KR20110097553A - Lens driving device and assembling method thereof - Google Patents

Abstract

To avoid complicating the shape of the housing for electrode attachment.
The lens drive device 10 includes a lens holder 18 including a cylindrical portion 182 holding a lens barrel, and a housing 12 supporting the lens holder 18 so as to be movable only in the optical axis O direction. ), Moving means for moving the lens holder 18 in the optical axis O direction, and guide means for guiding the lens holder 18 so as to be movable only in the optical axis O direction. The moving means comprises a shape memory alloy member 32 spanned between the lens holder 18 and the housing 12. On both ends of the shape memory alloy member 32, a pair of electrodes 34 for energizing it are attached. The housing 12 includes an actuator base 14 disposed on the lower side of the lens holder 18, and an electrode holder 22 attached to the actuator base 14 to hold the pair of electrodes 34. Include.

Description

Lens driving device and assembly method thereof {LENS DRIVING DEVICE AND ASSEMBLING METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens driving apparatus, and more particularly, to a lens driving apparatus using a shape memory alloy in an actuator and a method of assembling the same.

Background Art [0002] A linear actuator using a shape memory alloy (SMA) is known as an autofocus actuator or a zoom actuator of a camera.

For example, WO2007 / 113478A1 (Patent Document 1) discloses a camera lens driving device for driving the movement of one camera lens supported by one support structure (housing) by one suspension system. The camera lens driving device disclosed in Patent Document 1 mounts a subassembly having an SMA wire connected to at least one mounting member mounted on a support structure. At least two SMA wires are held with tension between the camera lens element and the support structure (housing) at an acute angle, respectively, with respect to the tensioning optical axis with components along the optical axis. The two SMA wires are held at an angle when viewed along the optical axis. The subassembly has an attachment member to which the SMA wire is connected by caulking. The attachment member is electrically connected to the SMA wire. Thus, the attachment member functions as an electrode. The attachment member (electrode) is attached to the depression formed in the support structure (annular wall).

Moreover, Unexamined-Japanese-Patent No. 2007-292864 (patent document 2) discloses the lens drive apparatus which improved the transmission efficiency and aimed at compactness. The lens driving device disclosed in Patent Document 2 includes a fixed barrel (housing), a lens frame (lens holder) holding part or all of a lens group (lens barrel) constituting the optical system, and a lens frame (lens) for the fixed barrel. Guide means for freely supporting the holder in the optical axis direction, and pressing means for pressing the lens frame toward one of the optical axis directions. The lens drive device moves the lens frame to the other side against the pressing of the pressing means against the fixed barrel.

The lens drive device disclosed in Patent Document 2 includes a shape memory alloy (SMA) wire and a wire bearing member. Both ends of the SMA wire are fixed to the fixed barrel and are heated by energization to reduce the length of the predetermined relaxation state. The shape memory alloy wire returns to the length of a relaxed state when cooled by the energization stop. The wire bearing member is attached to the lens frame, and the action part set between the both ends of the shape memory alloy wire is caught so that the convex part may be in the direction of the curved shape toward one side.

In the embodiment of the lens driving apparatus disclosed in Patent Document 2, both ends of the SMA wire are fixed to a pair of wire support members, and the pair of wire support members is fixed to a fixing barrel (housing). The energization control part energizes both ends of an SMA wire through a pair of wire support members. Thus, the wire support member functions as an electrode.

Moreover, Japanese Patent Laid-Open No. 2007-78954 (Patent Document 3) discloses a lens tilt configured to move an imaging lens in an optical axis direction using a shape memory alloy. The lens tilt disclosed in Patent Document 3 uses a shape memory alloy formed in a band shape with an imaging lens (lens barrel) for forming an object light and a mirror frame (lens holder) for holding the imaging lens (lens barrel). The imaging lens is moved in a predetermined direction. A part of the shape memory alloy is disposed in the optical path of the imaging lens (lens barrel), and the mirror frame (lens holder) is moved by shrinking the shape memory alloy by energization. Patent document 3 also discloses that a pair of diaphragm type leaf springs are provided in the optical axis direction both ends of a mirror frame (lens holder) as an embodiment of lens tilting.

In the embodiment of the lens tilt disclosed in Patent Document 3, both ends of the shape memory alloy formed in the form of a band are squeezed and fixed by a pair of plate members to a columnar portion (housing) standing up from a fingerboard. The shape memory alloy is energized through the plate member. Thus, the plate member functions as an electrode.

Japanese Laid-Open Patent Publication No. 2009-19507 (Patent Document 4) discloses a drive module and a method of assembling which allow the variation in the assembly accuracy to be reduced while improving the production efficiency. The driving module disclosed in Patent Document 3 is hooked to an intermediate portion of a shape memory alloy (SMA) wire that is moved on a chassis (housing; support) so that a driven member (lens holder) is stretched in accordance with the amount of energization. The drive module has a pair of holding terminals, and the chassis (housing) has a positioning portion and a step portion. Each holding terminal has a wire holding part for holding the end of the SMA wire so as to be conductive, a positioning portion for the support, and a catch portion receiving a reaction force from the support toward the positioning portion. The positioning section hangs the positioning section of the holding terminal. The stepped part hangs the latched part of the holding terminal toward the position to be positioned. The holding terminal functions as an electrode because it is an energized portion.

WO2007 / 113478A1 Japanese Patent Publication No. 2007-292864 Japanese Patent Publication No. 2007-78954 Japanese Patent Publication No. 2009-19507

The above-mentioned patent documents 1-4 have the problem as demonstrated below, respectively.

In the camera lens driving apparatus disclosed in Patent Document 1, the attachment member (electrode) for the shape memory alloy wire is directly attached to one support structure. As a result, the shape of the support structure becomes complicated for electrode attachment. In addition, it is difficult to disassemble the product at the time of poor characteristics, making it difficult to reuse the parts.

Also in the lens drive device disclosed in Patent Document 2, a pair of wire support members (electrodes) for SMA wires are directly fixed to a fixing barrel (housing). As a result, the shape of the fixed barrel (housing) becomes complicated for electrode attachment. In addition, it is difficult to disassemble the product at the time of poor characteristics, making it difficult to reuse the parts.

In the lens tilt disclosed in Patent Document 3, a pair of plate members (electrodes) are directly fixed to the columnar portions (housings). As a result, the shape of the housing is complicated for electrode attachment. In addition, it is difficult to disassemble the product at the time of poor characteristics, making it difficult to reuse the parts.

In the drive module disclosed in Patent Document 4, a pair of holding terminals (electrodes) for SMA wire are attached directly to the chassis (housing). As a result, the shape of the chassis (housing) is complicated for electrode attachment. In addition, it is difficult to disassemble the product at the time of poor characteristics, making it difficult to reuse the parts.

Moreover, all patent documents 1-4 use the shape memory alloy wire formed linearly as a shape memory alloy member. As a result, there is a limit to the amount of lens displacement of the lens driving apparatus. In other words, the amount of lens displacement of the lens driving apparatus depends on the amount of displacement of the shape memory alloy wire.

Therefore, the subject of this invention is providing the lens drive apparatus which can simplify the shape of the support body (actuator base) which supports a shape memory alloy member, and its assembly method.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lens driving apparatus capable of easily disassembling a product at the time of poor characteristics and reusing parts, and a method of assembling the same.

Another object of the present invention is to provide a lens driving apparatus capable of significantly increasing the amount of lens displacement.

Other objects of the present invention will become clear as the description proceeds.

According to the first aspect of the present invention, the lens holder 18 including the cylindrical portion 182 holding the lens barrel 11 and the lens holder 18 are movable only in the optical axis O direction. A lens having a housing 12 for supporting, a moving means for moving the lens holder 18 in the optical axis O direction, and a guide means for guiding the lens holder 18 so as to be movable only in the optical axis O direction. In the drive device (10; 10A; 10B), the moving means comprises a shape memory alloy member (32; 32A; 32B-1, 32B-2) sandwiched between the lens holder (18) and the housing (12). On both ends of the shape memory alloy members 32; 32A; 32B-1 and 32B-2, a pair of electrodes 34; 34B-1 and 34B-2 for energizing it are attached, and the housing 12 is a lens. An electrode base 14 disposed on the lower side of the holder 18 and an electrode holder attached to the actuator base 14 to hold the pair of electrodes 34; 34B-1 and 34B-2 ( Which contains 22) A lens driving device which is characterized by obtained.

In the lens drive device (10; 10A; 10B) according to the first aspect of the present invention, the lens holder (18) protrudes radially outward from the cylindrical portion (182) to form the shape memory alloy member (32; 32A). It is preferable to have the step protrusions 184; 184B-1 and 184B-2 for hanging the intermediate portions 32a; 32Aa; 32B-1a and 32B-2a of; 32B-1 and 32B-2. The guiding means may include, for example, elastic members 26 and 28 disposed between the lens holder 18 and the housing 12. In this case, the elastic members 26 and 28 support the lens holder 18 so as to be displaceable only in the optical axis O direction with the lens holder 18 positioned in the radial direction. The elastic member is preferably composed of an upper leaf spring 26 and a lower leaf spring 28 provided on the upper side and the lower side in the optical axis O direction of the cylindrical portion 182 of the lens holder 18, respectively. The upper leaf spring 26 has, for example, an upper ring portion 262 attached to the upper end of the lens holder 18, four upper ends 264 attached to the housing 12, an upper ring portion and four upper ends. What is necessary is just to consist of four upper arm parts 266 connecting each. The lower leaf spring may consist of a pair of lower leaf springs 28. In that case, each of the pair of lower leaf springs 28 is, for example, a lower arc portion 282 attached to the lower end of the lens holder 18 and a pair of lower ends 284 fixed to the housing 12. ) And a pair of lower arm portions 286 connecting the lower arc portion and the pair of lower ends. The shape memory alloy member may be constituted by the shape memory alloy wire 32 formed in a linear shape. Instead, the shape memory alloy member may be constituted by the shape memory alloy members 32A; 32B-1 and 32B-2 formed in a coil shape. Step projections 184; 184B-1; 184B-2 are arranged in plural on the outer circumferential wall of the tubular portion 182 at equiangular intervals about the optical axis O, and the shape memory alloy members 32B-1, 32B. -2 may be arranged in the same number as the number of the step protrusions 184; 184B-1; 184B-2, and may be hung on each of the step protrusions 184; 184B-1; 184B-2.

