Abstract:
An uncoiling device having an uncoiler for uncoiling a strip is described. The uncoiler is arranged downstream from a thickness measuring device which measures the thickness of the unwound strip. Said thickness measuring device is arranged downstream from a straightening device which straightens the unwound strip. Said straightening device is arranged downstream from a machining device which further machines the straightened strip. The thickness of the trip is transmitted to a control device which controls the straightening machine and/or the machining device in accordance with the measured thickness of the strip.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the US National Stage of International Application No. PCT/EP2007/055475 filed Jun. 4, 2007, and claims the benefit thereof. The International Application claims the benefits of German application No. 10 2006 028 102.0 DE filed Jun. 19, 2006. Both of the applications are incorporated by reference herein in their entirety. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates to an uncoiling device that contains the following elements: 
         [0003]    an uncoiler for uncoiling a strip; 
         [0004]    a leveling machine disposed downstream of the uncoiler and provided for leveling the uncoiled strip; 
         [0005]    a height measuring device disposed downstream of the leveling machine and provided for registering the height position of the leveled strip; 
         [0006]    a machining device disposed downstream of the height measuring device and provided for further machining the leveled strip; 
         [0007]    a control device to which the uncoiled strip&#39;s thickness measured by the thickness measuring device and the registered height position can be conveyed and by which control values for the leveling machine can be determined on the basis of a determining rule as a function of the measured thickness of the uncoiled strip and at least the leveling machine can be controlled. 
       BACKGROUND OF INVENTION 
       [0008]    A device of said type is known from DE 10 2004 041 732 A1. It is used, for instance, when a plurality of strips are to be welded together. 
       SUMMARY OF INVENTION 
       [0009]    For setting the correct height position of the leading end and trailing end of the strip the leveling machine must have been correctly controlled. 
         [0010]    An object of the present invention is to provide an uncoiling device that can be operated in a more optimized manner. 
         [0011]    Said object is achieved by means of an uncoiling device having the features of the claims. 
         [0012]    The determining rule can be adapted by the control device as a function of the registered height position. 
         [0013]    The thickness measuring device is embodied preferably as a distance-based thickness measuring device. Examples of thickness measuring devices of said type are measuring devices that operate on an eddy-current basis and measuring devices based on propagation time. The latter operate on the basis of ultrasound or light, in particular by means of lasers. Distance-based thickness measuring devices are preferred particularly because they are compact, economical and reliable. In particular, already existing uncoiling devices can even be retrofitted with thickness measuring devices of said type. 
         [0014]    It is possible for the thickness measuring device to scan one side of the uncoiled strip. In that case it must be ensured that the non-scanned side of the strip is at a defined level. For example, it is possible for the uncoiled strip to run over a reference roller at the point at which it is scanned by the thickness measuring device. 
         [0015]    Alternatively it is possible for the thickness measuring device to scan two sides of the uncoiled strip. Although such an embodiment of the thickness measuring device necessitates a greater overhead in terms of equipment, that is offset by its being possible to register the thickness of the strip independently of its height position. 
         [0016]    It is possible for the uncoiler to be additionally controllable by the control device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    Further advantages and specifics will emerge from the following description of exemplary embodiments in conjunction with the drawings, which are basic representations, and the dependent claims: 
           [0018]      FIG. 1  shows an uncoiling device, 
           [0019]      FIG. 2  is a flowchart, 
           [0020]      FIGS. 3-5  show possible embodiments of thickness measuring devices, and 
           [0021]      FIG. 6  shows a possible embodiment of a machining device. 
       
    
    
     DETAILED DESCRIPTION OF INVENTION 
       [0022]    According to  FIG. 1 , an uncoiling device includes an uncoiler  1 . A strip  2  can be uncoiled by means of the uncoiler  1 . The strip  2  is typically a thin metal strip, for example a steel strip. It generally has a strip thickness d of 0.1 to 8.0 mm. 
         [0023]    Disposed downstream of the uncoiler  1  is a thickness measuring device  3 . The thickness d of the strip  2  can be dynamically measured by means of the thickness measuring device  3 . The measured strip thickness d is conveyed to a control device  4  by the thickness measuring device  3 . 
