EL light emitting unit, power feeding unit and EL light emitting device

• US 20050093480A1
• Filed: 08/24/2004
• Published: 05/05/2005
• Est. Priority Date: 08/26/2003
• Status: Active Grant

• Current Assignee: RISO Kagaku Corporation
• Original Assignee: RISO Kagaku Corporation
• Inventors: Shibasaki, Akira, Kuramochi, Mitsuru
• Granted Patent: US 7,095,177 B2
• Time in Patent Office: Days
• US Class Current: 315/248
• CPC Class Codes: H05B 44/00 Circuit arrangements for operating electroluminescent light sources for operating light emitting diodes H05B45/00
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

EL light emitting device includes a cylindrical EL light emitting unit and a columnar power feeding unit. EL light emitting unit is composed such that a cylindrical receiver coil is arranged and connected along an inner circumferential face of the cylindrical EL light emitting element and integrated into a single body by an outer cover member. The power feeding unit is formed in a columnar shape whose diameter is smaller than an inner diameter of EL light emitting unit so that the power feeding unit can be inserted into the cylindrical EL light emitting unit. When the power feeding unit is inserted into EL light emitting unit and the power feeding unit is impressed with an alternating voltage, a high alternating voltage corresponding to the turn rate of both coils is generated in the receiver coil, so that light can be emitted from EL light emitting element.

Claims

1. An EL light emitting unit comprising:

an EL light emitting element; and

a power receiving coil connected to the EL light emitting element by electromagnetic induction so that a predetermined AC current is induced therein,

wherein the EL light emitting element and the power receiving coil are integrated with each other, and the EL light emitting element and the power receiving coil are entirely sealed by an first outer cover member.

2. An EL light emitting unit according to claim 1, wherein the EL light emitting element is formed in a cylindrical shape, the power receiving coil is formed in a cylindrical shape being arranged along an inner circumferential face of the EL light emitting element and the first outer cover member is formed in a cylindrical shape capable of covering entirely the EL light emitting element and the power receiving element.

3. An EL light emitting unit according to claim 1, wherein the EL light emitting element is formed in a sheet-shape, the power receiving coil is arranged along a surface of the EL light emitting element and the first outer cover member is formed in a sheet-shape capable of covering entirely the EL light emitting element and the power receiving element.

4. An EL light emitting unit according to claim 1, wherein the power receiving coil is formed in an annular body, the EL light emitting element is formed in an annular-shape along the power receiving coil so that the EL light emitting element covers a surface of the annular body of the power receiving coil.

5. An EL light emitting unit according to claim 4, wherein

the EL light emitting element includes:

a central electrode provided on a surface of the annular body of the power receiving coil via an insulating layer;

a light emitting layer provided on a surface of the central electrode via an insulating layer;

a transparent electrode provided on a surface of the light emitting layer via an insulating layer;

an additional electrode wound around a surface of the transparent electrode; and

the first outer cover member for covering the transparent electrode and the additional electrode;

wherein one end of the power receiving coil is connected to the central electrode, and another end of the power receiving coil is connected to the additional electrode.

6. An EL light emitting unit according to claim 4, wherein a plurality of the EL light emitting elements are provided, each of which includes a linear structure comprising:

an annular central electrode;

a light emitting layer provided on a surface of the central electrode via an insulating layer;

a transparent electrode provided on a surface of the light emitting layer via an insulating layer;

an additional electrode wound around a surface of the transparent electrode; and

a second outer cover member for covering the transparent electrode and the additional electrode,

wherein the EL light emitting elements are densely arranged in a circumferential direction along a surface of the annular body of the power receiving coil,

one end of the power receiving coil is connected to the central electrodes of the EL light emitting elements, another end of the power receiving coil is connected to the additional electrodes of the EL light emitting elements, and

the EL light emitting elements and the power receiving coil are covered with the first outer cover member.

7. A power feeding unit comprising:

a power feeding coil connected to an EL light emitting element by electromagnetic induction so that a predetermined AC current is induced therein; and

a power feeding section for giving an AC current to the power feeding coil.

8. A power feeding unit according to claim 7, wherein the power feeding coil is formed in a columnar shape whose diameter is smaller than an inner diameter of the power receiving coil so that the power feeding coil is insertable into the power receiving coil which is formed in a cylindrical shape.

