JP2012255972A - Lens drive device, autofocus camera, and mobile terminal with camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device capable of preventing foreign materials from entering an inner portion of the lens drive device from the outside, an autofocus camera, and a mobile terminal with a camera.SOLUTION: A lens drive device 1 comprises: a lens supporting body 5 for supporting a lens on its inner periphery; a coil 19 arranged on an outer periphery of the lens supporting body 5; an annular yoke 3 with the lens support 5 movably arranged on its inner peripheral side; a magnet 13 mounted on the yoke 3 and arranged so as to face the coil 19; a rear side spring 11 electrically connected to the coil 19 and movably holding the lens supporting body 5; and a base 8 arranged on one end side of the yoke 3 in the optical axis direction and holding the rear side spring 11. A projection wall 8c facing the inner peripheral surface of the outer peripheral side wall 3a of the yoke 3 is formed on the base 8.

Description

The present invention relates to a lens driving device, an autofocus camera, and a mobile terminal with a camera.
A mobile terminal means a mobile phone, a personal digital assistant (PDA), a notebook computer, or the like.

In Patent Document 1, a base is provided on the image side of a moving body provided with a lens, and a case that covers the moving body is attached to the base, and an opening for receiving light incident through the lens by an imaging device. There is disclosed a lens driving device in which a concave portion for dust storage that is recessed toward the image side is formed around the opening. According to the technique disclosed in Patent Document 1, dust can be captured and held in the dust storage recess, and therefore, dust can be prevented from passing through the opening of the base and adhering to the image sensor.
Patent Document 2 discloses a lens driving device that houses a lens holder that holds a lens and a lens holder, and a protrusion that surrounds the entire periphery of at least one of the openings on one of the housing portions attached to the base. It is disclosed. According to the technique of Patent Document 2, it is possible to prevent foreign matter from entering the lens driving device from between the lens holder and the housing portion.
Patent Document 3 includes a moving body that holds a lens, a support that supports the moving body, and a yoke that is disposed on the inner peripheral side and attached to the support. A lens driving device is disclosed in which an opening for allowing the reflected light to enter the image sensor is formed, and a protrusion protruding toward the moving body is formed at the periphery of the opening. According to the technique of this Patent Document 3, even when sliding powder is generated during production and assembly and falls on the support, the sliding powder is blocked by the convex portion and prevented from falling from the opening and adhering to the image sensor. it can.

JP 2010-190923 A JP 2009-251517 A JP 2009-139492 A

Incidentally, foreign matter inside the lens driving device may enter from a portion where the yoke and the base facing the outside of the lens driving device are joined.
However, in the techniques of Patent Documents 1, 2, and 3, even if the foreign matter that has entered the lens driving device can be prevented from adhering to the image pickup device, the yoke or base facing the outside of the lens driving device can be prevented. Since it does not have a structure for blocking the entry of foreign matter, it cannot be prevented that foreign matter enters the inside from the outside of the lens driving device.

  Therefore, an object of the present invention is to provide a lens driving device, an autofocus camera, and a camera-equipped mobile terminal that can prevent foreign matters from entering the inside from the outside.

  According to the first aspect of the present invention, there is provided a lens support for supporting the lens on the inner periphery, a coil provided on the outer periphery of the lens support, and an annular yoke in which the lens support is movably disposed on the inner periphery. A magnet attached to the yoke and arranged to face the coil, a spring electrically connected to the coil and movably holding the lens support, and arranged on one side in the optical axis direction of the yoke And a base that holds the spring, and moves the lens support back and forth along the optical axis direction of the lens by electromagnetic force generated by energizing the coil from the spring. A protruding wall facing the inner peripheral surface of the outer peripheral side wall is formed at a position where the inner peripheral surface of the outer peripheral side wall is disposed.

  According to a second aspect of the present invention, in the first aspect of the present invention, the base has a quadrangular shape as viewed from the front side in the optical axis direction, the spring is an annular leaf spring, and the lens support. An inner peripheral side portion attached to the base, an outer peripheral side portion attached to the base, and an arm portion that connects each inner peripheral side portion and the outer peripheral side portion and is elastically deformable. The outer peripheral side portions are adjacent to each other of the base. It has a long side portion that extends from one corner portion to the other corner portion and is disposed inside the protruding wall.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the base is formed with a fitting portion that is fitted to the end of the spring.

