Printer Carriage Control for Obstructed Encoder Scale
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In inkjet printers, obstacles on the encoder scale can impede accurate measurement of the carriage's position and speed, leading to unstable movement control and image quality issues due to incorrect speed detection and stopping errors.
Innovation Solution
A control system that determines the presence of obstructed areas on the encoder scale and adjusts the movement speed of the carriage by selecting between two control methods: maintaining a constant speed in both processing and non-processing sections when an obstruction is present, or moving at a higher speed in non-processing sections when no obstruction is detected.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the carriage moves at high speed in non-processing sections, then productivity is improved, but measurement precision deteriorates when obstacles block the encoder scale
Solution Approach 1:
The system performs preliminary detection of obstacles on the encoder scale during a detection movement phase before actual processing. By identifying obstructed areas in advance and storing this information, the system can prepare appropriate control strategies beforehand, preventing measurement errors from affecting high-speed operation.
Solution Approach 2:
The control method dynamically adjusts the carriage movement strategy based on real-time detection of obstructed areas. When obstacles are detected, the system switches from high-speed constant velocity control to accelerated control, adapting the movement profile to accommodate measurement limitations while maintaining overall productivity.
2Productivity
If the carriage is accelerated or decelerated in high-speed range, then productivity is improved, but stability of movement control deteriorates when reading is impeded
Solution Approach 1:
The system detects obstacles during a preliminary detection movement and stores the obstructed area information before actual high-speed operation begins. This advance preparation allows the control unit to anticipate potential reading failures and adjust control strategies accordingly, maintaining stability during acceleration and deceleration phases.
Solution Approach 2:
The system continuously monitors encoder scale reading status during movement and compares it with pre-detected obstacle positions. When reading failures are detected in real-time, the control unit receives feedback and adjusts motor control parameters to maintain stable carriage movement, preventing control instability during high-speed operation.
3Measurement precision
If obstacles are present on the encoder scale, then measurement precision deteriorates, but device complexity increases due to need for multiple control methods
Solution Approach 1:
The system performs obstacle detection during a preliminary detection movement phase, storing the results in memory before actual processing begins. This approach identifies measurement issues in advance without requiring complex real-time processing during high-speed operation, simplifying the control architecture while maintaining measurement accuracy.
Solution Approach 2:
The movement path is segmented into different sections (acceleration section, constant velocity section, deceleration section) with distinct control strategies applied to each. The control unit selectively applies appropriate control methods based on the section being traversed and detected obstacle locations, managing complexity through modular, section-based control rather than a monolithic approach.
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 allows for stable high-speed movement of the carriage while minimizing the impact of measurement errors caused by obstacles, thereby improving image quality and printing efficiency.
Implementation Method 1
a sensor configured to move relative to the encoder scale in association with the moving body to output an encoder signal by reading the encoder scale
Data Source
AI summary
In a control system, a controller is configured to determine presence or absence of an obstructed area within the intermediate section, and control movement of the moving body in accordance with a selected one of controlling methods including a first and a second control methods. The first control method causes the moving body to move at a first constant speed in the processing section defined within the intermediate section and at a second constant speed faster than the first constant speed in at least a part of a non-processing section within the intermediate section and other than the processing section, the first control method being selected when the obstructed area is absent. The second control method causes the moving body to move at the first constant speed in the processing section and the non-processing section, the second control method being selected when the obstructed area is present.