Abstract:
A bow sight that utilizes fiber optic wave guides as a basis for collecting ambient light and providing multiple sighting spots within the archer&#39;s field of view. The terminal ends of the fiber optic wave guides are positioned so as to have images thereof reflected on a moveable reflective plane (objective optic) within the bow sight. The multiple aiming spots thus reflected in the bow sight provide the archer with sighting spots for targets over a range of distances. Each of the individual fiber optic wave guides collects ambient light and terminates in a terminal block that may be varied in its position so as to individually adjust the reflected image of the aiming spot. Various mechanisms within the fiber optic terminal block for adjusting the position of the ambient light wave guide are also described. The bow sight provides the advantages of multispot ambient light fiber optic systems with the advantages of reflective (reflex) sighting systems.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under Title 35 United States Code §119(e) of U.S. Provisional Application No. 60/936,121; Filed: Jun. 18, 2007, the full disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to sighting mechanisms for use in conjunction with archery bows. The present invention relates more specifically to bow sights that use illuminated spots to facilitate the aiming of an archery bow at targets over a variety of distances. 
     2. Background of the Invention 
     A number of devices have been developed to facilitate the aiming of an archery bow at a target positioned over a range of distances from the archer. The nature of archery is such that relatively small variations in distance to a target require relatively significant variations in the angle at which the archer holds the bow and aims towards the target. Whereas a distance difference of one hundred yards may merit little change in the aiming angle for a rifle, such distance variations in archery required a much more significant change in the aiming angle. Sighting devices designed for rifles do not translate well into sights suitable for bows. 
     Many sighting devices for archery have been developed in recent years that utilize light image aiming spots that are positioned within the archer&#39;s field of view. In general, such sights either provide a direct view of one end of a fiber optic light guide or provide a reflected image of an LED or other light source. The view produced in either case is typically positioned within a ring that forms the bow sight through which the archer aims. Fiber optic light wave guides are typically positioned within the field of view and extend to one side where they are arranged so as to either gather light from ambient sources or to connect to a small electrically powered light source such as an LED. Such designs provide the ability to individually adjust the position of each of the spots thus created within the bow sight. 
     Other efforts in the past have focused on providing electrical light sources either directly in the bow sight (in place of the fiber optic light wave guides) or positioning electrical light sources in such a manner that a reflection of the light source is directed towards the archer through the bow sight. What has not been achieved in the prior art is a bow sight that combines the advantages of a fiber optic based system utilizing ambient light with the advantages of a reflective bow sight system that eliminates the need to directly position light sources or light guides within the field of view. The present invention provides such a solution to the problem of an efficient, adjustable, and inexpensive bow sight. 
     Other efforts in the past have included the following patents and patent applications: 
     U.S. Pat. No. 5,090,805 issued to Stawarz on Feb. 25, 1992 entitled Bow Sight with Projected Reticule Aiming Spot. 
     U.S. Pat. No. 5,383,278 issued to Kay on Jan. 24, 1995 entitled Wide Field of View Reflex Sight for a Bow. 
     U.S. Pat. No. 5,653,034 issued to Bindon on Aug. 5, 1997 entitled Reflex Sighting Device for Day and Night Sighting. 
     U.S. Pat. No. 5,231,765 issued to Sherman on Aug. 3, 1993 entitled Illuminated Sight Having a Light Collector Serving a Fiber Optic. 
     U.S. Pat. No. 5,394,615 issued to Hoppe et al. on Mar. 7, 1995 entitled Light Archery Sight. 
     U.S. Pat. No. 5,634,278 issued to London on Jun. 3, 1997 entitled Bow Sight. 
     U.S. Pat. No. 5,813,159 issued to Kay et al. on Sep. 29, 1998 entitled Wide Field of View Reflex Gunsight. 
     U.S. Pat. No. 5,914,775 issued to Hargrove et al. on Jun. 22, 1999 entitled Triangulation Rangefinder and Sight Positioning System. 
     U.S. Pat. No. 6,725,854 issued to Afshari on Apr. 27, 2004 entitled Illuminated Sight Pin. 
     U.S. Patent Application Publication No. US 2006/0254065 A1 (Grace) published on Nov. 16, 2006 entitled Archery Bow Sight. 
     U.S. Pat. No. 5,619,801 issued to Slates on Apr. 15, 1997 entitled Fiber Optic Pin Sight for a Bow. 
