Mixing valve

#This invention relates to a mixing valve for supplying fluid to a fluid outlet.

#Mixing valves can be used to supply tempered, e.g., tepid, water to a water outlet. In some embodiments, cold water from a supply source flows to a cold water inlet, and hot water from a supply source flows to a hot water inlet of the mixing valve. The cold and hot water are mixed in the valve, and mixed, tempered water is directed through a tempered water outlet.

#The mixing valves can be used in commercial and/or industrial applications such as, for example, in emergency drench showers and eyewash stations. The tempered water allows a user to rinse relatively comfortably for an adequate amount of time.

#FIG. 1 is a cross sectional view of an embodiment of a mixing valve.

#FIG. 2 is an exploded perspective view of the mixing valve of FIG. 1.

#FIG. 3A is a top view of a bottom housing of the mixing valve of FIG. 1; FIG. 3B is a cross sectional view of the bottom housing of FIG. 3A, taken along line 3B-3B; FIG. 3C is a side view of the bottom housing of FIG. 3A, taken along line 3C-3C; FIG. 3D is a cross sectional view of the bottom housing of FIG. 3B, taken along line 3D-3D; FIG. 3E is a cross sectional view of the bottom housing of FIG. 3B, taken along line 3E-3E; FIG. 3F is a cross sectional view of the bottom housing of FIG. 3E, taken along line 3F-3F; and FIG. 3G a cross sectional view of the bottom housing of FIG. 3E, taken along line 3G-3G.

#Referring to FIGS. 1 and 2, a mixing valve 20 includes a manifold 21 formed of a bottom cap 22, a bottom housing 24 connected to the bottom cap by a threaded connection 23, a top housing 26 connected to the bottom housing by screws 25, and an etched bonnet 28 connected to the top housing by screws 27. Bottom housing 24 defines a cold water inlet 30 and a hot water inlet 32 through which cold and hot water, respectively, are delivered into valve 20. Top housing 26 defines a mixing chamber 36 and a water outlet 34. Located within mixing chamber 36 is a temperature-responsive device 38 that, under normal operation, regulates flow of hot and cold water to mixing chamber 36.

#In general, mixing valve 20 can be used to deliver tempered water, no water, or cold water, for example, to an emergency drench shower or an eyewash fountain. Under normal operation, cold water enters cold water inlet 30, hot water enters hot water inlet 32, and the two fluids mix in valve 20 such that tempered water of a predetermined maximum temperature is delivered through outlet 34. In the event that cold water is not supplied to inlet 30 (e.g., cold water supply failure), mixing valve 20 shuts off the flow of hot water through outlet 34, thereby reducing the risk of scalding or bums from the hot water. In the event that hot water is not supplied to inlet 32 (e.g., hot water supply failure) or temperature-responsive device 38 fails, mixing valve 20 is capable of continuing to supply cold water to outlet 34. As described below, mixing valve 20 includes a dual by-pass mechanism 29 that includes a pressure sensing by-pass and a temperature sensing by-pass. In the event that valve 20 cannot deliver tempered fluid, the dual by-pass mechanism provides the valve with a redundant system to deliver cold water to a user.

#Bottom housing 24 includes a manifold 31 (e.g., cast from bronze) for directing cold and hot water to mixing chamber 36. Referring to FIGS. 1 and 3A-3G, cold water inlet 30 is in fluid communication with a cold water cavity 40, and hot water inlet 32 is in fluid communication with a hot water cavity 42. Cold water cavity 40 is in fluid communication with a bottom cavity 44 (FIG. 3B), which in turn is in fluid communication with a front cavity 46 and a back cavity 48 (FIG. 3E). Front and back cavities 46 and 48 lead to a top cavity 50 that is in fluid communication with mixing chamber 36 (FIGS. 1 and 3E). Cold water cavity 40 is also in fluid communication with a center cavity 54 (FIG. 3B). Like bottom cavity 44, center cavity 54 is also in fluid communication with front and back cavities 46 and 48, and thus also with top cavity 50 and mixing chamber 36 (FIGS. 1 and 3E).