WO2018235463A1 - Lens drive device, camera module using said lens drive device, and method for manufacturing lens drive device - Google Patents

Abstract

[Problem] Provided are: a lens drive device wherein the elastic force of an upper sheet spring and a lower sheet spring can be set appropriately, the upper and lower sheet springs supporting a lens holding member; a camera module using the lens drive device; and a method for manufacturing the lens drive device. [Solution] A lens holding member 10 on which a coil 60 is mounted is supported by an upper sheet spring 30 and a lower sheet spring 20A, 20B, and in an initial state in which the coil 60 is not electrically energized, the lens holding member 10 is in contact with a support base 40. The upper affixed-side support section of the upper sheet spring 30 is affixed to a support member 50 disposed inside the ceiling section of a case 3. A biasing force for biasing the lens holding member 10 toward the support base 40 is smaller on the lower sheet spring 20A, 20B side than on the upper sheet spring 30 side.

Description

Lens driving device, camera module using the lens driving device, and method of manufacturing lens driving device

The present invention relates to a lens driving device in which a lens holding member and a plate spring for supporting the lens holding member are housed in a case, a camera module using the lens driving device, and a method of manufacturing the lens driving device.

Patent Document 1 describes an invention related to a lens drive device.
This lens drive device is provided with a base member, a yoke covering the base member, and an upper plate spring and a lower plate spring. A spacer member is fixed to the inside of the top surface of the yoke, and the upper leaf spring is attached between the lower surface of the spacer member and the upper portion of the lens holding member. The lower leaf spring is attached between the surface of the base member and the lower portion of the lens holding member.

A lens holding member having a coil is accommodated in the inside of the yoke, and the lens holding member is supported movably in the optical axis direction of the lens by an upper plate spring and a lower plate spring. A magnet is fixed inside the yoke, and the magnet faces the outside of the coil.

As described in paragraph “0042” of Patent Document 1, in the lens drive device, the lens holding member is biased toward the base member by the lower plate spring when the coil is not energized. The lens holding member is in contact with the buffer portion protruding from the upper surface of the base member. When a drive current is supplied to the coil through the pair of lower leaf springs, the lens holding member can be elastically deformed by the drive current flowing through the coil and the magnetic field from the magnet facing the coil. It is operated in the direction. This action brings the image into focus on the imaging device.

Utility model registration 3182065 gazette

In the lens driving device described in Patent Document 1, the spacer member is fixed to the inside of the top surface of the yoke, and the fixed side support portion which is the outer portion of the upper plate spring is fixed to the lower surface of the spacer member. A movable support, which is an inner portion of the spring, is fixed to the top of the lens holding member.

In order to miniaturize and thin the lens drive device of this type, it is required to reduce the height of the yoke in the optical axis direction. Since there is a limit in reducing the thickness dimension of the spacer member in the optical axis direction, when the yoke is thinned, the lower surface of the spacer member approaches the base member inside the yoke. As a result, in the upper side plate spring, the height difference between the fixed side support portion fixed to the lower surface of the spacer member and the movable side support portion fixed to the upper portion of the lens holding member becomes large, and the elastic deformation portion is bent As the amount increases, the biasing force for biasing the lens holding member toward the base member by the upper plate spring becomes excessive. As a result, the sum of the biasing forces of the upper and lower plate springs is increased, and the load when driving the lens holding member in the optical axis direction by the magnetic drive circuit configured by the coil and the magnet is increased. Electricity will also deteriorate.

The present invention solves the above-mentioned conventional problems, and a lens drive device capable of appropriately setting an elastic force by an upper plate spring and a lower plate spring supporting a lens holding member, and using the lens drive device It is an object of the present invention to provide a method of manufacturing a camera module and a lens driving device.

The present invention comprises a support base, a case covering the support base, a lens holding member at least a part of which can be mounted on the inside of the case and on which the lens body can be mounted, and the lens holding member Upper and lower leaf springs movably supported in the optical axis direction, a coil mounted on the lens holding member, a magnet provided inside the case and facing the coil, and a ceiling portion of the case A support member fixed to the inside of the
A lower fixed support and a lower movable support, and a lower elastic arm connecting the lower fixed support and the lower movable support are integrally formed on the lower leaf spring, the lower The fixed side support portion is fixed to the support base side, and the lower movable side support portion is fixed to the lower portion of the lens holding member,
In the upper leaf spring, an upper fixed side support portion and an upper movable side support portion, and an upper elastic arm portion connecting the upper fixed side support portion and the upper movable side support portion are integrally formed. The fixed side support portion is fixed to the lower portion of the support member, and the upper movable side support portion is fixed to the upper portion of the lens holding member,
In the lens driving device in which the lens holding member is in contact with the support base directly or through another member in an initial state in which the coil is not energized.
The upper movable side support portion of the upper leaf spring is positioned at an upper position away from the support base than the upper fixed side support portion, and the upper elastic arm portion is bent.
In the initial state, the lower elastic arm portion directs the lens holding member toward the support base than a biasing force in which the upper elastic arm portion biases the lens holding member toward the support base. It is characterized in that the biasing force is smaller.

In the lens driving device according to the present invention, a spring constant of the lower elastic arm is smaller than a spring constant of the upper elastic arm.
For example, the cross-sectional area of the lower elastic arm is smaller than the cross-sectional area of the upper elastic arm.

In the lens driving device according to the present invention, the support member has a frame shape, and the upper portion of the lens holding member is located inside the frame shape and located above the lower portion of the support member. It can be configured.

In the lens driving device according to the present invention, in the initial state, preferably, the lower fixed side supporting portion and the lower movable side supporting portion of the lower leaf spring are located on the same plane perpendicular to the optical axis. .

In the lens driving device according to the present invention, a stopper projection is formed on one of the lower portion of the lens holding member and the support base to bring the lower portion of the lens holding member into contact with the support base in the initial state. It is preferable that at least a part of the stopper projections be located between the lower fixed support and the lower movable support.

In the lens driving device of the present invention, spring fixing surfaces are formed at a plurality of locations on the upper surface of the support base,
A pair of lower leaf springs is provided, and the lower fixed side supporting portions of the lower leaf springs are supported on the spring fixing surface,
A conductive plate may be stacked on the lower fixed side support portion of each lower leaf spring, and a connection terminal may be formed on the conductive plate.
For example, the lower fixed side support portion and the conductive plate are welded, and the lower fixed side support portion of the lower leaf spring is bonded to the support base.

The camera module according to the present invention is characterized by having a lens body held by the lens holding member of the lens driving device, and an image pickup device facing the lens body.

Next, according to the present invention, a support base, a case covering the support base, a lens holding member at least a part of which can be mounted on the inside of the case and capable of mounting a lens body, and the lens holding member Upper and lower leaf springs movably supported in the optical axis direction of the lens body, a coil mounted on the lens holding member, a magnet provided inside the case and facing the coil, and the case A support member fixed to the inside of the ceiling of the
A lower fixed support and a lower movable support, and a lower elastic arm connecting the lower fixed support and the lower movable support are integrally formed on the lower leaf spring. The lower fixed side support portion is fixed to the support base side, and the lower movable side support portion is fixed to the lower portion of the lens holding member,
In the upper leaf spring, an upper fixed side support portion and an upper movable side support portion, and an upper elastic arm portion connecting the upper fixed side support portion and the upper movable side support portion are integrally formed, The upper fixed side support portion is fixed to the lower portion of the support member, and the upper movable side support portion is fixed to the upper portion of the lens holding member,
In a method of manufacturing a lens driving device in which the lens holding member is in contact with the support base directly or through another member in an initial state in which the coil is not energized.
(A) positioning the upper movable side support portion of the upper plate spring above the support base with respect to the upper fixed side support portion to cause deflection in the upper elastic arm portion;
(B) fixing the upper movable side support portion and the upper portion of the lens holding member;
Have
In the initial state, the lower elastic arm portion directs the lens holding member toward the support base than a biasing force in which the upper elastic arm portion biases the lens holding member toward the support base. It is characterized in that the biasing force to be biased is set smaller.

In the method of manufacturing the lens driving device, before the step (a),
Bonding and fixing the support member and the upper fixed side support portion of the upper leaf spring inside the ceiling portion of the case;
Bonding and fixing the magnet to the inner surface of the case;
Attaching the lower leaf spring and the lens holding member having the coil on the support base to produce an assembly;
Have
In the step (a), by combining the assembly and the case such that the assembly is inserted into the case, the upper portion of the lens holding member and the upper movable portion of the upper leaf spring are movable. The side support portion is made to abut to cause the upper elastic arm portion to bend.

