Patent Publication Number: US-11035646-B2

Title: Grenade launcher with modular interface

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority benefit of U.S. Provisional Application No. 62/783,738 filed Dec. 21, 2018. The aforementioned application is incorporated herein by reference in its entirety. 
    
    
     INCORPORATION BY REFERENCE 
     This application is related to U.S. Provisional Application No. 62/085,967, filed Dec. 1, 2014, and U.S. Non-Provisional application Ser. No. 14/955,363, filed Dec. 1, 2015. Each of the aforementioned applications is incorporated herein by reference in its entirety. 
     BACKGROUND 
     The present invention relates generally to a modular grenade launcher system which provides quick attachment and removal from a firearm and/or firearm accessory rail sections. In certain embodiments, the modular grenade launcher system herein may be used in configuration with a firearm, e.g., in an underslung configuration, or, in other embodiments, as a standalone weapon. 
     SUMMARY 
     In one aspect, a grenade launcher system comprises a grenade launcher receiver and a grenade launcher barrel attached to the grenade launcher receiver. A trigger assembly is attached to the grenade launcher receiver at a position adjacent the grenade launcher barrel. The grenade launcher receiver has an elongate channel disposed on an upper surface of the grenade launcher receiver, the elongate channel extending parallel to the grenade launcher barrel and configured to slidably and removably receive a mounting rail. 
     In a more limited aspect, the mounting rail is selected from the group consisting of an accessory rail of a firearm and a stock rail of grenade launcher stock. 
     In another more limited aspect, the mounting rail is an accessory rail disposed on a lower hand guard portion of an assault rifle. 
     In yet another more limited aspect, the accessory rail is a Picatinny rail interface. 
     In another more limited aspect, the grenade launcher system further comprises one or more locking fasteners on the receiver for securing the mounting rail in a fixed position within the elongate channel. 
     In another more limited aspect, the grenade launcher system further comprises a ladder sight assembly and one or more tapped openings disposed on the receiver, the one or more tapped openings having internal threads receiving threaded fasteners for removably attaching the ladder sight assembly to the grenade launcher receiver. 
     In yet another more limited aspect, the ladder sight assembly includes a base portion with a front sight and a rear ladder sight axially spaced apart from the front sight. 
     In still another more limited aspect, one or both of the front sight and the rear ladder sight is pivotally attached to the base portion to permit one or both of the front sight and the rear ladder sight to be folded down when not in use. 
     In another more limited aspect, the grenade launcher system of claim  1 , further comprises a ladder sight assembly, one or more tapped openings disposed on a first transverse side of the receiver, the one or more tapped openings having internal threads receiving threaded fasteners for removably attaching the ladder sight assembly to the first transverse side of the receiver, and one or more tapped openings disposed on a second transverse side of the receiver, the one or more tapped openings having internal threads receiving threaded fasteners for removably attaching the ladder sight assembly to the second transverse side of the receiver. 
     In another more limited aspect, the grenade launcher system further comprises a ladder sight assembly configured to be removably attached to the firearm. 
     In another more limited aspect, the grenade launcher system further comprises a pistol grip attached to the grenade launcher receiver adjacent the trigger assembly. 
     In yet another more limited aspect, the pistol grip includes a main grip portion and a removable grip portion, wherein the removable grip portion is removably attached to the main grip portion. 
     In still another more limited aspect, the grenade launcher system is configured for removable attachment to a firearm having a magazine well, and the main grip portion has a size and shape to provide clearance beneath the magazine well to permit insertion and removal of a magazine in the magazine well without interference by the pistol grip when the grenade launcher system is attached to the firearm. 
     In yet another more limited aspect, the pistol grip portion is removably attached to the grenade launcher receiver. 
     In another more limited aspect, the barrel is pivotally attached to the grenade launcher receiver at or near a muzzle end of the barrel to allow a breech end of the barrel to pivot away from the receiver. 
     In yet another more limited aspect, the grenade launcher system further comprises a latch mechanism on the grenade launcher receiver for selectively locking the grenade launcher barrel with respect to the grenade launcher receiver to prevent pivoting movement of the grenade launcher barrel and unlocking the grenade launcher barrel with respect to the grenade launcher receiver to allow pivoting movement of the grenade launcher barrel. 
