Patent Publication Number: US-6669586-B2

Title: Expanding broadhead

Description:
RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application No. 60/348,538, filed Jan. 16, 2002 and incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to an arrowhead and more particularly to a broadhead with extendable/retractable blades. 
     BACKGROUND OF THE INVENTION 
     In the past, various blade extending broadhead arrow tips have been provided and various mechanical arrangements to achieve the radial shifting of the blades affords the change from a compressed, in-flight, blade position to the expanded, wound enlarging position and are found in the prior art. The broadhead of U.S. Pat. No. 6,270,435 (owned by the present assignee) typifies such art. 
     In the past, various blade extending broadhead arrow tips have been provided and various mechanical arrangements to achieve the radial shifting of the blades affords the change from a compressed, in-flight, blade position to the expanded, wound enlarging position and are found in the prior art. Applicants, however, are not aware of any such broadhead which does not include mechanical shifting elements to arrive at the blade position change. 
     SUMMARY OF THE INVENTION 
     The present invention is a new expanding broadhead having ring mounted blades with a selected number of blades commonly mounted on a single or multiple ring which ring moves longitudinally internally of the body of the broadhead and the blades move from an in-flight, compressed position to a hide or flesh cutting, outwardly extending position upon striking a target to enlarge the entrance opening into an animal. 
     The blades of the broadhead are rotatably mounted to a longitudinally moving ring member which is arranged within a longitudinally extending cavity within the body of the broadhead and, further, may be arranged within longitudinally extending slots in the body to allow for a compressed, in-flight position which blades are cammed outwardly from such slots upon the broadhead striking an object. A portion of the blade carrying body or other member affixed to the body at the rear of the slots provides the camming action to the blades. 
     With the arrangement provided herein, the rearward and resulting radial shifting of the blades results from the entry of the broadhead into the object upon contact. The common ring mounting of the blades insures simultaneous movement of the blades. 
     The present invention is a broadhead being attachable to an arrow shaft, including a blade support having an internal passage defined in a blade receiving body, the blade receiving body having a plurality of slots defined therein extending from the internal passage to a blade receiving body external margin and having a camming surface. A translatable ring is disposed in the internal passage, and a plurality of extendable blades, each blade being shiftably coupled to the ring proximate a blade first end and being at least partially disposed in a respective slot when in a blade retracted disposition, a blade second end being cammable outward to a blade extended disposition by interaction with the body camming surface. A method of operating an expandable broadhead is further included. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevation of the expanding broadhead embodying the concepts of the applicants&#39; invention in its compressed, in-flight position; 
     FIG. 2 is a front view thereof; 
     FIG. 3 is a longitudinal section taken substantially along Line  3 — 3  of FIG. 2 in which the tip of the broadhead is separated from the body of the broadhead for illustrative purposes; and 
     FIG. 4 is a longitudinal section similar to that of FIG. 3 but illustrating the broadhead in a partially, blade expanded position. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     In accordance with the accompanying drawings, applicants&#39; broadhead  10  includes a penetrating tip  11  and a blade support  12 . The broadhead  10 , including blade support  12  and tip  11  is secured to an arrow shaft S by threaded  12   a  and shouldered  12   b  longitudinal, rearwardly directed extensions. 
     Tip  11  provides a longitudinally extending body having internal threads on the rearmost end thereof, not shown, with the opposite end of the same being faceted to provide a penetrating end consisting of a plurality of cutting surfaces and edges  11   a ,  11   b . Although the applicants have elected to illustrate four (4) such surfaces  11   a  and edges  11   b  and though the broadhead body  11  illustrated includes three (3) expanding blades and therefore does not reflect this concept, the number of such surfaces  11   a  and edges  11   b  will normally correspond to the number of blades provided on the broadhead blade support  12 . The number of blades is selectively chosen and may include up to, for example, eight (8). Applicants&#39; design will work equally well with various selections. 
     Blade support  12  includes a longitudinally extending generally cylindrical blade receiving body  13  having a front, threaded tip receiving section  13   a  connectable with tip  11  and a rear blade camming section  13   b  having a camming surface  13   c . A longitudinally extending, generally cylindrical internal passage  14  is provided within said blade support  12  and terminates in spaced relation from the threaded front  13   a  and extensions  12   a ,  12   b.    
     A plurality of longitudinal grooves  15  are formed in said blade receiving body  13  and may extend the entire longitudinal dimension of internal passage  14 . The grooves  15  extend from the internal passage  14  to the external margin of the blade receiving body  13 . 
     The illustrated blade mounting ring  16  (see FIGS. 3 and 4) is designed for ease of placement on and removal of blades  17  and is provided to slide freely within said passage  14 . The ring  16  has a hinge point  16   a  corresponding to each of the blades  17 . The hinge points  16   a  are preferably equiangular displaced around the ring  16 . 
