

  Further, since the inner connection portions 144a to 144d are formed wider than the arm portions 143a to 143d, they are not damaged even if a large load is applied to the inner connection portions 144a to 144d. Further, when the inner connection portions 144a to 144d are formed wide, the stress when the moving lens body 3 moves in the direction orthogonal to the optical axis X or when tilted in the oblique direction with respect to the optical axis X is a meandering portion 145a. Since ˜145d is applied, stress such as when the moving lens body 3 moves in a direction orthogonal to the optical axis X or when tilted in an oblique direction with respect to the optical axis X can be efficiently absorbed.

[Modification of Embodiment 1]
FIG. 6 is a cross-sectional view of a lens driving device according to a modification of the first embodiment of the present invention. In the lens driving device 1 shown in FIG. 2, the back yoke 16, the magnet 17, and the coil 30 are considered as the magnetic circuit. However, like the lens driving device 1A shown in FIG. 6A, the inner yoke 21 is used as the magnetic circuit. You can add it. Thereby, magnetic flux can be induced in a desired direction (leakage magnetic flux can be reduced), and stable electromagnetic force can be obtained.

  Further, like the lens driving device 1B shown in FIG. 6B, the shape of the coil 30 may be deformed, and the coil 30 may be used as a stopper. That is, in the moving coil type lens driving device 1 </ b> B, the coil 30 moves together with the sleeve 13. Therefore, for example, when the sleeve 13 is displaced upward in the drawing due to some impact or the like, the coil 30 is also displaced, and the deformed portion 30a (an example of the expanded portion) of the coil 30 is the contact portion of the back yoke 16. It abuts on 16b. The same applies to the case where the sleeve 13 is displaced in the right direction (or left direction) or right rotation direction (or left rotation direction) in the drawing due to some impact or the like. The coil 30 replaces the stopper by the action of the deformed portion 30a of the coil 30 and the convex portion 16a (degree portion 16b or degree portion 16c).

  Although not shown in the figure, an extended portion 13a of the sleeve 13 may be provided so as to abut against the contact portion 16b of the back yoke 16. As described above, even when the coil 30 is deformed and the coil 30 is used as a stopper, even when the coil 30 is deformed and the stopper is formed by the extended portion 13a of the sleeve 13, the entire length of the coil can be obtained by deforming the coil. Therefore, the magnetic force is improved.

  In the lens driving device 1A shown in FIG. 6A, a modified example of the dotted frame Y is shown in FIG. According to the modification shown in FIG. 6C, when the expansion portion 13 a of the sleeve 13 is displaced in the right direction or the right rotation direction in the drawing, the contact portion that contacts the expansion portion 13 a is the contact amount of the magnet 17. Part 17g. Thus, even if the contact portion 17g is provided on the back yoke 16 (see the convex portion 16a), even if it is provided on the magnet 17, the case 11 and the holder 19 are provided. May be provided. That is, the contact portion that comes into contact with the expanded portion 13 a may be configured on the drive mechanism 5 on either the member disposed on the support body 2 side or the support body 2 side.

[Embodiment 2]
FIG. 7 is a plan view of the lens driving device according to Embodiment 2 of the present invention when the cover is removed. Since the basic configuration of the present embodiment is the same as that of the first embodiment, the overall configuration will be described with reference to FIGS. The description will be omitted.

  As shown in FIGS. 1A and 1B, the lens driving device 1 of the present embodiment is also provided between the back yoke 16 and the holder 19 and between the back yoke 16 and the case 11, as in the first embodiment. Spring members 14x and 14y are arranged between them. Since the basic configurations of the spring members 14x and 14y are the same, the configuration of the spring member 14y disposed between the back yoke 16 and the case 11 will be described.

  As shown in FIG. 7, the spring member 14y includes four small annular outer coupling portions 141a, 141b, and 141c that are held between the back yoke 16 and the case 11 in the support 2 as in the first embodiment. 141d, a ring-shaped inner coupling portion 142 coupled to the front end of the sleeve 13, and four arm portions 143a, 143b, 143c coupling the inner coupling portion 142 and the outer coupling portions 141a, 141b, 141c, 141d. , 143d. Also in this embodiment, four magnets 17 (shown by alternate long and short dash lines) are respectively disposed at the four corners of the back yoke 16, and the four arm portions 143a to 143d are disposed so as to overlap with the magnet 17 in the optical axis direction. Has been. Further, a part of the outer peripheral surface of the inner connecting portion 142 is outside the virtual quadrangle S (indicated by a two-dot chain line in FIG. 7) formed by connecting the midpoints of the side wall surfaces constituting the back yoke 16. It is located on the back yoke 16 side.

