(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2009/0021212 A1
`HASEGAWA et al.
`(43) Pub. Date:
`Jan. 22, 2009
`
`US 20090021212A1
`
`(54) COIL UNIT AND ELECTRONIC
`INSTRUMENT
`
`(75) Inventors:
`
`Minoru HASEGAWA, Suwa-shi
`(JP); Hirofumi OKADA, Suwa-shi
`s: Yoichiro KONDO, Chino-shi
`
`Correspondence Address:
`OLIFF & BERRIDGE, PLC
`P.O. BOX 320850
`ALEXANDRIA, VA 22320-4850 (US)
`
`(73) Assignee:
`
`SEIKO EPSON
`CORPORATION, Tokyo (JP)
`
`(21) Appl. No.:
`
`12/176,072
`
`(22) Filed:
`
`Jul.18, 2008
`
`Foreign Application Priority Data
`(30)
`Jul. 20, 2007 (JP) ................................. 2007-189812
`Publication Classification
`
`(51) Int. Cl
`(2006.01)
`H02. 7/00
`(52) U.S. Cl. ........................................................ 32O/108
`(57)
`ABSTRACT
`A coil unit includes a planar coil that has a transmission side
`and a non-transmission side, a magnetic sheet provided over
`the non-transmission side of the planar coil, and a heat sink/
`magnetic shield plate stacked on a side of the magnetic sheet
`opposite to a side that faces the planar coil, the heat sink/
`magnetic shield plate dissipating heat generated by the planar
`coil and shielding magnetism by absorbing a magnetic flux
`that has not been absorbed by the magnetic sheet. The heat
`sink/magnetic shield plate has a thickness larger than that of
`the magnetic sheet.
`
`33
`
`30
`
`31
`
`32---
`
`60
`
`
`
`Ex.1005
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`Patent Application Publication
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`Jan. 22, 2009 Sheet 1 of 6
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`US 2009/0021212 A1
`
`FIG.1.
`
`
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`Ex.1005
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`Patent Application Publication
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`Jan. 22, 2009 Sheet 2 of 6
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`US 2009/0021212 A1
`
`FIG.2
`
`31
`
`32---
`
`60
`
`
`
`Ex.1005
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`Patent Application Publication
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`Jan. 22, 2009 Sheet 3 of 6
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`US 2009/0021212 A1
`
`
`
`
`
`V8” ?IGH
`
`Ex.1005
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`Patent Application Publication
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`Jan. 22, 2009 Sheet 4 of 6
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`US 2009/0021212 A1
`
`FIG.4
`
`
`
`15
`
`1
`
`4
`
`| | |
`|
`
`No..
`
`|
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`
`*(=
`
`**** • • • • • • • • • • • • • • • • | | | |-
`(O
`
`<!--
`
`100
`
`|
`
`
`
`
`
`
`
`
`
`
`
`Ex.1005
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`Patent Application Publication
`
`Jan. 22, 2009 Sheet 5 of 6
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`US 2009/0021212 A1
`
`FIG.5
`
`
`
`14
`
`6A 16B
`
`15
`
`112
`
`11
`
`O2
`
`100
`
`Ex.1005
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`Patent Application Publication
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`Jan. 22, 2009 Sheet 6 of 6
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`US 2009/0021212 A1
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`FIG.6
`
`31
`
`
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`Ex.1005
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`US 2009/0021212 A1
`
`Jan. 22, 2009
`
`COIL UNIT AND ELECTRONIC
`INSTRUMENT
`
`0001 Japanese Patent Application No. 2007-189812 filed
`on Jul. 20, 2007, is hereby incorporated by reference in its
`entirety.
`
`BACKGROUND OF THE INVENTION
`0002. The present invention relates to a coil unit utilized
`for non-contact power transmission using a coil, an electronic
`instrument, and the like.
