KR102489147B1 - Motor for actuating lens - Google Patents

Abstract

The embodiment includes a bobbin for fixing the lens unit, a mover including a coil unit provided outside the bobbin, a first magnet unit disposed to face the coil unit, a yoke unit supporting the first magnet unit, and the yoke. Provided is a lens driving motor including a stator including a base supporting the unit and the mover, a second magnet unit provided on one side of the bobbin, and a hall sensor unit disposed to correspond to the second magnet unit.

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

Among them, a typical camera module is capable of taking a picture or video of a subject, storing the image data, and then editing and transmitting the image data as needed.

Recently, the demand for small camera modules is increasing for various multimedia fields such as notebook-type personal computers, camera phones, PDAs, smart phones, and toys, and image input devices such as information terminals for surveillance cameras and video tape recorders. .

In the conventional camera module, when the mover is driven, electromagnetic force is destabilized due to attractive or repulsive force between the magnet and the cover can made of metal, and thus linearity may be deteriorated.

In addition, since the user positions the camera module in various directions when manipulating the camera module, due to the nature of the magnet part located on the mover having a relatively heavy weight, the positional difference (in particular, due to gravity) increases, resulting in eccentricity of the lens part. There is a concern that the performance of the camera module may deteriorate, such as this occurs.

In addition, when the magnet unit is disposed on the mover, the coil unit is disposed on the stator, but it is difficult to firmly mount the coil unit on the stator due to its relatively flexible physical properties.
(Patent Document 1) JP 2012-027433 A

The embodiment provides a lens driving motor capable of driving accurately and quickly.

The embodiment includes a bobbin for fixing the lens unit, a mover including a coil unit provided outside the bobbin, a first magnet unit disposed to face the coil unit, a yoke unit supporting the first magnet unit, and the yoke. Provided is a lens driving motor including a stator including a base supporting the unit and the mover, a second magnet unit provided on one side of the bobbin, and a hall sensor unit disposed to correspond to the second magnet unit.

In addition, the hall sensor unit may be provided on an inner surface of the yoke unit or may be provided on the base.

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

In addition, the hall sensor unit may be provided at a lower portion of an inner surface of the yoke unit, and a terminal groove portion corresponding to the terminal unit may be formed on an end surface of the yoke unit so that the terminal unit is exposed to the outside.

In addition, the second magnet part may be formed in a size that does not affect the magnetic flux density of the first magnet part corresponding to the electromagnetic force driving the coil part.

In addition, the second magnet part may be provided on a lower surface of the bobbin.

In addition, at least one or more magnetic materials mounted on the first magnet and interviewing the coil may be further included between the first magnet and the coil.

In addition, two magnetic materials may be mounted to face each other on an inner surface of the first magnet part.

In addition, the yoke portion may be implemented as a cover can made of a metal material.

According to the embodiment of the present invention, performance degradation due to movement of the mover can be minimized by providing the second magnet unit, and excellent focus correction is possible due to less restrictions on the arrangement of the hall sensor unit.

1 is a schematic side view of a lens driving motor according to an embodiment of the present invention;
2 is a perspective view of a lens driving motor according to an embodiment of the present invention;
3 is a perspective view showing a yoke part removed from the lens driving motor of FIG. 2;
4 is an exploded perspective view of a lens driving motor according to an embodiment of the present invention;
5 is a view of a stator according to an embodiment of the present invention viewed from a lower side;

1 is a schematic side view of a lens driving motor according to an embodiment of the present invention.

Referring to FIG. 1 , the lens driving motor according to the embodiment winds the coil unit 120 instead of the relatively heavy first magnet unit 210 in the bobbin 110 fixing the lens unit 10, and the second magnet unit ( 300) is mounted on the bobbin 110, and the image focus can be adjusted by performing an accurate and quick feedback action with the hall sensor unit 400.

In addition, the lens driving motor according to the embodiment includes the magnetic body 500 to prevent eccentricity of the mover 100 and secure the function of the elastic unit, so that the lens driving motor with improved reliability can be implemented.

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

Unless otherwise defined, all terms in this specification 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 in this specification shall apply.

However, the invention to be described below is not intended to limit the scope of the present invention only for explaining the embodiments of the present invention, and the same reference numerals used throughout the specification indicate the same components.

