The present invention contains subject matter related to Japanese Patent Application JP 2007-141690 filed in the Japanese Patent Office on May 29, 2007, the entire contents of which being incorporated herein by reference.
1. Field of the Invention
The present invention relates to a coil module apparatus suitably applied to a contactless power transferring coil that carries out contactless charging of a charged appliance such as a mobile phone unit, a PHS (Personal Handyphone System) telephone, a PDA (Personal Digital Assistant), a mobile game device, a digital camera apparatus, a notebook personal computer or the like. In particular, the present invention relates to a coil module apparatus which, by assembling a flat coil that has been made slim into a module, has improved resistance to bending and improved strength and can be easily installed in a charged appliance.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2006-339329 discloses a flat coil apparatus for contactless power transferring so as to obtain a sufficiently slim apparatus (see pages 7 to 8 and FIG. 1). With this flat coil apparatus, a spiral coil is formed so as to be disposed on a circuit board and a so-called return conductor formed in a direction that traverses the coil in the radial direction from the center to the outer periphery is formed by a printed circuit on the circuit board. By using a printed circuit as the return conductor, it is possible to minimize the thickness of the flat coil apparatus, and to make the entire flat coil apparatus sufficiently slim.
However, when using a slim coil such as one in the flat coil apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2006-339329, resistance to bending and strength for the flat coil apparatus may be reduced.
Further, in the flat coil apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2006-339329, the flat coil itself remains exposed. Accordingly, the process of incorporating the flat coil apparatus into a charged appliance such as a mobile appliance may be complicated.
It is desirable to provide a coil module apparatus capable of maintaining the resistance to bending and the strength of a coil that has been made slim and of being easily incorporated in an appliance.
According to an embodiment of the invention, there is provided a coil module apparatus. The coil module apparatus includes: a flat coil having a flat shape; a circuit board for the flat coil; a magnetic sheet provided so as to cover one surface portion of the flat coil; connection terminals for connecting the flat coil and the circuit board; and a case that encloses the flat coil, the circuit board, and the magnetic sheet and encloses the connection terminals so that the connection terminals are partly exposed.
According to an embodiment of the invention, the flat coil is assembled into a module by enclosing the flat coil and the like inside a case. By enclosing the flat coil inside the case, it is possible to obtain the resistance to bending and the strength of the flat coil. In addition, by assembling the flat coil into a module, the flat coil can be incorporated in a charged appliance in a simplified manner.
According to an embodiment of the invention, since the flat coil and the like are incorporated in a case and therefore the resistance to bending and the strength of the flat coil can be obtained. Also, since the flat coil is assembled into a module, the flat coil can be incorporated in a charged appliance in a simplified manner.
Embodiments of the present invention can be applied to a coil module apparatus that realizes a contactless charging function when incorporated in a mobile phone unit.
Construction of Coil Module Apparatus
The coil module apparatus further includes a circuit board 4, a temperature sensor 5, a double-sided tape sheet 6, and a magnetic sheet 7. The circuit board 4 carries out charging control during contactless charging, control over the transmission and reception of predetermined data, and the like. The temperature sensor 5 detects the temperature of the secondary side transfer coil 3 during contactless charging. The double-sided tape sheet 6 is provided so as to cover the secondary side transfer coil 3 from the opposite side to the first case piece 1. The magnetic sheet 7 is stuck onto the secondary side transfer coil 3 via the double-sided tape sheet 6 so as to cover the secondary side transfer coil 3.
The coil module apparatus further includes a double-sided tape sheet 8 and a metal sheet 9. The double-sided tape sheet 8 is stuck onto the magnetic sheet 7. The metal sheet 9 is stuck onto the secondary side transfer coil 3 via the double-sided tape sheet 8 and the magnetic sheet 7 so as to cover the secondary side transfer coil 3. That is, the magnetic sheet 7 and the metal sheet 9 are stuck in that order on the secondary side transfer coil 3 via the double-sided tape sheet 6 and the double-sided tape sheet 8, respectively.
Connection terminals 10 are provided on the second case piece 2 and when the coil module apparatus is attached to the mobile phone unit, the connection terminals 10 are connected to connection terminals provided on the mobile phone unit for the electrical continuity of the secondary side transfer coil 3, the circuit board 4, and the temperature sensor 5.
