KR102230966B1 - Lens moving apparatus - Google Patents

Abstract

The present embodiment relates to a lens driving apparatus, and more particularly, to a lens driving apparatus capable of shortening a focus alignment time of a lens by feeding back an amount of displacement in an optical axis direction while improving space efficiency of a bobbin.
Specifically, the present embodiment includes a hollow column-shaped housing for supporting a driving magnet; At least one or more lenses are installed inside, a coil disposed inside the driving magnet is provided on an outer circumferential surface, and parallel to the optical axis inside the housing by electromagnetic interaction between the driving magnet and the coil. A bobbin moving in a first direction; It relates to a lens driving apparatus comprising a; displacement detection unit for determining a first displacement value of the bobbin in the first direction.

Description

Lens driving device {LENS MOVING APPARATUS}

The present embodiment relates to a lens driving device, and more particularly, to a lens driving device capable of shortening a focus alignment time of a lens by feeding back an amount of displacement in an optical axis direction while improving space efficiency of a bobbin.

In recent years, the development of IT products such as mobile phones, smart phones, tablet PCs, and notebook computers with built-in micro digital cameras is actively progressing.

In the case of a conventional IT product with a built-in micro digital camera, an image sensor that converts external light into a digital image or a digital image and a lens driving device that aligns the focal length of the lens by adjusting the distance between the lens is built-in.

However, a conventional micro digital camera has a problem that it takes a lot of auto focus time to perform an auto focus function.

Accordingly, it is an object of this embodiment to provide a lens driving apparatus that solves the problems of the prior art.

Specifically, an object of this embodiment is to provide a lens driving device capable of shortening the auto focus time of a lens.

In addition, an object of the present embodiment is to provide a lens driving device that can more accurately and quickly position a lens at the focal length of the lens.

In addition, an object of the present embodiment is to provide a lens driving device in which the autofocus function is improved and space efficiency and durability of the lens driving device are improved at the same time.

According to an embodiment of the present embodiment, the present embodiment includes a hollow column-shaped housing for supporting a driving magnet; A bobbin having a coil disposed inside the driving magnet on an outer circumferential surface, and moving in a first direction parallel to an optical axis in the housing by an electromagnetic interaction between the driving magnet and the coil; It is possible to provide a lens driving device including a displacement sensing unit that determines a first displacement value of the bobbin in the first direction.

In addition, preferably, a printed circuit board installed on one side of the housing; may be characterized in that it further comprises.

In addition, preferably, the displacement detection unit may include a sensing magnet provided in the bobbin, and a position detection sensor provided at a position corresponding to the sensing magnet in the housing.

In addition, preferably, first and second driving magnets are provided on each of the opposite side surfaces of the housing, and a position detection sensor is provided on one side perpendicular to the both side surfaces of the housing or on a surface other than the both side surfaces. It can be characterized by that.

In addition, preferably, first and second driving magnets are provided on each of the opposite side surfaces of the housing, and a third driving magnet and the third driving magnet and the second driving magnet are provided on one side perpendicular to the both side surfaces of the housing or on a surface other than the both side surfaces. A position detection sensor disposed at a predetermined distance from the third driving magnet may be provided, and a fourth driving magnet may be provided on the other side of the housing facing the one side.

In addition, preferably, the driving magnet provided on the one side and the driving magnet provided on the other side may be arranged symmetrically with respect to the center of the housing.

In addition, preferably, the bobbin may further include a receiving groove formed in a predetermined depth inward direction on an outer peripheral surface of the bobbin to accommodate the sensing magnet.

In addition, preferably, at least a part of the receiving groove may be located inside the coil.

In addition, preferably, the receiving groove may be characterized in that a depth between an inner surface on which one surface of the sensing magnet is supported and an outer circumferential surface on which the coil is provided is less than or equal to a thickness of the sensing magnet.

Further, preferably, the receiving groove may be characterized in that it has an opening communicating with the receiving groove on one of a lower surface and an upper surface of the bobbin.

In addition, preferably, the receiving groove includes an inner surface on which one surface of the sensing magnet is supported, and an adhesive groove formed concave inward a predetermined depth more than the inner surface so that the adhesive can be injected. You can do it.

In addition, preferably, the bonding groove may include a first additional groove formed longer than the length of the sensing magnet in the vertical thickness direction of the bobbin.

In addition, preferably, the receiving groove has an opening communicating with the receiving groove at one of a lower surface and an upper surface of the bobbin, and the bonding groove is predetermined from the opening toward the inside of the bobbin. It may be characterized in that it has a second additional groove formed deeply.

In addition, preferably, the bobbin is an additional accommodation formed in a predetermined depth inward direction on the outer circumferential surface of the bobbin at a position symmetrical with the receiving groove based on the center of the bobbin on an outer circumferential surface facing the outer circumferential surface in which the receiving groove is formed It may be characterized in that it further comprises a groove and a weight balance member that is accommodated in the additional receiving groove and has the same weight as the magnetic force sensing member.

In addition, preferably, the inner frame is coupled to the bobbin, and the outer frame may further include an upper elastic member and a lower elastic member coupled to the housing.

According to the above-described problem solving means, the present embodiment can shorten the focusing time of the lens by adjusting the position of the lens in the optical axis direction by feeding back the displacement amount of the lens in the optical axis direction.

In addition, the present embodiment can minimize the gap between the sensing magnet provided in the bobbin of the moving body and the position detection sensor provided in the fixed body housing, and thus, the amount of displacement in the optical axis direction of the lens can be more accurately detected. It can be positioned more accurately and quickly at the focal length of the lens.

In addition, in this embodiment, since the sensing magnet is provided inside the bobbin and the position detection sensor is provided inside the housing, it does not require a separate space for mounting of the displacement detection unit. Can be improved.

