Multi wireless charging apparatus and method for manufacturing the same

The multi wireless charging apparatus of the present invention includes a control unit generally controlling a wireless charging procedure; a plurality of wireless charging units electrically connected to the control unit; and folding units connecting between the wireless charging units, the folding units each having a void therein, which passes through both lateral surfaces thereof, and thereby to be folded up or down.Also, in the multi wireless charging apparatus of the present invention, each of the wireless charging units includes a shielding film made of a conductive material, such as conductive paste or ferrite, and formed on a lower surface thereof, for electromagnetic field shielding.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2011-0109544, filed on Oct. 25, 2011, entitled “Multi Wireless Charging Apparatus and Method for Manufacturing the Same”, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a multi wireless charging apparatus and a method for manufacturing the same.

2. Description of the Related Art

In a wireless charging technology, power necessary for charging a battery is transmitted wirelessly without a power code or a connector for charging. This technology is applied only to limited uses, such as an electric toothbrush, a wireless telephone for home use, electric tools, and the like, in the prior art.

However, the use of the wireless charging technology is increasingly expanding, with a recent explosive increase of the smart phone markets. Smart phones allow users to enjoy various contents and multimedia freely at any time, but there is a limit to the usage time thereof due to limitation in battery capacity. The wireless charging technology in the smart phone market has largely changed since 2010, after a smart phone wirelessly charged appeared. In 2011, products mounting wireless charging modules for wirelessly charging a cellular phone and a smart phone are successively being reported domestically and internationally.

Since the wireless power consortium (WPC), which aims at broadening the use of non-contact type standards, reported the first standard features for devices with 5 W or lower in July, 2010, more and more manufactures are joining this consortium. The wireless charging technology, of which a market is expanding due to employment of the smart phone, is expected to be increasingly applied to high-power devices such as a digital camera, a tablet PC, a monitor, a digital TV, and the like, in the future.

Among several methods enabling wireless charging, an electromagnetic induction method is excellent in view of commercialization and practicality. The electromagnetic induction method, as disclosed in Korean Patent Laid-Open Publication No. 2010-0094197 (laid-open published on Aug. 26, 2010), uses the combination of electromagnetic energy generated from a coil wound several times.

This embodies products based on Faraday's rule that an electromagnetic field generated by a coil on which AC or high-frequency current flows induces electromotive force at an output terminal of an adjacent coil. When a general cellular phone, a smart phone, a digital camera, a tablet PC, a monitor, a notebook, or the like, on which a wireless charging receiving module is mounted, is placed on a charging surface of a wireless charger constituted of a wireless charging transmitting module, an analog circuit, a power circuit, a control circuit, a rectifying circuit, a charging circuit, and the like are run, and thereby charge a battery installed in a device.

However, this wireless charging apparatus is inconvenient to keep and carry out due to a large volume thereof, and it is difficult to wirelessly charge a plurality of devices at the same time.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a multi wireless charging apparatus allowing a folding type and having a slim thickness.

Also, the present invention has been made in an effort to provide a method for manufacturing the multi wireless charging apparatus.

According to one preferred embodiment of the present invention, there is provided a multi wireless charging apparatus, including: a control unit generally controlling a wireless charging procedure; a plurality of wireless charging units electrically connected to the control unit; and folding units connecting between the wireless charging units, the folding units each having a void therein, which passes through both lateral surfaces thereof, and thereby to be folded up or down.

The wireless charging unit may include a shielding film made of a conductive material and formed on a lower surface thereof, for electromagnetic field shielding.

The conductive material may be conductive paste or ferrite.

The folding units each may have the void between at least two double-sided FCCLs, and be folded up or down to allow the plurality of wireless charging units to be stacked in a joining type.

The wireless charging unit may include: at least one rigid base layer; and double-sided flexible copper clad laminates (FCCLs) bonded on an upper surface or a lower surface of the rigid base layer by using the rigid base layer therebetween, wherein the double-sided FCCLs each have a circuit layer formed on an upper surface or a lower surface thereof.

