Abstract:
An apparatus providing a regenerative light source capable of illuminating a large area in front of and around the barrel end of a firearm. The apparatus may be installed as a retrofit into the firearm body without any need to alter it. Moreover, the light source and the electronics powering are will be shielded from environmental hazardous associated with the operation of a firearm thus prolonging the life of the apparatus while ensuring it remains functional whenever needed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     None. 
     NOTICE OF COPYRIGHT AND TRADE DRESS 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. This patent document may show and/or describe matter which is or may become trade dress of the owner. The copyright and trade dress owner has no objection to the facsimile reproduction by any one of the patent disclosure as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright and trade dress rights whatsoever. 
     TECHNICAL FIELD 
     The present invention relates generally to a retrofit assembly for use with a firearm and, more particularly, to an illumination apparatus that may be installed within a firearm to assist with aiming and shooting a firearm in varying ambient light conditions. 
     DISCUSSION OF THE RELATED ART 
     Light beams have long been used as sight aids for weapons. When ambient light conditions may vary from low light to complete darkness, an improved aiming device that allows quicker and more accurate aiming of a weapon becomes an advantage. Particularly with law enforcement, armed forces and security personnel for whom, under life threatening situations, a fraction of a second can mean the difference between life or death. 
     It is known in the art to provide a light source within a hand gun such as a semiautomatic pistol. For example, laser sights for weapons are well known in the art. The prior art teaches that lasers be used as a means of generating light beams for sighting applications. Lasers have come to be known for their high intensity, small spot size, and how they can be focused into a narrow beam with minute divergence angles. Although they provide a distinct advantage, they are ineffective when it becomes desirous to illuminate a large space to asses potential threats contained therein. 
     In the past, one way this problem had been addressed was by holding a lighted flashlight with the hand not holding the firearm or, in some instances, mounting the flashlight to the outside of the firearm. In a critical situation, the execution of this method can expose individuals to unnecessary risk. Having to reach for and separately operate a flashlight results in lost time and an impaired response. This is a problem that becomes compounded even further when the person operating the weapon finds themselves in a situation whereby lost time can expose them to life threatening danger. 
     Various devices have been suggested in an attempt to provide solutions to the aforementioned problems. However, some of these proposals are not desirable because they are bulky, heavy and require advanced and/or expensive adaptations to be made to a firearm in order to retrofit the device. Luminous sights have been proposed that use light emitting diodes (LED) as a means of illumination. These proposed luminous sights comprise bare LED lamps without any means of modification of the quality of light which is radiated away from and viewed by the user. The excessive amount of glare produced by these types of light sources make them extremely difficult to view and can be distracting and/or irritating. 
     One example of an illuminated site comprising LED lamps is in U.S. Pat. No. 3,833,799. The &#39;799 patent discloses an illuminated gun sight system which uses an LED lamp as an isolated frontal sight element in a supplemental installation on a conventional front gun sight of a firearm. This illuminated frontal sight is intended to be viewed by the user as a pinpoint of light through a rear conventional iron sight and is therefore not a solution for firearms lacking this feature. 
     Patent application Ser. No. 10/846,271 teaches an LED adapted to protrude from the front of the firearm. A gun with such a light source cannot generally be carded in a conventional holster. This is a substantial drawback caused by the fact the LED may be easily damaged or knocked out of alignment with the barrel of the firearm. Moreover, positioning the light source in such a hazardous environment as the outside of the firearm exposes it to spray back, led dust, burnt powder, carbon deposits, and other substances that significantly reduce the functionality and lifespan of the light source. Moreover, this application provides no means for adjusting the alignment of the light beam relative to the weapon boresight. 
     Furthermore, the use of a bare LED lamp on a gun sight, without modification of the light emitted therefrom, presents a problem of inaccuracy. This is because the physical center of the LED lamp does not coincide exactly with the physical location of the illuminating crystal embedded within the lamp. The pinpoint of light inside the LED lamp is of uncertain location due to structural inconsistencies inherent in the manner in which these devices are manufactured. This is an inherent characteristics of LED lamps which presents a problem of inconsistency and inaccuracy. 
     Accordingly there exists a need for a bright light source which may be installed as a retrofit on a firearm that comprises a means for protecting the light source from environmental hazardous tangential to use in close proximity with the barrel of a firearm. It would be further desirous for such a retrofit to allow the user to make adjustments to the light beam. An additional need is for such a retrofit to be comprised of lightweight materials and comprise state of the art light and battery technology without adding any bulk of the weapon. The present invention effectuates these needs. 
