| United States Patent | 5,847,358 |
| Franke, et. al. | Dec. 8, 1998 |
Abstract
A method is disclosed for removing material from moving metal workpieces, 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.
| Inventors: | Franke; Jorg (Herzogenrath, DE); Schulz; Wolfgang (Langerwehe, DE); Herziger; Gerd (Roetgen-Rott, DE). |
| Assignee: | Advanced Technik GmbH (Steinenbronn, DE); Fraunhofer-Gesellschaft zur Forderung der Angewandten Forschung E.V. (Munchen, DE). |
| Appl. No.: | 672,871 |
| Filed: | Jun. 28, 1996 |
| Continuation of (including streamline cont.) Ser. No. 240,661, May 18, 1994, Pat. No. 5,651,904. |
| Nov. 19, 1991 [DE] | 41 38 075.4 |
| May 12, 1992 [DE] | 42 15 561.4 |
| Intl. Cl. : | B23K 26/06, B23K 26/14 |
| Current U.S. Cl.: | 219/121.67; 219/121.72; 219/121.73; 219/121.75; 219/121.84 |
| Field of Search: | 219/121.67, 121.72, 121.73, 121.76, 121.77, 121.84, 121.61, 121.75, 121.74 |
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