CN111902757A - Lens driving device and camera module - Google Patents

Abstract

A lens driving device (101) according to an embodiment of the present invention includes: a lens holding member (2) capable of holding a lens body; a plate spring (6) that supports the lens holding member (2) so as to be movable in the direction of the optical axis (JD); a coil (3) held by the lens holding member (2); and a magnet (5) opposed to the coil (3). The plate spring (6) includes: an upper plate spring (16) disposed above the lens holding member (2); and a lower plate spring (26) disposed below the lens holding member (2). The upper plate spring (16) connects the lens holding member (2) and the housing (4) with 2 elastic arm portions (16 g).

Description

Lens driving device and camera module

Technical Field

The present invention relates to a lens driving device mounted on, for example, a portable device with a camera, and a camera module including the lens driving device.

Background

Conventionally, there is known a lens driving device including: a lens holding member capable of holding a lens body; a coil disposed on an outer periphery of the lens holding member; and an upper plate spring and a lower plate spring that support the lens holding member so as to be movable in the direction of the optical axis (see patent document 1). Each of the upper leaf spring and the lower leaf spring includes 4 arm portions connecting the inner portion and the outer portion.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2008-112200

Disclosure of Invention

Problems to be solved by the invention

However, in the above-described configuration in which the inner portion and the outer portion are connected by 4 arm portions, a space for accommodating the 4 arm portions is required. Therefore, this hinders the miniaturization of the lens holding member.

Therefore, it is desirable to provide a lens driving device capable of further miniaturization.

Means for solving the problems

The lens driving device according to an embodiment of the present invention includes: a stationary-side member; a lens holding member capable of holding a lens body; a plate spring that supports the lens holding member so as to be movable in the direction of the optical axis; a coil held by the lens holding member; and a magnet facing the coil, wherein the plate spring includes: an upper plate spring disposed above the lens holding member; and a lower plate spring disposed below the lens holding member, at least one of the upper plate spring and the lower plate spring connecting the fixed member and the lens holding member with 2 elastic arm portions.

Effects of the invention

According to the above aspect, a lens driving device capable of further downsizing is provided.

Drawings

Fig. 1 is an exploded perspective view of a lens driving device.

Fig. 2A is an upper perspective view of the lens driving device.

Fig. 2B is a front view of the lens driving device.

Fig. 3A is a plan view of the lens driving device.

Fig. 3B is a bottom view of the lens driving device.

Fig. 4A is an upper perspective view of the lens driving device in a state where the housing is omitted.

Fig. 4B is a right side view of the lens driving device in a state where the housing is omitted.

Fig. 5A is an upper perspective view of the lens holding member.

Fig. 5B is an upper perspective view of the lens holding member around which the coil is wound.

Fig. 6A is a lower perspective view of the lens holding member.

Fig. 6B is a lower perspective view of the lens holding member around which the coil is wound.

Fig. 7A is a plan view of the lens holding member.

Fig. 7B is a right side view of the lens holding member.

Fig. 8A is a lower perspective view of the lens holding member.

Fig. 8B is a lower perspective view of the lens holding member around which the coil is wound.

Fig. 9A is an enlarged view of a part of the lens holding member.

Fig. 9B is an enlarged view of another part of the lens holding member.

Fig. 10A is a bottom view of the lens driving device with parts omitted.

Fig. 10B is a bottom view of the lens driving device with parts omitted.

Fig. 11A is a plan view of the upper leaf spring.

Fig. 11B is a bottom view of the lower leaf spring.

Fig. 12A is a diagram illustrating an example of connection between a leaf spring and a coil in the lens driving device.

Fig. 12B is a diagram illustrating an example of connection between the leaf spring and the coil in the lens driving device.

Fig. 13A is an upper perspective view of the base member of the lens driving device.

Fig. 13B is an upper perspective view of the base member to which the lower leaf spring is assembled.

Fig. 13C is an upper perspective view of the metal member embedded in the base member.

Fig. 14A is a left side view of the projection formed on the lens holding member.

Fig. 14B is a left side view of the projection formed on the lens holding member.

Fig. 15A is a perspective view of the upper side of the protruding portion formed on the lens holding member.

Fig. 15B is a perspective view of the upper side of the protruding portion formed on the lens holding member.

Fig. 16A is a left side view of an example of the protruding portion.

Fig. 16B is a left side view of another example of the protruding portion.

Fig. 16C is a left side view of another example of the protruding portion.

Fig. 17 is a plan view of the upper leaf spring.

Fig. 18 is a bottom view of the lower leaf spring.

Detailed Description

Hereinafter, a lens driving device 101 according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is an exploded perspective view of a lens driving device 101. Fig. 2A is an upper perspective view of the lens driving device 101, and fig. 2B is a front view of the lens driving device 101 as viewed from the Y2 side. Fig. 3A is a plan view of the lens driving device 101, and fig. 3B is a bottom view of the lens driving device 101. Fig. 4A is an upper perspective view of the lens driving device 101 with the housing 4 omitted, and corresponds to fig. 2A. Fig. 4B is a right side view of the lens driving device 101 in a state where the housing 4 is omitted, as viewed from the X1 side.

As shown in fig. 1, the lens driving device 101 includes: a lens holding member 2 capable of holding a lens body (not shown); a drive mechanism MK that moves the lens holding member 2 in the direction of the optical axis JD of the lens body (Z-axis direction); a plate spring 6 that supports the lens holding member 2 movably in the direction of the optical axis JD; and a fixed-side member RG to which the plate spring 6 is fixed. The lens body is, for example, a cylindrical lens barrel including at least 1 lens, and is configured such that the central axis thereof is along the direction of the optical axis JD.

As shown in fig. 1, drive mechanism MK includes: a coil 3 wound in an octagonal ring shape; and 4 magnets 5 arranged to face the coil 3. Stationary-side member RG includes case 4 and base member 18 in which metal member 7 is embedded. The metal member 7 includes a terminal 7A and a terminal 7B for electrically connecting to the outside. The plate spring 6 includes: an upper plate spring 16 disposed between the lens holding member 2 and the housing 4; and a lower plate spring 26 disposed between the lens holding member 2 and the base member 18. The lower leaf spring 26 includes a lower leaf spring 26A and a lower leaf spring 26B. The housing 4 has: a substantially rectangular cylindrical outer wall portion 4A; and a flat annular upper surface portion 4B provided so as to be continuous with an upper end (end on the Z1 side) of the outer wall portion 4A. The outer wall portion 4A has: a pair of 1 st side plate portions 4a1 facing each other; and a pair of 2 nd side panel portions 4a2 perpendicular to the 1 st side panel portion 4a1 and opposed to each other.

The lens driving device 101 has a substantially rectangular parallelepiped shape, and is mounted on a substrate (not shown) on which an imaging element (not shown) is mounted. The substrate, the lens driving device 101, the lens body mounted on the lens holding member 2, and the imaging element mounted on the substrate so as to face the lens body constitute a camera module. The coil 3 is connected to a power supply via the lower plate spring 26A, the lower plate spring 26B, the terminal 7A, the terminal 7B, and the substrate. Therefore, the lower plate springs 26A and 26B are formed of a conductive member such as metal. When a current flows through the coil 3, the driving mechanism MK generates an electromagnetic force in the direction along the optical axis JD.

The lens driving device 101 moves the lens holding member 2 in the direction of the optical axis JD on the Z1 side (object side) of the imaging element by the electromagnetic force. The lens driving device 101 is configured to be able to move the lens holding member 2 in a direction away from the image pickup device to perform macro image pickup and to be able to move the lens holding member 2 in a direction close to the image pickup device to perform infinity image pickup.

Next, the lens holding member 2 and the drive mechanism MK will be described. Fig. 5A is an upper perspective view of the lens holding member 2, and fig. 5B is an upper perspective view of the lens holding member 2 illustrating a state in which the coil 3 is wound around the lens holding member 2 of fig. 5A. Fig. 6A is a lower perspective view of the lens holding member 2, and fig. 6B is a lower perspective view of the lens holding member 2 showing a state in which the coil 3 is wound around the lens holding member 2 of fig. 6A. Fig. 7A is a plan view of the lens holding member 2, and fig. 7B is a right side view of the lens holding member 2 as viewed from the X1 side. Fig. 8A is a lower perspective view of the lens holding member 2, and fig. 8B is a lower perspective view of the lens holding member 2 showing a state in which the coil 3 is wound around the lens holding member 2 shown in fig. 8A. Fig. 9A is an enlarged view of a portion S shown in fig. 8B, and fig. 9B is an enlarged view of a portion P shown in fig. 6B. Fig. 10A is a bottom view of the lens driving device 101 in a state where the metal member 7 and the base member 18 are omitted, and fig. 10B is a bottom view of the lens driving device 101 in a state where the lower plate spring 26 and the lens holding member 2 are further omitted.

In the present embodiment, the lens holding member 2 is manufactured by injection molding a synthetic resin such as a Liquid Crystal Polymer (LCP). Specifically, as shown in fig. 5A, the lens holding member 2 includes: a cylindrical portion 12 having a through hole formed along the direction of the optical axis JD; and a flange portion (flange portion) 52 formed at a portion on the imaging element side (Z2 side) in the direction of the optical axis JD. In the present embodiment, the portion of the cylindrical portion 12 on the object side (Z1 side) in the direction of the optical axis JD is formed in a cylindrical shape.

