Abstract: A wound and laminated iron core is formed by winding a soft magnetic thin strip into a circular ring shape or elliptical ring shape. A coil is then wound around almost an entire outer periphery of the ring of wound and laminated iron core. A cross sectional shape of the wound and laminated iron core vertical to a peripheral direction of the ring is any one of: (i) a circular shape, (ii) an elliptical shape, (iii) a substantially regular polygon of at least 6 sides, (iv) a shape encircled by a pair of point-symmetrically positioned circular arcs or elliptical arcs with a nearly straight line connecting respective edges of the pair of circular arcs or elliptical arcs on both sides of the pair of circular arcs or elliptical arcs, and (v) a shape of a substantially regular polygon of at least 4 sides whose apexes comprise a circular arc or an elliptical arc.

Abstract: A wound core for a toroidal transformer has an improved shape, for example, circular or elliptic longitudinal ends in section, to properly attach a coil (toroidal winding) to the wound core. Therefore, the wound core allows a toroidal transformer that employs the wound core to achieve full performance, and improves the productivity of the toroidal transformers.

Abstract: A wound core for a toroidal transformer has an improved shape, for example, circular or elliptic longitudinal ends in section, to properly attach a coil (toroidal winding) to the wound core. Therefore, the wound core allows a toroidal transformer that employs the wound core to achieve full performance, and improves the productivity of the toroidal transformers.

Abstract: A wound and laminated iron core is formed by winding a soft magnetic thin strip into a circular ring shape or elliptical ring shape. A coil is then wound around almost an entire outer periphery of the ring of wound and laminated iron core. A cross sectional shape of the wound and laminated iron core vertical to a peripheral direction of the ring is any one of: (i) a circular shape, (ii) an elliptical shape, (iii) a substantially regular polygon of at least 6 sides, (iv) a shape encircled by a pair of point-symmetrically positioned circular arcs or elliptical arcs with a nearly straight line connecting respective edges of the pair of circular arcs or elliptical arcs on both sides of the pair of circular arcs or elliptical arcs, and (v) a shape of a substantially regular polygon of at least 4 sides whose apexes comprise a circular arc or an elliptical arc.

Abstract: A cutting apparatus for a strip of a ribbon core comprises a plurality of slitter units for cutting traveling strip material into a predetermined configuration of ribbon core materials. The slitter units are arranged in off-set positions in the traveling direction of the strip material, and one of the strip material cut by each of the slitter units is fed upwardly or downwardly rounding about a traveling line, through which the other of the cut strip material is fed. Therefore, guide rollers can be provided upstream and downstream of each of the slitter units, and a width detecting means can be provided for each of the ribbon core materials, so that a plurality of ribbon core materials can be formed in one time with high precision.

Abstract: A cutting apparatus for a strip of a ribbon core comprises a plurality-of slitter units for cutting traveling strip material into a predetermined configuration of ribbon core materials. The slitter units are arranged in off-set positions in the traveling direction of the strip material, and one of the strip material cut by each of the slitter units is fed upwardly or downwardly rounding about a traveling line, through which the other of the cut strip material is fed. Therefore, guide rollers can be provided upstream and downstream of each of the slitter units, and a width detecting means can be provided for each of the ribbon core materials, so that a plurality of ribbon core materials can be formed in one time with high precision.

Abstract: A transformer coil winding apparatus for winding a winding wire on a coil bobbin comprises a rotating drive mechanism for rotatably driving the coil bobbin by a friction force between the coil bobbin and the rotating drive mechanism. Further, the transformer coil winding apparatus comprises a detection unit provided on said coil bobbin, a rotation number counting unit for counting number of rotations of the coil bobbin on the basis of the output of the detection unit, and a drive unit for rotatably driving the rotating drive mechanism in response to the number of rotations on the rotation number counting unit. Therefore, the production cost for the transformer can be lowered.

Abstract: When a material having two straight lines is cut into a plurality of series of strips along a plurality of predetermined curves, one series of strips is in direct contact with another adjacent series of strips.

Abstract: In a power supply apparatus for a load such a toroidal core testing apparatus, an input current is supplied to the load, and an output voltage of the load is obtained. A current corresponding to one part of the output voltage is negatively fed back to the input current.

Abstract: When a material having two straight lines is cut into a plurality of series of strips along a plurality of predetermined curves, one series of strips is in direct contact with another adjacent series of strips.

Abstract: In a power supply apparatus for a load such a toroidal core testing apparatus, an input current is supplied to the load, and an output voltage of the load is obtained. A current corresponding to one part of the output voltage is negatively fed back to the input current.

Abstract: In a wound core to which a cylindrical coil bobbin for windings may be applied, the beginning and/or end portions have a first outer surface with a non-circular elliptic, cross section and a second surface portion on having a circular cross section.

Abstract: In an apparatus for controlling a traverse direction of a running strip, a deviation of the running strip in the traverse direction with respect to a reference position is calculated, and the running strip is moved in the transverse direction in accordance with the deviation, thereby correcting the traverse position of the running strip.

Abstract: When a wound core is manufactured by winding a continuous strip having a desired shape on a winding spool, a thickness of the strip is measured and summed at predetermined periods. The winding operation of the strip on the winding spool is stopped when the summed thickness has reached a predetermined value.