KR102478151B1 - Motor for actuating lens - Google Patents

Abstract

The embodiment includes a base, a lens unit having one or more lenses, and a bobbin for fixing the lens unit, and an actuator unit provided on the upper side of the base to move the lens unit, accommodating the lens unit and the actuator, , Including a cover can mounted on the base in close contact with the side surface of the base, wherein the lower end of the inner surface of the cover can includes a recess portion formed to be spaced apart from the side surface of the base.

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. .

A lens driving motor provided in a conventional camera module has a structure in which a lens unit is supported in the air by a plurality of springs, and reliability due to deformation of the spring due to the weight of the lens unit or an impact caused by an external force may deteriorate.

In addition, in the case of a lens driving motor of a conventional optical image stabilization (OIS) type, a spring for driving the OIS should be additionally provided.

(Patent Document 1) KR 10-2011-0080590 A

An embodiment is to provide a lens driving motor with improved reliability in consideration of miniaturization and simplification.

The embodiment is a bobbin for fixing the lens unit; a housing having an opening through which the lens unit is exposed on an upper side thereof and having an open lower side; a base closing the lower surface of the housing and supporting the bobbin; an actuator unit disposed inside the housing to move the bobbin; and at least two spherical support balls provided between the bobbin and the housing.

On the other hand, the embodiment is a bobbin for fixing the lens unit; a housing having an opening through which the lens unit is exposed on an upper side thereof and having an open lower side; a base closing the lower surface of the housing and supporting the bobbin; an actuator part including a magnet part provided on an outer surface of the bobbin and a coil part including two or more coils provided on an inner surface of the housing opposite to the magnet part and receiving power individually; At least two spherical support balls provided in the bobbin and the housing; It is possible to provide a camera module including; and a substrate for applying power to the actuator unit.

In addition, at least two or more fixing protrusions protruding upward are formed on the outer side of the base, and the bobbin may be formed with a fixing groove that is longer than the length of the fixing protrusion to which the fixing protrusion is fixed.

In addition, the fixing protrusion may be formed at each corner of the base, and the fixing groove may be formed at each corner of the bobbin.

In addition, the support ball may be disposed between the fixing protrusion and the fixing groove.

In addition, the outer surface of the fixing groove may be formed to be curved with a curvature corresponding to the support ball.

In addition, the support ball may be formed in a size that does not contact any one of two adjacent surfaces of the housing and an outer surface of the fixing groove.

In addition, the actuator unit may include a magnet unit provided on an outer surface of the bobbin; and a coil part provided on an inner surface of the housing opposite to the magnet part and including two or more coils to which power is individually applied, or provided on an outer surface of the bobbin and individually supplied with power. a coil unit including two or more receiving coils; and a magnet part provided on an inner surface of the housing to face the magnet part.

In addition, the support ball may be disposed between the actuator units.

In addition, a cover can accommodating the housing may be further included.

According to an embodiment of the present invention, a lens driving motor or a camera module with improved miniaturization, simplification, and reliability of the entire lens driving motor including individual control of coils and support balls can be implemented.

1 is a perspective view of a lens driving motor according to an embodiment of the present invention;
2 is a view in which the housing is removed from FIG. 1;
3 is an exploded side view of a lens driving motor according to an embodiment of the present invention.
4 is a view showing a lower side of a lens driving motor according to an embodiment of the present invention from which a base is removed.

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.

Hereinafter, the lens driving motor of the embodiment will be described in detail with reference to the drawings.

1 is a perspective view of a lens driving motor according to an embodiment of the present invention, FIG. 2 is a view in which a housing is removed from FIG. 1, FIG. 3 is an exploded side view of a lens driving motor according to an embodiment of the present invention, and FIG. It is a view showing the lower side of the lens driving motor according to the embodiment of the present invention from which the base is removed.

1 to 4 , the lens driving motor according to the embodiment may largely include a bobbin 200, a housing 100, an actuator unit 300, a base 400, and a support ball 500.

The bobbin 200 is coupled to a lens unit (not shown) to fix the lens unit, and the coupling method between the lens unit and the bobbin 200 is to attach a screw thread (not shown) to the inner circumferential surface of the bobbin 200 and the outer circumferential surface of the lens unit. Although a threaded coupling method for forming each may be used, it may also be coupled as a threadless method using an adhesive. Of course, even in the screw thread coupling method, after screw thread coupling, an adhesive may be used to promote more robust mounting between the two components.

In addition, a mounting groove 220 may be formed on an outer circumferential surface of the bobbin 200 in a shape corresponding to the magnet part 320 so that the magnet part 320 to be described later may be mounted. These mounting grooves 220 may be formed continuously along the outer surface of the bobbin 200 or may be formed spaced apart at predetermined intervals.