     U.S. Patent Application Publication No. US 2006/0150429 A1 (Khoshnood) published on Jul. 13, 2006 entitled Ambient Light Collecting Sight Pin for a Bow Sight. 
     The full disclosures of each of the issued U.S. Patents and the Published Applications listed above are incorporated in their entirety herein by reference. 
     SUMMARY OF THE INVENTION 
     The present invention provides a bow sight that utilizes fiber optic wave guides as a basis for collecting ambient light and projecting multiple aiming spots within the archer&#39;s field of view. Rather than positioning the terminal end of the fiber optic wave guides directly in the field of view (as well as the required support structures), the wave guide terminal ends are positioned so as to have images thereof reflected on a moveable reflective objective optic within the archer&#39;s field of view. The multiple aiming spots thus reflected in the bow sight provide the archer with sighting spots for targets over a range of distances. 
     Each of the individual fiber optic wave guides collects ambient light and terminates in a terminal block that may be varied in its position so as to individually adjust the reflected image of the aiming spot. Various mechanisms for adjusting the position of the ambient light wave guides are also described. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top plan view of a first embodiment of the complete bow sight system of the present invention. 
         FIG. 2  is a side plan view of the first embodiment of the complete bow sight system of the present invention shown in  FIG. 1 . 
         FIG. 3  is an end view of the first embodiment of the bow sight system of the present invention as seen from the point of view of the archer with the mounting plate components removed for clarity. 
         FIGS. 4A through 4C  are orthogonal plan views of an alternative embodiment of the bow mounting plate component of the present invention. 
         FIGS. 5A through 5C  are orthogonal plan views of a bow sight tube bracket of the preferred embodiment of the present invention. 
         FIGS. 6A and 6B  are orthogonal plan views of a bow sight tube ring component of the preferred embodiment of the present invention. 
         FIGS. 7A and 7B  are orthogonal plan views of a retention ring for the sight tube component of the present invention. 
         FIGS. 8A through 8C  are orthogonal plan views of a fiber optic terminal block structure of the preferred embodiment of the present invention, with  FIG. 8B  being an assembly view. 
         FIG. 9  is a cross-sectional view of a first preferred embodiment of the fiber optic channel and terminal block structure of the present invention. 
         FIG. 10  is a detailed view of a first preferred embodiment of the fiber optic terminal block assembly of the present invention. 
         FIGS. 11A and 11B  are orthogonal views of an alternate preferred embodiment of the fiber optic terminal block adjustment assembly of the present invention. 
         FIGS. 12A and 12B  are orthogonal views of a second alternate preferred embodiment of the fiber optic terminal block adjustment assembly of the present invention. 
         FIGS. 13A and 13B  are orthogonal views of a third alternate preferred embodiment of the fiber optic terminal block adjustment assembly of the present invention. 
         FIG. 14  is a perspective view of an alternative embodiment of the complete bow sight system of the present invention. 
         FIG. 15  is an orthogonal side plan view of an alternative embodiment of the complete bow sight system of the present invention. 
         FIG. 16  is an orthogonal top plan view of an alternative embodiment of the complete bow sight system of the present invention. 
         FIG. 17  is a detailed perspective exploded view of the fiber optic housing of an alternative embodiment of the system of the present invention. 
         FIG. 18  is an orthogonal rear plan view of an alternative embodiment of the complete bow sight system of the present invention. 
         FIGS. 19A through 19C  are orthogonal views of the bow mounting plate component of an alternate preferred embodiment of the present invention. 
         FIGS. 20A through 20C  are orthogonal views of the vertical adjustment clamp component of an alternate preferred embodiment of the present invention. 
         FIGS. 21A through 21C  are orthogonal views of the lens bracket component of an alternate preferred embodiment of the present invention. 
         FIGS. 22A through 22C  are orthogonal views of the main beam component of an alternate preferred embodiment of the present invention. 
         FIGS. 23A through 23C  are orthogonal views of the fiber optic holder rack component of an alternate preferred embodiment of the present invention. 
         FIGS. 24A through 24D  are orthogonal views of a typical fiber optic holder component of an alternate preferred embodiment of the present invention. 
     