According to the second aspect of the present invention, the upper leaf spring 26 and the lower leaf spring are provided at both ends in the optical axis O direction of the lens holder 18 having the cylindrical portion 182 for holding the lens barrel 11. A first step of attaching (28), and an attaching member (22, 24; 24B) to which the shape memory alloy assemblies (36; 36A; 36B-1, 36B-2) are attached to the lens holder (18). 2nd process, the 3rd process of attaching the actuator base 14 to the support members 22, 24 and 24B in the state which inserted the lower leaf spring 28 from the bottom side of the lens holder 18, and a lens holder. The fourth step of attaching the inner upper cover 30 to the support members 22, 24 and 24B in a state where the upper leaf spring 26 is fitted from the upper side of the 18, and the inner upper cover 30 is covered. A method of assembling the lens drive device (10; 10A; 10B) including the fifth step of covering the outer wound cover (16) is obtained.

In the assembling method of the lens driving device (10; 10A; 10B) according to the second aspect of the present invention, the shape memory alloy assembly (36; 36A; 36B-1, 36B-2) comprises: a shape memory alloy member (32); 32A; 32B-1, 32B-2 and a pair of electrodes 34; 34B-1, 34B-2 electrically connected to both ends of the shape memory alloy member, and the lens holder 18 It has opposite first and second sides, and on the first side has step projections 184; 184B-1 and 184B-2, which project outwardly from the outer wall of the cylindrical portion 182, and the support members face each other. It consists of the 1st and 2nd support members 22, 24; 24B which are provided, and is a shape in the state which hold | maintained the pair of electrodes 34; 34B-1, 34B-2 in the 1st support member 22. The memory alloy assemblies 36; 36A; 36B-1, 36B-2 may be attached. In this case, the second step is a step (184; 184B-1) of the intermediate portions (32a; 32Aa; 32B-1a, 32B-2a) of the shape memory alloy members (32; 32A; 32B-1, 32B-2). ; 184B-2, so that the shape memory alloy members 32; 32A; 32B-1 and 32B-2 are interposed between the lens holder 18 and the first support member 22, and the first support member ( Attaching 22 to the first side of the lens holder 18; and attaching the second support members 24 and 24B to the second side of the lens holder 18.

The upper leaf spring 26 has an upper ring portion 262 and four upper ends 264 provided at four corners and having an upper spring hole 264a, and four upper sides connecting the upper ring portion and four upper ends. The lower leaf spring may be composed of a pair of lower leaf springs 28, and each of the pair of lower leaf springs has a lower arc portion 282 and a lower end hole 284a. The branch may be composed of a pair of lower end portions 284 and a pair of lower arm portions 286 connecting the lower arc portion and the pair of lower ends. In this case, the first step is to attach the upper ring portion 262 of the upper leaf spring 26 to the upper end of the cylindrical portion 182 of the lens holder 18, and the pair of lower leaf springs 28. Attaching the lower circular arc portion 282 to the lower end portion of the cylindrical portion 182 of the lens holder 18.

Each of the first and second support members 22, 24; 24B has a pair of support protrusions 224, 244; 244B at both ends thereof, and each of the pair of support protrusions has a support protrusion at an upper end thereof. 224a, 244a). In this case, the second process uses the support projections 224a and 244a of the first and second support members 22, 24 and 24B to respectively open the upper end holes of the four upper ends 264 of the upper leaf spring 26. It embeds in the step 264a.

The actuator base 14 has a ring-shaped base portion 14 and four base protrusions 142 protruding upward from the four corners of the base portion, and the four base protrusions each have four base protrusions upwardly. You may have the protrusion 142a. In this case, the said 3rd process uses the four base protrusions 142a formed in the four base protrusions 142 of the actuator base 14, respectively, and a pair of lower end parts 284 of the pair of lower leaf springs 28 respectively. In the state where the lower end hole 284a formed in the upper side is passed, the four base protrusions 142 of the actuator base 14 are each pair of protrusions of the first and second support members 22, 24 and 24B, respectively. (224, 244; 244B).

The inner upper cover 30 has a ring-shaped inner cover body 302 and four step protrusions 304 protruding downward from the four corners of the inner cover body, each of the four step protrusions having a through hole. You may have 304a. In this case, the fourth process supports the first and second support members 22, 24, and 24B which protrude through the upper end holes 264a of the four upper ends 264 of the upper leaf springs 26. The protrusions 224a and 244a are inserted into the through holes 304a formed in the four step protrusions 304 of the inner upper cover 30, respectively, to the first and second supporting members 22, 24 and 24B. The inner upper cover 30 is attached.

In addition, the code | symbol in the said parentheses is attached in order to make understanding easy, It is a matter of course that it is only an example and is not limited to these.

In the present invention, since the housing includes an actuator base disposed on the lower side of the lens holder and an electrode holder attached to the actuator base to hold a pair of electrodes, a support (actuator base) supporting the shape memory alloy member ) Can be simplified. In addition, the product can be easily disassembled in the case of poor characteristics, and the parts can be reused.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which looked at the external appearance of the lens drive apparatus which concerns on 1st Embodiment of this invention at an oblique front upward.
FIG. 2 is a perspective view, as viewed obliquely from above, omitting the lens barrel from the lens driving apparatus shown in FIG.
FIG. 3 is a perspective view of the lens drive device shown in FIG. 2, with the outer side cover omitted, and viewed obliquely from above.
4 is an exploded perspective view of the lens driving device illustrated in FIG. 2 as viewed obliquely from above.
FIG. 5 is a front view of the lens driving apparatus shown in FIG. 3.
FIG. 6 is a perspective view of the state in which the SMA assembly shown in FIG. 5 is attached to the electrode holder as viewed obliquely from above.
FIG. 7 is a perspective view of the state shown in FIG. 6 as viewed obliquely from above.
8 is a perspective view of the state in which the elastic member is attached to the lens holder as viewed obliquely from above.
FIG. 9 is a perspective view of the state shown in FIG. 8 as viewed obliquely from below.
FIG. 10A is a perspective view of the flow of the first assembly process of the lens driving device shown in FIG. 2 as viewed obliquely from above.
FIG. 10B is a perspective view of the flow of the second assembling step of the lens driving device shown in FIG. 2, seen obliquely from above.
FIG. 10C is a perspective view of the flow of the third assembling process of the lens driving device illustrated in FIG. 2, seen obliquely from above.
FIG. 10D is a perspective view of the flow of the fourth assembling process of the lens driving device illustrated in FIG. 2, viewed obliquely from above.
Fig. 11 is a perspective view, viewed obliquely from the front, omitting the lens barrel and the outer cover from the lens driving apparatus according to the second embodiment of the present invention.
FIG. 12 is a front view of the lens driving device shown in FIG. 11.
FIG. 13 is a perspective view of the SMA assembly shown in FIG. 11 attached to the electrode holder as viewed obliquely from the rear.
Fig. 14 is a perspective view showing a lens holder and an SMA assembly used in the lens driving apparatus according to the third embodiment of the present invention.
15 is an exploded perspective view of the lens driving apparatus according to the third embodiment of the present invention as viewed obliquely from above.
It is a perspective view seen obliquely from the front upward, omitting the outer side cover from the lens driving apparatus according to the fourth embodiment of the present invention.
FIG. 17 is a perspective view of the actuator base, the elastic member, and the electrode holder, seen obliquely from the front and upward from the lens drive device shown in FIG. 16.
18 is an exploded perspective view of the lens driving apparatus according to the fourth embodiment of the present invention as viewed obliquely from above.
19 is a front view of the lens driving device shown in FIG. 17.
20 is a top view of the lens driving device shown in FIG. 17.
FIG. 21 is a perspective view of the lens drive device according to the fifth embodiment of the present invention, with the outer side cover omitted and viewed obliquely from above.
FIG. 22 is a perspective view of the actuator base, the elastic member, and the electrode holder, seen obliquely from the front and upward from the lens drive device shown in FIG. 16.
Fig. 23 is an exploded perspective view of the lens driving device according to the fifth embodiment of the present invention as viewed obliquely from above.
24 is a front view of the lens driving device shown in FIG. 22.
FIG. 25 is a side view of the lens driving device shown in FIG. 22.
FIG. 26 is a top view of the lens driving device shown in FIG. 22.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

With reference to FIGS. 1-5, the lens drive apparatus 10 which concerns on 1st Embodiment of this invention is demonstrated. 1 is a perspective view of the lens driving apparatus 10 as viewed obliquely from above. FIG. 2 is a perspective view of the lens drive device 10 viewed obliquely from above in a state where the lens barrel 11 is omitted. 3 is a perspective view of the lens driving device 10 viewed obliquely from above in a state where the lens barrel 11 and the outer cover 16 are omitted. 4 is an exploded perspective view of the lens driving device 10 viewed obliquely from above in a state where the lens barrel 11 is omitted. FIG. 5 is a front view of the lens driving apparatus 10 with the lens barrel 11, the outer cover 16, and the inner cover (stopper) 30 omitted.

Here, as shown in Figs. 1 to 5, rectangular coordinate systems (X, Y, Z) are used. 1 to 5, in the Cartesian coordinate system (X, Y, Z), the X axis direction is the front-rear direction (depth direction), the Y axis direction is the left-right direction (width direction), and the Z axis The direction is the vertical direction (height direction). In the example shown in FIGS. 1-5, the up-down direction Z is the optical axis O direction of a lens. In addition, in this specification, a front direction is also called a 1st side and a rear direction is also called a 2nd side.

In the actual use situation, however, the optical axis O direction, that is, the Z axis direction is the front-rear direction. In other words, the upper direction of the Z axis is the forward direction, and the lower direction of the Z axis is the rear direction.

The illustrated lens drive device 10 passes through the optical axis O and has a surface symmetrical structure with respect to the (extended) plane defined by the front-rear direction X and the vertical direction Z. As shown in FIG.

The illustrated lens driving device 10 is provided in, for example, a mobile phone with an autofocusable camera. The lens driving apparatus 10 includes a lens barrel (lens assembly) 11 in which an autofocus lens AFL, which is a movable lens, is incorporated. The lens driving device 10 is for moving the lens barrel 11 only in the optical axis O direction.

As shown in FIG. 1, the lens driving device 10 includes an approximately rectangular parallelepiped body (housing) 12 covering the lens barrel 11. In other words, the lens barrel 11 is arranged in the housing (housing) 12. The housing (housing) 12 includes an actuator base 14 and an outer wound cover 16.