In the lens drive device manufacturing method of the present invention, the support member has a frame shape, and the upper portion of the lens holding member can be positioned above the lower portion of the support member inside the frame shape.

In the method of manufacturing a lens drive device according to the present invention, the support member, an adhesive for fixing the upper fixed side support portion of the upper leaf spring, and the magnet on the inner surface of the case It is preferable to cure the adhesive for fixing in the same heating step.

In the method of manufacturing a lens drive device according to the present invention, a spring constant of the lower elastic arm is smaller than a spring constant of the upper elastic arm.
For example, the cross-sectional area of the lower elastic arm is formed smaller than the cross-sectional area of the upper elastic arm.

In the method of manufacturing a lens driving device according to the present invention, in the initial state, the lower fixed side supporting portion and the lower movable side supporting portion of the lower leaf spring are located on the same plane perpendicular to the optical axis. Is preferred.

In the method of manufacturing a lens drive device according to the present invention, a stopper projection which brings the lower portion of the lens holding member into contact with the support base in the initial state to either the lower portion of the lens holding member or the support base. It is preferable that at least a part of the stopper projections be located between the lower fixed side support portion and the lower movable side support portion.

In the method of manufacturing a lens driving device according to the present invention, before the step (a),
(C) using the pair of conductive plates having connection terminals and the pair of lower leaf springs, and stacking the lower fixed side supporting portion of each lower leaf spring and the conductive plate;
(D) welding the lower fixed side supporting portion and the conductive plate respectively stacked in the step (c);
(E) The lower fixed side welded in the step (d) on the support base so that the lower fixed side support portion is disposed between the support base and the conductive plate Arranging and fixing a support portion and the conductive plate, respectively;
It is preferable to have

In the method of manufacturing a lens drive device according to the present invention, the plate thickness of the conductive plate is larger than the plate thickness of the lower leaf spring,
In the step (d), the lower fixed side support portion and the conductive plate are irradiated with a laser from the lower fixed side support portion to the overlapping portion of the lower fixed side support portion and the conductive plate. It is preferable to weld

According to the present invention, in the structure in which the support member is fixed to the inside of the ceiling of the case and the upper fixed support of the upper leaf spring is fixed to the lower portion of the support member, the upper leaf spring faces the lens holding member to the support base. The biasing force by which the lower leaf spring biases the lens holding member toward the support base is smaller than the biasing force by which the lens holding member is biased. Therefore, even if the upper fixed side support portion and the upper movable side support portion of the upper plate spring are provided with a difference in height to increase the biasing force of the upper elastic arm, the lens holding member is attached by the upper plate spring and the lower plate spring. The sum of biasing forces can be reduced, and the load when driving the lens driving member in the optical axis direction can be reduced. Further, in the case where the support member has a frame shape and the upper portion of the lens holding member is made to intervene inside the frame shape, the case can be thinned.

In particular, by making the spring constant of the lower elastic arm portion smaller than the spring constant of the upper elastic arm portion, it is possible to appropriately set the total sum of biasing forces for biasing the lens holding member with the upper leaf spring and the lower leaf spring. .

A perspective view showing an appearance of a lens drive device according to an embodiment of the present invention; An exploded perspective view showing components of the lens driving device shown in FIG. 1; An exploded perspective view showing an assembly of a support base, a lower leaf spring and a lens holding member provided at the lower part of the lens driving device shown in FIG. 1; Fig. 3 is a bottom view of the assembled assembly of the components shown in Fig. 3 from below with the support base removed. 1 is a sectional view of the lens driving device shown in FIG. 6 is a cross-sectional view of the lens driving device taken along the line VI-VI in FIG. 6 is a sectional view in which the lens holding member and the magnet are removed from the sectional view shown in FIG. An exploded perspective view showing a part of the support member, the upper leaf spring and the magnet, An exploded perspective view showing a lower leaf spring, a lens holding member and an upper leaf spring, An exploded perspective view showing a process of attaching the lower leaf spring and the conductive plate to the support base;

The overall structure of the lens drive device 1 according to the embodiment of the present invention is shown in FIGS. 1, 2 and 5, and FIG. 3 shows a support base located in the lower part, a lower leaf spring and a lens holding member. Assembly 70 is shown.

The lens driving device 1 has a lens holding member 10. The lens holding member 10 is formed by injection molding of a synthetic resin material. As shown in FIG. 3, the lens holding member 10 has a cylindrical portion 13. The cylindrical portion 13 is a relatively thin cylindrical body, and has a central hole 13a continuous in the Z1-Z2 direction. A lens body (a lens barrel or a lens barrel) is attached to the central hole 13 a of the cylindrical portion 13. The lens body is composed of a lens set in which one lens or a plurality of lenses is combined, and a lens holder holding the lens or the lens set. For example, a female screw is formed in the center hole 13a, a male screw is formed on the outer peripheral surface of the lens holder, and the male screw is screwed to the female screw, whereby the lens body is mounted inside the tubular portion 13. Will be installed. Alternatively, the lens body is inserted into the center hole 13a, and the lens body and the inner surface of the cylindrical portion 13 are fixed with an adhesive.

The Z1-Z2 direction shown in each drawing is a vertical direction, and is a direction (optical axis direction) parallel to the optical axis O of the lens body. The lens drive device 1 whose entire structure is shown in FIGS. 1, 2 and 5 is mounted on a portable electronic device such as a mobile phone. An imaging element such as a CCD is disposed on the Z2 side of the lens driving device 1. The lens drive device 1, the lens body and the imaging device are combined to constitute a camera module. In the camera module, when the lens holding member 10 and the lens mounted thereon are moved in the Z1-Z2 direction, automatic focusing of the image formed on the imaging device is performed.

As shown in FIGS. 1, 2 and 3, the lens driving device 1 is provided with a support base 40 and a case 3. The support base 40 and the case 3 are combined to constitute a housing having a storage space inside. In the storage space, a lens holding member 10 having a coil 60, an upper leaf spring 30 for supporting the upper portion of the lens holding member 10, and a support member 50 located between the ceiling portion 3a of the case 3 and the upper leaf spring 30. The lower leaf springs 20A and 20B for supporting the lower portion of the lens holding member 10, and four magnets M facing the coil 60 are provided.

As shown in FIGS. 1 and 2, the case 3 is formed of a magnetic steel plate (steel plate made of ordinary steel) or the like and functions as a magnetic yoke. The case 3 has a quadrangular shape (rectangular shape) in a plan view as viewed from the optical axis direction, and includes four side wall portions 3d and an angular surface wall portion 3e connecting the respective side wall portions 3d as outer wall portions. It is provided. The case 3 has a ceiling 3a, and an opening 3b is formed in the ceiling 3a. As shown in FIG. 3, an opening 44 is formed at the center of the support base 40, and the opening 44 of the support base 40 is opposed to the center hole 13a of the lens holding member 10 from below. The opening 3b of the ceiling 3a faces the central hole 13a from above. The planar shape of the opening 3b of the case 3 is a quadrilateral, and as shown in FIG. 2, from the four corners of the inner edge of the opening 3b, the opposing yokes 3c bent in the Z2 direction are integrated. Is formed. As shown in FIGS. 6 and 7, the opposing yokes 3c are opposed to the inner surface of each corner surface wall 3e from the inside of the case.

As shown in FIGS. 2 and 5, in the inside of the case 3, a support member (spring fixing member) 50 is provided on the inner side (inner side) which is the Z2 side of the ceiling portion 3 a. The support member 50 is formed of a nonmagnetic material such as a synthetic resin material. The support member 50 has a rectangular frame shape, and includes four side support portions 51 and corner support portions 52 located at four corners. The side support 51 faces the inner surface of the side wall 3 d of the case 3, and the corner support 52 faces the inner surface of the corner wall 3 e of the case 3. Case contact parts 53 are formed on each of the four corner support parts 52. The case contact portion 53 is formed to project in the Z1 direction more than the upper surface of the side support portion 51 of the support member 50.

As shown in FIGS. 5 and 8, a spring fixing surface 55 is provided on the lower surface of the side support portion 51 formed on the support member 50 in the Z2 direction. The spring fixing surface 55 is formed to project from the lower surface of the side support portion 51 toward the Z2 side, and the surface (lower surface) thereof is a flat surface parallel to the XY plane. The spring fixing surfaces 55 are provided at both ends of each side support portion 51.

