Patent Abstract:
A sighting device replicates the spread pattern of pellets exiting the barrel of a shotgun. The sighting device includes a light source (preferably a laser) and a power source connectable to the light source. The device may also include a mount to attach the sighting device to a shotgun. The sighting device preferably projects a circular pattern of individual light beams wherein the circumference of the circular pattern increases as the light beams move farther from the sighting device to replicate the spread of shotgun pellets. The sighting device may also project a beam of light in the center of the pattern.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims priority to U.S. patent application Ser. No. 13/707,312, now U.S. Pat. No. 8,844,189 entitled SIGHTING DEVICE REPLICATING SHOTGUN PATTERN SPREAD, filed on Dec. 6, 2012, the disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a light-emitting sighting device, particularly a laser, that can be mounted on a shotgun and that emits a pattern that replicates the spreading pattern of shotgun pellets after being fired. The disclosures of U.S. Pat. No. 8,127,485 to Moore et al. and U.S. application Ser. No. 12/160,213 to Moore et al. are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     It is known to utilize a light beam, such as a laser beam, as a sighting aid for guns. Lasers are the preferred means of generating light beams for weapon sighting because they have comparatively high intensity and can be focused into a narrow beam with a very small divergence angle so they produce a small, bright spot on a target. If mounted properly on a gun, the laser projects a beam of laser light in a direction generally parallel to the gun&#39;s bore. When the light beam and bore are properly aligned, the bullet (or other projectile) will strike, or strike very close to, the location of the light beam projected on a target. Such laser sighting devices can be used to target a weapon when using live ammunition or to simulate the actual firing of a weapon whereby the laser beam strikes a target to show where a live round would land. 
     It was known to use a laser connected to a gun to generate a pattern of light, such as a circular pattern formed by multiple laser light beams with a single laser light beam in the center. The problem with this device is that the light beams were projected outward its an exaggerated angle. Thus, the device may have been useful for centering and aiming a gun firing a bullet, but did not replicate the spread pattern of shotgun pellets after being fired. Thus, such a device did not accurately frame a target with respect to where shotgun pellets would land. This was especially true the farther the target was from the device, since the farther away the target, the greater the shotgun pellet spread. 
     SUMMARY OF THE INVENTION 
     The invention is a sighting device for a shotgun (hereafter, sometimes referred to as “sighting device” or “device”), or for a structure replicating a shotgun. A shotgun and device replicating a shotgun, which might be used for laser beam target practice are collectively referred to herein as “shotgun.” The sighting device includes a light source, which is most preferably a laser. The sighting device may be mounted on or included as part of a shotgun and can be used to aim the shotgun before firing a live round of ammunition, or to simulate the actual firing of a shotgun by the light emanating from the light source showing the area in which pellets from a live shotgun round would land. Once activated, light beams from the sighting device are projected outwardly, preferably in a circular pattern, that expands as the light beams travel farther from the sighting device, thereby replicating the spread pattern of pellets fired from a shotgun. The sighting device preferably includes a laser as the light source, a power source connectable to the laser, and a mount for mounting the sight to the shotgun. In one embodiment, the sighting device is attached to a picatinny rail of the shotgun, although it can be attached to or included as part of a shotgun in any suitable manner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of an embodiment of the present invention. 
         FIG. 1A  is a front view of the assembled device shown in  FIG. 1 . 
         FIG. 1B  is a top view of the device shown in  FIGS. 1 and 1A . 
         FIG. 1C  is a rear view of the device shown in  FIGS. 1-1B  but without the backing or the button yet attached. 
         FIG. 1D  is a rear view of the device shown in  FIGS. 1-1C  when fully assembled. 
         FIG. 1E  is a rear view of the device shown in  FIGS. 1-1D  without the backing or the integrated circuit board and showing the laser module biased to one side (the laser biasing spring also is not shown). 
         FIG. 1F  is a partial, cross-sectional top view of a light source biased to one side of the biasing cone (or light source adjustment apparatus). 
         FIG. 2  is a side, perspective view showing the embodiment of  FIG. 1 . 
         FIG. 3  is an alternate side, perspective view of the embodiment shown in  FIGS. 1 and 2 . 