The cylindrical portion 12 may be provided with a screw groove on an inner peripheral surface thereof so as to mount a lens body. However, in the present embodiment, the lens body is fixed to the cylindrical portion 12 with an adhesive. Therefore, no thread groove is formed in the cylindrical portion 12. As shown in fig. 5A, the cylindrical portion 12 is provided with a base portion 12d having 2 recesses 12dh on the end surface on the object side. As shown in fig. 4A, the inner portion 16i of the upper leaf spring 16 is placed on the base portion 12 d.

As shown in fig. 5A, a coil support portion 12j as an outer wall portion that supports the coil 3 from the inside is provided on the outer peripheral surface of the cylindrical portion 12. In the present embodiment, the coil support portion 12j has an octagonal outer shape as a whole in a plan view so as to be able to support the octagonal ring-shaped coil 3. However, there are also portions on the outer peripheral surface of the cylindrical portion 12 where the coil support portion 12j is not formed. On the object side of the coil support portion 12j, a flange portion 12h (see fig. 7A and 7B) is formed so as to protrude radially outward so as to face the flange portion 52 in the direction of the optical axis JD. Further, as shown in fig. 5B, the coil 3 is wound in an octagonal ring shape on the outer peripheral surface side of the lens holding member 2 so as to be supported by the coil supporting portion 12j and sandwiched between the flange portion 12h and the flange portion 52 in the direction of the optical axis JD. In this configuration, the brim portion 12h and the flange portion 52 function as a restricting portion that restricts movement of the coil 3 (winding portion 13) in the direction of the optical axis JD.

The flange portion 52 projects radially outward from the outer peripheral surface of the cylindrical portion 12 at the imaging element side (Z2 side). The coil 3 (winding portion 13) is disposed on the object side of the flange portion 52.

The flange portion 52 includes: 2 protruding portions 72 of a square convex shape protruding obliquely outward from the surface on the imaging element side (Z2 side) as indicated by an arrow AR1 in fig. 6A; and 4 circular convex protruding portions 2t protruding downward (Z2 direction) from the surface on the imaging element side (Z2 side).

The projection 72 includes, as shown in fig. 6B: a protruding portion 72A corresponding to the wire material on the winding start end side of the coil 3 (winding portion 13); and a protruding portion 72B corresponding to the wire material on the winding end side of the coil 3 (winding portion 13). Both ends of the wire rod constituting the coil 3 are wound around the protruding portions 72 and held. The winding of the wire rod is performed using, for example, an automatic winding machine.

The protruding portion 72 is preferably configured such that a portion around which the wire is wound has a quadrangular prism shape as shown in fig. 6A. In this case, among the edges corresponding to the 4 sides, the edge located between the side where the wire is initially contacted and the side where the 2 nd contact is made is preferably bent. The bent edge can prevent an excessive force from being applied to the surface of the wire in contact with the edge when the wire of the coil 3 is wound around the protruding portion 72. In addition, the other 3 edges may be formed with corners (not curved). The protrusion 72 may be formed in a cylindrical shape or an elliptical cylindrical shape in a portion around which the wire rod is wound, or may be formed in a polygonal prism shape such as a triangular prism shape, a pentagonal prism shape, or a hexagonal prism shape.

As shown in fig. 6A and 10A, the protruding portion 2t includes: 2 protruding portions 2t corresponding to the lower leaf spring 26A; and 2 protruding portions 2t corresponding to the lower leaf spring 26B. An inner portion 26i of each of the lower leaf springs 26A and 26B is attached and fixed to the protruding portion 2 t. The inner portions 26i of the lower leaf springs 26A and 26B are fixed by hot riveting or cold riveting the protruding portions 2t inserted through the through holes (see fig. 11B) formed in the inner portions 26 i. In the drawing, the protruding portion 2t is shown in a state in which the tip is deformed after hot riveting or cold riveting.

Next, the driving mechanism MK of the lens driving device 101 will be described. As shown in fig. 10B, the drive mechanism MK includes a coil 3 and 4 magnets 5 arranged to face corners located at four corners of the case 4. Further, the driving mechanism MK generates a driving force (thrust) by the current flowing through the coil 3 and the magnetic field generated by the magnet 5, and can move the lens holding member 2 up and down in the direction of the optical axis JD.

The coil 3 is formed by winding a conductive wire around the outer periphery of the lens holding member 2 as shown in fig. 6B. The coil 3 includes: a winding portion 13 formed by winding in an octagonal annular shape; and an extension portion 33 extending from the winding portion 13 and wound around the protruding portion 72. In fig. 6B, the winding portion 13 is not illustrated in a detailed wound state of the conductive wire material having a surface covered with the insulating member for clarity. The same applies to other drawings showing the winding portion 13.

The extension 33 includes: an extension portion 33A connected to an end portion (winding start portion) of the winding portion 13 on the winding start end side of the coil 3 and on the inner peripheral side of the winding portion 13; and an extension portion 33B connected to an end portion (winding end portion) of the winding portion 13 located on the winding end side of the coil 3 and on the outer peripheral side of the winding portion 13.

Specifically, the extension 33A includes, as shown in fig. 9A: a winding portion 33m wound around the protruding portion 72A; and a connecting portion 33c between the winding portion 13 and the winding portion 33 m. The extension 33B includes, as shown in fig. 9B: a winding portion 33m wound around the protruding portion 72B; and a connecting portion 33c between the winding portion 13 and the winding portion 33 m.

In the present embodiment, the wire of the coil 3 is wound around the protrusion 72A of the lens holding member 2 before being wound around the outer periphery of the lens holding member 2 with respect to the extension portion 33A. In the example shown in fig. 9A, a part of the wire of the coil 3 is wound at the projection 72A by 3 turns. Thereby, the winding portion 33m is formed on the protruding portion 72A, and a part of the extending portion 33A is held by the protruding portion 72A. However, the wire of the coil 3 may be wound around the outer periphery of the lens holding member 2 and then wound around the protrusion 72A in the extension portion 33A.

Next, the wire is wound around the outer periphery of the lens holding member 2. At this time, as shown in fig. 9A, the connection portion 33c extends from the lower side of the flange portion 52 toward the upper side, and is connected to the winding start portion of the winding portion 13, constituting the inner peripheral side of the winding portion 13.

The winding portion 13 of the coil 3 wound around the outer periphery of the lens holding member 2 is disposed at a position surrounding the periphery of the lens holding member 2 as shown in fig. 5B. The winding portion 13 is held on the object side of the flange portion 52 by being sandwiched between the flange portion 52 and the flange portion 12h in a state of being supported from the inside by the coil support portion 12j (see fig. 5A). Since the inner peripheral surface of the winding portion 13 is supported by the coil support portion 12j in an isotropic balance manner, the winding portion 13 is held by the lens holding member 2 in a state where the central axis of the coil 3 coincides with the central axis of the lens holding member 2. Therefore, the optical axis JD of the lens body held by the lens holding member 2 is configured to easily coincide with the central axes of the lens holding member 2 and the coil 3, respectively. The winding portion 13 of the coil 3 may be fixed to the coil support portion 12j by an adhesive.

When the winding of the linear material around the outer periphery of the lens holding member 2 is completed, the extension portion 33B connected to the end portion on the winding end side of the winding portion 13 is drawn out from the object side of the flange portion 52 toward the imaging element side as shown in fig. 9B. Specifically, the connection portion 33c extends to face the lower end face of the winding portion 13, and the winding portion 33m is wound around the protruding portion 72B of the lens holding member 2. In the example shown in fig. 9B, the extension portion 33B is wound 3 turns at the projection portion 72B.

Next, the case 4 will be explained. In the present embodiment, the case 4 is manufactured by punching and drawing a plate material made of a nonmagnetic metal such as austenitic stainless steel. Since the housing 4 is formed of a nonmagnetic metal, even when another lens driving device is disposed adjacent to the lens driving device 101 in a portable device of a twin-lens camera type or the like, the configuration of the driving machine included in the other lens driving device is not adversely affected in terms of magnetism. Specifically, the housing 4 has a box-like outer shape defining the housing portion 4s as shown in fig. 1. Further, the housing 4 includes: a rectangular annular outer wall portion 4A; and a flat upper surface portion 4B provided so as to be continuous with an upper end (end portion on the Z1 side) of the outer wall portion 4A. In the upper surface portion 4B, a plurality of (4 in the present embodiment) receiving portions 4R are formed at portions facing the magnets 5. The receiving portion 4R is formed such that its upper surface (surface on the Z1 side) is recessed, that is, its lower surface (surface on the Z2 side) protrudes toward the magnet 5 side (Z2 side). As shown in fig. 2A, a circular opening 4k is formed in the upper surface portion 4B. The case 4 configured as described above is configured to house the coil 3 and the magnet 5 in the housing portion 4s as shown in fig. 10B, and is coupled to the base member 18 to form a frame together with the base member 18 as shown in fig. 2A. However, the case 4 may be replaced with a cover made of a magnetic metal such as iron. In this case, the case 4 functions as a yoke.

Next, the magnet 5 constituting the drive mechanism MK will be described. The magnet 5 has a prismatic shape as shown in fig. 1, and is disposed so as to be housed in the case 4. Specifically, as shown in fig. 10B, the 4 magnets 5 are located outside the coil 3 and are arranged so as to face the corner portions located at the four corners of the case 4. Further, the 4 magnets 5 are fixed to the inner surfaces of the 1 st side plate 4a1 and the 2 nd side plate 4a2 by an adhesive. The 4 magnets 5 are arranged such that, for example, the inside is an N pole and the outside is an S pole.

