Dynamic Leading Edge Margin Adjustment for Cut Sheet Print Omissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image omissions or white streaks occur during image printing on cut sheets due to variations in sheet length caused by cutting tolerance, environment, and other factors, leading to inadequate margin allocation.
Innovation Solution
The printing apparatus adjusts the leading edge margin length dynamically based on the actual sheet length to ensure the entire image length is printed by setting a conveyance limit at the trailing edge position, preventing image omissions and reducing the risk of white streaks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a fixed leading edge margin length is used for printing, then the printing process is simple and fast, but image omissions or white streaks occur when sheet length varies
Solution Approach 1:
The patent applies dynamics by making the leading edge margin length variable rather than fixed. The control unit dynamically adjusts the leading edge margin based on the detected actual sheet length, allowing the printing system to adapt to different sheet dimensions and prevent image omissions or white streaks while maintaining printing efficiency
Solution Approach 2:
The patent changes the parameter of leading edge margin length from a constant value to a variable that is adjusted according to the detected sheet length. The control unit modifies this parameter based on the difference between the standard sheet length and the actual measured length, ensuring complete image printing across varying sheet conditions
2Manufacturing precision
If the leading edge margin length is increased to accommodate sheet length variations, then image omissions are prevented, but the printable area is reduced
Solution Approach 1:
The patent makes the leading edge margin length dynamic rather than statically increased. The margin is adjusted in real-time based on the detected sheet length, ensuring that the margin is only increased when necessary to prevent image omissions, thereby maximizing the printable area for each specific sheet
Solution Approach 2:
The control unit adjusts the leading edge margin parameter based on the detected sheet length variation. When the actual sheet length is shorter than the standard length, the margin is reduced accordingly, preserving maximum printable area while still preventing image omissions
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A conveyance unit (31, 402) of an image printing apparatus (101) includes a conveyance member (31) configured to nip and convey the print medium (201) and disposed upstream of the print head (3) in the conveyance direction but does not include a conveyance member configured to nip and convey the print medium and disposed downstream of the print head in the conveyance direction. In a case where a trailing edge margin length indicated by the trailing edge margin information is shorter than a first length, a control unit (400) of the image printing apparatus controls the print head and the conveyance unit such that at least one scan of the print head for printing the image is performed after a trailing edge of the print medium in the conveyance direction passes by the conveyance member disposed upstream of the print head.