High impact strength lighted nock assembly

Abstract

A high impact strength lighted nock assembly for an arrow that is activated when the arrow is fired with a bowstring. The lighted nock assembly includes a nock molded from a high impact strength, transparent polymeric material containing at least 10% by weight reinforcing fibers. The nock includes a head configured to engage with the bowstring and a shank configured to couple with a rear end of the arrow. The shank includes a recess extending in a distal end of the shank toward the head. A light assembly including a light emitting device is located in the recess in the shank that is electrically coupled to a battery. A switch is electrically coupled to the light emitting device and the battery that is triggered when the arrow is tired to activate the light emitting device.

Claims

1. A lighted nock assembly, comprising: a nock comprising a head configured to engage with a bowstring, and a shank that includes (i) a cavity having an end located proximate the head and (ii) an opening; a light assembly comprising a light emitting device disposed at the end of the cavity and optically coupled to the head of the nock, and a battery having (i) a first end disposed within the cavity and (ii) a second end disposed external to the cavity, wherein the light emitting device transitions from a deactivated state before an arrow is fired to an activated state after the arrow is fired; and a battery stop at least partially disposed within a bushing and coupled to the second end of the battery, the battery stop including a first recess, wherein a gasket at least partially resides within the first recess and a second recess defined by the bushing, the gasket releasably coupling the battery stop to the bushing and resisting longitudinal translation of the battery relative to the bushing, wherein the shank translates within the bushing between an activated configuration that activates the light emitting device and a deactivated configuration that deactivates the light emitting device without removing the light assembly from the bushing.

2. The lighted nock assembly of claim 1, wherein the nock comprises a polymeric material that comprises one of polycarbonate, polyurethane, polyetherimide, nylon, polyetheretherketone, polyetherketone, thermoplastic polyimide, or combinations thereof.

3. The lighted nock assembly of claim 1, wherein the nock comprises a polymeric material that comprises a reinforcing material of about 20% by weight glass fibers or filamentous glass.

4. The lighted nock assembly of claim 1, wherein the gasket comprises a frictional member that releasably secures the battery stop to the bushing.

5. The lighted nock assembly of claim 1, wherein (i) the light assembly, (ii) the nock, (iii) the battery, and (iv) the battery stop are removable from the bushing as a single assembly.

6. The lighted nock assembly of claim 1, further comprising a removable tab stop located in a gap between the head of the nock and the bushing that prevents the nock from translating to the activated configuration.

7. The lighted nock assembly of claim 6, wherein the removable tab stop comprises a handle portion has at least one major dimension that is at least about two times greater than an outside diameter of the arrow.

8. The lighted nock assembly of claim 1, wherein radial outward forces applied to the battery stop during translation from both (i) the deactivated configuration and (ii) the activated configuration are contained within the bushing.

9. The lighted nock assembly of claim 1, wherein the battery stop further includes: a groove extending around a least a portion of a periphery of the battery stop; and a friction member disposed within the groove and engaging at least a portion of the bushing.

10. The lighted nock assembly of claim 1, wherein the first end of the battery is configured to translate within the cavity to (i) electrically couple to the light emitting device when the light emitting device is in the activated state and (ii) electrically decouple from the light emitting device when the light emitting device is in the deactivated state.

11. The lighted nock assembly of claim 1, wherein the bushing includes a flange that engages with the battery stop to prevent displacement of the battery stop after the arrow is fired.

12. The lighted nock assembly of claim 1, wherein the nock comprises a polymeric material that comprises a light transmittance of at least 75%.

13. A plurality of matched weight arrows comprising: a first arrow having the bushing and the lighted nock assembly of claim 1, wherein the first arrow has a first weight; and a second arrow having a bushing and a nock without a light assembly located in the bushing, the second arrow having a second weight substantially equal to the first weight.

