Abstract:
An attachment for a firearm with a removable barrel screws onto the firearm in place of the barrel and enables firing a flare. The attachment includes a firing pin housing with a sliding firing pin extension, and a flare cartridge barrel, which may be temporarily removed to receive a flare cartridge and then replaced. The normal bolt action of the firearm actuates the firing pin extension to fire the flare cartridge.

Description:
BACKGROUND OF THE INVENTION 
     This invention generally relates to flare guns, and more particularly to an improved flare attachment designed to be used with a firearm with a removable barrel. 
     Flare guns are known to be used exclusively for signaling purposes by firing a cartridge similar to a 12-gauge shotgun cartridge to obtain a light signal or illumination for military or emergency purposes. Since the mechanism for firing a projectile and the mechanism for firing a flare cartridge is similar, firearms have been proposed which are adaptable to serve a dual purpose, so as to be used either as an offensive weapon or as a signaling device. 
     A firearm is disclosed in U.S. Pat. No. 4,648,192—Harness, in which a short barrel capable of firing flares is exchanged for another barrel capable of firing projectiles. Another proposal is disclosed in U.S. Pat. No. 5,148,620—Nelson, in which a shotgun shell adapter fits into the breech of a shotgun, enabling the gun to accept various sizes of cartridges. A particular difficulty results from providing a gun, which is capable of firing both center fire and rim fire cartridges. U.S. Pat. Nos 4,644,930—Mainhardt, discloses a gun capable of firing a variety of projectiles, both center fire and rim fire by employing various inserts. 
     All of the foregoing constructions employ complex mechanisms. It would be desirable to provide a simple and lightweight flare attachment designed to fit a firearm with a removable barrel, to be used in place of the projectile barrel for firing conventional signal flares. It would also be desirable to provide a flare attachment for a firearm with removable barrel, which can be attached in lieu of the barrel and provide further for rapid removal of spent flare cartridges and insertion of new flare cartridges. 
     Accordingly, one object of the present invention is to provide an improved flare attachment for a firearm with removable barrel. 
     Another object of the invention is to provide a simple and inexpensive flare attachment, which can be made primarily of plastic construction. 
     Still another object of the invention is to provide an improved and simple flare attachment with means to rapidly load and reload conventional flare cartridges. 
     SUMMARY OF THE INVENTION 
     Briefly stated, the invention comprises of a flare attachment for a firearm with a removable barrel, said firearm being of the type having a receiver with a bolt, cocking lever and recoil springs for actuating the firing pin, the receiver having an attachment end for receiving said removable barrel. The flare attachment comprises a firing pin housing having a central bore and including first attachment means arranged to attach the firing pin housing to the attachment end of said receiver, a flare cartridge barrel having a flare chamber shaped to receive a flare cartridge therein, and including second attachment means arranged for temporarily attaching the flare cartridge barrel to the firing pin housing so that the central bore is coaxial with the flare chamber. A firing pin extension as slidably disposed in the central bore having a first end for receiving impact from said bolt when the firing pin extension is in a first position and a second end for impacting a flare cartridge in said flare chamber when the firing pin extension slides to a second position. A retainer restricts the axial movement of the firing pin extension in the central bore, and a spring biases the firing pin extension away from the flare cartridge barrel to said first position, whereby the first end may receive an impact from said bolt. 
     In the preferred embodiment of the invention, the flare cartridge barrel and firing pin housing are manufactured of plastic and threaded together, having a lanyard connecting the two elements. 
    
    
     DRAWINGS 
     Other objects and advantages of the invention will be better understood by reference to the following drawings, taken in connection with the accompanying description, in which: 
     FIG. 1 is a side elevation view of a firearm with a removable barrel, shown removed, and illustrating also the flare attachment, 
     FIG. 2 is a side elevational view in cross section of the flare attachment, 
     FIG. 3 is a side elevational view of a modification of the flare attachment, and 
     FIG. 4 is a rear-end view of the flare attachment shown in FIG.  2 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1 of the drawing, a firearm, shown generally as  10  is especially adapted to receive a removable barrel shown generally as  12  or, in lieu thereof, a flare attachment according to the present invention, shown generally as  14 . A suitable firearm  10 , together with a removable barrel  12  is commercially available under the trade name AR-7 from AR-7 Industries, LLC, Meriden, Conn. A similar firearm with removable barrel is available from Henry Repeating Arms, located in Brooklyn, N.Y. The distinctive feature of the AR-7 is that a receiver, barrel and magazine may all be disassembled stowed inside a hollow stock. This particular feature of the AR-7 is not relevant to the present invention, which can be used with any type of firearm having a removable barrel. 
     Referring to FIG. 1 of the drawing, firearm  10  includes a stock  16 , a receiver  18 , and cartridge magazine  20 . Disposed inside receiver  18  is a bolt and recoil spring mechanism (not shown) actuatable by a cocking lever. The mechanism will vary according to the type of firearm. Construction of the bolt and recoil spring mechanism is not relevant to the present invention but well-known to those skilled in the art. Actuation of the cocking lever causes the bolt to travel along the central axis of a bore in the receiver  18  to impact the end of the cartridge in barrel  12 . A firing pin may be designed to impact either a rim-fired cartridge or a central fired cartridge. 