1 is a schematic perspective view of a lens driving apparatus according to an embodiment of the present embodiment,
2 is a schematic exploded perspective view of a lens driving apparatus according to an embodiment of the present embodiment,
3 is a schematic perspective view of a lens driving apparatus with a cover member removed from FIG. 1,
Figure 4 is a schematic plan view of Figure 3,
5 is a schematic perspective view of a housing according to an embodiment of the present embodiment,
6 is a schematic perspective view of the housing viewed from a different angle from FIG. 5,
7 is a schematic bottom perspective view of a housing according to an embodiment of the present embodiment,
8 is a schematic exploded perspective view of a housing according to an embodiment of the present embodiment,
9 is a schematic plan view of an upper elastic member according to an embodiment of the present embodiment,
10 is a schematic plan view of a lower elastic member according to an embodiment of the present embodiment,
11 is a schematic perspective view of a bobbin according to an embodiment of the present embodiment,
12 is a schematic bottom perspective view of a bobbin according to an embodiment of the present embodiment,
13 is a schematic exploded perspective view of a bobbin according to an embodiment of the present embodiment,
14 is a partially enlarged perspective view of FIG. 13,
15 is a partially enlarged bottom view of FIG. 13,
16 is a schematic partially enlarged perspective view of a receiving groove according to an embodiment of the present embodiment,
17 is a schematic longitudinal sectional view of a bobbin according to an embodiment of the present embodiment.

Hereinafter, a preferred embodiment of the present embodiment may be described with reference to the accompanying drawings so that a person of ordinary skill in the art can easily implement it. In the accompanying drawings, it may be noted that the same reference number is used as much as possible when indicating the same configuration in other drawings. In addition, in describing the present embodiment, when it is determined that a detailed description of a related known function or a known configuration may unnecessarily obscure the subject matter of the present embodiment, the detailed description thereof may be omitted. In addition, certain features shown in the drawings are enlarged or reduced or simplified for ease of description, and the drawings and their components are not necessarily drawn to scale. However, those skilled in the art will readily understand these details.

For reference, a Cartesian coordinate system (x, y, z) may be used in FIGS. 1 to 17. In the drawing, the x-axis and y-axis refer to a plane perpendicular to the optical axis. For convenience, the optical axis direction (z-axis direction) may be referred to as a first direction, an x-axis direction as a second direction, and a y-axis direction as a third direction. .

1 is a schematic perspective view of a lens driving apparatus 100 according to an embodiment of the present embodiment, FIG. 2 is a schematic exploded perspective view of a lens driving apparatus 100 according to an embodiment of the present embodiment, and FIG. 3 is 1 is a schematic perspective view of the lens driving apparatus 100 with the cover member 300 removed, FIG. 4 is a schematic plan view of FIG. 3, and FIG. 5 is a schematic view of a housing 140 according to an embodiment of the present embodiment. Is a perspective view, Figure 6 is a schematic perspective view of the housing 140 viewed from an angle different from that of Figure 5, Figure 7 is a schematic bottom perspective view of the housing 140 according to an embodiment of the present embodiment, Figure 8 is a view A schematic exploded perspective view of the housing 140 according to an embodiment of the embodiment, FIG. 9 is a schematic plan view of the upper elastic member 150 according to an embodiment of the present embodiment, and FIG. 10 is an embodiment of the present embodiment It is a schematic plan view of the lower elastic member 160 according to.

The lens driving apparatus 100 according to the present embodiment is a device that adjusts the distance between the lens and the image sensor in the camera module so that the image sensor is positioned at the focal length of the lens. That is, the lens driving device 100 is a device that performs an auto-focusing function.

1 to 4, the lens driving device 100 according to the present embodiment includes a cover member 300, an upper elastic member 150, a bobbin 110, and the bobbin 110. The coil 120, the housing 140, the driving magnet 130 and the printed circuit board 170 provided in the housing 140, the lower elastic member 160, the base 210 and the bobbin 110 It may include a displacement detection unit that determines the amount of displacement in the optical axis direction (ie, the first direction).

The cover member 300 may have a box shape as a whole, and may be configured to be coupled to the upper portion of the base 210. The cover member 300 includes an upper elastic member 150, a bobbin 110, a coil 120 provided in the bobbin 110, a housing 140, and the housing in an accommodation space formed together with the base 210 A driving magnet 130 and a printed circuit board 170 provided in 140 may be accommodated.

The cover member 300 may have an opening on an upper surface thereof to allow a lens coupled to the bobbin 110 to be exposed to external light. In addition, a window made of a light-transmitting material may be provided in the opening, thereby preventing foreign matter such as dust or moisture from penetrating into the camera module.

The cover member 300 may include a first groove 310 in the lower portion. At this time, as will be described later, the base 210 is formed at a portion that contacts the first groove 310 when the cover member 300 and the base are coupled (that is, a position corresponding to the first groove 310). 2 grooves 211 may be provided. When the cover member 300 and the base are coupled, a concave portion having a predetermined area may be formed through the combination of the first groove 310 and the second groove 211. An adhesive member having a viscosity may be applied to the concave portion. That is, the adhesive member applied to the concave groove fills a gap between the facing surfaces of the cover member 300 and the base 210 through the concave groove, so that the cover member 300 becomes the base 210 While being coupled to, the space between the cover member 300 and the base 210 may be sealed, and a side surface may be sealed while the cover member and the base are coupled.

In addition, a third groove 320 may be formed on a surface of the cover member 300 corresponding to a terminal surface of the printed circuit board 170 so as not to interfere with a plurality of terminals formed on the terminal surface. The third groove 320 may be formed to be concave on the entire surface facing the terminal surface, and the adhesive member is applied to the inside of the third groove so that the cover member 300, the base 210, and the printed circuit board ( 170) may be sealed, and a side surface may be sealed while the cover member and the base are coupled.

Meanwhile, the first to third grooves 310 to 320 are respectively formed in the base 210 and the cover member 300, but are not limited thereto, and are formed only on the base 210 in a similar shape or , It may be configured to be formed only in the cover member 300.