14. A lighted nock assembly, comprising: a nock comprising: a head configured to engage with a bowstring; and a shank including a cavity; a light assembly comprising a light emitting device disposed within the cavity and optically coupled to the head of the nock, wherein the light emitting device is in (i) a deactivated state before an arrow is fired due to the light emitting device being electrically decoupled from a battery and (ii) an activated state after the arrow is fired due to the light emitting device being electrically coupled with the battery; and a battery stop disposed within a bushing and coupled to the battery at a location external to the cavity, the battery stop including a first recess, wherein a frictional member at least partially resides within the first recess and a second recess of the bushing to releasably couple the battery stop to the bushing and resist longitudinal translation of the battery relative to the bushing such that (i) the light assembly, (ii) the nock, and (iii) the battery stop are removable from the bushing as a single assembly, wherein the nock is configured to translate, within the bushing, between (i) an activated configuration characterized by the battery being electrically coupled with the light emitting device in the activated state and (ii) a deactivated configuration characterized by the battery being electrically decoupled from the light emitting device in the deactivated state.

15. A method of assembling a lighted arrow, the method comprising: inserting a distal portion of a bushing into a rear end of a shaft, the bushing comprising a center opening and a first recess; providing a nock, the nock comprising a head configured to engage with a bowstring and a shank configured to be inserted within the center opening of the bushing; attaching a light emitting device of a light assembly within a cavity of the shank, the light assembly comprising a battery at least partially disposed within the cavity and mechanically coupled to the light emitting device; attaching a battery stop to the battery at a location offset from the shank and external to the cavity, the battery stop including a second recess; inserting (i) the battery stop, (ii) the light assembly, and (iii) the nock into the center opening in the bushing, wherein a frictional member is disposed at least partially within the first recess and at least partially within the second recess to mechanically couple the battery stop within the bushing, wherein the battery stop resists longitudinal translation of the battery relative to the bushing; and translating the nock within the center opening of the bushing between an activated configuration that activates the light emitting device and a deactivated configuration that deactivates the light emitting device without removing the light assembly from the bushing.

16. The method of claim 15, further comprising molding the nock from a polymeric material including a reinforcing material of about 20% by weight glass fibers or filamentous glass.

17. The method of claim 15, wherein the frictional member releasably secures the battery stop to the bushing.

18. The method of claim 15, further comprising removing (i) the light assembly, (ii) the nock, (iii) the battery, and (iv) the battery stop from the bushing as a single assembly.

19. The method of claim 15, further comprising inserting a removable tab stop in a gap between the head of the nock and the bushing that prevents the nock from translating to the activated configuration.

20. A method of making a plurality of matched weight arrows, the method comprising: preparing a first arrow in accordance with the method of claim 15, wherein the first arrow has a first weight; and preparing a second arrow in accordance with the method of claim 15 without the light assembly, the second arrow have a second weight substantially equal to the first weight.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 is a perspective view of a nock for an archery arrow in accordance with an embodiment of the present disclosure.

(2) FIG. 2 is a top view of the nock of FIG. 1.

(3) FIG. 3 is a side view of the nock of FIG. 1.

(4) FIG. 4 is an end view of the nock of FIG. 1.

(5) FIG. 5 is an end view of the nock of FIG. 1.

(6) FIGS. 6A and 6B are sectional views of a lighted nock assembly in accordance with an embodiment of the present disclosure.

(7) FIGS. 7A and 7B are sectional views of a light assembly in accordance with an embodiment of the present disclosure.

(8) FIG. 7C is a sectional view of an alternate light assembly with multiple acceleration switches in accordance with an embodiment of the present disclosure.

(9) FIG. 8A is a sectional view of a combination lighted nock assembly and bushing in accordance with an embodiment of the present disclosure.

(10) FIG. 8B is a perspective view of the bushing of FIG. 8A.

(11) FIG. 9 is a sectional view of a lighted nock assembly for a half-moon nock in accordance with an embodiment of the present disclosure.

(12) FIG. 10 is a sectional view of a lighted nock assembly for a V-nock in accordance with an embodiment of the present disclosure.

(13) FIG. 11 is a sectional view of a lighted nock assembly for a flat nock in accordance with an embodiment of the present disclosure.

(14) FIG. 12A is a perspective view of an alternate lighted nock assembly used with a bushing in accordance with an embodiment of the present disclosure.

