1111111111111111 IIIIII IIIII 11111 1111111111 1111111111 lllll 111111111111111 1111111111 11111111
`(19) United States
`
`
`(12) Patent Application Publication
`(10) Pub. No.: US 2004/0119576 Al
`
`Jun. 24, 2004
`Nakao et al.
`( 43) Pub. Date:
`
`US 20040119576Al
`
`(54) NONCONTACT COUPLER
`
`
`
`(52) U.S. Cl. .............................................................. 336/225
`
`ABSTRACT
`
`
`
`(21) Appl. No.: 10/467,871
`
`Feb. 14, 2002
`(22) PCT Filed:
`
`
`PCT/JP02/01257
`
`(86) PCT No.:
`
`(76) Inventors: Fumiaki Nakao, Tokyo (JP); Yoshio
`
`
`
`Matsuo, Tokyo (JP); Mikio Kitaoka,
`(57)
`
`Tokyo (JP); Katsuo Yamada, Tokyo
`(JP); Hiroshi Sakamoto, Tokyo (JP)
`A noncontact coupler comprising a pair of magnetic cores 1,
`
`
`
`
`
`
`Correspondence Address:
`
`1 each having a U-shaped open magnetic path, a primary
`HARNESS, DICKEY & PIERCE, P.L.C.
`
`
`coil Ll and secondary coil L2 being wound around said
`P.O. BOX 828
`
`
`
`
`cores 1, 1 separately respectively, said coupler transmitting
`BLOOMFIELD HILLS, MI 48303 (US)
`
`
`
`
`AC electric power between said primary and secondary coils
`
`
`Ll, L2 by means of an annular closed magnetic path B
`
`
`
`formed by opposing in proximity both open magnetic face
`
`
`
`sides of said cores, wherein said primary and secondary
`
`
`magnetic cores 1, 1 are respectively split at least at their
`
`
`sides facing to each other, and a gap forming a spatial
`
`
`magnetic path is interposed between said split pieces. A
`
`
`
`diameter a of a medium leg 51 positioned inside an annular
`
`groove 52 around in which the coils Ll, L2 are wound
`Feb. 14, 2001
`
`(JP) ......................................... 2001-37489
`
`
`(housed) is set almost equal to a width b of the annular
`Jul. 10, 2001
`
`(JP) ...................................... 2001-209347
`
`
`
`groove 52. These provide effects of lightening a noncontact
`
`
`
`coupler while securing its performance and improving
`
`
`
`
`
`handle ability with enhancing tolerance for positioning of the
`
`
`primary and secondary cores.
`
`(30) Foreign Application Priority Data
`
`Publication Classification
`
`(51) Int. CI.7 ..................................................... H0lF 27/28
`
`L2
`
`,
`
`1 B
`
`B
`
`3
`
`3
`
`L 1
`,
`
`3
`
`A-A CROSS-SECTION
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 001
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 1 of 17
`
`US 2004/0119576 Al
`
`\
`
`FIG. 1B
`. 1 B L 1, �2
`2 /
`
`1 A
`
`��'
`.
`3
`
`3/
`
`.
`
`3
`
`FIG. 1A
`
`I
`
`,
`
`, ... ... -, -
`
`·-­
`
`A
`
`, ----.... :-----
`
`" "
`, .... __ _
`Ll, L2
`
`A-A CROSS-SECTION
`
`,c
`
`PLAN VIEW
`
`FIG. 1D
`
`L2
`
`d
`
`Fl G.
`
`1 C
`
`,
`
`1 B
`
`Li
`
`,
`
`A-A CROSS-SECTION
`
`3
`
`3
`
`1A
`
`1B
`
`1C
`
`·L�
`
`EQUIVALENT CIRCUIT
`
`FIG. 1E
`
`L 2
`
`d � �
`
`�L1
`.
`.
`
`,
`
`EQUIVALENT CIRCUIT
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 002
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 2 of 17
`
`US 2004/0119576 Al
`
`FIG. - 2
`
`........
`
`SPILIT-TYPE CORE
`(PRESENT INVENTION)
`
`SOLID INTEGRAL ST�UCTURE
`CORE (CONVENTIONAL)
`
`-·· . ....
`.. ......... .
`·····. .. ..
`
`0
`
`+
`
`- LATERAL DISPLACEMENT (mm) -
`
`LU
`c..)
`:z
`<
`..... c..) ::>
`C
`z
`I
`LL
`_,J
`L,LJ
`Cl)
`
`w
`c..)
