Abstract:
An arrow barrel for shooting a ball bearing comprising: a shaft having a tail end and a head end opposite the tail end, the shaft being substantially cylindrical and hollow from the tail end to the head end and configured to receive the ball bearing; and a nock body coupled to the tail end of the shaft, the nock body having a bowstring end and an ammunition end opposite the bowstring end, the bowstring end comprising a bowstring notch configured to receive a bowstring, wherein a portion of the nock body is magnetized such that the nock body retains the ball bearing throughout the drawing of the bowstring and releases the ball bearing upon the release of the bowstring.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to co-pending U.S. Provisional Patent Application Ser. No. 60/821,661, filed Aug. 7, 2006, which is hereby incorporated by reference as if set forth herein. 
     
     SUMMARY 
       [0002]    The present invention relates to arrows. More particularly, the present invention relates to an arrow barrel for shooting ball bearing ammunition. 
     
     
       DESCRIPTION OF THE DRAWINGS 
         [0003]      FIG. 1  is a side view of an exemplary nock body in accordance with the present invention; 
           [0004]      FIG. 2  is a cross-sectional side view of the exemplary nock body shown in  FIG. 1 ; 
           [0005]      FIG. 3  is a cross-sectional side view of an exemplary arrow barrel in accordance with the present invention; 
           [0006]      FIG. 4  is a side view of the exemplary arrow barrel shown in  FIG. 3 ; 
           [0007]      FIG. 5  is a side view of an exemplary arrow barrel having a tail-hook in accordance with the present invention; 
           [0008]      FIG. 6  is a top view of the exemplary arrow barrel shown in  FIG. 5 ; 
           [0009]      FIG. 7  is a cross-sectional side view of another exemplary arrow barrel configured for a crossbow in accordance with the present invention; 
           [0010]      FIG. 8  is a side view of an exemplary closing end cap in accordance with the present invention; 
           [0011]      FIG. 9  is a side view of the closing end cap of  FIG. 8  disposed on a nock of the present invention; 
           [0012]      FIG. 10  is a side view of an exemplary nock in accordance with the present invention; 
           [0013]      FIG. 11  is a side view of an exemplary arrow barrel installed on a bow in accordance with the present invention; 
           [0014]      FIG. 12  is a close-up side view of an exemplary arrow barrel installed on a bow in accordance with the present invention; 
           [0015]      FIG. 13  illustrates an exemplary closing end cap in accordance with the present invention; 
           [0016]      FIG. 14  is a perspective view of an exemplary arrow barrel in accordance with the present invention; 
           [0017]      FIG. 15  is a side view of a male part of a threaded closing end cap; 
           [0018]      FIG. 16  is a side view of a female part of a threaded closing end cap; and 
           [0019]      FIG. 17  is a side view of the male part of  FIG. 15  threaded into the female part of  FIG. 16 . 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Persons of ordinary skill in the art will realize that the following disclosure is illustrative only and not in any way limiting. Other embodiments of the invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. 
         [0021]      FIGS. 1-6  illustrate the components of arrow barrel  2 , with like components numbered alike. Arrow barrel  2  comprises shaft/barrel  20  and tailhook nock  4 . Nock  4  may be an independent component coupled to shaft  20 , or alternatively, nock  4  may be integrally formed with shaft  20 . In a preferred embodiment, both nock  4  and shaft  20  are substantially cylindrical in shape. 
         [0022]    Nock  4  comprises an ammunition end  10  and a bowstring end  8  opposite ammunition end  10 . Ammunition end  10  is configured to receive and retain ammunition such as standard ball bearing ammunition  6  through the use of magnetization. Bowstring end  8  is configured to receive and retain the bowstring, or drawstring, of any bow known in the art, including, but not limited to, compound bows, recurve bows, crossbows, composite bows, longbows, and flatbows. It is noted that bowstring and drawstring are used interchangeably herein. In a preferred embodiment, the drawstring is a multi-stranded string of either Dacron, Kevlar or Fastflight looped to the bownocks or teardrops (compound bows). However, it is contemplated that any drawstring known in the art may be used. 
         [0023]    Bowstring end  8  of nock  4  comprises means for receiving and retaining a drawstring. In a preferred embodiment, nock  4  comprises drawstring retaining hole  12  and drawstring retaining slot  14  disposed proximate bowstring end  8 . Retaining slot  14  communicates with retaining hole  12  so that a drawstring may be passed through retaining slot  14  into retaining hole  12 . Preferably, retaining hole  12  is disposed at a height proximate the center of nock  4 . 