`0003) Non-contact power transmission that utilizes elec
`tromagnetic induction to enable power transmission without
`metal-to-metal contact has been known. As application
`examples of non-contact power transmission, charging a por
`table telephone, charging a household appliance (e.g., tele
`phone handset), and the like have been proposed.
`0004. Non-contact power transmission has a problem in
`that a transmission coil generates heat. Technologies for Sup
`pressing such heat generation have been proposed. JP-A-8-
`103028 discloses a design method that suppresses heat gen
`eration during non-contact charging. JP-A-8-148360
`discloses technology that suppresses heat generation by
`adapting a suitable configuration of a coil and a magnetic
`material. JP-A-11-98.705 discloses a non-contact charging
`device provided with an air-cooling mechanism. JP-A-2003
`272938 discloses a structure in which a ceramic is disposed
`between a primary coil and a secondary coil to dissipate heat.
`JP-A-2005-110357 discloses the structure of a housing with
`an improved heat dissipation capability.
`
`SUMMARY
`0005. According to one aspect of the invention, there is
`provided a coil unit comprising:
`0006 a planar coil that has a transmission side and a non
`transmission side;
`0007 a magnetic sheet provided over the non-transmis
`sion side of the planar coil; and
`0008 aheat sink/magnetic shield plate stacked on a side of
`the magnetic sheet opposite to a side that faces the planar coil,
`the heat sink/magnetic shield plate dissipating heat generated
`by the planar coil and shielding magnetism by absorbing a
`magnetic flux that has not been absorbed by the magnetic
`sheet,
`0009 the heat sink/magnetic shield plate having a thick
`ness larger than that of the magnetic sheet.
`(0010. According to another aspect of the invention, there
`is provided a coil unit comprising:
`0011 a coil;
`0012 a magnetic material disposed near the coil; and
`(0013 a member disposed so that the magnetic material is
`placed between the coil and the member,
`(0014) the member having a thickness larger than that of the
`magnetic material.
`(0.015 According to another aspect of the invention, there
`is provided an electronic instrument comprising one of the
`above coil units.
`
`BRIEF DESCRIPTION OF THE SEVERAL
`VIEWS OF THE DRAWING
`0016 FIG. 1 is a view schematically showing a charger
`and a charging target.
`
`0017 FIG. 2 is an exploded oblique view showing a coil
`unit.
`0018 FIG. 3A is an oblique view showing a coil unit from
`the front side, and
`0019 FIG. 3B is an oblique view showing a coil unit from
`the back side.
`0020 FIG. 4 is an oblique view showing a substrate from
`the front side.
`0021 FIG. 5 is an oblique view showing a substrate from
`the back side.
`0022 FIG. 6 is a view showing a modification in which a
`temperature detection element is provided on the front side of
`a substrate.
`
`DETAILED DESCRIPTION OF THE
`EMBODIMENT
`0023 Several aspects of the invention may provide a coil
`unit that exhibits excellent heat dissipation capability and can
`be reduced in thickness, and an electronic instrument using
`the coil unit.
`0024. According to one embodiment of the invention,
`there is provided a coil unit comprising:
`0025 a planar coil that has a transmission side and a non
`transmission side;
`0026 a magnetic sheet provided over the non-transmis
`sion side of the planar coil; and
`0027 a heat sink/magnetic shield plate stacked on a side of
`the magnetic sheet opposite to a side that faces the planar coil.
`the heat sink/magnetic shield plate dissipating heat generated
`by the planar coil and shielding magnetism by absorbing a
`magnetic flux that has not been absorbed by the magnetic
`sheet,
`0028 the heat sink/magnetic shield plate having a thick
`ness larger than that of the magnetic sheet.
`0029 Heat generated by the planar coil is dissipated
`through solid heat conduction of the magnetic sheet and the
`heat sink/magnetic shield plate stacked on the planarcoil. The
`heat sink/magnetic shield plate has a function of a heat sink
`and a function of a magnetic shield that absorbs a magnetic
`flux which has not been absorbed by the magnetic sheet. As
`the material for the heat sink/magnetic shield plate, a non
`magnetic material (i.e., a generic name for a diamagnetic
`material, a paramagnetic material, and an antiferromagnetic
`material) may be used. Aluminum or copper may be suitably
`used as the material for the heat sink/magnetic shield plate.
