Obviousness

The primary reference for the forced reset trigger mechanism with a locking bar is US10514223B1. The patent US11346627 explicitly states this and highlights that US10514223B1's locking bar is pivotally mounted. The key difference in US11346627 is the slidably mounted locking bar.

Analysis of Obviousness for US Patent 11,346,627 under 35 U.S.C. § 103

The present invention, US Patent 11,346,627, introduces a forced reset semiautomatic trigger mechanism with a sliding blocking bar. The patent acknowledges US Pat. No. 10,514,223 (hereinafter "US '223") as prior art for a "forced reset semiautomatic trigger assembly" with a locking bar that is pivotally mounted. The central distinguishing feature of US '627 is the change in motion of the locking bar from pivotal to linear, sliding movement, offering advantages in adjustability and compensating for tolerance stacking (Description).

A person having ordinary skill in the art (PHOSITA) in firearm trigger mechanisms would have recognized the advantages of a sliding motion over a pivoting motion in certain mechanical contexts, particularly when precision, stability, and adjustability are desired to mitigate issues like "tolerance stacking" and "imprecise actuation contact" (Description).

Combination 1: US Pat. No. 10,514,223 in view of general mechanical engineering principles and existing firearm safety/locking mechanisms.

• US Pat. No. 10,514,223 (Wolf Tactical LLC): This patent teaches a firearm trigger mechanism comprising:

  • A hammer having a sear notch and mounted to pivot on a transverse axis.
  • A trigger member having a sear and mounted to pivot on a transverse axis, with a surface positioned to be forcibly contacted by the hammer when the bolt carrier cycles, thereby forcing the trigger member to the set position. (This constitutes the "forced reset" feature).
  • A locking bar that is pivotally mounted in a frame and spring biased to a first position where it mechanically blocks the trigger member from moving to the released position. This locking bar is movable against the spring bias to a second position when contacted by the bolt carrier reaching a substantially in-battery position, allowing the trigger member to be moved to the released position.

  Thus, US '223 discloses all elements of independent Claim 1 and Claim 6 of US '627, except for the "slidably mounted" aspect of the locking bar.

• Motivation to Modify to a Sliding Locking Bar: The '627 patent itself provides a clear motivation for a PHOSITA to change the pivotal locking bar to a sliding one: "tolerance stacking in the various parts other than the trigger assembly can sometimes result in imprecise actuation contact between the bolt carrier and the locking bar" (Description). The patent states that the sliding movement "also allows for adjustable configurations... which can help compensate for the tolerance stacking effects previously described" (Description). A PHOSITA would recognize that linear guides and sliding mechanisms often offer greater stability, reduced play, and easier adjustability compared to pivoting mechanisms, especially in applications where precise engagement and disengagement with a reciprocating component (like a bolt carrier) are critical. The 1911 pistol, for example, is known to have a sliding trigger which moves straight to the rear, as opposed to a pivoting trigger, which contributes to a predictable trigger press. This demonstrates that sliding components in firearm trigger mechanisms are a known design choice. Further, adjustable sliding mechanisms are widely known in various mechanical arts for compensating for manufacturing tolerances and achieving precise positioning, as seen in general adjustable security bars for sliding doors.

• Obviousness of Claim 1: Given US '223 as a primary reference, a PHOSITA, motivated by the desire to improve the precision and adjustability of the locking bar's interaction with the bolt carrier to mitigate tolerance stacking, would have found it obvious to replace the pivoting locking bar of US '223 with a sliding locking bar. This modification leverages well-known engineering principles where linear movement can provide more controlled and adjustable engagement than pivotal movement. The concept of using a sliding element for blocking or safety in a firearm is also generally known, as evidenced by "sliding lever safety" mechanisms.

Combination 2: Obviousness of Claim 6 (Housing)

Independent Claim 6 introduces the additional element of a "housing" in which the components (hammer, trigger member, and sliding locking bar) are mounted, effectively describing a "drop-in" trigger assembly.

• Prior Art for Drop-in Housings: The concept of "drop-in" trigger assemblies, where the entire trigger mechanism is pre-assembled within a housing for modularity and ease of installation into a firearm receiver, is well-established in the art, particularly for AR-pattern firearms. Numerous products and patents demonstrate this, such as AR15 drop-in triggers from Arrowhead Survival, Midwest Industries, and TriggerTech. These products highlight the advantages of a self-contained design for quick installation and consistent performance without the need for fine-tuning. US Pat. No. 6,722,072 (McCormick) explicitly describes a "trigger group module for firearms and method for installing a trigger group in a firearm."

• Obviousness of Claim 6: If the sliding locking bar of Claim 1 is considered obvious, then integrating this improved mechanism into a drop-in housing, as claimed in Claim 6, would also have been obvious to a PHOSITA. The firearm industry, especially for AR-pattern firearms, routinely utilizes drop-in trigger modules for manufacturing efficiency, ease of assembly, and user convenience. A PHOSITA, seeking to commercialize or implement the improved sliding locking bar trigger, would naturally consider packaging it in a modular, drop-in housing, which is a common and known design choice for such components in AR-style firearms. This would be a mere design choice or an obvious application of known technology to a known device to improve its ease of installation and modularity.

Therefore, the combination of US Pat. No. 10,514,223 with general mechanical engineering principles regarding the advantages of sliding mechanisms for precision and adjustability, or with other firearm-related sliding blocking mechanisms, would render Claim 1 obvious. Further, the combination of this modified trigger mechanism with the well-known practice of using drop-in housings for firearm trigger assemblies (e.g., as exemplified by AR-pattern drop-in triggers), would render Claim 6 obvious.