Abstract:
A capstan for handling slitting tools comprises a base, a pivoting frame, an outer frame and a plurality of shafts. The pivoting frame is supported by the base for pivotal movement about an axis. The outer frame is supported by the rotating frame for translational movement along the axis. The plurality of shafts extends from the outer frame transversely to the axis. The capstan preferably further includes an axial actuator for translating the outer frame relative to the pivoting frame along the axis. This permits an attendant to raise or lower the outer frame, and, hence, raise or lower the shafts. By thus raising or lowering the shafts, the attendant can adjust the height of the shafts to a comfortable level for loading or unloading knives and spacers without excessive lifting or bending. An optional pusher serves to automatically slide the tools between the capstan and the slitter machine.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to capstans for use in handling slitting tools for sheet metal slitter machines, and more particularly, to a novel capstan capable of vertical guided movement so as to permit its use at a height convenient to an attendant.  
           [0003]    2. Description of the Related Art  
           [0004]    A slitter machine uses rotary slitting knives or tools for cutting of sheet metal into strips. More specifically, a plurality of knives and spacers having center holes are slid onto arbors or shafts of the slitter machine. Typically, a slitter machine will include pairs of vertically-spaced arbors. Each arbor induces the knives to rotate as the arbor is turned. The rotating knives cut sheet metal into a plurality of “mults” as the sheet metal passes between the arbors. The arrangement of the knives and spacers on the arbors of the slitter machine must be changed when it is desired to change the number or relative sizes of the mults cut from the sheets passing between the arbors.  
           [0005]    A capstan is often used in removing and replacing the knives and spacers. Known capstans include a capstan frame and shafts or arbors which extend from the capstan frame in alignment with the arbors of the slitter machine. The knives and spacers can be slid either manually or mechanically between the shafts of the capstan and the arbors of the slitter machine.  
           [0006]    Known capstans typically include a plurality of pairs of shafts which are aligned vertically with the arbors of the associated slitter machine but which extend in different orientations from the capstan frame. This permits an attendant to load knives and spacers onto one pair of shafts while another pair of shafts is aligned to transfer knives and spacers onto, or off of, the arbors of the slitter machine.  
           [0007]    One drawback to such capstans relates to the alignment of the shafts with the corresponding arbors of the slitter. Very often, the heights of the shafts of the capstan are such that it is inconvenient for an attendant to load knives and spacers onto the shafts. Typically an attendant must lift the knives and spacers to load them onto an upper arbor and bend to load the knives and spacers onto a lower arbor. There remains a need in the art for a capstan designed to reduce the need for an attendant to have to repeatedly lift or bend in order to manipulate the tools on the capstan.  
         SUMMARY OF THE INVENTION  
         [0008]    This need and others are addressed by a capstan for handling slitting tools comprising a base, a pivoting frame, an outer frame and a plurality fo shafts extending from the outer frame. The pivoting frame is supported by the base for pivotal movement about an axis. The outer frame is supported by the pivoting frame for translational movement along the axis. The plurality of shafts extends from the outer frame transversely to the axis.  
           [0009]    The capstan further includes at least one axial actuator for raising and lowering the outer frame relative to the pivoting frame along the axis. The axial actuator permits an attendant to raise or lower the outer frame and thereby raise or lower the shafts to a convenient height for loading and unloading the knives and spacers. Optionally, the capstan includes a pivotal actuator for pivoting the pivot frame about the axis so as to align the shafts with arbors of an associated slitting machine.  
           [0010]    The preferred actuators may operate hydraulically, electrically, manually, pneumatically or by any other suitable means which may be known to those of ordinary skill in the art. In accordance with one embodiment of the invention, the pivoting actuator comprises a hydraulic motor having a shaft mounting a pinion gear. The pivoting frame preferably mounts a ring gear engaged by the pinion gear so as to permit the motor to turn the pivoting frame. In accordance with another embodiment, the axial actuator comprises an axial actuator cylinder mounted by the base and an axial actuator piston. The axial actuator piston is slidably received in the axial actuator cylinder such that the axial actuator cylinder restrains the axial actuator piston for translational movement parallel to the axis. The axial actuator piston is positioned so as to press against the outer frame to raise or lower the outer frame in response to fluid pressure in the axial actuator cylinder.  
