Asymmetric Coil Winding for Core Alignment and Squeal Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The coil device experiences squealing due to magnetic attraction between the inner and outer cores, which can occur when the inner core is inclined, leading to a decrease in distance and inductance value, and is difficult to assemble with bent lead portions.
Innovation Solution
The coil device design includes an inner core with flange portions and a winding configuration where the number of turns is higher on one side of the axial direction, allowing lead portions to be connected orthogonally, maintaining a constant distance between cores and preventing inclination, thus reducing squealing and enhancing inductance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the lead portion is pulled out diagonally to connect to the terminal portion, then the wire can be connected to the terminal, but the inner core becomes inclined relative to the outer core causing squealing
Solution Approach 1:
The winding end position is preliminarily positioned at the first end portion together with the winding start position, so that the lead portion can be pulled out in a direction orthogonal to the axial direction of the winding core portion. This preliminary positioning prevents the need for diagonal pulling and maintains proper core alignment during assembly.
Solution Approach 2:
The number of turns of the wire along the radial direction is made larger on one side in the axial direction than on the other side. This asymmetric winding configuration stabilizes one side of the coil device during mounting, preventing the inner core from inclining relative to the outer core and eliminating squealing.
2Ease of operation
If the inner core is inclined with respect to the outer core, then assembly may be easier, but the distance between cores decreases locally causing stronger magnetic attraction and squealing
Solution Approach 1:
The winding end position is preliminarily positioned at the first end portion together with the winding start position, enabling the lead portion to be pulled out orthogonally. This prevents diagonal pulling that would cause core inclination and maintains constant distance between the inner and outer cores, reducing magnetic attraction and squealing.
Solution Approach 2:
The asymmetric winding configuration with more turns on one side stabilizes the coil device during mounting, preventing the inner core from inclining relative to the outer core. This maintains proper spacing between cores and reduces harmful magnetic attraction forces.
3Stability of the object's composition
If the number of turns is increased on one side to stabilize the coil device, then vibration is suppressed, but the device complexity increases
Solution Approach 1:
The number of turns of the wire along the radial direction is made larger on one side in the axial direction than on the other side. This asymmetric winding configuration stabilizes one side of the coil device during mounting, preventing vibration and squealing while maintaining relatively simple construction.
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 stabilizes the inner core's posture, prevents squealing, maintains inductance, and simplifies assembly by avoiding bent lead portions, ensuring reliable operation and easy manufacturing.
Implementation Method 1
a coil device includes: an inner core (20) including a winding core portion (22) wound by a wire (30)
Implementation Method 2
squealing may arise after mounting a substrate due to the magnetic attraction between the inner core and the outer core
Data Source
AI summary
A coil device includes: an inner core including a winding core portion wound by a wire, an upper flange portion with a first end portion on one side of the winding core portion, and a lower flange portion with a second end portion on the other side of the winding core portion; an outer core having an insertion hole and disposed outside the inner core, the inner core being inserted to the insertion hole; and a pair of terminal portions on the outer core, lead portions of the wire connect to the terminal portions. The number of wire turns along a radial direction of the winding core portion is larger on one side of the winding core portion than on the other side, and a wire winding end position is at the first end portion on the one side of the winding core portion with a wire winding start position.