A clamping device for releasably holding a tool holder shank includes a spindle rotatably mounted inside a housing. A drawbar is axially moveable in a bore in the housing between an advanced releasing position and a retracted locking position. A plurality of engagement members are moveable under the effect of the drawbar into locking engagement with the tool holder shank. An actuating sleeve is arranged around a peripheral wall of the spindle and axially moveable in relation to it. A motion transferring mechanism is arranged for transferring an axial movement of the actuating sleeve into a movement of the drawbar. A hydraulic cylinder arrangement is arranged for moving the actuating sleeve. The hydraulic cylinder arrangement includes a cylinder casing fixed to spindle and an annular piston head, which is fixed to or fixedly connected to the actuating sleeve and slidably received in an annular space inside the cylinder casing.

A clamping device for releasably holding a tool holder shank includes a housing, a drawbar axially moveable in a bore in the housing between an advanced releasing position and a retracted locking position, engagement members moveable under the effect of the drawbar into locking engagement with the tool holder shank, and a sleeve arranged around a wall of the housing and axially moveable in relation to it. A first wedge is received in a first aperture in the wall and configured to move the drawbar rearwards in the bore when pressed radially inwards in the aperture by movement of the sleeve in a first axial direction. A second wedge is received in a second aperture in the wall and configured to move the drawbar forwards in the bore when pressed radially inwards in the aperture by movement of said sleeve in an opposite axial direction.

A clamping device has a main body with a bore that extends from a back to a front end thereof. The bore has a fastening area proximate the back end, a front-end axial abutment surface and a central axial abutment surface. A centering sleeve is disposed in the bore and extends axially between a centering sleeve first and second axial end. A guide sleeve is disposed in the bore and partially in the centering sleeve. The guide sleeve extends axially between a guide sleeve first and second axial end. A locking member is removably disposed in the fastening area, has a tapered abutment surface and faces the front end. The centering sleeve is axially retained by and between the tapered abutment surface and the central axial abutment surface. The guide sleeve is axially retained by the tapered abutment surface and the central axial abutment surface.

Provided is a lathe capable of elongating the life of a shifter mechanism. A lathe comprises a spindle, a chucking unit, a power transmitting unit, a shifter, a claw, and a driving unit. The shape of an outer circumference of the shifter in a contact range and a first end of the claw in longitudinal section along the spindle axis is such shape as the acceleration “a” of the first end in the diameter direction with respect to the moving distance of the shifter moving in the direction of the spindle axis (Z-axis direction) at a constant speed is continuous both in a positive range and in a negative range where the contact range is a range of the outer circumference of the shifter in contact with the first end of the claw.

A tool changing mechanism includes a tool base housing, a mandrel disposed therein and having a chamber and a keyway provided axially, and first and second linked units. A first shoulder portion is provided at an end of the keyway, and pulling jaws are disposed at the other end. The first linked unit has a first pulling rod, an end of which has an external thread, and the other end has a connecting portion driven by a pneumatic cylinder. The second linked unit has a second pulling rod, an end of which has an internal thread, and a pressing head is disposed at the other end. The second pulling rod has a sliding key located in the keyway. The first pulling rod is screwed into the second pulling rod, and the relative screwing rotation therebetween attains tool pulling for fixing or tool loosening for removing the cutting tool.

A clamping device is arranged for releasably holding a tool holder shank and includes a housing, a wedge engagement member reciprocally mounted inside the housing, and a wedge having a first pressure receiving surface and first and second wedge surfaces. An aperture extends radially through a wall of the housing and the wedge engagement member extends radially outwards into the aperture. The first wedge surface acts upon a wedge engagement slide surface on the wedge engagement member and the second wedge surface acts upon an aperture slide surface. The wedge is arranged between a surface of the housing and a surface of a member securely arranged to a drawbar to effectuate a displacement of the drawbar when the wedge is moved inwards, to clamp the tool holder shank. A sleeve is arranged around the peripheral surface of the housing for moving the wedge inwards when the sleeve is moved.

A clamping device for releasably holding a tool holder shank includes a spindle rotatably mounted inside a housing. A drawbar is axially moveable in a bore in the housing between an advanced releasing position and a retracted locking position. A plurality of engagement members are moveable under the effect of the drawbar into locking engagement with the tool holder shank. An actuating member is slidably mounted to the spindle. A motion transferring mechanism is arranged for transferring an axial movement of the actuating member into a movement of the drawbar. Two or more hydraulic actuators are arranged in or mounted on the housing on different sides of the spindle and configured to move the actuating member in relation to the spindle. A connecting element forms a connection in radial direction between the actuating member and piston members of the hydraulic actuators.

A clamping device for a tool or workpiece has a draw-in collet and a coupling element. The clamping device has first and second bayonet closures with which the draw-in collet can be locked and braced against the coupling element. The first and second bayonet closures are brought into engagement at the same time, as a result of which the draw-in collet is locked against the coupling element using the first bayonet closure, and the draw-in collet is braced against the coupling element using the second bayonet closure. First, the draw-in collet is pushed into the coupling element with partial actuation of the bayonet closures. Then the draw-in collet is rotated relative to the coupling element with a further partial actuation of the bayonet closures, and finally the draw-in collet is withdrawn to thereby lock the first bayonet closure and to brace the second bayonet closure.

A cutting tool rest includes a first tool holder that holds a rotating tool, a second tool holder that holds a fixed tool, and a plurality of holder-mounting parts on which one of first tool holder and the second tool holder is selectively mounted. Each of first tool holder and the second tool holder includes a clamping mechanism part. Each of holder-mounting parts includes a hydraulic cylinder mechanism part that causes clamping mechanism part to operate in a clamped state of clamping a tool and an unclamped state of unclamping the tool when a hydraulic pressure is supplied.

A facing head as well as a method for inserting a tool into and/or removing a tool from a tool holder device of the facing head. The facing head has a spindle coupling device for exchangeably coupling with a spindle chuck of a working spindle of a machine tool. The facing head has a housing body at which or in which a facing slide is moveably supported in a guided manner. The facing slide supports the tool holder device. The tool holder device is hydraulically controllable. A hydraulic coupling that is mechanically and hydraulically coupled with an associated hydraulic control coupling of the housing body in a tool change position of the facing slide. Remote from the tool change position, the mechanical and hydraulic connection between the hydraulic coupling and the associated hydraulic control coupling is interrupted. In the tool change position a switching of the tool holder device between a hold condition holding the tool and a release condition releasing the tool can be carried out by a respective pressurization with hydraulic pressure.