Optical Drive Unit

Abstract

To provide a highly reliable optical drive unit.SOLUTION: An optical drive unit 1 includes: a movable part 2 capable of mounting an optical element; a drive part 3 for holding the movable part 2 so as to be capable of moving; and a fixing part 4 for holding the drive part 3. The fixing part 4 has a first fixing part 10, and a second fixing part 30 supported by the first fixing part 10, and the second fixing part 30 holds the drive part 3.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an optical driving device. [Background technology]

[0002] In recent years, various inventions have been proposed relating to optical driving devices that use a Smooth Impact Drive Mechanism (SIDM (registered trademark)) equipped with a piezoelectric element as an actuator.

[0003] For example, Patent Document 1 describes a lens driving device having a lens frame to which a lens can be attached, an actuator that movably holds the lens frame, and a base member that holds the actuator. The actuator is made up of a piezoelectric element, a drive shaft connected to one end of the piezoelectric element, and a weight connected to the other end of the actuator. In the lens driving device described in Patent Document 1, the weight is bonded to the base member, making it possible for the drive unit to be held by the base member.

[0004] However, in the lens driving device described in Patent Document 1, if an excessive load is applied to the piezoelectric element, the drive shaft, etc., there is a risk that these components may be damaged or otherwise malfunction, raising concerns that the reliability of the lens driving device may be reduced. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-13063 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical drive device with high reliability. [Means for solving the problem]

[0007] In order to achieve the above object, an optical driving device according to the present invention comprises: A movable part to which an optical element can be attached; A drive unit that movably holds the movable unit; A fixing portion that holds the driving portion, The fixing portion has a first fixing portion and a second fixing portion supported by the first fixing portion, The second fixing portion holds the driving portion.

[0008] In the optical driving device according to the present invention, the fixing part has a first fixing part and a second fixing part supported by the first fixing part, and the second fixing part holds the driving part. That is, the fixing part in the present invention is divided into two parts, the first fixing part and the second fixing part, and the second fixing part supported by the first fixing part can hold the driving part at a position different from the position where it should be held by the first fixing part. This realizes the holding of the driving part by the first fixing part and the second fixing part (however, the driving part may be held only by the second fixing part), and the driving part can be held firmly by the fixing part. Therefore, the resistance of the driving part to loads or external forces is increased, and defects such as damage or falling of the driving part can be effectively prevented, and a highly reliable optical driving device can be realized.

[0009] Furthermore, by dividing the fixed part into the first fixed part and the second fixed part, when assembling the drive part and the fixed part, it is possible to combine the first fixed part with the second fixed part, for example, in a state in which the drive part is combined with the second fixed part. In this case, it becomes possible to easily dispose the drive part inside the fixed part (between the first fixed part and the second fixed part), making it easy to assemble the drive part and the fixed part.

[0010] Preferably, the driving portion has a piezoelectric element and a shaft connected to one end of the piezoelectric element.

[0011] Preferably, the second fixing portion holds the other end of the shaft. With this configuration, the other end of the shaft is more resistant to loads or external forces, and the shaft can be effectively prevented from being damaged or otherwise impaired.

[0012] Preferably, the driving section has an inertia member connected to the other end of the piezoelectric element and applying an inertial force to the piezoelectric element, and the first fixed section holds the inertia member. With this configuration, the driving section can be held by the first fixed section and the second fixed section, so that the driving section can be firmly held by the fixed section, and defects such as damage to the driving section can be effectively prevented.

[0013] Preferably, the fixing portion further includes a third fixing portion supported by the first fixing portion or the second fixing portion, and the third fixing portion holds the driving portion. With this configuration, the driving portion can be held by at least the second fixing portion and the third fixing portion, so that the driving portion can be firmly held by the fixing portion, and defects such as damage to the driving portion can be effectively prevented.

[0014] Preferably, the third fixed part is supported by the first fixed part or the second fixed part via the shaft. In this case, the shaft serves as a pillar for supporting the third fixed part on the first fixed part or the second fixed part, and the third fixed part does not need to be provided with the pillar, so that the configuration of the third fixed part can be simplified. Furthermore, by adopting the above-mentioned configuration, the shaft functions as a part of the fixed part, and the third fixed part can be fixed to the first fixed part or the second fixed part via the shaft with sufficient strength.

[0015] Preferably, the other end of the shaft is adhered to the second fixed part, the one end of the shaft is adhered to the third fixed part, and the inertia member is adhered to the first fixed part. With this configuration, the driving unit can be held by adhesion at three different positions by each fixed part, so that the driving unit can be firmly held by the fixed parts, and defects such as damage to the driving unit can be effectively prevented.

[0016] Preferably, one of the first fixed part and the second fixed part is formed with a convex part for limiting the relative movement of the other, and the other is formed with a concave part corresponding to the convex part. By combining the first fixed part with the second fixed part in a state in which the convex part and the concave part are engaged with each other, it is possible to prevent the second fixed part from shifting in position or rotating relative to the first fixed part.

[0017] Preferably, the protrusion or the recess is located at a position spaced to one side from a holding position where the first fixing part holds the drive part. By adopting such a configuration, an engagement structure by the protrusion and the recess can be easily formed between the first fixing part and the second fixing part.

[0018] Preferably, a groove is formed on the surface of either the first fixing part or the second fixing part so as to surround the periphery of the convex part and prevent interference with the other. With this configuration, it is possible to prevent floating from occurring at the mating portion between the convex part and the concave part when the convex part and the concave part are engaged, and the second fixing part can be satisfactorily combined with the first fixing part.

[0019] Preferably, a gap is formed between the first fixing part and the second fixing part, and the gap is filled with resin. With this configuration, the first fixing part and the second fixing part can be firmly combined with each other via the resin. Furthermore, with the above configuration, when the first fixing part and the second fixing part are combined, it is possible to prevent floating from occurring at the joint between the first fixing part and the second fixing part, and the second fixing part can be well combined with the first fixing part. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic perspective view showing an optical driving device according to one embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the optical driving device shown in FIG. [Figure 3A] 3A is a perspective view of the optical element holding portion shown in FIG. 2. FIG. [Figure 3B] FIG. 3B is a perspective view of the optical element holding part shown in FIG. 3A rotated 180 degrees about the Z axis as a rotation axis. [Figure 4] FIG. 4 is a perspective view of the first fixing portion shown in FIG. [Diagram 5] 2. FIG. 5 is a perspective view of the second fixing portion shown in FIG. [Figure 6] 2. FIG. 6 is a perspective view of the third fixing portion shown in FIG. [Figure 7] 7 is a plan view of the optical driving device shown in FIG. 1 with a cover and a third fixing portion removed. [Figure 8A] FIG. 8A is a perspective view of the optical driving device shown in FIG. 1 with the cover removed. [Figure 8B] FIG. 8B is a partially transparent perspective view of the optical driving device shown in FIG. 8A. [Figure 8C] FIG. 8C is a partially transparent perspective view of the optical driving device shown in FIG. 8B rotated 180 degrees about the Z axis as a rotation axis. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0022] As shown in Fig. 1, an optical driving device 1 according to one embodiment of the present invention is mounted on a terminal device such as a mobile phone and enables driving by a SIDM (Smooth Impact Drive Mechanism (registered trademark)) actuator. The optical driving device 1 has an outer shape of a roughly rectangular prism, and as shown in Fig. 2, has a movable part 2, a driving part 3, and a fixed part 4. The fixed part 4 is divided into a first fixed part 10, a second fixed part 30, and a third fixed part 50, and the detailed structure thereof will be described later.