In addition, although not shown in figure, the imaging element arrange | positioned at the board | substrate is mounted in the center part of the actuator base 14. This imaging element picks up an image of an object formed by the movable lens AFL and converts it into an electrical signal. The imaging device is configured by, for example, a charge coupled device (CCD) type image sensor, a complementary metal oxide semiconductor (CMOS) type image sensor, or the like.

The lens driving device 10 includes a lens holder 18 holding the lens barrel 11. In other words, the lens barrel 11 is held and fixed in the lens holder 18. In detail, the lens holder 18 includes the cylindrical part 182 which has a substantially cylindrical shape. A female screw (not shown) is formed on the inner circumferential wall of the cylindrical portion 182 of the lens holder 18. On the other hand, the outer circumferential wall of the lens barrel 11 is formed with a male screw (not shown) that is screwed to the female screw. Therefore, in order to mount the lens barrel 11 to the lens holder 18, the lens barrel 11 is rotated about the optical axis O with respect to the lens holder 18, and the lens barrel 11 is screwed along the optical axis O direction. 11 is housed in the lens holder 18 and bonded to each other by an adhesive or the like.

The lens holder 18 is supported in the housing 12 so as to be movable only in the optical axis O direction as described later. The lens movable parts 11 and 18 are formed by the combination of the lens barrel 11 and the lens holder 18.

The outer circumferential wall of the cylindrical portion 182 of the lens holder 18 has a protrusion 184 protruding radially outward from the front of the front-back direction X. The protruding portion 184 protrudes along the vertical direction Z from the upper end of the cylindrical portion 182 toward the lower end. This protrusion 184 is for hooking the intermediate portion 32a of the shape memory alloy wire 32 formed in a linear shape to be described later. Therefore, the protrusion 184 is also referred to as a step protrusion.

The actuator base 14 has a ring-shaped base portion 142 and four base protrusions 144 that slightly protrude upward in the vertical direction Z from the four corners of the base portion 142. The four base protrusions 144 each have four base protrusions 144a which protrude upwards. A front recess 146 is formed between the two base protrusions 144 in front of the four base protrusions 144, and a rear recess 148 is formed between the two base protrusions 144 in the rear. .

The housing (housing) 12 further has a front support member 22 and a rear support member 24. The front support member 22 is attached to the front of the actuator base 14, and the rear support member 24 is attached to the rear of the actuator base 14. The front support member 22 and the rear support member 24 have substantially the same shape. The front support member 22 and the rear support member 24 pass through the optical axis O and are arranged in surface symmetry with respect to the (extended) plane defined by the left and right directions Y and the up and down directions Z. . In other words, the front support member 22 and the rear support member 24 are in a mirror relationship with respect to the plane.

The front support member 22 is also called the first support member, and the rear support member 24 is also called the second support member. The first and second support members are also collectively referred to as support members.

In addition, since the front support member 22 is for holding a pair of electrodes 34 mentioned later, it is also called an electrode holder.

The front support member (electrode holder) 22 is a front base portion 222 inserted into the front recess 146 of the actuator base 14 and a pair of base projections in front of the actuator base 14 ( A pair of anterior support protrusions 224 mounted on 144 and a pair of anterior support connections 226 connecting between both ends of the anterior base portion 222 and the pair of anterior support protrusions 224. . The pair of anterior support protrusions 224 protrude upwards and each has a pair of anterior support protrusions 224a protruding upwards. In addition, although not shown, the pair of anterior support protrusions 224 have a pair of anterior support holes into which the pair of base protrusions 144a which protrude from the anterior pair of base protrusions 144 are inserted in the bottom part. Has As described below, the pair of electrodes 34 are retained by a pair of front support connections 226.

Similarly, the rear support member 24 includes a rear base portion 242 inserted into the rear recess 148 of the actuator base 14, and a pair of base protrusions 144 behind the actuator base 14. It has a pair of rear support protrusions 244 mounted thereon and a pair of rear support connection portions 246 that connect between both ends of the rear base portion 242 and the pair of rear support protrusions 244. The pair of rear support protrusions 244 protrude upwards and each have a pair of rear support protrusions 244a protruding upwards. On the other hand, although not shown, the pair of rear support protrusions 244 has a pair of rear support holes into which a pair of base protrusions 144a protruding from the rear pair of base protrusions 144 is inserted at the bottom thereof. Has

The lens driving device 10 includes an upper leaf spring 26 and a pair of lower leaf springs 28 provided on the upper and lower sides in the optical axis O direction of the cylindrical portion 182 of the lens holder 18, respectively. do. The upper leaf spring 26 and the pair of lower leaf springs 28 are disposed between the lens holder 18 and the housing 12, and the optical axis O in the state where the lens holder 18 is positioned in the radial direction. It functions as the elastic member 20 which supports so that displacement is possible in the direction.

As described above, in the actual use situation, the upper direction in the Z axis direction (optical axis O direction) is the forward direction, and the lower direction in the Z axis direction (optical axis O direction) is the rear direction. Accordingly, the upper leaf spring 26 is also referred to as the front spring, and the pair of lower leaf springs 28 is also referred to as the rear spring.

The upper leaf spring 26 is disposed above the optical axis O direction in the lens holder 18, and the pair of lower leaf springs 28 is below the optical axis O direction in the lens holder 18. Is placed.

The upper leaf spring 26 has an upper ring portion 262 attached to the lens holder 18 and four upper ends 264 attached to the four corners of the housing 12 as described below. Four upper arm portions 266 are provided between the upper ring portion 262 and the four upper end portions 264. That is, the four upper arm portions 266 connect the upper ring portion 262 and the four upper end portions 264.

The upper ring portion 262 of the upper leaf spring 26 is fixed to the cylindrical portion 182 of the lens holder 18. In detail, the lens holder 18 has four upper holder protrusions 186 projecting radially outward from the upper end of the cylindrical portion 182. The four upper holder protrusions 186 each have four upper holder protrusions 186a which protrude upwards. The upper ring portion 262 of the upper leaf spring 26 has four upper spring holes 262a into which these four upper holder protrusions 186a are respectively inserted.

On the other hand, the four upper ends 264 of the upper leaf springs 26 are a pair of front support protrusions 224 of the front support member 22 and a pair of rear support protrusions 244 of the rear support member 24. Is fixed to. In detail, the four upper ends 264 of the upper leaf springs 26 each have a pair of front support protrusions 224a and a pair of rear support protrusions 244 formed on the pair of front support protrusions 224. 4 has four upper end holes 264a into which a pair of rear support protrusions 244a are formed. The housing 12 further has a resin inner inner cover 30 provided inside the outer outer cover 16. The upper upper ends 264 of the upper leaf springs 26 are fixed by the inner upper cover 30.

In detail, the inner upper cover 30 includes a ring-shaped inner cover body 302, four stepped protrusions 304 slightly projecting downward from the four corners of the inner cover body 302, and the front side. A pair of front extensions 306 extending downwardly in the vicinity of the pair of projections 304, and a pair of rear extensions 308 extending downward in the vicinity of the rear pair of projections 304. It is composed of The four gait protrusions 304 each have four through holes 304a into which a pair of front protrusions 224a of the anterior support member 22 and a pair of rear support protrusions 244a of the rear support member 24 are inserted. ) Accordingly, the four upper end portions 264 of the upper leaf springs 26 may include four step protrusions 304 of the inner upper cover 30, a pair of front support protrusions 224 of the anterior support member 22, and It is fixed in a state sandwiched between the pair of rear support protrusions 244 of the rear support member 24. The inner upper cover 30 is also referred to as a stopper because it has a function of preventing the upper leaf spring 26 from escaping from the front support member 22 and the rear support member 24.

Thus, the housing 12 is composed of an actuator base 14, an outer outer cover 16, a front support member (electrode holder) 22, a rear support member 24, and an inner upper cover (stopper) 30. It is composed.

One of the pair of lower leaf springs 28 is provided on the right side in the left and right directions Y, and the other is provided on the left side in the left and right directions Y. The pair of lower leaf springs 28 pass through the optical axis O and are arranged in plane symmetry with respect to the plane (extended) defined by the front-rear direction X and the vertical direction Z. As shown in FIG. In other words, one side and the other of the pair of lower leaf springs 28 are in mutual relation with each other with respect to the plane.

The lower leaf spring 28 on the right side has a lower arc portion 282 extending in an arc shape in the front-rear direction X from the right side, and a pair of lower end portions 284 provided at two edges in the front-rear direction X on the right side. Has A pair of lower arm parts 286 is provided between the lower arc part 282 and the pair of lower end parts 284. That is, the pair of lower arm portions 286 connect the lower arc portion 282 and the pair of lower end portions 284. The pair of lower end portions 284 have a pair of lower end holes 284a into which the pair of base protrusions 144a provided on the right side of the four base protrusions 144a of the actuator base 14 are fitted. Accordingly, the pair of lower end portions 284 of the lower leaf spring 28 on the right side have a pair of base protrusions 144 on the right side of the actuator base 14 and the front protrusions on the right side of the anterior support member 22. It is sandwiched and fixed between the 224 and the rear protrusion 244 on the right side of the rear support member 24. The lower arc portion 282 of the lower leaf spring 28 on the right side is attached to the right side of the lower end of the cylindrical portion 182 of the lens holder 18.

Similarly, the lower leaf spring 28 on the left side has a lower arc portion 282 extending in an arc shape in the front-rear direction X from the left side, and a pair of lower end portions provided at two edges in the front-rear direction X on the left side ( 284). A pair of lower arm parts 286 is provided between the lower arc part 282 and the pair of lower end parts 284. That is, the pair of lower arm portions 286 connect the lower arc portion 282 and the pair of lower end portions 284. The pair of lower end portions 284 have a pair of lower end holes 284a into which a pair of base protrusions 144a provided on the left side of the four base protrusions 144a of the actuator base 14 are fitted. Therefore, the pair of lower end parts 284 of the lower left leaf spring 28 on the left side are the pair of base protrusions 144 on the left side of the actuator base 14 and the front protrusions on the left side of the anterior support member 22. It is sandwiched and fixed between 224 and the rear projection 244 on the left side of the rear support member 24. The lower arc portion 282 of the lower leaf spring 28 on the left side is attached to the left side of the lower end of the cylindrical portion 182 of the lens holder 18.

