Method for adjusting blade resistance

A method for adjusting a blade resistance, comprising the steps of:

• providing a blade seat connected to a rotating shaft extending in an axial direction, wherein the blade seat is rotated along with the rotating shaft;
• providing a sliding seat slidably fitted onto the rotating shaft in the axial direction;
• providing a plurality of blades surrounding the rotating shaft, wherein the blades each include a pivot end pivotally connected to the blade seat and a pivot portion pivotally connected to the sliding seat through a connecting member;
• providing an external force to drive the rotating shaft so that the blades are rotated synchronously around the rotating shaft in a fluid to obtain a rotational resistance;
• providing an adjustment force to drive the sliding seat to move in the axial direction, wherein each blade is rotated with the pivot end as a fulcrum to change an opening and closing angle between a reference line of the blade and an axis of the rotating shaft, so that a radius of rotation of the blade changes along with the opening and closing angle, thereby changing the magnitude of the rotational resistance;
• wherein the radius of rotation is a distance from an outermost edge of a free end opposite to the pivot end of the blade on the reference line to the axis and perpendicular to the axial direction, and each blade extends along the reference line between the pivot end and the free end.