Abstract
An expandable broadhead includes a number of fixed blades cumulating in a point, with each of the fixed blades having a channel for receiving a cammable deployable expansion blade, with the expansion blade having a slot which cooperates with a fixed retaining pin transverse to the channel that cams the deployable blade outwardly when a forward impact shoulder of the deployable blade strikes a target. This moves the blade relative to the fixed retaining pin and thus cams the deployable blade out to an expanded position for maximum blade cutting edge contact to effectuate maximum damage to the target and a quick kill.
Claims
1. An expandable broadhead, comprising: a plurality of fixed blades; a plurality of retaining pins; and a plurality of rear-deploying blades; wherein: each of the plurality of retaining pins is inserted into a respective fixed blade; each of the plurality of rear-deploying blades is mounted on a respective retaining pin; and each of the plurality of rear-deploying blades comprises a slot configured to translate and rotate on a respective retaining pin.
2. The expandable broadhead of claim 1, wherein the plurality of fixed blades meet at a tip of the expandable broadhead.
3. The expandable broadhead of claim 1, wherein each of the plurality of fixed blades comprises a channel configured to house a rear-deploying blade.
4. The expandable broadhead of claim 1, wherein each of the plurality of retaining pins comprises a threaded end portion and an unthreaded central portion.
5. The expandable broadhead of claim 1, wherein the plurality of fixed blades comprises three fixed blades, the plurality of retaining pins comprises three retaining pins, and the plurality of rear-deploying blades comprises three rear-deploying blades.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) These and other features of the subject invention will be better understood in connection with the Detailed Description, in conjunction with the Drawings, of which:
(2) FIG. 1 is a diagrammatic illustration of a broadhead having a deployable blade mounted to a fixed blade through a retaining pin that extends through a channel in the fixed blade, indicating an impact force delivered to a forward shoulder on the deployable blade resulting in the swinging of the deployable blade away from the broadhead center line upon delivery of an impact force;
(3) FIGS. 2A-2F illustrate the operation of the broadhead of FIG. 1 prior to impact and during impact at which point the forward shoulder moves the deployable blade aft so that it rotates and translates on a fixed retaining pin to cam the deployable blade from an inflight position to an extended position;
(4) FIG. 3 is a diagrammatic illustration of the broadhead of FIG. 1 illustrating the attachment of the broadhead ferrule screwed into an end of an arrow, also illustrating a shock collar having a camming surface and a frangible tab which breaks upon impact allowing the deployment of the rotatable and translatable blade after impact;
(5) FIG. 4 is a side view of the ferrule and fixed blades of the broadhead of FIG. 3 illustrating the channels in the fixed blade into which are disposed the deployable blades;
(6) FIG. 5 is an isometric view of the broadhead of FIG. 1 illustrating the capture of the deployable blades in a channel in the fixed blade, also illustrating the needle like point of the broadhead which is supported on at least three sides by the three fixed blades which culminate in the point;
(7) FIG. 6 is a diagrammatic illustration of the broadhead of FIG. 5 illustrating the swinging out of the deployable blades upon impact with a target;
(8) FIG. 7 is an isometric view of the broadhead of FIG. 1 illustrating the deployable blade position in flight, or prior to extension;
(9) FIG. 8 is a front view of the broadhead of FIG. 7 illustrating the inflight position of the deployable blades with edges facing outward from the centerline of the broadhead;
(10) FIG. 9 is an isometric view of the broadhead of FIG. 7 showing the position of the deployable blades extended after target impact;
(11) FIG. 10 is a front view of the broadhead of FIG. 9 showing a front view of the extension of the deployable blades, also illustrating the clearance between the blades due to the offset of the fixed retaining pins from the ferrule center axis;
(12) FIG. 11 is an exploded view of the broadhead of FIG. 1 illustrating the fixed blades attached to a central ferrule, deployable blades to be assembled into channels within the fixed blades, retaining pins that retain the deployable blades in the fixed blade channels by the insertion of the pins through channels in the fixed blades, also showing a shock collar and a specialty washer having camming surfaces adapted to coact with rear cam following surfaces of the deployable blades;
(13) FIG. 12 is a diagrammatic illustration of the broadhead assembled in accordance with the exploded view of FIG. 11 illustrating the shock collar and specialty washer in place on the ferrule, also illustrating the positioning of a frangible protruding tab on the shock collar and the camming surface of the specialty washer adjacent an associated deployable blade;
(14) FIG. 13 is a diagrammatic illustration of the specialty washer of FIG. 11;
(15) FIGS. 14A, 14B and 14C are various isometric views of the shock collar of FIG. 11;
(16) FIG. 15 is a diagrammatic illustration of a fixed retaining pin for use in the broadhead of FIG. 1;
(17) FIG. 16 is a cross sectional view of a broadhead utilizing the fixed retaining pin of FIG. 15 that transverses a channel in the fixed blade of the broadhead, illustrating threaded ends and an unthreaded central shank portion of the fixed retaining pin; and,
(18) FIG. 17 is a diagrammatic illustration of an alternative embodiment of the fixed retaining pin of FIG. 15.
