US2967521A - Archery bow - Google Patents

Description

Jan. 10,

Filed Aug.

1961 PlKULA 2,967,521

ARCHERY BOW 15, 1956 2 Sheets-Sheet l v C .'/l4

INVENTOR. EM". PIKUL f/Mm vf (MA ATTORNEYS E. PlKULA ARCHERY BOW Jan. 10, 1961 Filed Aug. 15, 1956 2 Sheets-Sheet 2 FIG. 3

WW wwv ATTORNEYS United States Patent ARCHERY BOW Emil Pikula, 1994 Willey Ave., Cleveland, Ohio Filed Aug. 15, 1956, Ser. No. 604,240

1 Claim. (Cl. 12424) Th is invention relates to archery bows. The general objects of the invention are the provision of faster and more efficient bows, i.e., bows in which a greater perc'entage of the energy stored in the bow when drawn is imparted to the arrow than in bows heretofore known; the provision of bows that are smooth and pleasant to draw and to shoot; the provision of bows that are durable and of long life and the provision of bows that can be arrow is released, the arms of the bow are constructed as' lightly as possible to reduce the inertia of the arms and the arms are very highly stressed when the bow is drawn. Archers say that a bow is considered to be nine-tenths broken at full draw. It has been known that if bows could bemade shorter, their efficiency could be increased because of the reduced mass of the arms of the bow and because the shorter arms could be made of lesser crosssectional area and stillmaintain the same stiffness. However, heretofore it has not been possible to produce high quality, efiicientandfast short bows because of limiting dimensional factors.

One of these factors is theradius of curvature of the of the bow when it is drawn. If two bows are constructed to a conventional design, one having a length of five feet and the other a length of four and one-half feet,;and both bows are drawn to shoot arrows of the samel'eng-th, it is obvious that the radius of curvature of. the shorter bow at full draw will be less than the radius of curvature of the longer bow. The resulting sharper curve of the arms of the shorter how would stress the arms to a higher degree and reduce the durability of the short bow as compared to the long bow. Furthermore, if the two bows are of the same design, it will be evident that with the shorter bow, the fistmele (the distance between the bow string and the front of the handle when the bow is strung but not drawn) will be less with the shorter bow than with the longer bow. The fistmele must be a certain minimum, ordinarily about six inches or seven inches, in a good bow. Otherwise, the bow string will strike the archers wrist before the arrow is released, making it impossible to shoot the arrow accurately. This factor has also militated against the construction of short bows heretofore. The third important factor is the string angle; i.e., the angle between the two portions of the string that intersect at the arrow nock when the bow is fully drawn. Again it will be evident that with two bows that are designed alike, the string angle will be less with the shorter bow than with the 2,967,521 Pajtented Jan. 10, 1961 2 longer bow. The string angle in a high-grade how shouldnot be less than about 120. This factor has also impelled bow makers to construct long bows rather thanshort bows.

According to the present invention, bows can be made substantially shorter, for example, from six inches to one foot shorter, than conventional bows having the same pull. At the same time, the radius of curvature of the shorter bow need not be reduced as compared to the radius of curvature of the arms of the longer bow; the fistmele can be maintained as large as the fistmele of the longer bow, and the string angle can be maintained as large as the string angle of the longer bow. This is accomplished according to the present invention by providingthe bow with a handle that is offset away from the archer; or stated the other way, the arms of the bow are offset toward the archer from the handle. This offset makes possible the elimination of the difliculties that are} encountered when attempts are made to shorten bows of conventional design and makes possible the production of comparatively short bows having highly desirable char acteristics.

A bow made according to a preferred form of the invention is illustrated in the drawings wherein:

Figure 1 is a side elevation of a bow embodying the invention, the bow being made up or strung.

Figure 2 is a back elevation of the bow of Figure 1, and

Figure 3 is a side elevation of the bow of Figure 1 when it is drawn ready to shoot, Figure 3 showing in broken lines a comparison of the bow of the present invention with a conventional bow.

As shown particularly in Figures 1 and 2, a bow indi-' cated generally at 10 made according to the present invention embodies a handle or grip portion 11 which is grasped by the archer, relatively rigid central portions 12 and 13 on either side of the grip portion and merging into the grip portion, and flexible arms 14 and 15 which merge into the central portions 12 and 13. The bow string 16 extends between the ends of the arms as shown.

The bow is preferably of laminated construction; but inasmuch as laminated bows are well known in the art, it is not considered necessary to disclose the nature of the laminations in detail in the present application. The central portions 12 and 13 and the grip or handle portion 11 are thicker than the arms, as shown, and are reinforced so that little, if any, bending of the bow takes place between the points marked a where the arms merge into the central portions. The upper central portion 12 is preferably cut away on both sides as indicated at 17 to reduce the width of this portion and thereby provide shelves or arrow rests 18 on either side of the central line of the bow so that the bow can be shot either right or left handed. The upper central portion 12 is given increased depth in a front-to-back direction in the cut away zone, as indicated at 20, in order to provide adequate strength and stiffness in this region. While this is a preferred form of the central section, other designs and constructions may be employed if desired.

