Abstract:
An improved bow sight adjustment mechanism for use with an archery bow is provided. The bow sight adjustment mechanism includes the provision of a dowel pin or similar article disposed between a slide lock and a slide stop to maintain a spaced apart relationship. The dowel pin also extends through the slide with a flexible bushing disposed between the dowel pin and the slide to minimize inadvertent movement of the bow sight adjustment mechanism which could effect the position of the bow sight.

Description:
This application is a Continuation of application Ser. No. 10/210,135 filed Aug. 1, 2002 now U.S. Pat. No. 6,688,008. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to archery accessories. More particularly, though not exclusively, the present invention relates to an adjustable bow sight mechanism for use with a bow for shooting arrows. 
   2. Problems in the Art 
   Bow hunting has gained popularity in recent years. Today, several states sponsor bow hunting seasons for animals such as deer, elk, moose and bear. 
   Archery competitions are also becoming more popular. Archers are judged based upon the accuracy and precision of their shots. 
   Good archery skills are important to both bow hunters and competitive archers. The ability to consistently strike an intended target with an arrow is essential. 
   For hundreds of years archers shot arrows without any particular sighting mechanism. Rather the archer would learn by repetition and feel where to position his bow and arrow in order to hit his or her intended target or prey. This is often referred to as “instinctive shooting.” 
   As an alternative to instinctive shooting, many archers today use some type of sighting mechanism. A typical bow sight usually includes a plurality of sighting pins that are used for alignment purposes. The sighting pins can be adjusted both horizontally and vertically. More than one pin is normally used in order for the archer to sight on targets at different distances. For example, the archer may set one pin for a 15 yard shot and another pin for a 25 yard shot. Varying the height of the pins will account for the projectile motion of the arrow, thus allowing the archer to improve his or her accuracy from various distances. 
   Although bow sights have helped archers and bow hunters improve the accuracy and precision with which they shoot, such sights still suffer from various deficiencies. Most significantly, the pins are difficult and cumbersome to adjust. Often times the sights require the use of Allen wrenches or other tools that are not easy to use in the field and require a great finger dexterity to use. Still further, adjusting the individual pins in this manner can often result in over-adjustment, as fine adjustments in the location of the pins are difficult to achieve. 
   Not surprisingly, others have sought to improve upon bow sights and mechanisms for adjusting the same. For example, U.S. Pat. Nos. 3,579,839 and 4,457,076 generally disclose the use of screw devices or thumb screws that are rotated to adjust a sighting pin in either the horizontal or vertical direction. A plunger or spring-loaded ball is disposed in a surface adjacent the head of the screw such that it projects into a detent on the screw. It is intended that use of such detent mechanisms would avoid the necessity of a separate locking mechanism on the device. Such adjustment devices also suffer from various problems. For instance, there is too much “play” or “give” in the adjustment mechanism such that it overshadows any adjustments to the pins that are made by rotating the thumb screws. A separate locking mechanism is therefore still required to eliminate this inadvertent movement of the bow sight adjustment mechanism. 
   Accordingly, a primary objective of the present invention is the provision of a bow sight adjustment mechanism that can be used without tools and the like and that does not require a separate locking mechanism. 
   A still further feature of the present invention is the provision a bow sight adjustment mechanism that eliminates inadvertent movement of the bow sight without the need for a separate locking mechanism. 
   Another objective of the present invention is the provision of a bow sight adjustment mechanism that is economical to manufacture and durable in use. 
   These and other features become apparent from the following description of the invention. 
   SUMMARY OF THE INVENTION 
   The present invention relates to an improved bow sight adjustment mechanism having a slide lock, a slide stop and a slide mounted between the slide stop and the slide lock on an elongated screw device. The improvement includes the addition of one or more dowel pins or similar rigid member extending between the slide lock and the slide stop. The slide, which moves about the length of the thumb screw in response to a rotation of the screw, also includes an aperture that allows the dowel pin to pass through the slide with a flexible bushing positioned between the dowel pin and the slide. The flexible bushing, preferably made of nylon, effectively absorbs any looseness or “slop” between the dowel pin and the slide, thereby minimizing inadvertent movement of the adjustment mechanism. 
