Abstract:
A metal punch assembly includes a member that defines a plurality of grooves as a locating feature for placement on a metal sheet and to restrict movement of the punch assembly to ensure accurate placement of holes in the sheet. A plurality of punches are movably connected to the member and are translatable from a retracted position to an extended position in which they form holes in the metal sheet. A corresponding method is also provided.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/183,173, filed Jun. 22, 2015, and which is hereby incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    This disclosure relates to punches for forming holes in metal sheets. 
       BACKGROUND 
       [0003]    Metal sheets are often used in building construction, such as to form roofs or walls. The metal sheets are typically attached to a frame or roof beams by fasteners such as nails or screws that must pass through the metal sheet. Accordingly, proper placement of the fasteners through the sheet is necessary to ensure that the fasteners properly engage the underlying roof beams. The metals sheets often have elongated, parallel ridges formed therein to provide structural integrity. 
       SUMMARY 
       [0004]    A metal punch assembly for use with a ridged metal sheet includes a base member and a plurality of punches. The base member has an outer surface that defines a plurality of parallel grooves. Each of the punches has a head, a sharp tip, and a shaft interconnecting the respective tip and respective head. Further, each of the punches is operatively connected to to the base member such that each of the punches is linearly translatable between a respective retracted position and a respective extended position relative to the base member. 
         [0005]    The apparatus improves upon the prior art by enabling the accurate and efficient formation of holes in a metal sheet. More specifically, the grooves formed by the base member are engageable with the ridges on the sheet so that the motion of the apparatus is limited to translation in two opposite directions. That is, interaction between the surface forming the grooves and the surface forming the ridges prevents lateral motion of the apparatus relative to the metal sheet while permitting movement in the direction of the ridges, thereby insuring that holes are formed linearly. 
         [0006]    The punches are movable to their extended positions through linear translation, which enables the punches to be struck with a hammer or other hand tool or striking implement to form the holes, thereby providing a light-weight and cost-effective system for forming the holes. The plurality of punches enables the formation of multiple holes when the assembly is at any given position relative to the metal sheet. Further, the assembly may be slid along the sheet to multiple positions relative to the metal sheet, where multiple holes may again be formed, further increasing efficiency and accuracy of hole placement. A corresponding method is also provided. 
         [0007]    The above features and advantages and other features and advantages of the present disclosure are readily apparent from the following detailed description of the best modes for carrying out the disclosure when taken in connection with the accompanying drawings 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic, perspective, exploded view of a metal punch assembly in accordance with the claimed invention; 
           [0009]      FIG. 2  is a schematic, perspective view of the metal punch assembly of  FIG. 1 ; 
           [0010]      FIG. 3  is a schematic, side view of the metal punch assembly of  FIGS. 1 and 2 ; 
           [0011]      FIG. 4  is a schematic, perspective view of the metal punch assembly of  FIGS. 1-3  engaging a metal roof panel; 
           [0012]      FIG. 5  is a schematic, cross-sectional side view of the metal punch assembly of  FIGS. 1-4  with a metal punch in a first, retracted position; 
           [0013]      FIG. 6  is a schematic, cross-sectional side view of the metal punch assembly of  FIG. 5  with the metal punch in a second, extended position; 
           [0014]      FIG. 7  is a schematic, top view of the metal punch assembly in a first position relative to the metal sheet; 
           [0015]      FIG. 8  is a schematic, top view of the metal punch assembly in a second position relative to the metal sheet; 
           [0016]      FIG. 9  is a schematic, top view of the metal punch assembly in a third position relative to the metal sheet; 
           [0017]      FIG. 10  is a schematic, perspective view of an alternative metal punch assembly within the scope of the claims; 
           [0018]      FIG. 11  is a schematic, cross-sectional, side view of the the metal punch assembly of  FIG. 10 ; 
           [0019]      FIG. 12  is a schematic, top view of a bushing shown in  FIG. 11 ; 
           [0020]      FIG. 13  is a schematic, cross-sectional side view of an alternative spacing member; and 
           [0021]      FIG. 14  is schematic top view of the alternative spacing member of  FIG. 20 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Referring to the Figures, wherein like reference numbers refer to like components throughout, a sheet metal punch assembly  10  is schematically depicted. The punch assembly  10  is configured to punch holes in a metal sheet, such as the one shown at  12  in  FIGS. 3-6 . Referring specifically to  FIGS. 1 and 2 , the punch assembly  10  includes a base member  14  having an outer surface, which includes a first outer surface portion  18  and a second outer surface portion  22 . The first outer surface portion  18  and the second outer surface portion  22  are on opposite sides of the base member  14  from one another. The first outer surface portion  18  is generally planar in the embodiment depicted, though the first outer surface portion may be characterized by contours or other geometry within the scope of the claims. The second outer surface portion  22  defines a plurality of parallel grooves  26 A,  26 B. It should be noted that, although the base member  14  depicted is characterized by a single piece of material, a base member may include a plurality of pieces operatively interconnected within the scope of the claimed invention. 