As shown in FIG. 7 and FIG. 8, support ridges 56 are integrally formed on the four corner support portions 52 of the support member 50 so as to project downward (in the Z2 direction). There is. The support projection 56 has a trapezoidal shape in a plan view as viewed from the Z2 side. At two points on the downward facing surface of the support ridge 56, magnet abutments 57 are formed which project in the Z2 direction. The surface of the magnet contact portion 57 facing in the Z2 direction is a magnet contact surface parallel to the XY plane.

As shown in FIGS. 2, 5 and 7, the upper leaf spring 30 is fixed to the lower surface of the support member 50 facing in the Z2 direction. The upper leaf spring 30 has a rectangular frame-shaped upper fixed side support portion 31, a pair of upper movable side support portions 32 located on the inner side thereof on the Y1 side and the Y2 side, and the upper fixed side support portion 31. An upper elastic arm 33 connecting the upper movable side support 32 is integrally formed of a leaf spring metal material. The upper leaf spring 30 is formed by etching. The upper leaf spring 30 is arranged such that the thickness direction is the optical axis direction when the lens drive device 1 is assembled.

As shown in FIGS. 8 and 9, the upper fixed side support portion 31 of the upper leaf spring 30 is positioned at four corner portions and a belt-like side facing portion 31a linearly extending in the X and Y directions. The rectangular surface facing portion 31b is continuously and integrally formed. The side facing portion 31 a is a portion facing the inner surface of the side wall 3 d of the case 3, and the corner face facing portion 31 b is a portion facing the inner surface of the corner wall 3 e of the case 3. The side wall 3d of the case 3 is a flat portion of the side wall of the case 3, and the corner wall 3e is located between the adjacent side walls 3d and is the side of the case 3 Is the portion where the outer wall of the other is curved.

The two upper elastic arm portions 33 located on the Y1 side connect the side facing portion 31a formed on the Y1 side of the upper fixed side support portion 31 and the upper movable side support portion 32 located on the Y1 side. . The two upper elastic arm portions 33 located on the Y2 side connect the side facing portion 31a formed on the Y2 side of the upper fixed side support portion 31 and the upper movable side support portion 32 located on the Y2 side. .

As shown in FIGS. 7 and 8, the side facing portion 31 a of the upper fixed side support portion 31 of the upper leaf spring 30 is abutted against the spring fixing surface 55 formed on the side support portion 51 of the support member 50. At this time, a trapezoidal support protuberance 56 formed on the support member 50 is inserted between the angular surface facing portion 31 b of the upper leaf spring 30 and the upper elastic arm portion 33, and the support member 50 and the upper leaf spring 30. And are positioned relative to one another. Further, the support member 50 can be positioned in the direction of the optical axis O inside the case 3 by abutting the case contact portion 53 against the inner surface (the lower surface facing the Z2 side) of the ceiling portion 3a.

With the support member 50 and the upper fixed support 31 of the upper leaf spring 30 installed inside the ceiling 3 a of the case 3, the side facing part 31 a of the upper fixed support 31 and the corner facing part 31 b A flowable thermosetting adhesive is provided at the interface. The adhesive penetrates into the butting portion of the inner surface of the ceiling portion 3a of the case 3 and the case contact portion 53 of the support member 50 by capillary action, and the spring fixing surface 55 of the support member 50 and the upper leaf spring 30. It also penetrates into the joint with the side facing portion 31a.

As shown in FIGS. 2 and 6, the lens drive device 1 is provided with four magnets M. The four magnets M are formed independently of one another. Each magnet M has an outer surface Ma directed radially outward about the optical axis O and a magnetized surface Mg directed to the optical axis O. Bonding surfaces Mb that are inclined and opposed to each other are formed between the outer side surface Ma and the magnetized surface Mg. Each magnet M has a flat upper surface Mc facing in the Z1 direction. Each magnet M is magnetized such that the magnetized surface Mg and the outer surface Ma have different polarities. The magnetized surfaces Mg of all the magnets M are magnetized so as to have the same polarity.

As shown in FIGS. 5 and 6, the four magnets M are respectively disposed inside the corner wall 3 e inside the case 3. A thermosetting adhesive having fluidity is applied to the inner surfaces of the side wall portions 3d of the case 3 located on both sides of the corner wall portion 3e, and the adhesive surface Mb of the magnet M is opposed at an angle of 90 degrees. The inner surface of the side wall 3d is magnetically attracted. With the adhesive interposed between the magnet M and the case 3, each magnet M is moved in the Z1 direction, and the upper surface Mc facing in the Z1 direction is formed on the corner support 52 of the support member 50. The magnet contact portion 57 is abutted. As a result, each magnet M is positioned so as to be fixed at the same position in the direction of the optical axis O, with the magnetized surface Mg directed to the optical axis O.

With the support member 50, the upper leaf spring 30, and the magnet M incorporated in the case 3, the process proceeds to the heating process. In this heating step, the adhesive interposed between the inner surface of the ceiling 3a of the case 3 and the support member 50, the adhesive interposed between the spring fixing surface 55 and the side facing portion 31a, and the inner surface of the case 3 The adhesive between the magnet and the magnet M is simultaneously cured.

After the support member 50, the upper leaf spring 30, and the magnet M are incorporated in the case 3, the assembly 70 shown in FIG. 2 is assembled in the case 3. An exploded perspective view of the assembly 70 is shown in FIG.
The assembly 70 shown in FIG. 3 is provided with a pair of lower leaf springs 20A and 20B separated from each other between the support base 40 and the lens holding member 10 positioned thereon. The lower leaf spring located on the Y1 side is represented by a symbol 20A, and the lower leaf spring located on the Y2 side is represented by a symbol 20B. In each of the lower leaf springs 20A and 20B, the lower fixed side support portion 21, the lower movable side support portion 22, and the lower elastic arm portion 23 connecting the lower fixed side support portion 21 and the lower movable side support portion 22 are It is integrally formed of a conductive leaf spring metal material. For example, the lower leaf springs 20A and 20B are formed of a springy stainless steel plate, a phosphor bronze plate, or the like. The lower leaf springs 20A and 20B are formed by etching. The lower leaf springs 20A and 20B are arranged such that the thickness direction is the optical axis direction in a state where the lens drive device 1 is assembled.

As shown in FIG. 3, the lower fixed side support portion 21 of the lower leaf spring 20A located on the Y1 side is formed with an attachment portion 21a located on the X2 side and an attachment portion 21b located on the X1 side. The lower fixed side support portion 21 of the lower leaf spring 20B located on the Y2 side is also formed with an attachment portion 21a located on the X2 side and an attachment portion 21b located on the X1 side. In the lower leaf springs 20A and 20B, mounting holes 24a are formed in the mounting portions 21a positioned on the X2 side, and mounting holes 24b are formed in the mounting portions 21b positioned on the X1 side.

As shown in FIGS. 2 and 3, the conductive plate 25A is overlapped on the upper side (Z1 side) of the X2 side mounting portion 21a of the lower leaf spring 20A located on the Y1 side, and the lower leaf spring 20B located on the Y2 side. The conductive plate 25B is superimposed on the upper side (Z1 side) of the attachment portion 21a on the X2 side of the upper surface of the second conductive plate 25B. The conductive plates 25A and 25B are formed of a conductive metal plate, and are formed of, for example, a rolled steel plate whose surface is plated with gold, or a plate material of a brass other than copper alloy. The conductive plates 25A, 25B have a support plate portion 26 parallel to the XY plane, and a connection terminal 27 bent from the support plate portion 26 toward the Z2 side below. A hole 28 is formed in the support plate 26.

The mounting portion 21a and the support plate portion 26 are welded in a state where the mounting portion 21a of the lower leaf spring 20A and the support plate portion 26 of the conductive plate 25A are positioned and overlapped. This welding is performed by laser spot welding. The mounting portion 21a of the lower leaf spring 20B on the Y2 side and the support plate portion 26 of the conductive plate 25B are also welded in the same manner. The lower leaf springs 20A and 20B have a smaller thickness than the conductive plates 25A and 25B, and the laser spot welding is performed by irradiating the laser from the lower leaf springs 20A and 20B (Z2 side).

As shown in FIG. 3, the support base 40 has a rectangular planar shape, and is formed of a synthetic resin material that is a nonmagnetic material. Spring fixing surfaces 41A and 41B are formed on four corners of the support base 40. Two spring fixing surfaces located on the X2 side are indicated by a reference numeral 41A, and two spring fixing surfaces located on the X1 side are indicated by a reference 41B. Positioning projections 42a are integrally formed on two spring fixing surfaces 41A located on the X2 side, and positioning projections 42b are integrally formed on two spring fixing surfaces 41B located on the X1 side. The positioning protrusions 42a and 42b protrude in the Z1 direction. The positioning projections 42a and the positioning projections 42b are cylindrical bodies each having a constant radius.

