Compound Shell Casing Weight Reduction Composite Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ammunition cartridges made with brass shell casings are heavy and expensive, posing challenges for weight reduction and cost-effectiveness while maintaining safe and reliable operation.
Innovation Solution
A compound shell casing design comprising a lightweight outer member, typically made of aluminum, and a stronger inner member, often made of stainless steel, which are assembled to form a tubular structure with a friction fit or bonding, allowing for reduced weight and cost without compromising performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If brass is used for shell casing, then structural integrity and ease of manufacture are improved, but weight and cost increase
Solution Approach 1:
The patent applies composite materials by combining an outer shell made of lightweight material (aluminum or polymer) with an inner liner made of strong material (brass or steel). This composite structure achieves both weight reduction and maintained structural integrity, resolving the contradiction between using heavy strong materials and reducing weight.
Solution Approach 2:
The shell casing is segmented into two distinct components: an outer shell and an inner liner. Each component performs its specialized function - the outer shell provides weight reduction and cost savings, while the inner liner provides structural integrity and performance. This segmentation allows optimization of each part for its specific purpose.
2Reliability
If brass is used for shell casing, then manufacturing reliability is improved, but cost increases
Solution Approach 1:
The composite structure allows the outer shell to be made from cost-effective materials like aluminum or polymer, while the critical inner liner uses traditional reliable materials like brass or steel. This division reduces overall material cost while maintaining manufacturing reliability in the critical components.
Solution Approach 2:
Different materials are applied to different parts of the shell casing based on functional requirements. The outer shell uses economical materials where weight and cost are priorities, while the inner liner uses proven reliable materials where performance and manufacturing reliability are critical. This local differentiation optimizes both cost and reliability.
3Weight of moving object
If lightweight materials are used for shell casing, then weight is reduced, but structural integrity and ease of manufacture deteriorate
Solution Approach 1:
The patent uses composite materials where the outer shell is made of lightweight material (aluminum or polymer) and the inner liner is made of strong material (brass or steel). This combination achieves weight reduction from the outer shell while the inner liner maintains structural integrity, resolving the contradiction between lightweight and strong.
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 compound shell casing achieves a weight reduction of 12-60% compared to conventional brass casings, enhancing operational safety and reducing manufacturing costs while maintaining structural integrity and reliability.
Implementation Method 1
The inner member has a circumferentially extending downwardly and rearwardly facing face on its exterior that engages the seat in the central passage of the outer member
Data Source
AI summary
A compound shell casing comprising:a generally tubular outer member having an open forward end, an open rearward end, and a central passage extending therebetween, with a circumferentially extending, forwardly and inwardly facing seat in the rearward portion of the central passage;an inner member disposed in the rearward end of the central passageway of the outer member, the inner member comprising a first forwardly facing cup-shaped portion, and a second, rearwardly facing cup-shaped portion opening to the open rearward end of the outer member, and a circumferentially extending downwardly and rearwardly facing shoulder on the exterior of inner member engaging the seat in the central passage of the outer member.