Thermostatic control valve system for use in emergency shower and eyewash systems

摘要

A thermally responsive mixing valve assembly is provided that is suitable for use in supplying tempered water to an emergency shower or eyewash system. In one embodiment, the assembly includes a valve body defining hot and cold inlets, hot and cold chambers, a mixing chamber and an outlet. The valve body supports a plurality of thermostatic valves all in fluid communication with the hot and cold liquid chambers and the mixing chamber. Each of the valves includes a thermostat operable to stroke as shuttle valve within a valve liner. The valve liner includes a number of apertures in communication with the cold liquid chamber and a bore in communication with the hot liquid chamber. The shuttle valve modulates within the valve liner to restrict hot water flow through the hot liquid bore, but the flow of cold water through the apertures is unrestricted. The valve liner also includes cold bypass slots that are normally closed by the shuttle valve but that are opened upon a failure of the thermostat. A backseat valve is also provided to terminate hot water flow into the valve on thermostat failure.