KR20210145088A - Motor for actuating lens - Google Patents

Abstract

An embodiment includes a mover for fixing a lens unit, a stator for moving the mover, and a magnetic unit provided between the mover and the stator, wherein the magnetic unit includes a magnetic material provided on one side of the bobbin; It may include a metal plate provided in the housing to be in contact with the magnetic body.

Description

Lens drive motor {MOTOR FOR ACTUATING LENS}

An embodiment of the present invention relates to a lens driving motor having an improved structure.

As various types of portable terminals are widely distributed and wireless Internet services are commercialized, the demands of consumers related to portable terminals are also diversifying. Accordingly, various types of additional devices are being installed in portable terminals.

Among them, a camera module is a representative that can take a photo or video of a subject, store the image data, and edit and transmit it as needed.

In recent years, the demand for compact camera modules is increasing for use in various multimedia fields such as notebook personal computers, camera phones, PDA, smart devices, toys, etc., and for image input devices such as information terminals of surveillance cameras and video tape recorders. .

A conventional lens driving motor includes an elastic unit such as a coil spring or a leaf spring to provide a return force to the bobbin.

However, the elastic unit occupies a space inside the lens driving motor, thereby reducing the efficiency of component arrangement, and may cause restrictions on the miniaturization of the lens driving motor.

In addition, in the case of an elastic unit implemented as a plate spring, the manufacturing cost increases because the plate spring in the form of a thin plate is easily deformed. .

In addition, the leaf spring has design difficulties in consideration of the elastic modulus according to the weight deformation of the mover.

The embodiment provides a lens driving motor capable of miniaturization, improvement of tilting control performance, simplification of product assembly process, improvement of price, and rapid focus adjustment.

The embodiment provides a lens driving motor including a mover for fixing a lens unit, a stator for moving the mover, and a magnetic unit provided between the mover and the stator.

In addition, the mover may include a bobbin for fixing the lens unit, and a magnet unit provided on the outside of the bobbin.

In addition, the stator may include a coil unit disposed to face the magnet unit, and a housing supporting the coil unit.

In addition, the stator may further include a base for supporting the housing and the mover.

In addition, it may further include a cover can mounted on the base to accommodate the mover and the stator.

In addition, the cover can may be formed of a metal material.

In addition, a fastening piece may be formed in the lower side of the cover can, and a fastening groove or a fastening hole into which the fastening piece is inserted may be formed in the base.

In addition, the magnetic unit may include a magnetic body provided on one side of the bobbin, and a metal plate provided in the housing to be in contact with the magnetic body.

In addition, a magnetic body accommodating groove in which the magnetic body is mounted may be formed on the outer surface of the bobbin.

In addition, at least two or more of the magnetic materials may be disposed on the outer surface of the bobbin at equal intervals.

In addition, the magnetic body may be formed in a cylindrical shape.

In addition, the magnetic body may be provided on the bobbin so that the longitudinal direction of the magnetic body and the optical axis direction of the lens unit coincide.

In addition, a plate receiving groove in which the metal plate is mounted may be formed on the inner surface of the housing.

In addition, the metal plate may be formed of an iron plate.

In addition, the magnet unit may be formed of two opposing magnets, the coil unit may be formed of two coil units, the magnetic material may be provided between the two magnets, and the metal plate may be provided between the two coil units. have.

In addition, it may further include a hall sensor unit disposed to correspond to the magnet unit.

In addition, the hall sensor unit may be provided on the inner surface of the housing.

In addition, the stator may further include a base for supporting the housing and the mover, and the hall sensor unit may be provided on the base.

In addition, the base may be formed with a hall sensor receiving groove in which the hall sensor unit is seated.

In addition, the hall sensor unit may include a hall sensor disposed to correspond to the auxiliary magnet, and a power unit electrically connected to the hall sensor to receive power from the outside.

According to an embodiment of the present invention, it provides a lens driving motor capable of miniaturization, tilting control performance improvement, product assembly process simplification, and price improvement including a magnetic unit, and having a hall sensor unit to enable rapid focus adjustment.

1 is a schematic top view of a lens driving motor according to an embodiment of the present invention;
FIG. 2 is a side cross-sectional view taken along line A-A' in the lens driving motor shown in FIG. 1;
3 is an exploded perspective view of a lens driving motor according to an embodiment of the present invention;

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Unless otherwise specified, all terms herein have the same general meaning as understood by those skilled in the art, and if a term used in this specification conflicts with the general meaning of the term, the definition used herein shall govern.

