Importance

Loading Importance Indicators...

Abstract

A single cathode plasma gun injects powder therein so that the powder exits along a central axis of an exit barrel of the gun, in order to provide improved coatings of the powder material on a workpiece. The central axis of the single cathode extends from an arc chamber and intersects with the central axis of the exit barrel so as to form an acute angle which is substantially greater than 0.degree. but no greater than 90.degree.. Examples of the acute angle include 45.degree. and 10.degree.. A powder feed passage extends along an axis which may be coincident with the central axis of the exit barrel or may form an angle with the central axis of the exit barrel of as much as 45.degree.. Consequently, the axis of the powder feed passage forms an angle with the central axis of the single cathode which is at least as great as the acute angle between the central axes of the single cathode and the exit barrel. Existing plasma guns can be retrofitted with a new anode attachment to achieve desired angles of plasma flow and powder delivery. Where the central axis of the single cathode forms an acute angle with the central axis of the exit barrel, the resulting bend in the passage extending from the arc chamber below the single cathode is disposed adjacent an entry end of the exit barrel, and the powder feed passage terminates adjacent such bend. Alternatively, the powder can be introduced into the middle of the plasma stream at the entry end of the exit barrel by a powder injector extending into the exit barrel from the wall of the passage. The single cathode can be axially adjusted to move the charged plasma region adjacent the termination of the powder feed passage, for more effective heating of the powder. The angles formed by the central axes of the single cathode and the powder feed passage relative to the central axis of the exit barrel can be adjusted relative to each other so that the injected powder is deflected along the central axis of the exit barrel, again providing for an improved coating of the powder material on a workpiece.

Loading the Abstract Image...

First Claim