US3818888A

US3818888A - Bowstring release

Info

Publication number: US3818888A
Application number: US00392499A
Authority: US
Inventors: W Keeney; H Bolling
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-08-29
Filing date: 1973-08-29
Publication date: 1974-06-25
Anticipated expiration: 1991-06-25

Abstract

A bowstring release having a housing with a transverse-slot in its radial wall communicating with a longitudinal bore passing therethrough. The release has an axially movable plunger in the bore which has an ''''L'''' shaped slot forming a nib exposed at, and coacting with the transverse-slot to retain a bowstring passing therethrough. One end of the plunger protrudes from the housing bore as a trigger a spring opposes and a screw limits motion of the plunger. The radial wall has a flat portion that supports an arrow. The transverse-slot guides a bowstring on release of an arrow.

Description

United States Patent [191 Keeney et al.

[ 1 June 25, 1974 BOWSTRING RELEASE 1,150,038 7/1957 France 124/35 A Primary Examiner-Richard C. Pinkham Assistant ExaminerWilliam R. Browne Attorney, Agent, or Firm-John F. McClellan, Sr.

[57 1 ABSTRACT A bowstring release having a housing with a transverse-slot in its radial wall communicating with a longitudinal bore passing therethrough. The release has an axially movable plunger in the bore which has an L shaped slot forming a nib exposed at, and coacting with the transverse-slot to retain a bowstring passing therethrough. One end of the plunger protrudes from the housing bore as a trigger a spring opposes and a screw limits motion of the plunger, The radial wall has a flat portion that supports an arrow. The transverse-slot guides at bowstring on release of an arrow.

15 Claims, 12 Drawing Figures PATENTEB JUHZSIBM FlGb l BOWSTRING RELEASE This invention relates generally to projectile equip ment and specifically to archery bowstring releases.

Longbow archery is divided into three competitive classes, epitomized by the grip on the bowstring by which the bow is flexed and released, drawing the.

notched arrow rearward and projecting it.

In the Hunter Class the forefinger phalanx hooks around the bowstring above the arrow and the middle and third finger phalanxes hook around the bowstring below the arrow. In the Stringwalker Class, the forefinger, middle finger and third finger phalanxes hook around the bowstring below the arrow. In the Release Class a hand-manipulated mechanism of some type draws and releases the bowstring, only one moving part being allowed in releases in formal competition.

The Hunter Class may be said to represent the traditionalists, the Stringwalker Class the progressive traditionalists, who on the average shoot higher scores because of improved technique, and the Release Class the relative latecomers since the class is new, who on the average shoot still higher scores.

Striking characteristics of the Release Class are that the latecomers tend to become competitive with less experience than in the other classes, and that the consistency of results makes more feasible the use of sighting apparatus, still further improving accuracy.

Long known aides to drawing and loosing or releasing bowstrings include finger or thumb guards of various types and material including leather and bone. Some of these permit one digit to hook around another which draws the bowstring, loosing or releasing it by relaxation of the hooked digit.

Modern releases include the well-known loop and nail type, the rotating hook type, and the tab type. Illustrative U.S. Pats. include Nos. 3,604,407; 3,608,090; 3,656,467; 3,661,136. A plunger-released frictional arrow-gripper is illustrated in French Pat. No. 1,150,038.

Reproduceability of release has within the recent past in one jump advanced accuracy in archery beyond anything ever before possible. v I

Comparative newcomers now routinely score higher averages than the best conventional archers of fifteen or twenty years ago.

Learned treatises have been written on released arrow characteristics:

Arrows And Their Flight. An arrow is said to be properly matched to a bow, if when well loosed, it passes the bow smoothly, without impact against the arrow plate,.and takes off steadily on its flight. When thearrow is loosed, the lateral forces upon it cause it to bend, and to be set in oscillation about two nodal points, each approximately one-fifth to one-fourth the distance from the end of the shaft. The period of oscillation must be so related to the time of passage of the bow that the instantaneous displacement of the part of the shaft opposite the arrow plate is outward. When this condition obtains the arrow remains clear of the bow in passing, and flies precisely in the vertical plane defined by the line of aim. An arrow that is two stiff or too limber oscillates either two rapidly or too slowly for proper synchronization with its time of passage, which results in its impinging on the arrow plate somewhere along the shaft, with resultant deflection. Archery, Encyclopaedia Brittanica, 1966 Ed., page 296.

