Abstract:
The present invention relates to a method and an apparatus for continuously manufacturing metal sheets. The method includes: (a) providing a first metal coil having a first end and a second end; (b) continuously driving the first end of the first metal coil to move forward; (c) providing a second metal coil having a first end and a second end; and (d) lapping and rolling the first end of the second metal coil and the second end of the first metal coil, so that the second metal coil moves forward following the first metal coil. In this way, the present invention only causes a few seconds&#39; delay in rolling, so a small piler is needed, thus reducing the space of the production line and saving the facility cost.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a method and an apparatus for continuously manufacturing metal sheets, and more particularly to a method and an apparatus for continuously manufacturing metal sheets by rolling. 
         [0003]    2. Description of the Related Art 
         [0004]      FIG. 1  shows a schematic view of a conventional apparatus for continuously manufacturing metal sheets. The conventional continuously manufacturing apparatus  1  includes an unwinder  11 , a welding device  12 , a piler  13 , a main processing device  14 , and a winder  15 . The unwinder  11  is used for unwinding a metal coil  16  (for example, a steel coil). The main processing device  14  is used for processing the metal coil  16  passing through it, and the processing method is cold rolling, acid pickling, annealing, zinc-plating, balking varnish, finishing, tempering, leveling, punching, or roll forming. The winder  15  is used for continuously winding the metal coil  16  passing through the main processing device  14 . 
         [0005]    When the unwinder  11  finishes unwinding the metal coil  16 , as the main processing device  14  and the winder  15  must keep running, another metal coil  16  should be fitted onto the unwinder  11  and its front end must be joined to the rear end of the previous metal coil  16 , in order not to interrupt the production line. In the conventional continuously manufacturing apparatus  1 , the two metal coils  16  are joined as follows: the ends of the two metal coils  16  are first abutted, and then welded together by the welding device  12 . 
         [0006]    It takes about 20-30 seconds for the welding device  12  to weld the ends of the two metal coils  16 . During welding, the main processing device  14  and the winder  15  still keep running, so the piler  13  is needed for piling articles. The piler  13  includes a plurality of rollers  131 . The rollers  131  are capable of moving upward and downward, so as to adjust the total length of the metal coil  16  in the piler  13 , thus achieving the purpose of article piling. 
         [0007]    The conventional continuously manufacturing apparatus  1  has the following defects. First the alignment of the two ends of the two metal coils  16  needs to be highly accurate. That is, the ends of the two metal coils  16  must be perfectly aligned with each other in order not to affect the subsequent process, and this results in an increase of the manufacturing cost. Secondly, after welding, a protruding welding seam  161  is left at the ends of the two metal coils  16 , as shown in  FIG. 2 , and thus a device for leveling the welding seam  161  must be added. Thirdly, the piler  13  is not only expensive, but also occupies a large space. 
         [0008]    Therefore, an innovative and advanced method and apparatus for continuously manufacturing metal sheets are needed to solve the above problems. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is mainly directed to a method for continuously manufacturing metal sheets, which includes the following steps: (a) providing a first metal coil having a first end and a second end; (b) continuously driving the first end of the first metal coil to move forward; (c) providing a second metal coil having a first end and a second end; and (d) lapping and rolling the first end of the second metal coil and the second end of the first metal coil, so that the second metal coil moves forward following the first metal coil. 
         [0010]    The present invention is further directed to an apparatus for continuously manufacturing metal sheets which includes a first unwinder, a second unwinder, a rolling device, and a conveyor device. The first unwinder is used for unwinding a first metal coil. The second unwinder is used for unwinding a second metal coil. The rolling device is used for rolling one end of the first metal coil and one end of the second metal coil. The conveyor device is used for continuously driving the first metal coil and the second metal coil joined to the first metal coil. 
