Semi-automatic firearm trigger mechanism and safety device

Abstract

A firearm has a frame, a barrel assembly, a slide assembly which holds a recoil assembly, and a firing system with a trigger assembly and safety mechanism. The slide and recoil assemblies are located above the barrel so that the barrel is situated between the topmost part of the frame and the bottom of the slide assembly. The barrel assembly includes a housing which is covered by the slide assembly and secures one side of the recoil assembly. The barrel can be removably connected to the frame through front and rear mounts with removable pins and can modularly connect with the frame and slide assembly so that different caliber barrels can be interchanged. In addition to the trigger, the trigger assembly has a hammer, a sear, a lever arm that engages the trigger, sear and hammer, and springs that bias the trigger assembly components.

1 - 20 . (canceled) 
     
     
         21 . A firearm for discharging ammunition, comprising:
 a frame comprising a handle;   a barrel assembly connected to the frame;   a hammer pivotally mounted to the frame, wherein the hammer comprises a catch surface and a cam surface;   a hammer spring biasing the hammer to a discharge orientation;   a trigger having a rest position and a pulled position;   a sear comprising a latch on a front end and a tab extending from a side surface, wherein the sear has a latching position with the latch engaging the catch of the hammer and holding the hammer in a cocked orientation, wherein the sear has a releasing position with the latch disengaged from the catch, and wherein the hammer rotates from the cocked orientation to the discharge orientation when the sear moves from the latching position to the releasing position; and   a lever arm connecting the trigger to the sear, the lever arm comprising a ram and an extension, wherein the lever arm has a ready position and a firing position, wherein the ram engages the tab when the lever arm is in the ready position, wherein the cam surface of the hammer engages the extension when the lever arm is in the firing position, and wherein the cam surface forces the ram to disengage from the tab as the hammer rotates from the cocked orientation to the discharge orientation.   
     
     
         22 . The firearm of  claim 21 , further comprising a safety mechanism comprising a safety switch and a shaft extending through the frame proximal to the sear, wherein the safety switch is connected to the shaft and rotates the shaft in the frame between a safety-on position and a safety-off position, wherein the shaft comprises a cutout section, wherein the cutout section is adjacent to a portion of the sear when the shaft is in the safety-off position and wherein the portion of the sear fits within the cutout section in the safety-off position, and wherein the cutout section is rotated away from the sear in the safety-on position. 
     
     
         23 . The firearm of  claim 21 , wherein the barrel assembly comprises a gun barrel, a front mount, a rear mount and a housing, wherein the barrel assembly has a front portion, a rear portion, a top side, and a bottom side, wherein the front mount extends from the bottom side of front portion and connects to the frame, wherein the rear mount extends from the bottom side of the rear portion and connects to the frame, wherein the housing extends from the top side of the gun barrel and has an inner surface and a front surface, wherein the top side is further comprised of a pair of longitudinal ribs extending between the front portion and the rear portion. 
     
     
         24 . The firearm of  claim 23 , further comprising a recoil assembly and a slide assembly, the recoil assembly comprising a rod, a helical spring and a sleeve, wherein the recoil rod comprises a nose portion and an elongated rod extending from the nose portion, wherein the sleeve has a flange around a first open end and an annular rib at a second open end, wherein the elongated rod extends through an interior portion of the sleeve and projects out the second open end, wherein the helical spring surrounds the elongated rod and is contained between the nose portion and the annular rib, wherein an outer surface of the sleeve is contained within the inner surface of the housing, wherein the flange abuts the front surface of the housing, wherein the slide assembly comprises a front casing, an internal recess, a breech plate, a rear casing, a firing pin bore, and a conduit between the internal recess and the rear casing, wherein the front casing extends from the internal recess to a distal end around the nose portion of the recoil rod, wherein the front casing mates with the barrel and encloses the recoil assembly in an interior space between the front casing and the top side of the barrel, wherein the distal end of the front casing is fixedly connected to the nose portion of the recoil assembly, wherein the breech plate has a firing pin hole aligned with the firing pin bore, wherein the front casing is slidably connected to the top side of the barrel, and wherein the rear casing is slidably connected to the frame. 
     
     
         25 . The firearm of  claim 24 , wherein the recoil assembly further comprises a dampener situated between the spring and the nose portion of the recoil rod, and wherein the barrel assembly is located between the slide assembly and the frame. 
     
     
         26 . The firearm of  claim 23 , further comprising a first takedown pin and a second takedown pin, wherein the frame is further comprised of an arm and a pair of sidewalls, wherein the arm extends from the handle and a cavity is recessed from a top face of the arm, wherein the pair of sidewalls is situated between the arm and the handle, wherein the arm has a first pair of apertures extending through the aperture, wherein the pair of sidewalls have a second pair of apertures, wherein the front mount is seated in the cavity and has a front aperture aligned with first pair of apertures, wherein the first takedown pin extends through the front aperture and the first pair of apertures, wherein the rear mount is seated between the pair of sidewalls and has a rear aperture aligned with the second pair of apertures, and wherein the second takedown pin extends through the rear aperture and the second pair of apertures. 
     
     
         27 . The firearm of  claim 21 , further comprising a lever arm spring operatively connected to the lever arm, wherein the lever arm spring biases the lever arm towards the hammer. 
     
     
         28 . The firearm of  claim 27 , further comprising a safety mechanism, wherein the safety mechanism comprises a safety switch, a shaft, and a cam, wherein the shaft connects to the safety switch at a proximal end, extends through the frame proximal to the lever arm, and connects to the cam on an interior side of the frame, wherein the safety mechanism has a first orientation and rotates to a second orientation, wherein the lever arm further comprises a hook, a notch, and a projection, wherein the cam engages the projection in the second orientation and forces the lever to a locked position with the ram disengaged from the tab, with the notch positioned over a firing detent proximate to the interior side of the frame, and with the hook engaged around a safety catch extending from the side surface of the sear. 
     
     
         29 . The firearm of  claim 21 , further comprising a second barrel assembly and at least one insert, wherein the slide has a firing pin hole in a breech plate and a fitting in the breech plate around the pin hole at a location proximate to a chamber section of the barrel assembly, wherein the insert is mounted in the fitting, wherein the insert accommodates a second caliber of ammunition corresponding with the second barrel assembly, and wherein the barrel assembly corresponds with a first caliber of ammunition different from the second caliber. 
     
     
         30 . A firearm for discharging ammunition, comprising:
 a frame comprising a handle;   a barrel assembly connected to the frame;   a hammer pivotally mounted to the frame;   a hammer spring biasing the hammer to a discharge orientation;   a trigger having a rest position and a pulled position;   a sear having a first position and a second position, wherein the sear holds the hammer in a cocked orientation when in the first position, and wherein the sear disengages from holding the hammer in the second position and releases the hammer to its discharge orientation;   a lever arm connecting the trigger to the sear, wherein a movement of the trigger from the rest position to the pulled position moves the sear from its first position to its second position; and   a safety mechanism comprising a safety switch and a shaft extending through the frame proximal to the sear, wherein the safety switch is connected to the shaft and rotates the shaft in the frame between a safety-on position and a safety-off position, wherein the shaft comprises a cutout section, wherein the cutout section is adjacent to a portion of the sear when the shaft is in the safety-off position and wherein the portion of the sear fits within the cutout section in the safety-off position, and wherein the cutout section is rotated away from the sear in the safety-on position.   
     
     
         31 . The firearm of  claim 30 , further comprising a second barrel assembly and at least one insert, wherein the slide has a firing pin hole in a breech plate and a fitting in the breech plate around the pin hole at a location proximate to a chamber section of the barrel assembly, wherein the insert is mounted in the fitting, wherein the insert accommodates a second caliber of ammunition corresponding with the second barrel assembly, and wherein the barrel assembly corresponds with a first caliber of ammunition different from the second caliber. 
     
     
         32 . The firearm of  claim 30 , wherein the hammer comprises a catch surface and a cam surface, wherein the sear comprises a latch on a front end and a tab extending from a side surface, wherein the latch engages the catch of the hammer in the first position to hold the hammer in the cocked orientation, wherein the latch is disengaged from the catch in the second position, and wherein the hammer rotates from the cocked orientation to the discharge orientation when the sear moves from the first position to the second position. 
     
     
         33 . The firearm of  claim 32 , wherein the lever arm further comprises a ram and an extension, wherein the lever arm has a ready position and a firing position, wherein the ram engages the tab when the lever arm is in the ready position, wherein the cam surface of the hammer engages the extension when the lever arm is in the firing position, and wherein the cam surface forces the ram to disengage from the tab as the hammer rotates from the cocked orientation to the discharge orientation. 
     