As shown in FIG. 3, the through hole 43 is formed in the support base 40 at a position adjacent to the spring fixing surface 41A formed on the X2 side. The through holes 43 are formed between the side 40c facing the X2 side of the support base 40 and the respective spring fixing surfaces 41A. The through hole 43 is formed by penetrating the support base 40 in the vertical direction (Z1-Z2 direction).

In a state in which the support plate portions 26 of the conductive plates 25A and 25B are overlapped and welded to the attachment portions 21a on the X2 side of the lower leaf springs 20A and 20B, the attachment holes 24a formed in the respective attachment portions 21a The positioning projections 42 a provided on the two spring fixing surfaces 41 A of the support base 40 are inserted through the holes 28 formed in the support plate 26. As a result, the respective attachment portions 21a and the support plate portion 26 are superimposed and positioned on the spring fixing surface 41A. Further, positioning projections 42b provided on two spring fixing surfaces 41B are inserted into the respective mounting holes 24b formed in the X1 side mounting portions 21b of the lower leaf springs 20A and 20B, and the respective mounting portions are formed. 21b is positioned and installed on the spring fixing surface 41B.

An adhesive is applied to the positioning projections 42a and 42b provided on the support base 40, and the mounting portions 21a of the support base 40 and the lower leaf springs 20A and 20B are formed by heat curing or UV curing of the adhesive. , 21b are adhesively fixed. Further, the attachment portions 21a of the lower leaf springs 20A and 20B and the conductive plates 25A and 25B are also adhered to each other. The tips of the four positioning projections 42a and 42b are heated and pressed to form caulking deformation portions at the tips of the positioning projections 42a and 42b, and the lower leaf springs 20A and 20B and the support base 40 are formed. The conductive plates 25A, 25B may be fixed by caulking.

When the conductive plates 25A and 25B are fixed on the support base 40, the connection terminals 27 integral with the conductive plates 25A and 25B are inserted into the through holes 43 formed in the support base 40, and the connection is made. The tip of the terminal 27 on the Z2 side is exposed below the lower surface of the support base 40. At this time, by filling the inside of the through hole 43 with an adhesive, the conductive plates 25A and 25B can be firmly fixed to the support base 40. Furthermore, the through hole 43 is closed with an adhesive and supported. It becomes easy to prevent that a liquid etc. infiltrate into the inside of case 3 from the lower side of base 40 through penetration hole 43.

As shown in FIG. 3, mounting holes 22a are respectively formed on the lower movable side support portions 22 of the lower leaf springs 20A and 20B on the X1 side and the X2 side. As shown in the bottom view of FIG. 4, on the lower surface of the lens holding member 10 directed in the Z2 direction, spring fixing surfaces 10 b are provided on the X1 side and the X2 side. In each spring fixing surface 10b, a protrusion 10c projecting in the Z2 direction is integrally formed on the Y1 side, and a protrusion 10d projecting in the Z2 direction is integrally formed on the Y2 side. Mounting holes 22a formed on both ends of the lower movable side support 22 of the lower leaf spring 20A on the Y1 side are fitted to the projections 10c, and the respective projections 10c are thermally crimped to lower the lower leaf spring 20A. The side support portion 22 is fixed to two spring fixing surfaces 10 b of the lower surface of the lens holding member 10. Similarly, the lower movable side support portion 22 of the lower leaf spring 20B is fixed by fitting the mounting holes 22a formed at both ends of the lower leaf spring 20B on the Y2 side to the respective projections 10d and thermally caulking. It is fixed to the spring fixing surface 10b of the location.

Since the support base 40 is injection molded of a synthetic resin material, the four spring fixing surfaces 41A and 41B maintain high mutual flatness. By fixing the lower fixed side support portions 21 of the lower leaf springs 20A and 20B by bringing the lower fixing side support portions 21 into contact with the spring fixing surfaces 41A and 41B and fixing them, the flatness of the lower leaf springs 20A and 20B can be maintained high and fixed. . Thereby, the inclination of the lens holding member 10 supported by the lower movable side support portion 22 of the lower leaf springs 20A, 20B can be suppressed, and the lens holding member 10 is arranged along the spring fixing surfaces 41A, 41B of the optical axis O. It can be installed in a state in which the degree of perpendicularity to the plane (XY plane) is maintained high. In the present embodiment, the four spring fixing surfaces 41A and 41B are projected upward (Z1 side) from the upper surface of the support base 40 and located on the same plane, but the spring fixing surfaces 41A , 41 B may not protrude from the upper surface of the support base 40.

As shown in FIG. 3, a flange portion 11 is formed on the Z2 side and a plurality of restricting protrusions 12 are formed on the Z1 side on the outer side of the cylindrical portion 13 of the lens holding member 10. The flange portion 11 may have a wedge shape extending substantially continuously in the circumferential direction around the optical axis O, or may be formed intermittently in the circumferential direction. The restricting protrusions 12 are formed at intervals in the circumferential direction. The flange portion 11 and the plurality of restricting protrusions 12 face each other in the optical axis direction (Z1-Z2 direction).

As shown in the bottom view of FIG. 4, protrusions 19 a and 19 b are integrally formed at two positions on the bottom surface of the lens holding member 10 facing in the Z2 direction. The protrusions 19a and 19b protrude in the Z2 direction. The protrusion 19a located on the Y1 side is a winding protrusion that fixes the winding start end 61a of the wire forming the coil 60, and the protrusion 19b located on the Y2 side is a winding protrusion that fixes the winding end 61b of the wire. The conducting wire for forming the coil 60 is a coated conducting wire and has a copper wire which is a conductive metal wire and an insulating covering layer which covers the copper wire. The covering layer has a two-layer structure of an insulating layer such as polyurethane resin for covering a copper wire and a fusion layer such as polyamide resin on the surface thereof.

The covering layer is removed at the winding start end 61a of the conducting wire, and the winding start end 61a is wound around the protrusion 19a on the Y1 side shown in FIG. The conducting wire extending from the protrusion 19 a is wound between the flange portion 11 and the restricting protrusion 12 on the outer side of the cylindrical portion 13 of the lens holding member 10. In the winding process, the conductive wire is heated by application of hot air or the like, and the insulating layers are fusion-bonded by the fusion of the fusion layers to form the coil 60. The winding end 61b of the conducting wire which has finished winding the coil 60 is pulled out to the lower surface of the lens holding member 10, the covering layer is removed, and is wound around the protrusion 19b on the Y2 side shown in FIG.

As shown in FIG. 4, when the lower movable side support portion 22 of the lower leaf springs 20A and 20B is fixed to the spring fixing surfaces 10b and 10b of the lower surface of the lens holding member 10, it is wound around the protrusion 19a on the Y1 side. The winding start end 61a of the conducting wire is adjacent to the lower movable side support 22 of the lower leaf spring 20A on the Y1 side, and the winding start 61a and the lower movable side support 22 are soldered. The winding end 61b of the conducting wire wound around the protrusion 19b on the Y2 side and the lower movable side support portion 22 of the lower leaf spring 20B on the Y2 side are also soldered in a state where they are adjacent to each other. As a result, the lower leaf spring 20A is conducted to the winding start end 61a of the conducting wire, and the lower leaf spring 20B is conducted to the winding termination 61b.

As shown in FIG. 3, the conductive plate 25A is overlapped and joined (welded) to the attachment portion 21a of the lower leaf spring 20A, and the conductive plate 25B is overlapped and joined (welded) to the attachment portion 21a of the lower leaf spring 20B. Therefore, the connection terminal 27 of the conductive plate 25A is electrically connected to the winding start end 61a of the coil 60 through the lower plate spring 20A, and the connection terminal 27 of the conductive plate 25B is wound of the coil 60 through the lower plate spring 20B. Conduction is made to the end 61b.

As shown in FIGS. 2 and 3, a spring fixing surface 10 a is provided on the upper surface of the cylindrical portion 13 of the lens holding member 10 facing in the Z1 direction. After the support member 50, the upper leaf spring 30, and the magnet M are fixed inside the case 3, the lens holding member 10, the lower leaf springs 20A and 20B, the conductive plates 25A and 25B, and the support base on which the coil 60 is wound. An assembly 70, in which 40 and 40 are assembled, is inserted into the case 3 from below. The spring fixing surface 10a of the lens holding member 10 abuts against the lower movable upper supporting portion 32 of the upper leaf spring 30 inside the case 3, and the spring fixing surface 10a and the upper movable supporting portion 32 are bonded. It is fixed by the agent. The support base 40 and the case 3 are also fixed to each other by an adhesive.

