JP2016051075A - Lens drive device and optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device which achieves simplification, reduction in size and weight and the like of the structure thereof and furthermore can surely transmit driving force to a lens by preventing a backlash between a lead screw and female screw part, and to provide an optical device using the lens drive device.SOLUTION: There is provided the lens drive device including : a base 10; a lens frame 30 having a female screw part 34 and supported freely movably in an optical axis direction; and a motor 40 to which a lead screw 41 engaging with the female screw part is directly connected. The lens drive device further includes a supporting mechanism (a motor holder 50, guide shaft 21, and positioning pin 15a) that supports the motor 40 movably in a direction forming a prescribed angle relative to an optical axis L2 direction, and an urging member 60 that urges the motor 40 in the movable direction. Accordingly, simplification, reduction in size and weight of the structure of the lens drive device and the like can be achieved, a backlash between the lead screw and the female screw part can be prevented, and driving force can be surely transmitted.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a lens driving device and an optical device applied to an optical device such as a camera and an optical pickup, and in particular, a screw feed structure by meshing (screwing) a lead screw having a male screw and a nut or rack having a female screw. The present invention relates to a lens driving device that drives a lens frame or the like holding a lens in the optical axis direction, and an optical device using the same.

As a conventional lens driving device, a case, a motor holder fixed to the case, a motor fixed to the motor holder, a lead screw directly connected to the motor (having a male screw), and a lead screw are arranged in parallel with the lead screw. Guide shaft (main guide shaft, sub guide shaft) fixed to the base, lens frame supported so as to be able to reciprocate with respect to the guide shaft, and lens frame (integrally formed or connected) to move integrally In addition, a half nut or the like (having a female thread) that engages (screws) with the lead screw is provided, and the motor is activated to rotate the lead screw (depending on the engagement (screwing) relationship between the lead screw and the half nut) A lens frame that is driven in the optical axis direction is known (see, for example, Patent Document 1 and Patent Document 2).
However, in this lens driving device, the lead screw and the half nut are merely arranged so as to mesh (screw), causing backlash between the male screw and the female screw, and driving the lens frame with high accuracy. Difficult to do.

Other lens driving devices include a motor, a lead screw directly connected to the motor (with a male screw), a guide shaft (two guide shafts) arranged in parallel to the lead screw, and a reciprocating motion with respect to the guide shaft. A freely supported lens frame, a rack that is swingably connected to the lens frame (around an axis parallel to the guide shaft) and meshes with the lead screw (having a female screw), and the rack is biased in the optical axis direction In addition, a coil spring or the like that rotates and energizes the lead screw in the direction of meshing with the lead screw, and by starting the motor and rotating the lead screw (by the meshing (screwing) relationship of the lead screw and the rack), the lens frame is moved to the optical axis. A device that is driven in a direction is known (for example, see Patent Document 3).
However, in this lens driving device, since the lens frame is provided with a connecting sleeve and the like and a biasing coil spring for detachably connecting the rack to the lens frame, the lens frame is enlarged. In addition, the movable weight is increased, and the driving load is increased by the increase in weight.

JP 2007-271649 A JP 2005-121882 A JP-A-5-27149

  The present invention has been made in view of the above circumstances, and the object of the present invention is to provide a lead screw (male thread) and a female thread ( A lens driving device that can prevent rattling of the female screw) and reliably transmit the driving force, and can provide a stable driving force irrespective of the driving stroke of the lens frame, and a lens driving device using the same. It is to provide an optical device.

A lens driving device according to the present invention includes a base, a lens frame having a female screw portion and supported so as to be movable in the optical axis direction, and a motor directly connected to a lead screw meshing with the female screw portion. The apparatus includes a support mechanism that movably supports the motor in a direction that forms a predetermined angle with respect to the optical axis direction, and an urging member that urges the motor in the movable direction.
According to this configuration, when the lead screw rotates by starting the motor, a driving force is applied to the lens frame due to the meshing (screwing) relationship between the lead screw and the female screw portion, and the lens frame moves in the optical axis direction.
Here, the motor directly connected to the lead screw is movably supported by a support mechanism in a direction that forms a predetermined angle with respect to the optical axis direction (for example, a direction perpendicular to the optical axis direction, a direction including an oblique direction in the vicinity of the vertical axis, etc.). Since the biasing member is biased in the movable direction, the lead screw and the female screw portion are loosely moved in the movable direction, and the male screw of the lead screw and the female screw of the female screw portion are Due to the wedge action, rattling is performed also in the axial direction (optical axis direction) of the lead screw. This prevents rattling of the lead screw (male thread) and the female thread part (female thread), can transmit the driving force reliably, and is stable regardless of the lens frame driving stroke. A driving force can be exerted, and the lens frame can be driven to a desired position with high accuracy.

