Liquid Ejection Device Flexible Bag Pressure Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid ejection devices face challenges in maintaining negative pressure within the liquid ejection head due to variations in temperature and pressure, leading to potential liquid leakage, as the sealed gas volume changes and gas permeation into the ink tank creates pressure fluctuations and rocking issues.
Innovation Solution
A liquid ejection device design that uses a flexible containing bag with a non-compressible liquid filler in a separate containing space, minimizing density differences and gas exposure, and employing a pressure adjusting unit to maintain stable pressure, reducing the likelihood of liquid leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If gas is sealed in the second containing space to maintain negative pressure, then the internal pressure of the head is maintained to be a negative pressure, but the volume of the gas varies along with temperature or atmospheric pressure changes causing liquid pressure fluctuations
Solution Approach 1:
The patent changes the physical state of the filling material from gas to liquid. By using liquid filler instead of sealed gas, the system eliminates volume fluctuations caused by temperature and atmospheric pressure changes, while still maintaining the ability to control internal pressure for negative pressure operation in the head.
Solution Approach 2:
The patent transitions from pneumatic (gas-based) pressure control to hydraulic (liquid-based) pressure control. The liquid filler provides stable pressure transmission without the compressibility issues of gas, enabling more reliable maintenance of negative pressure in the head while resisting external pressure variations.
2Ease of operation
If the ink tank is made flexible to change volume with liquid ejection, then the liquid ejection function is enabled, but the tank rocks greatly when impact is applied causing pressure variations
Solution Approach 1:
The patent creates a homogeneous density distribution by filling the entire housing with liquid filler, eliminating the gas-liquid density difference that causes rocking. The uniform liquid medium absorbs impact forces evenly, preventing the flexible ink tank from rocking greatly during impact while maintaining its volume-change capability for liquid ejection.
3Ease of manufacture
If the flexible member is made of material that allows some gas permeation, then manufacturing is easier, but gas enters the ink tank creating air bubbles and increasing liquid pressure
Solution Approach 1:
The patent extracts the harmful gas phase from the system entirely by replacing it with liquid filler. This eliminates the problem of gas permeation and air bubble formation while maintaining the flexibility and manufacturability advantages of using flexible materials for the ink tank.
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
The solution effectively suppresses pressure variations and rocking of the containing bag, maintaining negative pressure within the head and reducing liquid leakage, even under temperature and pressure changes, while allowing for efficient liquid ejection.
Implementation Method 1
it is required to maintain the internal pressure of the head to be a negative pressure
Implementation Method 2
a pressure adjusting unit for adjusting the pressure of the liquid filler in the second containing space
Implementation Method 3
The ink tank is a bag-shaped container having flexibility, and the volume of the containing bag changes along with the ejection of the liquid
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
There is provided a liquid ejection device including a head for ejecting a liquid, a liquid containing unit, a liquid filler, and a pressure adjusting unit, in which the liquid containing unit includes a sealed housing and a flexible member provided in the housing, the housing includes a first containing space communicating with the head and a second containing space partitioned from the first containing space through use of the flexible member, the first containing space contains the liquid, and the liquid filler is filled into the second containing space, the pressure adjusting unit communicates with the second containing space, and adjusts the pressure of the liquid filler filled into the second containing space so as to maintain a negative pressure with respect to the head.