`0030. The heat sink/magnetic shield plate is formed to
`have a thickness larger than that of the magnetic sheet. A
`magnetic flux which has not been absorbed by the magnetic
`sheet is absorbed by the heat sink/magnetic shield plate. In
`this case, the heat sink/magnetic shield plate is inductively
`heated by a magnetic flux which has not been absorbed by the
`magnetic sheet. However, since the heat sink/magnetic shield
`plate has a given thickness, the heat sink/magnetic shield
`plate has a relatively large heat capacity and a low heat gen
`eration temperature. Moreover, the heat sink/magnetic shield
`plate easily dissipates heat due to its dissipation characteris
`tics. Therefore, heat generated by the planar coil can be dis
`sipated efficiently. Moreover, the coil unit can be formed to
`have a thickness as thin as about 1.65 mm, for example.
`0031. The coil unit may further include:
`0032 a substrate, the heat sink/magnetic shield plate
`being secured on the substrate; and
`0033 a temperature detection element provided on the
`substrate, the temperature detection element detecting the
`
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`US 2009/0021212 A1
`
`Jan. 22, 2009
`
`temperature of the planar coil due to heat generation that is
`transferred through solid heat conduction of the magnetic
`sheet and the heat sink/magnetic shield plate.
`0034. This enables detection of an abnormality when the
`temperature of the heat sink/magnetic shield plate increases
`to a large extent due to an increase in temperature of the coil
`caused by insertion of a foreign object, for example.
`In the coil unit,
`0035
`0036 heat transfer conductive patterns may be formed on
`a front side and a back side of the substrate, the front side
`facing the heat sink/magnetic shield plate; and
`0037 the temperature detection element may be provided
`on the back side of the substrate.
`0038 According to this configuration, heat generated by
`the planar coil is transferred to the temperature detection
`element through solid heat conduction of the magnetic sheet,
`the heat sink/magnetic shield plate, the heat transfer conduc
`tive pattern on the front side, the substrate, and the heat
`transfer conductive pattern on the back side. Moreover, since
`the temperature detection element is provided on the back
`side of the substrate, the temperature detection element does
`not interfere with the heat sink/magnetic shield plate.
`0039. In the coil unit, the heat transfer conductive patterns
`formed on the front side and the back side of the substrate may
`be connected via a through-hole formed through the sub
`strate. The substrate is an insulator and has low heat transfer
`properties. However, the heat transfer properties can be
`improved by providing the through-hole.
`0040. In the coil unit, a depression may beformed in a side
`of the heat sink/magnetic shield plate that faces the substrate;
`and the temperature detection element may be provided on a
`front side of the substrate and disposed inside the depression
`formed in the heat sink/magnetic shield plate, the front side of
`the Substrate facing the heat sink/magnetic shield plate.
`According to this configuration, even if the temperature
`detection element is provided on the front side of the sub
`strate, the temperature detection element does not interfere
`with the heat sink/magnetic shield plate. When the planar coil
`has an air-core section at the center of the planar coil, a hole
`may be formed in the heat sink/magnetic shield plate as a
`depression at a position corresponding to the air-core section.
`According to one embodiment of the invention, since the heat
`sink/magnetic shield plate has a given thickness, the heat
`sink/magnetic shield plate can have a thickness Sufficient to
`receive the temperature detection element. When employing
`the above structure, aheat transfer conductive pattern may be
`formed on the front side of the substrate.
`In the coil unit,
`0041
`0042 the temperature detection element may be an ele
`ment that breaks or Suppresses power Supplied to the planar
`coil based on the temperature of the planar coil due to heat
`generation. This makes it possible to stop or Suppress power
`Supplied to the planarcoil when an abnormality has occurred.
