KR102034195B1 - Voice coil motor - Google Patents

Abstract

The voice coil motor includes a stator including a first driver; A mover disposed inside the stator and including a second driver configured to generate a second magnetic field moved from the stator by a first magnetic field generated from the first driver; A base for fixing the stator; And a first elastic member coupled to a lower portion of the mover so that the mover is spaced apart from the base when a drive signal is not applied to any one of the first and second drive units, and the lower portion of the mover. And an elastic member including a second elastic member coupled to the upper portion, wherein the first and second elastic members have different spring constants K to prevent tilting of the mover by the center of gravity of the mover. Have

Description

Voice coil motor {VOICE COIL MOTOR}

The present invention relates to a voice coil motor.

Recently, mobile phones and the like with built-in miniature digital cameras have been developed.

In the case of a conventional digital camera applied to a mobile phone, the distance between an image sensor and a lens for changing external light into a digital image or a digital image cannot be adjusted, but a voice coil motor for controlling the distance between the image sensor and the lens has recently been The same lens driving device has been developed to enable improved digital images or digital images in ultra-compact digital cameras.

In general, a voice coil motor has a lens mounted therein, and a bobbin disposed at the base moves upward from the base to adjust a gap between the lens and an image sensor disposed at the rear of the base.

In addition, the bobbin of the voice coil motor is coupled to the leaf spring so that the bobbin is always in contact with the base by the elastic force of the leaf spring when the voice coil motor is not operated. That is, the bobbin of the conventional voice coil motor is driven in one direction toward the top with respect to the base.

 In order to drive the voice coil motor by driving the voice coil motor only in one direction, a driving force larger than the self-weight of the bobbin and the elastic force of the leaf spring is required, and thus, the power consumption of the voice coil motor is greatly increased.

In addition, in order to drive the voice coil motor requires a driving force greater than the self-weight of the bobbin and the elastic force of the leaf spring has a problem that the size of the coil wound on the magnet or bobbin is increased to increase the overall size of the voice coil motor.
(Patent Document 1) KR10-2009-0026480 A

The present invention provides a voice coil motor which drives the mover with a smaller current and suppresses or prevents the tilt of the mover generated according to the mover's posture.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

In one embodiment, the voice coil motor includes a stator including a first driver; A mover disposed inside the stator and including a second driver configured to generate a second magnetic field moved from the stator by a first magnetic field generated from the first driver; A base for fixing the stator; And a first elastic member coupled to a lower portion of the mover so that the mover is spaced apart from the base when a drive signal is not applied to any one of the first and second drive units, and the lower portion of the mover. And an elastic member including a second elastic member coupled to the upper portion, wherein the first and second elastic members have different spring constants K to prevent tilting of the mover by the center of gravity of the mover. Have

In one embodiment, the voice coil motor includes a stator including a first driver; A mover disposed inside the stator and including a second driver configured to generate a second magnetic field moved from the stator by a first magnetic field generated from the first driver; A base for fixing the stator; And a first elastic member coupled to a lower portion of the mover so that the mover is spaced apart from the base when a drive signal is not applied to any one of the first and second drive units, and the lower portion of the mover. And an elastic member including a second elastic member coupled to an upper portion, and offsetting the moment of the mover generated by the center of gravity of the mover eccentric to one side from the center of the mover to prevent tilting of the mover. In order to achieve this, the first and second elastic members have different spring constants K.

According to the voice coil motor according to the present invention, the voice coil is floated from the bobbin receiving groove formed on the upper surface of the base on which the lens is mounted, thereby driving the mover in a direction away from the base or approaching the base in both directions. It can drive the motor at low current, reduce power consumption, adjust the focus between the lens and image sensor in less time, reduce the contact noise caused by the bobbin drive, and move the center of gravity of the mover away from the base. This prevents the mover from tilting, thereby improving the quality of the image.

1 is a cross-sectional view conceptually illustrating a voice coil motor according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view showing a specific configuration of the voice coil motor of FIG. 1.
3 is an assembled cross-sectional view of FIG. 2.
4 and 5 are cross-sectional views illustrating a comparison of a voice coil motor according to a first comparative example and an embodiment of the present invention.
6 and 7 are cross-sectional views illustrating comparison of a voice coil motor according to a second comparative example and an embodiment of the present invention.