[0023] The driving section 3 is made of a piezoelectric actuator, and holds the movable section 2 (optical element holding section 60) so that it can move. The driving section 3 has a piezoelectric element 80, a first shaft 81, and an inertia member .

[0024] The driving unit 3 transmits the expansion and contraction of the piezoelectric element 80 to the first shaft 81, and moves the movable part 2, which is engaged with the first shaft 81 with a predetermined frictional force, by utilizing the difference in speed between when the piezoelectric element 80 expands and when it contracts. The direction of movement (movement direction) of the movable part 2 is the Z-axis direction, which corresponds to the axial direction of the first shaft 81. When a lens is provided as the optical element in the optical element holding unit 60, the direction of movement of the movable part 2 is the optical axis direction of the lens.

[0025] The piezoelectric element 80 has a rectangular column shape, and inside the piezoelectric element 80, a plurality of dielectric layers and internal electrode layers are alternately laminated in the Z-axis direction. The piezoelectric element 80 is disposed on the second fixed part 30. External electrodes (not shown) are formed on the opposing side surfaces of the piezoelectric element 80, and the internal electrode layers are electrically connected to the external electrodes. One end of each of a pair of lead frames 101a, 101b is fixed to each external electrode, and the other end of each of the pair of lead frames 101a, 101b is connected to the circuit board 100 (FIG. 8A). An electric signal (rectangular wave) is applied from the circuit board 100 to the piezoelectric element 80 via the lead frames 101a, 101b, thereby enabling the piezoelectric element 80 to expand and contract in the Z-axis direction. The circuit board 100 is made of an FPC (Flexible Printed Circuits).

[0026] A first shaft 81 is connected to the upper end of the piezoelectric element 80. The method of fixing the first shaft 81 and the piezoelectric element 80 is not particularly limited, but for example, they can be bonded with resin. The material of the first shaft 81 is not particularly limited, but for example, metal, carbon, or resin can be used. This point is the same for the second shaft 85 described later. The first shaft 81 is columnar and moves back and forth by the expansion and contraction of the piezoelectric element 80. The first shaft 81 slidably holds the movable part 2, and its lower end is fixed to the second fixed part 30 and its upper end is fixed to the third fixed part 50. The diameter (diameter) of the first shaft 81 is larger than the diameter (diameter) of the second shaft 85. In addition, the cross-sectional area of ​​the first shaft 81 cut in a direction perpendicular to the longitudinal direction is larger than the cross-sectional area of ​​the second shaft 85 cut in the same direction.

[0027] The optical element holding part 60 constituting the movable part 2 is frictionally engaged with the outer circumferential surface of the first shaft 81. The diameter (diameter) of the first shaft 81 is larger than the diameter (length of one side or length of the long side) of the piezoelectric element 80, and the surface area of ​​the end face of the first shaft 81 is larger than the surface area of ​​the end face of the piezoelectric element 80. In the illustrated example, the shape of the first shaft 81 is cylindrical, but the shape is not particularly limited and may be polygonal.

[0028] The inertia member 82 is formed in a rectangular column shape and is connected to the lower end of the piezoelectric element 80. The inertia member 82 is disposed on the first fixed part 10, and the position of the connection part between the piezoelectric element 80 and the inertia member 82 is approximately the same as the position of the boundary part between the first fixed part 10 and the second fixed part 30. The inertia member 82 has a function as an inertia body for applying an inertial force to the first shaft 81, and is for generating a displacement due to the expansion and contraction of the piezoelectric element 80 only on the first shaft 81 side. The inertia member 82 is, for example, a weight, and is made of a material having a higher specific gravity than the piezoelectric element 80 and the first shaft 81. The material of the inertia member 82 is not particularly limited, but for example, a metal having a high specific gravity such as tungsten or an alloy containing such a metal can be adopted. The method of fixing the inertia member 82 and the piezoelectric element 80 is not particularly limited, but for example, the two can be bonded with a resin.

[0029] The second shaft 85 is columnar and slidably supports the movable part 2. The lower end of the second shaft 85 is fixed to the first fixed part 10, and the upper end of the second shaft 85 is fixed to the third fixed part 50. Note that the optical driving device 1 in this embodiment is provided with the first shaft 81 and the second shaft 85, but the second shaft 85 is configured separately from the driving part 3 and mainly functions as the fixed part 4. In addition, the second shaft 85 plays a role in regulating the rotation of the movable part 3 (optical element holding part 60) as described later.

[0030] The movable part 2 is made of an optical element holding part 60, and is configured so that an optical element (not shown) such as an optical lens, an optical prism, or a reflecting mirror can be attached. As shown in FIG. 3A, the optical element holding part 60 has a main body part 61. The main body part 61 is cylindrical, and an element installation opening part 62 is formed in the center part. An optical element can be provided on the inner surface of the element installation opening part 62. In the following, for convenience of explanation, the four corner parts of the main body part 61 are called a first corner part 61a to a fourth corner part 61d, respectively.

[0031] A magnetic body installation step 63 is formed at a first corner 61a of the main body 61. The magnetic body installation step 63 is formed with a predetermined length from the upper surface of the main body 61 along the Z-axis direction. The sensor magnet 103 shown in FIG. 2 can be installed on the step surface of the magnetic body installation step 63 in the manner shown in FIG. 7. The sensor magnet 103 is adhesively fixed to the magnetic body installation step 63 by, for example, an adhesive. The X-axis direction width and the Y-axis direction width of the magnetic body installation step 63 are approximately equal to the X-axis direction width and the Y-axis direction width of the sensor magnet 103, respectively, and the step height of the magnetic body installation step 63 is higher than the height of the sensor magnet 103.

[0032] Here, the sensor magnet 103 will be described. As shown in Fig. 7, the sensor magnet 103 is disposed facing the position sensor 102 fixed to the circuit board 100 in the X-axis direction. The position sensor 102 is disposed to detect the magnetic field emitted from the sensor magnet 103.

[0033] When the optical element holding part 60 moves back and forth along the Z-axis direction, the position of the sensor magnet 103 in the Z-axis direction is displaced accordingly. At this time, the strength of the magnetic field detected by the position sensor 102 changes according to the position of the sensor magnet 103 in the Z-axis direction. Therefore, by analyzing the change in the strength of the magnetic field emitted from the sensor magnet 103, it is possible to detect the position of the sensor magnet 103 in the Z-axis direction, i.e., the position of the optical element holding part 60 in the Z-axis direction. Note that a noise canceling capacitor 104 is provided on the circuit board 100 at a position adjacent to the position sensor 102.

[0034] 3A, a substrate-facing step surface 71 is formed at a first corner 61a of the main body 61. The substrate-facing step surface 71 has a step shape and is formed to span a side portion located between the first corner 61a and the second corner 61b of the main body 61 and a side portion located between the first corner 61a and the fourth corner 61d. The substrate-facing step surface 71 is formed to prevent contact between the side portions of the main body 61 and the circuit board 100, and is disposed opposite the circuit board 100 as shown in FIG.

[0035] As shown in FIG. 3A, stoppers 70a, 70b are formed at the second corner 61b of the main body 61. The stopper 70a is formed so as to straddle a side portion located between the first corner 61a and the second corner 61b of the main body 61 and a side portion located between the second corner 61b and the third corner 61c. The stopper 70a protrudes upward from the upper surface of the main body 61 and forms a step with respect to its periphery. The stopper 70a is for restricting the upward movement of the optical element holding part 60, and the optical element holding part 60 can move upward until the stopper 70a abuts against the lower surface of the third fixing part 50 (or to a position just before that) (see FIG. 8A).