Next, the leaf spring 6 and the fixed-side member RG will be described. Fig. 11A and 11B are diagrams for explaining the plate spring 6. Fig. 11A is a plan view of the upper leaf spring 16, and fig. 11B is a bottom view of the lower leaf spring 26. Fig. 12A and 12B are diagrams illustrating an example of a connection state between the lower leaf spring 26B and the coil 3. Specifically, fig. 12A is an enlarged view of the portion T shown in fig. 10A, and fig. 12B is an enlarged view of the lower plate spring 26B, the coil 3, and the lens holding member 2 when the portion T shown in fig. 10A is viewed from the X2 side. In fig. 12A and 12B, the bonding material CA such as solder is shown by cross hatching. Fig. 13A to 13C are views for explaining base member 18 constituting fixed-side member RG. Specifically, fig. 13A is an upper perspective view of the base member 18, fig. 13B is an upper perspective view of a state in which the lower leaf spring 26 is assembled to the base member 18, and fig. 13C is an upper perspective view of the metal member 7 embedded in the base member 18.

The plate spring 6 is made of a metal plate having a copper alloy as a main material. As shown in fig. 1, the plate spring 6 includes: an upper plate spring 16 disposed between the lens holding member 2 and the housing 4; and a lower plate spring 26 disposed between the lens holding member 2 and the base member 18. In a state where the lens holding member 2 is engaged with each of the plate springs 6 (the upper plate spring 16, the lower plate spring 26A, and the lower plate spring 26B), the plate spring 6 supports the lens holding member 2 in the air so that the lens holding member 2 can move in the direction of the optical axis JD (Z-axis direction). The lower plate spring 26 functions as a power supply member for supplying current to the coil 3. Therefore, the lower plate spring 26A is electrically and physically connected to one end of the coil 3, and the lower plate spring 26B is electrically and physically connected to the other end of the coil 3. In the present embodiment, the upper plate spring 16 is formed of a non-conductive member because no current flows. A spacer may be disposed between the upper leaf spring 16 and the housing 4. This is to prevent the lens holding member 2 from colliding with the housing 4 when the lens holding member 2 moves in the Z1 direction. In addition, in the case where the spacer is provided, the spacer constitutes a part of the fixed-side member RG.

As shown in fig. 11A, the upper leaf spring 16 has a substantially rectangular outer shape, and includes: an inner portion 16i as a movable side support portion fixed to the lens holding member 2; an outer portion 16e serving as a fixed-side support portion fixed to fixed-side member RG; and an elastic arm portion 16g located between the inner portion 16i and the outer portion 16 e. The elastic arm portion 16g includes a1 st elastic arm portion 16g1 and a2 nd elastic arm portion 16g 2. The outer portion 16e has 4 corner portions 16b and 4 bridge portions 16r connecting 2 of the 4 corner portions 16 b. The corner portion 16B is held and fixed by a receiving portion 4R (see fig. 1) formed on the upper surface portion 4B of the housing 4 and the magnet 5. Thus, the housing 4 and the magnet 5 function as the fixed-side member RG.

When the upper leaf spring 16 is assembled to the lens driving device 101, as shown in fig. 4A, the inner portion 16i is placed on the base portion 12d of the lens holding member 2 (see fig. 5A). Further, the inner portion 16i and the base portion 12d are fixed by an adhesive, whereby the inner portion 16i is fixed to the lens holding member 2. As shown in fig. 4B, the outer portion 16e is in contact with the upper surface (surface on the Z1 side) of the magnet 5, and is sandwiched and fixed between the housing 4 and the magnet 5.

The upper plate spring 16 is formed to be substantially point-symmetrical with respect to a black point representing the optical axis JD of the lens body as shown in fig. 11A. The upper leaf spring 16 is fixed to the lens holding member 2 at an inner portion 16i and to the housing 4 at an outer portion 16 e. Therefore, the upper leaf spring 16 can support the lens holding member 2 in the air with good balance.

As shown in fig. 11B, the lower leaf spring 26A and the lower leaf spring 26B are configured such that their inner shapes are substantially semicircular. Further, the lower leaf spring 26A and the lower leaf spring 26B include: an inner portion 26i as a movable side support portion fixed to the image pickup device side of the lens holding member 2; an outer portion 26e serving as a fixed-side support portion fixed to the fixed-side member RG; and an elastic arm portion 26g located between the inner portion 26i and the outer portion 26 e. Specifically, the lower leaf spring 26A includes an inner portion 26Ai, an outer portion 26Ae, and an elastic arm portion 26 Ag. The lower leaf spring 26B includes an inner portion 26Bi, an outer portion 26Be, and an elastic arm portion 26 Bg.

The inner portion 26Ai and the inner portion 26Bi include, as shown in fig. 11B: 2 inner joint portions 26c that engage with the lens holding member 2; a connecting plate portion 26h opposed to the extension portion 33 of the coil 3; and 2 1 st coupling portions 26p that couple the 2 inner joint portions 26c to the web portions 26h, respectively.

When the lower leaf springs 26A and 26B are assembled to the lens driving device 101, the 4 protruding portions 2t of the lens holding member 2 shown in fig. 6A are inserted into and fitted into circular through holes provided in the inner joint portions 26c of the lower leaf springs 26A and 26B shown in fig. 11B. Thereby, the inner portions 26Ai and 26Bi are positioned and fixed to the lens holding member 2. Specifically, the inner portions 26Ai and 26Bi are fixed to the lens holding member 2 by, for example, hot riveting or cold riveting the protruding portions 2t of the lens holding member 2.

Hereinafter, the relationship between the lower plate spring 26B, the lens holding member 2, and the coil 3 will be mainly described. However, the same description as that for the lower leaf spring 26B applies to the lower leaf spring 26A.

As shown in fig. 12A and 12B, the connecting plate portion 26h of the inner portion 26Bi of the lower leaf spring 26B faces the flange portion 52 of the lens holding member 2 when the lens driving device 101 is assembled. That is, the surface of the connecting plate 26h on the object side (Z1 side) faces the surface of the flange 52 on the imaging element side (Z2 side) as shown in fig. 12A. Further, as shown in fig. 12B, the connection portion 33c of the extension portion 33A of the coil 3 is connected to the winding start portion of the winding portion 13 on the object side (Z1 side) of the inner portion 26Bi of the lower plate spring 26B.

As shown in fig. 12A, the connecting plate 26h of the inner portion 26Bi is provided with a through portion 26t cut out from both sides. The through portion 26t is provided such that the width of the connecting plate portion 26h in the X axis direction corresponds to the width of the protruding portion 72A in bottom view. According to this arrangement, the through portion 26t prevents the joining material CA from being conducted and spread on the surface of the lower leaf spring 26B on the Z2 side. A tongue portion 26s is formed at a position corresponding to the X2 side surface of the projection 72A. According to this configuration, the tongue portion 26s formed in the inner portion 26Bi causes the joining material CA to spread toward the surface of the protruding portion 72A on the X2 side by being easily conducted on the surface of the lower leaf spring 26B on the Z2 side. This is to securely connect the lower leaf spring 26B and the wound portion 33m via the joining material CA.

When the lower plate spring 26B is assembled to the lens holding member 2, as shown in fig. 12B, the protruding portion 72A protrudes downward (Z2 direction) from the inside portion 26Bi of the lower plate spring 26B so that the tip end thereof is positioned on the imaging element side (Z2 side) of the inside portion 26 Bi. A part of the winding portion 33m is also wound around the protruding portion 72A so as to be positioned on the imaging element side (Z2 side) of the inner portion 26 Bi. In the present embodiment, the winding portion 33m is wound around the quadrangular prism-shaped projection 72A such that all of the 3 turn portions corresponding to the 3 rd surface S3 (see fig. 14A), which is 1 of the 4 side surfaces of the projection 72A, are exposed on the Z2 side of the inner portion 26 Bi. However, the winding portion 33m may be wound around the protruding portion 72A so that 2 or 1 of the 3 turn portions corresponding to the 3 rd surface S3 on the tip side are exposed on the Z2 side of the inner portion 26 Bi.

The lower plate spring 26B and the extending portion 33A of the coil 3 may be electrically and mechanically connected to each other by a bonding material other than solder, such as a conductive adhesive in which a conductive filler such as silver particles is dispersed in a synthetic resin. The conductive adhesive may be a thermosetting type or an ultraviolet curing type.

As shown in fig. 11B, the outer portion 26Be of the lower leaf spring 26B includes an outer engagement portion 26d that engages with the base member 18. The lateral engaging portion 26d includes a1 st lateral engaging portion 26d1 and a2 nd lateral engaging portion 26d 2. In the present embodiment, the lower plate spring 26B is not provided with a coupling portion for connecting the 2 outer engaging portions 26d in order to achieve downsizing. The through hole provided in the outer joining portion 26d of the lower leaf spring 26B is fitted into the protruding portion 18t (see fig. 13A) provided on the upper surface of the base member 18. Thereby, the outer portion 26Be of the lower leaf spring 26B is positioned and fixed to the base member 18.