(15) FIG. 12B is cross-sectional view of the lighted nock assembly of FIG. 12A in a deactivated configuration in accordance with an embodiment of the present disclosure.

(16) FIG. 12C is cross-sectional view of the lighted nock assembly of FIG. 12A in an activated configuration in accordance with an embodiment of the present disclosure.

(17) FIG. 13A is an exploded view of the lighted nock assembly of FIG. 12A.

(18) FIG. 13B is a sectional view of the lighted nock assembly of FIG. 12A without the bushing.

(19) FIGS. 14A and 14B illustrate an interface of the bushing and the nock of FIG. 12A.

(20) FIG. 15 illustrates the light assembly of FIG. 12A.

(21) FIGS. 16A and 16B illustrate the battery stop of FIG. 12A.

(22) FIGS. 17A and 17B illustrate a tab stop for use with a lighted nock assembly in accordance with an embodiment of the present disclosure.

(23) FIG. 18 illustrates a matched weight arrow that can be used with or without a lighted nock assembly in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

(24) FIGS. 1 through 5 illustrate various views of an exemplary nock 21 in accordance with an embodiment of the present disclosure. The nock 21 is molded from a reinforced polymeric material (or blend of polymeric materials). The nock 21 can be used with or without a light assembly, as will be discussed herein.

(25) For lighted nock applications, the reinforced polymeric material is preferably transparent, but may also be semi-transparent or translucent. Light transmittance of the polymeric material is preferably at least 65%, more preferably at least 75%, and most preferably at least 85%. Nocks for vertical bows and crossbows are often distinguished in their general shape, but both are collectively referred to herein as “nocks”. As used herein, the term “bows” refers generically to both vertical bows and crossbows.

(26) The nock 21 illustrated in FIGS. 1-5 is a clip-on nock. The prongs 23 flex outward 25 until the bowstring is seated in semi-circular opening 27. In order to withstand the forces generated in high-powered bows, the polymeric material must have a high impact strength, but also requires sufficient flexibility to permit the nock prongs 23 to deflect when engaging with and disengaging from the bowstring 29. The polymeric material preferably has a tensile strength of greater than about 10,000 pounds per square inch (psi) as determined by ASTM D638. The polymeric material preferably has a flexural strength of greater than about 20,000 psi as determined by ASTM D790. The polymeric material preferably has a flexural modulus of greater than 0.50×10.sup.6 psi. The flexural modules is the ratio, within the elastic limit, of stress corresponding to strain.

(27) The reinforcing material can be plastic, metal, ceramic, glass, wood, and/or natural and synthetic composite material, and so forth, as well as combinations thereof. For example, reinforcing material can be glass, carbon, titanium, aluminum, stainless steel, talc, mica, quartz, Wollastonite, as well as combinations thereof. The form of the reinforcing material can be fibers (including woven, nonwoven (e.g., felt), chopped, continuous, and/or random fibers), flakes, beads, particles, and combinations thereof. In one embodiment, the reinforcing material has an average aspect ratio (i.e., the ratio of a structure's size in different dimensions) of at least about 5:1, and more preferably at least about 7:1, and most preferably about 10:1.

(28) In one embodiment, the nock 21 is molded from a high impact, transparent polycarbonate material filled with between about 10% to about 30% by weight reinforcing material. In one embodiment, the reinforcing material is about 20% by weight glass fibers or filamentous glass. The glass fibers preferably have diameters in the range of about 5 microns to about 100 microns and a length of less than about 2 millimeters. One polymeric material suitable for the present high impact nock is available from RTP Company of Winona, Wis. under the product designation RTP 303. While the material is substantially transparent, it exhibits a slight yellow tint. Polyurethane, polyetherimide, nylon, polyetheretherketone, polyetherketone, and thermoplastic polyimide may also be used. Other polymeric materials suitable for the present nock 21 are disclosed in U.S. Pat. No. 9,434,334 (Marur et al.); U.S. Pat. No. 7,767,738 (Gagger et al.) and U.S. Pat. No. 5,859,119 (Hoefflin), which are hereby incorporated by reference.

