Speaker Frame Arm Width Variation for Compressive Strength

Solution Overview

Problem

Conventional speaker frames face challenges in achieving high rigidity to prevent resonance while maintaining weight reduction and cost-effectiveness, as increased frame arm width for compressive strength compromises acoustic characteristics and increases weight, and alternative materials like aluminum die casting raise costs.

Innovation Solution

A speaker frame design with gradually increasing frame arm width from the edge support to the damper support portion, featuring continuous side edges forming a smooth curve and vent windows with reinforcement ribs, which enhances compressive strength without sacrificing acoustic performance or increasing weight, achieved through press-forming for cost efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the width dimension of frame arms is increased to improve compressive strength, then the rigidity and compressive strength of the speaker frame are improved, but the area of openings between frame arms is decreased, lowering sound passage and acoustic characteristics

Engineering Contradiction:

Improvecompressive strengthVSAvoidarea of openings

Core Design Contradiction:

StrengthVSArea of stationary object

Solution Approach 1:

The frame arm width is designed to vary locally along its length, being wider at the damper support portion where compressive stress concentrates and narrower at other portions. This local variation in width provides targeted strength enhancement exactly where needed while preserving opening area elsewhere, thus resolving the contradiction between compressive strength and sound passage.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Instead of uniformly increasing frame arm width in one dimension, the invention introduces curvature in the side edges of frame arms, creating a smooth curved connection at the damper support portion. This dimensional change allows the frame arm to achieve higher moment of inertia and bending resistance without proportionally increasing the linear width dimension, thereby maintaining opening area while improving compressive strength.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Strength

If the width dimension of frame arms is increased to improve compressive strength, then the rigidity is improved, but the weight of the speaker frame increases

Engineering Contradiction:

Improvecompressive strengthVSAvoidweight of speaker frame

Core Design Contradiction:

StrengthVSWeight of stationary object

Solution Approach 1:

The frame arm width is designed to vary locally along its length, being wider at the damper support portion where compressive stress concentrates and narrower at other portions. This local variation in width provides targeted strength enhancement exactly where needed while preserving opening area elsewhere, thus resolving the contradiction between compressive strength and sound passage.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Instead of uniformly increasing frame arm width in one dimension, the invention introduces curvature in the side edges of frame arms, creating a smooth curved connection at the damper support portion. This dimensional change allows the frame arm to achieve higher moment of inertia and bending resistance without proportionally increasing the linear width dimension, thereby maintaining opening area while improving compressive strength.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Strength

If aluminum die casting is used to increase compressive strength without sacrificing weight reduction, then the compressive strength is improved, but the manufacturing cost and material cost increase significantly

Engineering Contradiction:

Improvecompressive strengthVSAvoidmanufacturing cost

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The invention changes the geometric parameters of the frame arm structure, specifically the side edge configuration and width variation along the length, to achieve higher compressive strength. By optimizing these parameters within conventional press-formed steel plate construction, the invention attains improved strength without changing materials or manufacturing processes, thus avoiding the cost increase associated with aluminum die casting.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS7668333B2Speaker frame and speaker device having a speaker frame

Publication Date: 2010.02.23 TOHOKU PIONEER CORP

AI summary

A speaker frame comprising: a rear end wall; a damper support portion; an edge support portion to which an edge as an outer circumferential portion of a vibration plate is to be stuck and fixed; and plural frame arms which connect the edge support portion to the rear end wall and the damper support portion, wherein: a width of each of the frame arms increases as the position goes from the edge support portion to the damper support portion, and damper-support-portion-side end portions of side edges of adjoining frame arms are continuous with each other to form a single as an axis of symmetry, a bisector of an angle formed by the adjoining frame arms; and a single vent window is formed in each of the frame arms, and a reinforcement rib erects at a circumferential edge of the vent window.