  According to a fourth aspect of the present invention, there is provided an autofocus camera comprising the lens driving device according to any one of the first to third aspects.

  A fifth aspect of the present invention is a camera-equipped mobile phone in which the autofocus camera according to the fourth aspect is mounted.

  According to the first aspect of the present invention, since the base is formed with the protruding wall facing the inner peripheral surface of the outer peripheral side wall of the yoke, when the yoke is attached to the base, the protruding wall is formed on the inner peripheral surface of the yoke. Opposite. Thereby, even if the foreign matter outside the lens driving device enters the portion where the base and the yoke are joined, the foreign material is blocked by the protruding wall, so that the foreign matter can be prevented from entering the inside from the outside of the lens driving device.

  According to the second aspect of the present invention, the effect of the first aspect is achieved and the long side portion of the spring is disposed inside the protruding wall, so that the long side portion of the spring is a gap between the base and the yoke. Can be prevented from protruding to the outside and coming into contact with other parts and short-circuiting.

  According to the invention described in claim 3, since the fitting portion that fits the end portion of the spring is formed in the base while having the function and effect described in claim 1 or 2, the end portion of the spring is connected to the base. It can be prevented from projecting to the outside through the gap with the yoke and coming into contact with other parts and short-circuiting.

  According to invention of Claim 4, the auto-focus camera which has the effect as described in any one of Claims 1-3 can be provided.

  According to invention of Claim 5, the mobile terminal with a camera which has the effect of Claim 4 can be provided.

It is a perspective view which extracts and shows a part of lens drive device concerning an embodiment. It is a top view which extracts and shows a part of lens drive device concerning an embodiment. It is BB sectional drawing shown in FIG. It is CC sectional drawing shown in FIG. It is a disassembled perspective view of the lens drive device concerning an embodiment. It is AA sectional drawing shown in FIG. It is a perspective view which shows the general appearance of the lens drive device which concerns on embodiment.

  Embodiments of the present invention will be described below in detail with reference to FIGS. A lens driving device 1 according to the present embodiment is a lens driving device for an autofocus camera incorporated in a mobile phone.

  As shown in FIG. 5, the lens driving device 1 is disposed on an annular yoke 3, a lens support 5, a front spring 9 disposed on the front side of the yoke 3 in the optical axis direction, and a front side of the front spring 9. Frame 7 and a base 8 and a rear spring 11 disposed on the rear side of the yoke 3, and a rear spacer 15 is disposed between the rear spring 11 and the yoke 3.

  The yoke 3 has a quadrilateral outer periphery when viewed from the front side and a circular inner periphery when viewed from the front, and the outer peripheral side wall 3a, the inner peripheral side wall 3b, and the outer peripheral side wall 3a and the inner peripheral side wall 3b are spaced apart. The outer peripheral side wall 3a, the inner peripheral side wall 3b, and the connecting wall 3c have a U-shaped cross section. On the inner peripheral side wall 3b, a cut portion 12 is formed from the rear end toward the front. The cut portions 12 are arranged at equal intervals in the circumferential direction. In the present embodiment, the cut portions 12 are provided at positions corresponding to between the adjacent corner portions 14 (side portions) on the outer peripheral side wall 3a having a rectangular shape in plan view. It is.

  At each corner 14 of the yoke 3, a magnet 13 is fixed to the inner peripheral surface of the outer peripheral side wall 3a. The magnet 13 is provided in the corner portion 14 and is not located at a position corresponding to the cutout portion 12 formed in the inner peripheral side wall 3b.

  The lens support 5 has a substantially cylindrical shape. A lens (not shown) is attached to the inner periphery of the lens support 5 so that the inner periphery of the yoke 3 can be moved in the optical axis direction. An annular coil 19 is fixed to the outer periphery of the lens support 5.

  As shown in FIG. 6, the coil 19 is disposed between the outer peripheral side wall 3 a and the inner peripheral side wall 3 b of the yoke 3, but the corner portion 14 where the magnet 13 is located is located between the magnet 13 and the inner peripheral side wall 3 b. The lens support 5 moves in the front-rear direction along the yoke 3.

  As shown in FIG. 5, the front spring 9 is an annular leaf spring, and is provided with an inner peripheral side portion 9a and an outer peripheral side portion 9b. The inner peripheral side portion 9a is attached to the lens support 5 and has an outer periphery. The side portion 9 b is sandwiched and fixed between the yoke 3 and the frame 7. The inner peripheral side portion 9a and the outer peripheral side portion 9b are connected by an elastically deformable arm portion 9c.