In the above configuration, the support mechanism is provided on the base for positioning the motor holder in the optical axis direction, the motor holder that fixes the motor, the support portion that supports the motor holder in a plane perpendicular to the optical axis direction, and the motor holder. It is possible to adopt a configuration including a positioning portion formed.
According to this configuration, the motor (and the lead screw) is movably supported by the support portion (provided on the base) while the position in the optical axis direction is positioned by the positioning portion of the base via the motor holder. By adopting such a support mechanism, the motor (and the lead screw) are movably supported so as to obtain a reliable meshing (screwing) relationship while achieving simplification, size reduction, weight reduction, and the like of the structure. Can do.

In the above configuration, the support portion may employ a configuration in which the motor holder is supported so as to be rotatable about an axis parallel to the optical axis direction.
According to this configuration, since the motor (and the lead screw) is rotatably supported in a plane perpendicular to the optical axis direction, the lead screw is rotated in either one direction or the other direction. In addition, since the male screw and the female screw are engaged (screwed) under the same conditions, the lens frame can be stably driven with high accuracy regardless of the feeding (moving) direction of the lens frame.

In the above configuration, the urging member may be a torsion coil spring having one end hooked to the motor and the other end hooked to the base.
According to this configuration, by adopting a torsion coil spring as the urging member, it is possible to easily exert an urging force on the motor (and the lead screw) while achieving integration of parts, downsizing of the apparatus, and the like. it can.

In the above configuration, it is possible to adopt a configuration that includes a guide shaft that guides the lens frame in the optical axis direction, and the guide shaft also serves as the support portion.
According to this configuration, since the guide shaft also serves as a support portion that movably supports the motor (and the lead screw), the lead screw directly connected to the motor and the female screw portion of the lens frame with high accuracy can be used with the guide shaft as a reference. Therefore, the meshing (screwing) relationship between the male screw and the female screw can be set with higher accuracy.

In the above configuration, the biasing member may be a torsion coil spring having one end hooked to the motor and the other end hooked to the base and the coil portion disposed around the guide shaft. .
According to this configuration, by adopting a torsion coil spring arranged around the guide shaft as the urging member, while achieving integration of parts, downsizing of the device, etc., the motor (and the lead screw), Only the rotational biasing force around the guide shaft can be exerted.

In the above configuration, the female screw portion is a half nut formed in a substantially U shape, and the half nut can employ a configuration in which a female screw is formed only on one inner surface.
According to this configuration, since the female screw portion is a substantially U-shaped half nut, it is possible to obtain a meshing (screwing) relationship between the two by simply dropping the lead screw into the female screw portion. It can be easily attached, and since the female screw is provided only on one inner surface of the half nut, the lens frame and the female screw part are molded integrally using a resin material or the like. Can be improved.

In the above configuration, the motor holder includes a long hole extending in a direction perpendicular to the optical axis direction, and the positioning portion is a positioning pin formed to protrude from the base so as to be fitted into the long hole. can do.
According to this configuration, since the positioning in the optical axis direction can be performed only by fitting the positioning pin of the base into the long hole of the motor holder, the assembling work can be facilitated.

An optical device according to the present invention includes a lens driving device having any one of the above-described configurations.
According to this configuration, the optical device including the lens driving device having the above-described configuration is used to achieve the simplification, size reduction, weight reduction, and the like of the optical device such as a camera and an optical pickup, and the like. Prevents rattling of the screw (male thread) and female thread part (female thread), can transmit the driving force reliably, and exerts a stable driving force regardless of the driving stroke of the lens frame Therefore, a focusing operation and a zooming operation can be performed with high accuracy in a camera or the like, and information can be recorded and reproduced with high accuracy with an optical pickup or the like.

