Stretching-bending-straightening system and method of the actuation thereof

Abstract

In a stretching-bending-straightening system and a method for the actuation thereof, material in strip form is fed to a high-tension region (50) and a low-tension region (52), wherein the low-tension region (52) is arranged downstream of the high-tension region (50). A bending-straightening unit is arranged in the high-tension region (50). A measuring system determines first measured values in the high-tension region (50). A controller (C) is intended and suitable for determining a deviation of the first measured values from a setpoint value of the bending-straightening result and for determining at least one manipulated variable for the bending-straightening unit in dependence on the determined deviation within a first closed control loop. By additionally providing at least one measuring system for determining second measured values in the low-tension region, by having a controller (C) intended and suitable for determining a deviation of the second measured values from the setpoint value of the bending-straightening result and for determining the at least one manipulated variable in dependence on the determined deviation within a second closed control loop, and by providing selecting means that are intended and suitable for selecting the first or second closed control loop for reducing the deviation of the first and/or second measured values from the predetermined or predeterminable setpoint value, a stretching-bending-straightening system and a method for the actuation thereof are designed in such a way that the quality of the strips processed thereby is increased.

1 .- 16 . (canceled) 
     
     
         17 . A stretching-bending-straightening system, having
 a feed means for feeding a material in strip form in a movement direction into a high-tension region and a low-tension region, wherein the low-tension region is arranged downstream of the high-tension region in the movement direction,   a bending-straightening apparatus, which is situated in the high-tension region,   at least one measuring system for determining first measured values in the high-tension region,   a controller, which is intended and suitable for determining a deviation of the first measured values from a predefined or predefinable desired value of the bending-straightening result and for determining at least one manipulated variable for the bending-straightening apparatus depending on the determined deviation within a first closed control loop,   an adjustment means for influencing the manipulated variable,   wherein there is provided in addition at least one measuring system for determining second measured values in the low-tension region,   
       wherein a controller is intended and suitable for determining a deviation of the second measured values from the predefined or predefinable desired value of the bending-straightening result and for determining the at least one manipulated variable depending on the determined deviation within a second closed control loop, and 
       wherein selection means are provided and are intended and suitable for selecting the first closed control loop or the second closed control loop in order to reduce the deviation of at least one of the first or second measured values from the predefined or predefinable desired value. 
     
     
         18 . A stretching-bending-straightening system in accordance with  claim 17 , wherein the controller is one single controller, which is intended and suitable for determining simultaneously the deviation of the first and the second measured values from the predefined or predefinable desired value, and in that the selection means are intended and suitable for selecting the first or the second closed control loop alternatively. 
     
     
         19 . A stretching-bending-straightening system in accordance with  claim 17 , wherein at least one analysis unit for analysing at least one of the first or the second measured values is provided, and wherein the selection means are intended and suitable for selecting the first or the second closed control loop depending on the analysis. 
     
     
         20 . A stretching-bending-straightening system in accordance with  claim 17 , wherein display means for displaying the first and second measured values are provided. 
     
     
         21 . A stretching-bending-straightening system in accordance with  claim 17 , wherein the selection means are provided for manual selection by an operator. 
     
     
         22 . A stretching-bending-straightening system in accordance with  claim 17 , wherein the at least one measuring system for determining the first measured values in the high-tension region is formed by a measuring roller arranged after the bending-straightening apparatus. 
     
     
         23 . A stretching-bending-straightening system in accordance with  claim 22 , wherein a roller of a tension S-block is replaced by the measuring roller having sensors deployed on its circumference, the running surface of the measuring roller being covered by a resilient coating. 
     
     
         24 . A stretching-bending-straightening system in accordance with  claim 17 , wherein the at least one measuring system for determining the second measured values is formed by a measuring roller arranged after the bending-straightening apparatus and after the tension S-block in the low-tension region). 
     
     
         25 . A stretching-bending-straightening system in accordance with  claim 24 , wherein the measuring roller has adjacently arranged measuring segments having at least one sensor. 
     
     
         26 . A stretching-bending-straightening system in accordance with  claim 25 , wherein the at least one sensor comprises two force sensors. 
     
     
         27 . A stretching-bending-straightening system in accordance with  claim 17 , wherein storage means for storing the operating parameters adjusted as a result of the first or second closed control loop are provided, and wherein a data bank is provided, which is intended and suitable for storing these operating parameters together with data regarding the material processed by these operating parameters. 
     
     
         28 . A method for operating a stretching-bending-straightening system, said method comprising the steps:
 feeding a material in strip form in a movement direction into a high-tension region and a low-tension region, wherein a bending-straightening apparatus is arranged in the high-tension region, and wherein the low-tension region is arranged downstream of the high-tension region in the movement direction,   determining first measured values in the high-tension region,   determining a deviation of the first measured values from a predefined or predefinable desired value of the bending-straightening result,   determining at least one manipulated variable for the bending-straightening apparatus depending on the determined deviation within a closed control loop,   determining second measured values in the low-tension region,   determining a deviation of the second measured values from the predefined or predefinable desired value of the bending-straightening result,   determining the at least one manipulated variable depending on the determined deviation within a second closed control loop,   selecting the first or the second closed control loop in order to reduce the deviation of at least one of the first or second measured values from the predefined or predefinable desired value.   
     
     
         29 . A method in accordance with  claim 28 , wherein the deviation of the first and the second measured values from the predefined or predefinable desired value is determined simultaneously by means of one single controller, and wherein the first closed control loop or the second closed control loop is selected alternatively. 
     
     
         30 . A method in accordance with  claim 28 , wherein the first and the second measured values are analyzed on the basis of predetermined criteria in view of achieving a bending-straightening result, and wherein the first or the second closed control loop is selected depending on the analysis. 
     
     
         31 . A method in accordance with  claim 28 , wherein the first and second measured values are displayed to an operator simultaneously. 
     
     
         32 . A method in accordance with  claim 28 , wherein the first closed control loop or the second closed control loop is selectable manually by an operator. 
     
     
         33 . A method in accordance with  claim 28 , wherein the method is operated initially on the basis of the first measured values from the high-tension region in the first closed control loop, until the straightened material in strip form reaches the measuring roller in the low-tension region, and wherein a switch is then made to the second closed control loop in the low-tension region. 
     
     
         34 . A method in accordance with  claim 28 , including storing, in a data bank, operating parameters already determined in advance during operation of the stretching bending-straightening system, jointly with data regarding the material processed with said operating parameters, and using the stored data for the processing of comparable materials.