TW200843278A - Coil unit and electronic instrument - Google Patents

Abstract

A coil unit (22) includes a planar air-core coil (30b) that has an air-core section, a printed circuit board (60) that is disposed on a transmission side of the planar air-core coil (30b), and a magnetic sheet (40b) that is disposed on a non-transmission side of the planar air-core coil (30b) opposite to the transmission side. The planar air-core coil (30b) includes a lead line (32) connected to an inner end of the planar air-core coil (30b) over the transmission side, and the printed circuit board (60) includes a receiving section (60a) that receives the lead line (32).

Description

200843278 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a detachable electronic device or the like using a coil. - Coil unit for force transmission [Prior Art] It is known that there is no contact power transmission using electromagnetic induction even without gold ::: transmission. As this is not connected: electricity =

:Sub-machine) Two t: Proposal for charging of mobile phones and charging of household devices (such as sub-machines of telephones). In the power transmission using electromagnetic induction, the offset on the coaxial line of the coil has a great influence on its transport s. Therefore, it is important to be placed in a suitable position by the charger. As a stipulation of the stipulations of Feng Xianghu, the current technology, there are proposals disclosed in Patent Documents 1 to 3. Patent Document 1 discloses a technique for preventing foreign matter from being inserted between a charger and a charger, and ensuring charging at an appropriate position. Patent Document 2 discloses a technique in which a hollow solenoid coil is fitted to a convex core and electromagnetically coupled. Patent Document 3 discloses a technique in which a magnetic core of a primary side is inserted into a hollow portion of a secondary side coil to perform electromagnetic coupling between one and two times. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. The core is placed on the coil. SUMMARY OF THE INVENTION 128676.doc 200843278 [Problems to be Solved by the Invention] A number of aspects of Shuming are used to provide a thin coil and improve the transmission efficiency of the coil 70 and an electronic machine using the same. [Technical means for solving the problem] The present invention is characterized in that: a green κι @ - a ring 7L is characterized by: a planar hollow coil having a hollow portion, an ancient envelope e, a °p, a wiring printed substrate The system is disposed in the planar hollow core coil for transmission, and the V-face side and the magnetic sheet are disposed in front of the front.

