Embodiments of the present invention generally relate to a reinforced lighted nock adapted for use with arrows or crossbow bolts that is structurally more robust in comparison to previously known lighted nocks.
A nock fits into or attaches to the trailing end of an arrow or a crossbow bolt and acts as the means to transfer launching energy between the projectile and the launching device. Lighted nocks, which include a power source as well as a light source powered by the power source, have become increasingly desirable, because they allow tracking the arrow or bolt in flight, as well as locating the arrow or bolt after the shot is taken.
As illustrated in
Distal end 20 of nock 10 contains, at its distal end a slot or a groove that provides an opening 40 that is configured to receive the string of a bow or crossbow. Distal end 20 also includes button 50, which may be transparent to allow light produced within nock 10 to be transmitted outside through button 50, and which is configured to turn on the light source of nock 10 when depressed (for example, when depressed due to the tension of the crossbow string during operation). In embodiments in which nock 10 is a lighted nock, nock 10 may also include an internal power source such as a battery to power the internal lighting mechanism. For example, proximal end 80 may be one end of a battery, the other end of which is within intermediate portion 60 (and not depicted in
Conventional lighted nock systems for both bows and crossbows utilize an optically clear polymeric construction design to transmit light from an LED within the assembly to the outside of the assembly for tracking of the projectile flight, and projectile location after it has stopped flight. Unfortunately, the choices of polymers that are suitable for this application are fairly limited with clear polycarbonate being the most common. The strength of clear polycarbonate is typically limited to a yield strength near 9,000 psi. This has generally been found to not be sufficient, as clear plastic nocks have a history of breakage in normal operation. The breakage of these nocks has become increasingly severe as bows and crossbows have become more powerful. While most nocks have the potential to break upon the projectile striking a target, it has been observed many times that some crossbows will break clear polymeric bodied nocks during the act of firing the projectile. This is very dangerous to the archer and may potentially cause catastrophic damage to the bow or crossbow.
For these reasons, there is a need for a lighted nock adapted for use with arrows or crossbow bolts that is structurally more robust in comparison to previously known lighted nocks.
The nock in certain embodiments of the current invention includes a structural support piece that substantially surrounds and structurally supports the distal end of the nock, which may be made of a clear polymeric material to allow the transmission of light. In some of these embodiments, the nock contains a light source such that light emitted from the light source is transmitted through the clear polymeric material and at least partially redirected by the structural support piece (which in certain aspects of the certain embodiments may include a reflective metallic material, such as one or more metals (including one or more metal alloys)) in the backwards direction. As a result, the light from the nock is more focused in the backwards directions (for example, the directions contained within a solid angle of π steradians centered around the distal end of the nock and the axis formed by the line between the distal end of the nock at an instant during its flight and the point of release of the nock) compared to the nock without the structural support piece.
The structural support piece may be constructed of or include aluminum or other structural support materials such as Mg, Ti, steel, stainless steel, and/or high strength, structural polymeric or composite materials. Structural polymer materials that may be used to construct the structural support piece may include nylon, delrin, carbon reinforced polymers, fiberglass reinforced polymers, PEEK, PMMA, and/or urethane. Additional polymers or composites serving the same purpose of supporting the less structurally robust clear polymeric piece in a lighted nock may be used in embodiments of the invention.
The nock in certain embodiments of the current invention includes a structural support piece that substantially surrounds and structurally supports the distal end of the nock. Both the structural support piece and the distal end of the nock can be made from a clear ceramic material such as aluminum oxynitride (AlON). Both the structural support piece and the distal end of the nock can also be made from nanoparticle aluminum oxide (Al2O3) or nanoparticle spinel (MgAl2O4). In certain embodiments, the structural support piece and the distal end can be separate components. In other embodiments, the structural support piece and the distal end can be manufactured as a single, integrated piece. The nock contains a light source such that light emitted from the light source is transmitted through the distal end and at least partially redirected by the structural support piece in the backwards direction. The use of a clear ceramic support embodiment would be beneficial in applications in which it is desired to have a greater amount of light transmitted from the sides of the structural piece when compared with the opaque structural material embodiment.
Structural support piece 275 has a cylinder-like shape and substantially surrounds and structurally supports distal end 220 of nock 200. The distal end of structural support piece 275 contains a groove so that structural support piece 275 does not obstruct opening 240. In this embodiment, the distal end of structural support piece 275 contains four holes 285 (only two of which are visible in
The distal end of structural support piece 275, which is cylindrically shaped, has a cross-sectional radius that is greater than that of the proximal end of structural support piece 275, as depicted in
Nock 200 has components similar to those of the nock 100 shown in
In certain embodiments, structural support piece 275 is made from an aluminum alloy, which in this embodiment has a yield strength of 75,000 psi, which is much greater than the yield strength of the clear polymeric material in the distal end 220 of nock 200 that has an approximate yield strength of 9000 psi. Structural support piece 275 can also be made from a clear ceramic material such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4). When the structural support piece 275 and the distal end 220 are made of, for example, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), the structural support piece 275 and the distal end 220 can either be separate pieces, or manufactured as a single, integrated piece. It is generally preferable that the weight of the structural reinforcing piece and the entire assembly be as lightweight as possible. This is desirable, for example, to maintain good weight forward of center for flight stability. Each of the aforementioned aluminum alloy, AlON, nanoparticle aluminum oxide (Al2O3), and nanoparticle spinel (MgAl2O4) allow and can be utilized to accomplish such design objectives.
Structural support piece 275 may be constructed of or include other structural support materials such as Mg, Ti, steel, stainless steel, and/or high strength, structural polymeric or composite materials. Typically, such structural support materials (including aluminum) are not transparent or translucent to light emissions from the light source of nock 200 (which may be an LED), which distinguishes them from, for example, conventional clear polymeric materials, a clear ceramic material such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), that can be used in constructing distal end 220 of nock 200. Structural polymer materials that may be used to construct structural support piece 275 may include: nylon, delrin, carbon reinforced polymers, fiberglass reinforced polymers, PEEK, PMMA, and/or urethane. Additional polymers or composites serving the same purpose of supporting the less structurally robust clear polymeric piece in a lighted nock may be used in embodiments of the invention. As noted above, structural support piece 275 may also be made from, for example, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4).
The distal end of structural support piece 375, which is cylindrically shaped, has a cross-sectional radius that is greater than that of the proximal end of structural support piece 375, as depicted in
Nock 300 includes structural support piece 375 that provides structural support for distal end 320, which is made from a clear polymeric material or polycarbonate to allow the transmission of light from the light source of nock 300 to the outside. In certain embodiments, structural support piece 375 is made from an aluminum alloy, which in this embodiment has a yield strength of 75,000 psi, which is much greater than the yield strength of the clear polymeric material in the distal end 320 of nock 200 that has an approximate yield strength of 9000 psi. Structural support piece 375 can also be made from, for example, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4).
Structural support piece 375 may be constructed of or include other structural support materials such as Mg, Ti, steel, stainless steel, or high strength, structural polymeric or composite materials. Typically, such structural support materials (including aluminum) are not transparent or translucent to light emissions from the light source of nock 300 (which may be an LED), which distinguishes them from, for example, the clear polymeric materials, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), that can be used to construct distal end 320 of nock 300. Structural polymer materials that may be used to construct structural support piece 375 may include: nylon, delrin, carbon reinforced polymers, fiberglass reinforced polymers, PEEK, PMMA, and urethane. Additional polymers or composites serving the same purpose of supporting the less structurally robust clear polymeric piece in a lighted nock may be used in embodiments of the invention.
Structural support piece 475 has a cylinder-like shape and substantially surrounds and structurally supports distal end 420 of nock 400. Because of the absence of a groove and opening on distal end 420 of nock 400, structural support piece 475 need not have a matching groove, unlike the embodiments discussed in connection with
Furthermore, in this embodiment, the distal end of structural support piece 475 contains four holes 485 (only two of which are visible in
The distal end 420 of structural support piece 475, which is cylindrically shaped, has a cross-sectional radius that is greater than that of the proximal end of structural support piece 475, as depicted in
Structural support piece 475 provides structural support for distal end 420, which is made from a clear polymeric or polycarbonate material to allow the transmission of light from the light source of nock 400 to the outside. Distal end 420 can also be made from, for example, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4). In certain embodiments, structural support piece 475 is made from an aluminum alloy, which in this embodiment has a yield strength of 75,000 psi, which is much greater than the yield strength of the clear polymeric material in the distal end 420 of nock 400 that has an approximate yield strength of 9000 psi. Structural support piece 475 can also be made from, for example, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4).
Structural support piece 475 may also be constructed of or include other structural support materials such as Mg, Ti, steel, stainless steel, or high strength, structural polymeric or composite materials. Typically, such structural support materials (including aluminum) are not transparent or translucent to light emissions from the light source of nock 400 (which may be an LED), which distinguishes them from, for example, conventional polymeric materials, clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4) that may be used to construct the distal end 420 of nock 400. Structural polymer materials that may be used to construct structural support piece 475 may include: nylon, delrin, carbon reinforced polymers, fiberglass reinforced polymers, PEEK (polyether ether ketone), PMMA (polymethyl methacrylate), and urethane. Additional polymers or composites serving the same purpose of supporting the less structurally robust clear polymeric piece in a lighted nock may be used in embodiments of the invention.
Besides the increased structural integrity that embodiments of this invention offer in comparison to polymeric nocks lacking a structural support piece, they also offer lighting performance advantages. In conventional lighted nocks that only or substantially only include a clear polycarbonate body, the enclosed light within the assembly is free to disburse in all directions in a semi-diffuse pattern. By encasing the light and polycarbonate subassembly within an anodized aluminum assembly (which may also serve as a structural support piece), a focusing effect may be obtained that significantly increases the visual light intensity of the lighted nock when viewed from behind the projectile, as an archer would do after releasing the arrow or bolt. This effect is similar to what can be observed in a flashlight that contains a reflector piece in proximity to the light bulb, which results in a greater intensity of the projected light compared to a situation in which the reflector is absent.
In embodiments of the current invention in which anodized aluminum is used as the structural support piece, this effect is caused by the natural reflectivity of anodized aluminum which is approximately 80%. As a result, the light intensity when viewed from the archer's perspective can be more than double the intensity compared to the intensity that can be obtained based on conventional lighted nocks. It is well known that the reflectivity of materials, including structural support materials, varies from material to material. Accordingly, embodiments of the present invention enable the reflectivity in the backwards direction to be adjusted or optimized by choosing a structural support material that has a desired reflectivity property, and shaping the structural support material for providing reflection in that backwards direction.
However, where the nock (such as nock 505 of
Embodiments of the present invention may be used with a variety of nock designs. For example,
In
Nock 600 may have components generally similar to those of the nocks discussed in earlier embodiments. For example, distal end 620 may at least in part be made from, for example, a clear polymeric or polycarbonate material, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 600. The embodiment depicted in
In this embodiment, proximal end 723 and distal end 775 of structural support piece 725 may be both made of structural support materials as discussed earlier. Alternatively, only one of proximal end 723 and distal end 775 (e.g., distal end 775) of structural support piece 725, may be made of structural support materials. Further, distal end 720 of nock 700 may also at least in part be made from a structural support material. For example, the end portion 721 of distal end 720 (which includes a groove providing opening 740) may be made from such a structural support material.
Nock 700 may have components generally similar to those of the nocks discussed in earlier embodiments. For example, distal end 720 may at least in part be made from, for example, a clear polymeric or polycarbonate material, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 700. The embodiment depicted in
Nock 800 can include an accelerometer-activated system with a replaceable battery and a microprocessor. In another embodiment of nock 800, the accelerometer-activated system could include a non-replaceable battery.