As shown in FIG. 2 and FIG. 3, a gap between the outer surface of the cylindrical portion 13 of the lens holding member 10 and the coil 60 in a portion where the restriction projection 12 of the outer portion of the lens holding member 10 does not exist. (S) is formed. The gaps (S) are formed at four locations on the outer side of the lens holding member 10. When the lens holding member 10 is housed inside the case 3 and the upper end portion of the lens holding member 10 and the upper movable side support portion 32 of the upper leaf spring 30 are fixed, the peripheral portion of the opening 3 b of the case 3 The opposing yoke part 3c bent downward from the place enters the inside of the gap (S). Therefore, the magnetized surface Mg of the magnet M is opposed to the outside of the coil 60, and the opposing yoke portion 3c is opposed to the inside of the coil 60.

As shown in FIG. 3, the lower elastic arms 23 provided on the lower leaf springs 20A and 20B are formed in a thin curved shape, that is, in a meandering shape, and are provided on the upper leaf spring 30 as shown in FIG. The upper elastic arm 33 is also formed into a thin curved shape, that is, a meandering shape. Although lower plate springs 20A and 20B and upper plate spring 30 have substantially the same plate thickness size, as shown in FIG. 9, the lower plate spring is lower than the width dimension of upper elastic arm 33 provided on upper plate spring 30. The width dimension of the lower elastic arm portion 23 provided on the plate springs 20A and 20B is reduced. That is, the cross-sectional area of the lower elastic arm 23 is smaller than the cross-sectional area of the upper elastic arm 33. Therefore, the spring constant of the lower elastic arm 23 is smaller than the spring constant of the upper elastic arm 33. The length of the upper elastic arms 33 and the lower elastic arms 23 are made different from each other, or the plate thickness of the upper leaf springs 30 and the lower leaves 20A and 20B are made different from each other. The spring constant of the lower elastic arm 23 may be set smaller than the spring constant.

FIG. 5 shows a cross section of the lens driving device 1 in the initial state in which the coil 60 is not energized. The upper surface of the lens holding member 10 is located above the lower surface of the support member 50 (in the Z1 direction) inside the frame-shaped support member 50. Therefore, the upper leaf spring 30 is fixed to the spring fixing surface 10 a of the upper surface of the lens holding member 10 more than the upper fixed supporting portion 31 bonded to the spring fixing surface 55 of the lower surface of the support member 50. The side support portion 32 is moved (displaced) by a distance H in the Z1 direction which is a direction away from the support base 40. Therefore, the upper elastic arm portion 33 is bent and the lens holding member 10 is urged toward the support base 40 in the Z2 direction by the elastic force of the upper elastic arm portion 33 of the upper plate spring 30. .

As shown in FIG. 3, stopper projections 45 a and 45 b are integrally formed on the upper surface of the support base 40 facing in the Z1 direction. Each of the two stopper protrusions 45a is located in the space 29 between the lower fixed side support 21 and the lower movable side support 22 of the lower leaf springs 20A and 20B, as shown in FIG. The upper surfaces of the stopper projections 45a are substantially flush with the upper surfaces of the lower leaf springs 20A and 20B. One stopper projection 45b is located between the two lower leaf springs 20A and 20B, and the upper surface of the stopper projection 45b is also located approximately flush with the upper surfaces of the lower leaf springs 20A and 20B. .

In the initial state shown in FIG. 5, the lower surface of the lens holding member 10 is in contact with the stopper projections 45a and 45b by the biasing force of the upper leaf spring 30, but the lower leaf springs 20A and 20B support their respective lower fixed side supports The portion 21 and the lower movable side support portion 22 are located on the same plane parallel to a plane (XY plane) perpendicular to the optical axis O. Therefore, in the initial state, almost no deflection occurs in the lower elastic arm portion 23. That is, in the initial state in which the coil 60 is not energized, the biasing force that the lower elastic arm 23 urges the lens holding member 10 toward the support base 40 causes the upper elastic arm 33 to support the lens holding member 10 It is smaller than the biasing force for biasing the base 40.

Further, each of the two stopper projections 45a is positioned in the space 29 between the lower fixed side supporting portion 21 and the lower movable side supporting portion 22 of the lower leaf springs 20A and 20B, and one stopper protruded portion By positioning 45b between the two lower leaf springs 20A and 20B, the stopper projection can be disposed within the limited facing area of the support base 40 and the lower leaf springs 20A and 20B, It becomes easy to miniaturize the lens drive device 1.

In contrast to the above embodiment, the stopper projections 45a and 45b are formed on the lower surface of the lens holding member 10, and the positions of the tips (lower surface) of the stopper projections 45a and 45b in the initial posture shown in FIG. However, the lower plate springs 20A and 20B may be configured to correspond to the height position along the Z direction of the lower surface of the lower leaf springs 20A and 20B. Furthermore, the stopper projections 45 a and 45 b may be formed separately from the support base 40 or the lens holding member 10 and fixed to the support base 40 or the lens holding member 10. When the stopper projection is provided on the support base 40 or the lens holding member 10, the tip of the stopper projection may not be located on the same plane as the upper surface or the lower surface of the lower leaf springs 20A and 20B. Absent.

Next, the operation of the lens drive device 1 of the above structure and the camera module using the same will be described.
As shown in FIG. 5, in the initial state in which no drive current is applied to the coil 60, the deflection of the lower elastic arms 23 of the lower leaf springs 20A, 20B is almost zero or slight, while the upper The deflection of the upper elastic arm 33 of the plate spring 30 is large. Moreover, the spring constant of the lower elastic arm 23 is set smaller than the spring constant of the upper elastic arm 33. Therefore, the lower elastic arm portion 23 biases the lens holding member 10 toward the support base 40 than the biasing force with which the upper elastic arm portion 33 biases the lens holding member 10 toward the support base 40. The power is smaller. Since the biasing force that the lower leaf springs 20A and 20B give to the lens holding member 10 is small, the lower surface of the lens holding member 10 is mainly at the three positions of the support base 40 by the biasing force of the upper leaf spring 30 in the initial posture. It will be pressed against the provided stopper protrusions 45a, 45b. Therefore, the lower surface of the lens holding member 10 comes into contact with the three stopper projections 45a and 45b with certainty, and the vertical position of the lens holding member 10 is maintained with reference to the stopper projections 45a and 45b. Becomes possible.

Further, the mounting portions 21a and 21b formed at both ends of the lower fixed side supporting portion 21 of the lower leaf springs 20A and 20B are fixed in contact with the spring fixing surfaces 41A and 41B formed on the support base 40. . The support base 40 is injection-molded from a synthetic resin material, and the mutual flatness of the four spring fixing surfaces 41A and 41B is maintained high. The lower fixed side supporting portion 21 is installed on the spring fixing surfaces 41A and 41B, whereby the flatness of the lower leaf springs 20A and 20B can be maintained high, and the lens holding member 10 is formed by the lower leaf springs 20A and 20B. It becomes possible to support without tilting the optical axis O which coincides with the central axis of the cylindrical portion 13.

When a drive current is applied to the connection terminals 27 and 27 protruding from the support base 40, the drive current flows through the pair of lower leaf springs 20A and 20B to the coil 60 between the winding start end 61a and the winding end 61b. The lens holding member 10 is driven in the optical axis direction (Z1 direction) by the electromagnetic force of the drive current flowing through the coil 60 and the magnetic field generated from the magnet M. By the operation of the lens holding member 10, the lens body held by the lens holding member 10 focuses the image formed on the imaging device.

Since the spring constant of the lower elastic arm 23 is smaller than the spring constant of the upper elastic arm 33, in the initial state, it is possible to reliably return the lower surface of the lens holding member 10 to the posture in which the stopper projections 45a and 45b abut Become.

As shown in FIG. 5, the upper portion of the lens holding member 10 is inserted into the inside of the frame-shaped support member 50, and the upper surface of the lens holding member 10 is positioned above the lower surface of the support member 50. It is possible to make the drive device 1 thinner. Since there is a limit in reducing the dimension h of the support member 50 in the vertical direction, when the thickness is reduced, the penetration dimension of the lens holding member 10 inside the frame shape of the support member 50 is large. Thus, in the upper leaf spring 30, the height distance H between the upper fixed side support portion 31 and the upper movable side support portion 32 is increased, and the amount of deflection of the upper elastic arm portion 33 is increased. Therefore, the biasing force of the upper leaf spring 30 to bias the lens holding member 10 toward the support base 40 is increased.