The above discussion continues with a description of means of testing the mass and stiffness or spine of arrows to determine to some degree which bows they will match and which not.

A principal object therefore of the present invention is to provide a bowstring release which at all times and with all equipment maximizes accuracy of arrow projection.

Another object is to provide a release as described which minimizes or eliminates bow-caused arrow oscillation.

Another object is to provide a. release as described which increases reproduceability of release under all conditions.

And another object is to provide a release as described which gives the user a clear sense of feel of, and sensitive control over, the relation of drawn bowstringto-release.

Still another object is to provide a release as described which gives the user a clear sense of feel of, and sensitive control over, the relation of arrow-to-release concurrently with but separate from the bowstring-torelease feel.

Yet another object is to provide a release which is sensitively adjustable to suit individual release-pressure needs, and for use with varying types and sizes of bow equipment.

A further object is to provide a release which induces the user to employ the strongest portions of his hand for drawing the bowstring and the less strong portions of his hand for trimming alignment and actuation of the release, and yet to aim and release with a relaxed hand.

Still a further object of the invention is to provide a releasewhich is instantly employable at any time.

Additional objects are to provide a release as described which is easy and natural to learn to use, which is adapted for both left-hand and right-hand use, which is simple, comfortable, safe, efficient, reliable, economical, and which is attractive in appearance.

In representative embodiment given for purposes of brief summary alone, the release includes an outer elongate member having an opening, an inner elongate v member having a nib coacting with a wall of the outer member opening aligned for bowstring retention and guidance, and a plunger-type mechanism for bowstring release from the nib.

Th above objects and advantages of the invention will become more readily apparent on examination of the following description, including the drawings, in which like reference numerals indicate like parts.

FIG. 1 is an isometric view of the release, with phantom lines representing details of the environment of use;

FIG. 2 is a side-elevation section adapted from 22, FIG. 1;

FIGS. 3, 4 and 5 are plan sections showing three positions of operation, adapted from 3-3, FIG. 1;

FIG. 6 is a plan diagram of the invention and a bowstring portion;

FIG. 7 is a side-elevation diagram of the invention and a bowstring portion;

FIG. 8 is a rear-elevation diagram of the invention and a bowstringportion;

FIG. 9 is a rear elevation;

FIG. 10 is a plan view;

FIG. 11 is a front elevation, and

FIG. 12 is an isometric exploded-assembly view.

FIG. 1 shows the release of this invention held in the hand H of an archer drawing a bowstring B engaged in transverse slot 12 of the release and engaging an arrow A nocked above the release, with the nocked end of the arrow resting on the release at a flat 14 .51 the release housing or body 16. The plane of the fiat is parallel with the arrow axis.

The release lies in a horizontal plane, transverse to the bow/bowstring plane, with the long axis 18 of the generally cylindrical, tubular housing or body of the release perpendicular to the bow. The housing is substantially as long as the nominal hand width of the human hand. The back of the archers hand faces upward, and his forefinger I, middle finger II and third finger III curve downward around the body of the release in the succession of

grooves

20, 22, 24 provided. The little finger IV of the archer fits in groove 26 across the end of the release and stabilizes and trims the position of the release. All grooves are proportioned to receive nominal-size human digits.

The archers thumb V is drawn to his chin C at the limit of draw in the usual manner, following which it depresses the end or trigger portion 28 of elongate plunger 30 which protrudes axially from the end of the release, opposite the end with the groove, for the loosing the bowstring and launching the arrow.

FIG. 2, a section adapted from 2-2, FIG. 1 shows the engagement of a bowstring B by nib portion 32 of circular-section plunger 30 within transverse slot 12 in the body 16 of the release 10, and the supportive relation of the body 16 to the rear end of an arrow A nocked on the bowstring B.

