Abstract:
A fixturing device for holding a workpiece with a longitudinal axis is disclosed. The fixturing device includes a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block that is similar to the first v-block is also provided. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. A cross-member adjustably attaches the first v-block to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention relates to an apparatus for fixturing workpieces that are to be drilled, more specifically, to a drilling fixture that can be used for the precision drilling of holes in workpieces of different shapes and sizes.  
         [0003]     2. Description of the Related Art  
         [0004]     It is prior-art practice, for example, in the case of drilling holes in workpieces to use a hand drill with a center punch for marking the location to be drilled. This practice has the disadvantage that the drill bit can walk on the workpiece thereby causing a marring of the workpiece or causing the hole to be drilled at an improper location. Also, there is the disadvantage that since the drill bit is not oriented or guided with respect to the workpiece the drilled hole will not be drilled at the proper angle with respect to the axis, plane, surface, or diameter of the workpiece.  
         [0005]     In order to deal with these problems it is known from the prior art to use a drill press and to set the workpiece up with clamps and fixtures. This solution has the disadvantages that it is quite expensive to own a drill press and the space required for a drill press can be quite large. Furthermore, it is very time consuming to set up the workpiece for drilling holes, especially for a part, which requires multiple holes drilled at different center distances along its length. A further disadvantage is that there is a limitation to the length of a workpiece which may have a hole drilled along its longitudinal axis (the length of the workpiece is limited by the working height of the drill press).  
         [0006]     Accordingly, prior art drilling devices have the disadvantages that they do not provide a satisfactory solution for quickly setting up and accurately drilling a hole in the workpiece by securing the work piece for facilitating any hole placement (i.e., along the longitudinal axis, plane, or diameter of the workpiece, perpendicular to the longitudinal axis of the workpiece, or making multiple holes at any given center distance).  
       SUMMARY OF THE INVENTION  
       [0007]     It is accordingly an object of the invention to provide a drilling fixture which overcomes the above-mentioned disadvantages of the heretofore-known devices of this general type and which provides a drilling fixture that is accurate, easily manufactured, easy to maintain, quick and simply to use, has a great deal of versatility, and is reliable.  
         [0008]     The present invention has the advantages that it is not restricted to just two holes at any center distance, it can be a multitude of hole locations and center distances. It securely clamps or locates over a specific hole location and because of its construction, it will not allow a drill bit to slip, mar, misalign or scratch plated or painted surfaces. This is especially important on painted or other finished workpieces. The present invention has the capability of drilling multiple work pieces exactly alike.  
         [0009]     The simplicity of the present invention allows anyone with various skill levels to successfully use the drilling fixture. It is very lightweight and extremely portable.  
         [0010]     The present invention is applicable in the following fields of use: pipe fitting and plumbing instances, fabricating shops (steel, wood, etc.); welding shops (positioning weldments etc.); in medical fields (accuracy in bone repair and reinforcing plates to be located, drilled and screwed); and irrigation (adding sprinklers to existing lines by accurately drilling and tapping for a specific nipple size).  
         [0011]     The present invention is convenient to use for the following applications: for locating holes to be drilled in round bars and dowel tubes; accurate drilling of bar stock (round, square, hex or rectangular) perpendicularly or at other angles; drilling, with a high level of accuracy, a hole in the end of any length work piece (dowels etc.); drilling out a broken screw in an existing hole; and accurately drilling a hole through the corner of a square bar tube or angle iron.  
         [0012]     The present invention also achieves subsequent hole locations at perpendicular or angular locations intersecting with or being offset to previously drilled holes (such as is used in building of furniture or table legs).  
         [0013]     The present invention will adapt to any shape work piece (i.e. square, rectangular, round, hex or elliptical). It also has a very unique feature that allows a user to drill any size through hole or blind hole in a circular helical pattern of infinite center distances and angular positions which could conceivably produce a work piece that would have a spiraling pattern for whatever length desired (such as a barber pole pattern).  
         [0014]     With the foregoing and other objects in view there is provided, in accordance with the invention a fixturing device for holding a workpiece having a longitudinal axis. The device has a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block has holding surfaces that intersect each other at an intersection and form a v-shape. The second v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces of the second v-block. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. A cross-member adjustably attaches the first v-block to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block.  
