Abstract:
A mounting assembly for attaching an accessory to a dovetail rail interface comprising a mount body, a boss formation extending from a side of the mount body, and a clamping assembly received within the boss formation. The clamping assembly including a camming foot and an actuator arm affixed to the camming foot where rotation of the actuator arm causes rotation of the camming foot. The clamping assembly is movable between an engaged position and a disengaged position. The mounting assembly further includes a spring biased latching assembly configured and arranged to selectively retain said clamping assembly in said engaged position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is related to and claims priority from earlier filed U.S. Provisional Patent Application No. 60/909,956, filed Apr. 4, 2007. 

   BACKGROUND OF THE INVENTION 
   The present invention relates generally to quick detach mounting assemblies for combat weapons such as the modular integrated accessory systems found on most modern combat weapons. More specifically, the present invention relates to a quick detach mounting assembly including a latching assembly that prevents accidental rotation of the actuator arm when the mounting assembly is installed onto the weapon. 
   As the field of combat and commercial weaponry expands, numerous add-on enhancements have become available for attachment to standard firearms, thereby significantly upgrading the capability of the firearm. Of particular interest in the area of combat weapons is the well-known M16/M4 weapon system (M16 and M4 are trademarks of Colt Defense, Inc.). The M16 has been in service for a number of years and will continue to be a popular rifle both in U.S. and foreign militaries for the foreseeable future. Generally, the M16/M4 weapon  2 , as depicted in  FIG. 1 , includes a lower receiver  4 , upper receiver  6 , butt stock  8 , and barrel  10 . 
   The newer models of the M16/M4 weapons further include a mil-std 1913 dovetail rail  12  extending along the top of the upper receiver. These configurations are generally referred to as flat-top receivers. This integrated receiver rail  12  provides a convenient mounting point for many types of enhancement devices such as scopes and other sighting devices. However, space on the upper receiver rail  12  is limited, and many military personnel often have multiple sighting devices that are each tailored to perform in different combat situations. In addition, there are a variety of lighting devices, handgrips, etc. that could also be attached to the weapon for enhanced use of the weapon. The difficulty is that there is simply not enough space on the integrated rail provided on the upper receiver to accommodate all of the desired accessories. Accordingly, the increasing development and refinement of laser sights, infrared lighting, visible lighting, night vision, and specialized scopes and magnifiers, and other accessories continues to drive the need for versatile and reliable integration systems that include additional mil-std 1913 dovetail rails positioned above or around the barrel of the weapon that can support this important equipment and yet stand the test of rugged military use and abuse. 
   Responding to this need, the applicant has developed a modular integrated rail system (A.R.M.S.® S.I.R.® system), which has been well received by the military and has become popular with several branches of the military (See  FIG. 2 ) (A.R.M.S.® and S.I.R.® are registered trademarks of Atlantic Research Marketing Systems, Inc.). The A.R.M.S. S.I.R. system is fully described in U.S. Pat. No. 6,490,822, the entire contents of which are incorporated herein by reference. These modular integrated rail systems for combat weapons  2  generally include an upper hand guard  14 , a means  16  for securing the upper hand guard  14  to the weapon  2 , a lower firearm accessory  18  (in most cases this is a lower hand guard), various optional rail segments, and in many cases, a sling swivel  20  for attaching a shoulder sling to carry the weapon  2 . 
   The upper hand guard  14  is the main structural element of the system. The upper hand guard is  14  generally semi-cylindrical in shape and has a forward end and a rearward end and a mil-std 1913 dovetail rail  22  extending longitudinally between the forward end and the rearward end. The semi-cylindrical upper hand guard  14  further includes symmetrically opposing side walls that extend outwardly and downwardly from the dovetail rail and terminate in symmetrically opposing longitudinally extending mounting channels. The mounting channels are used to mount various accessories, such as a lower hand guard  18  or a grenade launcher, to the upper hand guard  14 . 