In addition, a fixing groove 210 formed between the mounting grooves 220 on an outer circumferential surface of the bobbin 200 and mounting a fixing protrusion 410 of the base 400 to be described later may be additionally formed. The fixing grooves 210 may be formed at each corner of the bobbin 200, and may be longer than the length of the fixing protrusion 410 from the lower side to the upper side of the bobbin 200. In addition, a support ball 500 to be described later may be formed to be disposed between the fixing groove 210 and the fixing protrusion 410 . In addition, the outer surface of the fixing groove 210 may be formed to be curved with a curvature corresponding to that of the support ball 500 . In addition, since the fixing groove 210 and the fixing protrusion 410 are in an assembly shape for coupling the bobbin 200 and the base 400, a separate fixing groove 210 and/or the fixing protrusion 410 are not required. may be In addition, a fixing groove supporting the ball may be formed, which may be formed to a depth greater than a movement distance for driving or a driving stroke, and may be generally about 0.3 mm.

In addition, the concave length of the fixing groove 210 in the direction of the optical axis may be smaller than the diameter of the support ball 500 to be described later. That is, the spherical support ball 500 disposed in the fixing groove 210 may be disposed so that a certain portion is exposed to the outside of the bobbin 200 .

As shown in FIGS. 3 and 4 , the mounting groove 220 may include four mounting grooves and the fixing groove 210 may include four fixing grooves. One of the four mounting grooves and the four fixing grooves may be referred to as a 'first groove', the other referred to as a 'second groove', and the other referred to as a 'third groove'.

The housing 100 may be formed in a shape in which an opening through which the lens unit (not shown) is exposed is formed on an upper side surface and a lower side is open. Specifically, the housing 100 accommodates the bobbin 200, the actuator unit 300, and the support ball 500 and is combined with a base 400 to be described later to form the appearance of a lens driving motor. It may be formed in a shape corresponding to that of the cover can (not shown). Alternatively, the housing 100 may be integrally formed with the cover can to form the exterior of the lens driving motor.

In the embodiment, the housing 100 is formed in a hexahedron shape, but is not limited to this shape, and may be formed in various angular column shapes. In addition, the housing 100 is formed of an insulating material and may be formed as an injection molding product in consideration of productivity.

In addition, a stopper (not shown) protruding at a predetermined interval from the upper surface of the housing 100 or bobbin 200 to absorb shock by contacting the upper surface of the cover can or housing 100 in case of external impact At least two or more may be formed. This stopper may be integrally formed with the housing 100 or the bobbin 200.

As described above, the housing 100 may be implemented as a cover can or accommodated inside the cover can.

The cover can (not shown) may form the exterior of the camera module by accommodating the housing 100 and being mounted on the base 400 . Alternatively, the housing functioning as the cover can may be mounted on the base 400 in close contact with a side surface of the base 400 to be described later, and protect internal components from external impact and at the same time external contamination. It may have a material penetration prevention function.

In addition, since the cover can can also perform a function of protecting components of the camera module from external radio wave interference generated by a mobile phone, the cover can can be formed of a metal material.

In addition, although not shown, at least one extending fastening piece is further formed on each surface of the lower end of the cover can, and a fastening groove into which the fastening piece is inserted is formed extending outward in the base 400 to make the camera module more robust. A sealing function and a fastening function can be implemented.

The actuator part 300 is disposed inside the housing 100 to move the bobbin 200, and may largely include a magnet part 320 and a coil part 310.

The magnet part 320 is mounted and fixed to the outer surface of the bobbin 200 or the mounting groove 220 so that it can be disposed at a position corresponding to the inner surface of the coil part 310 to be described later, or fixed with an adhesive. It can be. In addition, although the magnet part 320 is shown to be disposed on the outer surface of the bobbin 200, it is mounted at equal intervals on the four corners of the bobbin 200 to efficiently use the internal volume of the lens driving motor. can also help

Alternatively, the magnet part 320 is disposed inside the housing 100 instead of the bobbin 200, and a coil part 310 to be described later is disposed on the outer surface of the bobbin 200 and the magnet part 320. They may be mounted oppositely.

Although the shape of each magnet constituting the magnet part 320 is shown as a rectangular parallelepiped, it may be a triangular prism shape, a square prism shape, a trapezoidal prism shape, etc., and may include some curves in each column shape. may be In addition, the magnet may be processed to have a partially curved edge during processing.

The coil part 310 may be wound on the inner surface of the housing 100 to face the magnet part 320 , or a pre-wound coil part 310 may be mounted on the housing 100 . Here, in the coil unit 310 of the embodiment, four individual coils may be disposed on the inner surface of the housing 100 at intervals of 90°, and these individual coils may receive external power individually.

