초록 ▼

A method and apparatus are provided for operating a small diameter thermal spray gun to thermal spray a coating onto a substrate. A liquid fuel and regeneratively heated air are swirled together within a mixing chamber, passed through a restricter plate orifice, and then passed into the combustion c

A method and apparatus are provided for operating a small diameter thermal spray gun to thermal spray a coating onto a substrate. A liquid fuel and regeneratively heated air are swirled together within a mixing chamber, passed through a restricter plate orifice, and then passed into the combustion chamber to atomize the liquid fuel and mix the liquid fuel with the regeneratively heated air. The liquid fuel is then burned within a combustion chamber of a small diameter thermal spray gun to generate a high energy flow stream, into which a coating material is injected. The combustion chamber includes an inner sleeve with cooling ports which pass cooling air laterally therethrough. A flow nozzle directs the high energy flow stream towards the substrate. The flow nozzle transfers a heat flow from a first portion of the high energy flow stream to a second portion of the high energy flow stream, and provides a thermal barrier to retain heat within the high energy flow stream. The small diameter thermal spray gun may be tuned for operating with a wide variety of coating materials by replacing the combustion chamber inner sleeve and the flow nozzle thermal transfer member with alternative members.

대표청구항 ▼

In a thermal spray gun for coating a substrate with a coating material transported to said substrate in a high energy flowstream, said thermal spray gun having a combustion chamber within which a liquid fuel is burned to generate a high temperature pressurized gas for transporting said coating mater

In a thermal spray gun for coating a substrate with a coating material transported to said substrate in a high energy flowstream, said thermal spray gun having a combustion chamber within which a liquid fuel is burned to generate a high temperature pressurized gas for transporting said coating material to said substrate, a flow nozzle for directing said high temperature pressurized gas towards said substrate, an air flow path through which air is passed interiorly within said thermal spray gun for absorbing heat from said high temperature pressurized gas to preheat said air for combustion with said liquid fuel, a fuel feed port for passing said liquid fuel interiorly into said thermal spray gun to burn within said combustion chamber, and a material injection port for passing said coating material interiorly into said thermal spray gun and mixing with said high temperature pressurized gas to form said high energy flow stream, an improvement comprising: a mixing section for receiving said liquid fuel from said fuel feed port and air from said air flow path, and passing said liquid fuel and said air therein to mix said liquid fuel within said air; an interior periphery of said mixing section having an orifice extending therethrough for passing a combined flow of said air and said liquid fuel from said mixing section to said combustion chamber, said orifice having an internal dimension which is sized for restricting said combined flow to disperse said liquid fuel within said air; and a restricter plate disposed on one end of said mixing section for defining a portion of said interior periphery through which said orifice extends.