Loudspeaker Membrane Stiffening Element for Resonance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conical loudspeaker membranes often require a minimum height for low-frequency sound reproduction and controlled behavior at higher frequencies, but non-conical membranes can lead to deterioration in sound reproduction, particularly at mid and high frequencies.
Innovation Solution
Incorporating a stiffening element that extends around the drive unit to reinforce the base region of the membrane, reducing deformation and shifting the first break-up resonance to a higher frequency, thereby achieving a more balanced frequency response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If a non-conical membrane is used to reduce loudspeaker height, then the height is reduced, but the sound reproduction deteriorates at mid and high frequencies
Solution Approach 1:
The patent applies local quality by adding a stiffening element specifically at the base region of the membrane where it connects to the drive unit. This localized reinforcement provides the necessary stiffness to control membrane deformation and improve mid/high frequency sound reproduction, while the rest of the membrane maintains its non-conical shape to keep the loudspeaker height reduced.
2Length of stationary object
If the membrane height is reduced to make the loudspeaker more compact, then the height is reduced, but the membrane stiffness becomes insufficient for low frequency reproduction
Solution Approach 1:
The stiffening element is placed locally at the base region of the membrane to provide the necessary stiffness for low frequency reproduction. This allows the membrane to maintain a reduced overall height while having localized reinforcement where it is most needed for structural integrity and acoustic performance.
Solution Approach 2:
The patent uses a composite structure combining the membrane material with a stiffening element at the base region. This composite approach allows the membrane to achieve both reduced height and sufficient stiffness by integrating materials or structures with different mechanical properties in a unified design.
3Strength
If a stiffening element is added to improve membrane stiffness, then the stiffness is increased, but the device complexity increases
Solution Approach 1:
The stiffening element is applied only at the base region of the membrane where it connects to the drive unit, rather than throughout the entire membrane structure. This localized approach provides the necessary stiffness improvement while minimizing the increase in device complexity and maintaining manufacturing simplicity.
Data Source
AI summary
The present invention provides: a loudspeaker including a frame, a drive unit, and a membrane;the membrane having an inner edge, an outer edge which is suspended from the frame, and a membrane body which is between the inner and outer edges and extends around the drive unit;the drive unit having a stationary part secured to the frame and a translatable part secured to the inner edge of the membrane;the membrane body including a dished portion which, has a depth that increases from said inner and outer edges towards a base region of the dished portion located between said edges;wherein the loudspeaker includes a stiffening element which extends around the drive unit and stiffens the membrane body at the base region of the dished portion, so as to reinforce the membrane against deformation in the base region. By including the stiffening element, it has been found that the first break-up resonance of the membrane is shifted to a higher frequency and has reduced amplitude. As a consequence, the loudspeaker according to this aspect has a more balanced frequency response, particularly at mid and high frequency ranges.