CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation-in-Part of U.S. patent application Ser. No. 15/995,446, filed on Jun. 1, 2018, entitled “Quick-Detachable Multi-Purpose Accessory Mounting Platform,” which is a Continuation-in-Part of U.S. patent application Ser. No. 15/468,101, filed on Mar. 23, 2017, entitled “Quick-Detachable Multi-Purpose Accessory Mounting Platform,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/312,275 filed on Mar. 23, 2016, entitled “Devices and Tools for Improved Hunting,” which are incorporated by reference in their entirety.
FIELD OF THE DISCLOSURE The present disclosure generally relates to hunting mechanisms, and more particularly to a quick-detachable multi-purpose accessory mounting platform.
BACKGROUND Various devices and tools are used in connection with hunting; however, as described herein, these devices and tools have various drawbacks that hinder the hunting experience and results thereof. Examples of some of the drawbacks of each device and tool are separately described.
Autonomous Trap Magazine
Shotgun shooters routinely utilize clay target throwing devices to hone skills necessary to hit moving targets while the targets are in flight. A variety of clay target throwing devices are available to the consumer ranging from hand-operated manual throwers to electrically driven autonomous traps which can launch multiple clay targets simultaneously. Lightweight, portable autonomous traps allow a single shooter the convenience of clay target shooting unaided by a helper, and this style of trap can be easily set-up quickly in the field to mimic specific shooting scenarios. Autonomy is aided by a remotely-located, push-button switch which, when pressed, cycles the trap to launch the clay target. A universal feature of autonomous traps is the hopper in which multiple clay targets are simultaneously stacked prior to the onset of the shooting session.
Each clay target in the stack is gravity fed into the trap separately and automatically, eliminating the need for the shooter to repeatedly reload the trap between shots and freeing the shooter from remaining near the trap during a shooting session. In the case of portable autonomous traps, the hopper is typically disassembled for transportation and storage of the trap. At the shooting site, the hopper must be assembled and mounted onto the trap using hand tools prior to the trap's use. However, clay targets cannot be loaded into the hopper until the hopper is mounted on the trap.
Weathercocking Arrowhead
Broadhead arrowheads include several sharpened blades arranged circumferentially about an arrow tip and may be utilized extensively in the dispatching of medium and large game. In general, there are two types of broadhead arrowheads. The first type is a fixed-blade broadhead arrowhead, incorporating blades that are rigidly attached to the tip of the arrow. The blades of the fixed-blade broadhead arrowhead may be permanently attached to the arrow tip, or they may take the form of replaceable blade elements which can be individually replaced when damaged or dull. The main advantages of the fixed-blade broadhead arrowhead are simplicity and reliability. The main disadvantage of the fixed-blade broadhead arrowhead is that the maximum span of the blades must be kept relatively small to mimic flight characteristics of an arrow equipped with an axisymmetric field point arrow tip that has no blades. The latter is widely used in archery practice and training exercises. The second type of broadhead arrowhead is a mechanical broadhead arrowhead, and it generally may include blades that are held in a streamlined position when the arrow is launched and while in flight. Upon impact, the blades rotate radially outward from the central axis of the arrow to increase the effective span of the arrowhead during penetration and creation of the wound channel. One advantage of a mechanical broadhead arrowhead is that the maximum span of the expanded blades can be greatly increased over that of a fixed-blade broadhead arrowhead. A second advantage is that prior to impact, the blades remain in the closed position; therefore, an arrow equipped with a mechanical broadhead arrowhead will closely mimic the flight characteristics of an arrow tipped with a field point arrowhead. However, these advantages come at the expense of mechanical complexity and system reliability. To be effective, the mechanical broadhead arrowhead must remain in the closed position during launch and flight and must also expand symmetrically and completely during the penetration event.
An examination of the relevant aerodynamics of an arrow in flight follows. An arrow can be described with respect to three major components: the tip, the shaft, and the fletching. During flight, an arrow is subject to disturbances (for instance, when launched from a poorly tuned bow) which may cause the arrow to oscillate about its center-of-gravity (cg) centrally located at a point on the shaft centerline between the tip and the fletching. As the arrow oscillates, a transverse force due to lift is generated at the tip that when multiplied by its distance forward of the cg produces a destabilizing overturning moment about the cg. Similarly, a transverse force generated by the fletching multiplied by its distance aft of the cg counteracts this destabilizing moment by providing a larger, corrective stabilizing moment about the cg in opposition to that generated by the tip. As long as the stabilizing moment is greater that the destabilizing moment, the arrow will tend toward self-correction, i.e., the central axis of the arrow will align with the intended flight path. Thus, it becomes clear why a conventional fixed-blade broadhead arrowhead must be limited in blade span; the larger the blade span, the greater the destabilizing overturning moment produced and the less stable the arrow becomes. If the blade span becomes so large that the destabilizing moment produced forward of the cg is greater than the stabilizing moment produced aft of the cg, as the flight progresses, the arrow will increasingly deviate from the intended flight path.
Smoothbore Shotgun Slug
Slugs designed to be fired from a smoothbore shotgun barrel are typically less accurate than slugs designed to be fired from a shotgun having a rifled bore. Several reasons exist for the inaccuracy of slugs fired from smoothbore barrels. One major reason for the inaccuracy is that the smoothbore slug typically lacks adequate static margin, which can be defined as: (Xcp−Xcg)/L*100%, where Xcg is the axial location of the center of gravity measured from the nose of the projectile, Xcp is the axial center-of-pressure also measured from the projectile's nose, and L is the axial length of the projectile. If the static margin is small or negative (for example, less than 5%), the projectile can easily be diverted from the intended shot line due to a lack of longitudinal stability. Small static margin values are inherent in slugs intended for a smoothbore shotgun barrel, as these slugs are low in aspect ratio and cylindrical in form, and this form does not accommodate means for shifting of the center of pressure rearward as required for increased stability. In addition to limited static margin, another major reason for the inherent inaccuracy of a slug fired from a smoothbore barrel is that no roll moment, or an inconsistent roll moment, is imparted to the slug. Induced rolling reduces impact dispersion by averaging out asymmetric forces imposed on slug during launch and while in flight.
