Abstract:
A device for cutting a substrate including a frame with a first cutting mechanism operatively connected to the frame. The first cutting mechanism is slidable in a first direction relative to the frame. The device further includes a second cutting mechanism operatively connected to the frame, which is slidable in the first direction as well as slidable in a second direction relative to the frame. The second direction is substantially perpendicular to the first direction. The first and second cutting mechanisms are adjustable to select a desired cut depth and a thickness of a substrate such that the frame may be moved along an edge of the substrate to remove excess material from the substrate.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 60/895159, filed on Mar. 16, 2007, which is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a device for cutting sheetrock or similar material. More particularly, the present invention relates to a device for cutting sheetrock wherein the device may be adjusted vertically and horizontally so that a piece of sheetrock may be cut at a desired location by sliding the device across the edge of the sheetrock. 
       BACKGROUND OF THE INVENTION 
       [0003]    Traditional methods for cutting sheetrock are difficult, time-consuming, and prone to error. First, the person cutting the sheetrock has to measure the location to be cut at several points so that an accurate and straight cut can be made. Then, the cut needs to be made. Any error in measurement or cutting renders the sheetrock unusable, which increases costs. 
       SUMMARY OF THE INVENTION 
       [0004]    An object of the present invention is to provide a device for cutting sheetrock. 
         [0005]    An additional object of the present invention is to provide a device for cutting sheetrock that creates more accurate cuts and is less time-consuming than traditional methods. 
         [0006]    It is yet another object of the present invention to provide a device for cutting sheetrock that creates accurate cuts and saves time through the use a device that may be adjusted vertically and horizontally. 
         [0007]    It is an additional object of the present invention to provide a device for cutting sheetrock that may be slid across an edge of a piece of sheetrock to remove the edge. 
         [0008]    An embodiment of the inventive device includes a frame with a first cutting mechanism operatively connected to the frame. The first cutting mechanism is slidable in a first direction relative to the frame. The device further includes a second cutting mechanism operatively connected to the frame, which is slidable in the first direction as well as slidable in a second direction relative to the frame. The second direction is substantially perpendicular to the first direction. The first and second cutting mechanisms are adjustable to select a desired cut depth and a thickness of a substrate such that the frame may be moved along an edge of the substrate to remove excess material from the substrate. 
         [0009]    These and other objects of the present invention will be better understood in view of the Figures and preferred embodiment described. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of a device for cutting sheetrock according to an embodiment of the present invention. 
           [0011]      FIG. 2  is a partially sectioned, perspective view of a device for cutting sheetrock, according to another embodiment of the present invention. 
           [0012]      FIG. 3  is an exploded view of the device for cutting sheetrock shown in  FIG. 1 . 
           [0013]      FIG. 4  is an exploded view of the device for cutting sheetrock shown in  FIG. 2 . 
           [0014]      FIG. 5  is a perspective view of an ergonomic handle usable with the embodiments of  FIGS. 1 and 2 . 
           [0015]      FIG. 6  is a front view of a panel of sheetrock placed within the devices of  FIGS. 1 and 2 . 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0016]      FIG. 1  shows one embodiment of the present invention, a device  10  for cutting sheetrock. The device  10  includes a substantially U-shaped frame  12  having a bridge portion  14  and parallel arms  16  that extend horizontally from the bridge portion  14 . An adjustable post  18  and a movable post assembly  19  are assembled to the frame  12 . 
         [0017]    The bridge portion  14  defines an rectangular opening  13  for receiving the adjusting post  18 . The bridge portion  14  also includes a threaded aperture or hole  20  (best shown in  FIG. 3 ) extending from an inner surface or face of the opening outward to an outer surface of the bridge portion  14 . 
         [0018]    Each of the parallel arms  16  has a horizontal ridge  22 . In one embodiment, each horizontal ridge  22  extends from the bridge portion  14  to a free end of the corresponding parallel arm  16 . Each of the parallel arms  16  has a slot  24  coincident with the horizontal protrusion or ridge  22 . Each slot  24  is marked with measurements for indicating a horizontal distance of the movable post assembly  19  from the adjusting post  18 . 
         [0019]    When received in the opening of the bridge portion  14 , the adjusting post  18  is slidably movable perpendicular to the parallel arms  16 . The adjusting post  18  carries a first blade  26  and is marked with measurements to indicate the vertical position of the first blade  26  relative to the parallel arms  16 . The adjusting post  18  includes a vertical adjuster  28  for securely positioning the first blade  26  relative to the frame  12 , so that the first blade  26  will score or cut the sheetrock at a first desired position. Preferably, as shown in  FIGS. 1 and 2 , the first blade  26  is rotatably mounted to the post  18  by a screw or similar threaded fastener. Optimally, the cutting edge of the first blade  26  protrudes from the adjusting post  18  about one-sixteenth of an inch ( 1/16″), as best shown in  FIG. 1 . Alternatively, the first blade  26  may be fixedly mounted to the post  18 , or may be formed integral with the post  18 . 