2 is a perspective view of a lens driving motor according to an embodiment of the present invention, FIG. 3 is a perspective view of the lens driving motor of FIG. 2 in which the yoke part 220 is removed, and FIG. 4 is a lens driving motor according to an embodiment of the present invention. It is an exploded perspective view of , and FIG. 5 is a view of the stator 200 according to an embodiment of the present invention viewed from the lower side.

Referring to FIGS. 2 to 5 , the lens driving motor according to the embodiment may largely include a mover 100 and a stator 200 .

Here, the mover 100 may include a bobbin 110 and a coil unit 120 .

delete

The bobbin 110 is coupled to the lens unit 10 to fix the lens unit 10, and the coupling method between the lens unit 10 and the bobbin 110 is the thread 111 as shown in the bobbin ( 110) and the outer circumferential surface of the lens unit 10 may be respectively formed using a threaded coupling method, or may be coupled by a non-threaded method using an adhesive. Of course, even in the screw thread coupling method, after screw thread coupling, an adhesive may be used to more firmly mount the bobbin 110 and the lens unit 10 to each other.

In addition, a guide part 112 may be formed on an outer circumferential surface of the bobbin 110 to guide winding or mounting of the coil part 120 to be described later. The guide part 112 may be integrally formed with the outer surface of the bobbin 110, and may be formed continuously along the outer surface of the bobbin 110 or spaced apart at predetermined intervals.

In addition, on the upper and / or lower side of the bobbin 110, a fastening protrusion to which an upper spring and / or a lower spring provided so that the bobbin 110 can be supported on the upper side of the base 230, which will be described later, are fastened ( 113) can be formed.

In addition, the bobbin 110 includes a concave portion 114 formed on an outer circumferential surface so that the yoke portion 220 to be described later can be positioned between the bobbin 110 and the coil portion 120 wound on the bobbin 110. can include more.

Meanwhile, the lens unit 10 may be a lens barrel, but is not limited thereto, and may include any holder structure capable of supporting a lens. In the embodiment, a case in which the lens unit 10 is a lens barrel will be described as an example. The lens unit 10 is installed on the upper side of a printed circuit board (not shown) to be described later, and is disposed at a position corresponding to an image sensor. The lens unit 10 includes one or more lenses (not shown).

The coil part 120 may be guided by the guide part 112 and wound on the outer surface of the bobbin 110, but four individual coils may be disposed on the outer surface of the bobbin 110 at 90° intervals. may be The coil unit 120 may form an electromagnetic field by receiving power applied from a printed circuit board to be described later.

Meanwhile, the stator 200 may include a first magnet part 210 , a yoke part 220 and a base 230 .

The first magnet part 210 is mounted on the yoke part 220 so as to be disposed at a position corresponding to the outer surface of the coil part 120, and as shown, inside the yoke part 220 4 It is mounted on the corners of the dog at equal intervals to promote efficient use of the internal volume.

The shape of each of the magnets constituting the first magnet part 210 may be formed in a triangular prism shape with an inner surface forming a curved surface as shown, but, unlike this, a square prism shape or a trapezoidal prism shape according to internal structural changes. It may also have a columnar shape.

The yoke part 220 forms the outer appearance of the lens driving motor, has an opening formed on its upper side with a larger diameter than the diameter of the bobbin 110, and has an open lower side formed as an open surface. Here, a magnet fixing part 222 bent downward to fix the first magnet part 210 may be formed in the opening, and a terminal part 420 of a hall sensor part 400, which will be described later, may be formed on a side surface to the outside. A terminal groove portion 223 corresponding to the terminal portion 420 may be formed on the end surface so as to be exposed.

The yoke part 220 accommodates the elastic unit, the mover 100, and the stator 200, which will be described later, and is mounted on the base 230 to form the appearance of the camera module. Specifically, the inner surface of the yoke part 220 is mounted on the base 230 in close contact with the side surface of the base 230 to be described later, and protects internal components from external impact and at the same time prevents penetration of external contaminants. has a function

In addition, the yoke part 220 should also perform a function of protecting components of the camera module from external radio wave interference generated by a mobile phone or the like. Accordingly, the yoke portion 220 may be implemented as a cover can made of a metal material.

In addition, although not shown, the yoke part 220 has at least one extending fastening piece formed on each surface of the lower end, and a fastening groove into which the fastening piece is inserted is formed in the base 230 to make the camera module more robust. A sealing function and a fastening function can be implemented.