         [0011]    The first end of the second metal coil overlaps the second end of the first metal coil, so the alignment does not need to be highly accurate as in the conventional continuously manufacturing apparatus. Moreover, as the upper and lower surfaces of the rolled portion are even, the device for leveling the welding seam as in the conventional continuously manufacturing apparatus is unnecessary. Further, the present invention only makes a delay of less than 3 seconds in rolling, so a small piler is needed, thus reducing the space of the production line and saving the facility cost. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a schematic view of a conventional apparatus for continuously manufacturing metal sheets; 
           [0013]      FIG. 2  is a schematic view of a welding seam left after welding according to a conventional joining manner; 
           [0014]      FIG. 3  is a schematic view of an apparatus for continuously manufacturing metal sheets according to the present invention; 
           [0015]      FIG. 4  is a schematic view of a rolling device in the apparatus for continuously manufacturing metal sheets according to the present invention; 
           [0016]      FIG. 5  shows a rolled portion after rolling according to a joining manner of the present invention; and 
           [0017]      FIG. 6  is a flow chart of a method for continuously manufacturing metal sheets according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]      FIG. 3  shows a schematic view of an apparatus for continuously manufacturing metal sheets according to the present invention. The continuously manufacturing apparatus  3  includes a first unwinder  31 , a second unwinder  32 , a preprocessing device  33 , a rolling device  34 , a post-processing device  35 , a main processing device  36 , a conveyor device (for example, a plurality of pulleys  41 ), and a winder  37 . The first unwinder  31  is used for unwinding a first metal coil  38 . The first metal coil  38  has a first end (front end) and a second end  381  (rear end). The unwound first metal coil  38  is a flat sheet, and is driven by the conveyor device to enter the main processing device  36 . The main processing device  36  is used for processing the first metal coil  38  passing through it, and the processing method is cold rolling, acid pickling, annealing, zinc-plating, baking varnish, finishing, tempering, leveling, punching, or roll forming. 
         [0019]    Afterward, the first metal coil  38  passing through the main processing device  36  is wound by the winder  37  or directly reprocessed (for example, by punching shear). In this embodiment, the first end of the first metal coil  38  is wound by the winder  37 . 
         [0020]    The second unwinder  32  is used for unwinding a second metal coil  39 . The second metal coil  39  has a first end (front end)  391  and a second end (rear end). The unwound second metal coil  39  is a flat sheet, and is driven by the conveyor device. The second metal coil  39  and the first metal coil  38  may be of the same material or of different materials. When the first unwinder  31  finishes unwinding the first metal coil  38 , as the main processing device  36  and the winder  37  must keep running, the second metal coil  39  should be fitted onto the second unwinder  32  to be unwound and the first end  391  of the second metal coil  39  must be joined to the second end  381  of the first metal coil  38 , in order not to interrupt the production line. 
         [0021]    The preprocessing device  33  is used for preprocessing the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38 . In this embodiment, the preprocessing device  33  includes a surface treatment device (not shown), for treating surfaces to be joined. The surfaces to be joined include a lower surface of the first end  391  of the second metal coil  39  and an upper surface of the second end  381  of the first metal coil  38 . The method of surface treatment is selected from among mechanical polishing, mechanical sand-blasting, stamping, and plasma spraying, or combinations thereof. Surface treatment is employed to remove an oxide layer or oil film on the surfaces to be joined, so as to expose the metal substances on the lower surface of the first end  391  of the second metal coil  39  and the upper surface of the second end  381  of the first metal coil  38 , thereby achieving an effect of joining by rolling. For example, if the materials of the second metal coil  39  and the first metal coil  38  are both steel, mechanical polishing and mechanical sand-blasting are adopted in sequence. If the material of the second metal coil  39  or the first metal coil  38  is aluminum, only mechanical polishing is adopted, and mechanical sand-blasting is unnecessary. 
         [0022]    In other applications, the preprocessing device  33  further includes a heating device (not shown), for heating the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38 . 
         [0023]      FIG. 4  shows a schematic view of a rolling device in the apparatus for continuously manufacturing metal sheets according to the present invention. The rolling device  34  is used for rolling the second end  381  of the first metal coil  38  and the first end  391  of the second metal coil  39 . In this embodiment, the rolling device  34  includes two rollers  341 . When the first end  391  of the second metal coil  39  overlaps the second end  381  of the first metal coil  38 , the rollers  341  contact and roll the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38 , so as to form a rolled portion  40  ( FIG. 5 ). 
         [0024]    Again referring to  FIG. 3 , the post-processing device  35  is used for post-processing the rolled portion  40  between the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38 . In this embodiment the post-processing device  35  includes at trimming device (not shown), for trimming off protruding portions at both sides of the rolled portion  40 . In other applications, the post-processing device  35  includes a marking device (not shown), for forming a mark on the rolled portion  40 . 
         [0025]    Afterward, the conveyor device continuously drives the first metal coil  38  and the second metal coil  39  joined to the first metal coil  38  to enter the main processing device  36 . Then, the main processing device  36  processes the second metal coil  39  passing through it. Again, the processing method is cold rolling, acid pickling, annealing, zinc-plating, baking varnish, finishing, tempering, leveling, punching, or roll forming. 