The elastic member 20 which consists of the upper leaf spring 26 and the pair of lower leaf springs 28 functions as a guide means which guides the lens holder 18 so that it can move only to the optical axis O direction. Each of the upper leaf spring 26 and the pair of lower leaf springs 28 is made of metal such as beryllium copper, phosphor bronze, stainless steel, and the like. These upper leaf springs 26 and lower leaf springs 28 are manufactured by press working on a predetermined thin plate or by etching using photolithography techniques. Moreover, etching process is more preferable than press working. This is because no residual stress remains in the etching process.

With such a configuration, the lens movable parts 11 and 18 can move only in the optical axis O direction with respect to the housing (housing) 12.

The lens drive device 10 includes a shape memory alloy wire 32 formed in a linear shape disposed near the outer wall of the cylindrical portion 182 of the lens holder 18, and both ends of the shape memory alloy wire 32, respectively. A pair of electrodes 34 electrically connected are provided. The combination of the shape memory alloy (SMA) wire 32 and the pair of electrodes 34 is referred to as the shape memory alloy (SMA) assembly 36. The SMA assembly 36 is held on the front support member (electrode holder) 22 as described below.

6 and 7, the attachment state to the front support member (electrode holder) 22 of the SMA assembly 36 will be described. FIG. 6 is a perspective view of the SMA assembly 36 attached to the electrode holder 22 as viewed obliquely from above. FIG. 7 is a perspective view of the SMA assembly 36 attached to the electrode holder 22 as viewed obliquely from the rear.

The pair of electrodes 34 has a symmetrical shape. The pair of electrodes 34 extend substantially in the vertical direction (Z). Each electrode 34 has a substantially L-shaped supported portion 342 held at the front support connecting portion 226, a connecting portion 344 bent in a cross-section c-shaped at an upper end of the supported portion 342, and a supported portion 342 It has a band-shaped terminal portion 346 extending downward from the inner end of. Each electrode 34 caulks the connecting portion 344 and is electrically connected to an end portion of the shape memory alloy wire 32. The terminal portion 346 is for receiving supply of driving current from a driving circuit (not shown).

As shown in FIG. 6, the supported portion 342 of the electrode 34 is held at the back of the front support connection 226 of the electrode holder 22. The supported portion 342 has a circular hole 342a.

As shown in FIG. 7, the front support connecting portion 226 has a cylindrical first protrusion 226a projecting rearward from the rear surface thereof so as to fit in the circular hole 342a of the supported portion 342. Moreover, the front support connecting part 226 has the 2nd protrusion part 226b which protrudes back from the back surface so that it may engage with the bottom surface part of the to-be-supported part 342. As shown in FIG. Further, the front support connecting portion 226 has a third triangular prism 226c having a substantially triangular prism projecting rearward from its rear surface to be engaged with the L-shaped inner bent portion of the supported portion 342. In addition, the outer surface of the supported portion 342 of the electrode 34 is caught by the inner wall of the front support protrusion 224 of the electrode holder 22.

In this way, the SMA assembly 36 is attached to the front support member (electrode holder) 22. On the other hand, the intermediate portion 32a of the shape memory alloy wire 32 is engaged with the protrusion (step projection) 184 of the lens holder 18. That is, the shape memory alloy wire 32 spans between the lens holder 18 and the housing 12.

Next, a schematic operation of the lens driving device 10 will be described.

As is well known, the "shape memory alloy" is a metal having a property in which a given strain distortion becomes zero in a specific temperature range and is restored to its original shape. The shape memory alloy is made of, for example, a TiNi alloy.

In addition, the shape memory alloy wire 32 shown in the figure is contracted to a pre-stored contraction length when self-heating by energization, and returns to a predetermined original length (length of relaxation state) by natural cooling when the energization is stopped. Is the wire.

The elastic member 20 acts to press the lens holder 18 downward along the optical axis O direction. On the other hand, the shape memory alloy wire 32 is contracted when it is energized from the drive circuit (not shown) through the pair of electrodes 34. As a result, the lens holder 18 moves upward along the optical axis O direction against the pressing force in the downward direction of the elastic member 20.

On the other hand, when the energization to the shape memory alloy wire 34 is stopped, the shape memory alloy wire 32 is naturally cooled. As a result, the shape memory alloy wire 32 is extended by the downward force of the elastic member 20. As a result, the lens holder 18 moves downward along the optical axis O direction.

That is, the shape memory alloy wire 32 is stretched and contracted in the optical axis O direction by the temperature change caused by the energization / non-energization, and functions as a moving means for moving the lens holder 18 in the optical axis O direction.

The combination of the elastic member 20 and the SMA assembly 36 supports the lens movable parts 11 and 18 so as to be movable in the optical axis O direction, while driving the lens movable parts 11 and 18. Function as

The lens drive units 20 and 36 and the lens movable units 11 and 18 are arranged side by side with respect to the optical axis O as shown in FIG. 5. Therefore, the lens drive device 10 can be reduced in size.

Next, with reference to FIGS. 8-10D, the assembly method of the lens drive apparatus 10 is demonstrated. 8 is a perspective view of the state in which the elastic member 20 is attached to the lens holder 18 as viewed obliquely from above. 9 is a perspective view of the state in which the elastic member 20 is attached to the lens holder 18 as viewed obliquely from below. 10A to 10D are perspective views showing the flow of the first to fourth assembling processes of the lens driving apparatus 10 as viewed obliquely from above.

As shown in FIG. 8 and FIG. 9, first, the elastic member 20 is attached to the lens holder 18.

In this state, the upper ring portion 262 of the upper leaf spring 26 is fixed to the upper end of the cylindrical portion 182 of the lens holder 18 as shown in FIG. 8. At this time, the four upper holder protrusions 186a formed in the four upper holder protrusions 186 protruding from the upper end of the cylindrical portion 182 are inserted into the four upper spring holes 262a formed in the upper ring portion 262. It is.

As shown in FIG. 9, the lower circular arc portions 282 of the pair of lower leaf springs 28 are attached to the lower ends of the cylindrical portions 182 of the lens holder 18.

10A, the front support member (electrode holder) 22, the SMA assembly 36, and the rear support member 24 are attached to the lens holder 18 to which the elastic member 20 is attached. .

In detail, first, the assembly obtained by attaching the SMA assembly 36 as shown in FIGS. 6 and 7 to the front support member (electrode holder) 22 is attached to the lens holder 18. At this time, the pair of front support protrusions 224a formed on the pair of front support protrusions 224 of the front support member (electrode holder) 22 have a pair of upper end portions of the front of the upper leaf spring 26 ( It fits into a pair of upper end hole 264a formed in 264. The middle portion 32a (see FIGS. 6 and 7) of the shape memory alloy wire 32 is caught by the protrusion (step projection) 184 of the lens holder 18. In addition, the pair of rear support protrusions 244a formed on the pair of rear support protrusions 244 of the rear support member 24 is a pair formed on the pair of upper end portions 264 behind the upper leaf springs 26. It is fitted in the upper end hole 264a of the.

Next, as shown in FIG. 10B, the actuator base 14 is attached to the front support member (electrode holder) 22 and the rear support member 24. At this time, the pair of base protrusions 144a (see FIG. 4) formed on the pair of base protrusions 144 in front of the actuator base 14 are connected to one pair of the front support members (electrode holders) 22. A pair of base protrusions 144a (see FIG. 4) inserted into a pair of anterior support holes (not shown) formed in the anterior support protrusion 224 and formed in the pair of base protrusions 144 in the rear are supported by the rear support. It is inserted into a pair of rear support holes (not shown) formed in the pair of rear support protrusions 144 of the member 24.

Subsequently, as shown in FIG. 10C, the inner upper cover 30 is attached to the front support member (electrode holder) 22 and the rear support member 24. At this time, the upper leaf spring 26 is sandwiched and fixed between the inner upper cover 30 and the front support member (electrode holder) 22 and the rear support member 24.

In detail, the pair of upper end portions 264 of the front of the upper leaf springs 26 may include a pair of the protruding portions 304 in front of the inner upper cover 30 and one of the front support members 22. It is sandwiched and fixed between the pair of anterior support protrusions 224. In addition, the pair of upper end portions 264 behind the upper leaf springs 26 includes a pair of stepped protrusions 304 at the rear of the inner upper cover 30 and a pair of rear supports of the rear support member 24. It is sandwiched and fixed between the protrusions 244.

Finally, the outer cover 16 is attached to the assembly shown in FIG. 10C as shown in FIG. 10D.

In this manner, in the present embodiment, the lens drive device 10 can be manufactured step by step. As a result, the tact to the completion of the product can be shortened and adhesion of dust can be suppressed as much as possible.

After that, the lens barrel 11 is attached to the lens holder 18 as described above.

The lens drive device 10 according to the first embodiment described above has the following effects.

Since the shape memory alloy wire 32 (SMA assembly 36) to which the pair of electrodes 34 are attached is attached to the actuator base 14 via the electrode holder 22, the actuator base 14 The shape can be simplified.

As shown in Fig. 10, the lens drive device 10 can be manufactured step by step, so that the lens drive device 10 (product) can be easily disassembled in the case of poor characteristics. As a result, the parts can be reused.

With reference to FIGS. 11-13, the lens drive apparatus 10A which concerns on 2nd Embodiment of this invention is demonstrated. 11 is a perspective view of the lens driving device 10A as viewed obliquely from above in a state where the lens barrel 11 and the outer cover 16 are omitted. FIG. 12 is a front view of the lens driving device 10A shown in FIG. 11. FIG. 13 is a perspective view of the SMA assembly attached to the electrode holder 22 viewed obliquely from the rear.

The illustrated lens drive device 10A has the same configuration as the lens drive device 10 shown in FIGS. 1 to 7 except that the configuration of the shape memory alloy member (SMA assembly) is different as described later. It works. Therefore, reference numerals 32A and 36A are attached to the shape memory alloy member and the SMA assembly, respectively. The same reference numerals are given to the same components as those of the lens driving apparatus 10, and their description is omitted, and only the differences will be described below.