To increase accuracy, many shotguns intended for sporting purposes originally fitted with a smoothbore barrel can be retrofitted with a rifled-bore barrel; however, the cost of the rifled-bore barrel can be of the same order as that of the original shotgun. Along with the cost, another downside to installing a rifled shotgun barrel is that the shotgun then becomes a special purpose firearm intended for use against medium to large game, thus limiting the type of game that can be pursued during an outing in the field. Even though smoothbore shotgun slugs are less accurate, they have the advantage that usually no alterations to the shotgun are necessary. This allows a shotgun having a smoothbore barrel to retain the flexibility of taking both small and large game merely by changing ammunition.
Quick-Detachable Multi-Purpose Accessory Mounting Platform
When hunting with a firearm, it is convenient to have accessories such as a flashlight, infrared spotlight, and/or a remote dog training transmitter easily at hand. This can be accomplished by mounting accessories on the firearm within easy reach of the shooter's non-trigger hand, and in an orientation that allows for immediate operation during the act of both carrying and shooting the gun. Furthermore, conditions such as weather, terrain, intended quarry, day/night or night/day transitions, etc. may change during a hunt. The ability to quickly attach or detach various accessories from the firearm, or to quickly attach or detach the entire mounting platform (with the accessories remaining attached to the platform) allows the hunter to better adapt to the changing conditions. Quick-detach firearm-mounted accessories are in common use for military-style firearms which routinely include features such as integrated Picatinny rails for that purpose. However, in contrast to military-style firearms, firearms intended for sporting use are typically not factory-equipped with mounting points for such accessories.
Glock Magazine Release Button Removal Tool
The as-issued magazine release button on a Glock pistol is often replaced, or in the case of left-handed shooters, reversed, to offer the shooter better operational characteristics when changing magazines. The button is usually operated by pressing inward with the thumb of the shooter's dominant hand, with the motion of the button being transverse to the line of fire. The standard button head on a Glock pistol is relatively small and mounted nearly flush with the frame surface such that operation of the button under stress or during extended training sessions can become difficult. Aftermarket replacement buttons typically offer increased button head surface area, and they may increase the operational travel via greater offset of the button head from the frame.
The release button is held in the frame by a vertically oriented, cantilevered, straight steel rod spring inset into a “V” shaped cavity located in the forward face of the pistol frame's magazine well. The fixed end of the spring is held captive by the cavity walls at the narrow end of the cavity near the bottom of the magazine well. The free end of the spring is located higher up in the magazine well where the wider end of the “V” shaped cavity allows room for the free end of the spring to travel side-to-side. The free end of the spring is contained within a slot in the magazine release button which has an opening near one end to allow the installation of the spring's free end into the slot. The free end of the spring elastically bends side-to-side to initially resist the motion of the release button when depressed, and to return the release button to its original position when released.
Removal of the free end of the spring from the slot in the magazine release button occurs to replace or reverse the release button. Flat-bladed screw drivers and dental picks are common impromptu tools which are used to manipulate the free end of the spring toward, and out of the open end of the slot. Access to the spring can only be had through the top or the bottom of the magazine well, which severely limits access to the spring, and causes poor purchase between the impromptu tool and the side of the spring. In many instances, damage to the polymer frame occurs when the impromptu tool slips away from the spring and strikes the edge of the molded spring cavity; the resultant burrs raised on the inside of the magazine well can adversely affect the release and retention of the magazine.
SUMMARY Embodiments of the present disclosure may provide various devices and tools that may be used in connection with hunting, and certain devices and tools may improve the hunting experience and results thereof. These devices and tools may include an autonomous trap magazine, a weathercocking arrowhead, a smoothbore shotgun slug, a quick-detachable multi-purpose accessory mounting platform, and a Glock magazine release button removal tool.
Some embodiments of the present disclosure may provide a multi-purpose accessory mounting platform comprising: a split barrel clamp positioned parallel to a split ventilated rib clamp; an integral hinge that extends between a face of the split barrel clamp and a face of the split ventilated rib clamp; and one or more thumb screws and one or more threaded inserts that mate together to secure the platform to an object via the split barrel clamp and the split ventilated rib clamp. The platform may further comprise at least one recessed circumferentially arranged mounting pad extending over but not contacting the forearm of the firearm that may provide a location for one or more accessories to be attached to the platform. The one or more accessories may be attached to the platform via hook and loop type fasteners or Picatinny rail sections. The platform may further comprise one or more surfaces along split barrel clamp and the split ventilated rib clamp to provide one or more additional accessory mounting points. The platform also may comprise a rear shelf integrally attached to a rear end of the platform. The rear shelf may further include one or more shelf flats oriented parallel to a face of the at least one recessed circumferentially arranged mounting pad. The platform may be formed from one or more materials selected from the group comprising: styrene, urethane, and polyester. The platform may be manufactured using one or more of the following techniques: plastic molding and 3D printing technology. The at least one recessed circumferentially arranged mounting pad may also include one or more central mounting slots located at a forward end of the at least one recessed circumferentially arranged mounting pad.
Further embodiments of the present disclosure may provide a multi-purpose accessory mounting platform comprising: at least one clamp to receive at least one object; and at least one flat mounting surface attached to the at least one clamp, wherein one or more accessories are mounted to the at least one flat mounting surface using adhesive-backed hook and loop type fasteners or Picatinny rail sections. The at least one clamp may be a friction clamp. The platform may further comprise at least one recessed mounting pad, wherein one or more accessories may be mounted to the recessed mounting pad using adhesive-backed hook and loop type fasteners. The platform also may comprise at least one upper tie down post and at least one lower tie down post to secure at least one accessory via elastic bands laced around the at least one upper tie down post and the at least one lower tie down post.
Additional embodiments of the present disclosure may provide a multi-purpose accessory mounting platform for attachment to a firearm, the platform comprising: at least one clamp that receives a muzzle of the firearm; one or more fasteners that mate together to secure the platform to the firearm via the at least one clamp; at least one recessed attachment pad to secure at least one accessory; and at least one mounting surface to secure at least one accessory. The platform also may include a portal that may receive a sling of the firearm. The at least one clamp may be a barrel clamp and a ventilated rib clamp. The platform may further include at least one shelf that may provide a flex point for initial alignment of the firearm when being attached to the platform. The one or more fasteners may be one or more thumb screws and one or more threaded inserts. The one or more fasteners may be a plurality of disc-shaped magnets. The at least one recessed attachment pad may further comprise one or more central mounting slots located at a forward end of the at least one recessed attachment pad.
BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of this disclosure, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
Autonomous Trap Magazine
FIG. 1 depicts a perspective view taken from the user's right side of a portable autonomous clay target trap as reflected in the prior art;
FIG. 2A depicts a top down perspective view of the bottom of a hopper as reflected in the prior art;
FIG. 2B depicts a top down perspective view of the top of the plurality of guide tubes as reflected in the prior art;
FIG. 3 depicts a top down perspective view of a magazine according to an embodiment of the present disclosure;
FIG. 4 depicts a top down perspective view of a bottom plate according to an embodiment of the present disclosure;
FIG. 5 depicts a top view of a bottom plate according to an embodiment of the present disclosure;
FIG. 6 depicts a bottom up perspective view of a bottom plate according to an embodiment of the present disclosure;
FIG. 7 depicts a top down perspective view of a temporary stop-block according to an embodiment of the present disclosure; and
FIG. 8 depicts a top view showing the orientation of a temporary stop-block according to an embodiment of the present disclosure.
Weathercocking Arrowhead
FIG. 9A depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 9B depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 10A depicts a right side view of a prior art broadhead arrowhead;
FIG. 10B depicts a right side view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10C depicts a front view of a prior art broadhead arrowhead;
FIG. 10D depicts a front view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10E depicts a left side cutaway view of a prior art broadhead arrowhead;
FIG. 10F depicts a left side cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10G depicts a left side cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10H depicts a left side cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10I depicts a left side view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10J depicts a front view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 10K depicts a left side view of a broadhead arrowhead blade according to an embodiment of the present disclosure;
FIG. 10L depicts a front cutaway view of a broadhead arrowhead blade according to an embodiment of the present disclosure;
FIG. 10M depicts a left side view of a broadhead arrowhead blade according to an embodiment of the present disclosure;
FIG. 10N depicts a bottom cutaway view of a broadhead arrowhead blade according to an embodiment of the present disclosure;
FIG. 10O depicts a left side view of a broadhead arrowhead blade according to an embodiment of the present disclosure; and
FIG. 10P presents a bottom cutaway view of a broadhead arrowhead blade according to an embodiment of the present disclosure.
Smoothbore Shotgun Slug
FIG. 11 depicts a front perspective view taken from the user's right side of a slug designed to be launched from a smoothbore shotgun barrel according to an embodiment of the present disclosure;
FIG. 12 depicts a side view of a slug body shown as a component in a side section view of a cylindrical shotgun shell in the assembled state according to an embodiment of the present disclosure;
FIG. 13 depicts a side section view of a slug body showing one embodiment of the present disclosure;
FIG. 14 depicts a side section view of a slug body showing another embodiment of the present disclosure;
FIG. 15 depicts a side section view of a slug body showing another embodiment of the present disclosure;
FIG. 16 depicts a front perspective view of a slug body showing another embodiment of the present disclosure; and
FIG. 17 depicts a side section view of a slug body showing the right and left halves of the fully split obturator seal with a ramped interface between the obturator seal and the slug body according to an embodiment of the present disclosure.
Quick-Detachable Multi-Purpose Accessory Mounting Platform
FIG. 18A depicts a perspective view taken from the user's right side of a multi-purpose accessory mounting platform according to an embodiment of the present disclosure;
FIG. 18B depicts a left perspective view of the platform, showing left-side mounting pad and left-side surface according to an embodiment of the present disclosure;
FIG. 19 depicts a front view of the platform according to an embodiment of the present disclosure;
FIG. 20A depicts a right side view of the platform, showing right side accessory mounting pad and right side mounting surface according to an embodiment of the present disclosure;
FIG. 20B depicts a cutaway perspective view showing the orientation of mounting slots according to an embodiment of the present disclosure;
FIG. 20C depicts a cutaway perspective view showing the location and geometry of central mounting slots according to an embodiment of the present disclosure;
FIG. 21A depicts a bottom view showing the orientation of a third mounting pad according to an embodiment of the present disclosure;
FIG. 21B depicts a top view of the mounting platform according to an embodiment of the present disclosure;
FIG. 22 depicts a left side perspective view showing an alternate embodiment of a multi-purpose accessory mounting platform;
FIG. 23 depicts a left side perspective view showing another embodiment of a multi-purpose accessory mounting platform for sporting guns;
FIG. 24 depicts a left side perspective view showing yet another embodiment of a multi-purpose accessory mounting platform for sporting guns;
FIG. 30 depicts a front view of a multi-purpose accessory mounting platform according to an embodiment of the present disclosure; and
FIG. 31 depicts a side view of a multi-purpose accessory mounting platform according to an embodiment of the present disclosure.
Glock Magazine Release Button Removal Tool
FIG. 25 depicts a magazine release button disassembly tool according to an embodiment of the present disclosure;
FIG. 26 depicts a front view of a magazine release button disassembly tool according to an embodiment of the present disclosure;
FIG. 27 depicts a magazine release button disassembly tool according to another embodiment of the present disclosure;
FIG. 28 depicts a front view of a magazine release button disassembly tool according to another embodiment of the present disclosure; and
FIG. 29 depicts a rear view of a magazine release button disassembly tool according to an embodiment of the present disclosure.
FIG. 32 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 33 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 34 depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 35A depicts a left side view of a prior art gun;
FIG. 35B depicts a left side view of a broadhead arrowhead and a prior art gun according to an embodiment of the present disclosure;
FIG. 36 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 37 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 38A depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 38B depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 39 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 40 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 41A depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 41B depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 41C depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 42 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 43 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 44A depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 44B depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 44C depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 45 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 46 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 47 depicts a left side view of components of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 48 depicts a left side partial cutaway view of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 49A depicts an enlarged left side partial cutaway of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 49B depicts an enlarged left side partial cutaway of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 49C depicts an enlarged left side partial cutaway of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 49D depicts an enlarged left side partial cutaway of a broadhead arrowhead according to an embodiment of the present disclosure;
FIG. 50 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead constructed in accordance with embodiments of the present disclosure;
FIG. 51 depicts an exploded perspective view taken from the user's right side of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 52A depicts a left side view of components of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 52B depicts a left side view of components of a weather cocking broadhead arrowhead constructed in accordance with the embodiments of the present disclosure;
FIG. 53A depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead just prior to target impact, whose construction is in accordance with embodiments of the present disclosure;
FIG. 53B depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead during target impact, whose construction is in accordance with embodiments of the present disclosure.