         [0024]    Disposed downstream of the thickness measuring device  3  is a leveling machine  5 . The leveling machine  5  has a plurality of rollers  6 . The rollers  6  are arranged mutually displaced in a strip running direction x. They can be applied against the strip  2  in an alternating manner from above and/or from below. 
         [0025]    The strip  2  can be leveled by means of the rollers  6  of the leveling machine  5 , meaning that a horizontal height position h can be set at which a leading end  7  of the strip  2  and a trailing end of the strip  2  enter a machining device  8 . The machining device  8  is disposed downstream of the leveling machine  5 . The strip  2  is further machined by it. 
         [0026]    Disposed between the leveling machine  5  and the machining device  8  is a height measuring device  9 . The height position h of the strip  2  is registered by it and conveyed to the control device  4 . 
         [0027]    The control device  4  typically controls the entire uncoiling device, which is to say the uncoiler  1 , the leveling machine  5  and the machining device  8 . This case will be explained below in conjunction with  FIG. 2 . It would, however, basically suffice for the control device  4  to control the leveling machine  5 —in particular the leveling machine  5  and the machining device  8 . 
         [0028]    According to  FIG. 2 , the control device  4  initially controls the uncoiler  1  at a step S 1  in such a way that the uncoiler  1  starts uncoiling the strip  2 . 
         [0029]    At a step S 2  the control device  4  accepts the strip thickness d registered by the thickness measuring device  3 . 
         [0030]    At a step S 3  the control device  4  checks whether the strip thickness d conveyed to it is different from zero, meaning whether the strip  2  is being registered by the thickness measuring device  3 . If that is the case, the control device  4  will at a step S 4 —possibly with a suitable time lag—control the leveling machine  5  as a function of the registered thickness d. Within the scope of step S 4  the control device  4  can in particular determine on the basis of a determining rule control values A* for the individual rollers  6  of the leveling machine  5  as a function of the measured thickness d of the uncoiled strip  2  and convey the determined control values A* to the leveling machine  5 . 
         [0031]    At a step S 5  the control device  4  can—possibly with a suitably specified time lag—determine control values B* for the machining device  8  and convey them to the machining device  8 . The control values B* for the machining device  8  can likewise depend on the measured thickness d of the uncoiled strip  2 . For example, a point in time can be determined as of which the actual strip thickness d deviates from a setpoint thickness d* by no more (or less) than a permissible thickness tolerance δd. In this case the machining device  8  can be controlled in such a way, for example, that the leading end  7  of the strip will be separated from the rest of the strip  2  at the corresponding point on the strip  2 . A distance which cutters of a corresponding separating device have in the strip running direction x can additionally be set as a function of the measured thickness d of the uncoiled strip  2 . 
         [0032]    At a step S 6  the control device  4  checks whether the strip  2  has yet reached the height measuring device  9 . This can be determined by means of, for example, a simple tracking method generally familiar to persons skilled in the relevant art. 
         [0033]    At a step S 7  the control device  4  accepts the height position h, registered by the height measuring device  9 , of the leveled strip  2  and as a function of the registered height position h adapts the determining rule on the basis of which it determines the control values A* for the leveling machine  5 . In particular the control device  4  can compare the registered height position h with a setpoint height position h* and adapt the determining rule on the basis of the comparison. 
         [0034]    Adapting determining rules is as such generally familiar to persons skilled in the relevant art. For example, adaptive rules and model-based determining methods operate on these principles. 
         [0035]    At a step S 8  the control device  4  checks whether the strip  2  has reached the machining device  8 . This check, too, can be performed by means of, for example, a tracking method. Alternatively it is possible for a corresponding feedback message to be conveyed to the control device  4  by the machining device  8 . 
         [0036]    If the strip  2  has not yet reached the machining device  8 , the control device  4  returns to step S 2 . If the strip  2  has already reached the machining device  8 , the control device  4  resumes executing the method at a step S 9 . 
         [0037]    At step S 9  the control device  4  controls the leveling machine  5  in such a way that the latter stops leveling the strip  2 . In particular the rollers  6  are disengaged from the strip  2 . Controlling of the uncoiler  1  and machining device  8  will, by contrast, be retained within the scope of step S 9 . For example, a strip speed v at which the strip  2  is uncoiled can be increased within the scope of step S 9  depending on further machining. 