    
    
     The various figures include referenced elements and components that are common and which include the following referenced component: 
     
       
         
               
               
             
           
               
                   
               
             
             
               
                 10 
                 bow stock cross section (dashed outline) 
               
               
                 12 
                 bow mounting plate 
               
               
                 14 
                 clamp screw (horizontal adjustment) 
               
               
                 16 
                 clamp (vertical) 
               
               
                 18 
                 clamp screw (vertical adjustment) 
               
               
                 20 
                 sight stock 
               
               
                 22 
                 projection stock 
               
               
                 24 
                 fiber optic channel 
               
               
                 26 
                 channel cover plate 
               
               
                 28a-28d 
                 fiber optic terminal blocks (four spot version) 
               
               
                 30a-30d 
                 fiber optic adjustment set screws (four spot version) 
               
               
                 32a-32d 
                 fiber optic wave guides (four spot version) 
               
               
                 34 
                 light receptor coil assembly 
               
               
                 36 
                 coil bracket 
               
               
                 38 
                 sight base assembly 
               
               
                 40 
                 sight tube (sight ring) 
               
               
                 42 
                 reflective objective optic 
               
               
                 44 
                 optic retainer ring 
               
               
                 46 
                 sight pivot screw 
               
               
                 48 
                 sight adjustment screw 
               
               
                 50a-50d 
                 aiming spot images 
               
               
                 52 
                 bow stock mounting apertures 
               
               
                 60 
                 alternate embodiment bow sight system 
               
               
                 62 
                 bow mounting plate 
               
               
                 64 
                 vertical adjustment clamp 
               
               
                 66 
                 lens bracket 
               
               
                 68 
                 sight tube with optic 
               
               
                 70 
                 main beam 
               
               
                 72 
                 fiber optic holder rack 
               
               
                 74 
                 right fiber optic holder shell 
               
               
                 76 
                 left fiber optic holder shell 
               
               
                 80 
                 fiber optic holder (typical) 
               
