Patent ID: 8359709

Claim:
A hinge assembly, comprising: a first hinge member having a leaf portion and a lower sleeve, said lower sleeve having an upper cylindrical passage with a first diameter and a lower cylindrical passage axially disposed immediately under said upper cylindrical passage and having a second diameter smaller than that of said upper cylindrical passage, said lower cylindrical passage having an interior wall with a surface topography; a second hinge member having a leaf portion and an upper sleeve, said upper sleeve including an upper female portion and a lower male element extending axially downwardly from said female portion and having an outer diameter sized to fit into the opening of said upper cylindrical passage of said lower sleeve so as to provide a pivotal connection between said first and second hinge members, wherein said male element includes a lower portion having an interior wall configured substantially identically to that of said interior wall of said lower cylindrical passage of said lower sleeve, and wherein said upper sleeve includes a recess at its upper end, having a first diameter, and a cylindrical through hole having a second diameter, such that when said male element of said upper sleeve is inserted into said lower sleeve, said through hole is axially aligned with said upper cylindrical passage and said lower cylindrical passage of said lower sleeve; a hinge pin inserted into said upper cylindrical passage and said lower cylindrical passage, said hinge pin including an upper end, a lower end, a lower portion having an outer surface including a surface topography that cooperates with the surface topography of said interior wall of said lower sleeve; wherein when said hinge pin is pushed up into a locked position, said first hinge members are prevented from rotating in relation to one another, and wherein when said hinge pin is pushed down into an unlocked position, no portion of said hinge pin outer surface engages said interior wall of said male element to prevent pivotal rotation of said hinge assembly.