Abstract:
A portable chamfer tool includes a housing configured to support a blade to cut a tenon into a workpiece as the housing is rotated about the workpiece. The portable chamfer tool also includes a passage through the housing configured to receive the workpiece and expose the workpiece to at least one blade to form the tenon and sighting holes disposed in the housing to expose a portion of the workpiece as it travels through the passage. The portable chamfer tool includes measuring marker disposed about the sighting holes to indicate a measure of a length of the portion of the workpiece exposed by the sighting holes. The portable chamfer tool provides a means to form a taper on a first end of a peg disposed in a tenon and mortise joint that is substantially matched to a preformed taper on a second end of the peg.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This is a continuation application of U.S. patent application Ser. No. 11/465,613 filed on Aug. 18, 2006, which claims the benefit of U.S. Provisional Patent Application No. 60/711,490 filed on Aug. 26, 2005, and entitled “Chamfer Tool.” The contents of the above applications are incorporated herein by reference in entirety. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0003]    The present invention relates generally to a system and method for chamfering a tenon or peg and, more particularly, to a system and method for accurately controlling a tenon or peg taper length using a portable chamfer tool. 
         [0004]    Traditional portable chamfer tools are useful tools in woodworking applications because they enable a user to create a tenon or tapered peg using traditional hand drills rather than a floor standing lathe or similar stationary tool. However, typical tools require the user to rely on estimated tenon or taper lengths and do not provide a means to accurately assess the length of the tenon or taper without ceasing the cutting process and removing the workpiece from the chamfer tool. As a result, these portable chamfer tools have limited applications 
         [0005]    For example, timber frame homes built using a traditional construction process are a popular home design option. Referring to  FIG. 1 , a traditional tenon-and-mortise joint  1  used in the construction of timber homes or buildings is shown. The mortise  3 , tenon  2 , and peg  4  are typically formed at a preformed and assembled during the job-site construction process. To construct the tenon-and-mortise joint  1 , the precut tenon  2  is aligned and positioned in the precut mortise  3  and the preformed pegs  4  are pounded through holes in the tenon-and-mortise joint  1 . Typically, the peg  4  is driven through the tenon-and-mortise joint  1  by using a mallet to strike a backside of the peg  4 . To aid in driving the peg  4  through the joint  1 , the peg  4  typically includes a tapered forward portion  5  and a full diameter backside portion  6 . That is, the forward portion  5  of the peg  4  includes a preformed taper configured to aid in driving the peg  4  into the joint  1 , while the backside portion  6  is not tapered to present a full striking surface for the builder to hit the mallet against. 
         [0006]    Referring now to  FIG. 2 , a rear elevational view of the joint  1  in assembled form is shown. Once the peg  4  has been driven through the joint  1 , the backside portion  6  of the peg  4  that was not driven into the joint  1  is sawed relatively flush with the joint  1 . As such, each joint  1  in a timber frame home or building generally has one tapered end  7  and one blunt end  8 , which is not particularly aesthetically pleasing to the eventual homeowner or building owner. 
         [0007]    Therefore, it would be desirable to have a system and method for accurately controlling the length of a tenon or tapered peg during the cutting process. Furthermore, it would be desirable to have a system and method to taper a blunt end of a peg driven through a mortise-and-tenon joint. 
       BRIEF SUMMARY OF THE INVENTION 
       [0008]    The present invention overcomes the aforementioned drawbacks by providing a system and method for accurately controlling a tenon or peg taper length using a portable chamfer tool. 
         [0009]    In accordance with one aspect of the invention, a portable chamfer tool is disclosed that includes a housing configured to support a blade to cut a tenon in a workpiece as the housing is rotated about the workpiece. The portable chamfer tool also includes a passage through the housing configured to receive the workpiece and expose the workpiece to at least one blade to form the tenon and at least one sighting hole disposed in the housing to expose a portion of the workpiece as it travels through the passage. The portable chamfer tool further includes a plurality of measuring markers disposed about the at least one sighting hole to indicate a measure of a length of the portion of the workpiece exposed by the at least one sighting hole. 
         [0010]    In accordance with another aspect of the invention, a method of constructing a tenon and mortise joint is disclosed that includes positioning a precut tenon inside a precut mortise and aligning at least one precut peg hole in the tenon with at least one precut peg hole in the mortise. The method further includes driving a first end of a peg having a preformed taper thereabout into the at least one precut peg hole in the tenon and the at least one precut peg hole in the mortise by striking a second end of the peg having a consistent diameter. Furthermore, the method includes forming a taper on the second end of the peg using a portable chamfer tool once the peg is positioned through the at least one precut peg hole in the tenon and the at least one precut peg hole in the mortise. 
         [0011]    In accordance with yet another aspect of the invention, a portable chamfer tool is disclosed that includes a first end configured to receive a workpiece for creating a tenon therein. The portable chamfer tool also includes a first portion configured to be rotated about the workpiece to cut the tenon from the workpiece and a second portion configured to receive the tenon as it passes from the first portion and provide a metered indication of a length of the tenon as it is formed by the first portion. 
