Keyboard device for keyboard musical instrument

A keyboard device for a keyboard musical instrument, comprising:

• keys each opening downward, and having a first side wall, a second side wall, and a front wall, and an abutment portion provided inside said side walls and formed inside of the front wall of said keys, said abutment portion having a lower end located at the same height as lower ends of said side walls, said keys each performing pivotal downward motion when depressed;
• and
• stoppers arranged under said keys in a manner associated therewith, respectively, for abutment of said side walls and said abutment portion of an associated one of said keys thereagainst, thereby stopping the downward pivotal motion of said associated key, said stoppers having a shock-absorbing property,
• wherein said abutment portion is at least one unitary plate-shaped rib continuously extending from the first side wall to the second side wall and having a flat lower surface extending coplanar to a plane including lower end faces of said side walls and wherein the coplanar flat lower surface of the unitary plate-shaped rib includes a largest surface area of the plate-shaped rib, and coming into surface abutment with said stoppers.