32 A of shown shape memory alloy members are comprised from the shape memory alloy member formed in coil shape. The shape memory alloy member 32A shown has a length of, for example, 3 mm in a non-stretched state (natural state). On the other hand, as shown in FIG. 11 and FIG. 12, when the shape memory alloy member 32A hangs the intermediate part 32Aa over the protrusion (step projection) 184 of the lens holder 18, the shape memory The length of the alloy member 32A is, for example, 7 mm. On the other hand, the thickness (diameter) of the wire rod of the shape memory alloy member 32 is 0.05 mm.

Therefore, in the shape memory alloy wire 32 formed in a linear shape, for example, only about 4% shrinks, whereas in the shape memory alloy member 32A formed in a coil shape, it shrinks by 200% or more, for example. It is possible. Therefore, compared with the lens drive apparatus 10 which concerns on 1st Embodiment, in the lens drive apparatus 10A which concerns on 2nd Embodiment, the movable range (stroke) of the lens movable parts 11 and 18 can be lengthened.

Since the lens drive device 10A having such a configuration performs the same operation as that of the lens drive device 10 according to the first embodiment described above, the description of the operation is omitted.

In any case, the shape memory alloy member 32A is stretched and contracted in the optical axis O direction by the temperature change caused by the energization / non-energization, and functions as a moving means for moving the lens holder 18 in the optical axis O direction.

The combination of the elastic member 20 and the SMA assembly 36A allows the lens drivers 20 and 36A to drive the lens movable parts 11 and 18 while movably supporting the lens movable parts 11 and 18 in the optical axis O direction. Function as

The lens drive units 20 and 36A and the lens movable units 11 and 18 are arranged side by side with respect to the optical axis O as shown in FIG. Therefore, the lens drive device 10A can be reduced in size.

Since the assembling method of the lens driving device 10A is also the same as the assembling method of the lens driving device 10 described with reference to FIGS. 8 to 10, the description thereof will be omitted.

The lens drive device 10A according to the second embodiment described above has the following effects.

Since the shape memory alloy member 32A (SMA assembly 36A) having the pair of electrodes 34 attached thereto is attached to the actuator base 14 via the electrode holder 22, the actuator base 14 The shape can be simplified.

Since the SMA assembly 36A is attached to the actuator base 14 via the electrode holder 22, the lens drive device 10A (product) can be easily disassembled at the time of poor characteristics. As a result, the parts can be reused.

Further, since the shape memory alloy member 32A is formed in a coil shape, the entire length of the wire rod of the shape memory alloy member 32A can be lengthened as compared with the linear shape memory alloy wire 32. Therefore, the elastic force of the shape memory alloy member 32A can be improved. As a result, it becomes possible to significantly increase the lens displacement amount (stroke of the lens movable portion) of the lens drive device 10A.

With reference to FIG. 14 and FIG. 15, the lens drive apparatus 10B which concerns on 3rd Embodiment of this invention is demonstrated. 14 is a perspective view showing a lens holder and an SMA assembly used in the lens driving apparatus according to the third embodiment of the present invention, and FIG. 15 is an oblique view from above and upward of the lens driving apparatus according to the third embodiment of the present invention. Exploded perspective view.

The lens driving apparatus 10B of the third embodiment is the lens of the first embodiment shown in Figs. 1 to 7 except that the configurations of the SMA assembly, the electrode holder and the step projections (protrusions) are different as will be described later. It operates with the structure similar to the drive apparatus 10. FIG. Therefore, reference numerals 36B-1, 36B-2, and 22, 24B, and 184B-1, 184B-2 are attached to the SMA assembly, the electrode holder, and the step protrusion (projection), respectively. The same components as those of the lens driving apparatus 10 of the first embodiment are denoted by the same reference numerals, and their descriptions are omitted, and only the differences between the first embodiment and the third embodiment will be described below.

First, the step projections (projections) 184B-1 and 184B-2 which are the first of the differences between the first embodiment and the third embodiment will be described.

In the lens drive device 10 according to the first embodiment, one step projection (protrusion) 184 is provided, whereas in the lens drive device 10B according to the third embodiment, the step projection (protrusion) 184B -1, 184B-2) is provided in two places.

In detail, in the lens drive apparatus 10B which concerns on 3rd Embodiment, a pair which protrudes radially outward from the front of the front-back direction X to the outer peripheral wall of the cylindrical part 182 of the lens holder 18 is mentioned. Protruding portions 184B-1 and 184B-2 are formed. The protrusion 184B-1 is formed in front of the cylindrical portion 182, and the protrusion 184B-2 is formed behind the cylindrical portion 182. As shown in FIG. 14, the pair of protrusions 184B-1 and 184B-2 are formed at positions deviated 180 degrees from each other with respect to the optical axis O positioned at the center of the cylindrical portion 182. In other words, the pair of protrusions 184B-1 and 184B-2 pass through the optical axis O and face symmetric with respect to the plane (which extends to) defined by the left and right directions Y and the up and down directions Z. It is arranged. Each of the protrusions 184B-1 and 184B-2 protrudes in a hook shape along the up-down direction Z from the upper end side of the cylindrical portion 182 toward the lower end side. Each of the protrusions 184B-1 and 184B-2 is for hooking the intermediate portions 32B-1a and 32B-2a of the shape memory alloy wires 32B-1 and 32B-2 formed in a coil shape described later. Therefore, the protrusions 184B-1 and 184B-2 are also referred to as step protrusions.

Next, the electrode holders 22 and 24B which are the second difference between the first embodiment and the third embodiment will be described.

In the lens drive device 10 according to the first embodiment, only the front support member 22 functions as an electrode holder, whereas in the lens drive device 10B according to the third embodiment, only the front support member 22 is used. In addition, the rear support member 24B also functions as an electrode holder.

In detail, the housing (housing) 12 has the front support member 22 and the back support member 24B which function as an electrode holder. Here, since the front support member 22 in 3rd Embodiment is a structure exactly the same as the front support member 22 in 1st Embodiment, the description is abbreviate | omitted. Moreover, since the rear support member 24B in 3rd Embodiment has a structure substantially the same as the rear support member 24 in 1st Embodiment, it is the same as the rear support member 24B in 3rd Embodiment. Only the difference of the back support member 24 in 1st Embodiment is demonstrated below, and the description is abbreviate | omitted about the structure other than that.

The rear support member 24B in the third embodiment functions as an electrode holder holding the pair of electrodes 34B-2, respectively, and the supported portion 342B- of the pair of electrodes 34B-2 described later. It has the back support connection part 246B which keeps 2) in its back surface. The rear support connecting portion 246B has a cylindrical first protrusion 246Ba projecting forward from the rear surface thereof so as to fit into the circular hole 342B-2a of the supported portion 342B-2. Further, the rear support connecting portion 246B has a second protrusion 246Bb projecting forward from the rear surface thereof so as to be engaged with the bottom surface portion of the supported portion 342B-2. Further, the rear support connecting portion 246B has a third triangular prism portion 246Bc which protrudes rearward from the rear surface thereof so as to be engaged with the L-shaped inner bent portion of the supported portion 342B-2. In addition, the outer surface of the supported portion 342B-2 of the electrode 34B-2 is caught by the inner wall of the rear supporting protrusion 244B of the rear supporting member 24B.

Next, SMA assemblies 36B-1 and 36B-2 (shape memory alloy members 32B-1 and 32B-2) and electrodes 34B-1 and 34B- which are the third of the differences between the first embodiment and the third embodiment. 2)) will be described.

In the lens drive device 10 according to the first embodiment, one SMA assembly 36 (shape memory alloy member 32, a pair of electrodes 34) is provided, whereas the lens drive device 10 according to the third embodiment In the lens driving apparatus 10B, two SMA assemblies 36B-1 and 36B-2 (shape memory alloy members 32B-1 and 32B-2 and a pair of electrodes 34B-1 and 34B-2) are provided. It is installed.

In detail, the lens drive device 10B according to the third embodiment includes a first SMA assembly 36B-1 (shape memory alloy member 32B-1, a pair of electrodes 34B-1), The 2nd SMA assembly 36B-2 (shape memory alloy member 32B-2 and the pair of electrode 34B-2) comprised similarly to this 1st SMA assembly 36B-1 is provided.

The supported portion 342B-1 of the pair of electrodes 34B-1 constituting the first SMA assembly 36B-1 is connected to the front support connecting portion 226 of the electrode holder (front support member) 22. Maintained on the back. Further, the supported portion 342B-2 of the pair of electrodes 34B-2 constituting the second SMA assembly 36B-2 has a rear surface of the rear support connecting portion 246B of the electrode holder (rear support member) 24B. Is maintained at.

In the lens drive device 10 according to the first embodiment, the shape memory alloy member 32 is formed in a linear shape, whereas in the lens drive device 10B according to the third embodiment, the shape memory alloy is provided. The members 32B-1 and 32B-2 are formed in a coil shape.

In detail, the shape memory alloy members 32B-1 and 32B-2 of 3rd Embodiment are comprised by the shape memory alloy member formed in coil shape. The shape memory alloy members 32B-1 and 32B-2 shown in the figure have a length of, for example, 3 mm in an undisturbed state (natural state). On the other hand, as shown in Fig. 14, the shape memory alloy members 32B-1 and 32B-2 are formed in the middle portions 32B-1a and 32B-2a, and the projections (step projections) of the lens holder 18 ( If it hangs over 184B-1 and 184B-2, the length of shape memory alloy members 32B-1 and 32B-2 will be 7 mm, for example. In addition, the thickness (diameter) of the wire rods of the shape memory alloy members 32B-1 and 32B-2 is 0.05 mm.

Therefore, in the shape memory alloy wire 32 of the first embodiment formed in a linear shape, for example, only about 4% is contracted, but the shape memory alloy member 32B-1 of the third embodiment formed in a coil shape. , 32B-2), for example, can shrink 200% or more. Therefore, compared with the lens drive apparatus 10 which concerns on 1st Embodiment, in the lens drive apparatus 10B which concerns on 3rd Embodiment, the movable range (stroke) of the lens movable parts 11 and 18 can be lengthened.

Since the lens drive device 10B having such a configuration performs the same operation as that of the lens drive device 10 according to the first embodiment described above, the description of the operation is omitted.

In any case, the shape memory alloy members 32B-1 and 32B-2 are contracted by the temperature change caused by energization / non-energization, and the lens holder 18 is provided through the projections (steps) 184B-1 and 184B-2. It serves as a moving means for moving in the optical axis O direction.

