Nib for writing instrument

Claim 1

A nib structure for a writing instrument comprising a core member having three legs radially extending from the center of said core member, said egs having substantially equal thickness and extending from said center with substantially equal angles, three pairs of subcore elements, each of said subcore elements being solid and substantially triangular shaped in section and having a groove or grooves formed on each triAngular side along the longitudinal direction thereof so that each side of the triangular sides of the same subcore element has the same surface shape, and a tubular shroud enclosing outer peripheral surfaces of said legs and said subcore elements, except, at least at the sharpened writing tip portion thereof, said tubular shroud holding said subcore elements to said core member to provide capillary ink feeding channels between said tubular shroud and said grooved outer peripheral surface of said subcore elements, wherein said subcore elements of each pair are snugly disposed side by side between adjoining legs of said core member with capillary ink feeding channels between said legs and the grooved surface of said subcore elements and between the grooved surfaces of said pair of subcore elements, said each pair of subcore elements are constructed with two subcore elements with different shaped surfaces from each other, and each of said legs has a thickness of 0.05 to 0.3 mm and a length of 0.1 to 1.0 mm.