  In this embodiment, the arm portion 143a is connected to the inner connecting portion 142 via the inner connection portion 144a, and is connected to the outer connecting portion 141a via the outer connection portion 149a. Further, the arm portion 143a includes a meandering portion 145a in which a total of three linear or arc-shaped elongated portions 146a extending in the circumferential direction of the inner connecting portion 142 are connected in series by a folded portion 147a. The three extending portions 146a extend substantially parallel to each other, and a plurality of the extending portions 146a are arranged in parallel in the radial direction. The inner connection portion 144a is wider than the width dimension of the meandering portion 145a. Similarly to the arm portion 143a, the arm portions 143b to 143d are connected to the inner connecting portion 142 via the inner connecting portions 144b to 144d, and the outer connecting portions 141b to 141d are connected to the outer connecting portions 149b to 149d. Since the structure of the meandering portions 145b to 145d is the same as that of the arm portion 143a, the description thereof is omitted.

  In the spring member 14y configured as described above, in this embodiment, the four arm portions 143a to 143d are formed to be substantially rotationally symmetric about the optical axis X. That is, if one arm part is rotated by a predetermined angle, for example, about 90 °, with respect to the optical axis X, it overlaps with the other arm part.

  A similar spring member 14 x is also arranged on the rear side of the sleeve 13, but each arm portion in the spring member 14 x is also formed substantially rotationally symmetric about the optical axis X. Further, since the two spring members 14x and 14y are arranged in the same direction, the arm portions 143a to 143d of the spring member 14y and the arm portion of the spring member 14x are substantially rotationally symmetric with respect to the optical axis X. Is formed.

  If comprised in this way, even when the arm parts 143a-143d deform | transform when the movable lens body 3 moves to an optical axis direction, all the arm parts 143a-143d will deform | transform similarly. Accordingly, since there is only a narrow gap around the moving lens body 3, the moving lens body 3 does not tilt even if the shapes of the arm portions 143a to 143d are restricted. Further, when the moving lens body 3 moves in the optical axis direction, it is possible to adopt a configuration in which the moving lens body 3 is rotated in the circumferential direction as long as the aberration of the lens does not become a problem.

[Embodiment 3]
FIG. 8 is a cross-sectional view of the lens driving apparatus according to Embodiment 3 of the present invention. In the lens driving device 1 shown in FIG. 2, as shown in FIG. 3A, when the lens driving device 1 is viewed from above (from the front side), the shape of the case 11 is not square (or rectangular). Although designed based on a standard (standard called SMIA85), in the present embodiment, a case where the shape of the case 11 is a square (or a rectangle) will be described.

  Like the lens driving device 1C shown in FIG. 8A, the contact portion 16b is provided in the back yoke 16 so as to come into contact with the extended portion 13a of the sleeve 13 along the inner peripheral surface of the case 11 formed by a plane. You may do it.

  Further, as in the lens driving device 1D shown in FIG. 8B, the flat portion 16d formed on the outer peripheral surface of the back yoke 16 on which the contact portion 16b is formed and the flat portion of the case 11 are flush with each other. You may comprise.

  Further, as in the lens driving device 1E shown in FIG. 8C, a magnet 17 having a contact portion 17a is disposed along the inner peripheral surface of the case 11 formed by a plane, and a sleeve is provided on the contact portion 17a. You may comprise so that the 13 expansion parts 13a may hit.

  In any of the above-described embodiments, the outer shapes of the lens driving devices 1C to 1E are square (or rectangular), so that they can be easily incorporated into devices.

[Other embodiments]
In the above embodiment, the number of magnets 17 is four, and one magnet 17 is arranged at each of the four corners of the back yoke 16. However, in the present invention, the number of magnets 17 is two, and the back yoke is provided. You may employ | adopt the structure each arrange | positioned in the four corners among 16 corners which oppose. Similarly, in the spring members 14x and 14y, a configuration may be adopted in which the number of arm portions is two and the arm portions are arranged at opposing corner portions of the four corners of the back yoke 16. At this time, the magnet 17 and the arm part may be arranged so as to overlap with each other in the optical axis direction, or the arm part may be arranged at a position different from the place where the magnet 17 is arranged.

