Firearm Breech Locking Member Prevents Unintentional Opening
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Solution Overview
Problem
Existing breech designs for straight-pull bolt-action rifles are prone to unintentional opening, posing safety risks due to complex structures and potential malfunctions, particularly when forces act in the axial direction, which can lead to mechanical damage and injuries.
Innovation Solution
A breech design featuring a locking member that partially penetrates the bolt handle, incorporating a fourth pivot bearing and a resiliently mounted pin, along with a spiral spring, ensures secure engagement and prevents unintentional opening by requiring conscious actuation, while minimizing components and simplifying the structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a chain link is articulated on the locking rod with an offset arrangement, then the bolt handle can be actuated, but the articulated connection can unintentionally open the bolt handle if a force acts in the axial direction
Solution Approach 1:
The patent applies preliminary anti-action by positioning the chain link joint above the dead center position (offset in axial direction from the locking rod axis). This creates a geometric configuration where the chain link forms an angle with the longitudinal axis, generating a counteracting moment that prevents axial forces from unintentionally opening the bolt handle. The offset arrangement ensures that any axial force produces a closing moment rather than an opening moment.
Solution Approach 2:
The patent employs asymmetry by deliberately offsetting the chain link articulation point from the longitudinal axis of the locking rod. This asymmetric positioning creates a non-symmetric geometric relationship between the chain link, bolt handle, and locking rod, which is essential for generating the preventive moment against unintentional opening while maintaining operational functionality.
2Reliability
If multiple elements such as spring-loaded wedges and locking lugs are added to prevent unintentional opening, then safety is improved, but the breech structure becomes complicated
Solution Approach 1:
The patent merges the safety function into the existing chain link mechanism by utilizing the geometric configuration of the articulated connection. Instead of adding separate safety elements, the invention combines the operational function of the chain link with the safety function through clever positioning, thereby preventing unintentional opening without increasing structural complexity.
Solution Approach 2:
The patent changes the geometric parameters of the chain link articulation, specifically positioning it above the dead center position and offset from the locking rod axis. This parameter change transforms the chain link from a simple connection element into a safety-providing mechanism, eliminating the need for additional components while maintaining or enhancing reliability.
3Device complexity
If the chain link is positioned directly above the longitudinal axis at dead center, then the structure is simplified, but unintentional opening can occur due to axial forces
Solution Approach 1:
The patent applies preliminary anti-action by deliberately avoiding the dead center position and instead positioning the chain link joint above it. This creates a preemptive geometric configuration that generates a counteracting moment before any axial force can cause unintentional opening, thus preventing the hazard before it can manifest.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design effectively prevents unintentional breech opening during firing and ensures secure closure, reducing the risk of accidents and malfunctions by requiring deliberate action to open or close the breech, thus enhancing user safety.
Implementation Method 1
a spiral spring, ensures secure engagement and prevents unintentional opening by requiring conscious actuation
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
1. A bolt (1) for a firearm, in particular a straight-pull repeating rifle, comprising a bolt box and a bolt sleeve (3) guided therein, and a locking bar (4) guided in the bolt box and the bolt sleeve (3), which locking bar (4) connects a bolt head facing a cartridge chamber to a bolt handle (5) by means of an interposed straight chain link (6), wherein the chain link (6) is pivotally connected to the bolt handle (5) in a lateral recess (9) of the same covering at least one third of a circle and to the locking bar (4), and the bolt handle (5) is pivotable between an open and a closed position, characterized in that a locking element (14) encompassing a pivot bearing (10) at least partially penetrating the bolt handle (5) is pivotably arranged in relation to the free end of the locking bar (4) arranged inside the bolt (1).