JP2006079072A - Autofocus actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an autofocus actuator having a yoke having a sufficient bonding area to a leaf spring. <P>SOLUTION: The autofocus actuator is provided with a yoke 320 that comprises an inner cylindrical portion 321 forming an insertion bore into which a hollow body portion of a holder is inserted and an outer cylindrical portion 322 provided outside of the inner cylindrical portion with a prescribed spacing via a connection part. Four tab-shaped portions 325 forming a continuous surface with an end surface of the outer cylindrical portion 322 and extending outwards of the outer cylindrical portion are integrally formed with the end surface of the outer cylindrical portion. Moreover, a concave portion 327 is formed between the adjacent tab-shaped portions 325. This assures that the tab-shaped portion 325 can make contact with the leaf spring in a broader area, thus enabling the leaf spring to be reliably bonded to the york 320. Moreover, the yoke 320 can be aligned with ease by disposing a part of a support frame within the concave portion 327 formed between the adjacent tab-shaped portions 325. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an autofocus actuator, and more particularly to an autofocus actuator that can be used in a small electronic device with a camera such as a digital camera or a mobile phone.

  In a digital camera or the like, an actuator capable of moving a lens in the optical axis direction is used for the purpose of autofocus and zoom. This type of actuator moves the lens in the direction of the optical axis by the interaction between the magnetic field generated by the current flowing in the coil and the magnetic field generated by the permanent magnet. Recently, even in cameras mounted on mobile phones, the number of pixels of the image sensor has been changed to megapixels of 1 million pixels or more, so that an autofocus function has been required.

  As a conventional autofocus actuator, one disclosed in Japanese Patent Application Laid-Open No. 2003-295033 is known. This actuator generally supports a front lens, a front support frame that supports the front lens, a front coil attached to the front support frame, a front spring attached to the front support frame, a rear lens, and a rear lens. A rear support frame, a rear coil attached to the rear support frame, a rear spring attached to the rear support frame, a magnet, a magnet support, and a yoke. The front coil is disposed in the outer gap between the magnet and the yoke. The rear coil is disposed in the inner gap between the magnet and the yoke. By applying a current to the front coil, the front lens can be moved to a position that balances the elastic force of the front spring. Further, by applying a current to the rear coil, the rear lens can be moved to a position that balances the elastic force of the rear spring.

  The conventional actuator has a structure in which power is supplied to the coil via a front spring and a rear spring. Accordingly, it is necessary to provide coil and power supply electrode portions on the front spring and the rear spring, respectively. In order to form such an electrode portion, it is necessary to bend the front spring and the rear spring. Therefore, there arises a problem that the yield and productivity of the spring are lowered.

  In addition, since the coil and the conductive wire are directly soldered to the spring itself to establish conduction, it is necessary to insulate the spring from other components. This causes a problem that the number of parts of the actuator increases.

  Furthermore, since the front spring and the rear spring have different shapes, there arises a problem that the manufacturing cost of the spring increases.

  In order to solve the above problems, the present inventors have devised the autofocus actuator shown in FIGS.

JP 2003-295033 A

  The problems in the conventional actuator can be solved by the autofocus actuator shown in FIGS. However, this autofocus actuator uses a pair of leaf springs (gimbal springs), and these leaf springs are fixed by an adhesive while being sandwiched between both end surfaces of the yoke and the corresponding support frames. ing. Therefore, although details will be described later, since one end surface of the yoke is an end surface of the outer cylindrical portion of the yoke, the bonding area of the portion to be bonded to the leaf spring is extremely small, and sufficient bonding strength between the yoke and the leaf spring is obtained. I can't. As a result, when any impact is applied to the autofocus actuator, the leaf spring may come off or shift. Therefore, it is desirable to avoid such problems as much as possible.

Further, in the actuator of Patent Document 1, a jig or the like is required for positioning the yoke and the support frame during assembly, which complicates the assembly process. It is therefore desirable to avoid such problems.
The present invention has been made in view of these demands, and an object thereof is to provide an autofocus actuator having a yoke having a large adhesion surface with a leaf spring.

  In order to achieve the above object, an autofocus actuator according to the present invention is fixed to the holder so as to be positioned around the cylindrical portion of the holder, and a holder having a cylindrical portion to which a lens is attached at one end. A pair of leaf springs that are provided on both sides of the cylindrical portion of the holder in the optical axis direction and support the holder so as to be displaceable in the optical axis direction in a state of being positioned in the radial direction. The lens attached to the holder can be adjusted in the optical axis direction by the interaction between the magnetic field generated in the coil and the magnetic field of the permanent magnet when the coil is energized. And an actuator for autofocusing, wherein the yoke is a leaf spring positioned on the other end side of the cylindrical portion of the holder It has abutting end faces, characterized by being formed integrally with adhesive surface for adhering holding the plate spring to the end face.

  Further, in the autofocus actuator of the present invention, the yoke has a predetermined interval via an inner cylindrical portion forming an insertion hole through which the cylindrical portion of the holder is inserted, and a connecting portion outside the inner cylindrical portion. It is preferable that the end surface of the yoke is an end surface of the outer cylinder portion. Further, the bonding surface is formed from at least one tab-shaped portion integrally formed on the end surface of the outer cylinder portion of the yoke so as to form a continuous surface with the end surface and to extend to the outside of the outer cylinder portion. It is preferable to be configured.

  In the autofocus actuator of the present invention, it is preferable that four tab-like portions are provided on the end surface of the outer cylinder portion of the yoke at intervals of approximately 90 degrees.

  In the autofocus actuator according to the present invention, it is preferable that the outer edge of each of the tab-like portions substantially coincides with a tangent of an end surface of the outer cylindrical portion of the yoke.

  Furthermore, the autofocus actuator of the present invention is preferably formed so that the tab-shaped portion has a concave portion between adjacent tab-shaped portions.

  In the autofocus actuator of the present invention, the adhesive surface extends around the end surface of the outer cylinder portion of the yoke so as to form a continuous surface with the end surface and extend to the outside of the outer cylinder portion. It is preferable that it is comprised from the flange part formed in this.

  According to the autofocus actuator of the first aspect, the leaf spring located on the other end side of the cylindrical portion of the holder is bonded to the end surface and the bonding surface of the yoke. Therefore, it is possible to bond the leaf spring to the yoke more stably and surely than when it is bonded only to the end surface of the yoke.

  According to the autofocus actuators of the second and third aspects, the yoke having the tab-like portion can be easily manufactured by integral molding.

  According to the autofocus actuator of the fourth aspect, the leaf spring can be bonded to the yoke stably and reliably by the four tab-like portions.

  According to the autofocus actuator of the fifth aspect, it is possible to increase the bonding surface of the yoke to which the leaf spring is bonded while maintaining the same diameter as the yoke without the tab-shaped portion.

