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 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 releasably holding a tool holder shank includes a housing, a drawbar axially moveable in a bore in the housing, engagement members moveable under the effect of the drawbar into locking engagement with the tool holder shank, and an actuating member rotatably arranged in the bore. Upon rotation of the actuating member, a contact surface on a motion transferring element fixedly connected to the actuating member achieves an axial movement of the drawbar by pressing against a contact surface on another motion transferring element fixedly connected to the drawbar. At least one of the contact surfaces includes two sections with mutually different pitch, such that the same angular displacement of the actuating member, when rotated in a first rotary direction, results in a longer axial movement of the drawbar in a first phase of the rotary movement than in a final phase thereof.

A clamping device for releasably holding a tool holder shank is formed with an engagement bore in a rear end, and includes a housing having a bore in a forward end for receiving the tool holder shank, a drawbar reciprocally movable inside the housing and which in a forward end is provided with engagement means arranged to engage with an engagement formation inside the engagement bore of the tool holder shank, and which is formed with a drawbar aperture extending through the drawbar in a transverse direction of the same, and a cam shaft extending through the drawbar aperture. The cam shaft includes three cam formations and more precisely first and second spaced apart cam formations, which are journalled in seating apertures in the housing on opposite sides of the drawbar, and an intermediate third cam formation located between the first and second cam formations and positioned within the aperture of the drawbar. The drawbar is insertable into the bore from the forward end.

A rotating-tool main shaft includes a hollow ram, a hollow main shaft, a collet, a draw bar that moves the collet in the axial direction, a hydraulic cylinder that moves forwardly the draw bar, and a disc spring that moves backwardly the draw bar. The draw bar includes a spring catch which is retained in the hollow main shaft so as to be movable, and which catches the disc spring. The disc spring is placed in the hollow main shaft, and is placed within a distance that is at least a half of a distance from a tip of the draw bar to the spring catch in the axial direction.

A clamping assembly includes a base member having an internal bore, a lock rod within the internal bore of the base member and moveable in a forward direction and rearward direction between an unlocked position and a locked position, a crank wheel having an axis of rotation, and a linkage coupled to the lock rod and coupled to the crank wheel at a position radially offset from the axis of rotation of the crank wheel.

An ultrasonic spindle device with automatic tool changer is disclosed. The ultrasonic spindle device includes a housing member having an inner space along a longitudinal direction, a shaft member rotatably disposed in the inner space and having a hollow portion, an ultrasonic oscillation member disposed in the hollow portion and having a through hole, a drawbar member disposed in the hollow portion to move in a front-rear direction, a portion of the drawbar member being inserted into the through hole and passing through the ultrasonic oscillation member, a clamping member connected to a front end of the drawbar member and clamping a tool, a portion of the clamping member being disposed outside the housing member, a rotation means rotating the shaft member, and a cylinder member moving the drawbar member forward or backward along a longitudinal direction of the shaft member.

Disclosed is an interchangeable gripper head including: a body defining a longitudinal axis, including a first end intended to be fitted into a nut and a second, free end provided with sectors capable of elastic deformation in a radial direction and intended to receive a removable head; a thrust pin mounted so as to slide along the longitudinal axis inside the body, in a first direction under the effect of a driving force transmitted through the nut by a kinematic connector and in a second direction under the effect of a spring member; and lugs integrally mounted and in a regular angular arrangement on the thrust pin and protruding radially from the surface of the thrust pin through the body of the gripper. The lugs are fixedly arranged in a longitudinal and radial position on the thrust pin by a fixing unit.

Disclosed is a machine tool ELECTRICAL DRIVING SYSTEM capable of selectively transmitting power of a motor for driving a spindle in a lathe which machines a workpiece to a rotation system including a drawbar and a spindle for driving a chuck, using a clutch mechanism. The machine tool ELECTRICAL DRIVING SYSTEM includes a housing, a hollow tubular spindle rotatably installed inside the housing, a drive pulley rotatably installed with respect to the spindle outside the spindle, a spindle motor, a drawbar installed to be linearly movable with respect to the spindle but non-rotatable relative to the spindle, a motion conversion unit configured to convert a rotary motion of the drive pulley into a forward-rearward linear motion of the drawbar, a clutch unit, a position detection unit configured to the drive pulley to detect an amount of rotation and a rotation position of the drive pulley, and a controller.

A clamping assembly includes a base member having an internal bore, a lock rod within the internal bore of the base member and moveable in a forward direction and rearward direction between an unlocked position and a locked position, a crank wheel having an axis of rotation, and a linkage coupled to the lock rod and coupled to the crank wheel at a position radially offset from the axis of rotation of the crank wheel.