         [0026]    Afterward, the second metal coil  39  passing through the main processing device  36  is wound by the winder  37  or directly reprocessed (for example, by punching shear). In this embodiment, the second metal coil  39  is continuously wound by the winder  37  after the first metal coil  38 . 
         [0027]    It is understood that when the second unwinder  32  finishes unwinding the second metal coil  39 , if necessary, another metal coil is fitted onto the first unwinder  31  to be unwound and the front end of the metal coil must be joined to the second end of the second metal coil  39 , in order not to interrupt the production line. 
         [0028]    The present invention has the following advantages. Firstly, the first end  391  of the second metal coil  39  overlaps the second end  381  of the first metal coil  38 , so the alignment does not need to be highly accurate as in the conventional continuously manufacturing apparatus  1 . Secondly, as the upper and lower surfaces of the rolled portion  40  are even, the device for leveling the welding seam  161  as in the conventional continuously manufacturing apparatus  1  is unnecessary. Thirdly, the present invention only causes a delay of less than 3 seconds in rolling, so a small piler is needed, thus reducing the space of the production line and saving the facility cost. 
         [0029]      FIG. 6  shows a flow chart of a method for continuously manufacturing metal sheets according to the present invention. Referring to  FIG. 3 , the method for continuously manufacturing metal sheets according to the present invention includes the following steps. In Step S 601 , a first metal coil  38  having a first end and a second end  381  is provided. In Step S 602 , the first metal coil  38  is mainly processed by cold rolling, acid pickling, annealing, zinc-plating, baking varnish, finishing, tempering, leveling, punching, or roll forming. In Step S 603 , the first end of the first metal coil  38  is continuously driven to move forward, so that the first end of the first metal coil  38  is continuously wound or the first metal coil  38  is directly reprocessed (for example, by punching shear). In this embodiment, the first end of the first metal coil  38  is continuously wound by the winder  37 . 
         [0030]    In Step S 604 , a second metal coil  39  having a first end  391  and a second end is provided. 
         [0031]    In Step S 605 , the surfaces to be joined at the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38  are preprocessed. The surfaces to be joined include the lower surface of the first end  391  of the second metal coil  39  and the upper surface of the second end  381  of the first metal coil  38 . In this embodiment, the method of surface treatment is selected from among mechanical polishing, mechanical sand-blasting, stamping, and plasma spraying, or combinations thereof. Surface treatment is employed to remove an oxide layer or oil film on the surfaces to be joined, so as to expose the metal substances on the lower surface of the first end  391  of the second metal coil  39  and the upper surface of the second end  381  of the first metal coil  38 , thereby enhancing the joining effect. For example, if the materials of the second metal coil  39  and the first metal coil  38  are both steel, mechanical polishing and mechanical sand-blasting are adopted in sequence. If the material of the second metal coil  39  or the first metal coil  38  is aluminum, only mechanical polishing is adopted, and mechanical sand-blasting is unnecessary. In other applications, the preprocessing step is heating, so as to heat up the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38 . 
         [0032]    In Step S 606 , the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38  overlap each other and are rolled to form a rolled portion  40 , so that the second metal coil  39  moves forward following the first metal coil  38 . 
         [0033]    In Step S 607 , the rolled portion  40  between the first end  391  of the second metal coil  39  and the second end  381  of the first metal coil  38  is post-processed. In this embodiment, the post-processing step is trimming off protruding portions at both sides of the rolled portion  40 . In other applications, the post-processing step is forming a mark on the rolled portion  40 . 
         [0034]    In Step S 608 , the second metal coil  39  is mainly processed. After the first metal coil  38  is mainly processed, the second metal coil  39  joined to the first metal coil  38  is then mainly processed. Again, the processing method is cold rolling, acid pickling, annealing, zinc-plating, baking varnish, finishing, tempering, leveling, punching, or roll forming. 
         [0035]    Afterward, the second metal coil  39  is wound or directly reprocessed (for example, by punching shear) In this embodiment, the second metal coil  39  is continuously wound after the first metal coil  38 . It is understood that, when the second metal coil  39  is completely unwound, if necessary, another metal coil is unwound and the front end of the metal coil must be joined to the second end of the second metal coil  39 , in order not to interrupt the production line. 
         [0036]    While several embodiments of the present invention have been illustrated and described, various modifications and improvements can be made by those skilled in the art. The embodiments of the present invention are therefore described in an illustrative but not restrictive sense. It is intended that the present invention should not be limited to the particular forms as illustrated, and that all modifications which maintain the spirit and scope of the present invention are within the scope defined in the appended claims.