[0036] Similarly, the protrusion 70b is formed to straddle a side portion located between the first corner 61a and the second corner 61b of the main body 61 and a side portion located between the second corner 61b and the third corner 61c. The protrusion 70b protrudes downward from the lower surface of the main body 61 and forms a step with respect to its surroundings. The stopper 70b is for restricting the downward movement of the optical element holding part 60, and the optical element holding part 60 is allowed to move downward until the stopper 70b abuts on the upper surface of the second fixing part 30 (or to a position just before that) (see FIG. 8A).

[0037] A shaft sliding groove 64 is formed in the second corner 61b of the main body 61. The shaft sliding groove 64 is formed from the upper surface to the lower surface of the main body 61, and is recessed toward the center of the main body 61. As shown in FIG. 7, the shaft sliding groove 64 has a shape that is bent substantially vertically when viewed from above. An engagement portion 106 can be disposed inside the shaft sliding groove 64. The engagement portion 106 will be described in detail later.

[0038] 3A, a pedestal 65 is formed at the lower end of the shaft sliding groove portion 64. The pedestal 65 has a predetermined length in the Z-axis direction, and its lower surface is flush with the lower surface of the main body portion 61. The engagement portion 106 can be placed on the pedestal 65.

[0039] The engaging portion 106 is made of an elastic member and has a predetermined length in the Z-axis direction. As shown in FIG. 7, the engaging portion 106 is bent in a substantially L-shape when viewed from above. The engaging portion 106 is formed by bending a flat metal plate material at approximately 90 degrees by machining. The shape of the engaging portion 106 corresponds to the groove shape of the shaft sliding groove 64, and the engaging portion 106 can be engaged inside the shaft sliding groove 64. There is no particular limitation on the method of fixing the engaging portion 106 and the shaft sliding groove 64, but for example, they can be adhesively fixed with a resin or the like. The engaging portion 106 abuts against the outer circumferential surface of the first shaft 81, and the first shaft 81 is sandwiched between a portion on one side and a portion on the other side of the bent portion.

[0040] 2 and 7, the pressing member 105 is made of an elastic member, such as a leaf spring. One end of the pressing member 105 is fixed to a pressing member installation hole 66 (described later) with, for example, an epoxy resin, and the other end abuts on the outer circumferential surface of the first shaft 81. A portion of the pressing member 105 is bent, which allows the pressing member 105 to be disposed along the side of the main body 61 from the second corner 61b to the third corner 61c of the main body 61. The pressing member 105 presses the outer circumferential surface of the first shaft 81 with the other end by elastic force.

[0041] When viewed from above, the engaging portion 106 and the pressing member 105 come into contact with the outer circumferential surface of the first shaft 81 at three points, and the first shaft 81 is sandwiched between these members. At this time, a frictional force according to the pressing force of the pressing member 105 acts on the contact points between the first shaft 81 and each of the pressing member 105 and the engaging portion 106. This makes it possible to frictionally engage the optical element holding portion 60 with the first shaft 81 via the engaging portion 106 and the pressing member 105, and a configuration is obtained in which the movable portion 2 (optical element holding portion 60) is held by the driving portion 3 (first shaft 81). In this way, the first shaft 81 holds (supports) the optical element holding portion 60 at the position where it is sandwiched between the pressing member 105 and the engaging portion 106.

[0042] As shown in Fig. 3A and Fig. 7, a pressing member installation hole 66 is formed in the third corner 61c of the main body 61. The pressing member installation hole 66 is formed to penetrate a side portion located between the second corner 61b and the third corner 61c of the main body 61 and a side portion located between the third corner 61c and the fourth corner 61d. The width of the pressing member installation hole 66 in the Z-axis direction is approximately equal to or larger than the width of the pressing member 105 in the Z-axis direction, and the other end of the pressing member 105 is inserted therein. This makes it possible to fix the pressing member 105 to the optical element holding part 60.

[0043] A T-shaped notch 67 is formed in the third corner 61c of the main body 61. The T-shaped notch 67 has a T shape when viewed from above, and extends downward from the upper surface of the main body 61. The inside of the T-shaped notch 67 is connected to the pressing member installation hole 66. When fixing the pressing member 105 to the pressing member installation hole 66, it is possible to inject resin from the T-shaped notch 67 and adhesively fix the pressing member 105 to the pressing member installation hole 66 with the resin.

[0044] As shown in Fig. 3B and Fig. 7, a shaft fixing surface 68 is formed at the fourth corner 61d of the main body 61. The shaft fixing surface 68 is formed from the top surface to the bottom surface of the main body 61, and a pair of shaft fixing protrusions 69, 69 is formed at approximately the center in the Z-axis direction. The shaft fixing protrusions 69, 69 are fixed to the second shaft 85 and serve to regulate the rotation of the movable part 2. The shaft fixing protrusions 69, 69 protrude by a predetermined length in a direction approximately perpendicular to the shaft fixing surface 68. The protruding length of the shaft fixing protrusions 69, 69 is approximately equal to the diameter (diameter) of the second shaft 85.

[0045] A pair of contact protrusions 69a, 69a is formed on each of the opposing surfaces of the shaft fixing protrusions 69, 69. The contact protrusions 69a, 69a protrude in a direction approaching each other. The contact protrusions 69a, 69a extend a predetermined length in a direction substantially perpendicular to the shaft fixing surface 68. The interval between the contact protrusions 69a, 69a is substantially equal to the diameter of the second shaft 85. By disposing the second shaft 85 between the contact protrusions 69a, 69a, the second shaft 85 can be engaged with the contact protrusions 69a, 69a with a predetermined frictional force, and the optical element holder 60 can be slidably fixed to the second shaft 85. The second shaft 85 restricts the rotation of the optical element holder 60 at the positions of the shaft fixing protrusions 69, 69 (contact protrusions 69a, 69a).

[0046] As shown in Figures 8B and 8C, when comparing the length L1 of the holding area 111 of the movable part 2 held by the first shaft 81 (in other words, the length in the Z-axis direction of the pressing member 105) with the length L2 of the support area 112 of the movable part 2 supported by the second shaft 85 (in other words, the length in the Z-axis direction of the shaft fixing protrusions 69, 69), the length L1 is greater than the length L2.

[0047] When the optical driving device 1 is viewed from the side, the support region 112 is disposed inside both ends of the holding region 111. In other words, the upper end of the support region 112 is disposed below the upper end of the holding region 111, and the lower end of the support region 112 is disposed above the lower end of the holding region 111.

[0048] As shown in FIG. 2, the fixed portion 4 in this embodiment has a first fixed portion 10, a second fixed portion 30, and a third fixed portion 50, which hold the drive portion 3. The fixed portion 4 is made of a resin such as LCP (liquid crystal polymer). The first fixed portion 10 and the second fixed portion 30 form the lower portion of the fixed portion 4 (corresponding to the base member in the prior art), and the third fixed portion 50 mainly forms the upper portion of the fixed portion 4. The lower portion of the fixed portion 4 in this embodiment is divided into two portions, the first fixed portion 10 and the second fixed portion 30.

[0049] As shown in Fig. 4, the first fixing portion 10 has a first base portion 11. The first base portion 11 has a generally flat plate shape, and a first opening 12 is formed in a generally central portion thereof. The first opening 12 is formed at a position corresponding to the element installation opening 62 formed in the optical element holding portion 60 described above. For ease of explanation, the four corners of the first base portion 11 will be referred to as a first corner 11a to a fourth corner 11d, respectively, below.

[0050] A first lateral recess 15 is formed on a side portion located between the first corner 11a and the second corner 11b of the first base portion 11. The first lateral recess 15 is formed from one end to the other end of the first base portion 11 in the X-axis direction, and has a predetermined depth in the Y-axis direction. The depth of the first lateral recess 15 in the Y-axis direction is approximately equal to the thickness of the circuit board 100 shown in FIG. 2, and a part of the circuit board 100 is disposed in the first lateral recess 15.