However, the invention to be described below is only for explaining the embodiments of the present invention, not for limiting the scope of the present invention, and the same reference numbers used throughout the specification indicate the same components. The magnet accommodating groove 112 may be referred to as a first groove and the magnetic body accommodating groove 113 may be referred to as a second groove. The coil unit fastening hole 221 may be referred to as a hole, and the plate receiving groove 222 may be referred to as a third groove.

1 is a schematic top view of a lens driving motor according to an embodiment of the present invention, FIG. 2 is a side cross-sectional view taken along the line A-A' in the lens driving motor shown in FIG. 1, and FIG. 3 is this view An exploded perspective view of a lens driving motor according to an embodiment of the present invention.

1 to 3, the lens driving motor according to the embodiment may include a mover 100 for fixing the lens unit (not shown) and a stator 200 for moving the mover 100. can

Here, the mover 100 may include a bobbin 110 for fixing the lens unit, and a magnet unit 120 provided outside the bobbin 110 .

Specifically, the bobbin 110 is coupled to the lens unit to fix the lens unit, and the coupling method between the lens unit and the bobbin 110 is to attach a screw thread 111 to the inner circumferential surface of the bobbin 110 and the lens unit as shown. A threaded coupling method formed on the outer circumferential surface, respectively, may be used, but may be coupled by a non-threaded method using an adhesive. Of course, even in the screw thread coupling method, it is also possible to achieve a more robust mounting between the bobbin 110 and the lens unit by using an adhesive after the screw thread fastening.

In addition, although the bobbin 110 is illustrated in the shape of an octagonal pillar, it may be implemented in various shapes. The outer peripheral surface of the bobbin 110 may have a magnet accommodating groove 112 recessed in a shape corresponding to the magnet of the magnet part 120 so that a magnet part 120 to be described later can be mounted thereon. These magnet accommodating grooves 112 may be formed continuously along the outer surface of the bobbin 110 or may be formed to be spaced apart from each other at predetermined intervals.

In addition, a magnetic body accommodating groove 113 in which a magnetic body 510 to be described later is mounted may be formed on the outer surface of the bobbin 110 . The magnetic body accommodating groove 113 may be formed by being recessed into a shape corresponding to the magnetic body 510 , and may be formed between the magnet accommodating grooves 112 .

Meanwhile, the lens unit (not shown) may be a lens barrel, and is not limited thereto, and any holder structure capable of supporting the lens may be included. In the embodiment, a case in which the lens unit is a lens barrel will be described as an example. The lens unit is installed on an upper side of a printed circuit board (not shown), which will be described later, and is disposed at a position corresponding to the image sensor. One or more lenses (not shown) are provided in the lens unit.

The magnet part 120 may be mounted on the bobbin 110 so as to be disposed on the outer surface of the bobbin 110 , and may be inserted into the magnet accommodating groove 112 as shown, or the magnet accommodating groove. It can be mounted on 112 with an adhesive or the like. Although the magnet unit 120 is illustrated as two opposing magnets, four magnets may be mounted on the outer surface of the bobbin 110 at equal intervals. The four magnets may be first to fourth magnets.

The shape of each of the magnets constituting the magnet unit 120 may be formed in a rectangular plate shape as shown, but unlike this, a triangular prism shape in which the inner surface forms a curved surface according to the structural change of the bobbin 110, It may be formed in each column shape, such as a rectangular column shape or a trapezoidal column shape.

Meanwhile, the stator 200 may include a coil unit 210 disposed to face the magnet unit 120 , and a housing 220 supporting the coil unit 210 , and the housing 220 . and a base 230 supporting the mover 100 may be further included.

As shown in FIG. 3 , the side plate of the cover can 300 includes a first side plate and a second side plate disposed opposite to each other, and a third side plate and a second side plate that connect the first side plate and the second side plate and are disposed on opposite sides of each other. It may include 4 side plates. In this case, the coil unit 210 may include a first coil disposed at a position corresponding to the first side plate and a second coil disposed at a position corresponding to the second side plate. The magnet unit 120 may include a first magnet facing the first coil and a second magnet facing the second coil. Although the coil unit 210 is illustrated as being formed as two wound coil units 210 , it may be provided to correspond to the magnet unit 120 as described above. That is, if the magnet unit 120 is formed of four magnets, four individual coils may be disposed toward the magnet unit 120 . The coil unit 210 may form an electromagnetic field by receiving power applied from a printed circuit board, which will be described later. Accordingly, the four coils may receive power individually from the printed circuit board. The four coils include a first coil disposed at a position corresponding to the first side plate, a second coil disposed at a position corresponding to the second side plate, a third coil disposed at a position corresponding to the third side plate; It may include a fourth coil disposed at a position corresponding to the fourth side plate.