         FIG. 4  is a rear, top, perspective view of the embodiment shown in  FIGS. 1-3 . 
         FIG. 5  is a front, top, perspective view of the embodiment shown in  FIGS. 1-4 . 
         FIG. 6  is a rear, perspective view of a device according to the invention. 
         FIG. 7  shows an embodiment of a sighting device according to the invention that is mounted to the picatinny rail of a shotgun. 
         FIG. 8  shows an alternate embodiment of a sighting device of the present invention. 
         FIG. 9  shows a bottom, rear perspective view of the sighting device of  FIG. 8 . 
         FIG. 10  shows a bottom, front perspective view of the sighting device of  FIG. 8 . 
         FIG. 11  shows a rear view of the sighting device of  FIG. 8 . 
         FIG. 12  shows a front view of the sighting device of  FIG. 8 . 
         FIG. 13  shows an exploded view of the sighting device of  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Turning now to the drawings where the purpose is to describe a preferred embodiment of the invention and not to limit same,  FIGS. 1-7  show a preferred embodiment of a sighting device  10  according to the invention. Device  10  as shown is a laser sight, but could be any structure that includes a light source and one or more power sources connectable to the light source and that can simulate the spread pattern of shotgun pellets exiting the barrel of a shotgun. 
     Preferably, device  10  is configured to be mounted on a shotgun  11 , and most preferably on a picatinny rail of the shotgun  11 . A picatinny rail  9  (best seen in  FIG. 7 ) is known in the art and used to connect accessories to gun. As shown, picatinny rail  9  is on the top of the shotgun barrel. 
     Device  10  could also be mounted to or formed in the shotgun in any other suitable, fashion that allows the light source of device  10  to be accurately projected along the longitudinal axis of the shotgun barrel  13 , and/or along the longitudinal axis of a light source  20 . 
     Device  10  includes a light source  20 , a power source  30  and a housing  200  that includes a mount  102 , which as shown has a first leg and a second leg, which are not shown here, but preferably have the same structures as legs  1002 A and  1002 B discussed below, that fit onto picatinny rail  9 . 
     Light source  20  has a first end  20 A (through which light can be emitted), is preferably a visible-light laser module, but could be any light source, including a light emitting diode (“LED”) flashlight (as used herein “flashlight” means any source of visible light other than a laser) or an infra-red light source (such as an infra-red LED or infra-red laser). In the embodiment shown light source  20  is a red-light, 650 nanometer, 3.3 mm diode, visible laser, and the laser module has an overall length of about 14 mm and a diameter of about 4.5 mm. Any suitable laser/laser module may be used, however. A biasing spring  24  is attached to second end  20 B to bias light source  20  towards first end  20 A when device  10  is assembled. Light source  20  includes a diffraction lens (not shown) that converts the single laser beam generated by light source  20  into multiple, individual beams of light. Diffraction lenses are known to those skilled in the art. In embodiments of the present invention, the diffraction lens can be assembled as part of light source  20  or be positioned outside of light source  20 . 
     The multiple light beams generated by the diffraction lens are spread apart so as to define an area between them. The area can be of any suitable shape for replicating the area in which pellets exiting a shotgun would occupy. It is most preferable that the area defined by the multiple light beams is circular, but it could also be triangular, oval, rectangular, hexagonal, octagonal or of any suitable shape. In one preferred embodiment there are at least three light beams defining the area, and most preferably eight beams of light defining the area, even though any number of light beams of three or more can be utilized. Additionally, a complete, uninterrupted pattern of light could be created to form an area between the pattern. 
     The diffraction lens directs each of the multiple beams of light outward with respect to the longitudinal axis of the light source  20 , as shown in  FIG. 7 . In one embodiment each of the multiple beams is directed outward at 1.7 degrees as measured from the longitudinal axis of the laser  20 . Any suitable outward direction may be used, however, and is based on the size and type of shotgun, so that the pattern of pellet spread for that shotgun is accurately replicated. 
     The diffraction lens may also create one or more other light beams inside the area, and preferably creates a single light beam in the center of the area formed by the multiple beams. 
