Patent Application
20140299116
The field of the present invention relates to compound archery bows. In particular, a flexible cable guard for a compound archery bow is disclosed herein.
Examples of compound archery bows with cable guards are disclosed in the following references.
U.S. Pat. No. 4,834,061 entitled “Cable vibraguard” issued May 30, 1989 to Chattin;
U.S. Pat. No. 5,718,213 entitled “Swing arm cable guard” issued Feb. 17, 1998 to Gallops et al;
U.S. Pat. No. 6,152,124 entitled “Archery bow having an incrementally adjustable cable guard” issued Nov. 28, 2000 to Gallops;
U.S. Pat. No. 6,425,385 entitled “Archery bow having a swing arm cable guard with adjustably mounted cable saver” issued Jul. 30, 2002 to Gallops;
U.S. Pat. No. 6,178,958 entitled “Archery bow having a side mounted swing arm cable guard” issued Jan. 30, 2001 to Gallops;
U.S. Pat. No. 6,655,371 entitled “Archery bow having a swing arm cable guard with adjustably mounted cable saver” issued Dec. 2, 2003 to Gallops; and
U.S. Pat. No. 6,904,900 entitled “Archery bow with swing arm cable guard and fall-away arrow rest” issued Jun. 14, 2005 to Gallops.
A compound archery bow comprises a riser, first and second bow limbs, first and second pulley members, a draw cable, one or more additional cables, and a cable guard. The first and second bow limbs are attached to the riser, and the first and second pulley members are rotatably mounted on the first and second bow limbs, respectively. The draw cable is engaged with the first and second pulley members, and the additional cables are coupled to the first and second bow limbs. The bow limbs, the draw cable, and the additional cables are arranged so that pulling the draw cable to draw the bow causes (1) the pulley members to rotate and let out the draw cable, (2) each additional cable to be taken up or let out by at least one of the pulley members, and (3) the first and second bow limbs to bend toward one another. The cable guard comprises (1) an elongated, resilient, non-articulated member attached to and extending backward from the riser, and (2) a cable retainer engaged with the elongated member and with each additional cable. The cable guard is arranged with the bow at brace to retain a central portion of each additional cable displaced laterally from a shooting plane of the bow by a first cable displacement distance sufficient to enable an arrow shot by the bow to pass each additional cable substantially without interference between the additional cable and fletching of the arrow. The cable guard is arranged with the bow drawn to bend toward the shooting plane and to retain the central portion of each additional cable displaced laterally from the shooting plane by a second cable displacement distance sufficient to enable an arrow shot by the bow to pass each additional cable substantially without interference between the additional cable and a shaft of the arrow. The first cable displacement distance is larger than the second cable displacement distance. A method comprises arranging the cable guard on the compound bow. Another method comprises shooting an arrow with the compound bow having the cable guard.
Objects and advantages pertaining to a cable guard for a compound archery bow may become apparent upon referring to the exemplary embodiments illustrated in the drawings and disclosed in the following written description or appended claims.
The embodiments shown in the Figures are exemplary, and should not be construed as limiting the scope of the present disclosure or appended claims. Relative sizes, shapes, and proportions shown in the Figures may be distorted for clarity, and should not be considered to limit the scope of the present disclosure or appended claims.
For purposes of the present disclosure and appended claims, the terms “compound archery bow” or “compound bow” shall denote an archery bow that uses a levering system, usually comprising one or more cables and pulleys, to bend the limbs as the bow is drawn. Compound archery bows of various types are conventional, and include pulley members rotatably mounted on the bow limbs. Those pulley members typically engage a draw cable of the bow so that pulling the draw cable to draw the bow causes the pulley members to rotate and let out the draw cable. One or more additional cables are coupled to the bow limbs, by one of the pulley members at one end, and by the other pulley member or directly to the bow limb at the other end. The additional cables are let out or taken up (according to the specific design or arrangement of a given compound bow) by the pulley members as they rotate when the bow is drawn. The pulley members typically comprise an assembly of journaled wheels or cams arranged to engage the corresponding cables, however, other suitable arrangements (e.g., a set of posts or an eccentric cable attachment) can be employed and fall within the scope of the present disclosure or appended claims.
In some compound bows (e.g., single cam or hybrid cam bows) one or more of the additional cables can be referred to as a secondary or return cable. In most compound bows, one or more of the additional cables typically is arranged as a so-called power or bus cable that serves to pull the bow limbs toward one another as the bow is drawn, the pulley members rotate, and at least one end of the power cables is taken up by a corresponding pulley member. Tension developed as the bow is drawn and one or more power cables are taken up by corresponding pulley members causes deformation of the bow limbs and storage of potential energy therein. A portion of that potential energy is transformed into the kinetic energy of the arrow shot by the bow. Examples of compound bows include dual-cam bows, bows that employ a Binary Cam System®, hybrid-cam bows, or single-cam bows. A few examples of these various compound bow types are disclosed in the following patents, all of which are incorporated by reference as if fully set forth herein:
U.S. Pat. No. 4,686,955 entitled “Compound archery bows” issued Aug. 18, 1987 to Larson, disclosing an example of a dual-cam compound bow;
U.S. Pat. No. 5,368,006 entitled “Dual-feed single-cam compound bow” issued Nov. 29, 1994 to McPherson, disclosing an example of a single-cam compound bow;
U.S. Pat. No. 6,871,643 entitled “Eccentric elements for a compound archery bow” issued Mar. 29, 2005 to Cooper et al, disclosing an example of a hybrid-cam compound bow; and
U.S. Pat. No. 7,305,979 entitled “Dual-cam archery bow with simultaneous power cable take-up and let-out” issued Dec. 11, 2007 to Yehle, disclosing an example of a compound bow that employs a Binary Cam System®.
Whether dual cam, single cam, hybrid cam, or Binary Cam®, the additional cables typically are positioned between the draw cable and the riser, where they would interfere with the path of an arrow as the bow is first drawn and then shot. Accordingly, many compound bows conventionally include a rigid or articulated cable guard. Such a cable guard is typically attached to the riser and arranged to displace a central portion of each additional cable laterally from the bow's shooting plane (i.e., a plane substantially defined by the draw cable travel as the bow is drawn and then shot). If sufficiently displaced, the additional cables do not interfere with the shaft or fletching of an arrow as it is nocked, the bow is drawn, and the arrow is shot.
Conventional cable guards typically comprise a rigid or articulated member extending backward from the riser, and a cable retainer engaged with the member and with the additional cables to be laterally displaced. In some compound bows, the arrangement of the limbs and pulley members results in substantial fore-and-aft motion of the additional cables as the bow is drawn. The cable guard for such a bow must allow for that motion of the additional cables while displacing those cables laterally. A common solution is a cable block slidable along a rigid cable guard rod or other member extending backward from the riser. Another solution is to mount the cable block on an articulated arm that allows the block to move with the cables. In either case the cable block includes generally vertical holes or slots for receiving and retaining the additional cables while allowing one or more of them to slide through the holes or slots. In other compound bows there is little or no fore-and-aft motion. A cable block arrangement can be used for such bows. Alternatively, one or more journaled wheels can be rotatably mounted on a rigid cable guard member, with each laterally displaced cable engaged with a journal of one of the wheels.
While solving the problem of interference between the arrow and the additional cables as the bow is first drawn and then the arrow is shot, conventional cable guards introduce a different problem. Lateral displacement of the additional cables causes them to exert forces on the corresponding pulley members or bow limbs that are not parallel to the shooting plane; the forces exerted by those cables include a laterally directed component. The laterally directed force components can result in tilting of the pulley members (i.e., so-called cam lean), torquing or twisting of the bow limbs, or torquing or twisting of the riser. Those effects become more pronounced as the bow is drawn and the power cables in particular experience greater tension. Any one or more of those effects can result in undesirable wear or fatigue of the bow or its parts, or can result in degraded velocity or accuracy of the bow. It is desirable to reduce the lateral force components exerted by the laterally displaced cables. This can be accomplished by reducing the lateral displacement, but at brace the lateral displacement of the cables preferably would still enable passage of the shot arrow substantially without interference between the displaced cables and the arrow's fletching.
However, that amount of displacement is only needed when the fletching passes by the additional cables. As the bow is drawn and during the early portion of its flight (before the fletching passes the additional cables), the additional cables need only be displaced enough to clear the shaft of the arrow. Reduced lateral displacement in turn reduces the lateral force components exerted by the cables. Such reduced lateral displacement of the cables has been achieved previously by employing an articulated cable guard with its articulation axis tilted slightly, as disclosed in U.S. Pat. No. 5,718,213.
Reduced lateral force components are achieved in a compound bow according to the present disclosure and appended claims. Exemplary compound bows 10 are illustrated schematically in
The exemplary bows 10 of
Each of the exemplary bows 10 includes a cable guard 40 attached to the riser 12 and arranged to displace laterally the power cables 22. In the exemplary bow of
As shown in
As shown in
In the exemplary bow of
Likewise, the displacement of the cables 22 by the member 42 and the cable block 46 as the bow 10 of
Any suitably strong and resilient material can be used to form member 42, e.g., fiberglass or other composite, plastic or polymer, wood, or metal or alloy (such as spring steel). An elastic modulus of a suitable material for member 42 typically can be less than about 10 Mpsi (1 Mpsi≡106 pounds per square inch), preferably between about 2 Mpsi and about 7 Mpsi. In a particular example, fiberglass is employed having a modulus of about 5.6 Mpsi.
Member 42 can have any suitable cross sectional shape (e.g., circular, elliptical, oval, square, rectangular, or polygonal). It can be advantageous to employ a cross sectional shape for member 42 that is larger in a transverse dimension parallel to the shooting plane than in the orthogonal transverse dimension, to allow bending of member 42 toward the shooting plane while hindering bending toward one or the other of the bow limbs. For the exemplary cable guard of
Any suitable distances can be chosen for D1 and D2 that eliminate interference between any additional cables and the fletching or shaft, respectively, of an arrow (or reduce that interference to a substantially negligible level). D1 or D2 might typically be made as small as practicable for fletching and shaft sizes of arrows typically shot with a given bow. D1 can typically range between about 0.5 inches and about 1.0 inches, preferably between about 0.65 and about 0.85 inches. D2 can typically range between about 0.2 inches and about 0.9 inches, preferably between about 0.4 inches and about 0.6 inches. In one particular example, D1 is about 0.75 inches and D2 is about 0.5 inches.
It is intended that equivalents of the disclosed exemplary embodiments and methods shall fall within the scope of the present disclosure or appended claims. It is intended that the disclosed exemplary embodiments and methods, and equivalents thereof, may be modified while remaining within the scope of the present disclosure or appended claims.
For purposes of the present disclosure and appended claims, the conjunction “or” is to be construed inclusively (e.g., “a dog or a cat” would be interpreted as “a dog, or a cat, or both”; e.g., “a dog, a cat, or a mouse” would be interpreted as “a dog, or a cat, or a mouse, or any two, or all three”), unless: (i) it is explicitly stated otherwise, e.g., by use of “either . . . or”, “only one of . . . ”, or similar language; or (ii) two or more of the listed alternatives are mutually exclusive within the particular context, in which case “or” would encompass only those combinations involving non-mutually-exclusive alternatives. For purposes of the present disclosure or appended claims, the words “comprising,” “including,” “having,” and variants thereof shall be construed as open ended terminology, with the same meaning as if the phrase “at least” were appended after each instance thereof.
In the appended claims, if the provisions of 35 USC §112 ¶6 are desired to be invoked in an apparatus claim, then the word “means” will appear in that apparatus claim. If those provisions are desired to be invoked in a method claim, the words “a step for” will appear in that method claim. Conversely, if the words “means” or “a step for” do not appear in a claim, then the provisions of 35 USC §112 ¶6 are not intended to be invoked for that claim.
