Patent Publication Number: US-9835394-B2

Title: Charging handle for a firearm with angled latch

Description:
RELATED APPLICATION 
     This application claims priority to U.S. provisional patent application Ser. No. 62/056,826 filed on Sep. 29, 2014, the contents of which are fully incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention is directed to a charging handle including a latch having an angled surface that contacts an upper edge of the latch pocket such that the charging handle disengages by rearward force alone. 
     BACKGROUND OF THE INVENTION 
     Professional military and law enforcement need more versatility in the operation of charging AR style weaponry. Prior art charging handles are known to provide a latch which locks the charging handle in its fully forward position. There have been many upgrades to this design, but most designs have centered about a latch which must be manually released by an operator prior to movement of the charging handle and are not capable of disengagement solely by rearward force alone. 
     Operation of an AR rifle relies on gas pressure siphoned from its barrel during live fire. This gas pressure is released into the upper receiver in a reduced state during the cycle of the weapon. Further, this gas pressure exerts some force against the combined surface on the charging handle with a net rearward impulse resulting. It is this rearward impulse that the latch must counter. 
     During operation, forces within the upper receiver act to apply a force against the charging handle in the rearward direction. A charging handle must not move during the operation of the AR rifle (or weapon) in live fire. 
     A prior art conventional military specification (mil spec) design charging handle  6  is illustrated in  FIG. 1 . Charging handle  6  is positioned fully forward in an upper receiver  3 . A charging handle latch  7  is engaged with a charging handle latch pocket  202  of upper receiver  3 . Charging handle  6  is held in place by a pivotable charging handle latch  7  that pivots about a fulcrum pin  8  in relationship to a compression spring  9  and the charging handle latch pocket  202 . Compression spring  9  exerts expanding pressure between a bottom of a spring bore and a spring landing of the charging handle. This force causes a clockwise torque around the fulcrum pin  8 . In turn, this clockwise torque causes an equal and opposite force at the latch surface  200  directed downward into charging handle latch pocket  202  thereby retaining the charging handle  6  in its forward position. 
     Particular to a mil spec design, latch surface  200  of the mil spec latch  7  is flat and parallel to a latch pocket surface  201  of charging handle latch pocket  202  as illustrated in  FIGS. 1 and 2 . To release the mil spec handle  6  for rearward movement, an operator must apply rearward force on a handle surface  203  of mil spec latch  7 . This force must cause counterclockwise torque around fulcrum pin  8  sufficient to overcome the retaining clockwise torque exerted by the compression spring  9 , thus allowing counterclockwise rotation of the mil spec latch  7  about the fulcrum pin  8 . As the mil spec latch  7  rotates, latch surface  200  separates from latch pocket surface  201 , and the charging handle moves rearward. However, an operator cannot apply pressure to an opposite side  204  of the mil spec charging handle  6  to move the handle rearward. The mil spec latch  7  would retain forward location by virtue of the engaged latch surfaces  200 ,  201 . 
     More recently, a charging handle has come onto the market that has a fully rounded latch. In that product, the engaged portion on the latch is fully rounded and drops into its corresponding latch pocket. However, a rounded edge may apply inconsistent force to resist rearward gas impulse. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an improvement to charging handles for firearms over that of known prior art. Particularly, the present charging handle is capable of disengagement from an upper receiver solely by rearward force alone. The charging handle has a base and a substantially perpendicularly-oriented cross-member. The charging handle includes a compression spring biased latch arm with the upper arm including an angled surface that engages with an rearward edge of a latch pocket on the side of an upper receiver. The upper receiver is configured to receive the charging handle cross-member longitudinally of the upper receiver such that the base is fully forward of the upper receiver. 
     The angled charging handle latch engaged with the rearward edge of the upper receiver creates an angle relative to an imaginary center line of the cross-member. That angle is in the range of 34 to 38 degrees, with a preferred angle of 36 degrees. This angled surface of the charging handle latch provides a consistent force to the rearward edge of the upper receiver latch pocket and is better able to resist inherent rearward gas impulse. 
     Claims are directed to both the charging handle and the combination of the charging handle and upper receiver. Further, claims are directed to a method of use for using the charging handle of the present invention. 
     These and other advantages will become more apparent upon review of the drawings, the Detailed Description of the Invention, and the Claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Like reference numerals are used to designate like parts throughout the several views of the drawings, wherein: 
         FIG. 1  is a section view of a prior art mil spec charging handle with a charging pivotable handle latch assembled within a portion of an upper receiver of a firearm; 
         FIG. 2  is an enlarged view of the prior art mil spec charging latch of  FIG. 1  illustrating its flat latch surface, and corresponding latch pocket; 
         FIG. 3  is a front perspective view of the charging handle of the present invention assembled within an upper receiver of an AR rifle; 
         FIG. 4  is a section view taken along lines  4 - 4  of  FIG. 3 ; 
         FIG. 5  is an enlarged view of circle  5  of  FIG. 3 ; 
         FIG. 6  is an enlarged view of circle  6  of  FIG. 4 ; 
         FIG. 7  is an enlarged view of the charging latch, angled latch surface, and the latch pocket of  FIG. 6 ; and 
         FIG. 8  is a perspective view of the charging handle apart from the upper receiver. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The charging handle of the present invention operates with a spring loaded angled charging handle latch which will release under the rearward pressure of the handle, independent of any mechanism for release of the same. To release the latch that retains the handle in its forward position, the operator need only apply rearward pressure to either side of the existing grip surfaces. The latch releases at that point with no need of mechanical intervention. 
