1. Field of the Invention
The present invention relates generally to an exercise machine, and more particularly to a load controller of a magnetic brake for the exercise machine.
2. Description of the Related Art
Exercise machines, such as bike and air walker, usually have a brake to provide load for exercise. Typically, the brakes are classified into frictional type and magnetic type. The magnetic type brake provides magnets beside a flywheel that the flywheel is braked by the magnetic force of the magnets. The magnets are adjustable for a distance between the flywheel and the magnets to change the value of the magnetic force acted on the flywheel.
Chen's invention (U.S. Pat. No. 5,466,203) disclosed a magnetic brake, which provides a level with magnets thereon beside a flywheel. The level is moved to change the distance between the magnets and the flywheel. Wei et al., U.S. Pat. No. 5,848,953, taught a magnetic brake that magnets are mounted in a cavity of a flywheel. The magnets are drawn by a rope for movement along a diameter direction of the flywheel. Wei et al., U.S. Pat. No. 5,851,165, taught that the magnets are moved by a cam. The inventions, U.S. Pat. Nos. 5,879,273 and 6,234,938, taught that the magnets are moved toward or away from the flywheel.
The ranges of braking power output of above brakes are fixed after they are made. As we know, men usually have greater strength than women and children, and west people usually have greater strength than east people. The ranges of braking power output cannot meet all kinds of peoples' requirements.
The primary objective of the present invention is to provide a load controller for an exercise machine, which the range of the load power output is adjustable by the designer or user.
According to the objective of the present invention, a load controller, which is mounted on a flywheel of an exercise machine, comprising a base mounted on the flywheel. A rotator is pivoted on the base for rotation, on which connecting portions are provided. Arms have ends pivoted on the base around the rotator, on which at least a magnet and a connecting portion are provided, and connecting devices have opposite ends connected to the connecting portions of the arms and the rotator respectively, such that the arms are moved while the rotator is rotated.
As shown in
A base 16 is consisted of two disks 18 and 20, each of which has posts 22 thereon for connection, such that a space is left between the disks 18 and 20. The disk 18 has a round protrusion 24 at a center of an interior side thereof and three spring bases 26 around the protrusion 24, in each of which a spring 28 is installed. The protrusion 24 has a gap 30 on a circumference thereof.
A rotator 32 has a hole 34 at a center thereof and a block 26 on a sidewall of the hole 34. The hole 34 of the rotator 32 is fitted to the protrusion 24 of the base 14, and the block 26 is received in the gap 30, such that the rotator is rotated in a predetermined angle. It is easy to understand that the gap may be on the rotator, and the block may be on the protrusion (not shown). The rotator 32 has three connecting portions 38 on the circumference, which are recesses in the present invention.
Three arms 40, on each of which two permanent magnets 42 are mounted respectively, have ends pivoted on the interior side of the disk 18 around the rotator 32. The springs 28 urge the arms 40 outwards respectively, such that the arms 40 rest on the posts 22 respectively. Each of the arms 40 has a connecting portion 43, which is a recess in the present invention, adjacent to a free end thereof.
Three connecting devices 44, each of which has ball joints 441 on opposite ends, have the joints 441 engaged with the connecting portions 38 and 43 of the rotator 32 and the arms 40 respectively, such that the arms 40 are moved by the rotation of the rotator 32. In the present invention, the connecting devices 44 are rigid bars, however, the connecting devices may be flexible members, such as metallic wires, ropes or chains.
As shown in
The reduction of the braking power of the load controller 10 of the present invention is directly relative to a vertical distance d of the movement of the connecting portion 38 of the rotator 32 rather than an angle of rotation of the rotator 32. In other words, under a condition of the rotator rotating for a predetermined angle, the arms are moved for different distances while the positions of the connecting portions are difference