Hereinafter, exemplary 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 that are specifically defined in consideration of the configuration and operation of the present invention may vary depending on the intention or custom of the user or operator. Definitions of these terms should be interpreted as meanings and concepts corresponding to the technical spirit of the present invention based on the contents throughout the present specification.

1 is a cross-sectional view conceptually illustrating a voice coil motor according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing a specific configuration of the voice coil motor of FIG. 1. 3 is an assembled cross-sectional view of FIG. 2.

1 to 3, the voice coil motor 600 includes a stator 100, a mover 200, a base 300, and an elastic member 400. In addition, the voice coil motor 600 may include a cover can 500.

The stator 100 includes a first driver 120 and a housing 150. The stator 100 generates a magnetic field for driving the mover 200 to be described later.

The first driving unit 120 may include, for example, a coil block formed by winding a long wire insulated by an insulating resin into a cylindrical shape. When a voltage having a voltage difference is applied to the first driver 120 including a coil block formed by winding a long wire insulated by an insulating resin, a first magnetic field is generated from the first driver 120. The direction of the magnetic field is changed according to the direction of the current flowing in the first driver 120.

Although the first driving unit 120 of the stator 100 is a coil block in the exemplary embodiment of the present invention, the first driving unit 120 may include a magnet for generating a magnetic field.

The housing 150 fixes the first driver 120. The housing 150 includes, for example, the housing body 152 and the pillars 154.

The housing body 152 is formed, for example, in a rectangular plate shape, and an opening 153 is formed in the central portion of the housing body 152 to expose a lens mounted on a bobbin to be described later.

The upper surface of the housing body 152 is formed with a plurality of coupling bosses 156 for fixing the elastic member to be described later.

The pillars 154 protrude from the four corners of the lower surface of the housing body 152 facing the base 300, respectively. The inner side surface of the first driving unit 120 including the coil block is fixed to the outer circumferential surface of the pillars 154. Pillars 154 may be coupled to the upper surface of the base 300 to be described later.

In one embodiment of the present invention, the first drive unit 120 including the coil block is attached to the pillars 154 of the housing 150 by an adhesive or the like in a state of winding in a cylindrical shape or a pillar of the housing 150 ( 154 can be wound directly.

The mover 200 includes a bobbin 210 and a second driver 250.

A cylindrical lens 205 is fixed inside the bobbin 210. The mover 200 moves with respect to the stator 100 to adjust the distance between the image sensor and the lens 205 disposed on the lower surface of the base 300 to be described later.

The bobbin 210 is, for example, formed in a cylindrical shape with a hollow, and a thread for fixing the lens 205 is formed on the inner circumferential surface of the bobbin 210.

The outer circumferential surface of the bobbin 210 is formed with flat fixing parts 215 for fixing the second driving parts 250. For example, four fixing parts 215 are formed at equal intervals on the outer circumferential surface of the bobbin 210, for example.

The second driving units 250 may include, for example, a magnet having a plate shape and generating a second magnetic field, and the second driving units 250 may be formed at each fixing part 215 formed on the outer circumferential surface of the bobbin 210. Is fixed to. Each second driver 250 may be attached to the fixing part 215 by an adhesive or the like.

Each second driver 250 is disposed to face the first driver 120 of the stator 100.

Although it is shown and described that the second driving unit 250 is a magnet in an embodiment of the present invention, the second driving unit 250 may alternatively include a coil block formed by winding an insulated long wire.

For example, when the first driver 120 includes a coil block, the second driver 250 includes a magnet. On the contrary, when the first driver 120 includes a magnet, the second driver 250 includes a magnet. Includes a coil block.

The mover 200 is caused by the attraction or repulsive force generated by the first magnetic field generated from the first drive unit 120 of the stator 100 and the second magnetic field generated from the second drive unit 250 of the mover 200. Up-down based on the base 300 to be described later. Meanwhile, in one embodiment of the present invention, the mover 200 is spaced apart from the top surface of the base 300 in a state in which a driving signal is not applied to the first driver 120 or the second driver 250.

The base 300 is, for example, formed in a rectangular plate shape and serves to fix the stator 100.

In the central portion of the base 300 is formed an opening 310 through which light passing through the lens 205 embedded in the bobbin 210 of the mover 200 passes.

Four pillars 325 are formed at four corners of the upper surface 320 of the base 300 formed in a plate shape, and the coupling pillar 325 mutually couples the cover can 500 and the base 300 to be described later. It plays a role.