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

Specifically, the base 230 supports the stator 200 and the mover 100, and has a recessed recess 231 recessed downward in a circular shape at the center so that the bobbin 110 can be spaced apart from each other. ) is formed, and a seating groove 231a in which the hall sensor unit 400 to be described later is seated may be formed on the side of the recess portion 231, and a through hole corresponding to the lens unit 10 is formed in the center. (231b) is formed.

The base 230 may function as a sensor holder to protect an image sensor (not shown) to be described later, and the through hole may be provided to position a filter (not shown). In this case, the filter may include an 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 or the like may be disposed on a flat optical filter such as a cover glass for protecting an imaging surface or a cover glass. In addition, a separate sensor holder may be additionally located under the base 230 in addition to the base 230 .

In addition, the base 230 may be formed with one or more fixing protrusions 232 that protrude from the upper edge and face or combine with the inner surface of the yoke part 220, and these fixing protrusions 232 are formed on the yoke It guides the fastening of the part 220 easily and at the same time makes it possible to secure it firmly after fastening.

In addition, a fastening protrusion 233 to which a lower spring to be described later is fastened may be formed on an upper surface of the base 230 .

In addition, although not shown, the base 230 may be formed with a fastening groove into which the fastening piece of the yoke part is inserted. These fastening grooves are locally formed on the outer surface of the base 230 in a shape corresponding to the length of the fastening piece, or the outer surface of the base 230 so that a predetermined portion of the lower end of the cover can including the fastening piece can be inserted. can be formed entirely in

On the other hand, in the embodiment, the second magnet part 300 and the hall sensor part 400 are included to detect and feed back the positional information of the mover 100, so that more rapid and accurate lens driving can be realized.

The second magnet part 300 is provided on one side of the bobbin 110 . Here, one side means a part of the side part of the bobbin 110, and as shown in FIG. 1, it may be inserted into the inside of the lower side of the bobbin 110, and the bobbin 110 may be inserted into the upper, lower, or center of the bobbin 110. It means that it is mounted by forming a groove in As shown in FIGS. 3 and 5 , the second magnet part 300 is disposed on the outer circumferential surface of the bobbin 110 so that at least a portion of the coil part 120 is disposed between the second magnet part 300 and the Hall sensor 410 . It can be placed in the groove 115 formed in. As shown in FIG. 3 , the lower end of the second magnet part 300 may be disposed lower than the lower end of the coil part 120 .

The second magnet part 300 is formed in a size that does not affect the magnetic flux density of the first magnet part 210 corresponding to the electromagnetic force that drives the coil part 120, and thus affects the function of the mover 100. It can be formed to a size that does not affect it. Accordingly, the second magnet part 300 may be formed as a hall sensor magnet or an auxiliary magnet having a smaller size than the first magnet part. Although the size of the second magnet part 300 is 1/5 smaller than the individual magnets of the first magnet part 210, it does not affect the magnetic force of the first magnet part 210. Since it can be implemented in size, it may be implemented in a size smaller than 1/5 or larger than 1/5 of the individual magnets of the first magnet part 210 .

In the embodiment, since the coil part 120 can be disposed on the mover 100 instead of the first magnet part 210 by having such a second magnet part 300, the mover 100 can be reduced in weight. In this mover 100, the eccentricity of the lens unit 10 can be reduced no matter where the user directs the camera module, and also, the light-weight mover 100 can be quickly and precisely controlled and the hall sensor unit (400) In the arrangement structure, it is possible to use the internal structure more freely than the conventional lens drive boat.

Meanwhile, the hall sensor unit 400 is provided to precisely control the mover 100 by detecting the movement of the second magnet unit 300, and the hall sensor unit 400 is provided with one or more. It can be.

Although the hall sensor unit 400 is provided closer to the coil unit 120 than the second magnet unit 300, 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 , the influence of the coil unit 120 in detecting the movement of the second magnet unit 300 is not considered.

It is arranged to correspond to the second magnet part 300, and is disposed below the second magnet part 300 as shown in FIG. 1, or as shown in FIG. 2 or 5, the second magnet part It can be arranged outside of (300).

In the former case, as shown in FIG. 4 , the hall sensor unit 400 may be seated in the seating groove 231a of the recess 231 formed in the base 230, and in the latter case, FIG. 2 And as shown in FIG. 5 , the hall sensor unit 400 may be provided on an inner surface of the yoke unit 220 .

