KR102215309B1 - Motor for actuating lens - Google Patents

Abstract

The present invention relates to a lens driving motor, comprising: a coil unit that generates an electromagnetic field when power is supplied; A base layer, a circuit layer stacked on the base layer, a cover layer stacked on the circuit layer, and a copper portion provided on an edge of the base layer and soldered to the coil portion; An FPCB coupled to supply power to the coil unit, wherein the copper unit includes a first surface of the base layer, a second surface facing the first surface, and a second surface connecting the first surface and the second surface. It can be located on three sides.
In the present invention, by extending the cover layer of the FPCB used in the lens driving motor to cover not only the circuit layer but also one end of the copper part of the FPCB, it is possible to prevent the occurrence of cracks in the FPCB even when an impact such as a fall is applied. The reliability of the product is improved.

Description

Lens driving motor{MOTOR FOR ACTUATING LENS}

The present invention relates to a lens driving motor, and more particularly, to a lens driving motor used in a camera module.

As the spread of various portable terminals has become widespread and the wireless Internet service is commercialized, the demands of consumers related to portable terminals are also diversifying. Accordingly, various types of additional devices are installed in the portable terminals.

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

Recently, the demand for small-sized lens-driven motors is increasing for various multimedia fields such as notebook personal computers, camera phones, PDAs, and smart devices, as well as image input devices such as information terminals of surveillance cameras and video tape recorders.

The flexible printed circuit board (FPCB, hereinafter referred to as FPCB) used in the lens driving motor forms a circuit by etching a copper film coated on an insulating polymer film. . These FPCBs can have a double-sided structure and a multi-layered structure through a via hole connection, enabling high-density wiring design. In addition, it has the flexibility to bend and twist well without damaging the wires, making it an indispensable key component in advanced electronic products.

The FPCB used in the lens driving motor is coupled to the OIS coil through a plurality of soldering, and the FPCB and the OIS coil are connected to the circuit.

However, for the reliability of the lens driving motor, when an impact such as a drop is applied, there is a problem that a crack occurs in the FPCB soldered with the OIS coil.

The present invention is to solve the conventional problems as described above, and an object of the present invention is to provide a lens driving motor that prevents the occurrence of cracks in the FPCB even in an impact such as a fall.

In order to achieve the object of the present invention as described above, the lens driving motor according to the first embodiment of the present invention includes a coil unit generating an electromagnetic field when power is supplied; A base layer, a circuit layer stacked on the base layer, a cover layer stacked on the circuit layer, and a copper portion provided on an edge of the base layer and soldered to the coil portion; An FPCB coupled to supply power to the coil unit, wherein the copper unit includes a first surface of the base layer, a second surface facing the first surface, and a second surface connecting the first surface and the second surface. It can be located on three sides.

In the lens driving motor according to the first embodiment of the present invention, a part of the copper part may be located between the base layer and the cover layer.

In the lens driving motor according to the first embodiment of the present invention, the FPCB has a through hole penetrating the FPCB, and the copper part may be located at an outer edge of the base layer or at an edge of the through hole.

In the lens driving motor according to the first embodiment of the present invention, the base layer may be formed of polyimide.

In order to achieve the object of the present invention as described above, the lens driving motor according to the second embodiment of the present invention includes a coil unit generating an electromagnetic field when power is supplied; A base layer, a circuit layer stacked on the base layer, a cover layer stacked on the circuit layer, a copper portion provided on an edge of the base layer and soldered to the coil portion, and coupled to the coil portion A first FPCB and a second FPCB supplying power to the coil part, wherein the copper part comprises a first surface of the base layer of the first FPCB, a second surface of the base layer of the second FPCB facing the first surface, and It may be located on a third surface connecting a side portion connected from the first surface and a side portion connected from the second surface.

In the lens driving motor according to the second embodiment of the present invention, a part of the copper part may be located between the base layer and the cover layer of the first FPCB, or between the base layer and the cover layer of the second FPCB.

In the lens driving motor according to the second embodiment of the present invention, the first FPCB and the second FPCB have through holes, and the copper part may be located at an outer edge of the base layer or at an edge of the through hole. .

In the lens driving motor according to the second embodiment of the present invention, the base layer may be formed of polyimide.

