JP6948139B2 - Electromagnetic drive for mobile - Google Patents

Description

The present invention relates to a mobile electromagnetic drive device.

Various electromagnetic drive devices are used in mobile devices such as personal digital assistants and wearable electronic devices. In particular, various mobile devices are equipped with a camera unit, and the camera unit uses a lens driving device that drives AF (Autofocus) and OIS (Optical Image Stabilizer).

Electromagnetic drive devices such as lens drive devices are generally known as moving magnet type devices in which a drive coil is attached to the base member and a magnet is attached to a movable member that is movably supported by the base member. Has been done. In such an electromagnetic drive device, a drive coil and a wiring member or a terminal member for energizing the coil are provided on the base member. Further, in order to control the AF and OIS described above, a position sensor for detecting the position of a magnet attached to the movable member is provided on the base member (see Patent Document 1 below).

Japanese Unexamined Patent Publication No. 2016-14705

In the conventional electromagnetic drive device described above, a driving coil and a position sensor are provided on the base member, and wiring for energizing them is further provided on the base member. Therefore, the wiring structure and the terminal structure on the base member become complicated. Since the support area of the base member of the electromagnetic drive device mounted on the mobile device is small due to the high demand for space saving, it is difficult to provide a complicated wiring structure or terminal structure in a narrow space on the base member. was there.

An object of the present invention is to deal with such a situation, and in a mobile electromagnetic drive device, a drive coil and a position sensor are used as a base member without providing a complicated wiring structure or terminal structure on the base member. The challenge is to be able to deploy to.

In order to solve such a problem, the mobile electromagnetic drive device according to the present invention has the following configuration.

An electromagnetic drive device for a mobile device, the base member, a drive coil attached to the base member, a movable member to which a magnet is attached and movably supported by the base member, and the base member. provided, and a position sensor for detecting the position of the magnet, the coil is a planar substrate coils planar arrangement the windings between the multilayer insulating layers, wherein the position sensor is connected to a part of the insulating layer A mobile electromagnetic drive device comprising wiring and a terminal portion to be provided , wherein the position sensor is assembled to the base member in a state of being previously mounted on the flat substrate coil.

It is explanatory drawing (expanded perspective view) which showed the structural example of the mobile electromagnetic drive device (lens drive device) which concerns on embodiment of this invention. It is explanatory drawing (plan view) which showed the structural example of the mobile electromagnetic drive device (lens drive device) which concerns on embodiment of this invention. (A) is a cross-sectional view of A1-A1 in FIG. 2, and (b) is a cross-sectional view of A2-A2 in FIG. It is a top view of the state which the plane board coil is mounted on the base member. It is a partial plan view of FIG. (A) is an RR diagram in FIG. 5, (b) is a sectional view taken along the line SS in FIG. 5, and (c) is a sectional view taken along the line UU in FIG. FIG. 5 is a cross-sectional view taken along the line ZZ in FIG. It is a top view of another embodiment in which a flat substrate coil is mounted on a base member. It is a partial plan view of FIG. FIG. 9A is a sectional view taken along line PP in FIG. 9, and FIG. 9B is a sectional view taken along line QQ in FIG. (A) is a cross-sectional view taken along the line TT in FIG. 9, (b) is a cross-sectional view taken along the line V-V in FIG. 9, and (c) is a perspective view showing a position sensor holding portion on the base member. 9 is a cross-sectional view taken along the line A3-A3 in FIG. It is a cross-sectional view showing the mounting state of the position sensor ((a) is an example of providing a through hole in a flat substrate coil, (b) is an example of providing a recess in a flat substrate coil, and (c) is an example of a flat substrate coil. Example installed above). (A) is an explanatory diagram showing an image pickup device equipped with a mobile electromagnetic drive device (lens drive device), and (b) is a portable electronic device (portable information terminal) equipped with a mobile electromagnetic drive device (lens drive device). It is explanatory drawing which showed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals in different figures indicate parts having the same function, and duplicate description in each figure will be omitted as appropriate.

Here, as an example of the electromagnetic drive device for mobile, a lens drive device will be described as an example, but the present invention is not limited to this, and various types are used as long as a drive coil is attached to the same base member. It can be applied to electromagnetic drive devices. The XY directions shown in the figure refer to directions orthogonal to the optical axis, and the Z direction points to the optical axis direction of the lens (not shown).

As shown in FIGS. 1 to 4, the lens driving device 1 which is an example of the electromagnetic driving device for mobile includes a base member 2 and a movable member 3 movably supported by the base member 2 as a basic configuration. ing. A flat substrate coil 4 is attached to the base member 2, and a magnet 5 is attached to the movable member 3. The flat substrate coil 4 includes a driving coil 4A, and the driving unit of the lens driving device 1 is composed of the coil 4A and the magnet 5. In the illustrated example, the movable member 3 is a cylindrical member having a rectangular outer edge in a plan view, and has a magnet holding portion 3A for holding the magnet 5 inside the corner portion thereof.

