Foldable Device Magnet Distance Adjustment via Bimetal Thermal Expansion

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Foldable electronic devices face issues with maintaining a consistent magnetic force between magnets due to temperature changes, leading to instability in the folded state, either failing to close properly at high temperatures or being difficult to open at low temperatures.

Innovation Solution

Incorporating a bimetal member with different thermal expansion coefficients between the magnets and a support member with a reception space that allows the bimetal member to bend, adjusting the distance between the magnets as temperature changes, thus maintaining a consistent magnetic force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If magnets with high magnetic force are used, then the folded state is maintained well at low temperature, but the device becomes difficult to open due to excessive attraction force

Engineering Contradiction:

Improvemaintenance of folded stateVSAvoidease to open device

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent introduces a bimetal member that dynamically adjusts the distance between magnets based on temperature changes. At different temperatures, the bimetal member bends to different degrees, automatically modulating the magnetic attraction force to maintain ease of operation while ensuring reliable folded state maintenance.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the physical parameter of the bimetal member (length/distance between magnets) in response to temperature changes. By using a bimetal member with specific thermal expansion properties, the system automatically adjusts the magnetic interaction parameter to resolve the contradiction between strong attraction and ease of opening.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If magnets are used to maintain folded state, then the device can be held in folded position, but temperature changes cause magnetic force variation leading to unstable folded state

Engineering Contradiction:

Improvestability of folded stateVSAvoidconsistency of magnetic force

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent directly applies thermal expansion principles by using a bimetal member composed of two different metals with different thermal expansion coefficients. When temperature changes, the bimetal member expands or contracts, automatically compensating for magnetic force variations to maintain stable folded state.

Inventive Principle:

Principle #37Thermal expansion

Solution Approach 2:

The patent converts the harmful effect of temperature changes on magnetic force into a beneficial automatic adjustment mechanism. The temperature-induced bending of the bimetal member, which would normally be considered a disturbance, becomes the driving force that maintains consistent magnetic attraction across varying temperatures.

Inventive Principle:

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

3Reliability

If the distance between magnets is reduced to increase magnetic force, then folded state maintenance improves, but the device structure becomes more complex

Engineering Contradiction:

Improveforce of attraction between magnetsVSAvoidstructural complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The bimetal member serves multiple functions: it acts as both a structural support element and a temperature-compensation mechanism. By integrating these functions into a single component, the patent avoids adding extra complexity while achieving the goal of maintaining strong magnetic attraction.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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

This solution ensures a consistent manipulation experience during folding by compensating for changes in magnetic force due to temperature, allowing the device to maintain a stable folded state without user interference.

Implementation Method 1

the first bimetal member has a first length at a first temperature and a second length, which is longer than the first length, at a second temperature, which is higher than the first temperature

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 2

a first bimetal member disposed between the flexible display and the first support member

Methodology Applied

Scientific EffectBimetallic strip effect: Bi-Metallic Strip

Data Source

PatentUS11204624B2Foldable electronic device including magnets

Publication Date: 2021.12.21 SAMSUNG ELECTRONICS CO LTD

AI summary

An electronic device is provided, which includes a first housing, a second housing, a hinge structure, a flexible display configured to form a front surface of the first housing and the second housing while the electronic device is in an unfolded state, a first support member disposed between the flexible display and the first housing, a first bimetal member disposed between the flexible display and the first support member, a first magnet disposed between the flexible display and the first bimetal member, and a second magnet disposed between the flexible display and the second housing. The first bimetal member has a first length at a first temperature and a second length longer than the first length at a second temperature higher than the first temperature. The first support member has a reception space having a length greater than or equal to the first length and less than the second length that provides space for the first bimetal member to bend at the second temperature.