  According to the autofocus actuator of the sixth aspect, the pillar portion of the support frame can be positioned in the recess, and the yoke can be positioned with respect to the support frame.

  According to the autofocus actuator of the seventh aspect, the yoke having the flange portion can be easily manufactured by integral molding. Further, the leaf spring is bonded to the end face of the yoke and the flange portion. Therefore, it is possible to bond the leaf spring to the yoke more stably and surely than when it is bonded only to the end surface of the yoke.

  The above-described and other configurations, operations, and effects of the present invention will become more apparent from the following description of the basic configuration and preferred embodiments with reference to the drawings.

  Hereinafter, based on the attached drawings, first, an autofocus actuator which is a premise of the present invention and proposed by the present inventor will be described.

  FIG. 1 is a perspective view of the appearance of an autofocus actuator. FIG. 2 is an exploded perspective view of the autofocus actuator shown in FIG. FIG. 3 is a schematic cross-sectional view of the autofocus actuator shown in FIG.

  This autofocus actuator (hereinafter also simply referred to as “actuator”) 1 includes a cylindrical portion 11 having a lens assembly 100 attached to one end thereof and a cylinder thereof, as schematically shown in FIGS. A holder 10 having a flange portion 12 provided on the outer periphery of the other end of the cylindrical portion 11; a coil 20 fixed to the flange portion 12 at a distance from the periphery of the cylindrical portion 11 of the holder 10; An inner cylinder part 31 having an insertion hole 35 through which the cylindrical part 11 is inserted, an outer cylinder part 32 provided at a predetermined interval outside the inner cylinder part 31, and the inner cylinder part 31 and the outer cylinder part 32. The holder 10 has a connecting portion 34 (see FIGS. 4 and 5) in which the end opposite to the flange portion 12 is integrally connected, and a predetermined interval between the inner cylindrical portion 31 and the outer cylindrical portion 32 is provided. Configured to accommodate coil 20 in space A plurality of cylindrical yokes 30 arranged to face the coil 20 at intervals with a magnet mounting surface 33 (see FIG. 4) on the inner peripheral surface of the outer cylindrical portion 32 of the cylindrical yoke 30. A permanent magnet 40; a magnetic member 50 arranged to connect the plurality of permanent magnets 40 in contact with the surface opposite to the connecting portion 34 of the cylindrical yoke 30 of the plurality of permanent magnets 40; A pair of leaf springs comprising upper leaf spring 60U and lower leaf spring 60L which are provided on both sides of the cylindrical portion 11 of the holder 10 so as to be displaceable in the optical axis direction with the holder 10 positioned in the radial direction. 60; a stopper 70 attached to the holder 10 so that the upper plate spring 60U is clamped between the holder 10 and the plate spring 60. The optical axis direction of the yoke 30 A cover 80 and a base 85 forming a pair of support frames each having an opening 80a, 85a at least in a portion corresponding to the lens assembly 100 attached to the holder 10 and sandwiched between the end surfaces; and a lower leaf spring 60L And a sheet-like electrode 90 provided to supply power to the coil 20.

  In the actuator as described above, the lens assembly 100 includes a plurality of lenses (not shown). In other words, the plurality of lenses are attached to one end of the cylindrical portion 11. However, the position where the plurality of lenses (lens assembly 100) are attached to the cylindrical portion 11 is not limited thereto.

  Hereinafter, details of each component will be described. In the present specification, the terms “upper” and “lower” are used as appropriate. In the description of each member, the direction of the arrow shown in FIG. 2 is the upward direction, and the opposite direction of the arrow is the downward direction.

  The holder 10 is a molded product made of synthetic resin. A cylindrical tubular portion 11 to which the lens assembly 100 is attached from one end side (upper end side) and a circular flange portion 12 provided integrally on the outer periphery of the other end side (lower end side) of the tubular portion 11. Have. As shown in FIG. 3, the cylindrical portion 11 of the holder 10 is hollow. On the inner peripheral surface of the cylindrical portion 11, a female screw portion for screwing with a male screw portion formed on the outer periphery of the lens assembly 100 is formed. Further, a step portion 12a for bonding the coil 20 in a state where the coil 20 is positioned with respect to the holder 10 is provided on the peripheral portion of the upper surface (surface on the cylindrical portion 11 side) of the flange portion 12 (see FIG. 3). ). Further, a ring-shaped convex portion (step portion) 15 for positioning the lower leaf spring 60 </ b> L with respect to the holder 10 is formed substantially concentrically on the lower surface of the flange portion 12. On the convex portion 15, three thin protrusions 13 extending in a direction parallel to the optical axis are formed integrally with the convex portion 15 at equal intervals.

  As described above, the coil 20 is fixed to the step portion 12 a on the upper surface of the flange portion 12 of the holder 10 so as to be spaced from the periphery of the cylindrical portion 11 of the holder 10. The coil 20 uses a copper wire whose surface is coated. Further, the coil 20 is formed by different numbers of turns in which a 10-turn layer and a 9-turn layer of copper wire are alternately stacked. The cross section of the coil 20 is a circular air-core coil. Further, the coil 20 is wound so that the leading portions 21 at both ends of the winding are positioned on the flange portion 12 side. Such an air core coil is fixed to the step portion 12a on the upper surface of the flange portion 12 of the holder 10 with an adhesive. In addition, the coil 20 is not limited to the above air core coil, For example, the coil may be wound around the cylindrical part 11 directly.

  As shown in FIG. 4, the yoke 30 is provided with a cylindrical inner cylinder part 31 having an insertion hole 35 through which the cylindrical part 11 of the holder 10 is inserted, and outside the inner cylinder part 31 at a predetermined interval. It has the cylindrical outer cylinder part 32 and the connection part 34 which the edge part on the opposite side to the flange part 12 of the holder 10 of the inner cylinder part 31 and the outer cylinder part 32 connects integrally. The coil 20 is accommodated in a space at a predetermined interval between the inner cylinder portion 31 and the outer cylinder portion 32 of the yoke 30.

  The yoke 30 is made of, for example, a nickel-plated iron surface that is a magnetic material. The cylindrical portion 11 of the holder 10 is inserted into the insertion hole 35 of the inner cylindrical portion 31 so as to be movable in the optical axis direction. Therefore, the diameter of the insertion hole 35 of the inner cylinder part 31 is formed so as to be larger than the diameter of the outer peripheral surface of the cylindrical part 11 of the holder 10 and smaller than the diameter of the peripheral part of the flange part 12 of the holder 10. .

  Further, as shown in FIGS. 2 to 4, the height in the optical axis direction of the inner cylinder portion 31 with respect to the connecting portion 34 is formed to be lower than the height in the optical axis direction of the outer cylinder portion 32. .

