ARCHERY BOW STRUCTURES

Abstract

The present disclosure is directed to archery bow and limb pocket structures and assemblies. Some archery bows include a limb arrangement with the limbs extending into limb pockets. In certain embodiments herein, the butt ends of the limbs are offset rearward of the limb bolts. In selected embodiments, the structure of the riser supports the limb pocket in a “tripod” stance having a single forward connection portion and two spaced apart rearward connections.

Description

FIELD OF THE INVENTION

The present disclosure relates generally to archery bows and more particularly pertains to improved archery bow riser and limb pocket structures and assemblies.

BACKGROUND OF THE INVENTION

Compound archery bows generally include a bow frame having a riser and two bow limbs (or four “quad” bow limbs), plus a cable system on the frame mounted to at least two rotational members such as cams or pulleys. Archery bow limbs store energy when the archer draws the bowstring. When the bowstring is drawn, the pre-stressed bow limbs, which are typically made of resilient material, are further flexed to store additional energy. When the bowstring is released, the stored energy propels the arrow. In conventional compound bows, each limb is typically formed of a single element with a substantially rectangular cross-section, where one end is attached to the bow handle and the other end has a limb tip slot formed therein, in which a rotational member such as a wheel, cam or pulley is mounted. In “quad” compound archery bows, two pairs of parallel bow limbs are used, each having one end attached to the bow handle or riser and the other end coupled with the rotational member.

It is important for the limbs to be properly aligned with the riser and securely mounted to the riser to prevent movement of the limb ends and to minimize twist or torque applied to the riser. In certain archery bows, the ends or butt sections of the limbs are received and secured in limb pockets attached to ends of the riser. Typically, limbs extend from the rear and forward along the entire length of the limb pocket, terminating adjacent the forward edge of the limb pocket and riser, abutting the inside surface of a limb pocket sidewall and liner. A limb bolt securing the limb pocket to the riser is typically arranged between the limb ends or through a slot in a limb end, with the limb butt section extending forward past the limb bolt.

Typical compound riser arrangements extend vertically as planar portions with a substantially rectangular cross-section, i.e. with a horizontal width less than the front-to-rear length. The riser planar portions can be considered as solid and without holes from a front-to-rear perspective. In other words, they do not have front-to-rear passages extending through the riser. At most, selected shoot-through bow arrangements may have spaced apart sidewalls only within a sight window portion. Accordingly, all of the forces applied to the riser by the limb pockets and transmitted along the height of the riser are concentrated and carried by the planar vertical portions.

There is a need for improved archery bow structures.

SUMMARY

The present disclosure is directed to archery bow and limb pocket structures and assemblies. A compound archery bow as shown includes a riser portion with an upper end and a lower end, with bow limbs attached to and extending from the riser, each limb having a butt, tip and hinge section. The archery bow includes a pair of limb pockets arranged at opposing ends of the riser portion and secured in part by limb bolts. In certain embodiments, the bow includes a split limb arrangement with pairs of parallel limbs with each pair extending into a limb pocket. The ends of the limbs are offset rearward of the limb bolts yet locked in place by the structure of the limb pockets. A limb pocket cover extends from the limb bolt to cover the limb ends, and force is transmitted through the cover.

In certain embodiments, the structure of the riser supports the limb pocket in a “tripod” stance having a single forward connection portion and two spaced apart rearward connections. This tripod stance helps create a stable platform that resists riser flex.

In certain embodiments, the riser is formed with a substantially open framework with additional openings and front-to-rear passages both above and below the sight window. As illustrated, an open framework of struts forms spaced apart sidewalls continued along the majority of the height of the riser. Advantages of the open framework include spacing the bracing structure more widely, providing better stability and reducing potential torque or flex of the riser, reduced mass and greater visibility.

Other objects and attendant advantages of this disclosure will be readily appreciated as the same become more clearly understood by references to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a compound archery bow according to one preferred embodiment of the present invention.

FIG. 2 is a side view of the embodiment of FIG. 1.

FIG. 3 is a rear view of the embodiment of FIG. 1.

FIG. 4 is a perspective front view of a limb pocket assembly of the embodiment of FIG. 1

FIG. 5 is a perspective rear view of a limb pocket assembly of FIG. 4

FIG. 6 is an exploded view of a limb pocket assembly of FIG. 4.

FIG. 7 is a partial side view of the limb pocket assembly of FIG. 4.