The base member 2 has an opening 2A, a support surface 2B along an XY plane is provided around the opening 2A, and a flat substrate coil 4 is supported on the support surface 2B. In the illustrated example, the base member 2 has an outer edge having a rectangular shape in a plan view.

The movable member 3 is supported by the base member 2 via the support wire 6. The support wire 6 extends along the Z direction (optical axis direction) shown in the drawing, one end thereof is fixed to the base member 2 side (wiring member 20 provided on the base member 2), and the other end is movable. It is fixed to the member 3 side (upper leaf spring 9B.9C fixed to the movable member 3). The movable member 3 is suspended and supported by the support wire 6, and is movably supported in the XY directions (direction intersecting the optical axis) due to the bending of the support wire 6. In the illustrated example, a plurality of (4) support wires 6 are provided, one end of the support wire 6 is fixed to the four corners of the base member 2 having a rectangular outer edge in a plan view, and the movable member 5 is movable on the outside thereof. A stopper 2C that limits the range is provided.

The lens frame 7 is movably supported by the movable member 3. The lens frame 7 is a cylindrical member provided with a screw portion 7A to which a lens barrel (not shown) is attached, and a focus coil 8 is wound around a coil holding portion 7B provided on the outer periphery. The lens frame 7 is arranged inside the movable member 3 which is a cylindrical member, and a magnetic gap is formed between the magnet 5 attached to the movable member 3 and the focus coil 8.

The lens frame 7 is movably supported by a leaf spring 9 along the optical axis direction (Z direction in the drawing). The leaf spring 9 includes a lower leaf spring 9A that elastically connects the lower end portion 7C of the lens frame 7 and the lower end portion 3B of the movable member 3, and the upper end portion 7D of the lens frame 7 and the upper end portion 3C of the movable member 3. It is provided with upper leaf springs 9B and 9C that are elastically connected. The upper leaf springs 9B and 9C are composed of two symmetrical members.

The flat substrate coil 4 has a multi-layered insulating layer, and the driving coil 4A is arranged in a plane. The coil 4A may have windings wound in a plane on one insulating layer, or may be wound in multiple stages on a multi-layered insulating layer. Although the flat substrate coil 4 in the present embodiment uses a resin as the insulating layer, the flat substrate coil 4 in the other embodiment is not limited to this, and a film material or the like may be used.

As shown in FIG. 4, the flat substrate coil 4 supported by the base member 2 having a rectangular outer edge is arranged so that the coils 4A are located at the four corners of the base member 2, and the linear portions of the adjacent coils 4A are arranged. They are arranged so that their orientations intersect each other. The four coils 4A are arranged so as to face each of the four magnets 5 attached to the movable member 3.

In the example shown in FIG. 4, the movable frame 3 can be driven in two directions perpendicular to the optical axis by the four coils 4A. That is, the drive unit of the present embodiment has two drive axes Da. The drive shaft Da is a shaft that passes through the center of the thrust generation source and is indicated by the direction in which the movable frame 3 moves when the drive coil 4A is energized. When the coil and the magnet are one, the drive shaft Da passes through the center of the thrust generation source, but when a plurality of coils or magnets are used for the same drive shaft, the direction of the resultant force is driven. It becomes the axis Da.

As shown in FIG. 4, the position sensor 10 is mounted on the flat substrate coil 4. The position sensor 10 detects a change in the magnetic field of the magnet 5 attached to the movable member 3 to detect the moving position of the movable member 3, and a Hall element or the like is used. The position sensor 10 is arranged at a position corresponding to a corner portion of the base member 2 so as to face two of the four magnets 5. In the illustrated example, the two position sensors 10 are arranged at the winding cores of two adjacent coils 4A so that their directions intersect with each other.

The flat substrate coil 4 includes lead-out wirings 11 and 12 drawn from the coil 4A. Of the lead-out wirings 11 and 12, one lead-out wiring 11 is connected to the input terminal portion 13, and the other lead-out wiring 12 is connected in series to each other's coils 4A arranged in parallel. As described above, the magnet 5 drives the movable member and is also used for position detection. Each of the two position sensors 10 is arranged on the drive shaft of the drive unit.
In other embodiments, a dedicated magnet for position detection may be provided, or a magnet provided for a purpose other than driving may be used for position detection.

Further, the flat substrate coil 4 includes a wiring 14 to which the position sensor 10 is connected and a terminal portion 15 as a part of the insulating layer. In the example shown in FIG. 4, the terminal portion 15 is provided at the winding core portion of the coil 4A in the flat substrate coil 4. The wiring 14 connected to the terminal portion 15 extends on the insulating layer of the flat substrate coil 4 and is connected to the concave connection land 16 provided on the peripheral edge of the flat substrate coil 4. By arranging the wiring 14 in an insulating layer different from the layer in which the coil 4A is arranged, the wiring 14 can be arranged at a position that overlaps the coil 4A in a plane.

