This invention generally relates to a projectile weapon, and more particularly to an arrow with aligning features for the nock and/or the head.
In general, it is known to construct an arrow 10 to include a shaft 12, a head 14 attached to or positioned at a front of the shaft 12, fletchings 16 positioned near a rear end of the shaft 12, and a nock 18 on the rear end of the shaft 12, as illustrated in
Normally, the shaft 12 is round in cross-section. The head 14 may attach thereto and may be configured to strike or pierce a target upon the arrow 10 being fired from a projectile firing device, such as a bow or a crossbow (not pictured). Connection between the head 14 and the shaft is normally accomplished by inserting at least a portion of the head within an aperture, receiver, or otherwise hollow portion of the shaft 12. The connection may be a friction fit, may be threaded, or may include the use of an adhesive.
The arrow 10 may include three fletchings 16, which may be positioned equidistantly around a circumference of the shaft 12. The fletchings 16 are adapted to act as airfoils and stabilize the arrow during flight. The nock 18 may attach to the shaft 12 and may include a bowstring receiver (such as in the form of a notch or groove) for aligning the bowstring with the arrow in order to initiate flight. Connection between the nock 18 and the shaft 12 is normally accomplished via insertion of at least a portion of the nock 18 into the shaft 12. As with the head, the connection between the nock 18 and the shaft 12 may be a friction fit, may be threaded, or may include the use of an adhesive.
Alignment between the nock 18 and the shaft 12 is important, as this alignment is responsible for the relative position of the arrow 10 and the bow when the arrow is shot. If the nock is not properly aligned, then one or more fletchings 16 may contact the bow as the arrow is released, thereby affecting the trajectory and/or speed of the arrow during flight.
Similarly, alignment of the head 14 with the shaft 12 may be important, especially in the case of broadhead, which may include three blades. Specifically, alignment of the blades of the broadhead with the fletchings 16 may lend to a straight trajectory during flight.
Current methods of alignment between the nock and the shaft and/or between the head and the shaft include a simple visual inspection of alignment, or may include some form of a reference point for alignment. For instance, the shaft 12 and/or the nock 18 or head 14 may include a marking or a ridge for indicating an appropriate alignment configuration. However, these manual alignment methods are prone to user error in alignment, and allow for twisting, turning, and working loose of the nock and/or head through normal use.
Accordingly, a need has been identified for an arrow with an improved alignment system which addresses these and other shortcomings of traditional arrows.
In one embodiment, the present invention generally relates to an arrow with self-aligning features comprising a shaft including a rounded polygonal cross-section and a removable nock including a cross-section matching the rounded polygonal cross-section of the shaft and adapted to engage the shaft along the rounded polygonal cross-section, thereby preventing relative rotation therebetween.
In one aspect, the rounded polygonal cross-section may comprise a reuleaux triangle. The shaft may include an aperture in the shape of a reuleaux triangle, and the nock may include a projection in the shape of a reuleaux triangle adapted for insertion into the aperture.
The arrow may further include a plurality of fletchings attached to the shaft, each of the fletchings positioned at a midpoint between two corners of the rounded polygonal cross-section.
The rounded polygonal cross-section may extend over various lengths of the shaft. For example, it may extend along an entire length of the shaft. Alternately, the cross-section may extend only along an end of the shaft adjacent the engagement of the nock.
In one aspect, the rounded polygonal cross-section may extend along at least a portion of the shaft opposite an end of the shaft adjacent the engagement of the nock. The arrow may further include a head comprising a cross-section matching the rounded polygonal cross-section of the shaft and adapted to engage the portion of the shaft opposite the end of the shaft adjacent the engagement of the nock.
In another aspect, the arrow may include a connector for connecting a head to the shaft, wherein the connector comprises a cross-section matching the rounded polygonal cross-section of the shaft and adapted to engage the portion of the shaft opposite the end of the shaft adjacent the engagement of the nock. The connector may comprise an aperture for engaging the head. In another aspect, the connector may comprise a projection for engaging the head. The connector may include one or more fasteners adapted to lock the head in position relative to the shaft.