         [0015]     In accordance with another feature of the invention, a locating arm is mounted to the first v-block for positioning the workpiece in the direction of its longitudinal axis. A channel is formed in the first v-block for accommodating the locating arm.  
         [0016]     In accordance with a further feature of the invention, the first and second v-blocks each have a respective groove formed therein for accommodating the cross-member. The grooves are substantially parallel to the longitudinal axis of the workpiece.  
         [0017]     In accordance with an added feature of the invention, the locating arm is L-shaped, has a hole formed therein for receiving one of the at least one drill bushings. A slot is formed in the locating arm for adjusting a position of the locating arm in the channel.  
         [0018]     In accordance with an additional feature of the invention a 90° radial locating arm has a hole formed therein. The 90° radial locating arm is removably and adjustably mounted to one of the cross member, the first v-block, and the second v-block. One of the at least one drill bushing is removably disposed in the hole of the 90° radial locating arm. A locating pin is insertable into the one of the at least one drill bushings and into a hole formed in the workpiece for radially locating the workpiece.  
         [0019]     In accordance with yet another feature of the invention, a tube is removably disposed in the hole of the locating arm and a stop bar is adjustably mounted to the tube for positioning the workpiece in a direction along the longitudinal axis of the workpiece.  
         [0020]     In accordance with yet a further feature of the invention, a 45° radial locating arm has a hole formed therein, the 45° radial locating arm is removably and adjustably mounted to one of the cross member, the first v-block, and the second v-block. One of the at least one drill bushings is removably disposed in the hole of the 45° radial locating arm. The locating pin is insertable into the one of the at least one drill bushings and into a hole in the workpiece for radially locating the workpiece.  
         [0021]     In accordance with yet an added feature of the invention, the tube includes graduations for positioning the stop bar and the cross member includes graduations for positioning the second v-block with respect to the first v-block.  
         [0022]     In accordance with yet an additional feature of the invention, a further drill bushing has a chamfer. A chamfer is formed in the hole of the L-shaped bracket aligning with the chamfer of the drill bushing when the further drill bushing is inserted into the L-shaped bracket. The chamfers co-axially align the hole of the L-shaped bracket with the workpiece.  
         [0023]     In accordance with still another feature of the invention, one of the at least one drill bushings is insertable into the hole in the L-shaped bracket for drilling a hole along the longitudinal axis of the workpiece.  
         [0024]     With the objects of the invention in view, there is also provided in accordance with the invention a fixturing device for holding a workpiece with a longitudinal axis. The device includes a v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the v-block. At least one drill bushing is removably disposed in the hole of the v-block.  
         [0025]     In accordance with still a further feature of the invention, a channel is formed in the v-block. A locating arm for positioning the workpiece along a direction of its longitudinal axis is mounted in the channel. The locating arm is L-shaped, has a hole formed therein, and a slot formed therein for adjusting a position of the locating arm in the channel.  
         [0026]     In accordance with a further feature of the invention, a tube is removably disposed in the hole of the locating arm and a stop bar is adjustably mounted to the tube for positioning the workpiece in a direction along the longitudinal axis of the workpiece.  
         [0027]     In accordance with an added feature of the invention, a 90° radial locating arm has a hole formed therein, the 90° radial locating arm is removably and adjustably mounted to the v-block. One of the at least one drill bushings is removably disposed in the hole of the 90° radial locating arm. A locating pin is insertable into one of the at least one drill bushings and into a hole in the workpiece for radially locating the workpiece.  
         [0028]     In accordance with an additional feature of the invention a 45° radial locating arm has a hole formed therein, the 45° radial locating arm is removably and adjustable mounted the v-block. One of the at least one drill bushings is removably disposed in the hole of the 45° radial locating arm. The locating pin is insertable into the at least one drill bushing and into a hole in the workpiece for radially locating the workpiece.  
         [0029]     With the objects of the invention in view, there is also provided a fixturing device for holding a workpiece having a longitudinal axis. The device has a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block has holding surfaces that intersect each other at an intersection and form a v-shape. The second v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces of the second v-block. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block.  
         [0030]     Other features which are considered as characteristic for the invention are set forth in the appended claims.  