     Power source  30  can be any suitable power source for light source  20 , and is preferably an electric power source and most preferably a portable, electrical power source such as a battery or multiple batteries. The embodiment shown uses four 1.5V silver oxide LR626 batteries  32 , although any suitable batteries or other power source may be used. 
     Device  10  as shown further includes a housing  200 , a light source adjustment apparatus  300 , an integrated circuit board  400 , a backing  500 , and a battery cap  600 . The purpose of housing  200  is to retain light source  20  and power source  30  and mount them to a gun, and to selectively connect power source  30  to light source  20 . Any suitable structure or structures may be used for this purpose. 
     Housing  200  is preferably made of metal injection molded stainless steel (MIM), but could be made of any suitable material, such as another metal (for example, MIM carbon steel or extruded aluminum) or plastic. Housing  200  has a first end  200 A, a second end  200 B and includes a first canister  202  and a second canister  230 . First canister  202  is configured to receive and retain the light source  20  (which is preferably a laser module), which as shown is first positioned in light source adjustment apparatus  300 . Once so positioned, apparatus  300 , with light source  20  inside, is positioned in and retained in canister  202 . 
     As shown, canister  202  has an outer surface  204 , a first rib  206 , a second rib  208 , an inner cavity  210  in which apparatus  300  and light source  20  are retained, and an opening  212  through which the light source  20  can emit light. Canister  202  also includes an aperture  206 A that extends through rib  206  to inner cavity  210  and an aperture  208 A that extends through rib  208  to inner cavity  210 . Each of apertures  206 A and  208 A are configured to receive a moveable screw or screw  225  (hereafter referred to as “set screw” or “set screws,” which are preferably socket-head set screws). The purpose of rib  206  and rib  208  (each of which project outward about 0.075″) are to provide additional area to support set screws  225 . Alternatively, a raised portion (described, for example with respect to device  10 ′, device  1000  and device  2000 ) may be used in place of rib  206  and/or  208 . Other structures may be used for this purpose or no such structure may be used. 
     Second canister  230  as shown is spaced apart from first canister  202  and is configured to receive and retain the power source  30 . Canister  230  as shown has an outer surface  234 , an inner cavity  240 , a first end  242  and a second end  244 . Second end  244  is configured to open in order to add or change power source  30 . In the embodiment shown second end  244  includes internal threads (not shown) that mate with threads on power source retention cap  600  to allow cap  600  to be screwed onto end  244  and screwed off of end  244  in order to add or remove power source  30  from canister  230 . 
     Housing  200  also includes a connective portion  270  that connects first canister  202  and second canister  230 . Connective portion  270  has a bottom surface  272  and a mount  102  attached to or integrally formed with bottom surface  272 . Mount  102  includes the previously described first leg and second leg (not shown here) for connecting to picatinny rail  9 , although any suitable structure or structures may be used for this purpose. 
     A light source adjustment apparatus (or “LSAA”)  300  is for retaining the light source  20  when it is positioned in housing  200  and for assisting in positioning light source  20 . LSAA  300  serves two purposes: (1) it absorbs the recoil of a gun to which device  10  is mounted thereby enabling light source  20  to remain in a relatively stable position, and (2) it enables a user to adjust the position of light source  20 . As shown in  FIG. 1 , LSAA  300  is generally conical with a first, smaller diameter end  302  and a second, large diameter end  304 . It is preferably comprised of an elastomeric material, such as neoprene rubber, of about a 60 Shore A to absorb shock, but can be made of any suitable material. It has an opening  308  configured to receive light source  20 . As previously described, LSAA  300  fits into inner cavity  210  of first canister  202 . Instead of LSAA  300 , the light source  20  may be biased towards set screws  225  (described below) by springs (not shown). 
     When device  10  is assembled, the position of light source  20  can be adjusted utilizing set screws  225 . LSAA  300  is shaped to be biased towards apertures  206 A and  208 A and, as one or both set screws  225  are tightened, the set screw(s) pushes against LSAA  300  and moves it (in this embodiment) either sideways and/or vertically thereby adjusting the position of light source  20 . Alternatively, springs inside cavity  210  bias the light source  20  towards each of the set screws  225 , and as the set screws are tightened, they push against the light source  20  and overcome the force of the springs to move light source  20 . 