(29) Transparency is the physical property of allowing light to pass through a material without being scattered. Translucency, on the other hand, allows light to pass through, but the photons can be scattered either at interfaces where there is a change in index of refraction or internally. The nock 21 is preferably constructed from a polymeric material that is transparent (or transparent to certain wavelengths of light due to color tinting of the polymer), while the reinforcing material scatters some portion of the light from the light emitting device. Consequently, portions of the nock 21 both transparent and translucent. That is, a portion of the light emitted by the light emitting device is transmitted through the nock 21 and a portion of the light is scattered by the reinforcing material.

(30) By altering the percentage of reinforcing material in the polymeric material it is possible to engineer the optimum balance of transmitted light (which creates more directional light source that is visible at a greater distance) and scattered light (which creates a hemispheric distribution of light that is visible from more angles). Applicants have identified a reinforcing material content of about 10% to about 30% by weight as providing optimal light distribution for lighted nock applications.

(31) The nock 21 illustrated in FIGS. 1-5 may be used with the crossbows illustrated in U.S. Pat. No. 9,494,379 (Yehle) entitled Crossbow, filed Apr. 14, 2016 and U.S. patent application Ser. No. 15/433,769 entitled Crossbow, filed Feb. 15, 2017, both of which are hereby incorporated by reference. In particular, the anti-dry fire mechanism disclosed in the patents noted above preferably engages with the nock 21 in the region 31 behind the bowstring 29. The region 31 is preferably at least about 0.1 inches. Flat regions 33 illustrated in FIG. 3 are preferably separate by a distance 35 of about 0.250 inches, which corresponds to a gap between fingers on a bowstring catch for the crossbow in the patents noted above.

(32) FIGS. 6A and 6B are cross-sectional views of the lighted nock assembly 20 in accordance with an embodiment of the present disclosure. In the illustrated embodiment, the light assembly 24 is a “bobber-light” that includes light emitting device 26, such as a filament light, an LED, or other light producing device, electrically coupled to battery 28. The nock 21 includes recess 22 configured to receive the light emitting device 26.

(33) In the illustrated embodiment, elastomeric member 30 maintains gap 32 between light emitting device 26 and the battery 28 corresponding to the battery 28 being disconnected from the light emitting device 26 (see FIG. 7A). The light assembly 24 is biased to the deactivated configuration by the elastomeric member 30.

(34) As best illustrated in FIG. 6B, on launch the bowstring (not shown) applies force 34 to displace the nock 21 into the arrow shaft 36, reducing or closing the gap 38. Bottom surface 40 of the recess 22 simultaneously displaces the light emitting device 26 toward the battery 28 to complete the circuit and altering the light emitting device to an activated state (see e.g., FIG. 7B). Elastomeric insert 46 secures the battery 28 to the inside surface 44 of the arrow shaft 36 so as to create force 48 that opposes the force 34 applied to the light emitting device 26 by displacement of the nock 21. The opposing forces 34 and 48 compress the elastomeric material 30 and substantially closes the gap 32, resulting in the battery 28 being electrically coupled to the light emitting device 26 (see FIG. 7B). The light emitting device 26 is now in the activated state.

(35) The light assembly 24 is moved to the deactivated configuration by pulling the nock 21 slightly out of the arrow shaft 36 as illustrated in FIG. 6A and reestablishing the gap 38. The elastomeric material 30 simultaneously displaces the light emitting device 26 away from the battery 28 and opens the circuit to deactivate the light emitting device 26 (see e.g., FIG. 7A). The light assembly 24 is normally biased to the deactivated configuration absent an external force.

(36) FIGS. 7A and 7B illustrate the light assembly 24 in accordance with an embodiment of the present disclosure. FIG. 7A illustrates the light assembly 24 in the deactivated configuration and FIG. 7B illustrates the activated configuration. The light emitting device 26 includes a pair of electrical contacts 50 and 52 that extend rearward within housing 54 toward the battery 28. In the illustrated embodiment the contact 50 is engaged with one pole of the battery 28 at all times. In the deactivated configuration the contact 52 is separated from the other pole 56 of the battery 28. The elastomeric member 30 maintains that separation. In another embodiment, a metal spring may be located generally concentrically around the pole 56 to serve as both the contact 50 and to provide the biasing force of the elastomeric member 30. In both embodiments the light assembly 24 is biased to the inactive configuration.