An IR filter 301 and an image sensor (not shown) for generating an image corresponding to light passing through the lens 205 of the bobbin 210 are fixed to the rear surface of the base 300.

On the other hand, the upper surface 320 of the base 300 is formed with a bobbin receiving groove 330 formed concave from the upper surface 320. The bobbin receiving groove 330 serves to receive the lower end of the bobbin 210.

The bobbin receiving groove 330 may be formed larger than the plane of the bobbin 210, and a part of the bobbin 210 and the base 300 may overlap each other by the bobbin receiving groove 330.

In one embodiment of the present invention, the depth of the bobbin receiving groove 330 may be formed in consideration of the stroke length of the mover 200.

Meanwhile, the shock absorbing member 350 formed along the opening 310 of the base 300 is disposed on the bottom surface 335 of the base 300 formed by the bobbin receiving groove 330. For example, the shock absorbing member 350 absorbs shock and vibration due to the collision between the bobbin 210 and the bottom surface 335 of the base 300.

In one embodiment of the present invention, the shock absorbing member 350 may include any one of a sponge, a synthetic resin having elasticity and rubber, and the shock absorbing member 350 may be formed in an annular plate shape having a thin thickness. Can be.

In one embodiment of the present invention, the movable member 200 in the state that the driving signal is not applied to the first driving unit 120 of the stator 100 and the second driving unit 250 of the mover 200 is an elastic member ( 400 is spaced apart from the top surface of the base 300.

As described above, when the mover 200 is spaced apart from the upper surface of the base 300 in the state in which the driving signal is not applied, the second drive unit 250 of the mover 200 or the first drive unit of the stator 100 ( As the driving signal is applied to any one of the 120, the mover 200 moves in a direction away from the top surface of the base 300 or in a direction closer to the top surface of the base 300. As a result, the strength and power consumption of the current required to drive the movable element 200 can be greatly reduced.

The elastic member 400 for separating the mover 200 from the upper surface of the base 300 includes a first elastic member 440 and a second elastic member 450.

The elastic member 400 is a bottom surface formed by the bobbin receiving groove 330 formed on the lower surface of the bobbin 210 and the upper surface 320 of the base 300 when no driving signal is applied to the second driving unit 250. Space between (335).

The first elastic member 440 elastically supports the lower part of the bobbin 210 of the mover 200, and the bottom of the bobbin 210 of the mover 200 has a base 300 of the first elastic member 440. ) To be floated on top of the bobbin receiving groove 330.

The first elastic member 440 includes a first inner elastic portion 410, a first outer elastic portion 420, and a first connection elastic portion 430.

The first inner elastic part 410 is, for example, formed in an annular ring shape, the first inner elastic part 410 is coupled to the bottom or bottom of the bobbin 210. The first inner elastic part 410 is coupled to the lower surface of the bobbin 210 by, for example, an adhesive or heat welding.

Since the first inner elastic part 410 is coupled to the bottom or bottom of the bobbin 210, the first inner elastic part 410 is also formed to have a size inserted into the bobbin receiving groove 330 of the base 300.

The first outer elastic part 420 is disposed outside the first inner elastic part 410, and the first outer elastic part 420 is formed in a rectangular frame shape.

The first outer elastic part 420 is formed to have a larger size than the bobbin receiving groove 330 of the base 300, and thus the first outer elastic part 420 is disposed on the upper surface 320 of the base 300. The first outer elastic part 420 may be fixed to the upper surface 320 of the base 300 by, for example, the pillars 154 of the housing 150 of the stator 100.

The first connecting elastic part 430 elastically connects the first inner elastic part 410 and the first outer elastic part 420 to each other, and the first inner elastic part 410 by the first connecting elastic part 430. ) Becomes elastic. The first connection elastic part 430 may have a first spring constant K, and the first spring constant K may be changed by the shape, thickness, length, and dimension of the first connection elastic part 430.

Although one embodiment of the present invention is shown and described that the first elastic member 440 is formed as one, alternatively, the first elastic member 440 is a symmetrical shape of the pair of the lower surface of the bobbin 210 It can be combined.

The second elastic member 450 is coupled to the coupling boss 156 formed on the upper surface of the housing body 152 of the housing 150 of the stator 100.

