Abstract: In order to improve a machine tool with a motor spindle, including a main motor integrated into a work spindle coaxially with the spindle axis, the main motor, for its part, comprising a rotor and a stator, and with a cooling device for supplying cooling surfaces of the main motor with a gaseous coolant, so that simple and effective cooling of the main motors of the motor spindles is possible, it is proposed that the stator be comprised of stator plates which, for their part, form cooling surfaces, and that the gaseous coolant be conducted directly along the cooling surfaces of the stator plates.

Abstract: In order to improve a machine tool comprising at least one hydraulic drive for working motion or rapid motion operation connected via a supply pipe to a high-pressure network supplied by a high-pressure pump so that the drives can be operated with high pressure for working motion and to a substantial degree with low pressure for rapid motion, it is proposed that a low-pressure network supplied by a low-pressure pump be provided for operating the drive for rapid motion, that a flow-limiting member be arranged between the high-pressure network and the supply pipe for bringing about a pressure drop in the supply pipe during the rapid motion by limiting the flow of a hydraulic medium under high pressure and for maintaining the high pressure to a substantial degree during the working motion, and that the low-pressure network be connected to the supply pipe via a check valve which is open on account of the pressure drop during the rapid motion and closed during the working motion.

Abstract: Process for loading and unloading the main spindle of a lathe which comprises a turret provided with at least two drivable auxiliary spindles and which is combined with a workpiece handling device, wherein in order to shorten the machining time, the rotating main spindle is loaded and unloaded with the aid of the auxiliary spindles driven at the same rotational speed as the main spindle, and the auxiliary spindles are loaded and unloaded by the workpiece handling device when they point in the upward direction.

Abstract: Lathe comprising a main work spindle drivable by numerical control and a turret with several indexing stations, the turret having at least one drivable tool spindle, being mounted on a turret slide for rotation about a turret axis and being rotatable by numerical control about this axis by means of a turret driving device, and also comprising a switchable device for securing the turret against rotation. For positive locking of the turret and for play-free mounting of the unlocked turret, spur gears displaceable relative to one another in the direction of the turret axis are connected to the turret and to the turret slide in a rotationally fixed manner, and a bearing is provided for the turret which in the unlocked state of the latter is free from play.

Abstract: A lathe comprises two turrets each arranged on a compound slide system. The turrets are mounted on sides of the two compound slide systems facing each other and have indexing axes extending parallel or at a slight incline to the work spindle axis of the lathe. To reduce the danger of collisions between the two turrets and to enable the two turret bodies to be moved close together, the turret body located on the headstock side is smaller and has less stations than the other turret body with the result that the circles described by the tool cutting edges during rotation of the two turrets are smaller in the case of one turret than in the other.

Abstract: The invention relates to a method for checking performance of the cutting-off operation on automatic lathes for working bar material or the like. In accordance with the invention, operating conditions are initiated at the end of a prescribed time interval for the cutting-off operation which result in relative rotation of the spindles in opposite directions in the event that the material has been completely severed at the cutting-off point. A discrepancy between the specified and the actual relative rotation is interpreted as a system failure due to the presence of a material link at the cutting-off point, whereupon a corresponding error signal is triggered.

Abstract: A workpiece handling device comprising a carrier mounting a plurality of pivot levers, each of which holds a clamping element. The pivot levers are pivotable about axes extending parallel to one another and their clamping elements are adapted to be synchronously moved towards and away from one another by a drive means common to all the pivot levers. In order to be able to move the clamping elements exactly in radial directions and in straight lines relative to the center of the workpiece and, at the same time, covering a large circular area, it is suggested that a clamping lever bearing the clamping element be articulatedly mounted on each pivot lever pivotable by the common drive means and that a pivoting device engaging each clamping lever be provided for pivoting the clamping lever in relation to the pivot lever in response to the pivoting movement thereof such that the clamping elements move in a manner known per se along straight lines intersecting at a center.

Abstract: A pressure regulator for hydraulically controlled machine tools comprises a first directly controlled three-way pressure-regulating valve with which required work pressure can be set by a machine control system. In addition to a first surface, the control spool is provided with a second surface to which hydraulic fluid under the pressure at the pressure port can be applied by means of an externally controllable valve. This results in an additional force acting upon the control spool in the direction opposite to, or in the direction of, the force exerted by the elastic element on the control spool.

Abstract: Multiple-spindle lathe with a drive shaft which is rotatably and longitudinally displaceably mounted in a headstock, a spindle carrier which is mounted on the headstock for rotation about an indexing axis, and several work spindles which are rotatably mounted in the spindle carrier and comprise at their outer ends chucks and at their inner ends coupling elements for coupling one respective work spindle with the drive shaft.

Abstract: The invention relates to a feeding device for a tool slide of a machine tool of a simple, compact and economical construction comprising an electro-hydraulic linear amplifier easily accommodated in the constructional space of a hydraulically operated tool slide. The valve housing is inserted into the piston rod on the side of the piston remote from the control valve means thereby allowing for a plurality of tool slides to be arranged in a very compact space. The valve means forms a cartridge which can be simply inserted into the cylinder chamber formed by the cylinder housing. The arrangement of the control valve means in the cylinder housing and the rigid connection between the motor and the piston result in compact design and in shorter conduits for the hydraulic fluid between the control valve means and the cylinder chambers thereby leading to a high rigidity of the feeding device.