(37) As illustrated in FIG. 7B, when the light assembly 24 is subject to a longitudinal compressive force 58 the elastomeric member 30 is elastically deformed and compressed a sufficient amount so the contact 52 engages with the other pole 56 of the battery 28, completing the circuit so the light emitting device 26 is in the activated state. When the longitudinal compressive force 58 is removed the elastomeric member 30 automatically returns to its original size and shape (see FIG. 7A), which displaces the contact 52 way from the pole 56 of the battery 28 to move the light emitting device 26 to the deactivated state.

(38) In another embodiment, the light emitting device 26 is secured in the recess 22 in the nock 21. When the nock 21 is pulled away from the arrow shaft 36 and the gap 38 is reset, the light emitting device 26 and the contact 52 are also displaced away from the pole 56 of the battery 28 and the light emitting device 26 is in the deactivated state. The elastomeric member 30 is not required in this embodiment.

(39) In an alternate embodiment illustrated in FIG. 7C, one or more accelerometer switches or an integrated circuit accelerometer 100A, 100B (“100”) control activation of the light emitting device 26, such as disclosed in U.S. Pat. No. 7,993,224 (Brywig), which is hereby incorporated by reference. The switches 100 respond to the forces resulting from the acceleration of the arrow upon release or deceleration of the arrow upon impact with a target. In one embodiment, multiple accelerometer switches 100 are provided to sense acceleration and/or deceleration along multiple axes 102, 104. For example, axis 102 may be located along a longitudinal axis of the arrow and the axis 104 is perpendicular to the axis 102. Triggering of the light emitting device 26 preferably requires a combination of acceleration and/or deceleration signals along the two different axes 102, 104.

(40) FIGS. 8A and 8B illustrate an alternate lighted nock assembly 20 used in combination with bushing 60 in accordance with an embodiment of the present disclosure. The bushing 60 is a hollow cylinder that is interposed between the nock 21 and the arrow shaft 36 to reinforce the shaft 36. The light assembly 24 extends through center opening 62 in the bushing 60. The bushing 60 is preferably aluminum or other light-weight metal.

(41) The present disclosure is not limited to the light assemblies 24 illustrated herein. The present lighted nock assembly 20 can be modified to operate with a variety of light assemblies, including without limitation the light assemblies disclosed in U.S. Pat. No. 4,340,930 (Carissimi), U.S. Pat. No. 4,547,837 (Bennett); U.S. Pat. No. 5,134,552 (Call et al.); U.S. Pat. No. 6,123,631 (Ginder); U.S. Pat. No. 6,736,742 (Price et al.); U.S. Pat. No. 7,021,784 (DiCarlo); U.S. Pat. No. 7,211,011 (Sutherland); U.S. Pat. No. 7,837,580 (Huang); U.S. Pat. No. 7,931,550 (Lynch); U.S. Pat. No. 7,927,240 (Lynch); U.S. Pat. No. 7,993,224 (Brywig); U.S. Pat. No. 8,342,990 (Price); U.S. Pat. No. 8,540,594 (Chu); U.S. Pat. No. 8,758,177 (Minica); U.S. Pat. No. 8,777,786 (Bay); U.S. Pat. No. 8,944,944 (Pedersen et al.); U.S. Pat. No. 9,140,527 (Pedersen et al.); U.S. Pat. No. 9,151,580 (Pedersen); U.S. Pat. No. 9,243,875 (Minica); U.S. Pat. No. 9,279,647 (Marshall); U.S. Pat. No. 9,279,648 (Marshall); U.S. Pat. No. 9,279,649 (Bay); U.S. Pat. No. 9,404,720 (Pedersen); U.S. Pat. No. 9,423,219 (Pedersen et al.); U.S. Pat. No. 9,518,806 (Pedersen); U.S. Pat. No. 9,546,851 (Kim); 2015/0192395 (Beck), which are hereby incorporated by reference.

