Patent Publication Number: US-11029110-B2

Title: Magazine safety

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims benefit of priority to U.S. Provisional Application No. 62/829,968, filed Apr. 5, 2019, which application is hereby incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to safety mechanisms for semiautomatic pistols. 
     BACKGROUND 
     Magazine safeties prevent a firearm, such as a semiautomatic pistol, from being fired if a magazine is withdrawn (usually even partially withdrawn) from the magazine well of the pistol or other firearm. Magazine safeties are thought to improve the safe handling of firearms, especially for activities related to field stripping and cleaning. Magazine safeties also provide a way to render a firearm inoperable, allowing for safer storage when the magazine is stored separate from the firearm. Furthermore, certain jurisdictions and authorities (notably the state of California, various police departments and government militaries) have enacted legislation or imposed purchasing requirements mandating the use of magazine safeties on firearms sold in the jurisdiction or purchased for use. 
     SUMMARY 
     The invention concerns a safety mechanism for a firearm and a firearm having a safety. The firearm, for example, a semiautomatic pistol has a frame defining a magazine well for receiving an ammunition magazine and a trigger bar movably mounted on the frame. In an example embodiment the safety mechanism comprises a first lever mountable on the frame adjacent to the magazine well. The first lever comprises a first arm pivotable about a first pivot axis into and out of the magazine well, and a second arm positioned on an opposite side of the first pivot axis, A second lever has a first end pivotably attached to the second arm and a second end attachable to the frame. The second end is pivotable about a second pivot axis oriented parallel to the first pivot axis. When the first arm pivots into the magazine well the second lever pivots into a position blocking motion of the trigger bar which would discharge the firearm. 
     An example embodiment further comprises a biasing spring engaging one of the first and second levers for biasing the first arm into the magazine well. In a specific example embodiment the biasing spring acts between the frame and the second lever. By way of further example a spur may extend from the second lever. The spur is engageable with the trigger bar when the first arm pivots into the magazine well. 
     An example embodiment further comprises a pin extending between the second arm and the first end of the second lever. The pin defines a floating axis of rotation between the second lever and the second arm parallel to the first and second pivot axes. 
     In another example safety mechanism and firearm, the safety mechanism comprises a housing mountable on the frame adjacent to the magazine well. A first lever is mounted on the housing. The first lever comprises a first arm pivotable about a first pivot axis into and out of the magazine well, and a second arm positioned on an opposite side of the first pivot axis. A second lever has a first end pivotably attached to the second arm and a second end attached to the housing. The second end is pivotable about a second pivot axis oriented parallel to the first pivot axis. When the first arm pivots into the magazine well the second lever pivots into a position blocking motion of the trigger bar which would discharge the firearm. 
     An example embodiment further comprises a biasing spring engaging one of the first and second levers for biasing the first arm into the magazine well. In a specific example the biasing spring acts between the housing and the second lever. A further example embodiment comprises a spur extending from the second lever. The spur is engageable with the trigger bar when the first arm pivots into the magazine well. An example embodiment further comprises a pin extending between the second arm and the first end of the second lever. The pin defines an axis of rotation parallel to the first and second pivot axes. In an example embodiment the housing comprises at least one plate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a partial sectional view of a semiautomatic firearm having an example magazine safety mechanism according to the invention, the mechanism shown in “fire” status; 
         FIG. 2  shows an isometric view of the example magazine safety mechanism in  FIG. 1 ; 
         FIG. 3  shows a partial section view of the semiautomatic firearm of  FIG. 1  with the example magazine safety mechanism in “safe” status; and 
         FIG. 4  shows an isometric view of the example magazine safety mechanism in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a firearm  10 , in this example a semiautomatic pistol, having a magazine safety mechanism  12  according to the invention. Firearm  10  comprises a frame  14  which defines a magazine well  16  for receiving an ammunition magazine  18 . Fire control in this example is by means of a trigger bar  20  connected between a trigger  22  and a sear (not shown). The firearm  10  is striker fired, but may also be hammer fired by way of further example. 
