Abstract: A lathe having a spindle which has a flange for the mounting of a chuck in whose base sliding weights are displaceably mounted in radial grooves and act on the bases of the chuck jaws through rocking reversing pins for the compensation of centrifugal force. To achieve a minimum overhang of the chuck, the lathe is constructed such that the chuck base and the spindle flange are made in one piece, and that the chuck body is fastened releasably on the spindle flange.

Abstract: A deep hole drilling machine having a drill headstock and a drilling carriage, and a drill guide carriage disposed between them, at least two of these three units being displaceable on the machine bed, and the workpiece and/or the drill tube being rotatable. This machine is designed such that differences in workpiece or drill lengths, workpiece inaccuracies and different hole starting and hole finishing movements can be provided for automatically. This is accomplished by providing a length measuring system on each of the displaceable units; the reading made by each measuring system will depend on the position of its unit with respect to a reference point on the fixed unit. A comparator compares the relative positions of the displaceable units, while an evaluating circuit is provided for controlling the movement of at least one of the units on the basis of the readings made after the workpiece and the drill have been inserted into the machine.

Abstract: The invention relates to the positional adjustment of a cutting tool in a machine tool for the purpose of ensuring that the cutting tool is exactly in its correct position prior to starting machining operations. The machine tool is of the kind having a cutting tool support displaceable relative to the bed along two axes which are perpendicular to each other. The apparatus provided for the above purpose in accordance with the invention includes an optical projector producing in a stationary plane a picture of the tip of the cutting tool, including its cutting edge. When the tool support is displaced along either axis, the position of the picture on the plane changes accordingly. A stationary linear array of photosensitive diodes is arranged parallel to one of the axes of displacement of the tool support so that individual diodes will be covered or uncovered by the picture when it travels across the plane upon displacement of the tool support.