  According to the lens driving device having the above-described structure, the lead screw (male screw) and the female screw part (female screw) can be loosely engaged with each other while the structure is simplified, reduced in size, reduced in weight, and the like. Therefore, it is possible to obtain a lens driving device that can reliably transmit the driving force and can exert a stable driving force regardless of the driving stroke of the lens frame.

It is a perspective view which shows one Embodiment of the lens drive device which concerns on this invention. FIG. 2 is a partially exploded perspective view of the lens driving device shown in FIG. 1 with some components omitted. FIG. 3 is a partially enlarged perspective view in which a part of the lens driving device shown in FIG. 2 is enlarged. FIG. 2 shows a lens frame included in the lens driving device shown in FIG. 1, (a) is a front view seen from the front in the optical axis direction, and (b) is a view of the lens frame shown in (a) from below. It is a side view. FIG. 5 shows a female screw portion (half nut) provided on the lens frame shown in FIG. 4, (a) is a side view of a substantially U-shaped half nut viewed from the opening side, and (b) is (a). It is sectional drawing in EE in the inside. It is a perspective view which shows the motor and motor holder which directly connected the lead screw contained in the lens drive device shown in FIG. 1 is a partial perspective view showing a lens frame, a guide shaft, a motor directly connected to a lead screw, a motor holder to which the motor is fixed, a torsion coil spring as a biasing member, and a positioning pin as a base positioning portion in the lens driving device shown in FIG. It is.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIGS. 1 to 7, the lens driving device M includes a housing 10 as a base that defines an outer contour, guide shafts 21 and 22, a movable lens group G1 (lens frame 30), and other lens groups ( A prism G2 that bends the optical axis L1 to the optical axis L2, fixed lens groups G3 and G4, an image blur correction lens group G5, and the like), a motor 40 and a lead screw as a drive source that drives the movable lens group G1 in the direction of the optical axis L2. 41, a motor holder 50 for fixing the motor 40, a torsion coil spring 60 as an urging member for urging the motor 40 in a direction forming a predetermined angle with respect to the optical axis L2 direction, and the like.

That is, as shown in FIGS. 1 and 2, the optical system in this lens driving apparatus bends subject light that has entered from the optical axis L1 direction by the prism G2 in the optical axis L2 direction, so that the fixed lens group G3 → movable lens. Through the group G1 → the fixed lens group G4 → the image blur correction lens group G5, the light is guided to an image pickup device or the like disposed behind, and the movable lens group G1 is appropriately driven to perform a focusing operation, and image blur correction is performed. The lens group G5 is appropriately driven to perform image blur correction.
The other lens groups (prism G2, fixed lens groups G3 and G4, image blur correction lens group G5, etc.) are examples, and may include lens groups having other configurations.

  As shown in FIGS. 1 to 3 and 7, the housing 10 is formed of a resin material in a box shape having a substantially rectangular cross section and extending in the direction of the optical axis L <b> 2. The front wall 11 located at the front, the rear wall 12 located at the rear in the optical axis L2 direction, the side walls 13 and 14 facing the direction perpendicular to the optical axis L2 direction, the bottom wall 15 and the front wall 11 are detachably formed. The auxiliary member 16 that accommodates the prism G2, the hooking wall 17 that is formed by bending from the front wall 11 and the end of the torsion coil spring 60 is hooked, the opening 18 that faces the bottom wall 15, and the opening 18 are provided. A cover member 19 (shown by a two-dot chain line) formed so as to be detachable so as to be covered is provided.