         [0031]     Although the invention is illustrated and described herein as embodied as a fixturing device for drilling workpieces, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.  
         [0032]     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0033]      FIG. 1  is a diagrammatic perspective view of the drilling fixture according to the invention as seen from the workpiece holding side with a round workpiece mounted in the drilling fixture;  
         [0034]      FIG. 2  is a perspective view of the drilling fixture according to  FIG. 1  as seen from the workpiece holding side with a square workpiece mounted in the drilling fixture;  
         [0035]      FIG. 3  is an exploded view of the drilling fixture according to  FIG. 1  as seen from the workpiece holding side;  
         [0036]      FIG. 4  is a perspective view of the drilling fixture according to  FIG. 1  as seen from the workpiece holding side with a square workpiece mounted in the drilling fixture with the v-blocks separated from the connecting bar; and  
         [0037]      FIG. 5  is a partial perspective view of the drilling fixture according to  FIG. 1  as seen from opposite the workpiece holding side showing a locating mechanism for axial drilling of the workpiece;  
         [0038]      FIG. 6  is a partial perspective view of the drilling fixture according to  FIG. 1  showing a conical locator for locating an L-shaped locating bar; and  
         [0039]      FIG. 7  is a perspective view of the drilling fixture according to  FIG. 1  as seen from the workpiece holding side, where the fixture is set up to drill a hole that is co-axial to the longitudinal axis of the workpiece. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0040]     Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 1  thereof, there is seen a drilling fixture according to the invention. The drilling fixture allows for the accurate drilling of differently aligned holes in a workpiece.  
         [0041]     The drilling fixture includes a first v-block  11  and a second v-block  21 , which are attached to each other by a mounting cross-member bar  6 . The v-blocks  11  and  21  each have respective holding or locating surfaces  114  and  124  that support the workpiece when it is being drilled. It is noted that while the angle between the holding surfaces  114  and  124  of the v-blocks  11  and  21  is illustrated as being 90° it is not necessary that the angle between the holding surfaces  114  and  124  of the v-blocks  11  and  21  be 90°. The angle can be adjusted for the types of workpieces to be handled by the drilling fixture. The holding surfaces  114  and  124  intersect each other and form a v-shape. Transverse axes of the v-blocks  11  and  21  bisect the v-shape of the v-block and are perpendicular to the longitudinal axis of the workpiece  1 , while the longitudinal axis of the v-blocks is parallel to the longitudinal axis of the workpiece  1  being held.  
         [0042]     The first v-block  11  includes a hole  13  having an axis that is parallel to the transverse axis of the first v-block  11 . The hole  13  ( FIG. 3 ) accommodates drill bushings  14 , which can be used to drill different sized holes (based on the size of the guide hole of the drill bushing), which are perpendicular to the longitudinal axis of the workpiece  1 . The drill bushings  14  have a flat ground on the outer diameter, which prevents the drill bushing  14  from rotating by way of a set screw  15  provided in the v-block  11 .  
         [0043]     The first v-block  11  includes a first groove  12 , which runs parallel to the longitudinal axis of the first v-block  11 . The groove  12  is used for mounting a cross-member bar  6 . The groove  12  includes a threaded hole  19  for attaching the first v-block  11  to the cross-member bar  6 . The first v-block  11  includes a second groove  31 , which runs parallel to the transverse axis of the first v-block  11 . The second groove  31  accommodates an L-shaped locating bar  7 , which will be discussed in further detail below. The L-shaped locating bar  7  is attached to the first v-block by a screw held in threaded hole  79 .  
         [0044]     The first v-block  11  includes an L-shaped clamping arm  16  that is attached thereto and is disposed parallel to the transverse axis of the first v-block  11 . The clamping arm  16  includes a threaded hole  17 , which, accommodates a screw holder  18  for holding/clamping the workpiece  1  in position for drilling of the workpiece  1 . It is possible to hold the clamping arm  16  and thus the drilling fixture in a vise when drilling holes in the workpiece  1 .  
