Headphone Speaker Baffle Cavity for Passive Noise Reduction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Noise-canceling headphones have poor ambient-noise reduction performance when the noise-reducing circuitry is not functioning, leading to battery consumption and the need for frequent battery replacements, especially in noisy environments like vehicles.

Innovation Solution

The design incorporates a dual-wall structure in the speaker sections with a protruding round wall and a unit case, along with a battery container that protrudes from the baffle, enhancing sound insulation by creating a cavity that reduces ambient noise without relying on active noise-canceling circuitry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If noise-canceling headphones are used with active noise-reducing circuitry, then ambient noise reduction performance is improved, but battery consumption increases and requires frequent battery replacement

Engineering Contradiction:

Improveambient noise reduction performanceVSAvoidbattery consumption

Core Design Contradiction:

Object-affected harmful factorsVSUse of energy by moving object

Solution Approach 1:

The invention divides the noise reduction function into two independent parts: passive sound insulation structure (physical barrier) and active noise-canceling circuitry (electronic system). The passive structure with sealed ear cups and cushioning materials provides baseline noise reduction without energy consumption, while the active circuitry supplements it when needed. This segmentation allows users to benefit from noise reduction even when the battery is depleted.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements passive sound insulation structures (thick cushioning materials, sealed ear cups, and noise-insulating walls) that provide noise reduction protection in advance, before the active noise-canceling function is engaged. This ensures that even when the battery is depleted, users still have a baseline level of noise protection from the passive structural elements.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Object-affected harmful factors

If noise-canceling headphones rely solely on active noise-reducing circuitry, then high noise reduction performance is achieved, but performance deteriorates when circuitry is inactive

Engineering Contradiction:

Improvenoise reduction performanceVSAvoidperformance consistency

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The invention merges passive sound insulation structures (physical barriers, cushioning materials, sealed designs) with active noise-canceling circuitry into a unified headphone system. The passive structures provide continuous noise reduction regardless of battery status, while the active circuitry enhances performance when powered. This combination ensures reliable noise reduction performance in all operational states.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs passive sound insulation structures with optimized physical parameters (cushioning thickness, material density, ear cup sealing) that provide consistent noise reduction across different frequencies and environmental conditions. These parameter-optimized passive elements ensure reliable performance independent of the active circuitry's operational state.

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If headphones use passive design without active circuitry, then battery-free operation is achieved, but sound insulation performance against ambient noises is insufficient

Engineering Contradiction:

Improvebattery-free operationVSAvoidsound insulation performance

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The invention implements extensive passive sound insulation structures (thick cushioning, sealed ear cups, noise-insulating walls) that provide a substantial baseline level of noise reduction without requiring any active power consumption. This partial noise reduction is sufficient for many situations, and the active circuitry can be added optionally to enhance performance when needed, without compromising the battery-free operational capability.

Inventive Principle:

Principle #16Partial or excessive action

Data Source

PatentUS8861766B2Headphones

Publication Date: 2014.10.14 JVC KENWOOD CORP

AI summary

A headphone set has at least one speaker section. The speaker section includes a baffle having at least one sound emitting hole, a surrounding wall formed on the baffle so that the surrounding wall protrudes from the baffle and surrounds the sound emitting hole, a speaker unit installed within the surrounding wall and having a first surface to face the sound emitting hole and an opposite second surface, a unit case provided as touching the surrounding wall and covering the second surface of the speaker unit, a first cavity existing as enclosed by the unit case and the second surface of the speaker unit, and a housing provided as touching the baffle and covering the unit case, a second cavity existing as enclosed by the housing, the unit case, and the baffle.