Bistable valve
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ventilation management systems in buildings are complex and require sophisticated motorization to control air flow, which can be costly and difficult to maintain, and often only allow proportional adjustment based on humidity.
Innovation Solution
A bistable valve system using flexible shape memory alloy wires that contract and expand with temperature changes to move the valve between two positions, simplifying the motorization and allowing non-proportional operation based on user or system commands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If small electric motors are used to motorize the damper for continuous air flow management, then the control flexibility and ability to manage multiple parameters is improved, but the device complexity and maintenance difficulty increase
Solution Approach 1:
The patent replaces the electric motor (electromechanical system) with a shape memory alloy wire (smart material system). The SMA wire directly converts electrical energy to mechanical motion through resistive heating, eliminating the need for complex motor components, gears, and mechanical linkages. This substitution maintains control flexibility while dramatically reducing device complexity.
Solution Approach 2:
The patent changes the control parameter from continuous rotational position to binary heating state (heated/not heated). By controlling the electrical resistance and heating duration of the SMA wire, the system can precisely position the damper at desired angles without requiring complex feedback mechanisms, thus simplifying the overall control system while maintaining adaptability.
2Productivity
If small electric motors are used to motorize the damper, then the ability to respond to user or system commands is improved, but the maintenance operations become more difficult
Solution Approach 1:
The patent extracts the motor function from the traditional motorized damper system and replaces it with a simple shape memory alloy wire. The SMA wire can be easily removed and replaced if faulty, unlike integrated motors that require complex disassembly. This extraction principle maintains rapid response capability while dramatically improving ease of maintenance.
Solution Approach 2:
The SMA wire is a simple, inexpensive component that can be easily replaced if it fails, rather than repairing a complex motor assembly. The wire's simplicity makes it more reliable and easier to maintain, aligning with the principle of using simple, replaceable components instead of complex, repairable systems.
3Extent of automation
If proportional adjustment based on humidity is used, then the automatic control capability is improved, but the ability to manage multiple parameters and perform non-proportional operation is limited
Solution Approach 1:
The patent transforms the static, humidity-proportional control into a dynamic, multi-parameter control system. The SMA wire's position can be adjusted based on any control signal (humidity, temperature, user preference, energy management), allowing the damper to respond non-proportionally to different parameters. The system's dynamics are enhanced by the ability to hold position and respond to various input types.
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 system significantly reduces the complexity of motor means, simplifies maintenance, and allows for flexible control of air flow based on various parameters, not just humidity, while maintaining energy efficiency by only consuming power during position changes.
Implementation Method 1
said drive means comprise at least two flexible wires made of shape memory alloy. According to the invention, said wires contract when heated and expand when cooling
Implementation Method 2
said wires contract when heated and expand when cooling
Implementation Method 3
each wire being subjected to heating means connected to an electronic control unit capable of alternately activating the heating means of at least the first wire or the heating means of at least the second wire
Data Source
AI summary
The invention relates to a flapper device for regulating airflow in an air passage opening made in a wall, comprising a flapper disposed on one face of the wall at the opening's outlet, movable between two positions relative to the opening: a position of closing the opening and a position of allowing airflow. This device is characterized in that it comprises flapper drive means associated with means for guiding its movement, including a pivoting zone between two stable, stop-start positions corresponding to the two positions of closing the opening and allowing airflow. Said drive means comprise at least two flexible wires made of a shape-memory alloy, said wires contracting when heated and expanding upon cooling.At least one first wire is fixed between one side of the flap and the wall or an element attached to the wall and at least one second wire is fixed between the other side of the flap and the wall or an element attached to the wall.