MAGNETIC MODULE, HOLLOW COIL AND COMPOSITE WIRE THEREOF

A composite wire is provided. The composite wire includes a single core wire, a plurality of twisted wires, and an insulation layer. In a cross section of the composite wire, the twisted wires surround the single core wire. The twisted wires are configured along the circumferential direction of the single core wire. Each twisted wire comprises a plurality of conductive wires. The insulation layer covers the twisted wires. Each conductive wire has a conductive wire diameter, and the single core wire diameter of the single core wire is greater than the conductive wire diameter.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application claims priority of China Patent Application No. 202310337119.7, filed on Mar. 31, 2023, the entirety of which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a composite wire, and, in particular, to a composite wire adapted to form a hollow coil.

Description of the Related Art

In conventional switching power supply transformers, LITZ wires are utilized to form coils. The LITZ wires surround the lead frame to form the coil. The coil is supported by the lead frame. Conventionally, the thickness of the lead frame needs to be at least 0.6 mm to avoid short-circuiting between the LITZ wire and the iron core. The LITZ wire can easily scatter during the winding process, which increases the difficulty of manufacturing. Additionally, a conventional coil must be supported by a lead frame, and the coil cannot be flattened.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention provides a composite wire. The composite wire includes a single core wire, a plurality of twisted wires, and an insulation layer. In a cross section of the composite wire, the twisted wires surround the single core wire. The twisted wires are configured along the circumferential direction of the single core wire. Each twisted wire comprises a plurality of conductive wires. The insulation layer covers the twisted wires. Each conductive wire has a conductive wire diameter, and the single core wire diameter of the single core wire is greater than the conductive wire diameter.

In one embodiment, the single core wire diameter is greater than four times the conductive wire diameter.

In one embodiment, the single core wire diameter is greater than the twisted wire diameter of the twisted wire.

In one embodiment, the single core wire diameter is greater than two times the twisted wire diameter.

In one embodiment, the single core wire is a single core enameled wire.

In one embodiment, the composite wire further comprises a first adhesive layer, wherein the first adhesive layer is disposed on an inner side of the insulation layer, and the twisted wires are attached to the insulation layer by the first adhesive layer.

In one embodiment, the composite wire further comprises a second adhesive layer, wherein the second adhesive layer is disposed between the twisted wires and the single core wire.

In another embodiment, a hollow coil is provided. The hollow coil includes a composite wire. The composite wire extends along a spiral path. The composite wire includes a single core wire, a plurality of twisted wires, and an insulation layer. In a cross section of the composite wire, the twisted wires surround the single core wire. The twisted wires are configured along the circumferential direction of the single core wire. Each twisted wire comprises a plurality of conductive wires. The insulation layer covers the twisted wires. Each conductive wire has a conductive wire diameter, and the single core wire diameter of the single core wire is greater than the conductive wire diameter.

In another embodiment, a magnetic module is provided. The magnetic module includes an iron core unit and a composite wire. The composite wire surrounds the iron core unit. The composite wire includes a single core wire, a plurality of twisted wires, and an insulation layer. In a cross section of the composite wire, the twisted wires surround the single core wire. The twisted wires are configured along the circumferential direction of the single core wire. Each twisted wire comprises a plurality of conductive wires. The insulation layer covers the twisted wires. Each conductive wire has a conductive wire diameter, and the single core wire diameter of the single core wire is greater than the conductive wire diameter.

In the composite wire of the embodiment of the invention, the single core wire has thicker diameter, and provides structure support for the composite wire. The composite wire can be wound automatically. Compared with the conventional art, the coil of the embodiment of the invention has decreased manufacturing cost and improved reliability. Additionally, the coil of the embodiment of the invention can be flattened, and has improved stress resistance (for example, 1500 Vac). When the coil of the embodiment of the invention is combined with the lead frame, the thickness of the lead frame can be reduced because the lead frame does not need to provide the supporting function.

