KR102220797B1 - Voice coil motor - Google Patents

Abstract

The voice coil motor includes a base having an opening; A mover disposed on the base and including a bobbin having a coil block wound on an outer peripheral surface thereof; A stator including magnets facing the coil block and a cover can enclosing the mover and the magnets and extending at least a portion thereof to face the inner surface of the bobbin; And an elastic member elastically supporting the mover.

Description

Voice coil motor {VOICE COIL MOTOR}

The present invention relates to a voice coil motor.

In recent years, mobile phones and smart phones are equipped with ultra-small digital cameras capable of capturing images or recording videos.

In the case of a conventional micro digital camera mounted on a mobile phone or the like, it is difficult to obtain a high-quality image because the distance between the image sensor generating a digital image and a lens disposed in front of the image sensor cannot be adjusted.

Recently, a lens driving device such as a voice coil motor capable of adjusting the distance between the image sensor and the lens has been developed, so that a higher quality image can be obtained from a digital camera.

Conventional voice coil motors require a coil block wound on a bobbin as a mover, a magnet facing the coil block, and a yoke to prevent leakage of a magnetic field generated from the magnet, and a part of the yoke is interposed between the magnet and the coil block. .

However, the conventional voice coil motor has a problem that the size of the voice coil motor increases and the number of parts and the number of assembly processes increases due to a yoke for preventing leakage of a magnetic field generated from the magnet.

The present invention provides a voice coil motor suitable for reducing the size, the number of parts and the number of assembly processes by preventing the leakage of the magnetic field generated from the magnet without a yoke that serves to prevent leakage of the magnetic field generated from the magnet.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. will be.

In one embodiment, the voice coil motor includes a base having an opening; A mover disposed on the base and including a bobbin having a coil block wound on an outer peripheral surface thereof; A stator including magnets facing the coil block and a cover can enclosing the mover and the magnets and extending at least a portion thereof to face the inner surface of the bobbin; And an elastic member elastically supporting the mover.

According to the voice coil motor according to the present invention, the operation efficiency of the mover is improved by preventing leakage of the magnetic field generated from the magnet or the coil block, and the number of parts and assembly time is reduced by the cover can performing the yoke function together. It also has the effect of reducing the size.

1 is an exploded perspective view of a voice coil motor according to a first embodiment of the present invention.
FIG. 2 is a partially cut-away cross-sectional perspective view of FIG. 1.
3 is an exploded perspective view showing a voice coil motor according to a second embodiment of the present invention.
4 is an enlarged view of part'A' of FIG. 3.
5 is an exploded perspective view showing a voice coil motor according to a third embodiment of the present invention.
6 is an enlarged view of a portion'B' of FIG. 5.
7 is an exploded perspective view showing a voice coil motor according to a fourth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this process, the size or shape of the components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms specifically defined in consideration of the configuration and operation of the present invention may vary according to the intention or custom of users or operators. Definitions of these terms should be interpreted as meanings and concepts consistent with the technical idea of the present invention based on the contents throughout the present specification.

Example 1

1 is an exploded perspective view of a voice coil motor according to a first embodiment of the present invention. FIG. 2 is a partially cut-away cross-sectional perspective view of FIG. 1.

1 and 2, the voice coil motor 600 includes a base 100, a mover 200, a stator 300, and an elastic member 400.

The base 100 is formed in the shape of a rectangular parallelepiped plate, and an opening 110 suitable for passing light to an image sensor disposed on the rear surface of the base 100 is formed in the base 100.

A support column 120 integrally formed with the base 100 is formed on the upper surface of the base 100 to support a magnet to be described later and fix the elastic member. Alternatively, a frame-shaped lower spacer may be disposed on the upper surface of the base 100 to fix the magnet by pressing the support and the elastic member.

The mover 200 includes a bobbin 210 and a coil block 220 in which a lens is mounted.

