Segmented-Tooth Air Duct Damper for Precise Low-Flow Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional air dampers lack precise control over airflow at lower flow rates and higher static pressures, resulting in significant and uncontrollable changes in airflow when transitioning from a closed to a slightly open position.
Innovation Solution
An air damper assembly with a damper plate featuring multiple teeth of varying lengths and materials, including resilient and flexible portions, and an axle assembly that allows for precise rotation between fully open and closed positions, driven by a control system incorporating a pressure sensor and motor to achieve targeted airflow setpoints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a conventional damper blade is rotated from a closed position to a slightly open position, then airflow is permitted to pass through, but a large volume of air immediately passes through in an uncontrollable manner
Solution Approach 1:
The damper blade is segmented into multiple teeth of varying lengths around its periphery. These teeth create multiple narrow flow passages instead of a single large opening, allowing the blade to restrict airflow even when slightly rotated from the closed position. The segmentation enables progressive control of airflow volume as the blade rotates.
Solution Approach 2:
The teeth are distributed non-uniformly around the periphery of the damper blade, with varying lengths created by removing material from specific locations. This local variation in tooth length creates different flow resistance characteristics at different angular positions, enabling precise local control of airflow patterns and volume.
2Stress or pressure
If the static pressure in the ductwork is high, then airflow through the duct is maintained, but tiny movements of the blade damper result in significant changes in airflow
Solution Approach 1:
The segmented teeth create multiple narrow flow passages that collectively maintain stable airflow under high static pressure. The distributed nature of these passages prevents sudden airflow changes from minor blade movements, as the pressure is distributed across multiple restricted pathways rather than one large opening.
Solution Approach 2:
The damper blade is designed to rotate dynamically between fully open and fully closed positions with precise angular control. The varying tooth lengths create different flow characteristics at different rotation angles, enabling the system to adapt to varying pressure conditions and maintain stable airflow control throughout the range of motion.
3Quantity of substance
If the damper blade is made fully closed to block all airflow, then no air passes through, but precise control at lower flow rates cannot be achieved
Solution Approach 1:
The segmented teeth create multiple adjustable flow passages that can be progressively opened or closed by rotating the blade. This segmentation allows for fine-grained control of airflow volume, enabling precise regulation at low flow rates while maintaining the capability to achieve complete closure when all teeth are positioned against the duct wall.
Solution Approach 2:
The varying lengths of the teeth create different flow resistance parameters at different angular positions. By rotating the blade to different angles, the effective flow area and resistance parameters change in a controlled manner, enabling precise adjustment of airflow volume across the entire range from fully closed to fully open positions.
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 provides enhanced control and resolution of air pressure, allowing for more precise management of airflow at nearly closed or open positions, even at higher pressures, without the need for accelerating air past vortex shedders, thereby enabling higher flow rates and improved control.
Implementation Method 1
each of the teeth includes a resilient portion proximate the periphery and a flexible portion. The resilient portion has a greater stiffness than the flexible portion.
Data Source
AI summary
An air damper assembly for an air duct having an interior wall and an exterior wall is provided. The air damper assembly includes a damper plate having a periphery and multiple teeth spaced at least partially around and extending from the periphery. The multiple teeth vary in length from a maximum to a minimum over a span of approximately 90 degrees around the periphery. The air damper assembly further includes an axle assembly fixedly coupled to the damper plate and rotatably coupled to the air duct. Rotation of the axle assembly causes the damper plate to rotate within the air duct between a fully open position and a fully closed position to increase or decrease a flow of fluid through the air duct.