Mar 17, 2026

US12578159 - Firearm trigger mechanism

A trigger mechanism that can be used in AR-pattern firearms has a hammer, a trigger member, a disconnector, a cam, and a “three position” safety selector having safe, standard semi-automatic, and forced reset semi-automatic positions. In the standard semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer and pivoting of the cam from a first position to a second position such that a cam lobe forces the trigger member towards the set position, but prior to reaching the set position the disconnector hook catches the hammer hook, at which time a user must manually release the trigger member to free the hammer from the disconnector to permit the hammer and trigger member to pivot to their set positions so that the user can pull the trigger member to fire the firearm. In the forced reset semi-automatic position, rearward movement of the bolt carrier causes rearward pivoting of the hammer and pivoting of the cam from the first position to the second position such that the cam lobe forces the trigger member to the set position, the safety selector preventing the disconnector hook from catching the hammer hook, at which time the user can pull the trigger member to fire the firearm without manually releasing the trigger member.

Assignee: ABC IP, LLC
Inventors: Brian A Blakley
Filing date: 2024-07-02

firearmtriggermechanismforcedresetfrt

This patent describes a trigger mechanism for AR-pattern firearms that operates in two modes: a standard semi-automatic mode requiring manual release of the trigger and a forced reset semi-automatic mode allowing firing without manual intervention. The mechanism includes a hammer, trigger member, disconnector, and a cam that facilitates the transition between these modes while ensuring safety and functionality.

Claim 1

1 . A firearm trigger mechanism for a firearm having a fire control mechanism pocket and a reciprocating bolt means, the trigger mechanism operable in a first, standard semi-automatic mode and in a second, forced reset semi-automatic mode, the mechanism comprising: a hammer having a hammer sear surface and a hook for engaging a disconnector and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse hammer pivot axis between set and released positions, the hammer adapted to be pivoted rearward by rearward movement of the bolt means, a trigger member having a trigger sear surface and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse trigger member pivot axis between set and released positions, wherein the trigger member sear surface and hammer sear catch surface are in engagement in the set positions of the hammer and trigger member and are out of engagement in the released positions of the hammer and trigger member, the disconnector having a hook for engaging the hammer and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse disconnector pivot axis, and a cam having a cam lobe and adapted to be movably mounted in the fire control mechanism pocket, the cam being movable between a first position and a second position, in the second position the cam lobe forces the trigger member toward the set position, whereupon in the first mode, rearward movement of the bolt means causes rearward pivoting of the hammer such that the disconnector hook catches the hammer hook, and thereafter the bolt means moves forward into battery, at which time a user must manually reduce pressure on the trigger member to free the hammer from the disconnector to permit the hammer and trigger member to pivot to the set positions so that the user can pull the trigger member to fire the firearm, and whereupon in the second mode, rearward movement of the bolt means causes rearward pivoting of the hammer such that the disconnector hook is prevented from holding the hammer, and thereafter the bolt means moves forward into battery, at which time the user can pull the trigger member to fire the firearm. a hammer having a hammer sear surface and a hook for engaging a disconnector and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse hammer pivot axis between set and released positions, the hammer adapted to be pivoted rearward by rearward movement of the bolt means, a trigger member having a trigger sear surface and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse trigger member pivot axis between set and released positions, wherein the trigger member sear surface and hammer sear catch surface are in engagement in the set positions of the hammer and trigger member and are out of engagement in the released positions of the hammer and trigger member, the disconnector having a hook for engaging the hammer and adapted to be mounted in the fire control mechanism pocket to pivot on a transverse disconnector pivot axis, and a cam having a cam lobe and adapted to be movably mounted in the fire control mechanism pocket, the cam being movable between a first position and a second position, in the second position the cam lobe forces the trigger member toward the set position, whereupon in the first mode, rearward movement of the bolt means causes rearward pivoting of the hammer such that the disconnector hook catches the hammer hook, and thereafter the bolt means moves forward into battery, at which time a user must manually reduce pressure on the trigger member to free the hammer from the disconnector to permit the hammer and trigger member to pivot to the set positions so that the user can pull the trigger member to fire the firearm, and whereupon in the second mode, rearward movement of the bolt means causes rearward pivoting of the hammer such that the disconnector hook is prevented from holding the hammer, and thereafter the bolt means moves forward into battery, at which time the user can pull the trigger member to fire the firearm.

Google Patents

https://patents.google.com/patent/US12578159

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12578159