The bobbin 210 is formed in a cylindrical shape for mounting a lens on an inner circumferential surface of the bobbin 210, and a stepped 215 is formed on the inner circumferential surface of the bobbin 210 on which a part of a cover can to be described later is disposed. A female threaded part 212 for mounting a lens is formed at the lower end of the inner circumferential surface of the bobbin 210 based on the stepped jaws 215 formed on the inner circumferential surface of the bobbin 210.

The upper and lower surfaces of the bobbin 210 are each formed with a coupling protrusion or a coupling boss for coupling with an elastic member to be described later.

In addition, a coil block support part 230 for supporting a coil block 220 to be described later is formed at the lower end of the outer circumferential surface of the bobbin 210.

The coil block 220 is disposed on the outer surface of the bobbin 210 and is supported by the coil block support part 230. The coil block 220 is formed in a cylindrical shape suitable for being disposed on the outer surface of the bobbin 210, and the coil block 220 is formed by winding a long wire coated with an insulating resin such as enamel resin.

The coil block 220 may be directly wound on the outer surface of the bobbin 210 or the coil block 220 wound on the outer surface of the bobbin 210 may be adhered to the outer surface of the bobbin 210 through an adhesive.

A coil block support part 230 for supporting the coil block 220 is formed at the lower end of the outer circumferential surface of the bobbin 210.

The stator 300 includes a magnet 310 and a cover can 320.

The magnet 310 is disposed around the coil block 220, and four magnets 310 are disposed around the coil block 220, for example. In one embodiment of the present invention, each magnet 310 is formed in a block shape. Alternatively, the magnet 310 may be a flat magnet or a curved magnet.

The mover 200 is separated from the base 100 by an attractive force or repulsive force generated by a magnetic field generated from the magnet 310 and a magnetic field generated from the coil block 220.

The cover can 320 prevents leakage of the magnetic field generated from the magnet 310 and the coil block 220, protects the mover 200 and the magnet 310, and prevents harmful electromagnetic waves from the voice coil motor 600. Prevents it from being released to the outside.

In one embodiment of the present invention, the cover can 320 is formed by processing a metal plate.

The cover can 320 includes a side plate 312, an upper plate 314, and a magnetic flux leakage preventing part 316.

The side plate 312 is formed in, for example, a square cylindrical shape with an open top and a bottom surface. The upper plate 314 is formed on the upper surface of the side plate 312, and an opening 315 is formed in the upper plate 314 to expose a lens mounted on the bobbin 210.

In one embodiment of the present invention, the side plate 312 formed by processing the metal plate may be electrically connected to the ground terminal formed on the base 100, and thus harmful electromagnetic waves generated from the voice coil motor 600 It is changed into shape and extinguished through the ground terminal.

The magnetic flux leakage preventing unit 316 extends from the inner surface formed by the opening 315 of the upper plate 314 to face the inner surface of the bobbin 210, and in one embodiment of the present invention, the magnetic flux leakage preventing unit 316 ) Extends in a cylindrical shape along the inner surface of the bobbin 210 from the upper plate 314.

The end of the magnetic flux leakage preventing portion 316 extending in a cylindrical shape is disposed above the stepped jaw 215 formed on the inner surface of the bobbin 210.

The magnetic flux leakage preventing unit 316 improves driving efficiency of the mover 200 by blocking leakage of the magnetic field generated from the magnet 310 and/or the coil block 220. In addition, the magnetic flux leakage preventing unit 316 also serves to block foreign substances introduced from the outside from entering the image sensor.

In an embodiment of the present invention, since the cover can 320 serves as a yoke to prevent leakage of the magnetic field, the number of assembly parts and assembly time of the voice coil motor 600 are greatly reduced, and the voice coil motor 600 Size can also be reduced.

Referring back to FIG. 1, the elastic member 400 includes first elastic members 410 and second elastic members 420.

The first elastic member 410 is made of two, each first elastic member 410 is formed in a symmetrical shape, each of the first elastic member 410 is a coupling protrusion and a base formed on the lower surface of the bobbin 210 It is inserted and fixed to the support column 120 formed in (100).

