Inkjet Print Head Buffer Chamber and One-Way Valve Backflow Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet printing apparatuses face issues with ink backflow and air volume changes in the circulation system, leading to potential ink leakage or atmospheric suction due to temperature changes, especially when the ink tank is positioned higher than the print head, and existing solutions require careful positional alignment of buffer chambers and one-way valves to prevent these issues effectively.
Innovation Solution
The apparatus includes a buffer chamber within the print head or collection flow path, which is volume variable, and a one-way valve between the buffer chamber and the tank in the collection flow path, ensuring effective ink circulation and preventing backflow by maintaining a suitable pressure and flow rate, even when the tank is positioned higher than the print head.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the tank is disposed higher than the print head in the vertical direction to utilize gravity for ink supply, then ink supply to the print head is improved, but ink backflow to the collection flow path occurs due to water head difference
Solution Approach 1:
A one-way valve is introduced as an intermediary component between the tank and the collection flow path. This valve allows ink to flow downward from the tank to the print head utilizing gravity, but prevents ink from flowing back upward into the collection flow path, thus resolving the contradiction between improved ink supply and backflow prevention
2Reliability
If a buffer chamber is provided in the circulation path to absorb air volume changes due to temperature variations, then atmospheric suction and ink leakage are prevented, but the positional relation between the buffer chamber and one-way valve must be carefully considered to maintain both functions
Solution Approach 1:
The one-way valve acts as an intermediary that separates the functions of the tank (ink supply) and the buffer chamber (air volume absorption). By positioning the one-way valve between the tank and buffer chamber, it mediates the flow control while allowing the buffer chamber to freely expand and contract to absorb air volume changes without compromising the backflow prevention function
Solution Approach 2:
The circulation system is segmented into distinct functional zones: the tank zone for ink supply, the one-way valve zone for flow control, and the buffer chamber zone for volume compensation. This segmentation allows each component to perform its function independently without interfering with others, simplifying the overall positional arrangement
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 configuration effectively prevents ink backflow and absorbs air volume changes, maintaining stable ink circulation and preventing ink leakage or atmospheric suction, thus ensuring reliable printing operations.
Implementation Method 1
a one-way valve is provided between the buffer chamber and the tank in the collection flow path
Implementation Method 2
there may be a case where atmosphere is drawn from the ejection opening due to the contraction of air in the flow path according to temperature changes or a case where ink is leaked from the ejection opening due to the expansion of air
Data Source
AI summary
An inkjet printing apparatus includes a tank, a print head including a pressure chamber filled with ink supplied from the tank and an ejection opening which is communicated with the pressure chamber and which ejects ink filled in the pressure chamber a supply flow path for supplying ink from the tank to the print head, a collection flow path for collecting ink from the print head to the tank, a circulation unit configured to circulate ink so as to flow through the supply flow path, an inside of the pressure chamber, and the collection flow path, and a buffer chamber disposed inside the print head or in the collection flow path and which is volume variable. The tank is disposed higher than the print head in a vertical direction, and a one-way valve is provided between the buffer chamber and the tank in the collection flow path.