(42) The present disclosure is applicable to any nock configuration, including without limitation, flat, half-moon, slotted, and universal nocks, such as disclosed in U.S. Pat. No. 9,441,925 (Palomaki et al.); U.S. Pat. No. 9,285,195 (Palomaki et al.); U.S. Pat. No. 9,212,874 (Harding); U.S. Pat. No. 8,622,855 (Bednar et al.); U.S. Pat. No. 7,189,170 (Korsa et al.); U.S. Pat. No. 5,803,843 (Anderson et al.); D717,389 (Huang); D664,625 (Minica); D641,827 (Errett); and D595,803 (Giles), which are hereby incorporated by reference.

(43) FIG. 9 illustrates a lighted nock assembly 70 including a light assembly 24 and a half-moon nock 72 in accordance with an embodiment of the present disclosure. FIG. 10 illustrates a lighted nock assembly 80 including a light assembly 24 and a V-nock 82 in accordance with an embodiment of the present disclosure. FIG. 11 illustrates a lighted nock assembly 90 including a light assembly 24 and a flat nock 92 in accordance with an embodiment of the present disclosure.

(44) FIGS. 12A through 12C illustrate an alternate lighted nock assembly 120 used in combination with bushing 122 in accordance with an embodiment of the present disclosure. The bushing 122 is preferably constructed from a light weight metal and is sized to be receive within arrow shaft 142. In the illustrated embodiment, the bushing 122 includes shoulder 123 that engages with rear end 125 of the arrow shaft 142.

(45) In the illustrated embodiment, the light assembly 124 is a “bobber-light” that includes light emitting device 126, such as a filament light, an LED, or other light producing device, electrically coupled to battery 128. See also, FIG. 15. The light emitting device 126 is mechanically coupled to a battery 128. Displacing the light emitting device 126 toward the battery 128 activates the light emitting device 126 and displacing the light emitting device 126 away from the battery 128 deactivates the light emitting device. FIG. 12B illustrates the lighted nock assembly 120 in a deactivated configuration 110 and FIG. 12C illustrates the lighted nock assembly 120 in an activated configuration 112, as will be discussed further herein.

(46) As best illustrated in FIG. 12B, the nock 130 includes recess 132 configured to receive the light assembly 124 (see also FIG. 14A). The light emitting device 126 is secured in the recess 132 using a variety of means, such as fasteners, adhesives, inter-locking structures, and the like. Only the light emitting device 126 is attached to the nock 130 so the remainder of the light assembly 124 can move relative to the nock, as illustrated in FIG. 12C. The nock 130 is preferably molded from a transparent, high impact strength polymeric material, as discussed herein.

(47) Battery 128 is secured to inside surface 138 of the bushing 122 by battery stop 136. The battery stop 136 is attached to the battery 128 at a location offset from the nock 130, even in the activated configuration 112. The battery stop 136 is a discrete component from the nock 130 and the bushing 122. Consequently, the nock 130 is coupled to the battery stop 136 by the battery 128, such that movement of the nock 130 relative to the bushing 122 is independent from the engagement of the battery stop 136 with the bushing 122.

(48) Distal end 127 of the bushing 122 preferably includes a structure 129, such as a ridge or a shoulder that limits displacement of the battery stop 136 in direction 131. The tolerances on the battery stop 136 are such that it can slide within the bushing 122, but substantially limits radial displacement of the battery 128 within the arrow shaft 142. This configuration also serves to reinforce the nock 130 from torque applied by a bowstring. These forces are substantially contained within the bushing 122, rather than the arrow shaft 142.

(49) In the illustrated embodiment, the battery 128 is glued to center opening 148 that extends through the battery stop 136. The center opening 148 permits the battery stop 136 to be slid along the battery 128 to the optimum location before being glued in place. It is also possible to use a longer battery 128 that extends past distal end of the battery stop 136.

