Trigger mechanism for a firearm

Abstract

Embodiments of the present disclosure relate to trigger mechanisms for firearms. In one aspect of the present disclosure, the trigger mechanism can include a linkage between a striker sear and a main sear to control an amount of force exerted on the main sear by the striker sear. A portion of the force exerted on the striker sear by the striker can be exerted on the main sear through the sear linkage. In another aspect of the present disclosure, trigger mechanisms are described which additionally, or alternatively utilize one or more biasing members to provide a variable trigger pull weight.

What is claimed is: 
     
         1 . A trigger mechanism, comprising:
 a housing;   a first sear;   a second sear coupled to the first sear, the second sear being rotatable relative to the housing;   a third sear rotatably coupled to the housing, the third sear forming a surface that engages with a distal end of the second sear to prevent rotation of the second sear; and   a trigger configured to disengage the surface of the third sear from the distal end of the second sear when the trigger is rotated.   
     
     
         2 . The trigger mechanism of  claim 1 , further comprising a sear linkage coupling the first sear to the second sear, wherein:
 the sear linkage is rotatably coupled to the first sear by a first pin;   the second sear is rotatable relative to the housing about an axis; and   the sear linkage is rotatably coupled to the second sear by a second pin, the second pin being laterally offset from the axis.   
     
     
         3 . The trigger mechanism of  claim 1 , wherein the surface of the third sear translates relative to the distal end of the second sear a distance before disengaging from the distal end of the second sear. 
     
     
         4 . The trigger mechanism of  claim 2 , wherein:
 the first sear comprises a distal end and a proximal end;   the sear linkage is coupled to the distal end of the first sear; and   the first sear is rotatably coupled to the housing at the proximal end of the first sear.   
     
     
         5 . The trigger mechanism of  claim 1 , wherein the first sear is configured to retain a striker in a biased state while the surface of the third sear is engaged with the distal end of the second sear. 
     
     
         6 . The trigger mechanism of  claim 1 , wherein the third sear is biased to retain engagement between the surface of the third sear and the distal end of the second sear. 
     
     
         7 . The trigger mechanism of  claim 1 , further comprising a spring contacting the second sear, the spring biasing the second sear to rotate about a pin coupling the second sear to the housing. 
     
     
         8 . A firearm comprising:
 a stock;   a barrel;   a receiver configured to couple to the stock and the barrel;   a bolt assembly including a firing pin;   a trigger mechanism disposed at least partially within the receiver, the trigger mechanism comprising:
 a housing; 
 a striker sear; 
 a main sear coupled to the striker sear and rotatably coupled to the housing; 
 a trigger sear rotatably coupled to the housing, the trigger sear engaging with the main sear to prevent rotation of the main sear; and 
 a trigger; 
   wherein the trigger sear disengages from the main sear to permit rotation of the main sear when the trigger is rotated.   
     
     
         9 . The firearm of  claim 8 , wherein:
 the firing pin is biased to move toward the barrel;   the striker sear prevents the firing pin from moving toward the barrel; and   the firing pin exerts a force on the striker sear.   
     
     
         10 . The firearm of  claim 9 , wherein the trigger mechanism further comprises a sear linkage coupled to the striker sear and the main sear, the force exerted on the striker sear at least partially transferring to the main sear through the sear linkage. 
     
     
         11 . The firearm of  claim 10 , wherein the force exerted on the striker sear is at least partially applied on the main sear through the sear linkage. 
     
     
         12 . The firearm of  claim 10 , wherein:
 the main sear engages the trigger sear at a first end of the main sear; and   the sear linkage is coupled to the main sear at a second end of the main sear.   
     
     
         13 . The firearm of  claim 8 , wherein the trigger sear is biased to engage the main sear. 
     
     
         14 . The firearm of  claim 9 , wherein the trigger mechanism further comprises a locking member, the locking member enabling the firing pin to move toward the barrel while the locking member is in a first position the locking member limiting the firing pin from moving toward the barrel while the locking member is in a second position. 
     
     
         15 . A trigger mechanism, comprising:
 a housing;   a sear rotatably coupled to the housing;   an actuator rotatably coupled to the housing, the actuator engaging with the sear to prevent rotation of the sear;   a trigger configured to disengage the actuator from the sear when the trigger is rotated;   a first biasing member and a second biasing member, the first biasing member and the second biasing member configured to bias the actuator and the sear to engage one another.   
     
     
         16 . The trigger mechanism of  claim 15 , wherein the first biasing member and the second biasing member are adjustable to vary a force required to rotate the trigger and disengage the actuator from the sear. 
     
     
         17 . The trigger mechanism of  claim 16 , wherein:
 an amount of force exerted on the actuator from the first biasing member is adjustable by rotating a first fastener at least partially disposed within the housing; and   an amount of force exerted on the actuator from the second biasing member is adjustable by rotating a second fastener at least partially disposed within the housing.   
     
     
         18 . The trigger mechanism of  claim 15 , wherein a force applied to the actuator by the first biasing member is different from a force applied to the actuator by the second biasing member. 
     
     
         19 . The trigger mechanism of  claim 15 , wherein the first biasing member and the second biasing member comprise coil springs. 
     
     
         20 . The trigger mechanism of  claim 19 , wherein:
 the housing forms a first aperture and the first biasing member is at least partially disposed within the first aperture;   the housing forms a second aperture and the second biasing member is at least partially disposed within the second aperture;   at least one of the first biasing member or the second biasing member is retained within the housing between a fastener and the actuator; and   the fastener forms a tamper proof interface.