         [0045]     The second v-block  21  includes a hole  23  having an axis that is parallel to the transverse axis of the second v-block  21  and also the first v-block  11 . The hole  23  ( FIG. 3 ) accommodates drill bushings  14 , which can be used to drill different sized holes (based on the size of the guide hole of the bushing), which are perpendicular to the longitudinal axis of the workpiece.  
         [0046]     The second v-block  21  includes a groove  22 , which runs parallel to the longitudinal axis of the second v-block  21  and also the longitudinal axis of the first v-block  11 . The groove  22  ( FIG. 3 ) is used for mounting the cross-member bar  6 . The groove  22  includes a threaded hole  29  for attaching the second v-block  21  to the cross-member bar  6 .  
         [0047]     The second v-block  21  includes a L-shaped clamping arm  26  that is disposed parallel to the transverse axis of the second v-block  21 . The clamping arm  26  includes a threaded hole  27 , which accommodates a screw holder  28  for holding/clamping the workpiece  1  in position for drilling of the workpiece  1 . It is possible to hold the clamping arm  26  in a vise when drilling holes in the workpiece  1 .  
         [0048]     A 90° radial locating arm  8  is provided for allowing alignment of the workpiece for the drilling of holes that are located 90° in relation to an existing hole. Alternatively, the 90° radial locating arm  8  can be used to drill a hole at 90° to an existing hole. The 90° radial locating arm  8  includes a hole  81  for accepting the drill bushings  14 . A set screw  15  holds the selected drill bushing  14  in place. Locating pins  3  sized for matching the sizes of the guidance hole of the drill bushings  14  are used to locate the workpiece  1  for drilling a new hole at 90° (based on the presence of a previously drilled hole in the workpiece). The 90° radial locating arm  8  includes a slot  82  which fastens the 90° radial locating arm  8  to the cross-member bar  6  or to either one of the first and second v-blocks  11 ,  21 . The slot  82  allows the 90° radial locating arm  8  to be positioned for different diameter/thickness workpieces  1 .  
         [0049]     A 45° radial locating arm  9  is provided for allowing alignment of the workpiece  1  for the drilling of holes that are located at 45° or 135° in relation to an existing hole. Alternatively, the 45° radial locating arm  9  can be used to drill a hole at 45° to an existing hole, i.e. in the corner of a square workpiece. The 45° radial locating arm  9  includes a hole  91  for accepting the drill bushings  14 , which are held in place by a set screw  15 . Locating pins  3  are used to locate the workpiece  1  in the same manner as is done with the 90° radial locating arm  8 . The 45° radial locating arm  9  includes a slot  92 , which fastens the 45° radial locating arm  9  to the cross-member bar  6  or to either one of the v-blocks  11  and  21 . The slot  92  allows the 45° radial locating arm  9  to be positioned for different diameter/thickness workpieces  1 . Furthermore, it is possible for the 45° locating arm to be mounted in the second groove  31  of the first v-block  11 , in the same manner as the L-shaped locating bar  7 . Using the 45° radial locating arm in the second groove  31  allows the drilling fixture to be able to drill holes for joinery (picture frames). Although the radial locating arms have been disclosed as being 45° and 90°, the radial locating arms can be made at any angle desired depending on the necessary application.  
         [0050]     The cross-member bar  6  includes a hole  61  for mounting the first v-block  11  to the cross-member bar  6 . The cross-member bar  6  also includes a slot  62  for mounting the second v-block  21 . The cross-member bar  6  also has graduations  63  for setting an exact distance of the second v-block  21  in relation to the first v-block  11 . As noted above, the slot  62  is also used for mounting the radial locating arms  8  and  9 .  
