Abstract: A hinge assembly (20) having a generally horizontal pivot axis (40), the assembly (20) including: a lower hinge member (21), said lower member (21) having a longitudinal recess (24) providing said axis (40) and a projection (25) extending longitudinally parallel to said axis (40), the projection (25) having a longitudinal substantially arcuate surface (26) spaced from said axis (40) by a fixed radius; and an upper hinge member (31), said upper member (31) having a pivot portion (35) located in said recess (24) so that the members (21, 31) can pivot relative to each other about said axis (40), the upper hinge member (31) further having a cavity (38) into which said projection (25) extends and moves, said cavity (38) having an entrance portion (39) located at a fixed radius relative to said axis (40) and extending longitudinally parallel to said axis (40), the entrance portion (39) being located adjacent said substantially arcuate surface (26) of said lower member (21).