Inverted Injection Molding for Window Lifting Carrier Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing production methods for window lifting device carrier elements face challenges such as suboptimal adhesion between dissimilar materials, burr formation, and increased assembly complexity due to the sequential molding of materials with different melting points, leading to inefficiencies and noise generation.
Innovation Solution
Implementing an 'inverted injection-molding method' where a body from a material melting at a higher temperature is molded onto a body from a material melting at a lower temperature, eliminating the need for additional linking features and reducing burr formation by molding the main body last, which simplifies tool construction and avoids excessive injection pressures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a body from material melting at lower temperature is molded first, then a body from material melting at higher temperature is molded onto it, then adhesion between components is improved, but burr formation increases and injection pressure becomes excessive
Solution Approach 1:
The patent inverts the conventional molding sequence by molding the body from higher melting point material first, then molding the body from lower melting point material onto it. This reversal eliminates burr formation and excessive injection pressure while maintaining strong adhesion between components, as the higher melting point material provides a stable base that prevents material displacement during the second molding step.
2Strength
If additional linking features are added to ensure adequate strength between sequentially molded bodies, then connection strength is improved, but device complexity increases
Solution Approach 1:
The patent merges the connection function into the molding process itself by ensuring adequate surface area and contact between the sequentially molded bodies. The inversion of the molding sequence allows the materials to bond directly through molecular adhesion during cooling, eliminating the need for separate linking features such as ribs, clips, or mechanical fasteners, thus reducing structural complexity while maintaining connection strength.
3Manufacturing precision
If sealing edges are added to prevent excessive injection, then injection precision is improved, but closing force requirement increases
Solution Approach 1:
By inverting the molding sequence and molding the higher melting point material first, the patent creates a stable base structure that contains the subsequent lower melting point material. This eliminates the need for complex sealing edges and reduces closing force requirements, as the higher melting point material's structural integrity prevents material displacement and burr formation without requiring additional sealing mechanisms.
4Ease of manufacture
If multiple bodies are molded separately and then assembled, then manufacturing flexibility is improved, but assembly effort increases
Solution Approach 1:
The patent applies preliminary action by molding the first body (higher melting point material) in advance with appropriate surface characteristics and geometry that facilitate direct bonding. The inversion of the sequence allows the second material to be molded directly onto the first body in a continuous process, creating an integrated component that eliminates subsequent assembly steps while maintaining the manufacturing flexibility to produce different configurations.
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 approach enhances adhesion between components, reduces burr formation, and simplifies the injection-molding process, resulting in a carrier element with improved assembly efficiency and reduced noise during operation.
Implementation Method 1
a body from a material melting at a lower temperature is molded before a body from a material melting at a higher temperature
Implementation Method 2
materials having dissimilar melting points
Data Source
AI summary
A method for producing a carrier element for a window lifting device in which adjustment of a glass is performed by means of a traction means, the carrier element being displaceable along a guide rail of the window lifting device and being connected to the traction means, is provided. The completed carrier element has at least two interconnected bodies which are produced from dissimilar materials having dissimilar melting points, and the carrier element having the at least two bodies is produced by a multicomponent injection-molding method. In the production of the carrier element by the multicomponent injection-molding method a body from a material melting at a lower temperature is molded before a body from a material melting at a higher temperature, and the body from the material melting at a higher temperature is molded to the body from the material melting at a lower temperature.