Thermal spray apparatus for coating a substrate with molten fluent material

DETAILED DESCRIPTION What is claimed is: 1.
Thermal spray apparatus for providing a stream of molten heat fusible fluent material for coating a substrate, comprising: heat source means including a flame for producing a stream of heated gas heated to sufficiently high temperature to melt said material; material advancing means for advancing a stream of heat fusible fluent material into said stream of heated gas to melt said material and produce said stream of molten fluent material; and flame barrier means intermediate said flame and said stream of molten fluent material, said flame barrier means for permitting passage therethrough of said stream of heated gas and for preventing reaction between said flame and said material.
2.
Thermal spray apparatus according to claim 1 further including housing means surrounding said heat source means, said material advancing means and said flame barrier means and for confining said stream of heated gas to facilitate transfer of heat from said stream of heated gas to said stream of heat fusible fluent material to melt said material.
3.
Thermal spray apparatus according to claim 2 wherein said material advancing means comprise material feed tube means extending through said heat source means, said flame barrier means and partially through said housing means and wherein said flame barrier means is for preventing reaction between said flame and said material upon said material exiting said feed tube means.
4.
Thermal spray apparatus according to claim 3 wherein said feed tube means comprise concentric inner and outer tubes spaced apart and separted by an air space to prevent melting of said stream of heat fusible fluent material within said feed tube means, said stream of heat fusible fluent material passing through the inner tube.
5.
Thermal spray apparatus according to claim 4 wherein said apparatus further includes heat capacitor means for storing heat for enhancing producing of said stream of heated gas, and wherein said material feed tube means also extends through said heat capacitor means