`Examples of the temperature detection element include a
`thermistor of which the resistance increases at a high tem
`perature to suppress or break current, and an element (e.g.,
`fuse) that is melted at a high temperature to break current.
`0043. The coil unit may further include a covering mem
`ber that covers an edge of the magnetic sheet. The edge of the
`magnetic sheet is fragile and is easily removed. However, the
`material of the edge of the magnetic sheet can be prevented
`from being scattered by covering the edge of the magnetic
`
`sheet with the protective sheet. The covering member may be
`formed using an insulating sheet or a sealing member (e.g.,
`silicone).
`0044. In the coil unit, the covering member may be a
`protective sheet having a hole that receives the planar coil, the
`protective sheet covering edges of the magnetic sheet and the
`heat sink/magnetic shield plate and securing the magnetic
`sheet and the heat sink/magnetic shield plate on afront side of
`the Substrate. According to this configuration, the covering
`member can also be used as a member for securing the mag
`netic sheet and the heat sink/magnetic shield plate.
`0045. In one embodiment of the invention, a plurality of
`the magnetic sheets may be provided. When magnetic Satu
`ration occurs using only one magnetic sheet when a large
`current flows through the planar coil (e.g., when power is
`turned ON), a leakage flux can be reduced by providing a
`plurality of magnetic sheets. The heat sink/magnetic shield
`plate has a thickness larger than the total thickness of the
`plurality of magnetic sheets.
`0046. In the coil unit,
`0047 the planar coil may have an inner end lead line and
`an outer end lead line, the inner end lead line being provided
`over the non-transmission side of the planar coil; and
`0048 a spacer member may be disposed between the pla
`nar coil and the magnetic sheet, the spacer member having a
`thickness Substantially equal to the thickness of the inner end
`lead line.
`0049. This allows the transmission side of the planar coil
`to be made flat so that the primary coil and the secondary coil
`are easily disposed adjacently when performing non-contact
`power transmission. Although the non-transmission side of
`the planar coil protrudes due to the inner end lead line, the
`non-transmission side of the planar coil can be made flat and
`caused to adhere to the magnetic sheet by utilizing the spacer
`member. The heat transfer properties can thus be maintained.
`0050. In the coil unit,
`0051 the substrate may have a mounting surface provided
`with a mounted component in an area that extends from an
`area that faces the heat sink/magnetic shield plate, and the
`mounting Surface may be provided on the back side of the
`substrate.
`0.052 According to this configuration, since only the pla
`narcoil, the magnetic sheet, and the heat sink/magnetic shield
`plate protrude from the front side of the substrate, the primary
`coil and the secondary coil are easily disposed adjacently
`when performing non-contact power transmission.
`0053 According to another embodiment of the invention,
`there is provided a coil unit comprising:
`0054 a coil;
`0055 a magnetic material disposed near the coil; and
`0056 a member disposed so that the magnetic material is
`placed between the coil and the member,
`0057 the member having a thickness larger than that of the
`magnetic material.
`0.058 According to another embodiment of the invention,
`the magnetic sheet according to one embodiment of the
`invention may be the magnetic material, and the heat sink/
`magnetic shield plate may be the member disposed so that the
`magnetic material is placed between the coil and the member.
`In this case the member is inductively heated by a magnetic
`flux which has not been absorbed by the magnetic material.
`However, since the member thicker than the magnetic mate
`rial has a given thickness, the member has a relatively large
`
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`US 2009/0021212 A1
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`Jan. 22, 2009
`
`heat capacity and a low heat generation temperature. There
`fore, the member can dissipate heat generated by the planar
`coil without overheating.
`0059. According to another embodiment of the invention,
`there is provided an electronic instrument comprising one of
`the above coil units.
`0060 Preferred embodiments of the invention are
`described in detail below. Note that the following embodi
`ments do not in any way limit the scope of the invention
`defined by the claims laid out herein. Note that all elements of
`the following embodiments should not necessarily be taken as
`essential requirements for the invention.
