Patent Publication Number: US-9840019-B2

Title: Wood cutting blade with adjustment legs and blade positioning assembly

Description:
This application claims the benefit and priority of U.S. Provisional Patent Application No. 61/894,966 filed Oct. 24, 2013. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to the processes of wood cutting, chipping, peeling and slicing and to the beveled metal blades that are used with such processes. More specifically, the present invention relates to a beveled metal blade that has adjustment legs for use within a fixed or rotatable blade mount base or head. It also relates to a blade positioning assembly that is drawn to that combination. 
     BACKGROUND OF THE INVENTION 
     The use of beveled metal blades is well known. A fixed or rotary base or head that holds one or more blades within the base or head is also well known. Such structures will be collectively referred to herein simply as “blade holders” or a “blade holder.” The blade holder typically comprises a linear aperture having a rear surface and further comprises means and structure for securely clamping the blade for use. The precise type of blade holder with which the present invention is used is not a limitation of the present invention. 
     One obvious problem with the use of beveled metal blades in applications where wood is processed is that the cutting edge of the blade, or blades, becomes worn or dulled over time. Indeed, such beveled blade edges become worn to the point that the process becomes inefficient, which necessarily requires re-sharpening of the bevel or complete replacement of the blade or blades. 
     In view of such blade wear, however, it is far more desirable and economical to remove the blade or blades from the blade holder, sharpen the beveled cutting edge or edges, and then re-secure the blade or blades within the blade holder. However, it is also well known that blade sharpening results in the loss of blade material, which serves to shorten the depth of the blade. Obviously, re-insertion of the shortened blade into the blade holder could result in a blade that will not rest against the rear surface of the holder in which case the blade is effectively too short for its intended use. While shims and spacer blocks can be inserted behind the blade, or melted babitt metal can be poured behind the blade, it is difficult to properly position the blade using the former methods unless the shims or blocks exactly match the amount of blade material lost during the sharpening process. 
     Accordingly, it is an object of the present invention to provide a means for compensating for the metal material that is lost during the process of sharpening of the beveled blade edge while also allowing the blade to continue to be used as intended. It is another object to provide such a means that can be used easily and quickly, that uses a minimal number of steps and tools to do so and that allows the blade to have an extended useful life even though the metal cutting blade is shortened during the sharpening process. It is a further object to provide the structure for compensating for metal lost during the blade sharpening process that eliminates the need for shims, spacer blocks or other means that would otherwise be needed to position the blade within the blade holder. 
     SUMMARY OF THE INVENTION 
     The blade and assembly of the present invention has obtained these objects. It provides for a blade that has a front beveled cutting edge and at least two recesses defined within the back, or non-cutting edge, of the blade. It is also within the scope of the present invention to provide a back blade edge without recesses which would provide substantially the same functionality as described in this disclosure, the blade and assembly of the present invention being fully functional in such alternative embodiment. 
     A bore in the form of a substantially cylindrical cavity or circular aperture extends inwardly into the blade from each recess, or inwardly from the rear of the blade where no recesses are provided, the apertures having axes that are defined in planes that are parallel to first and second planar surfaces of the blade. However, the blade of the present invention is not limited to cylindrical cavities or circular apertures in this regard. A plurality of “T-shaped” legs is also provided, each leg having a cross bar or “foot” that is secured at one end of a rod. In the preferred embodiment, three such legs are used, although the present invention is not limited to that number. Further, the legs are not limited strictly to a T-shape as other shapes could be functionally adapted for use in the preferred embodiment. 
     The rod of each leg is used for insertion into the blade apertures, the profile of the rod substantially matching that of the bore. This allows the blade to be extended forwardly or rearwardly so as to properly position the blade within the holder. Means for fixing the position of the rod within the bore is also provided. 
     The foregoing and other features of the metal blade and the blade assembly of the present invention will be apparent from the detailed description that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top plan view of a metal cutting blade that is constructed in accordance with the present invention and showing the blade prior to insertion of the T-shaped legs into the blade. 
         FIG. 2  is right side elevational view of the blade shown in  FIG. 1 . 