[0051] A stepped corner 16 is formed at the second corner 11b. The stepped corner 16 is formed so as to straddle a side portion located between the first corner 11a and the second corner 11b of the first base portion 11 and a side portion located between the second corner 11b and the third corner 11c. The stepped surface of the stepped corner 16 has a substantially triangular shape when viewed from above, and is formed a predetermined depth below the upper surface of the first base portion 11.

[0052] A fixing recess 17 is formed in the step corner 16. The fixing recess 17 has a substantially rectangular shape when viewed from above, and the shape corresponds to the bottom shape of the inertia member 82 shown in FIG. 2. As shown in FIG. 8B, the fixing recess 17 has a predetermined depth, and the inertia member 82 can be placed therein. By accommodating the inertia member 82 in the fixing recess 17, the inertia member 82 can be held (fixed) in the fixing recess 17. That is, the fixing recess 17 functions as a first holding portion 21 for holding the inertia member 82. The inertia member 82 is bonded to the fixing recess 17 by a resin. By filling the fixing recess 17 with the resin, the inertia member 82 can be firmly held in the fixing recess 17 by the adhesive force.

[0053] In this way, by disposing the inertia member 82 inside the fixing recess 17 and further adhesively fixing it with resin, it becomes possible for the first holding part 21 to firmly hold the inertia member 82 located at the lower end part of the drive part 3. The resin for fixing the inertia member 82 to the first holding part 21 is preferably a silicone-based resin. By using a silicone-based resin, it becomes possible for the resin to absorb vibrations of the drive part 3 and external shocks, and the first holding part 21 can hold a part of the drive part 3 in a stable state.

[0054] As shown in Fig. 4, a narrow step portion 14 is formed at the third corner portion 11c of the first base portion 11. The narrow step portion 14 is formed at a corner portion where an upper surface of the first base portion 11 intersects with a side surface (a side surface located between the second corner portion 11b and the third corner portion 11c). A narrow fixing piece 54a (Fig. 6) of the third fixing portion 50, which will be described later, is fixed to the narrow step portion 14 by adhesion.

[0055] A limiting protrusion 19 is formed at a position close to the step width narrow portion 14. The limiting protrusion 19 is formed in a substantially cylindrical shape and protrudes upward from the upper surface of the first base portion 11. A tapered surface is formed at the end of the limiting protrusion 19. The limiting protrusion 19 is configured to be engageable with a limiting recess 44 (FIG. 5) formed on the bottom surface of the second fixed portion 30 described later, and by engaging the limiting protrusion 19 with the limiting recess 44, it is possible to prevent relative movement and rotation between the first fixed portion 10 and the second fixed portion 30. As shown in FIG. 8B, the limiting protrusion 19 is located at a position spaced upward from the position (first holding portion 21) where the first fixed portion 10 (fixing recess 17) holds the inertia member 82.

[0056] 4, a ring-shaped groove 20 is formed on the upper surface of the first base portion 11 so as to surround the periphery of the limiting protrusion 19. The ring-shaped groove 20 is intended to prevent the upper surface of the first fixed portion 10 from interfering with the bottom surface of the second fixed portion 30 when the first fixed portion 10 and the second fixed portion 30 are combined. In other words, by forming the ring-shaped groove 20 around the limiting protrusion 19, it is possible to prevent rattling at the joint between the upper surface of the first base portion 11 and the bottom surface of the second base portion 31 due to burrs around the limiting protrusion 19.

[0057] A first small diameter hole 18 is formed in the fourth corner 11d of the first base portion 11. The first small diameter hole 18 is a through hole, and the second shaft 85 shown in FIG. 2 can be inserted therein. The first small diameter hole 18 has a circular shape when viewed from above, and the diameter of the first small diameter hole 18 is approximately equal to or larger than the diameter of the second shaft 85. By inserting the lower end of the second shaft 85 into the first small diameter hole 18, the lower end of the second shaft 85 is held (supported) by the first small diameter hole 18. That is, as shown in FIG. 8B, the first small diameter hole 18 functions as a fourth holding portion 22 for holding the lower end of the second shaft 85. The lower end of the second shaft 85 is bonded to the first small diameter hole 18 by resin.

[0058] In this way, by placing the lower end of the second shaft 85 inside the first small diameter hole 18 and further adhesively fixing it with resin, it is possible for the lower end of the second shaft 85 to be firmly held by the fourth retaining portion 22.

[0059] The resin for fixing the lower end of the second shaft 85 to the fourth holding part 22 is preferably an epoxy resin. Since the second shaft 85 functions as a pillar connecting the first fixed part 10 and the third fixed part 50, by fixing the lower end of the second shaft 85 to the first fixed part 10 using an epoxy resin, the lower end of the second shaft 85 is fixed to the first fixed part 10 with sufficient adhesive strength, and it becomes possible to sufficiently ensure the structural strength of the fixed part 4. Furthermore, since the second shaft 85 is held in a stable state relative to the first fixed part 10, it becomes possible for the second shaft 85 to support the optical element holding part 60 in a stable state.

[0060] As shown in Fig. 4, a wide step portion 13 is formed between the first corner portion 11a and the fourth corner portion 11d. The wide step portion 13 is formed at a corner portion where an upper surface of the first base portion 11 intersects with a side surface (a side surface located between the first corner portion 11a and the fourth corner portion 11d). The width in the Y-axis direction of the wide step portion 13 is wider than the width in the Y-axis direction of the narrow step portion 14. A wide fixing piece 53a (Fig. 6) of the third fixing portion 50 is fixed to the wide step portion 13 by adhesion.

[0061] As shown in FIG. 8A, the second fixed part 30 is supported by the first fixed part 10 and is disposed (placed) above the first fixed part 10. As shown in FIG. 5, the second fixed part 30 has a second base part 31. The second base part 31 has a substantially flat plate shape, and a second opening part 32 is formed in a substantially central part thereof. The second opening part 32 is formed at a position corresponding to the first opening part 12 of the first fixed part 10. In the following, for ease of explanation, the four corner parts of the second base part 31 are referred to as a first corner part 31a to a fourth corner part 31d, respectively.

[0062] A second lateral recess 35 is formed at the first corner 31a of the second base portion 31. The second lateral recess 35 is formed at a side portion located between the first corner 31a and the second corner 31b of the second base portion 31, and has a predetermined depth in the Y-axis direction. The bottom surface of the second lateral recess 35 is substantially flush with the bottom surface of the first lateral recess 15 of the first fixing portion 10 shown in FIG. 4, and it is possible to arrange a part of the circuit board 100 shown in FIG. 2 so as to straddle the first lateral recess 15 and the second lateral recess 35.

[0063] A long protrusion 36 and a short protrusion 37 are formed at the second corner 32a of the second base portion 31. The long protrusion 36 and the short protrusion 37 are arranged to be perpendicular to each other, and are arranged inside the stepped corner 16 of the first fixing portion 10 as shown in FIG. 8A. As shown in FIG. 5, the long protrusion 36 is formed at a side portion located between the second corner 31b and the third corner 31c of the second base portion 31, and the short protrusion 37 is formed at a side portion located between the first corner 31a and the second corner 31b of the second base portion 31. The long protrusion 36 extends along the Y-axis direction and has a predetermined thickness in the X-axis direction. The short protrusion 37 extends along the X-axis direction and has a predetermined thickness in the Y-axis direction. The downward protruding length of the long protruding portion 36 is greater than the downward protruding length of the short protruding portion 37, and a step is formed between the bottom surface of the long protruding portion 36 and the bottom surface of the short protruding portion 37.