In order to provide a bow that can be made compara tively short and yet at the same time maintain the required fistmele and string angle and avoid overstressing of the bow, the handle portion of the bow is offset away from the bow string as shown particularly in Figures 1 and 3. In a conventional bow, the front of the handle portion would be substantially in alignment with the arms of the bow where they join the central portions of the bow.

That is, the front of the handle portion of the bow would occupy approximately the position shown by the broken line b in Figure l. The amount that the handle is offset forwardly in applicants bow is indicated by dimension c in Figure 1; the ofiset provides a fistmele, indicated at d of the desired value without necessitating undue bending of the limbs of the bow when the bow is strung. As an approximate rule, it is possible to shorten each arm of the how about one'inch for each inch of forward ofiset of the handle while still maintaining the same fistmele and string angle as in a conventional bow. A handle that is offset a distance of about three inches makes it possible to construct a four and one-half foot bow having about the same fistmele, radius of curvature of the arms and string angle as a five foot bow of conventional construction.

A comparison of a four and one-half foot bow made according to the present invention and a five foot conventional bow is given in Figure 3, both bows being shown as fully drawn with an arrow of the same lengthin this instance, a 26-inch arrow. As indicated in the drawing, in which the conventional bow is shown in broken lines at 22, the string angle e is substantially identical for both bows and the. radius of curvature of the arms of both bows is approximately the same. As explained above, the offset handle also gives the same fistmele for the shorter bow as for the longer how. The shorter not only has the desired characteristics of the longer how but also has important advantages over the longer how. The shorter bow is lighter and easier to handle. Because the arms are shorter, they can be made narrower and thinner than the arms of the longer bow for the same pull, shorter arms being inherently stifier than longer arms. Thus, the bow is not only lighter because of its reduced length, but also lighter because of the reduced cross-section of the arms. The bow string is shorter and correspondingly lighter.

All of these factors produce a faster, more efficient bow. The shorter arms, being lighter in weight than the longer arms, have less inertia than the longer arms. The shorter bow string likewise has less inertia than the longer bow string. In a bow, much of the energy that is stored in the bow when it is drawn is utilized in accelerating the arms of the bow and the bow string. With bows of the present invention, the reduction in the mass of the arms of the bow and the bow string makes an important reduction in the amount of energy required to accelerate these components, with the result that the arms and the string move faster and more energy is available to accelerate the arrow. The reduced weight of the arms also improves the feel of the bow and its shooting qualities because the arms have less momentum to be dissipated after the arrow is released from the string. In bows with heavy arms there is a considerable shock each time the bow is shot, and this can be very tiring to the archer. The reduction in the length, width and thickness of the arms and the reduction in the length of the bow string also reduce the windage of these components and again leave more energy to be transmitted to the arrow. The result is that a four and one-half foot bow made according to the present invention and having the same pull as a five foot bow constructed of the same materials and made to the best conventional design will impart to the same arrow an initial velocity about 15 percent greater than the five foot bow; or if desired, a shorter bow can be constructed with about 15 percent less pull than a conventional, longer bow and yet give an arrow of the same weight and length an initial velocity the same as the longer bow.

Those skilled in the art will appreciate that various changes and modifications may be made in thepreferred form of the invention disclosed herein without departing from the spirit and scope of the invention. The essential characteristics of the invention are set forth in the appended claim.

I claim: An archery bow having a bow string and comprising a single conventional hand grip. handle portion, two relatively rigid central portions on either side of and merging into said handle portion, and two flexible arm portions on either side of and merging into said central portions, substantially parallel to said handle portion, said arm portions being rearwardly concave. when the how is braced, the space between said handle portion and said bow string being unobstructed; said handle portion being. offset from said central portions in a direction away from said how string, the lengths of said arms and the length of said bow string being such that the string angle of said how and the radius of curvature of the arms of said how when fully drawn with an arrow of a given length are at least equal to the string angle and the radius of curvature of the arms of a bow of substantially greater overall length and not having a handle ofiset away from its bow string when fully drawn with an arrow of the same length; the fistmele of said bow being at least equal to the fistmele of a bow having substantially longer arms of substantially the same curvature and angular relationship at their fixed ends and not having a handle ofi'set away from its bow string.

References Cited in the file of this patent UNITED STATES PATENTS 428,912 Holmes May 27, 1890 2,100,317 Hickman Nov. 30, 1937 2,423,765 Folberth et al. July 8, 1947 2,507,271 Ringel May 9, 1950 2,689,559 Meyer Sept. 21, 1954 2,900,973 Diehr Aug. 25, 1959 OTHER REFERENCES Archery: The Technical Side, printed in 1947, pages 152 and 175.

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