A lathe includes a spindle, a turret, a Z-axis feed mechanism moving the spindle and the turret relative to each other in a Z-axis direction along a center axis of the spindle, an X-axis feed mechanism moving the spindle and the turret relative to each other in an X-axis direction orthogonal to the Z-axis direction, and a plurality of tool holders each having a tool holding part holding a tool, and attached to the turret. The tool holding part of at least one of the tool holders holds the tool at a holding position thereon set at a position such that, when the held tool is indexed to a machining position by rotation of the turret, a cutting-edge reference point of the held tool is offset to one side with respect to an X-Z plane including a center axis of the turret.

A lathe includes a spindle, a turret, a Z-axis feed mechanism moving the spindle and the turret relative to each other in a Z-axis direction along a center axis of the spindle, an X-axis feed mechanism moving the spindle and the turret relative to each other in an X-axis direction orthogonal to the Z-axis direction, and a plurality of tool holders each having a tool holding part holding a tool, and attached to the turret. The tool holding part of at least one of the tool holders holds the tool at a holding position thereon set at a position such that, when the held tool is indexed to a machining position by rotation of the turret, a cutting-edge reference point of the held tool is offset to one side with respect to an X-Z plane including a center axis of the turret.

A machine tool includes a movement device, which has a first feed shaft and a second feed shaft that mutually intersect, and a plurality of tools, which are driven by the movement device and respective blade edges of which are staggered stepwise. The blade edges of the tools are aligned with the second axis due to the inclination of the tools as a unit. The machine tool is capable of executing center level adjustment of a plurality of tools mounted on a tool post against a workpiece having a larger diameter, and is also capable of reducing wasted time in non-cutting operation via equal stroke lengths of the tools.

A machine tool includes a movement device, which has a first feed shaft and a second feed shaft that mutually intersect, and a plurality of tools, which are driven by the movement device and respective blade edges of which are staggered stepwise. The blade edges of the tools are aligned with the second axis due to the inclination of the tools as a unit. The machine tool is capable of executing center level adjustment of a plurality of tools mounted on a tool post against a workpiece having a larger diameter, and is also capable of reducing wasted time in non-cutting operation via equal stroke lengths of the tools.

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 device for selectively moving a first or second tool relative to a workpiece on a lathe, the device including a first and a second tool providing system, each of the tool providing systems including a guide rail having a length direction, a slide slidably mounted on the guide rail, the slide being shiftable from a waiting position to a work position, a tool retainer on the slide, a block fixed relative to the guide rail, a first lever pivotably mounted to the block, a second lever having a first end pivotably mounted to the block and a second end pivotably mounted to the slide, and a linear actuator having a rod pivotably connected to the first lever, the rod extending in a direction not parallel to the length direction of the guide rail and being shiftable from a first position to a second position.

A device for selectively moving a first or second tool relative to a workpiece on a lathe, the device including a first and a second tool providing system, each of the tool providing systems including a guide rail having a length direction, a slide slidably mounted on the guide rail, the slide being shiftable from a waiting position to a work position, a tool retainer on the slide, a block fixed relative to the guide rail, a first lever pivotably mounted to the block, a second lever having a first end pivotably mounted to the block and a second end pivotably mounted to the slide, and a linear actuator having a rod pivotably connected to the first lever, the rod extending in a direction not parallel to the length direction of the guide rail and being shiftable from a first position to a second position.

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.

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.

An automatic device for locking of tool holders (12) on lathes and machinery performing machining by chip removal, particularly suitable to be used on multi-spindle and single spindle CNC lathes, on transfer machines, milling centres of any kind and, in general, on all types of machine tools which perform machining by chip removal, comprises a support body (14) anchored to the machine tool and surmounted by a plate (16), said device comprises, for each of said tool-holders (12), a pawl (18) provided with a female truncated-cone recess (24), cooperating with a nut screw (36) and moved automatically vertically to engage in contact with a truncated cone collar appendage (40) made in a recess (38) in the rear (12). The movement in the vertical direction of the pawls (18) is produced by means of individual motors (46), equipped with a shaft (48) which protrudes from their lower face and engages to the upper end of said nut screw (36).