COMPOUND BOW WITH RIGID DEFLECTING STOP
Embodiments of the present disclosure generally relate to a bow and methods thereof. In exemplary embodiments, a bow having a centrepiece may include a limb; a string; a string pulley mounted on an end portion of the limb, the string pulley for accommodating the string; a cable pulley connected to the string pulley, the cable pulley adapted to accommodate compensating cables; a subassembly mounted in a rotatable manner, the subassembly comprising the string pulley and cable pulley; and a deflecting stop adapted to limit the deflection of the string, the deflecting stop adapted to strike against a front face of the limb when the string is deflected, the deflecting stop being sufficiently rigid to stop further deflection of the string when the deflecting stop strikes against the front face of the limb.
This application is a continuation-in-part of U.S. patent application Ser. No. 13/371,574, filed Feb. 13, 2012, entitled “Compound Bow with Rigid Deflecting Stop,” and claims priority to German patent application serial no. DE102011004036.6, filed Feb. 14, 2011, the disclosures of which are incorporated by reference herein in their entireties as if fully set forth herein.
BACKGROUND1. Field of the Invention
Embodiments of the present invention relate to a bow, for example a sports or hunting bow or a crossbow.
2. Description of the Related Art
The principle common to the aforementioned pieces of sports or hunting equipment is that an archer draws a string by means of one or more elastic elements, so-called limbs, and then lets it go. The string here accelerates an arrow in the direction of a target. Modern bows or crossbows have little in common with the examples which are known from history. In particular, the variation in force when the string is drawn has, in the meantime, been adjusted optimally to the envisaged use. Therefore for example the force which has to be applied in order to draw a hunting bow in the first instance increases in relation to the deflection of the string and decreases again as the deflection of the string increases. In other words, in the first instance a comparatively large force is necessary in order to deflect the string even just by small amounts. As deflection increases, the force which acts on the archer's drawing arm decreases, and therefore a comparatively low level of force is required in order to hold the bow in its drawn position. This means that, for example in a hunting situation, the task of the archer aiming with the bow drawn is simplified to a considerable extent. This desired behaviour of the bow is achieved according to the prior art in that the string of the bow is guided on rotatable string pulleys at the ends of the limbs. Connected rigidly to the string pulleys, and thus likewise mounted in a rotatable manner, are the so-called cable pulleys, on which are guided compensating cables which serve for the symmetrical deformation of the limbs and for uniform force distribution. The geometry and method of mounting the string and cable pulleys here determine, in addition to other parameters, essentially the variation in force of the bow. The geometry of the string pulleys and of the cable pulleys can result, in particular, in the string no longer being subjected to any restoring force in the case of an excessively large amount of deflection, and therefore the drawn bow remains in its drawn state even in the cases where the archer lets go of the drawn string. This effect is also referred to by the term “cocking”. Even just a slight action or movement can result in a sudden release of drawing tension from a bow drawn in such a way. Particularly in those cases where there is no arrow placed in position, which could convert the stored energy into kinetic energy, the above described sudden release of drawing tension from the bow may result in parts of the bow, in particular the string, the limbs or even the string or cable pulleys, being destroyed. Fragments flying around here may also be hazardous to, or injure, nearby individuals.
In the case of bows with compensating cables, it should be ensured that the arrow, during acceleration, does not come into contact with a compensating cable since, otherwise, the arrow could be deflected laterally or the compensating cable could also be damaged. In the case of a so-called shoot-through bow, this problem is solved in that the arrow, during shooting, is guided through between the compensating cables. The compensating cables are arranged symmetrically in relation to the plane of the string pulleys, wherein it is also possible, at the same time, to realize a high level of symmetry for the variation in force. It is thus also possible to prevent torsion of the bow as a whole as it is drawn. This is important because the elastic torsion of the bow could be released as the arrow accelerates and have an adverse effect on the following phase of flight of the arrow.
The following text will refer to a type 1 shoot-through bow, if the ends of the compensating cables are fitted on the limbs on one side, i.e. if the first end of a compensating cable runs on a cable pulley and the other end of the compensating cable is fixed on the limb opposite. This type of bow is also referred to, inter alia, as a twin-cam bow. In the case of a type 2 shoot-through bow, the compensating cables, in contrast, are not fastened on the limb; rather, they run over the cable pulleys on both sides of the bow. This is a special embodiment of the twin-cam bow, also known as a binary-cam bow.