`0061
`1. Charging System
`0062 FIG. 1 is a view schematically showing a charger 10
`and a charging target 20. A secondary-side electronic instru
`ment (e.g., portable telephone 20) is charged using a primary
`side electronic instrument (e.g., charger 10) by non-contact
`power transmission utilizing electromagnetic induction that
`occurs between a coil of a coil unit 12 of the charger 10 and a
`coil of a coil unit 22 of the portable telephone 20.
`0063 Opposite sides of the coil units 12 and 22 when
`performing non-contact power transmission as shown in FIG.
`1 are referred to as transmission sides. In FIG. 1, the upper
`side of the coil unit 12 is the transmission side, and the lower
`side of the coil unit 22 is the transmission side. The side
`opposite to the transmission side is referred to as a non
`transmission side.
`0064. 2. Structure of Coil Unit
`0065. The configurations of the coil units 12 and 22 are
`described below with reference to FIGS. 2, 3A, and 3B taking
`the coil unit 12 as an example. Note that the structure shown
`in FIG. 2 may also be applied to the coil unit 22.
`0066 FIG. 2 is an exploded oblique view showing the coil
`unit 12, FIG. 3A is an oblique view showing the coil unit 12
`from the front side, and FIG. 3B is an oblique view showing
`the coil unit 12 from the back side.
`0067. In FIG. 2, the coil unit 12 is basically configured to
`include a planar coil (coil) 30 that has a transmission side 31
`and a non-transmission side 32, a magnetic sheet 40 provided
`over the non-transmission side 32 of the planar coil 30, and a
`heat sink/magnetic shield plate 50 stacked on the side of the
`magnetic sheet opposite to the side that faces the planar coil
`3O.
`0068. The planar coil 30 is not particularly limited insofar
`as the planar coil 30 is a flat (planar) coil. For example, an
`air-core coil formed by winding a single-core or multi-core
`coated coil wire in a plane may be used as the planar coil 30.
`In this embodiment, the planar coil 30 has an air-core section
`33 at the center of the planar coil 30. The planar coil 30
`includes an inner end lead line 34 connected to the inner end
`of the spiral, and an outer end lead line 35 connected to the
`outer end of the spiral. In this embodiment, the inner end lead
`line 34 is provided toward the outside in the radial direction
`through the non-transmission side 32 of the planar coil 30.
`This allows the transmission side 31 of the planarcoil 30 to be
`made flat so that the primary coil and the secondary coil are
`easily disposed adjacently when performing non-contact
`power transmission.
`0069. The magnetic sheet (magnetic material) 40 disposed
`over the non-transmission side 32 of the planar coil 30 is
`formed to have a size sufficient to cover the planar coil 30. The
`magnetic sheet 40 receives a magnetic flux from the planar
`coil 30 to increase the inductance of the planar coil 30. A soft
`magnetic material is preferably used as the material for the
`
`magnetic sheet 40. A Soft magnetic ferrite material or a soft
`magnetic metal material may be used as the material for the
`magnetic sheet 40.
`0070 The heat sink/magnetic shield plate 50 is disposed
`on the side of the magnetic sheet 40 opposite to the side that
`faces the planar coil 30. The thickness of the heat sink/mag
`netic shield plate 50 is larger than that of the magnetic sheet
`40. The heat sink/magnetic shield plate 50 has a function of a
`heat sink and a function of a magnetic shield that absorbs a
`magnetic flux which has not been absorbed by the magnetic
`sheet 40. As the material for the heat sink/magnetic shield
`plate 50, a non-magnetic material (i.e., a generic name for a
`diamagnetic material, a paramagnetic material, and an anti
`ferromagnetic material) may be used. Aluminum or copper
`may be Suitably used as the material for the heat sink/mag
`netic shield plate 50.