         [0012]    Various other features and advantages of the present invention will be made apparent from the following detailed description and the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective exploded view of a mortise and tenon joint and factory tapered pegs; 
           [0014]      FIG. 2  is an assembled rear elevational view of the mortise and tenon joint of  FIG. 1 ; 
           [0015]      FIG. 3  is a plan view of a portable chamfer tool having a tenon/peg taper length sight and associated metering marks in accordance with the present invention; 
           [0016]      FIG. 4   a  is an additional plan view of the portable chamfer tool of  FIG. 3  having a tenon/peg taper length sight and associated metering marks; 
           [0017]      FIG. 4   b  is side elevational view of the portable chamfer tool of  FIGS. 3 and 4   a  having a tenon/peg taper length sight and associated metering marks; 
           [0018]      FIG. 4   c  is a perspective view of the portable chamfer tool of  FIGS. 3-4   b  having a tenon/peg taper length sight and associated metering marks; 
           [0019]      FIG. 4   d  is a front elevational view of the portable chamfer tool of  FIGS. 3-4   c  having a tenon/peg taper length sight and associated metering marks; 
           [0020]      FIG. 5  is a plan view of a portable chamfer tool having a tenon/peg taper length sight and associated metering marks in accordance with the present invention; 
           [0021]      FIG. 6   a  is a perspective view of an angled portable chamfer tool having a tenon/peg taper length sight and associated metering marks and showing a blade mounted in a blade receptacle; 
           [0022]      FIG. 6   b  is a perspective view of the angled portable chamfer tool of  FIG. 6   a  having a tenon/peg taper length sight and associated metering marks; 
           [0023]      FIG. 7  is a perspective view of a portable drill interface for a portable chamfer tool having a pin or peg connection system; 
           [0024]      FIG. 8  is a perspective view of a portable drill interface for a portable chamfer tool having a threaded connection system; and 
           [0025]      FIG. 9  is an assembled rear elevational view of the mortise and tenon joint of  FIGS. 1 and 2  including a peg having matched tapered ends created using a portable chamfer tool of the type shown in  FIGS. 3-8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Referring generally to  FIGS. 3-6   b , a plurality of portable chamfer tools  10  in varying sizes and views is shown. For example, it is contemplated that the chamfer tool  10  may be constructed in sizes including ⅜ inch, ¾ inch, 1 inch, 1 and ½ inch, 2 inch, 3 inch, and the like or may include substantially larger or smaller sizes. Regardless of overall size, each portable chamfer tool  10  includes a cutting passage  12  around which a pair of cutting blade mounts  14  is disposed. It is contemplated that the chamfer tool  10  housing may be formed of a single machined piece of aluminum so that the chamfer tool  10  is structurally rugged and highly portable. It is contemplated that the chamfer tool  10  includes one and, preferably, two or more cutting blades that are reusable and replaceable. For example, a cutting blade  15  ( FIG. 6   a ), for example a steel blade, can be disposed in the blade mount  14  and secured using a screw receptacle  16 . As such, the blade  15  disposed in the cutting blade mount  14  extends into the cutting passage  12  to cut a portion of a workpiece passing through the cutting passage  12  to a diameter equal to a diameter  18  of the cutting passage  12 . The blade mount  14  not only secures the blade  15  in the desired cutting position, it also provides a portal  19  to allow refuse cut from the workpiece to form the tenon or taper to escape the chamfer tool  10 . 
         [0027]    Extending from the cutting passage  12  is a tenon passage  20 . A plurality of sights  22  formed as cutouts or slots is disposed about the tenon passage  20  to allow a user to identify the length of the tenon during cutting. Encircling the exterior of the tenon passage  20  is a plurality of index grooves or measuring markers  24 . Extending from an end of the tenon passage  20  opposite the cutting passage  12  is a hexagonal peg  26  configured to be engaged by a traditional hand drill (not shown). 
         [0028]    In operation, a workpiece requiring a taper or a tenon is fed into the cutting passage  12 . As the workpiece enters the cutting passage  12 , the cutting blades  15  disposed in the cutting blade mounts  14  engage the workpiece. Accordingly, the workpiece is cut to form a taper extending from the original workpiece diameter to a diameter equal to the diameter  18  of the cutting passage  12 . 
         [0029]    Once cut, the workpiece passes from the cutting passage  12  into the tenon passage  20 . As the workpiece extends into the tenon passage  20  it passes into operator view through the sights  22 . Accordingly, by viewing the workpiece as it passes into the tenon passage  20 , an operator can quickly estimate the length of the tenon formed on the workpiece. In the embodiments illustrated in  FIGS. 3-6   b , the chamfer tool  10  includes two sights  22  disposed on opposite sides of the tenon passage  20 . However, it is contemplated that the chamfer tool  10  may include at least four sights  22 . That is, by including four or more sights  22  disposed evenly around the tenon passage  20 , the length of the tenon extending through the tenon passage  20  is continuously visible to the operator as the chamfer tool  10  rotates. 