DETAILED DESCRIPTION
(19) Referring now to FIG. 1, a broadhead 10 includes a number of fixed blades 12 each having a groove or channel 14 adapted to receive a movable deployable or auxiliary blade 16 therein. Each of the deployable blades has a longitudinally running slot 18, with a fixed retaining pin 20 utilized to retain the deployable blade in the associated channel of the fixed blade.
(20) In operation, an impact force 22 impacts a forward impact shoulder 24 to move the deployable blade aft such that the relative position of the associated slot and the fixed retaining pin changes as the deployable blade moves aft. The result is that the deployable blade swing out to an expanded position as illustrated by expansion arrow 26 from an inflight position to an extended position due to the rotation and translation of slot 18 about fixed retaining pin 20.
(21) In this view a shock collar 30 is utilized to strengthen the ferrule and absorb broadhead impact, with the deployable blades being locked in position due to a frangible tab 32 that coacts with a notch 34 in the aft portion of the deployable blade. When the deployable blade is moved aft this tab snaps off allowing the deployable blade to swing outward as illustrated by arrow 26 due to the rotation and translation deployable blade slot 18 about fixed retaining pin 20 that provides the primary camming action for extending the deployable blade upon exertion of impact force 22.
(22) Additionally a specialty washer 33 has a camming surface 36 which coacts with a cam following surface 38 on the rear portion of deployable blade 16 that under certain circumstances further swings the deployable blade outwardly upon the aft motion of the deployable blade during impact. While in certain circumstances camming surface 36 may not engage cam following surface 38, often times in high impact situations the deployable blade will be moved fully aft and engage camming surface 36 on specialty washer 33.
(23) Note that in the manufacturing of the ferrule a longitudinally camming rib positioned between fixed blades 12 serves to reinforce a needle-like tip 60 to prevent tip damage during target penetration. Thus the fixed blades that culminate in the tip and the reinforcing ribs permit an exceptionally sharp needle-like tips to be provided, capable of improved target penetration.
(24) Referring to FIGS. 2A-2F, the operation of the subject broadhead is illustrated. As illustrated in FIG. 2A broadhead 10 is shown with deployable blades 16 in their inflight positions prior to broadhead 10 striking target 40.
(25) As illustrated in FIG. 2B as the broadhead 10 impacts target 40 forward shoulder 24 is moved aft to begin to swing deployable blade 16 outwardly due to the coaction of slot 18 which serves as a cam follower on the camming surface provided by retaining pin 20.
(26) Referring to FIG. 2C, as the broadhead 10 moves in to further pierce target 40 the rear movement of deployable blade 16 is shown by arrow 42 which causes the distance 44 between the front end 46 of slot 18 and retaining pin 20 to decrease, with the retaining pin effectively moving towards forward shoulder 24 when viewed from the position of slot 18. Alternatively this action can be described by the movement of the deployable blade in the direction of arrow 42 which exposes more of the distal end 48 of slot 18 during broadhead penetration.
