Fuel Cell Mounting Structure with Rotatable and Breakaway Joining Portions

Solution Overview

Problem

Conventional fuel cell mounting structures are inadequate for mitigating load input during vehicle collisions without causing the fuel cell to break away from the vehicle, which is prohibited by regulations.

Innovation Solution

A fuel cell mounting structure featuring rotatable and breakaway components, where weak portions or anchor portions are designed to fail under load, allowing the fuel cell to rotate within the vehicle body, thereby absorbing collision energy without dislodging from the vehicle.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the fuel cell is securely fixed to prevent breakaway during collision, then the fuel cell remains attached to the vehicle, but the load input to the fuel cell during collision cannot be mitigated

Engineering Contradiction:

Improvefuel cell attachment reliabilityVSAvoidfuel cell load resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The mounting structure is divided into multiple independent joining portions (front side joining portions and rear side joining portions) that can fail independently. Each joining portion has separate weak portions that can break under collision load, allowing progressive failure rather than complete attachment loss or complete load transmission to the fuel cell.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Weak portions are deliberately designed into the joining portions at locations that will fail first under collision load. These pre-designed weak points act as sacrificial elements that absorb collision energy through controlled breaking, protecting the fuel cell from direct load impact while maintaining attachment through remaining intact joining portions.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Strength

If weak portions are designed to break during collision to mitigate load, then the fuel cell is protected from load, but the fuel cell may break away from the vehicle

Engineering Contradiction:

Improvefuel cell load resistanceVSAvoidfuel cell attachment reliability

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

Different regions of the joining portions have different structural qualities - weak portions are designed with reduced thickness or strength at specific locations, while other portions maintain full strength. This local differentiation allows controlled failure at weak portions while maintaining attachment integrity through stronger regions, preventing complete breakaway.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The mounting structure transitions from a static rigid connection to a dynamic system with controlled degrees of freedom. When weak portions break, the fuel cell mounting structure dynamically adjusts its configuration, allowing rotation or displacement that absorbs collision energy while maintaining connection through remaining intact anchor portions or joining portions.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If conventional engine mount structures with breakaway weak portions are used for fuel cell, then the structure is simple and proven, but it causes the fuel cell to break away during collision which is prohibited by regulations

Engineering Contradiction:

Improvemounting structure complexityVSAvoidfuel cell attachment reliability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The mounting structure is divided into multiple independent joining portions (front side joining portions and rear side joining portions) that can fail independently. Each joining portion has separate weak portions that can break under collision load, allowing progressive failure rather than complete attachment loss or complete load transmission to the fuel cell.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Weak portions are deliberately designed into the joining portions at locations that will fail first under collision load. These pre-designed weak points act as sacrificial elements that absorb collision energy through controlled breaking, protecting the fuel cell from direct load impact while maintaining attachment through remaining intact joining portions.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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

Effectively mitigates load input to the fuel cell during collisions without causing it to break away from the vehicle, reducing the risk of damage and maintaining vehicle stability, while also reducing manufacturing costs and weight.

Implementation Method 1

weak portions breaking at a time when load is inputted to the fuel cell from a vehicle body longitudinal direction

Methodology Applied

Scientific EffectFracture Mechanics: Fracture Mechanics

Implementation Method 2

one of the front side joining portions and the rear side joining portions are supported so as to be rotatable with a vehicle transverse direction being an axis of rotation

Methodology Applied

Scientific EffectMechanical Rotation:

Implementation Method 3

a pair of left and right vibration-proofing members that are provided due to front side joining portions and rear side joining portions being mounted to suspension members

Methodology Applied

Scientific EffectVibration Damping: Damping

Data Source

PatentUS10518620B2Fuel cell mounting structure

Publication Date: 2019.12.31 TOYOTA JIDOSHA KK

AI summary

There is provided a fuel cell mounting structure including: a pair of left and right vibration-proofing members that are provided due to front side joining portions and rear side joining portions being mounted to suspension members; and a fuel cell that is supported at least by the pair of left and right vibration-proofing members, and is disposed at vehicle body upper sides of the suspension members, wherein one of the front side joining portions and the rear side joining portions are supported so as to be rotatable with a vehicle transverse direction being an axis of rotation, and another of the front side joining portions and the rear side joining portions are structured so as to break away from the suspension members, due to weak portions breaking at a time when load is inputted to the fuel cell from a vehicle body longitudinal direction.