Abstract:
A method and apparatus for guiding a cutting tool. The apparatus comprises at least one elongate member having a first track extending longitudinally therealong and a first clamping member located at a first end of a first elongate member and extending perpendicularly thereto. The apparatus further includes a second clamping member slidably locatable along the first track. The second clamping member is adjustably securable within the first track so as to clamp a work piece between the first and second clamping member. The method comprises longitudinally connecting the first and second elongate members with a connection member, applying the first and second elongate members to a surface of the material and clamping the elongate member to the material at a position corresponding to a line to be cut in the material between the first clamping member and the second clamping member.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of priority from U.S. Provisional Patent Application No. 61/340,706 filed Mar. 22, 2010 entitled Exacta-guide. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of Invention The present invention relates to tools in general and in particular to a method and apparatus for guiding one of a plurality of tools along a work surface. 
         [0003]    2. Description of Related Art 
         [0004]    In the fields of woodworking and construction, hand and portable power tools are frequently employed to cut, rout or otherwise machine a portion of the wood. Such tools are frequently required to perform such task in a straight line across or along the work piece so as to ensure a straight edge or consistent finish. 
         [0005]    With the use of hand or portable power tools, a guide is frequently employed to provide a straight line across the work piece for the tool to follow so as to ensure a straight cut. Such guides have previously been insufficient for use in a wide variety of cutting tools and a wide variety of cutting situations. 
         [0006]    Some guides have been adapted to cut across wide work pieces and have therefore included a long guide member which may be connected at various locations along the guide member. Such guides are cumbersome for use with smaller work pieces due to the excess length extending therefrom. Many of these types of guides include threaded fastening means which clamp the work piece between a threaded member and a base surface due to the need to apply a solid connection to the work piece. Such fastening means are known to be time consuming to apply. One example of such a prior guide may be found in U.S. Pat. No. 7,063,000 to Molburg. 
         [0007]    Other guides are designed to have stricter limits placed upon the lengths of the cut that they may guide which has limited their use on wider work pieces. Such guides have included a captured clamping member having a limited motion of travel to provide the above limit on the cut length. Such a limit to the work piece size however either requires that the device be limited to small cut lengths so as to be of a manageable size for small jobs or to have a length so long that they would become awkward for when used with smaller work pieces than for which they were designed. Thus many such guides are a compromise of the usefulness for their intended size range verses the range of cuts for which they may be used. Many of these type of devices also have clamping mechanisms are to be adjusted to a desired position on either side of the work piece and then tightened against the guide member which do not provide a satisfactory clamping force. An example of such guides may be found at U.S. Pat. No. 3,913,440 to Baker. 
       SUMMARY OF THE INVENTION 
       [0008]    According to a first embodiment of the present invention there is disclosed an apparatus for guiding a cutting tool. The apparatus comprises at least one elongate member having a first track extending longitudinally therealong a first clamping member located at a first end of a first elongate member and extending perpendicularly thereto. The first clamping member is operable to have an indicator corresponding to a cutting line of the cutting tool cut therein by the cutting tool. The apparatus further includes a second clamping member slidably locatable along the first track. The second clamping member is adjustably securable within the first track so as to clamp a work piece between the first and second clamping member. 
         [0009]    The at least one elongate member may comprise a plurality of elongate members longitudinally connected to each other. The plurality of elongate members may be connectable to each other with a connector member. The plurality of elongate members may further include a second track extending longitudinally therealong. The second track may comprise a second pair of interior opposed grooves located within the elongate member. The connector member may comprise a plate securable within the second track. 
         [0010]    The first track may comprise a first pair of interior opposed grooves located within the elongate member. The second clamping member may include a slide portion slidably received between the first pair of opposed grooves. The slide portion may comprise a plate connectable to a body portion of the second clamping member with a fastener wherein the body portion and the plate may grip a flange of the elongate member therebetween by tightening the fastener. The body portion may be formed of a material selected from the group consisting of rubber, plastic, wood or silicon. The body portion may include an inclined clamping surface adapted to wedge the work piece between the first and second clamping bodies as the apparatus is pressed downwardly on the work piece. 
         [0011]    The first clamping member may comprise a bar perpendicularly secured to the first elongate member. The first clamping member may be formed of a material selected from the group consisting of wood or plastic. The apparatus may further include a pair of parallel spaced apart of longitudinal alignment passages sized to receive a pair of alignment rods therein for aligning the plurality of elongate members. 