         [0038]    At a step S 10  the control device  4  again accepts the thickness d of the strip  2  from the thickness measuring device  3 . 
         [0039]    At a step S 11  the control device  4  checks whether the registered strip thickness d has the value zero. 
         [0040]    If the strip thickness d does not have the value zero, at a step S 12  the control device  4  will—possibly again with a suitably specified time lag—control the machining device  8  in accordance with the registered thickness d of the strip  2 . For example, it is possible to register—analogously to the procedure for the leading end  7  of the strip—as of what point in time the strip thickness d deviates from the setpoint thickness d* by more than the permissible thickness tolerance  6   d . In this case the machining device  8  can be controlled in such a way as to separate a trailing end of the strip, not identified further in the FIGs, from the rest of the strip  2 . The control device  4  thereupon returns to step S 9 . 
         [0041]    The trailing end of the strip will have passed by the thickness measuring device  3  if the registered thickness d of the strip  2  has reached the value zero. In this case the control device  4  will, at a step S 13 , adjust controlling of the uncoiler  1  and machining device  8  accordingly. For example, the strip speed v can be reduced. The leveling machine  5  can also be controlled again. 
         [0042]    The thickness measuring device  3  can be embodied basically in any manner. For example, it can operate with radiation that penetrates the strip  2 . Examples of radiation of said type are x-radiation and gamma radiation. Preferably, however, the thickness measuring device is embodied as a distance-based thickness measuring device  3 , particularly one based on propagation time. Thickness measuring devices  3  of said type operate, not with penetrating radiation, but, for example, with radiation that is reflected from the strip  2 . Examples of suitable types of radiation are sound (in particular ultrasound) and light, particularly laser light. The wavelength of light used can possibly be in the visible, infrared or even ultraviolet range. 
         [0043]      FIGS. 3 to 5  show examples of thickness measuring devices  3  based on propagation time. 
         [0044]    According to  FIG. 3 , the thickness measuring device  3  scans one side of the uncoiled strip  2  at a scanning point  10 . The term “scanning point” relates in this context not to the side of the strip  2  that is scanned but to the position in the strip running direction x at which the strip  2  is scanned. 
         [0045]    According to  FIG. 3 , the uncoiled strip  2  runs over a reference roller  11  at the scanning point  10 . According to  FIG. 4 , the scanning point  10  is located between two guide rollers  12 . 
         [0046]    According to  FIG. 5 , the thickness measuring device  3  scans two sides of the uncoiled strip  2 . In this case there can be no reference roller at the scanning point  10 . 
         [0047]    The height measuring device  9  can—provided it is present—be embodied similarly to the thickness measuring device  3 . Scanning on one side without a reference roller will generally suffice for the height measuring device  9 . 
         [0048]      FIG. 6  shows a typical embodiment of the machining device  8 . According to  FIG. 6 , the machining device  8  has a plurality of partial devices  13  to  15 . According to  FIG. 6 , the partial device  13  nearest the leveling machine  5  is embodied in the form of shears  13 . In particular the leading end  7  of the strip and the trailing end of the strip can be separated from the rest of the strip  2  by means of the shears  13 . The shears  13  can preferably move in the strip running direction x (being what are termed flying shears). This is indicated in  FIG. 6  by a double arrow next to the shears  13 . 
         [0049]    According to  FIG. 6 , the partial device  14  disposed downstream of the shears  13  is embodied as a welding device  14 . The leveled strip  2  can be welded to another strip  2 ′ by means of the welding device  14 . 
         [0050]    According to  FIG. 6 , the partial device  15  disposed downstream of the welding device  14  is embodied as a strip store  15 . It could alternatively be embodied as a cleaning device. The other strip  2 ′ can be intermediately stored by means of the strip store  15 . The strip store  15  is typically embodied as what is termed a looping pit. 
         [0051]    Optimized operation of the leveling machine  5  is possible by the uncoiling device. The thickness measuring device  3  is economical, compact and reliable. The strip  2  can be transported more quickly than in the case of the prior art. The strip store  15  can furthermore be dimensioned smaller than in the case of the prior art. 
         [0052]    The above description serves exclusively to explain the present invention. By contrast, the scope of protection of the present invention is to be determined exclusively by the attached claims.