  In the above embodiment, the outer periphery of the back yoke 16 is substantially rectangular. However, in the present invention, the outer periphery of the back yoke 16 is formed by a plurality of surfaces parallel to the tangent line of the outer periphery of the moving lens body. If it is, it is arbitrary. Accordingly, the virtual polygon formed by connecting the midpoints of the side wall surfaces constituting the back yoke 16 is not limited to a square (see FIG. 2B).

  In the present invention, when a virtual regular square is assumed on the basis of the closest distance between the outer circumference of the movable lens body and the inner circumference of the back yoke 16, the midpoint of each side of the virtual regular square is You may employ | adopt the structure arrange | positioned on the outer side (back yoke side) rather than at least one side of the tied square.

(A), (b) is the external view and the disassembled perspective view which respectively looked at the front of the lens drive device concerning Embodiment 1 of this invention from diagonally upward. (A), (b) is the perspective view when a cover of the lens drive device to which this invention is applied is removed, respectively, and a top view. It is a figure when the lens drive device to which the present invention is applied is viewed from directly above. It is explanatory drawing which shows typically a mode that the lens drive device to which this invention was applied was cut | disconnected in the predetermined direction. It is explanatory drawing for demonstrating the effect | action of an expansion part and an expansion part in the lens drive device to which this invention is applied. It is a cross-sectional view of a lens driving device according to another embodiment of the present invention. In the lens drive device which concerns on Embodiment 2 of this invention, it is a top view when a cover part is removed. It is a cross-sectional view of the lens driving device according to Embodiment 3 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A-1E Lens drive device 11 Case 12 Lens barrel 13 Sleeve 14x, 14y Spring member 16 Back yoke 17 Magnet 18 Plate-shaped cover (cover part)
19 Holder 30 Coil 21 Inner yokes 141a, 141b, 141c, 141d Outer connecting part 142 Inner connecting parts 143a, 143b, 143c, 143d Arm parts 145a, 145b, 145c, 145d Serpentine part 146a Linear part (extension part)
147a Folded part

Claims (12)

A moving lens body that holds the lens, a support that supports the moving lens body in a direction of the optical axis of the lens via a spring member, and a drive mechanism that drives the moving lens body in the direction of the optical axis. A lens driving device having:
The support includes a polygonal cylindrical frame that surrounds the moving lens body,
The spring member includes an outer connecting portion connected to the support, an inner connecting portion connected to the moving lens body, and an arm portion connected to the inner connecting portion and the outer connecting portion.
The arm portion includes a meandering portion in which a plurality of extending portions are connected in series by folded portions, and a plurality of corners formed by an outer peripheral surface of the moving lens body and a side wall surface adjacent to the frame portion. A lens driving device, wherein the lens driving device is disposed in at least two of the sections.   The lens driving device according to claim 1, wherein in the meandering portion, the plurality of extending portions extend in a circumferential direction.   3. The lens driving device according to claim 2, wherein in the meandering portion, three or more extending portions are arranged in parallel in the radial direction.   The lens driving device according to claim 3, wherein the plurality of extending portions include extending portions extending substantially parallel to each other.   5. The lens driving device according to claim 2, wherein in the plurality of extending portions, a portion located on the radially inner side is longer than a portion located on the radially outer side.   The lens driving device according to claim 5, wherein the arm portion has a substantially triangular outer peripheral contour shape having a base on a radially inner side and a vertex on the back of the corner portion.   The meandering portion is formed in a region shifted in a circumferential direction from a portion located radially outside a connecting portion between the inner connecting portion and the arm portion. The lens driving device according to one item.   The lens driving device according to any one of claims 1 to 7, wherein a width dimension of a connection portion between the inner coupling part and the arm part is wider than a width dimension of the meandering part. When viewed from the optical axis direction,
The outer peripheral shape of the moving lens body is circular,
9. The outer peripheral surface of the movable lens body protrudes to the outer peripheral side from at least one side of a virtual polygon connecting the centers of adjacent sides in the frame part. The lens driving device according to Item. When viewed from the optical axis direction,
The lens driving device according to claim 9, wherein an outer peripheral surface of the moving lens body protrudes outward from any side of the virtual polygon.   The lens driving device according to any one of claims 1 to 10, wherein magnets constituting the driving mechanism are respectively disposed at at least two of the plurality of corner portions.   The lens driving device according to claim 11, wherein the arm portion and the magnet are arranged so as to overlap each other in at least two of the plurality of corner portions in the optical axis direction.

Images