KR20120045846A - Voice coil module - Google Patents

Abstract

PURPOSE: A voice coil module is provided to decrease heat added to a magnet through minimizing a contact between a printing circuit substrate and a Shield Can or yoke because a separate ground connector is added. CONSTITUTION: A voice coil module comprises a lens barrel(110), a carrier(120), a coil(130), a magnet, an elastic member(150), a housing(160), a printing circuit substrate(170), a Shield Can(190), and a ground connector(180). The carrier houses the lens barrel. The magnet is arranged in the outer circumference of the coil, thereby forming a magnetic field. The elastic members are respectively arranged in the upper and lower parts of the carrier, thereby controlling the movement up and down of the lens barrel. The housing is arranged in the lower part of the carrier. The printing circuit substrate is arranged in the lower part of the housing. The Shield Can is arranged in the upper part of the carrier. The ground connector electrically connects the printing circuit substrate and Shield Can.

Description

Voice coil module {Voice Coil Module}

The present invention relates to a voice coil module used for an auto focusing device in a mobile communication terminal, and more particularly, to a voice coil module providing a ground connector for easily coupling a voice coil module and an external circuit board.

In general, a camera is provided with a plurality of lenses, a machine capable of photographing a subject through the lens, is typically configured to adjust the focus by adjusting the relative distance between the plurality of lenses. Conventionally, as a device for automatically adjusting the focus of a camera, a mechanical device for changing the rotational motion of a motor into a linear motion through a gear or the like has been used. However, in the case of such a mechanical device, not only it is difficult to finely adjust the focus due to the friction force between the gear and the motor, but also it is difficult to miniaturize due to the space problem occupied by each mechanical device.

In particular, in recent years, a camera module is installed in a mobile communication device such as a mobile phone or a PDA, and is configured to take a still image.The permanent magnet and Camera modules are being developed, such as the camera's automatic focusing device, which uses the coil's induction magnetic force to focus precisely.

Actuators for Auto Focusing Devices There are largely voice coil actuators using Lorentz Force and piezo actuators using piezoelectric effects. There are attempts to use other shape gear alloys, magnetic polymers, and MEMS structures, but at present, two types of actuators occupy most of the entire market.

 Voice coil actuators are simple in structure and have advantages in cost, and piezo actuators have advantages in driving stability and power consumption. Voice coil actuators are used for relatively low pixel ISMs due to their cost, while piezo actuators are used mainly for high pixel.

When the auto focus function is implemented, the position of the image of the subject imaged by the image sensor is changed according to the position of the subject. That is, the position of the image is changed according to the distance between the subject and the lens. In order to implement, one or more lenses may be moved relative to each other. Configured in this way

In order to realize a focusing function in a lens, as a separate driving source, for example, a manual, a step motor, a piezoelectric element, a voice coil module (VCM), etc. are requested, and in particular, a VCM is widely used. In the case of the auto focusing device using the VCM method, the magnet that generates the magnetic force and the coil to which the current is supplied are generally arranged opposite to move the lens position by using the Lorentz force generated in the vertical direction between the current and the magnetic field. To drive the lens barrel.

However, high resolution image sensors such as CCD and CMOS have been commercialized in camera modules applied to mobile communication devices, and the lens assembly of the camera module is also required to be miniaturized according to the miniaturization and high precision of the corresponding lens. . However, when the camera module is to be manufactured in order to satisfy such a miniaturization, light weight, and low cost, the conventional voice coil module uses a printed circuit board and a voice coil module for electrical connection between the printed circuit board 15 and the voice coil module. Were joined by welding.

Also, in recent years, shield cans or yokes are often required to be connected to the printed circuit board of the camera by soldering in order to block electromagnetic waves generated from sensors and ICs.

In the case of the shield can or yoke of the voice coil actuator, the magnetic flux of the magnet is prevented from leaking to the outside and the magnetic efficiency is also increased. However, when soldering directly to the shield can or yoke, the magnet is in contact with the shield can or the yoke due to the high temperature. The phenomenon of deterioration occurs.

Accordingly, an object of the present invention is to solve the above-mentioned disadvantages and problems that may occur in a voice coil module, and by adding a separate ground connector, a printed circuit board, a shield can, or a yoke. It is to provide a voice coil module that can reduce the heat applied to the magnet by minimizing the contact with).

The object of the present invention is a lens barrel; A carrier accommodating the lens barrel therein; a coil coupled to an outer circumferential surface of a carrier; A magnet disposed on an outer circumferential surface of the coil to form a magnetic field; An elastic member disposed on the upper and lower sides of the carrier to constrain the vertical movement of the carrier and the lens barrel; A housing located below the carrier; A printed circuit board positioned below the housing; A shield can positioned above the carrier; And it is achieved by providing a voice coil module including a ground connector for electrical connection of the printed circuit board and the shield can.

In addition, the housing may be provided with a housing connecting portion in which the ground connector is inserted into the lower body.

In addition, the housing connecting portion may be formed at both sides of the lower body of the housing.

In addition, the shield can may be provided with a shield can connection portion in contact with the ground connector.

In addition, the shield can connecting portion may be formed to extend to the lower side toward the printed circuit board.

In addition, the ground connector may be provided with an elastic contact portion in which both sides of the protruding surface are formed in an uneven form.

The elastic contact portion of the ground connector may contact the shield can connecting portion, and both sides of the elastic contact portion may contact the housing connecting portion.

In addition, the ground connector may be made of a conductive metal plate.

In addition, the elastic member may include a leaf spring.

In addition, a connection pad may be formed at one side of the printed circuit board to be electrically connected to the ground connector disposed in the recess of the housing.

In addition, the coil may include at least one of copper (Cu), aluminum (Al), gold (Au), and silver (Ag).

Voice coil module according to an embodiment of the present invention can add a separate ground connector, to minimize the contact between the printed circuit board and the shield can or yoke can reduce the heat applied to the magnet Provide a method.

1 is an exploded perspective view of a voice coil module according to an embodiment of the present invention;
2 to 3 is a voice coil module assembly according to an embodiment of the present invention shown

Embodiments of the present invention will be described in detail with reference to the drawings of the voice coil module. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention.

Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of an apparatus may be exaggerated for convenience. Like numbers refer to like elements throughout.

Hereinafter, a voice coil module according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is an exploded perspective view of a voice coil module according to an embodiment of the present invention, Figures 2 to 3 is an assembled view of the voice coil module according to an embodiment of the present invention shown in FIG.

1 to 3, the voice coil module 100 according to an embodiment of the present invention may include a carrier 120 accommodating the lens barrel 110, a housing 160 positioned below the carrier, and printing. The circuit board 170 may include a shield can 190 positioned above the carrier, and a ground connector 180 for electrical connection between the housing 160 and the shield can 190.

The lens barrel 110 is composed of at least one lens (not shown). The number of lenses accommodated in the lens barrel 110 can be arbitrarily adjusted, and a plurality of lenses are housed in the lens barrel 110 so that the optical axes of each lens coincide. The lens barrel 110 is inserted into the carrier 120 which is linearly moved to adjust the focus by linearly moving with the carrier 120.

The carrier 120 is formed in a hollow cylindrical shape so that the lens barrel 110 can be accommodated therein. In addition, the lens barrel 110 is coupled to the inside of the carrier 120 such that the carrier 120 and the lens barrel 110 perform linear movement integrally.

As described above, in order to couple the lens barrel 150 and the carrier 120, threads may be formed on the outer circumferential surface of the lens barrel 110 and the inner circumferential surface of the carrier 120, respectively. In addition, coupling holes are formed in the lens barrel 150 and the carrier 120, respectively, so that the lens barrel 150 and the carrier 120 may be coupled by separate fastening members. In addition, although screw connection is illustrated as a coupling relationship between the lens barrel 150 and the carrier 120, the spirit of the present invention is not limited thereto, and the lens barrel 150 and the carrier 120 may be coupled to each other. It will be apparent that various combination forms are within the scope of the present invention.

The coil 130 generates an electric field when an external power source is applied through the printed circuit board 170 to interact with the magnetic field of the magnet 140 to linearly drive the carrier 120. The straight line of the carrier 120 By driving, the lens barrel 110 captures a subject while zooming in or zooming out.

The magnet 140 may be attached to the inner wall of the shield can 190 or to the outside of the carrier 120, which is divided into one or a plurality of parts, and formed in the magnetic field formed by the magnet 140. The induced magnetic force of the coil 130 is generated to enable the linear motion of the carrier 120, the coil 130, and the lens barrel 110. In the drawings, the magnet 140 is divided into four pieces to enclose the carrier 120, but the spirit of the present invention is not limited thereto. For convenience of design and manufacturing of the voice coil module 100 or an environment of use, Accordingly, it will be apparent that the number and characteristics of the magnets 140 can be changed. In addition, the shield can 190 including the magnet 140 mainly takes the form of a square, but may be manufactured in various forms such as a circle as long as it does not affect the configuration of the magnetic circuit.

The elastic member 150 is installed on the upper portion of the carrier 120 by a kind of suspension to restore the carrier 120 linearly moving by the interaction between the magnet 140 and the coil 130. However, the type and material of the elastic member 150 is not limited, and it will be apparent that the number and characteristics of the elastic member 150 may be changed according to the design and manufacturing convenience or the use environment of the voice coil module 100. .

The housing 160 is located on the lower side of the carrier, and forms a hexahedron including a lower body 163 and an upper body 162 as a basic base forming the outline of the voice coil module 100. The top is provided in an open form.

A filter is attached to the bottom of the housing 160 to remove wavelengths in the near infrared region, and an IR filter (not shown) is typically used. A printed circuit board having a plurality of patterns is attached to a lower portion of the lower body 163 to which the IR filter is attached to apply an external power to the voice coil module 100, and transmit an electrical signal. The wavelength of the near infrared region of the signal is caught and removed by the IR filter.

The housing connecting portion 161 may include a housing connecting portion 161 having a depression formed at one side of the lower body 163 of the housing 160, and the housing connecting portion 161 may include a ground connector 180 which will be described below. Inserted into the joint.

The shield can 190 is formed in a hollow box to form a hollow portion therein, and the lens barrel 110, the carrier 120, the coil 144, and the magnet 140 described above are accommodated in the hollow portion. do. In addition, the shield can 190 has a shield can connecting portion 191, the shield can connecting portion 191 is located at the lower end of the shield can 190, the lower side facing the printed circuit board 170. The shield can connecting portion 191 may be in contact with the elastic contact portion 181 of the ground connector 180 to be described below. In addition, the groove formed in the shield can connecting portion 191 is coupled to the coupling protrusion 164 installed on one side of the upper body 162 of the housing, the lens barrel 110, the carrier 120, the coil 130, the magnet 140 and the like does not remove to the outside serves to secure to be fixed stably.

The ground connector 180 is for preventing the thermal radiation of the magnet 140 in contact with the shield can 190, that is, shield can 190 to block electromagnetic waves (EMI) generated from sensors, ICs, and the like. Is coupled to the printed circuit board 170, the thermal reduction of the magnet 140 in contact with the shield can 190 is generated, the magnetic efficiency is lowered.

In order to prevent this, the ground connector 180 may be provided to minimize the contact between the shield can 190 and the printed circuit board 170 to reduce heat applied to the magnet 140.

The ground connector 170 is a conductive metal thin film, and forms an elastic contact portion 181 at a central portion thereof, and the elastic contact portion may be formed in an uneven form, but the elastic contact portion 181 may be manufactured in an uneven form. The elastic contact portion 181 is not limited to the irregularities, and it will be apparent that the elastic contact portion 181 may be changed into a protruding shape having a bend.

The ground connector 170 may be in contact with the housing connection part 161, and the elastic contact part 181 of the ground connector 180, which is in contact with the housing connection part 161, may contact the shield can 190. The shield can contact 191 is formed into the inside. In addition, both side portions of the ground connector 180 except for the elastic contact portion 181 may be in contact with the connection pad 171, which may be electrically connected to the printed circuit board 170 and the ground connector 180. It can be done.

The elastic contact portion 181 of the ground connector 180 in contact with the shield can connecting portion 191 may be coupled to the shield can connecting portion 191 by using a conductive bond as well as mechanical contact.

The foregoing detailed description illustrates the present invention. In addition, the foregoing description merely shows and describes preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, it is possible to make changes or modifications within the scope of the concept of the invention disclosed in this specification, the disclosure and the equivalents of the disclosure and / or the scope of the art or knowledge of the present invention. The foregoing embodiments are intended to illustrate the best state in carrying out the present invention, and to utilize other inventions such as the present invention in other conditions known in the art, as well as in specific applications and uses of the invention. Various changes are possible. Accordingly, the detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to include other embodiments.

100: voice coil module
110: lens barrel
120: carrier
130: coil
140: magnet
150: elastic member
160: housing
161: housing connection
162: upper body
163: lower body
170: printed circuit board
171: connection pad
180: ground connector
181: elastic contact
190: shield can
191: shield can connection

Claims (11)

Lens barrels;
A carrier accommodating the lens barrel therein;
A coil coupled to the outer circumferential surface of the carrier;
A magnet disposed on an outer circumferential surface of the coil to form a magnetic field;
An elastic member disposed on the upper and lower sides of the carrier to constrain the vertical movement of the carrier and the lens barrel;
A housing located below the carrier;
A printed circuit board positioned below the housing;
A shield can positioned above the carrier; And
Voice coil module including a ground connector for electrical connection of the printed circuit board and the shield can.
The method of claim 1,
The housing is a voice coil module having a housing connecting portion for inserting the ground connector in the lower body.
The method of claim 1,
The voice coil module is formed on both sides of the lower body of the housing connecting portion.
The method of claim 1,
The shield can is a voice coil module formed with a shield can connection portion to which the ground connector is in contact.
The method of claim 4, wherein
The shield can connecting portion extends to the lower side toward the printed circuit board.
The method of claim 1,
The ground connector is a voice coil module having an elastic contact portion formed on both sides of the projecting surface in the form of irregularities.
The method according to claim 6,
And the elastic contact portion of the ground connector is in contact with the shield can connecting portion, and both sides of the elastic contact portion are in contact with the housing connecting portion.
The method of claim 7, wherein
The ground connector is a voice coil module made of a conductive metal plate.
The method of claim 1,
The elastic member is a voice coil module comprising a leaf spring.
The method of claim 1,
A voice coil module having a connection pad formed at one side of the printed circuit board to be electrically connected to a ground connector disposed in the recess of the housing.
The method of claim 1,
The coil comprises at least one of copper (Cu), aluminum (Al), gold (Au), and silver (Ag).

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