Flush valve

摘要

Described here are flush valves for delivering a selected amount of water from a toilet tank into a toilet bowl, particularly collapsible flush valves having substantial durability and resistance to wear and deleterious chemicals. These flush valves have a collapsible member extending from above the surface of the water in the toilet tank to the tank outlet in the normal (closed flush valve) state. Collapsing the flush valve allows water to flow into the toilet bowl through the flush valve until the toilet tank is drained to the level of the collapsed flush valve and buoyancy is restored. Flush valves may be made of a material that does not substantially deteriorate in the presence of halogen-containing toilet disinfectants, and the outer surface (the water contacting surface) of the flush valves may be a single continuous piece.