The nock 800 of
Nock 800 may have components generally similar to those of the nocks discussed in earlier embodiments. For example, distal end 820 may at least in part be made from, for example, a clear polymeric or polycarbonate material, a clear ceramic material such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 800. The embodiment depicted in
Nock 900 can also include an accelerometer-activated system with a replaceable battery and a microprocessor. In another embodiment of nock 900, the accelerometer-activated system could include a non-replaceable battery
Nock 900 as shown in of
Nock 900 may have components generally similar to those of the nocks discussed in earlier embodiments. Distal end 920 may at least in part be made from, for example, a clear polymeric or polycarbonate material, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 900. The embodiment depicted in
In this embodiment, proximal end 1023 and distal end 1075 of structural support piece 1025 may be both made of structural support materials as discussed earlier. Alternatively, only one of proximal end 1023 and distal end 1075 (e.g., distal end 1075) of structural support piece 1025, may be made of structural support materials. Further, distal end 1020 of nock 1000 may also at least in part be made from a structural support material. For example, the end portion 1021 of distal end 1020 (which includes a groove providing opening 1040) may be made from such a structural support material.
Nock 1000 may have components generally similar to those of the nocks discussed in earlier embodiments. Distal end 1020 may at least in part be made from, for example, a clear polymeric or polycarbonate material, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 1000. The embodiment depicted in
In this embodiment, proximal end 1123 and distal end 1120 of structural support piece 1125 may be both made of structural support materials as discussed earlier. Alternatively, only one of proximal end 1123 and distal end 1120 (e.g., distal end 1120) of structural support piece 1125, may be made of structural support materials. Further, distal end 1120 of nock 1100 may also at least in part be made from a structural support material. For example, the end portion 1121 of distal end 1120 (which includes a groove providing opening 1140) may be made from such a structural support material.
Nock 1100 may have components generally similar to those of the nocks discussed in earlier embodiments. For example, distal end 1120 may at least in part be made from a clear polymeric or polycarbonate material, AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), to allow light to escape from the back of nock 1100. The embodiment depicted in
As discussed above, in certain embodiments of the current invention, the preferably aluminum body of the nock includes a clear polycarbonate insert piece or clear insert piece made from, for example, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), that permits light transmission through that insert piece. The aluminum body of the nock may also provide structural support to the insert piece that is used with arrows and crossbow bolts.
Metallic structural support pieces used in embodiments of the current invention may be manufactured using machining, similar to the techniques used in manufacturing metallic fittings and components used in ordinary consumer products. For example, a turning center, CNC (computer numerical controlled) lather, CNC mill, screw machine, or a combination thereof may be used for this purpose. Structural support pieces made from structural polymeric materials or composite polymeric materials, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4), may typically be manufactured through using injection molding, but could also be manufactured using machining techniques. The clear polycarbonate or other light transmitting material would typically be manufactured via injection molding.
The structural support piece may be attached to the insert piece made from a polymer, a clear ceramic such as AlON, nanoparticle aluminum oxide (Al2O3), or nanoparticle spinel (MgAl2O4) through the use of a snap or compression fit, through the use of matching male-female threads on these components and/or through the use of adhesives. For example, to implement a snap of compression fit between components of the invention that are envisioned to attach to one another, grooves and corresponding protrusions may be formed on the surfaces of such components. More generally, other conventional ways of assembling components of the lighted nocks of the current invention can also be utilized.
Embodiments of the present invention have been described for the purpose of illustration and are not limiting, and may be practiced with modifications and alterations limited only by the spirit and scope of the appended claims which are intended to cover such modifications and alterations, so as to afford broad protection to the various embodiments of invention and their equivalents.
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/748,526, filed Jan. 3, 2013, herein incorporated by reference in its entirety.
Number | Date | Country | |
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61748526 | Jan 2013 | US |