         [0012]    The alignment passages may be located between the first and second tracks. The apparatus may further comprise a guide arm rotatably connected to the first end of the first elongate member. 
         [0013]    According to a further embodiment of the present invention there is disclosed a method for sawing a material. The method comprises providing a first elongate member extending between first and second ends, inserting a connection member within the second end of the first elongate member and receiving the connection member within a first end of a second elongate member to form a continuous guide edge with the first and second elongate members. The method further comprises applying the first and second elongate members to a surface of the material and clamping the elongate member to the material at a position corresponding to a line to be cut in the material between a first clamping member located at a first end of the first member and a second clamping member slidably and selectably fixably locatable within a first track of the first and second elongate members. 
         [0014]    The method may comprise locating the first clamping member adjacent to a first edge of the work piece, locating a inclined clamping surface of the second clamping member adjacent to a second edge of the work piece and pressing the second clamping member onto the work piece so as to wedge the work piece between the first and second clamping bodies. 
         [0015]    Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view, 
           [0017]      FIG. 1  is a perspective view of a guide apparatus according to a first embodiment of the present invention having an angular guide member extended therefrom. 
           [0018]      FIG. 2  is a perspective view of the guide apparatus of  FIG. 1  with a guide extension applied thereto. 
           [0019]      FIG. 3  is a cross sectional view of the guide apparatus of  FIG. 1  as taken along the line  3 - 3  from  FIG. 2 . 
           [0020]      FIG. 4  is a cross sectional view of the guide apparatus of  FIG. 1  as taken along the line  4 - 4  from  FIG. 2 . 
           [0021]      FIG. 5  is an exploded perspective view of the clamping member of the guide apparatus of  FIG. 1 . 
           [0022]      FIG. 6  is a cross sectional view of the clamping member of  FIG. 5  as taken along the line  5 - 5 . 
           [0023]      FIG. 7  is a side view of the apparatus of  FIG. 1  being applied to a work piece in a first position. 
           [0024]      FIG. 8  is a side view of the apparatus of  FIG. 1  being applied to a work piece in a second position. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Referring to  FIGS. 1 and 2 , an apparatus for guiding the path of a cutting tool according to a first embodiment of the invention is shown generally at  10 . The apparatus  10  comprises a first elongate member  12  extending between first and second ends,  14  and  16 , respectively, and first and second clamping members,  80  and  100 , respectively, for securing the elongate member to a work piece as will be more fully described below. The apparatus also includes an angular guide member or arm  50  pivotally attached to the first end  14  of the first elongate member  12 . The apparatus may also have additional elongate members  40  longitudinally secured to the second end  16  of the elongate member  12  as illustrated in  FIG. 2  so as to extend the length of the apparatus for use in cutting wider work pieces. Although only a single second elongate member  40  is illustrated connected to the first elongate member  12  in  FIG. 2 , it will be appreciated that more than one additional elongate member may be secured thereto as needed. In such applications, a connector member  70  as illustrated in  FIG. 1  may be utilized to connect the elongate members together. The first elongate member  12  may have a length selected to permit use in cutting a range of work pieces up to a conventional rage of dimension lumber, such as by selecting first elongate member  12  having length of between 12 and 20 inches (305 to 508 mm) by way of non limiting example. Similarly, additional elongate members  40  may thereafter be provided to permit the apparatus  10  to guide tools across work pieces of increased size. By way of non-limiting example, such additional elongate members  40  may have lengths of 33 inches (838 mm) although it will be appreciated that other lengths will be useful as well. 
         [0026]    The guide arm  50  comprises an elongate angular channel formed by horizontal and vertical planar sections,  52  and  54 , respectively extending between first and second ends,  56  and  58  respectively. The first end  56  is pivotally connected to the first end  14  of the elongate member  12  about a pin  60  and includes a plurality of angular indicators on a top surface thereof, generally indicated at  62 . Any one of the angular indicators may be selectably aligned with a reference indicator  64  located on the elongate member  12  to indicate the angle defined therebetween. When not in use to provide a non-parallel guide path from the elongate member, the guide arm may be located proximate thereto as illustrated in  FIG. 2 . The first end  56  of the guide arm  50  may also include an arcuate slot  66  extending there through having a radius about the pin  60  and a threaded post extending therethrough (not shown) and hand knob or wing nut  68  as are commonly known in the art located thereon so as to tighten the guide arm  50  against the elongate member  12  so as to fix the angular orientation thereof. 
