Linear clutch for use with a bow and an arrow rest
09746277 · 2017-08-29
Inventors
Cpc classification
F41B5/143
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
A clutch for use with an arrow rest is mounted intermediate the arrow rest and the bow. The clutch includes a body having a first end configured to operatively connect to the arrow rest cord and a second end that receives a moveable shaft. The moveable shaft has a first end received in the body and a second end configured to connect to a bow. A spring is received on the shaft and positioned between the shaft and the clutch body. The clutch is moveable between a first position in which the shaft first end is proximate the clutch body first end to facilitate the movement of an arrow rest launcher arm out of an arrow support position, and a second position in which the shaft first end is proximate the clutch body second end to facilitate movement of the arrow rest launcher arm into an arrow support position.
Claims
1. A method for facilitating the movement of an arrow rest launcher arm from an arrow support position to a fire position and back into an arrow support position, the method comprises: a. providing a clutch assembly comprising: (1) a generally cylindrical body having: a second end that defines a cavity therein; and an opposite first end having a connector thereon; (2) an elongated shaft having: a second end having a connector thereon; and a first end that is slidably received in the body second end cavity; (3) a spring received on the shaft intermediate the shaft first end and the body second end; (4) a piston coupled to the elongated shaft so as to form a first cavity intermediate the piston and the cylindrical body first end and a second cavity intermediate the piston and the cylindrical body second end; and (5) a valve formed in at least one of the clutch body or the piston; b. operatively coupling one of the body first end or the shaft second end to the arrow rest arm of an arrow rest; and c. operatively coupling the other one of the body first end or the shaft second end to a portion of a bow that is moveable with respect to the arrow rest.
2. The method of claim 1, wherein operatively coupling one of the body first end or the shaft second end to the arrow rest arm further comprises coupling the one of the body first end or the shaft second end to a portion of the arrow rest cord that is operatively coupled to the arrow rest arm.
3. The method of claim 1, wherein operatively coupling the other one of the body first end or the shaft second end to the portion of the bow that is moveable with respect to the arrow rest further comprises coupling the other one of the body first end or the shaft second end to a portion of the arrow rest cord that is operatively coupled to the bow.
4. The method of claim 1, further comprising the step of firing an arrow from the bow so that the clutch assembly moves between: a. a first position in which the shaft first end is proximate the clutch body first end to facilitate the movement of the arrow rest launcher arm out of an arrow support position; and b. a second position in which the shaft first end is proximate the body second end to facilitate movement of the arrow rest launcher arm into the arrow support position after a fletching on the fired arrow passes the arrow rest.
5. The method of claim 4, wherein when the clutch moves from the first position into the second position, a length of the clutch increases by a sufficient amount to facilitate movement of the arrow rest launcher arm from a fired position into the arrow support position.
6. The method of claim 5, wherein the sufficient amount is approximately 0.75 inches.
7. The method of claim 4, wherein when the user fires the arrow from the bow, the clutch assembly moves between the first position in which the body first end is proximate the shaft first end and the second position in which the body second end is proximate the shaft first end thereby effectively increasing the length of the arrow rest cord.
8. The method of claim 1, wherein the clutch assembly further comprises a piston coupled to the shaft first end.
9. The method of claim 8, further comprising a valve formed in the clutch body, wherein a cavity formed between the piston and the clutch body first end is in fluid communication with the atmosphere via the valve.
10. The method of claim 4, wherein the clutch assembly substantially maintains the second position for a period of time of about 0.001-0.05 seconds prior to the clutch assembly moving from the second position into the first position.
11. The method of claim 1, further comprising, operatively coupling the other of the body first end and the shaft second end to a portion of the bow selected from a group consisting of: a. a bow string; b. a buss cable; and c. a limb of the bow.
12. An arrow rest clutch assembly for use with an arrow rest that is coupled to a bow comprising: a. a generally cylindrical body having: (1) a second end that defines a cavity therein; and (2) an opposite first end having a connector that is adapted to operatively couple to one of an arrow rest or a part of a bow that is movable with respect to the arrow rest; b. an elongated shaft having: (1) a second end having a connector that is adapted to operatively couple to the other of the arrow rest or the part of the bow that is moveable with respect to the arrow rest; and (2) a first end that is slidably received in the body second end cavity; c. a spring received on the shaft intermediate the shaft first end and the body second end; and d. a delay mechanism formed on at least one of the clutch body or the elongated shaft, wherein when the body first end is operatively coupled to the one of an arrow rest or a part of a bow that is moveable with respect to the arrow rest and the shaft second end is operatively coupled to the other of the arrow rest or the part of the bow that is moveable with respect to the arrow rest, the clutch assembly is moveable between: a first position in which the body second end is adjacent the shaft first end to allow a launcher arm of the arrow rest to move into an arrow support position after the bow has been fired; and a second position in which the body first end is adjacent the shaft first end to allow the launcher arm of the arrow rest to move into a fired position in which the arrow rest support arm moves out of the flightpath of a fired arrow, and the delay mechanism maintains the clutch assembly in the second position for a period of time prior to the clutch assembly moving from the second position into the first position.