   An interface means  16  is provided at the rearward end of the upper hand guard  14  to removably secure the upper hand guard  14  to the firearm  2 . In the original S.I.R. system as shown in U.S. Pat. No. 6,490,822, the clamp is an elongated clamping rail that secures the upper hand guard  14  to the dovetail rail  12  on the top of the upper receiver  6  of the weapon  2 . In the newer S.I.R. systems, the interface means is a U-shaped yoke or clamp that secures the upper hand guard  14  directly to the barrel nut. 
   As is well known in this area, field modification of weapons is critical in combat situations. For example, it may be desired to swap the lower hand guard for a grenade launcher, which can be attached to the upper hand guard, or to add an optional rail segment for securing an added accessory. Similarly, there may be a desire to exchange various different sights or lighting accessories that are mounted on the various dovetail rails positioned around the weapon. In this regard standardized mounting assemblies have been developed to allow quick and easy removal and mounting of these devices relative to the dovetail rails. Such an attachment device was disclosed in U.S. Pat. No. 5,276,988, issued on Jan. 11, 1994 to the present applicant, the contents of the &#39;988 patent being incorporated herein by reference. Generally, the prior art attachment assemblies included a main body having a lower portion that is configured to engage the dovetail rail found on most modern combat weapons and an upper portion that can take on a variety of configurations depending on the accessory that is to be mounted thereon. The lower portion of the mounting assembly has a first engagement member extending downwardly along one side thereof for engaging one side of the dovetail rail. Further, a boss formation is provided adjacent the side of the main body to receive a clamping assembly that is particularly suited to be releasably engagable with a second side of the dovetail rail such that the clamping assembly cooperates with the first engagement member to retain the modular mounting assembly in its installed position on the dovetail rail. 
   One difficulty with the prior art attachment assemblies is that the potential exists for accidental operation (rotation) of the actuator arm resulting in dislodgement of the mount (and the attached accessory) from the weapon. For example, the potential existing for the actuator arm to become snagged on brush or branches during operations in heavily wooded or jungle areas, and accidentally rotated causing dislodgement of the mounting assembly. While the existing spring tension of the clamping assembly is generally more than adequate to retain the actuator arm in the engaged position, it is critically important that the mount stay on the weapon. 
   Accordingly, there is a perceived need for an improved quick detach mount that includes a latching assembly that prevents accidental rotation of the actuator arm even under the harshest environmental conditions. 
   BRIEF SUMMARY OF THE INVENTION 
   In this regard, the present invention provides for an improved mounting assembly that is configured to be releasably attached to a standard dovetail rail profile and that includes a latching assembly for selectively retaining the actuator arm in the engaged position. 
   The mounting assembly of the present invention is particularly suited for use in connection with any firearm that utilizes a standard dovetail rail system. The mounting assembly is configured in the same manner as a traditional prior art mounting interface devices and includes a lower clamping portion that engages the dovetail rail found on most modern combat weapons and an upper accessory interface portion that can take a variety of configurations depending on the accessory that is to be mounted thereon. 
   The mounting assembly includes a mount body and a boss formation that extends from one side thereof. A clamping assembly that includes a camming member having a foot and a shaft extending upwardly therefrom is installed into the boss formation such that the foot of the camming member is received in a position adjacent the bottom of the mounting assembly body and the shaft extends upwardly through the boss formation. An actuator arm is installed onto the top end of the shaft adjacent the top of the boss formation in a manner that engages the shaft and provides a means for the user to rotate the shaft and the foot such that the foot can be engaged and disengaged with the dovetail rail to hold the mounting assembly on the dovetail rail. 
   The mount further includes a latching assembly for selectively retaining the actuator arm in the engaged position. The latching assembly comprises a latch body, a spring and a captivating screw with a head. The latch body includes a seat on one end for receiving the elbow of the actuator arm, and an actuator post on the other end. The actuator post extends upwardly through a guide hole in the body of the mount adjacent the actuator arm and is slidably movable therein between an upper engaged position and a lower disengaged position. The spring is received over the exposed upper end of the actuator post and the captivating screw is secured to the upper end of the actuator post. The spring is thus captivated between the upper surface of the mount body and the lower shoulder of the head of the captivating screw. The spring normally biases the head of the captivating screw in an upward direction, thus drawing the seat of the latch body upwardly into engagement with the elbow of the actuator arm. A front wall of the seat sits in front of the actuator arm and prevents accidental rotation while engaged. When it is desired to rotate the actuator arm, the operator simply depresses the latch body by pressing down on the head of the captivating screw moving the entire latch body downwardly and disengaging the seat from the elbow of the actuator arm. 
