LED Module Fixation Device Resilient Mounting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing LED module mounting systems using screw connections face issues such as torque-related stress cracking, loose screws in vibrating applications, and inadequate thermal interfaces due to high peak forces, leading to reduced reliability and lifetime, especially in outdoor applications.

Innovation Solution

A fixation device with a main body, a first fixation means for securing the LED module to a mounting surface, and at least one resilient portion that applies a controlled force to the LED module, minimizing air gaps and thermal interface material displacement, while allowing for thermal expansion and reducing stress on the plastic housing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If screw connections are used to fixate the LED module to the mounting surface, then the LED module is securely mounted, but stress cracking occurs in the plastic housing and screws become loose in vibrating applications

Engineering Contradiction:
Improvemounting reliabilityVSAvoidhousing strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The fixation system is divided into two independent functions: screws provide anchoring to the mounting surface, while resilient portions provide controlled pressing force to the LED module. This segmentation allows each component to perform its optimal function without compromising the other.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The resilient portions act as intermediaries between the screw fixation and the LED module. They transmit the anchoring force while providing stress relief and controlled pressing force, preventing direct transmission of high peak forces to the plastic housing.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Temperature

If high pressing force is applied through screws to ensure good thermal connection, then thermal contact is improved, but air gaps form and the mounting surface bends

Engineering Contradiction:
Improvethermal connection qualityVSAvoidmounting surface flatness
Core Design Contradiction:
TemperatureVSShape

Solution Approach 1:

The resilient portions are positioned at specific locations on the LED module to apply localized pressing forces exactly where thermal contact is needed. This distributes the thermal interface pressure evenly without concentrating high peak forces that would cause bending.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The resilient portions provide a controlled, reproducible pressing force with optimized magnitude and distribution. This changes the force parameter from high peak forces (screws) to optimized distributed forces, achieving good thermal contact without exceeding the mounting surface's load capacity.

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If precise torque control is implemented for screw mounting, then mounting precision is improved, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improvetorque control precisionVSAvoidmounting system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The resilient portions automatically provide the optimal pressing force through their elastic properties, eliminating the need for precise torque control during assembly. The system self-regulates the force application, simplifying the mounting process and reducing manufacturing complexity.

Inventive Principle:
Principle #25Self-service

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 solution enhances thermal performance, increases reliability, and extends the lifetime of LED modules by providing a defined, reproducible force and minimizing thermal stresses, without requiring precise torque control and reducing the risk of material failure.

Implementation Method 1

at least one resilient portion arranged to extend from the main body and to, in a mounted position, at least partly bear against a predetermined bearing surface of the LED module such that a controlled force which is independent of the first fixation means is applied to the bearing surface of the LED module by means of the resilient portion

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

a thermal interface material 7 is applied between the base plate 4 and the mounting surface 2 to avoid any air-gaps between the mounting surface and the LED module in order to get a lower and better defined thermal resistance

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

by heating up (LED module 1 is switched on) and cooling down (LED module 1 is switched off) the different parts of the LED module 1 will move compared to each other because of their different thermal expansion behavior

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP2721343B1A fixation device and an assembly structure
Publication Date: 2019.11.06 SIGNIFY HOLDING BV
  • EP2721343B1 patent drawingFigure 1a~1b
  • EP2721343B1 patent drawingFigure 2a~2b
  • EP2721343B1 patent drawingFigure 2c~2d

AI summary

There is provided a fixation device (100) and an assembly structure 10 comprising light emitting diode module, LED module, (200) and at least one fixation device (100) for in a mounted position fixating the LED module to a mounting surface (300). The fixation device comprises a main body (103), a first fixation means (102) for securing LED module to the mounting surface, a second fixation means (106, 506) for securing the fixation device to the LED module and at least one resilient portion (107, 108) arranged to extend from the main body and to, in a mounted position, at least partly bear against a predetermined bearing surface (201, 202) of the LED module such that a controlled force which is independent of the first fixation means is applied the bearing surface of the LED module by means of the resilient portion.