   The present invention also includes a new method for sighting a bow having a sighting element with a plurality of pins. The method generally includes providing a bow, providing an adjustable bow, sight mechanism as described previously, attaching the bow sight adjustment mechanism to a bow, adjusting the plurality of pins individually to achieve a desired spacing of shots for different distances, and then adjusting the sighting element by rotating the screw devices that cause adjustment in the horizontal and vertical directions. Those skilled in the art will appreciate that once the archer determines the appropriate spacing for the pins for various distance intervals, the adjustment mechanism can be used to fine tune or more precisely adjust all of the pins at the same time. Of course, the bow sight adjustment mechanism also avoids the use of Allen wrenches and similar tools, as well as the need for a separate locking mechanism on the device. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which: 
       FIG. 1  is a perspective view of a preferred embodiment of a bow sight adjustment mechanism of the present invention. 
       FIG. 2  is a top elevational view of the bow sight adjustment mechanism shown in  FIG. 1  as attached to an archery bow shown in dashed lines. 
       FIG. 3  is a perspective view of a sight mount. 
       FIG. 4  is a perspective view of a slide lock. 
       FIG. 5  is a perspective view of a plunger. 
       FIG. 6  is a perspective view of a thumb screw. 
       FIG. 7  is a perspective view of a slide stop. 
       FIG. 8  is a perspective view of a L-shaped slide. 
       FIG. 9  is a perspective view of a flexible bushing. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention will be described as it applies to its preferred embodiment. It is not intended that the present invention be limited to the described embodiment. It is intended that the present invention cover all modifications and alternatives which may be included within the spirit and scope of the invention. 
   Referring now to the drawings, a preferred embodiment of the bow sight adjustment mechanism  10  is show in FIG.  1 . The bow sight adjustment mechanism  10  generally includes a sight mount  11 , horizontal adjustment mechanism  12  and vertical adjustment mechanism  14 . 
   The horizontal adjustment mechanism  12  includes a portion of the sight mount  11  (also referred to as a slide) that is disposed between a slide lock  16  and a portion of a L-shaped member  18  (also referred to as a slide stop). The slide lock  16  and slide stop  18  are held in a spaced-apart relationship by two dowel pins  26  that are pressed into the slide lock  16  and slide stop  18  about their opposite ends. As will be explained further, the dowel pins  26  provide stability in addition to maintaining the slide lock  16  and slide stop  18  in a spaced-apart relationship. A thumb screw  20  having an elongated shaft  22  and a bead  24  runs through the slide lock  16 , the sight mount  11 , and the slide stop  18 . The shaft  22  of the thumb screw  20  is held at its terminal end by a hexnut  28 . Rotating the head  24  of the thumb screw  20  causes the slide portion  15  of the sight mount to move along the longitudinal axis of the screw  22  and dowel pins  26 . Note that flexible bushings  25  are disposed between the dowel pins  26  and the slide portion  15  of the sight mount  11 . The purpose of the flexible bushings  25  is to allow the slide portion  15  to easily move along the longitudinal axis of the dowel pins  26  while filling in any gaps that may exist therebetween, which can result in inadvertent movement or “play” in the adjustment mechanism. The flexible bushings are key to the present invention, as they help ensure that the bow sight adjustment mechanism  10  does not have significant internal movement. 
   The vertical adjustment mechanism  14  similarly includes a slide lock  30 , a slide stop  32 , and a portion of the L-shaped member  18  that acts as a slide. The vertical adjustment mechanism includes dowel pins  42  that extend between the slide lock  30  and the slide mount  32 . The vertical adjustment mechanism  14  also includes a thumb screw  34  with an elongated shaft  36  and a head  38  as previously described. The terminal end of the elongated screw  36  is again held in place by means of a hexnut  40 . Flexible bushings  25  are also disposed between the L-shaped member  18  (or slide for purposes of the vertical adjustment mechanism  14 ) and the dowel pins  42 . The slide lock  30  and slide stop  32  also include apertures  41  for mounting a sighting element which generally includes a plurality of pins (not shown). 
   It should be understood that the present invention is not limited to the use of dowel pins, but can include other rigid spacing elements. 
