COIL ANTENNA STRUCTURE AND PORTABLE ELECTRONIC APPARATUS

• US 20070052600A1
• Filed: 10/26/2006
• Published: 03/08/2007
• Est. Priority Date: 06/14/2005
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: KAMITANI, Gaku, KAWAHATA, Kazunari, MARUSAWA, Hiroshi, KONOIKE, Takehiro
• Granted Patent: US 7,466,283 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10326 the antenna being of the very-near field type, e.g. capacitive
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 7/08 Ferrite rod or like elongated core

Abstract

A coil antenna structure includes a first magnetic component extending in the thickness direction of a tabular primary casing. A second magnetic component and a third magnetic component, which are magnetically connected to the first magnetic component, are disposed on the first principal surface side and the second principal surface side of the primary casing, respectively. The first magnetic component is provided with a coil component surrounding it. In this manner, a U-shaped magnetic path is provided at an end portion of the primary casing so as to detour around a substrate defining an internal conductor. Likewise, a U-shaped magnetic path including fourth to sixth magnetic components is provided in a secondary casing defining a clamshell type casing together with the primary casing so as to detour around a substrate defining as an internal conductor.

Claims

1. A coil antenna structure comprising:

a tabular casing having a first principal surface and a second principal surface opposed thereto; and

a magnetic component and a coil component surrounding the magnetic component provided in the casing;

wherein

the magnetic component extends at least in a thickness direction of the casing and defines a magnetic path from the first principal surface side to the second principal surface side.

2. The coil antenna structure according to claim 1, wherein the magnetic component defines a first magnetic component, and a second magnetic component magnetically connected to the first magnetic component is disposed on the first principal surface side of the casing.

3. The coil antenna structure according to claim 2, wherein a third magnetic component magnetically connected to the first magnetic component is disposed on the second principal surface side of the casing.

4. The coil antenna structure according to claim 3, wherein the first, the second, and the third magnetic components comprise an integral magnetic component.

5. The coil antenna structure according to claim 4, wherein the integral magnetic component is a sheet-shaped magnetic component that is bent over the first principal surface and the second principal surface of the casing.

6. The coil antenna structure according to claim 3, wherein a plurality of groups, each comprising the first, the second, and the third magnetic components, are provided.

7. The coil antenna structure according to claim 3, wherein at least one of the second magnetic component and the third magnetic component is provided separately from the first magnetic component.

8. The coil antenna structure according to claim 7, wherein a gap is interposed between the first magnetic component and the second or third magnetic component provided separately from the first magnetic component.

9. The coil antenna structure according to claim 3, wherein cross-sectional areas of the second and the third magnetic components are greater than a cross-sectional area of the first magnetic component in a principal surface direction of the casing.

10. The coil antenna structure according to claim 9, wherein the second and the third magnetic components are substantially in the shape of one of a sheet and a film.

11. The coil antenna structure according to claim 10, wherein the first magnetic component is substantially in the shape of one of a sheet and a film.

12. The coil antenna structure according to claim 1, wherein the first magnetic component is disposed in the vicinity of an end portion of the casing.

13. The coil antenna structure according to claim 1, wherein a circuit substrate is disposed in the casing, the first magnetic component is disposed so as to penetrate the circuit substrate, and an incision portion extending in a direction farther from the first magnetic component is disposed at least in a conductor of a portion surrounding the first magnetic component of the circuit substrate.

14. The coil antenna structure according to claim 1, wherein the casing comprises an electrically conductive frame arranged to accommodate a liquid crystal display panel, and the first magnetic component is disposed outside a loop defined by the electrically conductive frame.

15. The coil antenna structure according to claim 14, wherein a constriction portion is provided on the outside of the electrically conductive frame, and the first magnetic component is disposed in the constriction portion.

16. The coil antenna structure according to claim 1, wherein a magnetic barrier component arranged to restrict passage of magnetic flux through a route different from the magnetic path including the first magnetic component is disposed in the vicinity of the first magnetic component.

17. The coil antenna structure according to claim 3, wherein a magnetic barrier component arranged to restrict passage of magnetic flux through a route different from the magnetic path including the first magnetic component is disposed on at least one of opposed surfaces of the second and the third magnetic components or in a space sandwiched by the opposed surfaces.

18. The coil antenna structure according to claim 1, wherein the casing defines a primary casing, a secondary casing for defining a clamshell structure together with the primary casing is provided, and the first magnetic component is disposed at a connection pivot portion of the primary casing for connecting the secondary casing.

