US3196860A

US3196860A - Archery bow

Info

Publication number: US3196860A
Application number: US121709A
Authority: US
Inventors: Jr Earl H Hoyt
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-07-03
Filing date: 1961-07-03
Publication date: 1965-07-27
Anticipated expiration: 1982-07-27

Description

United States Patent greases ARCHERY 30W Ear-i H. Hayt, in, 11510 Natural Bridge Road, Bridgeton, Mo. Filed July 3, 1961, Ser. No. 121,709 Ciaims. (Ci. 124-44) This invention relates to archery bows and particularly to means in a bow for effectively damping out translatlonal and rotational movements which archers frequently and inadvertently impart to a bow at the instant of release of an arrow.

While merely increasing the weight of a bow handle portion tends to reduce translational movements, such mere weight increase as would be required to appreciably reduce rotational movements occurring under shooting conditions would render the bow objectionably heavy.

The primary object of the invention is to achieve a substantial increase in the mass moments of inertia about longitudinal and transverse axes through the center of gravity of a bow without objectionably increasing the total bow weight.

A further object is to provide an archery bow having a bow handle section including one or more integrally formed or rigidly attached weighting elements which are spaced perpendicularly a sufiicient distance from a longitudinal or transverse axis through the center of gravity of a bow, or arranged so as to be spaced perpendicularly from both axes a sufiicient amount to effect an increase in the mass moment of inertia about one or both of these axes which will appreciably reduce any angular movements of the bow about one or both of these axes as well as any translational movements which occur under shooting conditions at the instant of arrow release due to flinching, or to misalignment of the pushing and pulling forces being applied to the bow by the archer when at full draw.

A further object is to provide one or more weighting elements adapted for use on an archery bow and to provide means on a non-flexing portion of a bow spaced perpendicularly from a transverse axis through the center of gravity of the bow for the convenient detachable mounting of said element or elements rigidly thereon.

A further object is to provide an archery bow having one or more weighting elements extending perpendicularly from a longitudinal axis through the center of gravity of the bow, which element or elements are mounted on a non-flexing portion of the bow handle section for convenient adjustable positioning along the longitudinal bow axis.

A further object is to provide an archery bow having one or more weighting elements extending perpendicularly from a longitudinal axis through the center of gravity of the bow, which element or elements are mounted on a non-flexing portion of the bow handle section for convenient adjustable positioning along a line perpendicular to the longitudinal bow axis.

Further objects and advantages will appear from the following description when read in connection with the accompanying drawing.

In the drawing:

FIG. 1 is a side elevation of a bow constructed in accordance with a first form of the invention. In this form of the invention weighting elements are spaced perpendicularly from X and Y axes through the center of gravity of the bow and project from the back face of the bow;

FIG. 2 is a fragmentary side elevation of a bow constructed in accordance with a second form of the invention. In this modification weighting elements are spaced perpendicularly from X and Y axes through the cenassassin Patented July 2'57, 1965 ter of gravity of the bow and project perpendicularly from both sides of the bow;

FIG. 3 is a fragmentary side elevation of a bow constructed in accordance with a third form of the invention showing means for projecting the weighting element outwardly from the transverse axis XX beyond the nontlexing portion of the handle section;

FIG. 3a is a fragmentary side elevation of a bow constructed in accordance with a fourth form of the invention in which the weighting element is formed as a rigid part of the handle section;

FIG. 4 is a partial side elevation of a bow constructed in accordance with a fifth form of the invention in which weighting elements projecting from the rear face of the how are arranged for adjustable positioning along the longitudinal Y--Y axis of the bow;

FIG. 5 is a back face view of the bow shown in FIG. 2 and is taken on line 55 of FIG. 2;

FIG. 6 is a detail view of a method of detachably mounting the weighting elements on the bow shown in FIG. 1;

FIG. 7 is a cross-sectional view taken on line 77 of FIG. 4; and

FIG. 8 is a detail view showing a method of adjustably positioning weighting elements, as shown in FIGS. 1, 2, and 4, along a line perpendicular to the longitudinal YY axis of the bow.

