DEVICE FOR SECURING AND RELEASING OF WORKTOOLS IN A WORKTOOL MACHINE SPINDLE

摘要

Electric motor and gearing means for securing and releasing of worktools in the spindle of a machine tool. The motor drives through suitable reduction gearing a planet carrier which is connected simultaneously to two sun gears. One sun gear is connected to a drawbar for screwing and unscrewing same into and off from the tool. The other sun gear is connected to means responding to rotation of said last-named sun gear for applying sufficient tension to said drawbar to set its threads with sufficient force against the threads of the tool to assure against accidental unscrewing of such tool from the drawbar. The parts are arranged so that the first-mentioned sun gear operates to apply said tensioning force sufficient to prevent unscrewing of said tool from the drawbar. Release of the tool is accomplished first by releasing said tensioning force following by unscrewing of the drawbar from the tool.