DETAILED DESCRIPTION OF THE INVENTION

FIG.1shows a hollow coil of the embodiment of the invention.FIG.2is a cross sectional view of the composite wire of a first embodiment of the invention. With reference toFIGS.1and2, the hollow coil C of the embodiment of the invention includes a composite wire L. The composite wire L extends along a spiral path. The composite wire L includes a single core wire1, a plurality of twisted wires21and an insulation layer30. In a cross section of the composite wire L, the twisted wires21surround the single core wire1. The twisted wires21are configured along the circumferential direction of the single core wire1. Each twisted wire21comprises a plurality of conductive wires23. The insulation layer30covers the twisted wires21. Each conductive wire23has a conductive wire diameter d2, and the single core wire diameter d1of the single core wire1is greater than the conductive wire diameter d2. The single core wire1provides structural support for the hollow coil C.

With reference toFIG.2, in one embodiment, the single core wire diameter d1is greater than four times the conductive wire diameter d2. Therefore, the single core wire1provides sufficient structural support for the hollow coil C.

With reference toFIG.2, in one embodiment, the single core wire1is a single core enameled wire.

With reference toFIG.2, in one embodiment, the composite wire L further comprises a first adhesive layer31. The first adhesive layer31is disposed on an inner side of the insulation layer30. The twisted wires21are attached to the insulation layer30by the first adhesive layer31. The insulation layer30and the first adhesive layer31restrict the twisted wires21. In one embodiment, the insulation layer30can be made of plastic or other insulation materials.

FIG.3is a cross sectional view of the composite wire of a second embodiment of the invention. With reference toFIG.3, the composite wire L2of the second embodiment includes a single core wire1, a plurality of twisted wires22and an insulation layer30. Each twisted wire22comprises a plurality of conductive wires24. In this embodiment, the single core wire diameter d1of the single core wire1is greater than the twisted wire diameter d3of each twisted wire22. The single core wire1thus provides additional structural support for the hollow coil C.

With reference toFIG.3, in one embodiment, the single core wire diameter d1is greater than two times the twisted wire diameter d3. The single core wire1thus provides sufficient structural support for the hollow coil C.

With reference toFIG.3, in one embodiment, the composite wire L2further comprises a second adhesive layer32. The second adhesive layer32is disposed between the twisted wires22and the single core wire1. The second adhesive layer32restrict the twisted wires22.

FIG.4Ais a perspective view of a magnetic module of an embodiment of the invention.FIG.4Bis an exploded view of the magnetic module of the embodiment of the invention. With reference toFIGS.4A and4B, in another embodiment, a magnetic module M1is provided. The magnetic module M1includes an iron core unit4and a composite wire L. The iron core unit4includes a first iron core41and a second iron core42. The first iron core41has a first post411. The second iron core42has a second post421. The composite wire L surrounds the first post411and the second post421of the iron core unit4. The composite wire L surrounds at least a portion of the iron core unit4.

With reference toFIGS.4A and4B, in one embodiment, the magnetic module M1further comprises a lead frame51. The lead frame51is disposed between the first iron core41and the second iron core42. The lead frame51includes a base511and a plurality of pins512. The pins512are disposed on the base511. The composite wire L is disposed on the lead frame51and connected to the pins512.

With reference toFIGS.4A and4B, in one embodiment, at least a portion of the composite wire L is sandwiched between the first iron core41and the second iron core42.

FIG.5shows a portion of a magnetic module of another embodiment of the invention. With reference toFIG.5, the magnetic module has a lead frame52. The lead frame52comprises a base521. The base521has a plurality through holes522. The composite wire L is disposed on the lead frame52and passes through the through holes522. In this embodiment, the through holes522restrict the position of the composite wire L.

In the composite wire of the embodiment of the invention, the single core wire has thicker diameter, and provides structure support for the composite wire. The composite wire can be wound automatically. Compared with the conventional art, the coil of the embodiment of the invention has decreased manufacturing cost and improved reliability. Additionally, the coil of the embodiment of the invention can be flattened, and has improved stress resistance (for example, 1500 Vac). When the coil of the embodiment of the invention is combined with the lead frame, the thickness of the lead frame can be reduced because the lead frame does not need to provide the supporting function.