   Accordingly, it is an object of the present invention to provide an improved mounting assembly that allows for the releasable mounting of various accessories onto the standard dovetail rail found on modern combat weapons. 
   Further, it is an object of the present invention to provide a mounting assembly that can be reliably mounted onto a dovetail rail while including a spring biased latching assembly for selectively retaining the actuator arm in the engaged position. 
   These, together with other objects of the invention, along with various features of novelty that characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings which illustrate the best mode presently contemplated for carrying out the present invention: 
       FIG. 1  is a side view of a prior art combat firearm; 
       FIG. 2  is a perspective view of a prior art rail interface system; 
       FIG. 3  is a perspective view of the mounting assembly of the present invention; 
       FIG. 4  is an exploded perspective view thereof; 
       FIG. 5  is a top view thereof with the actuator arm and latching assembly in the engaged position; 
       FIG. 6  is a top view thereof with the actuator arm in the disengaged position; 
       FIG. 7  is a side view thereof with the latching assembly in the engaged position; and 
       FIG. 8  is a side view thereof with the latching assembly in the disengaged position to allow rotation of the actuator arm. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Now referring to the drawings, the mounting assembly is shown and generally illustrated at  30  in  FIGS. 3-7 . The mounting assembly  30  is configured to be releasably attached to a standard dovetail rail profile  22  as is depicted in  FIGS. 1 and 2 . 
   Turning now to  FIG. 3 , as can be seen, the mounting assembly  30  includes a main body  31  that is configured in substantially the same manner as a traditional prior art device and further includes a lower portion  32  that is configured to engage the dovetail rail found on most modern combat weapons and an upper portion  34  that can take on a variety of configurations depending on the accessory that is to be mounted thereon. The lower portion  32  of the mounting assembly has a first engagement member  36  extending downwardly along one side thereof for engaging one side of the dovetail rail. Further, a boss formation  38  is provided adjacent the side of the main body  31  wherein the boss formation  38  includes an opening  40  therein to receive a clamping assembly  42 . 
   The clamping assembly  42  is particularly suited to be releasably engagable with a second side of the dovetail rail such that the clamping assembly  42  cooperates with the first engagement member  36  to retain the modular mounting assembly  30  in its installed position on the dovetail rail. It is preferred that the clamping assembly  42  be rotatably movable between an engaged position wherein the clamping assembly  42  engages the second side of said dovetail rail and cooperates with the first engagement member  36  on the lower portion  32  of the modular mounting assembly  30  to retain the mounting assembly  30  on the dovetail rail, and a disengaged position wherein the clamping assembly  42  is disengaged, thereby allowing the mounting assembly  30  to be removed from the dovetail rail. 
   In a preferred embodiment the clamping assembly  42  includes a camming member  43  having a foot  44  and a shaft  46  extending upwardly therefrom such that the shaft  46  is installed into the opening  40  in the boss formation  38  on the mounting assembly  30 . Further, to enhance the overall fit and rotation of the clamping assembly  42 , a bushing  48  may also be provided in the opening  40  between the boss formation  38  and the shaft  46 . Once the shaft  46  is inserted into the opening  40  in the boss formation  38 , the foot  44  is received in a position adjacent the bottom surface of both the boss formation  38  and the mounting assembly  38  itself. An actuator arm  50  is installed onto the top end of the shaft  46  and is received adjacent the top of the mounting assembly  30 . The actuator arm  50  engages the shaft  46  and provides a means for the user to rotate the shaft  46  and the foot  44  allowing the foot  44  to be engaged and disengaged with the second side of the dovetail rail. In this manner, the clamping assembly  42  and the first engagement member  36  cooperate to hold the mounting assembly on the dovetail rail. 
