JP5323920B2 - Lens drive device - Google Patents

Description

  The present invention relates to a lens driving device used by being incorporated in a camera, a portable information terminal device, or the like.

  Conventionally, as a technology in such a field, there is JP 2010-72545 A. In the lens driving device described in this publication, the first to fourth lens groups are arranged in a box-shaped lens barrel body, and the fourth lens group is fixed to a lens moving frame guided by a guide bar. Has been. The lens moving frame and the moving frame are connected by a tension coil spring, the hook on one end side of the tension coil spring is hooked on the spring hook portion of the lens moving frame, and the hook on the other end side of the tension coil spring is movable by a lead screw. It is hooked on the spring hook of the moving frame. Each spring hook portion is formed with a groove portion for hooking the hook, and an inclined surface for facilitating the hook hooking operation is formed adjacent to the groove portion.

JP 2010-72545 A

  The conventional spring hooking portion is formed with a spring drop prevention piece standing upright adjacent to the groove portion. Then, when performing the operation of hooking the hook on the spring hook, it is necessary to insert a spring-removal prevention piece into the hook, and in order to do this, an operation of tilting the hook inward is required. However, the smaller the lens driving device and the smaller the spring diameter of the tension coil spring, the smaller the hook becomes. Therefore, in conventional operations, the hook is easily deformed, and the hook There is a problem that it becomes difficult to hook the groove in the groove.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lens driving device that improves workability and makes it difficult for deformation of a hook to occur when an operation of hooking a hook of a tension coil spring into a groove portion of a spring hook portion.

The present invention relates to a lens driving device in which a lens frame to which a lens is fixed is moved along a guide shaft, and a hook of a tension coil spring for urging the lens frame in one direction is hooked on the lens frame. ,
The spring hook provided on the lens frame is
A hook body formed protruding from the lens frame;
A groove portion formed on the surface of the hook body and extending in a direction substantially perpendicular to the protruding direction of the hook body;
A guide portion provided to protrude outward from the groove portion in the hook body,
When the extending direction of the groove is the X direction, the protruding direction of the hook body is the Y direction, the direction perpendicular to the X direction and the Y direction is the Z direction, one end of the groove is the front side, and the other end of the groove is the back side In addition,
The guide slope formed adjacent to the groove portion in the guide portion has a top portion that is positioned at the top in the Z direction on the near side in the X direction, and is lowered from the top portion toward the back side.

  In this lens driving device, the hook is naturally moved 90 degrees from the front side of the guide part beyond the top of the guide slope and hooked to the guide part. Are guided to the groove part and dropped into the groove part. Therefore, in order to hook the hook of the tension coil spring into the groove of the spring hook, it is only necessary to hook the hook over the guide slope and beyond the top of the guide slope. Since there is no need to deform as described above, deformation of the hook can be prevented.

Further, the guide slope is a right triangle as viewed from the Z direction.
When such a configuration is employed, the hook can be moved along the hypotenuse of the guide slope when the hook is hooked, so that the hook can be smoothly moved by line contact.

The guide portion is formed with a cut-off surface that is cut outward from the oblique side of the guide slope extending from the top.
By adopting such a configuration, when the hook is guided to the groove along the guide slope while moving 90 degrees, it is possible to avoid a situation in which the hook is caught in the middle of the guide part and cannot be moved 90 degrees. it can.

Further, the guide part is provided with an extension part protruding in the X direction.
When such a configuration is adopted, the hook is difficult to come off because it hits the extended portion in the event of dropping or vibration. In addition, since the extension portion protrudes in the X direction, it does not interfere with the operation of hooking the hook from the near side of the guide portion over the top of the guide slope to the guide portion.

  According to the present invention, when the operation of hooking the hook of the tension coil spring on the groove portion of the spring hook portion is performed, the workability is improved and the hook is hardly deformed.

It is a perspective view which shows one Embodiment of the lens drive device which concerns on this invention. It is sectional drawing of FIG. It is a perspective view which shows the state which connected the 1st lens frame and the 2nd lens frame with the tension | pulling coil spring. It is the perspective view which looked at the spring hook part from various angles. (A) is a top view of a spring hook part, (b) is a side view of a spring hook part, (c) is a front view of a spring hook part. It is a perspective view which shows the state which the hook is moving along the guide slope of a spring hook part.

  Hereinafter, a preferred embodiment of a lens driving device according to the present invention will be described in detail with reference to the drawings.

  As shown in FIGS. 1 to 3, the lens driving device 1 is incorporated in, for example, a thin digital camera or a portable information terminal device with an imaging function, and drives the zoom lens M and the focus lens N. The camera shake correction unit P is also provided. The zoom lens M and the focus lens N are composed of lens groups.