The rigid base layer may be formed by using a prepreg in which a glass fiber is impregnated with a thermosetting resin.

The circuit layer may include: a coil pattern consisting of closed loops; a first end disposed inside the coil pattern; a first electrode pattern spaced apart from the first end and disposed outside the closed loops of the coil pattern; and a wiring pattern electrically connecting the first end and the first electrode pattern through a first conductive via hole H1and a second conductive via hole H2passing through the double-sided FCCLs.

The wireless charging unit may further include a cover layer covering an uppermost surface or a lowermost surface of the double-sided FCCLs.

The cover layer may be an insulating layer made of a thermosetting material and bonded by using an adhesive.

The cover layer may be a solder resist coated and hardened layer.

According to one preferred embodiment of the present invention, there is provided a method for manufacturing a multi wireless charging apparatus, including: preparing at least two double-sided FCCLs having circuit patterns formed on an upper surface or a lower surface thereof; compressing the double-sided FCCLs by using rigid base layers therebetween, the rigid base layers being disposed in regions of a plurality of wireless charging units; forming a wiring pattern electrically connecting the circuit patterns through a first conductive via hole H1and a second conductive via hole H2passing through the compressed double-sided FCCLs and the rigid base layer, in a region of the wireless charging unit; forming cover layers covering external surfaces of the double-sided FCCLs; and mounting component devices on a region of a control unit electrically connected to the wireless charging units.

In the preparing of the double-sided FCCLs, the circuit patterns may include: coil patterns each consisting of closed loops; first ends disposed inside the coil patterns; and first electrode patterns spaced apart from the first ends and disposed outside the closed loops of the coil patterns.

In the forming of the wiring pattern, the wiring pattern may electrically connect the first ends and the first electrode patterns through the first conductive via hole H1and the second conductive via hole H2.

The compressing of the double-sided FCCLs may include: forming the plurality of rigid base layers made of a prepreg in which a glass fiber is impregnated with a thermosetting resin; disposing the rigid base layers in the regions of the wireless charging units such that the rigid base layers are spaced apart from each other at a distance corresponding to a region of each folding unit; and heat-compressing the double-sided FCCLs by using the rigid base layers therebetween.

The forming of the cover layer may include: bonding an insulating layer made of a thermosetting material by using an adhesive on the external surfaces of the double-sided FCCLs; and providing shielding films made of a conductive material and formed on an external surface of the insulating layer, in the regions of the wireless charging units, for electromagnetic field shielding.

The forming of the cover layer may include: forming a solder resist layer by coating and hardening solder resist on the external surfaces of the double-sided FCCLs; and providing shielding films made of a conductive material and formed on an external surface of the solder resist layer, in the regions of the wireless charging units, for electromagnetic field shielding.

The conductive material may be conductive paste or ferrite.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Various objects, advantages and features of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings.

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings. In the specification, in adding reference numerals to components throughout the drawings, it is to be noted that like reference numerals designate like components even though components are shown in different drawings. Further, terms used in the specification, ‘first’, ‘second’, etc., can be used to describe various components, but the components are not to be construed as being limited to the terms. The terms are only used to differentiate one component from other components. Further, when it is determined that the detailed description of the known art related to the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.FIGS. 1 and 2are a top view and a side view of a multi wireless charging apparatus according to one preferred embodiment of the present invention;FIG. 3is a top view of the multi wireless charging apparatus according to one preferred embodiment of the present invention, which is folded; andFIGS. 4 to 8are exemplary views respectively showing the use types of the multi wireless charging apparatus according to the preferred embodiment of the present invention.

A multi wireless charging apparatus100according to one preferred embodiment of the present invention, for example, as shown inFIGS. 1 and 2, includes a control unit101generally controlling a wireless charging procedure, a first wireless charging unit110electrically connected to the control unit101, a second wireless charging unit120electrically connected to the control unit101and coupled with the first wireless charging unit110by a folding unit161, a third wireless charging unit130electrically connected to the control unit101and coupled with the second wireless charging unit120by a folding unit162, a fourth wireless charging unit140electrically connected to the control unit101and coupled with the third wireless charging unit130by a folding unit163, and a fifth wireless charging unit150electrically connected to the control unit101and coupled with the fourth wireless charging unit140by a folding unit164.

