To enable a terminal to be brazed to the tip end of a conductor without damaging insulation resin of a coil body, to prevent the conductor from vibrating at the time of energization with an electric current, and to prevent a short circuit between the conductors as well as fatigue failure of the conductors.

In the coil body 1, coil conductors are insulated and separated from each other by injecting resin between the coils. The coil body 1 is inserted into a workpiece and, by being applied with an electric current, impresses an electromagnetic force to the workpiece and expands it. From an end 2 of the coil body 1, a pair of conductors 3 are derived and embedded in a planar member 4 composed of insulation resin. The end of each conductor 3 is exposed outside from the insulation resin member 4, with the conductor 3 brazed to a terminal 7 at the exposed part. A lead wire 5 is connected to the terminal 7. The conductor 3 is shaped like a pipe in which a coolant flows through and is provided with an inlet and a discharge port 6 for the coolant at the end part.

COPYRIGHT: (C)2005,JPO&NCIPI