  A plurality (four pieces) of permanent magnets 40 are arranged on the magnet mounting surface 33 on the inner peripheral surface of the outer cylindrical portion 32 of the cylindrical yoke 30 so as to face the coil 20 with a space therebetween. The magnet mounting surface 33 is not limited to being provided on the inner peripheral surface of the outer cylindrical portion 32 of the yoke 30 as described above, and may be provided on the outer peripheral surface of the inner cylindrical portion 31.

  Each of these permanent magnets 40 is formed of a permanent magnet that is curved in an arc shape of approximately 90 degrees so as to follow the shape of the circular magnet mounting surface 33. The permanent magnet 40 is a neodymium magnet. For example, the curved surface on the side abutting on the magnet mounting surface 33 is magnetized so as to be the S pole and the curved surface substantially opposite to the curved surface is the N pole. By attaching these arc-shaped permanent magnets 40 to the cylindrical yoke 30, the outer peripheral surface of the inner cylindrical portion 31 of the yoke 30 becomes an S pole. Thereby, the magnetic field which goes to the inner cylinder part 31 from the permanent magnet 40 curved in circular arc shape is formed. When the coil 20 is energized, a force in the optical axis direction acts on the coil 20 due to the interaction between the magnetic field generated by the current flowing through the coil 20 and the magnetic field formed by the permanent magnet 40. Thereby, the holder 10 (that is, the lens assembly 100) can be moved in the optical axis direction. The number of permanent magnets is not limited to four pieces, and a plurality of other permanent magnets may be used. The permanent magnet may be a single C-shaped permanent magnet, for example.

  By the way, in the yoke 30 as described above, as shown by the arrow in FIG. 5, the magnetic flux leaks downward between the adjacent permanent magnets 40 at the open portion opposite to the connecting portion 34 of the cylindrical yoke 30. End up. In order to prevent such leakage of magnetic flux, it is desirable to provide magnetic flux leakage prevention means on the yoke 30 to increase the driving force of the holder 10.

  As a means for preventing the leakage of magnetic flux, the magnet connected to the permanent magnet 40 while being in contact with the lower end surface of the permanent magnet 40, that is, the surface opposite to the surface in contact with the connecting portion 34 of the cylindrical yoke 30. A member 50 is arranged.

  By providing the magnetic member 50, the magnetic flux leaking downward is reduced as shown in FIG. Thereby, the magnetic flux which goes to the inner cylinder part 31 of the cylindrical yoke 30 from the permanent magnet 40 increases. In this actuator 1, a circular ring-shaped magnetic member 50 as shown in FIG. 7 is attracted to the permanent magnet 40, and the magnetic member 50 and the permanent magnet 40 are further fixed with an adhesive. As shown in FIG. 6, the width of the ring-shaped magnetic member 50 is equal to the radial thickness of the permanent magnet 40 curved in an arc shape. Thereby, arrangement | positioning of the coil 20 accommodated in the yoke 30 is not prevented. Further, the bottom surface of the ring-shaped magnetic member 50 is positioned above the end surface of the outer cylindrical portion 32 of the yoke 30 in a state where the magnetic member 50 is attached to the permanent magnet 40. Thereby, attachment of the lower leaf | plate spring 60L adhere | attached on the end surface of the outer cylinder part 32 of the yoke 30 is not prevented. In addition, the bottom surface of the magnetic member 50 may be configured to have the same size as the end surface of the outer cylindrical portion 32 of the yoke 30 in the optical axis direction, and the magnetic member 50 may be attached to the lower end surface of the permanent magnet 40. In this case, the bottom surface of the magnetic member 50 can be used as an adhesive surface with the lower leaf spring 60L.

  Further, the shape of the corner formed by the magnet mounting surface 33 and the connecting portion 34 of the yoke 30 may be different from the shape of the corresponding corner of the permanent magnet 40. Therefore, the corresponding surface of the permanent magnet 40 may not come into surface contact with the magnet mounting surface 33 of the yoke 30, resulting in a decrease in magnetic efficiency. In such a case, by inserting another magnetic member 50 between the connecting portion 34 of the yoke 30 and the upper surface of the permanent magnet 40, the shape of the corner portion formed by the magnet mounting surface 33 of the yoke 30 and the connecting portion 34 is obtained. The permanent magnet 40 can be brought into surface contact with the magnet mounting surface 33 of the yoke 30 without being affected.

  In the actuator 1, the cold rolled steel plate is used for the magnetic member 50. However, the magnetic member 50 is not limited to this, and may be formed of a magnetic material made of iron, nickel, cobalt, and alloys thereof.

  Similarly, when using one C-shaped permanent magnet, for example, the magnetic member 50 is disposed in contact with the lower end surface of the permanent magnet 40. Thereby, the magnetic flux which leaks below can be reduced between the end surfaces of the circumferential direction which a C-shaped permanent magnet faces.

  As shown in FIG. 8, the leaf spring 60 (upper leaf spring 60U, lower leaf spring 60L) is made of a thin metal plate. The upper leaf spring 60U and the lower leaf spring 60L connect the inner ring portion 61, the outer ring portion 62 provided at a predetermined interval from the inner ring portion 61, and the inner ring portion 61 and the outer ring portion 62, respectively. And a plurality of connecting portions 63. When a load is applied to the inner ring portion 61 with the outer ring portion 62 fixed, the connecting portion 63 is elastically deformed. Thereby, in a state where the holder 10 to which the inner ring portion 61 is bonded is positioned in the radial direction (that is, in a state where the displacement of the holder 10 in the radial direction is limited), the upper leaf spring 60U and the lower leaf spring 60L are 10 is supported so as to be displaceable in the optical axis direction.

  A step 16 for positioning the upper leaf spring 60U with respect to the holder 10 during assembly is formed on the upper surface of the holder 10 (see FIG. 2). The cross-sectional shape of the step portion 16 has a shape corresponding to the inner peripheral edge of the inner ring portion 61. The inner ring portion 61 of the upper leaf spring 60U is placed on the upper surface of the holder 10 in a state of fitting with the step portion 16, and the stopper 70 is further mounted thereon. As a result, the inner ring portion 61 is bonded to the holder 10 while being sandwiched between the upper surface of the holder 10 and the lower surface of the stopper 70. Further, the outer ring portion 62 is bonded to the cover 80 and the yoke 30 while being sandwiched between the lower surface of the cover 80 and the upper surface of the connecting portion 34 of the yoke 30.

  As described above, the step portion 15 for positioning the lower leaf spring 60L is also formed on the lower surface of the flange portion 12 during assembly. The cross-sectional shape of the step portion 15 has a shape corresponding to the inner peripheral edge of the inner ring portion 61. The inner ring portion 61 is bonded in a state of being positioned with respect to the holder 10. The outer ring portion 62 is bonded to the base 85 and the yoke 30 while being sandwiched between the end surface of the outer cylinder portion 32 of the cylindrical yoke 30 and the upper surface of the base 85.