   There is also shown generally a buffer element  52  having a flat horizontal base portion with an arm  54  at each end of the base extending upwardly at an oblique angle of 135 degrees. The free end of each arm is curved approximately 150 degrees. Two side-by-side openings  56 , corresponding in separation to the separation between buffer element  52  arms  54 , are formed in the mounting assembly  30 . The arms  54  on the top of the buffer element  52  are slid through the openings  56  thereby retaining the buffer element  52  in the mounting assembly  30 . In this arrangement, the buffer element  52  is positioned between the surface of the dovetail rail and the foot  44  of the clamping assembly  42 . Rotation of the actuator arm  50 , the shaft  46  and in turn the foot  44  serves to press the buffer element  52  into the side of the dovetail rail. By placing the buffer element  52  in this position, the buffer element  52  prevents the foot  44  from directly touching and thereby scratching the dovetail rail. The buffer element  52  further distributes the clamping pressure over a greater area and prevents distortion of the aluminum dovetail rail  22 . 
   An indexing shoulder formation  56  is provided on the boss formation  38 . The shoulder  56  extends upwardly from the boss formation  38  and is positioned in such a manner that the shoulder  56  prevents over rotation of the actuator arm  50 . The front face  58  of the shoulder  56  acts as a positive stop for the actuator arm  50  once it reaches the fully open/disengaged position (See  FIG. 6 ). The shoulder  56  is illustrated as being a monolithically formed component that is milled integrally with the boss  38 . It should be appreciated by one skilled in the art that the shoulder  56  may also be formed by installing a separately machined object such as a pin, a wedge, a block or the like onto the boss  38  to prevent further rotation of the actuator  50  past a fully disengaged position. 
   The mount  30  further includes a latching assembly generally indicated at  60  for selectively retaining the actuator arm  50  in the engaged position. The latching assembly  60  comprises a latch body  62 , a spring  64  and a captivating screw  66  with a head  68 . 
   The latch body  62  includes a seat  70  on one end for receiving the elbow portion or forearm portion of the actuator arm  50 , and an actuator post  72  on the other end. The actuator post  72  extends upwardly through a guide hole  75  ( FIG. 4 ) in the body  31  of the mount adjacent the actuator arm  50  and is slidably movable therein between an upper engaged position ( FIGS. 1 ,  5 ,  6 , and  7 ) and a lower disengaged position ( FIG. 8 ). The spring  64  is received over the exposed upper end of the actuator post  72  and the captivating screw  66  is secured to the upper end of the actuator post  72 . The threaded shaft of the captivating screw  66  is received into a threaded opening  74  in the end of the actuator post  72 . The spring  64  is thus captivated between the upper surface of the mount body  31  and the lower shoulder of the head  68  of the captivating screw  66 . The spring  64  normally biases the head  68  of the captivating screw  66  in an upward direction, thus drawing the seat  70  of the latch body  62  upwardly into engagement with the elbow of the actuator arm  50 . The seat portion  70  includes a contoured surface  76 , which conforms to the curved elbow portion of the actuator arm  50 . A front wall  78  of the seat  70  sits in front of the actuator arm  50  and prevents accidental rotation while engaged. When it is desired to rotate the actuator arm  50 , the operator simply depresses the latch body  62  by pressing down on the head  68  of the captivating screw  66  moving the entire latch body  62  downwardly and disengaging the seat from the elbow of the actuator arm ( FIG. 8 ). When the latch body  62  is in the lower position ( FIG. 8 ) the actuator arm is free to rotate into its own disengaged position. 
   Accordingly, it can be seen that the present invention provides a unique and novel modular accessory mount that fills a critical need for soldiers in the field by ensuring positive and reliable operation. The latching assembly  60  provides a simple solution, which can prevent accidental loss of critical equipment in the field. For these reasons, the instant invention is believed to represent a significant advancement in the art, which has substantial commercial merit. 
   While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claims.