Vehicle Grab Handle Impact Energy Absorption

Solution Overview

Problem

Traditional grab handles are rigidly attached to vehicle structural members, preventing any relative movement during impacts, which limits their ability to absorb impact energy.

Innovation Solution

A grab handle design featuring a mounting fastener with a selective sliding movement arrangement, utilizing an elongated slot and a locator pin that shears off upon impact, allowing the handle to move relative to the vehicle structural member and absorb energy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the grab handle is rigidly attached to the vehicle structural member, then the mounting strength is improved, but the impact energy absorption capability deteriorates

Engineering Contradiction:

Improvemounting strengthVSAvoidimpact energy absorption

Core Design Contradiction:

StrengthVSLoss of energy

Solution Approach 1:

The mounting system transitions from a static rigid connection to a dynamic system that allows controlled movement. The fastener includes a movable component that can slide within a mounting slot during impact, enabling the handle to move relative to the vehicle structure and absorb impact energy through controlled deformation and friction.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

An intermediary sliding mechanism is introduced between the handle and the vehicle structural member. This intermediary component (the movable fastener element sliding in the mounting slot) mediates the connection, allowing both rigid mounting under normal conditions and controlled movement during impact to absorb energy.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Stability of the object's composition

If the grab handle is rigidly attached to the vehicle structural member, then the positional stability is improved, but the impact resistance deteriorates

Engineering Contradiction:

Improvepositional stabilityVSAvoidimpact resistance

Core Design Contradiction:

Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The mounting system transitions from a static rigid connection to a dynamic system that allows controlled movement. The fastener includes a movable component that can slide within a mounting slot during impact, enabling the handle to move relative to the vehicle structure and absorb impact energy through controlled deformation and friction.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The mounting design incorporates predetermined movement paths and friction characteristics that provide cushioning before full impact occurs. The sliding mechanism is designed to engage and provide resistance progressively, cushioning the impact before it reaches the vehicle structure.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Loss of energy

If a selective sliding movement arrangement is implemented, then the impact energy absorption is improved, but the mounting complexity increases

Engineering Contradiction:

Improveimpact energy absorptionVSAvoidmounting complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The mounting fastener is segmented into distinct functional components: a fixed portion attached to the vehicle structure, a movable portion that slides within the mounting slot, and a retention mechanism. This segmentation allows each component to perform its specific function while maintaining overall system simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system utilizes changes in friction parameters and movement constraints to achieve impact energy absorption. The sliding mechanism is designed with specific friction characteristics that provide resistance during normal use but allow controlled movement during impact, adjusting the effective stiffness of the mounting based on loading conditions.

Inventive Principle:

Principle #35Parameter changes

4Strength

If the grab handle is rigidly attached to the vehicle structural member, then the structural integrity is improved, but the safety during impact deteriorates

Engineering Contradiction:

Improvestructural integrityVSAvoidsafety during impact

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

An intermediary sliding mechanism is introduced between the handle and the vehicle structural member. This intermediary component (the movable fastener element sliding in the mounting slot) mediates the connection, allowing both rigid mounting under normal conditions and controlled movement during impact to absorb energy.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The design converts the harmful rigid connection that transmits impact forces directly to the vehicle structure into a beneficial controlled movement system. The sliding mechanism transforms the harmful impact energy into useful frictional heating and controlled deformation, protecting both the structure and passengers.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 design enables the grab handle to move during impacts, effectively absorbing energy and providing improved safety and comfort for passengers.

Implementation Method 1

a locator pin that shears off upon impact, allowing the handle to move relative to the vehicle structural member

Methodology Applied

Scientific EffectShear stress: Shear Stress

Data Source

PatentUS7407209B2Vehicle grab handle

Publication Date: 2008.08.05 NISSAN MOTOR CO LTD

AI summary

An interior handle assembly includes a vehicle structural member, a handle and a mounting fastener. The handle has a grip portion and a first base mounting portion. The mounting fastener extends between the first base mounting portion and the vehicle structural member fixedly attaching the handle to the vehicle structural member. One of the handle and the vehicle structural member has a selective sliding movement arrangement to provide relative movement of the handle during an impact.