When nib 32 is axially translated on depression of plunger 30, the loosed bowstring casts the arrow. A preferred arrangement is shown in which the nocked end of the arrow rides against a side of the notch where it intersects flat 14, overlapping slightly at 34 in the view shown. This overlapping engagement which can be felt by the archer, who can center it by rotating the release 10 slightly, stabilizes the nocked end of the arrow along a straight edge at the instant of release. A nocking point N installed on the bowstring B just above the arrow helps position the arrow in the groove.

As will be seen, the release is preferably aymmetrical about the longitudinal centerplane through the nib, and

a second flat 14 when rotated to the top permits lefthanded use of the release in identical manner with the right-handed use described.

Preferably a relatively hard bowstring, such as the usual 12 strand Dacron is used, served as at S with Nylon" monofilament to co-act with most reproduceability with the structure of the release, both the capitalized names being Trademarks of the E. I. DuPont de Nemours Co.

FIGS. 3, 4 and'5 respectively show in plan-section the structure of the release 10 as it receives the bowstring B, as it retains the bowstring and as it releases the bowstring.

Plunger 30 is generally cylindrical and is constrained by the housing or body 16 to move axially within a sliding-fit cylindrical bore 38 of the housing or body under thumb-pressure of the user opposed by pressure of compression spring 40.

Length of stroke of the plunger is constant; screw 42, radially threaded through the wall of the body and bearing on the respective ends of axial slot 44 in theplunger, establishes the limits of travel of the plunger, and limits rotation of the plunger about the longitudinal axis.

Release pressure of the plunger is adjustably variable; plug screw 46 is axially threaded in the bore 38 of the body 16 preloads spring as required to suit individual circumstances. A keeper screw 48 radially threaded through the wall of the housing may be used to contact and lock the position of plug screw 46, if desired.

The combination of constant stroke and adjustable pressure permits the user to rely on the reproduceability of release while enjoying release pressure tailored to physical characteristics of the user.

The body 16 may be advantageously molded by polyurethane, and the plunger 30 may be formed of mild steel, preferably well polished.

Nib 32 is defined in the front periphery of plunger 30 by a generally L shaped slot 36 penetrating to the centerline of the plunger, parallel with the vertical center plane, leaving the nib as a cantilevered portion of the plunger periphery. The nib preferably is rounded, having approximately a half-thickness radius around the entire terminal portion in plan view, but, at the least around the inner face, leaving the remainder 50 of the inner face of the nib substantially parallel with the plunger. The plunger face 52 opposite the nib lies in a radial plane.

As indicated in FIG. 3, when fully open under plunger pressure against spring 40, the radial face 52 of slot 36 is substantially congruent with a face 54 of transverse slot 12 in the body. In plan view both slots extend past the centerline, preferably, and verticallythrough the respective pieces. Any portion of the nib still protruding into the housing slot at the FIG. 3 position should, as noted, present a rounded exterior, and the effective opening should be at least two bowstring diameters wide to facilitate introducing the bowstring.

As indicated in FIG. 4, when closed in the bowstringretaining position, the bowstring is freely retained in the depth behind the nib, and the plunger preferably closes only to the point at which the end of the flat inner face 50 of the nib 32, that is, the point at which the end-radius begins, just reaches the centerplane of the bowstring.

The periphery P of the bowstring on the opposite side of the nib rests against the flat guiding face 54 of transverse slot 12 in the body, on either side of the bore 38.

As indicated in FIG. 4, a very slight depression of the plunger 30 by the thumb of the user causes release of the bowstring. The bowstring stabilizes on first movement by wedging outward with peripheral portion P of the bowstring bearing against the radiused end of the nib 32 which it thrusts aside, and then continues outward, stabilizing against the radial or guiding face 54 of the transverse slot.

The initial edging action or release tends to prevent roll or twist of the bowstring about the axis of the bowstring, by equalizing friction on opposite sides of the circumference during the period of highest rubbing friction.