[0064] A protruding columnar portion 38 is formed on the bottom surface of the short protruding portion 37. The protruding columnar portion 38 is formed at a position spaced a predetermined distance from the long protruding portion 36, and protrudes downward. The length of the downward protrusion of the protruding columnar portion 38 is equal to the step width between the bottom surface of the long protruding portion 36 and the bottom surface of the short protruding portion 37.

[0065] A frame insertion passage 39a is formed on one side in the X-axis direction of the protruding columnar portion 38. The frame insertion passage 39a is a space formed between the protruding columnar portion 38 and the long protruding portion 36, and the lead frame 101a shown in Fig. 2 can be drawn out toward the circuit board 100 along the periphery of the protruding columnar portion 38 through the frame insertion passage 39a (Fig. 8A).

[0066] A frame insertion passage 39b is formed on the opposite side of the frame insertion passage 39a across the protruding columnar portion 38. The frame insertion passage 39b is formed of a space similar to the frame insertion passage 39a, and the lead frame 101b shown in Fig. 2 can be drawn through the frame insertion passage 39b toward the circuit board 100 along the periphery of the protruding columnar portion 38 (Fig. 8A). By drawing the lead frame 101a from one side across the protruding columnar portion 38 and drawing the lead frame 101b from the other side, it is possible to achieve good insulation between the lead frames 101a and 101b.

[0067] A second large diameter hole 42 is formed in the second corner portion 31b of the second base portion 31. The second large diameter hole 42 is a through hole that passes through the second base portion 31 in the Z-axis direction. The second large diameter hole 42 allows the first shaft 81 to be inserted therethrough.

[0068] The second large diameter hole 42 has a circular shape when viewed from above, and the diameter of the second large diameter hole 42 is approximately equal to or larger than the diameter of the first shaft 81. As shown in FIG. 8B, the lower end of the first shaft 81 is disposed (inserted) inside the second large diameter hole 42, and the lower end of the first shaft 81 is held (fixed) inside the second large diameter hole 42. That is, the second large diameter hole 42 functions as a second holding portion 45 for holding the lower end of the first shaft 81. In this way, in this embodiment, a configuration is provided in which the second fixing portion 30 holds a part of the driving portion 3.

[0069] The lower end of the first shaft 81 is bonded to the second large diameter hole 42 by resin. By filling the inside of the second large diameter hole 42 with resin, it becomes possible to firmly hold the lower end of the first shaft 81 inside the second large diameter hole 42 by the adhesive force of the resin.

[0070] In this way, the first shaft 81 is disposed inside the second large diameter hole 42, and is further adhesively fixed with resin, so that the second holding part 45 can firmly hold the lower end of the first shaft 81 located below the driving part 3. The resin for fixing the lower end of the first shaft 81 to the second holding part 45 is preferably a silicone-based resin. By using a silicone-based resin, it becomes possible for the resin to absorb vibrations of the driving part 3 and shocks from the outside, so that the second holding part 45 can hold a part of the driving part 3 in a stable state. As described above, in this embodiment, the first fixing part 10 holds the driving part 3 by the first holding part 21 (fixing recess 17), and the second fixing part 30 holds the driving part 3 by the second holding part 45 (second large diameter hole 42).

[0071] As shown in Fig. 5, a contact fixing portion 41 is formed between the second corner portion 31b and the third corner portion 31c of the second base portion 31. As shown in Fig. 8A, the contact fixing portion 41 constitutes a part of the bottom surface of the second base portion 31, and abuts against the upper surface of the first base portion 11 of the first fixing portion 10, and is fixed (supported) thereto. Note that the bottom surface of the second base portion 31 also constitutes an abutment surface with the upper surface of the first base portion 11 in a portion other than the contact fixing portion 41, but in this embodiment, the abutment surface formed adjacent to the long protruding portion 36 in the Y-axis direction is specifically referred to as the contact fixing portion 41.

[0072] When the contact fixing portion 41 and the upper surface of the first base portion 11 are in contact with each other, a gap is formed between the upper surface of the first fixing portion 10 and the bottom surface of the second fixing portion 30. In particular, a resin-filled space 40 is formed between the bottom surface of the long protruding portion 36 and the upper surface of the first base portion 11 as the gap. The resin-filled space 40 is filled with, for example, an epoxy resin, and the upper surface of the first base portion 11 and the bottom surface of the long protruding portion 36 can be firmly fixed together via the resin. A similar gap is also formed between the bottom surface of the protruding columnar portion 38 and the upper surface of the first base portion 11.

[0073] As shown in FIG. 5, a concave narrow portion 34 is formed in the third corner 31c of the second base portion 31. The concave narrow portion 34 is formed in a side portion located between the second corner 31b and the third corner 31c, and has a predetermined depth in the X-axis direction. The bottom surface of the concave narrow portion 34 is disposed substantially flush with the bottom surface of the concave narrow portion 14 of the first fixing portion 10 shown in FIG. 4, and the narrow fixing piece 54a (FIG. 6) of the third fixing portion 50 is fixed by adhesion so as to straddle the concave narrow portion 34 and the narrow step portion 14. Note that curved recesses are formed on both sides of the bottom surface of the concave narrow portion 34 in the Y-axis direction, and by forming such recesses, resin is filled inside the recesses, making it possible to increase the adhesion between the concave narrow portion 34 and the narrow step portion 14 and the narrow fixing piece 54a.

[0074] A limiting recess 44 is formed at a position adjacent to the recessed narrow width portion 34. The limiting recess 44 is formed on the bottom surface of the second base portion 31, and is formed at a position corresponding to the limiting protrusion 19 of the first fixed portion 10. The limiting recess 44 has a shape corresponding to the limiting protrusion 19, and is formed to be able to engage with the limiting protrusion 19.

[0075] A second small diameter hole 43 is formed in the fourth corner 31d of the second base portion 31. The second small diameter hole 43 is a through hole that penetrates the second base portion 31 in the Z-axis direction. The second small diameter hole 43 is disposed diagonally with respect to the second large diameter hole 42, sandwiching the second opening 32. The second small diameter hole 43 has a circular shape when viewed from above, and as shown in Figs. 8B and 8C, the second shaft 85 can be inserted into the second small diameter hole 43. The diameter (diameter) of the second small diameter hole 43 is approximately equal to or larger than the diameter of the second shaft 85, and is smaller than the diameter of the second large diameter hole 42.

[0076] In the second small diameter hole 43, the second shaft 85 simply passes through it, and the inserted portion is not fixed with resin or the like to the inside of the second small diameter hole 43. Since the diameter of the second small diameter hole 43 is approximately equal to the diameter of the second shaft 85, when the second shaft 85 is inserted into the second small diameter hole 43, the inserted portion is held by the second small diameter hole 43.

[0077] As shown in Fig. 5, a wide recessed portion 33 is formed on a side portion located between the first corner portion 31a and the fourth corner portion 31d of the second base portion 31. As shown in Fig. 8C, the width in the Y-axis direction of the wide recessed portion 33 is substantially equal to the width in the Y-axis direction of the wide stepped portion 13 of the first fixed portion 10, and the bottom surface of the recess of the wide recessed portion 33 and the bottom surface of the wide stepped portion 13 are substantially flush with each other. When the first fixed portion 10 and the second fixed portion 30 are combined, the wide fixed piece 53a (Fig. 6) of the third fixed portion 50 is fixed by adhesion so as to straddle the wide recessed portion 33 and the wide stepped portion 13.

