Straightening machine and method for straightening a metal strip or a flat metal part

Abstract

A straightening machine ( 1 ) and a method for straightening a metal strip or a flat metal part ( 16 ) by the straightening machine, having upper straightening rollers ( 3 ) in an upper roller mill ( 2 ) and lower straightening rollers ( 6 ) in a lower roller mill ( 5 ). The upper and lower straightening rollers form upper and lower roller mill planes with a straightening gap therebetween and act on the metal strip to be straightened. In a working position, the upper roller mill plane forms an operating angle to the lower roller mill plane. The straightening gap ( 11 ) is changed by adjusting the upper roller mill plane relative to the lower roller mill plane. Before or at the start of a straightening process, the upper and/or lower roller mill is put in a starting position with a widened straightening nip, at least until a front end of the material strip has entered the inlet of the working region and for the rest of the straightening process, the upper and/or lower roller mill is put in the working position.

1 . A method for straightening a material strip or a flat material part composed of a material which is plasticizable using a straightening machine ( 1 ) with a number of upper straightening rollers ( 3 ) in an upper roller mill ( 2 ) and a number of lower straightening rollers ( 6 ) in a lower roller mill ( 5 ), which form a straightening gap ( 11 ) between an inlet ( 12 ) and an outlet ( 13 ) of the straightening machine ( 1 ) in an operating region between the upper and the lower roller mill ( 2 ,  5 ), the upper and the lower straightening rollers ( 3 ,  6 ) in an operating position of the upper and lower roller mill ( 2 ,  5 ) act at least temporarily from top to bottom on the material strip or material part to be straightened and guide the material strip or part in an operating direction ( 14 ) from the inlet ( 12 ) to the outlet ( 13 ) of the operating region through the straightening machine ( 1 ), at least a part of axes ( 9 ) of the upper straightening rollers ( 3 ) form an upper roller mill plane ( 4 ) and at least a part of axes ( 9 ) of the lower straightening rollers ( 6 ) forms lower roller mill plane ( 7 ), which in the operating position are parallel or at a predetermined operating angle ( 8 ) to one another, the method comprising:
 in order to change the straightening gap ( 11 ), at least one of adjusting the upper roller mill ( 2 ) relative to the lower roller mill ( 5 ) or adjusting the lower roller mill ( 5 ) relative to the upper roller mill ( 2 ); and   prior to or at a start of a straightening process, placing at least one of the upper or lower roller mill ( 2 ,  5 ) into a starting position at least until a front end of the material strip or material part has run into the inlet ( 12 ) of an operating region of the straightening machine ( 1 ) by widening the straightening gap ( 11 ) to a greater extent that at the outlet ( 13 ), widening the straightening gap ( 11 ) to a greater extent at the outlet ( 13 ) than at the inlet ( 12 ); and   for the further straightening process, advancing at least one of the upper or lower roller mill ( 2 ,  5 ) into an operating position.   
     
     
         2 . The method as claimed in  claim 1 , wherein the straightening gap ( 11 ) during placing into the starting position is widened to a greater extent at the inlet ( 12 ) than at the outlet ( 13 ) if the operating angle ( 8 ) opens toward the outlet ( 13 ) or the upper roller mill plane ( 4 ) is parallel to the lower roller mill plane ( 7 ), or the straightening gap ( 11 ) during placing into the starting position is widened to a greater extent at the outlet ( 13 ) than at the inlet ( 12 ) if the operating angle ( 8 ) opens toward the inlet ( 12 ). 
     
     
         3 . The method as claimed in  claim 1 , further comprising the method steps:
 (A) placing at least one of the upper or lower roller mill ( 2 ,  5 ) into the starting position; and   (B) advancing at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position,   wherein method step B is performed when or after the front end ( 17 ) of the material strip or material part ( 16 ) has reached a predetermined position ( 15 ) in the operating region.   
     
