Substrate Transport System for Inkjet Printing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing substrate transport systems in printing machines face challenges such as deformation of large substrates, accidental suction of ink by suction belts, difficulty in adjusting print heads for non-flat substrates, and fixed print pitch, which limits the use of substrates of varying sizes and thicknesses.

Innovation Solution

A substrate transport system using a fixed suction sole and mobile gripping means with independent movement, controlled by computer means, to tension and move substrates of varying lengths and sizes, allowing for variable print pitch and precise positioning during printing and drying.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If suction belts are used to transport substrates, then substrates can be held against moving belts, but large substrates deform due to air currents and pressure gradients

Engineering Contradiction:
Improvesubstrate transport stabilityVSAvoidprinting accuracy
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent extracts the harmful air currents and pressure gradients from the transport system by replacing suction belts with a flat conveyor belt and separate gripping mechanisms. This eliminates the cause of substrate deformation while maintaining transport functionality.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The transport system is segmented into separate functions: a flat conveyor belt for movement and independent gripping means for substrate control. This segmentation allows each component to perform its function without causing substrate deformation.

Inventive Principle:
Principle #1Segmentation

2Productivity

If suction belts are used to transport substrates, then substrates can be transported, but ink is accidentally suctioned by the belts causing print heads to lose prime

Engineering Contradiction:
Improvesubstrate transport capabilityVSAvoidprint head prime stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent removes the suction function from the transport belt, separating substrate transport from ink interaction. The flat conveyor belt transports substrates without creating negative pressure, eliminating ink suction incidents while maintaining transport efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of operation

If cylinders with multiple grippers are used to transport substrates, then substrates can be grasped by leading edge, but all inkjet printheads must be arranged orbitally around a large cylinder

Engineering Contradiction:
Improvesubstrate grasping capabilityVSAvoidprinthead arrangement complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

Instead of arranging printheads around a cylindrical transport path, the patent inverts the approach by using a flat conveyor belt with grippers that move independently. This allows traditional linear printhead arrangements while maintaining effective substrate control.

Inventive Principle:
Principle #13The other way round (Inversion)

4Force

If cylinders with multiple grippers are used to transport substrates, then substrates can be tensioned, but adjusting print head positions is difficult due to non-flat substrate surface

Engineering Contradiction:
Improvesubstrate tensionVSAvoidprint head position adjustment
Core Design Contradiction:
ForceVSEase of operation

Solution Approach 1:

The patent makes the gripper system dynamic with independently controllable front and rear grippers that can adjust their positions and timing. This dynamic control maintains substrate tension while keeping the substrate surface flat relative to printheads, eliminating adjustment difficulties.

Inventive Principle:
Principle #15Dynamics

5Manufacturing precision

If cylinders with multiple grippers are used to transport substrates, then substrates can be moved, but print pitch is fixed limiting printing speed for different substrate sizes

Engineering Contradiction:
Improveprint pitch controlVSAvoidprinting speed adaptability
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The patent implements dynamic control of gripper positioning and timing, allowing variable print pitch adjustment. The independently controllable grippers can adapt to different substrate sizes and printing speeds, eliminating the fixed pitch limitation while maintaining printing precision.

Inventive Principle:
Principle #15Dynamics

6Ease of operation

If chains or conveyors with grippers on flat path are used, then printhead placement is simplified, but print pitch remains fixed requiring stopping and adjustment for different substrate sizes

Engineering Contradiction:
Improveprinthead placementVSAvoidsubstrate size adaptability
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent adds dynamic control capabilities to the flat conveyor system, enabling variable print pitch and gripper positioning. This allows the system to adapt to different substrate sizes without stopping, maintaining simplified printhead placement while gaining versatility.

Inventive Principle:
Principle #15Dynamics

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 system minimizes the number of gripping means and motors, enables printing close to the input, and adapts to substrates of different sizes and thicknesses, improving printing accuracy and efficiency by maintaining substrates flat during transport and drying.

Implementation Method 1

a fixed suction base holding the substrate flat on the plate along the transport path

Methodology Applied
Scientific EffectSuction: Suction

Data Source

PatentEP3204235B1Device and method for transporting substrates in a printing machine
Publication Date: 2021.02.17 MGI DIGITAL TECH
  • EP3204235B1 patent drawingFigure 1~2
  • EP3204235B1 patent drawingFigure 3~4
  • EP3204235B1 patent drawingFigure 5

AI summary

The object of the present invention is to propose a novel device and a novel method to allow the transportation of substrates that can be printed precisely, suited to substrates of various types, sizes and thicknesses. Furthermore, the invention is suited to printing machines that involve no contact with the substrate, such as inkjet printing machines.