(50) Friction member 134, such as an elastomeric O-ring, is located in recess 135 in the battery stop 136. See also, FIGS. 16A and 16B. The friction member 134 engages with inside surface 138 of the bushing 122 rather than inside surface 140 of the arrow shaft 142. In the illustrated embodiment, inside surface 138 of the bushing 122 includes recess 144 that receives a portion of the friction member 134. Locating the O-ring 134 in the opposing recesses 135, 144 resists longitudinal displacement of the battery 128 in the bushing 122 a sufficient amount to permit the nock 130 to be pulled to reset the gap 152 to the deactivated configuration 110, without removing the lighted nock assembly 120 from the bushing 122 (see FIG. 12C). By applying additional pulling force to the nock 130, the entire lighted nock assembly 120 (light assembly 124, battery stop 136, and nock 130) can be removed from the bushing 122 and replaced.

(51) Because the lighted nock assembly 120 is contained within the bushing 122, forces applied to the nock 130 during launch are transmitted to the shaft 142 through the bushing 122. For example, radial outward forces 146 transmitted to the battery stop 136 and friction member 134 are contained by the bushing 122, rather than the arrow shaft 142. Many existing lighted nock systems have components that transfer forces to the inside surface of the arrow shaft, causing arrow shaft fractures. The present system isolates the forces generated by the nock 130 within the bushing 122, so any forces experience by the nock 130 are transmitted to the arrow shalt 142 by the bushing 122, greatly extending arrow life. When combined with a nock molded from a transparent, high impact strength polymeric material, the present lighted nock assembly 120 is suitable for use with high-powered bows and crossbows.

(52) On launch the bowstring (not shown) applies force 150 that displaces the nock 130 into the arrow shaft 142 to the activated configuration 112 shown in FIG. 12C, reducing or closing the gap 152. Bottom surface 154 of the recess 132 simultaneously displaces the light emitting device 126 toward the battery 128, completing the circuit and placing the light emitting device 126 to an activated state. The friction member 134 secures the battery 128 to the inside surface 138 of the bushing 122 so as to create force 156 that opposes the force 150 applied to the light emitting device 126 by displacement of the nock 130. The opposing forces 150 and 156 displace the light emitting device 126 toward the battery 128 to substantially reduce or close the gap 158 and to activate the light emitting device 126.

(53) The light assembly 124 is moved to the deactivated configuration 110 by pulling the nock 130 slightly out of the arrow shaft 142 to reestablish the gap 152, as illustrated in FIG. 12B. The friction member 134 secures the battery stop 136 that is attached to the battery 128 within the bushing 122 in opposition to the nock 130 being pulled away from the bushing 122. Consequently, the light emitting device 126 can be deactivated without removing the light assembly 124 from the bushing 122.

(54) FIGS. 13A and 13B show the lighted nock assembly 120 separated from the bushing 122. Since the battery stop 136 is glued to the battery 128 and the LED 126 is glued to the nock 130, the entire lighted nock assembly 120 can be removed from the bushing 122. In the event the light assembly 124 is not working or the nock 130 damaged, the user can pull the entire lighted nock assembly 120 from the bushing 122 by overcoming the frictional coupling generated by the friction member 134 engaged with the recess 144 (see FIG. 12B) in the bushing 122. A replacement lighted nock assembly 120 is then re-inserted into the bushing 122. This configuration permits the bushing 122 to be permanently attached, such as with an adhesive, to the arrow shaft 142 (see FIG. 12B).

(55) The nock 130 preferably includes one or more ridges 160 that mate with corresponding grooves 162 located on inside surface 138 in center opening 164 of the bushing 122. The ridges 160 and grooves 162 prevent the nock 130 from rotating axially relative to the bushing 122 so the nock opening 166 is retained in the correct orientation relative to the arrow shaft 142. See also, FIGS. 14A and 14B.

(56) FIGS. 17A and 17B illustrate the lighted nock assembly 120 and the bushing 122 with stop tab 170 located in the gap 152 (see FIG. 12A) to prevent inadvertent activation of the light assembly 124. The tab stop 170 is useful for shipping purposes and for carrying arrows containing the present lighted nock assembly 120 in the field. The stop tab 170 includes one or more arms 172 that wrap around the stem of the nock 130 and block the gap 152 from closing. The arms 172 are designed to flex outward during insertion into, and removal from, the gap 152.

(57) In the illustrated embodiment, the tab stop 170 includes a handle portion 174 that is large enough to prevent the nock 130 from being engaged with a crossbow trigger housing, forcing the user to remove the tab stop 170 before nocking the arrow. The handle portion 174 preferably has at least one major dimension 176 that is at least about two times an outside diameter 180 of the arrow shaft 142 (see FIG. 12B) coupled to the nock 130, and more preferably at least about three times the outside diameter of the arrow shaft.

(58) FIG. 18 illustrates a matched weight arrow 190 that can be both lighted and non-lighted, in accordance with an embodiment of the present disclosure. As used herein, “matched weight arrows” refers to a plurality of arrows with the same functional characteristics, such as for example, length, stiffness, weight, and diameter, that exhibit substantially similar flight characteristics when launch from the same bow. The present matched weight arrows 190 have a weight difference of less than about 10%, more preferably less than about 5/a, and most preferably less than about 2%. In operation, matched weight arrows can be used interchangeable without adjusting the sight or scope on the bow.

(59) The arrow 190 includes a threaded front insert 192 that receives an arrow head (not shown), a shaft 194, fletching 196, and a rear opening 198 configured to receive any of the bushings and/or nocks disclosed herein. The present matched weight arrow 190 is configured to have substantially the same weight, whether used with our without the present lighted nock assembly 120, so their flight characteristics are the substantially the same. Consequently, a user can select either a lighted arrow or a non-lighted arrow without having to compensate for different weight arrows.

(60) For a non-lighted arrow 190, for example, the bushing 60 (see FIG. 8B) and the nock 21 (FIG. 1) are inserted into the rear opening 198, without the lighted nock assembly 120.

(61) For a lighted arrow 190, for example, the present lighted nock assembly 120 and bushing 122 is inserted into the rear opening 198. Since the lighted nock assembly 120 and bushing 122 are heavier than just the nock 21 and bushing 60, weight is preferably removed elsewhere from the lighted arrow, such as from the shaft 194, the threaded front insert 192, or the fletching 196, so the lighted arrow weighs substantially the same as a non-lighted arrow. In one embodiment, weight is removed from the front insert 192 of the lighted arrow to offset the weight added by the lighted nock assembly 120. In one embodiment, the rear bushing 122 used with the lighted arrow assembly 120 is lighter than the bushing 60, to offset some or all of the weight difference. In another embodiment, weight is added to the non-lighted arrows, such for example, in the threaded front insert 192 or the rear bushing 60, equal to the amount of weight added by the lighted nock assembly 120 and bushing 122. Consequently, the user can carry both lighted arrows and non-lighted arrows having substantially the same weight and flight characteristics. These matched weight arrows 190 can be used interchangeable without effecting accuracy.

(62) Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within this disclosure. The upper and lower limits of these smaller ranges which may independently be included in the smaller ranges is also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either both of those included limits are also included in the disclosure.

(63) Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the various methods and materials are now described. All patents and publications mentioned herein, including those cited in the Background of the application, are hereby incorporated by reference to disclose and described the methods and/or materials in connection with which the publications are cited.

(64) The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present disclosure is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.

(65) Other embodiments are possible. Although the description above contains much specificity, these should not be construed as limiting the scope of the disclosure, but as merely providing illustrations of some of the presently preferred embodiments. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of this disclosure. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes disclosed. Thus, it is intended that the scope of at least some of the present disclosure should not be limited by the particular disclosed embodiments described above.

(66) Thus the scope of this disclosure should be determined by the appended claims and their legal equivalents. Therefore, it will be appreciated that the scope of the present disclosure fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present disclosure is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” All structural, chemical, and functional equivalents to the elements of the above-described preferred embodiment that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present disclosure, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims.