Flap Door Mechanism for Server Fan Gap Reflow Prevention

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The installation of multiple thermal fans in server computers creates gaps when one fan is removed for replacement, allowing airflow into the casing and disrupting heat dissipation, leading to reduced efficiency.

Innovation Solution

A flap door mechanism with a door member, resilient member, and spring arm member that pivots to cover the gap, utilizing torque from deformation to resist airflow and prevent reflow, while also reducing permanent deformation of the resilient member through bending of the spring arm member.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If thermal fans are installed in multiple installing openings for efficient heat dissipation, then heat dissipating efficiency is improved, but when one fan is removed, reflow enters through the gap and disturbs the airflow, reducing heat dissipating efficiency

Engineering Contradiction:

Improveheat dissipating efficiencyVSAvoidreflow

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

A door member is introduced as an intermediary component between the installing opening and the casing interior. The door member can rotate between an opened state (allowing fan installation/removal) and a closed state (sealing the opening to prevent reflow). This mediator resolves the contradiction by dynamically controlling airflow based on operational needs.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The door member transitions from a static barrier to a dynamic component that can rotate between opened and closed positions. The resilient member provides automatic restoration force, enabling the door to dynamically adapt its state based on whether a fan is installed, thus preventing reflow while maintaining ease of fan replacement.

Inventive Principle:

Principle #15Dynamics

2Object-affected harmful factors

If a door member is added to close the gap and prevent reflow, then reflow prevention is improved, but the device complexity increases

Engineering Contradiction:

Improvereflow preventionVSAvoidmechanism complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The resilient member is configured to automatically push the door member to the closed position when a fan is installed, eliminating the need for motors, sensors, or control systems. The mechanism self-regulates based on the physical presence or absence of the fan, maintaining simplicity while achieving effective reflow prevention.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

Complex electronic control systems are replaced with a simple mechanical resilient member that provides automatic door positioning. The resilient member's elastic force substitutes for complex actuation mechanisms, achieving reliable door closure with minimal components.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If the resilient member continuously pushes the door member to rotate, then the door closing function is maintained, but permanent deformation of the resilient member may occur, reducing its lifespan

Engineering Contradiction:

Improvedoor closing functionVSAvoidresilient member lifespan

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The resilient member alternates between deformed and recovered states as the door member rotates back and forth during fan installation and removal. This periodic deformation allows the resilient member to function reliably over time without accumulating permanent deformation, extending its operational lifespan.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The spring arm member provides dynamic compliance by bending during door rotation, allowing the resilient member to deform within elastic limits rather than maintaining constant rigid contact. This dynamic interaction prevents excessive stress accumulation and extends the resilient member's service life.

Inventive Principle:

Principle #15Dynamics

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

Enhances heat dissipating efficiency by preventing airflow into the casing and prolongs the mechanism's life by avoiding permanent deformation of the resilient member.

Implementation Method 1

The resilient member is installed on the door member and for driving the door member to rotate in a first direction

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

The resilient member drives the first end to push the abutting end for bending the spring arm member when the door member rotates in a second direction opposite to the first direction, so as to reduce deformation between the first end and the second end of the resilient member

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Data Source

PatentUS9055675B2Flap door mechanism and electronic device therewith

Publication Date: 2015.06.09 WISTRON CORP

AI summary

A flap door mechanism with closable function includes a door member, a resilient member and a spring arm member. The door member is pivoted to a casing. The resilient member is installed on the door member and for driving the door member to rotate in a first direction. The resilient member includes a first end and a second end. The spring arm member is selectively disposed on the door member or on the casing. The spring arm member abuts against the first end. When the door member rotates in a second direction opposite to the first direction, the spring arm member is pushed to bend by the first end or is pressed to flatten by the casing, so as to reduce deformation between the first end and the second end of the resilient member.