In the present invention, by extending the cover layer of the FPCB used in the lens driving motor to cover not only the circuit layer but also one end of the copper part of the FPCB, it is possible to prevent the occurrence of cracks in the FPCB even when an impact such as a fall is applied. Reliability of the product is improved.

1 is an exploded perspective view of a lens driving motor according to a first embodiment of the present invention.
FIG. 2 is a plan view showing a combined state of an FPCB and an OIS coil of a lens driving motor according to a first embodiment of the present invention.
3 is a cross-sectional view of the FPCB of the lens driving motor according to the first embodiment of the present invention.
4 is a cross-sectional view of an FPCB of a lens driving motor according to a second embodiment of the present invention.

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

<First Example>

Referring to FIG. 1, the lens driving motor according to the first embodiment may largely include a bobbin 100, an AF coil 200, a magnet 300, and a housing 400, and the stator 500 and the first To second elastic members 600 and 610, an OIS spring 620, a base 700, and a cover 800 may be further included. Further, although not shown, the lens driving motor according to the first embodiment may further include a printed circuit board, an IR filter, an image sensor, and the like.

The bobbin 100 is opened up and down and has a cylindrical hollow. The hollow formed in the bobbin 100 is composed of one or two or more lenses to receive a lens unit (not shown) through which light passes, and is screwed.

The AF coil (Auto Focusing Coil) 200 is wound on the outside of the bobbin 100.

The magnet 300 may face the AF coil 200 wound on the outside of the bobbin 100 and a plurality of magnets 300 may be disposed. In addition, when a plurality of magnets 300 are disposed, a distance between the magnets 300 adjacent to each other may be disposed at equal intervals. When a current flows through the AF coil 200, a magnetic field is formed in the AF coil 200, and the magnet 300 raises and lowers the bobbin 100 through an electromagnetic interaction with the AF coil 200.

The housing 400 is formed with a hollow and the upper and lower portions are opened. The housing 400 accommodates the bobbin 100, and the bobbin 100 can move up and down inside the housing 400. The housing 400 includes a plate-shaped rib (not shown in the drawing) extending diagonally from one side to the other side adjacent to the inside of the corner. The space inside the corner of the housing 400 is divided into upper and lower portions by ribs. A magnet receiving portion is provided below the rib, and the magnet 300 is accommodated so that the lower surface of the rib and the upper surface of the magnet 300 abut. Although not shown in the drawing, the upper surface of the rib may be disposed to face each other with the lower surface of the stopper (not shown in the drawing) formed from the outer surface of the bobbin 100 toward the outside.

The elastic member may be divided into a first elastic member 600 and a second elastic member 610.

The first elastic member 600 is formed of a leaf spring and is disposed under the housing 400. The first elastic member 600 has a hole through which light passes through the lens unit. The upper surface around the hole of the first elastic member 600 comes into contact with the lower side of the bobbin 100 to elastically support the bobbin 100 from the housing 400.

The second elastic member 610 is disposed above the housing 400. The second elastic member 610 has a hole through which light passes through the lens unit. The lower surface around the hole of the second elastic member 610 comes into contact with the upper side of the bobbin 100 to elastically support the bobbin 100 from the housing 400.

The first and second elastic members 600 and 610 elastically support the bobbin 100 that is moved up and down by the magnet 300, so that the bobbin 100 moved along the optical axis direction can be restored to its original state. . Meanwhile, in the first embodiment, the arrangement of the first and second elastic members 600 and 610 has been mentioned, but the arrangement is not limited thereto and may be variously arranged according to the user's selection.

The base 700 has a pillar 710 formed at each corner, and a housing 400 is disposed inside the pillar 710 on the base 700. The base 700 supports and supports the housing 400 through an OIS spring (Optical Image Stabilization Spring) 620 to be described later so as to be movable. Since the housing 400 supported by the base 700 has a clearance with the pillar 710, it can be moved horizontally by the clearance distance. However, in the present embodiment, it has been illustrated and described that the pillars 710 are formed at each corner of the base 700, but the present invention is not limited thereto, and if the housing 400 has a gap formed in the base 700 and can move horizontally Can be. A hole through which light passing through the lens unit can pass is formed in the base 700. A stator 500 and a first elastic member 600 are disposed between the base 700 and the housing 400, and the stator 500 may be a coil unit 510 and an FPCB 520.

