Ink Supply Timing Control for Liquid Ejection Apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image forming apparatuses using liquid-ejection recording methods face inefficiencies in ink supply management, leading to reduced printing speed due to inaccurate detection of ink levels, resulting in either insufficient or excessive negative pressure, and increased apparatus size and weight from additional detection and control components.
Innovation Solution
The implementation of a system with a recording head, sub tank, main tank, liquid feed unit, displacement member, and multiple detectors and calculation units that determine the optimal ink supply timing and amount based on detected ink levels and consumption patterns, allowing for continuous printing without interrupting the process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the carriage is moved to a predetermined detection position to detect the displacement member for determining ink supply timing, then the ink supply timing can be determined, but the printing operation must be stopped, reducing printing speed
Solution Approach 1:
The patent applies preliminary action by pre-calculating the detection position of the displacement member based on the carriage position and stored displacement amounts. The controller stores the displacement amount detected at the ink full position and calculates the detection position in advance, allowing ink supply timing determination without stopping the carriage, thus maintaining printing speed while ensuring detection accuracy
Solution Approach 2:
The patent replaces the mechanical system of physically moving the carriage to a detection position with an information processing system. The controller calculates the detection position based on the carriage position and stored displacement data, substituting physical movement with computational determination, thereby eliminating the need to stop printing for detection
2Measurement precision
If detectors and control components are added to accurately detect ink levels and control supply timing, then ink supply accuracy is improved, but the apparatus size and weight increase
Solution Approach 1:
The patent applies multi-functionality by making the existing displacement member serve dual purposes: it detects both the ink full position and provides displacement amount information for determining ink supply timing. The same displacement member and detector are used for multiple detection functions, eliminating the need for additional detectors and reducing apparatus weight while maintaining detection accuracy
Solution Approach 2:
The system uses the existing displacement member and detector infrastructure to provide self-service for ink supply timing determination. The displacement member automatically provides position information that the controller uses to calculate detection positions and determine ink supply timing, eliminating the need for separate detection systems
3Device complexity
If ink supply is performed based on inaccurate detection, then the apparatus structure can be simpler, but insufficient or excessive ink supply occurs, affecting printing quality
Solution Approach 1:
The patent implements feedback by using the detected displacement amount to calculate the detection position and determine ink supply timing. The system continuously monitors the carriage position and displacement member position, using this feedback information to accurately determine when ink supply should occur, ensuring reliable ink supply without excessive system complexity
Solution Approach 2:
The system performs preliminary calculation of the detection position based on stored displacement amounts and current carriage position. This preliminary determination allows the system to prepare for ink supply timing without waiting for actual detection events, improving reliability while keeping the detection system simple
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 ensures accurate and efficient ink supply management, maintaining optimal negative pressure and preventing interruptions during printing, thereby enhancing printing speed and efficiency while minimizing the apparatus's size and weight.
Implementation Method 1
The negative-pressure forming unit includes a flexible member (film member) to form one face of an ink storage part to store ink and an elastic member to urge the flexible member outward
Implementation Method 2
The sub tank has a displacement member (also referred to as detection member or detection feeler) to displace with the displacement of the flexible member
Data Source
AI summary
An image forming apparatus includes a body, a recording head, a sub tank, a carriage, a main tank, a liquid feed unit, a displacement member, first and second detectors, first to third calculation units, a determination unit, and a supply control unit. When the first detector detects the displacement member, the determination unit determines a main scanning position of the carriage at which consumption amount of the liquid is equal to an amount corresponding to a difference calculated by the second unit, based on a relation calculated by the third unit. The control unit causes the feed unit to start supply of the liquid from the main tank to the sub tank when the carriage arrives at the main scanning position, and stop the supply when the liquid is supplied at an amount corresponding to a difference detected by the first unit after the first detector detects the displacement member.