DETAILED DESCRIPTION Weathercocking Arrowhead
Embodiments of the present disclosure may eliminate the destabilizing moment produced by a fixed-blade broadhead arrowhead by connecting a specially designed broadhead arrowhead to the arrow shaft through a multiple degree of freedom joint (flex joint). The flex joint allows the broadhead arrowhead to undergo pitching, yawing, and rolling motion decoupled from the motion of the arrow shaft. In combination with the introduction of the flex joint, an arrowhead according to embodiments of the present disclosure may be designed such that the arrowhead itself may fly with positive stability while freely flexing about the flex joint. When designed according to these two conditions, the arrowhead may continuously align itself with the relative wind (i.e., weathercock), and therefore the arrowhead will not produce a destabilizing moment about the cg of the entire arrow. Thus, the restriction heretofore placed on the fixed-blade broadhead arrowhead can be removed; namely, the broadhead arrowhead blades according to embodiments of the present disclosure can be of relatively large span without affecting flight performance. Further, if the launcher (bow, crossbow, airbow, etc.) is tuned properly to minimize launch disturbances, conventional fletching usually required on the arrow to offset the destabilizing moment normally generated by the nose tip may be reduced significantly or eliminated entirely when a weathercocking arrowhead is employed.
It has been found through experimentation that a key to accurate flight of an arrow equipped with a weathercocking arrowhead is to immobilize the arrowhead body by mechanically aligning the central axis of the arrow shaft and the central axis of the arrowhead body during the initial phase of the launch process. As the launch progresses, when the relative wind produced by the forward motion of the arrow obtains sufficient speed to allow the arrowhead body to align with the relative wind vector, immobilization of the arrowhead body with respect to the arrow shaft was found to be no longer necessary. Furthermore, in some instances such as when impacting targets at high obliquity, a means for immobilizing the arrowhead body with respect to the arrow shaft during the penetration event may be advantageous. Such a need may also occur when penetrating or glancing off bone.
FIG. 9A depicts a perspective view taken from the user's right side of weathercocking broadhead arrowhead 500 constructed in accordance with embodiments of the present disclosure. The arrowhead is attached to a standard arrow shaft 510 which may receive a conventional nock 515 located at the distal end of the shaft.
As shown in FIG. 9B the weathercocking arrowhead's body is flexibly connected by a connector element/socket 585 to the forward end of the arrow shaft 510. The aft end of socket 585 may be externally threaded to mate with internally threaded insert 590 that is rigidly connected to the arrow shaft. The arrowhead body and connector element are adapted to flex through a multi-degree of freedom flex joint (ball 560, socket 585, sleeve 570). The arrowhead body has a plurality of blades 540, and each of the blades extend aft of the flex joint. The arrowhead body includes a central base/nose tip 530 connected to the connector element and one or more blades 540 connected to the nose tip. These broadhead blades can be permanently attached to the nose tip, or can be inserted into grooves in the nose tip and held in a fixed position such as through internally threaded blade-lock collar 580 which may mate with external threads (that may or may not be integral) located on the aft end of the nose tip. The arrowhead body includes ball 560, where said ball may be internally threaded to receive the externally threaded nose tip. The ball may be held in position against socket 585 by sleeve 570 whose forward end may be tapered to loosely contact said ball, and whose aft end may be left internally smooth and adhesively attached to the socket or whose aft end may be internally threaded for mechanical engagement with the socket. The arrowhead body may contact an immobilizer (alignment tube halves 520 and 525) which may be in sliding contact with the arrow shaft.
FIGS. 10A-10F depict a prior art broadhead arrowhead 550 (FIGS. 10A, C & E) and the weathercocking broadhead arrowhead 500 of the current invention (FIGS. 10B, D & F). The in-flight transverse aerodynamic forces acting upon an arrow equipped with a prior art broadhead arrowhead and with conventional fletching 555 are depicted in FIG. 10A. In flight, oscillatory pitching and yawing motion occurs about the cg 552 of the arrow and here the central axis of the arrow is depicted pitched to a non-zero angle of attack α at some instant in time. The transverse aerodynamic force F1 produced by the broadhead arrowhead 550 is multiplied by its distance x1 forward of the cg and therefore produces a moment about the cg which is destabilizing for the arrow. To counteract the destabilizing moment produced by the broadhead arrowhead, the fletching is used to produce a stabilizing moment consisting of transverse aerodynamic force F2 multiplied by distance x2 aft of the cg. For stable accurate flight to occur with a prior-art broadhead arrowhead, the product F2x2 must always be greater than the product F1x1. In contrast, a weathercocking broadhead arrowhead 500 as depicted in FIG. 10B eliminates the existence of a transverse force forward of the cg 502 caused by the arrowhead, since the arrowhead enters free-flight having a equal to zero, and a substantially remains at zero throughout the flight due to the multi-degree of freedom joint with flex joint rotational center 507. The arrow shaft 510 is forced to flex about the multi-degree of freedom joint linking the shaft to the arrowhead, and the moment F3x3 stabilizes the arrow shaft without the need for fletching. Even though not required, fletching may still be utilized in conjunction with the current invention without ill-effect.
FIG. 10C depicts a front view of a prior art broadhead arrowhead and shows the relative circumferential positioning of one or more blades 551 about nose tip 1530 and the circumferential positioning of the fletching 555. The location of the section view (FIG. 10E) which may pass through the center of said nose tip is also indicated. FIG. 10D shows the relative circumferential positioning of one or more blades 540 about nose tip 530 and the axisymmetric geometry of the alignment tube composed of symmetric halves 520 and 525. The location of the section view (FIG. 10F) is also indicated which may pass through the center of said nose tip.
Multiple examples of prior art broadhead arrowheads can be found in open literature. FIG. 10E depicts a left side cutaway view of a common embodiment of a prior art broadhead arrowhead, showing an aft externally threaded end of nose tip 1530 to which internally threaded blade-lock collar 1580 may be mechanically attached. Broadhead blades 551 can be permanently attached to the nose tip or can be inserted into grooves in the nose tip and held in a fixed position via the threaded blade-lock collar. The aft end of nose tip 1530 may be externally threaded to mate with internally threaded insert 1590, which may be rigidly attached to the arrow shaft 1510.