     
         34 . The firearm of  claim 30 , further comprising a recoil assembly and a slide assembly, wherein the barrel assembly is located between the slide assembly and the frame, and wherein the recoil assembly is located within the slide assembly. 
     
     
         35 . The firearm of  claim 30 , further comprising a recoil assembly and a slide assembly, wherein the recoil assembly further comprises a recoil rod with an elongated rod and a nose portion, a spring situated around the elongated rod, and a dampener situated between the spring and the nose portion of the recoil rod. 
     
     
         36 . A firearm for discharging ammunition, comprising:
 a frame comprising a handle;   a barrel assembly connected to the frame;   a hammer pivotally mounted to the frame, wherein the hammer comprises a catch surface and a cam surface;   a hammer spring biasing the hammer to a discharge orientation;   a trigger having a rest position and a pulled position;   a sear comprising a latch on a front end and a tab extending from a side surface, wherein the sear has a latching position with the latch engaging the catch of the hammer and holding the hammer in a cocked orientation, wherein the sear has a releasing position with the latch disengaged from the catch, and wherein the hammer rotates from the cocked orientation to the discharge orientation when the sear moves from the latching position to the releasing position;   a lever arm connecting the trigger to the sear, the lever arm comprising a ram and an extension, wherein the lever arm has a ready position and a firing position, wherein the ram engages the tab when the lever arm is in the ready position, wherein the cam surface of the hammer engages the extension when the lever arm is in the firing position, and wherein the cam surface forces the ram to disengage from the tab as the hammer rotates from the cocked orientation to the discharge orientation; and   a safety mechanism comprising a safety switch and a shaft extending through the frame proximal to the sear, wherein the safety switch is connected to the shaft and rotates the shaft in the frame between a safety-on position and a safety-off position, wherein the shaft comprises a cutout section, wherein the cutout section is adjacent to a portion of the sear when the shaft is in the safety-off position and wherein the portion of the sear fits within the cutout section in the safety-off position, and wherein the cutout section is rotated away from the sear in the safety-on position.   
     
     
         37 . The firearm of  claim 36 , further comprising a second barrel assembly and at least one insert, wherein the slide has a firing pin hole in a breech plate and a fitting in the breech plate around the pin hole at a location proximate to a chamber section of the barrel assembly, wherein the insert is mounted in the fitting, wherein the insert accommodates a second caliber of ammunition corresponding with the second barrel assembly, and wherein the barrel assembly corresponds with a first caliber of ammunition different from the second caliber. 
     
     
         38 . The firearm of  claim 36 , further comprising a recoil assembly and a slide assembly, wherein the barrel assembly is located between the slide assembly and the frame. 
     
     
         39 . The firearm of  claim 36 , further comprising a recoil assembly and a slide assembly, wherein the recoil assembly further comprises a recoil rod with an elongated rod and a nose portion, a spring situated around the elongated rod, and a dampener situated between the spring and the nose portion of the recoil rod. 
     
     
         40 . The firearm of  claim 30 , further comprising a recoil assembly and a slide assembly, the recoil assembly comprising a rod, a helical spring and a sleeve, wherein the recoil rod comprises a nose portion and an elongated rod extending from the nose portion, wherein the sleeve has a flange around a first open end and an annular rib at a second open end, wherein the elongated rod extends through an interior portion of the sleeve and projects out the second open end, wherein the helical spring surrounds the elongated rod and is contained between the nose portion and the annular rib, wherein an outer surface of the sleeve is contained within the inner surface of the housing, wherein the flange abuts the front surface of the housing, wherein the slide assembly comprises a front casing, an internal recess, a breech plate, a rear casing, a firing pin bore, and a conduit between the internal recess and the rear casing, wherein the front casing extends from the internal recess to a distal end around the nose portion of the recoil rod, wherein the front casing mates with the barrel and encloses the recoil assembly in an interior space between the front casing and the top side of the barrel, wherein the distal end of the front casing is fixedly connected to the nose portion of the recoil assembly, wherein the breech plate has a firing pin hole aligned with the firing pin bore, wherein the front casing is slidably connected to the top side of the barrel, and wherein the rear casing is slidably connected to the frame.