The coil unit 510 is preferably an OIS coil (Optical Image Stabilization Coil), and is disposed under the first elastic member 600. The coil unit 510 is disposed above the FPCB 520. The coil part 510 has a hole through which light passes through the lens part. A first elastic member 600 is disposed between the coil unit 510 and the housing 400. The coil part 510 faces the lower surface of the magnet 300 accommodated in the housing 400 with a through hole (not shown in the drawing) formed in the first elastic member 600 therebetween. In more detail, the coil unit 510 includes an OIS coil in which the OIS coil faces the lower surface of the magnet 300. That is, the OIS coil is formed at the corner of the coil unit 510 to face the magnet 300. The coil unit 510 performs a function of correcting the user's hand shake by moving the bobbin 100 on which the lens unit is mounted and the housing 400 in a horizontal direction with respect to an image sensor to be described later. That is, when a current flows through the coil unit 510, a magnetic field is formed in the coil unit 510, and the housing 400 and the bobbin 100 accommodated in the housing 400 are formed through electromagnetic interaction with the magnet 300. Move it horizontally.

The FPCB (Flexible Printed Circuit Board) 520 applies power to the coil unit 510. The FPCB 520 is disposed under the coil unit 510. In the FPCB 520, a hole through which light passes through the lens unit is formed. The FPCB 520 transfers the current supplied through the terminal formed on one side to the coil unit 510 or the OIS spring 620 to be described later, and the current transferred to the OIS spring 620 passes through the second elastic member 610. Through the AF coil 200, a magnetic field is formed in the AF coil 200 or the coil unit 510. The FPCB 520 may be a circuit board. The FPCB 520 may include a first portion 520a and a second portion 520b. The FPCB 520 may include a first portion 520a disposed on an upper surface of the base 700 and a second portion 520b extending from the first portion 520a.

An OIS spring (Optical Image Stabilization Spring) 620 is disposed on the side of the housing 400. The OIS spring 620 elastically supports the housing 400 with respect to the base 700. The OIS spring 620 performs a function of returning the bobbin 100 and the housing 400 horizontally moved in the horizontal direction with respect to an image sensor to be described later by the magnetic field of the coil unit 510 and the magnet 300.

Although not shown in the drawing, the printed circuit board may be disposed under the base 700. An image sensor that converts light passing through the lens unit into an electrical signal is mounted near the upper center of the printed circuit board. Components for operation of the image sensor may be disposed on the printed circuit board, or a plurality of terminal units may be provided to supply power and output information of the image sensor. In addition, an infrared cut filter for filtering infrared rays before light passing through the lens unit reaches the image sensor may be installed on the base 700.

The cover 800 may be a shield can disposed outside the housing 400 to cover the above-described components. In addition, the cover 800 may be formed of metal. The cover 800 has a hole formed so that light passes through the lens unit.

Referring to FIG. 2, the FPCB 520 has a terminal portion (not provided with a reference numeral) formed on one side and the other side opposite to one side, and is electrically connected to the printed circuit board to supply power.

In the FPCB 520, a groove (no reference numeral is given) is formed on one side or a side adjacent to the other side, and the OIS spring 620 is fitted into the groove. In addition, the FPCB 520 has a through hole 528 formed between a hole through which light passes and a terminal portion. The through hole 528 is penetrated by the OIS spring 620. In FIG. 2, reference numeral S denotes a point where the FPCB 520 and the coil unit 510 are soldered.

In the first embodiment according to the present invention, the FPCB 520 is disposed under the coil unit 510, and referring to FIG. 3, the FPCB 520 includes a base layer 521, a circuit layer 525, and a cover layer. 526 and a copper portion 527. The FPCB 520 is coupled to the coil unit 510 by soldering.

The base layer 521 may be formed of a plate body, and may be formed of polyimide.

The circuit layer 525 is stacked on the base layer 521. In other words, the circuit layer 525 is formed on the base layer 521 in a predetermined pattern. That is, the base layer 521 is exposed, developed, and etched, and the dry film is removed to form a pattern. And it is formed of copper (Cu) which is a conductive material. Therefore, when power is supplied to the FPCB 520, current may flow on the FPCB 520 along a circuit of a predetermined pattern.

