Abstract:
The present invention provides a crossbow stringing and cocking device whereby one person may easily and safely draw back the string of a crossbow to engage the trigger mechanism for shooting of a projectile, and may also be utilized to unstring and string the bow. The invention utilizes a pulley system, mounted inside the barrel for convenience and safety.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application 60/621,941 filed Oct. 26, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention relates to crossbows.  
       BACKGROUND OF THE INVENTION  
       [0003]     It is well known that crossbows are difficult to cock due to the powerful limbs that are used by this equipment. Over the centuries various apparatus has been developed to provide an easier method for drawing a bow string for engagement with a trigger mechanism. Such devices have included levers, windlasses, built-in pulley systems that are attached to the stock of the bow as well portable rope and pulley means. All of these devices provided some degree of mechanical advantage.  
         [0004]     Earlier attempts to assist with cocking have been overly complex such as those described in related United States patents all by Bednar, being, U.S. Pat. Nos. 6,286,496, 6,095,128 and 6,874,491. These devices preferably are utilized in connection with additional power sources such as hand cranks, powered motors, or powered screwdrivers to assist the user in cocking the crossbow. Redundancy for safety purposes is also not incorporated into these devices.  
       SUMMARY OF THE INVENTION  
       [0005]     It is an object of the present invention to provide a cocking device that is less expensive to produce than existing systems.  
         [0006]     It is an object of the present invention to provide a cocking device that provides easier storage of the cocking device.  
         [0007]     It is an object of the present invention to provide a cocking device that provides redundancy for safety in the event of breakage of a cable or handle during cocking.  
         [0008]     It is a further object of the present invention to provide a cocking device that is easier to operate than existing devices. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     In order that the invention may be more clearly understood, the preferred embodiment thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which:  
         [0010]      FIG. 1  is a bottom view, partly in section, showing a crossbow with the cocking device;  
         [0011]      FIG. 2  is a close up side view of the string, handle and pulley;  
         [0012]      FIG. 3  is a bottom view, partly in section, showing both tackles engaged with the string;  
         [0013]      FIG. 4  shows a user cocking a crossbow using the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0014]     In order to more clearly understand the present invention part numbers as assigned in the following parts list will be used:  
                                             Part Number   Description                                2   Barrel       3   Prod       4   String       5   Stock       6   Forestock       7   Tackle       8   Handles       9   Opening in Barrel       10   Trigger Latch       11   Cable       12   Spring       13   Trigger Mechanism       14   Stirrup       15   Pulley                  
 
         [0015]     A preferred embodiment of the crossbow-cocking device is illustrated in the drawing figures. The conventional crossbow is shown from different angles, as shown in  FIGS. 1 . &amp;  3 . A user is seen utilizing the cocking mechanism of the present invention is  FIG. 4 . In  FIG. 2 a  close up is shown of the handles  8  and tackles  7 , as stored.  
         [0016]     Such a conventional crossbow has a stock with a first end and a second end, a first side and a second side, and prods or limbs  3  attached proximal to the first end of the main beam or barrel that is mounted within the stock  5 . A string  4  is attached to the prod or limbs and a trigger mechanism  13  located intermediate the first end and the second end of the stock and beam combined length.  
         [0017]     The cocking device is comprised of a pair of guide means each of which have an attaching means, also called tackles  7 , attached to the barrel  2 , as in  FIG. 1 . for removable attachment to the bowstring. Both guide means engage a cord or the like, that has a first and a second end. Each guide means is retractably connected to a cable  11  uncoiled and straight as possible or rope that has been attached to a compact constant force spring  12  for retraction when not in use. Within the barrel  2  of the cross bow the cable  11  or rope has been attached to one of the ends of a constant force spring  12  or other means for retracting.  
         [0018]     By generally simultaneously pulling handles  8  on the first and second ropes or cables the cocking means is extracted at point  9  from the barrel  2  and stretched toward the string  4  of the crossbow. Once the block and tackle are attached to both sides of the crossbow string ( FIG. 4 ) the operator bends down toward the handles  8 , grabs them, and pulls them toward himself while bending upward making sure his foot is in the stirrup  14 . This procedure stretches the string to a point that it is able to engage the trigger latch  10  within the barrel that is located between the first and the second end of the said crossbow leaving it in a state ready to be fired or discharged.  
         [0019]     The typical crossbow generally consists of longitudinally extending main beam, or barrel member  2  and two outwardly extending limb members or member  3 , which extend transversely on opposite sides from main beam or barrel member. The crossbow bowstring  4  is strung between the distal ends of outwardly extending limbs  3 . Stock generally includes a rear portion or tailstock  5  having an integrally formed butt portion that is normally positioned against the user&#39;s shoulder when crossbow is being aimed and/or fired. The stock further includes a forestock  6  for holding the main beam or barrel  2 , which may be integral to the tailstock  5 , or may be provided as a separate member secured therewith.  
         [0020]     In the preferred embodiment shown, the barrel  2  is a separate member which may be formed of a strong but lightweight material such as aluminum. Extruded aluminum allows for the mounting of the cocking system that resides in the hollow chamber or chambers of the extrusion.  
         [0021]     In one example of this invention the cocking device is comprised of a pair of guide means shown generally as handles (left and right) and removable hooks  7  and pulley  15 , also referred to as block and tackle  7 . As can be seen more clearly in  FIG. 1 . the pulley is comprised of a block and a sheave  7 . In the preferred embodiment the main beam or barrel  2  is formed from aluminum but may be made from any suitable material. A cord or cable  11  is provided having a first end and a second end, as illustrated in  FIG. 1  &amp;  FIG. 3 .  FIG. 3  shows the first end of the cable  11  passing through the pulley  15  of the guide means or block and tackle  7  and attached thereafter to a handle  8  to aid in the cocking process. The other end of cable  11  enters the barrel  2  on opposing sides of the same at  9  somewhat rear of the string latching means  10 , from the out side of the barrel  2  continuing to the inside of the extrusion or other and attached thereto  12 .  
         [0022]     In the preferred embodiment a constant force spring  12  is used due to its compact size and its excellent characteristics of equal not increasing force throughout its extension, as would be found in extension of coil springs, elastic or surgical tubing as well, gas or air filled shocks and lastly a spring loaded hub that usually includes a clock type spring that has an increase force as it is wound and needs ample space for mounting or installation of such a hub system.  
         [0023]     Handle  8  is attached for removable attachment to  16  the two are of equal shape in tapered dimensions like male and female, the handle  8  is larger dimensionally than  16 . Both have a complimenting taper with the greater of the tapers facing the butt end, thus the handles are secure due to the fit and secondly by the constant force spring that has a constant force on them in the direction of the larger tapers.  
         [0024]     In the operating position as seen in  FIG. 2 . each guide means  7  is removed from holder  16  that is attached to  2  and pull extracted from hole  9 . Once the length of cable is extracted from the barrel or main beam  2  where it resides when not in use, the hooks or block and tackle  7  are extended toward the prod  3  and attached to the bow string  4 . Each hook is attached at a point adjacent to opposing sides of the barrel. The handles  8  one per side as illustrated are pulled in both hands on separate sides of this barrel with your foot in  14 , the mechanical advantage of the pullies which in this case is 50% between the pair of guide means.  
         [0025]     In the preferred embodiment the cord is made from woven nylon fibers; however, the cord may be constructed of any suitable material, as well using the one pulley per side we have a mechanical advantage of 50%. Anyone skilled in this art would be able to accommodate a multiple pulley system with increased mechanical advantage that could also be used in the extruded chambers; one could also reverse the whole assembly to operate from the opposite end.  
         [0026]     It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above article without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.