As shown in FIG. 2, the front wall 11 has two fitting holes 11a for fixing the guide shafts 21 and 22 in parallel with the optical axis L2, and three screw holes 11b for fastening the auxiliary member 16 with screws B. , A fitting hole 11c for fitting and fixing the fixed lens group G3, a receiving portion 11d for receiving one end surface of the coil portion 61 of the torsion coil spring 60, and the like.
As shown in FIG. 2, the rear wall 12 has two fitting holes 12a for fixing the guide shafts 21 and 22 in parallel with the optical axis L2, and a substantially rectangular opening 12b that opens on the optical axis L2. A mounting portion 12c or the like for mounting a substrate or the like on which an image sensor is mounted is provided.
As shown in FIG. 7, the bottom wall 15 is provided with positioning pins 15 a and the like that are formed to protrude as positioning portions for positioning the motor holder 50 in the optical axis L <b> 2 direction (fitted to the long holes 54 of the motor holder 50). I have.
The auxiliary member 16 includes two fitting holes 16a for fitting the tip portions of the guide shafts 21 and 22, three through holes 16b through which the screws B are passed, a receiving portion 16c that receives the other end surface of the coil portion 61 of the torsion coil spring 60, and the like. It has.

The guide shafts 21 and 22 each have a circular cross section and are formed so as to extend in the direction of the optical axis L2. The front end portions of the guide shafts 21 and 22 are respectively fitted in the corresponding fitting holes 11a, and the rear end portions thereof are fitted. The fitting holes 12a are respectively fitted and fixed to the housing 10 in a state parallel to the optical axis L2 direction.
The guide shaft 21 defines an axis S parallel to the optical axis L2, guides the lens frame 30 of the movable lens group G1 in the optical axis L2 direction, and moves the movable lens group G1, the prism G2, and the fixed lens group G4. The optical axis alignment of the image blur correction lens group G5 and the image sensor (not shown) attached to the attachment portion 12c of the rear wall 12 is performed.
As shown in FIG. 7, the guide shaft 21 supports the motor holder 50 so as to be movable in a plane perpendicular to the optical axis L2 direction (here, around an axis S parallel to the optical axis L2 direction). It has come to serve as a part.
Further, the guide shaft 22 guides the lens frame 30 of the movable lens group G1 in the direction of the optical axis L2 while restricting the rotation of the lens frame 30 around the guide shaft 21, and also includes the movable lens group G1, the prism G2, the fixed lens group G4, Optical axis alignment of the image blur correction lens group G5 and an image sensor (not shown) attached to the attachment portion 12c of the rear wall 12 is performed.

The movable lens group G1 is driven to perform a focusing operation, and holds the lens G as shown in FIGS. 1, 2, 4, 5A, 5B, and 7. A lens frame 30 is provided.
As shown in FIGS. 4, 5A, 5B, and 7, the lens frame 30 extends in one direction from the annular holding portion 31 that holds the lens G in a fitted state, and the annular holding portion 31. A cylindrical connecting cylindrical portion 32 that is formed and slidably connected to the guide shaft 21, and a connecting elongated hole portion 33 that extends from the annular holding portion 31 in the other direction and is slidably connected to the guide shaft 22. A half nut 34 as a female screw portion formed by extending from the connecting cylindrical portion 32, a detection piece 35 that extends from the annular holding portion 31 and can be detected by a detection sensor (not shown), and the like.

The connecting cylindrical portion 32 is formed to have a predetermined length in the direction of the optical axis L2 and is formed so that the guide shaft 21 is slidably closely fitted.
The connecting long hole portion 33 closely slidably fits the guide shaft 22 in the rotational direction around the guide shaft 21, and guides with a predetermined gap in the direction in which the guide shaft 21 and the guide shaft 22 are arranged. It is configured to receive the shaft 22.

As shown in FIG. 4 and FIGS. 5A and 5B, the half nut 34 is formed in a substantially U shape that opens toward the bottom surface 15 in the assembled state, and the female screw is formed only on one inner surface thereof. 34a is formed.
The half nut 34 has a female screw 34a meshing with the male screw 41a of the lead screw 41, so that the driving force by the feed screw structure is transmitted.
Here, since the substantially U-shaped half nut 34 is employed as the female screw portion, the engagement (screwing) relationship between the two can be obtained simply by dropping the lead screw 41, and therefore the assembly work is easy. In addition, since the female screw 34a is provided only on one inner surface of the half nut 34, when the lens frame and the female screw portion are integrally molded using a resin material or the like, its moldability is improved. Can be improved.

