Patent Publication Number: US-6901691-B1

Title: Minimum exposure weapon

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to firearms and, more particularly, pertains to a minimum exposure weapon which allows the user to stabilize and fire the weapon from a covered position with minimal exposure to enemy fire. 
   2. Description of Prior Art 
   The use of firearms is known in the prior art. More specifically, firearms heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements. 
   Known prior art includes U.S. Pat. Nos. Des. 324,557; 6,637,141 B1; 6,598,329 B1; 6,517,133 B2; 6,397,507 B1; 6,070,355; 5,675,112; 4,878,305; 4,827,652; 4,677,781; 3,369,316; 2,826,848; 2,771,697; and 1,386,247. 
   The inventive device substantially departs from the conventional concepts and designs of the prior art and in doing so provides a weapon primarily developed for the purpose of allowing a user to support the weapon in the conventional stance (utilizing both hands and a shoulder to brace the weapon) while having a minimal exposure to enemy fire. 
   In view of the foregoing disadvantages inherent in the known types of firearms now present in the prior art, the present invention provides for increased weapon stability while allowing the user to fire from behind structures with a minimum of exposure to incoming fire. 
   SUMMARY OF THE INVENTION 
   The minimum exposure weapon consists of a pre-existing weapon upon which is retrofitted by replacing the rear stock and buffer tube with the improved stock and buffer tube. The improved stock is a collapsible stock and has the ability to pivot to the left or to the right. A front stabilizer is mounted to the forward hand guard and its purpose is to pivot out and make contact with the corner of a wall while allowing the barrel to protrude adjacent to the wall. 
   For example, to shoot from behind the left corner of a wall, the rear stock would be pivoted left and locked into position and the front stabilizer would be pivoted left and locked into position. A horizontal compact periscope would then be mounted from the left into a mount on the upper receiver and locked into position. 
   At this point, the shooter would use a conventional standing stance, gripping the rifle with his left hand on the forward handgrip, right hand on the trigger pistol grip, and pivoted stock butt against right shoulder. The shooter can lean his upper body weight against the stock and the weapon is effectively pinned between his shoulder and the wall. The weapon is supported and steadied. Mounted on the distal end of the front stabilizer is a shock absorber gripper, and as the weapon is fired the weapon recoils through the stock and into the shooter&#39;s right shoulder, but because the shooter is leaning into the stock, the amount of travel of the weapon is greatly reduced. The shock absorber gripper helps to prevent any hammering or excessive forces being applied to the weapon or to the shooter&#39;s right shoulder after the primary recoil. In other words, the shock absorber gripper cushions the contact between the gun and the wall, and also applies a friction point between the gun and the wall to stabilize and hold the weapon. 
   The horizontal compact periscope is used to allow the shooter to visually align the upper receiver mounted sight with the far sight mounted on the barrel during target acquisition while the shooter is hidden behind the wall. 
   The rear stock assembly is unique because it is not mounted to the buffer tube, but is mounted to a stock adaptor, which in turn is mounted to the lower receiver of the weapon. The stock assembly contains a stock extension, a rectangular bar, in which the stock interfaces. The stock extension contains a number of detents on which the slider pin can lock in; this gives the stock its collapsible function. The stock adaptor also contains a locking pin which, when released, allows the stock extension to rotate about the pivot pin which attaches it to the stock adaptor. The same locking pin will interface with the detent holes in the stock extension which locks the pivot position of the stock assembly to either neutral, left or to the right. 
   The front stabilizer is mounted to the bottom picatinny style rail on the forward hand guard utilizing the front stabilizer mount. The mount contains a locking pin which will lock the front stabilizer in the neutral position or will, when unlocked, allow it to rotate to the left or to the right. 
   The horizontal compact periscope has picatinny styled accessory mounts which allow it to be mounted bilaterally (left or right) into the upper receiver transverse sighting mount. The transverse sighting mount contains a locking pin to lock the horizontal compact periscope in position. 
   It is an object of the present invention to provide a weapon which can be carried and used as a conventional weapon and when necessary this weapon can be rapidly converted real time to support firing from behind a comer of a building or object. 
   It is a further object of the invention to provide a sighting system which is strictly passive in nature (requiring no electronics or power sources, i.e., rechargeable batteries) in order to assure the reliability of a system which may be exposed to various environments and extreme variation of combat conditions over prolonged periods of time that the user may be in the field. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a left side elevated view of a typical tactical weapon embodying the present invention with the weapon in the conventional mode. 
       FIG. 2  is a left side elevated view of the weapon in the minimum exposure weapon mode. 
       FIG. 3A  is a left side view of the rear stock. 
