Patent Publication Number: US-2003226432-A1

Title: Gang saw system for rotating and segmenting a workpiece

Description:
RELATED APPLICATIONS  
       [0001] The application titled “CORE FOR WINDING MATERIAL AND METHOD FOR MANUFACTURING THE SAME”, having been filed concurrently with the present application, is hereby incorporated herein by reference.  
       TECHNICAL FIELD  
       [0002] The present invention relates to the introduction of a workpiece to a saw and, more particularly, relates to segmenting the workpiece into a plurality of portions, to be used as cores, upon which materials may be wound.  
       BACKGROUND OF THE INVENTION  
       [0003] The use of a core is widely used in many industries for the winding and unwinding of materials. A goal in each industry is to utilize a cost effective core in the manufacturing process. Also, each industry desires to utilize a core which has structural characteristics suitable for the particular material to be wound or unwound. Some materials require that the core, upon which it is wound, to have particular dimensional requirements as well as strength requirements. Moreover, some industries require that their cores not only be reusable, but be manufactured from readily available materials for cost effectiveness.  
       [0004] For example, aluminum producers typically require aluminum of a particular gauge and width be wound on a cardboard core. Although cardboard is cost effective to use, problems often occur which degrade the structural integrity of cardboard cores. One such problem is that cardboard cores are prone to shrinkage as a result of the changing moisture content in the cores. Another problem is that cardboard cores sometimes collapse because of insufficient strength. In response, some industries have attempted to utilize machined steel cores; but this is cost prohibitive. Moreover, the use of steel cores does not provided the desired dimensional requirements needed in most industries that utilizing some sort of winding or unwinding apparatus.  
       [0005] The cores upon which most materials are wound are typically circular with a hollow interior. Some industries require that the width and inner diameter of these cores have a particular dimension in order for the cores to be suitable for use with their winding or unwinding machines. However, manufacturing a core having the desired inner diameter, while utilizing readily available and cost effective materials, has proven difficult.  
       [0006] PVC (polyvinyl chloride) or some other thermoplastic resin, for example, is readily available and cost effective to use. Also, the structural integrity of the PVC is what is desired by the industry. However, PVC is typically manufactured in the form of elongated pipe having a substantial length. Thus, workpieces having a substantial length are often difficult to work with. Once the length of the PVC workpiece is cut to form a core of a particular width, the diameter of the core may be more easily resized into the desired configuration for use as a core. It is the dimensioning characteristic that makes PVC desirable to use.  
       [0007] Therefore, there is a need for a gang saw for cutting a readily available and cost effective workpiece, such as an elongated piece of PVC, into a plurality of cores. The saw must be able to receive and cut the workpiece into a plurality of portions having a particular configuration so that the cores may then be more easily resized, if desired, in a fast and cost effective manner.  
       SUMMARY OF THE INVENTION  
       [0008] The present invention solves the above-identified problem by providing a gang saw system for orienting and segmenting a workpiece. The workpiece is oriented in the gang saw system to facilitate the workpiece being segmented into cores.  
       [0009] Generally described, the present invention includes a support structure for supporting the workpiece relative a cutting assembly. In one embodiment, the cutting assembly includes an arbor having a plurality of spaced apart cutting blades. The workpiece is selectively moved toward the cutting assembly until the blades of the cutting assembly engage the workpiece. Alternatively, the cutting assembly is selectively moved toward the workpiece until the blades of the cutting assembly engage the workpiece.  
       [0010] According to one aspect of the invention, the workpiece is oriented into the cutting assembly to segment the workpiece into a plurality of portions commonly referred to as cores. Preferably, the workpiece is rotated into the blades so that each of the blades makes a continuous cut all the way around the workpiece.  
       [0011] The foregoing has broadly outlined some of the more pertinent aspects and features of the present invention. These should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Other beneficial results can be obtained by applying the disclosed information in a different manner or by modifying the disclosed embodiments. Accordingly, other aspects and a more comprehensive understanding of the invention may be obtained by referring to the detailed description of the exemplary embodiments taken in conjunction with the accompanying drawings, in addition to the scope of the invention defined by the claims. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0012]FIG. 1 illustrates a front view of one embodiment of the gang saw system of the present invention.  