The cover layer 526 is stacked on the circuit layer 525. The cover layer 526 may be formed of a coverlay film. The cover layer 526 is formed with a distance from the base layer 521 by the thickness of the circuit layer 525. In a portion where the circuit layer 525 is not formed between the cover layer 526 and the base layer 521, a spacer 529 is formed to form an empty space. In the first embodiment, the FPCB 520 has a spacing portion 529 to increase the strength of the FPCB 520. However, although it has been described that the spaced portion 529 is present in the first embodiment, the circuit layer 525 stacked on the base layer 521 and the cover layer 526 in both portions of the circuit layer 525 are not formed. It is safe even if the spacer 529 does not exist by being laminated.

In the FPCB 520, a circuit layer 525 and a cover layer 526 may be sequentially stacked on both sides of the base layer 521. In addition, the FPCB 520 is formed with a via hole (not shown in the drawing) to conduct electricity on both sides.

The copper part 527 is located at the outer edge of the FPCB 520 or at the edge of the through hole 528. And the copper part 527 is located at one end of the base layer 521. In more detail, the first surface 522 of the base layer 521, the second surface 523 facing the first surface 522, and the first surface 522 connecting the second surface 523 It is located on the third side 524. The copper portion 527 is not separately installed on each of the first to third surfaces 522, 523, and 524, but is formed to extend on the first to third surfaces 522, 523, and 524. In addition, a part of the copper portion 527, that is, one end portion, is positioned between the base layer 521 and the cover layer 526. In other words, the cover layer 526 covers one end of the copper portion 527. The copper part 527 may be a conductive part.

The material of the copper part 527 may also be formed of copper, the same as the material of the circuit layer 525. At this time, when the circuit layers 525 formed on the first side 522 and the second side 523 are connected to the copper part 527, the copper part 527 is printed on both sides of the FPCB 520 like a via hole. It is also possible to electrically connect the circuit layers 525 to each other.

In FIG. 3, the copper part 527 is shown to be spaced apart through the circuit layer 525 and the spacer 529, but this is only an example, and the copper part 527 may be formed to be connected to the circuit layer 525. . As the copper part 527 of the FPCB 520 is soldered with the coil part 510, the FPCB 520 and the coil part 510 are coupled to each other, and the current flowing through the circuit layer 525 of the FPCB 520 is applied to soldering. By this, it may be transmitted to the coil unit 510. Therefore, when current is supplied to the coil unit 510, the horizontal movement of the housing 400 with respect to the optical axis is possible in accordance with Fleming's left-hand rule through an electromagnetic interaction with the magnet 300.

Since the cover layer 526 covers and supports not only the circuit layer 525 but also one end of the copper part 527, even if an impact such as a drop is applied to the lens driving motor according to the present embodiment, the FPCB 520 Because cracks do not occur, the defect rate is reduced.

<Second Example>

In the second embodiment of the present invention, the same reference numerals are assigned to the same configuration as in the first embodiment, and the overlapping description of the first embodiment will be omitted.

The second embodiment is different from the first embodiment including one FPCB 520 because the FPCB 520 includes the first FPCB 530 and the second FPCB 530'.

Referring to FIG. 4, in the second embodiment according to the present invention, each of the first FPCB 530 and the second FPCB 530' is formed of a plate body, and the first FPCB 530 includes a base layer 531 and a circuit layer. 535) and a cover layer 536, and the second FPCB 530' includes a base layer 531', a circuit layer 535', and a cover layer 536'. In this case, the FPCB 520 may further include a copper part 537. The first FPCB 530 and the second FPCB 530' are symmetrically attached to each other. The first FPCB 530 and the second FPCB 530' are coupled to the coil unit 510 by soldering.

The base layers 531 and 531' may be formed of a plate body, and may be formed of polyimide.

The circuit layers 535 and 535' are stacked on the base layers 531 and 531'. In other words, the circuit layers 535 and 535' are formed on the base layers 531 and 531' in a predetermined pattern. That is, the base layer 521 is exposed, developed, and etched, and the dry film is removed to form a pattern. And it is formed of copper (Cu) which is a conductive material. Therefore, when power is supplied to the FPCB 520, current may flow on the FPCB 520 along a circuit of a predetermined pattern.