The front-end air-core coil is known as 3 IA >, and the transmission is: a non-transmission surface having the opposite side of the 3⁄4 surface; and the planar hollow-core coil is provided with the wiring for drawing the wiring from the side of the transmission surface (4), a line; the wiring printed circuit board is provided with an accommodating portion for accommodating the lead wire. The lead wire at the inner end of the coil increases the thickness of the planar hollow coil. However, since the lead wire is housed in the accommodating portion of the wiring printed circuit board, the thickness of the lead wire portion can be prevented from contributing to the thickness of the coil unit (planar air-core coil + magnetic sheet + wiring printed circuit board). In one aspect of the invention, the wiring printed substrate may be provided with a through hole that faces the hollow portion of the planar hollow coil. When the through hole is provided in the wiring printed circuit board, the positioning protrusion can be provided in advance in the frame in which the coil unit is housed, and the positioning protrusion protrudes into the hollow portion of the planar hollow coil through the through hole, and the coil unit is positioned in the frame. . In this case, the diameter of the through hole of the printed circuit board is smaller than the diameter of the hollow portion of the planar hollow coil, and the surface of the printed circuit board and the planar hollow coil are overlapped and surrounded by the through hole. A temperature detecting portion may be provided on the inner side of the periphery of the hollow portion. In place of this, a temperature detecting portion is provided on a surface of the wiring printed circuit board opposite to the surface of the planar air-core coil and the peripheral edge of the through hole. In either case, the temperature detecting portion can be provided in the vicinity of the hollow portion of the planar hollow coil, so that the temperature of the foreign matter when the foreign matter is mixed between the electronic device and the charger can be reliably determined, and the temperature can be raised to a specific value or higher. In case of abnormality, the countermeasures such as energization are blocked. Another aspect of the invention defines an electronic machine including a housing for housing the coil unit. In this case, the frame of the electronic device may include a coil positioning protrusion formed on an inner surface thereof, and the bellet hole of the printed circuit board protrudes into the hollow portion of the planar air-core coil, and the foregoing Positioning the planar hollow coil. In another aspect of the present invention, a coil unit includes: a planar hollow coil having a hollow portion; and a magnetic sheet disposed on a side opposite to the conveying surface of the planar hollow coil; And a printed circuit board disposed on the magnetic sheet opposite to the surface of the magnetic sheet and the flat hollow coil; wherein the planar hollow coil is provided with a coil leading from the side facing the magnetic sheet The inner end wiring is used for the outlet line; and the wiring printed circuit board is provided with the accommodating portion for accommodating the lead wire via the magnetic sheet. In this case, it is also possible to prevent the thickness of the lead portion from contributing to the thickness of the coil unit (planar air-core coil + magnetic sheet + wiring printed substrate), and it is possible to reduce the thickness. In the electronic device including the coil unit, since the planar printed circuit board is not provided between the planar hollow coil I28676.doc 200843278 and the casing of the electronic device, the through hole is not provided in the printed circuit board. The coil positioning protrusion provided in the casing of the electronic device can be protruded into the planar air-core coil to position the coil unit to the frame. Further, since the planar hollow coil is in contact with the inner surface of the casing, the distance from the coil unit on the other side is shortened, and the transmission efficiency can be improved. Still another aspect of the present invention, the coil unit may integrally include a coil housing frame as a part of the housing of the charger or the electronic device. A coil unit according to still another aspect of the present invention includes: a planar hollow coil having a hollow portion; a coil housing frame disposed on a side of a conveying surface of the planar hollow coil; and a wiring printed substrate; The wiring printed circuit board is disposed on the non-transmission surface side of the planar air-core coil; the planar printed circuit board is fixed to the coil housing frame, and the planar air-core coil is housed in the coil housing frame and the wiring printed circuit board. In the planar air-core coil, a lead wire for wiring the inner end of the coil is provided on the side of the transfer surface, and a housing portion for accommodating the lead wire is provided in the coil housing frame. In this way, it is possible to provide a rigid body structure in which the flat hollow coil is sandwiched between the coil housing frame and the wiring printed substrate before the electronic device and the charger are loaded into the housing, and the mountability of the coil is improved. Further, it is possible to prevent the thickness of the lead wire portion from contributing to the thickness of the coil unit, and to reduce the thickness. In particular, in this configuration, it is possible to prevent the winding of the coil from being loosened or the coil from being deformed during the transporting and winding operation, and it is possible to prevent deformation of the coil which adversely affects electrical characteristics such as inductance. In this configuration, a positioning projection of the above-mentioned flat 128676.doc 200843278-shaped air-core coil can be provided in the coil housing frame. Further, the step further includes: a magnetic sheet which is disposed on the non-transport surface (4) of the planar hollow coil. For example, the planar hollow coil and the magnetic sheet may be housed between the coil housing frame and the cloth: brush substrate. In the electronic device including the coil unit, the outer surface of the coil housing frame may be flush with the outer surface of the casing of the electronic device.

In other words, the coil housing frame is made to be part of the housing of the electronic device, and the surface placed on the charger is made flat. In the casing of the electronic device described above, a positioned portion positioned to the charger can be formed. Thereby, the positioning of the electronic device and the charger can be performed to improve the transmission efficiency. σ '

The structure for absorbing the thickness of the above-mentioned lead wire is also suitable for charging

