Polymer Appliance Parts With Cast-In Strip Conductors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The manufacture of household appliance component parts with integrated electric strip conductors is cumbersome, time-consuming, and expensive due to the complexity of existing methods involving polymer and metal combinations.

Innovation Solution

A process where a basic polymer body with cavities and channels is injection molded, followed by the introduction of a liquid metal composition that solidifies within these cavities, forming a strip conductor without a polymeric sheath, with the metal composition's melting point ranging from 100 to 130°C, allowing direct contact and improved adhesion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional methods of forming strip conductors on polymer bodies are used (punching metal sheets, placing, or extrusion coating), then electrical connectivity is achieved, but the manufacturing process becomes cumbersome, time-consuming, and expensive

Engineering Contradiction:
Improveelectrical connectivityVSAvoidmanufacturing efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent combines the polymer injection molding process with the metal strip conductor formation process into a single integrated manufacturing step. The metal composition is introduced directly into the injection molding cavity during polymer injection, eliminating the need for separate punching, placing, or extrusion coating operations. This merging of processes directly addresses the productivity issue while maintaining electrical connectivity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces the metal composition into the polymer melt before injection into the mold cavity, or directly into the cavity during injection. This preliminary positioning of the metal strip conductor within the polymer body eliminates subsequent assembly steps and ensures proper electrical connectivity is built-in during the molding process itself, thereby improving manufacturing efficiency.

Inventive Principle:
Principle #10Preliminary action

2Stability of the object's composition

If multiple separate steps are used to manufacture hybrid polymer-metal component parts, then proper integration is achieved, but the process becomes complex and costly

Engineering Contradiction:
Improvepolymer-metal integrationVSAvoidmanufacturing process complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent merges multiple manufacturing operations (polymer molding, metal strip formation, and assembly) into a single injection molding process. The metal composition is introduced and formed within the polymer matrix during the injection molding cycle itself, creating a stable integrated hybrid component without requiring separate processing steps or complex assembly procedures.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The injection molding machine is made multi-functional by enabling it to handle both polymer material and metal composition in a single process cycle. The system can inject polymer melt, introduce metal composition (either pre-mixed or separately), and form the integrated hybrid component all through the same equipment and process parameters, thereby reducing device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Strength

If metal composition with higher melting point is used, then structural strength is improved, but direct contact with polymer body during injection molding becomes problematic

Engineering Contradiction:
Improvestructural strengthVSAvoidprocessing compatibility
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The patent changes the temperature parameter of the metal composition to be within the range of 100-130°C, which is below the decomposition temperature of typical polymers used in injection molding. This parameter change allows the metal to remain in a manageable state during polymer injection while still achieving proper integration and adhesion, thereby improving ease of manufacture without sacrificing structural strength.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent utilizes the phase transition properties of the metal composition by introducing it in a liquid or semi-liquid state at controlled temperatures (100-130°C). The metal composition transitions from liquid to solid form within the polymer matrix during cooling, creating strong adhesion and structural integrity. This phase transition approach enables proper integration while maintaining processing compatibility with polymer injection molding.

Inventive Principle:
Principle #36Phase transitions

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 method simplifies and accelerates the production of household appliance components, reducing costs while ensuring effective electrical connectivity and durability through direct polymer-metal contact.

Implementation Method 1

the component part is obtainable by injection molding wherein the organic polymer is first of all injection molded to provide a basic polymer body with cavities and/or channels

Methodology Applied
Scientific EffectInjection molding:

Implementation Method 2

into thereafter the metal composition is introduced in liquid form

Methodology Applied
Scientific EffectSolidification: Freezing

Implementation Method 3

wherein the softening point of the organic polymer is above the melting point of the metal composition

Methodology Applied
Scientific EffectPhase change: Phase Change

Implementation Method 4

the basic polymer body is in direct contact with the metal composition

Methodology Applied
Scientific EffectAdhesion: Adhesive

Data Source

PatentEP3450130B1Household appliance with a component part containing a basic polymer body and a metal composition and process for its manufacture
Publication Date: 2021.11.10 BSH HAUSGERATE GMBH
  • EP3450130B1 patent drawingFigure 1~2

AI summary

The invention relates to a household appliance with a component part 1 that contains a basic polymer body 2 containing an organic polymer and a metal composition forming a strip conductor 3 therein, wherein the basic polymer body 2 is in direct contact with the metal composition and wherein the softening point of the organic polymer is above the melting point of the metal composition. The invention relates moreover to a process for the manufacture of a household appliance.