The motor 40 generates a rotational driving force such as a DC motor, for example, and includes a cylindrical case 40a as shown in FIGS. 3, 6, and 7, in which a rotor (not shown) is provided. A stator (not shown) and the like are accommodated, and a lead screw 41 is directly connected and rotatably supported so as to rotate integrally with the rotor. Further, the rotor and the lead screw 41 are urged in the axial direction by an urging spring or the like housed inside to prevent backlash in the axial direction.
As shown in FIG. 6, the lead screw 41 has a helical male screw 41 a that meshes with the half nut 34 (the female screw 34 a thereof) of the lens frame 30.

As shown in FIGS. 6 and 7, the motor holder 50 is formed by bending a metal plate or the like, and a fixed wall portion 51 for fixing the case 40 a of the motor 40 and a tip end portion of the lead screw 41 are freely rotatable. The two fitting holes 53 and the positioning pin 15a of the housing 10 are fitted on the axis S parallel to the optical axis L2 direction so that the guide shaft 21 serving as the support portion and the guide shaft 21 as the support portion are fitted. Accordingly, a long hole 54 and the like extending in the direction PL perpendicular to the optical axis L2 direction are provided.
In the motor holder 50, the guide shaft 21 is fitted into the two fitting holes 53 and the long hole 54 is fixed in a state where the motor 40 is fixed and the tip end portion of the lead screw 41 is rotatably supported. By fitting the positioning pin 15a, the motor 40 and the lead screw 41 can be rotated around an axis S parallel to the optical axis L2 direction (optical axis L2) while positioning the motor 40 and the lead screw 41 at predetermined positions in the optical axis L2 direction. (Movable in a plane perpendicular to the direction).

In the above configuration, the motor holder 50 that fixes the motor 40, the guide shaft 21 as a support portion that supports the motor holder 50 movably in a plane perpendicular to the optical axis L2 direction, and the motor holder 50 in the optical axis L2 direction. A positioning mechanism 15 that is provided on the housing 10 for positioning constitutes a support mechanism that movably supports the motor 40 in a direction that forms a predetermined angle with respect to the direction of the optical axis L2 (here, a vertical direction).
By adopting such a support mechanism, the motor 40 (and the lead screw 41) is movably supported so as to obtain a reliable meshing (screwing) relationship while achieving simplification, size reduction, weight reduction, and the like. can do.
Further, since the guide shaft 21 also serves as a support portion that movably supports the motor 40 (and the lead screw 41), the guide shaft 21 is directly connected to the female screw portion (half nut 34) of the lens frame 30 and the motor 40 with the guide shaft 21 as a reference. The lead screw 41 can be positioned with high accuracy, and therefore the meshing (screwing) relationship between the male screw 41a and the female screw 34a can be set with higher accuracy. Furthermore, since the positioning in the direction of the optical axis L2 can be performed only by fitting the positioning pin 15a of the housing 10 into the long hole 54 of the motor holder 50, the assembling work can be facilitated.

As shown in FIGS. 2, 3, and 7, the torsion coil spring 60 includes a coil portion 61, one end portion 62 that extends from the coil portion 61, and the other end portion 63.
The torsion coil spring 60 has one end 62 hooked on the case 40a of the motor 40 in a state where the coil portion 61 is disposed around the guide shaft 21 (a state where the guide shaft 21 is inserted through the coil portion 61). The other end 63 is hooked on the hooking wall 17 of the housing 10 and exerts a biasing force to rotate and bias the motor 40 (and the lead screw 41) in the direction of the arrow R around the axis S.
Here, by adopting a torsion coil spring 60 disposed around the guide shaft 21 as an urging member, the motor 40 (and the lead screw 41) can be reduced while achieving the integration of parts and the miniaturization of the apparatus. Only the rotation urging force around the guide shaft 21 can be exerted.

  According to the lens driving device having the above-described configuration, the motor 40 directly connected to the lead screw 41 makes a predetermined angle with respect to the optical axis L2 direction by the support mechanism (the motor holder 50, the guide shaft 21, and the positioning pin 15a) ( Here, since it is movably supported in the direction perpendicular to the optical axis L2 direction and urged in the movable direction (direction PL perpendicular to the optical axis L2 direction) by the urging member (torsion coil spring 60), In the movable direction, the lead screw 41 and the female screw portion (half nut 34) are loosely moved, and the wedge action between the male screw 41a of the lead screw 41 and the female screw 34a of the female screw portion (half nut 34). The backlash is also performed in the direction of the axis S of the lead screw 41 (direction of the optical axis L2).