The second elastic member 450 includes a second inner elastic portion 451, a second outer elastic portion 452, and a second connection elastic portion 453.

The second inner elastic portion 451 is coupled to the top or top of the bobbin 210, the second outer elastic portion 452 is disposed on the upper surface of the housing body 152. The second connecting elastic portion 453 interconnects the second outer and second inner elastic portions 451 and 452, and the second connecting elastic portion 453 has a second spring constant K. FIG. The second spring constant K of the second connection elastic portion 453 may be changed by the shape, thickness, length, and dimension of the second connection elastic portion 453.

The second outer elastic part 452 disposed on the upper surface of the housing body 152 is formed with a coupling hole 455 that is engaged with the coupling boss 156 formed on the upper surface of the housing body 152.

Referring back to FIG. 2, the voice coil motor 600 may further include a cover can 500.

The cover can 500 includes a top plate 510 having an opening for exposing the lens 205 of the mover 200 and a side plate 520 extending in a direction from the edge of the top plate 510 toward the base 300. It includes, the side plate 520 is coupled to the side of the base 300.

Referring to FIG. 1 again, the bobbin 210 of the mover 200 according to an embodiment of the present invention may be formed of the base 300 by the force generated from the first driver 120 and the second driver 250. Driving in a first direction FD away from the upper surface 320 of the first direction FD and in a second direction SD facing the bottom surface of the bobbin accommodation groove 330 of the base 300 in a direction opposite to the first direction FD. Can be.

In one embodiment of the present invention, the bobbin 210 of the mover 200 is driven in the first direction FD when the forward current is applied to the first driver 120, for example, the bobbin 210. ) Is driven in a second direction SD opposite to the first direction when a reverse current opposite to the forward current is applied to the first driver 120.

In this case, the forward current or the reverse current applied to the first driver 120 may be implemented by adjusting the voltage difference applied to both ends of the first driver 120.

The voice coil motor 600 shown in FIGS. 1 to 3 is arranged when the optical axis of the lens 205 is disposed perpendicular to the ground (or horizontal plane), that is, the voice coil motor 600 is on the ground (or horizontal plane). In a correctly placed state, the mover 200 of the voice coil motor 600 is disposed without tilt in a direction perpendicular to the ground.

However, when a user photographs an object using a smart phone equipped with the voice coil motor 600, the voice coil motor 600 is arranged in various directions. For example, when the optical axis of the lens 205 mounted on the mover 200 of the voice coil motor 600 is directed in a direction parallel to the ground (or horizontal plane), the optical axis moves along the center of gravity of the mover 200. The ruler 200 has a moment acting according to the gravity and the position of the center of gravity of the mover 200, thereby causing the tilt of the mover 200 to be generated.

In one embodiment of the present invention, the voice coil motor 600 suppresses or prevents the tilt of the mover 200 generated as the posture or arrangement is changed with respect to the reference plane (ground or horizontal plane).

In order to suppress or prevent the tilt of the mover 200 in accordance with the change in the posture or the arrangement of the voice coil motor 600, the first elastic member 440 of the elastic member 400 elastically supporting the mover 200. ) And the second elastic member 450 have different spring constants (K) corresponding to the center of gravity of the mover (200).

Although in one embodiment of the present invention is shown and described that the first and second elastic members 440, 450 have different spring constants K in correspondence to the center of gravity of the mover 200, the mover 200 It is also possible for the first and second elastic members 440 and 450 to have different modulus of elasticity (E) with respect to the center of gravity.

4 is a cross-sectional view illustrating a voice coil motor according to a comparative example compared to a voice coil motor according to an embodiment of the present invention.

Referring to FIG. 4, the mover 200a is coupled to the stator 100a by elastic members 440a, 450a; 400a, and the mover 200a of the base 300a when the drive signal is not applied. Spaced apart from the top surface. In the comparative example, the first elastic member 440a and the second elastic member 450a of the elastic member 400a each have the same elastic modulus E and the same spring constant K, respectively. Further, in the comparative example, the center of gravity G of the mover 200a is formed at a position spaced toward the top of the mover 200a by the length of L1 with respect to the center C of the mover 200a. .

In the comparative example, when the optical axis of the mover 200a of the voice coil motor 600a is disposed parallel to the ground, that is, the elastic member 400a is directed toward the second direction SD which is a direction perpendicular to the ground. When arranged, the moment (M) due to the weight of the mover (200a) is generated in the center of gravity (G) of the mover (200a), the mover (200a) is a moment (M) generated in the clockwise direction Tilt by.