     [0013]FIG. 2 illustrates an end view of the gang saw system depicted in FIG. 1.  
     [0014]FIG. 3 illustrates a front view of a structure for translating the workpiece into the gang saw system of FIG. 1.  
     [0015]FIG. 4 illustrates a close-up perspective view of a portion of the present invention wherein a workpiece is supported between a plurality of elongated rollers.  
     [0016]FIG. 5 illustrates a close-up perspective view of the cutting assembly cutting the workpiece.  
     [0017]FIG. 6 illustrates a plurality of cores manufactured in accordance with the present invention.  
    
    
     DETAILED DESCRIPTION  
     [0018] Referring now to the drawings in which like numerals indicate like elements throughout the several views, FIGS. 1 and 2 depict a gang saw system  10  for orienting and segmenting a workpiece  12  (FIGS. 3 and 4). The gang saw  10  includes a plurality of vertical members  20  and horizontal members  30  to define a structural framework with an interior space for supporting a cutting assembly  50  and a support structure  70  for handling the workpiece  12 .  
     [0019] Although the embodiments described herein are primarily directed toward the use of a PVC workpiece, the present invention contemplates the use of workpieces of any type of material in an elongated form, as shown in FIG. 3, which may be segmented into cores for winding a continuous web of material. The workpiece  12  is typically cylindrical with a hollow center there through. Preferably, the workpiece  12  is hollow PVC piping. However, the workpiece  12  may have any possible configuration suitable for being segmented into a plurality of cores for receiving a continuous web of material.  
     [0020] While any suitable material may be used, the vertical and horizontal members  20 ,  30  are preferably steel two by two inch box tubing. However, angle iron may also be used to provide structural support. As best shown in FIGS. 1 and 2, the vertical members  20  are laterally spaced apart from one another and the horizontal members  30  are laterally spaced apart from one another to define the interior space. The vertical and horizontal members  20 ,  30  are secured together with mechanical fasteners. Alternatively, the vertical and horizontal members  20 ,  30  may be suitably welded or otherwise secured to each other to provide a rigid framework. The width and height of the structural framework is dependent upon the desired scope of movement from the cutting assembly  50  and the support structure  70 , as described below.  
     [0021] Also, as shown in FIG. 3, the framework of the gang saw system  10  may be extended to include a table-like structure  32  for translating the workpiece  12  into the support structure  70 . The table-like structure  32  is preferably also assembled from additional vertical and horizontal members  20 ,  30 . Elongated free rollers  34  may also be included to keep the workpiece  12  properly aligned with the support structure  70 . In this embodiment, the workpiece  12  is slid along the length of the rollers  34  when being translated into the support structure  70 . The workpiece  12  is slid into the support structure  70  until the end of the workpiece  12  abuts a stop extending inward from the framework. Preferably, the stop is adjustable so that the extent which the workpiece  112  is received into the support structure  70  can be varied.  
     [0022] In the preferred embodiment, the support structure  70  is positioned over the cutting assembly  50  as shown in FIGS. 1 and 2. The cutting assembly  50  is preferably moveable toward the workpiece  12  held in the support structure  70  as shown in FIG. 4. However, the workpiece  12  may instead be moved toward the cutting assembly  50 . In such case, the workpiece  12  would be lowered to be engaged by the cutting assembly  50 . In another embodiment, both the cutting assembly  50  and the support structure  70  may be moved toward one another such that the workpiece  12  may be engaged by the cutting assembly  50 .  
     [0023] The cutting assembly  50  includes a motor  52  for driving an arbor  54 . Preferably the motor  52  is at least a three horsepower, rotational movement motor. A continuous belt  55  is placed between the motor  52  and the arbor  54 . The arbor  54  includes a plurality of circular saw blades  56  which are spaced equidistant apart from one another as shown in FIG. 3. The type of blade  56  required depends on the type of workpiece  12 . For example, diamond tipped blades are suitable for cutting PVC pipe.  