         [0023]    The punch assembly  10  also includes a plurality of punches  30 . The punch assembly  10  in the embodiment depicted includes four punches  30 . Each of the punches  30  includes a respective shaft portion  34 , a head  38 , and a tapered or conical end  42  terminating at a sharp tip  46 . The punches  30  are movably mounted with respect to the base member  14 . More specifically, the base member  14  defines four passageways  50 , i.e., holes, each of which extends through the base member  14  from the first outer surface portion  18  to the second outer surface portion  22 . Each of the punches  30  is partially disposed within a respective one of the passageways  50 . 
         [0024]      FIGS. 5 and 6  depict one of the punches  30  disposed in one of the passageways  50 , and are representative of all of the passageways  50  and punches  30 . Referring specifically to  FIGS. 5 and 6 , the base member  14  in the embodiment depicted is not solid but instead defines a plurality of chambers  54  therein. Accordingly, the passageways  50  are at least partially coextensive with portions of chambers  54 . The presence of the chambers  54  decreases the mass of the base member  14  compared to a solid base member. However, and within the scope of the claimed invention, the base member  14  may be substantially solid to make the base member  14  stronger and more rigid. If a generally solid base member is employed, the passageways  50  may, for example, be cylindrical borings. 
         [0025]    Referring again to  FIG. 1 , the punch assembly  10  in the embodiment depicted includes four bushings  58 , each of which is disposed within a respective one of the passageways  50  and extends through one of the chambers  54 . Each of the punches  30  extends through a respective one of the bushings  58  to assist in limiting movement of the punches  30  relative to the base member  14 . More specifically, and with reference to  FIGS. 5 and 6 , the inner diameter of each bushing  58  is marginally larger than the outer diameter of each punch  30 , and thus each punch  30  is limited to substantially linear movement (relative to the base member) along the center line of its respective bushing  58 . However, rotation of the punch  30  about the center line of the bushing is possible, but not necessary, during movement of the punch  30  between its extended and retracted positions, and thus the punch  30  is linearly translatable between the extended and retracted positions. The bushings  58  in the embodiment shown are connected to the base member  14  by adhesive bonding or by friction. 
         [0026]    The punch  30  is shown in a first, i.e., retracted, position relative to the base member  14  in  FIG. 5 . In the first position, the punch  30  is disposed such that the end  42  and tip  46  do not extend outside the passageway  50 , as shown in  FIG. 5 , or, alternatively, do not extend far outside the passageway  50 , and the head  38  is outside the passageway  50  on the side of the base member  14  defined by the first outer surface portion  18 . The punch assembly  10  includes four coil springs  60 . The shaft  34  of each punch  30  extends through a respective one of the coils springs  60  such that each of the coil springs  60  is disposed between the first outer surface portion  18  and a respective head  38  of one of the punches  30 . Accordingly, each coil spring  60  contacts the first outer surface portion  18  and a head  38  of a punch  30 , thereby biasing the punch  30  in its first position relative to the base member  14 . The spring  60  is in an unstressed state in  FIG. 5 . 