   It can be appreciated that the L-shaped member  18  acts as a slide stop in the horizontal mechanism  12  and a slide in the vertical adjustment mechanism  14 . That is, the slide lock for the horizontal adjustment mechanism  12  and the slide for the vertical adjustment mechanism  14  are integrally formed. 
     FIG. 2  illustrates the preferred embodiment of the bow sight adjustment mechanism  10  as attached to a bow  44 . It should be understood that the bow sight adjustment mechanism  10  can be easily adapted for attachment to any type of bow. 
   The sight mount  11  is shown in more detail in FIG.  3 . The sight mount  11  includes a slide portion  15  as discussed previously. The slide portion  15  includes a threadable aperture  54  for receiving the elongated screw  22  of the thumb screw  20 . The slide portion  15  of the sight mount  11  also includes two apertures  52  that allow the dowel pins  26  to pass therethrough. The sight mount  11  further includes two legs  50  that are bored to enable screws to pass therethrough for attachment to the bow  44 . 
   One of the slide locks  16  is shown in FIG.  4 . The slide lock  16  includes an aperture  58  to accommodate the screw  22  of the thumb screw  20 . The slide lock also includes two additional apertures  60  in which the ends of the dowel pins  26  are secured by a pressed fit. 
   The slide lock  16  includes a surface  56  with a small aperture  62  bored into the surface adjacent the aperture  58 . The small aperture  62  is provided for housing a spring-loaded plunger  64  or similar article (see FIG.  5 ). The spring-loaded plunger  64  is intended to fit into one of the detents  23  on the underside of the head  24  of the thumb screw  20  (see FIG.  6 ). This combination of elements allows for adjustments to be made in certain increments. In addition, this spring-loaded plunger  64  and thumb screw  20  in combination with the flexible bushings in the slide effectively limit unwanted or inadvertent movement of the bow sight adjustment mechanism  10 , obviating the need for a separate locking mechanism. 
   One of the slide stops  32  is shown in FIG.  7 . It generally includes an aperture  70  for receiving the elongated screw  36  of the thumb screw  34 . Additional apertures  68  are also provided for securing the dowel pins  42  as discussed previously. An additional aperture  41  is provided for mounting a sighting element. 
   The L-shaped member  18  is shown in FIG.  8 . As discussed previously, the L-shaped member acts as both a slide stop in the horizontal adjustment mechanism  12  and as a slide for the vertical adjustment mechanism  14 . The L-shaped member  18  includes apertures  76  and  80  for receiving the dowel pins  26  and  42 , respectively. Apertures  78  and  82  are also provided for receiving the screw device. Aperture  82  is of course threaded to enable the L-shaped member  18  to travel along the longitudinal axis of the screw  36 . 
     FIG. 9  shows the flexible bushing  25  in greater detail. It has been found that nylon is the preferred material for the flexible bushing  25 . A brass bushing has also been found suitable for various applications. 
   The bow sight adjustment mechanism  10  is easy to use. Once attached to the bow, the preferred method of sighting or adjusting the pins of the sighting element follows. First, it is important that the individual pins be spaced apart at an appropriate distance so that the archer can be assured that the pins cover a certain spread. For example, three pins may be sighted at five yard intervals therebetween. Once the individual pins are sighted then the sighting element, including all of the pins, can be adjusted using the horizontal and vertical adjustment mechanism ( 12  and  14 ). As explained previously, the combination of the spring-loaded plungers  64 , head screws  24  and  38  with detents  23 , dowel pins  26  and  42 , and flexible bushings  25  helps to prevent unwanted or inadvertent movement of the adjustment mechanism due to “slop” or “play” between parts in the mechanism. 
   The primary parts of the bow sight adjustment mechanism are preferably made of steel. However, other high strength materials can also be used. 
   A general description of the present invention as well as a preferred embodiment of the present invention has been set forth above. Those skilled in the art to which the present invention pertains will recognize and be able to practice additional variations in the structure and method described which fall under the teachings of this invention. Accordingly, all such modifications and additions are deemed to be within the scope of the invention which is to be limited only by the claims appended hereto.