Finish plate assembly for a sprinkler head having interengaging ramp and arm elements

Claim 1

A finish plate assembly for giving a finished appearance to a fire-protection sprinkler head that is exposed through an opening in a room surface such as a suspended ceiling wherein the installed height and angular orientation of said ceiling with respect to a pre-installed sprinkler head is variable, thereby determining a range of variation of relative distances normal to said ceiling between adjacent portions of said opening and said sprinkler head, said assembly comprising: a finish plate member, said member including an exposed exterior surface of sufficient width to extend beyond the periphery of said opening, an interior surface for orientation toward said ceiling, said interior surface including a planar contact surface for engagement with said ceiling outside the periphery of said opening, and two or more arms each having a radially-extending segment; and a receptor fixed to said sprinkler head, said receptor including openings for receiving said arm segments when said finish plate member and arms are moved upward toward said fixed receptor, two or more circumferentially-extensive, resilient ramp elements for attachment around said sprinkler head, and a central opening for receiving said sprinkler head, each of said ramp elements having a top surface defining an upwardly-sloping surface for engaging a bottom surface of one of said radially-extending arm segments and urging said finish plate member upwardly by an increasing amount as said finish plate member is rotated about its axis in relation to said fixed receptor during installation, the upward extent of each said sloping surface being greater than said range of variation, said resilient ramp elements being downwardly deflectable with further rotation of said finish plate member after said contact surface of said finish plate member engages said ceiling, and the resiliency of said ramp elements being selected to maintain contact between said contact surface and said ceiling despite, with passage of time, further variation of said relative distances within said range.