     SUMMARY 
     An apparatus is herein disclosed for providing a regenerative light source capable of illuminating a large area in front of and around the barrel end of a firearm. The apparatus may be installed as a retrofit into the firearm body without any need to alter it. The light source and the electronics powering it will be shielded from environmental hazardous associated with the operation of a firearm such as spray back, led dust, burnt powder, and carbon deposits thus prolonging the life of the apparatus while ensuring it remains functional whenever needed. 
     The apparatus of the present invention is comprised of a hollow chamber with a front end which is fixed on the distal end zone of the firearm&#39;s barrel and a rear end which is fixed on the proximal end zone of the firearm&#39;s barrel. The chamber is comprised on an electrically conductive material by way of example, an not limitation, stainless steal. An illumination means is located within the chamber and is operative to radiate highly luminous light substantially parallel in relation to the central longitudinal axis of the barrel. A means for reflecting or refracting light is further provided to adjust, among other things, the reference shape of uniform light intensity throughout the visible light radiating area of the illumination source. 
     The apparatus further comprises a means for providing electric current to the illumination source housed within the hollow chamber. In one embodiment, the current providing means may be a series of button-type silver oxide (SR) batteries. SR batteries have been found to have superior characteristics making them well suited for use within a firearm and powering a highly luminous light source. These batteries exhibit a flat discharge curve during which they supply a stable voltage until the end of the discharge life. A flat discharge curve during discharge means a more stable voltage until the end of the discharge life ensuring consistency in the amount and type of illumination. Excellent discharge load characteristics and leakage resistance make them a superior alternative to commonly used alkaline varieties. 
     The manual on/off switch of the present disclosure is a retrofit piece shaped to mimic the take down lever of the firearm while being capable of completing the circuit which provides current to the illumination source. The apparatus further comprises an end cap for engaging the rear of the chamber having a metal electrical contact. The metal electrical contact engages the retrofit take down lever which is movable horizontally to selectively contact the metal contact for making selective electrical contact therewith. The circuit may be completed by sliding the take down lever either to the left or to the right. When the lever is in the center, a small piece of insulating material, disposed in the center of the lever, engages the electrical contact thus shutting off the light source. 
     A further feature of the apparatus described herein is a highly luminous light source with substantially greater power and intensity than any light source heretofore disclosed in the art of the present disclosure. By using a light source powered by the aforementioned current providing means, the light source of the present apparatus can emit 40,000 mcd of high intensity light. This amounts to approximately four times the luminosity of any previously disclosed light source. This substantial increase pays dividends in the perilous situations commonly faced by law enforcement officials where it is essential quickly and accurately identify potential threats. 
     Furthermore, the substantial increase in light intensity means the light source no longer needs to be fitted to the outside of the firearm in order to be effective. Accordingly, the light source of the present disclosure is secured to the inside of the hollow chamber nestled within the firearm where it is safe from environmental hazards which would otherwise damage the light source. Situating the light source in such a manner means additional space is made available at the front of the chamber for receiving a means of reflecting and refracting the emitted light. In one embodiment, this may be a lens that also provides an additional layer of protection by further isolating the light source from the environmental hazards outside of the firearm. 
     In one embodiment, the light source will be secured within the chamber using an optical adhesive. An optical adhesive comprises a lower refractive index than conventional adhesives to ensure nominal impact on the luminosity and clarity of the light source. Furthermore, optical adhesives have low viscosity, fast curability, and excellent heat resistance properties all of which make it ideally suited for use within a firearm. 
     An object of the apparatus is to provide an assembly for use on a firearm and, specifically, a regenerative high luminous efficiency light source isolated from the hazardous which may denigrate the light source reducing its life span and efficacy. 
     A further object of the present disclosure is to provide a retrofit illumination apparatus to facilitate accurate aiming of a firearm in all ambient light conditions by emitting high luminous efficiency light from the distal end of a firearm. 