When fixing the first elastic members 410 by inserting them into the support column 120, the number of parts constituting the voice coil motor 600 additionally is not necessary to use a lower spacer for fixing the first elastic members 410 And assembly time can be reduced.

Each of the first elastic members 410 is electrically connected to both ends of an electric wire constituting the coil block 220. That is, the driving signal applied to the coil block 220 is applied to the coil block 220 through the first elastic members 410.

The second elastic member 420 is coupled to the upper end of the bobbin 210, and the second elastic member 420 is disposed on the magnet 310.

On the other hand, the upper surface of the second elastic member 420 disposed on the upper surface of the magnet 310 in order to fix the second elastic member 420 disposed on the upper surface of the magnet 310 and secure the displacement of the mover 200 Spacers 440 may be disposed in the. The spacer 440 may be formed in a square frame shape, and the upper surface of the spacer 440 is fixed by the upper plate 314 of the cover can 320.

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Embodiment 2

3 is an exploded perspective view showing a voice coil motor according to a second embodiment of the present invention. 4 is an enlarged view of part'A' of FIG. 3. The voice coil motor according to the second embodiment of the present invention is substantially the same as the voice coil motor shown in FIGS. 1 and 2 except for the coupling relationship between the bobbin and the cover can. Accordingly, redundant descriptions of the same components will be omitted, and the same names and the same reference numerals will be assigned to the same components.

Referring to FIGS. 3 and 4, the voice coil motor 600 includes a base 100, a mover 200, a stator 300, and an elastic member 400.

The mover 200 includes a bobbin 210 and a coil block 220, and a stepped 215 for accommodating the magnetic flux leakage preventing portion 316 of the cover can 320 to be described later on the inner surface of the bobbin 210 The rotation preventing groove 222 formed in is formed.

In one embodiment of the present invention, at least one, preferably, a plurality of rotation preventing grooves 222 may be formed in the stepped 215.

The stator 300 includes a magnet 310 and a cover can 320.

The cover can 320 includes a side plate 312, an upper plate 314, and a magnetic flux leakage preventing part 316, and the magnetic flux leakage preventing part 316 is formed in a cylindrical shape to prevent leakage of magnetic flux.

In an embodiment of the present invention, a rotation preventing part 317 is formed at a position corresponding to the rotation preventing groove 222 among the ends of the magnetic flux leakage preventing part 316, and the rotation preventing part 317 is formed in the rotation preventing groove ( 222).

The rotation preventing portion 317 disposed in the rotation preventing groove 222 prevents the bobbin 210 from rotating in the circumferential direction while the mover 200 including the bobbin 210 is up-down.

Embodiment 3

5 is an exploded perspective view showing a voice coil motor according to a third embodiment of the present invention. 6 is an enlarged view of a portion'B' of FIG. 5. The voice coil motor according to the third embodiment of the present invention is substantially the same as the voice coil motor shown in FIGS. 1 and 2 except for the coupling relationship between the bobbin and the cover can. Accordingly, redundant descriptions of the same components will be omitted, and the same names and the same reference numerals will be assigned to the same components.

5 and 6, the voice coil motor 600 includes a base 100, a mover 200, a stator 300, and an elastic member 400.

The mover 200 includes a bobbin 210 and a coil block 220, and a stepped 215 for accommodating the magnetic flux leakage preventing portion 316 of the cover can 320 to be described later on the inner surface of the bobbin 210 The rotation preventing protrusion 224 protruding from the upper surface of the is formed.

In one embodiment of the present invention, at least one, preferably, a plurality of rotation preventing protrusions 224 may protrude from the stepped 215.

The stator 300 includes a magnet 310 and a cover can 320.

The cover can 320 includes a side plate 312, an upper plate 314, and a magnetic flux leakage preventing part 316, and the magnetic flux leakage preventing part 316 is formed in a cylindrical shape to prevent leakage of magnetic flux.

