Honeycomb Forming Die Flow Control for Thin-Wall Extrusion

Solution Overview

Problem

The reduction of cell wall thickness in honeycomb structures for exhaust gas purification catalysts leads to difficulties in achieving uniform material supply and extrusion speed, resulting in twists and bends, which limits weight reduction and increases the risk of deformation, thereby decreasing productivity and molding accuracy.

Innovation Solution

A honeycomb structure forming die with a material supply portion and slit portion, where the material supply holes are positioned at grid points and communicate with a slit having a grid shape, and include throttle holes and guide holes to ensure uniform material distribution and reduce deformation, manufactured using a 3D printing method that melts and solidifies metal powder with a laser beam.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If cell wall thickness is reduced to achieve weight reduction, then weight decreases, but molding precision deteriorates due to twists and bends

Engineering Contradiction:

Improveweight of honeycomb structureVSAvoidmolding precision

Core Design Contradiction:

Weight of moving objectVSManufacturing precision

Solution Approach 1:

The patent applies local quality by varying the diameter of material supply holes along their length. The holes have a larger diameter at the material supply surface and a smaller diameter at the slit end, creating a gradient structure that optimizes material flow distribution to different regions of the slit, thereby preventing deformation even with thin cell walls

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the geometric parameters of the material supply holes by implementing a diameter gradient along the hole length. This parameter variation ensures uniform material supply to different portions of the slit, maintaining molding precision while enabling weight reduction through thinner cell walls

Inventive Principle:

Principle #35Parameter changes

2Weight of moving object

If cell wall thickness is reduced to achieve weight reduction, then weight decreases, but productivity deteriorates due to lower molding speed

Engineering Contradiction:

Improveweight of honeycomb structureVSAvoidmolding speed

Core Design Contradiction:

Weight of moving objectVSProductivity

Solution Approach 1:

The patent applies local quality by varying the diameter of material supply holes along their length. The holes have a larger diameter at the material supply surface and a smaller diameter at the slit end, creating a gradient structure that optimizes material flow distribution to different regions of the slit, thereby preventing deformation even with thin cell walls

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the geometric parameters of the material supply holes by implementing a diameter gradient along the hole length. This parameter variation ensures uniform material supply to different portions of the slit, maintaining molding precision while enabling weight reduction through thinner cell walls

Inventive Principle:

Principle #35Parameter changes

3Manufacturing precision

If material supply uniformity is improved to prevent deformation, then molding precision increases, but device complexity increases

Engineering Contradiction:

Improvemolding precisionVSAvoiddie structure complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent changes the geometric parameters of the material supply holes by implementing a diameter gradient along the hole length. This parameter variation ensures uniform material supply to different portions of the slit, maintaining molding precision while enabling weight reduction through thinner cell walls

Inventive Principle:

Principle #35Parameter changes

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 configuration allows for increased molding speed and reduced deformation, enabling higher precision and productivity while maintaining the desired cell density and shape, thus overcoming the limitations of traditional die designs.

Implementation Method 1

applying a laser beam to the metal powder to melt and solidify the metal powder

Methodology Applied

Scientific EffectLaser heating: Laser

Data Source

PatentUS11059200B2Honeycomb structure forming die and method of manufacturing honeycomb structure forming die

Publication Date: 2021.07.13 DENSO CORP

AI summary

A die includes a die body, a material supply portion, and a slit portion. The material supply portion includes a material supply surface, and a material supply hole that extends in an extrusion direction from the material supply hole. The slit portion includes an extrusion surface that faces the material supply surface across the material supply hole, and a slit that has a grid shape, opens on the extrusion surface, and communicates with the material supply hole. The slit has a grid point. The material supply hole is provided at a position corresponding to the grid point and coaxially with the grid point. An end of the material supply hole in the extrusion direction includes a throttle hole whose diameter decreases toward the grid point, and a guide hole that extends outward from the throttle hole and guides a material to the slit including the grid point.