     It is still a further object of the present invention to provide an assembly for use on a firearm including luminous elements on the front wherein the entire assembly may be retrofit into the firearm and does not substantially alter the size, shape, or weight of the firearm. Numerous other features, objects and advantages of the invention will become apparent from the following description when read in conjunction with the accompanying drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Figures 
         FIG. 1  is an installed perspective view of an exemplary embodiment of the retrofit illumination apparatus of the present invention; 
         FIG. 2  is a front perspective view of the apparatus of  FIG. 1 ; 
         FIG. 3  illustrates the firearm and apparatus of  FIG. 1  once the slide has been detached from the firearm body; 
         FIG. 4  is an exploded view of the retrofit illumination apparatus; 
         FIG. 5  is an exploded view illustrating one embodiment of the apparatus; and 
         FIG. 6  is an exploded view illustrating a second embodiment of the apparatus. 
     
    
    
     For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements. 
     The terms “first,” “second,” “third,” “fourth.” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms “include,” and “have,” and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, device, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus. 
     The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,” “under,” and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. 
     The terms “couple,” “coupled,” “couples,” “coupling,” and the like should be broadly understood and refer to connecting two or more elements or signals, electrically, mechanically or otherwise. Two or more electrical elements may be electrically coupled, but not mechanically or otherwise coupled; two or more mechanical elements may be mechanically coupled, but not electrically or otherwise coupled; two or more electrical elements may be mechanically coupled, but not electrically or otherwise coupled. Coupling (whether mechanical, electrical, or otherwise) may be for any length of time, e.g., permanent or semi-permanent or only for an instant. 
     DETAILED DESCRIPTION 
     Illustrative embodiments of the invention are described below. The showings are for purposes of illustrating preferred embodiments and not for purposes of limiting the same. The following explanation provides specific details for a thorough understanding of an enabling description for these embodiments. One skilled in the art will understand that the invention may be practiced without such details. 
       FIG. 1  is an installed perspective view of an exemplary embodiment of a retrofit illumination apparatus  10  for a firearm  100  in accordance with one embodiment of the present invention. The apparatus  10  comprises a forward or head end  12  out of which light is directed by a light source (not shown in this figure). By way of example, and not limitation, such a light source may be a light emitting diode (LED) which, in one embodiment, may be covered by a lens  13  positioned on the head end  12  of the apparatus  10 . The lens  13  is further provided as a means of adjusting a light beam emitted from the light source. The lens  13  is also operative as a means for shielding the apparatus  10  and the contents of the housing, illustrated in  FIGS. 5-6 , from environmental hazards associated with firearm use. Such hazards may include spray back, led dust, burnt powder, carbon deposits, and other substances. 
       FIG. 2  is a front perspective view illustrating the location of the lens  13  with respect to the barrel  15  of the firearm  100 . This figure further emphasizes how the light source does not protrude from the front end  12  of the firearm  100 . Positioning the light source within the firearm  100  is operative to isolate the light source from environmental hazards which would otherwise damage it. The harsh environments and extreme conditions to which firearms are typically exposed, mean positioning a light source close to the barrel  15  will inevitably impact the quality of light being emitted as well as the lifespan of the light source. 
       FIG. 3  illustrates the firearm  100  once the slide  102  has been detached from the firearm body  104 . The slide  102  is shown laying flat on a surface with the underside facing up while the body  104  is shown in profile view. The firearm  100  comprises a recoil spring  106  which is located within a designated compartment  108  beneath the barrel. 
       FIG. 4  is an exploded view of the retrofit illumination apparatus  10  of  FIG. 3  illustrating the external and internal components thereof and where the apparatus  10  is removed from within the firearm  100 . In this example, the apparatus is placed within the confines of the recoil spring  106 . However, this is introduced by way of example and not limitation. One of ordinary skill in the art will recognize that the apparatus  10  of the present invention may be modified to act as a retrofit for any number of different firearms comprising a compartment  108  to house the apparatus  10  and an opening  12  (see  FIG. 1 ) through which light may be emitted. 
       FIG. 5  is an exploded view illustrating one embodiment of the apparatus  10  and the contents of the apparatus housing  20 . The housing  20  comprise a front  16  and rear  18 , an elongated hollow cylindrical portion  22 , and a hollow reduced inner diameter portion  24  proximate to the front end  16  of the housing  20 . A circular tail cap  30  overlies the cylindrical housing  20  at the rear  18  of the apparatus  10 . The cylindrical housing  20  comprises a plurality of external threads at the rearward end  18  for engaging the internal threads on the inner surface of tail cap  30 . A pin  32  protruding from the cap  30  engages a metal switch member  40  that, when installed, protrudes from the sides of the firearm  100  and comprises at least three positions: right, left, and center. The light source  14  may be turned on by either sliding the switch member  40  to the right or to the left. The light source  14  may be turned off by sliding the switch member  40  to the middle position. 