  As shown in FIG. 3, the sheet electrode 90 is provided between the lower leaf spring 60 </ b> L and the base 85 in order to supply power to the coil 20. As shown in FIG. 9, the sheet-like electrode 90 is made of a polyimide sheet material. The sheet-like electrode 90 includes a ring-shaped portion 91 formed in a substantially circular ring shape, and an extending portion 92 that extends radially outward from the ring-shaped portion 91.

  Two terminal portions 93 made of copper are provided on one surface of the sheet-like electrode 90 from the extending portion 92 to the ring-shaped portion 91. In the ring-shaped portion 91, a dummy terminal portion 95 for soldering a dummy wire 23 described later is provided between the tips of the two terminal portions 93.

  Furthermore, an adhesive layer (not shown) for bonding the sheet electrode 90 to the lower surface of the outer ring portion 62 of the lower leaf spring 60L is provided on the other surface of the sheet electrode 90, and the ring portion 91 extends. The portion 92 is provided in the vicinity of the connection portion with the ring-shaped portion 91 and in the vicinity of the distal end portion of the extension portion 92.

  Further, the extending portion 92 extends to the outside of the support frame through an insertion hole 88 of the base 85 described later and is connected to a sensor substrate (not shown). In order to insert the extension 92 into the insertion hole 88, it is necessary to bend the extension 92 approximately 90 degrees with respect to the ring-shaped portion 91. In order to prevent the terminal portion 93 from being damaged by this bending, a cover film 94 made of polyimide is provided on the terminal portion 93.

  Electric power can be supplied to the coil 20 by soldering the tips of the two lead portions 21 of the coil 20 to the two terminal portions 93 provided on the ring-shaped portion 91 of the sheet-like electrode 90. However, undesired contact between the drawing portion 21 and other members caused by the displacement of the holder 10 and stress concentration occur near the soldered tip. Therefore, as shown in FIG. 10, the lead portions 21 on both sides of the winding of the coil 20 are wound around two of the three thin protrusions 13 provided on the step portion 15 on the lower surface of the flange portion 12 of the holder 10. Next, the leading end of the lead portion 21 is connected to the terminal portion 93 of the sheet electrode 90 via the soldering portion 22.

  Each of the protrusions 13 has a cylindrical shape having a height that does not contact an upper surface of a bottom plate portion 86 of the base 85 described later in an assembled state.

  The lead portion 21 extends from the coil 20 to the lower surface side of the flange portion 12 through a recess 14 (see FIG. 12) provided on the edge portion of the flange portion 12. Next, each of the drawer portions 21 is wound around the protrusion 13 near the recess.

  The lead-out portion 21 between the protrusion 13 and the soldering portion 22 is attached with a slack so that no tensile stress is generated in the lead-out portion 21 even when the holder 10 is displaced.

  Furthermore, in the actuator 1 described above, as shown in FIG. 11, the portion where the lead portion 21 is wound around the protrusion 13 of the holder 10 and the solder where the tip of the lead portion 21 is soldered to the terminal portion 93 of the sheet-like electrode 90. A stress relaxation agent 24 is provided so as to wrap around the attaching portion 22. Thereby, it is possible to prevent stress from concentrating on a part of the drawer portion 21.

  Furthermore, as shown in FIG. 12, three protrusions 13 are provided on the lower surface of the flange portion 12 at substantially equal intervals. The three protrusions 13 are inserted into the positions of substantially semicircular recesses 66 (see FIG. 8) at the inner edge of the inner ring portion 61 of the lower leaf spring 60L that is bonded to the lower surface of the flange portion 12, respectively.

  As described above, the lead portion 21 of the coil 20 is wound around two of the three protrusions 13. The remaining one is provided with balance holding means.

  This balance holding means includes a dummy wire 23 using the same wire as the winding of the coil 20. One end of the dummy wire 23 is wound around the protrusion 13, and the other end is soldered to the dummy terminal portion 95 of the sheet-like electrode 90. Thereby, the balance of the weight of the holder 10 can be maintained, and the holder 10 can be displaced in the optical axis direction in a stable posture.

  The dummy wire 23 is also provided with a stress relaxation agent 24 so as to wrap the portion wound around the protrusion 13 and the soldered portion of the dummy wire 23. Thereby, it is possible to prevent stress from being concentrated when part of the dummy wire 23 is inserted, and to maintain the balance of the weight of the holder 10.

  The actuator 1 is not limited to using the sheet electrode 90 as described above. For example, a terminal portion that is connected to the power source portion via an insulating material is formed on a part of the lower surface (surface opposite to the holder 10) of the outer ring portion 62 of the lower leaf spring 60L that does not displace with the displacement of the holder 10. It may be formed and the tip of the lead portion 21 of the coil 20 may be connected to the terminal portion.

  As shown in FIG. 13, the stopper 70 is made of a synthetic resin formed in a ring shape, and is bonded in a state where the inner ring portion 61 of the upper leaf spring 60 </ b> U is sandwiched between the holder 10.

  A part of the edge of the three openings 71 is positioned so as to coincide with the shape of the substantially semicircular recess 65 (see FIG. 8) at the outer edge of the inner ring part 61 of the upper leaf spring 60U. Assembled. Therefore, the clearance between the cylindrical portion 11 of the holder 10 and the inner cylindrical portion 31 of the yoke 30 can be confirmed through the opening 71 and the substantially semicircular concave portion 65 from the upper surface side.

  As shown in FIG. 2, a part of the outer ring portion 62 of the upper leaf spring 60 </ b> U is assembled while being sandwiched between the connecting portion 34 of the yoke 30 and the cover 80. The cover 80 includes a substantially rectangular upper plate portion 81 having an opening 80a, and a plurality of column portions 82 provided at the corners of the upper plate portion 81 at right angles to the upper plate portion 81 and downward. Have

  A part of the outer ring portion 62 of the lower leaf spring 60L is assembled while being sandwiched between the end surface of the outer cylindrical portion 32 of the yoke 30 and the base 85. The base 85 includes a substantially rectangular bottom plate portion 86 having an opening 85 a and a plurality of column portions 87 provided at the corners of the bottom plate portion 86 at right angles to the bottom plate portion 86 and upward.

  The column portion 82 of the cover 80 and the column portion 87 of the base 85 are fitted to each other at corresponding positions. Thereby, at the time of assembly, the cover 80 and the base 85 can be bonded in a state where they are easily positioned.

  As shown in FIG. 14, three substantially triangular convex portions 201 are provided on the inner edge of the opening 80 a of the cover 80. The three substantially triangular convex portions 201 are arranged so as to be fitted to the three substantially triangular concave portions 72 provided on the outer edge of the stopper 70 with a gap. Thereby, the rotation of the holder 10 bonded to the stopper 70 in the circumferential direction can be restricted. Accordingly, during assembly, the lens assembly 100 can be easily attached to the holder 10 without causing problems such as plastic deformation of the connecting portion 63 of the leaf spring 60, peeling of the adhesion surface between the members, and breakage of the drawing portion 21 of the coil 20. Can be screwed together.

