Adjustable Spring Assembly for Bone Anchored Hearing Aid Vibrator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Manufacturing tolerances in suspension springs and electromagnetically driven masses in bone anchored hearing aids often result in peak frequencies mismatching the desired interval, leading to poor production yield and suboptimal frequency delivery.
Innovation Solution
An adjustable spring assembly with a planar suspension spring and rotatable disk-shaped adjusting means allows for stepless adjustment of the spring rate, enabling precise movement of the resonance peak into a desired frequency range without disassembly, using the same parts to produce hearing aids with varying frequency characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If manufacturing tolerances are applied to suspension springs and electromagnetically driven masses, then production efficiency is improved, but peak frequency matching deteriorates
Solution Approach 1:
The suspension spring is designed with an adjustable mechanism that allows the spring rate to be dynamically modified after assembly. A adjusting means with a pad can be rotated to different angular positions, changing the degree to which the pad engages with the suspension spring, thereby continuously adjusting the spring rate and peak frequency without disassembly or replacement of parts.
Solution Approach 2:
The invention changes the physical parameter of the suspension spring (spring rate) by modifying its effective stiffness through the adjusting means. By rotating the adjusting means, the pad's position changes, altering the constraint on the suspension spring and thereby adjusting the spring rate and peak frequency to match desired values despite manufacturing tolerances.
2Manufacturing precision
If the peak frequency is adjusted by replacing parts or disassembling the vibrator, then frequency matching is improved, but device complexity and manufacturing time increase
Solution Approach 1:
The suspension spring is designed with an adjustable mechanism that allows the spring rate to be dynamically modified after assembly. A adjusting means with a pad can be rotated to different angular positions, changing the degree to which the pad engages with the suspension spring, thereby continuously adjusting the spring rate and peak frequency without disassembly or replacement of parts.
Solution Approach 2:
The adjusting means is designed to be self-contained within the vibrator assembly, allowing operators to adjust the peak frequency directly on the assembled device without requiring external tools or specialized equipment. The rotation of the adjusting means automatically modifies the spring rate through the pad's engagement with the suspension spring.
3Shape
If the suspension spring is designed as a planar spring, then the flat design is improved, but adjustment capability may be limited
Solution Approach 1:
The suspension spring is designed with an adjustable mechanism that allows the spring rate to be dynamically modified after assembly. A adjusting means with a pad can be rotated to different angular positions, changing the degree to which the pad engages with the suspension spring, thereby continuously adjusting the spring rate and peak frequency without disassembly or replacement of parts.
Solution Approach 2:
The adjusting means introduces a rotational dimension to the otherwise planar spring assembly. By rotating the adjusting means around the axis of the suspension spring, the pad's radial position changes, enabling continuous adjustment of the spring rate while maintaining the overall flat profile of the vibrator.
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 solution allows for consistent production of bone anchored hearing aids that can deliver enhanced gain in both low and high frequency ranges, maintaining a flat design and constant magnetic air gap, while preventing mass distribution issues and tilting, thereby improving production yield and frequency matching.
Implementation Method 1
a resonant system formed by an electromagnetically driven mass suspended by a suspension spring
Implementation Method 2
the vibrator resonates at a specific peak frequency
Implementation Method 3
an electromagnetically driven mass
Implementation Method 4
the suspension spring is designed as a planar spring
Data Source
Figure 1
Figure 2~4
Figure 5
AI summary
Spring assembly (10) as part of a vibrator (100) for a bone anchored hearing aid, wherein the spring assembly (10) comprises a suspension spring (3, 5) having a first end (11) immovably connected to a mass (20) of the vibrator (100) and a second end (12) immovably connected to a coupling (30) attachable to a user's skull bone and comprised by the vibrator (100), wherein the spring assembly (10) comprises an adjusting means (1) adapted to adjust a spring rate (K) of the suspension spring (3, 5) between a first spring rate (K1) and a second spring rate (K2), the first rate (K1) being higher than the second rate (K2), so as to move a resonance peak (P) of the vibrator (100).