In the comparative example, as the movable member 200a is tilted, the optical axis of the lens may not coincide with the optical axis of the image sensor, which may cause serious image generation failure.

5 is a cross-sectional view illustrating a voice coil motor according to an embodiment of the present invention as compared with the comparative example shown in FIG. 4.

Referring to FIG. 5, the mover 200 is coupled to the stator 100 by elastic members 440, 450 and 400, and the mover 200 is moved from the top surface of the base 300 when no drive signal is applied. Spaced apart. The first elastic member 440 and the second elastic member 450 of the elastic member 400 have different spring constants K. In addition, the center of gravity G of the mover 200 is spaced toward the top of the mover 200 by the length of L1 based on the center C of the mover 200 as in the comparative example of FIG. 4. Formed in position.

When the optical axis of the mover 200 of the voice coil motor 600 is disposed parallel to the ground, that is, when the elastic member 400 is disposed toward the second direction SD which is a direction perpendicular to the ground, In the center of gravity G of the mover 200, a moment M due to the weight of the mover 200 is generated, but in one embodiment of the present invention, as shown in the comparative example of FIG. Tilt of 200) is not generated.

This is because the first and second elastic members 440 and 450 have different spring constants K as described above in order to prevent the tilt of the mover 200 by the center of gravity G of the mover 200. to be.

Specifically, when the center of gravity G of the mover 200 is formed to be close to the second elastic member 450 based on the center C of the mover 200, the first elastic member 440 may be formed. While having a first spring constant K1, the second elastic member 450 is greater than the first spring constant K1 of the first elastic member 440 to offset the moment to prevent tilting of the mover 200. Has a second spring constant K2.

In one embodiment of the present invention, the second spring constant K2 has a value suitable for canceling the moment for tilting the mover 200, and the second spring constant K2 is the center of the mover 200. C) and may be increased in proportion to the length L1 between the center of gravity G of the mover 200. Alternatively, the first spring constant K1 of the first elastic member 440 may be reduced in inverse proportion to the second spring constant K2.

In one embodiment of the present invention, the second elastic member 440 has a first spring constant K1 and the second elastic member 450 has a second spring constant K2 greater than the first spring constant K1. In order to have a first elastic member 440 is formed in a first cross-sectional area, the second elastic member 450 may be formed in a second cross-sectional area larger than the first cross-sectional area.

In addition, in order that the first elastic member 440 has the first spring constant K1 and the second elastic member 450 has the second spring constant K2 greater than the first spring constant K1, The first connecting elastic portion 430 of the first elastic member 440 is formed to have a first length, and the second connecting elastic portion 453 of the second elastic member 450 has a second length longer than the first length. Is formed.

In addition, in order that the first elastic member 440 has the first spring constant K1 and the second elastic member 450 has the second spring constant K2 greater than the first spring constant K1, The first connection elastic portion 430 of the first elastic member 440 and the second connection elastic portion 453 of the second elastic member 450 may be formed in different shapes.

6 is a cross-sectional view of the voice coil motor according to Comparative Example 2 as compared to the voice coil motor according to an embodiment of the present invention.

Referring to FIG. 6, the mover 200b is coupled to the stator 100b by elastic members 440b, 450b and 400b, and the mover 200b of the base 300b when the drive signal is not applied. Spaced apart from the top surface. In Comparative Example 2, the first elastic member 440b and the second elastic member 450b of the elastic member 400b each have the same elastic modulus E and the same spring constant K, respectively. In Comparative Example 2, the center of gravity G of the mover 200b is formed at a position spaced toward the lower end of the mover 200b by the length of L1 based on the center C of the mover 200b. do.

In Comparative Example 2, when the optical axis of the mover 200b of the voice coil motor 600b is disposed in parallel with the ground, that is, the elastic member 400b is arranged in a second direction SD which is perpendicular to the ground. When disposed toward the center of gravity of the mover (200b), the moment (M) due to the weight of the mover (200b) is generated, the mover (200b) is generated in the counterclockwise direction ( Tilt by M).

In Comparative Example 2, as the movable member 200b is tilted in the counterclockwise direction, the optical axis of the lens does not coincide with the optical axis of the image sensor, which may cause serious image generation failure.