     Integrated circuit board  400  is configured to be received and mounted on second end  200 B of housing  200 . The basic purpose of board  400  is to connect the power source  30  to the light source  20  and any suitable structure or device can be used for this purpose. Board  400  is preferably plastic and includes a push button switch  402 , an integrated circuit  404  and two through screw holes  406 . Current is transferred via board  400  to laser module  20 . Board  400  is designed for negative switching wherein power is generated from the negative side of power source  30  (which are batteries in this embodiment) and through spring  24  of light source  20  in this embodiment. Integrated circuit  404  allows for the pulsed delivery of power to light source  20  (preferably about 1,000 cycles per second, and preferably pulsing at a 50% on duty rate) in order to save power and power source life, although the delivery of power need not be pulsed, or can be pulsed in any suitable manner. In this embodiment, the light source has between a 8 and 15 milliamp draw, and most preferably less than a 10 milliamp draw, of current when in use and utilizing the 1,000 pulses per minute delivery of current to light source  20 . 
     A button  450  is of any suitable shape to fit with push button switch  402  and backing  500 , described below. Button  450  is for enabling a user to selectively activate switch  402  thus turning the light source  20  off and on, and any suitable device or structure can be used for this purpose. 
     Backing  500  is preferably plastic and its purpose is to hold integrated circuit board  400  to housing  200  and to protect integrated circuit board  400  and the other components inside of housing  200 . Backing  500  has a first side  500 A configured to fit over canister  202  at end  200 B and a second side  500 B configured to fit over end  242  of canister  230 . It further includes an opening  502  through which button  450  projects so it can be pressed by a user to turn light source  20  on and off, and openings  506  that align with screw holes  406  and screw retainers  250 . Screws  510  are then received through openings  506  and screw holes  406 , and are threaded into retainers  250  to hold device  10  together. 
     Power source retention cap  600  has a threaded end  602  and an end  604  that can be tightened or loosened by a user. The purpose of cap  600  is to selectively open and close second canister  230  to allow power source  30  to be removed or inserted and any structure capable of performing this function can be used. Cap  600  has a cavity  606  that receives a spring  608  to bias batteries  32  away from spring  608 . Spring  608  contacts the positive side of the power source  30  and grounds it to the housing  200  through cap  600 . As explained below, a rubber biasing collar  620  may also be utilized with cap  600 . 
     Turning now to  FIGS. 8-12 , a device  1000  according to an aspect of the invention is shown. The materials, internal structure and function, except for differences in size and shape, and those described herein, are the same as those described for device  10 . Device  1000  includes a housing  1002  that retains a light source  1020  (which is preferably a laser), which is the same as light source  20 , and preferably a diffraction lens, which is the same as the previously described diffraction lens for device  10 . The diffraction lens may be formed as part of light source  1020  or positioned outside of it so that a beam of light exiting light source  1020  is diffracted into multiple beams in the manner previously described and/or subsequently claimed herein. Alternatively, the multiple beams can be created in other ways. 
     An opening  1022  retains a set screw (not shown) that can be used to adjust the position of sighting device  1020  in the sideways direction. Another opening (not shown) is on the top surface  1081  of housing  1002  and retains another set screw (not shown), which can also be used to adjust the position of sighting device  1020  vertically. 
     A power source  1090  is retained within housing  1002  and is preferably three silver oxide 1.5V coin batteries connectable to light source  1020  in the same manner as previously described with respect to sighting device  10 . Housing  1002  includes a removable cap  1004  that covers a cavity that retains the power source. Cap  1004  is held in place by two fasteners  1006 . 