         [0027]    The punch  30  is movable to its second, i.e., extended, position relative to the base member  14  by exerting a force on the head  38  to overcome the bias of the spring  60 . Each head  38  in the first position is unobstructed such that it can be hit with a hammer  64  or other striking instrument to move the punch  30  to the second position, as shown in  FIG. 6 . As used in the claims, a “hammer” includes any striking instrument or tool. Referring specifically to  FIG. 6 , the tip  46  of the punch  30  extends further from the second outer surface portion  22  in the second position than in the first position. When the punch assembly  10  is engaged with the metal sheet  12 , as shown in  FIGS. 5 and 6 , the second outer surface portion  22  contacts the sheet  12 , and the movement of the punch  30  to the second position causes the tip  46  to protrude from the passageway  50 , past surface portion  22 , and thereby piercing the sheet  12  and forming a hole  66  in the metal sheet  12 . 
         [0028]    The punch assembly  10  improves upon the prior art by enabling sufficient force and energy to be applied to the punches  30  (by striking the heads  38  of the punches  30  with a hammer or other instrument) so that the punches  30  can form an actual hole in the metal sheet, which facilitates the insertion of a screw or other fastener when connecting the sheet  12  to a roof or other structure. Furthermore, multiple sheets  12  may be processed at once. For example, a second metal sheet, shown in phantom at  12 A, may be punched at the same time that metal sheet  12  is punched by placing the second metal sheet  12 A directly under metal sheet  12 . 
         [0029]    The punches  30  are retained relative to the base member  30  by the heads  38 , which have a larger diameter than the passageways  50  and the bushings  58 , and by o-rings  62 . Each punch  30  defines an annular groove  61  in its respective shaft portion  34 . A respective o-ring  62  is disposed within the annular groove  61  of each punch  30 . The o-rings  62  have an outer diameter larger than the inner diameter of the bushings  58 . 
         [0030]    Referring again to  FIGS. 1-4 , the punch assembly  10  also includes a spacing member  70 , which, in the embodiment depicted, is a flat, rectangular rod  74 . The rod  74  is movably mounted with respect to the base member  14 , and, more specifically, the rod  74  is rotatably connected to the base member  14  by a bolt  78 . The base member  14  defines a hole  82  in the first outer surface portion  18 , and the rod  74  defines a hole  86  at one end of the rod  74 . The bolt  78  extends through both hole  86  and hole  82  and engages the base member  14  to secure the rod  74  to the base member  14  such that the rod  74  is selectively pivotable or rotatable with respect to the base member  14  about an axis that is coextensive with the center line of the bolt  78 . 
         [0031]    The rod  74  defines another hole  90  at the end opposite hole  86 . The base member  14  defines another hole  94  in the first outer surface portion  18 . Another bolt  98  is secured to the rod  74  through hole  90 . Hole  94  is positioned such that the bolt  98  is inserted therein when the rod  74  is in a retracted or stored position relative to the base member  14 , as shown in  FIGS. 3 and 4 . The interaction between the bolt  98  and the base member  14  inside hole  94  retains the rod  74  in the retracted or stored position. To move the rod  74  from the stored or retracted position, the rod  74  must be elastically bent to remove the bolt  98  from the hole  94 . 
         [0032]    The passageways  50  are aligned with one another such that the punches  30  are arranged along a straight line. The punches  30  are spaced from one another to create holes in the metal sheet  12  that are spaced apart from one another in the same manner that roof beams are spaced apart from one another so that when the metal sheet  12  is placed on a roof, each of the holes formed in the metal sheet  12  is aligned with a respective roof beam. 
         [0033]    The grooves  26 A,  26 B are configured to position the punch assembly  10  relative to the metal sheet  12  so that the punches  30  are properly positioned relative to the metal sheet to punch holes in desired locations. More specifically, and with reference to  FIGS. 3-4 and 7 , the metal sheet  12  is generally flat and planar with the exception of elongated protuberances, i.e., ridges  102 A,  102 B, in the surface  106  of the sheet  12 . The ridges  102 A,  102 B are parallel to one another and are ridges that extend substantially from one end  110  of the sheet  12  to the other end  114  of the sheet  12 . Similarly, grooves  26 A,  26 B in the base member  14  extend from one end  118  of the base member  14  to the opposite end  122  of the base member  14 . 
         [0034]    The grooves  26 A,  26 B are sufficiently sized, shaped, and positioned such that, when the punch assembly  10  is sufficiently positioned with respect to the sheet  12 , each ridge  102 A extends into a respective one of the grooves  26 A, and each ridge  102 B extends into a respective one of the grooves  26 B. It should be noted that, within the scope of the claims, a metal sheet  12  may have more ridges than the punch assembly has grooves, and accordingly not every ridge will extend into a groove. Furthermore, and within the scope of the claims, a groove may contain more than one ridge. Accordingly, as used in the claims, each of said grooves at least partially containing a respective one of the ridges includes containing one or more ridges. 
         [0035]    When the ridges  102 A,  102 B are disposed within respective grooves  26 A,  26 B, the punch assembly  10  is selectively slidable across the surface of the metal sheet  12  in two opposing directions  126 ,  130 . However, movement of the punch assembly  10  laterally relative to the metal sheet  12  (i.e., in either direction  134  or  138 , which are perpendicular to directions  126 ,  130 ) is limited or prevented. More specifically, and with reference to  FIG. 3 , outer surface portion  22  includes segments  132 A,  132 B that generally face direction  134 , and segments  136 A,  136 B that generally face direction  138 . Segments  132 A,  132 B and  136 A,  136 B define lateral surfaces of grooves  26 A,  26 B, respectively. Surface  106  of sheet  12  includes segments  142 A,  142 B that generally face direction  134 , and segments  146 A,  146 B that generally face direction  138 . Segments  142 A,  142 B and  146 A,  146 B define lateral surfaces of ridges  102 A,  102 B, respectively. Contact between surface segments  132 A and  146 A, and between  132 B and  146 B prevents movement of the punch assembly  10  in direction  138 ; similarly, contact between surfaces  136 A and  142 A, and between  136 B and  142 B prevents movement of the punch assembly  10  in direction  134 . In other words, the surfaces defining the lateral edges of the grooves  26 A,  26 B interact with the surfaces defining the lateral edges of the ridges  102 A,  102 B to prevent lateral (i.e., perpendicular to the ridges  102 A,  102 B) movement of the punch assembly  10  relative to the sheet  12 . 
         [0036]      FIGS. 7-9  schematically depict a method of using the punch assembly  10 . The method includes placing the punch assembly  10  in a first position with respect to the metal sheet  12 , as shown in  FIG. 7 . In the first position, the edge  118  of the punch assembly  10  is aligned with, parallel to, and adjacent to the edge  110  of the metal sheet  12 ; each of the grooves  26 A has a corresponding one of the ridges  102 A at least partially disposed therein; each of the grooves  26 B has a corresponding one of the ridges  102 B at least partially disposed therein; and at least a portion of surface  106  of the metal sheet  12  contacts at least part of the outer surface portion  22  of the base member  14 , as shown in  FIG. 7 . 
         [0037]    The spacing member  70  (i.e., rod  74 ) is in its retracted or stored position in  FIG. 7 . The method also includes hitting each of the heads  38  of the four punches  30  with a hammer (shown at  64  in  FIG. 6 ) or other striking tool when the punch assembly  10  is in the first position. Hitting each of the heads  38  includes hitting or striking each of the heads  38  with sufficient force such that each of the punches  30  moves to its respective extended position and thereby punctures the sheet  12  to make a respective hole  66  therein. The holes formed by striking the heads  38  when the assembly  10  is in the first position are shown at  66  in  FIG. 8 . 
         [0038]    The method further includes sliding the punch assembly  10  along the surface  106  of the metal sheet  12  in direction  126  to a second position, as shown in  FIG. 8 . Referring to  FIG. 8 , sliding the punch assembly  10  to the second position includes moving the rod  74  from its retracted or stored position, and aligning bolt  98  with a reference feature in the metal sheet  12 , such as one of the holes  66  formed when the punch assembly  10  was in its first position. The rod  74  is configured such that, when the bolt  98  is aligned with, or adjacent to, one of the previously punched holes  66 , as shown in  FIG. 8 , the punch assembly  10 , which has not been moved laterally relative to the metal sheet  12 , is in the second position and ready to punch another row of holes. 