That is, in the coil unit 310 of the embodiment, at least two or more individually driven coils are disposed, and due to the individual driving of the coil unit 310 and the support ball 500 to be described later, not only the A.F (Auto Focusing) function In addition, it is possible to implement an OIS (Optical Image Stabilization) function. In short, by implementing a lens driving motor without a separate OIS component, it is possible to achieve effects such as miniaturization and reduction in product assembly process.

The base 400 supports the bobbin 200 and the actuator part 300 by closing part and/or all of the lower surface of the housing 100, and a through hole corresponding to the lens part is formed in the center. do.

The base 400 may perform a sensor holder function to protect an image sensor (not shown) to be described later.

In addition, one or more fixing protrusions 410 may be formed on the outside of the base 400 and protrude upward to face or combine with the fixing groove 210 of the housing 100, and these fixing protrusions 410 may be formed at each corner of the base 400.

In addition, although not shown in the base 400, a fastening groove into which a fastening piece of the cover can is inserted may be formed to extend on an outer surface of the base 400. These fastening grooves are formed locally on the outer surface of the base 400 in a shape corresponding to the length of the fastening piece, or the outer surface of the base 400 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, the embodiment includes at least two or more spherical support balls 500 provided between the bobbin 200 and the housing 100 or between the bobbin 200 and the base 400. The support ball 500 may be disposed between the actuator unit 300 and may also be disposed between the fixing protrusion 410 and the fixing groove 210 . In addition, the support ball 500 may be formed in a size that does not come into contact with either of two adjacent surfaces of the housing 100 and an outer surface of the fixing groove 210 .

That is, the diameter of the support ball 500 may be smaller than the length from the outer surface of the fixing groove 210 to the edge of the housing 100 . When the support ball 500 is spaced apart from the fixing groove 210 or the housing 100 by a predetermined distance, the bobbin 200 is connected to the individually powered coil within the housing 100. A predetermined angle can be controlled in the z-axis direction or the x- and y-axis directions, which is the optical axis direction. That is, the support ball 500 may guide movement of the bobbin 200 in the optical axis direction. The support ball 500 may guide movement of the bobbin 200 in the x-axis direction. Also, the support ball 500 may guide movement of the bobbin 200 in the y-axis direction.

For example, referring to FIG. 4 , in the actuator unit 300 of the embodiment, a total of four pairs of actuators, one pair of coil and magnet, are disposed on each side, and each coil 310a, 310b, 310c, and 310d of the actuator are individually powered.

Here, when the same current is individually applied to each of the coils 310a, 310b, 310c, and 310d, the bobbin 200 moves up and down in the optical axis direction. In addition, when different currents are individually applied to each of the coils 310a, 310b, 310c, and 310d, or when current is applied to only one coil (for example, 310a, 310b, and 310c, or 310a, 310b, or 310a), the above The bobbin 200 may be tilted by the distance between the support ball 500 and the housing 100 and/or the base and/or the bobbin.

Meanwhile, the embodiment may further include a hall sensor unit (not shown) to control each of the coils 310a, 310b, 310c, and 310d for autofocusing and/or anti-shake of the lens driving motor. The hall sensor unit may be provided to sense the phase of the mover by sensing the movement of the magnet unit 320 and precisely control the lens driving motor.

The hall sensor unit may be provided in the stator.

Specifically, the hall sensor unit may be mounted at the center of each of the coils 310a, 310b, 310c, and 310d, and at least two or more of them may be installed at the center of two adjacent coils in order to detect displacement in the x-axis and/or y-axis. Each may be provided. That is, the hall sensor unit having this arrangement structure does not require a separate sensing magnet and senses the magnet unit 320 for driving. In order to effectively implement this sensing, the magnet part 320 may be disposed on the bobbin so as to be positively magnetized.

In addition, when a separate sensing magnet is further disposed on the bobbin, a hall sensor unit may be disposed on the stator at a position corresponding to the sensing magnet. That is, when a separate sensing magnet is provided, the hall sensor unit may be disposed on the housing or base to face the sensing magnet.

By this support ball 500, the embodiment does not need to have a separate OIS coil unit 310, and the spring structure between the bobbin 200 and the housing 100 is not required. This has the advantages of miniaturization by simplifying the number of parts, strengthening durability, shortening the assembly process, and reducing product cost.

In addition, silicon or a damper may be applied to the surface of the support ball 500, and in this case, external shock or noise generation may be reduced.

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, although not shown, a substrate and an image sensor may be further included in addition to the components of the lens driving motor described above.

The lens unit (not shown) includes one or more lenses (not shown), and may be a lens barrel, but is not limited thereto, and may include any holder structure capable of supporting the lens. In the embodiment, a case in which the lens unit is a lens barrel will be described as an example.