  In addition, a protruding portion 202 that protrudes inward in the radial direction from the opening 80 a is provided above the outer edge of the stopper 70. For example, when a large force is applied to the holder 10 due to an impact such as a drop, the protrusion 202 abuts against the stopper 70 to limit the displacement of the holder 10. Thereby, the plastic deformation of the connection part 63 of the leaf | plate spring 60 which supports the holder 10, peeling of the adhesion surface between members, the fracture | rupture of the drawer | drawing-out part 21 of the coil 20, etc. can be prevented.

  As shown in FIG. 2, the bottom plate portion 86 of the base 85 is provided with an insertion hole 88 through which the extension portion 92 of the sheet-like electrode 90 is inserted during assembly.

  Further, as shown in FIG. 2, three projections 89 are provided at an equal interval in the circumferential direction of the opening 85a and are integrally provided with the bottom plate portion 86 of the base 85 (see FIG. 3). In the assembled state, for example, the tip abuts against the lower surface of the flange portion 12 of the holder 10. The height of the protrusion 89 is longer than the distance from the upper surface of the bottom plate portion 86 of the base 85 to the lower leaf spring 60L. Therefore, the holder 10 is displaced upward. As a result, downward elastic force acts on the leaf springs 60U and 60L supporting the holder 10, and the back tension is always applied to the holder 10.

  Further, as shown in FIG. 2, the bottom plate portion 86 of the base 85 is provided with three circular holes 86a at substantially equal intervals in the circumferential direction of the opening 85a. The state of the soldering portion 22 on the sheet-like electrode 90 can be inspected from the outside of the base 85 through the circular hole 86a.

The assembly procedure of the above autofocus actuator will be described below.
[1] The coil 20 is fixed to the step 12a on the upper surface of the flange portion 12 of the holder 10 with an adhesive.
[2] Next, the four permanent magnets 40 are positioned at predetermined positions on the magnet mounting surface 33 on the inner peripheral surface of the outer cylindrical portion 32 of the yoke 30, and then fixed with an adhesive. In this state, the magnetic member 50 is attracted to the lower end surfaces of these permanent magnets 40 and fixed with an adhesive.
[3] Next, the holder 10 to which the coil 20 is fixed and the yoke 30 to which the above magnetic member 50 is attached are assembled. At this time, the cylindrical portion 11 of the holder 10 is inserted into the insertion hole 35 of the inner cylindrical portion 31 of the yoke 30. Further, the holder 10 and the yoke 30 are arranged so that the coil 20 is accommodated in a space between the outer peripheral surface of the inner cylindrical portion 31 of the yoke 30 and the permanent magnet 40.
[4] In the state [3], the upper and lower step portions 15 and 16 of the holder 10 are fitted with the inner ring portions 61 of the upper leaf spring 60U and the lower leaf spring 60L, respectively, and fixed with an adhesive.
[5] The stopper 70 is fixed to the upper surface of the upper leaf spring 60U bonded in [4] with an adhesive while the inner ring portion 61 of the upper leaf spring 60U is sandwiched between the upper surface of the cylindrical portion 11 and the upper surface. .
[6] The ring-shaped portion 91 of the sheet-like electrode 90 is bonded to the outer ring portion 62 of the lower leaf spring 60L bonded in [4] via an adhesive layer.
[7] The lead portion 21 and the dummy wire 23 of the coil 20 are wound around the protrusion 13 of the holder 10. Next, the leading ends of the lead portion 21 and the dummy wire 23 are soldered to the terminal portion 93 and the dummy terminal portion 95 of the sheet-like electrode bonded in [6]. Further, a stress relaxation agent 24 is applied to the portion wound around the protrusion 13 and the soldering portion 22.
[8] The cover 80 and the base 85 are attached to the parts assembled up to [7] so that the outer ring portion 62 of the upper leaf spring 60U and the lower leaf spring 60L is sandwiched between the yoke 30 and the upper leaf spring 60U. Next, the outer ring portion 62 of the upper leaf spring 60 </ b> U is bonded to the yoke 30 and the cover 80 between the yoke 30 and the cover 80. Further, the outer ring portion 62 of the lower leaf spring 60 </ b> L is bonded to the lower end surface of the outer cylindrical portion 32 of the yoke 30 and the base 85 between the lower end surface of the outer cylindrical portion 32 of the yoke 30 and the base 85. At this time, the extending portion 92 of the sheet electrode 90 is extended to the outside through the insertion hole 88 of the base 85.
[9] The lens assembly 100 is screwed into the holder 10 which is a part of the parts assembled up to [8].

Hereinafter, the operation of the autofocus actuator 1 will be described.
In FIG. 3, the direction of the magnetic field is from the permanent magnet 40 to the inner cylindrical portion 31 of the yoke 30. When a current flows counterclockwise when the coil 20 is viewed from above with the holder 10 in the initial position, an upward electromagnetic force is generated in the coil 20, that is, the holder 10. The holder 10 is displaced until the electromagnetic force and the elastic force of the leaf spring 60 that changes according to the displacement of the holder 10 are balanced. Since the electromagnetic force is controlled by the amount of current supplied to the coil 20, the holder 10, that is, the lens assembly 100 can be displaced to an arbitrary position by adjusting the amount of current supplied. In the autofocus actuator 1, the position information of the lens assembly 100 obtained from the supply amount of the current flowing through the coil 20 and an image detected by a detection element (not shown) positioned below the autofocus actuator 1. Information. The position information and the image information are calculated at high speed by a calculation unit having a predetermined autofocus algorithm, thereby specifying the autofocus position of the lens assembly 100. By controlling the current supply to the coil 20 based on the result, the autofocus actuator 1 can realize autofocus.

  In the autofocus actuator 1 described with reference to FIGS. 1 to 14, the yoke 30, the permanent magnet 40, and the magnetic member 50 can be improved as shown in FIGS. Hereinafter, an improved example of this yoke will be described with reference to FIGS.

  In the autofocus actuator 1 shown in FIGS. 1 to 14 described above, the yoke 30 has a cylindrical shape. Accordingly, the permanent magnet 40 also has a shape curved in an arc shape corresponding to the shape of the yoke 30. However, such a permanent magnet 40 is expensive and requires a special jig for positioning these magnets with respect to the yoke 30, resulting in a complicated manufacturing process.

  As an improved example of a rectangular parallelepiped, that is, a flat permanent magnet that can be used and in which the permanent magnet can be easily positioned and assembled, as shown in FIG. 15, the outer cylindrical portion 302 has a substantially square cross section. There are 300.