`0071
`Heat generated by the planar coil 30 when a current
`is caused to flow through the planar coil 30 is dissipated
`utilizing Solid heat conduction of the magnetic sheet 40 and
`the heat sink/magnetic shield plate 50 stacked on the planar
`coil 30. A magnetic flux which has not been absorbed by the
`magnetic sheet 40 is absorbed by the heat sink/magnetic
`shield plate 50. In this case, the heat sink/magnetic shield
`plate 50 is inductively heated by a magnetic flux which has
`not been absorbed by the magnetic sheet 40. However, since
`the heat sink/magnetic shield plate 50 has a given thickness,
`the heat sink/magnetic shield plate 50 has a relatively large
`heat capacity and a low heat generation temperature. More
`over, the heat sink/magnetic shield plate 50 easily dissipates
`heat due to its dissipation characteristics. Therefore, heat
`generated by the planarcoil 30 can be dissipated efficiently. In
`this embodiment, the total thickness of the planar coil 30, the
`magnetic sheet 40, and the heat sink/magnetic shield plate 50
`can be reduced to about 1.65 mm, for example.
`0072. In this embodiment, a spacer member 60 having a
`thickness Substantially equal to the thickness of the inner end
`lead line 34 is provided between the planar coil 30 and the
`magnetic sheet 40. The spacer member 60 is formed in the
`shape of a circle having almost the same diameter as that of
`the planar coil 30, and has a slit 62 so as to avoid at least the
`inner end lead line 34. The spacer member 60 is a double
`sided adhesive sheet, for example. The spacer member 60
`bonds the planar coil 30 to the magnetic sheet 40.
`0073. In this embodiment, although the non-transmission
`side32 of the planarcoil 30 protrudes due to the inner end lead
`line 34, the non-transmission side 32 of the planarcoil 30 can
`be made flat and caused to adhere to the magnetic sheet 40 by
`utilizing the spacer member 60. The heat transfer properties
`can thus be maintained.
`0074. In this embodiment, the coil unit 12 includes a sub
`strate 100 on which the heat sink/magnetic shield plate 50 is
`secured. In this case, the heat sink/magnetic shield plate 50
`dissipates heat to the substrate 100. The substrate 100 has coil
`connection pads 103 connected to the inner end lead line 34
`and the outer end lead line 35 of the planar coil 30.
`(0075. The coil unit 12 includes a protective sheet 70 that
`covers the edge of the magnetic sheet 40 and the heat sink/
`magnetic shield plate 50 and secures (bonds) the magnetic
`sheet 40 and the heat sink/magnetic shield plate 50 to a
`surface 101 of the substrate 100. In this case, the inner end
`lead line 34 and the outer end lead line 35 of the planarcoil 30
`are connected to the coil connection pads 103 of the substrate
`100 to pass over the protective sheet 70 (see FIG. 3A). The
`protective sheet 70 has a hole 71 that receives the planar coil
`
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`30. The protective sheet 70 also functions as a covering mem
`ber that covers the edge of the magnetic sheet 40. The edge of
`the magnetic sheet 40 is fragile and is easily removed. How
`ever, the material of the edge of the magnetic sheet 40 can be
`prevented from being scattered by covering the edge of the
`magnetic sheet 40 with the protective sheet 70 (i.e., covering
`member). The covering member may be formed of a sealing
`member (e.g., silicone) instead of the protective sheet 70.
`0076. The coil unit 12 is produced as follows. The mag
`netic sheet 40 and the heat sink/magnetic shield plate 50 are
`stacked on the substrate 100. In this case, the substrate 100 is
`positioned on a jig (not shown) by utilizing holes 104 formed
`at the four corners of the substrate 100. Positioning pins that
`protrude from the jig are fitted into the holes 104 (e.g., four
`holes) formed in the substrate 100, holes 51 (e.g., four holes)
`formed in the heat sink/magnetic shield plate 50, and holes
`107 formed in the substrate 100 corresponding to the holes
`51. The heat sink/magnetic shield plate 50 is thus positioned
`with respect to the substrate 100 placed on the jig. The mag
`netic sheet 40 is then placed on the heat sink/magnetic shield
`plate 50, and the magnetic sheet 40 is covered with the pro
`tective sheet 70 so that the magnetic sheet 40 and the heat
`sink/magnetic shield plate 50 are secured on the substrate 100
`using the protective sheet 70.
