Audio Transducer Conductor Routing for EMI Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional transducers in audio devices often generate undesirable noise and electromagnetic interference (EMI) due to the configuration of their conductors, which can be exacerbated by the decreasing size of devices, making it difficult to include downstream filters or shielding, and thus challenging to comply with electromagnetic radiation standards.
Innovation Solution
The transducer design features a voice coil with conductors extending from opposing sides to terminals on the same side, using conductive pathways that minimize net EMI, potentially eliminating the need for downstream filtering and shielding by canceling electromagnetic fields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If traditional conductor configuration is used in transducers, then device size can be reduced, but electromagnetic interference and noise increase
Solution Approach 1:
The patent applies the 'Blessing in disguise' principle by configuring the second conductor to generate an electromagnetic field that counteracts the harmful EMI produced by the first conductor. The second conductor is positioned and routed to create a beneficial opposing electromagnetic field that cancels out the noise and interference, converting the potential harm into a benefit by using the conductor itself to neutralize its own interference.
Solution Approach 2:
The patent employs asymmetry in the conductor configuration where the first and second conductors are positioned asymmetrically relative to the voice coil and terminals. The second conductor is specifically routed to extend from the second end of the voice coil to the second terminal in a manner that creates an opposing electromagnetic field, breaking the symmetry to achieve EMI cancellation while maintaining compact device dimensions.
2Object-affected harmful factors
If downstream filters or shielding are added to reduce EMI, then electromagnetic radiation standards can be met, but device complexity and manufacturing cost increase
Solution Approach 1:
The transducer design implements the 'Self-service' principle by making the conductor system itself responsible for reducing its own electromagnetic interference. Instead of requiring external filters or shielding components, the second conductor is configured to automatically generate a counteracting electromagnetic field that neutralizes the EMI produced by the first conductor, enabling the device to meet electromagnetic radiation standards without additional complexity.
Solution Approach 2:
The patent applies the 'Taking out' principle by removing the need for downstream filters and shielding components from the transducer design. By integrating EMI cancellation directly into the conductor configuration, the harmful EMI is addressed at the source rather than requiring separate filtering stages, thereby simplifying the overall device structure and reducing manufacturing complexity.
3Object-generated harmful factors
If conductor routing is optimized to cancel electromagnetic fields, then EMI is reduced, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies the 'Local quality' principle by optimizing the conductor routing in the critical region near the voice coil and terminals where electromagnetic field interaction occurs. The second conductor is specifically positioned and routed to create the opposing electromagnetic field where it is most effective, rather than requiring uniform precision throughout the entire conductor length. This localized optimization reduces the overall manufacturing precision requirements while still achieving EMI cancellation.
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 design reduces electromagnetic radiation emissions by 5-10 decibels, improves sound quality, and allows for smaller device footprints without compromising audio performance or increasing manufacturing costs.
Implementation Method 1
the second conductor including first and second conductive pathways that extend toward the second terminal via opposing sides of the voice coil
Data Source
AI summary
Audio device transducers are disclosed herein. In some embodiments, the audio device transducer comprises a coil, first and second terminals each disposed adjacent a first side of the coil, and first and second conductors each electrically coupled to the coil. The first conductor extends from the first end of the coil to the first terminal, and the second end extends from a second end of the coil to the second terminal. The second conductor includes a first conductive pathway and a second conductive pathway spaced apart from the first conductive pathway such that the coil is disposed between the first conductive pathway and the second conductive pathway. In some embodiments, the first conductive pathway is symmetric to the second conductive pathway about an axis extending through the coil.