Abstract:
The present invention discloses an improved miter gauge for retaining and adjustably positioning a workpiece. The miter gauge includes a fence frame pivotally mounted to a base member for adjusting the workpiece to be cut at a user selected angle. The fence frame includes a fence surface for positioning the workpiece. The fence surface is opposed by a quick-adjusting stopping unit mountable to the base member for clamping the workpiece therebetween.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a miter gauge for retaining and adjustably positioning a workpiece to be cut by a table saw or the like. 
   2. Background Art 
   Miter gauges are produced in a variety of different types and configurations. These gauges are commonly used for positioning a wooden workpiece to be cut at a user selected angle by a table saw. Miter gauges usually include a fence for abutting the workpiece. They commonly include a semicircular gauge for angular adjustment to a base member which slidingly cooperates within a slotted recess in the saw table top. 
   Conventional miter gauges generally do not include a stop for retaining the workpiece. Retaining a workpiece to be cut by a saw tends to be time consuming to set up and tedious for multiple cutting operations. The stop is frequently unnecessary if the user can easily hold the workpiece against the fence of the miter gauge during the sawing operation. However, not all workpiece styles are easy to hold against the miter gauge fence while cutting. A primary example, crown molding, is difficult to hold while cutting. Crown molding is ornamental by design and is typically used for decoration within corners, commonly requiring the molding to be cut at a miter angle. A crown molding section is primarily angular, but has perpendicular surfaces for abutting within the corner. These surfaces are small in comparison to the molding body and are difficult to hold against both the miter gauge fence and saw table at the correct angle. When the piece of crown molding is held abutting the fence, the user is forced to hold the molding along its ornamental side. 
   Provisions have been made in the past to eliminate the need for the user to hold the workpiece during cutting operations. U.S. Pat. No. 778,642, issued to R. Dunne, discloses a method for clamping a workpiece while applying miter cuts. However, this method requires loosening a nut, positioning a stop and retightening the nut in order to make a single cut. The time required to set-up the clamp may not justify the ease provided while cutting the workpiece. 
   Another invention for clamping the workpiece while cutting is disclosed in U.S. Pat. No. 4,165,668, issued to Vermont American Corporation. With this design, the user is required to adjust a vertical screw pad for the height of the workpiece, loosen a wing nut, position a moveable jaw, and retighten the wing nut in order to make a single cut. Although this design clamps the workpiece in both horizontal and vertical directions, this design is time consuming to set up also. 
   U.S. Pat. No. 4,875,399, issued to William D. Scott et al., discloses an invention for clamping a workpiece to be cut by a saw by use of registration blocks pivotally mounted to trap the lower edge of the workpiece. This design requires loosening of a nut, positioning a slide block, and retightening of the nut for a single cutting operation. This design prevents the user from holding the workpiece while cutting, but does not provide any means for quick adjustment. 
   Various techniques and designs have provided miter gauges and/or clamps for positioning a workpiece to be cut by a saw. Although these designs may eliminate the need for the user to hold the workpiece against the fence while making the cut, it may not outweigh the time and efforts required for adjusting the clamp. Further, the workpiece does not need to be clamped; rather, all that is required is that the workpiece be retained during the cutting operation. Accordingly, it is the goal of the present invention to provide a simple low cost miter gauge with a quick-adjusting stop for retaining the workpiece at a selected angle to be cut by a saw. 