     Receiver  18  includes a threaded end  24 . Barrel  12  includes a barrel nut  26  with internal threads matching those of the threaded end  24 . By unscrewing barrel nut  26 , the barrel  12  may be easily and quickly removed from receiver  18 . 
     Improved flare attachment  14  which is the object of the present invention is provided with a barrel nut  28  identical to the barrel nut  26  on the barrel, enabling the flare attachment  14  to be quickly and easily attached to or removed from threaded end  24  on receiver  18 . 
     Referring now to FIGS. 2 and 4 of the drawing, the preferred version improved flare attachment  14  is shown in enlarged views. Details of flare attachment  14  are best seen in the cross-sectional drawing of FIG.  2 . Flare attachment  14  includes two major separable parts, namely a firing pin housing  30  and a flare cartridge barrel  32 . The firing pin housing is a longitudinal cylindrical member, preferably manufactured of high-impact plastic, defining a central bore  34  along its axis. The internally threaded barrel nut  28  is retained by flange  36  on the firing pin housing. An internal thread  38  matches the external threaded end  24  on the receiver of the firearm. A receiver locator pin  40  matches a slot (not shown) in the receiver  18  to prevent rotation of the housing  30  when the barrel nut  28  is tightened and held with a barrel nut lock washer  42 . 
     Flare cartridge barrel  32  is also a cylindrical, longitudinal member with an internal bore  44  coaxial with central bore  34 . A portion of bore  44  is shaped to provide a flare chamber  46  shaped to receive a conventional flare cartridge. Flare cartridge  48  is shown in dotted lines and is generally the shape of a short, 12-gauge shotgun shell. 
     The flare cartridge barrel  32  is also preferably made of the same plastic material as the firing pin housing  30  and the two are attached together by means of a threaded connection  50 . The threaded connection  50  may alternately comprise an interrupted bayonet thread for rapid assembly and disassembly. 
     In order to prevent losing or dropping the flare cartridge barrel when it is removed for inserting a new cartridge  48 , members  30  and  32  are connected by a lanyard  52 , the ends of which are attached to rings  54 ,  56  disposed in angular grooves in the respective members  30 ,  32 . 
     In order to fire the flare cartridge, a firing pin extension  58  is slidably disposed in the central bore  34 . The firing pin extension  58  has a first end  60  for receiving impact from the bolt of the firearm when the firing pin is in a first position extending to the left, and a second end  62  for impacting the flare cartridge  48  in the flare chamber when the firing pin extension slides to a second position to the right. The firing pin extension  58  is shown in a second position in the FIG. 2 drawing. A firing pin retainer  64  in the end of the firing pin housing restricts the movement of the firing pin extension to the left in bore  34 . A spring  66  biases the firing pin extension  58  toward the left side, or first position. 
     Modification 
     A modified form of the invention is shown in FIG. 3 as a flare attachment  68 . Rather than a threaded connection  50 , firing pin housing  70  and a flare cartridge barrel  72  are connected using a cam slot and radial pin arrangement. One or more radial pins  74  are arranged to project from a smooth cylindrical surface of firing pin housing  70  and one or more cam slots  76  are cut in the cylindrical wall of flare cartridge barrel  72 . Other than this, there are no differences from flare attachment  14 , shown in the cross-section of FIG.  2 . 
     Operation 
     The invention operation follows: 
     Flare attachment  14  is screwed to the receiver  18  using the barrel nut  28 . In order to insert a flare cartridge, the flare cartridge barrel  32  is unscrewed from the firing pin housing  30 , rotation of the two members relative to one another being permitted by rotation of the rings  54 ,  56  on the respective members. A flare cartridge  48  is inserted into flare chamber  46  and the flare cartridge barrel  32  screwed back on to the firing pin housing  30 . Actuation of the cocking lever causes the bolt in the firearm receiver  18  to impact the first end  60  of firing pin extension  58 , where it is held biased to the left by spring  66 . The impact causes firing pin extension  58  to travel to the right and the second end  62  to impact the primer of flare cartridge  48 , firing the flare from bore  44 . Removal of the spent cartridge and insertion of a new cartridge proceeds in the same manner. 
     Equivalent constructions to the threaded connection  50  are well-known in the art. As mentioned previously, the threaded connection may be an interrupted bayonet type thread. Alternatively, one or more cam slots may be provided in the flare cartridge barrel  32  which mate with pins mounted radially in the firing pin housing  30 , as shown in FIG.  3 . 
     By constructing the flare attachment  14  of plastic material, a less expensive construction is obtained, since the larger components of the flare attachment can be made by injection molding to reduce the cost. 
     While a barrel nut is shown as a means of attachment to the firearm, any type of attachment may be employed which corresponds to the attachment used on the removal barrel of the selected firearm. 
     While there has been described what is considered to be the preferred embodiment of the invention, other modifications will occur to those skilled in the art, and it is desired to secure in the appended claims all such modifications as fall within the true spirit and scope of the invention.