Torsional Heat Pipe for Thin Clamshell Hinge Thermal Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current heat transfer systems across hinges in electronic devices, such as laptops, face challenges with high thermal resistance and reliability due to the need for flexible heat pipes with large bend radii, which can lead to failure under fatigue and are unsuitable for thin clamshell designs.
Innovation Solution
A torsional heat pipe with a flexible and rotatable torsion portion at the hinge area, allowing deformation and reducing stress, coupled with a hermetic or quasi-hermetic seal, enables continuous heat transfer from a heat source in one housing to a heat spreader in another, using a 2-phase heat transfer mechanism.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a flexible heat pipe with large bend radius is used to transfer heat across a hinge, then heat transfer capability is maintained, but the device thickness increases and reliability decreases due to fatigue failure
Solution Approach 1:
The heat pipe is divided into three distinct segments: a first static portion in the base housing, a second static portion in the lid housing, and a torsion portion in the hinge. This segmentation allows each segment to be optimized for its specific function - the static portions maintain structural integrity while the torsion portion handles rotational movement with controlled stress distribution, eliminating the need for a large bend radius and reducing fatigue failure risk
Solution Approach 2:
The torsion portion is designed to be rotatable and flexible, allowing it to dynamically adapt to the hinge's rotational movement. This dynamic design enables the heat pipe to maintain thermal contact across the hinge while accommodating device opening and closing motions, solving both the reliability and thickness problems simultaneously
2Strength
If a rigid heat pipe is used to transfer heat across a hinge, then structural integrity is maintained, but the heat pipe cannot accommodate hinge rotation and fails under stress
Solution Approach 1:
Different portions of the heat pipe are assigned different mechanical properties: the first and second portions are rigid to maintain structural integrity and thermal conductivity, while the torsion portion is flexible and rotatable to accommodate hinge movement. This local differentiation of properties allows the heat pipe to simultaneously maintain strength and adaptability
Solution Approach 2:
The torsion portion is specifically designed with rotational capability to dynamically respond to hinge movement. This dynamic segment allows the otherwise rigid heat pipe to accommodate the changing geometric constraints imposed by hinge rotation, preventing stress failure while maintaining overall structural integrity
3Length of moving object
If a heat pipe system is designed for thin clamshell devices, then device thickness is reduced, but heat transfer reliability decreases due to increased stress concentration
Solution Approach 1:
Dividing the heat pipe into segmented portions allows the torsion portion to be specifically engineered to handle stress from thin-device constraints. The segmentation isolates the stress concentration to the torsion portion's designed flex point, preventing failure propagation while enabling the overall device to be thinner
Solution Approach 2:
The torsion portion is pre-designed with controlled flexibility and stress distribution characteristics to cushion against the high stresses that would otherwise concentrate in a thin-device configuration. This beforehand cushioning through intentional design of the torsion portion's mechanical properties prevents reliability failures while maintaining the thin form factor
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 provides efficient, low-resistance heat transfer across the hinge, enhancing device performance, acoustics, and allowing for higher power devices in thinner, quieter systems without the need for fans, while maintaining reliability through uniform stress/strain fields and buckling resistance.
Implementation Method 1
enables continuous heat transfer from a heat source in one housing to a heat spreader in another, using a 2-phase heat transfer mechanism
Implementation Method 2
provides efficient, low-resistance heat transfer across the hinge
Data Source
AI summary
Particular embodiments described herein provide for an electronic device that can be configured to include a torsional heat pipe. The torsional heat pipe can include a first housing static portion located in a first housing of an electronic device, where the first housing static portion is coupled to a heat source, a second housing static portion located in a second housing of the electronic device, where the second housing static portion is coupled to a heat spreader, and a torsion portion located in a hinge of the electronic device, where the hinge rotatably couples the first housing to the second housing and the torsion portion rotates as the second housing rotates relative to the first housing and the torsion portion couples the first housing static portion to the second housing static portion.