               
                 82 
                 mounting holes 
               
               
                 84 
                 fiber light gathering slots 
               
               
                 86 
                 fiber optic adjustment view window 
               
               
                 88 
                 mounting plate clamp tightening screw 
               
               
                 90 
                 sight tube mounting screw 
               
               
                 92 
                 horizontal fiber optic image adjustment screw 
               
               
                 94 
                 vertical adjustment clamp tightening screw 
               
               
                 96 
                 sight tube mounting screws 
               
               
                 98 
                 fiber optic passage 
               
               
                 100  
                 fiber optic holder adjustment screw 
               
               
                 102  
                 fiber optic channel aperture 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is generally described by the referenced Drawing figures attached.  FIG. 1  discloses the manner in which the assembly of the invention is attached to a bow stock and provides a first preferred embodiment of the invention. In general the invention comprises an assembly of components that provide multiple adjustable aiming spots within the field of view of the archer. The ambient light for the aiming spots is gathered in an assembly of fiber optic coils held on a bracket to one side of the bow sight. The light is carried by the fiber optic wave guides along the bracket frame of the bow sight to a fiber optic terminal block adjustment assembly. The light is then projected onto an angled partially reflective objective optic where it is reflected into the archer&#39;s field of view. The multiple aiming spots are positioned vertically one above the other and allow the archer to place an aiming spot on the target according to an estimate range to the target. That is, a target that is close might require use of the highest aiming spot (lowering the angle of the bow) in the field of view while a very distant target might require use of the lowest aiming spot (lifting the angle of the bow). 
     The side to side placement of the aiming spots in the field of view is achieved by way of a pivoting sight tube bracket. The elevation (vertical adjustment) of the individual aiming spots may be varied according to one of a number of different mechanisms within the fiber optic terminal block assembly as disclosed in the attached Drawing figures. Four (4) spot and five (5) spot versions of the preferred embodiments are shown although those skilled in the art will recognize that the present invention lends itself to use in conjunction with systems that incorporate from three (3) to as many as seven (7) or more aiming spots. It is preferable to use different colored fiber optic wave guides for the different aiming spots to facilitate the choice of an appropriate spot for a particular range. 
       FIG. 1  is a top plan view of a first embodiment of the complete bow sight system of the present invention. Bow stock  10  is shown in cross section (dashed outline) and provides the support for bow mounting plate  12 . Clamp screw (horizontal adjustment)  14  tightens the clamp component of bow mounting plate  12  onto clamp (vertical)  16 . Likewise, clamp screw (vertical adjustment)  18  tightens the clamp component of clamp (vertical)  16  onto sight stock  20 . 
     Sight stock  20  supports projection stock  22  and integrates fiber optic channel  24  with channel cover plate  26 . Fiber optic terminal blocks (four spot version)  28   a - 28   d  incorporate fiber optic adjustment set screws (four spot version)  30   a - 30   d  projection stock  22 . Fiber optic wave guides (four spot version)  32   a - 32   d  carry light from the light receptor coil assembly  34  mounted on the coil bracket  36  which is positioned on the sight base assembly  38 . 
     Sight tube (sight ring)  40  integrates and holds reflective objective optic  42  with optic retainer ring  44 . The angle of sight tube  40  can be adjusted using sight pivot screw  46  and sight adjustment screw  48 . 
       FIG. 2  is a side plan view of the first embodiment of the complete bow sight system of the present invention shown in  FIG. 1  with the same referenced components identified therein. 
       FIG. 3  is an end view of the first embodiment of the bow sight system of the present invention as seen from the point of view of the archer with the mounting plate components removed for clarity. In this view the aiming spot images  50   a - 50   d  can be seen. 
       FIGS. 4A through 4C  are orthogonal plan views of the sight stock component of the present invention. In this view the manner of attachment of the remaining components (as shown in  FIGS. 1 &amp; 2 ) can be seen. 
       FIGS. 5A through 5C  are orthogonal plan views of a bow sight tube bracket of a preferred embodiment of the present invention. 
       FIGS. 6A and 6B  are orthogonal plan views of a bow sight tube ring component of a preferred embodiment of the present invention. 
       FIGS. 7A and 7B  are orthogonal plan views of a retention ring for the sight tube component of the present invention. 
       FIGS. 8A through 8C  are orthogonal plan views of a fiber optic terminal block structure of the preferred embodiment of the present invention, with  FIG. 8B  being an assembly view. 
       FIG. 9  is a cross-sectional view of a first preferred embodiment of the fiber optic channel and terminal block structure of the present invention. 
       FIGS. 10 ,  11 A &amp;  11 B,  12 A &amp;  12 B, and  13 A &amp;  13 B are detailed views of alternate preferred embodiments of the fiber optic terminal block assembly of the present invention. 
     DETAILED DESCRIPTION OF ALTERNATE PREFERRED EMBODIMENT 
       FIG. 14  is a perspective view of an alternative embodiment of the complete bow sight system of the present invention. In this view alternate embodiment bow sight system  60  is shown to include bow mounting plate  62 , vertical adjustment clamp  64 , lens bracket  66 , sight tube with optic  68 , main beam  70 , and fiber optic holder rack  72 . Fiber optic holder rack  72  is shown to include right fiber optic holder shell  74  and left fiber optic holder shell  76 . Together these components support and position fiber optic holders  80 . 