     Referring to  FIGS. 3-8 , the present invention is a charging handle  10  having a base  16  and generally perpendicularly-oriented cross member  18  ( FIG. 8 ) having an imaginary center line CL. Normal condition of an uncharged AR style rifle will start wherein the charging handle  10  is fully forward in an upper receiver  30  of a firearm (not illustrated) with a charging handle latch  20  engaged in a charging handle latch pocket  100  of upper receiver  30 . The upper receiver has a first end  32  that is positioned near charging handle base  16 . The upper receiver longitudinally receives the charging handle cross-member  18  ( FIGS. 4, 6, and 8 ). Upper receiver  30  has a side  34  where latch pocket  100  is positioned. Latch pocket  100  includes a base surface  112  that may be parallel to cross member  18  as illustrated in  FIG. 6 . 
     Charging handle  10  is held in place by charging handle latch  20 , and its interrelationship to a compression spring  50 , a fulcrum pin  40 , and charging handle latch pocket  100  that is positioned within a side of the upper receiver. Latch handle  20  has an upper arm  22  and a lower arm  24 . In this uncharged state, compression spring  50  exerts expanding pressure between a bottom  101   a  of a spring bore  101   b  and a spring landing  102  of charging handle latch  20  ( FIG. 6 ). This expanding pressure causes a clockwise torque of lower arm  24  around fulcrum pin  40 . In turn, an equal and opposite force at an angled latch surface  104  of the upper arm  22  of charging handle latch  20  is directed downward into charging handle latch pocket  100 , thereby retaining the changing handle latch  20  in its forward position. 
     Latch pocket  100  further includes a latch pocket surface  105  and an upper rear edge  106  that is configured to engage the angled upper latch arm of the charging handle latch. The upper edge makes contact with the angled latch surface  104 . Rearward edge  106  may be an outwardly-extending protrusion that is best illustrated in  FIG. 5  or a substantially 90 degree corner as illustrated in  FIG. 6 . 
     Latch surface  104  of the charging handle latch  20  is angled relative to a corresponding rearward edge  106  of latch pocket  100  and imaginary centerline CL. Angle α is the angle between angled latch surface  104  and imaginary center line CL. Angle α is in a range of 34-38 degrees with a preferred angle of 36 degrees. This angle range was found to provide a consistent force and is better able to resist rearward gas impulse. 
     During the charging operation, an operator will apply rearward directed force to the charging handle  10  on either of the handle surfaces  107 , or both, depending on style of operation, training taken and whether the operator is left handed or right handed. As the charging handle latch  20  is connected to the charging handle  10  through fulcrum pin  40 , this rearward force translates to a rearward differential force between the latch surface  104  and the upper rearward edge  106  of latch pocket  100 . Referring now to  FIGS. 4 and 7 , since latch surface  104  is angled to latch pocket surface  105  and contacts rearward edge  106  of latch pocket  100 . Rearward edge  106  is a protrusion that is engaged by the angled latch. Rearward edge  106  may be the only contact with the angled latch, as illustrated in enlarged  FIG. 5 . Latch surface  104  slides in a ramping fashion across rearward edge  106  of latch pocket  100 , overcoming the opposing force applied by the compression spring  50 . 
     Compression spring  50  exerts expanding pressure between a bottom of a spring bore and the spring landing of the charging handle. This force causes a clockwise torque around the fulcrum pin  40 . In turn, this clockwise torque causes an equal and opposite force at the latch surface  104  directed downward into latch pocket  100  thereby retaining the charging handle  10  in its forward position. While it is possible to overcome the latching force applied by an operator, the latch applies a consistent force to holding the charging handle in place during normal firing operation. 
     The result of this invention is that the latch and latch surface is angled rather than parallel to the surface of the latch pocket as in the prior art (see e.g.,  FIGS. 1 and 2 ). In the present invention, the charging handle latch engages the latch pocket via the angled relationship of latch surface to latch pocket and relative to the upper edge of the latch pocket. To disengage, the charging handle latch&#39;s latch surface is removed from the latch pocket by virtue of rearward force alone, applied anywhere across the charging handle surfaces. In contrast, the mil spec design requires that the operator disengage latched surfaces in a specific manner prior to operation of the charging handle. 
     The present invention charging handle  10  applies a consistent force to resist the disengagement of the latch along the entire length of engagement between angled latch surface  104  and rearward edge  106  of latch pocket surface  105  of latch pocket  100 . Thus, the charging handle will only move rearward under the influence of the operator and not as a result of the operation of the firearm (weapon). 
     The illustrated embodiments are only examples of the present invention and, therefore, are non-limitive. It is to be understood that many changes in the particular structure, materials, and features of the invention may be made without departing from the spirit and scope of the invention. Therefore, it is the Applicant&#39;s invention that its patent rights not be limited by the particularly embodiments illustrated and described herein, but rather by the following claims interpreted according to accepted doctrines of claim interpretation, including the Doctrine of Equivalents, Doctrine of Claim Differentiation, and Reversal of Parts.