Patent ID: 6517010
Filing Date: 2003-02-11
Classification: B05B,C23C

Abstract:
A gas injection system for a detonation thermal spray device comprising:a combustion chamber for receiving fuel and an oxidant to generate a combustible mixture and for detonating the combustible mixture to form a wave of hot detonated gas products that propel a powder through a barrel for forming a thermal spray coating; and a set of independent passages, each independent passage having at least one expansion chamber and a plurality of distribution conduits communicated to the expansion chamber for separate feeding of the fuel and oxidant to eliminate combustible mixtures within the set of independent passages and for providing a valve-free open path to the combustion chamber, the set of independent passages having at least one independent passage for the fuel and at least one independent passage for the oxidant, each of the set of independent passages opening to the combustion chamber through a plurality of gas injection openings distributed to facilitate the effective mixing of a combustible mixture prior to its ignition in each detonation cycle; and the set of independent passages providing a cooling path for a portion of the wave of the hot detonated gas products received from the combustion chamber after each ignition and detonation of the combustible mixture to form a cooled volume of detonated gas products and then being for injecting the cooled detonated gas products ahead of additional fuel and additional oxidant into the combustion chamber with the cooled volume of detonated gas products forming a gaseous thermal barrier between the hot detonated gas products remaining in the combustion chamber after each ignition and detonation of the subsequent combustible mixture formed from the additional fuel and additional oxidant injected into the combustion chamber that mix and ignite to generate and repeat the detonation cycle.