The lower plate spring 26A and the lower plate spring 26B are formed to be substantially point-symmetrical with respect to a black dot representing the optical axis JD of the lens body as shown in fig. 11B. Further, the lower plate spring 26A is connected to the lens holding member 2 at 2 inner engaging portions 26c and connected to the base member 18 at 2 outer engaging portions 26 d. In the present embodiment, the lower leaf spring 26A is joined to the base member 18 via the metal member 7 at the 1 st outer joining portion 26d1 by welding, and is joined to the base member 18 at the 2 nd outer joining portion 26d2 by a thermosetting adhesive. The same applies to the lower leaf spring 26B. With this configuration, the lower leaf springs 26A and 26B can support the lens holding member 2 in the air in a state of being movable in the direction of the optical axis JD with good balance.

Next, stationary-side member RG will be described. The fixed-side member RG includes: a housing 4 and a magnet 5 for fixing the upper plate spring 16; and a base member 18 for fixing the lower leaf spring 26A and the lower leaf spring 26B, respectively.

The base member 18 is manufactured by injection molding using a synthetic resin such as a liquid crystal polymer. In the present embodiment, the base member 18 is a member having a rectangular outer shape as shown in fig. 13A, and a circular opening 18k is formed at the center. Further, 6 protruding portions 18t protruding upward are provided on the surface (upper surface) of the base member 18 on the object side (Z1 side). The protruding portion 18t is inserted and fitted into a through hole provided in the outer joining portion 26d of each of the lower leaf spring 26A and the lower leaf spring 26B. At this time, the projecting portion 18t is fixed to the outer joining portion 26d by hot riveting or cold riveting.

After the projection 18t is fixed to the outer joining portion 26d by hot or cold riveting, the lower leaf spring 26 is fixed to the base member 18 by welding or an adhesive. Specifically, the 1 st outer joint part 26d1 is fixed to the base member 18 via the metal member 7 by welding, and the 2 nd outer joint part 26d2 is fixed to the base member 18 by a thermosetting adhesive.

More specifically, as shown in fig. 11B, 1 through hole through which the protruding portion 18t is inserted is formed in the 1 st outer joining portion 26d1 that is a portion where the lower leaf spring 26A is welded to the metal member 7, and 2 through holes through which the protruding portion 18t is inserted are formed in the 2 nd outer joining portion 26d2 where the lower leaf spring 26A is bonded to the base member 18 with an adhesive. When only 1 through-hole is formed in the 2 nd outer joint portion 26d2, the lower leaf spring 26A may rotate or move in parallel around the projecting portion 18t inserted through and caulked to the 1 through-hole before the adhesive is applied or when the adhesive is peeled off. The 2 through holes formed in the 2 nd outer joint portion 26d2 have an effect of suppressing or preventing the rotation and the parallel movement. However, the number of the through holes formed in the 2 nd outer joint portion 26d2 may be 1.

As shown in fig. 13A, the metal member 7 made of a metal such as copper or iron or an alloy containing these as a main component is embedded in the base member 18 by insert molding. The metal member 7 includes a terminal 7A and a terminal 7B. The terminals 7A are exposed at the exposed portions 7A1 on the upper surface (surface on the Z1 side) of the base member 18, and the terminals 7B are exposed at the exposed portions 7B1 on the upper surface (surface on the Z1 side) of the base member 18. Further, the terminal 7A and the terminal 7B, which are electrically insulated from each other, are electrically connected to a conductor portion (not shown) on the substrate on which the imaging element is mounted. The terminal 7A is electrically and physically connected to the lower leaf spring 26A at the exposed portion 7A1 by welding or the like, and the terminal 7B is electrically and physically connected to the lower leaf spring 26B at the exposed portion 7B1 by welding or the like. The lower plate spring 26A is electrically connected to one end of the coil 3, and the lower plate spring 26B is electrically connected to the other end of the coil 3. Therefore, the coil 3 can receive the supply of current through the terminal 7A, the terminal 7B, the lower leaf spring 26A, and the lower leaf spring 26B.

The base member 18 is also embedded with a connecting member 7D formed by insert molding of a metal containing copper, iron, or an alloy containing these as a main component, which is similar to the terminal 7A and the terminal 7B. As shown in fig. 2A, the connecting member 7D has a part thereof exposed from the base member 18 at a lower end portion of the four corners of the housing 4. The base member 18 is positioned by combining the inner surface of the outer wall portion 4A of the housing 4 and the side wall surface 18W of the base member 18, and then the connecting members 7D are welded to the lower end portions of the four corners of the housing 4, thereby being fixed to the housing 4. The lower surface (end surface on the Z2 side) of the outer wall portion 4A is configured to contact the upper surface (end surface on the Z1 side) of the flange portion 18F (see fig. 13A) of the base member 18.

Next, details of the protruding portion 72 will be described with reference to fig. 14A, 14B, 15A, and 15B. Fig. 14A and 14B are left side views of the protruding portion 72A, and correspond to the portion U shown in fig. 12B. Specifically, fig. 14A shows a state in which the protrusion 72A is wound before the extending portion 33A is wound, and fig. 14B shows a state in which the protrusion 72A is wound after the extending portion 33A is wound. Fig. 15A and 15B are top perspective views of the protruding portion 72B, and correspond to the portion V shown in fig. 5A. Specifically, fig. 15A shows a state in which the protrusion 72B is wound before the extending portion 33B is wound, and fig. 15B shows a state in which the protrusion 72B is wound after the extending portion 33B is wound. In fig. 15B, the winding portion 13 of the coil 3 is not shown.

In the present embodiment, the protruding portion 72A and the protruding portion 72B are in a mutually plane-symmetric relationship with respect to an XZ plane including the optical axis JD of the lens body. Therefore, the description of the projection 72A is also applied to the projection 72B. The reverse is also true.

As shown in fig. 14A, the protruding portion 72A is configured to extend obliquely left and downward along a protruding axis 72AX indicated by a dashed-dotted line on a side where the winding portion 13 of the coil 3 is not disposed, that is, on a lower side (Z2 side) than an upper surface (Z1 side) of the flange portion 52. The protrusion shaft 72AX forms an angle θ with respect to a plane HP parallel to the XY plane shown by the broken line, for example. The angle θ is, for example, 30 degrees or more and 60 degrees or less. In the present embodiment, the angle θ is 45 degrees. However, the projecting portion 72A may be configured to extend obliquely upward to the left, and a part thereof may be configured to be positioned above (on the Z1 side) the upper surface (surface on the Z1 side) of the flange portion 52. When the lens holding member 2 is viewed from the bottom surface side (Z2 side), the projection 72A may project obliquely with respect to the Y axis instead of projecting in the Y axis direction.

The projection 72A has: a central portion CP around which the extension portion 33A is wound; a root portion BP located on a side closer to the lens holding member 2 than the central portion CP; and a tip portion TP located on a side farther from the lens holding member 2 than the central portion CP. Fig. 14A shows the root portion BP, the center portion CP, and the tip portion TP divided by dotted lines.

The flat upper surface TS1 of the root portion BP is formed to be at the same height as the upper surface TS2 of the flange portion 52 in the Z-axis direction. Specifically, as shown in fig. 5A, the upper surface TS1 is disposed at intervals from the 2 adjacent upper surfaces TS2 of the flange 52, and is disposed in the middle of the 2 upper surfaces TS 2. This is to support a part of the winding portion 13 of the coil 3 together with the flange portion 52. In the present embodiment, the width of the upper surface TS1 in the radial direction of the coil 3 is formed to be about half the width of the winding portion 13 of the coil 3, but the width may be narrower or wider. The length of the coil 3 in the circumferential direction of the upper surface TS1 is formed to be about one fifth of the length of the corresponding eaves 12h, but the length may be longer or shorter. According to this structure, the root portion BP of the protruding portion 72A can prevent the winding portion 13 from moving in the Z2 direction along the optical axis JD together with the flange portion 52. Further, the root portion BP can support the winding portion 13 together with the flange portion 52, and therefore, the winding shape of the coil 3 can be stabilized. That is, the root portion BP can prevent the winding shape of the coil 3 from being disturbed.

The tip portion TP has an extension 73. The protruding portion 73 is configured to prevent the winding portion 33m of the extending portion 33A from moving toward the leading end portion TP side. That is, the extension portion 73 functions as a coming-off prevention portion that prevents the winding portion 33m from coming off the projection portion 72A. In the present embodiment, the extension portion 73 includes a1 st extension portion 73a and a2 nd extension portion 73 b. The 1 st projecting portion 73a of the projecting portion 72A is configured to project from the 1 st surface S1 of the central portion CP in the Y1 direction, which is an example of a direction not parallel to the projecting axis 72AX, as indicated by an arrow AR2A in fig. 14A. The 2 nd projecting portion 73b of the projecting portion 72A is configured to project from the 3 rd surface S3 of the central portion CP in the Z2 direction, which is another example of the direction not parallel to the projecting axis 72AX, as indicated by an arrow AR3A in fig. 14A. In this example, the 1 st projecting portion 73a is formed to project perpendicularly to the projecting direction of the 2 nd projecting portion 73 b.

Similarly, the 1 st projecting portion 73a of the projecting portion 72B is configured to project from the 1 st surface S1 of the central portion CP in the Y2 direction as indicated by an arrow AR2B in fig. 15A. The 2 nd projecting portion 73B of the projecting portion 72B is configured to project from the 3 rd surface S3 of the central portion CP in the Z2 direction as indicated by an arrow AR3B in fig. 15A. In this example, in the protruding portion 72B, the 1 st protruding portion 73a is also formed to protrude perpendicularly to the protruding direction of the 2 nd protruding portion 73B.

