A laminated iron core includes a plurality of blanked iron core pieces laminated together, a continuity of side parts of the iron core pieces configuring a side surface of the laminated iron core. The side part of each iron core piece includes a specific light reflection area having a prescribed width along a circumferential direction, where the specific light reflection area has different light reflection characteristics from the other area of the side part of the iron core piece, and a striped pattern, configured by the specific light reflection areas, exists on the side surface of the laminated iron core.

A notching device includes a base, a stand, a lever assembly, and a notching assembly. The base and stand are coupled together. The lever assembly is coupled to the stand and the notching assembly. The notching assembly includes a die set. The die set has a two-tier upper shoe and a lower shoe. The two-tier show has a first tier and a second tier separated by a gap and the lower shoe includes a notch. The two-tier upper shoe fits within the lower shoe.

A notching device includes a base, a stand, a lever assembly, and a notching assembly. The base and stand are coupled together. The lever assembly is coupled to the stand and the notching assembly. The notching assembly includes a die set. The die set has a two-tier upper shoe and a lower shoe. The two-tier show has a first tier and a second tier separated by a gap and the lower shoe includes a notch. The two-tier upper shoe fits within the lower shoe.

There is provided a non-oriented electrical steel sheet having a predetermined chemical composition, in which an area fraction of a crystal structure A composed of crystal grains having a grain size of 100 ?m or more is 1% to 30% in a cross section parallel to a rolled plane of the non-oriented electrical steel sheet, an average grain size of a crystal structure B which is a crystal structure other than the crystal structure A is 40 ?m or less, and a Vickers hardness HvA of the crystal structure A and a Vickers hardness HvB of the crystal structure B satisfy Equation 1 ((HvA.sup.2+HvB.sup.2)/2?(HvA+HvB).sup.2/4?7.0).

Disclosed is a processing apparatus for rounding an edge of a lead tab for a secondary battery, comprising: a loading unit on which the lead tab manufactured by the lead tab manufacturing apparatus is loaded and seated; a primary edge processing unit installed at a downstream side of the loading unit; a secondary edge processing unit installed at a downstream side of the primary edge processing unit; an unloading unit installed at a downstream side of the secondary edge processing unit and configured to load the lead tab transferred from the secondary edge processing unit and discharge the loaded lead tab to the outside; and a transfer unit configured to load the lead tab.

Disclosed is a processing apparatus for rounding an edge of a lead tab for a secondary battery, comprising: a loading unit on which the lead tab manufactured by the lead tab manufacturing apparatus is loaded and seated; a primary edge processing unit installed at a downstream side of the loading unit; a secondary edge processing unit installed at a downstream side of the primary edge processing unit; an unloading unit installed at a downstream side of the secondary edge processing unit and configured to load the lead tab transferred from the secondary edge processing unit and discharge the loaded lead tab to the outside; and a transfer unit configured to load the lead tab.

A notching tool for notching a workpiece, the notching tool having a notching punch and a die having an inner surface. The notching punch includes first and second punch portions, the first punch portion has a punch plane intended to hit the workpiece in a notching operation. The second punch portion protrudes from the punch plane in a direction which is substantially perpendicular to the punch plane, and is intended to contact the inner surface of the die when the notching punch hits the workpiece. The disclosure further provides a use of this notching tool and a method of notching which involves the operation of such a notching tool.

A notching tool for notching a workpiece, the notching tool having a notching punch and a die having an inner surface. The notching punch includes first and second punch portions, the first punch portion has a punch plane intended to hit the workpiece in a notching operation. The second punch portion protrudes from the punch plane in a direction which is substantially perpendicular to the punch plane, and is intended to contact the inner surface of the die when the notching punch hits the workpiece. The disclosure further provides a use of this notching tool and a method of notching which involves the operation of such a notching tool.

A method of manufacturing a stator is provided. The method may include stamping steel into laminations each having an inner edge area defining a residual stress associated with a magnetic permeability. The method may also include exposing the laminations to a changing magnetic field such that, for each of the laminations, a density of resulting eddy currents is greatest near the inner edge area to heat the same relative to central areas of the lamination to decrease the residual stress and core loss.

A method of manufacturing a stator is provided. The method may include stamping steel into laminations each having an inner edge area defining a residual stress associated with a magnetic permeability. The method may also include exposing the laminations to a changing magnetic field such that, for each of the laminations, a density of resulting eddy currents is greatest near the inner edge area to heat the same relative to central areas of the lamination to decrease the residual stress and core loss.