A core component is made of a sintered body of an inorganic powder, in which the core component includes a columnar winding portion around which a conductive wire is wound, the columnar winding portion having a first axial end and a second axial end and a flange portion integrally formed with the winding portion at both axial ends of the winding portion, in which the columnar winding portion includes, in a cross section orthogonal to an axial center, a first region having a curved outer peripheral surface having a first radius of curvature and a second region having a curved surface having a second radius of curvature, the second radius of curvature is smaller than the first radius of curvature and the first region and the second region are connected with each other via a first projection.

An object is to improve a core and heat radiation properties from the coil, and to reduce the size of a transformer. In order to attain the object described above, a transformer includes a bobbin wound around with a coil, a columnar core center portion in which the bobbin is mounted, and a plurality of core leg portions joining both ends of the core center portion on the outside of the coil. The size of the core leg portion is larger than the size of the other core leg portions, and the core leg portion includes a flat outer circumferential surface approximately parallel to a surface which is tangent to an outer circumferential side surface of the coil. The transformer is disposed in a housing such that the outer circumferential surface of the core leg portion is tangent to a floor surface of the housing.

Disclosed herein are a method for analyzing heavy metal removal efficiency using phase difference analysis and an apparatus using the method. The method for analyzing heavy metal removal efficiency using phase difference analysis includes applying a magnetic field to a magnetite onto which a heavy metal is adsorbed, based on a first solenoid coil and a second solenoid coil that have an identical winding direction, applying a high-frequency signal to the magnetite, based on a third solenoid coil having a winding direction that differs from that of the first solenoid coil and the second solenoid coil, detecting a high-frequency signal transformed by the magnetite, and calculating a phase difference between a previously detected default high-frequency signal and the transformed high-frequency signal, and analyzing an efficiency of heavy metal removal by the magnetite by measuring a concentration of the heavy metal based on the phase difference.

A coil device includes a conductive wire forming a coil, a coil base having a groove for accommodating the conductive wire, and a stopper being separate from the coil base and attached to the coil base to cover the conductive wire. The stopper includes a base portion attached to the coil base at a position adjacent the groove, and a distal end portion integrated with the base portion to cover the conductive wire. The base portion of the stopper is rotatable. Alternatively, the distal end portion of the stopper is deformable.

A reactor includes a coil having a winding portion, and a magnetic core including a core piece having an inner core portion disposed inside the winding portion. The core piece is a compact made of a composite material that contains a magnetic powder and a resin. The reactor further includes: a first projection that is integrated with and projects from an outer peripheral face of the inner core portion, and comes into contact with an inner peripheral face of the winding portion so as to position the winding portion in a diameter direction of the winding portion, and a second projection that is integrated with and projects from the core piece at a position opposing an end face of the winding portion, and comes into contact with the end face of the winding portion so as to position the winding portion in an axial direction thereof.

A coil component includes a body and a coil conductor embedded in the body. The body includes a magnetic layer and a non-magnetic layer. The magnetic layer is formed of a composite material including a metal particle and a resin material, and the non-magnetic layer is arranged to block between at least one of top and bottom surfaces of the body and the coil conductor.

A surface-mounted inductor including a coil having a wound part formed by winding a conductive wire and extended parts extended from an outer circumference of the wound part, a molded body containing the coil, constituted by a composite material containing a magnetic powder, and outer terminals connected to end portions of the extended parts disposed on a mounting surface. The wound part is contained within the molded body so that a winding axis is parallel to the mounting surface. The extended parts are extended toward the mounting surface side, each end portion of the extended parts are exposed from the surface thereof of the molded body. In the molded body, a density of a magnetic powder between the end portions of the extended parts on the mounting-side surface is lower than a density in the surface on the opposite side from the mounting surface.

A transformer for an OBC of an electric vehicle includes: a housing; a cover for opening and closing a storage space of the housing; a plate-type primary coil embedded in the storage space of the housing and supplied with power from a charger side; and a plurality of plate-shaped secondary coils embedded in the storage space of the housing to independently generate an induced current by magnetic field induction from the primary coil and output the induced current to a high voltage battery, and according to this, there is an advantage of reducing the size and improving the product productivity.

A coil component includes a winding core that includes a winding core portion, a first flange portion, and a second flange portion. The coil component further includes a plate core that has a main surface facing the winding core portion, the first flange portion, and the second flange portion, that extends between the first flange portion and the second flange portion, and that is secured to the winding core by using adhesive. Each of the first flange portion and the second flange portion has an upper surface that faces the main surface of the plate core. Recessed portions are formed on the corresponding upper surfaces. Protrusions may be formed in corresponding regions in which the recessed portions are formed.

A wire-wound inductor component includes a core including an axial portion that extends in an axial direction and is pillar-shaped and a first support and a second support disposed respectively on a first end and a second end in the axial direction of the axial portion; a first terminal electrode and a second terminal electrode disposed respectively on a bottom face of the first support and a bottom face of the second support; a wire wound around the axial portion, with first and second end portions of the wire being connected respectively to the first and second terminal electrodes; and a cover member that covers at least part of the wire on an upper face of the axial portion and has a terminal indentation depth of 0.85 μm or more. The adhesive strength of a top face of the cover member is less than or equal to 3.28 gf/mm.sup.2.