       FIG. 3B  is a detailed view of the slider locking pin assembly. 
       FIG. 4  is an anterior to posterior end view of the rear stock. 
       FIG. 5  is the bottom view of the stock extension. 
       FIG. 6  is a left side view of the stock extension. 
       FIG. 7  is a top view of the stock extension. 
       FIG. 8  is a left side view of the stock adaptor. 
       FIG. 9  is a posterior to anterior view of the stock adaptor. 
       FIG. 10  is an anterior to posterior view of the stock adaptor (the lower receiver mating surface). 
       FIG. 11  is a left side view of the front stabilizer mount. 
       FIG. 12  is an anterior to posterior view of the front stabilizer mount. 
       FIG. 13  is a bottom view of the front stabilizer mount. 
       FIG. 14  is a left side view of the front stabilizer assembly. 
       FIG. 15  is the top view of the front stabilizer assembly. 
       FIG. 16  is the bottom view of the front stabilizer assembly. 
       FIG. 17A  is the left side view of the buffer tube. 
       FIG. 17B  is an end view of the buffer tube. 
       FIG. 18  is a left side view of the transverse sight mount. 
       FIG. 19  is a top view of the transverse sight mount. 
       FIG. 20  is a posterior to anterior view of the transverse sight mount. 
       FIG. 21  is an anterior to posterior view of the horizontal compact periscope. 
       FIG. 22  is a posterior to anterior view of the horizontal compact periscope. 
       FIG. 23  is a top view of the horizontal compact periscope. 
       FIG. 24  is a top view of the horizontal compact periscope with cut-away sections showing mirror mounts. 
       FIG. 25  is a side and end view of the front stabilizer pivot bolt. 
       FIG. 26  is a side and end view of the stock adaptor pivot pin. 
       FIG. 27  is a side and end view of the locking pin assembly used in the stock adaptor, the transverse sight mount, and the front stabilizer assembly. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Turning now to the drawings, the minimum exposure weapon embodying the present invention is indicated generally by the reference numeral  10  in FIG.  1 . This zero exposure weapon  10  is in the conventional mode in FIG.  1 . In the conventional mode, the stock  14  is in the collapsed position on stock extension  16  and is captured in this position by the lock pin  18 . the stock extension  16  is in line with respect to the stock adaptor  20  and locked in place with the lock pin  36 . The stock adaptor  20  is mounted to the lower receiver  30 , utilizing the additional threaded area on the buffer tube  22  and the locking nut  24 . The transverse sight mount  26  is mounted to picatinny rail on the upper receiver  28 . 
   Further examination of  FIG. 1  shows that the front stabilization assembly  32  is attached to a picatinny accessory mount on the forward hand guard  34 , utilizing the front stabilization mount  38 . In the conventional mode, the front stabilizer assembly  32  is in line with the weapon  10  and is locked in position with the lock pin  40 . 
   The minimum exposure weapon is comprised of an existing weapon with its stock and buffer tube removed. The buffer tube is replaced with a buffer tube  22  which has been manufactured with an additional length of threads which will act as a bolt, and with the accompanying locknut  24  the stock  14 , stock extension  16  and stock adaptor  20  are mounted to the receiver. The front stabilization group ( 38 ,  40 , and  32 ) is attached to the front hand guard. Finally, the transverse sight mount  26  is connected to the upper receiver  28 . 
   Reference FIG.  2 . When the shooter determines he needs cover or protection from possible enemy fire, the zero exposure weapon  10  in  Fig.2  is converted to the minimum exposure mode. The stock  14  has been extended to the rear on the stock extension  16  by depressing the locking pin  18  release lever  42  and extending the stock  14 . The pivot locking pin  36  releases the stock extension  16  and allows the stock extension  16  to rotate around pivot pin  44 , where locking pin  36  locks stock extension  16  at the required angle. User-carried horizontal compact periscope  46  is installed in the rail mount slot  48  ( FIG. 1 ) of transverse sight mount  26  (FIG.  1 ), using the bottom accessory rail  50  ( FIG. 21 ) on the horizontal compact periscope  46 , and is locked in place by the transverse sight mount locking pin  52  (FIG.  18 ). The front stabilizer assembly is rotated about the pivot pin  54  ( FIG. 11 ) in the front stabilizer mount  38 . The locking pin  40  ( FIG. 1 ) uses detent  58  ( FIG. 11 ) and when released from detent  58  (FIG.  11 ), the front stabilizer assembly  32  can rotate bilaterally. Two shock absorber grippers  56  are mounted to the distal end of the front stabilizer assembly  32 . the shock absorber grippers  56  provide for shock reduction during recoiling. When the user is in position behind a wall, he leans into the weapon and the shock absorber grippers  56  make contact with the wall. During the recoil process, the weapon is pinned between the shooter and the wall. The force is initially transmitted to the shooter, but because the shooter is leaning into the weapon stock  14 , some of the force is transmitted through the weapon  10  via the front stabilization assemble  32  and the shock absorber gripper assembly  56  into the wall. Basically, the shock absorber gripper assembly  56  will absorb some of the shock or jarring which would cause excessive wear to the weapon and excessive jarring to the shooter. 
