Abstract: A steering-wheel core eliminating or reducing the need to perform finishing processing after casting and decreasing a manufacturing cost even when the steering-wheel core is cast using a molten metal process. The steering wheel core includes a boss core portion coupled to a steering shaft, a rim core portion and a spoke core portion. The boss core portion forms a nut seat surface that makes contact with a nut when the nut is fastened to a distal end of the steering shaft. A recess is formed in the nut seat surface depressed toward a back surface side of the boss core portion. The recess is preferably provided in an annular form so as to surround the circumference of the nut seat surface.

Abstract: A steering-wheel core eliminating or reducing the need to perform finishing processing after casting and decreasing a manufacturing cost even when the steering-wheel core is cast using a molten metal process. The steering wheel core includes a boss core portion coupled to a steering shaft, a rim core portion and a spoke core portion. The boss core portion forms a nut seat surface that makes contact with a nut when the nut is fastened to a distal end of the steering shaft. A recess is formed in the nut seat surface depressed toward a back surface side of the boss core portion. The recess is preferably provided in an annular form so as to surround the circumference of the nut seat surface.

Abstract: A steering-wheel core and a method for casting the same capable of eliminating the need to perform finishing processing after casting and decreasing manufacturing cost even when the steering-wheel core is cast using a molten metal. The method for casting a steering-wheel core (100) includes: providing a protruding portion (92) in a surface (91) of an inner surface of a casting die (90), with the surface defining a nut seat surface; and causing a molten metal to hit on the protruding portion (92) when the molten metal flows into the casting die (90) such that a change occurs in the flowing direction of the molten metal flowing toward the surface (91) that defines the nut seat surface.

Abstract: A steering-wheel core and a method for casting the same capable of eliminating the need to perform finishing processing after casting and decreasing a manufacturing cost even when the steering-wheel core is cast using a molten metal are provided. The method for casting a steering-wheel core (100) according to the present invention includes: providing a protruding portion (92) in a surface (91) of an inner surface of a casting die (90), with the surface defining a nut seat surface; and causing a molten metal to hit on the protruding portion (92) when the molten metal is flown into the casting die (90) such that a flowing direction of the molten metal flowing toward the surface (91 that defines the nut seat surface is changed.