The first case piece 1 and the second case piece 2 are placed facing one another and connected to one another with the components from the secondary side transfer coil 3 to the metal sheet 9 enclosed therein and by doing so, a rectangular box-shaped coil module apparatus as shown in
Construction of the Secondary Side Transfer Coil
As shown in
The flexible printed circuit board 21 is an extremely thin sheet-like circuit board made of a material such as polyimide resin and has a surface insulating layer formed thereon. The surface insulating layer is formed on the surface excluding a first coil connecting portion 23, a second coil connecting portion 25, and a first external connection terminal portion 26, and a second external connection terminal portion 27. The first coil connecting portion 23 is located inside an inner periphery portion 22 of the flat coil when the flat coil has been stuck to the flexible printed circuit board 21. The second coil connecting portion 25 is located in a periphery outside an outer periphery portion 24 of the flat coil when the flat coil has been stuck to the flexible printed circuit board 21.
The first coil connecting portion 23 and the first external connection terminal portion 26 are electrically connected via a first internal wiring pattern 28 formed under the surface insulating layer. Similarly, the second coil connecting portion 25 and the second external connection terminal portion 27 are electrically connected via a second internal wiring pattern 29 formed under the surface insulating layer.
When the flat coil is stuck onto the flexible printed circuit board 21, a winding start portion in the inner periphery portion 22 is electrically connected to the first coil connecting portion 23 and a winding end portion of the outer periphery portion 24 is electrically connected to the second coil connecting portion 25. With this construction, the secondary side transfer coil 3 has no parts where the wire 20 overlaps itself, so that the thickness of the secondary side transfer coil 3 can be made extremely thin.
The magnetic sheet 7 and the metal sheet 9 are stuck via the double-sided tape sheet 6 and the double-sided tape sheet 8 respectively on the opposite surface of the secondary side transfer coil 3 to the surface on the first case piece 1-side. The magnetic sheet 7 and the metal sheet 9 are provided to efficiently form magnetic paths for the secondary side transfer coil 3 to increase the magnetic flux during contactless charging and also suppress unnecessary radiation due to magnetic fields produced during contactless charging.
Alternative Construction of the Secondary-Side Transfer Coil
As shown in
In this case, the secondary side transfer coil 3 includes a four-layer structure. For example, a first layer circuit board 31, a second layer circuit board 32, a third layer circuit board 33, and a fourth layer circuit board 34 are respectively formed of wiring conductive patterns 35 that have been wound in spirals on sheet-like circuit boards of a material such as polyimide resin.
A surface insulating layer 36 is formed on a surface of the first layer circuit board 31 as a topmost layer, and an adhesive layer and an insulating interlayer are formed in between the first layer circuit board 31 and the second layer circuit board 32. In the same way, an adhesive layer and an insulating interlayer are formed in between the second layer circuit board 32 and the third layer circuit board 33 and an adhesive layer and an insulating interlayer are formed in between the third layer circuit board 33 and the fourth layer circuit board 34. The magnetic sheet 7 and the metal sheet 9 are stuck onto the rear surface of the fourth layer circuit board 34 that is the bottommost layer via an adhesive layer and an insulating interlayer.
As shown in
In addition, the first through-holes 38 on the inner periphery portion 37 side of the conductive patterns 35 on each layer are electrically connected to third through-holes 41 provided on the outer periphery portion 39 side of the conductive patterns 35 on each layer.
Also, the second through-holes 40 of the fourth layer circuit board 34, for example, are electrically connected via a second internal conductive pattern 42 to a second external connecting terminal portion 44. Similarly, the first through-holes 38 of the fourth layer circuit board 34 are electrically connected via the third through-holes 41 and a first internal conductive pattern 43 to a first external connecting terminal portion 45.
When a flat coil with a multilayer structure is used as the secondary side transfer coil 3, the flat coil is formed by the conductive patterns 35 of the flexible printed circuit boards 31 to 34 on each layer, and therefore the thickness can be made even slimmer than the flat coil that uses the wire 20 described earlier.