However, in the lens drive device 1 of the embodiment, the spring constant of the lower elastic arms 23 of the lower leaf springs 20A and 20B is smaller than the spring constant of the upper elastic arms 33, and in the initial state, the lower leaf spring 20A. 20B make the biasing force for biasing the lens holding member 10 toward the support base 40 smaller than the biasing force for the upper leaf spring 30 to bias the lens holding member 10 toward the support base 40. . Therefore, it is possible to suppress an increase in the biasing force which is the sum of the biasing force by the upper plate spring 30 and the biasing force by the lower plate springs 20A and 20B, and even if the deflection of the upper elastic arm 33 is increased, The spring resistance at the time of operating the lens holding member 10 in the optical axis direction can be reduced. Therefore, it becomes possible to operate the lens holding member 10 in the optical axis direction with power saving.

Next, a method of manufacturing the lens driving device 1 will be described.
First, a process of manufacturing a semi-finished product (referred to as a case block) in which the support member 50, the upper plate spring 30, and the magnet M are fixed inside the case 3 will be described. As shown in FIG. 8, the support projection 56 formed on the corner support 52 of the support member 50 is inserted between the corner facing portion 31 b of the upper leaf spring 30 and the upper elastic arm 33, The support member 50 and the upper leaf spring 30 are combined. The support member 50 and the upper leaf spring 30 are installed on the inner side (Z2 side) of the ceiling portion 3a of the case 3 in the case 3 in a posture in which the ceiling portion 3a is directed downward under the action of gravity. However, in this installation step (arrangement step), the support member 50 may be installed first in the case 3 and then the upper leaf spring 30 may be installed in the case 3. The upper leaf spring 30 installed in the case 3 is supported in a state where the side facing portion 31 a is in contact with a spring fixing surface 55 formed on the support member 50.

A fluid thermosetting adhesive is applied to the surface facing the Z 2 side at both end portions of the side surface facing portion 31 a of the upper leaf spring 30 (first application step). The applied adhesive enters the gap between the outer edge of the upper fixed support 31 of the upper leaf spring 30 and the inner surface of the case 3 and flows down by gravity, and the case contact 53 of the support member 50 and the ceiling Get in between 3a. The adhesive also enters between the spring fixing surface 55 of the support member 50 and the side facing portion 31 a of the upper leaf spring 30 by capillary action. In addition, a part of the adhesive remains in the gap between the outer edge of the upper leaf spring 30 and the inner surface of the case 3.

Next, a fluid thermosetting adhesive is applied to the inner surface in the vicinity of the boundary between the side wall 3 d and the corner wall 3 e of the case 3 (second application step). Each of the four magnets M is placed on the four corner wall portions 3e by magnetically attracting the adhesive surface Mb to the inner surface of the side wall portion 3d. At this time, an adhesive is interposed between the adhesive surface Mb and the inner surface of the case 3. The four magnets M are positioned in the case 3 by bringing the upper surface Mc into contact with the magnet contact portion 57 formed on the corner support portion 52 of the support member 50.

After the adhesive application step, the process proceeds to the heating step, and adhesion is located between the case 3 and the support member 50, and between the spring fixing surface 55 of the support member 50 and the side facing portion 31a of the upper leaf spring 30. The agent and the adhesive interposed between the magnet M and the inner surface of the case 3 are all simultaneously heat cured. As a result, as shown in FIG. 6, the support member 50 and the upper fixed side support portion 31 of the upper flat spring 30 and the four magnets M are fixed inside the case 3.

Thus, the process of manufacturing the case block is completed. In the present embodiment, the step of bonding and fixing the support member 50 and the upper fixed side support portion 31 of the upper leaf spring 30 to the inside of the ceiling portion 3a of the case 3 and bonding and fixing the inner surface of the case 3 and the magnet M. The bonding and fixing step may be performed in two parts, for example, using a UV (ultraviolet) curable adhesive as one adhesive.

In the first application process and the second application process, the same adhesive application process (supply process) is performed between the case 3 and the support member 50, the spring fixing surface 55 of the support member 50, and the upper flat spring 30. An adhesive may be supplied between the side facing portion 31 a and between the magnet M and the inner surface of the case 3. For example, after a large amount of adhesive is applied to the inner surface of the case 3, the magnet M is magnetically attracted to the inner surface of the case 3, and the magnet M is slid toward the ceiling 3a until it abuts on the magnet contact portion 57. The moving force of the magnet M at this time allows the adhesive to flow between the case 3 and the support member 50 and between the spring fixing surface 55 and the side facing portion 31 a of the upper flat spring 30. And it transfers to a heating process (adhesion fixation process) after that. In addition, at least the installation process, the application process of the adhesive, and the heating process constitute the manufacturing process of the case block, and these processes were directed under the action of gravity on the ceiling 3a of the case 3. Try to do it in attitude.

Next, the manufacturing process of the assembly 70 will be described.
As shown in FIG. 10, in the process of manufacturing the assembly 70, a leaf spring blank 120 and a conductive plate blank 125 are used. The leaf spring blank 120 is obtained by etching a metal plate having a spring property. However, the leaf spring blank 120 may be punched out of a metal plate. The outer shapes of the lower leaf spring 20A and the lower leaf spring 20B are formed on the leaf spring blank 120. The connecting branch 121b is continuous from the mounting portion 21b on the X1 side of the lower leaf spring 20A, and the connecting branch 121b is also continuous from the mounting portion 21b on the X1 side of the lower leaf spring 20B. The support plate portion 122b is continuous with the portion 121b. Similarly, the connecting branch 121a is continuous from the attachment portion 21a on the X2 side of the lower leaf spring 20A, and the connecting branch 121a is continuous from the attachment portion 21a on the X2 side of the lower leaf spring 20B. The support plate portion 122a is continued to the portions 121a and 121a. Accordingly, the lower leaf spring 20A and the lower leaf spring 20B are connected via the connecting branch portions 121a and 121b and the support plate portions 122a and 122b.

The support plate portion 122a and the support plate portion 122b are strip-shaped plate portions continuous in the Y1-Y2 direction. The support plate portion 122a and the support plate portion 122b extend in the Y1-Y2 direction, and a plurality of lower leaf springs 20A and 20B are spaced in the Y1-Y2 direction from the common support plate portion 122a and the support plate portion 122b. Are connected. A feed hole 123a is formed in the support plate portion 122a, and a feed hole 123b is formed in the support plate portion 122b, and the support plate portions 122a and 122b are sent in the Y direction using the feed holes 123a and 123b. The individual lower leaf springs 20A, 20B are sequentially fed according to a plurality of assembly processes.

The conductive plate blank 125 is formed of a conductive metal plate, and the outer shape of the two conductive plates 25A and 25B is punched out. The connecting branches 121 are continuous from the conductive plates 25A and 25B, and the supporting plate 122 is continuous to each connecting branch 121. The support plate portion 122 is a strip-shaped plate portion and extends continuously in the Y1-Y2 direction, and a plurality of conductive plates 25A and 25B are connected to the same support plate portion 122 at intervals in the Y1-Y2 direction. Feed holes 123 are formed in the support plate portion 122. In the conductive plate blank 125, the conductive plates 25A and 25B are provided with connection terminals 27 which are bent at the edge of the support plate portion 26 and project in the Z2 direction.

As shown in FIG. 4, the mounting holes 22a formed on the X1 and X2 sides of the lower movable side support portion 22 of the lower leaf spring 20A are fitted to the protrusions 10c on the lower surface of the lens holding member 10, and the protrusions 10c are formed. Heat-shrink. At the same time, the mounting holes 22a formed on the X1 and X2 sides of the lower movable side supporting portion 22 of the lower leaf spring 20B on the Y2 side are fitted to the projections 10d on the lower surface of the lens holding member 10 to thermally crimp the projections 10d. Do. As a result, the lower movable side supporting portion fixing step of fixing the lower movable side supporting portions 22 of the lower leaf springs 20A and 20B to the spring fixing surface 10b of the lens holding member 10 is performed. The lower movable side supporting portion fixing step may be performed before the fixing step of the lower fixed side supporting portion to be described later and the conductive plate, and in the present embodiment, the lower leaf springs 20A and 20B It is done in the supported state.

