In-Canal Receiver Housing With Circuitous Wax Trap
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Solution Overview
Problem
Hearing aid components, particularly receiver speakers, are prone to damage from earwax accumulation when positioned in the ear canal, leading to reduced acoustic performance and early device failure due to clogged barriers and difficulty in replacement.
Innovation Solution
A hearing aid assembly with a receiver housing featuring a circuitous receiver acoustic channel and a pass-through passage, combined with an earbud that covers the open side of the channel, to prevent earwax entry and facilitate easy cleaning, along with a filter at the receiver opening to further reduce debris ingress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a barrier is used to prevent earwax from entering the receiver housing, then the receiver speaker is protected from damage, but the barrier can become clogged and reduce acoustic performance
Solution Approach 1:
The acoustic channel is divided into multiple segments with different characteristics. The first portion allows direct sound transmission while the second portion provides a tortuous path that traps earwax. This segmentation enables the system to simultaneously protect the receiver and maintain acoustic performance by separating the protective function from the acoustic transmission function.
Solution Approach 2:
A wax trap cavity is introduced as an intermediary structure between the acoustic channel and the receiver housing. This cavity acts as a mediator that captures earwax particles before they can reach the receiver speaker, while allowing sound waves to pass through unaffected. The intermediary structure resolves the contradiction by providing protection without blocking acoustic transmission.
2Reliability
If a barrier is used to prevent earwax entry, then the receiver speaker is protected, but the barrier is difficult to replace due to tiny size
Solution Approach 1:
The wax trap cavity is designed to be self-cleaning through its tortuous geometry. Earwax naturally accumulates in the curved portions of the channel where it cannot reach the receiver speaker. This eliminates the need for manual barrier replacement while maintaining protective function, as the structure itself provides ongoing protection without requiring user intervention.
3Productivity
If the receiver housing has openings for acoustic transmission, then sound can reach the user's ear, but earwax can easily enter the housing through these openings
Solution Approach 1:
Instead of trying to block earwax from entering through the acoustic openings, the design inverts the approach by creating a tortuous path that actively directs earwax away from the receiver. The acoustic channel curves back on itself, using the same openings needed for sound transmission to also serve as a trap for earwax particles.
Solution Approach 2:
The acoustic channel incorporates curved and tortuous geometries rather than straight paths. These curved sections create areas where earwax particles can become trapped due to centrifugal forces and changes in flow direction, while sound waves continue to transmit efficiently through the curved path to the user's ear.
Data Source
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AI summary
A hearing aid assembly includes a receiver speaker enclosed within a receiver housing. The receiver housing defines a circuitous receiver acoustic channel, wherein the receiver channel defines an open side along at least a portion of the receiver channel. The receiver channel also defines a pass-through passage extending from a first side of the receiver housing to a second side of the receiver housing, wherein the pass-through passage is partially defined by the wall defining a receiver opening. The hearing aid assembly also includes an earbud configured to fit over at least a portion of the receiver housing and partially cover the open side of the receiver channel.