Abstract:
A roll straightener serving as both zigzag type and opposed type and capable of being easily switched from one to the other between the zigzag type and the opposed type and being manufactured at low cost is disclosed. The roll straightener has odd-numbered pairs of upper and lower rolls. Plural lower rolls ( 22, 23, 24 ) from a second lower roll ( 22 ) counted from an insertion side of a work ( 10 ) up to a lower roll ( 24 ) located at a middle position are made movable in both vertical and transverse directions of the rolls, while the other upper rolls ( 11, 12, 13, 14, 15, 16, 17 ) and lower rolls ( 21, 25, 26, 27 ) are made movable in only the vertical direction. As a result, a change can be made easily from one to the other between a zigzag type roll straightener and an opposed type roll straightener and the manufacturing cost is so much reduced.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a roll straightener for straightening a work.  
         [0003]     2. Description of the Related Art  
         [0004]     Heretofore, there has been known a roll straightener wherein plural pairs of rolls are arranged in plural rows up and down and a work is passed between upper and lower rolls so as to be straightened. There are a case where the work is passed without rotation and a case where it is passed under rotation. Straighteners are broadly classified into a zigzag type and an opposed type, depending on the layout of rolls.  
         [0005]     First, a zigzag type roll straightener will be described with reference to  FIG. 5 . For example, the zigzag type roll straightener is provided with seven upper rolls  51 ,  52 ,  53 ,  54 ,  55 ,  56 ,  57  and seven lower rolls  61 ,  62 ,  63 ,  64 ,  65 ,  66 ,  67 . A pair of upper roll  51  and lower roll  61  are aligned vertically with each other on an inlet side where a work  10  such as a pipe is introduced, while on an outlet side there are disposed three pairs of upper rolls  55 ,  56 ,  57  and lower rolls  65 ,  66 ,  67  so that each pair of rolls are aligned vertically with each other. The three upper rolls  55 ,  56  and  57  are set at the same height and likewise the three lower rolls  65 ,  66  and  67  are set at the same height. Second to fourth upper rolls  52 ,  53 ,  54  and lower rolls  62 ,  63 ,  64 , which are close to the inlet side (the rolls located closest to the inlet side are assumed to be first rolls), are disposed in a zigzag fashion (the upper and lower rolls assume horizontally alternate positions). The second to fourth upper rolls  52 ,  53  and  54  are positioned lower by a certain millimeter below the decimal than the other upper rolls  51 ,  55 ,  56  and  57 . Likewise, the second to fourth lower rolls  62 ,  63  and  64  are positioned higher by a certain millimeter below the decimal than the other lower rolls  61 ,  65 ,  66  and  67 .  
         [0006]     The work  10  is moved from between the inlet-side (first) upper roll  51  and lower roll  61  toward between the outlet-side (seventh) upper roll  57  and lower roll  67 . After passing the zigzag upper rolls  52 ,  53 ,  54  and lower rolls  62 ,  63 ,  64 , the work passes three pair of respectively vertically aligned upper rolls  55 ,  56 ,  57  and lower rolls  65 ,  66 ,  67 , whereby the work  10  is straightened. This zigzag type roll straightener is advantageous in that the roundness is good, but is markedly disadvantageous in that the strain is conspicuous.  
         [0007]     Next, an opposed type roll straightener is shown in  FIG. 6 . The opposed type roll straightener is disclosed in Japanese Patent Laid-Open Publication No. H08(1996)-24752 and is provided with, for example, seven upper rolls  71 ,  72 ,  73 ,  74 ,  75 ,  76 ,  77  and seven lower rolls  81 ,  82 ,  83 ,  84 ,  85 ,  86 ,  87 , which pairs are each aligned vertically. The seven pairs of upper and lower rolls are disposed in a chevron shape symmetric right and left with a central pair of upper and lower rolls as a vertex. This opposed type roll straightener is advantageous in that the strain is less conspicuous, but is disadvantageous in that the roundness is poor.  