An IR filter (not shown) may be disposed in the through hole of the base.

In this case, the IR filter may be mounted in a through hole formed in the center of the base 400, and an infrared ray filter or a blue filter may be provided. In addition, the IR 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 disposed below the base 400 may be further included.

On the other hand, in the case where the IR filter is installed outside the lens, it is of course possible to block infrared rays by coating the lens surface without configuring the IR filter separately.

The board (not shown) may be a printed circuit board (Printed Circuit Board), and an image sensor (not shown) may be mounted on a central portion of an upper side surface. In addition, the board is individually electrically connected to a terminal unit or directly to each coil of the coil unit 310 in order to apply power for driving the lens driving motor according to the embodiment.

The image sensor (not shown) may be mounted on a central portion of an 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. Such an image sensor converts an optical signal of an object incident through a lens into an electrical signal.

On the other hand, the adhesive described in the embodiments may be implemented as a thermosetting epoxy or UV epoxy, and is 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.

In short, according to the embodiment, since a separate OIS spring and/or coil unit 310 including the individual control of the coil and the support ball 500 is not required, the overall lens driving motor can be miniaturized, simplified, and reliable. An improved lens driving motor or camera module can be implemented.

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: housing 200: bobbin
210: fixing groove 220: mounting groove
300: actuator unit 310: coil unit
320: magnet part 400: base
410: fixed protrusion 500: support ball

Claims (25)

Base;
a bobbin including a first side surface and a second side surface forming a first corner and disposed on the base;
a first magnet disposed on the first side of the bobbin;
a second magnet disposed on the second side of the bobbin;
a first coil facing the first magnet;
a second coil facing the second magnet; and
In the optical axis direction, a ball disposed between the bobbin and the base,
the bobbin is disposed to move in the optical axis direction, in a first direction perpendicular to the optical axis direction, and in a second direction perpendicular to the optical axis direction and the first direction;
The bobbin includes a first groove formed by recessing the lower surface of the bobbin in an area of the first corner of the bobbin, a second groove formed on the first side surface of the bobbin and in which the first magnet is disposed, and A third groove formed on the second side of the bobbin and in which the second magnet is disposed,
The first groove of the bobbin is formed between the second groove and the third groove on the outer surface of the bobbin,
The bobbin includes a fourth groove formed in a direction opposite to the first groove and open in the first direction and the second direction;
The balls include a first ball disposed in the first groove of the bobbin and a second ball disposed in the fourth groove,
The second ball guides the movement of the bobbin in the first direction and the second direction. According to claim 1,
The first coil is disposed at a position corresponding to the first magnet in the first direction,
The second coil is disposed at a position corresponding to the second magnet in the second direction. According to claim 1,
The first groove of the bobbin is recessed from the outer surface of the bobbin and the lower surface of the bobbin. According to claim 1,
The second groove and the third groove are spaced apart from each other,
The lens driving motor to which power is individually applied to the first coil and the second coil. According to claim 1,
The first coil and the second coil are disposed adjacent to each other in a direction perpendicular to each other. According to claim 1,
A third coil disposed on the opposite side of the first coil and a fourth coil disposed on the opposite side of the second coil,
The lens driving motor to which power is individually applied to the first to fourth coils. According to claim 1,
A lens driving motor including a hall sensor for controlling the first coil and the second coil for optical image stabilization (OIS). According to claim 7,
The hall sensor is disposed in the first coil and the second coil. According to claim 1,
The first ball overlaps the first magnet in the second direction and overlaps the second magnet in the first direction. According to claim 1,
The ball includes a third ball and a fourth ball disposed on opposite sides of the optical axis,
The first ball, the third ball, and the fourth ball guide the movement of the bobbin in the first direction and the second direction, respectively. According to claim 1,
The second ball is in contact with a part of the bobbin and a part of the base,
The part of the bobbin and the part of the base overlap in the optical axis direction. According to claim 11,
A distance in the optical axis direction between the part of the bobbin and the part of the base is equal to the diameter of the second ball. According to claim 1,
The ball is a lens driving motor overlapping the bobbin and the base in the optical axis direction. According to claim 1,
The ball does not overlap with the base in a direction perpendicular to the optical axis direction. According to claim 1,
A cover can including a top plate and a side plate extending from the top plate and covering the bobbin,
The ball is a lens driving motor spaced apart from the side plate of the cover can. According to claim 1,
A lens driving motor in which silicon or a damper is applied to the surface of the ball. According to claim 10,
Each of the first to fourth balls guides movement of the bobbin in the optical axis direction. delete delete delete delete delete delete printed circuit board;
an image sensor disposed on the printed circuit board;
a lens driving motor according to any one of claims 1 to 17 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 24.

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