For the purpose of avoiding cocking, German patent DE 10 2008 063 388 discloses the practice, for shoot-through bows, of having a deflecting stop strike against a compensating cable. The disadvantage here, however, is that the rotary position of the string pulley at maximum deflection, on account of the compliance of the compensating cable against which the deflecting stop strikes, is given only in the presence of comparatively high tolerance. There is no firmly defined stop, i.e. a precise rotary position of the string pulley in relation to the limb.
SUMMARYIt is an object of the invention to provide a type 1 or 2 shoot-through bow which has robust behaviour in relation to the outlined problem of “cocking” and in the case of which the maximum deflection of the string can be adjusted in a defined manner.
This object is achieved by the bow having the features given in claim 1. The dependent claims relate to advantageous embodiments and developments of the invention.
The bow according to the invention has a centrepiece, two flexurally elastic limbs, a string and at least one string pulley, mounted in one end of a limb and intended for accommodating the string. The bow also contains at least two cable pulleys, connected to the string pulley and intended for accommodating and guiding compensating cables, wherein in each case at least one cable pulley is arranged on both sides of the string pulley, and wherein the subassembly made up of the string pulley and cable pulleys is mounted in a rotatable manner in each case, and at least one deflecting stop is present for the purpose of limiting the deflection of the string. The deflecting stop, when the string is deflected, strikes against a limb or against a stop element connected rigidly to the limb.
The advantages of the bow according to the invention are achieved by using rigid components which, in the case of an appropriate geometrical design and of an appropriate combination of components, result in adjustable and firmly defined limitation of the maximum deflection of the string.
The stop element may also be a spacer bolt connected rigidly to a limb.
The invention can be realized, in principle, using just one of the deflecting stops described. In addition, it is also conceivable to use a plurality of deflecting stops, in particular in each case one deflecting stop for the two limbs.
The deflecting stop here may be formed in one piece with the subassembly made up of the string pulley and cable pulleys or may be formed in one piece in a string pulley or a cable pulley. In addition, it is also conceivable to realize the deflecting stop as a component in more than one piece.
The deflecting stop described can advantageously be used in various compound bows or cam systems, for example binary, one and a half, solo-cam or two-cam systems and the different variants thereof.
When the string of the bow is drawn, it is possible for at least one compensating cable to run between that side of the deflecting stop on which the latter is connected to the subassembly made up of the string pulley and cable pulleys and that side of the deflecting stop which strikes against the limb or the stop element.
In other words, the deflecting stop may be configured such that it exhibits a recess into which the compensating cable can enter when the bow is drawn. The deflecting stop further exhibits an extension which, when the bow is drawn, moves past the compensating cable and strikes, by way of an end side, against a limb or a part connected rigidly to the limb. It is thus possible for the deflecting stop described to be configured, for example, in the form of a large L, wherein it has the short end of the L fastened on the subassembly made up of the string pulley and cable pulleys, and wherein the end of the long side of the L strikes against the limb or the component connected rigidly thereto. For adjustment capability of the deflecting stop, it is possible here to adjust, in particular, the length of the long side of the L. This is possible in a particularly straightforward manner, for example, in that the short side of the L has a threaded bore into which is screwed a screw—possibly secured by lock nuts—as the long side of the L. Straightforward rotation of the screw thus makes it possible to adjust the position of the deflecting stop.
Irrespective of the actual configuration of the deflecting stop, it is possible to vary the maximum deflection of the string by adjustment of the deflecting stop, in particular of the fastening position of the deflecting stop. The fastening position defines the position of the deflecting stop relative to the element on which the deflecting stop is fastened.
The maximum deflection of the string can be varied not just by the fastening position of the deflecting stop, but also by an alternative adjustment of the deflecting stop. It is thus conceivable, for example, to arrange the deflecting stop as a threaded screw in a corresponding threaded bore in the subassembly made up of the string and cable pulleys, and therefore the length of the deflecting stop can be adjusted by straightforward rotation in the thread.
As an alternative, or in addition, the maximum deflection of the string can also be varied by adjustment of the stop element.
The bow may be a twin-cam bow, i.e. a type 1 bow.
The bow may also be a binary-cam bow, i.e. a type 2 bow.
In an advantageous embodiment of the invention, the bow is a shoot-through bow with shoot-through centrepiece.
