Patent ID: 7712274

Claim:
A suspended ceiling system comprising grid runners and downwardly accessible generally planar tiles mounted on the grid runners, the tiles being rectangular in plan view with four peripheral edges, the peripheral edges each having portions that extend horizontally underneath an adjacent grid runner, each edge of an oppositely disposed pair of said edges having a groove with a downwardly facing support surface and an associated one of the underneath extending portions disposed between a plane of a lower visible face of the tile and a plane of an upper back face of the tile, the grid runners each being symmetrical about a vertical mid-plane and having horizontal flange portions extending in opposite directions away from said mid-plane, each of said oppositely disposed edges of said tiles having a generally vertical abutment surface above its support surface, the support surface resting on the adjacent horizontal flange portion, the runners having locating surfaces of limited height rising above said flange portions and engageable with the abutment surfaces, the abutment surfaces being free of portions of the tile that lie above the abutment surfaces in an installed orientation of the tile, the grooves having a height at least equal to the combined height of the flange and a locating surface so that the flange and locating surface can be received in a groove when one of the opposed tile edges is lifted and its abutment surface is raised above an adjacent locating surface and the tile can thereafter be shifted towards the runner adjacent the lifted edge a distance sufficient to allow the opposite edge to drop below the flange portion of its associated runner.