1. Field of the Invention
The present invention relates to an elliptical trainer, especially to an elliptical trainer that has two crank assemblies and allows a user to perform smooth movements.
2. Description of the Prior Art(s)
An elliptical trainer is a stationary exercise machine that simulates walking or running without causing excessive pressure to the knee joints and decreases the risk of impact injuries. The elliptical trainer offers a non-impact cardiovascular workout, capable of varying from low to high intensity based on a resistance preference set by users.
A conventional elliptical trainer has a base, a flywheel, a handle assembly, two linkage assemblies and a resistance assembly. The flywheel and the handle assembly are separately mounted'rotatably on the base. The linkage assemblies are respectively mounted on two'opposite sides of the base and connect pivotally to the handle assembly and eccentrically to the flywheel. Each linkage assembly has multiple links pivotally connecting to each other in series. The resistance assembly applies resistance to the flywheel. When the conventional elliptical trainer is operated, the linkage assemblies rotate the flywheel. However, as the links of the linkage assemblies swing or rotate, one or more toggle positions exist so that the linkage assemblies and the flywheel do not operate smoothly. Consequently, the conventional elliptical trainer is not able to smoothly simulate the walking or running movements.
To overcome the shortcomings, the present invention provides an elliptical trainer having two crank assemblies to mitigate or obviate the aforementioned problems.