13. The arrow rest clutch assembly of claim 12, wherein when the clutch assembly is operatively coupled intermediate the arrow rest launcher arm and the portion of the bow that is moveable with respect to the arrow rest launcher arm and an arrow is drawn into a firing position on the bow, the clutch moves from the first position into the second position.
14. The arrow rest clutch assembly of claim 12, wherein the part of the bow that is moveable with respect to the arrow rest is selected from a group consisting of: a. a bow string; b. a buss cable; and c. a limb of the bow.
15. The arrow rest clutch assembly of claim 12, wherein the delay mechanism substantially maintains the clutch in the second position for a period of time of about 0.001-0.05 seconds prior to the clutch moving from the second position into the first position.
16. The arrow rest clutch assembly of claim 12, wherein the delay mechanism further comprises: a. a piston operatively coupled to the shaft first end; b. fluid maintained in the clutch body; c. a first cavity defined intermediate the piston and the clutch body first end and a second cavity defined intermediate the piston and the clutch body second end; and d. at least one hole formed through the piston so that the first cavity is in fluid communication with the second cavity by the at least one hole, wherein the at least one hole is configured to allow fluid to pass between the first cavity and the second cavity so that the clutch assembly can move between the first position and the second position.
17. The arrow rest clutch assembly of claim 15, wherein the period of time is no more than 0.02 seconds.
18. The arrow rest clutch assembly of claim 12, wherein when the clutch moves from the second position into the first position, a length of the clutch increases by about 0.25-2 inches.
19. The arrow rest clutch assembly of claim 12, wherein the delay mechanism further comprises: a. a valve formed in the clutch body proximate one of the clutch body first end or second end; b. a piston operatively coupled to the shaft first end; and c. a cavity formed in the clutch body between one of the clutch body first end and the piston or the clutch body second end and the piston, wherein the cavity is in fluid communication with the atmosphere through the valve.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Having described various embodiments in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS
(13) Various embodiments will now be described more fully herein with reference to the accompanying drawings, in which various relevant embodiments are shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
(14) Overview
(15) A standard arrow rest 10 is shown in
(16) The bow 12 is generally used to shoot or fire the arrow 38. The arrow 38 has a nock or notch (not numbered) in the opposite end as the arrow head (not numbered). In other words, the arrow 38 has a notch in the end laterally behind a fletch 41 of the arrow 38. The bow string 30 is fitted into the nock. The arrow 38 is then drawn back into a firing position, away from the arrow shelf 16 and the sight window 18, providing tension in the bow string 28. When the bow string 30 is released, the tension propels the arrow 38 forward.
(17) The standard arrow rest 10, as shown in
(18) During operation of the standard arrow rest 10, the arrow rest launcher arm 44 moves from the arrow fired position into the support position when tension is let off the arrow rest cord 36. That is, the mechanism in the arrow rest 10 biases the arrow rest launcher arm into the arrow support position when an arrow 38 is drawn in the bow 12 into the firing position since the buss cable 34 moves upward releasing the tension on the arrow rest cord 36. Thus, as the buss cable 34 moves up, the tension on the arrow rest cord 36 is released allowing the arrow rest launcher arm 44 to move into the arrow support position. At the moment when the arrow 38 is fired from the bow 12, the buss cable 34 rapidly moves downward, thereby quickly exerting tension on the arrow rest cord 36 moving the arrow rest launcher arm 44 out of the flight path of the arrow 38 so that the arrow fletching 41 can pass by the arrow rest 10 without being obstructed by the arrow rest launcher arm 44.
(19) As described above, standard arrow rest designs are configured to allow the arrow rest launcher arm 44 to move into the arrow support position only when the arrow 38 is being drawn in the bow 12 into the firing position. In various embodiments of the clutch disclosed herein, the clutch is configured to allow the arrow rest launcher arm to move into the arrow support position prior to the arrow being nocked and drawn into the firing position.
(20) Referring to
(21) Arrow Rest Clutch Structure
(22) Referring to
(23) An elongated shaft 64 has a thread 66 formed on a first end 68 and an eyelet 70 formed on a second end 72. A diameter of the shaft first end 68 is larger than a diameter of the shaft second end 72 thereby forming a lip 80 at the transition point. The shaft threads 66 terminate at the lip 80 intermediate the first and second ends 68 and 72 of the shaft 64. The body threads 60 and the shaft threads 66 may be formed with any thread cross-section such as a trapezoid, a triangle, a square or any other suitable cross-section that allows the shaft 64 to rotate with respect to the body 50 without binding. The body threads 60 and the shaft threads 66 may have any thread pitch, and in various embodiments, the body and the rod are designed to have between one-half and three threads per inch. In some preferred embodiments, the shaft and the body are designed to have a thread pitch of one thread per inch. In these embodiments, the shaft 64 moves one inch laterally with respect to the body 50 each time the shaft turns one full revolution.
(24) A bushing 74, having a hole 76 formed there through, is received in the body open second end 56. The bushing may be maintained in the body opening 58 through a press fit, an adhesive, a pin, a screw, a rivet, an ultrasonic weld, or by any other suitable means that maintains the bushing in the body opening. When the bushing 74 is positioned in the body second end 56, the shaft second end 72 extends through the bushing hole 76. A spring 78 is positioned around the shaft 64 between the shaft threads 66 and the shaft second end 72. As a result, when the clutch 48 is assembled, the spring 78 is positioned intermediate the shaft lip 80 and the bushing 74.
(25) The spring 78 functions to bias the shaft first end 68 toward the body first end 52. That is, as the spring exerts pressure against the lip 80 when it is in a compressed state, the shaft 64 rotates clockwise with respect to the body 50, through the interaction of the threads, thereby causing the shaft first end 68 to move linearly toward the closed body first end 52. Furthermore, when an opposing force pulls on the shaft second end 72, the shaft rotates counterclockwise with respect to the body 50, through the interaction of the threads, thereby moving the shaft first end 68 linearly away from the closed body first end 52 as the spring 78 compresses between the lip 80 and the bushing 74.
(26) In a second embodiment of a clutch assembly 82 as shown in
(27) In this embodiment, the adjustable plug 102 is fit such that air may pass around the plug. The adjustable plug 102 may be press fit into the through bore 96, held by a fastener (e.g., a pin), or it may be threadably received therein. The spring 100 maintains the ball 98 substantially in a valve seat 104 at the bore second end 106 adjacent the bore 92. The valve seat 104 and the ball 98, while slowing the flow of air into the clutch body, do not create an airtight seal between the ambient atmosphere and the blind bore 92. A third hole 87 is formed in the body first end 86 and is configured to receive the arrow rest cord 36, as explained in greater detail below.
(28) A shaft 108 has a generally cylindrical (e.g., cylindrical) piston 110 formed on a first end 112 and an eyelet 114 formed through a second end 116. An O-ring 111 is received in a circumferential groove (not numbered) formed on an outer circumference 113 of the piston 110. The O-ring 111 may be formed from rubber, polymer, or any other suitable material that will maintain an airtight seal between the piston 110 and the inner circumference 94 of wall 88.
(29) A bushing 118, having a hole 120 formed there through, is received in the body open second end 90. The bushing may be maintained in the body open second end 90 through a press fit, an adhesive, a pin, a screw, a rivet, an ultrasonic weld, or by any other suitable means that maintains the bushing in the body opening. When the bushing 118 is positioned in the body open second end 90, the shaft second end 116 extends through the bushing hole 120. A spring 122 is positioned around the shaft 108 intermediate the piston 110 and shaft second end 116. As a result, when the clutch 82 is assembled, the spring 122 is positioned intermediate the piston 110 and the bushing 118, as shown in
(30) When the clutch 82 is assembled, the spring 122 functions to bias the piston 110 toward the body first end 86. That is, as the spring 122 exerts pressure against the piston 110, the piston 110 moves linearly toward the body first end 86 compressing any air that is located between the piston 110 and the body first end 86. As the spring 122 continues to force the piston 110 toward the body first end 86, the air pressure escapes out of the clutch body through the hole second end 106 by dislodging the ball 98 from the valve seat 104 against the bias of spring 100. The plug 102 and the design of the spring 100 may be used to regulate the rate that air may escape from the clutch body first end 86 so as to regulate the speed in which the shaft 108 moves through the clutch body 84.
(31) The clutch design shown in
(32) Once the tension on the shaft second end 116 is released, the force of the extension spring 122 biases the piston 110 back to the left toward the clutch body first end 86. As the shaft 108 and the piston 110 begin to move to the left (
(33) In a final embodiment shown in
(34) A shaft 140 has a generally cylindrical (e.g., cylindrical) piston 142 formed on a first end 144 and an eyelet 146 formed on a second end 148. An O-ring 150 is received in a circumferential groove (not numbered) formed on an outer circumference 152 of the piston 142. The seal 150 may be formed from rubber, polymer, or any other suitable material that maintains a seal between the piston 142 and the inner circumferential 134 of wall 130.
(35) A bushing 154, having a hole 156 formed there through, is received in the body open second end 132. The bushing 154 may be maintained in the body open second end 132 through a press fit, an adhesive, a pin, a screw, a rivet, an ultrasonic weld, or by any other suitable means that maintains the bushing in the body opening. When the bushing 154 is positioned in the body open second end 132, the shaft second end 148 extends through the bushing hole 156. A bushing O-ring 155 (
(36) The piston 142 divides the bore 136 into two sections—the first cavity 164 between the piston 142 and the bushing 154 and the second cavity 166 between the piston 142 and the body second end 128. The piston 142 has two through holes 160 and 162 that allow the first cavity 164 to be in fluid communication with the second cavity 166. This configuration allows fluid (not shown) that is maintained in the clutch body bore 136 to pass from one side of the piston 142 to the other. Thus, the size of the holes 160 and 162 and the design of the spring 158 determine when and how fast the piston 142 moves within the clutch body 126. That is, the larger the holes 160 and 162, the faster the fluid can move from the first cavity 164 to the second cavity 166 thereby allowing the piston to move through the clutch body. Moreover, the piston holes 160 and 162 also act as a delay mechanism since the piston will not begin to move until a sufficient amount of fluid passes through the holes into the second cavity 166. As such, the size of the holes and the viscosity of the fluid also determine the period of time that the clutch is maintained in the first position until a sufficient amount of fluid flows from the first cavity 164 into the second section 166.
(37) Exemplary Clutch Operation
(38)
(39)
(40)
(41) As the pressure builds in the second cavity 166, the fluid is forced though the piston holes 160 and 162 to the other side of the piston 142. Additionally, the lateral forces must also overcome the force exerted by spring 158. Once the piston 142 begins to move to the right in the clutch body 126, the second cavity 166 begins to expand and fill with fluid as the first cavity 164 begins to shrink. In the position shown in
(42) The viscosity of the fluid in the clutch body, the design of the spring 158, and the size of the holes 160 and 162 in the piston 142 affect the period of time of the delay that occurs prior to the clutch assembly moving from the compressed first position into the extended second position. In various embodiments, the period of time of the delay is about 0.001-0.05 seconds before the piston 142 beings to move out of the compressed first position. In some preferred embodiments, the period of time of the delay is about 0.007-0.012 seconds, and in more preferred embodiments the period of time of the delay is no longer than 0.02 seconds. However, it should be understood with reference to this disclosure that the clutch assembly 124 may be designed to accommodate any period of time of a delay depending on the design of the bow 12, the arrow rest 10 and the arrow 38.
(43) Referring to
(44) Based on the above description, the clutch assembly 124 can increase the combined length of the arrow rest cord 36 and the cord 49 connecting the arrow rest assembly and the bow (e.g., from the configuration in
(45) Exemplary Use
(46) Operation of the arrow rest and clutch assembly will now be described with reference to
(47) Referring to
(48) Referring to
(49) Referring to
(50) Second Embodiment
(51) In a second embodiment, the arrow rest 10 is connected to the bow 12 via the spring 47 without including the clutch as described above. Referring to
(52) Still referring to
CONCLUSION
(53) Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. For example, as will be understood by one skilled in the relevant field in light of this disclosure, the invention may take form in a variety of different mechanical and operational configurations. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that the modifications and other embodiments are intended to be included within the scope of the appended exemplary concepts. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for the purposes of limitation. The description of the above exemplary embodiments should teach one of skill in the art that many more alternatives exist that can facilitate movement of the arrow rest launcher arm from the fired position into the arrow support position.
(54) While the clutch operation was generally described with reference to the clutch of