Magnetic Resistance Adjustment for Uniform Exercise Load Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional resistance adjustment devices in exercise apparatuses exhibit non-uniform and unpredictable resistance change, particularly during high-intensity interval training, due to the non-linear increase and decrease of resistance levels, leading to user discomfort and inefficiency.
Innovation Solution
A resistance adjustment device with non-circular cross-section magnets that ensure a uniform and predictable resistance change by gradually increasing the overlapping area with the metal disc, maintaining consistent resistance response throughout the adjustment range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a circular cross-section magnet is used in the resistance adjustment device, then the structure is simple and easy to manufacture, but the resistance change becomes non-uniform and unpredictable during adjustment
Solution Approach 1:
The patent applies asymmetry by changing the magnet cross-section from a circular symmetric shape to a non-circular asymmetric shape. Specifically, the magnet has a rectangular cross-section with width W and height H where W≠H, creating asymmetric dimensions that produce uniform resistance change during rotation. This asymmetric geometry ensures that the overlapping area between the magnet and metal disc increases linearly with rotation angle, resolving the non-uniform resistance issue while maintaining manufacturing simplicity.
Solution Approach 2:
The patent changes the geometric parameters of the magnet cross-section from equal dimensions (circular) to specific unequal dimensions (rectangular with width W and height H). By carefully selecting these parameters according to the formula involving the metal disc radius R and the desired resistance adjustment characteristics, the system achieves uniform resistance change. This parameter optimization allows the magnet to interact with the metal disc in a controlled manner that produces linear resistance increase during rotation.
2Force
If the magnet is positioned farther from the rotation axis, then the overlapping area with the metal disc is smaller and resistance is lower, but the adjustable resistance range is limited
Solution Approach 1:
The patent applies dynamics by making the magnet position variable through rotation rather than fixed. The bracket holding the magnet can rotate about the swing axis, dynamically changing the magnet's angular position relative to the metal disc. This dynamic positioning allows the overlapping area to vary continuously from minimum to maximum, providing a wide adjustable resistance range. The system transitions from static to dynamic control, enabling smooth resistance adjustment across multiple levels.
Solution Approach 2:
The patent introduces angular rotation as an additional dimension for resistance control. Instead of only moving the magnet radially inward or outward from the rotation axis (one-dimensional adjustment), the system adds rotational movement about the swing axis. This second dimension allows independent control of the overlapping area, enabling the magnet to sweep across different portions of the metal disc and achieve a broader resistance adjustment range while maintaining optimal positioning.
3Force
If the magnet moves closer to the rotation axis during adjustment, then the overlapping area increases and resistance increases, but the resistance change rate is non-uniform
Solution Approach 1:
The asymmetric rectangular cross-section of the magnet is key to achieving uniform resistance change. As the bracket rotates, the asymmetric geometry ensures that the overlapping area between the magnet and metal disc increases at a constant rate with rotation angle. This is because the rectangular shape with specific width and height dimensions creates a linear relationship between rotation angle and overlapping area, unlike circular magnets that produce non-linear changes. The asymmetry transforms the non-uniform resistance change into a uniform one.
Solution Approach 2:
The patent optimizes the geometric parameters of the magnet (width W, height H) based on the metal disc radius R and desired resistance characteristics. By carefully selecting these parameters, the system achieves a linear relationship between bracket rotation angle and overlapping area. This parameter optimization ensures that resistance changes uniformly during adjustment, improving the linearity and predictability of resistance change without requiring complex control mechanisms.
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 device provides a uniform and predictable resistance adjustment, enhancing user experience by ensuring consistent resistance change, particularly suitable for high-intensity interval training.
Implementation Method 1
the magnet 98 causes eddy currents induced in the metal disc 93
Implementation Method 2
the magnet 98 causes eddy currents induced in the metal disc 93
Implementation Method 3
The magnet has a non-circular cross section defining a first edge and a second edge, and both the first edge and the second edge have a front end and a rear end
Data Source
AI summary
A resistance adjustment device of an exercise apparatus include a metal disc that can be driven by movement of a user, a bracket that can be controlled by the user and at least one magnet disposed on the bracket. The magnet can be movable along an adjustment path to approach or move away from a rotation axis of the metal disc so as to increase or decrease a projection area of the magnet on the metal disc for adjusting rotational resistance of the metal disc. The magnet has an irregular quadrilateral cross section gradually widening from a front side closer to the rotation axis to a rear side farther away from the rotation axis, so that during the period of the magnet moving along the adjustment path to approach the rotation axis at a constant speed, the increase rate of the projection area will be gradually accelerated.