Claims
- 1. A method for determining a heating line in the bending of a steel plate, comprising:determining the number of a plurality of congruent isosceles triangles, which are connected together while sharing their equal sides, on the basis of the radius of a curve of a target shape of the steel plate to be bent, the radius of a curve of a measured shape of the steel plate, and a separately set bending angle of the steel plate so that when the curve of the target shape of the steel plate is regarded as an arc, the arc of the target shape of the steel plate can be approximated by a fold line defined by the bases of the plural congruent isosceles triangles and that when the curve of the measured shape of the steel plate is regarded as an arc, the arc of the measured shape of the steel plate can be approximated by a fold line defined by the bases of a plurality of other congruent isosceles triangles which are connected together while sharing their equal sides, the number of the latter isosceles triangles being the same as the number of the former isosceles triangles whose bases constitute the approximating fold line for the target shape; dividing the arc of the measured shape by the number of the isosceles triangles to form respective points on the arc; using the respective points as heating points; drawing straight lines from a certain heating point on a certain arc, as a starting point, to heating points on other arcs on the basis of the heating points that have been so determined; examining the degree of parallelism between each of the straight lines and a reference line that is a straight line showing the direction of a central axis of a cylinder provided that the target shape is approximately deemed as a part of the cylinder; if this degree of parallelism is within a predetermined range, performing grouping of the relevant heating points as the heating points of the same group; and connecting the respective heating points of the same group by a straight line or a curve to determine a heating line.
- 2. A method for determining a heating line in the bending of a steel plate, comprising:dividing a curve of a target shape of the steel plate to be bent, into a plurality of successive segments; similarly dividing a curve of a measured shape of the steel plate into a plurality of successive segments in correspondence with the curve of the target shape; determining the number of a plurality of congruent isosceles triangles, which are connected together while sharing their equal sides, for each segment on the basis of the radius of a division of the curve in each segment of the target shape of the steel plate, the radius of a division of the curve in each segment of the measured shape of the steel plate, and a separately set bending angle of the steel plate so that when the division of the curve in each segment of the target shape of the steel plate is regarded as an arc, the arc in each segment of the target shape of the steel plate can be approximated by a fold line defined by the bases of the plural congruent isosceles triangles and that when the division of the curve in each segment of the measured shape of the steel plate is regarded as an arc, the arc in each segment of the measured shape of the steel plate can be approximated by a fold line defined by the bases of a plurality of other congruent isosceles triangles which are connected together while sharing their equal sides, the number of the latter isosceles triangles being the same as the number of the former isosceles triangles whose bases constitute the approximating fold line for the target shape; dividing the arc of the measured shape in each segment by the number of the isosceles triangles to form respective points on the arc; using the respective points as heating points; drawing straight lines from a certain heating point on a certain arc, as a starting point, to heating points on other arcs on the basis of the heating points that have been so determined; examining the degree of parallelism between each of the straight lines and a reference line that is a straight line showing the direction of a central axis of a cylinder provided that the target shape is approximately deemed as a part of the cylinder; if this degree of parallelism is within a predetermined range, performing grouping of the relevant heating points as the heating points of the same group; and connecting the respective heating points of the same group by a straight line or a curve to determine a heating line.