As a process before or after the lower movable support fixing process for fixing the lower movable support 22 of the lower leaf springs 20A and 20B supported by the leaf spring blank 120 to the lens holding member 10 A lamination step is performed in which the support plate portions 26 of the conductive plates 25A and 25B of the conductive plate blank 125 are stacked on the attachment portions 21a and 21a on the X2 side which is the lower fixed side support portions 21 of the springs 20A and 20B. In this stacking step, the support plate portion 26 of the conductive plates 25A and 25B is superimposed on the Z1 side (upper surface side) of the mounting portion 21a of the lower leaf springs 20A and 20B. At this time, the support plate portion 26 and the mounting portion 21a are positioned with reference to the hole 28 formed in the support plate portion 26 and the mounting hole 24a formed in the mounting portion 21a. Following this stacking step, a welding step (joining step) is performed in which the stacked attachment portion 21a and the support plate portion 26 of the conductive plates 25A and 25B are joined by welding. In this welding process, the laser spot is irradiated to the mounting portion 21a having a small plate thickness from the Z2 side toward the Z1 direction, and the mounting portion 21a and the support plate portion 26 are welded.

Since the plate thickness of the lower plate springs 20A and 20B is smaller than the plate thickness of the conductive plates 25A and 25B, the laser is irradiated to the overlapping portion of the mounting portion 21a and the support plate portion 26 from the lower plate springs 20A and 20B side. By melting the attachment portions 21a and 21a of the lower leaf springs 20A and 20B and securely welding the overlapping portions of the attachment portions 21a and 21a and the support plate portions 26 and 26 of the conductive plates 25A and 25B. it can.

After the welding process, a fixing process (a fixing process of the lower fixed side supporting portion and the conductive plate) of fixing the plate spring blank 120 and the conductive plate blank 125 to the support base 40 is performed. However, when the lower movable side support fixing process is not performed at the end of the welding process, the lower movable side support fixing process is performed before the fixing process. In this fixing step (the fixing step of the lower fixed side support portion and the conductive plate), the attachment portion 21a on the X2 side of the lower leaf springs 20A, 20B and the support plate portion of the conductive plates 25A, 25B overlapped and welded thereto. 26 is installed on the spring fixing surface 41A of the support base 40, the positioning projection 42a is inserted into the mounting hole 24a and the hole 28, and the mounting portion 21b of the lower leaf springs 20A and 20B on the X1 side is used as a support base. It is installed on the spring fixing surface 41B of the base 40, and the positioning projection 42b is inserted into the mounting hole 24b. Then, an adhesive is applied to each of the positioning projections 42a and 42b, and the lower fixed support 21 and the conductive plates 25A and 25B are fixed to the support base 40 with the adhesive. At this time, the mounting portion 21a of the lower fixed side support portion 21 is disposed between the upper surface (spring fixing surface 41A) of the support base 40 and the support plate portion 26 of the conductive plates 25A and 25B.

The connection terminals 27 of the conductive plates 25A and 25B are inserted into the through holes 43 formed in the support base 40, and the through holes 43 are filled with the adhesive from the Z1 side. If necessary, a caulking deformation portion is formed at the tip of the positioning projection 42a before the adhesive is applied to the positioning projection 42a, and the mounting portion 21a and the support plate 26 are fixed to the support base 40. . Further, the positioning projection 42 b and the mounting portion 21 b are also fixed to the caulking deformation portion of the positioning projection 42 b by an adhesive. By using a thermosetting adhesive as the adhesive filled in the through holes 43 and the adhesive applied to the positioning projections 42a and 42b, curing of these adhesives can be simultaneously performed by heating. Thus, the lower fixed side support portions 21 of the lower leaf springs 20A and 20B and the support plate portions 26 of the conductive plates 25A and 25B are disposed and fixed on the spring fixing surfaces 41A and 41B of the support base 40. The fixing process ends.

By the completion of the fixing step, the lens holding member 10 provided with the plate spring blank 120, the conductive plate blank 125 and the coil 60 can be mounted on the support base 40. At this time, the lower surface of the lens holding member 10 is in contact with the stopper projections 45 a and 45 b formed on the support base 40. Further, the lower movable side support portions 22 of the lower leaf springs 20A and 20B fixed to the lower portion of the lens holding member 10 and the lower fixed side support portions 21 supported by the support base 40 are positioned on the same plane in the Z direction. In the lower elastic arm portion 23, almost no deflection occurs.

Next, a cutting process of the connecting branch is performed. In this cutting step, the overlapping portion of the connecting branch 121a of the plate spring blank 120 extending to the X2 side and the connecting branch 121 of the conductive plate blank 125 is simultaneously cut, and the plate spring blank extending to the X1 side The 120 connecting branches 121 b are cut. At the end of the cutting process, the assembly fabrication process is completed, and the assembly 70 shown in FIG. 2 is completed. The connecting branches 121a and 121b and the connecting branch 121 are cut using a mechanical cutting tool or cut using a laser cutter.

As described above, after the fabrication of the assembly 70 is completed, and after the case 3 (case block) in which the support member 50, the upper leaf spring 30, and the magnet M are fixed inside, the assembly 70 is completed. A combination process is performed to combine case 3 and case 3. In addition, although the manufacturing process of the semi-finished product (case block) in which the support member 50, the upper leaf spring 30, and the magnet M are fixed inside the case 3 and the manufacturing process of the assembly 70, either may be performed first. Preferably, both preparation steps are performed in parallel.

In the combining step, an assembly 70 in which the support base 40, the lower leaf springs 20A and 20B, the conductive plates 25A and 25B, the lens holding member 10 and the coil 60 are combined together is the support member 50 and the upper leaf spring 30. The magnet M is inserted from the lower side (Z2 side) into the case 3 fixed. Alternatively, the case 70 is placed on the assembly 70 from the upper side so that the assembly 70 is inserted into the case 3. Thereby, the upward spring fixing surface 10 a of the lens holding member 10 abuts on the lower surface of the upper movable side support portion 32 of the upper leaf spring 30, and the upper elastic arm 33 of the upper leaf spring 30 is bent. Then, in this state, the spring fixing surface 10a provided on the upper portion of the lens holding member 10 and the upper movable side support portion 32 are fixed with an adhesive. Further, the support base 40 and the case 3 are also fixed to each other by an adhesive, and the lens driving device 1 is completed.

In addition, an adhesive such as thermosetting which fixes the spring fixing surface 10a and the upper movable side support portion 32 is previously applied to the spring fixing surface 10a, for example, before combining the assembly 70 and the case 3. However, after the assembly 70 and the case 3 are combined, an adhesive may be applied in the vicinity of the overlapping portion of the spring fixing surface 10 a and the upper movable side support portion 32 through the opening 3 b of the case 3 . When the adhesive is applied using the opening 3 b as described above, the lens holding member 10 and the upper leaf spring 30 are fixed after the support base 40 and the case 3 are fixed with an adhesive such as thermosetting. It is possible to fix it with an adhesive. The curing of these adhesives takes place by heating.

When the assembly 70 and the case 3 are combined, the upper movable side support portion 32 of the upper leaf spring 30 is abutted against the upper portion of the lens holding member 10 and pushed up in the Z1 direction, as shown in FIG. The upper movable side support portion 32 is located above the support base 40 by a distance H from the upper fixed side support portion 31, and the upper elastic arm portion 33 is bent in an initial state. That is, by combining the assembly 70 and the case 3, the step of raising the upper movable side support portion 32 and causing the upper elastic arm portion 33 of the upper plate spring 30 to bend is performed. Further, in a state where the assembly 70 and the case 3 are combined, the spring fixing surface 10a and the upper movable side support portion 32, and the support base 40 and the case 3 are respectively fixed to each other by an adhesive. It is possible to maintain the state in which the arm 33 is bent. In the combination process, no deflection in the initial state occurs in the lower elastic arm portions 23 of the lower leaf springs 20A and 20B.

It should be noted that after the lower movable side support fixing step described above, a conduction connecting step is performed in which the lower movable side support 22 of the lower leaf springs 20A and 20B and the winding start end 61a and the winding end 61b of the coil 60 are electrically connected by solder or the like Is going. The configuration of the conduction connection has been described above with reference to FIG. 4 and thus the detailed description thereof is omitted here. This conduction connection step may be performed before the fixing step of the lower fixed side support portion and the conductive plate.