Also, the multi wireless charging apparatus100according to the present invention may further include a plurality of wireless charging units electrically connected to the control unit101and coupled by a folding unit.

This multi wireless charging apparatus100includes shielding films171for electromagnetic field shielding, which are respectively formed on lower surfaces of the first to fifth wireless charging units110to150. Wireless charging receivers200and300, such as a smart phone, a mobile telecommunication terminal, and the like, which are to be charged, stand on upper surfaces of the first to fifth wireless charging units110to150, respectively.

Here, the first to fifth wireless charging units110to150overlap by folding the folding units161to164, with the result that the multi wireless charging apparatus100may be transformed in a joining state where one wireless charging surface is exposed, as shown inFIG. 3.

More specifically, in the multi wireless charging apparatus100, the first to fifth wireless charging units110to150coupled with each other by the folding units161to164have a slim thickness, and the folding units161to164are made of a material having good flexibility and have a flexible structure.

In particular, each of the folding units161to164has a void161-1therein, which passes through both lateral surfaces thereof, and thus, the folding units161to164can be easily folded up or down to provide a joining structure as shown inFIG. 3. That is, in the joining structure of the multi wireless charging apparatus100shown inFIG. 3, the folding units161to164are folded so that the first to fifth wireless charging units110to150are stacked, as shown inFIG. 4.

The multi wireless charging apparatus100in the joining state ofFIG. 4performs wireless charging with respect to one wireless charging receiver. However, the multi wireless charging apparatus100may be transformed such that two wireless charging surfaces are exposed by unfolding one folding unit161, as shown inFIG. 5. Therefore, the respective folding units161to164are unfolded, and thus, the multi wireless charging apparatus may be transformed to expose three wireless charging surfaces as shown inFIG. 6, four wireless charging surfaces as shown inFIG. 7, or five wireless charging surfaces as shown inFIG. 8.

Also, the multi wireless charging apparatus100may further include a plurality of wireless charging units coupled to the fifth wireless charging unit150by a folding unit, thereby retaining five or more wireless charging surfaces.

Therefore, the multi wireless charging apparatus100according to the present preferred embodiment can be transformed or joined so as to expose the necessary number of wireless charging surfaces, by folding or unfolding the folding units161to164according to the number of wireless charging receivers needing wireless charging.

Further, the multi wireless charging apparatus100according to the present preferred embodiment can be easily carried about in the joining state as shown inFIG. 3, by folding all the folding units161to164.

Hereinafter, an inner structure of the multi wireless charging apparatus100according to the present preferred embodiment of the present invention will be described with reference toFIGS. 9 and 10.FIG. 9is an upper perspective view of the multi wireless charging apparatus according to the preferred embodiment of the present invention, andFIG. 10is a cross sectional view taken along the line A-A′ ofFIG. 9.

As for the inner structure of the multi wireless charging apparatus100according to the present preferred embodiment, as shown inFIG. 9, the control unit101includes a plurality of circuits and devices, and the first to fifth wireless charging units110to150include coil patterns respectively connected to and extended from drivers103provided in the control unit101.

As shown inFIG. 10, which is a cross sectional view taken along the line A-A′ ofFIG. 4A, the first to fifth wireless charging units110to150of the multi wireless charging apparatus100has the same inner structure. The folding units161to164each have the void161-1, which is a separated space between the wireless charging units.