       FIG. 15  is a side plan view of an alternative embodiment of the complete bow sight system of the present invention. In this view mounting holes  82  in bow mounting plate  62  are disclosed. Fiber optic light gathering slots  84  which carry the fiber optics for the system are shown integrated into main beam  70 . Fiber optic adjustment window  86  allows the user to view the vertical adjustment of the fiber optic light guides and therefore of the light images in the sight tube. 
       FIG. 16  is a top plan view of an alternative embodiment of the complete bow sight system of the present invention. In this view mounting plate clamp tightening screw  88  is shown as the means for clamping bow mounting plate  62  to vertical adjustment clamp  64 . Sight tube mounting screw  90  attaches sight tube  68  to main beam  70 . Horizontal fiber optic adjustment screw  92  is position to provide a means for moving fiber optic holder rack  72  side to side, thereby adjusting the horizontal position of the light spots on the optics. These components are shown in greater detail in  FIGS. 17 &amp; 18 . 
       FIGS. 19A through 19C  are orthogonal views of the bow mounting plate  62  component of an alternate preferred embodiment of the present invention. Mounting holes  82  are seen clearly in this view. 
       FIGS. 20A-20C  are orthogonal views of the vertical adjustment clamp  64  component of an alternate preferred embodiment of the present invention. Vertical adjustment clamp tightening screw  94  is seen in this view. 
       FIGS. 21A-21C  are orthogonal views of the lens bracket  66  component of an alternate preferred embodiment of the present invention. Sight tube mounting screws  96  are seen in this view. 
       FIGS. 22A-22C  are orthogonal views of the main beam  70  component of an alternate preferred embodiment of the present invention. The manner of routing the fiber optic light guides around the sides and edges of the main beam  70 , as well as fiber optic passage  98 , are shown. 
       FIGS. 23A-23C  are orthogonal views of the fiber optic holder rack  72  component of an alternate preferred embodiment of the present invention. 
       FIGS. 24A-24D  are orthogonal views of a typical fiber optic holder  80  component of an alternate preferred embodiment of the present invention. In this view, fiber optic holder adjustment screw  100  and fiber optic channel aperture  102 , as integrated in each of the fiber optic holders  80 , are shown. 
     The changing the configuration from side mounted fibers in the first preferred embodiment to mounting them vertically provides certain additional advantages. When the orientation is vertical with a side configuration, the virtual image generated by the concave lens can sometimes be skewed and as a result may not accurately track the arrow point of impact due to the extreme side angle of reflection. If this is the case, the second preferred embodiment provides an orientation where the fiber holders are located vertically and back in an adjustable housing. 
     The entire adjustable housing can move side to side with an adjustment screw as described above. This arrangement allows the archer to sight the bow with the overall sight adjustments and then center the dots in the lens with the housing adjustments. Each fiber holder is still individually adjustable vertically, to sight in at the varying distances. 
     The fiber optic fibers are run out of the housing and through the grove in the main support beam. They are run along the top, side and front of this beam to gather ambient light from all directions. In the preferred embodiment, these fibers are held in clear plastic tubing which may be adhered to the main beam. 
     The lens in the second preferred embodiment is a concave semi-reflective lens. Depending on availability, a 4-base circular lens with a red semi-reflective coating may be used (the type often used on sunglasses). The fibers must be placed at a specific distance in order to generate the proper virtual image in the lens. This distance is critical to track the point of impact. The light source must be at a precise proportion to the focal length of the lens. The resulting virtual image is greatly magnified and perfectly in line with the point of impact. 
     Depending on the diameter of the fiber optic fiber the above mentioned magnification can cause some problems. With a fiber of 0.020″ the lens magnifies about 3 times and the resulting dot is too big in the view of the archer. The large image is not accurate enough at the longer ranges. One solution is to countersink a 0.023″ hole into the holder and then drill out a 0.010″ hole for the light to shine through. This cuts the fiber image in half so that it is usable to the archer. This may be a practical approach to reducing the size of the light spot image when necessary. 
     Although a specific advantage of the present invention is its ability to gather ambient light, it is adaptable for use in conjunction with artificial light sources. The basic system of the present invention may be used in conjunction with standard bow sight mounts that provide horizontal and vertical support adjustments. In addition, the system allows for use on either right or left handed bows by simply inverting the assembly. The system does not interfere with the arrow or the arrow rest in any configuration and generally adds little to the weight of the bow. The various components of the system of the present invention are easily assembled and disassembled as needed for adjustment, maintenance, and/or replacement. The same basic frame, sight tube, and light gathering assembly, may be used with any of the various described fiber optic terminal block assemblies. 
     The system of the present invention combines the advantages of an ambient light fiber optic bow sight with the advantages of a reflex bow sight. Specifically, the bow sight of the present invention requires no electrical power and collect sufficient ambient light to provide easily visible aiming spots. The system utilizes multiple fiber optic wave guides in order to provide multiple, independently adjustable, aiming spots. The system uses a reflective objective optic to reflect an image of the bright ends of the fiber optics within the field of view. Unlike most systems that utilize fiber optic wave guides, the present invention does not clutter or obstruct the field of view with support structures or other components required by non-reflex systems.