The combination of the elastic member 20 and the SMA assemblies 36B-1 and 36B-2 drives the lens movable parts 11 and 18 while movably supporting the lens movable parts 11 and 18 in the optical axis O direction. It functions as the lens driver 20, 36B-1, 36B-2.

The lens drive units 20, 36B-1, 36B-2 and the lens movable units 11, 18 are provided side by side with respect to the optical axis O. Therefore, the lens drive device 10B can be reduced in size.

Since the assembly method of the lens drive device 10B of the third embodiment is also the same as the assembly method of the lens drive device 10 of the first embodiment described with reference to FIGS. 8 to 10, the description thereof will be omitted.

The lens drive device 10B according to the third embodiment described above has the following effects.

The shape memory alloy members 32B-1 and 32B-2 (SMA assemblies 36B-1 and 36B-2) to which the pair of electrodes 34B-1 and 34B-2 are attached are attached to the electrode holders 22 and 24B. Since it is attached to the actuator base 14 through, the shape of the actuator base 14 can be simplified.

Since the SMA assemblies 36B-1 and 36B-2 are attached to the actuator base 14 via the electrode holders 22 and 24B, the lens drive device 10B (product) can be easily disassembled in case of poor characteristics. Can be. As a result, the parts can be reused.

Since the shape memory alloy members 32B-1 and 32B-2 are formed in a coil shape, compared with the linear shape memory alloy wire 32, the entire wire rod of the shape memory alloy members 32B-1 and 32B-2. The length can be made longer. Therefore, the elastic force of the shape memory alloy members 32B-1 and 32B-2 can be improved. As a result, it becomes possible to greatly increase the lens displacement amount (stroke of the lens movable portion) of the lens drive device 10B.

Further, two step projections 184B-1 and 184B-2 are provided on the outer circumferential wall of the tubular portion 182 at equal angle intervals with respect to the optical axis O, and the step projections 184B-1. 2 SMA assemblies 36B-1 and 36B by installing two shape memory alloy members 32B-1 and 32B-2 (SMA assemblies 36B-1 and 36B-2) corresponding to 184B-2. Since -1) imparts equal propulsion force to the movable parts 11 and 18 at two front and rear directions, the lens movable parts 11 and 18 with respect to the optical axis O direction at the time of operation of the lens drive device 10B. ) Can be suppressed.

Moreover, the driving force required for each shape memory alloy member 32B-1 and 32B-2 by driving the lens movable parts 11 and 18 by the two shape memory alloy members 32B-1 and 32B-2. Since only half of this is required, wider design freedom of the shape memory alloy members 32B-1 and 32B-2 can be ensured.

In the present embodiment, the step projections (protrusions) and the shape memory alloy members are provided two by two, but the number of the step protrusions (protrusions) and the shape memory alloy members may be any of three or four. Does not matter.

With reference to FIGS. 16-20, the lens drive apparatus 10C which concerns on 4th Embodiment of this invention is demonstrated. Fig. 16 is a perspective view of the lens drive device according to the fourth embodiment of the present invention, with the outer side cover omitted, and viewed obliquely from above, and Fig. 17 shows an actuator base and an elastic member from the lens drive device shown in Fig. 16; It is a perspective view seen obliquely from the front and omits the electrode holder, and FIG. 18 is an exploded perspective view of the lens driving device according to the fourth embodiment of the present invention as viewed obliquely from the front upward, and FIG. 19 is the lens driving device shown in FIG. 20 is a top view of the lens driving device shown in FIG. 17.

The lens driving apparatus 10C of the fourth embodiment is the lens driving apparatus of the first embodiment shown in Figs. 1 to 7 except that the structures of the lens holder, the lens driving unit, and the actuator base are different as will be described later. It operates with the configuration similar to (10). Therefore, the same reference numerals are given to the same components as the components of the lens driving apparatus 10 of the first embodiment, and their descriptions are omitted, and only the differences between the first and fourth embodiments will be described below. do.

First, the lens holder 18C which is the first of the differences between the first embodiment and the fourth embodiment will be described.

While the lens holder 18 in the lens driving apparatus 10 according to the first embodiment has one step protrusion (projection portion) 184 for hanging the shape memory alloy wire 32, the fourth embodiment The lens holder 18C of the lens drive device 10C according to the present invention has two steps (projections) 184C-1 and 184C-2 for hanging the shape memory alloy wires 32C-1 and 32C-2 described later. The pressure step protrusions (protrusions) 188C-1a, 188C-1b, 188C-2a, and 188C-2b, which hang the shape-molding alloys 38C-1 and 38C-2 for pressure, which will be described later. I have a dog.

First, the step projections (projections) 184C-1 and 184C-2 will be described in detail below.

In the lens drive device 10C according to the fourth embodiment, a pair of step projections projecting radially outward from the front and rear of the front-back direction X on the outer circumferential wall of the cylindrical portion 182C of the lens holder 18C. 184C-1 and 184C-2 are formed. The step protrusion 184C-1 is formed in front of the cylindrical portion 182C, and the step protrusion 184C-2 is formed behind the cylindrical portion 182C. The pair of step protrusions 184C-1 and 184C-2 are respectively located at positions 180 ° apart from each other about the optical axis O positioned at the center of the cylindrical portion 182C as shown in FIGS. 16 to 20. Formed. In other words, the pair of step projections 184C-1 and 184C-2 pass through the optical axis O and also with respect to a plane (extended to) defined by the left and right directions Y and the up and down directions Z. It is arranged symmetrically. Each step protrusion 184C-1, 184C-2 protrudes in a hook shape along the up-down direction Z from the upper end side to the lower end side of the cylindrical portion 182C. Each of the step protrusions 184C-1 and 184C-2 is for hanging the intermediate portions 32C-1a and 32C-2a of the shape memory alloy wires 32C-1 and 32C-2 formed in a linear shape described later.

Next, the pressing step projections (projections) 188C-1a, 188C-1b, 188C-2a, and 188C-2b will be described in detail below.

Four pressing step projections 188C-1a, 188C-1b, 188C-2a protruding radially outward from the front and rear of the front-back direction X on the outer circumferential wall of the cylindrical portion 182C of the lens holder 18C. , 188C-2b). The pair of pressing step protrusions 188C-1a and 188C-1b of the four pressing step protrusions 188C-1a, 188C-1b, 188C-2a, and 188C-2b are located in front of the tubular portion 182C. Formed. The pair of pressing step projections 188C-2a and 188C-2b are formed behind the cylindrical portion 182C. The pair of pressing step protrusions 188C-1a and 188C-1b are located above the step protrusions 184C-1 in a state in which the pair of pressing step projections 188C-1a and 188C-1b are arranged side by side in the left-right direction Y. In detail, the intermediate point of the pair of pressing step protrusions 188C-1a and 188C-1b is positioned on a line extending upward along the up-down direction Z through the step protrusions 184C-1. The pair of pressing step projections 188C-1a and 188C-1b are arranged. Similarly, the pair of pressing step protrusions 188C-2a and 188C-2b are located above the step protrusions 184C-2 in a state in which the pair of pressing step protrusions 188C-2a and 188C-2b are arranged side by side in the left-right direction Y. In detail, the intermediate point of the pair of pressing step protrusions 188C-2a and 188C-2b is positioned on the line extending upward along the up-down direction Z through the step protrusions 184C-2. The pair of pressing step projections 188C-2a and 188C-2b are arranged. Each pressing step projection 188C-1a, 188C-1b, 188C-2a, 188C-2b protrudes in a hook shape along the up-down direction Z from the lower end side of the cylindrical portion 182C toward the upper end side. . Each of the pressing step projections 188C-1a, 188C-1b, 188C-2a, and 188C-2b is an intermediate portion 38C- of the pressing shape memory alloys 38C-1 and 38C-2 formed in a coil shape described later. 1a, 38C-2a).

And the lens holder 18C in the lens drive apparatus 10C which concerns on 4th Embodiment is the upper holder protrusion part formed in the lens holder 18 in the lens drive apparatus 10 which concerns on 1st Embodiment. Does not have (186)

Next, the actuator base 14C which is the second difference between the first embodiment and the fourth embodiment will be described.

In the lens drive device 10 according to the first embodiment, the electrode holder 22 and the actuator base 14 are formed separately, whereas in the lens drive device 10C according to the fourth embodiment, the electrode holding function is provided. The actuator base 14C is provided.

Specifically, the actuator base 14C of the fourth embodiment includes four first protrusions projecting upward in the vertical direction Z from the four corners of the ring-shaped base portion 142C and the base portion 142C. Between the electrode holder portion 144C and the first electrode holder portion 144C, two second electrode holder portions 146C protruding upward from the base portion 142C in the up-down direction Z are included. The four first electrode holder portions 144C have substantially the same shape. The two second electrode holder portions 146C have substantially the same shape. The four first electrode holder portions 144C are for holding the electrodes 34C-1 and 34C-2 described later and the alloy holding portions 382C-1 and 382C-2 described later. The two second electrode holder portions 146C hold the electrodes 34C-1 and 34C-2 to be described later, and position the lower leaf spring 28C to be described later in the front-rear direction X and the left-right direction Y. Is to decide.

Next, the lens driver which is the third of the differences between the first embodiment and the fourth embodiment will be described.

In the lens drive device 10 according to the first embodiment, the lens drive part is composed of a combination of the elastic member 20 and one shape memory alloy wire 32 for driving, while in the fourth embodiment. In the lens driving apparatus 10C according to the related art, the lens driving portion has an elastic member 20C, two shape memory alloy wires 32C-1 and 32C-2 for driving, and two shape memory alloys 38C- for pressure. 1, 38C-2).

First, 20 C of elastic members are demonstrated in detail below.

The elastic member 20C includes an upper leaf spring 26C disposed above the optical axis O direction of the lens holder 18C, and a lower leaf spring disposed below the optical axis O direction of the lens holder 18C. 28C). Although the upper leaf spring 26C in 4th Embodiment and the upper leaf spring 26 in 1st Embodiment have some difference in the structure, it is the same about a functional surface. Similarly, although the lower leaf spring 28C in 4th Embodiment and the lower leaf spring 28 in 1st Embodiment have some difference in the structure, it is the same about a functional surface. That is, the upper leaf spring 26C and the lower leaf spring 28C are disposed between the lens holder 18C and the housing 12, and are positioned in the optical axis O direction with the lens holder 18C positioned in the radial direction. It functions as 20 C of elastic members which can be displaceably supported. In addition, the upper leaf spring 26C and the lower leaf spring 28C are made of beryllium copper, phosphor bronze, and the like.