As a result, rattling of the lead screw 41 (the male screw 41a) and the female screw portion (the female screw 34a of the half nut 34) can be prevented and the driving force can be reliably transmitted, and the lens frame A stable driving force can be exerted regardless of the driving stroke of 30, and the lens frame 30 can be driven to a desired position with high accuracy.
Further, the motor holder 50 is supported by the guide shaft 21 as a support portion so as to be rotatable about an axis S parallel to the optical axis L2 direction. That is, the motor 40 (and the lead screw 41) is supported in the optical axis L2 direction. Since the lead screw 41 is rotated in either one direction or the other direction, the male screw 41a and the female screw 34a are under the same condition. Since the meshing (screwing) is performed, the lens frame 30 can be stably driven with high accuracy regardless of the feeding (moving) direction of the lens frame 30.

Next, assembly of the lens driving device will be described.
Prior to the assembly, the housing 10 (and the auxiliary member 16 and the cover 19 with the prism G2 assembled) with the fixed lens group G3 and the like, the two guide shafts 21 and 22, the movable lens group G1, and the fixed lens. A group G4, an image blur correction lens group G5, a motor module (a module in which the motor 40 is fixed to the motor holder 50 and the lead screw 41 is rotatably supported), a torsion coil spring 60, and the like are prepared.

  First, a motor module (a motor holder 50 to which a motor 40 that directly connects the lead screw 41) is fixed, a movable lens group G1, a fixed lens group G4, an image blur correction lens group G5, and the like are arranged at predetermined positions in the housing 10. The At this time, the positioning pin 15 a of the housing 10 is fitted into the long hole 54 of the motor holder 50, and the lead screw 41 is fitted so as to mesh with the half nut 34.

  Subsequently, the guide shaft 21 is connected to the fitting hole 11a of the housing 10 → the connecting cylindrical portion 32 of the lens frame 30 → the other fitting hole 53 of the motor holder 50 → the positioning hole of the fixed lens group G4 → the image blur correction lens group. G5 positioning hole → fitted into the fitting hole 12a of the housing 10 and fixed, and the guide shaft 22 is fitted into the fitting hole 11a of the housing 10 → the connecting long hole portion 33 of the lens frame 30 → fixed lens group. G4 positioning hole → image blur correction lens group G5 positioning hole → fitting hole 12a of housing 10 is fitted and fixed.

Subsequently, the coil portion 61 of the torsion coil spring 60 is fitted into the portion protruding from the front wall 11 of the guide shaft 21, the one end portion 62 is hooked on the case 40 a of the motor 40, and the other end portion 63 is the housing 10. It is latched on the retaining wall 17.
As a result, a biasing force is applied to rotate and bias the motor 40 (and the lead screw 41) in the direction of the arrow R around the axis S, and the lead screw 41 and the half nut in the movable direction (direction PL perpendicular to the optical axis L2). 34, and also in the axis S direction (optical axis L2 direction) of the lead screw 41 due to the wedge action of the male screw 41a of the lead screw 41 and the female screw 34a of the half nut 34. .

Subsequently, the auxiliary member 16 is joined to the front wall 11 while being fitted to the guide shafts 21 and 22 so that the coil portion 61 of the torsion coil spring 60 is sandwiched between the receiving portions 11d and 16c, and is fastened by the screw B. .
Finally, a cover member 19 is attached so as to cover the opening 18 of the housing 10.
When the lens driving device is applied to an imaging device such as a camera, a substrate on which an imaging element is mounted is attached to the rear wall 12 of the housing 10.

  According to the lens driving device having the above structure, the lead screw 41 (the male screw 41a) and the female screw portion (the female screw 34a of the half nut 34) are meshed while achieving simplification, miniaturization, and weight reduction of the structure. (Screw) rattling can be prevented, the driving force can be transmitted reliably, and a stable driving force can be exerted regardless of the driving stroke of the lens frame 30.