Referring to the drawing, the bows shown in FIGS. 1 to 4 comprise a handle section generally indicated at 10 and upper and

lower bow limbs

12 and 14, respectively. The handle section 10 has a front face facing the bow string and an opposite back face and is formed with a hand-gripping portion 16, an arrow seat 18, and a cutout portion or sight window 20. The handle section 10, between points A and B at least, is inflexible in the sense that under normal shooting conditions the effect of any flexing of this portion of the handle section upon the operation of the bow is negligible. While not essential to achieving advantages of the present invention, the design of the bow is preferably such that its center of gravity lies close to the center of reaction pressure applied by the archers bow-gripping hand when drawing the bow.

On the back face of the bow shown in FIG. 1 are a pair of pads or bosses 22 spaced above and below a horizontal dot-dash line XX through the center of gravity of the bow, which line will hereinafter be referred to as the transverse axis. The pads 22 are located on inflexible portions of the bow handle section within the limits of points A and B and may be formed as an integral part of a solid, one-piece, bow handle section or they may be permanently attached thereto by gluing or some other suitable means. The handle sections of most modern bows are for reasons of strength and ornamenta-. tion laminated, the laminations being constructed of various hardwoods and being bonded by an extremely strong, epoxy resin glue so that any pads such as 22 which are glued to such laminated handle sections in the same manner in which the laminations are bonded may logically be regarded as integral parts of such handle sections.

Attached at their bases to pads 22 and extending perpendicularly from the back face of the how are posts 24 which carry spherical weighting elements 26 at their outer ends. The posts 24 also project perpendicularly from a dot-dash line Y--Y through the center of gravity of the bow, which line will be referred to hereinafter as the longitudinal axis of the bow.

FIG. 6 of the d-rawingshows means for the convenient detachable connection of the posts 24 to the bow handle section 10. The means comprises an externally and internally threaded bushing'ZS which is threadedly engaged in a tapped hole in the bow handle section and a threaded areaeeo stud portion 30 projecting axially from the base of post 24 which is received in threaded engagement in bushing 28. The fit of the external threads of bushing 28 in the tapped hole in the hardwood handle section may be made sufficiently tight so as to permit the post 24 to be unscrewed from a tightly screwed-in position in bushing 28 without rotating the .bushing in the wood handle section. It is to .be understood, however, that bushing 28 may be glued into the handle section, or secured by other means, so as to preclude the possibility of its being loosened in the process of installing or removing the posts 24 and that a suitable resilient washer may b included between the base of the post 24 and the end of bushing 28 to insure tight retention of the post.

The posts 24 and the spherical weighting elements 26 at the ends thereof may be formed integrally of brass or any suitable material having the desired weight, or the posts 24 may be made hollow or of wood or aluminum, and the spherical weighting elements of solid brass, steel, or other heavy material. By reducing the weight of posts 24 while still maintaining suflicient rigidity, the mass moment of inertia about the longitudinal axis YY is further increased for a given bow weight.

In the form of the invention shown in FIG. 2, four weighting elements are employed. In this arrangement the support posts of the weighting elements project from the sides of the bow; also, in this arrangement two of the elements are spaced oppositely with respect to the longitudinal bow axis YY on a line spaced upwardly from the transverse axis XX and the other two are spaced oppositely with respect to the longitudinal axis YY on a line spaced downwardly from the transverse axis XX. In this arrangement the weighting elements may, therefore, be balanced with respect to both XX and YY axes. ments from the side of the bow handle section, as shown in FIG. 2, instead of from the back face, as shown in FIG. 1, the illustrated arrangement in FIG. 2 has particular advantage in that it precludes any tendency of the weighting elements to twist the bow in the archers hand about the Y-Y axis when the bow is elevated or angled downward for uphill or downhill shooting, which may otherwise occur if weighting elements are projected from only one side of the bow. This tendency to twist the bow does not occur under bow inclinations for uphill or downhill shooting when the weighting elements are extended perpendicularly from the back face of the bow only, as in FIG. 1, or for that matter from the front face only. However, it may be desirable to extend the weighting elements perpendicularly from both front and rear bow faces in order to distribute the weight and avoid an objectionable unbalanced condition, particularly when heavy weighting elements are used. The use of an arrangement in which weighting elements project oppositely from front and rear faces of the bow is contemplated.

