Pin Guard Bow Sight

This invention relates to an archer's multipurpose bow-sighting device that can be used as a cross-hair sight when used with conventional sight pins or as a bracketing sight, i.e. a pair of vertical members bracket the sight pin. It can also be adapted to provide a box sight, i.e. vertical bracket members and horizontal bracket members.

There are a multitude of sights available for archers' bows. The sight is typically mounted on a bracket which is fastened to the bow above the hand grip and arrow rest. It is typically used in conjunction with a peep sight accurately located on the bow draw string. Some of the types of sights include: a multi-pin sight having four or five pins, a multi-pin sight with a U-shaped pin guard protecting the pins, a multi-pin sight having a single vertical cross-hair, and various combinations of the above.

For instance, U.S. Pat. No. 4,136,462 discloses an adjustable cross-hair sight having the single vertical wire and a plurality of horizontal wires. The single vertical wire is mounted on a bracket that is adjustable horizontally thereby varying the distance between the vertical wire and the bow. This adjustment provides a sideways or windage adjustment and is accomplished by rotating a top and bottom bracket backing nut, a typical vertical cross-hair adjustment method. The problem with two adjusting nuts is that the bracket may become canted if the nuts are unevenly adjusted. The range adjustment is accomplished by moving the horizontal wires or pins up or down after loosening a set screw, a method common in the art.

It is the purpose of this invention to provide an easily adjustable pair of vertical cross-hairs that can be used to bracket the target, i.e. center the target between the vertical lines. A single knurled knob adjusts both hairs. It is also possible to "box" the target by attaching a pair of horizontal cross-hairs, retained between the pin guard and the bracket; and when used with the vertical cross-hairs, the target may be centered within the "box".

The invention incorporates a pair of flexible bands, such as rubber bands, attached between an upper and lower drive screw which in turn has an archer's bow pin guard inserted through the center of each screw. The U-shaped pin guard is mounted on a bracket that attaches to the bow above the hand grip and arrow rest. A pair of collets retain each screw on the upper and lower portions of the pin guard, allowing rotational motion of each screw about its longitudinal axis. The threaded ends of the upper and lower position of the pin guard are affixed to the bow bracket by conventional fastener consisting of knurled finger nuts, flat and lockwashers, hex nut, and square nuts matching the No. 8-32 thread of the threaded ends of the pin guard. Two flexible members or rubber bands are placed over the screw threads at an approximate 3/16" vertical distance from each other such that they are parallel to the vertical portion of the pin guard and also the bow. Rotation of either of the screws causes the rubber bands to travel horizontally back and forth over the screw threads. The preferred location is having the sight pin points centered between the flexible members so as to "bracket" the pin. The drive screws can be fixed by tightening an Allen head socket set screw on each.

In another embodiment, a single band may be used after removing one band and aligning the remaining band in the center of the pin aim point, tightening the set screws, and then adjusting the sight pins about 5/16" away from the bow to make a cross-hair sight. A special pin having a slender elongated section is provided to perform this horizontal "cross-hair" function. This pin consists of a standard No. 8-32 threaded pin about 2" in length with a straight pin of about 5/8" length and 0.03" diameter (straight pin size) extending from the end of the threaded section. The straight pin has a colored bulb at the end for use as a pin sight. As an alternate, the pin may be removed and a horizontal band installed between the vertical pin guard post and the bracket. The vertical pin guard is notched at typically 1/32" intervals to maintain the rubber band in the selected horizontal positions.

FIG. 1 is a side elevation of the bow pin sight;

FIG. 2 is an end view taken along line 2--2 of FIG. 1;

FIG. 3 is a side elevation of a "boxed" aim point;

FIG. 4 is a side elevation of a further embodiment of the invention;

FIG. 5 is a side elevation of another embodiment of the invention;

FIG. 6 is a side elevation of the bow sight, properly aimed;

FIG. 7 is a side elevation of the bow sight, improperly aimed; and

FIG. 8 is a side elevation of the bow sight, improperly aimed.

FIG. 1 illustrates the preferred embodiment of the pin guard bow sight generally indicated as 10. The pin guard 12 has an upper and lower collet 14 held in place over the pin guard 12 by Allen set screws 16. Adjacent the collets are a pair of drive screws 18 also having a longitudinal bore to allow the pin guard to pass through and allowing rotation of the drive screws 18. Each drive screw 18 is retained in position by a second pair of collets 20. A pair of vertical flexible members (rubber bands) 22 is installed over the drive screws at a distance of about 3/16", or 5 threads. Rotation of knurled portion 24 of the drive screws 18 causes the rubber bands 22 to travel left or right over the threaded portion 26. The pin guard 12 is attached to a bow bracket (not shown), well known in the art, by fasteners, such as nuts, lockwashers, etc. (not shown) and threads 30 of the pin guard 12. Also mounted by threads to the bracket are the sight pins 32 having an elongated aim point and pin head 34. The vertical rubber bands 22 are adjusted so that pin head 34 is centered between the bands and then secured by tightening set screws 36.

FIG. 2 illustrates an end view of the pin guard showing grooves 40 on the vertical face of pin guard 12. The function of these will be seen by referring to FIG. 3, an embodiment of the present invention. This figure shows a pair of horizontal rubber bands 42 installed over pin guard 12 in the grooves 40. The opposite end of the band 42 goes around the bow bracket (not shown) and the bands 42 are adjusted to center the pin head within "box" 44. They are easily relocated to a different range sight pin, i.e. upper or lower, by moving to a higher or lower groove.

FIG. 4 illustrates a cross-hair type of sight wherein the single rubber band 22 is used in conjunction with pin 32 to form an aim point at 50.

FIG. 5 illustrates a further embodiment of the crosshair sight using pin 32, band 22, and horizontal bands 42 to bracket the pin and aim point 50 with the bands 42.

A novel feature of the sight can be seen in FIGS. 6, 7, and 8 that is due to the thread pitch of drive screw 18. The model shown has a No. 10-24 thread 26, i.e. 24 threads per inch; and because rubber bands 22 span one-half a thread, the back portion of rubber band 22 (behind the drive screw) is a little less than 1/32 of an inch to the left of the front portion of the band at the upper screw 18, as illustrated at 60. At the bottom 62 of the bands, the reverse is true, and the back band portion is less than 1/32" to the right of the front portion.

Referring to FIG. 6, it should be noted that for a properly adjusted sight and an accurately pointed bow at the top 60 and bottom 62 both bands (front and back) will be visible; whereas at center 64, only one band will be visible and this will appear to be a thin line. In this case, the upper 60 and lower portions 62 will appear thicker.

In contrast, referring to FIG. 7, the archer is shooting to the right and the thicker silhouette appears at bottom 66 and thinner silhouette appears at top 68. Finally, when the archer is shooting to the left, the thicker silhouette will appear at top 70 in FIG. 8, and the thin silhouette will appear at bottom 72. Consequently, for highly accurate sighting, such as target shooting, the sight gives indication to the archer of proper or improper aim, i.e. proper aim is illustrated by FIG. 6.

A further advantage of the vertical bands is that they can be lined up with vertical objects, such as trees, target sides, etc., to keep the bow in a vertical position, which is required for accurate shooting.

While a preferred embodiment of the invention has been disclosed, various modes of carrying out the principles disclosed herein are contemplated as being within the scope of the following claims. Therefore, it is understood that the scope of the invention is not to be limited except as otherwise set forth in the claims.