(27) As can be seen from FIG. 2D the space between fixed retaining pin 20 and the front end 46 of slot 18 decreases as illustrated by double ended arrow 50 as the deployable blades 16 move in the direction of arrow 26 from the inflight position to the extended position, with the relative position of fixed retaining pin 20 and front slot end 46 decreasing. This causes the rotation and translation of the deployable blades outwardly so that they swing into their fully extended position.
(28) Referring to FIG. 2E, the fully extended position of deployable blade 16 is shown such that the fixed retaining pin 20 has now rests on the front end 46 of slot 18 leaving the exposed position of slot 18 as illustrated.
(29) Finally as illustrated at FIG. 2F, broadhead 10 is shown having penetrated target 40 with the outer edges 52 of deployable blades 16 cutting into target 40.
(30) Referring now to FIG. 3, broadhead 10 is shown having fixed blades 12 culminating into a needle sharp tip 60 which is supported by the adjacent fixed blade surfaces 62 such that the tip does not crumple when impacting a target.
(31) This provides the broadhead with increased penetrating power due to the needle-like tip. Here it can be seen that deployable blades 16 reside in channels or grooves 14 in the associated fixed blade. While there could obviously be other workable combinations of blade width and slot clearance, the preferred embodiment has a groove or channel 14 made sufficiently wide such that with a fixed blade width of 0.035 and a channel width of 0.039 provide sufficient clearance to prevent jamming
(32) Also shown in FIG. 3 is shock collar 30 that is utilized to absorb blade slap during impact the deployable blades are maintained in position during flight through the utilization of the frangible tab 32 in notch 34. Also shown is the cam following surface 38 which is adapted to cam on camming surface 36 which is part of a specialty washer 33 that is inserted into the aft end of shock collar 30.
(33) Referring to FIG. 4, channel or groove 14 is shown having a width illustrated by arrows 66, clearly sufficient to provide clearance for the translation and rotation of the deployable blades to be placed therein. Thus the translation and rotation of the deployable blades in the channel or groove is not constrained such that the blades will not jam during deployment.
(34) Referring to FIG. 5, here it can be seen in the inflight condition that deployable blades 16 are locked into position by frangible tab 32 on shock collar 30, with the camming surface 36 adjacent cam follower 38.
(35) Referring to FIG. 6, upon extension of deployable blades 16 the frangible tab 32 has been sheared off such that it no longer exists in notch 34 in deployable blade 16. Here in the partial deployment of blade 16 the camming surface 36 is not in contact with cam follower 38 as the deployable blade 16 has not moved aft sufficiently for this contact.
(36) Referring to FIG. 7, another view of the broadhead 10 is shown in which deployable blades 16 are shown in their inflight position and locked in place by tabs 32 in notches 34 in the deployable blades. Here it can be seen that camming surface 36 is about to contact cam follower 38 during the expansion of deployable blades 16.
(37) Referring to FIG. 8, from a front view during the inflight position of broadhead 10 deployable blades 16 are arranged separated by 120 degrees, with the cutting edges 52 facing front and with the cutting edges 70 of the fixed blades also facing front.
(38) Referring now to FIG. 9, the fully extended deployable blades 16 are shown with their cutting edges 52 facing front as are the cutting edges 70 of fixed blades 12.
(39) Referring to FIG. 10, from a front point of view the fully extended position of deployable blade 16 is shown with considerable distance between the front shoulder 24 of blade 16 with respect to any portion of blade 16. This clearance is important such that upon deployment the blades do not interfere with one another. The reason for the non-interference has to do with the distance between fixed retaining pin 20 and the center line 74 on which ferrule tip lies. This offset distance illustrated by arrow 80 is what accounts for the clearances between the deployable blades. In one embodiment the distance 80 is 0.328 inches. Note that in one embodiment the distance from front shoulder 24 and the centerline of pin 20 is 0.283, whereas the distance from the centerline of pin 20 and the distal end of blade 16 is 0.290.
