Abstract: A method for controlling a normal force exerted in a frictional contact of a friction type continuously variable transmission with a rotatable input shaft and a rotatable output shaft, includes the steps of: generating a first parameter signal that is representative of changes in one of, or a ratio or difference between both of, a rotational speed of the input shaft and a rotational speed of the output shaft, generating a second parameter signal that is representative of changes in the normal force in the frictional contact of the transmission, generating a third parameter signal that is representative of and is preferably proportional to the multiplication of the first and second parameter signals, and: controlling the normal force in the frictional contact in dependence on a characteristic of the third parameter signal.

Abstract: By providing a plurality of cylindrically shaped tube members nested together in coaxially aligned relationship, with each tube member being connected to a separate and independent control segment, with the control segments being constructed for raising and lowering the associated tube segment, an easily produced, reliable, dependable, and highly portable telescopically extendable and retractable multi-element system is realized. In the preferred embodiment, each control segment incorporates a separate endless loop drive belt which is cooperatively associated with a pair of pulleys mounted at opposed ends of the segment. Furthermore, each control segment is interconnected to the endless loop drive belt of an adjacent segment for causing all of the segments to move simultaneously in response to the initial movement of a first control segment.

Abstract: A pulley comprising a first pulley wheel and a second pulley wheel and a ratchet acting between the two pulley wheels. When substantially equal force is applied to each pulley wheel in use on a rope tail side causing the pulley wheels to rotate, a low gear ratio is achieved through a rope, chain or the like acting on a load through a block. When one pulley wheel is prevented from rotating and a force is applied to the other pulley wheel in use on a rope tail side causing it to rotate, then a higher gear ratio is achieved through a rope or chain or the like acting on a load through a block. When force is applied to the first wheel on a rope tail side and the second pulley wheel is allowed to rotate, then a still higher ratio is achieved in use through a rope, chain or the like acting on a load through a block.

Abstract: A drive, preferably a gate drive with a belt transmission encompassing a drive pulley and an output pulley. According to the invention the drive pulley consists of at least one cylinder with inwardly tapering flanges at its ends. A round belt, rope or similar serves as a drive agent, which is wound a number of times around the cylinder. The return strand of the round belt, rope or similar can be held continuously under tension.