A method of manufacturing a laminated iron core includes: inserting a plurality of electrical steel strips in a superposed state to feed rolls including a pair of upper and lower feed rolls that are driven by a drive device to feed the electrical steel strips in a superposed state into a die having a plurality of punching processes in sequence; joining a part or all of the superposed electrical steel strips together before entering the die or at an upstream stage portion of the die after feeding out the electrical steel strips from the pair of upper and lower feed rolls; and punching simultaneously the plurality of electrical steel strips in a superposed state in the die.

A wound core (10) is a wound core including a portion in which grain-oriented electrical steel sheets (1) in which planar portions (4) and bent portions (5) are alternately continuous in a longitudinal direction are stacked in a sheet thickness direction and formed by stacking the grain-oriented electrical steel sheets (1) that have been individually bent in layers and assembled into a wound shape, wherein, when an average length of a roughness curve element in a width direction intersecting the longitudinal direction forming a surface of the bent portion (5) of the grain-oriented electrical steel sheet (1) is RSm(b), and an average length of the roughness curve element in the width direction forming a surface of the planar portion 4 of the grain-oriented electrical steel sheet (1) is RSm(s), the relationship of 1.00<RSm(b)/RSm(s)≤5.00 is satisfied.

A core for a transformer includes a multiplicity of bent metal sheets that are all connected to form a structure which surrounds a core opening and forms the core. The sheet ends of each of the metal sheet do not touch one another within the core. The metal sheets together with the core form at least one air gap at the respective sheet ends within the core or at a periphery of the core. The core is impregnated or coated, at least at the sheet ends of the metal sheets, with a lacquer or coating that contains magnetic particles. The impregnation or coating fills at least the air gaps at the sheet ends of the metal sheets. A method for producing a transformer having a core is also provided.

An electromagnetic device is disclosed, the electromagnetic device comprising a core support having an exterior surface comprising at least one radial protrusion, a tubular magnetic core positioned around a portion of the length of the core support, the tubular magnetic core having an interior surface, at least one indent located in the interior surface of the tubular magnetic core, wherein the at least one protrusion is located within the at least one indent to prevent relative longitudinal movement between the core support and tubular magnetic core, and a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the tubular magnetic core.

To prevent an adhesive agent from adhering to a die set for outer shape punching and avoid contamination of the die set by the adhesive agent even if the adhesive agent protrudes from the outer shape contour of a laminated iron core, a laminated iron core manufacturing device includes: a first punch (32) and a first die (48) for punching a part of an outer shape of each iron core lamina in a sheet steel strip; an adhesive agent applying apparatus (60) configured to apply an adhesive agent on an adhesive agent application region including a portion defined in the sheet steel strip by punching by the first punch (32) and the first die 48; and a second punch (34) and a second die (50) configured to punch the outer shape of each iron core lamina other than the part punched by the first punch (32) and the first die (48) from the sheet steel strip.

Disclosed is a method of manufacturing a magnetic field shielding sheet. The method of manufacturing a magnetic field shielding sheet formed as a plurality of divided pieces includes preparing a magnetic sheet formed of a magnetic material and having a first area and punching the magnetic sheet to form a shielding sheet using a mold such that the shielding sheet having a second area which is narrower than the first area is separated from the magnetic sheet, wherein the punching of the magnetic sheet to form the shielding sheet includes forming at least one linear slit in an inner region of the second area using the mold such that the shielding sheet is divided into a plurality of pieces while the shielding sheet is separated from the magnetic sheet to have the second area.

A laminated core manufacturing device includes: an overlapping unit configured to overlap the plurality of laminated core materials conveyed along different conveyance routes; an edge position correction unit configured to align edge positions in a width direction of the plurality of laminated core materials between the plurality of laminated core materials and to correct shift of each edge position of the plurality of laminated core materials with respect to a standard edge position; an uplift prevention unit configured to prevent uplift of the plurality of laminated core materials; and a punching unit configured to punch out the plurality of laminated core materials which are overlapped by the overlapping unit and have been subjected to a process to align the edge positions and to correct shift of the edge positions performed by the edge position correction unit, and a process to prevent the uplift performed by the uplift prevention unit.

A wound core is formed by laminating a plurality of bent bodies formed from a grain-oriented electrical steel sheet having a coating containing phosphorus formed on a surface, in a sheet thickness direction of the grain-oriented electrical steel sheet, in which the bent body is formed in a rectangular shape by having four flat portions and four corner portions adjacent to the flat portions, the corner portion has a bent region having a total bending angle of approximately 90 in a side view, the number of deformation twins present in the bent region in the side view is five or less per 1 mm of a length of a center line in the bent region in the sheet thickness direction, and the amount of phosphorus eluted from the corner portion in a case of being boiled in water for 30 minutes is 6.0 mg or less per 1 m.sup.2 of a surface area of the corner portion.

An inductor manufacturing method includes making a coil with a wire member, the coil has two end portions, bending a dependent segment from one end portion of the coil, and bending a lateral extension from the dependent segment, bending a bent segment from the second end portion of the coil, and bending a lateral segment from the bent segment, a base member is then engaged into a space between the coil and the lateral extension and the lateral segment of the coil for forming a coil assembly, the coil assembly is then engaged into a mold cavity of a mold device and punched together with an iron powder, the lateral extension and the lateral segment of the coil are electroplated with an electroplating layer.

Provided is a motor capable of having an improved output while keeping the mechanical strength of the stator core. A motor includes: a stator including a stator core including an annular yoke having an outer part and an inner part and teeth extending inwardly from the inner part of the yoke, and a coil wound around the teeth; and a rotor rotatably disposed inside of the stator. The stator core includes the lamination of sheet members made of a soft magnetic material. Each sheet member has a binding part to bind the sheet members in the lamination at a first part corresponding to the outer part of the yoke. At least the binding part of the first part is made of an amorphous soft magnetic material. The sheet member has a second part other than the first part, and the second part is made of a nanocrystal soft magnetic material.