Abstract: A transformer comprising a core, a primary winding and a secondary winding in which one of the windings, preferably the winding with the least coils, is formed from a tubular member formed in a plurality of coils; in the preferred embodiment of a step down transformer, the secondary winding is formed from a tubular member. A connector block at each end of the secondary winding includes an appropriate fluid passage and means for connecting a fluid coupling to the block so that the inlet and outlet of the fluid circulation system can be secured to the tubular member forming the secondary winding. The loops of the primary coil are interdigitally arranged with the loops of the secondary coil so that the fluid in the secondary coil absorbs heat from both the primary and secondary windings. Each loop of the secondary includes a bow so that adjacent ends of each loop of the primary are sandwiched between the bows.

Abstract: A transformer comprising a core, a primary winding and a secondary winding in which one of the windings, preferably the winding with the least coils, is formed from a tubular member formed in a plurality of coils in the preferred embodiment of a step down transformer, the secondary winding is formed from a tubular member. A connector block at each end of the secondary winding includes an appropriate fluid passage and means for connecting a fluid coupling to the block so that the inlet and outlet of the fluid circulation system can be secured to the tubular member forming the secondary winding. The connector blocks also include threaded apertures adapted to receive the bolt for providing an electrical connection to an electrical apparatus such as a welding gun. The loops of the primary coil are interdigitally arranged with the loops of the secondary coil so that the fluid in the secondary coil absorbs heat from both the primary and secondary windings.