Elevation Adjustment Mechanism For Archery Bow Sights

Abstract

An arm, adapted for attachment to the side of an archery bow, supports an elongated base which mounts an elongated micrometer screw extending parallel to the plane of the bow. A sight-supporting block is mounted on the base for slidable movement parallel to the screw, and a latch is pivoted to the block for releasable engagement with the screw. When the latch is disengaged from the screw, the block may be moved manually along the base for coarse vertical adjustment of the sight, and when the latch is engaged with the screw, the latter may be rotated to effect precise vertical adjustment of the sight. The assembly is reversible for mounting on opposite sides of a bow, for use by right or left-hand archers.

Parent Case Text

This is a continuation of application Ser. No. 263,419 now abandoned, filed June 16, 1972.

Description

BACKGROUND OF THE INVENTION

This invention relates to archery bows, and more particularly to novel and versatile elevation adjustment mechanism which affords coarse and fine vertical adjustment of an archery bow sight.

Elevation adjustment mechanism for archery bow sights have been provided heretofore in a variety of structural configurations. However, they are all attended by certain limitations and disadvantages. Thus, some are incapable of precise adjustment. Others providing precise adjustment involve slow and combersome manual manipulation. Some are operable over a restricted range, so that the full range capabilities of the bow and archer are not obtainable. Still others are not adaptable for use by both right-hand and left-hand archers. Others are adaptable for mounting only on specific types of bows.

SUMMARY OF THE INVENTION

In its basic concept the elevation adjustment mechanism for archery bow sights of this invention utilizes a releasable latch on a sight-supporting block for releasable engagement with a micrometer screw, whereby to afford coarse and fine adjustment of the sight.

It is by virtue of the foregoing basic concept that the principal objective of this invention is achieved; namely, to overcome the aforementioned limitations and disadvantages of prior elevation adjustment mechanisms for archery bow sights.

Another important object of this invention is the provision of elevation adjustment mechanism of the class described in which the sight and mounting components are adjustable for precise alignment with a bow.

A further important object of this invention is the provision of elevation adjustment mechanism of the class described which is adjustable for either right or left-hand archers to extend the sight range substantially to the full limits of capability of the bow.

The foregoing and other objects and advantages of this invention will appear from the following detailed description, taken in connection with the accompanying drawing of a preferred embodiment.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a fragmentary view in side elevation of an archer in ready position for shooting an arrow from a bow equipped with elevation adjustment mechanism embodying the features of this invention.

FIG. 2 is a foreshortened view in side elevation of the elevation adjustment mechanism illustrated schematically in FIG. 1.

FIG. 3 is a front elevation as viewed from the right in FIG.

FIG. 4 is a fragmentary plan view as viewed from the top in FIG. 3.

FIG. 5 is a fragmentary sectional view taken on the line 5--5 in FIG. 3.

FIG. 6 is a fragmentary sectional view taken on the line 6--6 in FIG. 2.

FIG. 7 is a sectional view taken on the line 7--7 in FIG. 2.

FIG. 8 is a front elevation of the side and level component.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIG. 1 there is illustrated a conventional form of archery bow 10 provided with a hand grip 12, an arrow rest (not shown) above the hand grip, and a draw string 14 with knocking point (not shown) for receiving an arrow 16.

The elevation adjustment mechanism of this invention includes an elongated arm 20 adapted to be mounted on the side of an archery bow. For this purpose a mounting plate 22 is provided with a longitudinal dove-tail groove (FIG. 7) for slidably receiving the correspondingly shaped arm 20 slidably therethrough. A pair of spaced, countersunk openings 24 extend transversely through the plate for reception of screws by which the plate is secured to the side of a bow.

A pair of laterally spaced leaf springs 26 extend longitudinally across the base of the dove-tail groove, behind the arm, to provide a degree of resilient resistance to relative movement of the plate and arm, the opposite ends of the springs being bent back and seated in notches at the corresponding ends of the plate.