Next, the shape memory alloy wires 32C-1 and 32C-2 for driving will be described in detail below.

Both ends of the shape memory alloy wire 32C-1 are held by a pair of electrodes 34C-1. Both ends of the shape memory alloy wire 32C-2 are held by a pair of electrodes 34C-2. The intermediate portion 32C-1a of the shape memory alloy wire 32C-1 is caught by the step protrusion (projection portion) 184C-1. The intermediate portion 32C-2a of the shape memory alloy wire 32C-2 is caught by the step protrusion (projection portion) 184C-2. The shape memory alloy wires 32C-1 and 32C-2 for driving are formed in linear form similarly to the shape memory alloy wire 32 in the first embodiment.

Next, the two pressing shape memory alloys 38C-1 and 38C-2 will be described in detail below.

The pressing shape memory alloy 38C-1 is disposed above the shape memory alloy wire 32C-1, and the pressing shape memory alloy 38C-2 is disposed above the shape memory alloy wire 32C-2. It is. A pair of alloy holding parts 382C-1 are attached to both ends of the pressurized shape memory alloy 38C-1. A pair of alloy holding parts 382C-2 are attached to both ends of the pressurized shape memory alloy 38C-2. The alloy holding portion 382C-1 is fitted into and held in the alloy holding grooves 144Ca formed in the two first electrode holder portions 144C positioned on the front side, respectively. The alloy holding portions 382C-2 are fitted into and hold in the alloy holding grooves 144Ca formed in the two first electrode holder portions 144C positioned on the rear side, respectively. The middle portion 38C-1a of the shape memory alloy 38C-1 for pressing is hooked by two pressing step protrusions (projections) 188C-1a and 188C-1b. In the pressure shape memory alloy 38C-2, the intermediate portion 38C-2a is hung by two pressing step protrusions (projections) 188C-2a and 188C-2b. The shape memory alloys 38C-1 and 38C-2 for pressurization are not connected to the electrode and are not energized.

The two pressing shape memory alloys 38C-1 and 38C-2 are formed in a coil shape. The illustrated shape memory alloys 38C-1 and 38C-2 have a length of, for example, 3 mm in an undisturbed state (natural state). On the other hand, the shape memory alloys 38C-1 and 38C-2 for pressure are applied, and the intermediate parts 38C-1a and 38C-2a are pressurized steps (protrusions) of the lens holder 18C (protrusions) 188C-1a and 188C. When it hangs over -1b, 188C-2a, and 188C-2b, the length of the shape memory alloys 38C-1 and 38C-2 for pressurization becomes 7 mm, for example. In addition, the thickness (diameter) of the wire rod of the shape memory alloys 38C-1 and 38C-2 for pressurization is 0.05 mm.

Therefore, in the case of being formed in a linear shape, for example, only about 4% can be shrunk, whereas in the case of being formed in a coil shape, it can be shrunk by 200% or more.

The shape memory alloy wires 32C-1 and 32C-2 for driving and the shape memory alloys 38C-1 and 38C-2 for pressurization are contracted by increasing their temperature in a high temperature environment, and in a normal temperature environment. The temperature decreases and elongates. The term " high temperature environment " used herein means an environment having an external temperature of about 70 DEG C or more when a TiNi alloy is employed as the shape memory alloy. In addition, "normal temperature environment" means the environment whose external temperature is about 70 degrees C or less, for example, when TiNi alloy is employ | adopted as a shape memory alloy.

Next, the operation of the lens driving unit in the normal temperature environment, the high temperature environment, and the energization of the shape memory alloy wires 32C-1 and 32C-2 for driving will be described below.

First, under normal temperature environment, since the shape memory alloys 38C-1 and 38C-2 for pressurization do not contract as described above, the lens movable parts 11 and 18C are moved downward along the optical axis O direction. It functions as a pressurizing spring to press, and as a result, the pressing force which presses the lens movable parts 11 and 18C downward along the optical axis O direction can be adjusted.

Next, in a high temperature environment, the shape memory alloy wires 32C-1 and 32C-2 rise and contract as the temperature rises as described above. At this time, the shape memory alloys 38C-1 and 38C-2 for pressurization also increase in temperature and shrink. At this time, the lens movable portion 11, toward the upper side in the optical axis O direction, is lower than the thrust of the shape memory alloy wires 32C-1 and 32C-2 acting on the lens movable portions 11 and 18C. Since the thrust of the pressurized shape memory alloys 38C-1 and 38C-2 acting on 18C becomes larger (or becomes the same), the displacement of the lens movable parts 11 and 18C in the direction above the optical axis O is changed. You can prevent it. Thus, the shape memory alloys 38C-1 and 38C-2 for pressurization function as thrust adjustment means which adjusts the thrust acting on the lens movable parts 11 and 18C.

Next, at the time of energization of the shape memory alloy wires 32C-1 and 32C-2, the shape memory alloy wires 32C-1 and 32C-2 rise in temperature and shrink, and the step projections (projections) 184C. The lens holder 18C is moved upward in the direction of the optical axis O through -1, 184C-2. At this time, since the pressurized shape memory alloys 38C-1 and 38C-2 do not conduct electricity as described above, they function only as pressurized springs pressed downward. As a result, the lens holder 18C moves upward along the optical axis O direction against the downward pressing force of the shape memory alloys 38C-1 and 38C-2 for pressurization and the upper leaf spring 26C. . On the other hand, when the energization to the shape memory alloy wires 32C-1 and 32C-2 is stopped, the shape memory alloy wires 32C-1 and 32C-2 are naturally cooled. As a result, the shape memory alloy wires 32C-1 and 32C-2 are elongated, and the lens holder 18C is moved to the optical axis by the pressing force in the downward direction of the shape memory alloys 38C-1 and 38C-2 for pressure. O) Move downward along the direction.

The lens drive device 10C according to the fourth embodiment described above has the following effects.

The step projections (projections) (184C-1, 184C-2) are provided on the outer circumferential wall of the tubular portion (182C) at equiangular intervals centering on the optical axis O, and the step projections (projections) By providing two shape memory alloy wires 32C-1 and 32C-2 corresponding to (184C-1, 184C-2), the lens movable portions 11 and 18C are equal in two front and rear directions. Since the driving force is applied, the inclination of the lens movable parts 11 and 18C with respect to the optical axis O direction at the time of operation of the lens drive device 10C can be suppressed.

Moreover, the driving force required for each shape memory alloy wire 32C-1 and 32C-2 by driving the lens movable parts 11 and 18C by the two shape memory alloy wires 32C-1 and 32C-2. Since only half of this is required, wider design freedom of the shape memory alloy wires 32C-1 and 32C-2 can be ensured.

In addition, by providing the shape memory alloys 38C-1 and 38C-2 for pressure as the lens drive unit, the pressing force for pressing the lens movable parts 11 and 18C downward along the optical axis O direction in the normal temperature environment is adjusted. Not only can it be possible, but also the displacement of the lens movable parts 11 and 18C in the optical axis O direction can be prevented under a high temperature environment.

The pressure shape memory alloys 38C-1 and 38C-2 are formed in a coil shape, so that the shape for pressure is higher than shrinkage of the shape memory alloy wires 32C-1 and 32C-2 in a high temperature environment. Since the shrinkage of the memory alloys 38C-1 and 38C-2 increases and the driving force in the downward direction along the optical axis O increases, the displacement of the lens movable portions 11 and 18C in the optical axis O direction. Can certainly be prevented.

21 to 26, a lens drive device 10D according to a fifth embodiment of the present invention will be described. Fig. 21 is a perspective view of the lens drive device according to the fifth embodiment of the present invention, viewed obliquely from the front and obliquely from above, and Fig. 22 shows an actuator base and an elastic member from the lens drive device shown in Fig. 16; It is a perspective view seen obliquely from the front and omits the electrode holder, and FIG. 23 is an exploded perspective view of the lens driving apparatus according to the fifth embodiment of the present invention as viewed obliquely from the front upward, and FIG. 24 is the lens driving apparatus shown in FIG. 25 is a side view of the lens driving device shown in FIG. 22, and FIG. 26 is a top view of the lens driving device shown in FIG. 22.

The lens drive device 10D of the fifth embodiment has the lens drive of the fourth embodiment shown in FIGS. 16 to 20 except that the configuration of the pressing step projection and the shape memory alloy for pressing is different as will be described later. It operates with the configuration similar to the apparatus 10C. Therefore, the same components as those of the lens driving apparatus 10C of the fourth embodiment are denoted by the same reference numerals, and their descriptions are omitted, and only the differences between the fourth and fifth embodiments will be described below. do.

First, the pressing step projections 188D-1 and 188D-2 which are the first of the differences between the fourth embodiment and the fifth embodiment will be described.

While the pressing step projections 188C-1a and 188C-1b in the lens drive device 10C according to the fourth embodiment are located above the step projections 184C-1, The pressing step projection 188D-1 in the lens drive device 10D is formed above the position shifted by 90 ° from the position of the step projection 184C-1 about the optical axis O. Similarly, the pressing step projections 188C-2a and 188C-2b in the lens drive device 10C according to the fourth embodiment are located above the step projections 184C-2, whereas the fifth embodiment The pressing step projection 188D-2 in the lens drive device 10D according to the present invention is formed above the position shifted 90 ° from the position of the step projection 184C-2 about the optical axis O. The pressing step projections 188D-1 and the pressing step projections 188D-2 are formed at positions shifted by 180 ° with respect to the optical axis O.

Next, the shape memory alloys 38D-1 and 38D-2 for pressurization which are the 2nd difference between 4th embodiment and 5th embodiment are demonstrated.