[0078] 6, the third fixed part 50 has a top plate part 51. The top plate part 51 has a generally flat plate shape, and a third opening part 52 is formed in the generally central part. The third opening part 52 is formed in a position corresponding to the first opening part 12 of the first fixed part 10 and the second opening part 32 of the second fixed part 30. For ease of explanation, the four corners of the top plate part 51 will be referred to as a first corner part 51a to a fourth corner part 51d, respectively, below.

[0079] A third large diameter hole 55 is formed in the second corner portion 51b of the top plate portion 51. The third large diameter hole 55 is a through hole that passes through the top plate portion 51 in the Z-axis direction. The third large diameter hole 55 allows the first shaft 81 to be inserted therethrough.

[0080] The third large diameter hole 55 has a circular shape when viewed from above, and the diameter of the third large diameter hole 55 is approximately equal to or larger than the diameter of the first shaft 81. As shown in FIG. 8B , the upper end of the first shaft 81 is placed (inserted) inside the third large diameter hole 55, and the upper end of the first shaft 81 is held (fixed) inside the third large diameter hole 55. In other words, the third large diameter hole 55 functions as a third holding portion 58 for holding the upper end of the first shaft 81. In this way, in this embodiment, the third fixing portion 50 A configuration is obtained in which the third fixed portion 50 holds a part of the drive portion 3, and further a configuration is obtained in which the third fixed portion 50 is supported by the first fixed portion 10 and the second fixed portion 30 via the first shaft 81.

[0081] The upper end of the first shaft 81 is bonded to the third large diameter hole 55 by resin. By filling the inside of the third large diameter hole 55 with resin, it becomes possible to firmly hold the upper end of the first shaft 81 inside the third large diameter hole 55 by the adhesive force of the resin.

[0082] In this way, the first shaft 81 is disposed inside the third large diameter hole 55, and is further adhesively fixed with resin, so that the upper end portion of the first shaft 81 located above the driving unit 3 can be firmly held by the third holding part 58. The resin for fixing the upper end portion of the first shaft 81 to the third holding part 58 is preferably a silicone-based resin. By using a silicone-based resin, it becomes possible for the resin to absorb vibrations of the driving unit 3 and shocks from the outside, so that it becomes possible for the third holding part 58 to hold a part of the driving unit 3 in a stable state. In addition, it becomes possible to prevent defects in the joint between the upper end portion of the first shaft 81 and the third large diameter hole 55 that may occur due to thermal contraction (linear expansion) of the first shaft 81.

[0083] Here, the distance between the position where the upper end of the first shaft 81 is fixed inside the third large diameter hole 55 of the third fixing part 50 and the position where the lower end of the first shaft 81 is fixed inside the second large diameter hole 42 of the second fixing part 30 (the distance between the fixing positions of the fixing part 4 where the upper end and the lower end of the first shaft 81 are fixed, or the distance between the second holding part 45 and the third holding part 58) is defined as L3. Also, the distance between the position where the upper end of the second shaft 85 is fixed inside the third small diameter hole 56 of the third fixing part 50 and the position where the lower end of the second shaft 85 is fixed inside the first small diameter hole 18 of the first fixing part 10 (the distance between the fixing positions of the fixing part 4 where the ends of the second shaft 85 are fixed, or the distance between the fourth holding part 22 and the fifth holding part 59) is defined as L4. In this embodiment, the distance L3 is smaller than the distance L4.

[0084] As shown in FIG. 6, a narrow protrusion 54 is formed at the third corner 51c of the top plate 51. The narrow protrusion 54 is formed at a side portion located between the second corner 51b and the third corner 51c of the top plate 51. The narrow protrusion 54 has a surface parallel to the YZ plane and protrudes downward. As shown in FIG. 8A, when the third fixing part 50 is combined with the first fixing part 10 and the second fixing part 30, the narrow protrusion 54 connects the top plate 51 and the second fixing part 30.

[0085] A narrow fixing piece 54a is formed at the lower end of the narrow protruding portion 54. The Y-axis direction width of the narrow fixing piece 54a is smaller than the Y-axis direction width of the narrow protruding portion 54, and is approximately equal to the Y-axis direction width of each of the stepped narrow portion 14 of the first fixing portion 10 and the concave narrow portion 34 of the second fixing portion 30, as shown in Fig. 8A. The narrow fixing piece 54a is disposed so as to straddle the stepped narrow portion 14 and the concave narrow portion 34 connected in the Z-axis direction, and is adhesively fixed thereto with resin.

[0086] As shown in FIG. 6, a third small diameter hole 56 is formed in the fourth corner 51d of the top plate 51. The third small diameter hole 56 is a through hole that penetrates the top plate 51 in the Z-axis direction. The third small diameter hole 56 is disposed diagonally with respect to the third large diameter hole 55, sandwiching the third opening 52. The third small diameter hole 56 has a circular shape when viewed from above, and as shown in FIG. 8B and FIG. 8C, the second shaft 85 can be inserted into the third small diameter hole 56. The diameter (diameter) of the third small diameter hole 56 is approximately equal to or larger than the diameter of the second shaft 85, and is smaller than the diameter of the third large diameter hole 55.

[0087] The upper end of the second shaft 85 is disposed (inserted) inside the third small diameter hole 56, and the upper end of the second shaft 85 is held (fixed) inside the third small diameter hole 56. In other words, the third small diameter hole 56 functions as a fifth holding portion 59 for holding the upper end of the second shaft 85.

[0088] The upper end of the second shaft 85 is bonded to the third small diameter hole 56 by resin. By filling the inside of the third small diameter hole 56 with resin, the upper end of the second shaft 85 can be firmly held inside the third small diameter hole 56 by its adhesive force. The resin for fixing the upper end of the second shaft 85 to the fifth holding part 59 is preferably a silicone-based resin. By using a silicone-based resin, it becomes possible for the resin to absorb vibrations of the driving part 3 and shocks from the outside. In addition, it becomes possible to prevent defects in the joint between the upper end of the second shaft 85 and the third small diameter hole 56 that may occur due to thermal contraction (linear expansion) of the second shaft 85.

[0089] A tapered surface 85a is formed at the upper end of the second shaft 85 so that the surface area is increased. Therefore, at the upper end of the second shaft 85, it is possible to secure a sufficient adhesion area with the resin filled inside the third small diameter hole 56, and the second shaft 85 can be firmly fixed inside the third small diameter hole 56 via the resin. In addition, the tapered surface 85a is formed, which has the effect of making it easier to pour the resin into the third small diameter hole 56 from the outside (above). In addition, a similar tapered surface is formed at the lower end of the second shaft 85, and it is possible to secure a sufficient adhesion area with the resin filled inside the first small diameter hole 18 of the first fixing part 10.

[0090] 6 and 8C, a wide protrusion 53 is formed on a side portion located between the first corner 51a and the fourth corner 51d of the top plate portion 51. The wide protrusion 53 has a surface parallel to the YZ plane and protrudes downward. When the third fixing portion 50 is combined with the first fixing portion 10 and the second fixing portion 30, the wide protrusion 53 connects the top plate portion 51 and the second fixing portion 30.

[0091] 6 and 8C, a wide fixing piece 53a is formed at the lower end of the wide protruding portion 53. The Y-axis direction width of the wide fixing piece 53a is smaller than the Y-axis direction width of the wide protruding portion 53 and is approximately equal to the Y-axis direction width of each of the stepped wide portion 13 of the first fixing portion 10 and the concave wide portion 33 of the second fixing portion 30. The wide fixing piece 53a is disposed so as to straddle the stepped wide portion 13 and the concave wide portion 33 connected in the Z-axis direction, and is adhesively fixed thereto with resin.