A shoot-through centrepiece is a centrepiece in the case of which the arrow, rather than being moved past the centrepiece, can be guided through an opening provided in the centrepiece itself. This gives a greater range of possibilities for configuring the centrepiece.
Since the shoot-through centrepiece is formed symmetrically in relation to a plane which is formed by the string when the bow is drawn, it is possible for the bow according to the invention to be further optimized in respect of its behaviour during shooting. The improved dynamic behaviour of the bow here can be attributed in particular to the fact that the aforementioned symmetrical configuration of the shoot-through centrepiece means that the bow is, in practice, of fully symmetrical construction. As a result, torques to which the bow could be subjected as a result of forces of inertia in particular from the limbs and the centrepiece are reduced to a considerable extent, and shooting is more stable overall. Lateral deformation of the shoot-through centrepiece under the action of the forces emanating from the drawn limbs can also be effectively reduced in this way.
The above described shoot-through centrepiece can be used in various compound bows or cam systems, for example binary, one and a half, solo-cam or two-cam systems, and the different variants thereof, with or without the deflecting stop described above.
Furthermore, it is also possible to implement additional components on the shoot-through bow. For example, additional elements can be used to position the compensating cables such that the arrow can be shot through between the compensating cables without obstruction. This is also possible, inter alia, using a cable spreader, of which the U-shaped construction gives rise to an increased spacing between the compensating cables. Furthermore, it is also possible to fit one or more string stoppers, which are in contact with the string in the undrawn state and, when the string is released, can also be used to reduce vibration. It is also possible to implement so-called reverse roller guards or reverse assist roller guards, which guide the compensating cables in a fixed position over rollers. The string stoppers and the reverse roller guards may also be realized by a composite component, wherein this may be in one or more parts, and/or may also be adjustable.
So the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of embodiments of the present disclosure, briefly summarized above, may be had by reference to embodiments, which are illustrated in the appended drawings. It is to be noted, however, the appended drawings illustrate only typical embodiments of embodiments encompassed within the scope of the present disclosure, and, therefore, are not to be considered limiting, for the present disclosure may admit to other equally effective embodiments, wherein:
The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word may is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including but not limited to.
DETAILED DESCRIPTIONThe illustration in
The string pulley 3 may be mounted in a suitable location, for example, on an end portion of the limb 2. The string pulley 3 may generally be used for accommodating the string 7 and a cable pulley 4 connected to the string pulley 3. The cable pulley 4 may be adapted to accommodate and/or guide compensating cables 8, 9. The string pulleys 3 are arranged in a rotatable manner at each of the ends of the limbs 2. A cable pulley 4 may be connected to the string pulleys 3. The string 7 may run in a first groove on the string pulley 3, whereas the compensating cables 8 and 9 may run in a second groove and third groove, respectively, on the cable pulley 4. In addition, a deflecting stop 6 may be mounted on the interconnected string and cable pulleys 3 and 4. The deflecting stop 6 may serve to limit the drawing movement of the bow. Examples of each of these elements depicted in
In exemplary embodiments, the bow may include a bearing block 5. The bearing block 5 may generally function to raise and/or position a pivot point of the subassembly comprising the string pulley 3 and the cable pulley 4, or the like, such the deflecting stop 6 may be in position to strike a front face of the limb 2 when the string 7 is deflected, thereby preventing further deflection of the string 7. The bearing block 5 may comprise a substantially rigid element with an opening for receiving the cable, or the like. The bearing block 5 may be attached to a suitable portion of the limb 2, for example, an end portion of the limb 2. In some embodiments, the bearing block 5 may comprise a square base with a substantially triangular top portion, or the like.
In exemplary embodiments, the bow may also comprise a second deflecting stop 12 adapted to hit a cable. In some embodiments, the second deflecting stop 12 may be attached to the cable pulley 4, the string pulley 3, the bearing block 5, and/or the like. For example, the second deflecting stop 12 may extend from a portion of the cable pulley 4. In some embodiments, the bow may comprise one or both of the deflecting stop 6 and the second deflecting stop 12. In some embodiments, the first deflecting stop 6 and the second deflecting stop 12 may strike the limb 2 and a cable, respectively, at substantially the same time or at exactly the same time. In some embodiments one of the deflecting stops 6, 12, may strike before the other and the deflecting stop 6, 12 that does not strike first may be included as a backup in case the deflecting stop 6, 12 that strikes first fails. The deflecting stops 6, 12 may be used to stop further deflection of the string 7 when the string 7 is drawn to a certain point. In some embodiments, if a deflecting stop 6 is not present, the second deflecting stop 12 may stop further deflection of the string 7 when striking a cable 8, 9, or the like.
In some embodiments, the slotted hole 10 may allow the deflecting stop 6 to slide in a first direction that would restrict the deflection of the string 7 to a predetermined amount and allow the deflecting stop 6 to slide in a second direction that would increases the amount of deflection of the string 7 before the deflecting stop 6 hits the limb 2 and stops further deflection of the string 7. In some embodiments, the deflecting stop 6 may be secured in a position within the slotted hole 10 by use of a tightening mechanism, such as a screw tightening device, a snap, and/or the like. In some embodiments, the slotted hole 10 may comprise a shape suitable for embodiments of the present disclosure, for example, a curved or crescent shape, or the like. In some embodiments, the slotted hole may be positioned in a suitable position in the string pulley 3, or the like.
In some embodiments, the limb 2 may comprise a front face 11 positioned on a distal end of the limb 2 substantially opposite the centerpiece 1, or the like. In some embodiments, the front face 11 of the limb 2 may be sufficiently rigid such that when the deflecting stop 6 strikes the front face 11 of the limb, further deflection of the string 7 is prevented. In some embodiments, the front face 11 of the limb 2 may be shaped to stop the deflecting stop 6, or the like. For example the front face 11 of the limb 2 may be flat or curved to accept the deflecting stop 6, or the like.
The inventive concepts described can also be used analogously for all compound bows in which the compensating cables, as a result of additional guide elements, are deflected asymmetrically, in relation to a plane formed by the string and the centrepiece of the bow, onto one side of the bow, and the arrow can thus be moved past the compensating cables during shooting, and for a crossbow or the like. It is thus intended for the term “bow” used in the present application also to cover the configuration of the apparatus according to the invention as a crossbow or a plaything, or a piece of sports and/or hunting equipment, which accelerates arrows, balls, bolts or the like.
It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the disclosure. Many variations and modifications may be made to the above-described embodiment(s) of the disclosure without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present disclosure and protected by the following claims.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. For example, although numerous embodiments having various features have been described herein, combinations of such various features in other combinations not discussed herein are contemplated within the scope of embodiments of the present invention.
Claims
1. A bow having a centrepiece, comprising:
- a limb;
- a string;
- a string pulley mounted on an end portion of the limb, the string pulley for accommodating the string;
- a cable pulley connected to the string pulley, the cable pulley adapted to accommodate a cable;
- a subassembly mounted in a rotatable manner, the subassembly comprising the string pulley and cable pulley; and
- a deflecting stop adapted to limit the deflection of the string, the deflecting stop adapted to strike against a front face of the limb when the string is deflected, the deflecting stop being sufficiently rigid to stop further deflection of the string when the deflecting stop strikes against the front face of the limb.
2. The bow of claim 1, further comprising a slotted hole adapted to allow adjustment of the deflecting stop.
3. The bow as set forth in claim 2, wherein a maximum deflection of the string can be varied by adjustment of the deflecting stop within the slotted hole.
4. The bow of claim 2, wherein the slotted hole is curved.
5. The bow of claim 1, further comprising a bearing block for setting the pivot point of the subassembly at a position away from the limb.
6. The bow of claim 5, wherein the bearing block is attached to the limb.
7. The bow of claim 1, further comprising a second deflecting stop adapted to limit the deflection of the string, the second deflecting stop adapted to strike against a cable when the string is deflected.
8. The bow of claim 7, wherein the second deflecting stop extends from a portion of the subassembly.
9. The bow of claim 7, wherein the deflecting stop is adapted to strike the front face of the limb at substantially the same time that the second deflecting stop strikes the cable.
10. The bow as set forth in claim 1, wherein the bow is a binary-cam bow.
11. The bow as set forth in claim 1, wherein the bow is a shoot-through bow with shoot-through centrepiece.
12. The bow according to claim 1, wherein the shoot-through centrepiece is formed symmetrically in relation to a plane which is formed by the string when the bow is drawn.
Type: Application
Filed: Jan 5, 2015
Publication Date: May 21, 2015
Inventor: CHRISTOPH OKUPNIAK (Aalen)
Application Number: 14/589,983