The base 210 may have a rectangular shape as a whole, and may be combined with the cover member 300 to form an accommodation space for the bobbin 110 and the housing 140.

A stepped portion protruding a predetermined thickness in an outward direction may be provided to surround the lower edge of the base 210. The predetermined thickness of the stepped portion is the same as the side thickness of the cover member 300, and when the cover member 300 is coupled to the base 210, the side surface of the cover member 300 is the upper portion of the stepped portion. Or it may be seated on the side or contacted or placed or coupled to the side. Accordingly, it is possible to guide the cover member 300 coupled to the upper side of the stepped portion, and further, the end of the cover member 300 may be coupled to face contact, and the end of the cover member has a bottom or side surface. Can include. In this case, the end portions of the stepped portion and the cover member 300 may be adhesively fixed and sealed with an adhesive or the like.

In the stepped portion, a second groove portion 211 may be formed at a position corresponding to the first groove portion 310 of the cover member 300. As described above, the second groove portion 211 is coupled to the first groove portion 310 of the cover member 300 to form a groove portion, and a space in which the adhesive member is filled may be formed.

The base 210 may have an opening near the center. The opening may be formed at a position corresponding to the position of the image sensor disposed on the camera module.

In addition, the base 210 may include four guide members 216 protruding from four corners at a predetermined height perpendicular to the upper direction. The guide member may have a polygonal column shape. The guide member 216 may be inserted, fastened, or coupled to the lower guide groove 148 of the housing 140 to be described later. In this way, when the housing 140 is seated or disposed above the base 210 due to the guide member 216 and the lower guide groove 148, the housing 140 on the base 210 is coupled. The position may be guided, and at the same time, the housing 140 may be prevented from being separated from the reference position to be mounted due to vibration or the like during the operation of the lens driving device 100 or due to an operator's mistake during the coupling process.

As shown in FIGS. 4 to 9, the housing 140 may have a hollow column shape as a whole (for example, as shown in the drawing, a hollow square column shape). The housing 140 is configured to support at least two driving magnets 130 and the printed circuit board 170, and the bobbin 110 is movable in a first direction with respect to the housing 140. The bobbin 110 may be accommodated.

The housing 140 may have four flat sides. A side surface of the housing 140 may be formed in an area corresponding to or larger than that of the driving magnet 130.

As shown in Fig. 9, each of the four side surfaces 141 of the housing 140 facing each other has a through hole (141a) or a groove for a magnet to which the driving magnet 130 is seated, placed, or fixed. Can be. The magnet through hole 141a or groove may have a size and shape corresponding to the driving magnet 130, and may also have a shape capable of guiding. A first driving magnet 131 and a second driving magnet 132, that is, a total of two driving magnets 130, may be mounted in each of the through holes 141a for the magnets.

And, of the four side surfaces 141 of the housing 140, a through hole for a sensor through which a position detection sensor 180, which will be described later, is inserted, placed, fixed, or seated on one side perpendicular to the both side surfaces or a surface other than the both side surfaces. (141b) may be provided. It is preferable that the sensor through-hole 141b has a size and shape corresponding to the position detection sensor 180 to be described later. In addition, on the one side, at least one mounting protrusion 149 may be provided to allow the printed circuit board 170 to be mounted or arranged or temporarily fixed or fixed. The mounting protrusion 149 is inserted into the mounting through hole 173 formed in the printed circuit board 170 to be described later, and the mounting through hole 173 and the mounting protrusion 149 are fitted in shape. It may be said that it is desirable to be combined in a method or a force fitting method, but it may only serve as a simple guide function.

Here, among the four side surfaces 141 of the housing 140, the other side facing the one side may be configured as a flat plane, but is not limited thereto.

As a further embodiment of the housing 140, the through holes for the first and second magnets in which the driving magnets 130 are seated, arranged, or fixed on each of the four side surfaces 141 of the housing 140 facing each other. (141a) (141a') may be provided. In addition, among the four side surfaces 141 of the housing 140, one side perpendicular to the two sides or a side other than the two side surfaces has a through hole for a third magnet and a through hole for the third magnet for a sensor formed by a predetermined distance. A through hole 141b may be provided. In addition, a through hole for a fourth magnet may be provided on the other side of the four side surfaces 141 of the housing 140 that faces the one side.

That is, four through-holes for magnets and one through-hole 141b for a sensor may be provided on the four side surfaces 141 of the housing 140.

At this time, the first magnet through hole (141a) and the second magnet through hole (141a') have the same size and the same shape, and (almost) the same throughout the lateral length of the side surface of the housing (140). Have a lateral length. On the other hand, the through-hole for the third magnet and the through-hole for the fourth magnet have the same size and shape, and are larger than the first magnet through-hole 141a and the second magnet through-hole 141a'. The lateral length may be formed to be small. This is to secure a space for the sensor through-hole 141b since the through-hole 141b for the sensor must be formed on one side where the through-hole for the third magnet is formed.

As a matter of course, each of the first through-holes for the first magnet to the through-holes for the fourth magnets 131 to the fourth drive magnets may be seated, arranged, or fixed. At this time, likewise, the first driving magnet 131 and the second driving magnet 132 have the same size and shape, and have substantially the same lateral length over the entire lateral length of the side surface of the housing 140. Have. In addition, the third driving magnet and the fourth driving magnet have the same size and shape, and have a lateral length smaller than that of the first driving magnet 131 and the second driving magnet 132. Can be formed.

Here, preferably, the third magnet through hole and the fourth magnet through hole may be symmetrically disposed in a straight line with respect to the center of the housing 140. That is, the third driving magnet 130 and the fourth driving magnet 130 may be symmetrically disposed on a straight line with respect to the center of the housing 140. If the third driving magnet 130 and the fourth driving magnet 130 are disposed opposite to each other while being deflected on one side regardless of the center of the housing 140, the coil 120 of the bobbin 110 This is because there is a possibility that the bobbin 110 may tilt because the electromagnetic force acts to be deflected on one side. In other words, the third driving magnet 130 and the fourth driving magnet 130 are arranged symmetrically on a straight line with respect to the center of the housing 140, so that the bobbin 110 and the coil 120 ), it is possible to apply an unbiased electromagnetic force to the bobbin 110 so as to easily and accurately move the bobbin 110 in the first direction.