         [0008]     Thus, the zigzag type and the opposed type each have a merit and a demerit contrary to each other with respect to roundness and strain. Therefore, it has so far been necessary for the trader concerned to provided two types of machines, i.e., zigzag type and opposed type straighteners, according to the work to be straightened. Consequently, it has been necessary to ensure a correspondingly increased space within the factory concerned; besides, the cost increases.  
         [0009]     On the other hand, if all the pairs of upper and lower rolls are made movable vertically and transversely, it may be possible for one roll straightener to serve as both zigzag type and opposed type. In such a roll straightener it is not necessary to provide two machines of zigzag type and opposed type, so that the space for a single machine suffices in the factory concerned.  
         [0010]     In the roll straightener wherein all the pairs of upper and lower rolls (a total of fourteen rolls) are made movable vertically and transversely, the cost can be reduced in comparison with the case where two types of roll straighteners are provided, but the cost is not so much reduced because a lot of means are required for such vertical and transverse movements. Moreover, for switching the zigzag type and the opposed type from one to the other, it is necessary to change the positions of the total of fourteen rolls in the vertical and transverse directions. Thus, a considerable time is required and the production efficiency is poor.  
       SUMMARY OF THE INVENTION  
       [0011]     It is an object of the present invention to provide a roll straightener serving as both zigzag type and opposed type, easy to switch from one to the other type and capable of being manufactured at low cost.  
         [0012]     In one aspect of the present invention there is provided a roll straightener having odd-numbered pairs of upper rolls and lower rolls, wherein a work is passed between the upper rolls and the lower rolls so as to be straightened, characterized in that on one of the upper rolls side and the lower rolls side a plurality of rolls from the second roll counted from a work insertion side up to an odd-numbered roll located at a middle position are made movable in both vertical and transverse directions of the rolls and the upper rolls and lower rolls, exclusive of the plural rolls movable in both vertical and transverse directions and inlet-side upper roll and lower roll and outlet-side upper roll and lower roll, are made movable in only the vertical direction. In another aspect of the present invention, the inlet-side upper roll and lower roll and the outlet-side upper roll and lower roll are made movable in only the vertical direction. In a further aspect of the present invention, the plural rolls movable in both vertical and transverse directions have respective rotating shafts, and there is provided a support member formed with elongated holes which support the plural rotating shafts vertically movably in an inserted state of the shafts into the holes.  
         [0013]     Of all the upper and lower rolls, the rolls movable in both vertical and transverse directions are only plural rolls located on either the upper rolls side or the lower rolls side and comprising rolls from the second roll counted from the work insertion side up to an odd-numbered roll located at a middle position, and the other rolls exclusive of inlet- and outlet-side rolls are made movable in only the vertical direction, whereby a change can be made in a short time from one to the other between the zigzag type and the opposed type and thus the roll straightener can be manufactured at low cost. Further, the shafts of the plural rolls movable in both vertical and transverse directions are supported by support means and the support means are moved, whereby the plural rolls can be easily moved laterally without the need of adjusting them each individually. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a schematic construction diagram of a roll straightener according to the present invention;  
         [0015]      FIG. 2  is a schematic construction diagram showing a state in which the roll straightener according to the present invention has been switched to an opposed type roll straightener;  
         [0016]      FIG. 3  is an enlarged diagram of a principal portion, showing a state in which some rolls in the roll straightener according to the present invention have been moved from the state of  FIG. 2 ;  
         [0017]      FIG. 4  is a schematic construction diagram showing a state in which the roll straightener according to the present invention has been switched to a zigzag type roll straightener;  
         [0018]      FIG. 5  is a schematic construction diagram of a conventional, known zigzag type roll straightener; and  
         [0019]      FIG. 6  is a schematic construction diagram of a conventional, known opposed type roll straightener. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0020]     The present invention will be described hereunder with reference to the accompanying drawings.  
