Method for removing material from metal workpieces moved relative to the removal tool
AssigneeAdvanced Technik GmbH
InventorsJorg Franke, Wolfgang Schulz, Gerd Herziger
Life of this patent
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Abstract
A method is disclosed for removing material from moving metal workpieces, in particular for cutting sheet metal. It entails preheating, without melting, the surface of the workpiece to a temperature at which ignition is triggered by a combustible gas directed onto the preheated section as a jet under pressure, while burnt material from the workpiece is blown away from the cut recess thus produced. In order to achieve smooth edges on large-gauge workpieces with a relatively high feed-rate, a laser beam is also directed onto the cutting front in the cut recess.
Claims17
A method for removing material from a metal workpiece, comprising the steps of:
- (a) providing a removal tool;
- (b) moving the workpiece relative to the removal tool;
- (c) impinging a laser beam obliquely onto a surface of the workpiece to preheat, without melting, the surface of the workpiece to a temperature at which ignition is triggered by a combustible gas;
- (d) providing a nozzle which is tapered toward the workpiece and which has, at an end thereof, a hole having a ratio of hole length to hole diameter of at least 8:1, the hole also having a cross-sectional area which is smaller than an area of the surface preheated by the laser beam;
- and
- (e) employing the nozzle to blow the combustible gas, as a jet under pressure, onto the surface preheated by the laser beam in a direction perpendicular to the surface.
An apparatus for removing material from a metal workpiece and adapted to be movable relative to the workpiece, comprising:
- nozzle means for directing a combustible gas, which ignites a material of the workpiece at a melting temperature, under pressure in a direction perpendicular to a surface of the workpiece and onto a portion of the surface of the workpiece;
- and
- laser beam guiding means for guiding a laser beam toward the workpiece so as to preheat the portion of the surface of the workpiece to a temperature below the melting temperature;
- wherein said nozzle means is tapered toward the workpiece and is provided, at an end thereof, with a hole having a ratio of hole length to hole diameter of at least 8:1;
- wherein the portion of the surface of the workpiece preheated by the laser beam has an area which is greater than a cross-sectional area of the hole;
- and
- wherein the laser beam is guided by said laser beam guiding means so as to run ahead of said nozzle means and to extend at an angle relative to a longitudinal axis of said nozzle means.
Dependencies are inferred from the claim text.