FIG. 8A is a perspective front view of a limb pocket piece usable in the limb pocket assembly of FIG. 4.

FIG. 8B is a perspective rear view of the limb pocket piece of FIG. 8A.

FIG. 9 is a perspective view of a riser structure of the embodiment of FIG. 1

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations, modifications, and further applications of the principles of the disclosure being contemplated as would normally occur to one skilled in the art to which the disclosure relates.

The present disclosure is directed to archery bow and limb pocket structures and assemblies. A compound archery bow comprises a riser portion defining a height with an upper end and a lower end, with bow limbs attached to and extending from the riser, each limb having a butt, tip and hinge section. An archery bow often includes a pair of limb pockets arranged at the upper and lower ends of the riser portion and configured to receive the butt sections of the limbs. In certain illustrated embodiments, the bow includes a split or quad limb arrangement with two pairs of limbs. The limbs extend into the limb pocket and terminate before extending to the plane with the limb bolt. In other words, the ends of the limb pieces are offset rearward of the limb bolt yet locked in place by the structure of the limb pocket. The limb pocket core and cover extends from the limb bolt to cover the limb ends, and force is transmitted through the core and cover. This allows the limbs to bend more and also allows for smaller loads to be translated to the riser.

In certain embodiments, the structure of the riser supports the limb pocket in a “tripod” stance having a single forward connection portion and two spaced apart rearward connections. This tripod stance helps create a stable platform that resists riser flex during use.

FIGS. 1-3 illustrate a representative example of a dual-cam compound archery bow generally designated as 10. When considered from the perspective of an archer holding the bow 10, it includes a riser 20 with a sight and arrow window 26 and a handle portion 28. The riser 20 includes upper end 22 and lower end 24. At least a pair of bow limbs extend from the opposing ends of the riser. As illustrated, a pair of upper limbs 32 extend rearward from an upper limb pocket assembly 50, and a pair of lower limbs 34 extend from a lower limb pocket assembly 50. This two pair arrangement is sometimes referred to as “quad limbs.” Upper limb pocket assembly 50 and lower limb pocket assembly 50 are mirror images of each other in bow 10. Upper limb assembly 50 is discussed in further detail herein. The same disclosure applies to lower limb pocket assembly 50.

Rotational members such as eccentric cams 36 and 38 are supported at the rearward limb tip sections for rotary movement about respective axles. In the embodiment shown, the upper cam 36 is carried in a gap between the outer limb tip portions of upper limbs 32. The lower cam 38 is carried in a gap between the outer limb tip portions of lower limbs 34. In a solid limb arrangement, the outer limb tip end may define a slot to carry the rotational member.

Bowstring 40 includes an upper end and a lower end which either are anchored to the cams or received in corresponding tracks defined by cams 36 and 38, depending on the arrangement. Additional cabling such as a return cable portion and a control cable portion are typically included, but are omitted herein for ease of illustrating bow 10. When the bowstring 40 is drawn, it causes eccentric cams 36 and 38 at each end of the bow to rotate, feeding out cable and bending limbs 32 and 34 inward, causing additional energy to be stored therein. When the bowstring 40 is released with an arrow engaged to the bowstring, the limbs 32 and 34 return to their rest position, causing the eccentric pulleys 36 and 38 to rotate in the opposite direction, to take up the bowstring 40 and launch the arrow with an amount of energy proportional to the energy stored in the bow limbs. Bow 10 is described for illustration and context and is not intended to be limiting. Aspects of the present disclosure can be used with dual-cam compound bows as illustrated or can be used with single-cam bows as described for example in U.S. Pat. No. 5,368,006 to McPherson. Alternately, aspects of the present disclosure can be used in other types of bows such as recurve bows or crossbows. The cams, pulleys and cabling of the bow may be conventional.

Bow 10 is illustrated with a shoot through riser 20. Riser 20 includes a sight and arrow window 26 arranged above handle 28. Window 26 defines a passage passing front-to-rear through riser 20. Window 26 is illustrated with a substantially oval cross-section, although the shape can be defined as desired. The central vertical axis of sight window 26 is aligned with a central vertical axis A of bow 10, as viewed from a front or rear perspective. The axis of bowstring 40 is also aligned with axis A. As desired, selected archery bow accessories such as an arrow rest or bow sight can be mounted and arranged within window 26. The central axis of the arrow rest and sight may also be aligned with axis A. Other accessories, such as a cable guard or a dampener, can also be mounted within or adjacent to window 26. In use an archer places an arrow through the window and on the arrow rest, and the arrow passes through window 26 when it is released. Desirably, the arrow shaft axis intersects and is perpendicular to axis A. In alternate embodiments, certain features such as the limb pocket assembly illustrated herein can be used with different riser structures, such as a riser with a left or right handed arrow shelf.

