Patent ID: 8319595

Claim:
A coil apparatus that laminates a plurality of disc-type coils each having a conductor pattern constituting coils of at least one circuit on a discoid annular insulating substrate and electrically connects the disc-type coils via lamination through holes, which are configured to achieve electrical conduction with other disc-type coils, to use the plurality of laminated disc-type coils as one coil, wherein the plurality of laminated disc-type coils are disc-type coils of one-kind each having a configuration that the conductor pattern and a leading end and a terminating end for each circuit of the conductor pattern are provided at the same positions and the leading end and the terminating end are connected to the lamination through holes via a leading pattern and a terminating pattern, holes configured to form at least the n+l lamination through holes for n (n is a positive integer) laminated discs are provided in accordance with each circuit in each disc-type coil and arranged at the same positions in a laminating direction on the outer side or the inner side of the conductor pattern of the insulating substrate in a state that the plurality of discs are laminated, positions of the lamination through holes that connect the disc-type coils to be laminated are variable by just changing the positions of the holes configured to form the lamination through holes on the other side to which the leading pattern and the terminating pattern are connected, and the plurality of disc-type coils of one type constitute an arbitrary circuit.