A coil unit according to still another aspect of the present invention includes: a planar hollow coil having a hollow portion; a wiring printed substrate disposed on a side of a conveying surface of the planar hollow coil; and a magnetic sheet Arranging on the non-transporting surface side of the planar air-core coil; the planar hollow-core coil 'on the transmission surface side 1 has a lead for drawing out the wiring from the planar hollow coil (4): in the cloth (four) board, The accommodating portion for accommodating the lead wire is provided. The coil unit of the present invention is characterized in that it comprises: a planar hollow coil having a hollow portion; the magnetic sheet is disposed on a non-transporting surface side of the planar hollow coil, and the m-plane and the planar hollow线128676.doc -10- 200843278 lap superimposed; and a printed circuit board disposed on the second surface of the magnetic sheet; and the planar hollow coil is provided on the non-transport surface side from the foregoing A lead wire for wiring the inner end of the planar hollow coil; and the wiring printed circuit board is provided with a housing portion for accommodating the lead wire. In the coil unit of these two aspects, the same effect and effect as the coil unit of one of the present invention can be exhibited. A coil unit of a coil unit according to still another aspect of the present invention includes: a planar air-core coil having a hollow portion; and a coil housing frame disposed on a transmission surface side of the planar air-core coil; and wiring The printed circuit board is disposed on the non-transmission surface side of the planar air-core coil; the wiring printed circuit board is fixed to the coil housing frame; and the planar air-core coil is housed in the coil housing frame and the wiring printing In the planar air-core coil, a lead wire for guiding the inner end of the planar air-core coil is provided on the side of the transport surface; and the lead-out frame is provided in the coil-receiving frame The accommodating department. Further, in the coil unit of the present aspect, the coil unit of still another dimension of the present invention can exhibit the same effect and effect as the coil unit in which the coil housing frame includes the housing portion. Still another aspect of the present invention is an electronic machine system defined as a coil unit containing the same. [Embodiment] Hereinafter, a suitable embodiment of the present invention will be described in detail. In addition, the present embodiment described below should not unduly limit the content of the present invention described in the claims, and all of the configurations described in the present embodiment are not necessarily 128676.doc • 11-200843278 as a solution of the present invention. Means must be. 1. Charging System Figs. 1 and 2 are diagrams schematically showing a charging system including a charger 1 and an electronic device such as a mobile phone 2 充电 charged by the charger 1 。. Figure i shows a mobile phone with a charge of 10A and a mobile phone 2 〇A. The charging of the mobile phone 20A by charging 10A utilizes the electromagnetic induction between the coil of the coil unit 12 of the charger 1A and the coil of the coil unit 22 of the mobile phone 2A, and is not connected. Point power transmission and implementation. In the mobile phone 20A, the positioning concave portion (in the broadest sense, the clamped portion) 24 (see FIG. 3), which is not shown in FIG. 1, is positioned by the positioning projection of the charger i〇A (in the broad sense, the positioning portion) 14 Positioned and installed. By positioning the mobile phone 20A in the charger 10A in this manner, the mobile phone 20A can be attached to the charger 10A at an appropriate position, and the transmission efficiency can be improved. Here, as shown in Fig. 1, the opposing surface side when the coil units 12 and 22 are opposed to each other and the contactless power transmission is performed is referred to as a transmission surface. The coil on the upper side of the unit 12 is a conveying surface, and the lower surface of the coil unit 22 is a non-transporting surface on the side opposite to the conveying surface. 2. The structure of the coil unit 2·1. The coil unit at the inner end of the coil is the coil unit on the side of the transmission surface. The coil unit 22, which is suitable for the thin type of the mobile phone 2, is taken as an example. 12, 22. 2 is a perspective view of the coil unit 22. Fig. 3 (Α) and Fig. 3 are sectional views of the two kinds of coil units 22 which are not shown along the line VII-VII of Fig. 2, respectively. Fig. 4 and Fig. 5 are diagrams showing the coil unit shown in Fig. 3 (Α) and Fig. 3 (Β) for disintegrating the stereo 128676.doc • 12- 200843278. In the coil element 2 2, the planar hollow coil 30B and the magnetic sheet are sequentially disposed on the side opposite to the frame 20a side of the wiring printed substrate (for example, the slidable wiring substrate) 60 via the double-sided tape 7 40B and leakage flux preventing member 5〇. As shown in Figs. 4 and 5, the planar air-core coil 3'b is provided with a lead wire 32 for leading the inner end thereof from the side of the transport surface. Further, the lead wire 34 is taken out from the outer end of the planar air-core coil 30B. The double-sided tape 70 and the printed circuit board 60 disposed on the line _ ring surface side of the lead-out lead 32 are notched, and the accommodating portions 60a and 70a accommodating the lead-out line 32 are provided. The accommodating portions 60a and 70a are formed, for example, by long holes. As shown in FIG. 6, when viewed from the side of the wiring printed circuit board 6, the lead wire 32 is housed in a state of being housed in the accommodating portion 60a. As described above, when the lead wires 32 are housed in the accommodating portions 6a and 70a, the lead wires 32 can be prevented from contributing to the thickness of the coil unit 22 itself or the contribution to the thickness thereof. Further, as shown in Figs. 4 and 5, the wiring board 60 is provided with a through hole 60b at a position facing the hollow portion 31B of the planar hollow coil 30B. The diameter of the through hole 60b is set to be smaller than the diameter of the hollow portion 3 1B of the planar hollow coil 3〇B. And 'on the side of the printed circuit board 6 〇 facing the planar air-core coil 30B (examples of FIGS. 3(A) and 4) or the opposite side thereof (examples of FIGS. 3(B) and 5) • and the hollow portion 31B On the inner side, for example, a temperature detecting unit-80 such as a thermistor is provided. As described above, when the temperature detecting portion 8 is provided inside the hollow portion 31B, the temperature of the foreign matter entering between the charger 10 and the mobile phone 20 can be detected. In particular, foreign matter entering the vicinity of the hollow portion 3 1B having a large magnetic flux density is heated by the eddy current, so that the temperature of the foreign matter can be reliably detected. As shown in Fig. 3 (A) and Fig. 3 (B), the side of the magnetic sheet 40B can be covered by the leakage preventing member 128676.doc -13 - 200843278. Thereby, it is possible to prevent the magnetic powder from scattering due to the magnetic sheet 4〇B being rotted or the magnetic sheet being defective. Further, the magnetic piece 40B of the mobile phone 20 can be set to be larger than the planar hollow coil 30A of the charger 1A. Thereby, eddy current loss of the metal of the rechargeable battery and the circuit board located inside the coil unit 22 can be prevented, and the power transmission efficiency can be improved. 