An automatically adjusting magnetic resistance unit for an exercise device such as a bicycle trainer, in which the degree of resistance is automatically and non-linearly adjusted in relation to the rotational speed of a rotating member caused by the input of a user. The rotating member may be in the form of a flywheel having a number of supports extending between a hub and a rim. The supports define longitudinal grooves which slidably retain magnets that are biased inwardly toward the hub by biasing members. An electrically conductive member is located adjacent the flywheel. As the flywheel rotates in response to rotation of the bicycle wheel, the magnets interact with the conductive member to establish eddy currents that provide resistance to the rotation of the flywheel. The speed of rotation of the flywheel increases as the speed of rotation of the bicycle wheel increases, and centrifugal forces act on the magnets to cause the magnets to slide outwardly along the grooves in opposition to the bias of the biasing members. The outward movement of the magnets causes outward movement of the eddy current forces, to increase the resistance provided to rotation of the flywheel and the bicycle wheel. The variable resistance due to the increased or decreased rotational speed of the flywheel is smooth, based on the constant interaction of the counteracting forces of the biasing members and the centrifugal forces acting on the magnets.
A damping device includes a support base, a housing, a pivot shaft, a resistance wheel, a magnetic disk, a fixing disk, an action block, two urging balls, and a motor. Thus, the fixing disk is pushed to move relative to the magnetic disk by rotation of the action block to change the distance between the magnetic members of the fixing disk and the magnetic disk, so as to adjust the damping force applied by the resistance wheel on the rear wheel of the exercising cycle, so that the resistance values of the damping device can be adjusted arbitrarily so as to fit the requirements of different users.
A resistance generating device includes a friction wheel adapted to frictionally engage a bicycle wheel of a training bicycle to be rotated therewith, a first magnetically attractive member, and a second magnetically attractive member which is rotated with the friction wheel, and which is disposed to be spaced apart from the first magnetically attractive member. The first and second magnetically attractive members are configured to be shiftable towards or away from each other in response to the higher or lower speed of the second magnetically attractive member so as to increase or decrease a magnetically induced resistance force generated therebetween to be imparted to the bicycle wheel. The actuating mechanism is disposed to effect the relative shifting movement in response to the higher speed to force the first and second magnetically attractive members towards each other, thereby increasing the resistance force.
A rotational facility includes a barrel coupled to a driving device for being rotated and driven by the driving device, a wheel rotatably attached onto the barrel, and a braking device secured to the wheel for engaging with the barrel and for braking the wheel relative to the barrel. The braking device includes a housing secured to the wheel and one or more actuating members received in the housing for engaging with the barrel to brake the housing and the wheel relative to the barrel. The housing includes a brake member for engaging with and for actuating the actuating member to engage with the barrel. The housing includes a peripheral channel formed by inner and outer peripheral walls to receive the brake member.
An exercise system includes a user input arrangement; a rotatable member that rotates in response to an input force applied by a user on the user input arrangement; a power sensing arrangement that senses power applied to the rotatable member due to the input force applied by the user; and a variable resistance arrangement interconnected with the power sensing arrangement and with the user input arrangement. The resistance arrangement applies resistance to rotation of the rotatable member, and is variable in response to the power sensing arrangement to vary the resistance applied to the rotatable member. The variable resistance arrangement may be a brake that interacts with the rotatable member to resist rotation of the rotatable member, and to thereby resist the input force applied by the user. The variable resistance arrangement includes a controller for controlling the brake in response to the power sensing arrangement.
A bicycle training apparatus having an elevator assembly, a wheel support assembly operatively coupled to the elevator assembly, and a resistance interface assembly operationally coupled to the elevator assembly. The elevator assembly operates to raise and lower the wheel support assembly, and the resistance interface assembly provides an output signal proportional to the height of the wheel support assembly.