The posts 24, which carry the weighting elements 26 When it is preferred to project the weighting elein FIG. 2, are attached to the bow handle section by threaded engagement of their projecting stud portions 30 in the opposite ends of internally threaded sleeves 25, see FIG. 5. The sleeves 25 are press fitted in bores 27 extending transversely through the handle section from one side to the other.

In the form of the invention shown in FIG. 3, the weighting element 31 consists of a round bar of any diameter, length, and material required to attain the desired weight, and it is carried rigidly fixed to the outer end of a curved arm 32, the inner end of which is rigidly attached to a pad 34 formed on the back face of the bow handle section. In this arrangement the moment of inertia of the weighting element 31 with respect to transverse axis XX is considerably increased by the extension thereof beyond the end of the inflexible portion of the handle section. It will be understood that attachment of the weighting elements to any portion of the bow handle section or to an adjacent connected inner end of a bow limb which flexes appreciably when shooting would be highly undesirable, primarily because any attaching means at such point on the bow requiring partial or complete perforation would weaken the bow at that point and the attachment of any rigid element at that point by other means, such as gluing, would change the flexing curve of the bow. A further objection is that any weight attached to the flexing portion of the bow limb even though the flexing of that porion is relatively slight, tends to increase recoil and slow down the bow limb.

In the form of the invention shown in FIG. 3a, the mass moment of inertia with respect to both transverse and longitudinal bow axes is increased by a portion 35 of the bow handle section which projects outwardly from the back face of the bow. The portion 35 preferably consists of hardwood which is bonded to the adjacent lamination of a laminated wood, bow handle section 10 with the same bonding agent used to bond the laminations of the handle section. The portion 35 may include an element 37 which may be a ball or rod of heavier material, such as brass, which may be pressed into a bore in the outer end thereof.

In the form of the invention shown in FIG. 4, weighting elements and support posts of the type employed in the form of the invention shown in FIG. 1 are used and are mounted in channel members 36 for adjustable positioning along a line substantially parallel with the longitudinal bow axis. The channel members 36 are attached to flat pads 38 on the back face of the bow handle section by screws 40. The channel members 3d are provided with short inwardly extending flanges 42 at their open sides, see FIG. 7. A block 44 slidable in channel 36 has a threaded perforation therethrough which receives in threaded engagement the threaded stud 30 projecting from the end of post 24. When post 24 is turned to a tightened position, the short flanges 42 of the channel are clamped between the end of post 24 and the block 44, and when post 24 is turned to an unclamped position, it may be moved along the channel 36 with block 44 to any desired position. The channels 36 extend somewhat beyond the non-flexing limits A and B, as indicated, to permit greater spacing of the weighting elements from the transverse XX axis.

PEG. 8 shows means whereby the weighting element 48 of FIGS. 1, 2, and 4 may be adjusted so as to vary their perpendicular spacing with respect to the longitudinal YY axis of the bow. The means comprises a support post base 46, a threaded attaching stud 48 projecting from one end of the base, and an elongated threaded post 5i) projecting from the other end of the base. A weighting element 52 of any suit-able material such as a solid brass sphere, having a threaded perforation therein to threadedly receive post 50 is mounted on post 50 and locked in any threadedly adjustable position along the post by a lock nut 54.