In a further embodiment, an arrow with self-aligning features includes a shaft with a first end and a second end, said shaft including a first aperture at the first end and a second aperture at the second end, wherein the first aperture and the second aperture each comprise a reuleaux triangular shape, and a removable nock including a first extension with a reuleaux triangular cross-sectional shape, wherein the first aperture is adapted to receive the first extension, thereby preventing relative rotational movement between the shaft and the nock.
The arrow may further include a head comprising a second extension with a reuleaux triangular cross-sectional shape, wherein the second aperture is adapted to receive the second extension, thereby preventing relative rotational movement between the shaft and the head.
In one aspect, the arrow may further include a connector with a reuleaux triangular cross-sectional shape, wherein the second aperture is adapted to receive the connector, thereby preventing relative rotational movement between the shaft and the connector. The arrow may further include a head adapted to engage the connector, wherein the connector includes a receiver adapted to receive at least a portion of the head, and a fastener adapted to lock the head in position with respect to the connector.
In another aspect, the arrow may further include a head adapted to engage the connector, said head including a receiver and a fastener, wherein the connector includes a second extension, and wherein the receiver is adapted to receive the second extension, and wherein the fastener is adapted to lock the head in position with respect to the connector.
In a further embodiment of the present invention, an arrow with self-aligning features for use with an archery weapon including a string is disclosed. The arrow may comprise a shaft including an end with a reuleaux triangular cross-section, a plurality of fletchings attached to the shaft, at least one of said fletchings comprising an index vane, and a removable nock including a cross-section matching the reuleaux triangular cross-section of the shaft and adapted to engage the shaft along the reuleaux triangular cross-section of the shaft and the nock, and the nock further including a notch adapted to engage the string along a longitudinal length of the notch, wherein engagement of the shaft and the nock establishes a fixed relative angular position between the longitudinal length of the notch and the index vane. In one aspect, the relative angular position between the longitudinal length of the notch and the index vane may be 90 degrees. Alternately, the relative angular position may be zero degrees.
The description provided below and in regard to the figures applies to all embodiments unless noted otherwise, and features common to each embodiment are similarly shown and numbered.
The device of the current invention relates to an arrow 10 including a shaft 112, at least a portion of the length of the shaft including a cross-sectional shape in the form of a rounded polygon. This rounded polygonal cross-section may be in the form of a reuleaux polygon, such as a reuleaux triangle (“RT”). Alternately, the rounded polygonal cross-section may include any number of sides, such as from six to twelve sides. In one aspect, the shaft 112 may be threadless.
As illustrated in
In another aspect, as shown in
As shown in
In each of
A RT cross-sectional shape 120 is illustrated in
The fletchings 116 may be spread around a perimeter of the cross-section of the shaft, spaced equidistantly from one another. In the case of a RT cross-section, the fletchings may be located at 120 degree intervals around the perimeter of the shaft 112. For instance, the fletchings 116 may be attached to the shaft 112 at a midpoint between the rounded corners 124 on each of the rounded sides 122. In another aspect, the fletchings 116 may be located on each of the rounded corners 124. The longitudinal location of the fletchings 116 may be closer to the rear end than the front end of the shaft 112.
A shaft including the RT shape may be significantly stronger than a conventional round shaft of the same size. Specifically, a RT shaft may have a greater static and dynamic spine strength than a round shaft. The flexural rigidity of a RT shaft is also different due to its shape. In the case of a round shaft, the flexural rigidity is generally constant, regardless of the orientation of the arrow. In the case of a RT arrow, with a rounded corner 124 facing up, a RT shaft has a different rigidity (spine strength) with respect to a given force normal to a longitudinal axis of the arrow than with the rounded corner 124 facing down. Multiple spine strengths from one arrow may allow a manufacturer to produce fewer arrows to address the same number of spine strengths desired by a given set of consumers, than is true with arrows with round shafts. Similarly, a single arrow with different flexural rigidity depending on orientation of the arrow (such as with a RT arrow) may give multiple usage options for a given consumer with that single arrow.