In addition, as shown in FIGS. 3 to 6 and 8, a plurality of first stoppers 143 may protrude from the upper surface of the housing 140. The first stopper 143 is for preventing collision between the cover member 300 and the body of the housing 140, and when an external shock occurs, the upper surface of the housing 140 is directly on the upper inner surface of the cover member 300. It can prevent collision. In addition, the first stopper 143 may also serve to guide the installation position of the upper elastic member 150, for this purpose, as shown in FIG. 9, the first stopper 143 of the upper elastic member 150 A guide groove 155 having a corresponding shape may be formed at a position corresponding to the stopper 143.

In addition, a plurality of upper frame support protrusions 144 to which the outer frame 152 of the upper elastic member 150 is coupled may be formed on the upper side of the housing 140. On the other hand, as will be described later, the outer frame 152 of the upper elastic member 150 corresponding to the upper frame support protrusion 144 may be formed with a first through hole 152a or a groove having a corresponding shape, where It may be fixed with an adhesive or fusion bonding, and the fusion may include heat fusion or ultrasonic fusion.

In addition, as shown in FIG. 7, a plurality of lower frame support protrusions 147 to which the outer frame 162 of the lower elastic member 160 is coupled may be formed to protrude from the lower side of the housing 140. On the other hand, the outer frame 162 of the lower elastic member 160 corresponding to the lower frame support protrusion 147 may be formed with an insertion groove 162a or a hole having a corresponding shape, whereby adhesive or fusion bonding It may be fixed, and the fusion may include heat fusion or ultrasonic fusion.

The driving magnet 130 may be fixed to the magnet through hole 141a with an adhesive, but is not limited thereto, and an adhesive member such as a double-sided tape may be used. Alternatively, as a modified embodiment, instead of the through hole 141a for the magnet, a magnet seating portion having a concave shape may be formed on the inner surface of the housing 140, and the magnet seating portion may correspond to the size and shape of the driving magnet 130 It may have a corresponding size and shape.

The driving magnet 130 may be installed at a position corresponding to the coil 120 provided in the bobbin 110. In addition, the driving magnet 130 may be configured as one body, and in this embodiment, the side facing the coil 120 of the bobbin 110 may be arranged to be N pole and the outer side to be S pole. have. However, it is not limited to this, and it is also possible to configure the opposite. In addition, the driving magnet 130 may be divided into two planes perpendicular to the optical axis.

The driving magnet 130 is configured in a rectangular parallelepiped shape having a certain width, and is seated in the through hole 141a or the groove for the magnet so that the wide surface of the driving magnet 130 is part of the side surface of the housing 140 Can be formed. In this case, the driving magnets 130 facing each other may be installed parallel to each other. In addition, the driving magnet 130 may be disposed to face the coil 120 of the bobbin 110. In this case, surfaces of the driving magnet 130 and the coil 120 of the bobbin 110 may be disposed in a plane so as to be parallel to each other. However, this is not limited thereto, and only one of the driving magnet 130 and the coil 120 of the bobbin 110 may be flat, and the other may be configured as a curved surface, depending on the design. Alternatively, the surfaces facing the coil 120 of the bobbin 110 and the driving magnet 130 may be curved, and at this time, the coil 120 of the bobbin 110 and the driving magnet 130 may face each other. The curvature of the surface can be formed the same.

As described above, a sensor through hole (141b) or a groove is provided on one side of the housing (140), and a position detection sensor (180) is inserted, placed, or seated in the sensor through hole (141b), The position detection sensor 180 is electrically coupled to one surface of the printed circuit board 170 by soldering or soldering. In other words, the printed circuit board 170 may be fixed, supported, or disposed on the outer surface of one side of the through hole 141b for the sensor or the groove provided among the four side surfaces 141 of the housing.

The position detection sensor 180 may be a displacement detection unit that determines a first displacement value of the bobbin 110 in the first direction together with a sensing magnet 190 of the bobbin 110 to be described later. To this end, the position detection sensor 180 and the sensor through hole 141b or groove may be disposed at a position corresponding to the position of the sensing magnet 190.

The position detection sensor 180 may be a sensor that detects a change in magnetic force emitted from the sensing magnet 190 of the bobbin 110. In addition, the position detection sensor 180 may be a Hall sensor. However, this is exemplary, and the present embodiment is not limited to the Hall sensor, and any sensor capable of detecting a change in magnetic force may be used, and any sensor capable of detecting a position other than magnetic force may be used. For example, a method using a photo reflector or the like is also possible.

The printed circuit board 170 is coupled to or disposed on one side of the housing 140 and may include a through hole 173 or a groove for mounting as described above. Accordingly, the installation position of the printed circuit board 170 may be guided by the mounting protrusion 149 provided on one side of the housing 140.

In addition, a plurality of terminals 171 are disposed on the printed circuit board 170 to supply current to the coil 120 and the position detection sensor 180 of the bobbin 110 by receiving external power. The number of terminals 171 formed on the printed circuit board 170 may be increased or decreased according to the type of components requiring control. Meanwhile, according to the present embodiment, the printed circuit board 170 may be formed of an FPCB.

The printed circuit board 170 may include a control unit that readjusts the amount of applied current of the coil 120 based on the first displacement value sensed by the displacement detection unit, that is, the control unit is the printed circuit board. It is mounted on (170). In addition, in another embodiment, the control unit may not be mounted on the printed circuit board 170 but may be mounted on a separate board, which may be a board on which an image sensor of a camera module is mounted, or may be a separate board. .

An actuator driving distance may be additionally calibrated based on a difference in Hall voltage with respect to a change in magnet flux (ie, magnetic flux density) detected by the Hall sensor.