     The tail cap member  30  is shown removed whereas it would be positioned at the rearward end  18  of the apparatus  10  when installed. The tail cap  30  comprises a generally cylindrical pushbutton  32 . The pushbutton  32  further comprises a rearward cylindrical section that projects through a hole in the tail cap  30 . In one embodiment, the tail cap  30  is comprised of an insulating plastic and has a circumferential groove to provide a seal between the tail cap  30  and the rear end of the housing  18 . The tail cap  30  further comprises a cylindrical skirt  36  extending forwardly from the internal threads and along the housing  20 . This also provides greater length thereby facilitating easier grip for rotating tail cap  30  relative to the housing  20 . 
     The apparatus housing  20  comprises a variety of different members fitted together to form the retrofit light emitting apparatus  10  of the present invention. These members further comprise: at least one light source assembly  14  and at least one power source. In one embodiment, the power source may comprise a plurality of batteries  50  each having a negative terminal  52  and a positive terminal  54 . By way of example, and not limitation, there may be four batteries connected in series to provide a source of electricity for energizing the light source  14  thus causing it to emit light. 
     The apparatus is powered by an electricity source which may be positioned in the rearward cavity  22  of the chamber  20 . By way of example and not limitation, four batteries  50  may be employed, although a greater or lesser number may be utilized by appropriately extending or shortening the length of the cavity  22 . Preferably, batteries are of the of a silver-oxide type. In one embodiment the battery size is 393 and interchangeable with sizes SR48, 193/309/393, SR754, 1136SO, 1137SO which have a typical capacity of 70 mAh milliampere-hour and a diameter of less than 0.8 inch. As a result, the apparatus  10  may have an outer diameter of less than 1 inch. All of the batteries may be shrink wrapped together to facilitate installation and removal from the rearward cavity  22  as well as protect against shorting which may occur should the batteries  50  come into contact with the inside of the hollow chamber  20 . Furthermore, in use, these batteries have shown regenerate properties which prolong the their useful life and increase the amount of time in between installation and having to be replaced. 
     Selective electrical connection between negative terminal  52  of rearward batteries  50  and the rearward end of the tail cap  30  is made via a circular metal plate which is electrically connected to the switch member  40  by the outwardly extending circular metal pin  32 . When the switch member  40  is moved to the right or left position relative to the firearm  100  the metal switch member  40  comes into electrical contact with the pin  32  thereby completing an electrical circuit comprising the batteries  50  and light source  14 , to the end of applying electrical potential to the light source  14  causing it to emit light. 
     In one embodiment, the apparatus  10  comprises solid state light source  14 , preferably a light-emitting diode (LED). LEDs are available to emit light of one of a variety of colors, e.g., white, red, blue, amber, or green, and have extremely long expected lifetimes, e.g., 100,000 hours. The light source  14  mounts into front portion  24  of the housing  20  with one electrical lead thereof to making electrical contact with the interior surface of the cylindrical housing  20 . The other electrical lead projects rearwardly out of the front compartment  24  of the cylindrical housing  20  to come into electrical contact with the positive terminal  54  of forward battery  56 , thereby completing an electrical circuit between the power source and housing  20  through light source  14 . 
     In the example illustrated in  FIG. 5 , current flows from the positive terminal of the power source through a contact, such as the circular metal plate, in the tail cap  30  and the circuit is either opened or closed by the moving the switch  40  to a particular position. The current travels to the barrel  15  via a lug that catches on the switch  40 . Next, it travels into the slide  102  and recoil spring  106 , and to the housing  20 . As illustrated in  FIG. 5 , the LED anode is electrically coupled to the housing  20  through the LED cathode and through a regulating circuit board  60  to the first negative terminal in the series of batteries  50 . 
     In the embodiment of the apparatus  10  illustrated in  FIG. 6 , current flows from the positive terminal of the power source through the contact in the tail cap  30  and the circuit is either opened or closed by the switch  40 . The current travels to the barrel  15  via a lug that catches on the switch  40 . Next, it travels into the slide  102  and recoil spring  106  and to the housing  20 . The embodiment provided by way in  FIG. 6  does not comprise a circuit board. Thus, the LED anode is electrically coupled to the housing  20  through the LED cathode directly to the first negative terminal in the series of batteries  50 . 
