Jounce Bumper Recess Structure for Progressive Suspension Stiffness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current spring elements, such as jounce bumpers, face challenges in manufacturing due to complex geometries required for soft initial stiffness and progressive stiffness, leading to increased production costs and inefficiencies.
Innovation Solution
A spring element design featuring a recess in the circumferential outer surface that collapses upon compression, allowing for easier manufacturing while maintaining initial deformation softness and progressive stiffness, with the recess extending inward to define a hollow space and potentially extending through the base body or to a predetermined depth, facilitating molding and demolding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If elaborate geometrical designs with encircling bending lips are used to achieve soft initial stiffness and progressive stiffness, then the spring element achieves satisfactory deformation characteristics, but the molding shape becomes complicated and manufacturing becomes difficult
Solution Approach 1:
The spring element is divided into distinct functional zones: a base portion with substantially constant cross-section and an end portion with varying cross-section. The end portion is further segmented into multiple recesses (first, second, and third recesses) at different locations, each contributing to different aspects of the force-travel characteristic. This segmentation allows complex deformation behavior to be achieved through simpler, more manufacturable geometric features.
Solution Approach 2:
Different regions of the spring element are given different cross-sectional properties to achieve specific functions. The base portion has substantially constant cross-section for structural stability, while the end portion has varying cross-section with multiple recesses to provide soft initial stiffness and progressive stiffness. This local differentiation of geometric properties allows the spring to achieve sophisticated deformation characteristics without requiring elaborate overall geometry.
2Ease of operation
If the spring element is designed with soft initial stiffness behavior, then minimal resistance is provided at the initiation of deformation, but the overall impact forces on the spring element are significant requiring progressive increase in stiffness
Solution Approach 1:
The spring element's stiffness is made dynamic rather than static. The varying cross-section of the end portion, with its multiple recesses, causes the stiffness to change progressively during compression. At small deformations, the geometry provides soft initial stiffness for comfortable operation. As compression increases, the effective stiffness progressively increases to handle significant impact forces. This dynamic stiffness characteristic is achieved through the geometric design rather than active control mechanisms.
Solution Approach 2:
The cross-sectional parameters of the spring element are deliberately varied along its length. The end portion has a varying cross-section with multiple recesses that change the second moment of area and other geometric parameters. This parameter variation allows the spring to exhibit soft initial stiffness when the cross-section is larger at the ends, while providing progressive stiffening as compression progresses and the effective load-bearing area changes. This enables the spring to adapt its mechanical properties to different operational conditions.
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 simplifies the molding process, reduces production costs, and achieves a balance between initial deformation softness and progressive stiffness, enhancing the spring element's operational characteristics.
Implementation Method 1
the base body being elastically deformable between an uncompressed basic state and a compressed state in which the base body is at least partially compressed in the direction of the longitudinal axis
Implementation Method 2
They are used in particular as spring and damping elements, typically, to support the main vehicle suspension spring and to limit the deflection of the suspension and the wheel travel
Data Source
AI summary
A spring element, in particular a jounce bumper, for a jounce bumper assembly, contains a longitudinal axis, a base body extending along the longitudinal axis, and an end portion configured for being brought into contact with a vehicle part moving relatively to the spring element. The base body is elastically deformable between an uncompressed basic state and a compressed state in which the base body is at least partially compressed in the direction of the longitudinal axis. The end portion contains a circumferential outer surface, and at least one recess in the circumferential outer surface. The recess extends inwards and defines a hollow space in the base body.