Porous Chuck Table Structure for Large-Workpiece Suction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional chuck tables with metal frames are heavy, costly, and difficult to polish, and require complex fluid passages for suction, making them inefficient for holding large workpieces and increasing the load on moving units.

Innovation Solution

A chuck table formed from a porous material without a metal frame, where fluid passages for suction are provided only by the pores in the material, allowing for lighter construction, easier polishing, and reduced complexity in suction passage design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a metal frame with porous plate is used to make a chuck table, then the structural strength and stability are improved, but the weight increases and the cost increases

Engineering Contradiction:
Improvestructural strengthVSAvoidchuck table weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The patent merges the frame structure and porous plate into a single integrated porous body. The porous material forms both the structural framework and the suction functionality in one component, eliminating the need for separate metal frame and porous plate assemblies, thereby reducing weight while maintaining structural integrity

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent uses a porous material that provides both structural support and suction functionality. The porous body serves as the entire chuck table structure, utilizing the porous material's inherent strength-to-weight ratio to achieve lightweight construction without sacrificing structural strength

Inventive Principle:
Principle #31Porous materials

2Strength

If a metal frame with porous plate is used to make a chuck table, then the structural strength is improved, but the manufacturing complexity and cost increase

Engineering Contradiction:
Improvestructural strengthVSAvoidframe and porous plate assembly complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent combines multiple components (frame, porous plate, adhesive layers, sealing structures) into a single integrated porous body. This merging eliminates the complexity of assembling multiple parts and reduces manufacturing steps, while the porous material itself provides the necessary structural strength

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts the frame structure from the traditional frame-and-plate design and integrates it directly into the porous material itself. The porous body assumes both structural and functional roles, simplifying the overall device complexity

Inventive Principle:
Principle #2Taking out (Extraction)

3Manufacturing precision

If the upper surfaces of the porous plate and frame are polished to lie flush, then the surface flatness is improved, but residual stresses are produced and the porous plate may deform

Engineering Contradiction:
Improvesurface flatnessVSAvoidporous plate stability
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent eliminates the separate frame component that requires polishing to match the porous plate surface. By making the porous body itself the entire chuck table structure, there is no interface between frame and plate surfaces, thus removing the polishing step that causes residual stresses and deformation

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent merges the frame and porous plate into one integrated porous body, eliminating the interface between two separate surfaces. This eliminates the need for flush polishing operations that generate residual stresses and potential deformation

Inventive Principle:
Principle #5Merging (Combining)

4Area of stationary object

If a large-diameter chuck table is fabricated to hold large workpieces, then the workpiece holding capability is improved, but the weight increases and the load on moving units increases

Engineering Contradiction:
Improvechuck table areaVSAvoidchuck table weight
Core Design Contradiction:
Area of stationary objectVSWeight of moving object

Solution Approach 1:

The patent utilizes porous materials with high strength-to-weight ratios to create large-diameter chuck tables. The porous structure provides sufficient mechanical strength for large areas while maintaining low weight, enabling large workpiece holding capability without proportionally increasing weight

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The porous material's cellular structure provides structural strength through its segmented pore architecture. This internal segmentation allows the material to span large distances while remaining lightweight, as the porous structure distributes loads efficiently across the large area

Inventive Principle:
Principle #1Segmentation

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 porous chuck table is lighter, easier to polish, and reduces the load on moving units, enabling efficient handling of large workpieces with improved suction performance and reduced costs.

Implementation Method 1

a porous material having pores; Fluid passages defined in the chuck table for allowing a negative pressure transmitted from the support base to act on the holding surface are provided only by the pores in the porous material

Methodology Applied
Scientific EffectPorosity: Porosity

Data Source

PatentEP3795288B1Chuck table and method of manufacturing chuck table
Publication Date: 2024.02.21 DISCO CORP
  • EP3795288B1 patent drawingFigure 1
  • EP3795288B1 patent drawingFigure 2A~2B
  • EP3795288B1 patent drawingFigure 3

AI summary

A processing apparatus includes a chuck table for holding a plate-shaped workpiece under suction on a holding surface thereof, a processing unit for processing the workpiece held on the holding surface of the chuck table, and a moving unit for moving a support base supporting the chuck table thereon in a processing-feed direction. The chuck table is formed from a porous material having pores, and has the holding surface and a mountable assembly positioned opposite the holding surface and mountable on an upper surface of the support base. Fluid passages defined in the chuck table for allowing a negative pressure transmitted from the support base to act on the holding surface are provided only by the pores in the porous material.