  As shown in FIG. 15, four magnet attachment surfaces 303 are provided on the inner peripheral surface of the outer cylindrical portion 302. In this yoke 300, four substantially flat permanent magnets 41 that can be easily manufactured can be attached while being attracted to the magnet attachment surface 303.

  Further, as shown in FIG. 15, concave portions 304 that are recessed inward are formed at the four corners of the outer cylindrical portion 302. The distance between the inner surfaces of two adjacent recessed portions 304 on both sides of one magnet mounting surface 303 is substantially equal to the width of the substantially flat permanent magnet 41. Therefore, the inner surface of the recessed portion 304 can be easily positioned by contacting the side surface of the substantially flat permanent magnet 41.

  The substantially flat permanent magnet 41 is magnetized so that, for example, the back surface in contact with the magnet mounting surface 303 is an S pole and the surface facing the back surface is an N pole. These substantially flat permanent magnets 41 are attached to a substantially square yoke 300. Thereby, the outer peripheral surface of the inner cylinder part 301 becomes a south pole, and the magnetic field which goes to the inner cylinder part 301 from the substantially flat permanent magnet 41 is formed.

  Furthermore, in this improved example, the inner cylinder portion 301 of the substantially square yoke 300 is also formed to have a substantially square cross section. A coil accommodated at a predetermined interval from the inner cylindrical portion 301 and the substantially flat permanent magnet 41 is also used which is wound in a substantially square shape. Thereby, since the direction of the current flowing through the coil and the direction of the magnetic field formed inside the substantially square-shaped yoke 300 are substantially perpendicular, a sufficient driving force can be obtained. In this improved example, the coil is not limited to the coil wound in the substantially square shape as described above. For example, a coil having another cross-sectional shape that allows a driving force to be obtained in the optical axis direction when the coil is housed and displaced in a space of a predetermined interval in the yoke 300 and the coil does not contact other members may be used. .

  When such a substantially square-shaped yoke 300 is used, as shown in FIG. 17, each of the outer edges of the four corners has a substantially rectangular ring shape in which concave portions that are recessed inward are formed. A magnetic member 51 is used. The width of the portion other than the recessed portion is equal to the thickness of the substantially flat permanent magnet 41.

  Further, as another modified example of the yoke that can use flat permanent magnets and that can be easily positioned and assembled, as shown in FIG. 16, the outer cylindrical portion 312 has a substantially hexagonal cross section. There is a yoke 310.

  In this improved example, as shown in FIG. 16, six magnet mounting surfaces 313 are provided on the outer cylindrical portion 312 of the yoke 310. In the yoke 310, the substantially flat permanent magnets 42 that can be easily manufactured can be attached while being attracted to the magnet attachment surface 313.

  Further, as shown in FIG. 16, in the yoke 310, a magnet mounting surface 313 is provided so that a part of the adjacent substantially flat permanent magnets 42 are in contact with each other. Thereby, the six substantially flat permanent magnets 42 attached to the magnet attachment surface 313 can be easily positioned.

  The substantially flat permanent magnet 42 is magnetized so that, for example, the back surface in contact with the magnet mounting surface 313 is an S pole and the surface facing the back surface is an N pole. These permanent magnets 42 are attached to a substantially hexagonal yoke 310. Thereby, the outer peripheral surface of the inner cylinder part 311 becomes a south pole, and the magnetic field which goes to the inner cylinder part 311 from the permanent magnet 42 is formed.

  Further, in this improved example, the inner cylindrical portion 311 of the substantially hexagonal yoke 310 is formed in a substantially circular cross section. Therefore, the coil accommodated at a predetermined interval from the inner cylindrical portion 311 and the substantially flat permanent magnet 42 can also be used that is wound in a substantially circular shape. Further, since the permanent magnet 42 is attached in a substantially hexagonal shape that is nearly circular, a sufficient driving force can be obtained even if a substantially circular coil is used.

  When such a substantially hexagonal yoke 310 is used, a hexagonal ring-shaped magnetic member is used as the magnetic member described above. The width of the hexagonal ring-shaped magnetic member is equal to the thickness of each permanent magnet 42.

  Hereinafter, a preferred embodiment of a yoke of an autofocus actuator according to the present invention will be described in detail. The present invention is an improvement of the outer cylindrical portion of the yoke of the autofocus actuator 1 described in FIGS. 1 to 14 described above, and the configuration of the actuator described above is applied to other configurations. Please note that. Therefore, description will be made with the aid of the constituent members of the autofocus actuator 1 described in FIGS. 1 to 14 as necessary.

  In the cylindrical yoke 30 as shown in FIG. 4 described above, as shown in FIG. 18, the thin plate is processed into a predetermined shape by bending drawing, and then the cut-off portion 38 (the wavy line portion) is pressed by a die. It is formed through a process of cutting and removing. Therefore, as shown by the solid line in FIG. 18, the cross section of the end surface 32a of the outer cylinder part 32 of the yoke 30 is a curved surface, and the contact between the end surface 32a of the outer cylinder part 32 and the outer ring part 62 of the lower leaf spring 60L. The area to do is small. Therefore, since sufficient adhesive strength cannot be obtained, the leaf spring 60 may be detached or displaced when an impact or the like is applied to the autofocus actuator 1.

  In order to eliminate such a fear, the present inventor has provided a yoke that has a large adhesion surface with the leaf spring 60, can secure a sufficient adhesion strength, and can be easily positioned with respect to the support frame (the cover 80 and the base 85). Devised. As a preferred embodiment of such a yoke, there is a yoke 320 with an adhesive surface having an adhesive surface with the outer ring portion 62 of the lower leaf spring 60L as shown in FIG.

  As shown in FIG. 19, the yoke 320 with an adhesive surface includes an inner cylindrical portion 321 having an insertion hole 323 through which the cylindrical portion 11 of the holder 10 is inserted, and an outer side of the inner cylindrical portion 321, as with the yoke 30 described above. And an outer cylinder part 322 provided at a predetermined interval, and an inner cylinder part 321 and a connecting part 324 in which the end of the outer cylinder part 322 opposite to the flange part 12 of the holder 10 is integrally connected. In addition, the yoke 320 accommodates the coil 20 in a space having a predetermined interval between the inner cylinder portion 321 and the outer cylinder portion 322.

  On the end surface 322a of the outer cylindrical portion 322 of the yoke 320 opposite to the connecting portion 324, an increased adhesive surface for adhering and holding the outer ring portion 62 of the leaf spring (lower leaf spring 60L) is integrally formed. Is provided. The increased adhesion surface is composed of a tab-shaped portion 325 formed integrally with the end surface 322a of the outer cylinder portion 322 so as to form a continuous surface with the end surface 322a and extend outside the outer cylinder portion 322. .