The housing 220 may be formed in a shape corresponding to the inner surface of the cover can 300 to be described later. In an embodiment, the housing 220 may be formed and disposed in a hexahedral shape to correspond to the shape of the cover can 300 , and the upper and lower sides may be opened to support the mover 100 .

In addition, the housing 220 may include a coil unit fastening hole 221 or a coil unit fastening groove formed in a shape corresponding to the coil unit 210 on the side surface, and the inner surface of the housing 220 has A plate receiving groove 222 in which the metal plate 520 is mounted may be formed. The coil unit 210 or the metal plate 520 may be more firmly mounted to the housing 220 using an adhesive or the like.

In addition, the housing 220 has at least two stoppers 223 formed at equal intervals on the upper side thereof, so as to absorb the impact by contacting the upper side surface of the cover can 300 for external impact to absorb the impact. can protect

In addition, the housing 220 is formed of an insulating material, and may be made as an injection molded product in consideration of productivity, and the bobbin 110 is a moving part for auto-focusing (AF) driving and is at a predetermined distance from the cover can 300 . They may be spaced apart.

The base 230 is disposed below the lens driving motor to support the housing 220 and the mover 100 .

Specifically, the base 230 supports the stator 200 and the mover 100, and has a circular shape in the center so that the bobbin 110 can be positioned to be spaced apart, and the recess 231 recessed downward. ) is formed, and a hall sensor accommodating groove 232 in which a hall sensor unit to be described later is seated may be formed on the side of the recess 231 , and a through hole corresponding to an image sensor (not shown) to be described later in the center may be formed. (233) is formed.

The base 230 may function as a sensor holder to protect the image sensor, and the through hole 233 may be provided to position a filter (not shown).

In this case, the filter may be provided with an infrared filter (Infrared Ray Filter). In addition, the filter may be formed of, for example, a film material or a glass material, and an infrared blocking coating material may be disposed on a plate-shaped optical filter such as a cover glass for protecting an imaging surface or a cover glass. In addition, a separate sensor holder may be positioned under the base 230 in addition to the base 230 .

In addition, the base 230 may be formed with one or more fixing protrusions 234 that protrude from the upper corner to face or combine with the inner surface of the housing 220, and these fixing protrusions 234 are formed on the housing ( 220) to easily guide the fastening and at the same time make it possible to achieve a firm fixation after fastening.

In addition, although not shown, the base 230 may have a fastening groove (not shown) into which the fastening piece 310 of the cover can 300 to be described later is inserted. This fastening groove is formed locally on the outer surface of the base 230 in a shape corresponding to the length of the fastening piece 310 or a predetermined portion of the lower end of the cover can 300 including the fastening piece 310 is inserted. It may be formed entirely on the outer surface of the base 230 so that the

In addition, a concave terminal groove 235 may be formed in the side portion of the base 230 to correspond to the shape of the terminal portions 411 and 421 to be described later.

Meanwhile, the embodiment may further include a cover can 300 mounted on the base 230 to accommodate the mover 100 and the stator 200 .

The cover can 300 forms the exterior of the lens driving motor, and an opening formed so that the lens unit can be opened is formed on the upper side thereof, and the lower side thereof can be formed as an open surface that is all open.

Specifically, the cover can 300 is mounted on the base 230 in close contact with the side surface of the base 230, which will be described later, and protects internal components from external impacts and prevents penetration of external contaminants. have a function

In addition, the cover can 300 should also perform a function of protecting the components of the camera module from external interference generated by a mobile phone or the like. Accordingly, the cover can 300 may be formed of a metal material.

In addition, the cover can 300 has at least one fastening piece 310 extending on each side of the lower end is formed, and the base 230 has a fastening groove into which the fastening piece 310 is inserted. (not shown) or a fastening hole is formed to implement a more robust sealing function and fastening function of the camera module.

The embodiment may further include a terminal 400 electrically connected to the coil unit 210 to supply power from a printed circuit board to be described later to the coil unit 210 . The terminal 400 may be disposed on the upper surface of the base 230 , and may be electrically connected to the coil unit 210 by a soldering method. The terminal 400 may be formed of two metal materials 410 and 420 in a mutually symmetrical shape, and one end of each terminal 400 is bent to form a terminal groove 235 on the side of the base 230 . It may include terminal portions 411 and 421 disposed on the .

Here, the embodiment includes the magnetic unit 500 provided between the mover 100 and the stator 200 . Specifically, the magnetic unit 500 includes a magnetic body 510 provided on one side of the bobbin 110 and a metal plate 520 provided on the housing 220 so as to be in contact with the magnetic body 510 . can do.