     [0024] The distance which each blade  56  is spaced from another adjacent blade  56  is dependent upon the width desired for each of the cores being manufactured. Preferably, the blades  56  are secured to the arbor  54  by collars  58 . Holes (not shown) are drilled in blade  56  and a corresponding collar  58  in order to join each blade  56  with the corresponding collar  58 . When the blades  56  with collars  58  are placed onto the arbor  54 , set screws (not shown) are tightened to secure each blade  56  at a desired position along the length of the arbor  54 .  
     [0025] The distance between each blade  56  on the arbor  54 , and thus the width of each core being manufactured, may be adjusted by loosening the set screws and repositioning the blades  56  along the length of the arbor  54  so that the distance between each blade  56  corresponds to the desired width of the cores to be manufactured. Alternatively, in order to prevent having to repeatedly adjust the distance between adjacent blades  56  on a single arbor when manufacturing cores of different widths, the arbor  54  having the blades  56  set to cut cores having one particular width may be removed from the gang saw system  10  and replaced with another arbor  54  having blades  56  preset to manufacture cores having a different width. Each different arbor  54  with blades  56  is commonly referred to as a blade arrangement.  
     [0026] The cutting assembly  50  further includes upper and lower planar members  60  and  62  which are supported in the framework by guide rods  64  and linear bearings  66 . The linear bearings  66  are secured to two pairs of opposing horizontal members  30   a . Preferably the horizontal members  30   a  are wider two by three inch box tubing in order to accommodate the width of the linear bearings  66 . FIG. 2 best illustrates one pair of upper and lower horizontal members  30   a  which obstruct the view of the opposing pair of upper and lower horizontal members  30   a  on the opposite side of the framework. The ends of the horizontal members  30   a  are secured between two pairs of opposing horizontal members  30   b . FIG. 1 best illustrates one pair of upper and lower horizontal members  30   b  which obstruct the view of the opposing pair of upper and lower horizontal members  30   b  on the opposite side of the framework. The horizontal members  30   a  are positioned inward toward the center of the framework relative the exterior of the framework due to the narrower dimensions of the upper and lower planner members  60 ,  62  which must be able to move up and down within the framework.  
     [0027] The upper ends of the guide rods  64  extend downward from the bottom of the upper planar member  60 . Each of the guide rods  64  pass through a pair of aligned linear bearings  66 . The upper and lower planar members  60 ,  62  are secured to each other at their corners by threaded rods  68 . As best shown in FIG. 1, the lower planar member  62  is suspended from the upper planner member  60  via threaded rods  68 .  
     [0028] Between the lower planar member  60  and the floor upon which the gang saw system  10  sits is a screw jack  80 . The screw jack  80  raises and lowers the upper and lower members  60 ,  62  as the guide rods  64  pass through the linear bearings  66 . The motor  52  is secured to the top of the lower member  62  and is raised and lowered along with the lower planar member  62 . The arbor  54  with blades  56  is secured upon the top of the upper member  60  with pillow blocks  82 . A portion  84  of box tubing may be used between the upper planar member  60  and the pillow blocks  82  to obtain sufficient clearance between the blades  56  and the upper planar member  60 . Thus, as the screw jack  80  raises the upper and lower planar members  60 ,  62 , the blades  56  are placed into contact with the workpiece in order to cut the workpiece. The blades  56  of the cutting assembly  50  may begin to rotate to cut the workpiece  12  before the blades  56  engage the workpiece  12  or, alternatively, the blades  56  may begin to rotate after they engage the workpiece  12 .  
     [0029] When the workpiece  12  is received in the support structure  70 , as best illustrated in FIG. 4, the workpiece  12  rests on top of a pair of elongated free rollers  86 . Note that the free rollers  86  are rotatably fixed to the framework in FIGS. 1, 2 and  4 . Because the free rollers  86  are fixed to the framework and the workpiece  12  on the rollers  86  does not get raised or lowered, the support structure  70  depicted in FIGS. 1, 2 and  4  is not considered to be selectively moveable.  
