Open Chamber Ammunition with Triangular Cartridge and Cam Index Drive
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Solution Overview
Problem
Open chamber firearms face issues with jamming, stress distribution, and leakage due to asymmetrical cartridges, and they are not suitable for use in various environmental conditions, while also requiring high power to operate the cylinder rotation.
Innovation Solution
An expandable insert made of high-strength steel is used to distribute stress evenly and accommodate symmetrical triangular rounds, and a cam index drive is implemented to reduce power requirements and enhance performance, along with a sealed cartridge casing to prevent leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If asymmetrical cartridges are used in open chamber firearms, then the cartridges can be inserted from the side of the cylinder, but jamming occurs and stress is concentrated on the cylinder base
Solution Approach 1:
The cartridge case is designed with asymmetrical geometry where one end is rounded to match the curvature of the frame and the other end is flat to match the U-shaped chamber. This asymmetry enables reliable side loading while preventing jamming by ensuring proper orientation and fit within the open chamber mechanism.
2Ease of operation
If asymmetrical cartridges are used in open chamber firearms, then side loading is enabled, but stress is concentrated on the cylinder base material
Solution Approach 1:
The cartridge case employs different geometries at different locations: a rounded end with curved surface to contact the frame and distribute stress, and a flat end to contact the chamber base. This local variation in geometry optimizes stress distribution across different contact points, preventing stress concentration on the cylinder base material.
3Ease of manufacture
If plastic cartridge case assembled in multiple pieces is used, then manufacturing is simplified, but gas leakage occurs at joints
Solution Approach 1:
A flexible sealing element is incorporated at the joint between cartridge case pieces to prevent gas leakage. The sealing element compensates for manufacturing tolerances and maintains gas tightness while allowing the modular construction benefits for ease of manufacture and assembly.
4Ease of operation
If traditional open chamber mechanism is used, then side loading is possible, but high power is required to rotate the cylinder
Solution Approach 1:
A cam mechanism is introduced to dynamically assist the cylinder rotation. The cam converts rotational motion into a dwell position during firing, reducing the power required to rotate the cylinder by utilizing mechanical advantage and timing the rotation to minimize resistance during high-pressure periods.
Data Source
AI summary
Aspects described herein relate to an ammunition round for an open chamber gun mechanism is provided, the round comprising a housing having a triangular shaped cross section and a central longitudinal axis, the housing including at least one projectile positioned along the central longitudinal axis, a propellant positioned behind the at least one projectile along the central longitudinal axis, a first sealed end located at a first end of the housing nearest the propellant, and a second sealed end positioned at a second end of the housing in front of the projectile, wherein the second sealed end is configured to become unsealed after firing of the projectile.