Composite Wiper Arm Torque Transmission Aerodynamic Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional windscreen wiper arms made of metal are expensive to manufacture and cannot be easily adapted to vehicle design or optimal aerodynamic configurations due to complex production processes and rigidity requirements.
Innovation Solution
A wiper arm design featuring a rigid area for torque transmission and an elastic area for blade pressing, both encased in plastic using a two-component injection molding process, allowing for cost-effective production and aerodynamic adaptation, with inserts made from materials like polybutylene terephthalate and fiber-reinforced plastics for enhanced strength and flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If metal is used to manufacture wiper arms to support high strength against aerodynamic forces, then strength and rigidity are improved, but manufacturing cost increases due to complex stamping, bending, pressing and assembly processes
Solution Approach 1:
The wiper arm combines metal inserts (for strength and rigidity) with plastic coverings (for aerodynamic shaping and cost-effective manufacturing). This composite structure allows the metal components to provide mechanical strength while the plastic components enable complex aerodynamic shapes to be formed through injection molding, avoiding complex metal forming processes and reducing manufacturing costs.
2Strength
If metal wiper arms are manufactured using traditional processes, then structural strength is achieved, but adaptability to vehicle design and aerodynamic configuration is reduced
Solution Approach 1:
The combination of metal inserts with plastic coverings enables the wiper arm to achieve both structural strength and design flexibility. The plastic components can be easily molded into various aerodynamic configurations and vehicle-specific designs, while the metal inserts maintain the necessary mechanical strength, thus resolving the contradiction between strength and adaptability.
Solution Approach 2:
The wiper arm applies different materials to different regions: metal inserts are placed in areas requiring high strength and rigidity, while plastic coverings are used in areas requiring aerodynamic shaping and design flexibility. This local differentiation of material properties allows the structure to simultaneously achieve strength and adaptability.
3Power
If a rigid wiper arm structure is used to transmit torque effectively, then torque transmission is improved, but the ability to press the wiper blade against the windshield is reduced
Solution Approach 1:
The wiper arm features a rigid metal insert area for effective torque transmission from the wiper drive, while the elastic wiper arm area with different material properties provides the necessary flexibility and pressing force against the windshield. This local differentiation of rigidity allows both torque transmission and blade pressing functions to be optimized simultaneously.
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 enables easy and inexpensive manufacturing while improving aerodynamic behavior and durability, reducing production steps and material usage, and providing effective wind deflection for enhanced wiper blade contact.
Implementation Method 1
the first plastic cover having a different elasticity than the second plastic cover
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a wiper arm (1) for a windshield wiping device (3) of a motor vehicle, comprising a first receiving portion 9 for fixing the wiper arm (1) on the windshield wiping device (3) and a second receiving portion (10) for fixing a wiper blade (2). A rigid wiper arm region (13) that adjoins the first receiving portion (9) and an elastic wiper arm region (14) that adjoins the second receiving portion (10) lie between the first and second receiving portions (9, 10). The rigid wiper arm region (13) is designed to transmit a torque that acts about a rotational axis (24) of the wiper arm (1) and the elastic wiper arm region (14) is designed to provide a force to push the wiper blade (2) onto a windshield. The rigid wiper arm region (13) has a first insert (15) and the elastic wiper arm region (14) has a second insert (16), said first insert (15) being surrounded by a first plastic casing (17) and said second insert (16) being surrounded by a second plastic casing (18). The first plastic casing (17) has an elasticity that is different from the second plastic casing (18).