Because a RT shaft has a greater flexural rigidity than a round shaft, a RT arrow has less oscillation back and forth when leaving the bow, which will straighten the arrow out faster during flight. This results in a flatter trajectory and straighter arrow at close range targets for a RT arrow than a round shaft arrow. The RT shaft also has greater durability and straightness than a traditional round shaft. Eliminating wobble and/or oscillation also improves accuracy. The added rigidity and strength of a RT shaft may also allow for a thinner wall thickness than a rounded shaft, which would lighten the overall weight of the arrow.
The shaft 112 of the present invention may be parallel/straight, tapered, or barreled along the longitudinal axis. The shaft and arrow may be used in association with a recurve bow, a compound bow, a crossbow, or any other weapon capable of firing an arrow. The shaft may be constructed from a variety of different materials such as aluminum, aluminum alloys, graphite, graphite composites, boron, titanium, carbon, carbon composites and the like or combinations thereof. The various embodiments of the arrow shaft may be formed by cold working in a mandrel drawn process. An extrusion method may also be used. Another process for forming the arrow of the present invention is to use a conventional round arrow and form or attach the RT portion or portions into it. An example would be to take a round aluminum (or other suitable material) arrow and insert at least a portion of the arrow into a press or mold so that the relevant portion may be pressed or formed into the RT shape. Another process for forming the arrow of the present invention is to use a mandrel in the arrow shaft shape (including a RT portion or portions), wrap it with flexible material, and cure the material to form the shaft.
In a further aspect of the present invention, a self-locking and aligning knock 118 is disclosed. As shown in
As shown in
The nock adapter 140 may include a collar 141 about a perimeter of an end of the nock adapter 140 that does not insert into the aperture 130. Upon engagement with the shaft 112, the collar 141 may be at least partially external to the aperture 130. The collar 141 may include a taper outward toward the perimeter of the shaft 112. This outward taper may be adapted to at least partially deflect a second arrow that may be fired at the nock end of a first arrow, such as a first arrow that has already been embedded in a target.
The adapter 140 may include an aperture 142 for receiving an adapter mating nock 118′. The adapter mating nock 118′ may include a projection 132′ such as a male shank or stud for mating with the aperture 142. The projection 132′ and the aperture 142 may both include a similar cross-sectional shape, such as a RT (or other rounded polygon).
In either embodiment of
Proper and fixed alignment of the present invention is different from a conventional round nock (such as a press-in nock) and shaft, which is prone to twisting, turning and loosening over time, even in the presence of an adhesive. Conventional round nock and shaft configurations that are prone to misalignment may result in the arrow fletchings undesirably rubbing a portion of the bow (such as the arrow rest), and may cause an inaccurate flight path. The locked and aligned nock 118 and shaft 112 of the present invention may result in the fletchings 116 (which are fixed to the shaft 112) consistently being positioned in a desirable relative position with the bow string, and therefore a desirable relative position with respect to the bow.
In addition, the present invention may allow for alignment of a head 114 with a shaft 112 and/or fletchings 116 of the arrow. The head 114 may take the form of a point (e.g. a target point, a bullet point, a combo point, a field point, a judo point, a blunt point, or a bludgeon point) or a broadhead. In the case of a point with a RT shape, alignment to match the three rounded sides of the shaft 112 may be problematic with a conventional threaded insert or a conventional threaded point. Similarly, alignment of the blades of a broadhead with the sides of the shaft 112 and/or the fletchings 116 may be problematic with a conventional threaded insert or conventional threaded broadhead.
In one aspect of the present invention, the head 114 is configured for insertion directly into the shaft 112. For example, a first point 114a may be provided comprising a single body including both a tip 150 and arrow insert 152, as illustrated in
In another aspect, the head 114 may be adapted to engage a receiver 170 associated with the shaft 112. The receiver 170 may include a cross-section matching the cross-section of the shaft 112. For example, if the shaft were round, then the receiver would be round. In the case of a RT (or other rounded polygon) shaft, the receiver 170 may also be a RT (or other similarly shaped rounded polygon). In one aspect, the receiver 170 may include a taper to account for an arrow head with a different diameter than the shaft 112. For example, if the head were larger in cross-section than the shaft, then the receiver 170 may include an outward taper to provide a smooth transition from the smaller shaft to the larger head.
