Winding structure

A winding structure, comprising:

• a bobbin that has:
• a first end;
• a second end that is opposite to the first end;
• and
• a middle portion, located between the first end and the second end;
• a first coil that has:
• a first preceding winding segment;
• a first following winding segment;
• and
• a first link segment that connects the first preceding winding segment and the first following winding segment;
• a second coil that has:
• a second preceding winding segment;
• a second following winding segment;
• and
• a second link segment that connects the second preceding winding segment and the second following winding segment;
• wherein:
• the first preceding winding segment starts winding from the first end of the bobbin to the middle portion along an axial direction of the bobbin, so that the first preceding winding segment has a plurality of first preceding loops that are in contact with a winding surface of the bobbin;
• the second preceding winding segment starts winding from the second end of the bobbin to the middle portion along the axial direction of the bobbin, so that the second preceding winding segment has a plurality of second preceding loops that are in contact with the winding surface of the bobbin;
• the first link segment and the second link segment are crossed at the middle portion;
• the first following winding segment winds from the middle portion to the second end along the axial direction of the bobbin, so that the first following winding segment has a plurality of first following loops that wind on the second preceding loops;
• and
• the second following winding segment winds from the middle portion to the first end along the axial direction of the bobbin, so that the second following winding segment has a plurality of second following loops that wind on the first preceding loops.