Wire-winding structure and winding method

Abstract

This invention provides a coil structure and winding method, including a transformer and a common-mode choke. The transformer has a first iron core; the transformer's secondary winding has a first tap and a pair of differential signal lines, a first signal line and a second signal line; the common-mode choke has a pair of primary signal lines, a fifth single wire and a sixth single wire; the first signal line is formed by twisting the ends of the first and second single wires together, and the second signal line is formed by twisting the ends of the third and fourth single wires together; a first strand of three-strand wire and a second strand of three-strand wire are wound on the first iron core. The first strand of three-strand wire includes one of the first signal lines, one of the second signal lines, and one of the fifth or sixth single wires. This application achieves common-mode flux cancellation and reduces leakage inductance by using two strands of three-strand wire wound on the transformer T1.

Claims

1. A coil structure, comprising: A transformer and a common-mode choke are provided. The transformer has a first iron core. The secondary winding of the transformer has a first tap and a pair of differential signal lines—a first signal line and a second signal line. The common-mode choke has a pair of primary signal lines—a fifth single wire and a sixth single wire. The first signal line is made by twisting the ends of a first single wire and a second single wire (double wire), and the second signal line is made by twisting the ends of a third single wire and a fourth single wire (double wire). The first iron core is wound with a first strand of three-wire and a second strand of three-wire. The first strand of three-wire includes one of the first signal line (double wire), one of the second signal line (double wire), and one of the fifth and sixth single wires. The second strand of three-wire includes the other of the first signal line (double wire), the other of the second signal line (double wire), and the other of the fifth and sixth single wires. The first strand of three-stranded wire and the second strand of three-stranded wire are wound side by side on the first iron core of the transformer.

2. The coil structure as described in claim 1, wherein, The primary winding of the common-mode choke has a primary tap, a seventh single wire, and a pair of primary signal lines, a fifth single wire and a sixth single wire; the first tap and the seventh single wire are grounded; the first strand of three-wire and the second strand of three-wire are twisted clockwise on the first iron core of the transformer, with the twisting direction being consistent, and are wound together on the first iron core of the transformer; the starting ends of the first strand of three-wire and the starting ends of the second strand of three-wire are exposed on the outer side of the front of the first iron core of the transformer, and the ending ends of the first strand of three-wire and the ending ends of the second strand of three-wire are exposed on the outer side of the back of the first iron core of the transformer.

3. The coil structure as described in claim 1, wherein, The first strand of twisted wire is made by twisting the first single wire, the third single wire, and the fifth single wire in a clockwise direction; the second strand of twisted wire is made by twisting the second single wire, the fourth single wire, and the sixth single wire in a clockwise direction; the first strand of twisted wire and the second strand of twisted wire are wound side by side on the first iron core for six turns.

4. The coil structure as described in claim 2, wherein, The starting end of the first signal line is formed by twisting together the starting ends of the first single wire and the second single wire; the ending end of the second signal line is formed by twisting together the ending ends of the third single wire and the fourth single wire; the first signal line and the second signal line form the secondary coil of the transformer; the starting end of the first signal line forms the positive secondary terminal of the transformer, and the ending end of the second signal line forms the negative secondary terminal of the transformer; the starting end of the first signal line and the ending end of the second signal line form a pair of differential signal lines of the secondary coil of the transformer.

5. The coil structure as described in claim 4, wherein, The end of the first signal line is formed by twisting the end of the first single wire and the end of the second single wire together; the beginning of the second signal line is formed by twisting the beginning of the third single wire and the beginning of the fourth single wire together; the twisted pair of the end wires of the first signal line and the twisted pair of the beginning wires of the second signal line are then twisted together to form a four-wire twisted wire, which forms the first tap of the secondary coil of the transformer; the fifth single wire and the sixth single wire form the primary coil of the transformer; an additional seventh single wire is added, and the beginning of the seventh single wire is twisted together with the end of the fifth single wire and the beginning of the sixth single wire, forming a second tap of the secondary coil of the common mode choke.

6. The coil structure as described in claim 5, wherein, The end of the seventh wire, along with the beginning of the fifth wire and the end of the sixth wire, are twisted together to form a third strand of twisted wire. The twisting degree of this third strand is 12-16 knots / inch. This third strand of twisted wire is wound 5 times around the second iron core of the common mode choke, and is evenly distributed in 3 / 5 of the area of ​​the second iron core ring. The beginning of the fifth wire, the end of the sixth wire, and the end of the seventh wire are exposed outside the second iron core. The beginning of the fifth wire forms the primary positive electrode of the common mode choke, the end of the sixth wire forms the primary negative electrode of the common mode choke, and the end of the seventh wire forms the primary tap of the common mode choke.