Close-up views of limb pocket assembly 50 are illustrated in FIGS. 4-5, with an exploded view in FIG. 6. A geometric view of the upper riser end 22, upper limbs 32 and limb bolt 52 is illustrated in FIG. 7, with various elements omitted for illustration purposes. FIGS. 8A and 8B illustrate limb pocket piece 150.

The limb pocket assembly 50 is mounted to the upper end 22 of riser 20 and secures the forward or butt ends 134 of limbs 32 to riser 20. Limb pocket piece 150 includes a body or core section 152. As assembled, lower surface 153 of pocket piece 150 is placed adjacent to and typically abuts limb pocket surface 23 defined by riser upper end 22. Core section 152 defines a forward end 154 and a rearward end 162. A limb bolt mounting recess 155 is defined adjacent forward end 154. Limb bolt 52 and rocker 54 may be placed into and through the limb bolt mounting recess and a corresponding limb bolt opening in limb pocket surface 23. The inward end of limb bolt 54 is fastened to the riser end, for instance it may be threadably engaged with a limb bolt barrel nut 56 arranged in riser end 22.

A pair of limb end cavities 156 are defined by limb pocket piece 150 and spaced rearward of recess 155. The limb end cavities 156 define rearward openings and extend forward along body section 152 underneath a pair of covers or top wall portions 157 extending laterally from body section 152. The downward facing surfaces 159 of covers 157 are arranged to abut the upper facing surfaces of limb ends 134. The forward depth of cavities 156 is defined by stop walls 158 facing rearward. Stop walls 158 are arranged to abut the forward end faces 135 of limbs 32. Stop walls 158 are arranged rearward of limb bolt 52. The lower side of each cavity may define an opening such that the lower side of the limb butt end is not engaged by the cavity.

As geometrically illustrated in FIG. 7, as assembled the axis B of limb bolt 52 is spaced forward by gap G from a plane or axis F defined by the limb forward faces 135. Consequently, the limb ends 134 are spaced rearward of limb bolt 52. Axis B is substantially parallel to and/or close to parallel to axis F within the limb pocket assembly.

Core section 152 defines an inner sidewall of each cavity 156. An outer side wall or portion may be defined adjacent an outer sidewall of each limb end. As illustrated in FIG. 8B, the outer sidewall portion is shown as a downward extending tab or flange. Wings 164, which are spaced rearward of the cavities, support the lower limb sides. The limb ends are engaged by the cavities on the top, inside and outside sides plus the end face, and separately engaged by the wings on a lower face to lock the limb end within the limb pocket assembly.

As limbs 32 extend rearward from cavities 156, the limbs pass over a pair of lateral wings 164 extending from the rearward end 162 of pocket piece 150. Upper surfaces 166 of wings 164 abut lower surfaces of limbs 32. Wings 164 abut the limb hinge sections and define fulcrum points for the limbs.

In the illustrated embodiment, a pair of sideplates 58 are used in conjunction with the limb pocket piece to lock the limb ends 134 within the limb pocket assembly 50. The side plates also help secure the limb pocket assembly to the riser. Each sideplate 58 includes a downward extending sidewall portion which is arranged adjacent an outer sidewall of the limb end. Each sideplate 58 also includes an upper lateral portion extending from the side plate to an anchor position between the limbs. The upper lateral portion abuts an upper face of a limb. Each sideplate 58 can be secured to the limb pocket piece 150 and the riser end 22 with fasteners, such as threaded screws. In the illustrated embodiment, each sideplate 58 is secured with three fasteners arranged adjacent a forward side portion of the limb pocket piece, a rearward side portion of the limb pocket piece and a top face of the limb pocket piece. The rearward fasteners may also fasten the rearward end 162 of the limb pocket piece to riser end 22.