`z
`< l­
`e..) ::>
`C
`z
`
`_. <
`::,
`
`:::E
`
`I­:::,
`
`1-z
`
`
`w
`0
`
`LL
`LL
`
`L,LJ 0
`0
`0
`z
`
`_. CL
`::::,
`0
`0
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 003
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 3 of 17
`
`US 2004/0119576 Al
`
`FIG. 3A
`
`, C
`
`---
`
`, B
`
`B
`
`L2
`'
`
`--- ......
`----
`
`I
`
`-----I
`----\
`
`L 1
`
`, C
`
`,
`
`, A
`
`, B
`
`FIG. 3B
`
`1 C
`
`1 A
`
`1 B
`
`L2
`,
`
`----I
`----
`
`--
`
`I
`
`--
`
`I
`
`--
`--
`
`--
`
`B
`
`L 1
`
`--- ---
`
`1 C ,
`
`1 B
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 004
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 4 of 17
`
`US 2004/0119576 Al
`
`FIG. 4A
`
`1 A
`1 A
`
`UPPER CORE 1 1A
`,, 1 UPPER CORE
`'.
`',
`'.,, •. 1 LOWER CORE
`,,
`,- ....
`' , ,
`-
`,
`, ..
`,1 C
`1 C
`
`FIG. 4B
`1 A
`
`,
`
`,
`
`
`
`1 LOWER CORE
`
`I I I
`
`<, ..... __
`':----�
`1 B
`
`1 C
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 005
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 5 of 17
`
`US 2004/0119576 Al
`
`FIG. SA
`
`L 1, L2
`
`1
`
`2 :
`I
`I
`I
`
`'
`
`I
`
`- � I A
`I I i
`A
`'
`t
`----,.E=_ -;=_ ==ll===SE:::::::::::...::i-3---+-
`
`1 1
`
`I
`
`1 1
`
`I
`
`- - -
`
`PLAN VIEW
`
`FIG. 58
`
`3
`
`A-A CROSS SECTION
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 006
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 6 of 17
`
`US 2004/0119576 Al
`
`FIG. 6
`
`le
`I
`
`A ----»Nl�E - C --.;a,-.,.lc1---
`'
`.
`! 2 !
`
`B
`
`►I
`I
`
`I I
`
`, ,
`
`3
`
`3
`
`t 1 : average thickness along A
`2: average thickness along B
`t
`t 3: average thickness along C
`
`t1XA=t2XB
`
`t 1 = t 2
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 007
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 7 of 17
`
`US 2004/0119576 Al
`
`FIG. 7A
`
`, 3
`
`, 4 �
`a
`
`7B
`FIG.
`
`1 2
`
`PLAN VIEW
`
`14._,,.,4
`······ ... _ _.,
`
`FIG. 7C 1
`
`I
`
`·
`
`·-·---
`
`1 2
`
`I
`
`, 3
`
`L2
`
`A-A CROSS SECTION
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 008
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 8 of 17
`
`US 2004/0119576 Al
`
`FIG. BA
`
`4
`
`1 3 ,-
`
`j-:_ 1�
`
`a 2
`
`B 1 2
`
`a 5
`
`a4 ,.
`
`I
`
`FIG. BB
`
`SPLIT-STRUCTURE CORE
`(PRESENT INVENTION)
`
`•••••••••• , SOLID INTEGRAL
`STRUCTURE CORE
`(CONVENT ONAL)
`
`• I
`
`�--··········
`
`I
`I
`
`I
`
`I
`
`I
`
`.1
`
`1
`
`::c
`.,_ <
`a..
`0
`
`.,_ w
`
`z:
`
`..............
`= <
`:E
`
`I
`
`LL.
`0
`<
`w
`a::
`<
`
`...J
`<
`z:
`0
`
`.,_
`0
`w
`IV)
`I
`IV)
`IV)
`0
`a::
`0
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 009
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 9 of 17
`
`US 2004/0119576 Al
`
`FIG. 9A
`
`4,
`
`EXAMPLE 1
`
`, 4
`
`1-----J__ ______ -J,
`3
`
`3
`
`PERSPECTIVE VIEW
`
`4
`
`.
`
`FIG. 9B
`
`, 4
`
`EXAMPLE 2
`
`42
`
`LATERAL CROSS-SECTIONAL VIEW _
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 010
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 10 of 17
`
`US 2004/0119576 Al
`
`FIG. 10A
`
`'
`I
`I
`t __
`-� - -- - - - - - - - _r'\ - - - - - - -:- - - t- -·
`I \
`""C.J
`
`I
`'
`
`f
`
`-
`
`--- ... ""'•
`
`I
`'·
`
`Ll, L2 ..