The base 8 is made of an insulative resin material having a quadrangular plane as viewed from the front side in the optical axis direction and having a through hole in the center. On the outer periphery of the base 8, leg portions 8 a are erected at the respective corners, and are fitted and fixed to the leg portions 7 a of the frame 7. In the rectangular outer peripheral surface of the base 8, two metal terminals 33 and 35 are arranged adjacent to each other on one side surface, and a fitting portion 8 b into which the end portion of the rear spring 11 is fitted is formed. .
As shown in FIG. 3, the fitting portion 8b is formed with a groove portion 80b into which the end portion of the rear spring 11 is fitted. The end of the rear spring 11 is fitted into the groove 80b, and the rear spacer 15 and the yoke 3 are arranged in this order from the front side.
As shown in FIG. 5, the base 8 is formed with a protruding wall 8 c that is opposed over substantially the entire circumference of the inner peripheral surface of the outer peripheral side wall 3 a of the yoke 3.

  Although the rear spring 11 is an annular leaf spring as a whole, in the present embodiment, the rear spring 11 is composed of a first side portion 20 and a second side portion 22 which are separated into left and right. A part of each outer peripheral side portion 11b of the rear spring 11 is sandwiched between the base 8 and the yoke 3 together with the rear spacer 15 which is an insulator, and the rear spacer 15 includes the rear spring 11 and the yoke 3. The electrical insulation between is intended. Each inner peripheral side portion 11 a is attached to the rear end of the lens support 5. Each inner peripheral side portion 11a and outer peripheral side portion 11b of the rear spring 11 are connected by an elastically deformable arm portion 11c.

As shown in FIG. 1 and FIG. 2, each outer peripheral side portion 11 b has a long side portion 110 b extending from one corner portion adjacent to the other corner portion of the base 8 and one end side of the long side portion 110 b. A short side portion 111b shorter than the long side portion 110b extending in a direction orthogonal to the long side portion 110b, and a connecting side portion 112b extending in a direction orthogonal to the long side portion 110b on the other end side of the long side portion 110b; Have. The connection side portions 112b of the one side portion 20 and the other side portion 22 are disposed at positions adjacent to each other. Metal terminals 33 and 35 (see FIG. 5) are connected to each connection side 112b.
As shown in FIG. 4, the long side portion 110 b is disposed inside the protruding wall 8 c of the base 8, and is not sandwiched between the base 8 and the yoke 3 together with the rear spacer 15.
As shown in FIG. 2, the short side portion 111b and the connection side portion 112b are disposed outside the protruding wall 8c. Further, as shown in FIG. 3, the connection side portion 112 b is fitted into the fitting portion 8 b of the base 8 and is sandwiched between the base 8 and the yoke 3 together with the rear spacer 15.

  Although not shown, one side 20 of the rear spring 11 is connected to one end of the coil 19, and the other side 22 of the rear spring 11 is connected to the other end of the coil 19.

Next, assembly, operation, and effect of the lens driving device 1 according to the embodiment will be described.
In assembling the lens driving device 1, first, the rear spring 11 is fixed to the resin-molded base 8.
Specifically, as shown in FIGS. 1 and 2, the long side portions 110b of the respective outer peripheral side portions 11b of the rear spring 11 are arranged inside the protruding wall 8c of the base 8, and the short side portions 111b and the connecting side portions are arranged. 112b is arranged outside the protruding wall 8c, and the end of the connecting side portion 112b is fitted into the fitting portion 8b of the base 8.
Next, as shown in FIG. 5, the rear spacer is connected to the base 8 to which the metal terminals 33 and 35 are respectively connected to the connection side portions 112b of the rear spring 11 and the outer peripheral side portion 11b of the rear spring 11 is fixed. 15. The lens support 5 with the coil 19 fixed to the outer peripheral surface, the yoke 3 with the magnet 13 fixed to the inner peripheral side, the front spring 9 and the frame 7 are assembled and fixed in this order.

Then, one end of the coil 19 is connected to the inner peripheral side portion 11 a of the one side portion 20 constituting the rear spring 11 with an adhesive or solder, and the other end portion 22 of the coil 19 is constituted of the rear spring 11. The inner peripheral side portion 11a is connected with an adhesive or solder.
The lens driving device 1 according to the present embodiment is mounted on a mobile phone, and the metal terminal 33 and the metal terminal 35 are used as power supply terminals, and the rear side end portion is a power supply terminal (not shown) of a circuit board (not shown). For example, it is connected by soldering.