  As shown in FIG. 20, the yoke 320 cuts and removes the cut removing portion 328 (the wavy line portion) by press working after bending drawing like the yoke 30. As described above, the tab-shaped portion 325 can be formed integrally with the outer cylindrical portion 322 of the yoke 320, so that the yoke 320 can be easily manufactured.

  The tab-shaped portion 325 has a cross section as shown by a solid line in FIG. Therefore, the improved yoke 320 can secure a sufficient bonding surface for bonding to the lower leaf spring 60L.

  Four tab-like portions 325 are provided on the end surface of the outer cylindrical portion 322 of the yoke 320 at intervals of approximately 90 degrees along the outer periphery thereof.

  A surface of the lower plate spring 60L of the tab-shaped portion 325 that is in contact with the outer ring portion 62 is substantially parallel to the upper surface of the connecting portion 324 of the yoke 320. Further, four pieces are provided around the end surface 322a of the outer cylindrical portion 322 at intervals of approximately 90 degrees. As a result, the lower leaf spring 60L comes into contact with a larger area than the lower end surface of the outer cylindrical portion 32 from the cylindrical yoke 30 described above. Therefore, the yoke 320 can adhere and hold the outer ring portion 62 of the lower leaf spring 60L stably and reliably. As a result, the adhesive strength between the yoke 320 and the lower leaf spring 60L is increased, and it is possible to prevent the leaf spring from being detached or displaced when an impact or the like is applied to the autofocus actuator 1.

  The outer edge of each tab-shaped part 325 is substantially linear. Further, a contact point 326 with the circular arc formed by the outer cylindrical portion 322 is provided at the center in the width direction of the tab. The tangent line of the arc formed by the outer cylindrical portion 322 at the contact point 326 and the outer edge of the tab-shaped portion 325 substantially coincide with each other. Therefore, the width in the diameter direction of the cylindrical yoke 30 and the width connecting the contact points 326 of the tab-like portions 325 facing each other of the yoke 320 with the adhesive surface coincide with each other. Therefore, compared to the case where the cylindrical yoke 30 is used, the adhesion area between the outer ring portion 62 of the lower leaf spring 60L and the yoke 320 is reduced without changing the outer dimension (that is, the maximum diameter) of the yoke 320. Can be increased.

  Further, the four tab-shaped portions 325 of the yoke 320 have such shapes and sizes that the concave portions 327 are positioned between the adjacent tab-shaped portions 325. In the recesses 327, the column portion 82 of the cover 80 or the column portion 87 of the base 85 is positioned in the recess 327 when assembled. Thereby, the yoke 320 can be positioned with respect to the cover 80 and the base 85.

  Further, as shown in FIG. 8, the outer edge of the outer ring portion 62 of the leaf spring 60 is processed so as to have the same shape as the outer edge of the tab-like portion 325. Thereby, the lower leaf spring 60 </ b> L can be positioned with respect to the yoke 320.

  As described above, according to the autofocus actuator 1 according to the preferred embodiment of the present invention, the outer ring portion 62 of the lower leaf spring 60L is bonded to the end surface 332a of the outer cylinder portion and the tab-shaped portion 325. Therefore, the leaf spring is bonded to the yoke 320 in a more stable and reliable manner as compared to the case where the actuator 1 which is the premise of the present invention is bonded only to the end surface 32a of the outer cylindrical portion 32 of the yoke 30. . Further, the tab 320 can be provided with the yoke 320 having the same maximum diameter as the yoke 30. Further, the yoke 320 can be easily manufactured by integral molding. Further, since the cover 80 and the column portions 82 and 87 of the base 85 are positioned in the recess 327, the lower leaf spring 60L and the yoke 320 can be positioned with respect to the cover 80 and the base 85 during assembly.

  FIG. 21 shows a yoke 330 with an adhesive surface according to another preferred embodiment of the present invention. This yoke 330 with an adhesive surface has a flange portion 335 formed so as to extend to the outside of the outer cylinder portion 332 in a state of forming a continuous surface with the end surface 332a over the outer periphery of the end surface 332a of the outer cylinder portion 332. ing.

  As shown in FIG. 21, the yoke 330 with an adhesive surface includes an inner cylindrical portion 331 having an insertion hole 333 through which the cylindrical portion 11 of the holder 10 is inserted, and an outer side of the inner cylindrical portion 331, similar to the yoke 30 described above. And an outer cylinder part 332 provided at a predetermined interval, and an inner cylinder part 331 and a connecting part 334 in which the end of the outer cylinder part 332 opposite to the flange part 12 of the holder 10 is integrally connected. The yoke 330 accommodates the coil 20 in a space having a predetermined interval between the inner cylinder portion 331 and the outer cylinder portion 332.

  An increased bonding surface for integrally holding the outer ring portion 62 of the leaf spring (60L) is integrally provided on the end surface 332a of the yoke 330 opposite to the connecting portion 334 of the outer cylindrical portion 332. The increased adhesion surface is composed of a flange portion 335 formed integrally with the end surface 332a of the outer cylinder portion 332 of the yoke so as to form a continuous surface with the end surface 332a and extend outward.

  As shown in FIG. 20, the yoke 330 is similar to the yoke 30 described above, and after the thin plate is processed into a predetermined shape including the flange portion 335 by bending drawing, the cut-off portion 338 (the wavy line portion) is formed by pressing. Cut and remove. Since the flange portion 335 can also be formed integrally with the outer tube portion 332 of the yoke 330, the yoke 330 can be easily manufactured.

  The cross section of the end surface 332a of the outer cylinder part 332 and the flange part 335 forms a continuous plane. Therefore, the improved yoke 330 according to the second embodiment can secure a sufficient bonding surface for bonding to the lower leaf spring 60L as described above with reference to FIG.

  A surface of the lower plate spring 60 </ b> L of the flange portion 335 that contacts the outer ring portion 62 is substantially parallel to the upper surface of the connecting portion 334 of the yoke 330. Furthermore, it is provided along the outer periphery of the end surface 332 a of the outer cylinder portion 332. As a result, the lower leaf spring 60L comes into contact with a larger area than the lower end surface of the outer cylindrical portion 32 from the cylindrical yoke 30 described above. Thereby, the yoke 330 can adhere and hold the outer ring portion 62 of the lower leaf spring 60L stably and reliably. As a result, the adhesive strength between the yoke 320 and the lower leaf spring 60L is increased, and it is possible to prevent the leaf spring from being detached or displaced when an impact or the like is applied to the autofocus actuator 1.

  Further, the yoke 330 is formed so that the diameter of the outer cylinder portion 332 is made slightly smaller and the outer dimensions including the flange portion 335 are the same as the outer dimensions of the cylindrical yoke 30. Thereby, the adhesion area with the outer ring part 62 of the lower leaf | plate spring 60L can be increased, without an external dimension changing.