         [0024]    Nock  4  may be slipped over a standard bow drawstring, with the drawstring passing through retaining slot  14  and being retained in retaining hole  12 . When the drawstring is pulled back and released to shoot, the drawstring secures nock  4 . By securing nock  4 , the drawstring also secures shaft  20 . In this fashion, barrel  2 , including nock  4  and shaft  20 , moves forward quickly after the drawstring is released. As the drawstring and barrel  2  move forward, the drawstring eventually applies a braking force to barrel  2  at retaining hole  12 , resulting in barrel  2  stopping as suddenly as the drawstring. The ammunition such as ball bearing  6 , which is retained magnetically at ammunition end  10 , is thrust toward the target with enough force to overcome the magnetic attraction. The ammunition is thereby projected towards the target, while barrel  2  stays with the drawstring. 
         [0025]    Retaining slot  14  is preferably smaller in diameter than retaining hole  12  in order to prevent the drawstring from accidentally exiting retaining hole  12  and retaining slot  14 . However, it is contemplated that the respective sizes of retaining slot  14  and retaining hole  14  may vary. A simple slotted plastic end cap  52  may also be used to cover slot  12  in order to prevent the drawstring from exiting. As seen in  FIGS. 8 and 9 , cap  52  may be configured to fit over bowstring end  8 , accommodate drawstring  32  and block drawstring  32  from leaving retaining hole  12 . Cap  52  is preferably substantially cylindrical in shape and comprises a slot  54  for receiving and retaining drawstring  32 . 
         [0026]    As mentioned above, the ammunition is retained magnetically at ammunition end  10  so that the ammunition may be held against nock  4  until the drawstring is pulled and released. This magnetic attraction may be achieved in a variety of ways. For example, magnetized nock insert  5 , such as a magnetized steel rod, may be disposed inside nock  4 . This magnet holds the ammunition without barrel  2  having to be oriented at least horizontal to the ground to prevent the ammunition from sliding away from nock  4  and out of shaft  20 . As seen in  FIG. 2 , magnetized insert  5  is preferably set back from the ammunition with only the nock  4 , preferably made out of aluminum or some other non-magnetic metal, touching the ammunition so that the magnet is not too strong in holding the ammunition in place. In another embodiment, the entire nock  4  could be one weakly magnetized piece. 
         [0027]    Shaft  20  comprises a tail end  24  and a head end  26  opposite tail end  24 . Preferably shaft  20  is preferably hollow from head end  26  to tail end  24 , or from head end  26  to nock  4 , thereby forming shaft interior  22 . Shaft interior  22  is configured to allow ammunition to pass through it. In a preferred embodiment, the diameter of shaft interior  22  is slightly larger than the diameter of the ammunition. Shaft  20  may be formed from an aluminum arrow such as an Easton  2512  that is epoxy glued to nock  4 , which may be inserted about ¾ of an inch inside shaft  20  as seen in  FIG. 3 . 
         [0028]    Tail end  24  is configured to retain or house nock  4 . Although the figures illustrate nock  4  as an independent piece that is coupled to tail end  24 , it is contemplated that nock  4  may alternatively be integrally formed with tail end  24 . 
         [0029]    Head end  26  comprises exit aperture  29 . Exit aperture  29  is an opening that communicates with shaft interior  22  and is configured to allow the ammunition to pass through it. In a preferred embodiment, exit aperture is substantially circular in shape and its diameter is slightly larger than the diameter of the ammunition. Exit aperture  29  provides an opening on shaft  20  from which the ammunition may be shot. Exit aperture  29  may also be used as a location for the user to load the ammunition. 
         [0030]    Shaft  20  may also comprise loading hole  28  disposed in between ammunition end  10  of nock  4  and exit aperture  29  of shaft  20 . Loading hole  28  is an aperture that communicates with shaft interior and is configured to allow the user to load the ammunition without having to drop it in at exit aperture  29 . The user simply places the ammunition through loading hole  28  and into shaft interior  22 . Barrel  2  may then be manipulated in order to direct the ammunition to the ammunition end  10  of nock  4  where it is magnetically retained until it is shot. In a preferred embodiment, loading hole  28  is substantially circular in shape and its diameter is slightly larger than the diameter of the ammunition. 
         [0031]    It is contemplated that a forward hold down strap may be used to provide stability for barrel  2 . This strap may comprise two pieces of Velcro looped around the bow or crossbow and barrel  2  in order to hold barrel  2  down and prevent it from bouncing around. 
         [0032]    The barrel of the present invention may also be configured to accommodate a crossbow. A crossbow is usually cocked by pushing the front end against the ground, then loading the arrow. The string is then inside the trigger mechanism, so the user cannot slide the nock over the string. On some models that cock differently, such as pulling the string back by hand, you can pre-load the arrow using the nock alone. 