The extension 73 includes a3 rd extension 73c that extends in the X1 direction so as to divide the 2 nd surface S2 of the central portion CP into the 1 st segment S2a and the 2 nd segment S2b as indicated by an arrow AR4 in fig. 15A. Similarly, the protruding portion 73 includes a 4 th protruding portion 73d protruding in the X2 direction so as to divide the 4 th surface S4 of the central portion CP into 2 parts as shown by an arrow AR5 in fig. 15A.

The 1 st, 3 rd, and 4 th projecting portions 73a, 73c, and 73d are formed by parting surfaces that are parting surfaces of a mold used when molding the lens holding member 2. However, the 3 rd extending portion 73c and the 4 th extending portion 73d may be omitted. That is, the protrusions 72A and 72B may be formed to be coplanar with the 1 st and 2 nd portions S2A and S2B in the 2 nd face S2 of the central portion CP. The same applies to the 4 th surface S4.

According to this configuration, the 1 st projecting portion 73A and the 2 nd projecting portion 73b projecting perpendicularly to each other in the projecting portion 72A can cooperate with each other to more reliably prevent the winding portion 33m of the extending portion 33A from moving toward the tip portion TP side along the projecting shaft 72 AX. The same applies to the projection 72B. Also, the 1 st protruding portion 73a is formed to protrude in a direction perpendicular to the drawing direction of the mold, and the 2 nd protruding portion 73b is formed to protrude in the drawing direction of the mold. That is, the protruding portion 73 is formed so that undercut is not generated. Therefore, the structure does not unduly complicate the configuration of the mold. The same applies to the projection 72B.

The length of the central portion CP of the protrusion 72A along the protrusion axis 72AX is determined to wind the extension 33A with a predetermined number of turns. In the present embodiment, the central portion CP has a length in which the wire is wound at least 3 turns as shown in fig. 14B. Therefore, the axis (center line) of the winding portion 33m of the extension portion 33A, which is a portion of the wire wound by a plurality of turns on the projection portion 72A, coincides with the projection shaft 72 AX. Therefore, a straight line along the axis of the winding portion 33m is inclined at a predetermined angle (for example, an angle of 30 degrees to 60 degrees) with respect to a straight line along the axis (optical axis JD) of the winding portion 13 of the coil 3. The same applies to the wound portion 33m of the extension portion 33B.

The lens holding member 2 is preferably configured such that a predetermined empty space is formed around the protrusion 72A. For example, the lens holding member 2 is formed so that no object is present in a predetermined range around the protruding portion 72A in order to secure a working space of a winding nozzle of an automatic winding machine. A space SP indicated by a dotted line in fig. 14B is an example of a working space of the winding nozzle. In the present embodiment, the space SP is a cylindrical space having the protruding axis 72AX as a central axis. This is because the automatic winding machine winds the wire around the protrusion 72A while rotating the winding nozzle around the protrusion shaft 72 AX. Specifically, as shown in fig. 14B, the shape and size of the lens holding member 2 are determined so that the winding portion 13, the protruding portion 2t, and the flange portion 52 of the coil 3 cannot be disposed in the space SP. This is because: when an object is placed in the space SP, the object comes into contact with the winding nozzle when the wire rod is wound around the protrusion 72A by the automatic winding machine.

Next, an effect of the protrusion 72 formed in the lens holding member 2 constituting the lens driving device 101 according to the embodiment of the present invention will be described with reference to fig. 16A to 16C. Fig. 16A to 16C are left side views of 3 kinds of projections. Specifically, fig. 16A is a left side view of the protrusion 172 formed on the lens holding member 102 as a reference example. Fig. 16B is a left side view of a projection 272 formed in the lens holding member 202 as another reference example. Fig. 16C is a left side view of the protrusion 72A formed in the lens holding member 2 according to the embodiment of the present invention, and corresponds to fig. 14B. For comparison, the winding portions 33m of the protruding portion 72A, the protruding portion 172, and the protruding portion 272 are formed so that the number of turns and the winding diameter are the same.

The projecting portion 172 formed in the lens holding member 102 as a reference example is formed to project from the lower surface of the flange portion 52 in the Z2 direction along the projecting axis 172X as shown in fig. 16A. The reason why the protruding portion 172 protrudes is: for example, the wire material constituting the coil 3 can be wound by 3 turns around the protruding portion 172, the lower plate spring 26 can be joined to the winding portion 33m with the joining material CA, and an object cannot be placed in the space SP, which is the working space of the winding nozzle. Further, the reason is also that it is desirable to provide a protruding portion for preventing the wire material wound around the protruding portion 172 from falling off the protruding portion 172. Therefore, the protrusion height of the protrusion 172 in the Z2 direction is the height Hr. When the projection height of the projection 172 in the Z2 direction is increased, the height of the lens holding member 2 in the Z axis direction is also increased, and further, the height of the lens driving device 101 in the Z axis direction is also increased. That is, the large projection height of the projection 172 in the Z2 direction hinders the miniaturization or the low height of the lens driving device 101.

The projection 272 formed in the lens holding member 202 as another reference example is formed to project from the side surface of the flange portion 52 in the Y1 direction along the projection axis 272X as shown in fig. 16B. The reason why the protruding portion 272 protrudes is the same as that in the case of fig. 16A. Further, the reason is also that it is desirable to dispose the protruding portion. Therefore, the protruding width of the protruding portion 272 from the end surface of the winding portion 13 in the Y1 direction is the width Wr. When the projecting width of the projecting portion 272 in the Y1 direction is large, the width of the lens holding member 2 in the Y axis direction is also large, and further the width of the lens driving device 101 in the Y axis direction is also large. That is, the large projection width of the projection 272 in the Y1 direction hinders the miniaturization of the lens driving device 101 and the enlargement of the lens diameter.

In contrast, as shown in fig. 16C, the projecting portion 72A formed in the lens holding member 2 according to the embodiment of the present invention is formed so as to project obliquely outward from the flange portion 52 along the projecting shaft 72 AX. The reason why the protruding portion 72A protrudes is the same as in the case of fig. 16A and 16B. Further, the reason is also that it is desirable to dispose the protruding portion. Therefore, the projection height of the projection 72A in the direction Z2 is the height Ht. However, height Ht is smaller than height Hr (see also fig. 16A) by Δ H. The projecting width of the projecting portion 72A from the end face of the winding portion 13 in the Y1 direction is a width Wt. However, the width Wt is smaller than the width Wr (see also fig. 16B) by Δ W.

As described above, in the lens driving device 101 according to the embodiment of the present invention, the protruding portion 72 protrudes obliquely outward, not in the direction parallel to the optical axis JD nor in the direction perpendicular to the optical axis JD. Therefore, the projecting width in the Y-axis direction and the projecting height in the Z-axis direction can be adjusted in a well-balanced manner while securing the space SP with respect to the projecting portion 72. As a result, the protruding portion 72 enables winding of the wire rod toward the protruding portion 72 by the automatic winding machine, and an increase in the size of the lens holding member 2 in the direction perpendicular to the optical axis JD can be suppressed, while enabling a reduction in the size of the lens holding member 2 in the direction of the optical axis JD. As a result, the protruding portion 72 contributes to miniaturization of the lens driving device 101.

As described above, the lens driving device 101 according to the embodiment of the present invention includes: a stationary-side member RG; a lens holding member 2 capable of holding a lens body; a plate spring 6 that supports the lens holding member 2 so as to be movable in the direction of the optical axis JD; a coil 3 held by the lens holding member 2; and a magnet 5 opposed to the coil 3. The leaf spring 6 includes an upper leaf spring 16 and a lower leaf spring 26. The lower leaf spring 26 includes a lower leaf spring 26A and a lower leaf spring 26B. The upper leaf spring 16 includes: an outer portion 16e as a fixed-side support portion fixed to the case 4 as the fixed-side member RG; and an inner portion 16i as a movable side support portion fixed to the lens holding member 2. The lower leaf spring 26A and the lower leaf spring 26B each include: an outer portion 26e as a fixed-side support portion fixed to base member 18 as fixed-side member RG; and an inner portion 26i as a movable side support portion fixed to the lens holding member 2. The coil 3 has: a winding portion 13 held by the lens holding member 2; and an extension 33 connected to the winding portion 13. The extension 33 is electrically connected to the lower leaf spring 26. The lens holding member 2 has a projection 72 around which the extension 33 is wound. Further, the protruding portion 72 protrudes obliquely outward with respect to the optical axis JD. The above configuration can obtain an effect that the amount of projection of the projection portion 72 in the optical axis JD direction can be suppressed, and further downsizing (dwarfing) of the lens driving apparatus 101 can be achieved.

Further, the configuration in which the protruding portion 72 extends obliquely outward has an advantage that the space SP, which is the working space of the winding nozzle, is easily secured, compared to the configuration in which the protruding portion extends in the direction parallel to the optical axis JD or in the direction perpendicular to the optical axis JD as shown in fig. 16A or 16B. Therefore, the above configuration can obtain an effect of suppressing the amount of projection of the projection 72 in the direction of the optical axis JD without adversely affecting other functional portions of the lens holding member 2 such as the projection 2t, the coil support portion 12j, and the flange portion 52.

A protruding portion 73 may be formed at the tip portion TP of the protruding portion 72. In this case, the extension 33 is wound on the side closer to the root portion BP of the protrusion 72 than the extension 73. Specifically, as shown in fig. 14B and 15B, the extension 33 is wound around the central portion CP located on the side closer to the base portion BP of the protrusion 72 than the protrusion 73 (the 1 st protrusion 73a and the 2 nd protrusion 73B). This configuration can obtain an effect of preventing the wire material wound around the protruding portion 72 from falling off from the protruding portion 72.

A1 st extension 73a and a2 nd extension 73b may be formed at a tip portion TP of the protrusion 72. In this case, the 1 st protruding part 73a may protrude perpendicularly to the protruding direction of the 2 nd protruding part 73 b. This structure can obtain an effect of more reliably preventing the wire material wound around the protruding portion 72 from falling off from the protruding portion 72 by cooperation of the 2 protruding portions. Further, the structure in which the 2 projecting portions each project in the die drawing direction of the die or in the direction perpendicular to the die drawing direction can obtain an effect that the structure of the die can be formed into a relatively simple structure.

The lens holding member 2 may have a flange portion 52 as a restricting portion that restricts movement of the winding portion 13 in the direction of the optical axis JD. In this case, the protruding portion 72 may constitute a part of the flange portion 52. For example, as shown in fig. 15A, the flat upper surface TS1 constituting the base portion BP of the projection 72B may be configured to support the winding portion 13 of the coil 3 together with the upper surface TS2 (see fig. 5A) of the flange portion 52. With this configuration, the protruding portion 72 can prevent the movement of the winding portion 13 in the Z2 direction along the optical axis together with the flange portion 52. Further, the protruding portion 72 can support the winding portion 13 together with the flange portion 52, and therefore the winding shape of the coil 3 can be stabilized. That is, the protruding portion 72 can prevent the winding shape of the coil 3 from being disturbed.

The protruding portion 72 preferably protrudes at an angle θ of 30 degrees or more and 60 degrees or less with respect to a plane perpendicular to the optical axis JD. In this case, the lens holding member 2 can adjust the projection width in the Y-axis direction and the projection height in the Z-axis direction in a well-balanced manner while securing, for example, a space SP which is a working space of the winding nozzle. Therefore, this structure can enable the winding of the wire rod toward the protruding portion 72 by the automatic winding machine, and can suppress an increase in the size of the lens holding member 2 in the direction perpendicular to the optical axis JD while enabling a reduction in the size of the lens holding member 2 in the direction of the optical axis JD. As a result, this structure contributes to miniaturization of the lens driving device 101.

The protrusion 72 may include: a1 st projection 72A around which one end of the coil 3 is wound; and a2 nd projecting portion 72B around which the other end of the coil 3 is wound. In this case, the 1 st protruding portion 72A and the 2 nd protruding portion 72B may be arranged at positions facing each other with the optical axis JD of the lens body interposed therebetween and protrude in directions away from each other. For example, as shown in fig. 6A, the protruding portion 72A is disposed on the Y1 side with respect to the optical axis JD, and the protruding portion 72B is disposed on the Y2 side with respect to the optical axis JD. Further, the protruding portion 72A and the protruding portion 72B are in a mutually plane-symmetric relationship with respect to an XZ plane including the optical axis JD. The protruding portions 72A and 72B are configured to protrude in directions away from each other in a bottom view, as indicated by arrows AR1 in fig. 6A. This configuration can obtain an effect of not being hindered by one of the protruding portions 72A and 72B when the wire material is wound around the other.

The fixed-side member RG may include a rectangular box-shaped case 4, the case 4 having a1 st side plate portion 4a1 as a pair of side plate portions; and a2 nd side plate portion 4a2 as another pair of side plate portions. For example, as shown in fig. 10A, the 1 st protruding portion 72A may be disposed to face one of the 2 nd side plate portions 4a2, and the 2 nd protruding portion 72B may be disposed to face the other of the 2 nd side plate portions 4a 2. Alternatively, the 1 st protruding portion 72A may be disposed so as to face one of the 1 st side plate portions 4a1, and the 2 nd protruding portion 72B may be disposed so as to face the other of the 1 st side plate portions 4a 1. Further, the magnet 5 may be disposed to face a corner of the case 4. For example, as shown in fig. 10B, the 4 magnets 5 may be disposed so as to face each of the corners located at the four corners of the housing 4. This configuration can improve the space efficiency inside the housing 4, and further, can realize further miniaturization of the lens driving device 101.

Next, the details of the upper leaf spring 16 will be described with reference to fig. 17. Fig. 17 is a plan view of the upper leaf spring 16, corresponding to fig. 11A.

The upper leaf spring 16 has 2 elastic arm portions 16g connecting the inner portion 16i and the outer portion 16 e. The 2 resilient arm portions 16g are the 1 st resilient arm portion 16g1 and the 2 nd resilient arm portion 16g 2.

In the present embodiment, the 1 st elastic arm portion 16g1 has a trifurcate shape. Specifically, the 1 st elastic arm portion 16g1 includes: a branch section BF; a1 st arm portion AM1 extending from the branch portion BF toward the 1 st end portion TA 1; a2 nd arm portion AM2 extending from the branch portion BF toward the 2 nd end portion TA 2; and a3 rd arm portion AM3 extending from the branch portion BF toward the 3 rd end portion TA 3. The same applies to the 2 nd elastic arm portion 16g 2. In fig. 17, for convenience, the positions of the branch portion BF, the 1 st end TA1, the 2 nd end TA2, the 3 rd end TA3, and the optical axis JD are shown by black circles.

The 1 st end TA1 of the 1 st resilient arm portion 16g1 is connected to one of the 4 corner portions 16b forming the outer portion 16e, i.e., the upper right corner portion 16 bTR. The 1 st end TA1 of the 2 nd resilient arm portion 16g2 is connected to the other 1 of the 4 corner portions 16b, i.e., the lower left corner portion 16 bBL.

The 2 nd end portion TA2 of the 1 st resilient arm portion 16g1 is connected to one of the 2 inner engagement portions 16c constituting the inner side portion 16i, i.e., the left inner engagement portion 16 cL. The 2 nd end portion TA2 of the 2 nd resilient arm portion 16g2 is connected to the other 1 of the 2 inner joint portions 16c, i.e., the right inner joint portion 16 cR.

The 3 rd end portion TA3 of the 1 st resilient arm portion 16g1 is connected to the right inner joint portion 16 cR. The 3 rd end portion TA3 of the 2 nd elastic arm portion 16g2 is connected to the left inner joint part 16 cL.

2 of the 4 corner portions 16b constituting the outer side portion 16e, that is, the lower right corner portion 16bBR and the upper left corner portion 16bTL are not connected to any of the 1 st elastic arm portion 16g1 and the 2 nd elastic arm portion 16g 2.

The 1 st elastic arm portion 16g1 has an angle α formed between a line segment L0 connecting the optical axis JD and the branch portion BF and a line segment L1 connecting the optical axis JD and the 1 st end TA 1. Similarly, an angle β is formed between a line segment L2 connecting the optical axis JD and the 2 nd end TA2 and a line segment L0, and an angle γ is formed between a line segment L3 connecting the optical axis JD and the 3 rd end TA3 and a line segment L0. The maximum value of the angles formed between any 2 of the 4 line segments L0 to L3 is the angle formed between the line segment L2 and the line segment L3 (═ β + γ). The same applies to the 2 nd elastic arm portion 16g 2.

In this way, in the present embodiment, the elastic arm portion 16g is configured to have an angle larger than the angle β. That is, the 1 st arm AM1 and the 2 nd arm AM2 are configured to extend from the branch portion BF in the 1 st circumferential direction (counterclockwise direction) of a circle centered on the optical axis JD, and the 3 rd arm AM3 is configured to extend from the branch portion BF in the 2 nd circumferential direction (clockwise direction) opposite to the 1 st circumferential direction. The 2 nd arm AM2 is longer than the 1 st arm AM 1. According to this structure, the elastic arm portion 16g can achieve an appropriate spring constant in the direction of the optical axis JD while achieving an appropriate spring stiffness in the direction perpendicular to the optical axis JD. The appropriate spring constant is determined by the thrust generated by the drive mechanism MK, the weight of the movable-side members such as the lens holding member 2 and the coil 3, and the like.

Next, details of the lower leaf spring 26 will be described with reference to fig. 18. Fig. 18 is a bottom view of the lower leaf spring 26, corresponding to fig. 11B.

The lower leaf spring 26 includes a lower leaf spring 26A and a lower leaf spring 26B. The lower leaf spring 26A has an elastic arm portion 26Ag connecting the inner portion 26Ai, the 1 st outer joint portion 26d1 constituting the outer portion 26Ae, and the 2 nd outer joint portion 26d2 constituting the outer portion 26 Ae. The lower leaf spring 26B has an elastic arm portion 26Bg that connects the inner portion 26Bi, the 1 st outer engaging portion 26d1 constituting the outer portion 26Be, and the 2 nd outer engaging portion 26d2 constituting the outer portion 26 Be.

In the present embodiment, the elastic arm portion 26Ag of the lower leaf spring 26A has a three-pronged shape. Specifically, the elastic arm portion 26Ag has: a branch section BF; a1 st arm portion AM1 extending from the branch portion BF toward the 1 st end portion TA 1; a2 nd arm portion AM2 extending from the branch portion BF toward the 2 nd end portion TA 2; and a3 rd arm portion AM3 extending from the branch portion BF toward the 3 rd end portion TA 3. The same applies to the elastic arm portion 26Bg of the lower leaf spring 26B. In fig. 18, for convenience, the positions of the branch portion BF, the 1 st end TA1, the 2 nd end TA2, the 3 rd end TA3, and the optical axis JD are shown by black circles.