FIG. 7 is a cross-sectional view illustrating a voice coil motor according to an embodiment of the present invention as compared with Comparative Example 2 shown in FIG. 6.

Referring to FIG. 7, the mover 200 is coupled to the stator 100 by elastic members 440, 450 and 400, and the mover 200 is moved from the top surface of the base 300 when no driving signal is applied. Spaced apart. The first elastic member 440 and the second elastic member 450 of the elastic member 400 have different spring constants K. In addition, the center of gravity G of the mover 200 is spaced toward the lower end of the mover 200 by the length of L1 based on the center C of the mover 200 as in Comparative Example 2 of FIG. 6. Formed in a closed position.

When the optical axis of the mover 200 of the voice coil motor 600 is disposed parallel to the ground, that is, when the elastic member 400 is disposed toward the second direction SD which is a direction perpendicular to the ground, In the center of gravity G of the mover 200, a moment M due to the weight of the mover 200 is generated, but in one embodiment of the present invention, as shown in the comparative example of FIG. Tilt of 200) is not generated.

This is because the first and second elastic members 440 and 450 have different spring constants K as described above in order to prevent the tilt of the mover 200 by the center of gravity G of the mover 200. to be.

Specifically, when the center of gravity G of the mover 200 is formed to be close to the first elastic member 440 based on the center C of the mover 200, the second elastic member 450 may be formed of the second elastic member 450. While having a two spring constant (K2), the first elastic member 440 is greater than the second spring constant (K2) of the second elastic member 450 to cancel the moment to prevent the tilt of the mover (200) It has a first spring constant K1.

In one embodiment of the present invention, the first spring constant K1 of the first elastic member 440 has a value suitable for canceling the moment M for tilting the mover 200, the first spring constant ( K1) may be increased in proportion to the length L1 between the center C of the mover 200 and the center of gravity G of the mover 200. Alternatively, the second spring constant K2 of the second elastic member 450 may be reduced in inverse proportion to the first spring constant K1.

In one embodiment of the present invention, the first elastic member 450 has a second spring constant K2, and the first elastic member 440 has a first spring constant K1 greater than the second spring constant K2. In order to have a first elastic member 440 is formed in a first cross-sectional area, the second elastic member 450 may be formed in a second cross-sectional area smaller than the first cross-sectional area.

In addition, in order that the first elastic member 440 has the first spring constant K1 and the second elastic member 450 has the second spring constant K2 greater than the first spring constant K1, The first connecting elastic part 430 of the first elastic member 440 is formed to have a first length, and the second connecting elastic part 453 of the second elastic member 450 has a second length shorter than the first length. Is formed.

In addition, in order for the second elastic member 450 to have a second spring constant K2, and the first elastic member 450 to have a first spring constant K1 larger than the second spring constant K2, The first connection elastic portion 430 of the first elastic member 440 and the second connection elastic portion 453 of the second elastic member 450 may be formed in different shapes.

As described above, in order to prevent tilting of the movable member, a technique of individually adjusting the spring constants K of the first elastic member 440 and the second elastic member 450 coupled to the upper and lower ends of the movable member is disclosed. Alternatively, however, the inherent elastic modulus E of the first and second elastic members 440 and 450 may be changed to prevent tilting of the mover.

As described in detail above, the voice coil motor is driven by floating the bobbin mounted with a lens from the bobbin accommodation groove formed on the upper surface of the base on which the image sensor is mounted and driving the mover in a direction away from the base or approaching the base. Low current reduces drive and power consumption, adjusts focus between lens and image sensor in less time, reduces contact noise caused by bobbin drive, and is driven by the center of gravity of the mover away from the base It has the effect of improving the quality of the image by preventing self tilting.

Although embodiments according to the present invention have been described above, these are merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments of the present invention are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the following claims.