In shooting a bow, any translational or angular movement of the bow about its transverse or longitudinal axis which occurs in the interval between the instant of release of the arrow and the instant it leaves the bow obviously diverts the point of impact of the arrow from the point at which it is being aimed at the instant of release. Most frequently the more pronounced movements of the bow Initiated at the instant of arrow release are caused by flmching or by a misalignment of the pushing and pulling forces being exerted by the archer when holding the bow at full draw. In flinching an archer may apply a twisting or hnear force to the bow in any direction or a combinatlon of both. In the absence of flinching, misalignment of the pulling force with the pushing force when the bow is at full draw effects the application of linear and-torsional forces to the bow or a twisting force applied to the bow handle applies a torsional force, which forces act when the bow string is released to impart translational and angular movements to the bow. Other slight translational and angular movements are imparted to the bow by the inherent shifting of the center of gravity of the bow and arrow, by the lateral thrust of the arrow as it is being accelerated, and as the bow is changing shape from full draw to braced position.

Recent extensive comparative tests conducted by several expert archers using bows constructed in accordance with the present invention and conventional bows of similar design and quality indicate that the shift of the point of impact from the point of air is frequently caused by angular movements of the bow, either about its transverse axis, its longitudinal axis, or both, which result from torsional forces being applied to the bow at the instant of release. The importance of reducing these angular movements of the bow and the effectiveness of applicants invention in accomplishing this was further clearly indicated in a number of comparative tests conducted with two bows of identical design, the first of the two bows including weighting elements positioned in the manner taught in applicants invention so as to considerably increase the mass moments of inertia about the transverse and longitudinal axes of the bow and the second of the two bows being of similar weight but having the added weight distributed in the handle section. The considerably smaller average diameter groups of successive arrows shot from the first bow over those groups shot from the second bow by the same archers forms the basis for applicants statements.

When considering the fact that the increase in the mass moment of inertia about either the transverse axis or longitudinal axis of the bow, due to the addition of weight, varies as the square of the distance between either of these axes and the center of gravity of the added weight, the considerable stabilizing effect achieved by the provision and arrangement of applicants weighting elements will be appreciated.

While the spacing of weighting elements perpendicularly from the longitudinal axis of the bow at any angular position about this axis appreciably increases the mass moment of inertia to resist twisting forces about this axis, the extension of weighting elements from the back face of the bow, as shown in FIG. 1, also appreciably increases the mass moment of inertia about the archers wrist joint and about the ball and socket joint at the shoulder blade and humerus of the archers bow arm to resist oscillation of the entire bow as well as rotation about its longitudinal axis. When the ulna and radius bones of the forearm are locked in alignment with the humerus of the upper arm at full draw, translational movements of the bow which occur are in fact frequently angular movements about the wrist joint or the shoulder joint. For this reason the spacing of weighting elements from the rear face of the bow has an additional advantage.

Other arrangements which employ the formation on or the attachment of weighting masses to the rigid, nonfiexing portion of a bow handle section in spaced relationship to transverse and longitudinal axes passing through the center of gravity of a bow will occur to those skilled in the art, and the exclusive use of all such arrangements which fall within the scope of the appended claims is contemplated.

The foregoing description and the drawing are intended to be illustrative, not limiting, the scope of the invention being set forth in the appended claims.

I claim:

1. In an archery bow having upper and lower flexible limbs and an elongated non-flexing handle section therebetween on which an intermediately positioned handgripping portion is formed; the improvemnt which comprises at least one integrally formed weighting portion projecting laterally from said handle section, said projecting weighting portion being disposed so as to be entirely free of contact with any part of an archers body and in a position removed from the path of movement of the bow string under shooting conditions, and said projecting weighting portion having sufficient lateral projection from said handle section to substantially increase the mass moment of inertia resisting rotation of the bow about a longitudinal axis through said handle section over a bow of similar design and similar total weight without such laterally projecting portion thereof.

2. An archery bow as set forth in claim 1 in which said integrally formed laterally projecting weighting portion is also spaced longitudinally along said handle section from said intermediately positioned hand-gripping portion sufiiciently to substantially increase the mass moment of inertia resisting rotation of the bow about a transverse axis passing through said hand-gripping portion of said handle section.