On the other hand, the base member 2 is provided with the wiring member 20. The wiring member 20 is, for example, a lead frame, and is integrally molded (insert molded) with the resin base member 2. The end portion 20A of the wiring member 20 is drawn out to the outer peripheral portion of the base member 2 and serves as a connection terminal with the circuit board. The wiring member 20 is not limited to the lead frame, and various wiring structures can be adopted. For example, the wiring member 20 may be formed by MID (Molded Interconnect Device) technology. ..

The base member 2 is provided with a terminal protrusion 20P for connecting the wiring member 20 and the flat substrate coil 4. The terminal protrusion 20P can be formed by a part of the wiring member 20 such as a lead frame, or can be formed by projecting a pin-shaped member connected to the wiring member 20 to the support surface 2B. Further, the terminal protrusion 20P can be formed by providing a protrusion on the base member 2 itself and integrally forming the terminal protrusion 20P by MID technology or the like.

The terminal protrusion 20P is provided so as to project from the surface of the base member 2 (for example, the support surface 2B), and the flat substrate coil 4 is side-connected to the terminal protrusion 20P. As a result, a connection structure is formed in which solder does not enter between the flat substrate coil 4 and the support surface 2B.

The connection structure between the terminal protrusion 20P and the flat substrate coil 4 will be described with reference to FIGS. 5 to 7. A part of the terminal protrusion 20P is arranged in the concave connection land 16 provided on the peripheral edge of the flat substrate coil 4. Further, the terminal protrusion 20P is arranged so that the other part penetrates the input terminal portion 13 of the flat substrate coil 4.

As shown in FIGS. 6 and 7, the terminal projection 20P arranged in the input terminal portion 13 or the connection land 16 is connected to the input terminal portion 13 or the connection land 16 from the surface side of the flat substrate coil 4 by the solder 21. Will be done. The solder 21 that enters the hole of the input terminal portion 13 or the recess of the connection land 16 is electrically connected to the side surface of the terminal protrusion 20P and the side surface of the flat substrate coil 4.

As a result, the bottom surface of the flat substrate coil 4 is supported on the support surface 2B of the base member 2 without a gap, which is compared with the connection structure in which solder is interposed between the flat substrate coil 4 and the support surface 2B. , Can be configured thinly. Further, since the soldering work can be performed while visually recognizing the terminal protrusion 20P from the surface side of the flat substrate coil 4, workability is good and reliable connection is possible.

Further, by providing the flat substrate coil 4 with wiring (leading wires 11, 12 and wiring 14) and the terminal portion 15, it is possible to omit the complicated wiring structure and terminal structure of the base member 2. As a result, the base member 2 can be miniaturized, and the coil 4A and the position sensor 10 can be arranged on the miniaturized base member 2 in a space-efficient manner. Since the wiring in the flat substrate coil 4 can be wired in multiple stages using a multi-layered insulating layer, high-density wiring is possible for a narrow surface area. This makes it possible to further reduce the size of the lens driving device 1.

8 to 13 show another example of the connection structure of the position sensor 10. In this example, the flat substrate coil 4 is provided with a terminal portion 17 on the peripheral portion thereof, and the terminal portion 15 to which the position sensor 10 is connected and the terminal portion 17 are connected by wiring 14. The terminal portion 17 is connected to a flexible printed circuit board (FPC) 22. Further, in order to connect the terminal portion 17 of the flat substrate coil 4 and the FPC 22 with the solder 21, the base member 2 is formed with a recess 2D for solder relief.

A recess 2E for solder relief is formed on the support surface 2B of the base member 2 in order to connect the terminal portion 15 of the flat substrate coil 4 and the position sensor 10 with the solder 21. A support protrusion 2F for supporting the position sensor 10 itself is provided in the center of the recess 2E. In order to connect the position sensor 10 to the terminal portion 15, the position sensor 10 is arranged in the opening formed in the winding core portion of the coil 4A in the flat substrate coil 4, and the position sensor 10 is placed on the support projection 2F of the base member 2. In the supported state, it is connected to the terminal portion 15 with solder 21.