Since the magnetic material 510 and the metal plate 520 can hold the bobbin 110 at a specific position in a space spaced apart from the bobbin 110 and the housing 220 by mutual attraction, the bobbin ( The additional power of the lens driving motor applied so that the 110 is continuously positioned is unnecessary, and the vibration prevention function of the bobbin 110 is improved. In addition, since the existing elastic unit is unnecessary, efficient use of the inner space of the lens driving motor can be promoted, and thus the overall size of the lens driving motor can be reduced.

The magnetic body 510 may be formed of a magnet, and at least two or more may be provided on the outer surface of the bobbin 110 at equal intervals, and provided between the magnet parts 120 as shown. It is mounted on the magnetic body accommodating groove 113 with an adhesive or the like so as to be able to achieve a stable holding function of the bobbin 110 .

In addition, the magnetic body 510 may be formed in various shapes, but since contacting the metal plate 520 with a minimum area is efficient in terms of power of the lens driving motor, it is formed in a spherical shape or a cylindrical shape as shown. can be In the latter case, the magnetic body 510 may be provided on the bobbin 110 so that the longitudinal direction of the magnetic body 510 and the optical axis direction of the lens unit coincide with each other to facilitate movement of the lens unit in the optical axis direction. That is, the magnetic body 510 may be a spherical ball. As shown in FIG. 2 , the magnetic material 510 may be disposed on the surface of the metal plate 520 . The magnetic body 510 may move along the surface of the metal plate 520 .

The metal plate 520 may be formed of a metal material that reacts with the magnetic material 510 , for example, an iron plate. Of course, the magnetic material 510 may be formed in a plate shape so that an area in contact with the magnetic material 510 may be minimized, and the metal plate 520 may be formed in a cylindrical shape or the like.

Such a metal plate 520 may be provided between the two coil parts 210 as shown, and can be firmly mounted with an adhesive or the like in the plate receiving groove 222 formed in the housing 220 as described above. can

On the other hand, the embodiment further includes a hall sensor unit (not shown) disposed to correspond to the magnet unit 120 to detect and feed back the position information of the mover 100 to realize faster and more accurate lens driving. have.

Specifically, the Hall sensor unit is provided to precisely control the mover 100 by sensing the movement of the magnet unit 120 , and one or more Hall sensor units may be provided.

Since the hall sensor unit only needs to correspond to the magnet unit 120 , it may be provided on the inner surface of the housing 220 or provided on the base 230 . In the latter case, as described above, the hall sensor accommodating groove 232 is formed in the base 230 to effectively arrange the space of the hall sensor unit. In the former case, the Hall sensor unit is adjacent to the coil unit 210, but considering that the strength of the magnetic field formed in the magnet is several hundred times greater than the strength of the electromagnetic field formed in the coil unit 210, the magnet unit ( The influence of the coil unit 210 in detecting the movement of the 120 is not considered.

The hall sensor unit may include a hall sensor disposed to correspond to the magnet unit 120 and a power unit electrically connected to the hall sensor to receive power from the outside. The power unit may receive external power from a printed circuit board (not shown), etc., which will be described later. When disposed on the upper surface of the base 230 , the power unit is provided on the base 230 with a separate flexible printed circuit board (FPCB). , not shown) to receive power.

On the other hand, the lens driving motor according to the embodiment may be mounted on a camera module, and such a camera module is a mobile phone or a notebook personal computer, a camera phone, PDA, smart, a variety of multimedia fields such as toys (toy), and further monitoring It may be provided in an image input device such as an information terminal of a camera or a video tape recorder.

In other words, when the lens driving motor according to the embodiment is provided in the camera module, the camera module is not shown, but may further include a printed circuit board (not shown) and an image sensor (not shown).

The image sensor may be mounted on the central portion of the upper side of the printed circuit board, and various elements (not shown) for driving the camera module may be mounted. In addition, the printed circuit board is electrically connected to the terminal parts 411 and 421 of the terminal 400 or the coil part 210 directly to apply power for driving the lens driving motor according to the embodiment. .

The image sensor (not shown) may be mounted on the central portion of the upper side of the printed circuit board so as to be positioned along the optical axis direction with one or more lenses (not shown) accommodated in the lens unit. Such an image sensor converts an optical signal of an object incident through a lens into an electrical signal.

The adhesive described above may be implemented as a thermosetting epoxy or UV epoxy, and is cured by exposure to heat or UV. However, when a thermosetting epoxy is used, it is cured by moving to an oven or by applying direct heat, and when using a UV (ultraviolet) epoxy, it is a method of curing by applying UV (ultraviolet rays) to the adhesive.