   SUMMARY OF THE INVENTION 
   The stock stop miter gauge of the present invention is similar to conventional miter gauges, however, the present invention includes a quick-adjusting movable stopping unit for retaining the workpiece. This miter gauge includes a base member, a fence frame, an adjustment handle, and a stopping unit. The fence frame is pivotally rotatable with respect to the base member and the adjustment handle retains the fence frame at a user selected angle. The fence frame has a vertical fence for supporting the workpiece and the stopping unit retains the workpiece against the fence. The quick-adjusting stopping unit makes it much easier for the user to retain the workpiece while cutting and allows the user to perform similar cutting operations with little or no adjustment. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a prior art miter gauge with a typical prior art table saw; 
       FIG. 2  is a side view of the prior art miter gauge of  FIG. 1 ; 
       FIG. 3  is a top view of the prior art miter gauge of  FIG. 1 ; 
       FIG. 4  is a top view of the prior art miter gauge of  FIG. 1  with the workpiece positioned at a 45° angle; 
       FIG. 5  is a perspective view of a preferred embodiment miter gauge mounted on a table saw; 
       FIG. 6  is a side view of the miter gauge of  FIG. 5 ; 
       FIG. 7  is an enlarged section view of the stopping unit of the miter gauge of  FIG. 5 ; 
       FIG. 8  is an enlarged section view of the stopping unit taken along section line  8 — 8  in  FIG. 7 ; 
       FIG. 9  is an enlarged top plan view of the stopping unit with the workpiece position at an angle relative to the saw blade; 
       FIG. 10  is a perspective view of another embodiment miter gauge mounted upon a table saw; 
       FIG. 11  is a side view of the miter gauge of  FIG. 10 ; 
       FIG. 12  is an enlarged partial section view of the stopping unit of the miter gauge of  FIG. 10 ; 
       FIG. 13  is an enlarged partial top plan view of the stopping unit of the miter gauge of  FIG. 10  with the workpiece oriented at an angle to the saw blade. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1-4  illustrate a prior art miter gauge  20 .  FIG. 1  illustrates the miter gauge  20  used in combination with a prior art table saw  22 . The table saw  22  includes a table  28  with a saw blade  30  protruding through the table  28 . The miter gauge  20  includes a longitudinal base member  24 , made of a metal, typically aluminum. The base member  24  cooperates with a recess  26  formed within the table  28  parallel to the saw blade  30 . 
   Fence frame  32  is pivotally mounted to the base member by a pivot pin  34 . The pivot pin  34  is perpendicular to the table  28 . The fence frame  32  is a semicircular unit formed with an upright planar surface commonly referred to as a fence  36 . The fence  36  is typically formed of a high strength molded plastic. An arcuate slot  38  is formed through the fence frame  32  concentric to the pivot pin  34 . An adjustment handle  40  cooperates with the arcuate slot  38  and a has a threaded end engaged in a threaded hole  42  in the base member  24  as illustrated in FIG.  2 . 
   A user can adjust the fence frame  32  by loosening the adjustment handle  40  and rotating the fence frame  32  pivotally with respect to the base member  24 . Semicircular array of indicia  44  is formed about the fence frame  32 . A plurality of predetermined positions may be selected by aligning the desired angle indicated on the indicia  44  with an index pointer  46  formed to the base member  24 . Adjustment of the fence frame  32  determines the angle of the cut of workpiece  50  in respect to the saw blade  30 .  FIGS. 3 and 4  are examples illustrating different angular adjustments of the workpiece  50 . 
   The fence  36  has fence slots  52  allowing the user to mount a wooden fence extension  48  to the fence  36  with fasteners  54 . The extension  48  protects the workpiece  50  from any unwanted marks that may be caused by the fence  36  and extends the support surface. The extension  48  is typically supplied by the user, allowing the user to create an extension  48  that is an appropriate size for the application. The extension  48  can be cheaply and easily replaced if damaged, or modified to suit the specific workpiece to be cut. The extension  48  and workpiece  50  are shown in phantom in  FIGS. 1 ,  5  and  10  to provide clarity of the additional elements in these figures. 
     FIGS. 5 and 6  illustrate a preferred embodiment of a miter gauge  56 . Elements common to the prior art design retain like reference numbers, while modified components are renumbered. The miter gauge  56  includes a stopping unit  58  for retaining the workpiece  50  against the opposed fence surface  60  of the extension  48 . The stopping unit  58  is slidable within slot  62  formed within base member  64 . 
