Double insulated transformer and bobbin case thereof

Abstract

A bobbin case for use in a transformer of the double-insulated type comprises an insulating member of tube-like shape, a partition wall disposed substantially normal to the axis of the insulating member so that the inner space of said insulating member is divided into two recesses for receiving primary and secondary winding assemblies, respectively, from the opposite directions along the axis of said insulating member, and a pair of insulating rims which extend from the outer end surfaces of the insulating member at the side of the recess for receiving the primary winding assembly. The pair of insulating rims are formed such that they are capable of being bent inwardly along the outer end surfaces so as to obtain a creeping distance between said primary winding and a core inserted into center holes in said winding assemblies. By using the bobbin case, the insertion of the primary and secondary winding assemblies can easily and efficiently be carried out. A bobbin case according to another aspect of the invention is provided integrally with protecting legs for soldering portions between connected pins and terminal portions of the winding assemblies. The protecting legs are also utilized in hanging a transformer having the bobbin case.