Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
174 words
A process for rendering visible defects occurring at the surface of workpieces, said process including the steps of magnetizing the workpiece by passing a direct electric current therethrough at a magnetization path whereby stray flux lines of the magnetic field are caused to develop at defect locations of the workpiece; applying a ferritic powder to at least a portion of the surface of the workpiece whereby the powder is attracted by the stray flux lines and accumulates at the region of the deflect locations thereby rendering such defect locations visible; covering the surface of the workpiece which has had applied thereto the powder and at least the immediately surrounding regions of the workpiece with a marking material, then removing the powder to leave a marked outline of the defect location which was previously covered by the powder, to thereby fix the position of the defect location. CM,2Ocess as defined in claim 1, wherein the ferritic powder is sprayed onto the surface of the workpiece and comprises agglomerated particles of both ferritic and nonferritic sUbstances.
Claim 2
Dependent Claim
25 words
A process as defined in claim 1, wherein the ferritic powder is sprayed onto the surface of the workpiece and comprises substantially even granular sizes.
Claim 3
Dependent Claim
37 words
A process as defined in claim 1, wherein the powder at a defect location is removed by directing an airstream against the workpiece, and wherein the marking material surrounding the defect location is dried by the airstream.
Claim 4
Dependent Claim
24 words
A process as defined in claim 1, further including the step of covering the entire surface area of the workpiece with the marking material.
Claim 5
Independent Claim
173 words
An apparatus for detecting defect locations in the surface of a workpiece, said apparatus comprising: at least a pair of current carrying electrode units disposed in contact with the workpiece for passing a direct electric current therethrough at a magnetization path defined by said electrode units whereby stray flux lines of the magnetic field result at surface defect locations of the workpiece; spraying nozzle means for spraying ferritic particles evenly over the surface of the workpiece, said ferritic particles being attracted by the stray flux lines and accumulating at defect locations thereby rendering visible the surface defect locations; and means for fixing the visible indication of the surface defect locations to maintain such defect locations visible, said fixing means comprising a color marking material spraying means for spraying color marking material over the powder on the surface of the workpiece and onto at least the immediately surrounding regions of the workpiece surface, said color marking material spraying means being disposed between said pair of electrode units within the magnetization path of the workpiece.
Claim 6
Independent Claim
173 words
An apparatus for detecting defect locations in the surface of a workpiece, said apparatus comprising: at least a pair of current carrying electrode units disposed in contact with the workpiece for passing a direct electric current therethrough at a magnetization path defined by said electrode units whereby stray flux lines of the magnetic field result at surface defect locations of the workpiece; spraying nozzle means for spraying ferritic particles evenly over the surface of the workpiece, said ferritic particles being attracted by the stray flux lines and accumulating at defect locations thereby rendering visible the surface defect locations; and means for fixing the visible indication of the surface defect locations to maintain such defect locations visible, said fixing means comprising a color marking material spraying means for spraying color marking material over the powder on the surface of the workpiece and onto at least the immediately surrounding regions of the workpiece surface, said color marking material spraying means being disposed between said pair of electrode units within the magnetization path of the workpiece.
Claim 7
Dependent Claim
45 words
An apparatus as defined in claim 6, further including a defect position-finding device disposed between said spray nozzle means and said color marking material spraying means, said defect position-finding device determining the presence of a defect location and actuating said color marking material spraying means.
Claim 8
Dependent Claim
58 words
An apparatus as defined in claim 6, further including means for establishing a feed velocity of the workpiece with respect to said apparatus, and wherein one of said pair of electrode units at the discharge end of said apparatus comprises workpiece contact means disposed on an endless chain driven in synchronism with the feed speed of the workpiece.