         [0021]      FIG. 1  is a schematic construction diagram of a roll straightener according to the present invention. In the present invention there are used five or more odd-numbered pairs of upper and lower rolls. In this embodiment there are used seven pairs of upper and lower rolls. More specifically, there are used seven upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17  and seven lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26 ,  27 . The upper roll  11  and the lower roll  21  are disposed on an inlet side (first position) of a work  10 , while the upper roll  17  and the lower roll  27  are disposed on an outlet side (seventh position) of the work  10 . In the present invention there are provided rotating means for rotating the seven upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16  and  17 , moving means for moving the rotating means, rotating means for rotating the seven lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26  and  27 , and moving means for moving the rotating means. Since these rotating means and moving means are of known structures, their illustrations are omitted.  
         [0022]     The seven upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16  and  17  are movable in only the vertical direction and not movable in the transverse direction. The inlet-side upper roll  11  and the outlet-side upper roll  17  may be set so as not to move in the vertical direction (that is, not movable in the vertical and transverse directions). The five upper rolls  12 ,  13 ,  14 ,  15  and  16  are arranged at equal intervals of X. The spacing between the inlet-side upper roll  11  and the upper roll  12  adjacent thereto is set at Y and the spacing between the outlet-side upper roll  17  and the upper roll  16  adjacent thereto is also set at Y The spacing Y is set at a distance longer than the spacing X.  
         [0023]     Of the seven lower rolls, the lower rolls  21 ,  25 ,  26  and  27  are vertically aligned with the upper rolls  11 ,  15 ,  16  and  17  respectively. The lower rolls  21 ,  25 ,  26  and  27  are made movable in only the vertical direction and not movable in the transverse direction. The inlet-side lower roll  21  and the outlet-side lower roll  27  may be set so as not to move in the vertical direction (that is, not movable in the vertical and transverse directions).  
         [0024]     Of the seven lower rolls, the remaining three lower rolls  22 ,  23  and  24  are set so as to be movable in both vertical and transverse directions. That is, of the seven lower rolls, the three lower rolls  22 ,  23  and  24  from the second lower roll  22  up to the lower roll  24  located at the middle position are set so as to be movable in both vertical and transverse directions. According to the embodiment illustrated in  FIG. 1 , the three lower rolls  22 ,  23  and  24  out of the seven lower rolls are made movable in both vertical and transverse directions. However, in case of five lower rolls, two lower rolls from the second to the middle lower roll are made movable in both vertical and transverse directions, and in case of nine lower rolls, four lower rolls from the second to the middle lower roll are made movable in both vertical and transverse directions.  
         [0025]     Next, a description will be given about the case where the roll straightener according to the present invention is switched to an opposed type roll straightener. Of the seven pairs of upper and lower rolls, the upper rolls  11 ,  15 ,  16 ,  17  and the lower rolls  21 ,  25 ,  26 ,  27  are vertically aligned respectively and are all set so as not to move in the transverse direction. Of the remaining three pairs, the upper rolls  12 ,  13  and  14  are set so as not to move in the transverse direction, but since the lower rolls  22 ,  23  and  24  are movable in the transverse direction, the lower rolls  22 ,  23  and  24  are moved in the transverse direction into vertical alignment with the upper rolls  12 ,  13  and  14  respectively. As a result, all of the seven pairs of upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17  and lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26 ,  27  are vertically aligned respectively.  
         [0026]     Thereafter, the inlet-side upper roll  11  and the outlet-side upper roll  17  are set at the same height and the heights of the five upper rolls  12 ,  13 ,  14 ,  15  and  16  located between the upper rolls  11  and  17  are set in a chevron shape symmetric right and left with a middle portion being higher than the other portion ( FIG. 2 ). The height of the middle upper roll  14  located at the highest position is usually set about several millimeters higher than the upper rolls  11  and  17  located at both ends. Likewise, the inlet-side lower roll  21  and the outlet-side lower roll  27  are set at the same height and the heights of the five lower rolls  22 ,  23 ,  24 ,  25  and  26  located between the lower rolls  21  and  27  are set in a chevron shape symmetric right and left with a middle portion being higher than the other portion ( FIG. 2 ). The height of the middle lower roll  24  located at the highest position is usually set about several millimeters higher than the lower rolls  21  and  27  located at both ends. The spacing between each pair of upper and lower rolls vertically aligned with each other is set so as to permit insertion therethrough of the work  10 . By thus moving the upper and lower rolls it is possible to constitute an opposed type roll straightener. The work  10  can be straightened by passing it between the upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17  and the lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26 ,  27 .  