The bobbin 110 may be configured to reciprocate in the first axial direction with respect to the housing 140 fixed in the first axial direction. The auto focusing function may be executed due to the movement of the bobbin 110 in the first axial direction.

The bobbin 110 may be described in more detail below with reference to the drawings.

Meanwhile, the upper elastic member 150 and the lower elastic member 160 may elastically support an upward and/or downward motion of the bobbin 110 in the optical axis direction. The upper elastic member 150 and the lower elastic member 160 may be provided with a leaf spring.

2 to 4, 9 and 10, the upper elastic member 150 and the lower elastic member 160 are inner frames 151, 161 and the housing 140 coupled to the bobbin 110. ) And connecting portions 153 and 163 connecting the outer frames 152 and 162 to the inner frames 151 and 161 and the outer frames 152 and 162.

The connection portions 153 and 163 may be bent at least once to form a pattern having a predetermined shape. The bobbin 110 may be elastically (or elastically) supported by an upward and/or downward motion of the bobbin 110 in the first direction in the optical axis direction through the position change and fine deformation of the connection parts 153 and 163.

According to this embodiment, as shown in FIG. 9, the upper elastic member 150 has a plurality of first through holes 152a in the outer frame 152, and a plurality of second through holes in the inner frame 151 (151a) can be provided.

The first through hole (152a) is coupled to the upper frame support protrusion (144) provided on the upper surface of the housing (140), and the second through hole (151a) or groove is on the upper surface of the bobbin (110) to be described later. It can be combined with the provided upper support protrusion. That is, the outer frame 152 is fixed and coupled to the housing 140 through the first through hole 152a, and the inner frame 151 is fixed to the bobbin 110 through the second through hole 151a or groove. And can be combined.

The connection part 153 may connect the inner frame 151 and the outer frame 152 so that the inner frame 151 is elastically deformable in a first direction with respect to the outer frame 152 in a predetermined range. .

At least one of the inner frame 151 and the outer frame 152 of the upper elastic member 150 is electrically connected to at least one of the coil 120 and the printed circuit board 170 of the bobbin 110 It may be provided with at least one or more.

As shown in FIG. 10, the lower elastic member 160 has a plurality of insertion grooves 162a or holes in the outer frame 162, and a plurality of third through holes 161a in the inner frame 161 or It can have a groove.

The insertion groove (162a) or the hole is coupled to the lower frame support protrusion (147) provided on the lower surface of the housing (140), and the third through hole (161a) or the groove is a lower surface of the bobbin (110) to be described later. It can be combined with the lower support protrusion 114 provided in. That is, the outer frame 162 is fixed and coupled to the housing 140 through an insertion groove 162a or a hole, and the inner frame 161 is attached to the bobbin 110 through a third through hole 161a or a groove. Can be fixed and combined.

The connection part 163 may connect the inner frame 161 and the outer frame 162 so that the inner frame 161 is elastically deformable in a first direction with respect to the outer frame 162 in a predetermined range. .

The lower elastic member 160 may include a first lower elastic member 160a and a second lower elastic member 160b separated from each other as shown in FIG. 10. Through this two-part structure, the first lower elastic member 160a and the second lower elastic member 160b may receive power having different polarities or different power sources. That is, after the inner frame 161 and the outer frame 162 are coupled to the bobbin 110 and the housing 140, respectively, the inner frame corresponding to both ends of the coil 120 disposed on the bobbin 110 By providing a solder part at the position of, conductive connection such as soldering or the like is performed in the solder part to receive power having different polarities or different power sources. In addition, a first lower elastic member is electrically connected to one of both ends of the coil, and the other of both ends of the coil and a second lower elastic member are electrically connected to apply current and/or voltage from the outside. I can receive it.

Meanwhile, the upper elastic member 150 and the lower elastic member 160, the bobbin 110, and the housing 140 may be assembled through thermal fusion and/or bonding using an adhesive or the like. At this time, the fixing operation may be completed by bonding using an adhesive after heat fusion fixing according to the assembly sequence.

As a modified embodiment, the upper elastic member 150 may be configured as a two-part structure, and the lower elastic member 160 may be configured as an integral structure.

At least one of the inner frame 161 and the outer frame 162 of the lower elastic member 160 is electrically connected to at least one of the coil 120 and the printed circuit board 170 of the bobbin 110 At least one or more may be provided.

11 is a schematic perspective view of the bobbin 110 according to an embodiment of the present embodiment, FIG. 12 is a schematic bottom perspective view of the bobbin 110 according to an embodiment of the present embodiment, and FIG. 13 is a schematic perspective view of the bobbin 110 according to an embodiment of the present embodiment. A schematic exploded perspective view of the bobbin 110 according to the embodiment, FIG. 14 is a partially enlarged perspective view of FIG. 13, FIG. 15 is a partially enlarged bottom view of FIG. 13, and FIG. 16 is a housing according to an embodiment of the present embodiment. A schematic partially enlarged perspective view of the groove 117, and FIG. 17 is a schematic longitudinal cross-sectional view of the bobbin 110 according to an embodiment of the present embodiment.

11 to 17, the bobbin 110 may be installed in the inner space of the housing 140 so as to be reciprocally movable in the optical axis direction. A coil 120, which will be described later, is installed on the outer circumferential surface of the bobbin 110 to allow electromagnetic interaction with the driving magnet 130 of the housing 140, so that the electrons of the coil 120 and the driving magnet 130 Due to the miraculous interaction, the bobbin 110 may reciprocate in the first direction. In addition, the bobbin 110 is elastically (or elastically) supported by the upper elastic member 150 and the lower elastic member 160, and moves in a first direction that is an optical axis direction to perform an auto-focusing function. .