FIG. 10F depicts a left side cutaway view of a weathercocking broadhead arrowhead in a state just prior to launch. Some prior art components shown in FIG. 10E, such as arrow shaft 1510, nose tip 1530, blade-lock collar 1580, and internally threaded insert 1590, may be similar to or the same as arrow shaft 510, nose tip 530, blade-lock collar 580, and threaded insert 590 of an embodiment of the present invention shown in FIG. 10F, which may allow reuse of these prior art components with the present invention. Similarly, prior art nock 1515 of FIG. 10A may be similar or the same as nock 515 of FIG. 10B of the present invention.
During launch, the immobilizer is initially required to align the arrowhead body with the arrow shaft. As shown in FIG. 10G, in the preferred embodiment an alignment tube defines a first surface 532 adapted to contact the shaft and a second surface 535 contacting a portion of the arrowhead body in the pre-launch condition. The alignment tube is removably attached to the arrowhead body and defines a central tubular aperture closely receiving the shaft and the arrowhead body. The alignment tube may have a planar surface 538 oriented perpendicularly to an axis defined by the shaft prior to launch. The alignment tube is adapted to allow passage of the arrow and may fall away from the arrowhead body when an arrow including the arrowhead body is launched. The planar surface 538 may catch the relative wind and may also help move the tube rearward with respect to the broadhead arrowhead and
As shown in FIG. 10H the weathercocking arrowhead is adapted to flex through the multi-degree of freedom flex joint. Each of the blades 540 has a forward edge 565 connected to the central base and an aft edge 568 spaced apart from the aft portions of the other blades to define an aft space 548 aft of the central base. The connector element is received in the aft space. The aft portions of the blades are laterally spaced apart from the connector element. The aft space provides ample clearance for unhindered relative motion between the arrowhead and the arrow shaft to occur while in flight.
Again referring to FIG. 10H, to properly weathercock, the broadhead arrowhead 500 must itself have a net-sum moment about the flex joint that is stabilizing. If the arrowhead obtains a non-zero angle of attack with the relative wind, such a stabilizing moment will quickly force the arrowhead central axis back into alignment with the relative wind and therefore ensure that the arrowhead will always weathercock. To ensure the moment about the flex joint is stabilizing, as opposed to destabilizing, the neutral point 505 of the arrowhead must be aft of the flex joint rotational center 507 which also coincides with the geometric center of ball 560. The neutral point is classically defined (see for example: Introduction to Aeronautics: A Design Perspective, Brandt, S. et al, Ch. 6: Stability and Control p. 206) as that location on an aerodynamic body in flight where the aerodynamic body is neither stable nor unstable; if forced to flex about this location the arrowhead body would remain fixed in attitude at a prescribed angle of attack until perturbed. Conversely, if the neutral point is located in front of the flex joint rotational center the arrowhead body would immediately flex to its mechanical limit after launch and cause the arrow to sharply diverge from its intended flight path. The neutral point location is a function of the blade planform shape (see for example: Calculating the Center of Pressure for a Model Rocket, Barrowman, J., p. 18). Since the neutral point must lay aft of the flex joint rotational center for weathercocking of the arrowhead to occur, it is a design requirement for the weathercocking arrowhead that blades 540 extend aft of the flex joint.
Induced rolling of an arrow about its central axis is common practice in prior art arrows and is achieved by canting the fletching with respect to the relative wind. The purpose of rolling the arrow is to increase accuracy (see for example: Modern Exterior Ballistics, McCoy, R., p.237) by roll-averaging the effects of any asymmetric aerodynamic forces caused, for example, by: oscillatory flexing of the arrow shaft during launch, a geometry asymmetry such as a damaged blade, or a manufactured asymmetry such as lateral offset of the cg 552 (FIG. 9B). Similarly, for the reason of increased accuracy the preferred embodiment of the weather cocking arrowhead allows for rolling motion to be superimposed on the pitching and yawing motion of the arrowhead about the flex joint. FIGS. 10I-10P address various techniques for inducing rolling of the broadhead arrowhead about the flex joint in order to increase accuracy of the arrow. These roll-producing techniques applied to each of the blades of the arrowhead body incorporate designed asymmetry (blade 540 with cant angle δ 547, blade 541 with leading edge bevel 544, blade 542 with bent trailing edge 545, blade 543 with airfoiled surface 546) that may be employed separately or in combination with one another to produce the desired roll rate of the arrowhead. FIG. 10I shows blades 540 at a cant angle δ 547 to the central axis of nose tip 531. FIG. 10J shows the relative circumferential positioning of one or more canted blades 540 about nose tip 531. FIGS. 10K-10P show other embodiments of the weathercocking arrowhead that may produce a rolling moment. These embodiments produce roll via geometry modification to the blades themselves. FIG. 10K shows blade 541, whose leading edge 544 is beveled on one side only as shown in FIG. 10L to produce a rolling moment about the symmetry axis of the broadhead arrowhead. FIG. 10M shows blade 542, whose trailing edge 545 is bent on one side as shown in FIG. 10N to produce a rolling moment about the symmetry axis of the broadhead arrowhead. FIG. 10O shows blade 543, whose surface 546 is airfoiled as shown in FIG. 10P to produce a rolling moment about the symmetry axis of the broadhead arrowhead.
Weathercocking broadhead arrowhead 500 may be designed such that nose tip 530, blades 540, and ball 560 may form a broadhead arrowhead whose neutral point 505 lies aft of the geometric center of ball 560. The ball may be loosely captured in position against socket 585 which may mate with the ball to form a ball-and-socket joint. This joint may allow the broadhead arrowhead to flex freely with respect to arrow shaft 510 and weathercock into the relative wind during flight. The initial position of the broadhead arrowhead relative to arrow shaft 510 may be held fixed and in axial alignment by means of alignment tube halves 520 and 525. As the arrow is launched and begins to accelerate, the relative wind may push against the alignment tube halves, causing the broadhead blades to decouple from the tube and self-align with the oncoming air flow. Relative motion between the arrow and the alignment tube may allow the alignment tube to cleanly separate from the arrow. Once disengaged from the alignment tube, the stabilizing moment produced by the broadhead arrowhead about the flex joint may cause the broadhead arrowhead to remain aligned with the relative wind throughout the flight of the arrow, thus reducing or eliminating the need for fletching. To enhance accuracy, rolling motion superimposed on the yawing and pitching motion of the broadhead arrowhead may be induced through designed asymmetry of the blade elements.
