Elliptical Trainer Linkage Mechanism for Wide Stride Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional elliptical trainers lack the ability to adjust the stride of the pedals to accommodate users of varying heights, leading to a narrow adjustment range and potential operational issues such as noise and reduced durability due to the use of wheels in slide mechanisms.
Innovation Solution
The elliptical trainer features a supporting frame with a resistance device, cranks, and operating units that include a combination of swing rods, amplitude-linking mechanisms, and pedal-supporting rods, allowing for a wide range of stride adjustment by varying the vertical position of the amplitude-linking mechanism, resulting in a smooth elliptical trajectory for the pedals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If wheels are employed in a slide mechanism to adjust stride, then stride adjustment is achieved, but noise is generated during operation and wheels wear after long-term use
Solution Approach 1:
The patent removes the wheel-based slide mechanism from the system and replaces it with a linkage mechanism consisting of connecting rods and pivots. This extraction of the harmful wheel component eliminates noise generation and wear issues while preserving the stride adjustment functionality through the alternative linkage design.
Solution Approach 2:
The patent substitutes the wheel-based sliding mechanical system with a pure linkage mechanical system using connecting rods and pivots. This replacement maintains the adjustability function while eliminating the harmful characteristics of wheels, achieving both noise reduction and durability improvement.
2Stability of the object's composition
If cranks move along a closed circular trajectory, then the elevation of the pivot must be higher than the shaft, but the pedal trajectory becomes quarter-moon shaped rather than elliptical
Solution Approach 1:
The patent divides the pedal mechanism into multiple segments: cranks, connecting rods, and pivots arranged in a specific configuration. This segmentation allows the system to achieve an elliptical pedal trajectory by combining the motions of individual segments, overcoming the limitation of single-crank circular motion while maintaining structural stability.
3Ease of operation
If the middle portion of the handle is tilted backward, then the operation becomes smooth, but the stride adjustment range remains narrow
Solution Approach 1:
The patent introduces a dynamic linkage mechanism with adjustable connecting rods that can change the stride length while maintaining operational smoothness. The linkage design allows the handle to remain tilted backward for smooth operation while the adjustable connectivity provides a wide stride adjustment range, resolving the contradiction between ease of operation and adaptability.
Data Source
AI summary
An embodiment of the present invention provides an elliptical trainer including structures featuring a first amplitude, a second amplitude, and a third amplitude. By the driving of cranks and the combination of the three amplitudes, the elliptical trainer's pedals move along a closed ellipse path. In addition, the first amplitude is more than twice or three times of the third amplitude, resulting in a wide adjustment range of the stride of the pedal. Accordingly, the elliptical trainer is applicable to users of various heights.