     A plurality of blades, each designated  17 , is mounted onto ring  16  for free rotation thereon with a mounting passage  17   a  being hingeably coupled to a respective hinge point  16   a . Each of the blades  17  includes a longitudinally extending body having an inner edge  17   b , a sharpened outer edge  17   c , a forward end  17   d , and a rearward end  17   e  and is of a thickness to be received into and allow movement of the blades within slots  15  of blade receiving body  13 . 
     The width of the blades  17  provides that the blades  17  will extend radially outwardly of the blade support  12  during what is termed an in-flight or retracted position as best shown in FIGS. 1 and 2. In this position, the sharpened outer edge  17   c  is exposed and is generally parallel to the longitudinal axis  18 . The width of the blades  17  also provides that the forward ends  17   d  thereof are exposed in the retracted disposition will impact with an object struck by the broadhead  10  to drive the ring-blade assembly  16 ,  17  rearward to react against the end of slots  15  and camming area  13   b , the blades  17  being driven outwardly to an extended, entrance aperture enlarging position, as depicted in FIG.  4 . During the in-flight or retracted position, the inner edges  17   b  of the blades  17  may be within slots  15 . The rearward end  17   e  of blades  17  may be, as shown, angularly arranged with respect to the inner  17   b , and outer  17   c  edges of the blades  17  such that camming motion for blade expansion is easily initiated upon rearward movement of the ring-blade  16 , 17  assembly. 
     Such camming motion is initiated by the blade leading edge  17   d  striking an object at high speed. Resistance of the object to penetration by the broadhead  10  drives the ring  16  and all the blades  17  rearward (leftward in FIGS.  3  and  4 ). This motion drives the blade rearward end  17   e  against the camming surface  13   c  and shifts the blades  17  from the retracted disposition (FIG.  3 ) to the extended disposition (FIG.  4 ). The blades  17  extend radially outward by the camming action of the interaction of the blade rearward end  17   e  and the camming surface  13   c . Impact of a single blade  17  with an object will result in extension of all the blades  17  since all the blades  17  are joined to the common ring  16 . 
     When in the extended disposition, the camming surface  13   c  supports the blade inner edge  17   b . The blades  17  are caused to stay in the extended disposition during passage of the broadhead  10  through an object as result of the force F1 (see FIG. 4) generated on the leading edge  17   d  and the transverse component of the force F2 generated on the portion of the blade  17  forward of the point of contact with the camming surface  13   c  being greater than the transverse component of the force F3 generated on the portion of the blade  17  rearward of the point of contact with the camming surface  13   c.    
     As depicted in FIG. 3, a retaining member  20 , either cutable or rearwardly displaceable may be provided about the blades  17  to, at least during a portion of the retracted in-flight position, maintain said blades  17  in such position. Such a member  20  would be cut by outward expansion of the blades or simply moved by target contact. Such a member  20  could be, for example, an O-ring or a rubber band. 
     To assemble the broadhead  10 , the blades  17  are first coupled to the ring  16  at the respective hinge points  16   a  to form a ring/blade assembly  16 ,  17 . The ring/blade assembly  16 ,  17  is arranged within passage  14  with the blades  17  arranged in slots  15 . The tip  11  is then threadedly attached to the blade support  12 . With the ring/blade assembly  16 ,  17  in its forwardmost, in-flight, retracted position, the arrow S is ready for shooting. During flight, with or without the mentioned retainer  20 , the blades  17  will remain in slots  15  or in close proximity to the blade support  12 , and upon striking and penetrating an object, a rearward force (forces F1, F2, and F3) is directed to the blades  17 , causing the ring-blade  16 - 17  assembly to move rearwardly, camming the blades  17  into extended position. 
     To reverse this process, the blades  17  will either be radially, inwardly moved to cause forward motion or forwardly moved allowing radial shifting to return to the in-flight, retracted position for a subsequent shooting. In either manner, it is not essential to disassemble the tip  11  from the blade support  12 . It should be noted, however, that the ring/blade assembly  16 ,  17  structure allows for removal and replacement of such assembly  16 ,  17  should one or several of the blades  17  become dull or broken. This is a definite advantage to a hunter as the hunter is not required to remove the broadhead  10  from the arrow shaft S for such repair. 
     The applicants have provided a new and unique, expanding broadhead that relies only upon successful hunting use to activate its intended use. That is to say that the shooting of the broadhead into an object results in the expanding of the blades to effect the desired, entrance opening enlargement for generation of an expanded channel in the object. 
     It will be obvious to those skilled in the art that other embodiments in addition to the ones described herein are indicated to be within the scope and breadth of the present application. Accordingly, the applicant intends to be limited only by the claims appended hereto.