  In the lens driving device 1, the zoom lens M and the focus lens N are disposed so that their optical axes L coincide. The lens driving device 1 can drive the zoom lens M and the focus lens N in a direction along the optical axis L (hereinafter referred to as an optical axis L direction). In a device such as a digital camera, an image sensor such as a CCD or a CMOS is provided outside the lens driving device 1.

  The lens driving device 1 includes a base member 2, a light bending portion 3 for bending an optical path, a first lens frame 4 on which a zoom lens M is mounted, and a second lens frame 5 on which a focus lens N is mounted. A shutter frame 6 disposed between the first lens frame 4 and the second lens frame 5 and mounted with a shutter 6a, and the first and second lens frames 4 extending in the optical axis L direction. , 5 and guide shafts 7 and 8 that pass through the shutter frame 6 and a first stepping motor 10 in which a lead screw 10a is screwed to the first lens frame 4 in order to move the first lens frame 4. And a second stepping motor 11 in which a lead screw 11a is screwed to the second lens frame 5 in order to move the second lens frame 5.

  The base member 2 accommodates the zoom lens M and the focus lens N and is formed in a flat box shape. Both ends of guide shafts 7 and 8 extending in the optical axis L direction are fixed in the base member 2, and the lens frames 4 and 5 are smoothly moved in the optical axis L direction along the guide shafts 7 and 8. Moved.

  The light bending portion 3 is provided outside the base member 2 and is used for bending the subject light from the subject and taking it into the base member 2. The light bending portion 3 has a substantially triangular prism shape inside. The prism 3a is fixed. The light from the subject is bent at right angles to the optical axis L direction by the prism 3a, and the camera shake correction lens disposed in the zoom lens M, the shutter 6a, the focus lens N, and the camera shake correction unit P in the base member 2. And is emitted to the outside of the base member 2 and imaged by an image sensor such as a CCD or CMOS.

  When the first lens frame 4 is driven along the guide shafts 7 and 8, the lead screw 10 a of the first stepping motor 10 is in contact with the first lens frame 4 and the first nut portion 10 b. It is screwed on. Similarly, when the second lens frame 5 is driven along the guide shafts 7 and 8, the lead screw 11 a of the second stepping motor 11 is in contact with the second lens frame 5. The nut portion 11b is screwed.

  As shown in FIGS. 2 and 3, a first nut mounting portion 4 a for mounting the first nut portion 10 b is formed in a concave shape at the end of the first lens frame 4. A second nut mounting portion 5a for mounting the second nut portion 11b is also formed in a concave shape at the end of the lens frame 5. The first lens frame 4 and the second lens frame 5 through which the guide shafts 7 and 8 pass are arranged in parallel, and a zoom lens M and a focus lens N are arranged on the optical axis L. The first nut portion 10 b and the second nut portion 11 b are disposed so as to face each other between the first lens frame 4 and the second lens frame 5.

  As shown in FIG. 3, the first lens frame 4 is provided with a first spring hook 12 positioned in the vicinity of the first nut mounting portion 4 a at the end of the first lens frame 4. 5 is provided with a second spring hook 13 located in the vicinity of the second nut mounting portion 5a. The hooks 20a and 20b of the tension coil spring 20 are hooked on the first and second spring hooks 12 and 13, respectively. By using the tension coil spring 20, the first nut mounting portion 4a can be securely pressed to the first nut portion 10b screwed to the lead screw 10a, and the second screw screwed to the lead screw 11a. The second nut mounting portion 5a can be securely crimped to the nut portion 11b.

  The second spring hook 13 is a hook body 13a that protrudes in a direction orthogonal to the end of the second lens frame 5 with respect to the optical axis L, and is perpendicular to the optical axis L direction at the end of the hook main body 13a. It is formed by a bent omission prevention piece 13b and a groove portion 13c formed in the hook body 13a in the vicinity of the omission prevention piece 13b and extending in a direction substantially orthogonal to the protruding direction of the hook body 13a. Yes.

  Next, the first spring hook 12 will be described in detail.

  As shown in FIGS. 3 to 5, the first spring hook 12 is formed on the surface of the hook body 21 that protrudes from the first lens frame 4, and the hook body 21. The linear groove part 22 extended in the direction substantially orthogonal to the protrusion direction of 21 and the guide part 23 provided in the hook main body 21 so as to protrude outward from the groove part 22. Further, the bottom portion of the groove portion 22 is formed in a V-shaped cross section in order to improve the seating stability of the hook 20a.

  In the following description, the extending direction of the groove portion 22 is the X direction, the protruding direction of the hook body 21 is the Y direction, the direction orthogonal to the X direction and the Y direction is the Z direction, and one end side of the groove portion 22 (the tension coil spring is hooked). Side) is the front side, and the other end side of the groove 22 (the opposite side in the X direction with respect to the one end side) is the back side.