`
`..
`
`I
`'
`
`.. ..
`
`PLAN VIEW
`
`FIG. 108
`
`,
`
`A-A·CROSS-SECTIONAL VIEW
`
`L 2
`I
`
`' �
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 011
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 11 of 17
`
`US 2004/0119576 Al
`
`FIG. 11A
`
`3
`
`L 2
`
`2
`
`2
`
`L 1
`
`3
`
`3
`
`3
`
`,
`
`___
`
`L1
`
`-"
`
`3
`
`FIG. 11 B
`
`_,
`
`3
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 012
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 12 of 17
`
`US 2004/0119576 Al
`
`FIG. 12A
`5 1
`
`5 2
`
`53
`
`53
`
`FIG. 128
`
`5,
`
`(a= b)
`
`CUTAWAY PERSPECTIVE VIEW
`
`(a= b)
`
`PLAN VIEW
`
`-FIG. 12C
`
`FIG. 12D
`
`CROSS SECTION
`
`POWER RECEIVING
`CIRCUIT
`
`POWER SUPPLYING
`CIRCUIT
`
`EQUIVALENT CIRCUIT
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 013
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 13 of 17
`
`US 2004/0119576 Al
`
`FIG. 13
`
`A :
`
`PRESENT I NVENT I ON
`
`
`B: PRESENT INVENTION
`
`C. :
`
`CONVENTIONAL
`
`0
`INCREASE-
`
`-INCREASE
`
`displacement
`
`A: a=b
`B: a=b±20%
`C: a>b+2 0%
`
`C,
`z:
`...J
`c..
`:::>
`
`0
`
`I­LU
`
`
`:z
`C,
`< ::E
`u...
`0
`
`1-:z
`
`
`LLJ
`0
`u...
`u...
`LU
`0
`0
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 014
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 14 of 17
`
`US 2004/0119576 Al
`
`FIG. 14
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 015
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 15 of 17
`
`US 2004/0119576 Al
`
`FIG. 15A
`
`1 A
`
`53
`
`FIG. -158
`
`, 8
`
`L 1, L2
`
`............. ,c
`
`5 2'
`( 5 2 )
`
`3
`
`,
`
`A-A CROSS SECTION
`
`FIG. 15D
`
`PLAN VIEW
`
`FIG. 15C
`
`.
`
`-
`
`A-A CROSS SECTION
`
`3
`
`3
`
`1 A
`
`1 B
`
`1 C
`
`L2
`
`EQUIVALENT CIRCUIT
`
`v
`
`FIG. 15E
`
`��::
`
`,
`
`EQUIVALENT CIRCUIT
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 016
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 16 of 17
`
`US 2004/0119576 Al
`
`5 3
`
`5 2 5 1
`
`FIG. 16A
`
`FIG. 168
`
`53
`
`L2
`
`CUTAWAY PERSPECTIVE VIEW
`
`FIG. 16C
`
`L 2
`
`•
`
`1
`
`L 1
`
`, .
`
`CROSS-SECTIONAL VIEW
`
`b
`
`(a> b)
`
`b
`
`PLAN VIEW
`
`FIG. 160
`
`
`
`�ECEIVING CIRCUI
`
`POWER SUPPLYING
`CIRCUIT
`
`EQUIVALENT CIRCUIT
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 017
`
`

`

`Patent Application Publication Jun. 24, 2004 Sheet 17 of 17
`
`US 2004/0119576 Al
`
`FIG. 17A
`
`L2
`
`UPPER CORE 1 '
`
`LOWER CORE 1 '
`
`l
`A ·
`
`52
`
`5,
`
`LOWER CORE 1 '
`
`53
`
`
`
`h : LATERAL O I SPLACEMENT
`
`VIEWED AT A-A
`
`Fl G. 17B
`
`c.:i -
`
`-
`
`0 +h
`- LATERAL
`
`
`DI SPLAGEMENT (mm) --+
`
`-h
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 018
`
`

`

`US 2004/0119576 Al
`
`Jun.24,2004
`
`1
`
`NONCONTACT COUPLER
`
`FIELD OF THE INVENTION
`
`[0001] This invention relates to a noncontact coupler using
`magnetic coupling technique. For example, this invention is
`useful to supply power to or charge an electronic apparatus
`such as an electric car without contacting.