In the lens driving device 10C according to the fourth embodiment, the shape memory alloy 38C-1 for pressure is disposed above the shape memory alloy wire 32C-1, and the pressure step protrusions 188C-1a and 188C- are used. On the other hand, in the lens drive device 10D according to the fifth embodiment, the pressurized shape memory alloy 38D-1 is positioned at 90 ° from the position of the shape memory alloy wire 32C-1. It is arrange | positioned above and hangs on the pressing step protrusion 188D-1 mentioned above. Similarly, in the lens drive device 10C according to the fourth embodiment, the shape memory alloy 38C-2 for pressing is disposed above the shape memory alloy wire 32C-2, and the pressing step projections 188C-2a, 188C-2b), in the lens drive device 10D according to the fifth embodiment, the shape memory alloy 38D-2 for pressure is shifted by 90 ° from the position of the shape memory alloy wire 32C-2. It is arrange | positioned above the position, and hangs on the pressing step protrusion 188D-2 mentioned above. The pressurized shape memory alloy 38D-1 and the pressurized shape memory alloy 38D-2 are disposed at positions deviated by 180 degrees with respect to the optical axis O. One of the pair of alloy holding portions 382D-1 attached to both ends of the pressurized shape memory alloy 38C-1 is the first one of the two first electrode holder portions 144C positioned on the front side. While being fitted into and held in the alloy holding groove 144Ca formed in the holder portion 144C, the other of the pair of alloy holding portions 382D-1 has two first electrode holder portions 144C positioned at the rear side. Is fitted into and held in the alloy retaining groove 144Ca formed in one of the first electrode holder portions 144C. Similarly, one of the pair of alloy holding portions 382D-2 attached to both ends of the pressurized shape memory alloy 38C-2 is the first one of the two first electrode holder portions 144C located on the front side. Two first electrode holder portions positioned at the rear of the pair of alloy holding portions 382D-2 while being fitted and held in the alloy holding grooves 144Ca formed in the first electrode holder portion 144C. The fittings are held in the alloy holding grooves 144Ca formed in one of the first electrode holder portions 144C in the 144C.

The lens driving device 10D according to the fifth embodiment described above is used for the installation position and pressure of the shape memory alloy wires 32C-1 and 32C-2 as compared with the lens driving device 10C according to the fourth embodiment. Since the installation positions of the shape memory alloys 38D-1 and 38D-2 are separated from each other, the mounting operation of the lens drive device 10D can be easily achieved.

In addition, in this embodiment, the shape memory alloy wires 32C-1 and 32C-2 and the shape memory alloys 38D-1 and 38D-2 for press are arrange | positioned at the position which shifted by 90 degrees with respect to the optical axis O, respectively. However, this angle may be anything.

As mentioned above, although this invention was shown and demonstrated especially with reference to the embodiment, this invention is not limited to these embodiment. It is understood by those skilled in the art that various modifications can be made in form and detail without departing from the spirit and scope of the invention as defined in the claims. For example, in the present invention, the SMA assembly is not directly attached to the actuator base, but is attached to the actuator base via the electrode holder. Therefore, when the mechanism for adjusting the position of the electrode holder is used, the shape memory alloy member is attached to the housing. Even after the attachment, the amount of tension applied to the shape memory alloy member can be easily adjusted. As a result, it becomes possible to suppress the nonuniformity of a product characteristic. In addition, the guide means (elastic member) is not limited to the above-mentioned embodiment, You may use various things.

10, 10A, 10B, 10C, 10D... Lens driving device 11. Lens Barrel (Lens Assembly)
12... Housing 14, 14C... Actuator Base
142, 142C... Base portion 144... Base protrusion
146... Front recess 148... Anterior recess
144C.. First electrode holder portion 144Ca... Alloy retaining groove
146C.. Second electrode holder portion 16. Outer side cover
18, 18C... Lens holder 182, 182C... Tubular part
184, 184B-1, 184B-2, 184C-1, 184C-2... Protrusions (Steps)
186... Upper holder projection 186a... Upper holder protrusion
188C-1a, 188C-1b, 188C-2a, 188C-2b... Press step (protrusion)
20, 20C... Elastic member
22... Anterior support member (first support member; electrode holder)
222... Front base portion 224... Anterior support protrusion
224a.. . Anterior support protrusion 226... Front connection
226a... First projection 226b... Second projection
226c... Third protrusion
24, 24B... Rear support member (second support member)
242... Rear base portions 244, 244B... Posterior support protrusion
244a... Posterior support projections 246, 246B... Rear connection
26, 26C... Upper leaf spring 262... Upper ring
262a... Upper spring hole 264... Upper end
264a... Upper end hole 266... Upper arm
28, 28C... Lower leaf spring 282... Lower arc
284... Lower end 284a... Lower end hole
286... Lower arm 30... Inner upper cover (stopper)
302... Inner cover body 304... Step protrusion
304a... Through hole 306... Anterior extension
308... Rear extension
32, 32A, 32B-1, 32B-2, 32C-1, 32C-2... Shape memory alloy wire
32a, 32Aa, 32B-1a, 32B-2a, 32C-1a, 32C-2a... Middle section
34, 34B-1, 34B-2, 34C-1, 34C-2... Electrodes 342, 342B-1, 342B-2... Supported part
342a, 342B-2a... Circular hole 344... Connection
346... Terminal
36, 36A, 36B-1, 36B-2... SMA assembly
38C-1, 38C-2, 38D-1, 38D-2... Shape Memory Alloy for Pressurization
382C-1, 382C-2... Alloy holding part O... Optical axis of the lens
AFL… Auto focus lens

Claims (15)

A lens holder including a cylindrical portion for holding a lens barrel, a housing for supporting the lens holder so as to be movable only in the optical axis direction, moving means for moving the lens holder in the optical axis direction, and the lens holder in the optical axis A lens driving apparatus comprising a guide means for guiding to be movable only in a direction,
The moving means includes a shape memory alloy member sandwiched between the lens holder and the housing, and a pair of electrodes are attached to both ends of the shape memory alloy member for energizing it.
The housing includes an actuator base disposed on the lower side of the lens holder, and an electrode holder attached to the actuator base to hold the pair of electrodes. The lens driving apparatus according to claim 1, wherein the lens holder has a stepping protrusion projecting radially outward from the tubular portion to hang an intermediate portion of the shape memory alloy member. The optical guide according to claim 1 or 2, wherein the guide means comprises an elastic member disposed between the lens holder and the housing, the elastic member being positioned only in the optical axis direction with the lens holder positioned in the radial direction. A lens driving device, characterized in that the displaceable support. The lens drive according to any one of claims 1 to 3, wherein the elastic member is constituted by an upper leaf spring and a lower leaf spring respectively provided on the upper side and the lower side in the optical axis direction of the cylindrical portion of the lens holder. Device. 5. The upper side leaf spring of claim 4, wherein the upper leaf spring comprises: an upper ring portion attached to an upper end of the lens holder; four upper ends attached to the housing; and four upper sides connecting the upper ring portion and the four upper ends, respectively. A lens driving device having a dark portion. 6. The lower leaf spring according to claim 4 or 5, wherein the lower leaf spring comprises a pair of lower leaf springs, each of the lower leaf springs attached to a lower end of the lens holder, and the housing. And a pair of lower arm portions connecting the lower arc portion and the pair of lower end portions to be fixed to the lower end portion. The lens drive device according to any one of claims 1 to 6, wherein the shape memory alloy member is made of a shape memory alloy wire formed in a linear shape. The lens drive device according to any one of claims 1 to 6, wherein the shape memory alloy member is formed of a shape memory alloy member formed in a coil shape. The said step protrusion is arrange | positioned in multiple at the outer peripheral wall of a cylindrical part at equal angle intervals with respect to the said optical axis,
And the shape memory alloy member is arranged in the same number as the number of the step protrusions, and hangs on each step protrusion. A first step of attaching the upper leaf spring and the lower leaf spring to both ends in the optical axis direction of the lens holder having the cylindrical portion for holding the lens barrel;
A second step of attaching a support member to which the shape memory alloy assembly is attached to the lens holder;
A third step of attaching an actuator base to the support member in a state where the lower leaf spring is fitted from the bottom side of the lens holder;
A fourth step of attaching an inner upper cover to the support member in a state where the upper leaf spring is fitted from an upper side of the lens holder;
And a fifth step of covering the outer wound cover so as to cover the inner wound cover. 12. The shape memory alloy assembly according to claim 10, wherein the shape memory alloy assembly comprises a shape memory alloy member and a pair of electrodes electrically connected to both ends of the shape memory alloy member.
The lens holder has a first and a second side facing each other, and on the first side has a step protrusion projecting outward from the outer wall of the cylindrical portion,
The support member is composed of first and second support members provided to face each other, and the shape memory alloy assembly is attached to the first support member while the pair of electrodes are held.
The second step is
By hanging the intermediate portion of the shape memory alloy member to the step projection, the shape memory alloy member is interposed between the lens holder and the first support member, and the first support member is attached to the first side of the lens holder. Process to do,
And attaching the second support member to the second side of the lens holder. 12. The upper leaf spring of claim 11, wherein the upper leaf spring comprises an upper ring portion, four upper ends disposed at four corners and having upper spring holes, and four upper arm portions connecting the upper ring portion and the four upper ends. ,
The lower leaf spring is composed of a pair of lower leaf springs, each of the pair of lower leaf springs has a lower arc portion, a pair of lower ends having a lower end hole, and the lower arc portion and the pair. Consists of a pair of lower arm connecting the lower end of,
The first step is
Attaching the upper ring portion of the upper leaf spring to an upper end of the cylindrical portion of the lens holder;
And attaching the lower circular arc portion of the pair of lower leaf springs to the lower end of the cylindrical portion of the lens holder. 13. The apparatus of claim 12, wherein each of the first and second support members has a pair of support protrusions at both ends thereof, each of the pair of support protrusions having support protrusions at the top,
The second step includes a step of inserting the support protrusions of the first and second support members into upper end holes of the four upper ends of the upper leaf spring, respectively. . 14. The actuator base according to claim 13, wherein the actuator base has a ring-shaped base portion and four base protrusions projecting upward from four corners of the base portion, and the four base protrusions each projecting upwards. Take it,
The said 3rd process is the said actuator in the state which let four base protrusions formed in the said four base protrusions of the said actuator base pass through the lower end hole formed in the said pair of lower end of the pair of lower leaf springs, respectively. And attaching the four base protrusions of the base to the pair of support protrusions of the first and second support members, respectively. 15. The inner upper cover of claim 14, wherein the inner upper cover has a ring-shaped inner cover main body and four stepping protrusions projecting downward from four corners of the inner cover body, each of the four stepping protrusions having a through hole. have,
The fourth process includes forming the supporting protrusions of the first and second supporting members projecting through the upper end holes of the four upper ends of the upper leaf spring, respectively, on the four stepped protrusions of the inner upper cover. And the inner upper cover is attached to the first and second supporting members in a state of being inserted into the through hole.

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