Patent Publication Number: US-9410778-B2

Title: Expandable broadhead having tip formed as an integral portion of a steel or stainless steel ferrule

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/788,609, filed on Mar. 7, 2013, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/748,954, filed Jan. 4, 2013, herein incorporated by reference in its entirety. 
    
    
     FIELD OF EMBODIMENTS OF THE PRESENT INVENTION 
     Embodiments of the present invention relate to an archery expandable broadhead and, more particularly, to a through-the-body expandable broadhead having a steel or stainless steel body with an integrated machined tip. 
     BACKGROUND OF EMBODIMENTS OF THE INVENTION 
     Known through-the-body expandable broadheads can have a cut on contact tip with either an aluminum or titanium ferrule. The cut on contact tip consists of a sharpened double edged piece of steel inserted into the either aluminum or titanium ferrule body that is held in place with a threaded fastener. An example of such a broadhead is shown, for example, in U.S. Pat. No. 8,197,367, which is incorporated herein by reference. 
     Through-the-body expandable broadheads can also have a chisel tip, in which chisel tip is pressed or otherwise conventionally secured into an aluminum ferrule. An example of such a broadhead is shown, for example, in U.S. Pat. No. 6,540,628, which is incorporated herein by reference. While this offers some advantages over the cut on contact expandable broadheads, these tips generally lack to the sharpness and therefore cutting advantages from a cut on contact tip. 
     However, neither types of these broadheads have a tip that is machined as an integral part of a steel or stainless steel ferrule. There is a need for such a broadhead, as such a broadhead advantageously provides greater structural integrity than an insert steel blade, thereby making the head more durable on impact. Other advantages of a broadhead having a tip that is machined as an integral part of a steel or stainless steel ferrule will be apparent as described herein. 
     SUMMARY OF EMBODIMENTS OF THE INVENTION 
     Embodiments of the present invention have a ferrule  102 ,  301  preferably made from steel or stainless steel, and an integral tip  104  that is machined as an integral part of the ferrule  102 ,  301 . This aspect of the design of various embodiments of the present invention provides several advantages. First, an integral tip  104  provides greater structural integrity than conventional insert steel blades, thereby making the forward portion of the broadhead  100 ,  300  more durable on impact. A steel ferrule  102 ,  301  provides significant structural strength that cannot be obtained with aluminum. 
     Second, an integral tip  104  provides for highly repeatable “centering” of the broadhead  100 ,  300  so that its weight is symmetric about the longitudinal axis of the broadhead  100 ,  300 . Broadheads with conventional steel insert blades that are inserted, for example, into an aluminum ferrule require a steel fastener to pinch the ferrule onto the tip to hold it in place. This requires some clearance for assembly, which allows for off-center positioning. Additionally, the steel fastener is not symmetric on both sides of centerline of the longitudinal axis, causing an off-center mass for the part. An integrated tip in accordance with embodiments of the present invention eliminates these concerns. 
     Third, because the integral tip  104  is self-supporting, it allows the design of the ferrule  102 ,  301  to be such that it has a narrower profile and therefore a greater penetrating capability than broadheads with conventional steel insert blades that are inserted into an aluminum ferrule. 
     Fourth, the integral tip  104  can be made with a profile that allow for a sharper point and therefore greater penetrating ability that could not otherwise be achieved while meeting the structural demands of the broadhead. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of an exemplary 6-40 threaded embodiment of a steel or stainless steel expandable broadhead in accordance with the present invention. 
         FIG. 2  is an exploded perspective view of the 6-40 threaded embodiment of  FIG. 1 . 
         FIG. 3  is a front view of an exemplary 8-32 Archery Manufacturer&#39;s Organization (AMO) standard threaded embodiment of a steel or stainless steel expandable broadhead in accordance with the present invention. 
         FIG. 4  is a first perspective view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 6-40 threaded embodiment. 
         FIG. 5  is a second perspective view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 6-40 threaded embodiment. 
         FIG. 6  is a side view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 6-40 threaded embodiment. 
         FIG. 7  is a first perspective view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 8-32 AMO threaded embodiment. 
         FIG. 8  is a second perspective view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 8-32 AMO threaded embodiment. 
         FIG. 9  is a side view of the integral tip as it appears machined into the ferrule when it is not part of an assembly of a 8-32 AMO threaded embodiment. 
         FIG. 10  is a close in view of the integral tip design as shown in the embodiments of  FIGS. 1-3 . 
         FIG. 11  is a view of a portion of the integral tip design as shown in  FIG. 10 . 
         FIG. 12  is a close in view of the integral tip design as shown in the embodiments of  FIG. 6 . 
     