In the above-described embodiment, the motor 40 (and the lead screw 41) is biased in a predetermined direction (around the axis S parallel to the optical axis L2 direction) in a plane perpendicular to the optical axis L2 direction. Although the case has been shown, the present invention is not limited to this, and biasing may be performed in a direction that forms a predetermined angle slightly deviated from the vertical direction with respect to the direction of the optical axis L2.
In the above embodiment, the case where the torsion coil spring 60 is employed as the urging member has been described. However, the present invention is not limited thereto, and any tension spring or motor may be used as long as it exerts an urging force in the movable direction. A magnet or the like that urges the case or the like by magnetic force or the like may be provided in the housing. Moreover, although the case where the torsion coil spring 60 was arrange | positioned around the guide shaft 21 was shown, it is not limited to this, You may employ | adopt another arrangement configuration.

In the above embodiment, the case where the guide shaft 21 is also used as the support portion that supports the motor holder 50 in a plane perpendicular to the optical axis L2 direction is shown. However, the present invention is not limited to this. Another support shaft may be provided in the housing.
In the above-described embodiment, the configuration including the motor holder 50, the support portion (guide shaft 21), the positioning pin 15a, and the like is shown as the support mechanism. However, the configuration is not limited to this, and other configurations are adopted. May be.
In the above-described embodiment, the half nut 34 integrally formed with the lens frame 30 is shown as the female screw portion that meshes (screws) with the lead screw 41. However, the present invention is not limited to this. A nut may be used, and a configuration in which a nut or a rack formed separately from the lens frame is then fixed to the lens frame may be employed.

  As described above, the lens driving device of the present invention achieves simplification, downsizing, weight reduction, and the like of the structure while meshing (screwing) the lead screw (male screw) and the female screw part (female screw). Can be transmitted reliably, and a stable driving force can be exerted regardless of the driving stroke of the lens frame, so that a portable information terminal is required to be reduced in size and cost. The present invention can be applied to a digital camera or the like mounted on a machine or the like, and is also useful as a lens driving device for other cameras or optical devices such as an optical pickup.

L1, L2 Optical axis 10 Housing 15a Positioning pin (positioning part, support mechanism)
21 Guide shaft (support, support mechanism)
22 Guide shaft S Axis 30 Lens frame 32 Connection cylindrical part 33 Connection long hole part 34 Half nut (female thread part)
34a Female screw 40 Motor 41 Lead screw 41a Male screw 50 Motor holder (support mechanism)
54 long hole 60 torsion coil spring (biasing member)
61 Coil part 62 One end part 63 Other end part

Claims (9)

A lens driving device comprising: a base; a lens frame having a female screw portion and supported movably in the optical axis direction; and a motor directly connected to a lead screw meshing with the female screw portion,
A support mechanism that movably supports the motor in a direction that forms a predetermined angle with respect to the optical axis direction;
Including a biasing member that biases the motor in its movable direction;
A lens driving device. The support mechanism includes a motor holder that fixes the motor, a support portion that supports the motor holder so as to be movable in a plane perpendicular to the optical axis direction, and the motor holder to position the motor holder in the optical axis direction. Including a positioning part provided in the base,
The lens driving device according to claim 1. The support portion supports the motor holder so as to be rotatable about an axis parallel to the optical axis direction.
The lens driving device according to claim 2. The biasing member is a torsion coil spring having one end hooked to the motor and the other end hooked to the base.
The lens driving device according to claim 3. A guide shaft for guiding the lens frame in the optical axis direction;
The guide shaft also serves as the support;
The lens driving device according to claim 3. The biasing member is a torsion coil spring having one end hooked to the motor, the other end hooked to the base, and a coil portion disposed around the guide shaft.
The lens driving device according to claim 5. The female screw portion is a half nut formed in a substantially U shape,
The half nut has a female thread formed only on one inner surface,
The lens driving device according to claim 1, wherein The motor holder includes a long hole extending in a direction perpendicular to the optical axis direction,
The positioning portion is a positioning pin formed to protrude from the base to be fitted into the elongated hole.
The lens driving device according to claim 2 or 3, wherein Including the lens driving device according to claim 1,
An optical device.

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