Specifically, each of the first to fifth wireless charging units110to150includes coil patterns13-1,22-1, and23-1each consisting of a plurality of continuous closed loops, which are formed on an upper surface or a lower surface of double-sided flexible copper clad laminates (FCCLs)10and20combined by each rigid base layer30therebetween; first ends13-2,22-2and23-2disposed in an inner space between the coil patterns13-1,22-1, and23-1; first electrode patterns13-3,22-3, and23-3spaced apart from the first ends13-2,22-2and23-2such that they are disposed outside the closed loops of the coil patterns13-1,22-1, and23-1; a wiring pattern41′ electrically connecting the first ends13-2,22-2and23-2to each other and the first electrode patterns13-3,22-3and23-3to each other by filling a first conductive via hole H1and a second conductive via hole H2with a conductive material; second insulating layers60provided on upper and lower surfaces by an adhesive50, as cover layers for protecting the wiring pattern41′ and other metal patterns and preventing oxidation thereof; and a shielding film171provided on a lower surface of the lower second insulating layer60.

The rigid base layer30is a prepreg in which a glass fiber is impregnated with a thermosetting resin, and has excellent strength and shear stress. Therefore, the rigid base layer30may be compressed between the double-sided flexible copper clad laminates (FCCLs)10and20, thereby to serve as a durable member supporting each of the first to fifth wireless charging units110to150. These rigid base layers30are provided in the region of the first to fifth wireless charging units110to150, and thus, the separated space, such as the void161-1, is formed between adjacent two of the rigid base layers30.

This void161-1constitutes a region of the folding unit161between the double-sided FCCLs10and20, and contributes to folding the folding units161between adjacent two of the first to fifth wireless charging units110to150.

The first and second conductive via holes H1and H2passing through the double-sided FCCLs10and20are filled with a conductive metal, with the result the wiring pattern41′ is formed across the first conductive via hole (H1) and a second conductive via hole (H2). Therefore, the wiring pattern41′ can electrically connect the first ends13-2,22-2, and23-2and the first electrode patterns13-3,22-3, and23-3, through the first conductive via hole H1and the second conductive via hole H2.

The shielding film171is made of a conductive material, such as, conductive paste, ferrite, or the like, in order to shield the coil patterns13-1,22-1, and23-1, the wiring pattern41′, and the like, from external magnetic field. In particular, the shielding film171may be formed on the lower surface of the lower second insulating layer60by using ferrite mixed with an adhesive at a region for each of the first to fifth wireless charging units110to150.

Here, the multi wireless charging apparatus100according to the present preferred embodiment employs two double-sided FCCLs10and20as an example, but is not limited thereto. A plurality of double-sided FCCLs may be used so that a plurality of circuit layers are stacked.

As such, the multi wireless charging apparatus100constituted as above may be manufactured to have a slim thickness by using the rigid base layer30and the double-sided FCCLs10and20, and the multi wireless charging apparatus100are folded by the folding units161to164, and thus, the wireless charging units may be stacked in various types as shown inFIGS. 4 to 8. In particular, in a case where wireless charging is performed while the wireless charging unit are stacked as shown inFIG. 4, the multi wireless charging apparatus100form shielding between the stacked wireless charging units by the shielding film171, thereby improving reliability in wireless charging.

Hereinafter, a method for manufacturing a multi wireless charging apparatus according to another preferred embodiment of the present invention will be described with reference toFIGS. 11 to 17.FIGS. 11 to 17are cross sectional views for illustrating the process for manufacturing a multi wireless charging apparatus according to another preferred embodiment of the present invention, as taken along the line A-A′ ofFIG. 9.

As for the method for manufacturing the multi wireless charging apparatus100according to the present embodiment, first, double sided FCCLs10and20where first copper foils12and22are laminated on upper surfaces of first insulating layers11and21made of a thermosetting material such as polyimide, and second copper foils13and23are laminated on lower surfaces of the first insulating layers11and21, as shown inFIG. 11, are prepared.

Then, as shown inFIG. 12, after preparing the double-sided FCCLs10and20, any one or both of the first copper foils12and22and the second copper foils13and23of the double-sided FCCLs10and20are used to form a predetermined circuit layer for each of the first to fifth wireless charging units110to150.

For example, the second copper foil13of the first double-sided FCCL10is used to form a first circuit layer13′ including a coil pattern13-1consisting of a plurality of continuous closed loops, a first end13-2and a first electrode pattern13-3of the coil pattern13-1.