     In another more limited aspect, the grenade launcher system further comprises a grenade launcher stock assembly, the grenade launcher stock assembly including a stock rail and a shoulder support. The stock rail has a first end and a second end opposite the first end. The first end is configured to be slidably received within the elongate channel, wherein the shoulder support is attached to the second end. 
     In yet another more limited aspect, the grenade launcher system, further comprises at least one toggle clamp for selectively locking and unlocking the stock rail, wherein a position of the stock rail within the elongate channel is slidably adjustable when the at least one toggle clamp is unlocked and wherein the position of the stock rail is fixed when the at least one toggle clamp is locked. 
     In another more limited aspect, the grenade launcher system further comprises a firing mechanism operably coupled to the trigger assembly. 
     In yet another more limited aspect, the firing mechanism is integral with one of the receiver and a pistol grip attached to the grenade launcher receiver. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the invention. 
         FIG. 1  is a side view of an exemplary embodiment grenade launcher system herein attached to an assault rifle. 
         FIG. 2  is a top view of the grenade launcher system appearing in  FIG. 1 . 
         FIG. 3  is a side view of a modular grenade launcher embodiment configured for a standalone operation. 
         FIG. 4  is an isometric view of the modular grenade launcher embodiment appearing in  FIG. 3 , where the ladder sight assembly is positioned on the right side of the receiver, the breech end of the barrel is pivoted to the left of the trigger assembly, and the shoulder support is in an extended position. 
         FIG. 5  is an isometric view of the grenade launcher embodiment appearing in  FIG. 3 , where the ladder sight assembly is configured on the left side of the receiver and the shoulder support is in a retracted position. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, an exemplary modular grenade launcher system  100  attached to a firearm  104  appears in  FIGS. 1 and 2 , i.e., in an under-barrel configuration.  FIGS. 3-5  illustrate a standalone grenade launcher configuration. The firearm to which the modular grenade launcher is to be attached may be any military or tactical assault weapon having a tactical accessory rail/hand guard  108 , including for example, M4, AR15, or M16 assault weapons. Exemplary firearm accessory rails include Picatinny (e.g., MIL-STD-1913, STANAG-2324) rails and the like. In certain embodiments, when the grenade launcher system is attached to a firearm, the grenade launcher system  100  is secured to a lower rail portion  112  of the hand guard  108  for such firearm. 
     Turning now to  FIG. 3 , the grenade launcher system  100  includes a receiver  116  configured for attachment to the lower rail  112 . The receiver  116  comprises a groove  120  extending along its upper surface complementary with, and configured to slidably receive, the lower rail  112 . One or more fasteners  124  are provided on the receiver  116  to secure the rail  112  within the channel  120  (see  FIG. 5 ). In certain embodiments, the one or more locking fasteners  124  are one or more toggle clamps comprising a pivoting lever  128 , e.g., with an eccentric or off-center pivot axis  130  to define a cam surface, which can be pivoted between a locked and unlocked position to selectively secure and release the receiver  116  with respect to the lower rail  108 . 
     In certain embodiments, the receiver  116  includes one or more mounting bosses  132  having threaded openings  134  which receive corresponding threaded fasteners  136  for attaching a ladder sight assembly  140 . The ladder sight assembly  140  includes a base portion  144  with a front sight  148  and a rear ladder sight  152 . In certain embodiments, the rear ladder sight  152  is pivotally attached to the rearward end of the base portion  144  via a rear hinge or hinge pin  156  to permit the rear ladder sight  152  to be folded down when not in use. In certain embodiments, the front sight  148  is pivotally attached to the forward end of the base  144  via a front hinge  160  to permit the front sight  148  to be folded down when not in use. It will be recognized, however, that one or both of the front sight  148  and rear ladder sight  152  may be fixed or nonfolding. The base portion  144  of the ladder sight assembly is secured to the receiver via the threaded fasteners  136  engaging the threaded bosses  132 . In certain embodiments, threaded bosses  132  are provided on both the left side and right side of the receiver  116  to permit the ladder sight assembly  140  to be removably and selectively attached to either the left or right side of the receiver  116  in accordance with the preference of the grenadier. 
