Gas mixer for cutting torches

In a gas torch head having a tip end for attaching a tip thereto, mixing means for delivering a mixture of fuel gas and oxygen to said tip, fuel gas passageway means for delivering a fuel gas to said mixing means, and oxygen passageway means for delivering oxygen to said mixing means, the improvement comprising:

• said mixing means comprising a bore extending into said head from said tip end and having an axis and an inner end axially spaced from said tip end, said fuel gas passageway means and said oxygen passageway means opening into said bore at axially spaced locations, an insert in said bore coaxial therewith and having an outlet end facing said tip end, outlet passageway means extending axially into said insert from said outlet end, and a mixing recess in said insert in flow communication with said outlet passageway means and in flow communication with said bore between said locations, said bore having an inner surface and said insert having an outer surface facing said inner surface, said mixing recess having an inlet end opening into said outer surface, said fuel gas passageway means and said oxygen passageway means opening through said inner surface at said bore, said inner and outer surfaces being radially spaced apart between said inlet end and said fuel gas passageway means to provide a fuel gas metering passage and between said inlet end and said oxygen passageway means to provide an oxygen metering passage for respectively metering flow of fuel gas and oxygen to said mixing recess from the corresponding one of said fuel gas passageway means and oxygen passageway means.

In a gas torch head having a tip end for attaching a tip thereto, mixing means for delivering a mixture of fuel gas and oxygen to said tip, fuel gas passageway means for delivering a fuel gas to said mixing means, and oxygen passageway means for delivering oxygen to said mixing means, the improvement comprising:

• said mixing means comprising a circular bore extending into said head from said tip end and having an axis and an inner end axially spaced from said tip end, a circular gas mixing insert in said bore coaxial therewith and having an axially inner end in radially sealing interengagement with said inner end of said bore and having an outlet end in radially sealing interengagement with said bore intermediate said inner end thereof and said tip end of said head, said outlet end of said insert including an end wall facing said tip end, said insert having an outer surface between said inner and outlet ends and a radially outwardly open annular gas mixing recess in a portion of said outer surface, said bore including surface portions on axially opposite sides of said recess and radially spaced from said outer surface portion of said insert to provide first and second annular gas metering passages in flow communication with said gas mixing recess, said fuel gas passageway means opening radially into said bore for delivering fuel gas to said mixing recess through said first metering passage, said oxygen passageway means opening radially into said bore for delivering oxygen to said mixing recess through said second metering passage, and a plurality of outlet passages in said insert extending from said mixing recess through said end wall thereof for delivering a mixture of said fuel gas and oxygen from said mixing recess to said outlet end of said insert.