     FIGS. 3A ,  3 B and  4  detail the rear stock  14 . Locking pin  18  is secured in stock housing by the locking pin nut  19 . Spring  17  provides the means to hold locking pin  18  into one of the detents  60  ( FIG. 6 ) on the stock extension  16  (FIG.  2 ). Lever  42  releases locking pin  18  from one of the detent  60  ( FIG. 6 ) to reposition the rear stock  14 . 
     FIGS. 5 ,  6  and  7  detail the stock extension  16 . The plurality of detents  60  are located to specific location for locking and positioning of the collapsible stock  14  ( FIG. 3A ) into the desired position, utilizing locking pin  18  (FIG.  3 ). Track  62 , in conjunction with locking pin  18  (FIG.  3 B), maintains stock  14  ( FIG. 3 ) on receiver extension  16  (FIG.  1 ). Orifice  64  is penetrated by pivot pin  44  ( FIG. 2 ) to allow rotation or pivoting of the entire stock assembly. Locking pin  36  ( FIG. 2 ) will reside and lock in one of three detents,  70 ,  68  or  66 , depending upon whether the stock assembly is locked to the right, centered, or to the left, respectively. 
     FIGS. 8 ,  9 , and  10  detail the previously discussed stock adaptor  20  (FIG.  1 ). The feature not previously discussed is the oval protrusion  72  which penetrates an orifice contained on the lower receiver to maintain correct orientation of the stock adaptor  20 , thus the entire stock assembly. 
     FIGS. 11 ,  12  and  13  detail the front stabilizer mount pivot bolt  54 , allowing pivoting of the front stabilizer assembly  32  ( FIGS. 14 ,  15  and  16 ) through hole  74  (FIGS.  15  and  16 ). Detent  58  ( FIG. 11 ) interfaces with locking pin  40  ( FIG.14 ) to either allow the front stabilizer  32  to rotate to the right or to the left, or to be locked in the center or neutral position. 
     FIGS. 14 ,  15  and  16  further detail the front stabilizer assembly  32 , has a bottom mounted rail  76  in which a handgrip  78  ( FIG. 1 ) is mounted.  FIG. 15  details the shock absorber gripper  56 , which is screwed into the distal end of the front stabilizer assembly  32 . A threaded hole  80  houses the locking pin  40 . 
     FIGS. 17A and 17B  detail the improved buffer tube and locking nut. 
     FIGS. 18 ,  19 , and  20  detail the transverse site mount which is mounted to the upper receiver picatinny rail by the bottom rail receptacle  82 . The upper rail receptacle  84  accepts the horizontal compact periscope  46  ( FIG. 2 ) accessory mount  50  ( FIGS. 21 ,  22 ) and locking pin  52  interfaces with detent  86  ( FIGS. 22 and 23 ) and the horizontal compact periscope  46 . 
     FIGS. 21 ,  22 ,  23 , and  24  detail the horizontal compact periscope  46 . the basic construction consists of two windows,  88  and  90  (FIGS.  21  and  22 ), two mirror mounts,  92  and  94 , ( FIG. 24 ) seen on the cut-away view of  FIG. 24 , attached with 2 mirrors  96  (FIG.  24 ). The detent  86  (FIG.  22 ), in conjunction with the transverse sight mount  26  lock pin  52  (FIG.  18 ), properly aligns the horizontal compact periscope. Basically, the periscope will allow the operator to sight the rifle from the upper receiver sight  98  ( FIG. 2 ) to the far sight. the advantage of this system allows for the user to remove and install the horizontal compact periscope without disturbing the alignment of the rifle  10  based sighting system. 
     FIG. 25  details the pivot bolt  54  which is mounted in the front stabilizer mount (FIG.  11 ).  FIG. 25  details the pivot pin  44  which is mounted in the stock adaptor  20  (FIG.  8 ).  FIG. 27  details the locking pins  36 ,  40  and  52  which are used in the stock adaptor  20  (FIG.  8 ), the front stabilizer  32  (FIG.  14 ), and the transverse sighting mount  26  (FIG.  18 ).