The usual lateral oscillation of the arrow caused by side motion of the bowstring on release is prevented by the guiding and by the crisp, friction equalizing release action, withthe result that vibrational energy-loss is conserved and the arrow flies dead-on in the vertical sighting plane.

Elimination of lateral oscillation makes the use of plastic vanes practical under conditions in which they could not before be used in place of feather fletching, resulting in higher velocities, lower trajectories, and less yaw in cross winds.

In addition, the broad area of manual grip combined with the precise release action substantially eliminates forward creep on release, assuring uniformity of distance in successive shots.

FIG. 6 indicates in isometric plan view diagram the relatively great lever arm L afforded the fourth or little 7 finger of the user in trimming rotation angle of the release 10 about a vertical axis at the bowstring B to square the guiding slot side 54 with the path of the bowstring. The drawing hand does not grip but is essentially relaxed since the first three fingers hook fully about the release and generally are called on to perform no other function than drawing.

The body end opposite the plunger end extends a distance from the plunger end nominally required to permit the human fourth finger to crook around the end,

fitting in the end concavity 26. By slight extension or retraction of the fourth finger the archer adjusts the angle in the horizontal plane until he feels the bowstring lie flat and secure against the guiding side 54 of the transverse slot.

The archer can also feel the arrow seat itself along the guiding edge 34 (FIG. 2) of the trough formed by guiding side of the slot where it intersects theflat 14 on the top of the release.

FIG. 7, a side elevation diagram of release 10 and bowstring B indicates that tension on the radially offset nib 32 corrects the angle of rotation about the long axis 18 of the release. Preferably a slight degree of rotational backlash is built into the release by making the axial or limit slot 44 (FIG. 3) about two thousandths wider than the diameter of screw 42, increasing sensitivity of feel. The user can assure himself that the flat l4 lies along the bottom of the arrow by slightly rotating the release about the long horizontal axis, as indicated.

FIG. 8, a rear-elevation diagram of release 10 and bowstring B indicates that the rotational angle of the release about an axis parallel with the arrow axis is also self-corrective, and is easily felt on rotating the hand as contact pressure between the bowstring and guide surface of the slot above and below the nib.

FIGS. 9, l and 11 indicate the essential symmetry of the release about the horizontal centerplane, the additional grips 20, 22', 24' 26 and the flat 14' on the opposite side making it equally useful for right-and lefthanders, and the unitary attractive appearance and damage resistant, easily-stored and quickly-deployable aspects of the invention.

FIG. 11 also shows a further preferred features of the nib 32, a symmetrical end-radius in the vertical plane, still further increasing the sensitivity and reproduceability of release by localizing the retention of the bowstring.

FIG. 12 illustrates the economy of construction and assembly of the release 10. The body 16, including the bore'38, transverse slot 12 and flats 14 can be molded, or machined, and the exterior can be further shaped to suit by the individual user, employing a file and sandpaper. The plunger 30 is simply fashioned by milling and polishing a length of steel rod to fashion and smooth the structures of the nib 32 and limit slot 44. The trigger end 28 is preferably made slightly convex for smoother engagement with the thumb.

The screws 42, 46 (and 48 if used) can be selftapping, or the screw holes 56, 58 and far end of the bore can be pre-threaded.

Different sizes of body or of nib 32 or of spring 40 can be substituted by unscrewing a single screw 42.

The transverse slot 12 in the body can be made as wide as desired since the bowstring tends to seat automatically against the guide face of the slot, facilitating capturing the bowstring quickly and surely under adverse conditions, as in hunting. Conversely, since the release conveniently hangs unsupported on the bowstring without fouling, hunters can keep hands warm in pockets until the instant of use without delay in stringing the release, or in further positioning it for drawing.