[0092] 6 and 8A, a step is formed on the inner surface of wide protrusion 53, and a stepped side surface 57 is formed in a portion lowered by the step. A part of circuit board 100 is placed on stepped side surface 57. When a part of circuit board 100 is placed on stepped side surface 57, the surface of the circuit board and the inner surface of wide protrusion 53 (a portion adjacent to stepped side surface 57) become approximately flush with each other.

[0093] 2, the cover 90 is made of a metal such as SUS, and has a cover top plate portion 91. The cover top plate portion 91 has a generally flat plate shape, and a cover opening 92 is formed in the generally central portion. The cover opening 92 is formed at a position corresponding to the third opening 52 of the third fixed portion 50.

[0094] Four downward extending portions 93 are integrally formed on the sides of the cover top plate portion 91, and the sides of the cover top plate portion 91 are surrounded by each downward extending portion 93. Each downward extending portion 93 extends downward, and a groove portion 94 is formed between each of the adjacent downward extending portions 93, 93. As shown in FIG. 1, the downward extending portions 93 are arranged to surround the periphery of the optical driving device 1.

[0095] Next, with reference to Fig. 2 etc., a method for manufacturing the optical driving device 1 will be described, focusing mainly on a method for assembling the fixed part 4. First, the components shown in Fig. 2 are prepared. Note that the piezoelectric element 80, first shaft 81, and inertia member 82 that constitute the driving part 3 are prepared in advance in a combined state of these components. The assembly of these components is formed by bonding the lower end of the first shaft 81 to the upper end of the piezoelectric element 80 using resin, and bonding the upper end of the inertia member 82 to the lower end of the piezoelectric element 80 using resin.

[0096] The third fixing portion 50 may be prepared with a part of the circuit board 100 fixed in advance to its stepped side surface 57. The circuit board 100 has a bent portion bent at a right angle, and this bend is preferably performed after the circuit board 100 is fixed to the third fixing portion 100. As for the optical element holding portion 60, as shown in Fig. 7, an end of the pressing member 105 may be inserted into the pressing member installation hole 66, the engagement portion 106 may be engaged with the shaft sliding groove portion 64, and the sensor magnet 103 may be placed on the magnetic body installation stepped portion 63.

[0097] Next, the second fixing part 30 is combined with the third fixing part 50 shown in FIG. 2. At this time, the wide fixing piece 53a of the third fixing part 50 is engaged with the concave wide part 33 of the second fixing part 30, so that the lower end of the wide protruding part 53 of the third fixing part 50 is fixed to the upper surface of the second base part 31 of the second fixing part 30. Also, the narrow fixing piece 54a of the third fixing part 50 is engaged with the concave narrow part 34 of the second fixing part 30, so that the lower end of the narrow protruding part 54 of the third fixing part 50 is fixed to the upper surface of the second base part 31 of the second fixing part 30. As a result, the second fixing part 30 is temporarily fixed to the third fixing part 50. When the second fixing part 30 is combined with the third fixing part 50, this is done in a state where the optical element holding part 60 is disposed between the second fixing part 30 and the third fixing part 50.

[0098] Next, the assembly of the piezoelectric element 80, the first shaft 81, and the inertia member 82 is combined with the assembly of the second fixed part 30 and the third fixed part 50. More specifically, the first shaft 81 is inserted into the second large diameter hole 42 of the second fixed part 30 and the third large diameter hole 55 of the third fixed part 50 in that order. As a result, the lower end of the first shaft 81 is disposed inside the second large diameter hole 42 of the second fixed part 30 and is held by the second fixed part 30 (the second holding part 45 shown in FIG. 8B). Also, the upper end of the first shaft 81 is disposed inside the third large diameter hole 55 of the third fixed part 50 and is held by the third fixed part 50 (the third holding part 58 shown in FIG. 8B). At this time, the first shaft 81 may be clamped between a pressing member 105 fixed to the optical element holding portion 60 and an engagement portion 106, and the first shaft 81 may be engaged with the above-mentioned members with a predetermined frictional force, thereby causing the first shaft 81 to hold the optical element holding portion 60.

[0099] Next, the first fixed part 10 is combined with the assembly of the second fixed part 30 and the third fixed part 50. The lower end of the second shaft 85 is previously bonded and fixed with resin inside the first small diameter hole 18 of the first fixed part 10, and the lower end of the second shaft 85 is firmly held by the first fixed part 10. The resin used at this time is preferably an epoxy resin.

[0100] When combining the first fixed part 10 with the second fixed part 30 and the third fixed part 50, the limiting convex part 19 of the first fixed part 10 is engaged with the limiting concave part 44 (Figure 5) of the second fixed part 30, while the upper surface of the first base part 11 of the first fixed part 10 is abutted against the lower surface of the second base part 31 of the second fixed part 30.

[0101] Moreover, an inertia member 82 is disposed inside fixing recess 17 of first fixed portion 10, and inertia member 82 is held by first fixed portion 10 (first holding portion 21 shown in FIG. 8B).

[0102] Furthermore, the second shaft 85 is inserted through the second small diameter hole 43 of the second fixing part 30 and then through the third small diameter hole 56 of the third fixing part 50. At this time, as shown in Fig. 7, the second shaft 85 is sandwiched between a pair of contact protrusions 69a, 69a (Fig. 3B) formed on a pair of shaft fixing protrusions 69, 69 of the optical element holding part 60. This causes the fixing protrusions 69, 69 to frictionally engage with the second shaft 85 with a predetermined frictional force, making it possible to fix the optical element holding part 60 by the second shaft 85 so as to be movable in the Z-axis direction.

[0103] Next, the inertia member 82 shown in FIG. 2 is bonded and fixed inside the fixing recess 17 with resin, and the inertia member 82 is firmly held by the first fixing part 10. The lower end of the first shaft 81 is bonded and fixed inside the second large diameter hole 42 with resin, and the lower end of the first shaft 81 is firmly held by the second fixing part 30. The upper end of the first shaft 81 is bonded and fixed inside the third large diameter hole 55 with resin, and the upper end of the first shaft 81 is firmly held by the third fixing part 50. When performing the bonding and fixing, it is preferable to use a silicone-based resin. The timing of performing the above bonding and fixing is not particularly limited, and may be performed, for example, when the assembly of the piezoelectric element 80, the first shaft 81, and the inertia member 82 is combined with the assembly of the second fixing part 30 and the third fixing part 50.

[0104] Furthermore, the upper end of the second shaft 85 is adhesively fixed inside the third small diameter hole 56 with resin, and the upper end of the second shaft 85 is firmly held by the third fixing part 50. The resin used in this case is preferably a silicone-based resin.

[0105] As described above, in the optical driving device 1 according to this embodiment, as shown in FIG. 2 and FIG. 8B, the fixed part 4 has the first fixed part 10 and the second fixed part 30 supported by the first fixed part 10, and the second fixed part 30 holds the driving part 3. That is, the fixed part 4 in this embodiment is divided into two parts, the first fixed part 10 and the second fixed part 30, and the second fixed part 30 supported by the first fixed part 10 makes it possible to hold the driving part 3 (the lower end part of the first shaft 81) by the second holding part 45 different from the first holding part 21 to be held by the first fixed part 10. This realizes the holding of the driving part 3 by the first fixed part 10 and the second fixed part 30, and makes it possible to firmly hold the driving part 3 by the fixed part 4. Therefore, the resistance of the driving part 3 to loads or external forces is increased, and defects such as damage or collapse of the driving part 3 are effectively prevented, and a highly reliable optical driving device 1 can be realized.

