Windscreen Wiper Blade Retention with Flexible Semi-Rigid Hooks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing windscreen wiper devices require intricate and expensive tools to achieve a precise fit between the longitudinal strip and mounting channel, leading to issues with wear if the strip is too large or small.
Innovation Solution
The use of a softer material for the spoiler allows the second retention means to bend, enabling a close fit between the longitudinal strip and groove, even if the strip is larger or smaller, and the integration of semi-rigid or hook-shaped retention means ensures secure retention without the need for coextrusion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the longitudinal strip is made larger or smaller in width, then it can accommodate variations in mounting channel dimensions, but it cannot be inserted into or retains with play in the mounting channel
Solution Approach 1:
The second retention means are designed to be movable relative to the upper part, allowing them to bend laterally and outwardly during insertion and then return to a fixed position to securely retain the longitudinal strip. This dynamic capability enables the mounting channel to adapt to different strip widths while ensuring a secure fit without play during operation.
Solution Approach 2:
The retention means are made from a softer material than the upper part, allowing their physical state to change during insertion (bending outwardly) and then return to their original state. This parameter change in material softness enables the mounting channel to accommodate dimensional variations while maintaining a reliable, play-free fit.
2Manufacturing precision
If the longitudinal strip and mounting channel are dimensioned for a close fit, then secure retention is achieved, but intricate and expensive tools are required for manufacturing
Solution Approach 1:
The mounting channel is divided into two functional parts: the upper part providing structural support and the second retention means providing flexible retention. This segmentation allows the rigid upper part to be manufactured with standard precision tools while the softer retention means can be molded with greater tolerance, reducing overall manufacturing complexity and cost.
Solution Approach 2:
The mounting channel is formed as a composite structure with the upper part made from a harder material and the second retention means made from a softer material. This composite approach allows each component to be optimized for its specific function and manufactured with appropriate tolerances using suitable tools, reducing the need for expensive high-precision equipment.
3Reliability
If the second retention means are made rigid, then secure retention of the longitudinal strip is achieved, but the spoiler cannot deform to allow bending of the retention means
Solution Approach 1:
The mounting channel exhibits local quality variation where the upper part maintains high rigidity for structural support while the second retention means has localized softness for deformability during insertion. After insertion, the retention means provide rigid retention. This local differentiation of material properties resolves the contradiction between rigidity for retention and flexibility for mounting.
Solution Approach 2:
The second retention means are made from material with different physical parameters (softer) than the upper part, allowing them to change their effective rigidity parameter during the mounting process. During insertion, they deform easily; during operation, they provide stable, rigid retention. This parameter change enables both deformability and reliable retention.
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 a cost-effective, one-piece product with improved retention and reduced wear, enabling secure mounting and movement of the wiper blade without deformation, suitable for various vehicles.
Implementation Method 1
said spoiler is made of a softer material than said second retention means to allow said bending
Implementation Method 2
said second retention means are semi-rigid. This semi-rigid material of said second retention means ensures that on the one hand a bending of said second retention means in lateral and outward direction is made possible upon mounting of said longitudinal strip into said longitudinal groove, and on the other hand a reliable and solid retention of said longitudinal strip in said longitudinal groove as defined by said second retention means is made possible
Implementation Method 3
In said bended position said hooks firmly grip said longitudinal strip, thereby avoiding any longitudinal, lateral or transversal movement of said longitudinal strip in said longitudinal groove
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A windscreen wiper device comprising an elastic, elongated carrier element, as well as an elongated wiper blade (2) to be placed in abutment with a windscreen to be wiped, said wiper blade (2) comprising an elongated upper part (3) and an elongated lower wiping part (4) of a flexible material, wherein said upper part (3) is provided with first retention means (12) for retaining said lower wiping part (4), as well as with second retention means (17) for retaining a longitudinal strip (6) of said carrier element, said second retention means (17) defining a longitudinal groove (5) for inserting said longitudinal strip (6) therein, which windscreen wiper device comprises a connecting device (8) for an oscillating arm, and wherein said oscillating arm is pivotally connected to said connecting device (8) about a pivot axis near one end thereof, with the special feature that said second retention means (17) are allowed to bend laterally outwardly upon insertion of said longitudinal strip (6) into said longitudinal groove (5), and that said longitudinal strip (6) is confined inside said longitudinal groove (5) upon mounting of said connecting device and/or connecting pieces closing outer ends of said longitudinal groove.