         FIGS. 3A and 3B  are top and end views, respectively, of an exemplary short adjusting leg used with the blade shown in  FIGS. 1 and 2 . 
         FIGS. 4A and 4B  are top and end views, respectively, of an exemplary medium adjusting leg used with the blade shown in  FIGS. 1 and 2 . 
         FIGS. 5A and 5B  are top and end views, respectively, of an exemplary long adjusting leg used with the blade shown in  FIGS. 1 and 2 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings in detail, wherein like numbered elements refer to like elements throughout,  FIGS. 1 and 2  illustrate a representative structure, generally identified  10 , which is a preferred embodiment of a beveled metal blade that is fabricated in accordance with the present invention. 
     As shown, the blade  10  comprises a beveled front cutting edge  11  and a rear surface  12 . This rear surface  12  is that portion of the blade  10  that can rest against the rear surface of the blade holder (not shown). The blade  10  is also defined by a planar top surface  13  and a planar bottom surface  14 . It should be noted that the surfaces are defined as “top” and “bottom” for purposes of orientation in this detailed description and such orientations are not limitations of the present invention. For example, such surfaces could also be identified as a “first” and a “second” planar surface and still be within the scope of the present invention. 
     In the preferred embodiment, the rear surface  12  has at least two rectangular-shaped recesses  15   a ,  15   b , although the recesses are not limited to that shape and the recesses could be eliminated altogether in an alternative embodiment. Extending inwardly of the blade  10  from each recess  15   a ,  15   b  is a primary bore in the form of a substantially cylindrical cavity or circular aperture  16   a ,  16   b , respectively. In the embodiment where the recesses are eliminated, the primary bores  16   a ,  16   b  would simply extend inwardly from the rear surface  12  of the blade  10 . Each primary bore or aperture  16   a ,  16   b  has an axis, the axis being substantially parallel to the planar top surface  13  and the planar bottom surface  14  of the blade  10 . It is to be understood, however, that the primary apertures  16   a ,  16   b  need not be cylindrical cavities or bores and the present invention is not limited to a circular aperture structure as disclosed herein. 
     Accessible from the bottom surface  14  and disposed below each primary aperture  16   a ,  16   b  are a plurality of threaded secondary bores or apertures  17   a ,  17   b ,  18   a ,  18   b ,  19   a ,  19   b  which are used as points for receiving a like-threaded set screw (not shown). Each secondary bore is configured to intersect a primary bore perpendicularly. That is, each secondary bore also has an axis, such axis being substantially perpendicular to the axis of the primary bore that the secondary bore is associated with. It is also to be understood that other fastening means could be utilized in accordance with the spirit and scope of the present invention. It is also to be understood that the secondary bores  17   a ,  17   b ,  18   a ,  18   b ,  19   a ,  19   b  could also be disposed above the blade  10  and still come within the scope of the present invention, such position being equally effective in application. Further, and where the thickness of the blade  10  is relatively thin, it is also possible to align the secondary bores  17   a ,  17   b ,  18   a ,  18   b ,  19   a ,  19   b  in such a way that the bores are accessed from the ends  8 ,  9  of the blade  10 . See  FIG. 1 . In this configuration, the primary bores  16   a ,  16   b  would be disposed closer to the ends  8 ,  9  of the blade  10 . 
     In the preferred embodiment, a series of “T-shaped” legs are intended to be received within the primary bores  16   a ,  16   b . It is to be understood that alternative shapes of legs could be used, such as “L-shaped” legs, “U-shaped” legs, linear posts (which would simply be the “longitudinal rods” mentioned below) and the like. All such embodiments are within the scope of the present invention provided the structure is receivable within the primary bores  16   a ,  16   b  and the need for inserting any shims or spacer blocks behind the blade or pouring melted babitt metal behind the blade is eliminated. 