         [0051]     The L-shaped locating bar  7  mounted in the groove  31  by a screw  78  is rotatable 180° in the groove  31  ( FIGS. 1 and 7 ). The L-shaped locating bar  7  includes a hole  71  which can accommodate the drill bushings  14  for drilling an axial hole in the end of a workpiece  1  ( FIG. 7 ). The hole  71  in the L-shaped locating bar  7  can also accommodate a tube or rod  5  that is used together with a stop bar  4  for accurately positioning and locating the workpiece  1  in the longitudinal direction ( FIG. 4 ). A set screw  15  firmly holds the drill bushings  14  or the tube  5  in place. The L-shaped locating bar  7  has a slot  72  for movably mounting the bar  7  in the groove  31 . The L-shaped locating bar  7  has an end surface  75 , which acts a stop for squarely positioning a square or rectangular workpiece  1  in the v-blocks  11  and  21  ( FIG. 2 ). The L-shaped locating bar  7  also includes graduations  73  for the positioning of the bar  7  with respect to the first v-block  11 . As shown in  FIG. 6 , a conical locator drill bushing  76  is inserted into the hole  71  of the locating bar  7 . The conical locator bushing has a 45° chamfer at an end face thereof for seating the workpiece  1 , which centers the hole  71  of the locating bar  7  with the longitudinal axis of the workpiece. The locating bar  7  includes a 45° chamfer at an end face thereof that aligns with the chamfer of the locator drill bushing  76 . This allows the centering of a workpiece  1  which has a diameter greater than that of the conical locator drill bushing  76 . The use of the conical locating drill bushing  76  with the bar  7 , provides for drilling a hole that is co-axial with the longitudinal axis of the workpiece  1 .  
         [0052]     As is shown in  FIG. 3 , the rod  5  includes graduations  53  for positioning the stop bar  4 , which is mounted on the rod  5  by a hole  41 . The rod  5  has a shoulder  54  for locating the rod  5  in the hole  71  of the L-shaped locating bar  7 . The rod  5  has a flat surface  52 , for holding a set screw  15  mounted in the stop bar  4 . The set screw allows the stop bar  4  to be positioned using the graduations  53  of the rod  5 . The stop bar  4  has a slot  42 , which allows access to the screw  78  which retains the L-shaped locating bar  7  so that the L-shaped locating bar  7  may be adjusted when the stop bar  4  is in place.  
         [0053]     The operation of the device will be described with respect to the drawings and the above-provided description.  
         [0054]      FIG. 1  shows the device set up for drilling radial holes on the outer perimeter of the workpiece  1 . The v-blocks  11  and  21  are set in position on the cross-member bar  6 . The stop bar  4  is positioned on the rod  5  to set the longitudinal position of the workpiece  1 . Next, the workpiece  1  is clamped to the first and second v-blocks  11  and  21  by the clamping arms  16  and  26  and the screw holders  18  and  28 . Once the workpiece  1  is in position, accurately positioned radial holes may be drilled in the workpiece  1  by guiding a drill bit through the drill bushings  14 , which are mounted in the v-blocks  11  and  21 . In order to drill a hole which is indexed at 45°, 90° , or 135° the appropriate radial locating arm is attached to the cross-member bar  6  and the workpiece  1  is unclamped and rotated until the pin  3  is inserted through the radial locating arm into a previously drilled hole. The workpiece is then re-clamped, the pin is removed and additional holes can be drilled via the drill bushings  14  disposed in the v-blocks  11  and  21 .  
         [0055]      FIG. 2  shows that a rectangular or square workpiece  1  can be placed squarely in the v-blocks  11  and  21  by abutting the end surface  75  of the L-shaped locating bar  7  against the rectangular workpiece  1 . The screw holders  18  and  28  are tightened against the workpiece  1  and the rectangular workpiece is squarely and securely positioned with respect to the v-blocks  21  and  22 .  
         [0056]      FIG. 4  shows that holes can be drilled in a longer workpiece  1  by separating the second v-block  21  from the cross-member bar  6 . The second v-block  21  is then free to be positioned at any location on the workpiece  1 . When the drilling fixture is used in this manner the fixture is placed on a flat worktable by resting on the L-shaped clamping arms  16  and  26  of the respective v-blocks  11  and  21 .  
         [0057]      FIG. 6  shows the use of the conical locator  76  for drilling a hole that is co-axial with the longitudinal axis of the workpiece  1 . The conical locating drill bushing  76  is placed in the hole  71  of the L-shaped locating bar  7 . The end of the workpiece is pushed against the conical locating drill bushing  76 , which in turn positions the locating bar  7  in the groove  31  so that the conical locator  76  seats itself on the workpiece  1 . The conical locating drill bushing  76  is removed and the appropriate size drill bushing  14  is inserted into the hole  71  of the L-shaped locating bar  7  and a hole is drilled in the end face of the workpiece  1 .