A low-frequency vibration machining center includes a cam, a transmission shaft, a roller, a tool holder, a driven follower, and an elastic member. An end of the transmission shaft is coaxially connected to the cam, and another end is provided for connecting to a driving device, which is adapted to drive the transmission shaft and the cam to rotate about a first axial direction. The roller is disposed at a position where the roller touches a cam surface of the cam. A second axial direction is defined to be perpendicular to the first axial direction. The roller and the tool holder are disposed at two opposite sides of the driven follower, respectively. The elastic member provides an elastic force to keep the roller being in contact with the cam surface. When the cam is rotated, the roller is pushed to move the driven follower and the tool holder in the second axial direction.

A workpiece holding device for holding a workpiece in a heat treatment system while the workpiece undergoes a thermal expansion and/or contraction includes at least two clamping units configured to apply a radial and/or an axial clamping force to the workpiece to hold the workpiece in the workpiece holding device in a predefined position, and at least three support units configured to support the workpiece. A first one of the at least three support units includes a first cylinder configured to support the workpiece, the first cylinder having a longitudinal axis and being configured to rotate around the longitudinal axis.

A workpiece holding device for holding a workpiece in a heat treatment system while the workpiece undergoes a thermal expansion and/or contraction includes at least two clamping units configured to apply a radial and/or an axial clamping force to the workpiece to hold the workpiece in the workpiece holding device in a predefined position and a drive unit configured to rotate the workpiece in the workpiece holding device. The at least two clamping units may be configured to adjust their position relative to the holding device to maintain the clamping force during the thermal expansion and/or contraction of the workpiece.

A workpiece holding device for holding a workpiece in a heat treatment system while the workpiece undergoes a thermal expansion and/or contraction includes at least two clamping units configured to apply a radial and/or an axial clamping force to the workpiece to hold the workpiece in the workpiece holding device in a predefined position, and at least three support units configured to support the workpiece. At least one of the support units includes a carrier and an exchangeable support element attached to the carrier, the exchangeable support element being configured to contact and rotatably support the workpiece in the predefined position.

A chucking apparatus for chucking an object contains a basic body which has a receiving space in which the object can be disposed. A chucking device is provided with a chucking nut which is screwable onto the basic body and by the chucking nut being screwed onto the basic body the object disposed in the receiving space can be chucked non-rotatably. The chucking nut has a plurality of roller bodies having a defined roller engagement structure. The roller bodies are held in an axially rotatable manner on a chucking body of the chucking nut and are arranged distributed in the circumferential direction on the chucking nut. The rollers by their roller engagement structure are in engagement with the basic body engagement structure of the basic body.

A lathe capable of shortening a spindle with respect to a spindle axis direction. A spindle provided with a chuck at the front end thereof is rotatably supported on a support by bearings. A chuck operating apparatus includes a tilt claw and a shifter. A built-in motor is disposed between the bearings to rotate the spindle. The claw is provide outside the spindle and between the bearings. The claw has a movable end whose distance from the spindle axis varies between a first posture to bring the chuck into the opened state and a second posture to bring the chuck into the closed state. The shifter is provided outside the claw and movable in the spindle axis direction to be brought in a first position to bring the claw into the first posture and in a second position to bring the claw into the second posture.

A chuck operating apparatus includes a claw, a shifter, and a shifter drive unit. The rotatable claw has a first posture to bring the chuck into the opened state and a second posture to bring the chuck into the closed state. The rotatable shifter is brought in a first position to bring the claw into the first posture and in a second position to bring the claw into the second posture. The shifter drive unit has a shifter lever having an insertion part provided with a shifter bearing capable of being brought into contact with a side surface of an outward groove of the shifter. A roller is provided on one of the claw and the shifter in a contact position with the other to roll in a spindle axis direction and a groove is formed on the other to receive the roller when the chuck is in the opened state.

A lathe capable of facilitating maintenance of a chucking mechanism. A chuck operating apparatus includes a claw and a shifter to open and close a chuck provided on a spindle. The tilt claw provided outside the spindle has a first posture to bring the chuck into the opened state and a second posture to bring the chuck into the closed state. The shifter provided outside the spindle and movable in a spindle axis direction is brought in a first position to bring the claw into the first posture and in a second position to bring the claw into the second posture. A roller is mounted on the shifter in a contact position with the claw to roll in the spindle axis direction.

A hole inner-surface cutting apparatus includes a working head composed of a rotatable body having a cutting tool and a main body, a rotation rod for rotating the rotatable body, and a stroke rod for stroking the working head. At least three positioning mechanisms for positioning the working head along a radial direction in the penetrating hole is provided on the main body. Each of the positioning mechanisms has three sliders arranged radially, guide rollers respectively disposed on distal ends of the sliders, a piston for pressing the sliders radially outward, and a fluid pressure chamber for actuating the piston. Further provided is a controller for controlling fluid pressures in the fluid pressure chambers of the positioning mechanisms independently from each other.

A chucking apparatus for chucking an object contains a basic body which has a receiving space in which the object can be disposed. A chucking device is provided with a chucking nut which is screwable onto the basic body and by the chucking nut being screwed onto the basic body the object disposed in the receiving space can be chucked non-rotatably. The chucking nut has a plurality of roller bodies having a defined roller engagement structure. The roller bodies are held in an axially rotatable manner on a chucking body of the chucking nut and are arranged distributed in the circumferential direction on the chucking nut. The rollers by their roller engagement structure are in engagement with the basic body engagement structure of the basic body.