The Hall sensor unit 400 includes a Hall sensor 410 disposed to correspond to the second magnet unit 300 and a terminal unit 420 that is electrically connected to the Hall sensor 410 and receives power from the outside. include Referring to FIG. 5 , when the hall sensor part 400 is disposed on the side of the yoke part 220, the terminal part 420 is exposed to the terminal groove part 223 formed on the end surface of the yoke part 220, When external power is applied from a printed circuit board (not shown), etc., and the hall sensor unit 400 is disposed on the upper surface of the base 230 as shown in FIG. 1, the terminal unit 420 is connected to the base 230 may be mounted on a separate Flexible Printed Circuit Board (FPCB, not shown) to receive power.

In addition, although not shown, the driving unit according to the embodiment of the present invention may further include an elastic unit.

The elastic unit includes an upper spring and a lower spring.

The upper spring and the lower spring may be formed of separate springs disposed on each side of the housing, but for efficiency of production, it is preferable that a single plate material be formed in a bent and cut shape.

The upper spring is fastened to the upper surface of the yoke part 220 and the upper surface of the bobbin 110 to support the bobbin 110, and to provide a return force when the bobbin 110 moves upward, the yoke part 220 is provided at the upper end of Specifically, the upper spring is disposed at the upper end of the yoke part 220 and protrudes to a predetermined width in an inner circumferential direction from an opening formed at the upper end, and the protruding portion supports the upper end of the bobbin 110.

Here, since the yoke part 220 may be formed of a metal material, an insulating plate 224 made of an insulating material may be provided between the yoke part 220 and the upper spring. In addition, a cover 225 formed in a shape corresponding to the upper side of the yoke part 220 may be mounted on an upper end of the upper spring.

Upper surfaces of the cover 225, the upper spring, the insulating plate 224, and the yoke portion 220 may have holes corresponding to each other, and may be fastened with an adhesive or the like.

The rim side of the lower spring is supported on the upper surface of the base 230, and the lower end side of the bobbin 110 is supported on the inner circumferential side. Specifically, the lower spring is formed of two corresponding leaf springs and is electrically connected to one end and the other end of the coil part 120 wound on the bobbin 110, respectively, so that power can be transmitted to the coil part 120. there is. That is, the lower spring may be formed as a leaf spring in a shape symmetrical about the optical axis, and is preferably formed as a separate leaf spring for input and output of power.

Of course, the upper spring may be formed in the shape of the lower spring as shown.

Meanwhile, the embodiment may further include a magnetic body 500 provided separately or together with the elastic unit. The magnetic body 500 is mounted on the first magnet part 210 and positioned between the first magnet part 210 and the coil part 120, and interviews the coil part 120 to form the mover 100. ) provides frictional force for the movement of

The magnetic body 500 may be formed of a metal material such as an iron plate so as to be attached to the first magnet unit 210, and the magnetic body 500 is formed between the coil unit 120 and the first magnet unit 210. By supporting the spaced-apart space, it is possible to reduce a posture difference (bleaching of the mover 100) due to a change in the position of the lens driving motor. Therefore, it is preferable that two or more of these magnetic materials 500 are mounted to face each other on the inner surface of the first magnet part 210 .

Therefore, the posture difference of the lens driving motor is reduced by the magnetic material 500, and continuous power supply to the coil unit is unnecessary to maintain the lens unit in a specific position. In addition, since the magnetic material 500 also performs the function of an elastic unit, a lens driving motor can be implemented without a separate elastic unit, thereby miniaturizing the optical axis direction and efficiently operating the internal space.

On the other hand, the lens driving motor according to the embodiment may be mounted on a camera module, and this camera module is used in a variety of multimedia fields such as mobile phones or notebook personal computers, camera phones, PDAs, smart devices, toys, and even surveillance It can be provided in an image input device such as a camera or an information terminal of a video tape recorder.

In short, when the lens driving motor according to the embodiment is provided in the camera module, the camera module, although not shown, 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 a camera module may be mounted. In addition, the printed circuit board is electrically connected to the terminal unit 420 or the lower spring or upper spring or directly to the coil unit 120 in order 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 surface of the printed circuit board to be positioned along an optical axis direction with one or more lenses (not shown) accommodated in the lens unit 10 . Such an image sensor converts an optical signal of an object incident through a lens into an electrical signal.

The aforementioned adhesives may be implemented as thermosetting epoxies or UV epoxies, and are cured by exposure to heat or UV. However, if a thermosetting epoxy is used, it is a method of curing by moving to an oven or by directly applying heat, and if a UV (ultraviolet ray) epoxy is used, it is a method of curing by applying UV (ultraviolet rays) to the adhesive.