         [0030]    To allow the operator to immediately and accurately identify the actual length of the tenon during the cutting process, the operator needs to simply compare the extent of the tenon passing through the sights  22  to the measuring markers  24 . As shown, the measuring markers  24  are positioned along the exterior of the tenon passage  20  to form a point of reference to which an operator can compare the workpiece extending through the sights  22  to immediately and accurately identify the actual length of the tenon during the cutting process. 
         [0031]    While the measuring markers  24  are shown as a plurality of grooves evenly spaced along and completely encircling the exterior of the tenon passage, numerous variations may be made while still achieving the desired functionality. For example, instead of grooves, the measuring markers  24  may be painted on the exterior of the tenon passage  20  or other non-etched marks may be formed on the exterior of the chamfer tool  10 . Furthermore, while it is preferable that measuring markers  24  completely encircle at least the tenon passage  20  so that the measuring markers  24  are continuously visible as the chamfer tool  10  rotates, it is contemplated that the measuring markers  24  may be reduced to encircle less than the whole of the tenon passage  20  while still providing the desired functionality. Additionally, while the measuring markers  24  are shown as being evenly spaced, it is contemplated that the measuring markers  24  may be advantageously unevenly spaced for some applications. For example, it is contemplated that the measuring markers  24  may be disposed at reducing intervals extending from the cutting passage  12  to the hexagonal peg  26 . In this regard, the measuring markers  24  present the operator with a measurement that is less accurate when the workpiece enters the tenon passage  20  but becomes more accurate as the workpiece moves through the tenon passage  20 . Also, it is contemplated that the measuring markers  24  may be accompanied with etched or painted measurement values indicating the length of the tenon created when the workpiece extends to a given measuring marker  24 . 
         [0032]    Additionally, it is contemplated that taper shape created by the chamfer tool  10  may be varied by adjusting a shape of the chamfer tool  10  and the position of the blades when secured therein. For example, as shown in  FIGS. 3-6   b , the diameter of the cutting passage  12  and the tenon passage  20  may be varied. Similarly, the shape and mounting position of the cutting blades as well as the interface between the cutting passage  12  and the tenon passage  20  may be varied. In this regard, as shown  FIGS. 3-5 , a rounded cutting blade may be mounted in a rounded cutting blade mount  14  to create a rounded taper on the workpiece. On the other hand, as shown in  FIGS. 6   a  and  6   b , a flat blade  15  may be mounted in a flat blade mount  14  to create a planar angled taper on the workpiece. Accordingly, it is contemplated that the blade mount  14  may be configured to receive a wide variety of cutting blades such as rounded, straight, simple, or complex blades. 
         [0033]    Furthermore, as shown in  FIGS. 3-4   d , the hexagonal peg  26  may be integrated into the chamfer tool  10 . However, as shown in  FIGS. 5-8 , it is also contemplated the hexagonal peg  26  may be formed as an independent device that is configured to engage the chamfer tool  10 . That is, as shown in  FIGS. 5-6   b  and  7 , the tenon passage  20  may extend through the end of the chamfer tool  10 . In this regard, the hexagonal peg  26  can be positioned to form an end cap of the tenon passage  20  and be held in place by a roll pin extended through a pin shaft  28  in the chamfer tool  10  and corresponding pin shaft  30  in the hexagonal peg  26 . Alternatively, referring to  FIG. 8 , it is contemplated that the hexagonal peg  26  may include a threading  31  that is configured to engage a reciprocal threading (not shown) formed in the chamfer tool  10 . 
         [0034]    Also, though the sights  22  are shown in  FIGS. 3-6   b  as extending along the tenon passage  20  and terminating prior to the cutting passage  12 , it is contemplated that the sights may be extended into the cutting passage  12  to enable a user to determine the length of a taper formed by the chamfer tool  10  prior to forming a tenon. In this regard, the measuring markers  24  may also be extended into the cutting passage  12 . 
         [0035]    It is contemplated that the chamfer tool  10  may be used in a variety of applications. In particular, referring to  FIG. 9 , the portable chamfer tool described above with respect to  FIGS. 3-8  can be used to create a second tapered end  9  that is matched to the preformed tapered end in an assembled mortise-and-tenon joint  1 . That is, using the above-described chamfer tool, each builder of a timber home or building can quickly and easily match the blunt end  8  of the peg  4  with the preformed taper  7  profile created at the factory. Specifically, after assembling a traditional mortise-and-tenon joint ( FIG. 2 ), a builder can engage the above-described chamfer tool in a cordless or electric drill to rotate the chamfer tool about the blunt end  8  of the peg  4 , thereby forming a taper  9  easily matched to the preformed taper  7  because the builder can use the aforementioned measuring markers to determine when a taper matching the factory preformed taper  7  has been created without having to repeatedly remove the chamfer from the peg  4  to measure the taper. 
         [0036]    The present invention has been described in terms of the preferred embodiment, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention. Therefore, the invention should not be limited to a particular described embodiment.