`
`BACKGROUND ART
`
`[0002] A noncontact coupler using magnetic coupling
`technique is used as a means of supplying power to or
`charging an electric car, electric bicycle or other electric
`apparatuses.
`
`[0003] FIGS. 16A-16D illustrate a structure of a prior art
`noncontact coupler. In this figure, FIG. 16A is a perspective
`view of a magnetic core l', FIG. 16B is a plan view of FIG.
`16A; FIG. 16C is a cross-sectional view of a noncontact
`coupler using the core l'; and FIG. 16D is an equivalent
`circuit of the same.
`
`[0004] As shown in the figures, the noncontact coupler
`includes a pair of magnetic cores l', l', each of which
`forming a U-shaped open magnetic path, and a primary coil
`Ll and a secondary coil L2 separately wound around the
`respective cores. The cores l', l' are opposed to each other
`with both open magnetic face sides of the respective cores
`l', l' in proximity to form an annular closed magnetic path
`B to allow the primary coil and the secondary coil to
`transmit AC power (high frequency power) to each other.
`
`In this case, the core l' in which the primary coil Ll
`[0005]
`is wound corresponds to a primary of a transformer and the
`core l' in which the secondary coil L2 is wound corresponds
`to a secondary of a transformer respectively. The primary
`and the secondary are closely located each other at the
`interval of d and work as though it constituted one trans­
`former.
`
`[0006] The magnetic core l', l' is made of for example a
`ferrite magnetic body and integrally formed in a disc-shape.
`At one side of said disc magnetic core l', a circular groove
`52 is formed so that the coil Ll, L2 is wound (received)
`therein, and the U-shaped open magnetic path is formed as
`detouring around the circular groove 52. Inside the annular
`groove 52, namely in the center of the disc, is formed a
`medium leg 51 which forms one pole face of the U-shaped
`open magnetic path. On the other hand, an outer circumfer­
`ence of the annular groove 52, namely outside of the disc, is
`formed an annular outer leg 53 and the other pole face of the
`U-shaped open magnetic path.
`
`In the above noncontact transmission coupler, it is
`[0007]
`necessary to strengthen the magnetic coupling between the
`primary coil and the secondary coil for improving efficiency
`of power transmission. In other words, it is necessary to keep
`the magnetic coupling coefficient between the primary/
`secondary as high as possible. Then, in the prior art, a
`magnetic coupling was maximized between the cores l', l'
`by means of enlarging the area of the pole face (pole area)
`as large as possible. Because the wider the area of magnetic
`surface facing to each other is made, the tighter the magnetic
`coupling becomes. Therefore, the cores l', l' are formed in
`a solid integral structure, namely filled structure, having no
`void as a whole and to have a large magnetic pole area as
`
`large as possible. See Japanese Patent Application Laid­
`open Publication No. 2000-150273.
`
`In the noncontact coupler, there were some prob­
`[0008]
`lems as to its characteristics and structure stated below.
`
`[0009] Namely, the structure confining the magnetic path
`B into the magnetic cores l', l' each having a filled integral
`structure can get high coefficient of the magnet coupling
`when both the magnetic cores l', l' are faced to each other
`concentrically. However, as shown in FIGS. 17A, 17B,
`when a lateral displacement (side displacement) arises
`between both the magnetic cores l', l', then the coupling
`coefficient fairly decrease by the lateral displacement h.
`Convenience in handling of the noncontact coupler will be
`deteriorated when the changing rate of the coupling coeffi­
`cient for the displacement is large, because positioning
`between the primary and secondary requires accuracy.
`
`[0010] Further, most weight of the noncontact coupler
`owes the magnetic cores (1', l') of solid integral structure,
`increase in weight was unavoidable and this interrupted
`attempt to lighten the noncontact coupler.
`
`[0011] The first object of the present invention is to
`improve usability of the noncontact coupler while securing
`its performance.
`
`[0012] The second object of the present invention is to
`improve usability of the noncontact coupler by means of
`lightening the weight while securing its performance.
`
`[0013] The third object of the present invention is to
`improve usability of the noncontact coupler by broadening
`tolerance in positioning of the primary and secondary cores.
`
`[0014] Other objects and features according to the inven­
`tion described above would be made clear by the following
`description of the specification and drawings.
`
`DISCLOSURE OF THE INVENTION
`
`[0015] The present invention discloses following tech­
`niques in order to accomplish the above stated objects.