Although not shown, the bobbin 110 may include a lens barrel (not shown) in which at least one lens is installed, but the lens barrel is a component of a camera module to be described later, and is an essential component of the lens driving device. It may not be an element. The lens barrel can be coupled to the inside of the bobbin 110 in various ways. For example, a female thread is formed on the inner circumferential surface of the bobbin 110, and a male thread corresponding to the thread is formed on the outer circumferential surface of the lens barrel, and the lens barrel can be coupled to the bobbin 110 by screwing them. However, this is not limited thereto, and the lens barrel may be directly fixed to the inside of the bobbin 110 by a method other than screwing without forming a thread on the inner circumferential surface of the bobbin 110. Alternatively, the one or more lenses may be integrally formed with the bobbin 110 without a lens barrel. The lens coupled to the lens barrel may be configured as one, or two or more lenses may be configured to form an optical system.

In addition, a plurality of upper support protrusions 113 and a plurality of lower support protrusions 114 may protrude on upper and lower surfaces of the bobbin 110.

As shown in FIG. 11, the upper support protrusion may be provided in a cylindrical or prismatic shape, and may couple and fix the inner frame 151 and the bobbin 110 of the upper elastic member 150. According to the present embodiment, a second through hole 151a or a groove may be formed at a position corresponding to the upper support protrusion of the inner frame 151 of the upper elastic member 150. At this time, the upper support protrusion and the second through hole 151a or groove may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of upper support protrusions may be provided. At this time, the distance between each of the upper support protrusions may be appropriately arranged within a range capable of avoiding interference with surrounding parts. That is, the upper support protrusions may be arranged symmetrically with respect to the center of the bobbin 110 at regular intervals, and the intervals thereof are not constant, but symmetrical with respect to a specific imaginary line passing through the center of the bobbin 110 It can also be formed.

The lower support protrusion 114 may be provided in a cylindrical or prismatic shape like the upper support protrusion, as shown in FIG. 12, and includes the inner frame 161 and the bobbin 110 of the lower elastic member 160. Can be combined and fixed. According to this embodiment, a third through hole 161a or a groove may be formed at a position corresponding to the lower support protrusion 114 of the inner frame 161 of the lower elastic member 160. At this time, the lower support protrusion 114 and the third through hole 161a or groove may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of lower support protrusions 114 may be provided as shown in FIG. 12. At this time, the distance between each of the lower support protrusions 114 may be appropriately disposed within a range capable of avoiding interference with surrounding components. That is, each of the lower support protrusions 114 may be arranged symmetrically with respect to the center of the bobbin 110 at regular intervals.

In addition, on the upper and lower surfaces of the bobbin 110, the upper escape groove 112 and the upper escape groove 112 at positions corresponding to the connection part 153 of the upper elastic member 150 and the connection part 163 of the lower elastic member 160 The lower escape groove 118 is formed.

Since the upper escape groove 112 and the lower escape groove 118 are provided, when the bobbin 110 moves in the first direction with respect to the housing 140, the connection portions 153, 163 and the bobbin 110 are By removing the spatial interference, the elastic deformation of the connection portions 153 and 163 may be more easily performed. In addition, the position of the upper escape groove may be disposed at the edge of the housing as in the embodiment, but may be disposed on the side according to the shape and/or position of the connecting portion of the elastic member.

In addition, a seating groove 116 for a coil in which the coil 120 is installed may be provided on the outer circumferential surface of the bobbin 110, but only a seating portion may be provided.

The coil 120 may be provided as an outer circumferential surface of the bobbin 110 or a ring-shaped coil block inserted into and coupled to the coil seating groove 116 or the seating portion, but is not limited thereto. It may be directly wound on the outer circumferential surface of the bobbin 110 or the seating groove 116 or seating portion for the coil.

According to this embodiment, the coil 120 may be formed in an approximately octagonal shape as shown in FIG. 13. This corresponds to the shape of the outer circumferential surface of the bobbin 110, and the bobbin 110 may also be provided in an octagonal shape. In addition, at least four surfaces of the coil 120 may be formed in a straight line, and a corner portion connecting these surfaces may be formed in a round or straight line. In this case, the portion formed in a straight line may be formed to be a surface corresponding to the driving magnet 130. In addition, a surface of the driving magnet 130 corresponding to the coil 120 may have a curvature equal to that of the coil 120. That is, if the coil 120 is straight, the surface of the corresponding driving magnet 130 may be a straight line, and if the coil 120 is curved, the surface of the corresponding driving magnet 130 may be curved. In addition, they may have the same curvature. In addition, even if the coil 120 is curved, the surface of the corresponding driving magnet 130 may be straight or vice versa.

The coil 120 is for moving the bobbin 110 in the direction of the optical axis to perform an autofocus function, and when current is supplied, an electromagnetic force can be formed through electromagnetic interaction with the driving magnet 130. The electromagnetic force can move the bobbin 110.

Meanwhile, the coil 120 may be configured to correspond to the driving magnet 130, and as shown, the driving magnet 130 is configured as a single body, so that the entire surface facing the coil 120 has the same polarity. When provided to have a, the coil 120 may also be configured such that a surface corresponding to the driving magnet 130 has the same polarity. On the other hand, although not shown, if the driving magnet 130 is divided into two surfaces perpendicular to the optical axis and the surface facing the coil 120 is divided into two or more, the coil 120 is also divided. It is also possible to be divided into a number corresponding to the driving magnet 130.

In addition, the bobbin 110 may include a sensing magnet 190 included in a displacement sensing unit together with the position sensing sensor 180 of the housing 140 described above. The sensing magnet 190 may be fixed, disposed, or coupled to the bobbin 110. Accordingly, the sensing magnet 190 may move in the first direction by the same amount of displacement as the bobbin 110 when the bobbin 110 moves in the first direction. In addition, the sensing magnet 190 may be configured as one body, and the upper direction of the bobbin 110 may be an N pole, and the lower direction of the bobbin 110 may be an S pole. However, it is not limited to this, and it is possible to configure the opposite. In addition, the sensing magnet 190 may be divided into two planes perpendicular to the optical axis.