Abstract: A tool changing apparatus for a machine tool comprising, adjacent an operating space, an indexable tool carrier displaceable in two feed directions defining a plane of movement and comprising a plurality of tool receiving means each including a holding means, which is provided with a clamping device, for inserting and securely clamping a base of a tool as well as a clamping element having a predetermined direction of movement for tightening and releasing the clamping device, and also comprising a tool gripping device having an actuating device adapted to be coupled to the clamping element.

Abstract: A tool carrier for lathes, in particular a tool turret, having a plurality of stations for holding tools, at least one of which is provided with a driven tool spindle designed as a hollow shaft and rotatably mounted in a housing. This tool spindle accommodates a tool chuck which is coaxial to and non-rotatably connected with the tool spindle and is displaceable in axial direction relative to the tool spindle for opening and closing. The tool carrier also has a threaded spindle connected in axial direction with the chuck and a nut arranged thereon for opening and closing the chuck. To simplify the construction only one drive shaft is provided and this shaft is constantly coupled with the nut and connected with the tool spindle via a releasable coupling.

Abstract: Device for changing the attachment jaws of a chuck provided with main jaws, each of which has two axially aligned bolts for exact positioning of the attachment jaws. These bolts engage and fit into bores in the attachment jaw and guide a locking slide means which is displaceable in a radial direction by means of a headless screw inserted into the attachment jaw. A gripping device for the atachment jaws has a screw driving means and a threaded bore for the screw and so the latter is screwed partially out of the attachment jaw and into the gripping device in order to connect gripping device and attachment jaw with one another.

Abstract: The invention relates to a chuck in which the clamping jaws are connected with the chuck body via radially deflectable arms. Two flat parallel arms are preferably provided for each clamping jaw. These arms act like leaf springs and form a parallelogram link arrangement for the associated clamping jaw. The clamping jaws and arms are preferably designed in one piece with the chuck body by forming slots in corresponding projections of the chuck body by means of wire erosion. The clamping jaws are actuated in accordance with the invention via a wedge face arrangement comprising a two-armed lever for each clamping jaw. A short arm of the lever engages the associated clamping jaw whereas a wedge face provided on a distinctly longer arm of the lever interacts with an actuating element, in particular a roller, of the axially displaceable actuating member.

Abstract: The invention relates to a multiple-spindle automatic lathe with several work spindles. In accordance with the invention, each of the work spindles comprises an associated electric motor. Associated with the electric motors are supply devices with at least one stationary means fed from an external voltage source and at least one rotatable means cooperating therewith. Also provided are speed and position control devices comprising per work spindle one rotary angular position detector means each for absolute value angle coding including a detector rotating synchronously with the work spindle and a stationary sensor means.

Abstract: A method of machining a workpiece, which is rotatable about a first axis, by a tool pivotable about a second axis parallel to the first axis and drivable about a third axis perpendicular to the second axis. To allow the circumference of the workpiece to be machined off-center without the necessity of moving the first or the second axis transversely to the plane defined by these two axes, the workpiece and the tool are rotated or pivoted about the first or second axis, respectively, at the same time, in the same direction and at the same angular velocity and, simultaneously, the second axis is displaced transversely to the first axis at such a velocity that the equation X.sup.2 =Y.sup.2 +A.sup.2 always applies, wherein X is the distance of the second axis from the first axis, Y is the distance of the first axis from the plane defined by the second and third axes and A is the distance of the second axis from the vertical projection of the first axis onto this plane.

Abstract: A clamping mechanism for mounting a tool holder or receiving sleeve having a cylindrical outer contour to a machine tool having a bed, the clamping mechanism comprising a slide mounted for sliding movement on the bed and having a concave surface for supporting the cylindrical outer contour of the tool holder sleeve, an apparatus for securing the slide on the bed, and a clamp assembly including a clamping bracket circumferentiallyspanning the tool holder sleeve, an arrangement for detachably securing the clamping bracket to the slide, and a threaded structure for tightening the clamping bracket around the tool holder sleeve.

Abstract: Multispindle-automatic turret lathe comprising a spindle support which is rotatable about a central switching or indexing axis and in which are rotatably mounted a number of work spindles each defining one switching or indexing station of the spindle support.In order to enable the tools which are fitted on the turret being precisely measured in that position thereof in which the tools are required to work a measuring station is provided on the spindle support in like geometrical relation to the indexing axis as the workspindles, said measuring station defining a further switching or indexing station of the spindle support.

Abstract: Method for producing threads and machine tool for thread milling, wherein in order to avoid high cutting speeds and also to produce short millings, a milling cutter is used, which comprises several teeth forming at least one thread, rotates at the point of engagement in the opposite direction to the workpiece, encompasses the latter during the production of an external thread with substantial radial play or in the production of an internal thread is encompassed by the workpiece with substantial radial play, and wherein the advance s of the milling cutter meets the following condition:s=h.multidot.(1-i)with h representing the pitch of the thread to be produced and i the rotational speed ratio of milling cutter and workpiece differing from 1.

Abstract: Automatic turret lathe with a synchronous spindle in the tool turret which is drivable in synchronism with the main spindle and comprises a workpiece chuck means. To enable workpieces to also be worked on the rear side, i.e., on the side on which they were severed from a stock rod, while the next workpiece held in the main spindle is already being machined with the aid of a further tool carrier, a third tool carrier is arranged on the side of the tool turret mounted on a compound slide system facing away from the main spindle.