`
`[0016] The first main technique of the invention lies in a
`noncontact coupler comprising a pair of magnetic cores each
`having a U-shaped open magnetic path, a primary coil and
`secondary coil being wound around said cores separately
`respectively, said coupler transmitting AC electric power
`between said primary and secondary coils by means of an
`annular closed magnetic path formed by opposing in prox­
`imity both open magnetic face sides of said cores, wherein
`said primary and secondary magnetic cores are respectively
`split at least at their sides facing to each other, and a gap
`forming a spatial magnetic path (a magnetic path formed in
`a space) is interposed between said split pieces.
`
`[0017] According to the above technique, a magnetic
`coupling between the primary coil and the secondly coil is
`established not only on a tip of each split core but also in a
`wide area extending over the side surface thereof. Namely,
`opposing surface area of the primary and secondary cores is
`substantially increased, and a magnetic circuit in a direction
`perpendicular to an original magnetic path ( a winding direc­
`tion of the coil) is to be shut off. Therefore, even if both the
`cores are displaced each other laterally, the magnetic cou­
`pling between the primary coil and the secondary coil can be
`maintained. At the same time, a total weight of the core is
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 019
`
`

`

`US 2004/0119576 Al
`
`Jun.24,2004
`
`2
`
`lightened by splitting the core. This can achieve both of the
`objects in lightening the noncontact coupler while securing
`its performance and improving handleability with enhanced
`tolerance for the primary and secondary core positioning.
`
`[0018] Moreover, in the above technique, following
`aspects are efficient.
`
`[0019] Namely, each of the primary and the secondary
`magnetic cores may be formed with a plurality of core
`members and the gaps may be interposed between the
`respective core members. The primary and the secondary
`magnetic cores may be formed with fan-shaped core mem­
`bers respectively, and fan-shaped gaps having the same
`shape as the respective core members can be interposed
`between each of the core members. The primary and the
`secondary magnetic cores may be formed with a plurality of
`elongated core members arranged radially to form a circle.
`The elongated core members may be board-shaped with
`entire uniform thickness. These embodiments are efficient
`for improvement in productivity and reducing weight. It is
`also effective for improvement in uniformity and stability of
`characteristics by means of optimizing the conditions of
`forming and burning for pressure forming and burning the
`core members.
`
`[0020] The primary and the secondary magnetic core may
`be formed with the core members of the same odd number
`arranged radially to form a circle at equiangular intervals,
`the primary and the secondary core members are arranged to
`be superposed on the gaps between the opposed core mem­
`bers, so that in this state, magnetic couple between the
`primary coil and the secondary coil is formed. By means of
`the arrangement, decrease of the coefficient of the magnet
`coupling for a lateral displacement in a particular direction
`is further relieved.
`
`[0021] The second main technique of the invention is a
`noncontact coupler comprising a pair of magnetic cores each
`having a U-shaped open magnetic path, a primary coil and
`secondary coil being wound around said cores separately
`respectively, said coupler transmitting AC electric power
`between said primary and secondary coils by means of an
`annular closed magnetic path formed by opposing in prox­
`imity both open magnetic face sides of said cores, wherein
`said primary and secondary magnetic cores are respectively
`formed with annular outer circumferential core members,
`disc-shaped inner circumferential core members, and a num­
`ber of intermediate core members arranged radially to form
`a circle as connecting both said core members.
`
`[0022] According to the technique, the invention enables
`to lighten the core while decreasing a variation of a cross
`section in a direction of a magnetic path. Namely, the present
`invention improves a balance in a magnetic path and
`decreases a core loss. Further, in the above technique,
`following embodiments are effective for example.
`
`[0023] Namely, an inner circumferential edge of each of
`the intermediate cores may be tapered. An outer circumfer­
`ential edge of the intermediate core members may be
`broadened in the width. Both of these embodiments can
`achieve reducing a weight of the core and optimize a balance
`of a magnetic path.
`
`secondary coil being wound around said cores separately
`respectively, said coupler transmitting AC electric power
`between said primary and secondary coils by means of an
`annular closed magnetic path formed by opposing in prox­
`imity both open magnetic face sides of said cores, wherein
`a non-opposing corner of each of said primary and second­
`ary magnetic core is beveled.
`
`In the above technique, by means of removing a
`[0025]
`part of the core where magnetic flux density is low, it has
`become possible to lighten the core namely, to lighten the
`noncontact coupler, and to decrease a core loss by improving
`a balance of a magnetic path.