Here, as shown in FIGS. 13 to 17, the bobbin 110 may include a receiving groove 117 for accommodating the sensing magnet 190 on the outer circumferential surface of the bobbin 110.

The receiving groove 117 may be formed from an outer surface of the bobbin 110 to an inner direction of the bobbin 110 to a predetermined depth.

Specifically, the receiving groove 117 may be formed on one side of the bobbin 110 such that at least a portion of the receiving groove 117 is located inside the coil 120. In addition, at least a portion of the receiving groove 117 may be formed to be concave in a predetermined depth toward the inside of the bobbin 110 more than the coil seating groove 116. In this way, by forming the receiving groove 117 in the inner direction of the bobbin 110, the sensing magnet 190 can be accommodated in the bobbin 110, thereby Since there is no need to secure an installation space, space efficiency of the bobbin 110 can be improved.

In particular, the receiving groove 117 may be disposed at a position corresponding to the position of the position detecting sensor 180 of the housing 140 (or a position facing the position detecting sensor 180). For this reason, the distance between the sensing magnet 190 and the position sensing sensor 180 is the thickness of the coil 120 and the separation distance between the coil 120 and the position sensing sensor 180 or the coil and the position sensing sensor here Since the distance between them can be further included and minimized to the distance, the magnetic force detection accuracy of the position detection sensor 180 can be improved.

The receiving groove 117 may have an opening 119 communicating with the receiving groove 117 on one of a lower surface and an upper surface of the bobbin 110. For example, as shown in FIG. 17, the receiving groove 117 is partially opened to form an opening 119 of the lower surface of the bobbin 110, and the opening 119 is the receiving groove 117 Can form the entrance of. The sensing magnet 190 may be inserted, disposed, or fixed through the opening 119, and may be separated through it.

More specifically, as shown in Figs. 15 to 17, the receiving groove 117 is a predetermined inner surface to which one surface of the sensing magnet 190 is supported, and the inner surface so that an adhesive can be injected. It may include an adhesive groove (117b) formed to be concave deeper inward.

The inner surface is a surface located in an inward direction toward the center of the bobbin 110, and when the sensing magnet 190 has a rectangular parallelepiped shape, a surface on which the wide surface of the sensing magnet 190 is in contact or seated to be.

The bonding groove 117b may be a groove formed such that a portion of the inner surface is deeply concave in an inner direction toward the center of the bobbin 110. The adhesive groove 117b may preferably be formed from the opening 119 to an inner surface of the bobbin 110 on which one surface of the sensing magnet 190 is in contact, seated or disposed.

As shown in FIG. 17, the adhesive groove 117b further includes a first additional groove 117c formed longer than the length of the sensing magnet 190 in the vertical thickness direction of the bobbin 110. I can. That is, the first additional groove 117c is an extension of the bonding groove 117b formed to be deeper than the inner surface of the bobbin 110 in which the rear surface of the sensing magnet 190 is in contact, seated or disposed. to be. By providing the first additional groove (117c), when the adhesive is injected into the adhesive groove (117b) through the opening (119), the adhesive is filled from the first additional groove (117c) so that the inside of the adhesive groove (117b) is Since it is filled, it is possible to prevent the adhesive from overflowing in the adhesive groove 117b and flowing to the coil 120 along the gap between the sensing magnet 190 and the receiving groove 117, so that the sensing magnet 190 ) During the coupling process, it is possible to reduce the incidence of defects in the lens driving apparatus 100.

In addition, the bonding groove 117b may further include a second additional groove 117a formed in a predetermined depth from the opening 119 toward the center of the bobbin 110. That is, the second additional groove 117a may be formed deeper in the inner direction toward the center of the bobbin 110 than the inner surface near the opening 119. The second additional groove 117a is in communication with the bonding groove 117b. In other words, the second additional groove 117a is an extension of the bonding groove 117b. In this way, by providing the second additional groove 117a, since the adhesive can be injected into the bonding groove 117b through the second additional groove 117a, the adhesive overflows near the opening 119 and the coil ( Since adhesion to other components of the bobbin 110 such as 120) can be prevented, the occurrence rate of defects in the lens driving device 100 during the coupling process of the sensing magnet 190 can be reduced.

In addition, as a modified embodiment, the second additional groove 117a may be provided in the bobbin 110 alone without an adhesive groove 117b. In this case, an adhesive may be injected into the second additional groove 117a to couple and fix the bobbin 110 and the sensing magnet 190.

Preferably, the bonding groove 117b may include at least one of the first additional groove 117c and the second additional groove 117a. That is, the adhesive groove 117b may have only the first additional groove 117c or only the second additional groove 117a.

In a modified embodiment, the receiving groove has a depth between the inner surface on which one surface (i.e., wide surface) of the sensing magnet is supported and the outer circumferential surface (i.e., the surface of the coil seating groove) on which the coil is provided. It may be less than or equal to the thickness of the dragon magnet. Accordingly, the sensing magnet may be fixed in the receiving groove by an inner pressing force of the coil due to winding of the coil. In this case, there is no need to use an adhesive.

As a further embodiment, although not shown in the drawing, the bobbin 110 is symmetrical with the receiving groove 117 based on the center of the bobbin 110 on an outer circumferential surface facing the outer circumferential surface where the receiving groove 117 is formed. An additional receiving groove 117 formed on the outer circumferential surface of the bobbin 110 and a weight balancing member accommodated in the additional receiving groove 117 may be further included.

That is, the additional receiving groove 117 is a bobbin with a predetermined depth at a position symmetrical with the receiving groove 117 on the basis of the center of the bobbin 110 on the outer circumferential surface facing the outer circumferential surface where the receiving groove 117 is formed. It may be formed in the inner direction of (110). In addition, the weight balance member is fixed and coupled in the additional receiving groove 117, and has the same weight as the magnetic force sensing member.

In this way, by providing the additional receiving groove 117 and the weight balancing member, the horizontal weight imbalance of the bobbin 110 due to the provision of the receiving groove 117 and the sensing magnet 190 is reduced by the mounting of the weight balancing member. You can compensate.