(40) Referring now to FIG. 11, how broadhead 10 is constructed can be seen in this exploded diagram in which deployable blades 16 are to be positioned in grooves or channels 14 in fixed blades 12 that cumulate in point 60. Here it can be seen that the deployable 16 are captured in the respective grooves or channels 14 utilizing a fixed retaining pin or fastener 20 which in one embodiment passes through an orifice 82 in fixed blade 12 and through slot 18 in the corresponding deployable blade.
(41) Here it can be seen that shock collar 30 is mounted to broadhead 12 along a central ferrule portion 84, with specialty washer 33 mounted into receiving slots 86 in shock collar 30. It will be noted that specialty washer 33 provides hard camming surfaces 36 which are to communicate with cam followers 38 on the aft portion of associated deployable blades 16, with the shock collar being secured against rotation about ferrule portion 84 in a tongue and groove structure illustrated by grooves 88 on the ferrule. Note also that frangible tabs 32 are integrally formed in shock collar 30.
(42) Referring to FIG. 12, it can be seen that shock collar 30 is in place on ferrule portion 84 such that frangible tab 32 is within notch 34 on deployable blade 16. Here it can clearly be seen that specialty washer 33 has camming surfaces 36 in respective grooves on the shock collar that in turn communicate with cam followers 38 on the aft portion of deployable blades 16.
(43) Referring to FIG. 13, specialty washer 33 is shown having camming surfaces 36 clearly indicated around the periphery of the specialty washer.
(44) Referring to FIGS. 14A, 14B and 14C shock collar 30 is provided with frangible tabs 32 around its periphery, also showing grooves 86 adapted to receive camming surfaces 36 therein when specialty washer 33 is inserted into the aft end of the shock collar.
(45) As shown in 14C an internal rib 90 is utilized as a key to prevent rotation of the shock collar on ferrule portion 84 due to its cooperation with slots 88 of FIG. 11.
(46) Referring now to FIG. 15, in one embodiment fixed retaining pin 20 has threaded end portions 92 and 94 and a central unthreaded portion 96.
(47) Referring to FIG. 16, when retaining pin 20 is screwed into groove or channel 14 in fixed blade 12, slot 18 in deployable blade 16 rides on the unthreaded portion 96 of fixed retaining pin 20.
(48) Thus the extension of the deployable blade as it rotates and translates on fixed retaining pin 20 does not come into contact with any threaded portion of the fixed retaining pin. As a result it is possible to remove and replace the deployable blades by simply unscrewing the fixed retaining pin since its movement out of channel 14 in fixed blade 12 is not impeded by shards of metal that may be removed from threads on the pin during blade slap should the pin be fully threaded during the impact slap when the broadhead impacts the target.
(49) Referring now to FIG. 17, an alternative embodiment of retaining pin 20 is shown with a threaded end portion 100 and an unthreaded central portion 102 adjacent a retaining pin head 104. It will be appreciated that the unthreaded portion 102 resides in the channel or slot in the fixed blade such that, as in the prior embodiment, the slapping of the auxiliary blade during extension does not result in shavings or filings in the threaded portion. Thus this retaining pin and blade are also easy to remove to allow replacement of the auxiliary blades.
(50) As to the materials of the broadhead first and foremost the fixed blade is preferably made of any number of grades of steel, stainless steel or titanium with example grades of 12L14 steel, 4140 steel, 420 stainless steel, Ti6Al4V titanium, or grade 2 titanium whereas the deployable blades are preferably made of a martensitic grade of stainless steel such as 420 or 440 stainless. The shock collar is made of shock absorbing material nylon, polypropylene, glass filled nylon, polycarbonate, aluminum, zinc or ceramic such as Al2O3 with the material also providing that the tabs returned in making notches are frangible whereas the specialty washer which contains the camming surfaces is made of a hard and tough material such as austenitic grades of stainless steel such as 301 or 304 stainless, or martensitic stainless steel such as 420 or 440 stainless, or steel grades such as 4340 or 4140.
(51) While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications or additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims.