Obviously, many modifications and variations of the present invention are possible in light of the above teaching. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed and desired to be secured by United States Letters Patent is:

1. A manual bowstring-release for use in loosing arrows, comprising: an elongated housing a means mounted in the housing for manual reciprocation to releasably hold a bowstring, said means having a nib disposed longitudinally along one side of said means, said means having an opening defining the nib, the nib having an end spaced from a portion of the means by said opening for receiving a bowstring therebetween, the housing having a means positioned transversely to the opening for admitting a bowstring to be received by the nib, and said first mentioned means having a means free of the housing for receiving manual pressure to move the nib longitudinally so as to release a bowstring retained thereby.

2. A manual bowstring-release as recited in claim 1, means limiting the longitudinal movement of the nib with respect to the housing, the means in the housing having a wall longitudinally spaced from the end of the nib a distance providing for reception of said a bowstring therebetween at one said limit of movement of the first mentioned means and for retention of a bowstring by said wall and nib at another said limit of movement of the first mentioned means.

3. A manual bowstring-release as recited in claim 2, said wall being transverse to the length of the nib, thereby providing for stabilizing guidance of a bowstring by the wall on release of a bowstring.

4. A manual bowstring-release as recited in claim 3, the housing having'a longitudinal exterior surface perpendicular to and intersecting said wall, thereby adapting an edge of the wall at said intersection for guiding a portion of an arrow when loosed by said manual bowstring-release.

5. A manual bowstring-release as recited in claim 4,

' said longitudinal exterior surface being flat, and said 7. A manual bowstring-release as recited in claim 6, wherein said portion of the first mentioned means is free of the housing and protrudes from an end of the housing.

8. A manual bowstring-release as recited in claim 7, wherein a resilient member is provided within the bore of the tubular shape bearing on the first mentioned means thereby urging said protrusion of the first mentioned means portion from the housing, and wherein means is provided for adjusting the force with which the resilient member bears on the first mentioned means thereby adjusting pressure required for releasing a bowstring.

9. A manual bowstring-release as recited in claim 8, wherein the means for adjusting force of bearing of the resilient member comprises a screw, said screw being threaded in the bore of said tubular shaped housing.

10. A manual bowstring-release as recited in claim 9, wherein the resilient member comprises a compression spring and wherein the compression spring bears on an end of the first mentioned means.

11. A manual bowstring-release as recited in claim 2, wherein said opening defining the nib is L shaped, wherein the inner face of the nib is substantially parallel with the first mentioned means and hasan outward curved portion that extends around the end of the nib.

12. A manual bowstring-release as recited in claim 1, wherein said first mentioned means has a portion free of the housing which protrudes from a first end of the housing, and wherein the end of the housing opposite said first end has a groove there across nominally sized to receive a portion of a human digit.

13. A manual bowstring-release as recited in claim 12, wherein the housing is generally cylindrical and has a circumferential succession of digit grooves spaced therealong, and wherein said opening transverse to the nib lies between two of said digit grooves proximate said first end of the housing.

14. A manual bowstring-release as recited in claim 13, wherein the manual bowstring-release is substantially symmetrical about a longitudinal centerplane passing through said nib, thereby adapting said manual bowstring-release for both left hand and right hand use.

manual bowstring release.

Claims

4. A manual bowstring-release as recited in claim 3, the housing having a longitudinal exterior surface perpendicular to and intersecting said wall, thereby adapting an edge of the wall at said intersection for guiding a portion of an arrow when loosed by said manual bowstring-release.

5. A manual bowstring-release as recited in claim 4, said longitudinal exterior surface being flat, and said edge of the wall being straight.

6. A manual bowstring-release as recited in claim 3, the housing being tubular in shape, and the first mentioned means being disposed in the bore of said tubular shaped housing.

7. A manual bowstring-release as recited in claim 6, wherein said portion of the first mentioned means is free of the housing and protrudes from an end of the housing.

11. A manual bowstring-release as recited in claim 2, wherein said opening defining the nib is L shaped, wherein the inner face of the nib is substantially parallel with the first mentioned means and has an outward curved portion that extends around the end of the nib.

15. A manual bowstring-release as recited in claim 14, wherein said inner face of the nib extends substantially parallel with the first mentioned means a distance towards the end of the nib nominally sufficient to contact the centerplane of a bowstring retained in said manual bowstring release.