In use as assembled, the gap G between limbs ends 134 and limb bolt 52 is bridged and filled by the limb pocket covers 157 and body portion 152. When limbs 32 are flexed as bow 10 is drawn, the butt ends 134 and the limb pocket piece 150 are urged to pivot upward around the fulcrum of wings 164. The upward force is primarily resisted by the limb bolt and rocker which are anchored to the riser and thus prevent movement of the limb pocket piece. Because of the gap between the limb bolt and the limb ends, forces transmitted through the limbs are in turn transmitted through the limb covers and the body portion to the limb bolt. In effect, compared to arrangements where the limbs extend the full depth of the limb pocket, a shorter length of each limb is captured within each limb pocket assembly 50. Instead, the limb pocket piece 150 becomes part of the lever arm. The shorter captured limb length functions as a shorter effective lever arm within the limb. This allows the limbs to bend more and also allows for smaller loads to be translated to the riser.

In a separate aspect, the structure at each end of the riser 20 supports the limb pocket in a “tripod” stance having a single forward connection portion and two spaced apart rearward support points. In more detail, as illustrated in FIG. 9 and other figures, upper riser end 22 includes a pair of vertical forward strut portions 123. Strut portions 123 are angled to converge to form a central forward connection point 124 on end 22. A pair of rearward strut portions 125 are substantially vertical and primarily parallel. The axes of rearward strut portions 125 do not intersect within the height of riser 20. Rearward strut portions 125 respectively terminate in a pair of spaced apart rearward support points 126 on riser end 22. An open gap is defined between rearward support points 126 and separates them. This provides a tripod defined by a central forward support point and a pair of spaced apart rearward support points for limb pocket assembly 50. For each limb pocket, forward end 154 is secured to the forward connection portion, and the rearward end 162 of the limb pocket is secured to the riser at the pair of rearward support points 126. A pair of fasteners may be used to secure two portions of rearward end 162 to rearward support points 126. In certain embodiments, limb pocket rearward end 162 defines a pair of downward extending tabs which are arranged between rearward support points 126. Fastener passages in the downward extending tabs are aligned with fastener passages in rearward support points 126. The fastener passages may also be aligned with fastener passages defined in sideplates 58. The tripod stance helps create a stable platform that resists riser flex during use.

Still further, riser 20 is formed with a substantially open framework with a series of openings and front-to-rear passages defined through riser 20 both above and below sight window 26. As illustrated, upper end 22 and lower end 24 are each formed by an open framework of struts forming spaced apart sidewalls, for example with one sidewall formed by a forward strut portion 123 and a corresponding rearward strut portion 125, and an opposing sidewall formed by the other forward strut portion 123 and the other rearward strut portion 125. A pattern with a framework of struts defining open sidewalls and a series of open front-to-rear passages is continued along the majority of the height of riser 20, with the exception of handle portion 28. The sidewalls are connected at selected heights by the riser ends, the handle and/or cross-struts. The framework also defines a series of side-to-side openings and passages.

Traditional riser assemblies do not have a framework of spaced apart sidewalls with open front-to-rear passages extending the height of the riser and/or above or below the sight window. At most, a shoot-through bow arrangement may have spaced apart sidewalls within a sight window portion. In contrast to traditional risers, advantages of riser 20 include spacing the bracing structure more widely, providing better stability and reducing potential torque or twisting of the riser. Other advantages include reduced mass and providing greater visibility, especially through the riser in portions aligned with the sight window while maintaining sufficient strength and stability within the framework.

While the disclosure has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.

Claims

1. An archery bow, comprising: a. an archery bow riser with opposing ends;b. a pair of bow limbs extending from the opposing ends of the riser, each limb having a butt end;c. a limb pocket arranged at each opposing end of the riser;d. a limb bolt anchoring each limb pocket to the riser; and,e. wherein the butt ends of the limbs are engaged within the limb pockets and wherein the butt ends are offset rearward of the limb bolts.

2. The archery bow of claim 1, wherein the limb pockets each include a portion extending from the limb bolt to over a respective limb butt end and bridging the distance that the limb butt end is offset rearward of the respective limb bolt.

3. The archery bow of claim 2, wherein each limb pocket defines a cavity to receive a limb butt end and defines a stopwall abutting a forward face of the limb butt end, wherein the stopwall is spaced rearward of the respective limb bolt.

4. The archery bow of claim 1, comprising a pair of bow limbs attached to and extending from each opposing end of the riser; each limb having a butt end, a tip end and a hinge section and wherein the butt ends of a pair of limbs are engaged within each limb pocket; and wherein the butt ends of the pairs of limbs are spaced rearward of the respective limb bolts.

5. The archery bow of claim 4, wherein each limb bolt defines an axis, wherein forward faces of each pair of limbs define a plane and wherein the limb bolt axis is substantially parallel to and spaced forward from the plane defined by the forward faces.