  According to the autofocus actuator according to another preferred embodiment of the present invention, the outer ring portion 62 of the lower leaf spring 60L is bonded to the end surface 332a of the outer cylinder portion 332 and the flange portion 335. Therefore, the leaf spring is firmly and firmly bonded to the yoke 330 in a stable and reliable manner as compared with the case where it is bonded only to the end surface of the outer cylindrical portion 32 of the yoke 30 as in the actuator 1 which is the premise of the present invention described above. . Further, the yoke 330 can be easily manufactured by integral molding.

  The substantially square-shaped yoke 300 and the substantially hexagonal yoke 310 shown in FIGS. 15 and 16, respectively, can similarly be provided with an adhesive surface. That is, tab-shaped portions and flange portions integrally formed on the end surfaces of the respective outer cylindrical portions 302 and 312 so as to form a continuous surface with these end surfaces and extend outside the yoke 300 and the substantially hexagonal yoke 310. Can be provided. Thereby, the adhesion area with the outer ring part 62 of the lower leaf spring 60L can be increased.

  Finally, it goes without saying that the present invention is not limited to the above-described preferred embodiments, and various improvements and modifications can be made within the scope of the following claims.

It is a perspective view of the appearance of an autofocus actuator according to the proposal of the present inventor. FIG. 2 is an exploded perspective view of the autofocus actuator shown in FIG. 1. FIG. 2 is a schematic cross-sectional view of the autofocus actuator shown in FIG. 1. It is a perspective view which shows a cylindrical yoke. It is sectional drawing of a yoke, Comprising: The mode of a magnetic field at the time of attaching only a permanent magnet is shown. It is sectional drawing of a yoke, Comprising: The mode of the magnetic field at the time of attaching a permanent magnet and a magnetic member is shown. It is a perspective view which shows a circular ring-shaped magnetic member. It is a top view of a leaf | plate spring. It is a top view of a sheet-like electrode. It is a part of schematic sectional drawing of the actuator for autofocus, Comprising: The state which connected the drawer | drawing-out part of the coil to the sheet-like electrode is shown. It is the elements on larger scale of A in FIG. It is a top view which shows the positional relationship of the flange part of a holder, the drawer part of a coil, and a sheet-like electrode. It is a top view of a stopper. It is a top view which shows the positional relationship of the opening part of a cover, and a stopper. It is a perspective view of a substantially square yoke and shows a state in which a substantially flat permanent magnet is attached. It is a perspective view of a substantially hexagonal yoke, and shows a state where a substantially flat permanent magnet is attached. It is a perspective view which shows a substantially square ring-shaped magnetic member. It is sectional drawing of the end surface of the outer cylinder part of the yoke shown in FIG. 1 is a perspective view of a tabbed yoke according to a preferred embodiment of the present invention. It is sectional drawing of the end surface of the outer cylinder part of a yoke shown in FIG.19 and FIG.21, and a tab-shaped part. FIG. 6 is a perspective view of a tabbed yoke according to another preferred embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Autofocus actuator 10 Holder 11 Cylindrical part 12 Flange part 12a Step part 13 Projection 14 Concave part 15 Convex part (Step part)
16 Step part 20 Coil 21 Lead part 22 Solder part 23 Dummy wire 24 Stress relaxation agent 30 Yoke 31 Inner cylinder part 32 Outer cylinder part 32a End surface 33 Magnet attachment surface 34 Connection part 35 Insertion hole 38 Cutting removal part 40-42 Permanent magnet 50, 51 Magnetic member 60 Leaf spring 60U Upper leaf spring 60L Lower leaf spring 61 Inner ring portion 62 Outer ring portion 63 Connection portion 65 Recess 66 Recess 70 Stopper 71 Opening 72 Recess 80 Cover 80a Opening portion 81 Upper plate portion 82 Column portion 85 Base 85a Opening 86 Bottom plate 86a Circular hole 87 Column 88 Insertion hole 89 Projection 90 Sheet electrode 91 Ring-shaped part 92 Extension part 93 Terminal part 94 Cover film 95 Dummy terminal part 100 Lens assembly 201 Convex part 202 Projection part 300 Yoke 301 Inner cylinder part 302 Outer cylinder part 303 Magnet mounting surface 304 Recessed part 310 Yoke 3 DESCRIPTION OF SYMBOLS 1 Inner cylinder part 312 Outer cylinder part 313 Magnet attachment surface 320 Yoke 321 Inner cylinder part 322 Outer cylinder part 322a End surface 323 Insertion hole 324 Connection part 325 Tab-shaped part 326 Contact point 327 Recessed part 328 Cutting removal part 330 York 331 Inner cylinder part 332 Outside Cylindrical part 332a End surface 333 Insertion hole 334 Connection part 335 Flange part 338 Cutting removal part

Claims (7)

A holder having a cylindrical part to which a lens is attached at one end;
A coil fixed to the holder so as to be located around the cylindrical portion of the holder;
A pair of leaf springs provided on both sides in the optical axis direction of the cylindrical portion of the holder, and supported so as to be displaceable in the optical axis direction with the holder positioned in a radial direction;
A permanent magnet provided so as to face the coil; and by energizing the coil, a lens attached to the holder is optically coupled to the optical axis by the interaction between the magnetic field generated in the coil and the magnetic field of the permanent magnet. In an autofocus actuator provided with a yoke for enabling position adjustment in a direction,
The yoke has an end surface with which a leaf spring located on the other end side of the cylindrical portion of the holder abuts, and an adhesive surface for adhering and holding the leaf spring is integrally formed on the end surface. An autofocus actuator characterized by   The yoke has an inner cylinder part forming an insertion hole through which the cylindrical part of the holder is inserted, and an outer cylinder part provided outside the inner cylinder part at a predetermined interval via a connecting part. 2. The autofocus actuator according to claim 1, wherein an end surface of the yoke is an end surface of the outer cylinder portion.   The bonding surface is composed of at least one tab-like portion formed integrally with the end surface of the outer tube portion of the yoke so as to form a continuous surface with the end surface and to extend outside the outer tube portion. The autofocus actuator according to claim 2.   4. The autofocus actuator according to claim 3, wherein four tab-shaped portions are provided at an interval of approximately 90 degrees on an end surface of the outer cylinder portion of the yoke. 5.   5. The autofocus actuator according to claim 4, wherein each of the tab-shaped portions has an outer edge that substantially coincides with a tangent to an end surface of the outer cylindrical portion of the yoke.   6. The autofocus actuator according to claim 5, wherein the tab-shaped portion is formed to have a concave portion between adjacent tab-shaped portions. The bonding surface includes a flange portion formed integrally with the end surface of the outer cylinder portion of the yoke so as to form a continuous surface with the end surface and to extend to the outside of the outer cylinder portion. The autofocus actuator according to claim 2.

Images