ADDITIONAL DISCLOSURE FIG. 32 depicts a perspective view taken from the user's right side of weathercocking broadhead arrowhead assembly 500. Arrowhead assembly 500 is attached to a standard arrow shaft 510 without fletching 555 or nock 515. An immobilizer/alignment tube assembly 600 defines a central tubular aperture closely receiving the shaft and the arrowhead body. The alignment tube is adapted to allow passage of the arrow. FIG. 33 presents the essential components of the alignment tube assembly 600, which consists of a monolithic tube 605 which is adapted internally to receive elastomeric o-rings 615 at either end. A safety rod 610 is permanently attached to the threaded end of tube 605. FIG. 34 presents a section view of the alignment tube 605, indicating the relative locations of o-rings 615, the safety rod 610, the arrowhead assembly 500, and the arrow shaft 510. As shown in FIG. 34, external forward periphery of tube 605 may be further adapted to closely receive arrowhead body of arrowhead assembly 500 providing desired initial axial alignment of arrowhead body with arrow shaft 510.
As indicated in FIGS. 35A and 35B, immobilizer 600 is designed to threadably attach to the muzzle of a gun barrel 292 to convert the gun 290 (air gun, powder gun, etc.) into an arrow launcher. As such, immobilizer 600 remains with the launcher after passage of the arrow. The length of safety rod 610 permanently attached to the threaded end of the tube 605 ensures that only shortened blanks can be inserted into the chamber of a powder gun 290, eliminating the possibility of chambering a non-blank round when the alignment tube assembly is attached to a powder gun. Similarly, when adapted to an air gun, the safety rod eliminates the possibility of chambering a pellet into the gun. Although tube 605 is shown with external threading to attach to the muzzle of gun 290, it is equally viable that tube 605 could be internally threaded in order to fit externally threaded gun barrels such as those barrels threadably adapted to receive a silencer.
FIG. 36 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead assembly 650 threadably attached to arrow shaft 510 via insert 590. As detailed in FIG. 37, central tube 675 is grooved axially to receive blades 670, and on one end receives nose tip 655, and is externally threaded to receive blade lock collar 680 on the opposing end. These components 655, 670, 675, and 680 form an arrowhead body when combined, and mechanically lock blades 670 and nose tip 655 to central tube 675 upon assembly, without blades 670 intruding into the interior space of central tube 675. Flex Post 660 inserts through central tube 675 and is captured by nose tip 655, and is further adapted on the opposite end to threadably attach to arrow shaft 510 via internally threaded insert 590. Axial alignment between flex post 660 and central tube 675 is accomplished via compressible o-rings 665 which mate in grooves 663 of flex post.
FIGS. 38A and 38B each present a section view of central tube 675 and nose tip 655 of the arrowhead assembly 650, indicating relative locations of the flex post 660 in relation to the central tube 675. FIG. 38A details the position of flex post 660 just prior to launch, while FIG. 38B indicates the position of flex post 660 during flight. As shown in FIG. 34B, o-rings 665 attached to flex post 660 are initially received by mating grooves in central tube 675. O-rings 665 are trapped onto flex post 660 via grooves 665 (FIG. 37), but are in sliding contact with central tube 675. Prior to launch, FIG. 38A, axial alignment between flex post 660 and central tube 675 is ensured through mutual contact with o-rings 665. During launch, relative acceleration between flex post 660 and central tube 675 cause the arrowhead body to move rearward in relationship to flex post 660, and allow contact between the head of flex post 660 and the interior socket of nose tip 655. After launch, throughout flight and target impact, flex post 660 remains in flexing contact with nose tip 655 due to drag acting on the arrowhead body.
Flex post 660, o-rings 665, and o-ring grooves 685 of central tube 675 collectively form an integral internal immobilizer prior to launch, aligning the longitudinal axis of the arrowhead body with the longitudinal axis of the arrow shaft. During launch, flight, and impact, the immobilizer is deactivated. The act of pulling the arrow shaft from the target in a direction opposite of flight returns o-rings 665 into mating grooves 685, and thus returns the arrowhead body into axial alignment with the arrow shaft and re-activates the integral internal immobilizer.
FIG. 39 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead assembly 700 threadably attached to arrow shaft 510 via insert 590. As detailed in FIG. 40, central tube 675 is grooved axially to receive blades 670, and on one end receives extended nose tip 705, and is externally threaded to receive blade lock collar 680 on the opposing end. These components 705, 670, 675, and 680 form an arrowhead body when combined, and mechanically lock blades 670 and extended nose tip 705 to central tube 675 without blades 670 intruding into the interior space of central tube 675. Flex Post 660 inserts through central tube 675 and contacts puck socket 715 and socket spring 710, and is captured by extended nose tip 705. Flex post 660 is further adapted on the opposite end to threadably attach to alignment cone 720 and arrow shaft 510 via internally threaded insert 590. Axial alignment between flex post 660 and central tube 675 is accomplished via compressible o-rings 665 which mate in grooves 663 of flex post.
FIGS. 41A-41D each present a section view of central tube 675 and extended nose tip 705 of the arrowhead assembly 700, indicating relative locations of flex post 660 in relation to central tube 675. FIG. 41A details the position of flex post 660 just prior to launch, while FIG. 41B indicates the position of flex post 660 during launch. As shown in FIG. 41B, o-rings 665 attached to flex post 660 are initially received by mating grooves in central tube 675. O-rings 665 are trapped onto flex post 660 via grooves 665 (FIG. 40), but are in sliding contact with central tube 675. Prior to launch, FIG. 41A, axial alignment between flex 660 post and central tube 675 is ensured through mutual contact with o-rings 665. As depicted in FIG. 41B, during launch relative acceleration between flex post 660 and central tube 675 causes the arrowhead body to move rearward relative to flex post 660 and puck socket 715. This relative rearward motion of the arrowhead body forces socket spring 710 to compress until the end of central tube 675 contacts alignment cone 720, which rigidly aligns the arrowhead body with the arrow shaft 510.