In the same manner, the first copper foil22of the second double-sided FCCL20is used to form a second circuit layer22′ corresponding to the first circuit layer13′. The second circuit layer22′ includes a coil pattern22-1consisting of a plurality of continuous closed loops, a first end22-2and a first electrode pattern22-3of the coil pattern22-1.

Further, the first and second circuit layers13′ and22′ further include second electrode patterns (not shown), which are integrated into second ends (not shown) of the coil patterns13-1and22-1as one body, respectively. Here, a third conductive via hole (not shown) for interlayer connection between the second electrode patterns (not shown) of the first and second circuit layers may be formed.

Then, as shown inFIG. 13, the first double-sided FCCL10and the second double-sided FCCL20are disposed such that the first circuit layer13′ faces the second circuit layer22′, and rigid base layers30are disposed in the regions of the first to fifth wireless charging units110to150, between the first double-sided FCCL10and the second double-sided FCCL20.

The disposed first double-sided FCCL10and the second double-sided FCCL20are heat-compressed by using the thus disposed rigid base layers30, thereby forming a stacking structure as shown inFIG. 14.

As such, in a case where a plurality of double-sided FCCLs each having a circuit layer or circuit layers formed on one surface or both surfaces thereof are used, a coil pattern consisting of a plurality of closed loops can be easily formed. Further, the above heat compressing procedure enables the thickness of the entire part including the rigid base layer30to be slimmed.

Here, a first conductive via hole H1for interlayer connection of the first ends13-2and22-2and a second conductive via hole H2for interlayer connection of the first electrode patterns13-3and22-3, which are formed in the circuit layers13′ and22′, are formed in the double-sided FCCLs10and20. Here, the first or second conductive via hole H1or H2is a plated through hole (PTH), and formed by a mechanical drilling process such as computerized numerical control (CNC) drilling or the like.

When the first and second conductive via holes H1and H2formed by this drilling process are plated with a conductive metal, the first and second conductive via holes H1and H2become filled with the conductive metal and plating layers40covering external surfaces of the double-sided FCCLs10and20are formed, as shown inFIG. 14.

Then, the upper plating layer40and the outer copper foil12are etched, as shown inFIG. 15, thereby to form a wiring pattern41′ across from the first conductive via hole H1to the second conductive via hole H2.

Here, the lower plating layer40and the lowermost copper foil23may be etched to form a third circuit layer23′ including a coil pattern23-1, and a first end23-2and a first electrode pattern23-3of the coil pattern23-1.

Therefore, the wiring pattern41′ can electrically connect the first ends13-2,22-2, and23-2and the first electrode patterns13-3,22-3, and23-3.

Then, in order to protect the exposed circuits including the wiring pattern41′ and prevent oxidation thereof, as shown inFIG. 16, a coverlay process is performed to form second insulating layers60on the exposed surface of the upper first insulating layer11and the exposed surface of the lower first insulating layer21, including the wiring pattern41′, by using an adhesive50therebetween.

This coverlay process is performed in order to protect and insulate the uppermost exposed surface and the lowermost exposed surface of the etched double-sided FCCLs, and is applicable to fine circuits by uniformalizing heat-resistant adhesive strength, electric insulation, flame-retardant property, flex-resistant property, and adhesive flowability.

Specifically, the coverlay process may be performed by two manners, largely.

The first manner, as shown inFIG. 16, may be performed by compressing the second insulating layers60on the exposed surface of the upper first insulating layer11and the exposed surface of the lower first insulating layer21, which include the wiring pattern41′, by using the adhesive50therebetween.

Here, as a material of the second insulating layers60, a thermosetting resin such as polyimide may be used, like the upper first insulating layer11and the lower first insulating layer21. This polyimide is excellent in heat resistant property because it can be used at a temperature up to 250° C., and properties thereof are less changed from a low temperature to a high temperature. Further, the polyimide has good impact-resistant property and good dimensional stability. Further, the polyimide is excellent in electric properties, friction-resistant property, and flame-retardant property.

