Patent ID: 7178791

Claim:
A staircase assembly for use in a preassembled adjustable staircase system, comprising a baluster having a central axis, a rail portion and a hinge assembly for adjustably attaching an upper end of the baluster pivotally to the rail portion, the upper end of the baluster having a substantially uniform cross-sectional shape along a plane perpendicular to the axis of the baluster and the rail portion having an underside formed with an opening recessed interiorly into the underside of the rail portion, the hinge assembly comprising: a pair of half-caps each having a lateral face and an adjacent face, each half-cap having a recess formed in the lateral face, the recess including an opening extending through the adjacent face; the pair of half-caps being mateable with their respective lateral faces in opposed facing relation to form a cap assembly configured for receipt fully enclosed within the recessed opening of the rail portion without projecting outwardly beyond the underside of the rail portion; wherein the respective recesses of the half-caps when mated to form the cap assembly form a receiving area therein for completely enclosing the upper end of the baluster; a pin for connecting the end of the baluster rotationally to the cap assembly within the receiving area for relative pivotal movement about a pin axis; wherein the respective openings of the half-caps when mated to form the cap assembly form an elongated mouth therein defining a range of available pivotal movement of the baluster relative to the cap assembly and to the rail portion in correspondence to a range of selectable rake angles of the rail portion in the staircase system, wherein the hinge assembly is completely hidden within the rail portion without projecting outwardly beyond the underside of the rail portion to give the staircase assembly the appearance of a custom, site-built staircase assembly.