When the lens driving device 1 is driven, the metal terminal 33 connected to the power terminal of the substrate is connected to the one side 20 of the rear spring 11, the coil 19, the other side 22 of the rear spring 11, and the power terminal of the circuit board. A direct current flows through the formed metal terminal 35. At that time, since the base 8 is made of an insulator and the metal terminal 33 and the metal terminal 35 are arranged separately, current leaks between the metal terminal 33 and the metal terminal 35 via the base 8. Not flowing.
When the coil 19 is energized in this way, the lens support 5 moves against the urging force of the front spring 9 and the rear spring 11 by the electromagnetic force acting on the coil 19, and the front spring 9 and the rear spring 11 are moved. Stops at a position where the force balances with.

  According to the embodiment of the present invention, since the base 8 is formed with the protruding wall 8c facing the inner peripheral surface of the outer peripheral side wall 3a of the yoke 3, when the yoke 3 is attached to the base 8, the yoke 3 The protruding wall 8c faces the inner peripheral surface. Thus, foreign matter outside the lens driving device is blocked by the protruding wall 8c even if it enters the portion where the base 8 and the yoke 3 are joined, so that foreign matter can enter the lens driving device 1 from the outside. Can be prevented.

  Since the long side portion 110b of the rear side spring 11 is disposed inside the protruding wall 8c, the long side portion 110b of the rear side spring 11 protrudes to the outside through the gap between the base 8 and the yoke 3, and contacts other parts to cause a short circuit. Can be prevented.

  Since the base 8 is formed with the fitting portion 8b that fits with the connection side 112b of the one side 20 and the other side 22 of the rear spring 11, the connection side 112b of the rear spring 11 is connected to the base 8 and the rear side. It can be prevented from projecting to the outside through the gap with the spacer 15 and coming into contact with other parts and short-circuiting.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, in the above-described embodiment, the rear spring 11 has only the long side portion 110b disposed inside the protruding wall 8c of the base 8, but is not limited thereto, and the short side portion 111b and the connecting side portion 112b also protrude. You may arrange | position inside the wall 8c.
In the above-described embodiment, the connection side portions 112b of the one side portion 20 and the other side portion 22 are disposed at positions adjacent to each other. However, the present invention is not limited to this. May be provided on different sides of the base 8 having a polygonal shape in plan view, and the fitting portion 8b may be formed at each position.
Further, the outer peripheral side wall 3a of the yoke 3 may have a circular shape in plan view as long as the protruding wall 8c facing the entire circumference of the yoke 3 can be formed, and the corner portion 14 may not have a chamfered shape. For example, an arc shape may be used.

DESCRIPTION OF SYMBOLS 1 Lens drive device 3 Yoke 3a Outer peripheral side wall 5 Lens support body 8 Base 8c Projection wall 11 Rear side spring 13 Magnet 19 Coil

Claims (5)

A lens support for supporting the lens on the inner periphery, a coil provided on the outer periphery of the lens support, an annular yoke on which the lens support is movably disposed on the inner periphery, and a coil attached to the yoke And a magnet that is electrically connected to the coil and that holds the lens support movably, and a base that is placed on one side of the yoke in the optical axis direction and holds the spring. A lens driving device that moves the lens support back and forth along the optical axis direction of the lens by electromagnetic force generated by energizing the coil from the spring,
A lens driving device characterized in that a protruding wall facing the inner peripheral surface of the outer peripheral side wall of the yoke is formed on the base. The base has a quadrangular shape when viewed from the front side in the optical axis direction,
The spring is an annular leaf spring, and an inner peripheral side portion attached to the lens support, an outer peripheral side portion attached to the base, and an arm portion that can be elastically deformed by connecting each inner peripheral side portion and the outer peripheral side portion. And
2. The lens driving device according to claim 1, wherein the outer peripheral side portion has a long side portion that extends from one corner portion of the base adjacent to each other to the other corner portion and is disposed inside the protruding wall. .   The lens driving device according to claim 1, wherein the base has a fitting portion that fits with an end of the spring.   An autofocus camera comprising the lens driving device according to claim 1.   A camera-equipped mobile terminal equipped with the autofocus camera according to claim 4.

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