     Switch member  40  is free to move axially within respect to the housing  20  and tail cap  30 , and does so under pressure applied to member  40 . Moving the switch member  40  to the middle position brings the metal pin  32  in contact with a nonconductive material  42  selectively positioned in the center of the of the switch member  40  thereby breaking the electrical circuit comprising the batteries  50  and light source  14 . This de-energizes the light source  14  and stops the emission of light from the front end of the firearm  100 . 
     Further operative for protecting the light source  14  from environmental hazards related to operating a firearm  100  is the position of the light source  14  within the housing. To further isolate the light source from unnecessary exposure that may effect the functionality of the apparatus  10 , it is envisioned that, in one embodiment of the present disclosure, the light emitting end of the light source  14  is positioned within the housing  20  and not protruding from it. By way of example, and not limitation, the light source may be installed so as to be at least 0.25 inches from the front end  12  of the housing  20 . 
     Moreover, in one embodiment of the apparatus  10 , light from the light source  14  passes through a lens  13  and is emitted from the front face  12  of the apparatus  10 . In another embodiment, the lens  13  may act to modify the light emanating from the light source  14  so that the light emitted from the front of the apparatus  10  is of a uniform intensity throughout a visible light radiating area. Furthermore, in order to improve the luminous reference shape, mask and/or hood means may be provided on the front face of the housing  20 . 
     Although the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes may be made without departing from the scope of the invention. Accordingly, the disclosure of embodiments is intended to be illustrative of the scope of the invention and is not intended to be limiting. It is intended that the scope of the invention shall be limited only to the extent required by the appended claims. To one of ordinary skill in the art, it will be readily apparent that the devices and method discussed herein may be implemented in a variety of embodiments, and that the foregoing discussion of certain of these embodiments does not necessarily represent a complete description of all possible embodiments. Rather, the detailed description of the drawings, and the drawings themselves, disclose at least one preferred embodiment, and may disclose alternative embodiments. 
     All elements claimed in any particular claim are essential to the embodiment claimed in that particular claim. Consequently, replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described with regard to specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims, unless such benefits, advantages, solutions, or elements are stated in such claim. 
     Moreover, embodiments and limitations disclosed herein are not dedicated to the public under the doctrine of dedication if the embodiments and/or limitations: (1) are not expressly claimed in the claims; and (2) are or are potentially equivalents of express elements and/or limitations in the claims under the doctrine of equivalents 
     CONCLUSIONS, RAMIFICATIONS, AND SCOPE 
     While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. For example, the apparatus is illustrated as being installed in one particular firearm in some embodiments even though the inventors contemplate the possibility that it may installed in a variety of different firearms all the while comprising the properties of the invention. Accordingly, is not intended that the invention be limited, except as by the appended claims. 
     The teachings provided herein can be applied to other systems, not necessarily the apparatus described herein. The elements and acts of the various embodiments described above can be combined to provide further embodiments. All of the above patents and applications and other references, including any that may be listed in accompanying filing papers, are incorporated herein by reference. Aspects of the invention can be modified, if necessary, to employ the systems, functions, and concepts of the various references described above to provide yet further embodiments of the invention. 
     Particular terminology used when describing certain features or aspects of the invention should not be taken to imply that the terminology is being refined herein to be restricted to any specific characteristics, features, or aspects of the retrofit firearm illumination apparatus with which that terminology is associated. In general, the terms used in the following claims should not be constructed to limit the apparatus to the specific embodiments disclosed in the specification, unless the above description section explicitly define such terms. Accordingly, the actual scope encompasses not only the disclosed embodiments, but also all equivalent ways of practicing or implementing the disclosed apparatus. The above description of embodiments of the apparatus is not intended to be exhaustive or limited to the precise form disclosed above or to a particular field of usage. While specific embodiments of, and examples for, the retrofit firearm illumination apparatus are described above for illustrative purposes, various equivalent modifications are possible which those skilled in the relevant art will recognize. 
     While certain aspects of the retrofit firearm illumination apparatus are presented below in particular claim forms, the inventor contemplates the various aspects of the apparatus in any number of claim forms. Accordingly, the inventor reserves the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the retrofit firearm illumination apparatus.