In the embodiment, as shown in FIG. 4, the winding start end 61a and the winding end 61b of the conductive wire constituting the coil 60 are wound around the projections 19a and 19b on the lower surface of the lens holding member 10 and are wound. The portion and the lower leaf springs 20A and 20B are soldered and conducted. However, according to the present invention, even if the winding start end 61a and the winding end 61b of the wire extending from the coil 60 are directly connected to the lower leaf springs 20A and 20B by soldering or a conductive adhesive. Good.

DESCRIPTION OF SYMBOLS 1 lens drive device 3 case 3a ceiling part 3b opening part 3d side wall part 3e square surface wall part 10 lens holding member 10a, 10b spring fixing surface 20A, 20B lower leaf spring 21 lower fixed side support 22 lower movable side support 23 lower Elastic arms 25A, 25B conductive plate 26 support plate 27 connection terminal 30 upper plate spring 31 upper fixed side support 31a side facing portion 31b square surface facing portion 32 upper movable side support 33 upper elastic arm 40 support base 41A , 41B Spring fixing surface 42a, 42b Positioning projection 45a, 45b Stopper projection 50 Support member 51 Side support 52 Corner support 53 Case contact portion 55 Spring fixing surface 57 Magnet contact portion 60 Coil 70 Assembly M Magnet O light axis

Claims (19)

1. A support base, a case covering the support base, a lens holding member at least a part of which is located inside the case and capable of mounting a lens body, and the lens holding member in the optical axis direction of the lens body Upper and lower leaf springs movably supported, a coil mounted on the lens holding member, a magnet provided inside the case and facing the coil, fixed inside the ceiling of the case A support member, and
   A lower fixed support and a lower movable support, and a lower elastic arm connecting the lower fixed support and the lower movable support are integrally formed on the lower leaf spring, the lower The fixed side support portion is fixed to the support base side, and the lower movable side support portion is fixed to the lower portion of the lens holding member,
   In the upper leaf spring, an upper fixed side support portion and an upper movable side support portion, and an upper elastic arm portion connecting the upper fixed side support portion and the upper movable side support portion are integrally formed. The fixed side support portion is fixed to the lower portion of the support member, and the upper movable side support portion is fixed to the upper portion of the lens holding member,
   In the lens driving device in which the lens holding member is in contact with the support base directly or through another member in an initial state in which the coil is not energized.
   The upper movable side support portion of the upper leaf spring is positioned at an upper position away from the support base than the upper fixed side support portion, and the upper elastic arm portion is bent.
   In the initial state, the lower elastic arm portion directs the lens holding member toward the support base than a biasing force in which the upper elastic arm portion biases the lens holding member toward the support base. A lens driving device characterized in that a biasing force for biasing is smaller.
2. The lens drive device according to claim 1, wherein a spring constant of the lower elastic arm portion is smaller than a spring constant of the upper elastic arm portion.
3. The lens drive device according to claim 2, wherein a cross-sectional area of the lower elastic arm portion is smaller than a cross-sectional area of the upper elastic arm portion.
4. The said support member is frame shape, The upper part of the said lens holding member is located in the inside of the said frame shape, and is located above the lower part of the said support member in any one of Claim 1 thru | or 3. Lens drive device.
5. The said lower fixed side support part of the said lower leaf | plate spring and the said lower movable side support part are located in the same plane perpendicular | vertical to an optical axis in the said initial state. Lens drive device.
6. A stopper projection for bringing the lower portion of the lens holding member into contact with the support base in the initial state is formed on any of the lower portion of the lens holding member and the support base, The lens driving device according to claim 5, wherein the stopper projection is positioned between the lower fixed side supporting portion and the lower movable side supporting portion.
7. Spring fixing surfaces are formed at a plurality of locations on the upper surface of the support base,
   A pair of lower leaf springs is provided, and the lower fixed side supporting portions of the lower leaf springs are supported on the spring fixing surface,
   The lens drive device according to any one of claims 1 to 6, wherein a conductive plate is superimposed on the lower fixed side support portion of each lower leaf spring, and a connection terminal is formed on the conductive plate.
8. The lens driving device according to claim 7, wherein the lower fixed side support portion and the conductive plate are welded, and the lower fixed side support portion of the lower plate spring is bonded to the support base.
9. A lens drive device according to any one of claims 1 to 8, a lens body held by the lens holding member of the lens drive device, and an image pickup device facing the lens body. Camera module.
10. A support base, a case covering the support base, a lens holding member at least a part of which is located inside the case and capable of mounting a lens body, and the lens holding member in the optical axis direction of the lens body Upper and lower leaf springs movably supported, a coil mounted on the lens holding member, a magnet provided inside the case and facing the coil, fixed inside the ceiling of the case A support member, and
    A lower fixed support and a lower movable support, and a lower elastic arm connecting the lower fixed support and the lower movable support are integrally formed on the lower leaf spring. The lower fixed side support portion is fixed to the support base side, and the lower movable side support portion is fixed to the lower portion of the lens holding member,
    In the upper leaf spring, an upper fixed side support portion and an upper movable side support portion, and an upper elastic arm portion connecting the upper fixed side support portion and the upper movable side support portion are integrally formed, The upper fixed side support portion is fixed to the lower portion of the support member, and the upper movable side support portion is fixed to the upper portion of the lens holding member,
    In a method of manufacturing a lens driving device in which the lens holding member is in contact with the support base directly or through another member in an initial state in which the coil is not energized.
    (A) positioning the upper movable side support portion of the upper plate spring above the support base with respect to the upper fixed side support portion to cause deflection in the upper elastic arm portion;
    (B) fixing the upper movable side support portion and the upper portion of the lens holding member;
    Have
    In the initial state, the lower elastic arm portion directs the lens holding member toward the support base than a biasing force in which the upper elastic arm portion biases the lens holding member toward the support base. A method of manufacturing a lens driving device, wherein the biasing force to be biased is set smaller.
11. Before the step (a),
    Bonding and fixing the support member and the upper fixed side support portion of the upper leaf spring inside the ceiling portion of the case;
    Bonding and fixing the magnet to the inner surface of the case;
    Attaching the lower leaf spring and the lens holding member having the coil on the support base to produce an assembly;
    Have
    In the step (a), by combining the assembly and the case such that the assembly is inserted into the case, the upper portion of the lens holding member and the upper movable portion of the upper leaf spring are movable. The method for manufacturing a lens drive device according to claim 10, wherein the upper elastic arm portion is caused to bend by bringing a side support portion into contact with the side support portion.
12. The method according to claim 11, wherein the support member has a frame shape, and an upper portion of the lens holding member is positioned above the lower portion of the support member in the frame shape.
13. In the same heating step, the support member, the adhesive for fixing the upper fixed support of the upper leaf spring, and the adhesive for fixing the magnet to the inner surface of the case, inside the ceiling of the case The method for manufacturing a lens driving device according to claim 11 or 12, wherein the resin is cured by
14. The method according to any one of claims 10 to 13, wherein a spring constant of the lower elastic arm is smaller than a spring constant of the upper elastic arm.
15. The method for manufacturing a lens driving device according to claim 14, wherein a cross-sectional area of the lower elastic arm is formed smaller than a cross-sectional area of the upper elastic arm.
16. The lower fixed side support portion and the lower movable side support portion of the lower leaf spring are located on the same plane perpendicular to the optical axis in the initial state. Method of manufacturing lens drive device.
17. A stopper projection is formed on any one of the lower portion of the lens holding member and the support base for bringing the lower portion of the lens holding member into contact with the support base in the initial state, and at least a part of the stopper protrusion The method for manufacturing a lens drive device according to claim 16, wherein the lens unit is positioned between the lower fixed side support portion and the lower movable side support portion.
18. Before the step (a),
    (C) using the pair of conductive plates having connection terminals and the pair of lower leaf springs, and stacking the lower fixed side supporting portion of each lower leaf spring and the conductive plate;
    (D) welding the lower fixed side supporting portion and the conductive plate respectively stacked in the step (c);
    (E) The lower fixed side welded in the step (d) on the support base so that the lower fixed side support portion is disposed between the support base and the conductive plate Arranging and fixing a support portion and the conductive plate, respectively;
    The manufacturing method of the lens drive device in any one of the Claims 10 thru | or 17 which have these.
19. The thickness of the conductive plate is greater than the thickness of the lower leaf spring,
    In the step (d), the lower fixed side support portion and the conductive plate are irradiated with a laser from the lower fixed side support portion to the overlapping portion of the lower fixed side support portion and the conductive plate. The manufacturing method of the lens drive device of Claim 18 which welds.

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