         [0027]     Next, a description will be given about switching the roll straightener according to the present invention from the opposed type to a zigzag type. In an initial state, all of the seven pairs of upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17  and lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26 ,  27  are vertically aligned respectively; besides, all the upper rolls are at the same height and so are all the lower rolls ( FIG. 1 ). From the state of  FIG. 1 , the three transversely movable lower rolls  22 ,  23  and  24  are moved toward the inlet-side lower roll  21  (leftward in the FIG.) ( FIG. 3 ) while being held at equal spacing X.  
         [0028]     In the state of  FIG. 3  in which the three lower rolls  22 ,  23  and  24  have been moved toward the inlet-side lower roll  21 , the lower roll  22 , in the horizontal direction, is positioned between the upper rolls  11  and  12 , the lower roll  23  is positioned between the upper rolls  12  and  13 , and the lower roll  24  is positioned between the upper rolls  13  and  14 . Thereafter, the lower rolls  22 ,  23  and  24  are moved upward by a predetermined height, while the upper rolls  12 ,  13  and  14  are moved downward by a predetermined height. The predetermined height of the lower rolls  22 ,  23 ,  24  and that of the upper rolls  12 ,  13 ,  14  are about several millimeters below the decimal. By moving the lower rolls  22 ,  23 ,  24  and the upper rolls  12 ,  13 ,  14  vertically from the state of  FIG. 3  it is possible to constitute a zigzag type roll straightener. The work  10  can be straightened by passing it between the upper rolls  11 ,  12 ,  13 ,  14 ,  15 ,  16 ,  17  and the lower rolls  21 ,  22 ,  23 ,  24 ,  25 ,  26 ,  27 .  
         [0029]     Thus, in the present invention, all of the upper and lower rolls are moved vertically (as the case may be the inlet- and outlet-side upper and lower rolls are not moved vertically) so that the invention can be applied to any one of both opposed type and zigzag type roll straighteners, but it is only the three lower rolls  22 ,  23  and  24  that are moved horizontally. In this way both opposed type and zigzag type roll straighteners can be fabricated while limiting the number of rolls which are moved horizontally to a small number, whereby the manufacturing cost can be reduced and the area of roll straightener installation in the factory concerned can be diminished.  
         [0030]     Next, with reference to  FIG. 4 , a description will be given about the structure of moving the lower rolls  22 ,  23  and  24  all together in the transverse direction. The lower rolls  22 ,  23  and  24  have respective rotating shafts  32 ,  33  and  34 , which are inserted respectively into holes  42 ,  43  and  44  formed in a support member  40 . A horizontal spacing between the holes  42  and  43  and a horizontal spacing between the holes  43  and  44  are each set at X. The holes  42 ,  43  and  44  are formed vertically long so that the rotating shafts  32 ,  33  and  34  can move vertically. Further, moving means for moving rotating means (not shown) for the lower rolls  22 ,  23  and  24  are fixed to the support member  40 . In case of switching from one to the other between the opposed type and the zigzag type, the lower rolls  22 ,  23  and  24  can be moved transversely by only moving the support member  40  with use of moving means (not shown) without the need of making a positional adjustment in the transverse direction of the lower rolls  22 ,  23  and  24 . In this way the opposed type and the zigzag type can be easily switched from one to the other. The support member  40  is used in the example, but it is not always necessary to use the support member  40 .  
         [0031]     Although in the above embodiment the lower rolls  22 ,  23  and  24  are moved in the transverse direction, the upper rolls  12 ,  13  and  14 , instead of the lower rolls  22 ,  23  and  24 , may be moved in the transverse direction. Further, although in the above embodiment seven pair of upper and lower rolls are used, there may be used five or nine or more odd-numbered pairs of upper and lower rolls. The reason why odd-numbered pairs are used is that one pair located on the middle position is to be made the vertex in the opposed type.