Print Apparatus Duplex Cutting Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing print apparatuses face challenges in performing duplex printing at high speed and quality while maintaining high positional accuracy for cutting continuous sheets, as they require multiple stops and can misidentify patterns, leading to inaccurate cutting and reduced print quality.
Innovation Solution
A print apparatus with separate reading units for patterns and cut marks, and dual cutters that minimize upstream impact, allowing for high-speed duplex printing and precise cutting by reading cut marks during a limited detection period to avoid misidentification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the sheet is continuously stopped twice to cut off the margin area, then the margin area is cut off, but the impact is transmitted twice to the sheet upstream side, affecting reading accuracy and print accuracy
Solution Approach 1:
The patent divides the cutting operation into two independent cutters (first cutter and second cutter) that operate at different positions. The first cutter is positioned to cut before the margin area, and the second cutter is positioned to cut after the margin area. This segmentation allows the sheet to be stopped only once at the first cutter position, preventing repeated impacts on the upstream side while still achieving complete margin removal.
2Measurement precision
If the cut position sensor distinguishes the original image from the cut mark, then correct detection is achieved, but false recognition occurs when a pattern similar to the cut mark is accidentally included in the original image
Solution Approach 1:
The patent introduces a dedicated cut mark sensor that serves as an intermediary detection device. This sensor is specifically designed to detect cut marks with high precision while being positioned and configured to avoid misidentification. The cut mark sensor works in conjunction with the image sensor, providing a specialized detection mechanism that distinguishes true cut marks from similar patterns in the original image.
3Productivity
If duplex printing is performed at high speed, then productivity is improved, but the sheet conveyance must be precisely controlled to maintain print quality and cutting accuracy
Solution Approach 1:
The patent implements dynamic control of the sheet conveyance system, allowing the conveyance speed to be adjusted based on the operational phase. During duplex printing, the system can operate at high speed, but when cutting is required, the conveyance is precisely controlled to stop at the appropriate position. The dual cutter system enables this dynamic control by positioning cutters at specific locations where the sheet can be stopped without affecting upstream reading operations.
Data Source
AI summary
A first reading unit that reads a pattern or an image formed on a sheet by a print unit for recognizing a print unit state, a second reading unit that reads a cut mark formed on the sheet on a downstream thereof, a cutter that cuts the sheet on a downstream thereof, and a reverse unit that reverses the sheet fed to the print unit again are provided. In duplex printing, the sheet where images are sequentially printed on a first surface is led to the reverse unit, the front and rear faces are reversed, and the sheet is fed to the print unit again. The sheet where images and cut marks are sequentially printed on a second surface is cut by the cutter for each piece and discharged. The sheet is cut on the basis of a reading of the cut mark by the second reading unit.