When a wheel clamp is used, width of a wheel is detected first, a first servo motor drives a lead screw to rotate, a supporting block and a lifting plate are automatically adjusted to appropriate heights via a nut, a manipulator puts the wheel onto end face blocks, air-tight devices are pressed down, an oil cylinder drives a chuck so that clamping jaws expand the central hole of the wheel, meanwhile, four air cylinders drive clamping blocks to compact outer side of the wheel, and the wheel is completely positioned; at this moment, a bolt hole of the wheel can be drilled; after machining, second servo motor drives right shaft, right lug plate and a turnover part to rotate certain angles via second decelerator; high pressure oil is introduced into cavities between ipsilateral expansion sleeves and end covers, and left and right shafts are separately locked by ipsilateral expansion sleeves.

A clamping device (100) includes a first movable member (210) that is movable along an extending direction of a first body interior space (120), a disc spring (260), an annular spring (270), a spring (280) and a collet (300). A driving mechanism (400) has a second movable member (430) that moves along an extending direction of a second body interior space (130) with rotation of a rotary member (410). When the rotary member is rotated in one direction, the first movable member moves toward an oil-filled closed space (121) and the clamping device is set to a clamping mode that will hold a tool holder (510). On the other hand, when the rotary member is rotated in the opposite direction, the first movable member moves towards the side opposite of the oil-filled closed space and the clamping device is set to an unclamping mode that will release the tool holder.

A spindle apparatus for use at a machine tool, having: an assembly including a workpiece spindle to receive an elongated workpiece and a motor for driving spindle rotation of the workpiece spindle about a spindle axis; a rotary guide-bush assembly being axially arranged with the workpiece spindle with respect to the spindle axis, the rotary guide-bush assembly receiving the elongated workpiece supported at the rotary guide-bush assembly to rotate about the spindle axis enabling movement of the elongated workpiece; wherein the rotary guide-bush assembly includes a portion to clamp the elongated workpiece, received in the rotary guide-bush and in the workpiece spindle, to transfer driving torque applied from the spindle motor during a driven acceleration of the rotation through the clamped elongated workpiece for rotation of the rotary guide-bush synchronized with the driven acceleration of the rotation of the workpiece spindle.

A spindle apparatus for use at a machine tool, in particular a lathe, has: a spindle assembly including a workpiece spindle to receive an elongated workpiece and a spindle motor for driving spindle rotation; and a rotary guide-bush assembly axially arranged with the workpiece spindle, the rotary guide-bush assembly including a rotary guide-bush to receive the elongated workpiece and supported at the rotary guide-bush assembly to rotate with the elongated workpiece received in the workpiece spindle about the axis while enabling a movement of the elongated workpiece in the axial direction. The spindle and rotary guide-bush assemblies connect to each other by a torque transferring connection, between the spindle and rotary guide-bush assemblies along the axis to transfer driving torque during acceleration or deceleration of the spindle rotation driven by the spindle motor to the rotary guide-bush of the rotary guide-bush assembly.

A hydraulic chuck includes a chuck body, a fixed seat, a rotary seat and a plurality of flexible seal members. The fixed seat is fixedly mounted to the chuck body. The rotary seat is rotatably mounted to the fixed seat and cooperates with the fixed seat to define a gap therebetween. Each of the seal members has a first annular segment fixedly mounted to the fixed seat, a neck segment extending from the first annular segment and through the gap, and a second annular segment connected to an end of the neck segment distal from the first annular segment, and disposed adjacent to the rotary seat.

A hydraulic chuck includes a chuck body, a fixed seat, a rotary seat and a plurality of flexible seal members. The fixed seat is fixedly mounted to the chuck body. The rotary seat is rotatably mounted to the fixed seat and cooperates with the fixed seat, to define a gap therebetween. Each of the seal members has a first annular segment fixedly mounted to the fixed seat, a neck segment extending from the first annular segment and through the gap, and a second annular segment connected to an end of the neck segment distal from the first annular segment, and disposed adjacent to the rotary seat.

A clamping device for releasably holding a tool holder shank includes a spindle rotatably mounted inside 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, an actuating member slidably mounted to the spindle, a motion transferring mechanism for transferring an axial movement of the actuating member into a movement of the drawbar, and a cylinder housing and an associated piston member for moving the actuating member in relation to the spindle. The cylinder housing is arranged in the housing in an axially floating manner. The actuating member is rotatable in relation to the cylinder housing and the piston member together with the spindle.

A counter bearing for machining spindles of machine tools has at least one expansion bushing with an elastically deformable wall that delimits at least one pressure chamber. The pressure chamber accommodates a pressure medium. A supply line for the pressure medium opens into the pressure chamber. A pressure conduit opens into the pressure chamber. A mechanically actuatable pressure element is disposed in the pressure conduit and actuated by an actuating tool. A piston is slidably arranged in the pressure conduit and actuated by the pressure element, wherein the piston loads the pressure medium.

An air chuck includes: a finger support part including a pair of fingers and a pair of lock shafts; a chuck main body part including an operation mechanism operable to open and close the fingers; and linking mechanisms that detachably link the finger support part to the chuck main body part. Each of the linking mechanisms causes the corresponding lock shaft to shift to a non-lock position so as to render the pair of fingers capable of being opened and closed when the finger support part is linked to the chuck main body part. Each of the linking mechanisms causes the corresponding lock shaft to shift to a lock position and locks the pair of fingers so as to render the pair of fingers incapable of being opened and closed when the finger support part is detached from the chuck main body part.

A clamping device is arranged for releasably holding a tool holder shank. The clamping device includes a housing, a drawbar axially moveable in a bore in the housing in a first axial direction 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, a sleeve-shaped actuating member surrounding a part of the drawbar and axially moveable in relation to it, a piston received in the bore and fixed to the actuating member, and a wedge arranged on the outside of the drawbar and configured to move the drawbar rearwards in the bore when pressed inwards towards a longitudinal center axis of the drawbar by movement of the piston and the actuating member in the first axial direction.