Scanner Motor Control for Pixel Alignment During Read Suspension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Reading apparatuses face issues with read-suspension events due to buffer memory capacity limitations and motor overheating, leading to potential misalignment and image quality issues when resuming document scanning.
Innovation Solution
The apparatus includes a control unit that monitors the relative position of the last read pixel using an encoder and decelerates the motor to stop at a predetermined position within the last read pixel, ensuring accurate resumption of scanning without misalignment by setting a stop position that accounts for overrun distances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the reading is temporarily suspended due to buffer memory capacity limitation or motor overheating, then the buffer memory capacity is preserved or the motor is protected, but misalignment occurs at the joint between read pixels before and after suspension
Solution Approach 1:
The control unit performs preliminary actions by monitoring the relative position of the last read pixel during normal operation and preparing the motor for controlled deceleration before suspension occurs. This ensures that when suspension is necessary, the system is already positioned to minimize alignment issues at resumption
Solution Approach 2:
The control unit continuously receives feedback from the encoder regarding the relative position of the document and image sensor. During suspension and resumption, this feedback enables real-time monitoring and adjustment of motor position to ensure the read position reaches the exact stop position within the last read pixel, preventing misalignment
2Temperature
If the motor is temporarily stopped during read-suspension event, then the motor overheating is prevented, but misalignment occurs at the joint between read pixels before and after suspension
Solution Approach 1:
The control unit performs preliminary positioning by monitoring the relative position during normal operation and preparing the motor for controlled deceleration before suspension. This ensures that when the motor stops due to overheating prevention, it does so at a controlled position that minimizes alignment issues
Solution Approach 2:
The encoder provides continuous feedback on motor position and document movement. During motor stop for temperature management, this feedback enables the control unit to monitor that the read position reaches the predetermined stop position within the last read pixel, ensuring accurate resumption without misalignment
3Loss of time
If the motor deceleration is not controlled during read-suspension event, then the response time to suspension event is reduced, but misalignment occurs at the joint between read pixels before and after suspension
Solution Approach 1:
The control unit performs preliminary monitoring of the relative position of the last read pixel during normal operation. When suspension is required, this pre-monitored information enables immediate controlled deceleration without unnecessary delays, while still ensuring the read position reaches the correct stop position
Solution Approach 2:
The control unit dynamically adjusts the motor deceleration rate based on the monitored relative position. This dynamic control allows the motor to decelerate at an optimal rate that balances quick response time with accurate positioning, ensuring the read position reaches the stop position within the last read pixel without excessive delay
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 solution allows for continuous and accurate image reading without misalignment, even during read-suspension events, by controlling the motor's stop position and resuming scanning from the next pixel, thereby maintaining image quality.
Implementation Method 1
an encoder configured to detect information about the relative movement
Data Source
AI summary
A reading apparatus includes an image sensor, a movement mechanism including a motor that relatively moves between a document and the image sensor, an encoder that detects information about the relative movement, and a control unit that controls driving of the motor and reading by the image sensor based on the detection by the encoder, wherein when a read-suspension event occurs during the reading, the control unit performs control such that the reading is continued while decelerating the motor, a relative position of a last read pixel with respect to a read position by the image sensor is monitored based on the detection by the encoder, and the driving of the motor is stopped when the read position is determined to reach a stop position set within the last read pixel, and the motor is driven again to resume the reading with a pixel next to the last read pixel.