Patent ID: 8487732

Claim:
A coil transformer composed of a unit configuration in which a plurality of coil units each having an edgewise winding wire having n number of windings are prepared, wherein: each coil unit, being removably attachable from each other, has a winding start terminal disposed near one of the end faces (winding start-side end face) and a winding end terminal disposed near the other end face (winding end-side end face), and at least one tap draw-out terminal having a smaller number of windings than n windings, the end faces being arranged to oppose one another so that contact faces of the respective coil units have equal potentials, wherein selected terminals out of the tap draw-out terminals positioned close to each other in the opposed arrangement are connected, with one winding start terminal near the end face positioned on the uppermost side or the winding start terminal near the end face positioned on the lowermost side set as the winding start terminal and the other one set as the winding end terminal, so that a transformer having a desired number of windings can be configured, wherein the tap draw-out terminals are configured as tap switch terminals and connection terminals configured to connect the respective coil units, and a selected tap switch terminal of one of the coil units is configured to connect to another selected tap switch terminal of the another coil unit with an inter-terminal connection, such that by changing the selected terminals that are connected with each other, the number of windings may vary from the n windings.