In the assembly of the position sensor 10, the flat substrate coil 4 can be supported on the support surface 2B of the base member 2 with the position sensor 10 mounted on the flat substrate coil 4 in advance. As for the mounting state of the position sensor 10 on the flat substrate coil 4, mounting examples as shown in FIGS. 13 (a) to 13 (c) are possible. In the example shown in FIG. 13A, a through hole is provided in the flat substrate coil 4, the position sensor 10 is housed in the through hole, and the connection portion 15 and the terminal of the position sensor 10 are soldered on the back side of the flat substrate coil 4. It is connected by 21. In the example shown in FIG. 13B, a step portion is formed in the thickness direction of the flat substrate coil 4, and the connection portion 15 and the terminal of the position sensor 10 are connected by solder 21 in a state where the position sensor 10 is half-dropped. doing. In the example shown in FIG. 13 (c), the connection portion 15 is provided on the surface of the flat substrate coil 4, and the position sensor 10 is placed on the flat substrate coil 4.
In another example, the terminal portion 15 may be provided in addition to the winding core portion of the coil 4A. That is, the position sensor 10 may be arranged at a position that does not overlap with the coil 4A in a plan view. Then, the terminal portion 15 is provided according to the position of the position sensor 10 arranged in this way.

As described above, in the mobile electromagnetic drive device (lens drive device 1) according to the embodiment of the present invention, the position sensor 10 is connected to a part of the insulating layer of the flat substrate coil 4 supported by the base member 2. Since the wiring 14 and the terminal portion 15 are provided, the driving coil 4A and the position sensor 10 can be deployed on the base member 2 without providing a complicated wiring structure or terminal structure on the base member 2. Space saving of the member 2 is possible. Further, by providing the connecting portion 15 of the position sensor 10 on the flat substrate coil 4, the workability when assembling the position sensor 10 can be improved, and further, the position sensor 10 is mounted on the flat substrate coil 4 in advance. Since it can be assembled to the base member 2, the workability of assembly can be improved.

Such a mobile electromagnetic drive device (lens drive device 1) can be mounted on a small image pickup device 100 as shown in FIG. 14 (a), and is portable as shown in FIG. 14 (b). It can be incorporated into a camera unit of an electronic device (portable information terminal) 200 or the like. Since the mobile electromagnetic drive device incorporated in these can save the space occupied in the incorporated device, it can contribute to the miniaturization and thinning of the image pickup device 100 and the portable electronic device 200.

Further, not only the image pickup device 100 but also the mobile electromagnetic drive device can be equipped with a vibration motor (vibration actuator) using a VCM (VCM: Voice Coil Motor). Further, this vibration motor can be incorporated into a vibration unit of a portable electronic device (portable information terminal) 200.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and the design changes and the like within a range not deviating from the gist of the present invention, etc. Even if there is, it is included in the present invention. Further, each of the above-described embodiments can be combined by diverting the technologies of each other as long as there is no particular contradiction or problem in the purpose and configuration thereof.

1: Lens drive device,
2: Base member, 2A: Aperture, 2B: Support surface,
2C: Stopper, 2D, 2E: Recess, 2F: Support protrusion,
3: Movable member, 3A: Magnet holding part, 3B: Lower end part, 3C: Upper end part,
4: Flat substrate coil, 4A: Coil, 5: Magnet, 6: Support wire,
7: Lens frame,
7A: Threaded part, 7B: Coil holding part, 7C: Lower end part, 7D: Upper end part,
8: Focus coil, 9: Leaf spring, 9A: Lower leaf spring, 9B, 9C: Upper leaf spring,
10: Position sensor, 11, 12: Drawer wiring, 13: Input terminal part,
14: Wiring, 15, 17: Terminal, 16: Connection land,
20: Wiring member, 20A: End, 20P: Terminal protrusion, 21: Solder,
22: Flexible printed circuit board (FPC)
100: Imaging device, 200: Portable electronic device (portable information terminal)

Claims (6)

An electromagnetic drive device for mobile devices
With the base member
A drive coil attached to the base member and
A movable member to which a magnet is attached and movably supported by the base member,
A position sensor provided on the base member and detecting the position of the magnet is provided.
The coil is a flat substrate coil in which windings are arranged in a plane between a plurality of insulating layers, and a part of the insulating layer includes wiring and a terminal portion to which the position sensor is connected .
The position sensor is a mobile electromagnetic drive device, characterized in that the position sensor is assembled to the base member in a state of being previously mounted on the flat substrate coil. The flat substrate coil has a stepped portion formed in the thickness direction.
The position sensor is pre-mounted on the flat substrate coil in a half-dropped state so as to enter the step portion.
The mobile electromagnetic drive device according to claim 1. The position sensor is mounted in advance on the flat substrate coil.
The mobile electromagnetic drive device according to claim 1. The mobile electromagnetic drive device according to any one of claims 1 to 3, wherein the base member has a solder relief recess for connecting the flat substrate coil and the circuit board with solder. An imaging device including the mobile electromagnetic drive device according to any one of claims 1 to 4. A portable electronic device including the mobile electromagnetic drive device according to any one of claims 1 to 4 or the image pickup device according to claim 5.

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