Preferably, the additional receiving groove 117 may include at least one of the bonding groove 117b, the first additional groove 117c, and the second additional groove 117a.

As described above, according to the present embodiment, the lens focus alignment time can be shortened by adjusting the position of the lens in the optical axis direction by feeding back the displacement amount of the lens in the optical axis direction.

In addition, the present embodiment can minimize the gap between the sensing magnet provided in the bobbin of the moving body and the position detection sensor provided in the fixed body housing, and thus, the amount of displacement in the optical axis direction of the lens can be more accurately detected. It can be positioned more accurately at the focal length of the lens.

In addition, in this embodiment, since the sensing magnet is provided inside the bobbin and the position detection sensor is provided inside the housing, a separate space for mounting of the displacement detection unit is not required, so the space efficiency of the camera module (in particular, the bobbin) is improved. Can be improved.

In addition, a lens may be coupled to the lens driving apparatus of the present embodiment, and a camera module may be further provided, including a printed circuit board on which an image sensor and an image sensor are disposed, and the base of the lens driving device and the image sensor are It can be combined with the arranged printed circuit board.

In addition, the camera module may further include a camera module control unit, and a first displacement value calculated based on a current change value detected by the displacement detection unit is compared with a focal length of the lens according to the distance between the subject and the lens. I can. Thereafter, the camera module controller readjusts the amount of current applied to the coil 120 of the bobbin 110 when the first displacement value or the current position of the lens and the focal length of the lens do not correspond to each other, and the bobbin 110 May be moved in the first direction by a second displacement amount. In addition, the displacement detection unit is for the sensing according to the first direction movement of the sensing magnet 190 fixedly coupled to the bobbin 110, the position detection sensor 180 fixedly coupled to the fixed housing 140 The current position or the first displacement amount of the bobbin 110 from a separate driver IC or the camera module control unit based on the current change amount output based on the change amount of the detected magnetic force by sensing the change of the magnetic force emitted from the magnet 190 Can be calculated or judged. In this way, the current position or the first displacement amount of the bobbin 110 calculated or determined by the displacement detection unit is transmitted to the control unit of the printed circuit board 170 so that the control unit re-determines the position of the bobbin 110 for autofocusing, and the coil ( 120) applied current amount can be adjusted.

In the above, a specific embodiment has been illustrated and described to illustrate the technical idea of the present embodiment, but the present embodiment is not limited to the same configuration and operation as the specific embodiment as described above, and various modifications do not depart from the scope of the present embodiment. Can be carried out within. Therefore, such modifications should be regarded as belonging to the scope of this embodiment, and the scope of this embodiment may have to be determined by the claims to be described later.

100: lens driving device
110: bobbin
120: coil
130: driving magnet
140: housing
150: upper elastic member
160: lower elastic member
170: printed circuit board
180: position detection sensor
190: sensing magnet
210: base
300: cover member

Claims (15)

A hollow column-shaped housing for supporting the driving magnet;
A bobbin having a coil disposed inside the driving magnet on an outer circumferential surface, and moving in a first direction parallel to an optical axis in the housing by an electromagnetic interaction between the driving magnet and the coil;
Includes; a displacement detection unit that determines a first displacement value of the bobbin in the first direction,
The lens driving device including a sensing magnet provided in the bobbin and a position sensing sensor provided at a position corresponding to the sensing magnet in the housing. The method of claim 1,
And a printed circuit board installed on one side of the housing. delete The method of claim 1,
First and second driving magnets are provided on each of the opposite side surfaces of the housing,
A lens driving device, wherein a position detection sensor is provided on one side of the housing that is perpendicular to the both side surfaces or on a surface other than the both side surfaces. The method of claim 1,
First and second driving magnets are provided on each of the opposite side surfaces of the housing,
A third driving magnet and a position detection sensor disposed at a predetermined distance apart from the third driving magnet and a third driving magnet are provided on one side or a surface other than the both sides of the housing in the housing,
A lens driving device, characterized in that a fourth driving magnet is provided on the other side of the housing that faces the one side. The method of claim 5,
The driving magnet provided on the one side and the driving magnet provided on the other side are arranged to be symmetrical to each other with respect to the center of the housing. The method of claim 1,
The bobbin further comprises a receiving groove formed in a predetermined depth inward on an outer peripheral surface of the bobbin to receive the sensing magnet. The method of claim 7,
The lens driving apparatus, wherein at least a part of the receiving groove is located inside the coil. The method of claim 8,
The receiving groove is a lens driving device, characterized in that the depth between the inner surface of the sensing magnet is supported and the outer peripheral surface is provided with the coil is less than the thickness of the sensing magnet. The method of claim 7,
And the receiving groove has an opening communicating with the receiving groove at one of a lower surface and an upper surface of the bobbin. The method of claim 7,
The receiving groove,
An inner surface on which one surface of the sensing magnet is supported,
And an adhesive groove formed to be concave inward a predetermined depth more than the inner surface so that the adhesive can be injected. The method of claim 11,
Wherein the bonding groove includes a first additional groove formed longer than the length of the sensing magnet in the vertical thickness direction of the bobbin. The method of claim 11,
The receiving groove has an opening communicating with the receiving groove on one of a lower surface and an upper surface of the bobbin,
Wherein the bonding groove has a second additional groove formed at a predetermined depth from the opening toward the inside of the bobbin. The method of claim 7,
The bobbin,
An additional receiving groove formed in a predetermined depth inward direction on the outer peripheral surface of the bobbin at a position symmetrical with the receiving groove with respect to the center of the bobbin on an outer peripheral surface facing the outer peripheral surface in which the receiving groove is formed,
And a weight balancing member accommodated in the additional receiving groove and having the same weight as the sensing magnet. The method of claim 1,
The inner frame is coupled to the bobbin, and the outer frame is a lens driving apparatus comprising: an upper elastic member and a lower elastic member coupled to the housing.

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