`
`[0026] The fourth main technique of the invention is a
`noncontact transmit coupler comprising a pair of disc­
`shaped magnetic cores each having an annular groove for
`winding a coil on one side, said magnetic cores being faced
`to each other at the surfaces of said annular groove in order
`to transmit electric power from a coil of one core to a coil
`of the other core by means of magnetic coupling, wherein a
`diameter of a medium leg positioned inside the annular
`groove is set almost equal to a width of said annular groove.
`
`[0027] The techniques enable to improve handleability
`with enhancing tolerance for the primary and secondary core
`positioning. In this case, preferably, difference between the
`width of the annular groove and the diameter of the medium
`leg will be within ±20%.
`
`[0028] Moreover, in the above techniques, the core loss is
`minimized because of an appropriate balance of a magnetic
`path when an area of a pole face formed with the medium leg
`and an area of a pole face formed with the annular outer leg
`positioned outside the annular groove are made generally
`equal to each other. In this case, difference between the area
`of the pole face formed with the medium leg and the area of
`the pole face formed with the outer leg may be preferably
`within ±20%.
`
`[0029] The magnetic core may be of a disc-shaped inte­
`gral-type, or may be formed with a plurality of the split cores
`in order to form a disc shape as a whole. Further, in the case
`of the magnetic core is formed in order to form a disc shape
`as a whole, fan-shaped gaps can be positioned between the
`respective split cores. These fan-shaped gaps enable to
`reduce a weight of the core and to achieve an effect to keep
`a magnetic coupling coefficient high when the displacement
`exists.
`
`[0030] The magnetic cores can be made of ferrite mag­
`netic material. The weight of the core can be decreased by
`beveling the non-opposed corners of the primary and the
`secondary magnetic cores, and risk of suffering damage at a
`peripheral end of the core can be reduced. Further, this
`embodiment is effective to lighten the noncontact coupler
`and reduce the core loss by improving a magnetic path
`balance.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0031] FIGS. lA-lE show various aspects of a noncontact
`coupler according to the first embodiment of the present
`invention.
`
`[0024] The third main technique of the invention is a
`noncontact coupler comprising a pair of magnetic cores each
`having a U-shaped open magnetic path, a primary coil and
`
`[0032] FIG. 2 is a graph which shows variation of a
`coupling coefficient for a lateral displacement with respect
`to the noncontact coupler shown in FIGS. lA-lE.
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 020
`
`

`

`US 2004/0119576 Al
`
`Jun.24,2004
`
`3
`
`[0033] FIGS. 3A-3B show schematic views of a state of
`the spatial magnetic path in the noncontact coupler shown in
`FIGS. lA-lE.
`
`[0034] FIGS. 4A and 4B show examples of arrangement
`of the core members in the noncontact coupler shown in
`FIGS. lA-lE.
`
`[0035] FIGS. 5A-5B show a plan view and a cross­
`sectional view of the second embodiment in the present
`invention respectively.
`
`[0036] FIG. 6 is a perspective view of a part of the
`magnetic core shown in FIGS. SA and 5B.
`
`[0037] FIGS. 7 A-7C show a perspective view, a plan view,
`and a cross-sectional view of the third embodiment of the
`noncontact coupler in the present invention respectively.
`
`[0038] FIGS. SA and 8B are analytical views illustrating
`a state of a cross-sectional area of the magnetic path of the
`core shown in FIG. 7.
`
`[0039] FIGS. 9A-9B respectively show a perspective view
`and a cross-sectional view of an embodiment of the inter­
`mediate core member constituting a part of the core shown
`in FIGS. 7A-7C.
`
`[0040] FIGS. lOA-lOB are a perspective view and a
`cross-sectional view of the fourth embodiment of the non­
`contact coupler in the present invention respectively.
`
`[0041] FIGS. llA and 11B show a cross-sectional view
`and a cutaway perspective view of the fifth embodiment of
`the noncontact coupler in the present invention respectively.
`
`[0042] FIGS. 12A-12D show a group of various views
`illustrating the sixth embodiment of the noncontact coupler
`in the present invention.
`
`[0043] FIG. 13 is a characteristic curve showing a state of
`variation of a magnetic coupling coefficient for a displace­
`ment of the core in relation to FIGS. 12A-12D.
`
`[0044] FIG. 14 is a cross-sectional schematic view show­
`ing a state of magnetic coupling in relation to FIGS. 12A-
`12D where a displacement of the cores exists.
`
`[0045] FIGS. 15A-15E show a group of various views of
`the seventh embodiment of the noncontact transmit coupler
`in the present invention.
