Liquid Ejection Head Bubble Removal Through Permeable Membranes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Bubbles entering liquid ejection heads during replacement or operation can cause insufficient pressure for liquid ejection and potential leakage, affecting performance and stability.
Innovation Solution
A liquid ejection head design with a filter chamber and gas collection hollow portion utilizing pressure differentials to collect and discharge bubbles, combined with a unidirectional pump system for effective bubble management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a filter chamber with a non-permeable filter is used to trap bubbles, then bubble trapping capability is improved, but bubble collection from the gas collection hollow portion becomes insufficient
Solution Approach 1:
The filter chamber is designed with different permeability characteristics in different regions: the filter portion has low permeability to trap bubbles, while the gas collection hollow portion has high permeability to allow bubble passage. This local differentiation of permeability enables both bubble trapping and effective bubble collection simultaneously
Solution Approach 2:
The gas collection hollow portion acts as an intermediary structure between the filter chamber and the external environment. It receives bubbles from the filter chamber through its permeable defining wall and facilitates their discharge to the outside, solving the problem of bubble accumulation
2Object-affected harmful factors
If the filter chamber is located vertically above the pressure chambers, then bubble formation in pressure chambers is reduced, but bubbles formed between the filter chamber and pressure chambers cannot be collected
Solution Approach 1:
The gas collection hollow portion extends in the vertical dimension below the filter chamber, creating a three-dimensional bubble collection pathway. This allows bubbles formed in the space between the filter chamber and pressure chambers to be captured through the permeable defining wall of the gas collection hollow portion, which extends downward to intercept these bubbles
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
Enhances the reliability of liquid ejection by effectively suppressing bubble effects, ensuring stable operation and preventing leakage.
Implementation Method 1
a gas collection hollow portion adjoining the filter chamber with a permeable defining wall therebetween. In this liquid ejection head, the pressure inside the gas collection hollow portion is set to be lower than the pressure inside the filter chamber to cause air in the filter chamber to permeate through the permeable defining wall by means of the pressure difference
Implementation Method 2
the pressure inside the gas collection hollow portion is set to be lower than the pressure inside the filter chamber to cause air in the filter chamber to permeate through the permeable defining wall by means of the pressure difference
Data Source
Figure 1A~1B
Figure 2
Figure 3
AI summary
A liquid ejection head includes: an ejection port(13) for ejecting the liquid; a pressure chamber(12) provided with an energy generation element(15) which generates an energy for ejecting the liquid from the ejection port; a first liquid reservoir part(120,130,520A) communicating with one end of the pressure chamber and capable of holding the liquid to be supplied to the pressure chamber; a first depressurization chamber(760A) adjoining the first liquid reservoir part with a first gas permeable membrane(710A) therebetween and configured such that an inside of the first depressurization chamber is depressurizable; a second liquid reservoir part(140,150,520B) communicating with another end of the pressure chamber and capable of holding the liquid collected from the pressure chamber; and a second depressurization chamber(760B) adjoining the second liquid reservoir part with a second gas permeable membrane(710B) therebetween and configured such that an inside of the second depressurization chamber is depressurizable.