     Housing  1002  includes a first leg  1002 A and a second leg  1002 B, that are used to grip a picatinny rail, such as rail  9  shown in  FIG. 7 . First leg  1002 A has a mating portion  1030 A and an opening  1035 A, and second leg  1002 B has a mating portion  1030 B and an opening  1035 B. A fastener  1050  is positioned between first leg  1002 A and second leg  1002 B. First end  1056  of fastener  1050  is adapted for receiving the fastener  1050  and is retained in opening  1035 A. Fastener  1050  has a threaded body  1054  that is threadingly received in opening  1035 B, preferably by being threadingly received in a nut  1038  that is retained in opening  1035 B. As fastener  1050  is tightened, it draws together mating portions  1030 A and  1030 B to tighten them against a picatinny rail. Fastener  1050  can then be loosened to remove device  1000  from the picatinny rail. 
     Turning now to  FIGS. 9-13 , the back surface  1040  of device  1000  includes two fasteners,  1078  and  1080 , which as shown are hex head nuts with washers that are received in opening  1090  of circuit board  4000 . 
     Light source  1020  has a first end  1020 A (through which light can be emitted), is preferably a visible-light laser module, but could be any light source, including a light emitting diode (“LED”) flashlight (as used herein “flashlight” means any source of visible light other than a laser) or an infra-red light source (such as an infra-red LED or infra-red laser). In the embodiment shown light source  1020  is a red-light, 650 nanometer or 635 nanometer, 3.3 mm diode, visible laser, and the laser module has an overall length of about 14 mm and a diameter of about 4.5 mm. Any suitable laser/laser module may be used, however. A biasing spring  24  is attached to second end  1020 B to bias light source  1020  towards first end  1020 A when device  1000  is assembled. Light source  1020  preferably includes a diffraction lens (not shown) that converts the single laser beam generated by light source  1020  into multiple, individual beams of light. In embodiments of the present invention, the diffraction lens can be assembled as part of light source  1020  or be positioned outside of light source  1020 . 
     As with device  10 , the multiple light beams generated by device  1000  are spread apart so as to define an area between the light beams. The area can be of any suitable shape for replicating the area in which pellets exiting a shotgun would occupy. It is most preferable that the area defined by the multiple light beams is circular, but it could also be triangular, oval, rectangular, hexagonal, octagonal or of any suitable shape. In one preferred embodiment there are at least three light beams defining the area, and most preferably eight beams of light defining the area, even though any number of light beams of three or more can be utilized. 
     The diffraction lens, or other method of generating multiple light beams, s directs each of the multiple beams of light outward with respect to the longitudinal axis of the light source  1020 . In one embodiment each of the multiple beams is directed outward at 1.7 degrees as measured from the longitudinal axis of the laser  20 . Any suitable outward direction may be used, however, and is based on the size and type of shotgun, so that the pattern of pellet spread for that shotgun is accurately replicated. 
     The light source may also create one or more other light beams inside the area, and preferably creates a single light beam in the center of the area formed by the multiple beams. 
     Power source  1090  can be any suitable power source for light source  1020 , and is preferably an electric power source and most preferably a portable, electrical power source such as a battery or multiple batteries. The embodiment shown uses 3 silver oxide 1.5V silver oxide coin batteries, although any suitable batteries or power source may be used. 
     Device  1000  as shown further includes a housing  2000 , a light source adjustment apparatus  3000 , an integrated circuit board  4000 , a canister  5000  having a first cavity  5002 , a second opening  5004 , a first end  5006 , a second end  5008 , and a dividing wall  5010 . First cavity  5002  retains light source  1020  and light source adjustment apparatus (“LSAA”)  3000 , wherein light source adjustment apparatus  3000  is first positioned over light source  1020  prior to being positioned in first canister  5002 . Second cavity  5004  retains power source  1090 . The ultimate purpose of housing  2000  is to retain light source  1020  and power source  1090  and mount them to a gun, and to selectively connect power source  1090  to light source  1020 . Any suitable structure or structures may be used for this purpose. 
     Housing  2000  is preferably made of injection molded plastic, but could be made of any suitable material, such as another metal (for example, MIM carbon steel or extruded aluminum). Housing  2000  has a first end  2000 A, a second end  2000 B and includes a cavity  2001  that retains canister  5000 . Canister  5000  is preferably made of aluminum or other conductive material so as to complete the connectivity required for the proper functioning of the circuit board  4000 , when circuit board  4000  is pressed against end  5008  of canister  5000  when device  1000  is fully assembled. 