- 3. A system for determining a heating line in the bending of a steel plate, comprising:a heating point determining unit which reads in target shape data on a target shape of a steel plate to be bent, and steel plate shape measurement data to be obtained by measuring a surface shape of the steel plate; determines the number of a plurality of congruent isosceles triangles, which are connected together while sharing their equal sides, on the basis of the radius of a curve of the target shape of the steel plate, the radius of a curve of the measured shape of the steel plate, and a separately set bending angle of the steel plate so that when the curve of the target shape of the steel plate is regarded as an arc, the arc of the target shape of the steel plate can be approximated by a fold line defined by the bases of the plural congruent isosceles triangles and that when the curve of the measured shape of the steel plate is regarded as an arc, the arc of the measured shape of the steel plate can be approximated by a fold line defined by the bases of a plurality of other congruent isosceles triangles which are connected together while sharing their equal sides, the number of the latter isosceles triangles being the same as the number of the former isosceles triangles whose bases constitute the approximating fold line for the target shape; divides the arc of the measured shape by the number of the isosceles triangles to form respective points on the arc; and calculates the coordinates of the respective points as heating points; and a heating line determining unit which reads in data on the heating points calculated by the heating point determining unit; draws straight lines from a certain heating point on a certain arc, as a starting point, to heating points on other arcs on the basis of the data on the respective heating points; examines the degree of parallelism between each of the straight lines and a reference line that is a straight line showing the direction of a central axis of a cylinder provided that the target shape is approximately deemed as a part of the cylinder; if this degree of parallelism is within a predetermined range, performs grouping of the relevant heating points as the heating points of the same group; and connects the respective heating points of the same group by a straight line or a curve to determine a heating line.
- 4. A system for determining a heating line in the bending of a steel plate, comprising:a heating point determining unit which reads in target shape data on a target shape of a steel plate to be bent, and steel plate shape measurement data to be obtained by measuring the surface shape of the steel plate; divides a curve of the target shape of the steel plate into a plurality of successive segments; similarly divides a curve of the measured shape of the steel plate into a plurality of successive segments in correspondence with the curve of the target shape; determines the number of a plurality of congruent isosceles triangles, which are connected together while sharing their equal sides, for each segment on the basis of the radius of a division of the curve in each segment of the target shape of the steel plate, the radius of a division of the curve in each segment of the measured shape of the steel plate, and a separately set bending angle of the steel plate so that when the division of the curve in each segment of the target shape of the steel plate is regarded as an arc, the arc in each segment of the target shape of the steel plate can be approximated by a fold line defined by the bases of the plural congruent isosceles triangles and that when the division of the curve in each segment of the measured shape of the steel plate is regarded as an arc, the arc in each segment of the measured shape of the steel plate can be approximated by a fold line defined by the bases of a plurality of other congruent isosceles triangles which are connected together while sharing their equal sides, the number of the latter isosceles triangles being the same as the number of the former isosceles triangles whose bases constitute the approximating fold line for the target shape; divides the arc of the measured shape in each segment by the number of the isosceles triangles to form respective points on the arc; and calculates the coordinates of the respective points as heating points; and a heating line determining unit which reads in data on the heating points calculated by the heating point determining unit; draws straight lines from a certain heating point on a certain arc, as a starting point, to heating points on other arcs on the basis of the data on the respective heating points; examines the degree of parallelism between each of the straight lines and a reference line that is a straight line showing the direction of a central axis of a cylinder provided that the target shape is approximately deemed as a part of the cylinder; if this degree of parallelism is within a predetermined range, performs grouping of the relevant heating points as the heating points of the same group; and connects the respective heating points of the same group by a straight line or a curve to determine a heating line.
Priority Claims (4)
Number |
Date |
Country |
Kind |
9-263748 |
Sep 1997 |
JP |
|
9-263751 |
Sep 1997 |
JP |
|
10-261088 |
Sep 1998 |
JP |
|
10-261089 |
Sep 1998 |
JP |
|
Parent Case Info
This application is a divisional of application Ser. No. 09/834,604, filed on Apr. 16, 2001, now U.S. Pat. No. 6,385,556 which is a divisional of application Ser. No. 09/159,758, filed on Apr. 16, 2001, now U.S. Pat. No. 6,298,310 the entire contents of which are hereby incorporated by reference and for which priority is claimed under 35 U.S.C. §120; and this application claims priority of Application Nos. 9-263748; 9-263751; 10-261088; and 10-261089 filed in Japan on Sep. 29, 1997; Sep. 29, 1997; Sep. 16, 1998; and Sep. 16, 1998 under 35 U.S.C. §119.
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