Polyurethane Refrigerator Insulation With Smaller Foam Cells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The insulation efficiency of cooling devices, such as refrigerators and freezers, decreases with larger cell sizes in insulation materials, leading to increased energy consumption and reduced efficiency.
Innovation Solution
The use of pulverized waste rigid polyurethane additive with a reduced particle size, mixed with polyol and pentane, and reacted with isocyanate to produce a polyurethane insulation material with decreased cell size, enhancing thermal insulation and reducing thermal conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the cell size of the insulation material is increased, then the manufacturing process becomes simpler and the material strength increases, but the thermal conductivity increases and insulation efficiency decreases
Solution Approach 1:
The patent changes the physical-chemical parameters of the insulation material by incorporating pulverized rigid polyurethane with specific particle sizes (0.2-100 microns) and controlling the cell size distribution (average cell size of 0.5-2.0 mm). This parameter optimization reduces thermal conductivity while maintaining structural integrity, resolving the contradiction between strength and insulation efficiency.
Solution Approach 2:
The patent creates a composite insulation material by combining pulverized rigid polyurethane particles with polyol and pentane, then reacting with isocyanate. This composite structure integrates the benefits of recycled polyurethane (strength) with the foam matrix (insulation), achieving both mechanical strength and low thermal conductivity (k-value of 0.020-0.040 W/m·K).
2Device complexity
If the cell size of the insulation material is increased, then the manufacturing complexity decreases, but the insulation efficiency and cooling device performance deteriorate
Solution Approach 1:
The patent optimizes the cell size parameter to an average of 0.5-2.0 mm with controlled distribution, which balances manufacturing feasibility with insulation performance. This parameter control ensures uniform expansion and curing while achieving the desired thermal insulation properties without excessive manufacturing complexity.
Solution Approach 2:
The patent recovers and reuses pulverized rigid polyurethane from waste materials, transforming what would be discarded into a valuable additive. This recovery process creates a standardized material input with controlled particle sizes, simplifying the manufacturing process while improving insulation efficiency through the nucleation effect on cell formation.
3Loss of energy
If waste polyurethane is recycled and pulverized to reduce particle size, then the thermal conductivity decreases and insulation efficiency increases, but the manufacturing process complexity increases
Solution Approach 1:
The patent specifies precise particle size parameters for the pulverized polyurethane (0.2-100 microns) and controls the resulting cell size distribution (average 0.5-2.0 mm). These parameter specifications optimize the balance between thermal performance (reduced conductivity) and manufacturing complexity, ensuring the pulverization process remains practical while achieving the desired insulation effects.
Solution Approach 2:
The patent implements a recovery system that collects, pulverizes, and reuses rigid polyurethane from waste sources. This closed-loop approach transforms waste material into a functional additive, reducing the need for virgin materials and energy-intensive production while improving insulation performance through the controlled incorporation of fine particles that reduce cell size and thermal conductivity.
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 increases the insulation efficiency of cooling devices, reduces energy consumption, and promotes environmentally friendly and cost-effective production by recycling waste materials.
Implementation Method 1
the insulation material comprises pulverized rigid polyurethane in a ratio between 0.5% and 25% by weight that serves as a heterogeneous nucleation agent
Implementation Method 2
By adding isocyanate into the mixture formed after mixing the pulverized waste polyurethane with the polyol and pentane, the curing reaction starts
Implementation Method 3
an insulation material that is generally closed-cell rigid polyurethane is filled between the inner and outer walls of the body in order to provide heat insulation between the inner volume and the outer environment
Data Source
Figure 1
Figure 2
AI summary
The present invention relates to a cooling device (1) with increased insulation effectiveness, comprising a body (2) that has an inner wall (3), an outer wall (4), an insulation volume (5) between the inner wall (3) and the outer wall (4) and an insulation material (6) filled into the insulation volume (5).