A tool drive unit for a turning device for machining workpieces has a tool holder driven in a displaceable manner along an infeed direction by a first linear motor and driven in a pendular/displaceable manner in a direction transverse to the infeed direction by a second linear motor. Both linear motors have a moving coil/piezo element. The turning device has a main infeed drive, which produces a primary infeed movement of a turning tool in an infeed direction, and has a main transverse drive which produces a primary transverse movement in a transverse direction transversely to the infeed direction. The turning device has a secondary transverse drive whose movements are oriented in the same direction as the main transverse drive, wherein the turning tool and the axis of rotation can be moved towards one another and away from one another by the superimposition of primary and secondary transverse movements.

A tool carrier assembly for use at a machine tool, which includes at least one workpiece-carrying spindle for rotatably driving a workpiece received in the workpiece-carrying spindle. The tool carrier assembly includes a first slide being movable in a first direction, a tool carrier being supported on the first slide and configured to hold a plurality of tools, a tool drive unit including a tool drive for engaging with one of the plurality of tools held by the tool carrier to rotatably drive said tool, when the tool is arranged at a tool drive position with respect to the tool drive, and a drive mechanism for driving movement of the first slide together with the tool carrier in the first direction relative to the tool drive position, when the tool drive is disengaged with the tool, to relatively move another tool of the plurality of tools into the tool drive position.

A curtain assembly comprises a rotatable drive element wherein at least one helical guide structure is formed on, or into, the outer surface of the drive element. A drive attachment element having a structure that communicates with the helical guide structure to move the drive attachment element axially along the drive element when the drive element is rotated. Specific embodiments incorporate either a manual or motor-driven rotation assembly for rotating the drive element. Further specific embodiments involve a helical guide structure that comprises a helical groove and a structure that comprises a tooth that engages with the helical groove.

A curtain assembly comprises a rotatable drive element wherein at least one helical guide structure is formed on, or into, the outer surface of the drive element. A drive attachment element having a structure that communicates with the helical guide structure to move the drive attachment element axially along the drive element when the drive element is rotated. Specific embodiments incorporate either a manual or motor-driven rotation assembly for rotating the drive element. Further specific embodiments involve a helical guide structure that comprises a helical groove and a structure that comprises a tooth that engages with the helical groove.

A motorized drapery system having an elongated rotating drive element that has a non-circular cross-sectional shape such as square, rectangular, trapezoidal, cross shaped or any other non-circular shape that is twisted. In one arrangement the drive element is twisted in one direction along its entire length. In another arrangement the drive element is twisted in one direction in a first section and twisted in an opposite direction in a second section thereby providing a center opening/center closing drapery. A plurality of rings are positioned around the drive element including at least one driver ring that includes a feature that connects to the drive element and is configured to facilitate movement along the drive element, and a plurality of idler rings that are configured to slide along the drive element. A curtain is connected to the rings and opens and closes as the rings move along the drive element.

A motorized drapery system having an elongated rotating drive element that has a non-circular cross-sectional shape such as square, rectangular, trapezoidal, cross shaped or any other non-circular shape that is twisted. In one arrangement the drive element is twisted in one direction along its entire length. In another arrangement the drive element is twisted in one direction in a first section and twisted in an opposite direction in a second section thereby providing a center opening/center closing drapery. A plurality of rings are positioned around the drive element including at least one driver ring that includes a feature that connects to the drive element and is configured to facilitate movement along the drive element, and a plurality of idler rings that are configured to slide along the drive element. A curtain is connected to the rings and opens and closes as the rings move along the drive element.

A machine tool, in particular multi-spindle turning machine, comprising a machine frame, a turret body being rotatably supported by the machine frame, a plurality of workpiece spindles being arranged on the turret body, each of the workpiece spindles having a workpiece receiving portion for receiving a respective workpiece on one side of the turret body facing a working space of the machine tool, and a plurality of tool post assemblies supported by the machine frame around the turret body, wherein each tool post assembly includes a tool post having one or more tool cartridge receiving openings respectively being configured to detachably receive a tool holder cartridge TC holding a tool.

A machine tool, in particular multi-spindle turning machine, comprising a machine frame, a turret body being rotatably supported by the machine frame, a plurality of workpiece spindles being arranged on the turret body, each of the workpiece spindles having a workpiece receiving portion for receiving a respective workpiece on one side of the turret body facing a working space of the machine tool, and a plurality of tool post assemblies supported by the machine frame around the turret body, wherein each tool post assembly includes a tool post having one or more tool cartridge receiving openings respectively being configured to detachably receive a tool holder cartridge TC holding a tool.

A cutter holder has a holder, a collet, and a nut. The holder has a first threaded portion having an external thread, a first abutting surface, a second abutting surface, at least one recess, and at least one sealing member. The at least one recess is recessed in the second abutting surface. The at least one sealing member is mounted in the at least one recess and partially protrudes from the second abutting surface. The nut has a second threaded portion having an internal thread, a third abutting surface, and a fourth abutting surface. The internal thread and the external thread are corresponding internal and external trapezoidal threads, respectively. The third abutting surface and the first abutting surface have a corresponding diameter with a clearance therebetween being less than 0.015 millimeter. The fourth abutting surface and the at least one sealing member are in an interference fit.

A device for holding tools for machine tools, includes at least one interchangeable holder and one base holder. Each interchangeable holder includes two interchangeable-holder guiding elements which are engaged with base-holder guiding elements of the base holder. Furthermore, each interchangeable holder comprises an interchangeable-holder coolant channel comprising an interchangeable-holder coolant-channel opening in one of the interchangeable-holder guiding elements, which comes into contact with a base-holder coolant-channel opening of a base-holder coolant channel, which is arranged on a base-holder guiding element. First guiding elementseither the interchangeable-holder guiding elements or the base-holder guiding elementshave a convex semicircular cross-section. The cross-section has a flat area containing the vertex of the semicircle, or it has two widened areas which are arranged in mirror symmetry on the semicircle. The guiding elements that engage with the first guiding elements have a concave circular-sector-type cross-section with a central angle of less than 180.