Image Forming Controller Timing Correction for Overlapping Data
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In image forming apparatuses, the transmission timing of control data for different colors can overlap when a separator sheet of a different size is inserted during continuous printing, leading to image defects due to incomplete data transmission, which existing methods attempt to address by increasing communication speed or throughput, but these solutions either increase costs or decrease performance.
Innovation Solution
The image forming apparatus includes a controller that adjusts the timing of magnification and position correction data for each color based on the distance between transfer positions, ensuring that data is transmitted correctly by outputting correction data for one color before the next, even if the previous data transmission is incomplete, using a common signal line to prevent overlapping transmission periods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the communication speed of serial communication is increased to avoid overlapping transmission timing, then the transmission reliability of control data is improved, but the cost increases
Solution Approach 1:
The patent applies preliminary action by calculating and determining the transmission timing of control data for each color in advance, before actual transmission occurs. The timing determination unit calculates the transmission timing based on the sum of image data transmission time and communication time, and sets the timing so that transmissions do not overlap. This advance planning prevents overlapping without requiring increased communication speed, thereby maintaining cost-effectiveness while ensuring transmission reliability.
2Reliability
If the interval between trailing edge of previous image and leading edge of next image is expanded to prevent overlapping, then the transmission reliability is improved, but the throughput decreases
Solution Approach 1:
The patent applies dynamics by making the transmission timing adjustable and color-specific rather than fixed. The timing determination unit dynamically calculates the optimal transmission timing for each color based on image data transmission time and communication time, allowing the system to adapt to different printing conditions and color sequences. This dynamic timing adjustment ensures reliable transmission without requiring excessive intervals that would reduce throughput.
3Productivity
If the rotational speed of photoconductive drum is increased to maintain throughput with larger intervals, then the throughput is maintained, but the cost increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating transmission timing for each color based on the actual image data transmission time and communication time. This advance timing determination allows the system to use the existing rotational speed of the photoconductive drum while still preventing overlapping transmissions. By optimizing the timing schedule rather than increasing speed, the system maintains throughput without the additional costs associated with higher rotational speeds.
4Reliability
If the transmission timing of control data is delayed to avoid overlapping, then the transmission reliability is improved, but the image formation timing accuracy deteriorates
Solution Approach 1:
The patent applies local quality by implementing color-specific transmission timing rather than a uniform delay for all colors. The timing determination unit calculates and sets individual transmission timings for each color (Y, M, C, K) based on their respective image data transmission times and communication times. This localized timing optimization ensures that each color's control data is transmitted at the precise moment needed for accurate image formation, maintaining timing accuracy while preventing overlaps through targeted rather than blanket delays.
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 prevents image defects by ensuring complete data transmission for each color, maintaining throughput, and reducing costs associated with increased communication speed or motor power, thereby enhancing the reliability and efficiency of the image forming process.
Implementation Method 1
a first electrostatic latent image forming unit including a first photoconductor rotatingly driven, a first exposure unit configured to expose the first photoconductor
Implementation Method 2
a first development unit configured to develop, with toner of a first color, a first electrostatic latent image formed on the first photoconductor
Implementation Method 3
a transfer unit formed as an endless transfer belt rotatingly driven, where the transfer unit is configured to transfer the toner image on the first photoconductor and the toner image on the second photoconductor to a print medium
Data Source
AI summary
If a timing of outputting magnification correction data for first image data to form first electrostatic latent image for an (n+1)th print medium overlaps a timing of outputting magnification correction data for second image data to form an electrostatic latent image for an nth print medium having a size smaller than the (n+1)th print medium in a conveyance direction of the print medium, a CPU outputs the magnification correction data for the second image data to form the second electrostatic latent image for the nth print medium before the magnification correction data for the first image data to form the first electrostatic latent image for the (n+1)th print medium is output and outputs the magnification correction data for the (n+1)th print medium after a magnification correction process performed by a second data processing unit based on the magnification correction data for the nth print medium is completed.