         [0039]    Accordingly, the method further includes hitting or striking each of the heads  38  with sufficient force to cause each of the punches  30  to puncture the sheet  12  and thereby create a respective hole  66  when the punch assembly is in the second position, as show in  FIG. 8 . The holes  66  formed when the punch assembly  10  is in the second position are shown in  FIG. 9 . 
         [0040]    The process is of sliding the punch assembly  10  to another position relative to the metal sheet  12  is repeated until all desired holes are formed in the sheet. For example, the method may include sliding the punch assembly  10  along surface  106  to a third position. The punch assembly  10  is in the third position when the bolt  98  is aligned with, or adjacent to, one of the holes  66  formed when the punch assembly  10  was in the second position. Each of the heads  38  are struck when the punch assembly  10  is in the third position to create another row of holes in the metal sheet  12 . 
         [0041]    It should be noted that the dimensions of the embodiment depicted are merely examples and may vary within the scope of the claimed invention. It should also be noted that the punch assembly  10  could include two or more punches within the scope of the claimed invention. The quantity of punches may vary with, for example, the width of the metal sheets being used and the number of holes desired to be punched in the metal sheets. It should be further noted that, although the sheet  12  shown and described is a metal roof panel, any metal sheet, such as metal siding or other building component, could be used within the scope of the claimed invention. 
         [0042]    Referring to  FIG. 10 , an alternative punch assembly embodiment is schematically depicted. Base member  214  is substantially similar to the base member  14 , but the second outer surface portion  222  defines grooves  226 A,  226 B that are differently sized and shaped compared to the grooves  26 A,  26 B. More specifically, grooves  226 A are sized the at least partially contain two of the ridges  102 A in the metal sheet. Further, the punch assembly of  FIG. 10  includes two spacing members  272  rotatably connected to the base member  214  so that the assembly is usable in two different directions. Optional handles  240 ,  248  are mounted to the base member  214  for ease of handling during operation or transportation. Passageways  250  extend through the base member  214  from the first outer surface portion  218  to the second outer surface portion  222 , but have a different configuration than passageways  50 . 
         [0043]    More specifically, and with reference to  FIG. 11 , passageway  250  includes a first portion  254  and a second portion  258 . The first portion  254  is characterized by a smaller diameter than the second portion  258 ; the diameter of the first portion is slightly larger than the diameter of the shaft portion  34  of the punch  30 . Each punch  30  has a respective bushing  262  connected thereto. More specifically, the inner diameter  270  of the bushing  262  is threaded, and the shaft portion  34  of each punch is threaded (not shown). The shaft portion  34  is threaded through the inner diameter of the bushing  262  so that the bushing  262  moves with the punch from its retracted position to its extended position. The bushing is disposed within passageway portion  258 . The diameter of passageway portion  258  is slightly larger than the outer diameter of the bushing  262  so that movement of the bushing relative to the base member  214  is substantially limited to linear translation. Referring to  FIG. 12 , the bushing is generally cylindrical with portions of the outer diameter  264  forming arcs. Flat portions  266  of the outer surface are formed to facilitate rotation of the bushing relative to the punch  30  when the threads are being engaged. As shown in  FIG. 11 , base member  214  is substantially solid, i.e., it does not include internal chambers such as those shown at  54  in  FIGS. 5 and 6 . 
         [0044]    Referring to  FIGS. 13 and 14 , an alternative spacing member  272  is schematically depicted. The spacing member  272  includes a first rod  270  that has a C-shaped cross-section which forms a channel. A second, flat rod  274  is disposed within the channel so that that rod  274  is selectively translatable relative to the first rod  270 . Rod  270  defines a hole through which fastener  78  rotatably mounts the first rod  270  to the base member  214 , and rod  274  has fastener  98  attached thereto for insertion into a hole formed in the first outer surface portion  218 , similar to the hole shown at  94  in  FIG. 1 . Accordingly, the length of the spacing member  272  is selectively variable by sliding rod  274  relative to rod  270 , such as to the position shown in phanton at  274 A in  FIG. 14 . A locking feature (not shown) may be employed to lock the rod  274  relative to rod  270 . 
         [0045]    While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.