Abstract: A method is described for changing gear-ratio by displacing at least one part of the engaging surface of a composite gear (21) and aligning it to the engaging surface of another gear (22), thus permitting a complementary third gear (25) engaged to the engaging surface, to shift from one composite gear to a different composite gear, while being constantly engaged. The method can be employed in a device, which can be used to form a gear-based, continuously engaged, variable transmission. Such a transmission, enhanced by—being combined with a differential assembly and the appropriate gearing, can provide rotational motion at various speeds in one direction and the reverse direction as well as zero motion.

Abstract: A method is described for changing gear-ratio by displacing at least one part of the engaging surface of a composite gear (21) and aligning it to the engaging surface of another gear (22), thus permitting a complementary third gear (25) engaged to the engaging surface, to shift from one composite gear to a different composite gear, while being constantly engaged. The method can be employed in a device, which can be used to form a gear-based, continuously engaged, variable transmission. Such a transmission, enhanced by—being combined with a differential assembly and the appropriate gearing, can provide rotational motion at various speeds in one direction and the reverse direction as well as zero motion.