         [0020]    In a simple embodiment of the vertical adjuster  28 , the hole  20  is a threaded hole and the threaded post of the dial  34  is movable toward and away from the adjusting post  18  by rotation of the threaded post in the threaded hole  20 , thereby clamping or releasing the adjusting post  18  for vertical sliding motion within the opening  13  of the bridge portion  14 . 
         [0021]    In another embodiment, the vertical adjuster  28  includes a vertical T-grooved slot (not shown), a nut housed in the slot and slidably movable along the slot, and the vertical-adjust dial  34  having a threaded post extending through the hole  20  of the bridge portion  14 . When the adjusting post  18  is received between the parallel arms  16 , the T-grooved slot is aligned with the hole  20  and the threaded post of the vertical-adjust dial  34  accordingly cooperates with the threads of the nut to clamp the adjusting post  18  against the bridge portion  14  of the frame  12  by action of the nut in the slot. Thus, when the vertical-adjust dial  34  is operated to clamp the adjusting post  18 , the first blade  26  is securely positioned relative to the parallel arms  16 . When the vertical-adjust dial  34  is operated to release the adjusting post  18 , the first blade  26  is slidably vertically movable perpendicular to the parallel arms  16 . 
         [0022]    In yet another embodiment, the vertical adjuster  28  includes a toothed rack (not shown) that is slidably movable within the adjusting post  18 , and that is securely positioned by meshing of the teeth with a splined shaft of the vertical-adjust dial  34 . When the adjusting post  18  is received between the parallel arms  16 , the toothed rack is vertically movable perpendicular to the parallel arms  16 . The first blade  26  is fixedly mounted on an end of the toothed rack protruding from the adjusting post  18 , for example by a screw, by adhesive, or by integral forming of the first blade  26  on the toothed rack. Accordingly, the first blade  26  is vertically adjusted perpendicular to the parallel arms  16  by operation of the dial  34 . 
         [0023]    Referring now to  FIGS. 1 and 3 , the movable post assembly  19  carries a second blade  38  for scoring the sheetrock at a second desired position on a face of the sheetrock opposite the first desired position. The second blade  38  is rotatably mounted to the movable post assembly  19 . The movable post assembly  19  also has two horizontal grooves  40  for engaging with the corresponding horizontal ridges  22  of the parallel arms  16 . The movable post assembly  19  includes a horizontal and vertical positioner  42  for vertically and horizontally positioning the second blade  38  relative to the frame  12 . Like the adjusting post  18 , the movable post assembly  19  is marked with measurements indicating a vertical position of the second blade  38  perpendicular to the parallel arms  16 . A horizontal distance between the adjusting post  18  and the movable post assembly  19  along the parallel arms  16 , as indicated by the measurements marked along the slot  24 , corresponds to a thickness of the sheetrock to be scored or cut using the device  10 . 
         [0024]    The movable post assembly  19  further includes a rectilinear frame  62  having two outer faces  48  in which are formed the horizontal grooves  40  for mating with the horizontal ridges  22 . The frame  62  also has inner faces  50  opposed to the outer faces  48 , inner faces  64  substantially perpendicular to the inner faces  50 , and outer faces  65  opposed to the inner faces  64 . A hole  54  extends from one of the horizontal grooves  40  to the corresponding inner face  50 , and a hole  55  extends from one of the outer faces  65  to the corresponding inner face  64 . Vertical faces  56  and  66  of the central block  46  abut and slide against the inner faces  50  and  64 . Again, the second blade  26  is mounted to the central block  46 . 
         [0025]    The horizontal and vertical positioner  42 , as shown in  FIGS. 1 and 3 , includes the dial  68  mounted on a threaded shaft  74  that extends through the slot  24  to cooperate with threads of the hole  54  in the frame  62  for drawing the frame  62  toward the parallel arm  16   a,  thereby clamping the frame  62  to prevent motion along the parallel arms  16 . The horizontal and vertical positioner  42  also includes a dial  76  having a threaded shaft  77  that cooperates with threads of the hole  55  in the frame  62  for clamping the central block  46  against motion perpendicular to the parallel arms  16 . 