When in flight and after launch, as depicted in FIG. 41C, socket spring 710 extends until the sum total of the aerodynamic drag force equals the compressive force of the spring, allowing for central tube 675 to decouple from alignment cone 720 and allowing for weathercocking motion of the arrowhead body to commence. In another similar embodiment not shown, the limited travel of a shorter socket spring may replace socket spring 710 in order to tailor the decoupling behavior of central tube 675 from alignment cone 720 while ensuring weathercocking of the arrowhead body during flight.
FIG. 41D depicts the relative position of central tube 675 relative to flex post 720 at impact. During impact central tube 675 is again forced rearward into contact with alignment cone 720 and the longitudinal axes of the arrowhead body and arrow shaft are again locked into alignment as they were during launch (FIG. 41B).
Flex post 660, o-rings 665, and o-ring grooves 685 of central tube 675 collectively form an integral internal immobilizer prior to launch, initially aligning the longitudinal axis of the arrowhead body with the longitudinal axis of the arrow shaft. The inclusion of puck socket 715, socket spring 710, and alignment cone 720 further provide rigid axial alignment of the arrowhead body with the arrow shaft during launch and at impact, while still allowing for weathercocking of the arrowhead body during flight. Additionally, the act of pulling the arrow shaft from the target in a direction opposite of flight returns o-rings 665 into mating grooves 685, and thus returns the arrowhead body into axial alignment with the arrow shaft and re-activates the integral internal immobilizer.
FIG. 42 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead assembly 750 threadably attached to arrow shaft 510 via insert 590. As detailed in FIG. 43, modified central tube 775 is grooved axially to receive blades 670, and on one end receives nose tip 655, and externally threaded to receive blade lock collar 680 on the opposing end. These components 655, 670, 775, and 680 form an arrowhead body when combined and mechanically lock blades 670 and nose tip 655 to modified central tube 775 upon assembly without blades 670 intruding into the interior space of modified central tube 775. Modified flex post 760 inserts through central tube 775 and is captured by nose tip 655, and is further adapted on the opposite end to threadably attach to arrow shaft 510 via internally threaded insert 590. In this embodiment, axial alignment between modified flex post 760 and central tube 775 is accomplished via a sliding block immobilizer 780, block spring 785, and retaining magnet 790 located on modified flex post 760 between modified central tube 775 and insert 590. Modified flex post 760 and modified central tube 775 are designed in this embodiment such that the use of o-rings to aid in initial alignment of the arrowhead body and the arrow shaft 510 is not required, as no relative sliding motion occurs between modified flex post 760 and modified central tube 775. Furthermore, modified flex post 760 may employ a threaded ball 560 of arrowhead assembly 500 (FIG. 9B) to aid in ease of manufacturing and assembly of this component without loss of fidelity.
FIGS. 44A-44C each present a section view of modified central tube 775, nose tip 655, and sliding block immobilizer 780 of arrowhead assembly 750 (FIG. 42), indicating relative locations of sliding block immobilizer 780 compared to modified central tube 775. FIG. 44A indicated the pre-launch condition of arrowhead assembly 750. In this condition, block spring 785 is extended, driving sliding block immobilizer 780 into the open end of modified central tube 775 and aligning the longitudinal axes of the arrowhead body with the arrow shaft. FIG. 44B indicates the position of the sliding block immobilizer both during launch and in flight. In this figure, the launch acceleration has collapsed the block spring 785, causing the sliding block immobilizer to contact the retaining magnet 790 which itself is held in position against insert 590 by modified flex post 760. The attraction force between the retaining magnet 790 and the sliding block immobilizer 780 has overcome the tension of the compressed block spring 785, and the immobilizer is held fixed by the magnet, allowing the arrowhead body to weathercock in flight. FIG. 44c indicates the position of the sliding block immobilizer 780 after target impact. Here the impact deceleration of the arrow forces sliding block immobilizer 780 to be released from retaining magnet 790, allowing block spring 785 to drive the sliding block immobilizer 780 forward again into the open end of the modified central tube 775, locking the arrowhead body into axial alignment with the arrow shaft 510 as the penetration event proceeds to completion. After the penetration event, the sliding block immobilizer 780 does not require resetting, as it has returned to the initial launch condition shown in FIG. 44A during target penetration.
FIG. 45 depicts a perspective view taken from the user's right side of a relatively large weathercocking broadhead arrowhead assembly 800. As detailed in FIG. 46, tubular insert 845 threadably receives set screw 847, and is attached to arrow shaft 510 with adhesive as is standard practice in the field of archery. The opposing end of tubular insert 845 is adapted to closely receive puck magnet 830, insert spring 835, a second puck magnet 830 followed by tubular insert cap 825 which is forcibly pressed into place within tubular insert 845 and held in place by friction. Insert cap 825 is adapted to closely receive flex post magnet 820. The length of insert spring 835 can be manually adjusted via set screw 847. Steel ball 815 is forcibly pressed into arrowhead 805 such that arrowhead 805 can be mounted to the arrow shaft through the magnetic attraction naturally occurring between flex post magnet 820 and steel ball 815. Immobilizer/external o-ring 840 is closely received by the outer exposed diameter of tubular insert 845, and is held in place during flight and impact by o-ring groove 842. Blade weight 810 is attached to one blade of the cruciform four blade arrowhead 805, forcing this blade to align vertically due to gravity before an arrow equipped with arrowhead assembly 800 (FIG. 45) is launched. The action of the blade weight in aligning one blade vertically also forces two diametrically opposed blades of cruciform arrowhead 805 to align horizontally before launch. Such a configuration is useful when hunting large game bird species such as duck, geese, or turkey where the neck of the game bird is to be severed.
FIG. 47 details a unique aspect of the magnetic attraction between steel ball 815 and flex post magnet 820 whose poles are located at the distal ends of the magnet. Even though the end faces of flex post magnet 820 are flat, steel ball 815 remains centered on the face of the magnet, and when displaced laterally, steel ball 815 automatically returns to the center of the end face of the magnet. Thus, the magnetic attraction between flex post magnet 820 and steel ball 815 form a virtual ball and socket joint when combined as described in this embodiment. A second feature of the magnetic coupling between steel ball 815 and flex post magnet 820 is that the joint formed is relatively weak, and therefore if an arrow equipped with relatively large broadhead misses the intended target and strikes an immoveable object, arrowhead 805 will detach from arrow shaft 510, absorbing impact energy and greatly reducing or eliminating damage occurring to these components.