           [0011]    Optionally, a pusher is provided to slide the knives and spacers between the shafts of the capstan and the arbors of the slitter machine. A preferred pusher comprises a pusher frame; a pusher plate; and a pusher actuator, most preferably hydraulic, for inducing the pusher plate to linear movement along one or more of the shafts of the capstan. Most preferably, the pusher includes one or more guide rod restraints and one or more guide rods constrained thereby to move linearly along the one or more shafts. One advantage of the optional pusher is that is relieves the attendant of the need to manually transfer the knives and spacers between the capstan and the slitter machine.  
           [0012]    Therefore, it is one object of the invention to provide a novel capstan capable of vertical translational movement so as to permit its use at a height convenient to an attendant. It is another object of the invention to provide for the automatic transfer of the knives and spacers between the capstan and the slitter machine. These and other objects, features and advantages of the present invention will be described in further detail in connection with preferred embodiments of the invention shown in the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of a capstan and an associate slitter machine with an attendant;  
         [0014]    [0014]FIG. 2 is a top plan view of the capstan and slitter machine of FIG. 2;  
         [0015]    [0015]FIG. 3 is a side sectional view of the capstan of FIG. 1;  
         [0016]    [0016]FIG. 4 is a side elevation view of an optional pusher for use with the capstan of FIG. 1; and  
         [0017]    [0017]FIG. 5 is a top plan of the pusher of FIG. 4. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]    As best shown in FIG. 1, a preferred capstan  10  includes a base  12 ; a pivoting frame  14  (FIG. 3); an outer frame  16 ; and a plurality of arbors or shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34  and  36 . The shafts  20 ,  22 ,  30 ,  32  are shown supporting knives and spacers  40 . The shafts,  20 ,  30  align with arbors or shafts  50  (only one shown) of a slitter machine  52  to permit an attendant  54  to slide the knives and spacers  40  between the shafts,  20 ,  30  and the arbors  50 . It will be seen from FIG. 1 that, when the shafts  20 ,  30  are aligned with the arbors  50  of the slitter machine  52 , the shaft  20  of the capstan  10  lies at an elevation which would require the attendant to lift the knives and spacers  40  to position the knives and spacers  40  on the shaft  20 . Likewise, when aligned with the lower of the two arbors  50 , the shaft  30  of the capstan  10  lies at an elevation which would require the attendant to bend in order to position the knives and spacers  40  on the shaft  30 .  
         [0019]    In the preferred embodiment shown in FIG. 2, the set of upper shafts  20 ,  22 ,  24 ,  26  is symmetrically arranged about the outer frame  16 . The same is true of the set of lower shafts  30 ,  32 ,  34 ,  36  (FIG. 1). The particular number and orientation of the shafts are not critical to the invention and may be varied as understood by those of ordinary skill in the art.  
         [0020]    As best shown in FIG. 3, the preferred base  12  includes a box portion  60  formed from welded steel and an upright metallic portion  62  defining an axis  64 . The upright metallic portion  62  mounts a coupling plate or collar  66  for engagement through an opening  68  in the outer frame  16 .  
         [0021]    The preferred pivoting frame  14  is in the form of a metal structure  70  including a mounting plate  72 . The mounting plate  72  mounts a ring gear assembly  74 .  
         [0022]    The pivoting frame  14  preferably is supported by the base  12  for pivotal movement about the axis  64 . Most preferably, the ring gear assembly  74  includes a thrust bearing  80 , shown as a roller bearing in FIG. 3, which pivotally supports the pivoting frame  14  while carrying the collective weight of the pivoting frame  14 ; the outer frame  16 ; the shafts  20 ,  22 ,  24 ,  25 ,  30 ,  32 ,  34 ,  36  (FIG. 1); and the knives and spacers  40 .  
         [0023]    Returning to FIG. 2, the preferred base  12  supports a pivoting actuator  90  which includes a conventional hydraulic motor  92  having a shaft  94  and a pinion gear  96  mounted on the shaft  94 . The pinion gear  96  engages the ring gear assembly  74  (FIGS. 1 and 3) for pivotal movement of the pivoting frame  14  in a manner well known to those of ordinary skill in the art. It will be appreciated that the use of a hydraulic motor  92  to turn the pivoting frame  14 , while preferred, is not critical to the invention and other types of rotary actuators, or manual rotation, may be used for the same purpose. As shown in FIG. 3, the preferred outer frame  16  includes a box portion  100  formed from welded steel. The box portion  100  supports the shafts  22 ,  26 ,  32 ,  36  (only four shown in FIG. 3).  
         [0024]    The preferred outer frame  16  is constrained to move along the axis  64 . In the preferred embodiment shown in FIG. 3, the outer frame  16  pivotally mounts a plurality of rollers  130 ,  132 ,  134  and  136  (only four shown in FIG. 3). The rollers  130 ,  132 ,  134 ,  136  fit over raised tracks  140  and  142  (only two shown in FIG. 3) positioned on an outer surface of the pivoting frame  14  to constrain the rollers  130 ,  132 ,  134 ,  136  to movement parallel to the axis  64 . Those skilled in the art will recognize that the constraining system shown, while preferred, is not critical to the invention and that other suitable means of constraint are within the ordinary skill in the art.  
         [0025]    The preferred base  12  supports at least one, and preferably two, axial actuators  150  (only one shown), each of which includes an axial actuator cylinder  152  supported by the base  12  and an axial actuator piston  156  at least partially received in the axial actuator cylinder  152 . A plurality of hardened inserts  158  (only one shown) preferably are secured to the outer frame  16  for alignment with the axial actuator piston  156  (only one shown). Most preferably, the axial actuator piston  156  (only one shown) responds to hydraulic pressure in the axial actuator cylinder  152  so as to induce raising or lowering of the outer frame  16  relative to the pivoting frame  14  along the axis  64  so as to adjust the height of the shafts  22 ,  26 ,  32 ,  36 . It will be appreciated that the use of a hydraulic pressure to move the outer frame  14 , while preferred, is not critical to the invention and other types of manual or powered actuators may be used for the same purpose.  
         [0026]    This feature permits the attendant  54  (FIG. 1) to raise or lower the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) to the level most comfortable for the attendant  54  (FIG. 1) when loading knives and spacers  40  (FIG. 1) onto the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1). Most preferably, the pivoting frame  14  and the outer frame  16  are constructed so as to provide a range of translational motion to the outer frame such that the level of the upper set of shafts  20 ,  22 ,  24 ,  26  (FIGS. 1 and 2) when the outer frame  16  is at is lowermost position is substantially the same as the level of the lower set of shafts  30 ,  32 ,  34 ,  36  (FIG. 1) when the outer frame  16  is at its uppermost position.  
         [0027]    The pivoting actuator  90  (FIG. 2) and the axial actuator  150  (FIG. 3) preferably are regulated by a controller (not shown), such as an electronic, hydraulic or pneumatic controller, in a manner within the ordinary skill in the art. Most preferably, the axial actuator piston  156  (FIG. 3) retracts away from the outer frame  16  before the motor  92  (FIG. 2) is operated and the pivoting frame  14  is pivoted about the axis  64  (FIG. 3). Conventional switches (not shown), such as push button switches or foot pedals, are provided to allow the attendant  54  (FIG. 1) to initiate and control the movement of the pivoting and axial actuators  90  (FIG. 2),  150  (FIG. 3). Nevertheless, the controller (not shown) is not critical to the present invention.  
         [0028]    As shown in FIG. 3, the preferred base  12  additionally supports a detent system  160  for limiting the pivotal movement of the pivoting frame  14 . More specifically, the base  12  mounts a shelf  162  which, in turn, supports a detent cylinder  164  and a detent piston or detent  166 . The detent cylinder  164  at least partially receives the detent  166 . The detent  166  includes a cam roller  168  pivotally mounted at an end opposite the detent cylinder  164 . The detent  166  moves the cam roller  168  into engagement with lips  170  aligned with the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) so as to limit the pivotal movement of the pivoting frame  14 . Most preferably, a controller (not shown) detects the orientation of the pivoting frame  14  and actuates the detent  166  at the proper time to engage the lips  170 . Those skilled in the art will recognize that the constraining system shown, while preferred, is not critical to the invention and that other suitable means of constraint are within the ordinary skill in the art.  
         [0029]    More specifically, the set of shafts  20 ,  22 ,  24 ,  25  (FIGS. 1 and 2) are arranged symmetrically about the axis  64  (FIG. 3) such that the set of pivotal movements of the pivotal frame  14  which result in alignment of one of the shafts  20 ,  22 ,  24 ,  25  (FIGS. 1 and 2) with the corresponding arbor  50  (FIGS. 1 and 2) of the associated slitter machine  52  (FIGS. 1 and 2) form a symmetry group with respect to the operation of pivotal movement. The interaction of the detent cylinder  164  (FIG. 3) and the detent  166  (FIG. 3) with the lips  170  (FIG. 3) on the pivoting frame  14  limits the permissible pivotal movements of the pivoting frame to this symmetry group. That is, the engagement of the detent cylinder  164  and the detent  166  with the pivoting frame  14  has the effect of limiting the pivotal movement of the pivoting frame  14  to movements which culminate in the alignment of one of the shafts  20 ,  22 ,  24 ,  26  (FIGS. 1 and 2) with the alignment direction of the corresponding shaft  50  (FIGS. 1 and 2) of the slitter machine  52  (FIGS. 1 and 2).  
