Patent ID: 8106737

Claim:
A terminal structure of a coil device, comprising: a coil that includes a bobbin and a rectangular conductive wire having a flattened quadrangular shape in cross section, wherein the wire is covered with a dielectric film and wound around the bobbin; and a terminal that includes a fusing part, wherein: an end portion of the wire, which extends out of the coil, has first and second flat surfaces that are opposed to each other, and the fusing part is electrically connected to the first and second flat surfaces by fusing; the fusing part includes: a planar portion that has a shape of a plate and is in surface contact with the first flat surface of the first and second flat surfaces; and a folded piece that extends from the planar portion and is folded in a direction perpendicular to a plane of the planar portion such that the end portion of the wire is clamped between the planar portion and the folded piece; the folded piece includes a contact surface portion which is in contact with the second flat surface; the contact surface portion includes a planar main part and a stepped portion that is shifted by a level difference Δt from the planar main part toward the second flat surface, wherein the planar main part and the stepped portion extend side by side in a longitudinal direction of the folding piece, which is perpendicular to a longitudinal direction of the end portion of the wire, wherein the planar main part and the stepped portion are arranged side by side in the longitudinal direction of the end portion of the wire, and wherein the planar main part and the stepped portion are shifted by the level difference Δt in a direction perpendicular to the longitudinal direction of the folding piece and perpendicular to the longitudinal direction of the end portion of the wire; and the stepped portion is in contact with the second flat surface to increase an amount of deformation of a contact area of the second flat surface which is in contact with the stepped portion, in comparison to an adjacent area of the second flat surface that is adjacent to the contact area.