         [0026]    Thus, the horizontal and vertical positioner  42  is operable to prevent motion of the movable post assembly  19  and of the second blade  26  relative to the frame  12 . In another version of the horizontal and vertical positioner  42 , a vertical groove is formed in one of the vertical faces  66  of the central block that is disposed closest to the parallel arm  16   a.  The vertical groove has a T-section and the horizontal and vertical positioner  42  includes a nut captured and slidably movable within the vertical T-groove. When the dial  68  is operated to tighten the horizontal and vertical positioner  42 , the central block  46  is drawn toward the parallel arm  16 a by action of the nut in the T-groove, thereby clamping the frame  62  and securely positioning the movable post assembly  19  and the second blade  26  relative to the frame  12 . When the dial  68  is operated to loosen the horizontal and vertical positioner  42 , the central block  46  is released to slide vertically within the frame  62 , and the frame  62  is released to slide horizontally along the ridges  22 , thereby permitting the second blade  26  to be positioned relative to the frame  12 . 
         [0027]    In an alternative embodiment shown in  FIGS. 2 and 4 , the movable post assembly  19  includes two slides  44  and a central block  46  to which the second blade  38  is mounted. Each of the slides  44  has an outer face  48  abutting one of the parallel arms  16 , on which the horizontal groove  40  is formed, and an inner face  50  abutting the central block  46 , on which a vertical ridge  52  is formed. A slotted through-hole  54 , as best shown in  FIG. 4 , is formed in each slide  44  extending from the horizontal groove  40  to the vertical ridge  52 . The central block  46  has two opposing faces  56  abutting the two slides  44 . In each opposing face  56  is formed a vertical groove  58  that slidably mates with the corresponding vertical ridge  52 . A vertical slot  60  extends through the central block  46  perpendicular to the opposing faces  56 , and is aligned with the holes  54  when the central block  46  is assembled to the slides  44 . 
         [0028]    The horizontal and vertical positioner  42 , as shown in  FIGS. 2 and 4 , includes a dial  68  mounted on a threaded shaft  70  that extends through the slots  24  of the parallel arms  16 , through the vertical slot  60  of the central block  46 , and through the slotted holes  54  of the slides  44  to cooperate with a clamping means  72  associated with the parallel arm  16   b.  In a simple version of the first embodiment, the clamping means  72  is a nut slidably abutting on a surface of the arm  16   b  opposed to the horizontal ridge  22  of the arm  16   b.    
         [0029]    When the dial  68  is operated to tighten the clamping means  72 , the two parallel arms  16  are drawn together to clamp therebetween the slides  44  and the central block  46 , thereby securing the movable post assembly  19  and the second blade  26  relative to the frame  12 . Loosening the horizontal and vertical positioner  42  enables the slides  44  to be moved horizontally along the ridges  22  and enables the central block  46  to be moved vertically along the grooves  52 , thereby permitting the second blade  26  to be positioned relative to the frame  12 . 
         [0030]    Optionally, each of the parallel arms  16  can have a removable pin  80  set into a hole formed on the horizontal ridge near the free end of the arm  16 , so that post assembly  19  cannot slide out of frame  12  even if the horizontal and vertical positioner  42  accidentally is removed from the slot  24 . 
         [0031]    Many materials, including wood, thermoplastic, and metal, are suitable for making the frame  12 , the adjusting post  18 , and the various parts of the movable post assembly  19 . The adjuster  28  and the positioner  42  should be made from a sturdy material durable for frequent operation. The first and second blades  26 ,  38  should be made from a tough and hard material suitable for scoring sheetrock and suitable for holding an edge. Hard woods such as oak, hard thermoplastics such as polycarbonate or polyvinyl chloride, and many various metals are suitable for making the first and second blades  26 ,  38 . 
         [0032]      FIG. 4  shows an ergonomic handle  82 . The handle  82  can be mounted to the frame  12  by various means. In one embodiment, the handle  82  comprises a base portion  84  and a grip portion  86 , and is mounted to the frame  12  by screws  88  inserted through holes formed in the base portion  84 . Although the handle can be made of various materials, it is preferred that the base portion  84  be formed of a sturdy material such as metal or hard plastic, and that the grip portion  86  comprise a cushioning material such as rubber or thermoplastic foam. 
         [0033]    In operation, an edge of a sheetrock panel is placed in between the adjustable post  18  and movable post assembly  19  such that the panel edge  104  abuts the underside of the parallel arms  16   a,    16   b.  The adjuster  28  and the positioner  42  are operated to position the first and second blades  26 ,  38  at a desired cut depth  100  (indicated on the vertical measurement marks of the posts  18  and  19 ) and at a thickness of the panel  102  (indicated on the horizontal measurement marks of the parallel arms  16 ). The device  10  is then dragged along the edge in a smooth motion. The first and second blades  26 ,  38  drag along opposing faces of the panel, thereby scoring or cutting the panel at the desired cut depth. 
         [0034]    While the invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various obvious changes may be made, and equivalents may be substituted for elements thereof, without departing from the essential scope of the present invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed.