Patent Grant
6968834
This invention relates to archery bows, and more particularly to apparatuses, commonly known as bow presses, that are used for installing, replacing, or adjustment of a bow string or components of archery bows.
Compound bows are widely used by archers. The popularity of the compound bow is mainly due to the advantage provided in the reduced pull force required at full draw together with the resulting increase in accuracy. The pull on the bow string is high at the beginning of the draw but the archer at this point is able to exert maximum force. As the draw progresses a little beyond mid-point, there is an over-center action on eccentrically mounted pulleys or cams of the compound bow which decreases the draw force needed to maintain the bow string in the drawn position while maximizing the energy stored in the limbs of the bow. Thus, at full draw it is relatively easy to hold the arrow and bow string and much easier to perfect aiming technique and proper release resulting in increased accuracy.
A typical compound bow includes one or more eccentrically mounted pulleys or cams pivotably attached relative the bow limbs and serving to support and control the movement of a bow string. The cam, in turn, is often connected to a tension cable. The stringing or tuning of a twin cam bow, with its eccentrically mounted pulleys, tension cable and bow string is very critical in order to achieve a proper balance or synchronization of the eccentrically mounted pulleys or cams. The complexity of the stringing and the sensitivity to proper tuning of the bow, makes it undesirable to unstring the bow when it is not in use. It is also a major project, and in some cases impossible, to string and tune such a bow without the aid of an apparatus commonly known as a bow press.
Because a compound bow cannot be conveniently unstrung and restrung, they are virtually always left in a strung condition. However periodic retuning of compound bows is often required to maintain desired performance levels, and to change, replace or repair components of the compound bow, such as the bow string, string sights, dampers, the tension cable, the cams and other components.
Through the years a number of bow presses have been developed for facilitating stringing, tuning, and maintenance of compound bows. In general, these presses have included a stationary base having a pair of spaced apart inside surface supports, in the form of pegs or rollers, for contacting the inside of the bow, and a pair of limb supports, in the form of pegs or rollers, attached to a movable mechanism for applying a bending force the limbs of the bow. Several problems have been noted with regard to prior bow presses, however.
Prior bow presses can damage the bow, particularly when operated by inexperienced personnel. It is very important that the inside surface support and the limb supports of the bow press be precisely positioned in such a manner that the bow is properly loaded into the press in such a manner that the limbs are bent in a way that will not overstress or otherwise damage the bow. Because compound bows vary dimensionally, from one model or manufacturer to another, it is necessary that the inside surface support and the limb supports on the bow press be adjustable. In the past, it has been customary to provide incremental holes in the bow press so that the position of the inside surface support and the limb supports, or other components of the bow press, could be moved to achieve a best fit with regard to a given bow. The incremental nature of this adjustment approach often results in a fit of the bow press to the bow which is not quite ideal, and can result in damage to the bow. This is especially problematic where personnel operating the bow press lack experience and knowledge.
It is also generally necessary that the bow press be adjusted in a manner that results in a symmetrical positioning of the inside surface supports and the limb supports with respect to the center of the bow handle. Prior bow presses do not provide a convenient means of achieving this symmetry.
Prior bow presses are also not easy to adjust, in that the incrementally movable components are typically bolted to the bow press, thereby requiring the use of wrenches or other tools for making the necessary adjustments.
The limbs of the bow can also be damaged, even when the bow press is properly adjusted, by prior bow presses which use limb supports that must slide or roll along the limb as it is bent in the bow press. Such rolling or sliding supports can cause marring and other physical damage to the limbs.
In some prior bow presses, it is also possible, under some conditions, for the limb supports to be moved to a position along the limbs where the bow will become locked into the bow press. This typically results in significant damage to the bow, and can create a potentially hazardous condition for personnel operating the bow press, as they attempt to remove the bow from the press. In such situations, it may even be necessary to partly disassemble the bow press to get the bow out of the press. The bow limbs will have considerable energy stored in them, which could cause them to spring outward dangerously when parts of bow press are removed to release the bow from the press.
It is desirable, therefore, to provide an improved bow press apparatus and method which overcomes one or more of the problems described above, or other problems and shortcomings of prior bow presses.
The invention provides an improved apparatus and method for deflecting the limbs of an archery bow to allow installation, replacement, or adjustment of a bow string or components of the bow, where the bow includes a bow handle and two limbs extending in opposite directions from the bow handle, with each limb including provisions at a distal end thereof for attaching the string.
In one form of the invention, a bow press includes a base, first and second pivot arms, and an adjustment apparatus operatively connecting the first and second pivot arms to the base. The base defines a longitudinal axis of the base, and is adapted for retaining the bow handle. The first pivot arm is adapted for applying a bending force against one of the limbs of the bow, and the second pivot arm is adapted for applying a bending force against the other limb of the bow. The first and second pivot arms are spaced from one another along the longitudinal axis of the base, with each of the first and second pivot arms having a pivoted end and a distal end thereof. The pivoted end of each pivot arm is operatively attached by the adjustment apparatus, to the base, for pivoting motion about a respective pivot axis of that pivot arm, in a manner that constrains the distal end of that pivot arm to circumscribe an arc extending generally parallel to a plane including the longitudinal axis of the base. The first and second pivot arms are also operatively and symmetrically attached to the base on opposite sides of a second axis extending orthogonally through the longitudinal axis of the base within the plane including the longitudinal axis of the base. The adjustment apparatus provides simultaneous selective movement of the first and second pivot arms along the longitudinal axis, toward or away from the second axis, while continually maintaining the symmetrical relationship of the pivoted ends of the first and second pivot arms to the second axis.
In another form of the invention, a bow press includes a base, first and second inside surface supports, a first and a second pivot arm, a first and a second limb support, and an adjustment apparatus. The base defines a longitudinal axis of the base. The first and second inside surface supports are adapted for retaining the bow handle during use of the bow press. The inside surface supports are operatively attached to the base in a manner providing infinitely adjustable movement relative to one another along the longitudinal axis of the base over a predetermined range of inside surface support positions. The first pivot arm is adapted for applying a bending force against a first limb of the bow, and the second pivot arm is adapted for applying a bending force against the second limb of the bow. The adjustment apparatus operatively connects the first and second pivot arms to the base.
The first limb support may be slidingly attached to the first pivot arm and adapted for contacting an outside surface of the first limb at a point along the first limb adjacent the distal end of the first limb. The second limb support may be slidingly attached to the second pivot arm and adapted for contacting an outside surface of the second limb at a point along the second limb adjacent the distal end of the second limb. The first and second limb supports may be operatively attached to the first and second pivot arms respectively for infinitely adjustable movement along the first or second pivot arm respectively, within a range of adjustment of the first and second limb supports, to thereby allow the first and second limb supports to be positioned respectively adjacent the distal ends of the first and second limbs of the bow.
In another form of the invention, a bow press includes a base, a pivot arm operatively connected to the base by a pivot arm bracket, and an inside surface support. The base defines a longitudinal axis of the base, and a second axis extending through the base orthogonally through the longitudinal axis. The longitudinal axis of the base and the second axis define a plane including both the longitudinal axis of the base and the second axis. The pivot arm is adapted for applying a bending force against one of the limbs of a bow. The pivot arm bracket operatively connects the pivot arm to the base, and defines a pivot axis. The inside surface support is adapted for contacting an inside surface of the bow at a first point along the bow. The pivot arm has a pivoted end and a distal end thereof, with the pivoted end being pivotably attached to the pivot arm bracket for pivoting motion of the pivot arm about a pivot axis in a manner that constrains the distal end the pivot arm to circumscribe an arc extending generally parallel to the plane including the longitudinal axis of the base. The inside surface support is attached to the pivot arm bracket at a point inboard of the first pivot axis, with respect to the second axis, and extends generally transversely outward from the pivot arm bracket, with respect to the plane containing both the first longitudinal axis and the second axis, with the spacing between the inside surface support and the pivot axis being fixed at a predetermined distance. The inside surface support may also be disposed in close proximity to the pivot point at a location that is farther away from the longitudinal axis than the pivot point.
Other aspects, objectives and advantages of the invention will be apparent from the following detailed description and the accompanying drawings.
While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims.
As shown in
The first and second pivot arms 28, 30 are spaced from one another along the longitudinal axis 34 of the base 26, with each of the first and second pivot arms 28, 30 having a pivoted end 38 and a distal end 40 thereof, as shown in
The first and second pivot arms 28, 30 are also operatively and symmetrically attached to the base 26 on opposite sides of a second axis 50 extending orthogonally through the longitudinal axis 34 of the base 26, within the plane 48 including the longitudinal axis 34 of the base 26. The adjustment apparatus 32 provides simultaneous selective movement, in the manner described below, of the first and second pivot arms 28, 30 along the longitudinal axis 34, toward or away from the second axis 50, while continually maintaining the symmetrical relationship of the pivoted ends 38 of the first and second pivot arms 28, 30 to the second axis 50.
The bow press 10 further includes a first pivot arm bracket 56 for operatively connecting the pivoted end 38 of the first pivot arm 28 to the base 26, and a second pivot arm bracket 58 for operatively connecting the pivoted end 38 of the second pivot arm 30 to the base 26. As will be appreciated from the drawings, the pivot arm brackets 26, 58 are slidingly attached to the base 16 in such a manner that the first and second pivot arms 28, 30 are operatively connected to the base 26 and one another for sliding movement along the longitudinal axis 34 of the base 16.
The adjustment apparatus 32 includes a bracket positioning apparatus, generally indicated at reference numeral 60 in
As best seen in
The bracket positioning apparatus 60 of the exemplary embodiment of the bow press 10 also includes a pair of locking devices, in the form of a pivot arm bracket hand screw 76 operatively attached to each of the first and second pivot arm brackets 56, 58, for selectively securing the first and second pivot arm brackets 56, 58 to the base 26, to thereby restrain the first and second pivot brackets 56, 58 against movement with respect to the base 26.
It will be recognized, however, that in other embodiments of the invention, different types of apparatuses may be utilized for performing the functions provided by the endless belt 62, pulleys 64 and 74, and the hand screws 76 of the exemplary embodiment of the bracket positioning apparatus 60 described above. For example,
In the alternate embodiment of the bracket positioning apparatus 60, shown in
The exemplary embodiment of the bow press 10 includes a first inside surface support 78, adapted for contacting an inside surface 80 of the bow handle 20 and/or the first limb 12 at a first point 82 along the bow 16, that is closely adjacent to the intersection of the bow handle 20 and the first limb 12. Whether the first inside surface support 78 contacts the inside surfaces of both the bow handle 20 and the first limb 12, at the first contact point 82, as shown in
The first inside surface support 78 is attached to the first pivot arm bracket 56 at a point located inboard of the first pivot axis 42, with respect to the second axis 50, at a fixed distance from the first pivot axis 42, and extends generally transversely outward from the first pivot arm bracket 56 in a first direction (out of the page as depicted in
In similar fashion, the exemplary embodiment of the bow press 10 includes a second inside surface support 84, adapted for contacting the inside surface 80 of the bow handle 20 and/or the second limb 14 at a second point 86 along the bow 16, that is closely adjacent to the intersection of the bow handle 20 and the second limb 14. Whether the first second inside surface support 84 contacts the inside surfaces of both the bow handle 20 and the second limb 14, at the second contact point 86, as shown in
The second inside surface support 84 is attached to the second pivot arm bracket 58 at a point located inboard of the second pivot axis 44, with respect to the second axis 50, at a fixed distance from the second pivot axis 44, and extends generally transversely outward from the second pivot arm bracket 58 in a first direction (out of the page as depicted in
The exemplary embodiment of the bow press 10 further includes a first limb support bracket 88 slidingly attached to the first pivot arm 28, and having a first limb support 90 extending generally transversely outward from the first limb support bracket 88 in the first direction (out of the page as shown in
In similar fashion, a second limb support bracket 96 is slidingly attached to the second pivot arm 30 and includes a second limb support 98 extending generally transversely outward from the second limb support bracket 96 in the first direction (out of the page as shown in
The exemplary embodiment of the bow press 10 further includes an actuation apparatus, generally indicated at 104 in
The first and second links 108, 110 each have a first end thereof pivotably attached respectively to the first and second pivot arms 28, 30. In the exemplary embodiment, the links 108, 110 are attached to the first and second limb support brackets 88, 96 to pivot about the centerlines of the first and second limb supports 90, 98, but in other embodiments of the invention, other pivoting connection arrangements may be used between the links 108, 110 and the pivot arms 28, 30 The first and second links 108, 110 intersect and are pivotably joined to one another at the intersection by a common connection, in the form of a pin 116 extending outward from the extensible section 113 of the screw jack 106.
By virtue of the mounting arrangement of the screw jack 106, and other components of the exemplary embodiment of the bow press 10, as described above, the pin 116 intersects and moves generally along the second axis 50 such that the common connection lies generally along the second axis 50, and the first and second links 108, 110 have equal lengths between their respective first ends, at the first and second limb supports 90, 98, and the common connection provided by the pin 116. The screw jack 106 functions as an extensible force applying element operatively disposed between the base 26 and the common connection at the pin 116, for applying bending force to the limbs 12, 14 of a bow 16 mounted in the bow press 10.
Operation of the exemplary embodiment of the bow press 10 is illustrated in
The intersection point between the first and second links 108, 100 may also be adjusted, if necessary, by placing a different hole in the links 108, 110 over the pin 116, to allow entry of the bow 16 into the bow press 10. Adjacent holes in the links 108, 110 are laterally offset from one another to aid in visually connecting the links 108, 110 to the pin 116 in such a manner that the links 108, 110 have equal lengths between their respective first ends, at the first and second limb supports 90, 98, and the common connection provided by the pin 116.
The hand screws 76 on the first and second pivot arm brackets 56, 58 are loosened, if necessary, to allow the first and second pivot arm brackets 56, 58 to be moved along the longitudinal axis 34 of the base 26, for placing the first and second inside surface supports 78, 84 in a proper position along the inside 80 of the bow 16 to contact the inside surface 80 of the bow 16 at points 82, 86 closely adjacent to where the first and second limbs 12, 14, respectively, join the handle 20.
By virtue of the construction of the exemplary embodiment of the bow press 10, as described above, the position of the first and second pivot arm brackets 56, 58 along the longitudinal axis 34 is infinitely adjustable, and not limited to set increments defined by spaced bolt holes, as was the case in prior bow presses, to thereby allow for very precise and proper positioning of the location of the inside surface supports 78, 84 to match the bow 16. Also, by virtue of the unique function of the adjustment apparatus 32 of the exemplary embodiment, as either of the first or second pivot arm brackets 56, 58 is moved along the longitudinal axis 34, the other pivot arm bracket (56 or 58) moves an equal distance in the opposite direction along the longitudinal axis 34, so that the first and second handle supports 78, 84, and the pivot axes 42, 44 are always maintained at symmetrical locations with respect to the second axis 50, regardless of where either of the pivot arm brackets 56, 58 is positioned along the longitudinal axis 34.
Having the adjustment apparatus 32 available to facilitate movement and maintaining symmetrical location of the pivot arm brackets 56, 58 provides a considerable advantage in that the bow 16 can be held in position by one hand of a person operating the bow press, while the other hand is being used to move one or the other of the pivot arm brackets 56, 58 into position along the longitudinal axis 34.
Once the inside surface supports 78, 84 are properly positioned, the hand screws 76 on the pivot arm brackets 56, 58 are tightened to lock the pivot arm brackets 56, 58 in place along the longitudinal axis 34.
The positions of the first and second limb supports 90, 98 are then adjusted, by loosening the hand screws 94, 102, and sliding the limb support brackets 88, 96 along the first and second pivot arms 28, 30, to position the limb supports 90, 98 close to the string attachment provisions 24 at the distal ends of the limbs 12, 14, and the hand screws 94, 102 are tightened to lock the limb support brackets 88, 96 in the desired locations on the first and second pivot arms 28, 30.
If necessary, the common connection point of the links 108, 110 with the pin 116 can then be adjusted to provide sufficient stroke of the extensible section 113 of the screw jack 106 for bending the bow 16 sufficiently for performing whatever repair or adjustment is required. The crank 115 is then turned to extend the jack 106 for bending the bow 16, in the manner shown in
Those having skill in the art will recognize that a bow press, in accordance with the invention, provides significant advantages that greatly facilitate repair and adjustment of compound bows. In particular, it will be noted that the pivoting arm construction and other features of the invention provide a bow press that is easier to operate and more fool-proof than prior bow presses. A bow press, according to the invention, when properly adjusted and operated will virtually eliminate the problem experienced in some prior bow presses of having a bow be improperly bent in such a manner that the bow will lock itself into the bow press and cannot be readily removed, even if bending force is removed. In the present invention, such a locked-in condition is almost impossible to achieve, and in the event that it were to occur through improper operation of the bow press, the pivoting arms and other features of the invention will allow bending pressure to be released from the limbs, so that the bow can be safely removed from the bow press.
Those having skill in the art will also recognize that, although the invention has been described herein with reference to several exemplary embodiments, many other embodiments of the invention are possible. For example, the manually operable screw jack of the exemplary embodiment may be replaced by other types of extensible force generating elements.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventor for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventor intends for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
| Number | Name | Date | Kind |
|---|---|---|---|
| 5022377 | Stevens | Jun 1991 | A |
| 5222473 | Lint | Jun 1993 | A |
| 5370103 | Desselle | Dec 1994 | A |
| 5433186 | Corwin | Jul 1995 | A |
| 6386190 | Kurtz, Jr. | May 2002 | B1 |