3. In an archery bow having upper and lower flexible limbs and an elongated non-flexing handle section therebetween on which an intermediately positioned handgripping portion is formed; the improvement which consists in the provision of at least one weighting element attached to said non-flexing handle section and projecting laterally therefrom, said weighting element being disposed so as to be entirely free of contact with any part of an archers body and in a position removed from the path of movement of the bow string under shooting conditions, and said weighting element having its center of gravity suiiiciently spaced laterally from said elongated handle section to substantially increase the mass moment of inertia resisting rotation of the how about a longitudinal axis through said handle section.

4. An archery bow as set forth in claim 3 in which the center of gravity of said weighting element is also spaced longitudinally along said handle section from said hand-gripping portion sufiiciently to also achieve a substantial increase in the mass moment of inertia resisting rotation of the bow about a transverse axis through said hand-gripping portion of said handle section.

5. An archery bow as set forth in claim 3 in which the center of gravity of said weighting element is spaced laterally from the back face of said handle section thereby to increase the mass moment of inertia about the joints of an archers bow arm under shooting conditions.

6. In an archery bow having upper and lower flexible bow limbs and a non-flexing handle section therebetween on which an intermediately positioned hand-gripping portion is formed, a support member having a portion thereof attached to said handle section and extending laterally therefrom, and a weighting element attached to said extending portion of said support member, said support member and said weighting element being disposed so as to be entirely free of contact with any part of an archers body and in a position removed from the path of movement of the bow string under shooting conditions, and said weighting element being of sufficient weight to substantially increase the mass moment of inertia about a longitudinal axis through said handle section.

7. An archery bow as set forth in claim 6 in which said support member also extends longitudinally outward from its point of attachment on said non-flexing handle section beyond one end of said non-flexing handle section, and in which said weighting element is attached to that portion of said support extending beyond the end of said non-flexing handle section thereby to also substantially increase the mass moment of inertia resisting rota tion about a transverse axis through said hand-gripping portion of said handle section.

8. An archery bow as set forth in claim 6 in which said weighting element is arranged for adjustable positioning along said extending portion of said support member.

9. An archery bow as set forth in claim 6 including cooperating means on said support member and on said handle section providing a readily detachable connection of said support member to said handle section.

tirely free of contact with any part of an archers body 10 or the string of the bow under shooting conditions and said weighting elements having their centers of gravity spaced sufiiciently laterally from said elongated handle section to substantially increase the mass moment of in- 8 ertia resting rotation about a longitudinal axis through said handle section.

References Cited by the Examiner UNITED STATES PATENTS 2,664,078 12/53 Irwin 124-24 2,816,537 12/57 Irwin 124-24 2,900,973 8/59 Diehr 12424 3,040,728 6/62 Niernan 12424 RICHARD C. PINKHAM, Primary Examiner.

JAMES W. LOVE, Examiner.

Claims

1. IN AN ARCHERY BOW HAVING UPPER AND LOWER FLEXIBLE LIMBS AND AN ELONGATED NON-FLEXING HANDLE SECTION THEREBETWEEN ON WHICH AN INTERMEDIATELY POSITIONED HANDGRIPPING PORTION IS FORMED; THE IMPROVEMENT WHICH COMPRISES AT LEAST ONE INTEGRALLY FORMED WEIGHTING PORTION PROJECTING LATERALLY FROM SAID HANDLE SECTION, SAID PROJECTING WEIGHTING PORTION BEING DISPOSED SO AS TO BE ENTIRELY FREE OF CONTACT WITH ANY PART OF AN ARCHER''S BODY AND IN A POSITION REMOVED FROM THE PATH OF MOVEMENT OF THE BOW STRING UNER SHOOTING CONDITIONS, AND SAID PROJECTING WEIGHTING PORTION HAVING SUFFICIENT LATERAL PROJECTION FROM SAID HANDLE SECTION TO SUBSTANTIALLY INCREASE THE MASS LONGITUDINAL AXIS THROUGH SAID HANDLE SECTION ABOUT A LONGITUDINAL AXIS THROUGH SAID HANDLE SECTION OVER A BOW OF SIMILAR DESIGN AND SIMILAR TOTAL WEIGHT WITHOUT SUCH LATERALLY PROJECTING PORTION THEREOF.