Abstract: The invention is an exercise device which creates a controlled and infinitely variable resistance profile using a pair of rods that are wrapped about a common axis with a varying pitch. A slide unit is attached to the rods with rollers. When the slide unit is moved in a linear motion, the movement of the rollers on the rods causes the rods, and a shaft on which they are mounted to rotate. In one embodiment, the rotation of the shaft is used to move one or more units of a set of stacked weights. In a second embodiment, a rotation motion of the shaft on which the rods are mounted, causes a linear motion to the slide unit which is attached to a set of stacked weighs.

Abstract: The invention is a portable exercise device which creates a controlled and infinitely variable resistance profile. The exercise device, creates this infinitely variable resistance using springs or elastic bands to create the input resistance versus the use of a weight stack as normally used in most exercise equipment. The advantage of this device over conventional exercise devices is that usage of this resistance medium creates a portable exercise device that can create an infinitely variable resistance profile. The exercise devise may be used while traveling and/or in the home. The ease with which the input resistance elements, such as elastic bands or springs, may be changed makes this device much more versatile for exercising a wider range of muscle groups while using one portable machine.

Abstract: The invention is to a weight device that creates a controlled and infinitely variable transpositional force greater than the weight being lifted. A vertical shaft has a pair of grooves which spiral about the shaft, increasing the slope from the bottom to the top of the shaft. A pair of rollers in the grooves have shafts that extend through and support a sleeve that is placed over the vertical shaft. The roller shafts are mounted in a pair of mounts that are on each side of the vertical shaft. A sprocket pulley is mounted on an end of the vertical shaft. As the sprocket is turned, the rollers are moved up the grooves, moving the sleeve upward against an increasing resistance to upward movement. A stack of weights surrounds the sleeve for movement therewith.