In one embodiment of the present invention, a rotation preventing groove 318 is formed at a position corresponding to the rotation preventing protrusion 224 among the ends of the magnetic flux leakage preventing portion 316, and the rotation preventing groove 318 is a bobbin 210 It is combined with the rotation preventing protrusion 224 formed on the stepped 215 formed on the inner side of the.

The rotation preventing protrusion 224 disposed in the rotation preventing groove 318 rotates the bobbin 210 in the circumferential direction by the elastic member 400 while the mover 200 including the bobbin 210 is up-down. Prevent it from becoming.

Embodiment 4

7 is an exploded perspective view showing a voice coil motor according to a fourth embodiment of the present invention. The voice coil motor according to the fourth embodiment of the present invention is substantially the same as the voice coil motor shown in FIGS. 1 and 2 except for the coupling relationship between the bobbin and the cover can. Accordingly, redundant descriptions of the same components will be omitted, and the same names and the same reference numerals will be assigned to the same components.

Referring to FIG. 7, the voice coil motor 600 includes a base 100, a mover 200, a stator 300, and an elastic member 400.

The mover 200 includes a bobbin 210 and a coil block 220, and a rotation preventing groove 226 formed from the upper surface of the bobbin 210 toward the lower surface of the bobbin 210 on the inner surface of the bobbin 210 Is formed, and a plurality of rotation prevention grooves 226 are intermittently formed on the inner surface of the bobbin 210.

The stator 300 includes a magnet 310 and a cover can 320.

The cover can 320 includes a side plate 312, an upper plate 314, and a magnetic flux leakage preventing part 319, and the magnetic flux leakage preventing part 319 is an inner surface formed by the opening 315 of the upper plate 314 A plurality of intermittently protruding from the magnetic flux leakage preventing portion 319 is formed in a position corresponding to the rotation preventing groove 226 formed on the inner surface of the bobbin 210.

In one embodiment of the present invention, since the magnetic flux leakage preventing portion 319 of the cover can 320 is disposed in the rotation preventing groove 226, it blocks the magnetic field generated from the magnet 310 and the coil block 220 as well as The bobbin 210 is prevented from rotating during the movable operation of the bobbin 210.

As described in detail above, the leakage of the magnetic field generated from the magnet or coil block is prevented to improve the operation efficiency of the mover, and the cover can performs the yoke function together, thereby reducing the number of parts and assembly time, as well as size. Also has a reducing effect.

Although the embodiments according to the present invention have been described above, these are only exemplary, and those of ordinary skill in the art will understand that various modifications and equivalent ranges of embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the following claims.

600...Voice coil motor 100...base
200... mover 300... stator
400...elastic member

Claims (19)