The arm is provided with a plurality of longitudinally spaced tapped openings 28 for the selective reception of an anchor screw 30. The outer end of the screw is knurled for convenient gripping between the fingers, and the inner end of the screw is tapered for reception in a correspondingly tapered socket in the base of the dove-tail groove in the plate. These corresponding tapers serve to center the screw as it is tightened, thereby positively securing the plate and arm together in the desired position of adjustment. The arm 20 thus is adjustable longitudinally of the plate 22, for adjusting the distance between a sight component and the eye of an archer, to accommodate various ranges of shooting.

The forward end of the arm is connected to a bracket 32 (FIG. 2) provided with the same dove-tail groove as the plate 22. A set screw 34 is threaded into a tapped opening in the arm for engagement with the bracket, to secure said parts together.

The bracket includes a pair of oppositely projecting ears each of which is provided with a longitudinal opening 36 for the reception of connecting screws 38. The openings register with tapped openings in the rear side of a vertically elongated base 40. These tapped openings preferably are located in the central area of the base and receive the screws 38 by which the bracket is secured detachably to the base.

It is desirable that the longitudinal axis of the base be oriented substantially parallel to the plane of the archery bow 10. Since the side of the bow to which the mounting block is secured may not be parallel to the plane of the bow, means is provided for adjusting the longitudinal axis of the base angularly relative to the bracket. Thus, one of the openings in the ears, herein designated opening 36', is elongated laterally to permit a limited degree of rotation of the base about the axis of the screw in the other opening.

The elongated base includes a correspondingly elongated guide 42 having a dove-tail shape in cross section. An elongated recess 44 is provided in the front surface of the guide for the removable mounting of a strip 46 (FIG. 4) of range marking paper, for the purpose explained more fully hereinafter.

The elongated guide slidably mounts a carriage 48 for a sight-supporting block 50. The carriage is provided with a dove-tail groove matching the shape of the dove-tail guide. A leaf spring 52 is interposed between the guide and groove, to provide a degree of resilient resistance to relative movement, the ends of the spring being bent back and seated in notches at the opposite ends of the carriage.

Means is provided for effecting coarse and fine adjustment of the sight-adjusting block along the base. To this end, a plate 54 is interposed between the carriage and block and secured by the mounting screws 56 which extend through registering openings in the block and plate and into registering tapped openings in the carriage. One of the openings 58 in the block is enlarged laterally to accommodate angular adjustment of the block relative to the carriage, for purposes described more fully hereinafter.

A lateral portion of the plate 54 is bent to U-shape to overlap one side of the carriage. The terminal portion of the bent section mounts a pivot pin 60 which, in turn, mounts a latch member 62 intermediate its ends.

One end of the latch member is bent inwardly to overlie the bent portion of the plate. It forms a finger button 64 by which to manipulate the latch member. The opposite end of the latch member is bent outwardly away from the carriage and is formed with an arcuate notch 66 arranged releasably to engage an elongated micrometer screw 68. A coil spring 70 encircles the pivot pin 60 and is engaged at one end with the underside of the finger button and at the opposite end with the U-shaped portion of the plate 54. The spring thus serves to urge the latch member resiliently toward engagement of the notch 66 with the micrometer screw.

The screw 68 is mounted for axial rotation on the base by means of a pair of spaced bearing members 72 secured to the base by means of screws 74. One end of the screw is provided with a knurled knob 76 to facilitate rotation of the screw. The rotational axis of the screw is disposed parallel to the line of movement of the carriage and sight-supporting block on the guide.

Thus, when the finger button is depressed the latch member is pivoted about the pin 60 to retract the arcuate notch from the screw. The carriage and attached sight-supporting block thus are freed to be moved manually along the guide, to achieve a coarse adjustment of elevation of a sight.

