Abstract: A transformer includes a covering member, a bobbin, a primary winding coil, plural secondary winding coils, and a magnetic core assembly. The covering member includes plural pins. The bobbin is combined with the covering member, and includes a bobbin body and a channel. A first winding section and plural single-trough second winding sections are defined on the bobbin body. The single-trough second winding sections are arranged at bilateral sides of the first winding section. The channel runs through the bobbin body. The primary winding coil is wound around the first winding section of the bobbin, and connected with the pins. The secondary winding coils are wound around respective single-trough second winding sections of the bobbin. The magnetic core assembly is partially embedded into the channel of the bobbin.

Abstract: A transformer includes a bobbin assembly, a magnetic core covering element, and a magnetic core assembly. The bobbin assembly includes a primary bobbin, a first secondary bobbin and a first channel. The primary bobbin includes a first sheathing part. At least one primary winding coil is wound around the primary bobbin. The first sheathing part has a first receptacle. A separation structure is formed within the first receptacle. The first secondary bobbin is accommodated within the first receptacle. A first secondary winding coil is wound around the first secondary bobbin and includes a wound segment and a returned segment. The wound segment and the returned segment are separated from each other by the separation structure. The magnetic core covering element is coupled with the bobbin assembly, and includes a second channel. The magnetic core assembly is partially embedded into the first channel and the second channel.

Abstract: A transformer. The transformer comprises a bobbin, a first core and a second core. The bobbin comprises a primary winding area and a secondary winding area. The first core is disposed in the bobbin. The second core is mounted on the bobbin. The second core comprises a plurality of first protrusions which are disposed at two sides of the bobbin. A second protrusion is integrally formed on the second core and is disposed between the first protrusions. The second protrusion is disposed between the primary winding area and the secondary winding area.

Abstract: A transformer. The transformer comprises a bobbin, a first core and a second core. The bobbin comprises a primary winding area and a secondary winding area. The first core is disposed in the bobbin. The second core is mounted on the bobbin. The second core comprises a plurality of first protrusions which are disposed at two sides of the bobbin. A second protrusion is integrally formed on the second core and is disposed between the first protrusions. The second protrusion is disposed between the primary winding area and the secondary winding area.