     
         4 . The method as claimed in  claim 3 , wherein a region of the inlet ( 11 ), or a location of one of the lower or upper straightening rollers ( 3 ,  6 ) is used as the predetermined position ( 15 ). 
     
     
         5 . The method as claimed in  claim 3 , wherein the front end ( 17 ) of the material strip or material part is detected by a sensor ( 18 ). 
     
     
         6 . The method as claimed in  claim 5 , wherein the sensor ( 18 ) is arranged at the predetermined position ( 15 ) and method step B is performed immediately after detection of the front end ( 17 ) of the material strip or material part ( 16 ) by the sensor ( 18 ). 
     
     
         7 . The method as claimed in  claim 5 , wherein the sensor ( 18 ) is arranged at a spacing ( 19 ) upstream of the predetermined position ( 15 ) in the operating direction ( 14 ), and the method further comprises determining a time delay until the predetermined position ( 15 ) of the front end ( 17 ) of the material strip or material part ( 16 ) is reached from a conveying speed of the material strip or material part and the spacing ( 19 ) between the sensor ( 18 ) and the predetermined position ( 15 ), and method step B is performed with or after the end of the time delay after detection of the front end ( 17 ) of the material strip or material part by the sensor ( 18 ). 
     
     
         8 . The method as claimed in  claim 1 , wherein at least one of a) the placing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the starting position is performed such that the straightening gap ( 11 ) in a region of the inlet ( 12 ) corresponds at least to a thickness of the material strip or material part ( 16 ) or b) the advancing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position is performed such that the straightening gap ( 11 ) in a region of the outlet ( 13 ) corresponds substantially to the thickness of the material strip or material part ( 16 ). 
     
     
         9 . The method as claimed in  claim 1 , wherein at least one of a) the placing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the starting position is performed such that the straightening gap ( 11 ) in a region of the outlet ( 13 ) corresponds at least to a thickness of the material strip or material part ( 16 ) or  12 ) the advancing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position is performed such that the straightening gap ( 11 ) in a region of the inlet ( 12 ) corresponds substantially to the thickness of the material strip or material part ( 16 ). 
     
     
         10 . The method as claimed in  claim 1 , wherein the advancing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position is performed continuously. 
     
     
         11 . The method as claimed in  claim 1 , wherein the advancing of at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position is performed in an incremental manner. 
     
     
         12 . The method as claimed in  claim 11 , wherein one step of the advancing is performed with or after passing at least one of one said lower or upper straightening roller ( 3 ,  6 ), and the advancing is performed in the step such that the spacing of the upper and lower straightening rollers ( 3 ,  6 ) at a downstream said upper and/or lower straightening roller ( 3 ,  6 ) corresponds substantially to the thickness of the material strip or material part ( 16 ). 
     
     
         13 . The method as claimed in  claim 1 , wherein at least one of the upper roller mill ( 2 ) or the lower roller mill ( 5 ) is moved at least partially via a pivoting movement into at least one of the starting position or the operating position. 
     
