Fire Control Group with User-Selectable Trigger Profiles

Solution Overview

Problem

Firearms typically have either a duty trigger or a rapid fire/precision trigger, neither of which meets the desired characteristics for all usage scenarios, as duty triggers are safe but impede rapid firing, while rapid fire triggers are unsafe for normal shooting.

Innovation Solution

A fire control group with a selector switch that allows users to choose between safe, duty, and rapid fire/precision trigger profiles, utilizing a 2-stage or 1-stage design to adjust trigger pull weight and travel, enabling three modes of operation: safe, 2-stage semiautomatic, and 1-stage semiautomatic, with differential torque and spring rates to achieve desired trigger profiles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a duty trigger design is used with considerable trigger pull weight and travel, then safety is improved by preventing accidental discharge, but rapid firing capability deteriorates

Engineering Contradiction:

ImprovesafetyVSAvoidrapid firing capability

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The trigger system dynamically changes its mechanical characteristics through a selector switch that reconfigures the trigger group between duty and rapid fire modes. The disconnectors and cam surfaces enable the trigger pull weight and travel to be adjusted on-the-fly, transforming a static trigger system into a dynamic one that adapts to different operational requirements.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes key trigger parameters (pull weight, travel distance, stage breakdown) by reconfiguring the mechanical connections between trigger, disconnectors, and cam surfaces. The selector switch activates different disconnector configurations that modify these parameters, allowing the same physical trigger to exhibit different functional characteristics suitable for either duty or rapid fire operations.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If a rapid fire trigger design is used with minimal pull weight and travel, then rapid firing capability is improved, but safety deteriorates by increasing unpredictability

Engineering Contradiction:

Improverapid firing capabilityVSAvoidsafety

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The trigger system dynamically changes its mechanical characteristics through a selector switch that reconfigures the trigger group between duty and rapid fire modes. The disconnectors and cam surfaces enable the trigger pull weight and travel to be adjusted on-the-fly, transforming a static trigger system into a dynamic one that adapts to different operational requirements.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes key trigger parameters (pull weight, travel distance, stage breakdown) by reconfiguring the mechanical connections between trigger, disconnectors, and cam surfaces. The selector switch activates different disconnector configurations that modify these parameters, allowing the same physical trigger to exhibit different functional characteristics suitable for either duty or rapid fire operations.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If a single trigger design is used, then device complexity is reduced, but adaptability deteriorates by inability to meet different usage scenario requirements

Engineering Contradiction:

Improvetrigger design simplicityVSAvoidusage scenario adaptability

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The trigger group is designed as a universal system that can perform multiple functions through a single integrated mechanism. The selector switch, disconnectors, and cam surfaces work together to enable the same physical trigger to provide both duty and rapid fire capabilities, eliminating the need for separate trigger assemblies for different operational modes.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The trigger system dynamically changes its mechanical characteristics through a selector switch that reconfigures the trigger group between duty and rapid fire modes. The disconnectors and cam surfaces enable the trigger pull weight and travel to be adjusted on-the-fly, transforming a static trigger system into a dynamic one that adapts to different operational requirements.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS9989327B2Fire control group with multiple user-selectable trigger profiles

Publication Date: 2018.06.05 HORCH ROBERT ADAM

AI summary

A fire control group is capable of operating in multiple, user-selectable modes. The fire control group includes two disconnectors, a selector switch, and a trigger with a tang. The selector switch has a series of cams which interact with the tang of the trigger and surfaces of the two disconnectors to provide different hammer break points (i.e., distances from neutral), reset distances, overtravel distances, and pull weights, depending on a rotational position of the selector switch. In one embodiment, the fire control group is capable of a safe mode, a 2-stage trigger pull, and a 1-stage trigger pull.