         [0033]    Nock  4  may comprise crossbow drawstring notch  16  disposed at bowstring end  8 . Crossbow drawstring notch  16  is simply a notch that accepts a crossbow drawstring. Either nock  4  or shaft  20  may comprise crossbow drawstring tailhook slot  18  for adjustably retaining crossbow drawstring tailhook  30 . As seen in  FIGS. 5 and 6 , crossbow drawstring tailhook  30  is a rod, preferably comprising a hook shape, which is used with a crossbow drawstring  32  in order to secure barrel  2  to the crossbow drawstring  32 . Crossbow drawstring tailhook  30  is adjustably disposed in tailhook slot  18 . Tailhook slot  18  is preferably configured to allow tailhook  30  to be moved towards bowstring end  8  and away from bowstring end  8 . Additionally, tailhook slot  18  is configured to secure tailhook  30  when tailhook  30  is in a position away from bowstring end  8 . As seen in  FIG. 1-5 , tailhook slot  18  may extend in a direction towards head end  26 . Tailhook slot  18  may then extend in a downward direction, after which it may terminate by briefly extending in a direction towards bowstring end  8 . However, it is contemplated that tailhook slot  18  may be configured in a variety of other ways in order to adjustably retain tailhook  30 . 
         [0034]    In a preferred embodiment, the crossbow bolt barrel is placed on the crossbow and into the trigger mechanism after it is cocked. Tailhook  30  is then moved rearward at the top of slot  18 . The rear of tailhook  30  may then pass over drawstring  32 . Once the rear of tailhook  30  has been placed over drawstring  32 , the front of tailhook  30  may be moved forward towards head end  26 , then downward, and finally rearward into the shorter part of slot  18 , thereby being secured in a position where it is hooked onto drawstring  32 . Since tailhook  30  is hooked onto drawstring  32 , tailhook  30  applies a braking force onto barrel  2  after drawstring  32  is released by the crossbow. In this fashion, tailhook  30  and tailhook slot  18  provide the same function as retaining hole  12 . 
         [0035]    The diameter of a crossbow bolt is smaller than a standard arrow for a recurve or compound bow. In order to handle all of these bows, the present invention provides crossbow arrow barrel  40 .  FIG. 7  illustrates crossbow arrow barrel  40 . Crossbow arrow barrel  40  is similar to arrow barrel  2 , with like components numbered alike. Although shaft  20  of crossbow arrow barrel  40  is the same as shaft  20  of arrow barrel  2 , nock  42  of crossbow arrow barrel  40  comprises a slightly different design than nock  4 . 
         [0036]    Nock  42  comprises a bowstring end  44  and an ammunition end  46  opposite bowstring end  44 . Since bowstring end  44  is the end that is placed into the trigger mechanism of the crossbow, it is smaller in diameter than the portion of nock  42  that does not go into the trigger mechanism. As seen in  FIG. 7 , this smaller diameter extends from bowstring end  44  to a substantial distance away from bowstring end  44 . Preferably this smaller diameter portion  56  is substantially cylindrical in shape and has its bottom surface aligned with the bottom surface of shaft  20 . Since drawstring end  44  is off-center with respect to shaft  20 , the height of retaining hole  12  may be centered with respect to shaft  20  rather than nock  42  in order for retaining hole  12  to line up with the drawstring on a recurve or compound bow. 
         [0037]    In a preferred embodiment, nock  42  comprises an upper offset  48  and a lower offset  50  where smaller diameter portion  56  meets shaft  20 . Upper offset  48  represents the raising of the end of nock  42  to increase the diameter of nock  42  to the standard arrow size of shaft  20 . Lower offset  50  represents the change in diameter of nock  42  so that the bottom of shaft  20  is flush with the bottom of nock  42  when arrow barrel  40  is installed on a crossbow. 
         [0038]    Although  FIG. 7  does not show all of the components shown in  FIGS. 1-6 , it is contemplated that arrow barrel  40  may comprise any of the components of arrow barrel  2  that are consistent with the basic principles of arrow barrel  40  such as loading hole  28 . 
         [0039]      FIG. 10  shows a side view of an exemplary nock in accordance with the present invention.  FIG. 11  shows a side view of an exemplary arrow barrel installed on a bow in accordance with the present invention.  FIG. 12  shows a close-up side view of an exemplary arrow barrel installed on a bow in accordance with the present invention.  FIG. 13  shows an exemplary closing end cap in accordance with the present invention.  FIG. 14  shows a perspective view of an exemplary arrow barrel in accordance with the present invention. 
         [0040]      FIGS. 15-17  illustrate an alternative embodiment of a closing end cap in accordance with the present invention. Male end  70  includes slot  72  for receiving a bow string, and threads  74  on upper and lower portions of male end  70 . Male end  70  fastens inside female end  80  by threading into threaded aperture  82 , thus retaining the bowstring in aperture  76  of male end  70 . Female end  80  can be magnetized or contain a magnet to securely retain ammunition  6  during the draw of a bow string. 
         [0041]    While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention.