Transformer bobbin

A bobbin of a transformer, comprising:

• a hollow polyhedron sleeve having a first port and a second port, the first port comprising a first copper wire that is wrapped around the sleeve to form a plurality of copper coils of the first port, the second port comprising a second copper wire that is wrapped around the sleeve to form a plurality of copper coils of the second port, the hollow polyhedron sleeve having a first winding-started point at a first corner of the hollow polyhedron sleeve, and having a second winding-started point at a second corner of the hollow polyhedron sleeve, the first copper wire starting to wrap around the hollow polyhedron sleeve from one of the first winding-started point and the second winding-started point;
• a first pin set installed on an end of the first port, and having:
• a first pin and a second pint, each from being wrapped around by a starting point of the first copper wire;
• a first griding slot for placing a copper wire segment from the first pin to the first winding-started point when the first copper wire is wrapped around the sleeve in a first direction;
• a second griding slot for placing the copper wire segment from the second pin to the second winding-started point when the first copper wire is wrapped around the sleeve in a second direction that is converse to the first direction;
• and
• a first isolating block located on the first pin set and near the hollow polyhedron sleeve;
• and
• a second pin set installed on an end of the second port, and having a third pin and a fourth pin, the third pin and the fourth pin being wrapped around by a starting point and a terminal point of the second copper wire, respectively;
• wherein the first corner of the hollow polyhedron sleeve is an intersection point of a top plane and a side plane of the hollow polyhedron sleeve, and the second corner of the hollow polyhedron sleeve is an intersection point of the top plane and another side plane of the polyhedron hollow sleeve.