       FIG. 2  shows the safety mechanism  12  in detail. The example mechanism  12  comprises a first lever  24  mounted on the frame  14 . First lever  24  can be mounted directly onto the frame  14 , or on a housing, comprising a plate  26  for example (see  FIG. 1 ), which is mounted on the frame. The first lever  24  is mounted on frame  14  adjacent to the magazine well  16  and comprises a first arm  28 . First arm  28  is pivotable about a first pivot axis  30  defined by a pin  32  fixed, either directly to the frame  14 , or to the housing (plate  26  in this example). First lever  24  further comprises a second arm  34  positioned on an opposite side of the first pivot axis  30 . A second lever  36  has a first end  36   a  pivotably attached to the second arm  34 . Attachment of the first end  36   a  of the second lever to the second arm  34  is via a floating pin  38  extending between the second lever  36  and the second arm  34 . Pin  38  is said to “float” because it is fixed only to the second lever  36  and the second arm  34  thereby forming a toggle joint which can move in translation relatively to the frame  14  (and the housing, when present). Pin  38  thus defines a floating axis of rotation  40  between the first and second levers  24  and  36 . The second end  36   b  of the second lever  36  is attached to the frame  14 , either directly or via the housing (plate  26 ). Second end  36   b  is pivotable about a second pivot axis  42  defined by a second pin  44  fixed, either directly to the frame  14  or to the frame via the housing (plate  26 ). As it is the purpose of the second lever  36  to contact and thereby block motion of the trigger bar  20  when the magazine  18  is not in the magazine well  16  it is advantageous to provide a spur  46  which extends from the second lever. Spur  46  provides positive mechanical engagement between the second lever  36  and the trigger bar  20  when it is desired to prevent discharge of the firearm  10  as described below. 
     It is advantageous to bias the mechanism  12  so that the first arm  28  is urged to pivot into the magazine well  16  (see  FIGS. 3 and 4 ). As shown in  FIG. 2 , this biasing is effected by a spring  48  acting either between the frame  14  and the second lever  36 , or between the housing (plate  26  for example) and the second lever. A biasing spring could also act between the frame or housing and the first lever  24 . 
     Operation of the example magazine safety  12  according to the invention is illustrated in  FIGS. 1 through 4 .  FIGS. 1 and 2  show the firearm  10  with a magazine  18  in the magazine well  16 . Upon insertion into magazine well  16  the magazine  18  contacts the first arm  28  of the first lever  24  and rotates the first lever counterclockwise about the first pivot axis  30 . The second arm  34  of the first lever  24  is pivotably connected to the first end  36   a  of the second lever  36  via the floating pin  38 , and thus counterclockwise rotation of the first lever  24  causes clockwise rotation of the second lever  36  about the second pivot axis  42 . Clockwise rotation of the second lever  36  positions the spur  46  out of the path of the trigger bar  20 , thereby allowing the trigger bar to move and discharge the firearm  10  upon a pull of trigger  22 . 
       FIGS. 3 and 4  show the magazine safety  12  with the magazine  18  being removed from the magazine well  16 . The absence of the magazine permits the first lever  24  to pivot clockwise about the first pivot axis  30  and into the magazine well  16 . Rotation of the first lever  24  is effected by the biasing spring  48  acting on the second lever  36  via the floating pin  38  connecting first and second levers. The absence of resistance to rotation of the first lever  24  thus permits counterclockwise rotation of the second lever  36  about the second pivot axis  42 . Counterclockwise pivoting motion of the second lever  36  positions the spur  46  in the path of the trigger bar  20 , thereby blocking its motion and preventing discharge of the firearm when there is no magazine in the magazine well. 
     It is expected that magazine safety mechanisms according to the invention will permit more reliable and safe operation of semiautomatic firearms.