     
         14 . A straightening machine ( 1 ) for straightening a material strip or a flat material composed of a material which can be plasticized, the straightening machine comprising:
 a number of upper straightening rollers ( 3 ) in an upper roller mill ( 2 );   a number of lower straightening rollers ( 6 ) in a lower roller mill ( 5 );   a straightening gap formed between an inlet ( 12 ) and an outlet ( 13 ) of the straightening machine ( 1 ) in an operating region between the upper and the lower roller mills ( 2 ,  5 ), the straightening gap ( 11 ), in an operating position of the upper and lower roller mills ( 2 ,  5 ) being configured to act at least temporarily from top to bottom on the material strip or material part to be straightened and guide the material strip or material part in an operating direction ( 14 ) from the inlet ( 12 ) to the outlet ( 13 ) of the working region through the straightening machine ( 1 );   at least a part of axes ( 9 ) of the upper straightening rollers ( 3 ) form an upper roller mill plane ( 4 ) and at least a part of axes ( 9 ) of the lower straightening rollers ( 6 ) form a lower roller mill plane ( 7 ) which in the operating position are parallel or at a predetermined operating angle ( 8 ) to one another;   in order to change the straightening gap ( 11 ), the upper roller mill ( 2 ) and the lower roller mill ( 5 ) are adjustable relative to one another, and are placeable at least into a starting position with a widened straightening gap ( 11 ) and are advanceable into the starting position;   a controller ( 22 ) configured to adjust the upper and lower roller mills ( 2 ,  5 ) with respect to one another;   a sensor ( 18 ) for detection of a front end ( 17 ) of the material strip or material part ( 16 ) to be straightened, the sensor configured to output a sensor signal to the controller ( 22 );   the controller ( 22 ) being further configured to adjust at least one of the upper or lower roller mill ( 2 ,  5 ) from the starting position into the operating position immediately after or with a time delay to the sensor signal; and   the upper roller mill ( 2 ) and the lower roller mill ( 5 ) are adjustable relative to one another such that the straightening gap ( 11 ) during placing into the starting position is widened to a greater extent at the inlet ( 12 ) than at the outlet ( 13 ), or is widened to a greater extent at the outlet ( 13 ) than at the inlet ( 12 ).   
     
     
         15 . The straightening machine as claimed in  claim 14 , wherein the controller ( 22 ) is configured to widen the straightening gap ( 11 ) during placing into the starting position at the inlet ( 12 ) to a greater extent than at the outlet ( 13 ) if the operating angle ( 8 ) opens toward the outlet ( 13 ) or the upper roller mill plane ( 4 ) is parallel to the lower roller mill plane ( 7 ), or to widen the straightening gap ( 11 ) during placing into the starting position at the outlet ( 13 ) to a greater extent than at the inlet ( 12 ) if the operating angle ( 8 ) opens toward the inlet ( 12 ). 
     
     
         16 . The straightening machine as claimed in  claim 14 , wherein the upper roller mill plane ( 4 ) encloses a starting angle ( 10 ) to the lower roller mill plane ( 7 ) in the starting position, and said starting angle ( 10 ) is not equal to the operating angle ( 8 ). 
     
     
         17 . The straightening machine as claimed in  claim 14 , wherein the sensor ( 18 ) is arranged at a height of a predetermined position ( 15 ), or upstream in the operating direction ( 14 ) at a spacing ( 19 ) in front of the predetermined position ( 15 ), wherein the predetermined position ( 15 ) lies in a region of the inlet ( 12 ), or corresponds to a location of one of the lower or upper straightening rollers. 
     
     
         18 . The straightening machine as claimed in  claim 17 , wherein the controller ( 22 ) is configured such that the time delay for the adjustment of at least one of the upper or lower roller mill ( 2 ,  5 ) into the operating position is determined from a conveying speed of the material strip or material part and the spacing ( 19 ) between the sensor ( 18 ) and the predetermined position ( 15 ). 
     
     
         19 . The straightening machine as claimed in  claim 14 , wherein the sensor ( 18 ) is a physical sensor. 
     
     
         20 . The straightening machine as claimed in  claim 14 , wherein at least one of a) the upper roller mill ( 2 ) is pivotable with respect to the lower roller mill ( 5 ) or b) the lower roller mill ( 5 ) is pivotable with respect to the upper roller mill ( 2 ) about a pivot axis, and the pivot axis lies outside an operating region of the straightening machine ( 1 ). 
     
     
         21 . The straightening machine as claimed in  claim 14 , wherein the upper roller mill ( 2 ) is retained in guides ( 20 ) of the straightening machine ( 1 ) and is movable up and down on the guides ( 20 ) relative to the lower roller mill ( 3 ), and the guides ( 20 ) are formed such that the upper roller mill ( 2 ) is at least one of adjustable or pivotable asymmetrically on the guides ( 20 ).