Inkjet Head Timing Control via Nip-Section Mark Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Ink-jet recording apparatuses face challenges in achieving high accuracy in adjusting ink jetting timings due to variations in ink jetting speeds and gaps between the recording head and medium, exacerbated by ambient humidity causing undulation in recording media, leading to inconsistent landing positions during two-way printing.

Innovation Solution

The apparatus incorporates a scanning mechanism, transport mechanism with nip sections, and a controller to form a pattern on areas with minimal undulation, specifically overlapping with nip sections for stable gaps and outer areas for reduced floating, allowing precise adjustment of ink jetting timings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If ink jetting timing is adjusted based on theoretical timing obtained by scanning speed and flying time, then the ink jetting process is simple, but the landing position deviation between forward scan and backward scan increases

Engineering Contradiction:

Improveink jetting timing controlVSAvoidlanding position accuracy

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent replaces the mechanical timing adjustment method with an optical detection method. Instead of physically adjusting the ink jetting timing based on theoretical calculations, the system uses a mark detection mechanism to optically measure the actual landing position deviation and automatically calculates the required timing correction, thereby improving landing position accuracy without significantly increasing system complexity

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent implements a feedback mechanism where the actual landing positions of marks formed during forward and backward scans are detected and compared. The detected position deviation is fed back to automatically adjust the ink jetting timing, creating a closed-loop control system that continuously optimizes landing position accuracy based on actual performance

Inventive Principle:

Principle #23Feedback

2Area of stationary object

If pattern formation is performed on recording medium areas not overlapping with nip sections, then the pattern formation area is larger, but the recording medium undulation increases due to ambient humidity

Engineering Contradiction:

Improvepattern formation areaVSAvoidrecording medium flatness

Core Design Contradiction:

Area of stationary objectVSStability of the object's composition

Solution Approach 1:

The patent applies the local quality principle by selectively forming patterns only in specific regions of the recording medium that overlap with nip sections. These regions have locally different properties (reduced undulation, better flatness) compared to other areas, making them suitable for precise mark formation and detection despite limiting the overall pattern formation area

Inventive Principle:

Principle #3Local quality

3Stability of the object's composition

If pattern formation is performed on recording medium areas overlapping with nip sections, then the recording medium flatness is improved, but the pattern formation area is reduced

Engineering Contradiction:

Improverecording medium flatnessVSAvoidpattern formation area

Core Design Contradiction:

Stability of the object's compositionVSArea of stationary object

Solution Approach 1:

Inventive Principle:

Principle #3Local quality

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 enables high-accuracy adjustment of ink jetting timings across various recording media, minimizing positional deviations and reducing the impact of ambient humidity, thus ensuring consistent printing quality.

Implementation Method 1

After the ink is jetted from each nozzle and before the jetted ink lands on the recording medium, the ink flies also in the scanning direction by the inertia caused by the movement of the recording head

Methodology Applied

Scientific EffectInertia: Inertia

Data Source

PatentUS8733870B2Ink-jet recording apparatus

Publication Date: 2014.05.27 BROTHER KOGYO KK

AI summary

There is provided an ink jet recording apparatus including an ink jet head; a scanning mechanism for scanning the ink-jet head; a transport mechanism including nip sections for nipping a recording medium; and a controller including a pattern forming mechanism, which controls the ink jet head to form a pattern including a mark for detecting a deviation between a landing position in a forward scanning and a landing position in a backward scanning; wherein the pattern forming mechanism controls the ink jet head to form a part of the mark on the recording medium in one of an area which overlaps in the transport direction with one of the nip sections and areas which are placed at outside positions of the nip sections nipping the recording medium at outermost positions in the scanning direction.