     In certain embodiments, when the modular grenade launcher system  100  is mounted to the firearm  104 , for example, in an underslung configuration as shown in  FIGS. 1 and 2 , the ladder sight assembly  140  may be configured to removably attach to a rail portion of the handguard  108 . The ladder sight assembly may be attached to the tactical rail assembly, e.g., by means of a rail clamp adapter having threaded bosses or other mechanical fasteners. 
     In certain embodiments, the receiver  116  houses a firing mechanism (not shown), e.g., for actuating a firing pin which strikes the primer of a cartridge responsive to a trigger pull, is housed within the receiver  116  and is operatively coupled to a trigger  172 . In certain embodiments, the trigger  172  is coupled to the firing mechanism via a mechanical linkage. In certain alternative embodiments, the trigger  172  is operably connected to the firing mechanism via an electrical or electromechanical linkage. 
     Commonly, under-barrel grenade launchers lack a pistol grip, wherein a magazine (not shown) inserted into the magazine well  184  of the firearm  104  serves as a handgrip when operating the grenade launcher. In certain embodiments, the receiver  116  also includes a handgrip, such as a pistol grip,  168  attached thereto. In certain embodiments, the pistol grip  168  is removably attached to the receiver  116 . 
     In certain further embodiments, the pistol grip  168  includes a main grip portion  176  and a removable grip portion  180 , wherein the removable grip portion  180  is removably attached to the main grip portion  176  for adapting the grenade launcher system  100  for use as a standalone weapon and removed from the main grip portion  176  when used as an under-barrel system mounted to a firearm. When the grenade launcher system  100  is being used in the firearm-mounted configuration, the removable grip portion  180  may be removed, as illustrated in  FIGS. 1 and 2 . In this manner, clearance beneath the magazine well  184  of the firearm  104  is provided to permit insertion of a magazine into the magazine well without interference by the pistol grip when used in the under barrel configuration while providing a larger or more ergonomic pistol grip configuration when used in the standalone configuration. 
     In certain embodiments, the entire pistol grip portion  168 , including both the main grip portion  176  and the removable grip portion  180  is configured to be removed from the modular grenade launcher  100  when used in the underslung configuration and attached when the grenade launcher system  100  is being used in a standalone configuration. 
     The grenade launcher system  100  further includes a barrel  188 , which is pivotally attached to the receiver  116 . In certain further embodiments, the barrel  188  includes a hand guard portion  192 . In certain embodiments, the barrel  188  is configured to selectively pivot at or near the muzzle end  196  to allow the rear or breech end  200  of the barrel  188  to pivot relative to the receiver  116  for removing a spent cartridge casing of a fired round and to load another cartridge round for firing. In certain embodiments, pivoting movement of the barrel  188  is actuated by manually sliding a latch release mechanism  204 . In certain embodiments, the barrel pivot mechanism may be as described in commonly owned U.S. application Ser. No. 14/955,363 to allow the rearward end of the barrel assembly to selectively pivot away from the firing mechanism to either the left or the right, as desired by the user, e.g., based on the handedness of the operator, for the purpose of chambering another round. In other embodiments, the breech end of the barrel is configured to pivot away from the firing mechanism in a single mechanism only, e.g., to the left side as in the embodiment illustrated in  FIGS. 2 and 4 . 
     With reference now to  FIGS. 3, 4, and 5 , the modular grenade launcher system  100  herein appears in a configuration for use as a standalone weapon, i.e., without an associated firearm. The standalone configuration includes a removable stock assembly  208  comprising a stock sliding rail  212  and shoulder support  216 . The sliding stock rail  212  is slidably received within the channel  120 . When the toggle clamps  128  are in the unlocked position, the sliding rail  212  can be slid to the forward most position as shown in  FIG. 5  secured by locking the toggle clamps  128 , e.g., for storage and transport. During operation, the toggle clamps  128  are moved to the unlocked position and the sliding rail  212  is slid a desired distance rearward to move the shoulder support  216  to a desired position in accordance with the user&#39;s size and preference. The sliding rail  212  is then secured at the desired position by moving the toggle clamps  128  to the locked position. 
     The invention has been described with reference to the preferred embodiment. Modifications and alterations will occur to others upon a reading and understanding of the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims and equivalents thereof.