6. The archery bow of claim 1, wherein each limb pocket defines at least one cavity with an inner sidewall, a top wall portion and an outer side wall which abut and engage a respective limb butt end and wherein each limb pocket defines a wing spaced rearward of the at least one cavity, wherein the wing abuts a lower surface of the limb and defines a fulcrum point for the limb.

7. The archery bow of claim 6, wherein the at least one cavity defines a stopwall abutting a forward face of a respective limb butt end, wherein the stopwall is spaced rearward of the respective limb bolt.

8. The archery bow of claim 6, wherein the at least one cavity has an open lower side which does not engage a limb butt end.

9. The archery bow of claim 6, comprising a pair of sideplates including a downward extending sidewall portion which is arranged adjacent an outer sidewall of a limb butt end and an upper lateral portion extending from the sideplate over a limb; and wherein each sideplate is secured to a rearward end of a limb pocket.

10. An archery bow, comprising: a. an archery bow riser with opposing ends;b. a limb pocket arranged at each end of the riser;c. two pairs of bow limbs, with one pair of bow limbs extending from each end of the riser, each limb having a butt end, a hinge section and a tip end;d. a rotational member mounted between the tip ends of each pair of bow limbs;e. wherein the butt ends of each pair of limbs are engaged within a cavity defined by a limb pocket wherein the cavity includes a top wall portion abutting an upper facing surface of the limb butt end;f. wherein the hinge section of each limb is engaged by a wing of the limb pocket wherein the wing is spaced rearwardly of the cavity;g. a limb bolt anchoring each limb pocket to the riser; and,h. each limb has a forward face spaced rearward of the respective limb bolt.

11. The archery bow of claim 10, wherein the limb pockets extend from a forward end engaged by a limb bolt to the top wall portion with the limb pocket bridging the distance that the limb butt end is offset rearward of the respective limb bolt.

12. The archery bow of claim 10, wherein each riser end defines a forward connection portion and a pair of spaced apart rearward support points with an open gap defined between the pair of rearward support points, and wherein a forward end of one of the limb pockets is secured to the forward connection portion and a rearward end of the limb pocket is secured to the riser at the pair of rearward support points.

13. The archery bow of claim 12, comprising a pair of fasteners securing the rearward end of the limb pocket to the pair of spaced apart rearward support points.

14. The archery bow of claim 12, comprising a pair of sideplates including a downward extending sidewall portion which is arranged adjacent an outer sidewall of a limb end and an upper lateral portion abutting an upper limb face and extending from the sideplate to an anchor position between the limbs; wherein each sideplate is secured to a rearward side portion of the limb pocket; and wherein each sideplate is secured to an anchor position of the limb pocket between a pair of limbs.

15. An archery bow, comprising: a. an archery bow riser with opposing ends;b. a bow limb attached to and extending from an end of the riser;c. a limb pocket arranged at an end of the riser and securing the bow limb to the end of the riser;d. wherein a forward end of the limb pocket end is secured to the riser end at a single forward connection portion; and,e. wherein a rearward end of the limb pocket is secured to the riser end at a pair of spaced apart rearward support points with an open gap defined between the pair of rearward support points.

16. The archery bow of claim 15, wherein the riser comprises a pair of spaced apart forward strut portions angled to converge to form the single forward connection point; and, a pair of spaced apart rearward strut portions terminating in the pair of spaced apart rearward support points, wherein a front-to-rear passage through the riser is defined on an axis extending between the forward strut portions and between the rearward strut portions.

17. The archery bow of claim 15, wherein the riser defines a sight window formed as a front-to-rear passage between a pair of spaced apart sidewall portions, the riser further defining first and second front-to-rear passages above and below the sight window, each passage defined between a pair of spaced apart sidewall portions.

18. The archery bow of claim 17, wherein the first and second front-to-rear passages are adjacent the riser ends.

19. The archery bow of claim 16, wherein the riser is defined by an open framework of struts forming a series of front-to-rear passages between the spaced apart sidewalls, with the spaced apart sidewalls comprising the majority of the height of the riser excluding a handle portion.

20. The archery bow of claim 16, wherein the riser is defined by an open framework of struts forming a spaced apart pair of sidewalls excluding a handle portion, wherein the spaced apart sidewalls are connected at selected heights by the riser ends, handle and cross-struts to define a series of front-to-rear passages along the riser height.