The 1 st end portion TA1 of the elastic arm portion 26Ag is connected to the 1 st outer joint portion 26d1 constituting the outer side portion 26 Ae. The 1 st end portion TA1 of the elastic arm portion 26Bg is connected to the 2 nd outside engaging portion 26d2 constituting the outside portion 26 Be.

The 2 nd end TA2 of resilient arm portion 26Ag is connected to inner portion 26 Ai. The 2 nd end portion TA2 of the resilient arm portion 26Bg is connected to the inside portion 26 Bi.

The 3 rd end portion TA3 of the elastic arm portion 26Ag is connected to the 2 nd outer joint portion 26d2 constituting the outer side portion 26 Ae. The 3 rd end portion TA3 of the elastic arm portion 26Bg is connected to the 1 st outer engaging portion 26d1 constituting the outer side portion 26 Be.

The elastic arm portion 26Ag forms an angle α between a line segment L0 connecting the optical axis JD and the branch portion BF and a line segment L1 connecting the optical axis JD and the 1 st end TA 1. Similarly, an angle β is formed between a line segment L2 connecting the optical axis JD and the 2 nd end TA2 and a line segment L0, and an angle γ is formed between a line segment L3 connecting the optical axis JD and the 3 rd end TA3 and a line segment L0. The maximum value of the angles formed between any 2 of the 4 line segments L0 to L3 is the angle formed between the line segment L2 and the line segment L3 (═ β + γ). The same applies to the elastic arm portion 26 Bg.

In this way, in the present embodiment, the elastic arm portion 26g is configured to have an angle larger than the angle β. That is, the 1 st arm AM1 and the 2 nd arm AM2 are configured to extend from the branch portion BF in the 1 st circumferential direction of a circle centered on the optical axis JD, and the 3 rd arm AM3 is configured to extend from the branch portion BF in the 2 nd circumferential direction opposite to the 1 st circumferential direction. The 2 nd arm AM2 is longer than the 1 st arm AM 1. According to this structure, the elastic arm portion 26g can achieve an appropriate spring constant in the direction of the optical axis JD while achieving an appropriate spring stiffness in the direction perpendicular to the optical axis JD.

As described above, the lens driving device 101 according to the embodiment of the present invention includes: a stationary-side member RG; a lens holding member 2 capable of holding a lens body; a plate spring 6 that supports the lens holding member 2 so as to be movable in the direction of the optical axis JD; a coil 3 held by the lens holding member 2; and a magnet 5 opposed to the coil 3. Further, the plate spring 6 includes: an upper plate spring 16 disposed on the upper side (Z1 side) of the lens holding member 2; and a lower plate spring 26 disposed below (on the Z2 side) the lens holding member 2. At least one of the upper plate spring 16 and the lower plate spring 26 connects the fixed-side member RG to the lens holding member 2 by 2 elastic arm portions. For example, the upper plate spring 16 may connect the housing 4 as the fixed-side member RG and the lens holding member 2 by the 1 st elastic arm portion 16g1 and the 2 nd elastic arm portion 16g 2. Specifically, as shown in fig. 17, the inner portion 16i may be connected to the outer portion 16e with the 1 st resilient arm portion 16g1 and the 2 nd resilient arm portion 16g 2. The lower leaf spring 26 may connect the base member 18 as the fixed-side member RG and the lens holding member 2 by the elastic arm portions 26Ag of the lower leaf spring 26A and the elastic arm portions 26Bg of the lower leaf spring 26B. Specifically, as shown in fig. 18, the inner portion 26Ai of the lower plate spring 26A may Be connected to the 2 outer portions 26Ae of the lower plate spring 26A by the elastic arm portions 26Ag, and the inner portion 26Bi of the lower plate spring 26B may Be connected to the 2 outer portions 26Be of the lower plate spring 26B by the elastic arm portions 26 Bg.

By configuring the fixed-side member RG to be continuous with the lens holding member 2 by 2 elastic arm portions, the lens driving device 101 can extend the 2 elastic arm portions as compared with the case where the number of elastic arm portions is 3 or more. This is because a space for accommodating the elastic arm portion is easily secured. As a result, the lens driving device 101 can achieve an appropriate spring constant even when it is downsized, that is, even when a space for accommodating 3 or more elastic arm portions having a desired length cannot be secured. This means that miniaturization can be appropriately achieved. Specifically, when the weight of the movable member such as the lens holding member 2 and the coil 3 is reduced, or when the driving force (thrust force) that can be generated by the driving mechanism MK is reduced due to the downsizing of the magnet 5, the spring constant can be appropriately reduced. In addition, the spring constant includes a spring constant in the direction of the optical axis JD and a spring constant in the direction perpendicular to the optical axis JD.

The 1 st elastic arm portion 16g1 may be configured to include: 1 st end portion TA1 connected to case 4 as stationary-side member RG via outer portion 16 e; a2 nd end portion TA2 connected to the lens holding member 2 via the inside portion 16 i; and a3 rd end portion TA3 connected to the lens holding member 2 via the inner portion 16 i. Specifically, as shown in fig. 17, the 1 st elastic arm portion 16g1 may be configured to include: end 1 TA1 connected to upper right corner portion 16 bTR; a2 nd end portion TA2 connected to the left inner joint portion 16 cL; and a3 rd end portion TA3 connected to the right inner engaging portion 16 cR.

The 2 nd elastic arm portion 16g2 may be configured to have: 1 st end portion TA1 connected to case 4 as stationary-side member RG via outer portion 16 e; a2 nd end portion TA2 connected to the lens holding member 2 via the inside portion 16 i; and a3 rd end portion TA3 connected to the lens holding member 2 via the inner portion 16 i. Specifically, as shown in fig. 17, the 2 nd elastic arm portion 16g2 may be configured to include: a1 st end TA1 connected to the lower left corner portion 16 bBL; a2 nd end portion TA2 connected to the right inner engaging portion 16 cR; and a3 rd end portion TA3 connected to the left inner joint portion 16 cL.

The elastic arm portion 26Ag may be configured to include: 1 st end portion TA1 connected to base member 18 as fixed-side member RG; a2 nd end TA2 connected to the lens holding member 2; and a3 rd end TA3 connected to base member 18. Specifically, as shown in fig. 18, the elastic arm portion 26Ag may be configured to include: a1 st end TA1 connected to the 1 st outboard engaging portion 26d 1; a2 nd end TA2 connected to the inner joint portion 26 c; and a3 rd end TA3 connected with the 2 nd outer engaging portion 26d 2.

The elastic arm portion 26Bg may be configured to have: 1 st end portion TA1 connected to base member 18 as fixed-side member RG; a2 nd end TA2 connected to the lens holding member 2; and a3 rd end TA3 connected to base member 18. Specifically, as shown in fig. 18, the elastic arm portion 26Bg may be configured to include: a1 st end TA1 connected to the 2 nd outer engaging portion 26d 2; a2 nd end TA2 connected to the inner joint portion 26 c; and a3 rd end TA3 connected with the 1 st outboard engaging portion 26d 1.

The lower plate spring 26 is formed of a conductive member, and can be divided into: a lower plate spring 26A as a1 st spring portion; and a lower plate spring 26B as a2 nd spring portion. In this case, it may be formed that: the lower plate spring 26A may be electrically connected to one end of the coil 3, and the lower plate spring 26B may be electrically connected to the other end of the coil 3. Specifically, as shown in fig. 18, the lower leaf spring 26A is welded to the metal member 7 at the 1 st outer joining portion 26d1, and the web portion 26h of the inner portion 26Ai is joined to the coil 3 by the joining material CA. Therefore, the current flowing from the terminal 7A to the terminal 7B flows from the metal member 7 to the coil 3 through, for example, the 1 st end TA1, the 1 st arm AM1, the branch portion BF, the 2 nd arm AM2, and the 2 nd end TA 2. As shown in fig. 18, the lower leaf spring 26B is welded to the metal member 7 at the 1 st outer joining portion 26d1, and the web portion 26h of the inner portion 26Bi is joined to the coil 3 with the joining material CA. Therefore, the current flowing from the terminal 7A to the terminal 7B flows from the coil 3 to the metal member 7 through, for example, the 2 nd end portion TA2, the 2 nd arm portion AM2, the branch portion BF, the 3 rd arm portion AM3, and the 3 rd end portion TA 3. With this configuration, the lens driving device 101 can easily form a current path from the metal member 7 to the coil 3.

The elastic arm portion 16g may have, for example: a branch section BF; a1 st arm portion AM1 extending from the branch portion BF and connected to the case 4 as the fixed-side member RG through the outer portion 16 e; a2 nd arm portion AM2 extending from the branch portion BF in the same direction as the 1 st arm portion AM1 (for example, counterclockwise in fig. 17) and connected to the lens holding member 2 via the inside portion 16 i; and a3 rd arm portion AM3 extending from the branch portion BF in a direction different from the 1 st arm portion AM1 and the 2 nd arm portion AM2 (for example, clockwise in fig. 17). In this case, the 3 rd arm portion AM3 may be configured to: the 1 st arm portion AM1 is connected to the housing 4 via the outer portion 16e when being longer than the 2 nd arm portion AM2, and is connected to the lens holding member 2 via the inner portion 16i when the 1 st arm portion AM1 is shorter than the 2 nd arm portion AM 2. For example, as shown in fig. 17, in the case where the 1 st arm portion AM1 is shorter than the 2 nd arm portion AM2, the 3 rd arm portion AM3 may be configured to be connected to the lens holding member 2 via the inside portion 16 i. In this case, the rigidity by the 2 nd arm portion AM2 becomes lower in the lateral direction (Y-axis direction). However, since the 3 rd arm portion AM3 extending in the Y-axis direction is connected to the lens holding member 2, the decrease in the lateral (Y-axis direction) rigidity by the 2 nd arm portion AM2 is complemented by the rigidity by the 3 rd arm portion AM 3. With this structure, the elastic arm portion 16g can achieve a desired rigidity. As a result, the higher-order resonance frequency can be increased. Further, the lens holding member 2 can be prevented from being excessively moved in the direction perpendicular to the optical axis JD.

The stationary-side member RG may include a rectangular box-shaped case 4, and the case 4 has a1 st side plate portion 4a1 and a2 nd side plate portion 4a2 perpendicular to the 1 st side plate portion 4a 1. In this case, the elastic arm portion may have a portion facing at least one of the 1 st side plate portion 4a1 and the 2 nd side plate portion 4a 2.

For example, it can be formed as: as shown in fig. 17, each of the 1 st elastic arm portion 16g1 and the 2 nd elastic arm portion 16g2 of the upper leaf spring 16 includes: a3 rd arm portion AM3 which is a portion opposed to the 1 st side plate portion 4a 1; and a2 nd arm portion AM2 which is a portion opposed to the 2 nd side plate portion 4a 2. In this way, since the elastic arm portion 16g includes portions facing the 1 st side plate portion 4a1 and the 2 nd side plate portion 4a2 that are substantially orthogonal to each other, the rigidity in the direction perpendicular to the optical axis (the X-axis direction and the Y-axis direction) can be improved.

And, it can be formed as: as shown in fig. 18, each of the elastic arm portion 26Ag of the lower leaf spring 26A and the elastic arm portion 26Bg of the lower leaf spring 26B includes: the 1 st arm portion AM1 and the 3 rd arm portion AM3, which are portions facing the 1 st side plate portion 4a 1. In this way, the elastic arm portion 26g includes a portion facing the 1 st side plate portion 4a1, and therefore the rigidity in the Y axis direction can be improved.

The elastic arm portion 26g may be configured to include: a branch section BF; 1 st end portion TA1 connected to base member 18 as fixed-side member RG via outer portion 26 e; a2 nd end portion TA2 connected to the lens holding member 2 via the inside portion 26 i; and a3 rd end portion TA3 connected to the base member 18 or the lens holding member 2. In this case, the maximum value of the angle around the optical axis JD formed by the line segment L0 connecting the optical axis JD of the lens body and the branch portion BF, and the line segments L1, L2, or L3 connecting the optical axis JD and the 1 st end TA1, the 2 nd end TA2, or the 3 rd end TA3 is preferably smaller than the maximum value of the angle around the optical axis JD formed by 2 line segments connecting the optical axis JD and each of the 1 st end TA1, the 2 nd end TA2, and the 3 rd end TA 3. For example, as shown in fig. 18, angles α, β, γ formed by a line segment L0 connecting the optical axis JD of the lens body and the branch portion BF and 3 line segments L1 to L3 connecting the optical axis JD and each of the 1 st end TA1, the 2 nd end TA2, and the 3 rd end TA3 are all smaller than the maximum value of the angles formed by 2 line segments connecting the optical axis JD and each of the 2 st end TA1, the 2 nd end TA2, and the 3 rd end TA3, that is, the angle. According to this structure, the elastic arm portion 26g can achieve an appropriate spring constant in the direction of the optical axis JD while achieving an appropriate spring stiffness in the direction perpendicular to the optical axis JD.

The preferred embodiments of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiments. The above-described embodiments can be variously modified and replaced without departing from the scope of the present invention. The features described with reference to the above embodiments may be combined as appropriate as long as there is no technical contradiction.

For example, in the above-described embodiment, the lens holding member 2 is supported by the fixed-side member RG via the upper plate spring 16 having 2 elastic arm portions 16g and the lower plate spring 26 having 2 elastic arm portions 26 g. However, the lens holding member 2 may be supported by the fixed-side member RG via an upper plate spring 16 having 3 or more elastic arm portions 16g and a lower plate spring 26 having 2 elastic arm portions 26 g. Alternatively, the lens holding member 2 may be supported by the fixed-side member RG via an upper plate spring 16 having 2 elastic arm portions 16g and a lower plate spring 26 having 3 or more elastic arm portions 26 g.

In the above embodiment, the lower plate spring 26A is electrically connected to the extending portion 33B, and the lower plate spring 26B is electrically connected to the extending portion 33A, but the present invention is not limited to this configuration. For example, in a lens driving device with a camera shake correction function, the upper plate spring 16 may be divided into 2 pieces, one of which is electrically connected to the winding start portion of the coil and the other of which is electrically connected to the winding end portion of the coil. The lens driving device with the camera shake correction function has a magnet holder for holding the magnet 5. The magnet holder is different from the lens holder 2, which is a movable member that moves in the direction of the optical axis JD, and constitutes a fixed member that cannot move in the direction of the optical axis JD.

The present application claims priority based on the japanese patent application No. 2018-056826 filed on 3/23/2018, the entire contents of which are incorporated herein by reference.

Description of the reference numerals

2 · lens holding member; 2t · projecting part; 3. coil; 4. shell; 4A. outer wall portion; 4a1 · 1 st side panel portion; 4a2 · 2 nd side plate portion; 4B · upper surface part; 4R · bolster; 4s · receiving section; 5. magnet; 6. leaf spring; 7. metal parts; 7A, 7B. terminal; 7D · connecting member; 7A1, 7B 1. part exposed; 12. cylindrical portion; 12d · pedestal part; 12dh · divot; 12 h. eave; 12j · coil support; 13. coil; 16. upper leaf spring; 16b · angle part; 16e · outer portion; 16 g. elastic arm portion; 16i · inner part; 16r · bridge of stack; 18. a base member; 18F · flange portion; 18k · open; 18t · projecting portion; 18W · sidewall face; 26. 26A, 26B. lower leaf spring; 26c · inner junction portion; 26d · outer junction portion; 26e · outer portion; 26 g. resilient arm portion; 26h · web portion; 26i · inner part; 26p · No. 1 connecting part; 26t · through part; 33. 33A, 33B. an extension; 33 c.a.connection; 33m · winding; 52. flange portion; 72. 72A, 72B. the projection; 101. lens driving device; CA. bonding material; JD. optical axis; MK. a drive mechanism; RG. stationary side components.

Claims (7)

1. A lens driving device is provided with:

a stationary-side member;

a lens holding member capable of holding a lens body;

a plate spring that supports the lens holding member so as to be movable in the direction of the optical axis;

a coil held by the lens holding member; and

a magnet opposed to the coil,

wherein the content of the first and second substances,

the plate spring includes: an upper plate spring disposed above the lens holding member; and a lower plate spring disposed below the lens holding member,

at least one of the upper plate spring and the lower plate spring connects the fixed-side member and the lens holding member with 2 elastic arm portions.

2. The lens driving device according to claim 1,

the elastic arm portion includes: a1 st end portion connected to the fixed-side member; a2 nd end portion connected to the lens holding member; and a3 rd end portion connected to the fixing-side member or the lens holding member.

3. The lens driving device according to claim 1 or 2,

the lower plate spring is formed of a conductive member and is divided into a1 st spring portion and a2 nd spring portion,

the 1 st spring part is electrically connected to one end of the coil,

the 2 nd spring part is electrically connected to the other end of the coil.

4. The lens driving device according to any one of claims 1 to 3,

the elastic arm portion includes:

a branching section;

a1 st arm portion extending from the branch portion and connected to the fixed-side member;

a2 nd arm portion extending from the branch portion and connected to the lens holding member; and

a3 rd arm part extending from the branch part,

the 3 rd arm portion is configured to:

when the 1 st arm part is longer than the 2 nd arm part,

and the 1 st arm part is shorter than the 2 nd arm part, and is connected with the lens holding member.

5. The lens driving device according to any one of claims 1 to 4,

the fixed-side member includes a rectangular box-shaped case having a1 st side plate portion and a2 nd side plate portion perpendicular to the 1 st side plate portion,

the elastic arm portion has a portion facing at least one of the 1 st side plate portion and the 2 nd side plate portion.

6. The lens driving device according to any one of claims 1 to 5,

the elastic arm portion includes: a branching section; a1 st end portion connected to the fixed-side member; a2 nd end portion connected to the lens holding member; and a3 rd end portion connected to the fixing-side member or the lens holding member,

the maximum value of angles around the optical axis formed by a line segment connecting the optical axis of the lens body and the branch portion and a line segment connecting the optical axis and the 1 st end portion, the 2 nd end portion or the 3 rd end portion is smaller than the maximum value of angles around the optical axis formed by the optical axis and 2 of the 1 st end portion, the 2 nd end portion and the 3 rd end portion.

7. A camera module having:

the lens driving device according to any one of claims 1 to 6;

the lens body; and

and an imaging element facing the lens body.

Images