     Housing  2000  has a first end  2000 A with an opening  1020 C to permit light to be emitted from light source  1020  (preferably through a diffraction lens), and an opening  2001 A that retains cap  1004  and permits access to the power source  1090  to permit replacement of the power source. 
     As discussed above, housing  2000  also includes an aperture  1022  that extends to either LSAA  3000  or light source  1020 . A second aperture (not shown) on surface  1081  also extends to either LSAA  3000  or light source  1020 . Each of these apertures are configured to receive a moveable screw (hereafter referred to as “set screw” or “set screws,” which are preferably socket-head set screws), which are not shown for this embodiment. 
     An opening  5004 A in the first end of canister  5004  is preferably threaded (not shown) so that it can receive cap  1004 , which is threaded. A depression  1005  is formed in cap  1004  in order to screw cap  1004  onto end  5004 A. Cap  1004  can be removed to access and replace power source  1090 . 
     A light source adjustment apparatus (or “LSAA”)  3000  is for retaining the light source  1020  when it is positioned in canister  5000  and for assisting in positioning light source  1020 . LSAA  3000  absorbs the recoil of a gun to which device  1000  is mounted thereby enabling light source  1020  to remain in a relatively stable position. As shown in  FIG. 13 , LSAA  3000  may be generally conical and slides over light source  1020 . It is preferably comprised of an elastomeric material, such as neoprene rubber, of about a 60 Shore A to absorb shock, but can be made of any suitable material. As previously described, LSAA  3000  fits into cavity  5002  of canister  5000 . Instead of LSAA  3000 , or in addition to LSAA  3000 , the light source  20  may be biased towards the set screws (not shown in this embodiment) by springs (not shown). 
     When device  1000  is assembled, the position of light source  1020  can be adjusted utilizing the set screws (not shown). LSAA  3000  and/or the springs (not shown) can bias the light source  1020  towards the set screws. As one or both of the set screws are tightened, the set screw(s) pushes against the LSAA  3000  or the light source  1020  and moves the light source  1020  either sideways and/or vertically thereby adjusting the position of light source  1020 . 
     Integrated circuit board  4000  is configured to be received and mounted on plate  1070  of housing  2000 . The basic purpose of board  4000  is to connect the power source  1090  to the light source  1020  and any suitable structure or device can be used for this purpose. Board  4000  is preferably plastic and interacts with two push button switches  1072  and  1074 . Board  4000  includes an integrated circuit (not shown) and two through screw holes  1090 . Current is transferred via board  4000  to laser module  1020 . Board  4000  is designed for negative switching wherein power is generated from the negative side of power source  1090  (which are batteries in this embodiment) and through spring  1024  of light source  1020  in this embodiment. In the preferred embodiment of device  1000 , the integrated circuit allows for continuous delivery of power to light source  1020 . 
     In this embodiment, spring  1024  is connected to the back of laser module  1020  in any suitable manner, and is then connected to board  4000 , preferably by soldering. Spring  1024  acts as the negative contact for module  1020  to board  4000  and also allows module  1020  to move freely back and forth axially and in all directions. In this manner, module  1020  can freely be adjusted by the previously described set screws. 
     Buttons  1072  and  1074  are preferably identical and of any suitable shape to fit in the openings in plate  1070  and switch power off or on to light source  1020 . Each button  1072  and  1074  operates independently and is for enabling a user to selectively activate a switch to turn the light source  1020  off or on, and any suitable device or structure can be used for this purpose. 
     Device  1000  also preferably includes a backing, such as backing  5000 , which is preferably plastic. Although not shown here, the backing is of a suitable size, shape and material to function the same as previously described backing  500 . 
     A sighting device according to the invention may be mounted to a shotgun in any suitable manner utilizing any suitable structure. 
     Having thus described some embodiments of the invention, other variations and embodiments that do not depart from the spirit of the invention will become apparent to those skilled in the art. The scope of the present invention is thus not limited to any particular embodiment, but is instead set forth in the appended claims and the legal equivalents thereof. Unless expressly stated in the written description or claims, the steps of any method recited in the claims may be performed in any order capable of yielding the desired result.

Technology Classification (CPC): 5