DETERMINATED QUANTITY FEED DETECTING METHOD FOR POWDER MATERIAL

摘要

PURPOSE:To detect abnormality accurately and easily, by comparing a referential aging variation of gas pressure with an aging variation of gas pressure during actual supply of gas. CONSTITUTION:Metallic powder 4 in a hopper 5 passes through a receiving member 10, a joint 13 and a pipe 14 then discharged into a plasma arc and fed to a refusing portion of a cam shaft 18. A pressure gauge 20 for detecting pressure in an enclosed box 1 through a piping 19 is fixed to the enclosed box 1, and a measurement of said pressure gauge 20 is inputted through an A/D converter 21 to an arithmetic unit 22. The quantity of the metallic powder 4 being fed through the pipe 14 has a correlation with the variation of gas pressure in the enclosed box 1, and said correlation can be represented as waveform. Here, a waveform when proper quantity of metallic powder is fed by fixed quantity is stored as a normal waveform into the arithmetic unit 22. Consequently, the quantity of metallic powder 4 being fed can be calculated based on the waveform.