[0106] Furthermore, by dividing the fixed portion 4 into the first fixed portion 10 and the second fixed portion 30, when assembling the drive portion 3 and the fixed portion 4, it is possible to combine the first fixed portion 10 with the second fixed portion 30 in a state in which the drive portion 3 (an assembly of the piezoelectric element 80, the first shaft 81, and the inertia member 82) is combined with the second fixed portion 30. In this case, it is possible to easily dispose the drive portion 3 (particularly the piezoelectric element 80 and the inertia member 82) inside the fixed portion 3 (between the first fixed portion 10 and the second fixed portion 30), and the assembly of the drive portion 3 and the fixed portion 4 becomes easy.

[0107] Moreover, in this embodiment, the second fixing portion 30 holds the lower end of the first shaft 81 in the second large diameter hole 42. Therefore, the resistance to load or external force is increased at the lower end of the first shaft 81, and problems such as breakage of the first shaft 81 can be effectively prevented.

[0108] Moreover, in this embodiment, the driving unit 3 has an inertia member 82, and the first fixing portion 10 holds the inertia member 82. Therefore, the driving unit 3 can be held by the first fixing portion 10 (fixing recess 17) and the second fixing portion 30 (second large diameter hole 42), and the driving unit 3 is firmly held by the fixing portion 4, effectively preventing problems such as damage to the driving unit 3.

[0109] In this embodiment, the fixed portion 4 has a third fixed portion 50, and the third fixed portion 50 holds the drive portion 3 (the upper end portion of the first shaft 81). Therefore, the drive portion 3 can be held by the second fixed portion 30 (second large diameter hole 42) and the third fixed portion 50 (third large diameter hole 55), so that the drive portion 3 is firmly held by the fixed portion 4, and defects such as breakage of the drive portion 3 can be effectively prevented.

[0110] In this embodiment, the third fixed part 50 is supported by the first fixed part 10 and the second fixed part 30 via the first shaft 81. In this case, the first shaft 81 serves as a pillar for supporting the third fixed part 50 on the first fixed part 10 and the second fixed part 30, and the third fixed part 50 does not need to be provided with the pillar, so that the configuration of the third fixed part 50 can be simplified. In addition, by adopting the above-mentioned configuration, the first shaft 81 exerts a function as a part of the fixed part 4, and the third fixed part 50 can be fixed to the first fixed part 10 and the second fixed part 30 via the first shaft 81 with sufficient strength.

[0111] In this embodiment, the lower end of the first shaft 81 is bonded to the second fixed portion 30 (second large diameter hole 42) with resin, the upper end of the first shaft 81 is bonded to the third fixed portion 50 (third large diameter hole 55) with resin, and the inertia member 82 is bonded to the first fixed portion 10 (fixing recess 17). Therefore, the driving portion 3 can be held by adhesion at three different positions by the fixing portions 10, 30, 50, and therefore the driving portion 3 can be firmly held by the fixing portion 4, and defects such as damage to the driving portion 3 can be effectively prevented.

[0112] In this embodiment, the first fixed part 10 is formed with a limiting protrusion 19 that limits the relative movement of the second fixed part 20, and the second fixed part 20 is formed with a limiting recess 44 that corresponds to the limiting protrusion 19. By combining the first fixed part 10 with the second fixed part 30 in a state in which the limiting protrusion 19 and the limiting recess 44 are engaged with each other, it is possible to prevent the second fixed part 30 from shifting in position or rotating relative to the first fixed part 10.

[0113] In this embodiment, the limiting protrusion 19 is located at a position spaced above the first holding portion 21 that holds the drive portion 3 (inertia member 82) of the first fixed portion 10 (fixing recess 17). Therefore, an engagement structure can be easily formed between the first fixed portion 10 and the second fixed portion 30 by the limiting protrusion 19 and the limiting recess 44.

[0114] In this embodiment, a ring-shaped groove 20 is formed on the surface of the first fixed part 10 (first base part 11) so as to surround the periphery of the limiting protrusion 19 in order to prevent interference with the second fixed part 20. Therefore, when the limiting protrusion 19 and the limiting recess 44 are engaged with each other, it is possible to prevent floating from occurring in the meshing portion between the limiting protrusion 19 and the limiting recess 44, and the second fixed part 30 can be satisfactorily combined with the first fixed part 10.

[0115] In this embodiment, a resin-filled space 40 is formed between the first fixing part 10 (first base part 11) and the second fixing part 30 (second base part 31), and the resin-filled space 40 is filled with resin. Therefore, the first fixing part 10 and the second fixing part 30 can be firmly combined via the resin. Furthermore, by adopting the above-mentioned configuration, it is possible to prevent floating from occurring at the joint between the first fixing part 10 and the second fixing part 30 when the first fixing part 10 and the second fixing part 30 are combined, and the first fixing part 10 can be well combined with the second fixing part 30.

[0116] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0117] In the above embodiment, the limiting protrusion 19 was formed in the first fixed portion 10 and the limiting recess 44 was formed in the second fixed portion 30, but the limiting protrusion 19 may also be formed in the second fixed portion 20 and the limiting recess 44 may also be formed in the first fixed portion 10.

[0118] In the above embodiment, the lower part of the drive unit 3 is held by the first fixing portion 10 (fixing recess 17) and the second fixing portion 30 (second large diameter hole 42), but the lower part of the drive unit 3 may be held by only the second fixing portion 30.

[0119] In the above embodiment, the arrangement of the position sensor 102 and the sensor magnet 103 may be reversed. [Explanation of symbols]

[0120] 1...Optical drive unit 2...Movable part 3. Drive unit 4…Fixed part 10…First fixed part 19…Limited convexity 20…Ring-shaped groove 21...First holding part 30…Second fixed part 40…Resin filling space 44…Restriction recess 45...Second holding part 50…Third fixed part 60...Optical element holding part 80...Piezoelectric element 81…First shaft 82...Inertia member

Claims

1. a movable portion having an opening for mounting an optical element; A drive unit that movably holds the movable unit; A fixing portion that holds the driving portion, The fixing portion has a first fixing portion and a second fixing portion supported by the first fixing portion, The second fixing portion holds the driving portion, the first fixed portion has a first opening formed at a position corresponding to the element installation opening of the movable portion, the second fixing portion has a second opening formed at a position corresponding to the first opening of the first fixing portion, the driving section includes a piezoelectric element, a shaft connected to one end of the piezoelectric element, and an inertia member connected to the other end of the piezoelectric element and applying an inertial force to the piezoelectric element; The second fixing portion holds the other end of the shaft, The first fixed portion is an optical driving device that holds the inertia member.

2. The fixing portion further includes a third fixing portion supported by the first fixing portion or the second fixing portion, The third fixing portion holds one end of the shaft, The optical driving device according to claim 1 , wherein the third fixed portion has a third opening formed at a position corresponding to the first opening of the first fixed portion and the second opening of the second fixed portion.

3. The optical driving device according to claim 2 , wherein the third fixed portion is supported by the first fixed portion or the second fixed portion via the shaft.

4. 4. The optical driving device according to claim 2 or 3, wherein the other end of the shaft is adhered to the second fixed portion, the one end of the shaft is adhered to the third fixed portion, and the inertia member is adhered to the first fixed portion.

5. An optical driving device as described in any one of claims 1 to 4, wherein one of the first fixed portion and the second fixed portion is formed with a convex portion that limits the relative movement of the other, and the other is formed with a concave portion corresponding to the convex portion.

6. The optical driving device according to claim 5 , wherein the convex portion or the concave portion is located at a position spaced to one side from a holding position where the first fixing portion holds the driving portion.

7. 7. The optical driving device according to claim 5, wherein a groove is formed on a surface of either the first fixed portion or the second fixed portion so as to surround the periphery of the convex portion and prevent interference with the other fixed portion.

8. A gap is partially formed between the first fixed portion and the second fixed portion, 8. The optical driving device according to claim 1, wherein the gap is filled with a resin.

Images