     FIG. 7  illustrates an enlarged section view of the stopping unit  58 .  FIG. 8  illustrates an enlarged section view along section line  8 — 8  in FIG.  7 . The stopping unit  58  includes an upper portion  66  and lower portion  68 . The upper portion  66  extends vertically out of the base member  64  through the slot  62 . The slot  62  is stepped within the base member  64 , providing gibs  72  and  72 ′ on opposed sides of the upper portion  66  of the stopping unit  58 . The lower portion  68  of the stopping unit  58  is wider than the slot  62  and is retained within the base member  64  by the gibs  72  and  72 ′. The base member  64  includes an upper portion  70  and lower portion  71  assembled together to house the stopping unit  58 . 
   The upper surface of the lower portion  71  oriented within slot  62  includes a plurality of first ramped teeth  74 . The lower portion  68  of the stopping unit  58  includes an opposing plurality of second ramped teeth  76 . A wave spring  78  is mounted to the lower portion  68  of the stopping unit  58 . The spring  78  is compressed between the gibs  72  and  72 ′ and the lower portion  68  of the stopping unit  58 , biasing the first and second sets of teeth  74  and  76  together as shown. 
   The design illustrated in this invention provides quick adjustment of the stopping unit  58  in a snap-and-slide motion. The first ramped teeth  74  are inclined in the direction of the fence  36 . This allows the user to retain the workpiece  50  by urging the upper portion  66  of the stopping unit in the direction of the workpiece  50 . Once the stopping unit  58  is indexed to a user selected position, the stopping unit  58  is retained in position by the engaged first and second ramped teeth  74  and  76 . 
   The present invention also permits the user to quickly adjust the stopping unit  58  away from the fence surface  60 . The user simply lifts the stopping unit  58  to bias the upper portion  66  in a direction away from the base member  64 . This compresses the wave spring  78 , allowing the first and second ramped teeth  74  and  76  to disengage. The user can then slide the stopping unit  58  in a direction away from fence surface  60 . 
     FIG. 9  illustrates an enlarged top view of the stopping unit  58  at another angular adjustment of the workpiece  50 . The upper portion  66  of the stopping unit  58  has a curved cylindrical surface  80  for contacting the workpiece  50 . The cylindrical surface  80  provides a line contact  82  with the workpiece  50  at any angular position. 
     FIGS. 10 and 11  illustrate another embodiment of a miter gauge  84 . Elements common to the prior art design retain like reference numbers, while modified components are renumbered. The miter gauge  84  includes a stopping unit  86  for retaining the workpiece  50  against the opposed fence surface  60  of the extension  48 . The stopping unit  86  includes a peg  88  cooperating with one of a plurality of sockets  90  formed within base member  92 . The sockets  90  are spaced incrementally allowing rough indexing of the stopping unit  86 . 
     FIG. 12  illustrates an enlarged partial cross section side view of the stopping unit  86 . The peg  88  has a body  94  and a smaller pivot diameter  96  forming a step  98 . The pivot diameter  96  is sized to allow the peg  88  to pivotally rotate within the sockets  90 . The step  98  rests atop the base member  92 . The body  94  of the peg  88  includes a threaded hole  100  for receiving a thumbscrew  102 . The thumbscrew  102  permits fine adjustment of the stopping unit  86  against the workpiece  50 . The thumbscrew  102  has a knurled surface  104  at one end for manual adjustment and a contact surface  106  at the opposed end for contacting the workpiece  50 . 
     FIG. 13  illustrates an enlarged top view of the stopping unit  86  with an angular adjustment of the workpiece  50 . The stopping unit  86 , being pivotally rotatable with respect to the base member  92 , allows the contact surface  106  to contact the workpiece  50  perpendicularly at any angle of adjustment of the workpiece  50 . 
   The present invention retains the workpiece  50 , permitting the user to securely hold the workpiece  50  during cutting. Accordingly, the present invention is a low cost solution to the miter gauge positioning problem while providing quick-adjustment in comparison to prior art devices. Further, it may be considered that the present invention may be used to clamp the workpiece  50 ; however stopping the workpiece  50  at a user-selected position is all that is necessary to perform a proper cutting operation. 
   While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.