         [0027]    Turning now to  FIGS. 3 and 4 , cross sectional views of the elongate members  12  and  40  are illustrated along the lines  3 - 3  and  4 - 4  of  FIG. 2 , respectively. The elongate member  12  comprises an elongate body having first and second side edges,  18  and  20 , respectively, and top and bottom sides,  22  and  24 , respectively. The bottom side  24  includes an interior cavity  26  therein having a first and second grooves or channels,  28  and  30 , respectively, for receiving the second clamping member and a connector member therein as well as a pair of passages  32  for receiving a pair of longitudinal alignment rods therein. The first set of opposed grooves  28  form a first track therebetween. As illustrated in  FIG. 3 , the first grooves  28  may receive the connector member  70  therein. The second set of opposed grooves  30  form a second track therebetween and are operable to receive a portion of the second clamping member therein as will be further described below. The passages  32  are sized to receive elongate alignment rods  80  or pins therein as illustrated in  FIGS. 1 and 3 . The alignment rods  80  may be selected to have a size corresponding to the passages  32  for a close fit therein and to have any length sufficient to assist in the alignment of the first and second elongate members. The passages  32  are defined by a pair of arcuately curved walls  34  extending from the first and second sides  18  and  20  of the elongate member and having a gap  36  between the distal ends thereof. As illustrated in  FIG. 4 , the first track may be located proximate to the bottom side  24  of the elongate member  12  wherein the second track is located proximate to the top side  22  of the elongate member with the passages  32  therebetween. In such an arrangement, the first grooves  28  forming the first track are defined between the bottommost curved walls  34  of the passages  32  and a bottom flange  38  of the elongate member. Similarly, the second grooves  30  forming the second track are defined between the topmost curved walls  34  and the top side  22  of the elongate member  12 . 
         [0028]    It will be appreciated that the first and second elongate members  12  and  40  have similar cross sectional profiles so as to facilitate the longitudinal movement of the second clamping member  100  therealong. However as illustrated in  FIG. 3 , it will be observed that the first elongate member  12  has a width  42  selected to be less than the width  44  of the additional elongate members  40  so that when the guide arm  50  is located proximate thereto, the guide arm  50  and first edge  18  of the second elongate member will provide a continuous guide surface. In particular, it will be observed that the width difference between the first and second elongate members  12  and  40  may be accomplished by reducing the thickness of the wall forming the first side edge  18  of the first elongate member  12  by an amount corresponding to the thickness of the vertical section  54  of the guide arm  50 . Accordingly the width of the first elongate member  12  and guide arm  50  combined, indicated at  46 , will be equal to the width  44  of the second elongate member  40  alone. As illustrated in  FIG. 3 , the first elongate member  12  may also include a chamfered corner  48  so as to facilitate the guide arm  50  being rotated into close proximity thereto. 
         [0029]    It will be appreciated that an elongate member according to the above description may be formed of any suitable material by any suitable methods. In particular, the elongate member may be formed of a metal, such as, by way of non-limiting example, aluminium, steel, stainless steel, copper or alloys thereof, plastics, ceramics or wood. The elongate member may also be formed of any suitable methods, such as, by way of non-limiting example machining, extrusion, bending, casting or roll forming. 
