Gas cutting torch for interchangeable tips

Claim 2

A gas torch comprising a mixer assembly and a plurality of interchangeable torch tips joined in a metal-to-metal seal provided by a convexly coned nose end of said mixer assembly and a concavely coned end of each tip, each coned end having two corresponding frustoconical portions separated by an annular recess, said mixer having a plurality of fuel gas passages leading into said recess and said tip having fuel gas passage means leading from said recess to an outer end of said tip, said mixer assembly having a central axial passageway for high-pressure oxygen at its said nose end and each said tip having a mating central axial passageway and a recess surrounded by one of said frustoconical portions to receive said nose end.

Claim 3

A gas torch, including in combination: a torch head body having a recess and three gas passages leading into said recess at different locations, comprising a first gas passage for preheat low-pressure oxygen, a second gas passage for fuel gas, and a third gas passage for high-pressure oxygen, a mixer assembly in said recess having mixing means connected to said first and second passages for mixing said fuel gas with said low-pressure oxygen and having a generally conical projecting outer nose end with two frustoconical surface portions of the same cone separated by an annular recess having an annular shoulder through which extend a plurality of passages for the mixture of fuel gas and low-pressure oxygen, said passages being connected to said mixing means, said mixer assembly also having a conduit for said high-pressure oxygen with an inlet portion connected to said third gas passage, and an axial central outlet at the extremity of said nose end and lying along the axis of the frustoconical portions, a torch tip having an inlet end abutting said nose end and an outlet end and having a central axial conduit in line with said axial central outlet of said mixer assembly and extending the full length of said tip, for said high-pressure oxygen, said inlet end having a generally conical recess providing two frustoconical portions which mate with the frustoconical portions of said mixer assembly and providing with them a metal-to-metal seal between the conduits for the high-pressure oxygen and the passages for the mixture of said fuel gas and low-pressure oxygen and on both sides of said shoulder, said two frustoconical portions being separated by an annular recess cooperating with the annular recess of said mixer assembly to provide an annular chamber for reception of the mixture of fuel gas and low-pressure oxygen, said torch tip also having passage means leading from said annular recess at said inlet end to the outer end of the tip, and means for holding said torch tip and said mixer assembly together to maintain said metal-to-metal seal.

Claim 4

A gas torch, including in combination: a torch head body having a recess and three gas passages leading into said recess at different locations, comprising a first gas passage for preheat low-pressure oxygen, a second gas passage for fuel gas, and a third gas passage for high-pressure oxygen, a mixer assembly in said recess having mixing means connected to said first and second passages for mixing said fuel gas with said low-pressure oxygen and having a generally conical projecting outer nose end with two frustoconical surface portions of the same cone separated by an annular recess having an annular shoulder through which extend a plurality of passages for the mixture of fuel gas and low-pressure oxygen, said passages being connected to said mixing means, said mixer assembly also having a conduit for said high-pressure oxygen with an inlet portion connected to said third gas passage, and an axial central outlet at the extremity of said nose end and lying along the axis of the frustoconical portions, a torch tip having an inlet end abutting said nose end and an outlet end and having a central axial conduit in line with said axial central outlet of said mixer assembly and extending the full length of said tip, for said high-pressure oxygen, said inlet end having a generally conical recess providing two frustoconical portions which mate with the frustoconical portions of said mixer assembly and providing with them a metal-to-metal seal between the conduits for the high-pressure oxygen and the passages for the mixture of said fuel gas and low-pressure oxygen and on both sides of said shoulder, said two frustoconical portions being separated by an annular recess cooperating with the annular recess of said mixer assembly to provide an annular chamber for reception of the mixture of fuel gas and low-pressure oxygen, said torch tip also having passage means leading from said annular recess at said inlet end to the outer end of the tip, and means for holding said torch tip and said mixer assembly together to maintain said metal-to-metal seal.

Claim 5

The gas torch of claim 2 wherein said means for holding said torch tip and said mixer assembly together comprises an annular step on the torch tip and a correspondingly stepped tubular nut that is threaded into said body.

Claim 6

The gas torch of claim 2 wherein said body is provided with a step on the outer side of said third gas passage provided with a sharp undercut to define a downwardly projecting annular spur and said mixer assembly has a radial step at the inner end of which is an annular flaring recess engaging said spur, so that tightening of said mixer assembly into said body forces said spur to swage out into said flaring recess and provide a metal-to-metal seal preventing leakage of said high-pressure oxygen.