On the other hand, when the finger button is released, the spring 70 urges the latch member pivotally about its pivot pin in the direction to engage the notch 66 with the micrometer screw. Thus, upon rotation of the knurled knob 76 and the attached micrometer screw, the carriage and sight-supporting block are moved precisely along the guide to achieve a fine micrometer adjustment of elevation of the sight.

In the use of the elevation adjustment mechanism described hereinbefore, it is necessary that it be calibrated for the bow on which it is mounted. Thus, the strip 46 of paper is glued to the recess 44 in the guide and various test shootings are made at various ranges. The desired elevation adjustments for the various ranges then are marked on the paper in registry with the index marker 80. This marker comprises an offset portion of a rod 82 (FIG. 5) which is mounted adjustably in an opening in the carriage 48 and secured in desired position of adjustment by a set screw 84.

In the embodiment illustrated, the sight-supporting block 50 is provided with a transverse bore 90 (FIG. 5) which slidably receives a collar 92 for longitudinal movement therein. A locking screw 94 is threaded into a radial, tapped opening in the collar. The outer end of the screw is retained slidably in a longitudinal slot 96 in the block and thus serves to prevent rotation of the collar within the bore. The inner end of the screw bears frictionally against an elongated, threaded, sight-supporting rod 98 which extends through a tapped central bore in the collar. The inner end of the locking screw preferably is formed of nylon or other suitably soft synthetic resin or metal in order to prevent damage to the threads of the rod.

The threaded rod extends through the block, and one projecting end thereof mounts an adjusting knob 100 provided with an internally tapped bore. The inner end of the knob is reduced in diameter to provide a guide shoulder 102 which is freely received in a reduced diameter portion 90' of the bore. Interposed between the rear surface of the knob and the adjacent surface of the block is a resilient O-ring 104 which serves as a cushion between the parts and also to provide a degree of friction therebetween to resist rotation of the knob.

A coil spring 106 is contained within the bore of the block, surrounding the threaded rod. It bears at one end against the end wall of the block and at its opposite end against the collar. A projecting hub 108 of reduced diameter on the collar serves to center the spring.

The spring thus functions to urge the collar, and hence the threaded rod and mounted adjusting knob, resiliently toward the right in FIG. 5. The limit of such movement is adjustable by the knob, and is limited by abutment of the resilient O-ring against the confronting surface of the block.

The oppositely projecting end of the threaded rod 98 mounts an archery bow sight 110. In the embodiment illustrated, the sight is integrated with a bubble level 112 contained in a cylindrical housing 114 secured to and projecting from the rod 98. The sight per se is formed of a length of resilient metal bent to circular shape and confined releasably within a cylindrical shell 116 secured to the cylindrical housing of a bubble level. One terminal end of the resilient metal sight is bent inwardly to the axial center of the shell, and provided with a tiny ball tip, as illustrated.

The structural arrangement of the sight-supporting block assembly accommodates lateral adjustment of the sight relative to the block, by appropriate rotation of the adjusting knob 100. During such rotation of the knob, the threaded rod is restrained against rotation by frictional engagement of the inner end of the locking screw 94. Thus, the vertical position of the sight remains unchanged while it is adjusted laterally. This lateral adjustment is a windage compensation adjustment, as will be understood.

On the other hand, when the entire elevation adjustment mechanism is reversed on the archery bow, as explained more fully hereinafter, it is necessary that the sight be rotated 180.degree.. This is accomplished merely by grasping the sight shell and bubble housing between the fingers and rotating them, together with the threaded rod, through 180.degree.. During this rotation the adjusting knob 100 is restrained against rotation by virtue of the friction provided by the O-ring 104.

The adjusting knob may be provided with numerical quadrant indicia about its circumference to assist an archer in reestablishing predetermined positions of lateral adjustment of the sight, as established by previous trial and error tests.