FIG. 48 depicts a left side partial cutaway view of a broadhead arrowhead according to the embodiment of the present disclosure described in FIG. 47. For convenience, details of the interaction of the components during pre-launch, launch, flight, and impact phases are presented in FIGS. 49A-49D, respectively. In the pre-launch condition detailed in FIG. 49A, external immobilizer o-ring 840 is seated against arrowhead 805 and is positioned forward of groove 842. As such o-ring 840 provides an interface between arrowhead 805 and tubular insert 845 which holds the arrowhead body in axial alignment with arrow shaft 510. During launch, as detailed in FIG. 49B, the arrowhead body including steel ball 815 sets back against flex post magnet 820, which in turn compresses insert spring 835 and allows o-ring 840 to move rearward and seat into o-ring groove 842. During this phase the arrowhead body remains in axial alignment with the arrow shaft. As depicted in FIG. 49C, after launch, insert spring 835 extends flex post magnet 820 forward relative to tubular insert 845, which in turn releases contact between o-ring 840 and arrowhead 805, while o-ring 840 remains in o-ring groove 842. In this condition the arrowhead is free to weathercock in flight. At impact, as shown in FIG. 49D, insert spring 835 is again compressed, allowing arrowhead 805 to move rearward and re-engage o-ring 840, which forcibly aligns the arrowhead with the arrow shaft and locks the components together during the impact event. After impact, immobilizer o-ring 840 must be manually repositioned ahead of o-ring groove 842 before the arrow is launched again.
FIG. 50 depicts a perspective view taken from the user's right side of a weathercocking broadhead arrowhead assembly 850 threadably attached to arrow shaft 510 via insert 590. As detailed in FIG. 51, short central tube 865 on one end is internally threaded to receive nose 860, and also adapted to receive blade lock ring 870 on the opposing end. Blade lock ring 870 in turn interfaces with integral hooks 858 of flat blade 855. Dimple 862 of nose 860 likewise interfaces with integral nipple on flat blade 855. The action of rotating short central tube 865 with respect to flat blade 855 expands nose 860 relative to lock ring 870 and results in locking components 855, 860, 865, and 870 together to form a two blade broadhead arrowhead body with an open central aperture within short central base 865. Extended flex post 880 inserts through short central tube 865 and is captured by nose 860, and is further adapted on the opposite end to threadably attach to arrow shaft 510 via internally threaded insert 590. Axial alignment between flex post 660 and short central tube 865 is accomplished via compressible o-rings 665 which mate in grooves 885 of extended flex post 880. External immobilizer/flexible insert 875 is bonded or otherwise physically attached to flat blade 855 prior to assembly.
FIGS. 52A and 52B each present a section view of short central tube 865, lock ring 870, and nose 860 of arrowhead assembly 850 (FIG. 50), indicating relative locations of extended flex post 880 in relation to short central tube 865. For clarity, external immobilizer/flexible insert 875 is not shown in
FIG. 52A or FIG. 52B. FIG. 52A details the position of extended flex post 880 just prior to launch, while FIG. 52B indicates the position of extended flex post 880 during flight and impact. As shown in FIG. 52B, o-rings 665 attached to extended flex post 880 are initially received by mating grooves in short central tube 865. 0-rings 665 are trapped onto extended flex post 880 via grooves 885 (FIG. 51), but are in sliding contact with short central tube 865. Prior to launch, FIG. 52A, axial alignment between extended flex post 880 and short central tube 865 is ensured through mutual contact with o-rings 665. During launch, relative acceleration between extended flex post 880 and short central tube 865 cause the arrowhead body to move rearward in relationship to extended flex post 880, and allow contact between the head of flex post 880 and the interior socket of nose 860. After launch, throughout flight, and at target impact, extended flex post 880 remains in flexing contact with nose 860 due to drag acting on the arrowhead body.
Extended flex post 880, o-rings 665, and o-ring grooves 890 of short central tube 865 collectively form an integral internal immobilizer prior to launch, aligning the longitudinal axis of the arrowhead body with the longitudinal axis of the arrow shaft. During launch, flight, and impact, the integral internal immobilizer is deactivated. The act of pulling the arrow shaft from the target in a direction opposite of flight returns o-rings 665 into mating grooves 890, and thus returns the arrowhead body into axial alignment with the arrow shaft and re-activates the integral internal immobilizer.
Immobilizer/flexible insert 875 shown in FIG. 51, FIG. 53A and FIG. 53B serves several purposes. As shown in FIG. 51, flexible insert 875 serves to fill in the open area present in flat blade 855. In some states, fixed blade broadheads with an open interior area are considered to have barbed blades, and are illegal for hunting. A second purpose of flexible insert 875 is to provide a means for inducing spin. The “S” shaped cross section of flexible insert 875 allows for a pressure differential to occur on opposite sides of the insert. Therefore, as the spin inducing mechanism is inherent in insert 875, and not in flat blade 855, ease of manufacturability of the broadhead is increased as the blade can be cut from sheet stock, while insert 875 can be injection molded or 3D printed with ease. A final purpose served by the immobilizer/flexible insert 875 is detailed in FIGS. 53A and 53B. FIG. 53A shows weathercocking broadhead assembly 850 just prior to impact with pre-impacted target 895. At this point in the flight, the integral internal immobilizer is deactivated as described previously. However, as FIG. 53B indicates, during the penetration event, immobilizer/flexible insert 875 collapses in to a double S shaped curve depicted as collapsed insert 876 due to interaction with the impacted target 896. The collapsed insert 876 collapses onto and traps extended flex post 880, and thus immobilizes the arrowhead body with respect to the arrow shaft 510. A further benefit of collapsed insert 876 is that interaction of the insert and the penetration cavity is minimized when the insert is in the collapsed condition.
Embodiments of the present disclosure may utilize commercially available arrow shafts, nocks, and shaft inserts, and nose tips. Conventional metals, urethanes, and plastics can be utilized for each component, and machining practices such as lathe work, water jet cutting, milling, injection molding and 3D printing may be incorporated in manufacturing a weathercocking arrowhead according to embodiments of the present disclosure.
