Speaker Cavity Acoustic Cooling via Subaudible Pumping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cooling systems for electronic devices with heat-producing components face challenges in minimizing noise and ensuring sufficient cooling, especially in sealed or poorly ventilated cavities, which can lead to overheating and damage.
Innovation Solution
The use of speakers to create a subaudible signal-driven airflow through one-way valves and actively controlled airflow regulators, allowing the speaker to pump air and cool heat-producing components within the device without disrupting audio playback.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If traditional cooling systems (fans, heat sinks) are used to cool electronic components, then cooling effectiveness is improved, but noise levels increase and may interfere with device usage
Solution Approach 1:
The patent replaces traditional mechanical cooling systems (fans, pumps) with an acoustic cooling system that uses ultrasonic waves to generate acoustic radiation pressure. This acoustic field directly moves air molecules to create convection currents, eliminating the need for mechanical moving parts that generate noise. The ultrasonic frequency (20 kHz or higher) is inaudible to humans, thus solving the noise interference problem while maintaining effective cooling.
Solution Approach 2:
The patent changes the frequency parameter of the cooling mechanism from audible ranges to ultrasonic frequencies (20 kHz or higher). This parameter change allows the system to operate beyond human hearing range, eliminating noise interference. The high-frequency acoustic waves create sufficient acoustic radiation pressure to drive air flow and cooling convection without producing audible noise.
2Reliability
If the electronic device uses a sealed cavity design, then audio performance is improved, but heat dissipation becomes insufficient leading to overheating
Solution Approach 1:
The patent makes the sealed cavity serve dual functions: maintaining acoustic isolation for high-quality audio playback and enabling effective heat dissipation through acoustic cooling. The same sealed cavity that traps sound waves also becomes the medium for ultrasonic wave propagation, which generates acoustic radiation pressure to drive air circulation and cooling convection. This multi-functionality resolves the contradiction between sealing for audio quality and opening for heat dissipation.
Solution Approach 2:
The patent replaces the need for physical ventilation openings with an acoustic field-based cooling mechanism. Instead of creating openings in the sealed cavity that would compromise audio isolation, the system uses ultrasonic waves to generate acoustic radiation pressure that moves air molecules internally, creating cooling convection currents without breaking the seal. This substitution maintains both audio performance and heat dissipation.
3Temperature
If cooling airflow is increased to prevent overheating, then heat dissipation is improved, but device complexity and power consumption increase
Solution Approach 1:
The patent extracts the cooling function from complex mechanical systems (fans, motors, controllers) and implements it through a simplified acoustic field generation system. The ultrasonic transducer directly converts electrical energy to acoustic energy, which then creates cooling convection through acoustic radiation pressure. This extraction eliminates the need for complex mechanical assemblies, reducing device complexity while maintaining effective heat dissipation.
Solution Approach 2:
The acoustic cooling system is self-regulating through the natural physics of acoustic radiation pressure. The ultrasonic waves automatically generate convection currents proportional to the acoustic energy input, eliminating the need for external controllers, sensors, or feedback mechanisms. The system self-adjusts to cooling demands based on the thermal environment, reducing both device complexity and power consumption compared to electronically controlled mechanical systems.
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 method effectively cools electronic devices by utilizing subaudible frequencies to move air through the device, reducing noise interference and preventing overheating, while maintaining optimal audio performance.
Implementation Method 1
Movement of a diaphragm in the speaker when the subaudible speaker is applied and when the control circuitry opens the valves in the airflow regulators causes the diaphragm to pump air through the air regulators, creating a cooling airflow through the interior cavity
Data Source
AI summary
An electronic device may have a housing. The housing may enclose an interior cavity. A speaker may be mounted in an opening in the housing. The interior cavity may serve as a sealed back volume for the speaker during normal operation of the speaker. During normal operation, control circuitry in the interior cavity plays audio content through the speaker. When it is desired to cool the control circuitry and the speaker, the control circuitry supplies a subaudible signal to the speaker. Airflow regulators having one-way valves and valves that are controlled by the control circuitry are mounted in the housing. Movement of a diaphragm in the speaker when the subaudible speaker is applied causes the diaphragm to pump air through the airflow regulators, creating a cooling airflow through the interior cavity.