This paper discusses the operating principles and basic construction of a diaphonic pump, which is a newly invented device for harvesting the energy inherent in sound waves and using it to pump air, thereby pressurizing a vessel. Although this device is of general utility, the embodiment discussed in this paper is used to harvest sound energy from the speaker (balanced armature transducer) of a personal listening device (headset or hearing aid), and use this as a power source to inflate a bubble in the listener’s ear, thereby creating an acoustic seal. The diaphonic pump utilizes a natural asymmetry in the flow pattern when fluid is alternatingly pushed and pulled, back and forth through a small orifice known as a “synthetic jet”. Sound waves provide the alternating flow pattern across the synthetic jet orifice. Prototype diaphonic pumps were built, which attach to a back volume of a balanced armature transducer, and are small enough that the whole assembly, transducer and pump, can fit in a human ear canal.
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