`0077. The planar coil 30 is then secured (bonded) on the
`magnetic sheet 40 through the spacer member 60 inside the
`hole 71 formed in the protective sheet 70. The inner end lead
`line 34 and the outer end lead line 35 of the planar coil 30 are
`then connected to the coil connection terminals 103 of the
`substrate 100 to obtain the coil unit 12.
`0078. As shown in FIG. 3B, the coil unit 12 according to
`this embodiment includes a temperature detection element 80
`that is provided on a back side 102 of the substrate 100 and
`detects the temperature of the planar coil 30 due to heat
`generation that is transferred through solid heat conduction of
`the magnetic sheet 40 and the heat sink/magnetic shield plate
`50, for example. Even if a foreign object or the like has been
`inserted between the primary coil and the secondary coil so
`that the temperature of the primary-side planar coil 30 has
`increased abnormally, the abnormality can be detected by the
`temperature detection element 80. Power transmission may
`be stopped when the temperature detection element 80 has
`detected that the temperature of the planar coil 30 has
`increased abnormally. The temperature detection element 80
`is not particularly limited insofar as the temperature detection
`element 80 has a temperature detecting function. In this
`embodiment, the temperature detection element 80 is formed
`using a thermistor of which the resistance increases at a high
`temperature to Suppress or break current, for example. An
`element (e.g., fuse) that is melted at a high temperature to
`break current may be used instead ofathermistor. This makes
`it possible to break or Suppress a current that flows through
`the planar coil 30 when the temperature of the heat sink/
`magnetic shield plate has abnormally increased due to an
`increase in temperature of the planar coil 30 caused by inser
`tion of a foreign object or the like.
`007.9
`FIG. 4 is a wiring pattern diagram showing the front
`side 101 of the substrate 100, and FIG. 5 is a wiring pattern
`diagram showing the back side 102 of the substrate 100. As
`shown in FIGS. 4 and 5, heat transfer conductive patterns 110
`and 111 are formed on the frontside 101 and the back side 102
`of the substrate 100 over almost the entire area that faces the
`heat sink/magnetic shield plate 50. The heat transfer conduc
`
`tive patterns 110 and 111 on the front side 101 and the back
`side 102 of the substrate 100 are connected via a plurality of
`through-holes 112.
`0080. Thermistor wiring patterns 113A and 113B insu
`lated from the heat sink/magnetic shield plate 50 and the heat
`transfer conductive pattern 110 are formed on the front side
`101 of the Substrate 100 shown in FIG. 4. The thermistor
`wiring patterns 113 are connected to thermistor connection
`patterns 116A and 116B formed on the back side 102 of the
`substrate 100 shown in FIG. 5 via two through-holes 114 and
`115. The thermistor connection patterns 116A and 116B are
`insulated from the heat transfer conductive pattern 111.
`I0081. According to this configuration, heat generated by
`the planar coil 30 is transferred to the temperature detection
`element 80 (omitted in FIG. 5) through solid heat conduction
`of the magnetic sheet 40, the heat sink/magnetic shield plate
`50, the heat transfer conductive pattern on the front side 101
`of the substrate 100, the through-hole 112, and the heat trans
`fer conductive pattern 111 on the back side 102 of the sub
`strate 100. Moreover, since the temperature detection element
`80 is provided on the back side 102 of the substrate 100, the
`temperature detection element 80 does not interfere with the
`heat sink/magnetic shield plate 50. Note that the thermistor
`wiring patterns 113A and 113 B may be provided on the back
`side 102 of the substrate 100, and the heat transfer conductive
`pattern 110 may be formed all over the front side 111 of the
`Substrate 100.
