Magnetic Circuit System With Variable Thickness Top Plate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic circuit systems in transducers, such as speakers, suffer from non-linear distortion due to uneven magnetizing force factors, which are influenced by the production of magnetic flux and coil displacement.
Innovation Solution
A magnetic circuit system design featuring a yoke with a center pole, a magnet with a through hole, and a top plate with a varying thickness, creating a magnetic gap between the yoke's center pole and the top plate, ensuring a consistent magnetic flux distribution and thus reducing non-linear distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional magnetic circuit system with uniform top plate thickness is used, then the structure is simple and easy to manufacture, but the magnetizing force factor becomes uneven during coil vibration, causing non-linear distortion
Solution Approach 1:
The top plate is designed with non-uniform thickness, where the first portion (adjacent to the magnet) has a first thickness and the second portion (away from the magnet) has a second thickness different from the first. This local variation in thickness creates corresponding variations in magnetic flux distribution that compensate for the non-linear distortion caused by coil vibration, thereby achieving a more uniform magnetizing force factor throughout the magnetic gap.
2Reliability
If the top plate has uniform thickness, then the device structure is simple, but the magnetic flux distribution becomes uneven during coil operation, leading to distortion
Solution Approach 1:
The thickness parameter of the top plate is deliberately varied across different regions. The first portion adjacent to the magnet has a first thickness while the second portion away from the magnet has a second thickness. This parameter change in the top plate's geometric dimension directly influences the magnetic flux distribution, allowing compensation for non-linear effects and improving the linearity of transducer operation.
3Manufacturing precision
If a non-uniform top plate thickness design is implemented, then the magnetizing force factor remains consistent during coil vibration, but the manufacturing process becomes more complex
Solution Approach 1:
The top plate is designed with non-uniform thickness, where the first portion (adjacent to the magnet) has a first thickness and the second portion (away from the magnet) has a second thickness different from the first. This local variation in thickness creates corresponding variations in magnetic flux distribution that compensate for the non-linear distortion caused by coil vibration, thereby achieving a more uniform magnetizing force factor throughout the magnetic gap.
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
The design achieves a consistent magnetic force application along the voice coil, significantly improving the linearity of transducer operations by maintaining a uniform magnetic flux distribution, thereby reducing distortion in speakers and similar devices.
Implementation Method 1
A magnetic gap is defined between an inner surface of the top plate and an outer surface of the centre pole of the yoke
Implementation Method 2
when electrified, the coil will be given a magnetizing force F, and the force F is determined by the product of magnetic flux (B), displacement of the coil (L), and current applied on the coil (I)
Data Source
AI summary
A magnetic circuit system includes a T-shaped yoke, a magnet, and a top plate. The top plate has a center hole, an internal end around the center hole thereof, and two projecting elements provided separately on upper surface and lower surface of the internal end, which improves non-linear distortion of a transducer using the magnetic circuit system.