    
    
     BRIEF DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
       FIG. 1 , generally at  100 , is a front view of an exemplary 6-40 threaded embodiment of an expandable broadhead in accordance with the present invention. The expandable broadhead  100  includes a ferrule  102  with an integral tip  104  and a rear end  106 . The ferrule  102  is preferably made from steel or stainless steel, and the integral tip  104  is machined as an integral part of the ferrule  102 . The rear end  106  preferably includes threads  108  that threadably engage with a conventional arrow shaft. 
       FIG. 2  is an exploded perspective view of the 6-40 threaded embodiment of  FIG. 1 . As shown in  FIG. 2 , the ferrule  102  includes one or more slots  202  adapted to receive one or more rear deploying blades  204   a ,  204   b  (referred to collectively as “ 204 ”). In the illustrated embodiment, a single slot  202  receives both of the rear deploying blades  204 . As used herein, “rear deploying” means rearward translation of blades generally along a longitudinal axis of a broadhead body and outward movement of a rear portion of the blade way from the longitudinal axis. In a rear deploying system the rear portion of the blade typically remains on the same side of a blade pivot axis in both the retracted and deployed configurations. Prior expandable broadheads with rear deploying blades are disclosed in U.S. Pat. No. 6,517,454 (Barrie et al.); U.S. Pat. No. 6,626,776 (Barrie et al.); and U.S. Pat. No. 6,910,979 (Barrie et al.), U.S. Pat. No. 8,197,367 (Pulkrabek, et al.), each of which are hereby incorporated by reference. The rearward translation can be linear, curvilinear, rotational or a combination thereof. The rear deploying blades  204  are slidably engaged with the ferrule  102 . In the preferred embodiment, the blades  204   a ,  204   b  move outward in a camming manner, along a pin  206 , from the ferrule body  102  by a rearward translation that causes interaction between the ferrule body  102  and the blades  204   a ,  204   b . The pin  206  is preferably a threaded fastener, such as the hex fastener that can be removed to permit blade replacement. 
     The integral tip  104  preferably includes a plurality of facets or flat regions  104   a - c , as shown in  FIGS. 1 and 2 . In the illustrated embodiment, the integral tip  104  includes six facets. It is believed that the facets (e.g.,  104   a - c ) increase the aerodynamic stability of the expandable broadhead  100  during flight. The number of facets  104   a - c  can vary with broadhead design and other factors. 
     As shown in  FIGS. 1 and 2 , a collar  110  is provided that retains the blades  204  in place until impact, at which point the collar deforms and/or breaks and allows the blades  204  to expand outward in a conventional manner. When the collar  110  is placed on the ferrule  102 , the collar  110  is positioned over the threaded portion  108 , as shown in  FIG. 2 . Prior collar designs are disclosed in U.S. provisional patent application Ser. No. 61/584,430 (filed Jan. 9, 2012, entitled Broadhead Collars) and U.S. patent application Ser. No. 13/736,680 (filed Jan. 8, 2013, entitled Broadhead Collars), are both incorporated herein by reference in their entirety. 
       FIG. 3 , generally at  300 , is a front view of an exemplary 8-32 AMO standard threaded embodiment of a steel or stainless steel expandable broadhead in accordance with the present invention. The rear end  302  of ferrule  301  preferably includes threads  304  that threadably engage with a conventional arrow shaft. Generally, the standard 8-32 threads  304  are for insertion into an either arrow or crossbow bolt. The 6-40 threaded version shown in  FIGS. 1 and 2  is intended for reduced diameter arrows. 
       FIG. 4 , generally at  400 , is a first perspective view of the integral tip  104  as it appears machined into the ferrule  102 . Facets  104   b  and  104   c  of the integral tip  104  are shown.  FIG. 5 , generally at  500 , is a second perspective view of the integral tip  104  as it appears machined into the ferrule  102 . Facets  104   c  and  104   d  of the integral tip  104  are shown. Hole  502  is shown, which is aligned with hole  402  shown in  FIG. 4 . Hole  402  and opening  502  are positioned on opposing sides of ferrule  102 .  FIG. 6 , generally at  600 , is a side view of ferrule  102  when it is not part of an assembly of a 6-40 threaded embodiment. Facets  104   b - d  are shown, as are slot  202 , rear end  106 , and threads  108 . 
       FIG. 7 , generally at  700 , is a first perspective view of the integral tip  104  as it appears machined into the ferrule  301 . Facets  104   b ,  104   c  are shown.  FIG. 8 , generally at  800 , is a second perspective view of the integral tip  104  as it appears machined into the ferrule  301 . Facets  104   c  and  104   d  of the integral tip  104  are shown. Opening  502  is shown, which is aligned with slot  202  shown in  FIG. 7 . Opening  502  and hole  402  are positioned on opposing sides of ferrule  301 .  FIG. 9 , generally at  900 , is a side view of ferrule  301  when it is not part of an assembly of a 6-40 threaded embodiment. Facets  104   b - d  are shown, as are slot  202 , rear end  106 , and threads  108 . 
       FIG. 10 , generally at  1000 , is a close in view of the integral tip  104  as shown in the embodiments of  FIGS. 1-9 . Facets  104   a - d  are shown, as are blades  204   a  and  204   b .  FIG. 11 , generally at  1100 , is a view of a facets  104   a  and  104   b  as generally shown in  FIGS. 1-9 .  FIG. 12 , generally at  1200 , is a close in view of the integral tip  104  as shown in the embodiments of  FIGS. 1-9 . Facets  104   b - d  are shown, as are blades  204   a ,  204   b.    
     In a preferred embodiment, the ferrules  102 ,  301  of the “through the body” expandable broadheads  100 ,  300  have a weight of 100 approximately grains. Steel alloys that could be used for the ferrule  102 ,  301  (and other elements, such as blades  204   a ,  204   b ) would include 4140, 4240, 43L40, 41L40, and many other high strength steels. Examples of stainless steel alloys that would be appropriate for the ferrule  102 ,  301  (and other elements, such as blades  204   a ,  204   b ) would be 420, 416, and 301 stainless.