A cover including an upper plate including an opening and a side plate extending from an outer circumference of the upper plate;
A bobbin disposed in the cover;
A base disposed under the bobbin and coupled to the side plate of the cover;
A coil disposed on the bobbin;
A magnet disposed between the coil and the side plate of the cover and facing the coil;
A ground terminal disposed on the base; And
It includes an upper elastic member coupled to the upper portion of the bobbin,
The side plate of the cover is electrically connected to the ground terminal,
The cover includes a rotation preventing portion disposed under the upper plate of the cover in the side plate of the cover,
The bobbin includes a groove formed at a position corresponding to the rotation preventing portion of the cover,
At least a portion of the rotation preventing portion of the cover is disposed in the groove of the bobbin so as to be caught by the bobbin when the bobbin rotates in a circumferential direction
The upper elastic member is a voice coil motor that is not exposed through the opening of the upper plate of the cover. The method of claim 1,
At least a portion of the rotation preventing portion of the cover is disposed in the groove of the bobbin. The method of claim 1,
The rotation preventing portion of the cover includes four rotation preventing portions spaced apart in the circumferential direction of the bobbin,
A voice coil motor having a distance in the circumferential direction between two adjacent rotation preventing portions among the four rotation preventing portions is greater than a length in the circumferential direction of the rotation preventing portion. The method of claim 1,
The at least part of the rotation preventing part of the cover overlaps the bobbin in a circumferential direction of the bobbin. The method of claim 1,
The upper elastic member includes an inner portion coupled to the upper portion of the bobbin, an outer portion disposed between the magnet and the upper plate of the cover, and a connection portion connecting the inner portion and the outer portion,
The at least a portion of the rotation preventing portion of the cover is disposed at a position lower than the position of the inner portion of the upper elastic member. The method of claim 1,
The voice coil motor includes a portion of the bobbin disposed to overlap the rotation preventing portion in a radial direction of the rotation preventing portion. The method of claim 1,
The magnet is disposed at the corner of the cover,
The magnet is a voice coil motor including four magnets corresponding to four corners of the cover. The method of claim 1,
The magnet is a voice coil motor contacting the inner surface of the side plate of the cover. The method of claim 1,
The magnet includes a first surface facing the bobbin and a second surface disposed opposite the first surface,
The voice coil motor having the first surface of the magnet larger than the second surface of the magnet. The method of claim 1,
It includes a lower elastic member coupled to the lower portion of the bobbin,
The lower elastic member includes a first elastic unit and a second elastic unit spaced apart from each other,
A voice coil motor wherein the first elastic unit and the second elastic unit of the lower elastic member are electrically connected to the coil. The method of claim 1,
The base includes a first protrusion protruding from an upper surface of the base, and a second protrusion protruding from the upper surface of the base and spaced apart from the first protrusion,
The side plate of the cover includes first to fourth side plates,
The base includes a first side portion coupled to the first side plate of the cover, a second side portion coupled to the second side plate of the cover, and a first portion disposed between the first side and the second side portion. Including corners,
The first protrusion and the second protrusion of the base are disposed in the first corner of the base. The method of claim 11,
The voice coil motor having a cross-sectional area of the base in a direction perpendicular to an optical axis of the first protrusion is larger than a cross-sectional area of the base in a corresponding direction of the second protrusion. The method of claim 1,
Including a spacer disposed between the bobbin and the cover,
A portion of the upper elastic member is disposed between the magnet and the spacer so as to overlap the magnet and the spacer. The method of claim 11,
It includes a lower elastic member coupled to the lower portion of the bobbin,
The lower elastic member includes a first hole into which the first protrusion of the base is inserted, and a second hole into which the second protrusion of the base is inserted. The method of claim 11,
A first terminal disposed on the base and a second terminal spaced apart from the first terminal,
The first protrusion includes a plurality of first protrusions,
The first terminal and the second terminal are disposed between two first protrusions among the plurality of first protrusions. The voice coil motor of claim 1;
A lens coupled to the bobbin of the voice coil motor; And
A camera including an image sensor disposed under the lens. A smartphone comprising the camera of claim 16. A cover including an upper plate including an opening, a side plate extending downward from an outer circumference of the upper plate, and a plurality of rotation preventing portions extending downward from an inner circumference of the upper plate;
A bobbin disposed in the cover;
A base disposed under the bobbin and coupled to the side plate of the cover;
A coil disposed on the bobbin;
A magnet disposed between the coil and the side plate of the cover and facing the coil;
A ground terminal disposed on the base; And
It includes an upper elastic member coupled to the upper portion of the bobbin,
The side plate of the cover is electrically connected to the ground terminal,
The bobbin includes a plurality of grooves formed in pairs with the plurality of rotation preventing parts at positions corresponding to the plurality of rotation preventing parts of the cover,
At least a portion of the rotation preventing portion of the cover is inserted into the groove of the bobbin to overlap the bobbin in a circumferential direction,
The upper elastic member is not exposed through the opening of the upper plate of the cover voice coil motor. The method of claim 18,
At least a portion of the rotation preventing portion of the cover is disposed in the groove of the bobbin.

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