7. The coil structure as described in claim 3, wherein, The first strand of twisted wire is made by twisting the first single wire, the third single wire, and the fifth single wire together, with a twist ratio of 16~24 knots / inch; the second strand of twisted wire is made by twisting the second single wire, the fourth single wire, and the sixth single wire together, with a twist ratio of 16~24 knots / inch; the first strand of twisted wire and the second strand of twisted wire are evenly distributed in the 2 / 3 area of ​​a first iron core ring.

8. The coil structure as described in claim 5, wherein, The twisted pair of the first signal line and the twisted pair of the second signal line have a twist ratio of 26~34 strands / inch; the twisted four-wire of the first tap has a twist ratio of 16~20 strands / inch; the twisted three-wire of the second tap has a twist ratio of 16~24 strands / inch; and the tap length is less than or equal to 6mm.

9. The coil structure as described in claim 5, wherein, The twisted pair of the first signal line starts from the front and wraps around the first tap and the second tap. After wrapping, the twisted pair of the first signal line rotates to the back of the first iron core and is led out. The twisted pair of the second signal line starts from the back and wraps around the first tap and the second tap. After wrapping, the twisted pair of the second signal line rotates to the front of the first iron core and is led out. The two wires, the first signal line and the second signal line, are bound together close to each other.

10. A method for winding a coil, comprising the following steps: Winding a transformer: Twisting a first single wire, a third single wire, and a fifth single wire together into a first strand of twisted wire; Twisting a second single wire, a fourth single wire, and a sixth single wire together into a second strand of twisted wire; Winding the first strand of twisted wire and the second strand of twisted wire side-by-side on a first iron core of a transformer; Fabricating the signal wire of the transformer: The ends of the first single wire and the second single-wire double wire are twisted together to form a first signal wire; the beginning ends of the first single wire and the beginning ends of the second single wire are twisted together to form the beginning end twisted pair of the first signal wire, and the beginning end of the first signal wire forms the secondary positive terminal of the transformer; and the ends of the third single wire and the fourth single wire double wire are twisted together to form a second signal wire; the end ends of the third single wire and the end ends of the fourth single wire are twisted together to form the end end twisted pair of the second signal wire, and the end end of the second signal wire forms the secondary negative terminal of the transformer.

11. The method for winding a coil as described in claim 10, wherein, The process also includes the following steps: Fabricating a first tap for a transformer: Take the end of a first single wire, the end of a second single wire, the beginning of a third single wire, and the beginning of a fourth single wire, and twist the ends of these four wires together to form the first tap for the transformer; Fabricating a second tap for a common-mode choke: Add an additional seventh single wire, and twist the beginning of this seventh single wire with the end of a fifth single wire and the beginning of a sixth single wire to form the second tap for the common-mode choke; Cut the second tap to within 6mm and pre-solder it. The length of the tin-dip section P at the end of the second tap is 1~2mm; Winding the common-mode choke: The end wire of the seventh single wire, the beginning wire of the fifth single wire, and the end wire of the sixth single wire are twisted together to form a third twisted wire. This third twisted wire passes through the second iron core of the common mode choke and is wound 5 times. The distance L between the transformer and the common mode choke is 1~2mm. The beginning wire, the end wire, and the end wire of the seventh single wire are exposed outside the second iron core. The beginning wire of the fifth single wire forms the primary positive terminal of the common mode choke, the end wire of the sixth single wire forms the primary negative terminal of the common mode choke, and the end wire of the seventh single wire forms the primary tap of the common mode choke. Signal wire twisting: The beginning wire of the first signal wire is twisted around the first tap and the second tap from the front. After twisting, the beginning wire of the first signal wire is rotated to the back of the first iron core and led out. The twisted pair of the end wire of the second signal line is wrapped around the first tap and the second tap from the back. After wrapping, the twisted pair of the end wire of the second signal line is rotated to the front of the first iron core and brought out. The beginning wire of the first signal line and the end wire of the second signal line are pulled together and bound.

12. The method for winding a coil as described in claim 11, wherein, The first, third, and fifth single wires are twisted clockwise to a twist ratio of 16-24 knots / inch, forming a first strand of three-wire twisted wire. The second, fourth, and sixth single wires are twisted clockwise to a twist ratio of 16-24 knots / inch, forming a second strand of three-wire twisted wire. The first and second strands of three-wire twisted wire are twisted in the same direction on the first iron core of the transformer, and are wound together on the first iron core of the transformer, making six turns, evenly distributed in 2 / 3 of the area of ​​the first iron core ring. The twist ratio of the second tap is 16-24 knots / inch. The third strand of three-wire twisted wire is evenly distributed in 3 / 5 of the area of ​​the second iron core ring of the common mode choke.

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