     Referring to  FIGS. 3A and 3B  of the preferred embodiment, they illustrate a short T-shaped adjustment leg, generally identified  20 . The short adjustment leg  20  comprises a cross-bar  22  from which a longitudinal rod  24  extends perpendicularly. The size of the rod  24  is slightly smaller than the size of the primary bores or apertures  16   a ,  16   b  such that the rod  24  can be easily received by, slid into and withdrawn from such primary bores or apertures. The cross-bar  22  of the leg  20  is dimensioned such that a portion of such cross-bar  22  fits within either of the recesses  15   a ,  15   b.    
     Referring to  FIGS. 4A and 4B , they similarly illustrate a medium T-shaped adjustment leg, generally identified  30 . The medium adjustment leg  30  comprises a cross-bar  32  from which a longitudinal rod  34  extends perpendicularly. The size of the rod  34  is also slightly smaller than the size of the primary bores or apertures  16   a ,  16   b  such that the rod  34  can be easily received by, slid into and withdrawn from such primary bores or apertures. The cross-bar  32  of the leg  30  is dimensioned such that a portion of the cross-bar  32  fits within either of the recesses  15   a ,  15   b.    
     Referring to  FIGS. 5A and 5B , they illustrate a long T-shaped adjustment leg, generally identified  40 . The long adjustment leg  40  comprises a cross-bar  42  from which a longitudinal rod  44  extends perpendicularly. The size of the rod  44  is slightly smaller than the size of the primary bores or apertures  16   a ,  16   b  such that the rod  44  can also be easily received by, slid into and withdrawn from such primary bores or apertures. The cross-bar  42  of the leg  40  is dimensioned such that a portion of the cross-bar  42  fits within either of the recesses  15   a ,  15   b.    
     In application, the blade  10  is held within the blade holder (also not shown). When the beveled front cutting edge  11  of the blade  10  is worn to the point that it needs to be sharpened, the blade  10  is unclamped and withdrawn from the blade holder. Because sharpening decreases the depth of the blade  10 , some adjustment or compensation must be made for that decrease in blade depth. In the blade  10  and assembly of the present invention, adjustment of the rods  24 ,  34 ,  44  within their respective primary bores or apertures allows the blade  10  to be positioned relative to the rear surface of the holder against which the rear surface  12  of the blade  10  would normally rest. This allows for precise adjustment of the blade  10  within the blade holder prior to clamping of the blade  10  under high pressure within the blade holder, such as between a mount base and a clamping plate, for example. 
     By way of specific example, and to “fine adjust” the blade  10  relative to blade holder, a short adjustment leg  20  can first be inserted into each of the primary apertures  16   a ,  16   b  to a depth as is necessary. In this way, the cross-bar  22  need not be received within the recesses  15   a ,  15   b  or positioned within them. The rod  24  of the leg  20  can then be secured in a position within the primary bores or apertures  16   a ,  16   b  to match the blade depth that needs to be compensated for. This is accomplished by using the secondary threaded secondary bores or apertures  17   a ,  17   b ,  18   a ,  18   b ,  19   a ,  19   b  as points for receiving like-threaded set screws (also not shown) which hold the rods  24 ,  34 ,  44  in place. Again, it is to be noted that the fastening means for securing the rods  24 ,  34 ,  44  within the primary bores or apertures  16   a ,  16   b  is not limited to threaded set screws and like-threaded apertures  17   a ,  17   b ,  18   a ,  18   b ,  19   a ,  19   b . Other fastening or fixing means are contemplated to be within the scope of this invention. The embodiment shown is only one alternative embodiment that could be configured in accordance with the present invention. 
     Throughout the useful life of the blade  10 , the other legs  30 ,  40  can be used in similar fashion to further extend the beveled front cutting edge  11  of the blade  10  into its desired or required position. In this fashion, the blade  10  can be used in combination with the adjustment legs  20 ,  30 ,  40  throughout the useful life of the blade  10  to move the blade  10  from a first length of about seven and one-half inches all the way down to a second length of just under four inches, although an almost infinite variety of blade depths could be created using the device and assembly of the present invention, and the present invention is not so limited in this regard. In the process, incremental movement and positioning of the blade  10  can be finely and precisely adjusted as is desired or required by the particular cutting application in view of blade wear.