The second manner may be performed by coating only solder resist (SR) on the exposed surface of the upper first insulating layer11including the wiring pattern41′ and the exposed surface of the lower first insulating layer21, followed by hardening. Here, as the solder resist (SR), for example, photo resist may be used.

This solder resist (SR) is a kind of insulating permanent coating material, and may be formed in a film type covering the wiring pattern41′ so that undesired connection is prevented to occur due to soldering conducted during a subsequent procedure in which components of the control unit101are mounted.

This coverlay process may be performed by the compressing procedure while shielding films171are provided on the lower surface of the second lower insulating layer60, or a procedure of forming the shielding films171may be separately performed.

Therefore, as shown inFIG. 17, the shielding films171are formed on the lower surface of the lower second insulating layer60, correspondingly to the rigid base layers30in the regions of the first to fifth wireless charging units110to150.

The shielding film171may be formed by using a conductive material such as conductive paste, ferrite, or the like.

Then, devices (not shown) constituting the control unit101, which is connected to the first wireless charging unit110, are mounted on a region of the control unit101.

As to the method for manufacturing the multi wireless charging apparatus according to the present preferred embodiment, a coil pattern stacking structure can be easily made, the entire thickness of the multi wireless charging apparatus100can be slimmed, and the folding units161to164including the inner voids161-1can be easily formed, by using the double-sided FCCLs10and20.

Hereinafter, a function of the multi wireless charging apparatus according to the present invention thus manufactured will be described with reference toFIG. 18.FIG. 18is a block diagram for illustrating a function of the multi wireless charging apparatus according to the present invention.

The multi wireless charging apparatus100according to the present invention may be divided into a plurality of wireless charging units110,120, . . . ,1n0including first to fifth wireless charging units110to150, which are shown inFIG. 1, and a control unit101controlling the wireless power transmission of the plurality of wireless charging units110,120, . . . ,1n0.

In particular, the control unit101includes a main controller102, a plurality of drivers103respectively driving the plurality of wireless charging units110,120, . . . ,1n0in response to a control signal of the main controller102, a detector104detecting information about whether a plurality of wireless charging receivers200-1, . . . ,200-nare positioned correspondingly to the wireless charging units110,120, . . . ,1n0, and a comparator105comparing currents and voltages detected by the detector104with set values to determine whether or not the detected currents and voltages are larger than the set values.

This multi wireless charging apparatus100determines from the comparator105that the wireless charging receivers200-1, . . . ,200-nare present if current and voltage detected by the detector104are larger than the set values, and wirelessly charging the plurality of wireless charging receivers200-1, . . . ,200-npositioned correspondingly to the wires charging units110,120, . . . ,1n0at the same time.

In addition, in a case where the multi wireless charging apparatus100performs wireless charging while the wireless charging units overlap as shown inFIG. 4or5, the multi wireless charging apparatus100can perform wireless power transmission without interference by the shielding film171provided on the lower surfaces of the wireless charging units110,120, . . . ,1n0.

Therefore, the multi wireless charging apparatus according to the present invention can wirelessly charge the plurality of wireless charging receivers at the same time, and allow wireless power transmission without interference through a shielding effect by the shielding film.

In addition, since the multi wireless charging apparatus according to the present invention is slimmed through a thin thickness, and overlapped and combined in various types by using the folding units161to164, it can be conveniently carried about.

As set forth above, the multi wireless charging apparatus according to the present invention can wirelessly charge the plurality of wireless charging receivers at the same time, and allow wireless power transmission without interference through a shielding effect by the shielding film.

Further, since the multi wireless charging apparatus according to the present invention is slimmed through a thin thickness, and overlapped and combined in various types by using the folding units, it can be conveniently carried out.

Although the spirit of the present invention was described in detail with reference to the preferred embodiments, it should be understood that the preferred embodiments are provided to explain, but do not limit the spirit of the present invention.

Also, it is to be understood that various changes and modifications within the technical scope of the present invention are made by a person having ordinary skill in the art to which this invention pertains.