Ring core transformer with ribbon core for low frequency duty - uses core material wound round finished coil winding

摘要

The ribbon is wound using a modified coil winding machine to thread the strip (5) through the hole (3) in the centre of the coil (1) and bring it round the outside of the winding to form a continuously wound core (7). The finished core may be bonded together with a suitable adhesive to give a mechanically stable structure. The strip material is typically 0.05mm thick with a width of several millimeters. A small core may have about 200 turns of strip. In the construction and manufacture of ring core transformers the core is wound round the finished coil instead of fitting or winding the coil round a finished core. By employing a ribbon fo amorphous ferromagnetic steel no heat treatment is necessary after core winding to restore the magnetic characteristics.