Variable Volume Catapult Inner Tube for Weight-Adaptive Ejection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current high energy catapult assemblies face challenges in accommodating varying occupant weights, as they must generate sufficient force to eject lighter occupants without injuring them and ensure proper aircraft separation velocity for heavier occupants.

Innovation Solution

A high energy catapult assembly with a variable volume inner tube, where the open volume is adjusted based on occupant weight using a controller and actuator, allowing for different distances between sealing interfaces to optimize the ejection force, featuring a propellant cartridge and seal within the inner tube, and a telescoping outer tube.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If the catapult generates high force to eject heavier occupants, then proper aircraft separation velocity is achieved, but lighter occupants may be injured

Engineering Contradiction:

Improveejection forceVSAvoidinjury to lighter occupants

Core Design Contradiction:

ForceVSObject-affected harmful factors

Solution Approach 1:

The patent implements a variable volume inner tube that can dynamically adjust its internal volume based on detected occupant weight. The inner tube transitions between extended and retracted positions, changing the combustion chamber volume to optimize ejection force for different occupant weights, thereby resolving the contradiction between providing sufficient force for heavy occupants and avoiding excessive force for light occupants

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the physical parameter of combustion chamber volume based on occupant weight detection. By adjusting the inner tube position, the system modifies the volume parameter to match the energy requirements of different occupant weights, ensuring safe and effective ejection for all occupants regardless of weight

Inventive Principle:

Principle #35Parameter changes

2Object-affected harmful factors

If the catapult generates low force to protect lighter occupants, then injury is reduced, but heavier occupants may not achieve proper aircraft separation velocity

Engineering Contradiction:

Improveinjury preventionVSAvoidaircraft separation velocity

Core Design Contradiction:

Object-affected harmful factorsVSSpeed

Solution Approach 1:

The variable volume inner tube provides dynamic adaptation to different occupant weights. When a heavier occupant is detected, the inner tube extends to provide maximum volume and corresponding ejection force, ensuring adequate separation velocity while still protecting lighter occupants when the tube is retracted

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system incorporates weight detection feedback to determine the appropriate inner tube position. The detected occupant weight information is used to control the actuator that positions the inner tube, creating a feedback loop that optimizes ejection parameters based on actual occupant characteristics

Inventive Principle:

Principle #23Feedback

3Device complexity

If the inner tube volume is fixed, then the device structure is simple, but it cannot accommodate varying occupant weights effectively

Engineering Contradiction:

Improvecatapult structureVSAvoidaccommodation of varying occupant weights

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent transforms the static fixed-volume inner tube into a dynamic variable-volume component. The inner tube can extend and retract along the catapult assembly, allowing the system to adapt its combustion chamber volume to different occupant weights while maintaining a relatively simple overall structure

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The variable volume inner tube is nested within the outer tube of the catapult assembly. When the inner tube retracts, it nests within the outer tube, minimizing the overall footprint. When extended, it provides the necessary volume increase without requiring a completely separate mechanism

Inventive Principle:

Principle #7Nested doll (Nesting)

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

This solution ensures safer ejection by adjusting the ejection force according to the occupant's weight, providing appropriate acceleration for both lighter and heavier occupants while maintaining proper aircraft separation velocity.

Implementation Method 1

Current high energy catapult assemblies use a gas generator that generates pressure in the catapult and forces the ejection seat and its occupant from the aircraft

Methodology Applied

Scientific EffectCombustion: Combustion

Implementation Method 2

An actuator may be configured to change an open volume of the inner tube chamber... Actuation of the piston may translate the propellant cartridge within the inner tube chamber

Methodology Applied

Scientific EffectMechanical displacement: Displacement

Data Source

PatentUS11479362B1Variable volume high energy catapult assemblies for ejection systems

Publication Date: 2022.10.25 GOODRICH CORP

AI summary

A high energy catapult assembly may comprise an outer tube and an inner tube located within the outer tube. The outer tube may be configured to telescope relative to the inner tube. A propellant cartridge may be located in an inner tube chamber of the inner tube. An actuator may be configured to change an open volume of the inner tube chamber.