Tubular Energy Absorber With Buffer-Cutting Impact Stages

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing impact absorbers face limitations in effectively absorbing impacts beyond a certain level, leading to unexpected destruction and limited durability across various impact magnitudes.

Innovation Solution

A tubular energy absorber with a buffer unit that reversibly absorbs impacts within a predetermined range and includes a cutting mechanism to continue absorbing impacts beyond this range, utilizing a stepped portion for additional absorption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If cutting is performed at the same time as impact is provided, then impact absorption is achieved, but the structure becomes irreversible and cannot absorb additional impact

Engineering Contradiction:
Improveimpact absorption capabilityVSAvoidrepeated impact absorption
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The energy absorption process is segmented into two distinct stages: a reversible buffer stage for initial impacts and an irreversible cutting stage for excessive impacts. The buffer unit and cutting unit are functionally separated, allowing the system to handle multiple impact scenarios effectively.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system dynamically transitions between two operational modes based on impact magnitude. For normal impacts, the buffer unit operates reversibly. When impact exceeds the buffer capacity, the system automatically engages the cutting unit for irreversible energy absorption, enabling adaptive response to varying impact conditions.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If a buffer unit is used to reversibly absorb impact, then repeated impact absorption is enabled, but impacts exceeding the buffer range cannot be absorbed

Engineering Contradiction:
Improverepeated impact absorptionVSAvoidprotection against excessive impact
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The buffer unit serves as a preliminary cushioning mechanism that activates first to absorb minor impacts reversibly. This prior cushioning protects the structure from small disturbances while preparing the system for potential larger impacts by consuming energy before the cutting mechanism is engaged.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The buffer unit acts as an intermediary between the collision unit and the cutting unit. It mediates the impact energy transmission, filtering out minor impacts that don't require structural cutting while allowing excessive impacts to pass through to trigger the cutting mechanism.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If cutting stroke is minimized for efficient energy absorption, then impact absorption effectiveness is improved, but the cutting mechanism requires precise positioning

Engineering Contradiction:
Improveimpact absorption effectivenessVSAvoidcutting unit positioning
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The cutting unit is pre-positioned and pre-aligned with the external unit during assembly. This preliminary positioning ensures that when impact occurs, the cutting edges are already in the correct configuration to engage with minimal stroke, eliminating the need for complex real-time positioning mechanisms.

Inventive Principle:
Principle #10Preliminary action

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 absorber achieves stable and durable impact absorption by reversibly absorbing impacts within a set range and irreversibly absorbing excess impacts through cutting, minimizing the cutting stroke and enhancing durability.

Implementation Method 1

the buffer part may be reversibly restored to an original state, when the impact within a predetermined range is applied

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

The external unit cuts or performs cutting and absorbs the external impact, as the collision unit moves

Methodology Applied
Scientific EffectFracture Mechanics: Fracture Mechanics

Data Source

PatentEP4663972A1Tubular energy absorber having buffer unit
Publication Date: 2025.12.17 KOREA RAILROAD RESEARCH INSTITUTE
  • EP4663972A1 patent drawingFigure 1
  • EP4663972A1 patent drawingFigure 2
  • EP4663972A1 patent drawingFigure 3

AI summary

An energy absorber includes an external unit, a collision unit and a buffer unit. The external unit extends with forming a stepped portion, and forms a predetermined inner space. The collision unit extends from the inner space to outside, and moves toward the inner space due to an external impact. The buffer unit is disposed in the inner space, and is connected to the collision unit to absorb the external impact. The external unit cuts or performs cutting and absorbs the external impact, as the collision unit moves.