     [0030] Another pair of drive rollers  88  may be raised and lowered into contact with the workpiece  12  as the workpiece  12  rests on top of free rollers  86 . Because the drive rollers  88  are moveable relative to free rollers  86 , workpieces  12  with different diameters may be easily accommodated. A continuous belt  90  extends between the drive rollers  88  which are in turn driven by continuous belt  92  and motor  94 . The motor  94  sits on top of extension member  95  which extends laterally from member  96  in order to allow belt  92  to extend downward unobstructed.  
     [0031] Underneath member  96  is a scissors lift  98  which is used to raise and lower member  96 . The scissors lift  98  sits on top of one of the uppermost horizontal members  30 . In FIGS. 1 and 2, the scissors lift  98  is fully extended. Extending downward from the end of member  96  is vertically-oriented member  102  which is received to horizontal member  104 . One end of each of the drive rollers  88  is secured to the horizontal member  104 . The opposite end of each of the drive rollers  88  is secured to vertically-oriented member  106 . The uppermost end of the vertically-oriented member  106  is then secured to member  96 . Guide rods  108 , which extend upward from the uppermost horizontal member  30  to extend through member  96 , may be utilized to prevent swaying. The scissors lift  98  should be limited to up and down motion.  
     [0032] Alternatively, the rollers  86  may be fixed to an additional member which is also secured to the vertically-oriented member  102 , similar to the manner horizontal member  104  is secured, so that the free rollers  86  may be raised and lowered by the scissors lift  98  in combination with drive rollers  88 . In such case, the support structure  70 , with the workpiece  12  therein, would be selectively movable toward the cutting assembly  50 .  
     [0033] In operation, the horizontal member  30 , upon which the scissors lift  98  rests, remains in a fixed position. As the scissors lift  98  lowers the member  96  downward, the drive rollers  88  are lowered down onto the workpiece  12 . The workpiece  12  is then trapped between drive rollers  88  and free rollers  86 . The workpiece  12  should not be permitted to move from side to side or flex in order to maintain certain width tolerances required of cores. The motor  94  then allows the drive rollers  88  to rotate the workpiece  12 . The rotating blades  56  of the cutting assembly  50  are then raised to engage the rotating workpiece  12  and the workpiece is rotated into the rotating blades  56 .  
     [0034]FIG. 5 best illustrates rotating blades  56  engaging and cutting into the rotating workpiece  12 . The workpiece  12  is rotated more than one complete revolution in order to let each rotating blade  56  to simultaneously make a clean and continuous cut all the way around the periphery of the workpiece  12 . The more times the workpiece  12  is rotated, the clearer the cuts made into the workpiece  12  are. However, in one embodiment, the workpiece  12  may be rotated only one complete revolution to cut all the way around the periphery of the workpiece  12 . The multiple continuous cuts made into the workpiece  12  result in a plurality of cores  110  as shown in FIG. 6, which may then be used for winding a continuous web of material. Note that the portions of workpiece  12  between the cuts being made into the workpiece  12  remain free from contact from the blades  56 .  
     [0035] The use of the gang saw  10  as described above constitutes an inventive method of the present invention in addition to the gang saw  10  itself. In practicing the method of manufacturing a plurality of cores from a workpiece  12 , the steps include supporting the workpiece  12  relative a cutting assembly  50  as described above. The next step includes moving either the workpiece  12  in the support structure  70  or the cutting assembly  50  toward the other such that the cutting assembly  50  engages the workpiece  12 . Alternatively, both the support structure  70  with the workpiece  12  and the cutting assembly  50  may be moved toward each other. Next, the method includes segmenting the workpiece  12  into a plurality of portions by orienting the workpiece  12  relative the cutting assembly  50 . Preferably, the orienting step includes rotating the workpiece  12  into the cutting assembly  50  such that the cutting assembly  50  makes a plurality of separate and continuous cuts all the way around the workpiece  12 .  
     [0036] The method of the present invention may also include the step of replacing the arbor  54  and blades  56  with a different arbor  54  and blades  56  so that different cores having different widths may be more easily manufactured.  
     [0037] The present invention has been illustrated in relation to particular embodiments which are intended in all respects to be illustrative rather than restrictive. Those skilled in the art will recognize that the present invention is capable of many modifications and variations without departing from the scope of the invention. Accordingly, the scope of the present invention is described by the claims appended hereto and supported by the foregoing.