  A guide slope 23 a adjacent to the groove 22 is formed in the guide 23 of the first spring hook 12. The guide slope 23a has a top portion 23b positioned at the top in the Z direction on the near side in the X direction, and is lowered from the top portion 23b toward the back side. And this guide slope 23a has comprised the right triangle shape seeing from the Z direction (refer Fig.5 (a)).

  By adopting such a guide slope 23a, as shown in FIG. 6, the hook 20a of the tension coil spring 20 is hooked on the guide part 23 from the front side of the guide part 23 over the top part 23b of the guide slope 23a. The hook 20a is guided to the groove portion 22 along the guide inclined surface 23a while being naturally moved 90 degrees by the tensile force of the tension coil spring 20 only by performing a simple operation, and dropped into the groove portion 22. Accordingly, when the hook 20a of the tension coil spring 20 is hooked on the groove portion 22 of the spring hooking portion 12, the hook 20a only needs to be hooked over the guide portion 23 beyond the top portion 23b of the guide slope 23a. The hook 20a does not need to be deformed more than necessary, and the deformation of the hook 20a can be prevented. In this case, the hook 20b of the tension coil spring 20 is hooked on the second spring of the second lens frame 5 before the hook 20a of the tension coil spring 20 is hooked on the first spring hook 12 of the first lens frame 4. It is necessary to hook the part 13 in advance (see FIG. 3).

  In addition, by making the guide slope 23a into a right triangle when viewed from the Z direction, the hook 20a can be moved along the hypotenuse A of the guide slope 23a when performing the operation of hooking the hook 20a. Thus, the hook 20a can be moved smoothly.

  As shown in FIGS. 3 to 5, the guide portion 23 is formed with a cut-out surface 23 c that is cut outward from the oblique side A of the guide slope 23 a extending from the top portion 23 b. The cut-off surface 23c has a right-angled triangular shape as viewed from the Z direction, and the cut-off surface 23c and the guide slope 23a are rectangular as viewed from the Z direction. (See FIG. 5 (a)).

  By adopting such a cut-off surface 23c, when the hook 20a is guided to the groove portion 22 along the guide inclined surface 23a while moving 90 degrees, the hook 20a can be caught by the guide section 23 and moved 90 degrees. It is possible to avoid such a situation that it disappears. That is, the cut-off surface 23c is employed as a measure for reducing the guide portion 23 in order to guide the hook 20a smoothly to the groove portion 22.

  Further, the guide portion 23 is provided with an extension portion 23d that protrudes in the X direction toward the front side. When such a configuration is employed, the hook 20a hits the extended portion 23d and is difficult to come off when dropped or vibrated. In addition, since the extended portion 23d protrudes in the X direction, it may be an obstacle when the hook 20a is hooked on the guide portion 23 from the front side of the guide portion 23 beyond the top portion 23b of the guide slope 23a. Absent. The extended portion 23d forms part of the guide portion 23, and the guide slope 23a and the cut-off surface 23c extend to the extended portion 23d in the guide portion 23.

  It goes without saying that the present invention is not limited to the embodiment described above. For example, the guide slope 23a may be a flat surface or a curved surface. Similarly, the cut-off surface 23c may be a flat surface or a curved surface.

  DESCRIPTION OF SYMBOLS 1 ... Lens drive device, 4 ... Lens frame, 7, 8 ... Guide shaft, 12 ... Spring hook part, 20 ... Tension coil spring, 20a ... Hook, 21 ... Hook body, 22 ... Groove part, 23 ... Guide part, 23a ... Guide Slope, 23b ... top, 23c ... cut-off surface, 23d ... expanded part, A ... slope, M ... lens, L ... optical axis.

Claims (4)

In a lens driving device in which a lens frame to which a lens is fixed is moved along a guide shaft, and a hook of a tension coil spring for urging the lens frame in one direction is hooked on the lens frame.
The spring hook provided on the lens frame is
A hook body formed protruding from the lens frame;
A groove formed on the surface of the hook body and extending in a direction substantially perpendicular to the protruding direction of the hook body;
A guide portion provided outwardly projecting from the groove portion in the hook body,
The extending direction of the groove portion is the X direction, the protruding direction of the hook body is the Y direction, the direction orthogonal to the X direction and the Y direction is the Z direction, one end side of the groove portion is the front side, and the other end side of the groove portion is the rear side. Side
The guide slope formed adjacent to the groove portion in the guide portion has a top portion located at the top in the Z direction on the near side in the X direction, and is lowered from the top portion toward the back side. Lens drive device.   The lens driving device according to claim 1, wherein the guide slope has a right triangle shape when viewed from the Z direction.   The lens driving device according to claim 2, wherein the guide portion is formed with a cut-off surface that is cut outward from a hypotenuse of the guide slope extending from the top portion.   The lens driving device according to claim 1, wherein the guide portion is provided with an extension portion protruding in the X direction.

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