Piezoelectric Micro-blower Diaphragm Bending Flow Rate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezoelectric micro-blowers face challenges in efficiently conveying compressive fluids like air without check valves, resulting in low flow rates due to limited displacement of the piezoelectric element and inefficient fluid discharge.
Innovation Solution
A piezoelectric micro-blower design featuring a diaphragm with a blower chamber, a first opening, and a second opening, along with an inflow path between two walls, allowing fluid to be drawn into and discharged from the chamber through varying distances caused by the diaphragm's bending, achieving high flow rates without check valves.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If check valves are used for conveying compressive fluid, then fluid discharge can be achieved, but the piezoelectric element must operate at low frequency which limits displacement and reduces flow rate
Solution Approach 1:
The invention removes check valves from the system entirely. Instead of using check valves to control fluid direction, the patent uses a diaphragm that bends to actively draw fluid in through the outlet, eliminating the need for check valves and enabling high-frequency operation for increased flow rate
Solution Approach 2:
The invention reverses the conventional approach by using the outlet to draw fluid in during the expansion phase, rather than using check valves to push fluid out during compression. This inverted mechanism allows the piezoelectric element to operate at high frequencies while maintaining effective fluid conveyance
2Productivity
If the piezoelectric element is driven at high frequency near resonance, then maximum displacement is obtained, but check valves cannot follow the displacement and fail to function
Solution Approach 1:
The invention removes check valves from the system entirely. Instead of using check valves to control fluid direction, the patent uses a diaphragm that bends to actively draw fluid in through the outlet, eliminating the need for check valves and enabling high-frequency operation for increased flow rate
Solution Approach 2:
The invention uses a dynamic diaphragm structure that can respond to high-frequency vibrations. The diaphragm's flexibility allows it to follow the piezoelectric element's rapid displacement at resonance frequencies, enabling the system to operate at maximum displacement without mechanical constraints
3Device complexity
If tapered ports are used to enable fluid flow without check valves, then check valves can be omitted, but fluid flows through both ports during each cycle reducing net discharge flow rate
Solution Approach 1:
The invention reverses the conventional approach by using the outlet to draw fluid in during the expansion phase, rather than using check valves to push fluid out during compression. This inverted mechanism ensures that fluid is drawn in through the outlet during expansion and discharged through the same outlet during compression, preventing backflow and maximizing net discharge flow rate
Solution Approach 2:
The diaphragm acts as an intermediary that actively controls fluid movement. By bending during expansion, it creates a suction effect that draws fluid in through the outlet, while during compression it forces fluid out through the same outlet, ensuring unidirectional net flow without requiring check valves
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 design enhances flow rates by ensuring fluid is drawn into and discharged from the blower chamber effectively, overcoming the limitations of previous technologies, and can be used as a cooling fan or air supply for electronic devices.
Implementation Method 1
a piezoelectric element, and a blower chamber formed between the blower body and the diaphragm. The piezoelectric micro-blower conveys compressive fluid by applying a voltage to the piezoelectric element to cause the diaphragm to bend
Data Source
Figure 1(a)~1(e)
Figure 2
Figure 3
AI summary
An object is to provide a piezoelectric micro-blower capable of efficiently conveying compressive fluid without use of a check valve and ensuring a sufficient flow rate. A blower body 1 has a first wall 1a and a second wall 1b. Openings 5a and 5b are formed in parts of the respective walls, the parts facing a center of a diaphragm 50. An inflow path 7 allowing the openings 5a and 5b to communicate with the outside is formed between the walls. By applying a voltage to a piezoelectric element 3 to cause the diaphragm 50 to vibrate, a part of the first wall 1a vibrates, the part being close to the first opening 5a. Thus, gas can be drawn from the inflow path 7 and discharged from the opening 5b.