The arrangement of components illustrated in the drawing is for a right-handed archer. Thus, the arm 20 is mounted by the plate 22 on the right-hand side of the bow (FIG. 1) and the sight 110 extends laterally to the left. If the elevation adjustment mechanism is to be mounted on a bow for use by left-handed archers, the arm mounting plate 22 is secured to the left side of the bow and the sight 110 is arranged to extend laterally to the right, as viewed by the archer.

If it is desired to extend the range of sighting, the arm is removed from the plate, by loosening the anchor screw 30, and the assembly rotated 180.degree. to place the sight closer to the archer. This reversal of the arm also must be accompanied by rotation of the sight 180.degree., as will be understood. Also, if it is desired that the micrometer screw knob 76 be located at the upper end of the assembly, the micrometer screw may be reversed on the base by disconnecting the screws 74 mounting the bearing members 72 on the base, and reversing the micrometer screw and bearing assembly. These various adjustments are accommodated for the left-handed archer in the same manner as for a right-handed archer.

As previously mentioned, one of the openings 58 for one of the screws 56 mounting the sight-supporting block 50 on the carriage 48 is elongated laterally to accommodate angular adjustment of the block relative to the carriage. This allows precise leveling of the bubble level 112 when the bow is supported precisely in a vertical plane.

From the foregoing it will be appreciated that the present invention provides an elevation adjustment mechanism for archery bow sights which is extremely versatile in its ability and precise in its operation. The latch member 62 accommodates rapid coarse adjustment of elevation, by disengagement from the micrometer screw 68, and equally fast the highly precise fine adjustment of sight elevation by engagement of the latch member with the micrometer screw. The mechanism is adaptable for mounting on a wide variety of types of archery bows, to accommodate either right-handed or left-handed archers.

It will be apparent to those skilled in the art that various changes may be made in the size, shape, type, number and arrangement of parts described hereinbefore without departing from the spirit of this invention.

Claims

Having now described my invention and the manner in which it may be used, I claim:

1. Elevation adjustment mechanism for an archery bow, comprising:

a. an elongated base,

b. a sight support mounted on the outer surface of the base for movement longitudinally thereof and supporting a sight disposed laterally of the base,

c. an elongated micrometer screw mounted on the outer surface of the base and spaced from the sight support for rotation about an axis parallel to the line of movement of the sight support,

d. a latch member mounted on the sight support having a screw-engaging portion movable between an inoperative position disengaged from the screw for movement of the sight support freely along the base and an operative position engaging the screw for movement of the sight support along the base by rotation of the screw, and

e. base mounting means including

1. an elongated arm secured at one end substantially normal to the base intermediate the ends of the base and spaced from the sight support, latch member and screw for unobstructed movement of the latch member, rotation of the screw and movement of the sight support between the opposite ends of the base,

2. a mounting plate mounting the arm for longitudinal adjustment of the arm relative to the plate, and

3. means for attaching the mounting plate to an archery bow with the arm extending alongside the bow substantially parallel to the line of sighting of the bow, whereby longitudinal adjustment of the arm relative to the mounting plate effects adjustment of the distance between the sight and the eye of an archer, and with the longitudinal axis of the base disposed substantially parallel to the plane of the bow.

2. The elevation adjustment mechanism of claim 1 wherein the arm is reversible end for end relative to the mounting plate for positioning the base and sight selectively forward and rearward of the bow.

3. The elevation adjustment mechanism of claim 1 including a bracket secured to said one end of the arm, and adjustable pivot means securing the bracket to the base, spaced from said sight support, latch member and screw, for pivoting the base about an axis parallel to the longitudinal axis of the arm, for aligning the longitudinal axis of the base parallel to the plane of the bow.

4. The elevation adjustment mechanism of claim 1 wherein the sight support includes a carriage member mounting the latch member, a sight-supporting block mounted on the carriage member and supporting the sight and a bubble level, the level axis of which is disposed substantially normal to the longitudinal axis of the base, and adjustable pivot means interconnecting the carriage member and block for pivoting the block about an axis normal to the base, and to said level axis for leveling the bubble level when the plane of the bow is vertical.