As illustrated in
In one aspect, the extension 172 may be in the form of a shank or stud. The extension 172 may be threadless. In a further aspect, the extension 172 may have a RT cross section, another rounded polygonal cross-section, a triangular cross section, or may be round. The aperture 184 may include the same cross sectional shape as the extension 172 to ensure an accurate mated connection. The extension 172 may be adapted to frictionally engage the aperture 184 of the receiver 170. As illustrated in
With further reference to
As shown in
In one aspect, the collar 180 may include one or more fasteners 186, such as adjustable set screws. The set screws may be configured to retain the extension 172 within the receiver 170 upon actuation thereof. For instance, the second point 114b or the second broadhead 115b may be inserted into the aperture 184, and the set screws tightened to secure the extension 172. In one aspect, the set screws may be allen head set screws and may be adjusted with a hex or allen key. This engagement may allow for alignment and secured fixed positioning of the head 114, the shaft 112, the fletchings 116, and the nock 118.
In the case of the extension 172 and the aperture 184 being triangular, of a RT cross section, of another rounded polygonal cross section, or any other shape that prevents relative rotation between engaged elements, this configuration allows for automatic alignment between similarly shaped features. In the case of a round extension 172 and aperture 184, the head 114 may be rotated relative to the shaft, and fasteners 186 may be used to secure the head 114 in place.
In another embodiment, an insertable link 200 may be provided for connecting a head 114 to the shaft 112, as illustrated in
In one aspect, the link 200 may include a collar 210 and an insertion portion 212. The collar 210 may include a taper for engaging a head 114 of a different cross sectional size than the shaft. The insertion portion 212 may include a RT cross section and may be configured to be inserted into the shaft 112. The link 200 may be configured to frictionally engage the shaft. For example, the insertion portion 212 may include knurling, grooves, recesses, ridges, or other surface formations for engaging an inner surface of the shaft 112. An adhesive may be used to retain the insertion portion 212 within the shaft 112.
The collar 210 of the insertable link 200 may include a protruding extension 214, such as a stud or shaft. The extension 214 may have a RT cross section, a triangular cross section, or a round cross section. In one aspect, the extension 214 may include knurling and/or grooves.
With reference to
As illustrated in
The receiver 170 or the link 200 may be constructed of steel, aluminum, stainless steel, brass or the like. In one aspect, the receiver 170 or the link 200 may be weighted and/or may be constructed in a variety of weights. The weight and strength of an insert such as receiver 170 or link 200 may add weight to the front of the arrow that is not present in conventional inserts. This allows for adjustment of “front of center” (FOC) balance position.
The improved arrow system of the current invention allows for near perfect alignment of the arrow shaft with the nock, fletchings and points. This allows for lockable alignment of the nock with the shaft and offers tunability of the points to the arrow shaft. A conventional insert or nock insert used with a conventional round shaft is glued in place and then usually reheated so the nock or hunting point can be rotated to align with the arrow shaft and fletchings. This poses a problem with carbon arrows. Carbon arrows may not be heated because of damage to the carbon fibers. While heating the arrows enables the inserts to be rotated within the arrow shaft it also can reduce the strength of the shaft and the glue creating poor connections between the insert and arrow. The shape of the RT arrow shaft and the adjustable insert of the present invention as well as the unique shape knock solves this issue. The arrow shaft also allows for different flexural rigidity which will cut down the production of many shaft sizes.
While the invention has been described with reference to specific examples, it will be understood that numerous variations, modifications and additional embodiments are possible, and all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the invention. Also, the drawings, while illustrating the inventive concepts, are not to scale, and should not be limited to any particular sizes or dimensions. Accordingly, it is intended that the present disclosure not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.
This application claims priority to U.S. PROVISIONAL Application Ser. No. 62/236,884, filed Oct. 3, 2015, the disclosure of which is hereby incorporated by reference.
Number | Date | Country | |
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62236884 | Oct 2015 | US |