600 ... Voice Coil Motor 100 ... Stator
200 ... operator 300 ... base
400 ... elastic member 500 ... cover can

Claims (20)

A cover comprising a top plate and a side plate extending from the top plate;
A bobbin disposed in the cover;
A coil disposed on the bobbin;
A magnet disposed in the cover and facing the coil;
A housing disposed between the bobbin and the cover;
A base disposed below the bobbin and coupled to the side plate of the cover;
A first elastic member coupled to the bobbin; And
A second elastic member connected to the housing and the bobbin and disposed above the first elastic member,
The first elastic member includes a first outer portion disposed on an upper surface of the base, a first inner portion coupled to the bobbin, and a first connection elastic portion connecting the first outer portion and the first inner portion,
The second elastic member includes a second outer portion coupled to the upper surface of the housing, a second inner portion coupled to the bobbin, and a second connection elastic portion connecting the second outer portion and the second inner portion,
The spring constant of the first connection elastic portion of the first elastic member is different from the spring constant of the second connection elastic portion of the second elastic member,
And the housing includes a first surface disposed at a position lower than a position of the upper surface of the housing at a position corresponding to the second connection elastic portion of the second elastic member. The method of claim 1,
And the upper surface of the housing and the first surface of the housing form a step. The method of claim 1,
And a second connecting elastic part of the second elastic member overlapping the first surface of the housing in a direction parallel to the optical axis. The method of claim 1,
The housing includes a coupling boss projecting from the top surface of the housing,
And the upper surface of the housing is spaced apart from the upper plate of the cover by the coupling boss. The method of claim 4, wherein
And a second connecting elastic part of the second elastic member spaced apart from the upper plate of the cover upward and spaced apart from the first surface of the housing downward. The method of claim 1,
The voice coil motor is spaced apart from the upper plate of the cover and spaced apart from the base to the lower side when no current is applied to the coil. The method of claim 1,
The voice coil motor is disposed below the position of the first outer portion along the optical axis direction with respect to the first outer portion of the first elastic member by the bobbin movement. . The method of claim 1,
The voice coil motor is disposed below the position of the second outer portion along the optical axis direction with respect to the second outer portion of the second elastic member due to the movement of the bobbin. . The method of claim 1,
The voice coil motor of the first elastic member of the first elastic member has a spring constant greater than the spring constant of the second elastic member of the second elastic member. The method of claim 1,
The length of the first connection elastic portion of the first elastic member is shorter than the length of the second connection elastic portion of the second elastic member voice coil motor. The method of claim 1,
The voice coil motor of claim 1, wherein the first connecting elastic part of the first elastic member and the second connecting elastic part of the second elastic member are formed in different shapes. The method of claim 1,
When a forward current is applied to the coil, the first elastic member is positioned such that the position of the first inner portion of the first elastic member is higher than that of the first outer portion of the first elastic member. Voice coil motor in which the connecting elastic portion is deformed. The method of claim 12,
When a reverse current is applied to the coil, the first elastic member is positioned such that the position of the first inner portion of the first elastic member is lower than that of the first outer portion of the first elastic member. Voice coil motor in which the connecting elastic portion is deformed. An image sensor;
The voice coil motor of claim 1; And
And a lens coupled to the bobbin of the voice coil motor and spaced apart from the image sensor. A mobile phone comprising the camera of claim 14. A cover comprising a top plate and a side plate extending from the top plate;
A bobbin disposed in the cover;
A first driving part disposed on the bobbin;
A second driving part disposed in the cover and facing the first driving part;
A housing disposed between the bobbin and the cover;
A base disposed below the bobbin and coupled to the side plate of the cover;
A first elastic member coupled to the bobbin; And
A second elastic member connected to the housing and the bobbin and disposed above the first elastic member,
The first elastic member includes a first outer portion disposed on an upper surface of the base, a first inner portion coupled to the bobbin, and a first connection elastic portion connecting the first outer portion and the first inner portion,
The second elastic member includes a second outer portion coupled to the upper surface of the housing, a second inner portion coupled to the bobbin, and a second connection elastic portion connecting the second outer portion and the second inner portion,
The spring constant of the first connection elastic portion of the first elastic member is different from the spring constant of the second connection elastic portion of the second elastic member,
The housing includes a coupling boss projecting from the top surface of the housing,
And the second connecting elastic part of the second elastic member is spaced apart from the upper plate of the cover upward and spaced apart from the housing downward. The method of claim 16,
And the upper surface of the housing is spaced apart from the upper plate of the cover by the coupling boss. The method of claim 16,
And the housing includes a first surface disposed at a position lower than a position of the upper surface of the housing at a position corresponding to the second connection elastic portion of the second elastic member. The method of claim 16,
The first driving unit includes a coil and the second driving unit includes a magnet. The method of claim 18,
And a second connecting elastic part of the second elastic member overlapping the first surface of the housing in a direction parallel to the optical axis.

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