2.2. A coil unit having a lead wire at the inner end of the coil as a non-transmission surface side Fig. 7 is an exploded perspective view showing a second configuration example. This configuration example is an example in which the lead wires 32 from the inner ends of the planar hollow coils 3 are provided on the non-transporting surface side opposite to the transport surface side (frame side). As shown in Fig. 7, on the non-transporting surface side (lower side in Fig. 7) opposite to the conveying surface side of the planar air-core coil 30B, a magnetic sheet 4?B is provided via a double-sided tape 72. Below the magnetic sheet 4A, a wiring printed substrate 64 is provided. That is, the surface on which the magnetic sheet 40B overlaps the planar hollow coil 30B is referred to as a first surface. The wiring printed substrate 64 is superposed on the second surface of the magnetic sheet 40B. In the wiring printed circuit board 64, a housing portion (beacon hole or recess) 64a is provided at a position corresponding to the lead line 32. When the accommodating portion 64a is provided in this manner, the thickness portion formed by the lead wire 32 can be absorbed by the accommodating portion 64a via the deformation of the magnetic piece 4B, and in the structure of Fig. 7, the conveying surface of the planar hollow coil 3〇 Since the surface of the frame of the surface of the surface of the coil unit I] and the coil of the human coil unit 22 is shorter than that of the previous example, the transfer rate can be expected. Further, the planar hollow coil 30 can be positioned in the frame 128676.doc -14-200843278 by simply projecting the projections protruding from the inner surface of the frame of the mobile phone 2 into the hollow portion of the planar hollow coil 3〇. Therefore, in the case of the wiring printed substrate, the through holes for positioning are not required. 2·3·Coil unit having a coil housing frame FIGS. 8 and 9 are, for example, a frame including a mobile phone 2A shown in FIG. 1, and a part of the coil unit serving as a coil housing frame is viewed from different angles. It is an exploded perspective view. The coil housing frame is a part of the outer casing of the charger 10 or the electronic device 2, and the outer surface of the outer casing is flush with the outer surface of the coil housing_frame. Further, the configuration example shown in Figs. 8 and 9 is an example in which the lead wire 32 from the planar air-core coil 3〇b is provided on the transmission surface side (frame side). Instead of this, the lead wire 3 2 from the inner end of the planar air-core coil 30B may be provided on the non-transmission surface side (magnetic sheet side). As shown in Figs. 8 and 9, a planar hollow coil 3〇b, a magnetic piece 40B, and a single-sided tape 74 are provided between the coil housing frame 20a and the wiring printed board '66'. However, in the present embodiment, the magnetic sheet 4〇b is not essential. The coil housing frame 20a is provided with a housing portion 20b for receiving the lead wire 32 from the inner end of the planar hollow coil 3b, and a housing portion 32b for receiving the lead wire 34 from the outer end of the planar hollow coil 3b. Part 20c. Further, the coil inner end lead wire 32 is further drawn to the side opposite to the transfer surface and connected to the wiring printed substrate ^ 66 °, and Fig. 1 to Fig. 13 schematically show the manufacturing steps of the coil unit. As shown in Fig. 10, the inside of the annular rib 20d of the coil housing frame 20a is accommodated in the planar air-core coil 30B. This positioning is performed by the positioning protrusions 28 for the coil provided in the coil housing frame 20a. Next, as shown in FIG. 11, the magnetic sheet 40B is attached so as to overlap the planar hollow coil 30B. As shown in Fig. 12, the single-sided tape 74 is used as a cover to prevent the soft magnetic metal powder from falling off from the outer end of the magnetic piece 40B to the substrate provided thereunder. Next, as shown in Fig. 13, the substrate 66 is attached. Thereafter, the material (magnetic soft metal powder) of the magnetic sheet is prevented from leaking from the accommodating portions 2b, 20c provided in the casing 2A, and the accommodating portions 20b and 20c are closed by a molding material. In particular, in this configuration, compared with the coil unit of FIGS. 2 to 7, the winding of the coil can be prevented from being loosened or the coil can be deformed during the loading and winding operation, and the electrical characteristics such as inductance can be prevented. Deformation of the coil of adverse effects. Further, the structure of FIG. 2 to FIG. 13 can also be applied to the coil unit 12 of the charger 1 [Application example of the electronic device] This embodiment can be applied to all electronic devices that perform power transmission and signal transmission, for example, It can be applied to rechargeable batteries with secondary batteries, such as wristwatches, electric toothbrushes, electric razors, wireless phones, personal mobile phones, portable personal computers, PDAs (Pers〇nal Digital Assistants; personal digital assistants), electric vehicles, etc. And charging machine. Further, as described above, the present embodiment has been described in detail, and various modifications can be readily made by those skilled in the art without departing from the scope of the invention. Therefore, such modifications are all included in the scope of the present invention. For example, in a patent specification or schema, a term that is recited at least once in a different term from a broader or synonymous term may also be substituted for the different term in any part of the patent specification or schema. This embodiment relates to contactless power transmission, but the same applies to 128676.doc -16- 200843278 for contactless power transmission using the principle of electromagnetic induction. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing a type of mobile phone having a charger and a traverse. Brother 1 Implementation Fig. 2 is a perspective view of a coil unit. 3(A) and 3(B) are schematic cross-sectional views showing a cross section of the coil unit taken along line Vn-vn of Fig. 22.