The cover layers 536 and 536' are stacked on the circuit layers 535 and 535'. The cover layers 536 and 536' may be formed of a coverlay film. The cover layers 536 and 536' have a distance from the base layers 531 and 531' by the thickness of the circuit layers 535 and 535'. Separating portions 539 and 539' are formed between the cover layers 536 and 536' and the base layers 531 and 531' where the circuit layers 535 and 535' are not formed to form an empty space. In the second embodiment, the FPCB 520 is formed with spaced portions 539 and 539', so that the strength of the FPCB 520 is increased. In the second embodiment, the FPCB 520 has been described as having spaced portions 539 and 539', but the circuit layers 535 and 535' and the circuit layers 535 stacked on the base layers 531 and 531' The cover layers 536 and 536' are stacked on all portions where the, 535') are not formed, so that the spaced portions 539 and 539' do not exist.

In the first FPCB 530 and the second FPCB 530', the base layers 531 and 531' adhere to each other, and each of the first FPCB 530 and the second FPCB 530' with the base layers 531 and 531' Circuit layers 535 and 535' and cover layers 536 and 536' may be sequentially stacked. In other words, in the first FPCB 530, a circuit layer 535 is stacked on one surface of the base layer 531, that is, the first surface 532, and a cover layer 536 is stacked on one surface of the circuit layer 535. , In the second FPCB 530', a circuit layer 535' is stacked on one surface of the base layer 531', that is, a second surface 533', and a cover layer 536' is formed on one surface of the circuit layer 535'. ) Are stacked. In addition, the base layer 531 of the first FPCB 530 and the base layer 531 ′ of the second FPCB 530 ′ adhere to the other surfaces on which the circuit layers 535 and 535 ′ are not stacked.

In addition, a via hole (not shown in the drawing) may be formed to correspond to the first FPCB 530 and the second FPCB 530' in order to conduct electricity between the first FPCB 530 and the second FPCB 530'. .

The copper part 537 is located at the outer edge of the first FPCB 530 and the second FPCB 530' or the edge of the through holes 538 and 538'. Further, the copper part 537 is located at one end of the base layers 531 and 531'. In detail, one surface of the base layer 531 of the first FPCB 530, that is, the first surface 532 and the base layer 531 ′ of the second FPCB 530 ′ facing the first surface 532 It is located on one side, that is, on the second surface 533' and the third surfaces 534 and 534' connecting the side that continues from the first surface 532 and the side that continues from the second surface 533'. The copper part 537 is not positioned on the first to third surfaces 532, 533', 534, and 534', respectively, but extends on the first to third surfaces 532, 533', 534, and 534'. do. In addition, a part of the copper part 537, that is, one end, is between the base layer 531 and the cover layer 536 of the first FPCB 530, or the base layer 531 ′ and the cover layer 536 of the second FPCB 530 ′. ´). In other words, the cover layers 536 and 536' cover both ends of the copper portion 537, respectively.

The material of the copper part 537 may also be formed of copper, which is the same as the material of the circuit layers 535 and 535'. At this time, when the circuit layers 535 and 535' formed on the first surface 532 and the second surface 533' are connected to the copper part 537, the copper part 537 is the first FPCB 530 like a via hole. ) And the circuit layers 535 and 535' printed on the second FPCB 530' may be electrically connected to each other.

In FIG. 4, the copper part 537 is shown to be spaced apart through the circuit layers 535 and 535' and the spacers 539 and 539', but this is only an example, and the copper part 537 is the circuit layers 535 and 535. It can be formed to be connected with ´). As the copper part 537 of the FPCB 520 is soldered with the coil part 510, the FPCB 520 and the coil part 510 are coupled to each other, and the current flowing through the circuit layers 535 and 535' of the FPCB 520 May be transferred to the coil unit 510 by soldering. Therefore, when current is supplied to the coil unit 510, the horizontal movement of the housing 400 with respect to the optical axis is possible in accordance with Fleming's left-hand rule through an electromagnetic interaction with the magnet 300.

