Squeegee Device Phase-Synchronized Control for Print Quality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Security printing machines face challenges in maintaining high print quality while minimizing wear and tear, and reducing maintenance and cleaning costs, particularly due to the risk of unwanted ink contamination on non-printing areas and counter-printing surfaces.
Innovation Solution
A squeegee device with a drive system that can be controlled to switch on and off based on the length and format of the printing material, synchronized with the machine phase, to precisely manage its position and movement, reducing unnecessary ink application and wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the squeegee remains continuously pressed against the screen printing stencil during the entire printing cycle, then continuous ink application ensures complete coverage, but unwanted ink contamination occurs on non-printing areas and counter-printing surfaces
Solution Approach 1:
The squeegee is activated periodically rather than continuously - it is pressed against the screen printing stencil only during the printing phase and lifted during the non-printing phase. This periodic on/off action eliminates unwanted ink contamination while maintaining complete ink coverage on the printing areas, directly resolving the contradiction between print quality and ink contamination.
2Manufacturing precision
If the squeegee is continuously active during printing, then consistent ink application maintains print quality, but wear and tear on the squeegee increases
Solution Approach 1:
The squeegee operates in periodic cycles of contact and separation from the screen printing stencil. By lifting the squeegee during non-printing phases, the duration of mechanical contact and associated wear is reduced, extending squeegee lifespan while maintaining print quality during active printing phases.
3Productivity
If the squeegee is continuously active, then printing can proceed without interruption, but maintenance and cleaning costs increase due to accumulated ink residue
Solution Approach 1:
The squeegee is lifted during non-printing phases, creating periodic intervals where no ink is applied. This reduces the accumulation of ink residue on the squeegee and screen printing stencil, thereby decreasing maintenance and cleaning costs while allowing printing to proceed continuously during active phases.
4Productivity
If the squeegee is lifted early to resume printing after pit passage, then productivity increases, but print quality may be compromised if timing is not precise
Solution Approach 1:
The squeegee positioning system uses feedback from the pit detection mechanism to determine the optimal timing for squeegee re-engagement. This feedback control ensures the squeegee is lifted and repositioned at the precise moment needed to resume printing without compromising quality, maximizing productivity while maintaining print standards.
Data Source
Figure 1
Figure 2a~2b
Figure 3~4
AI summary
The invention relates to a squeegee device for a printing press which prints a printing material (02) at at least one printing point (06, 07) in accordance with a screen printing process, comprising a screen printing screen (31; 32), a squeegee (34) which is set against the screen printing screen (31; 32) in a thrown-on position ("ON") and/or can be set against the screen printing screen (31; 32) into a thrown-on position ("ON"), a bearing device (56, 57, 58) which makes a throwing-on and throwing-off movement possible between the thrown-on position ("ON") of the squeegee (34) and a thrown-off position ("OFF"), and a drive device (39, 41, 48), by way of which the squeegee (34) can be set against the screen printing screen (31; 32) and can be set away from the latter during operation in a manner which is correlated to a press or printing material phase position, wherein the drive device (39, 41, 48) is set up to bring about and/or to make possible throwing on and throwing off of the squeegee (34) in sequences which differ from one another with different phase positions and/or phase lengths in relation to the length of the screen printing screen (31; 32).