In addition, the adhesive may be an epoxy capable of both thermal curing and UV (ultraviolet ray) curing, and may be an epoxy capable of both thermal curing and UV (ultraviolet ray) curing, and may be cured by selecting one of the two. The adhesive is not limited to the epoxy, and any adhesive material can be substituted.

As described above, those skilled in the art will know that various changes and modifications are possible without departing from the technical spirit of the present invention, and the technical scope of the present invention is not limited to the contents described in the embodiments, but claims It must be determined by the scope and its equivalent scope.

100: mover 110: bobbin
120: coil unit 200: stator
210: first magnet part 220: yoke part
230: base 300: second magnet part
400: hall sensor unit 500: magnetic body

Claims (20)

Base;
a cover can including a top plate and a side plate extending from the top plate and disposed on the base;
a bobbin disposed within the cover can;
a coil disposed on an outer circumferential surface of the bobbin;
a first magnet disposed between the coil and the side plate of the cover can;
a second magnet disposed on the bobbin;
a circuit board disposed on the side plate of the cover can; and
A sensor disposed on the circuit board and detecting the position of the bobbin through the second magnet;
A part of the coil is disposed between the second magnet and the sensor,
The bobbin includes a first groove in which the second magnet is disposed,
At least a part of the second magnet is disposed between the bobbin and the coil. According to claim 1,
The first magnet moves the bobbin in the optical axis direction through interaction with the coil, and the second magnet is a sensing magnet that is spaced apart from the first magnet and detects the position of the bobbin. According to claim 1,
The second magnet includes a first region overlapping with the coil in a direction perpendicular to an optical axis and a second region that does not overlap. delete According to claim 1,
The circuit board includes a terminal unit,
The cover can includes a terminal groove portion formed at a lower end of the side plate of the cover can to expose the terminal portion. According to claim 5,
The circuit board is a flexible printed circuit board (FPCB), and a lens driving motor is partially disposed on a side surface of the base. According to claim 1,
The circuit board is a lens driving motor disposed on an inner surface of the side plate of the cover can. According to claim 5,
The first magnet includes a plurality of unit magnets spaced apart from each other,
The second magnet has a size of 1/5 or less of the size of one of the plurality of unit magnets. According to claim 5,
a lower spring connecting the bobbin and the base; and
A lens driving motor comprising an upper spring coupled to the bobbin and disposed above the lower spring. According to claim 1,
The coil moves the bobbin in the optical axis direction through interaction with the first magnet,
The sensor is a lens driving motor including a hall sensor. delete Base;
a cover can including a top plate and a side plate extending from the top plate and coupled to the base;
a bobbin disposed within the cover can;
a coil disposed on an outer circumferential surface of the bobbin;
a first magnet disposed within the cover can and facing the coil;
a second magnet disposed on the bobbin;
a circuit board disposed on the side plate of the cover can; and
A sensor disposed on the circuit board and detecting the position of the bobbin;
The circuit board includes a terminal unit,
The side plate of the cover can includes an opening exposing the terminal portion. According to claim 12,
A part of the second magnet is disposed between the outer circumferential surface of the bobbin and the coil,
One side surface of the second magnet includes a first area facing the coil and a second area exposed to the outside of the coil. According to claim 13,
The bobbin includes a groove formed on the outer circumferential surface of the bobbin,
The second magnet is disposed in the groove of the bobbin. printed circuit board;
an image sensor disposed on the printed circuit board;
a lens driving motor according to any one of claims 1 to 3, 5 to 10, and 12 to 14 disposed on the printed circuit board; and
A camera module including a lens coupled to the bobbin of the lens driving motor. A portable terminal comprising the camera module of claim 15. Cover cans including side plates;
a bobbin disposed within the cover can;
a coil disposed on the bobbin;
a driving magnet disposed between the coil and the side plate of the cover can;
a sensing magnet disposed on the bobbin;
Including a sensor for detecting the position of the bobbin,
A part of the coil overlaps the sensing magnet and the sensor in a direction perpendicular to the optical axis direction,
At least a portion of the sensing magnet is disposed between the bobbin and the coil,
A circuit board coupled to the cover can and including a terminal portion electrically connected to the sensor,
The coil is wound on the outer surface of the bobbin,
The sensing magnet is fixed to the outer surface of the bobbin,
The cover can includes an opening exposing the terminal portion of the circuit board. delete delete delete

Images