Attachment of the Coil Module Apparatus
When attaching the coil module apparatus 50 to such a mobile phone unit, a rear cover 54 of the mobile phone unit is removed. Subsequently, before the battery pack 51 is attached, the coil module apparatus 50 is inserted into the coil module hole portion 53 provided on the rear of the display unit as shown by the dotted arrow in
Next, the battery pack 51 is attached to the battery pack attachment hole portion 52 of the mobile phone unit and then the rear cover 54 is attached. By doing so, as shown in
Note that the coil module apparatus 50 is attached to the rear surface of the display unit in this example. However, an insertion hole portion for the coil module apparatus 50 may instead be provided on a base surface portion 55 of the mobile terminal shown in
Effect of the First Embodiment
As is clear from the above description, in the coil module apparatus according to the first embodiment, the first case piece 1 and the second case piece 2 are placed facing one another and connected with the components from the secondary side transfer coil 3 to the metal sheet 9 enclosed therein to assemble a flat coil into a module. By doing so, the resistance to bending and the strength of a flat coil that has been made slim can be obtained with the first case piece 1 and the second case piece 2. Since the flat coil is provided as a module, when attached to a mobile phone unit, the coil module apparatus may only need to be inserted inside the mobile phone unit, so that the flat coil is incorporated in a simplified manner. Accordingly, the ease and productivity of the incorporating process can be improved.
Also, since a process that inserts the coil module apparatus into a charged appliance such as a mobile phone unit is sufficient as the incorporating process, it is possible to easily provide a contactless charging function to only charged appliances that may actually require such contactless charging function.
The first case piece 1 and the second case piece 2 are formed so as to enclose the components from the secondary side transfer coil 3 to the metal sheet 9 in the coil module apparatus according to the first embodiment. In contrast, a coil module apparatus according to a second embodiment is formed using a rear cover of a charged appliance, such as a mobile phone unit, as the first case piece 1 described above.
Note that parts of the coil module apparatus according to the second embodiment that are the same as those in the coil module apparatus according to the first embodiment described earlier have been assigned the same reference numerals in the drawings used to describe the coil module apparatus according to the second embodiment and duplicated description thereof is omitted.
Construction of Coil Module Apparatus According to Second Embodiment
That is, the coil module apparatus according to the second embodiment uses the rear cover 54 of the mobile phone unit in place of the first case piece 1 described above. The coil module apparatus according to the second embodiment is formed so as to enclose components from the secondary side transfer coil 3 to the metal sheet 9 in an enclosure region internally formed by placing the rear cover 54 and the second case piece 2 facing one another.
Attachment of Coil Module Apparatus According to Second Embodiment
When the coil module apparatus 60 is attached to such a mobile phone unit, after the battery pack 51 has been attached to the battery pack attachment hole portion 52, the coil module apparatus 60 is attached to the mobile phone unit by attaching the rear cover to the mobile phone unit. By doing so, as shown in
Effect of the Second Embodiment
As is clear from the above description, in the coil module apparatus according to the second embodiment, the first case piece 1 that forms the coil module apparatus is also used as the rear cover of a charged appliance such as a mobile phone unit, which makes it possible to reduce the number of components, in addition to achieving the same effect as the first embodiment described earlier.
Modifications of the embodiments described above will now be described. Note that the modifications described below may be individually or collectively applied to the coil module apparatuses of the embodiments described earlier.
First Modification
As shown in
Second Modification
As shown in
Third Modification
As shown in
Fourth Modification
As shown in
Fifth Modification
As shown in
Sixth Modification
As shown in
Seventh Modification
As shown in
Eighth Modification
As shown in
Ninth Modification
As shown in
Tenth Modification
As shown in
Eleventh Modification
As shown in
It is known that the battery pack 51 will expand somewhat due to repeated charging. With the second case piece 2 that contacts the battery pack 51 being formed of elastic resin, it will be possible to absorb the expansion of the battery pack 51.
Although the present invention has been applied to a coil module apparatus of a mobile phone unit in the embodiments described above, the present invention can be applied to a coil module apparatus for a PHS (Personal Handyphone System) telephone, a PDA (Personal Digital Assistant), a mobile game device, a digital camera apparatus, or a notebook computer. By doing so, the same effects as described above can be obtained.
The embodiments and modifications described above are mere examples of the present invention and the present invention is not limited to such embodiments and modifications. It should therefore be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.
Number | Date | Country | Kind |
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2007-141690 | May 2007 | JP | national |