Fig. 4 is an exploded perspective view of the coil unit. Fig. 5 is an exploded perspective view showing another example of the coil unit. Fig. 6 is a view showing the relationship between the accommodating portion and the lead wire of the printed circuit board. Fig. 7 is an exploded perspective view showing still another example of the coil unit. Fig. 8 is an exploded perspective view showing a coil unit having a coil housing frame. Figure 9 is an exploded perspective view of the coil unit shown in Figure 8 as viewed from another angle. Fig. 10 is a view schematically showing the steps of the coil unit shown in Fig. 8. Fig. 11 is a view schematically showing a second step of the coil unit shown in Fig. 8. Fig. 12 is a view schematically showing a third step of the coil unit shown in Fig. 8. Fig. 13 is a view schematically showing the fourth step of the coil unit shown in Fig. 8. [Main component symbol description] 10, 10A charger 10a frame 12 coil unit 128676.doc •17- 200843278

14 Positioning part (positioning protrusion) 20, 20A Electronic equipment (mobile phone) 20 a Frame 22 Coil unit 28 Coil positioning protrusions 30, 30A, 30B Planar air-core coil 30a Hollow part 32 Coil inner end lead wire 34 Coil Outer end lead wires 40A, 40B Magnetic sheet 50 Leakage flux preventing member 60 Wiring printed circuit board 62a Housing portion 62b Through hole 64 Wiring printed circuit board 64a Housing portion 66 Substrate 70 Double-sided tape 70a Housing portion 72 Double-sided tape 74 Single-sided tape Tape 80 temperature detection unit 128676.doc _ 18 _

Claims (1)

200843278 X. Patent application scope: 1. A coil unit, comprising: a planar hollow coil having a hollow portion; a wiring printed substrate disposed on a side of a conveying surface of the planar hollow coil; and a magnetic a sheet disposed on the non-transport surface of the planar air-core coil opposite to the transport surface; wherein the planar air-core coil is provided with a lead wire for routing the inner end of the transport surface side; The line printed circuit board is provided with a housing portion for housing the lead wire. 2. The coil unit of claim 1, wherein the wiring printed substrate is provided with a through hole that faces the hollow portion of the planar air-core coil. 3. The coil unit of claim 2, wherein a diameter of the through hole of the wiring printed substrate is smaller than a diameter of the hollow portion of the planar hollow coil; and the wiring printed substrate and the planar hollow coil are not described The surface of the joint is provided with a temperature detecting portion on the inner side of the periphery of the hollow portion. 4. The coil unit according to claim 1 or 2, wherein a temperature detecting portion is provided on a surface of the opposite side of the surface on which the wiring printed substrate and the planar hollow coil are overlapped, and at a peripheral edge of the through hole. A coil unit comprising: a planar hollow coil having a hollow portion; and a magnetic sheet disposed on a side opposite to the conveying surface of the planar hollow coil; and a cloth a printed circuit board disposed on the magnetic sheet opposite to a surface on which the magnetic sheet is ablated with the planar hollow coil; wherein the planar hollow coil is provided with an inner end of the coil from a side facing the magnetic sheet a lead wire for wiring; wherein the wiring printed circuit board is provided with an accommodating portion that accommodates the lead wire via the magnetic piece. a coil unit comprising: a planar air-core coil having a hollow portion; a coil housing frame disposed on a side of a transmission surface of the planar air-core coil; and a wiring printed circuit board disposed on the wiring substrate a non-transporting surface side of the planar air-core coil; the wiring printed circuit board is fixed to the coil housing frame, and the planar hollow-core coil is housed between the coil housing frame and the wiring printed circuit board; In the planar air-core coil, a lead wire for wiring the inner end of the coil is provided on the side of the transfer surface; and the coil housing frame is provided with a housing portion for accommodating the lead wire. 7. The coil unit of claim 6, wherein 128676.doc 200843278 is provided with a positioning projection for positioning the planar hollow coil in the coil housing frame. 8. The coil unit of claim 6 or 7, further comprising: a magnetic sheet disposed on the non-transmission side of the planar air-core coil; > in the coil housing frame and the wiring Between the printed boards, a uranium-like planar hollow coil and the magnetic sheet are housed. • an electronic device that is characterized in that it comprises an electronic device that houses a frame of a coil unit as claimed in any one of the claims; the frame system of the electronic device includes a coil positioning protrusion formed in the frame The inner surface of the body protrudes into the hollow portion of the planar hollow coil via the through hole of the wiring printed substrate, and the planar hollow coil is positioned. An electronic machine characterized by comprising an electronic device housing a frame of a coil unit of claim 5; • the frame system of the electronic device comprising a coil positioning protrusion formed on an inner surface of the frame 'Expanding into the aforementioned hollow portion of the planar hollow coil, and positioning the aforementioned planar hollow coil. An electronic device characterized by comprising an electronic device of the coil unit according to any one of claims 6 to 8; wherein, the outer surface of the coil housing frame and the outer surface of the frame of the electronic device For the same plane. The electronic device according to any one of claims 9 to 11, wherein in the frame of the electronic device, a portion that is positioned at the charger is formed by the 128676.doc 200843278. 13. A coil unit, comprising: a planar hollow coil having a hollow portion; a wiring printed substrate disposed on a side of the transfer surface of the planar hollow coil; and a magnetic sheet disposed on the magnetic sheet a non-transporting surface side of the planar hollow coil; a surface | in the planar hollow coil, a lead wire for drawing a wire from the inner end of the planar hollow coil is provided on the side of the conveying surface; The line printed circuit board is provided with a housing portion for housing the lead wire. A coil unit, comprising: a planar hollow coil having a hollow portion; the magnetic sheet being disposed on a non-transport surface of the planar hollow coil and having a first surface and the planar hollow coil And a wiring printed circuit board disposed on the second surface of the magnetic sheet; and the planar hollow core coil is provided with an inner end of the planar hollow coil on the side of the non-transport surface a lead wire for wiring; 'the wiring printed circuit board is provided with a housing portion for accommodating the lead wire. A coil unit comprising: a planar hollow coil having a hollow portion; a coil receiving frame disposed on a side of the conveying surface of the planar hollow coil; and 128676.doc 200843278 wiring printed substrate, The wiring printed circuit board is fixed to the non-transmission surface side of the planar air-core coil; the wiring printed circuit board is fixed to the coil housing frame; and the planar air-core coil is housed between the coil housing frame and the wiring printed circuit board In the planar air-core coil, a lead wire for guiding the inner end of the planar air-core coil is provided on the side of the transfer surface; and the coil housing frame is provided with a housing portion for accommodating the lead wire . 16. An electronic machine characterized by comprising a coil unit as claimed in any one of claims 13 to 15. 128676.doc