19. The coil antenna structure according to claim 1, wherein the casing defines a primary casing, a secondary casing capable of being freely opened or closed relative to the primary casing is provided, and a fourth magnetic component is disposed in the secondary casing, the fourth magnetic component extending at least in the thickness direction of the secondary casing, defining a magnetic path from a first principal surface to a second principal surface of the secondary casing, and being magnetically connected to the first magnetic component while the secondary casing is closed relative to the primary casing.

20. The coil antenna structure according to claim 19, wherein a fifth magnetic component magnetically connected to the fourth magnetic component is disposed on the first principal surface side of the secondary casing, and a sixth magnetic component magnetically connected to the fourth magnetic component is disposed on the second principal surface side of the secondary casing.

21. The coil antenna structure according to claim 20, wherein the fourth, the fifth, and the sixth magnetic components comprises an integral magnetic component.

22. The coil antenna structure according to claim 21, wherein the integral magnetic component is a sheet-shaped magnetic component that is bent over the first principal surface and the second principal surface of the secondary casing.

23. The coil antenna structure according to claim 20, wherein a plurality of groups, each comprising the fourth, the fifth, and the sixth magnetic components, are provided.

24. The coil antenna structure according to claim 20, wherein at least one of the fifth magnetic component and the sixth magnetic component is provided separately from the fourth magnetic component.

25. The coil antenna structure according to claim 24, wherein a gap is interposed between the fourth magnetic component and the fifth or sixth magnetic component provided separately from the fourth magnetic component.

26. The coil antenna structure according to claim 20, wherein cross-sectional areas of the fifth and the sixth magnetic components are greater than a cross-sectional area of the fourth magnetic component in the principal surface direction of the secondary casing.

27. The coil antenna structure according to claim 26, wherein the fifth and the sixth magnetic components are substantially in the shape of one of a sheet and a film.

28. The coil antenna structure according to claim 27, wherein the fourth magnetic component is substantially in the shape of one of a sheet and a film.

29. The coil antenna structure according to claim 19, wherein the fourth magnetic component is disposed in the vicinity of an end portion of the secondary casing.

30. The coil antenna structure according to claim 19, wherein a circuit substrate is disposed in the secondary casing, the fourth magnetic component is disposed so as to penetrate the circuit substrate, and an incision portion extending in a direction farther from the fourth magnetic component is disposed at least in a conductor of a portion surrounding the fourth magnetic component of the circuit substrate.

31. The coil antenna structure according to claim 19, wherein the secondary casing comprises an electrically conductive frame arranged to accommodate a liquid crystal display panel, and the fourth magnetic component is disposed outside a loop defined by the electrically conductive frame.

32. The coil antenna structure according to claim 31, wherein a constriction portion is provided on the outside of the electrically conductive frame, and the fourth magnetic component is disposed in the constriction portion.

33. The coil antenna structure according to claim 19, wherein a magnetic barrier component for restricting passage of magnetic flux through a route different from the magnetic path including the fourth magnetic component is disposed in the vicinity of the fourth magnetic component.

34. The coil antenna structure according to claim 20, wherein a magnetic barrier component for restricting passage of magnetic flux through a route different from the magnetic path including the fourth magnetic component is disposed on at least one of opposed surfaces of the fifth and sixth magnetic components or in a space sandwiched by the opposed surfaces.

35. The coil antenna structure according to claim 1, wherein the casing comprises an electrically conductive frame arranged to accommodate a liquid crystal display panel, the frame surrounding the magnetic path, and a nonconductive portion is provided as a portion of the electrically conductive frame.

38. A portable electronic apparatus comprising the coil antenna structure according to claim 1.

36. A coil antenna structure comprising:

a magnetic component disposed such that a magnetic flux is passed so as to detour around or penetrate a region having a relatively low magnetic permeability; and

a coil component surrounding the magnetic component.

37. The coil antenna structure according to claim 36, wherein the magnetic component defines a first magnetic component, a second magnetic component magnetically connected to the first magnetic component is disposed on at least one end side of the first magnetic component, and a cross-sectional area of the second magnetic component is greater than a cross-sectional area of the first magnetic component in a direction that is substantially perpendicular to an extension direction of the first magnetic component.

39. A portable electronic apparatus comprising the coil antenna structure according to claim 36.