`I0082) Note that the heat transfer conductive patterns 110
`and 111 formed on the front side 101 and the back side 102 of
`the substrate 100 may not be connected via the through-holes
`112 formed through the substrate 100. For example, when the
`thickness of the substrate 100 is sufficiently small, heat may
`be transferred through an insulating material of the Substrate
`1OO.
`0083. In this embodiment, as shown in FIG. 3B, the sub
`strate 100 has a mounting surface provided with a mounted
`component 106 in an area that extends from the area that faces
`the heat sink/magnetic shield plate 50. The mounting surface
`is provided on the back side 102 opposite to the front side 101
`that faces the heat sink/magnetic shield plate 50.
`I0084. Therefore, since only the planar coil 30, the mag
`netic sheet 40, and the heat sink/magnetic shield plate 50
`protrude from the front side 101 of the substrate 100, the
`primary coil and the secondary coil are easily disposed adja
`cently when performing non-contact power transmission.
`0085 3. Modification
`I0086 Although only some embodiments of the invention
`have been described in detail above, those skilled in the art
`would readily appreciate that many modifications are pos
`sible in the embodiments without materially departing from
`the novel teachings and advantages of the invention. Accord
`ingly, Such modifications are intended to be included within
`the scope of the invention. Any term cited with a different
`term having a broader meaning or the same meaning at least
`once in the specification and the drawings can be replaced by
`the different term in any place in the specification and the
`drawings.
`I0087. The above embodiments have been described taking
`an example relating to non-contact power transmission. Note
`that the invention may be similarly applied to non-contact
`signal transmission utilizing an electromagnetic induction
`principle. As shown in FIG. 6, the temperature detection
`element 80 may be provided on a front side 201 of a substrate
`200. In this case, aheat sink/magnetic shield plate 210 having
`
`Ex.1005
`APPLE INC. / Page 11 of 12
`
`

`

`US 2009/0021212 A1
`
`Jan. 22, 2009
`
`a hole 211 (see FIG. 6) may be used instead of the heat
`sink/magnetic shield plate 50 shown in FIG. 2. Since the hole
`211 is formed corresponding to the air-core section 33 of the
`planar coil 30, the heat sink effect does not deteriorate. Since
`the hole 211 is formed in the heat sink/magnetic shield plate
`210, the temperature detection element 80 does not interfere
`with the heat sink/magnetic shield plate 210 even if the tem
`perature detection element 80 is provided on the front side
`201 of the substrate 200. In this case, it suffices that the heat
`transfer conductive pattern (omitted in FIG. 6) be formed on
`the front side 201 of the substrate 100 in the area that faces the
`heat sink/magnetic shield plate 210. A depression may be
`formed instead of the hole 211 formed in the heat sink/mag
`netic shield plate 210 insofar as interference with the tem
`perature detection element 80 does not occur. The heat sink/
`magnetic shield plate 210 shown in FIG. 6 may be used
`instead of the heat sink/magnetic shield plate 50 shown in
`FIG 2.
`0088 A plurality of magnetic sheets 40 shown in FIGS. 2
`and 6 may be provided. When magnetic Saturation occurs
`using only one magnetic sheet 40 when a large current flows
`through the planar coil 30 (e.g., when power is turned ON), a
`leakage flux can be reduced by providing a plurality of mag
`netic sheets 40.
`0089. A planarcoil is suitable as the coil in order to reduce
`the thickness of the coil unit. Note that the invention is not
`limited thereto. A planar coil formed by winding a coil wire
`around a planar core formed using a planar magnetic material
`may also be used.
`0090 Although only some embodiments of the invention
`have been described in detail above, those skilled in the art
`would readily appreciate that many modifications are pos
`sible in the embodiments without materially departing from
`the novel teachings and advantages of the invention. Accord
`ingly, Such modifications are intended to be included within
`the scope of the invention.
`What is claimed is:
`1. A coil unit comprising:
`a planar coil t