Foldable FPCB Hinge Guidance for Asymmetry and Wear Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Flexible printed circuit boards (FPCBs) in foldable electronic devices suffer from deformation and damage due to repeated folding and unfolding, leading to a shortened lifespan and asymmetrical shapes, which can be exacerbated by friction with housings and components.

Innovation Solution

A foldable electronic device design incorporating a flexible printed circuit board (FPCB) with a hinge structure and a guide protrusion, along with a reinforcement portion that guides the FPCB's movement to prevent asymmetrical shapes and protect it from damage during folding and unfolding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the FPCB is freely bent to accommodate folding movements, then the device achieves foldability and portability, but the FPCB deforms asymmetrically and its lifespan shortens due to repeated folding

Engineering Contradiction:
ImprovefoldabilityVSAvoidFPCB lifespan
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The FPCB is divided into distinct functional segments: a flexible portion for bending movements and a reinforcement portion with guide protrusions for maintaining shape. This segmentation allows each part to perform its specific function optimally while working together to solve the contradiction between foldability and durability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The reinforcement portion acts as an intermediary structure between the flexible FPCB and the hinge housing. It mediates the interaction by providing guide protrusions that constrain the FPCB's movement path, preventing asymmetric deformation while allowing necessary folding movements.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the FPCB moves freely during folding, then the device achieves smooth folding operation, but friction with housing and components causes damage and asymmetrical shapes

Engineering Contradiction:
Improvefolding operationVSAvoidfriction damage
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The reinforcement portion with guide protrusions serves as an intermediary that mediates between the FPCB and the hinge housing. It guides the FPCB's movement to follow a predetermined path, reducing harmful friction and contact with other components while maintaining smooth folding operation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The guide protrusions on the reinforcement portion enable the FPCB to self-constrain its movement path during folding. The FPCB automatically follows the guide protrusions' trajectory, eliminating the need for external constraints and reducing friction with other device components.

Inventive Principle:
Principle #25Self-service

3Reliability

If the FPCB is reinforced to prevent deformation, then the FPCB maintains its shape and lifespan, but the structure becomes more complex

Engineering Contradiction:
ImproveFPCB shape stabilityVSAvoidFPCB structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The reinforcement portion is merged with the FPCB as an integrated component rather than a separate attachment. This combining approach provides shape stability and guidance functionality while minimizing additional structural complexity and assembly steps.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The reinforcement portion performs multiple functions simultaneously: it reinforces the FPCB to prevent deformation, provides guide protrusions for movement constraint, and maintains electrical connection integrity. This multi-functionality reduces the need for additional separate components.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP4290836B1Foldable electronic device
Publication Date: 2026.04.15 SAMSUNG ELECTRONICS CO LTD
  • EP4290836B1 patent drawingFigure 1
  • EP4290836B1 patent drawingFigure 2A
  • EP4290836B1 patent drawingFigure 2B

AI summary

According to an embodiment of the disclosure, a foldable electronic device may comprise a flexible printed circuit board (FPCB), a hinge structure connecting a first housing and a second housing, a hinge housing receiving at least a portion of the hinge structure and the FPCB and including a guide protrusion protruding upward from an inner surface, and a reinforcement portion coupled to the FPCB and including a guide portion for guiding a vertical movement of the FPCB along the guide protrusion in response to a movement of the first housing and the second housing.