         [0030]    [0030]FIG. 4 shows an optional pusher  180  for use with the preferred capstan  10  (FIGS.  1 - 3 ). The pusher  180  includes a pusher frame  182  and a coupling plate or collar  184  affixed to the pusher frame  182  for coupling with the plate or collar  66  (FIG. 3) of the base  12  (FIG. 3) of the capstan (FIGS.  1 - 3 ).  
         [0031]    The preferred pusher  180  uses a pusher actuator  190  engaged with a pusher plate  192  to slide knives and spacers  40  (FIG. 1) along the shafts  10 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1). As best shown in FIG. 5, the pusher actuator  190  includes a pusher cylinder  194  pivotally mounted to the pusher frame  182  and a pusher piston  196  at least partially received in the pusher cylinder  194 . The pusher piston  196  is coupled to the pusher plate  192  so as to induce the pusher plate  192  to move in response to pressure (preferably hydraulic pressure) in the pusher cylinder  194 . Most preferably, the pusher plate  192  includes a cut-out (not shown) so as to allow the pusher plate  192  to fit over the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  26  (FIG. 1) and press against the knives and spacers  40  (FIG. 1) symmetrically on either side of a pair of shafts  20 ,  30 ;  22 ,  32 ;  24 ,  34 ;  26 ,  36  (FIG. 1). Those skilled in the art will appreciate that the configuration of the pusher plate  192  is not critical to the present invention and that various configurations are available without departing from the scope of the invention.  
         [0032]    The preferred pusher  180  further includes a pair of guide rods  210  and  212 ; a pair of guide restraints  214  and  216 ; and a pair of connecting rods  218  and  220 , which cooperate to regulate the movement of the pusher plate  192 . The guide rods  210 ,  212  are received in the guide rod restraints  214 ,  216 , respectively, so as to constrain the guide rods  210 ,  212  so as to move only in a direction perpendicular to the axis  64  (FIG. 3) along a pair of the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1). End portions of the guide rods  210 ,  212  and the connecting rods  218 ,  220  are coupled to the pusher plate  192  so as to constrain the pusher plate  192  to linear motion along one or more shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1). Those skilled in the art will appreciate that the means of constraining the pusher plate  192  to linear motion along the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) is not critical to the present invention.  
         [0033]    One advantage of the optional pusher  180  (FIGS. 4 and 5) is that is serves automatically to slide the knives and spacers  40  (FIG. 1) between the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) of the capstan  10  and the arbors  50  (FIG. 1) of the slitter machine  52  (FIG. 1). The pusher  180  (FIGS. 4 and 5) is of a particularly simple configuration, capable of tooling movement only in a single direction.  
         [0034]    From the foregoing, it will be seen that the preferred capstan (FIGS.  1 - 3 ) advantageously provides for the raising and lowering of the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1). This permits an attendant  54  (FIG. 1) to load knives and spacers  40  (FIG. 1) onto each of the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) while that shaft is at a convenient height, and then to adjust the height of the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) so as to align with the corresponding arbors  50  (FIG. 1) of the associated slitter machine  52  (FIG. 1). The optional pusher  180  (FIGS. 4 and 5) serves to slide the knives and spacers  40  (FIG. 1) automatically between the shafts  20 ,  22 ,  24 ,  26 ,  30 ,  32 ,  34 ,  36  (FIG. 1) of the capstan  10  and the arbors  50  (FIG. 1) of the slitter machine  52  (FIG. 1), thereby relieving the attendant  54  (FIG. 1) of the need to manually transfer the knives and spacers  40 .  
         [0035]    Various changes or modifications in the invention described may occur to those skilled in the art without departing from the true spirit or scope of the invention. The above description of preferred embodiments of the invention is intended to be illustrative and not limiting, and it is not intended that the invention be restricted thereto but that it be limited only by the true spirit of and scope of the appended claims.