Since the cover layers 536 and 536' cover not only the circuit layers 535 and 535' but also both ends of the copper part 537, even if an impact such as a drop is applied to the lens driving motor according to the present embodiment, the FPCB 520 ) Does not generate cracks, reducing the defect rate.

What has been described above is only an embodiment for implementing the lens driving motor according to the present invention, the present invention is not limited to the above embodiment, the present invention without departing from the gist of the present invention claimed in the following claims. Anyone having ordinary knowledge in the technical field to which it belongs will have the technical spirit of the present invention to the extent that it can be implemented by making various changes.

100: bobbin 200: AF coil
300: magnet 400: housing
410: rib 420: stopper receiving groove
430: magnet receiving part 500: stator
510: coil unit 520: FPCB
521: base layer 522: first surface
523: p. 2 524: p. 3
525: circuit layer 526: cover layer
527: copper part 528: through hole
529: separation part 530: first FPCB
530': 2ndFPCB 531, 531': base layer
532: p. 1 533': p. 2
534, 534´: page 3 535, 535´: circuit layer
536, 536': cover layer 537: copper part
538, 538´: through hole 539, 539 ´: separation
600: first elastic member 610: second elastic member
620: OIS spring 700: base
710: pillar 800: cover
S: Soldering

Claims (15)

housing;
A bobbin disposed in the housing;
A base disposed under the housing;
A first coil disposed on an outer peripheral surface of the bobbin;
A magnet disposed in the housing and facing the first coil;
A circuit board disposed on the upper surface of the base;
A second coil disposed on an upper surface of the circuit board and facing the magnet; And
A solder electrically connecting the second coil and the circuit board,
The circuit board includes a first portion disposed on an upper surface of the base and a second portion extending from the first portion, and a conductive portion disposed on the first portion and formed of a conductive material to be coupled to the solder. Including,
The circuit board includes a hole disposed at a position corresponding to an outer edge of the upper surface of the base,
The lens driving motor includes a first conductive part disposed on an outer edge of the circuit board and a second conductive part disposed on an inner edge of the hole of the circuit board. The method of claim 1,
The first portion of the circuit board includes a base layer, a circuit layer disposed on the base layer, and a cover layer disposed on the circuit layer, and an edge of the base layer includes a first surface and the first surface And a second surface opposite to and a third surface connected to the first surface and the second surface,
The lens driving motor covers the first surface, the second surface, and the third surface of the base layer. The method of claim 2,
A lens driving motor in which a portion of the conducting part is disposed between the cover layer and the base layer. The method of claim 2,
A lens driving motor that partially overlaps the base layer and the cover layer in the optical axis direction. The method of claim 1,
The lens driving motor includes four first conductive parts spaced apart from each other, and the second conductive part includes four second conductive parts spaced apart from each other. The method of claim 1,
The circuit board includes a groove formed at the outer edge of the circuit board,
The lens driving motor in which the groove of the circuit board is disposed at a position corresponding to the first electric current part. The method of claim 2,
The circuit layer includes a first circuit layer disposed on an upper surface of the base layer and a second circuit layer disposed on a lower surface of the base layer,
The cover layer includes a first cover layer disposed on an upper surface of the first circuit layer and a second cover layer disposed on a lower surface of the second circuit layer. The method of claim 7,
The conducting part comprises a first part disposed on the first surface of the base layer, a second part disposed on the second surface of the base layer, and the second part and the first part of the conducting part. It includes a third part to connect,
At least a portion of the first portion of the conducting part is disposed between the first cover layer and the base layer,
At least a portion of the second portion of the current-carrying part is disposed between the second cover layer and the base layer. The method of claim 8,
The first portion of the conducting portion includes a surface in contact with the first cover layer, and the second portion of the conducting portion includes a surface in contact with the second cover layer. The method of claim 2,
The lens driving motor in contact with the energizing portion of the cover layer. The method of claim 2,
A lens driving motor having a space formed between the cover layer, the base layer, the energizing part, and the circuit layer. The method of claim 2,
The lens driving motor is formed by separating the base layer into two base layers. The method of claim 2,
The lens driving motor is formed of copper and the base layer includes polyimide. Printed circuit board;
An image sensor disposed on the printed circuit board;
The lens driving motor of claim 1 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 14.

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