In addition, the adhesive may be an epoxy in which heat curing and UV (ultraviolet ray) curing can be mixed, and both thermal curing and UV (ultraviolet ray) curing are possible, so it may be an epoxy that can be cured by selecting any one of them. The adhesive is not limited to the epoxy, and any material that can be adhered to may be substituted.

Above, those skilled in the art from the above description will know that various changes and modifications are possible without departing from the technical spirit of the present invention. It should be determined by the scope and its equivalent scope.

100: mover 110: bobbin
112: magnet accommodating groove 113: magnetic body accommodating groove
120: magnet part 200: stator
210: coil unit 220: housing
221: coil part fastening hole 222: plate receiving groove
230: base 231: recessed portion
232: hall sensor receiving groove 300: cover can
400: terminal 500: magnetic unit
510: magnetic material 520: metal plate

Claims (20)

a cover can comprising a top plate and a side plate extending from the top plate;
a bobbin disposed in the cover can;
a housing disposed between the cover can and the bobbin;
a magnet disposed on the bobbin;
a coil disposed between the magnet and the side plate of the cover can;
a metal plate disposed on the housing; and
and a spherical ball disposed between the bobbin and the housing,
The ball is a lens driving motor disposed on the surface of the metal plate. According to claim 1,
The ball is a lens driving motor that moves along the surface of the metal plate. According to claim 1,
The ball is a lens driving motor in contact with the metal plate. According to claim 1,
The side plate of the cover can includes a first side plate and a second side plate disposed opposite to each other,
The coil includes a first coil disposed between the bobbin and the first side plate, and a second coil disposed between the bobbin and the second side plate,
wherein the magnet includes a first magnet facing the first coil and a second magnet facing the second coil. 5. The method of claim 4,
The side plate of the cover can includes a third side plate and a fourth side plate that connect the first side plate and the second side plate and are disposed opposite to each other,
The coil includes a third coil disposed between the bobbin and the third side plate, and a fourth coil disposed between the bobbin and the fourth side plate,
wherein the magnet includes a third magnet facing the third coil and a fourth magnet facing the fourth coil. 6. The method of claim 5,
The first to fourth coils are individually powered lens driving motors. According to claim 1,
The bobbin includes a first groove and two second grooves formed on an outer circumferential surface of the bobbin,
The magnet is disposed in the first groove of the bobbin,
The ball is a lens driving motor disposed in the two second grooves. 8. The method of claim 7,
The first groove of the bobbin is a lens driving motor disposed between the two second grooves. According to claim 1,
The ball and the metal plate are not disposed on an imaginary straight line connecting the magnet and the coil. According to claim 1,
The ball is a lens driving motor formed of a magnetic material. According to claim 1,
The housing includes a portion having a shape corresponding to the shape of at least a portion of the metal plate,
The metal plate is a lens driving motor coupled to the housing by an adhesive. According to claim 1,
The housing includes a hole penetrating the housing in a direction perpendicular to the optical axis direction,
The coil is a lens driving motor disposed in the hole of the housing. 9. The method of claim 8,
The housing includes an inner peripheral surface facing the outer peripheral surface of the bobbin,
The housing includes a third groove formed on the inner peripheral surface of the housing,
The ball is disposed between the second groove of the bobbin and the third groove of the housing,
The second groove of the bobbin and the third groove of the housing are formed in different shapes from each other. According to claim 1,
It includes a hall sensor disposed to correspond to the magnet,
The hall sensor detects the position information of the bobbin,
The hall sensor is a lens driving motor disposed adjacent to the coil. 15. The method of claim 14,
A lens driving motor comprising a flexible printed circuit board (FPCB) on which the hall sensor is mounted. Base;
a housing disposed on the base;
a bobbin disposed within the housing;
a magnet disposed on the bobbin;
a coil interacting with the magnet;
a metal plate disposed on the housing; and
and a spherical ball disposed between the bobbin and the housing,
The ball is a lens driving motor arranged to move along the surface of the metal plate. 17. The method of claim 16,
The ball is a lens driving motor in contact with the metal plate. printed circuit board;
an image sensor disposed on the printed circuit board;
The lens driving motor of any one of claims 1 to 17 disposed on the printed circuit board; and
and a lens coupled to the bobbin of the lens driving motor and disposed at a position corresponding to the image sensor. A mobile terminal comprising the camera module of claim 18 . a cover can comprising a top plate and a side plate extending from the top plate;
a bobbin disposed in the cover can;
a housing disposed between the cover can and the bobbin;
a magnet disposed on the bobbin; and
A lens driving motor including a coil disposed between the magnet and the side plate of the cover can.

Images