9. A power feeding unit according to claim 7, wherein the power feeding coil is wound around a magnetic body having a recess portion, and

a part of the sheet-shaped power receiving coil which is wound on a plane is arranged in the recess portion.

10. A power feeding unit according to claim 7, wherein the power feeding coil is wound around a split of a cylindrical core which is attachable from outside, and

the power feeding coil is movable with respect to the power receiving coil which is formed in an annular body.

11. A power feeding unit according to claim 7, wherein the power feeding section is configured to intermittently drive the power feeding coil, and the power feeding coil is continuously driven in a case that the power receiving coil and the power feeding coil come close to each other, in which an electric current not less than or more than a predetermined value flows in the power feeding coil.

12. An EL light emitting device comprising:

an EL light emitting unit in which an EL light emitting element and a power receiving coil connected to the EL light emitting element so that a predetermined AC current is induced by electromagnetic induction, are integrated with each other; and

a power feeding unit having a power feeding coil, which induces the predetermined AC current in the power receiving coil of the EL light emitting unit by electromagnetic induction, and a power feeding section for giving an AC current to the power feeding coil.

13. An EL light emitting device according to claim 12, wherein

the EL light emitting element in the EL light emitting unit is formed in a cylindrical shape, the power receiving coil is formed in a cylindrical shape being arranged along an inner circumferential face of the EL light emitting element, and the EL light emitting element and the power receiving coil are integrated with each other by a cylindrical first outer cover member, and

the power feeding coil in the power feeding unit is formed in a cylindrical shape, whose diameter is smaller than an inner diameter of the power receiving coil so that the power feeding coil is insertable into the power receiving coil formed in a cylindrical shape.

14. An EL light emitting device according to claim 12, wherein the EL light emitting element in the EL light emitting unit is formed in a sheet-shape, and the power receiving coil is arranged along a surface of the EL light emitting element, so that the EL light emitting element and the power receiving coil are integrated with each other by a sheet-shaped first outer cover member, and

the power feeding coil in the power feeding unit is wound around a first magnetic body having a recess portion, and

the first magnetic body is attracted by a magnetic force to a second magnetic body for coupling magnetic fields which is arranged on an opposite side of the EL light emitting unit;

wherein a part of the power receiving coil is arranged in the recess portion of the first magnetic body.

15. An EL light emitting device according to claim 12, wherein the EL light emitting element in the EL light emitting unit includes

a central electrode provided on a surface of the annular body of the power receiving coil which is formed in an annular body via an insulating layer,

a light emitting layer provided on a surface of the central electrode via an insulating layer,

a transparent electrode provided on a surface of the light emitting layer via an insulating layer,

an additional electrode wound around a surface of the transparent electrode, and

the first outer cover member for covering the transparent electrode and the additional electrode;

one end of the power receiving coil is connected to the central electrode and another end of the power receiving coil is connected to the additional electrode; and

the power feeding coil in the power feeding unit is wound around a split of a cylindrical core being attachable from outside so as to be movable with respect to the annular EL light emitting unit.

16. An EL light emitting device according to claim 12, wherein a plurality of the EL light emitting elements are provided in the EL light emitting unit, each of which is formed in a linear structure including:

an annular central electrode,

a light emitting layer provided on a surface of the central electrode via an insulating layer,

a transparent electrode provided on a surface of the light emitting layer via an insulating layer,

an additional electrode wound around a surface of the transparent electrode, and

a second outer cover member for covering the transparent electrode and the additional electrode;

the EL light emitting elements are densely arranged in a circumferential direction on a surface of the annular body of the power receiving coil;

wherein one end of the power receiving coil is connected to the central electrodes of the EL light emitting elements, another end of the power receiving coil is connected to the additional electrodes of the EL light emitting elements; and

the EL light emitting elements and the power receiving coil are covered with the first outer cover member;

the power feeding coil in the power feeding unit is wound around a split of a cylindrical core being attachable from outside so as to be movable with respect to the annular EL light emitting unit.

17. An EL light emitting device according to claim 12, wherein a ratio of the number of turns of the power feeding coil to that of the power receiving coil is not less than 1 to 10.