         [0030]    The second elongate member  40  may be connected to the first elongate member by inserting a connector member  70  into the second grooves  30  as illustrated in  FIGS. 1 and 3 . The connector member  70  comprises a plate sized to be received within the first grooves  30  having bores  72  therein sized to receive fasteners  74 , such as, by way of non-limiting example screws, bolts, pins or rivets therein. The first and second elongate members  12  and  40  also include corresponding bores  73  sized to pass the fasteners therethrough. Optionally the connector member  70  may be sized to be thicker than the first grooves  30  and include a shoulder  78   
         [0031]    The first clamping member  80  comprises a bar fixedly located proximate to the bottom of the first end  14  of the first elongate member having a clamping surface  82  disposed towards the second end  16  of the elongate member. The first clamping member  80  is oriented perpendicularly to the first elongate member  12  so as to provide a guide path that is normal to the edge of a work piece when the apparatus  10  is secured thereto. The first clamping member  80  may be secured to the first elongate member  12  by a bracket  84  and fasteners as illustrated in  FIGS. 1 and 2 . The first clamping member  80  may be formed of a material selected to permit machining by the cutting tool of the user. In particular, the first clamping member may be formed of any suitable machineable material, such as, by way of non-limiting example, wood or plastic. In operation a user may customize the first clamping member  80  of their apparatus to provide one or more measurement indicators corresponding to the cutting location of their tools. By way of non-limiting example, a user may make a first cut with a sabre saw slightly into the first clamping member  80  so as to provide a front notch  86 . The user may also make a first cut with a circular saw so as to remove a portion of the end of the first clamping member  80 , generally indicated at  90  or may make a first pass with a router to make a top notch  88 . The first front and top notches  86  and  88  and end of the first clamping member  80  may thereafter be utilized to guide the user as to the proper location of the apparatus to make their desired cut. It will be appreciated that the first clamping member  80  may also have a thickness sufficient to permit the router to be passed through without excessively weakening the first clamping member  80 . In particular, it has been found that a thickness of at least ½ inch (13 mm) has been suitable with a thickness of more than ¾ inch (19 mm) being particularly useful. 
         [0032]    Turning now to  FIGS. 5 and 6 , the second clamping member  100  comprises a clamping body  102  connectable to a plate  108  by a threaded fastener  107 , such as a carriage bolt. The clamping body  102  includes a bore  105  therethrough and a top shoulder  104  proximate to either side with a narrowed region  106  therebetween. The narrowed region  106  is sized to pass between the bottom flanges  38  of the first or second elongate members  12  or  40 . The clamping body  102  also includes an angularly oriented lead clamping surface  106  at a leading edge thereof. The clamping surface  109  may have an angle, generally indicated at  120  of between 0 and 60 degrees. The plate  108  is sized to be slidably received within the first grooves  28  of the first or second elongate ember  12  or  40  and includes square a bore  110  therethrough to receive a corresponding square portion  112  of the fastener  107 . The fastener  107  includes a threaded post  114  which is sized to be passed through the bore  105  of the clamping body  102  and threadably received within a threaded receptacle  118 , of a handle or knob  116 . In operation the plate  108  may be located within the first grooves  28  such that the bottom flange  38  of the first or second elongate member  12  or  40  is between the plate  108  and the shoulder  104  of the clamping body. Thereafter the fastener  112  may be tightened into the nut  118  so as to compressible grip the bottom flange  38  therebetween at a position as desired by the user. 
         [0033]    The clamping body  102  may be formed of a resilient material such as, by way of non-limiting example, natural or synthetic rubbers, plastics, silicon, wood, or composite materials. In particular the clamping body may be formed of a material having sufficient hardness to firmly grip the work piece while permitting a sufficient amount of flexibility to enable application thereto as described above. It has been found that rubbers having a Shore A hardness from about 80 to 100 has been useful. 
         [0034]    With reference to  FIGS. 7 and 8 , the apparatus  10  may be applied to a work piece  8  by placing the apparatus on top of the work piece and locating the first clamping member  100  proximate to a first edge  6  of the work piece. The second clamping member may then be slidably located along the first elongate member  12  to be proximate to the second edge  4  of the work piece. Optionally, a pencil  122  or other small object may be placed under the first elongate member  12  proximate to the second clamping body  100  so as to space the first elongate member  12  away from the work piece at that location as illustrated in  FIG. 7 . This additional spacing will permit the second clamping member  100  to be located closer to the first clamping member  80 . After the second clamping member  100  has been secured to this closer position, the pencil  122  may be removed and the elongate member pressed downwardly onto the work piece such that the clamping body  102  is biasedly deformed as the clamping surface  109  is slidably passed over the second edge  4  of the work piece  8 . It will be appreciated that the angular orientation of the clamping surface  109  assists with guiding the second clamping member  100  over the second edge  4  of the work piece while the compressible material of the second clamping body  102  serves to compressibly grip the work piece between the first and second clamping bodies thereafter providing a more secure clamping guide. 
         [0035]    While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.