Multiaxial antenna chip

• US 20040061660A1
• Filed: 06/26/2003
• Published: 04/01/2004
• Est. Priority Date: 06/27/2002
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Tokai RIKA Denki Seisakusho
• Original Assignee: Kabushiki Kaisha Tokai RIKA Denki Seisakusho
• Inventors: Yoshida, Yutaka, Okada, Hirofumi, Hiramitsu, Takayuki, Kimura, Akihito
• Granted Patent: US 7,068,223 B2
• Time in Patent Office: Days
• US Class Current: 343/788
• CPC Class Codes: E05B 19/0082 Keys or shanks being removably stored in a larger object, e.g. a remote control or a key fob general constructional details of electronic keys G07C9/00944
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: G07C 9/00944 Details of construction or manufacture
• CPC Class Codes: H01Q 1/3208 characterised by the application wherein the antenna is used
• CPC Class Codes: H01Q 1/3241 particular used in keyless entry systems
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 7/06 with core of ferromagnetic material H01Q7/02 takes precedence
• CPC Class Codes: H01Q 7/08 Ferrite rod or like elongated core

Abstract

A three-axis antenna chip includes a cross-shaped core made of a magnetic substance. The core includes an X-axis core piece and a Y-axis core piece. The core pieces are laid on top of each other such that the core pieces extend perpendicular to each other. An X-axis coil portion is provided about the X-axis core piece, and a Y-axis coil portion is provided about the Y-axis core piece. A Z-axis coil portion is provided about a Z-axis that is perpendicular to the X-axis core piece and the Y-axis core piece. The three-axis antenna chip thus constructed is advantageous in reducing the size.

Claims

1. A multiaxial antenna chip, comprising:

a core, which includes at least two arm portions, each arm portion extending in a direction different from the other arm portion; and

coil portions, wherein each arm portion has a coil portion provided about it.

2. The multiaxial antenna chip according to claim 1, wherein the core is shaped generally like a cross, wherein the arm portions include an X-axis arm portion and an Y-axis arm portion, the Y-axis arm portion extending perpendicular to the X-axis arm portion, and wherein the coil portions include an X-axis coil portion provided about the X-axis arm portion and an Y-axis coil portion provided about the Y-axis arm portion.

3. The multiaxial antenna chip according to claim 2, further comprising a Z-axis coil portion provided about a Z axis that extends perpendicular to the X-axis arm portion and the Y-axis arm portion.

4. The multiaxial antenna chip according to claim 3, wherein the cross-shaped core has four radially outer tips, and wherein the Z-axis coil portion formed by winding an electric wire along lines that are parallel to lines passing through the tips of the core.

5. The multiaxial antenna chip according to claim 4, wherein the Z-axis coil portion is arranged such that the Z-axis coil portion does not protrude radially outward beyond the tips of the core.

6. The multiaxial antenna chip according to claim 3, wherein the Z-axis coil portion is displaced from the core in relation to a direction of the Z-axis.

7. The multiaxial antenna chip according to claim 3, further comprising a casing for accommodating the core, wherein the Z-axis coil portion is wound about the casing.

8. The multiaxial antenna chip according to claim 3, further comprising a plurality of contacts, each contact being connected to one of the coil portions, wherein the contacts extend through, and are fixed to, a circuit board on which the multiaxial antenna chip is mounted.

9. The multiaxial antenna chip according to claim 8, wherein, when the multiaxial antenna chip is viewed along the Z axis, the contacts are arranged asymmetrically.

10. The multiaxial antenna chip according to claim 3, further comprising a claw portion, wherein the claw portion extends through, and is engaged with, a circuit board on which the multiaxial antenna chip is mounted.

11. The multiaxial antenna chip according to claim 2, wherein the core includes an X-axis core piece and a Y-axis core piece, wherein the core pieces extend perpendicular to each other and are laid on top of each other, and wherein the X-axis core piece includes the X-axis arm portion, and the Y-axis core piece includes the Y-axis arm portion.

12. The multiaxial antenna chip according to claim 11, wherein the core pieces are laid on top of each other such that portions of the core pieces that are not laid on top of each other are in the same plane.

13. The multiaxial antenna chip according to claim 11, wherein at least one of the core pieces has a concave portion at a section that is laid on top of the other core piece, wherein the other core piece is engaged with the concave portion.

14. The multiaxial antenna chip according to claim 11, wherein at least one of the core pieces is bent such that a section that is laid on top of the other core piece is displaced relative to the remainder of the bent core piece in a direction away from the other core piece.

15. The multiaxial antenna chip according to claim 2, wherein the X-axis arm portion is a pair of X-axis arm portions that extend in opposite directions from a center of the core, wherein the Y-axis arm portion is a pair of Y-axis arm portions that extend in opposite directions from the center of the core, wherein the X-axis coil portion is a pair of X-axis coil portions, each corresponding to one of the X-axis arm portions, and wherein the Y-axis coil portion is a pair of Y-axis coil portions, each corresponding to one of the Y-axis arm portions.

16. The multiaxial antenna chip according to claim 11, wherein the X-axis coil portion is provided only in a section of the X-axis core piece that is not laid on top of the Y-axis core piece, and wherein the Y-axis coil portion is provided only in a section of the Y-axis core piece that is not laid on top of the X axis core piece.

17. The multiaxial antenna chip according to claim 11, wherein the X-axis coil portion is provided both in a section of the X-axis core piece that is laid on top of the Y-axis core piece and in a section of the X-axis core piece that is not laid on top of the Y-axis core piece, and wherein the Y-axis coil portion is provided both in a section of the Y-axis core piece that is laid on top of the X-axis core piece and in a section of the Y-axis core piece that is not laid on top of the X-axis core piece.

18. The multiaxial antenna according to claim 1, wherein the core is flexible.

19. The multiaxial antenna according to claim 18, wherein the core is constructed by stacking a plurality of flexible sheets.

20. The multiaxial antenna chip according to claim 7, wherein the core includes an X-axis core piece and a Y-axis core piece, wherein the core pieces extend perpendicular to each other and are laid on top of each other, and wherein the X-axis core piece includes the X-axis arm portion, and the Y-axis core piece includes the Y-axis arm portion.

21. The multiaxial antenna chip according to claim 20, further comprising a plurality of contacts, each contact being connected to one of the coil portions, wherein the contacts extend through, and are fixed to, a circuit board on which the multiaxial antenna chip is mounted.