`
`[0046] FIGS. 16A-16D show a group of various views of
`the structure of a conventional noncontact transmit coupler.
`
`[0047] FIGS. 17A and 17B show a graph illustrating a
`state where a lateral displacement exists in a conventional
`noncontact transmit coupler.
`
`BEST MODE FOR CARRYING OUT THE
`INVENTION
`
`[0048]
`
`(First embodiment)
`
`[0049] FIGS. lA-lC show the first embodiment of the
`noncontact coupler in the present invention.
`
`[0050] As shown in the figures, in the noncontact coupler
`according to the first embodiment, the primary and the
`secondary magnetic cores 1, 1 are formed with fan-shaped
`core members lA, lB, and lC, each of which having a
`central angle of 45°, and fan-shaped gaps, each of which
`being the same shape as the core member (g=75°), are
`
`interposed between each of the core members lA, lB, and
`lC. The core members lA, lB, and lC have U-shaped
`grooves 2 on one sides to form U-shaped open magnetic
`paths.
`
`[0051] The primary core members lA, lB, and lC and the
`secondary core members lA, lB, and lC are opposed in
`proximity at their open magnetic path sides so as to form
`annular closed magnetic paths B to allow the primary coil Ll
`and the secondary coil L2 to transmit AC power (high
`frequency power) to each other as a noncontact coupler.
`
`In this case, the respective pairs of the primary and
`[0052]
`secondary core members lA-lA, lB-lB, and lC-lC are
`magnetically coupled, and form an equivalent circuit to a
`transformer as shown in FIG. 1D or FIG. lE.
`
`In this way, the noncontact coupler wherein at least
`[0053]
`the parts facing to each other of the primary and the
`secondary magnetic cores 1, 1 are split, and the gap g for
`forming a spatial magnetic path (a magnetic path formed in
`space) is interposed between the split parts, is formed. The
`noncontact coupler loses as much weight as the fan-shaped
`gap (g=75°).
`
`[0054] The non-opposing corner of the each core member
`lA, lB, and lC is beveled beforehand. The symbol 3 shows
`the beveled portions. These beveled portions enable the core
`1, 1 to be further lightened and make it less possible to be
`damaged at the peripheral edge of the non-opposing corner.
`
`[0055] Usually, a core member is made of a ferrite mag­
`netic body produced by pressure forming and burning, and
`the ferrite magnetic body is generally brittle, so that easily
`damaged in manufacturing, conveying, or assembling pro­
`cess at the peripheral edges thereof. However the bevels 3
`are effective to prevent the damage. Further, there are
`difficulties in manufacture for a large sized ferrite core, such
`as to pressure uniformly in a pressure forming process, and
`to be vulnerable to cracking in a burning process. These
`problems are solved by forming the core as divided dis­
`closed above.
`
`[0056] FIG. 2 shows a change in characteristic for a lateral
`displacement of the noncontact coupler shown in FIG. 1.
`
`In the figure, solid lines show characteristic curves
`[0057]
`for the noncontact coupler according to the present invention
`shown in FIG. 1, on the other hand broken lines show
`characteristic curves of the conventional noncontact coupler
`shown in FIGS. 16, 17 respectably. As shown in the figure,
`compared to the conventional noncontact coupler, a self­
`inductance and a mutual-inductance for the coils Ll, L2 of
`the noncontact coupler shown in FIG. 1 have become low
`respectively as a whole, while reduction rate of the induc­
`tance when the position of the primary and the secondary
`cores is displaced in a lateral direction has significantly
`decreased. And the coupling coefficient between the primary
`coil Ll and the secondary coil L2 is not so changed
`compared to the prior ones on the average, however it has
`been clear that change for the lateral displacement ( a dis­
`placement in a lateral direction) is substantially reduced.
`
`[0058] FIG. 3 schematically shows a state of spatial
`magnetic path when the lateral displacement h arises in the
`noncontact coupler shown in FIG. 1. As shown in the figure,
`where each primary and secondary magnetic core 1, 1 is
`split, the magnetic coupling between the primary core 1 and
`
`Momentum Dynamics Corporation
`Exhibit 1007
`Page 021
`
`

`

`US 2004/0119576 Al
`
`Jun.24,2004
`
`4
`
`the secondary core 1 is established, not only at the tip
`surfaces of the split core members lA, lB, and lC, but also
`in a wide range extending over both the tip surfaces and the
`side surfaces. Accordingly, effective facing areas between
`the primary and secondary cores 1, 1 are enlarged and the
`effective facing surfaces are maintained in the case of the
`lateral displacement h, and it is prevented that a magnetic
`circuit perpendicular to preferable magnetic paths (in a
`winding direction of the coil) from forming. Inconsequence,
`even if the lateral displacement occurs between both cores,
`the primary and the secondary magnetic connection can be
`maintained. At the same time, a total weight of the core can
`be lightened because of the split cores.
`
`[0059] These steps provide effects of lightening the non­
`contact coupler while securing its performance and improv­
`ing handleability with allowances for the primary and the
`secondary core positioning.
`
`[0060] FIG. 4-A and FIG. 4-B show an example of
`arrangement of the noncontact coupler using the magnetic
`cores 1, 1 shown in FIG. 1. In the figure, any of the primary
`and the secondary magnetic cores 1, 1 is formed with the
`core members lA, lB, lC of the same odd-number (3 in this
`case), arranged radially at predetermined angular intervals
`so as to form a circle. In this case, there are two ways of
`arrangements for the core members lA, lB, and lC, forming
`the primary core (upper core 1) and the core members lA,
`lB, and lC, forming the secondary core (lower core 1) as
`shown in FIG. 4-A or FIG. 4-B.
`
`[0061] Namely, in the arrangement shown in FIG. 4-A,
`the core members lA, lB, and lC, forming the upper core
`1 and the core members lA, lB, and lC, forming the lower
`core 1 are arranged to be piled up each other, and, in this
`state, the noncontact coupler magnetically coupled with the
`primary coil and the secondary coil is formed.
`
`[0062] And, the arrangement shown in FIG. 4-B the core
`members lA, lB, and lC, forming upper core 1 and the core
`members lA, lB, and lC, forming lower core 1 are arranged
`corresponding to the gaps between the opposing core mem­
`bers. In this arrangement, the noncontact coupler is formed
`by a magnetic coupling between the primary coil and the
`secondary coil.
`
`[0063] Here, in the configuration of FIG. 4B, it is possible
`to decrease a reduction rate of the opposing surface area
`when the upper and lower cores 1, 1 are displaced in the
`direction of an arrow (h), thus to further relieve a reduction
`rate of the coupling coefficient for the lateral displacement.
`Therefore, in the use for large lateral displacement in the
`direction of the arrow (h) is expected, the non contact
`coupler may preferably be formed according to the arrange­
`ment shown in FIG. 4-B.
`
`[0064]
`
`(Second embodiment)
`
`[0065] FIG. 5 shows the second embodiment in the
`present invention. Paying attention to the difference from the
`first embodiment, the noncontact coupler of the second
`embodiment is formed with a plurality of long rectangular
`core members 1, 1, as shown in the FIG. 5-A and FIG. 5-B,
`wherein the primary and the secondary magnetic cores are
`arranged radially to form a circle.
`
`[0066] Each long rectangular core member 11 is formed
`into a plate shape having a uniform thickness as a whole
`
`(sections A, B, C as shown in FIG. 6 (tl=t2=t3). The core
`member 11 shaped like this is effective for uniform pressure
`forming. Therefore, uniformity and stability of properties of
`the core members can be improved by means of optimizing
`the conditions in forming and burning. Moreover, each of
`the core members 11 provides a U-shaped open magnetic
`path, and equalizing the areas (tlxA, t2xB) of the U-shaped
`open magnetic path at the both end surfaces (tlxA=t2xB)
`enable to optimize the magnetic path balance in the core
`members 11 and to decrease a core loss.
`
`[0067]
`
`(Third embodiment)
`
`[0068] FIG. 7 shows the third embodiment of the non­
`contact coupler in the present invention. In this embodiment,
`the noncontact coupler employs the magnetic cores 1 as
`assembled as shown in FIG. 7-B, FIG. 7-C, using three
`kinds of core members 12, 13, 14 as shown in FIG. 7-A.
`This magnetic core 1 are formed from outer circumferential
`core members 12, disc-shaped inner circumferential core
`members 13, and a number of intermediate core members 14
`arranged radially to form a circle connecting both of the core
`members 12, 13. This arrangement enables to decrease a
`variation in a cross section in the direction of the magnetic
`path, namely, to improving the balance of magnetic path and
`to reduce the core loss while the weight of the core 1 is
`reduced.
`
`[0069] FIG. 8 shows analysis of a cross section of the
`magnetic path in the core 1 shown in