Abstract: A stationary exercise cycle is disclosed having a drive wheel which receives both user driving force and automatically controlled friction brake resistance, i.e., it is a single-stage device. Free-wheeling is provided between a user-driven shaft and the periphery of the drive wheel, which is braked by a friction belt. Automatic resistance control is provided by an electronic system, which receives actual load information from a load cell, and RPM information from a speed sensor. The friction belt is tightened or loosened by a motor-driven pulley, in response to signals indicating an "error" between load command and actual load. The load information is accurately obtained by a pivoted member to which both ends of the friction belt are attached.

Abstract: An exercising apparatus is disclosed which simulates stair-climbing. In order to reduce breakage problems in the force-transmitting structure between each pedal and a one-way rotating drive shaft, a pair of pulley wheels, each associated with a pair of cables, are used. Each pulley wheel rotates the drive shaft, and is pulled in one direction of rotation by a pedal-connected cable, and in the other direction of rotation by a cable connected to a return spring. Each cable on each pulley wheel reels into and out of helical grooves formed in the periphery of the pulley wheel.

Abstract: An exercise apparatus is disclosed which simulates a stair climber, and which determines the amount of user exercise by the speed of rotation of a flywheel. The speed of the flywheel is controlled to maintain the desired speed of stair climbing by a friction belt engaging the flywheel. A rotary electrical motor is moved in one direction to tighten the belt on the flywheel and in the opposite direction to loosen the belt on the flywheel. A slack sensor determines whether the motor has been moved to a limit in the belt-loosening direction. Incremental changes of motor energy are used to gradually reduce an error signal between command speed and actual speed. Pulse width modulation is used to vary the motor energy in accordance with the size of the error signal.