FIELD: mechanical engineering, in particular, machine tool manufacture. SUBSTANCE: toothed variable-speed drive has two main gears coupled through gears mesh, self-braking worm gear and non-self-braking transmission. One main gear is connected with driven shaft by Hooke's joint and with self-braking worm transmission. Second main gear is connected with body through mechanism for transmitting force through gears mesh to body for providing rotation of gears mesh point along circle of adjustable radius, and by means of non-self-braking worm transmission - to shafts of worm gears of self-braking worm transmission. Gear ratios of transmissions are selected so as to provide equal angular speeds of main gears. Such construction provides continuous regulation of rotational speed of driven shaft with efficiency equal to that of gear transmissions. EFFECT: increased efficiency, reduced weight and dimensions, enhanced reliability in operation. 5 cl, 8 dwg
