In one aspect, expansion sleeves for pressure-activated tool holder apparatus are described herein. An expansion sleeve, for example, comprises a first end, a second end and a longitudinal axis extending between the first end and the second end. A first set of fluid chambers are proximate the first end of the sleeve and a second set of fluid chambers are proximate the second end, wherein fluid channels extend along the longitudinal axis to connect radially offset fluid chambers of the first and second sets.

A tool holder having a main body for coupling the tool holder to the spindle of a machine tool and having a damping surface connected thereto for clamping a tool, characterized in that the tool holder has at least one portion shaped in one piece by primary shaping, which in its interior has one or more cavities that form an enclave in the portion shaped by primary shaping.

Tool holder has a first section adapted to be connected to a machining center and a tool holding section comprising a bore with a surface defining an inner diameter of the bore. Dispersed around the surface of the bore and at least partially embedded in the surface of the bore is a joining compound having a Young's modulus greater than a Young's modulus of the surface of the bore.

A tool holder having a main body for coupling the tool holder to the spindle of a machine tool and having a clamping surface connected thereto for clamping a tool, characterized in that the tool holder has at least one portion shaped in one piece by primary shaping, which in its interior has one or more cavities that form an enclave in the portion shaped by primary shaping.

A clamping device for clamping a workpiece to a machine spindle includes at least one clamping bush which extends around a central axis and has at least one clamping surface for the workpiece and at least one clamping body. The clamping bush on a side remote from the clamping surface at least one support surface which extends about the central axis along a helical line. On a side facing, the clamping bush comprises at least one support surface which extends about the central axis along a helical line with a predefined pitch and is inclined at an angle of inclination to a direction axial to the central axis. The clamping body includes a hydraulic chamber in the interior of the clamping body. The clamping device also includes a displacement element, and at least one pressure generator. A clamping force is generatable between the clamping bush and workpiece.

A tool holder includes a main body, a deformable receptacle for clamping a tool, and at least one blocking element which, in order to prevent axial migration of the tool out of the tool holder, is configured to engage in a corresponding counterpart element on the tool and is arranged at the receptacle. In order to allow particularly high concentricity of the tool holder and stable fastening of the clamped-in tool, and at the same time to ensure easy production, the receptacle has two spaced-apart clamping portions, between which the at least one blocking element is arranged.

This invention provides a machine tool capable of easily and quickly attaching/detaching a tool holder while reliably holding the tool holder, including at least two clamp holes (211) that receive pins (203) extending through at least two through holes (202) provided in a tool holder (134), at least two tubular clamp sleeves (302) fitted in the at least two clamp holes (211), respectively, and each including a flexible trunk portion (321), a fluid encapsulating chamber that encapsulates a fluid, a channel extended from the fluid encapsulating chamber to an outer peripheral surface of the flexible trunk portion, and a pressure adjusting portion that adjusts a pressure of the fluid in the fluid encapsulating chamber, wherein a clamp fastening force is made to act on the pins (203) in synchronism with an increase or a decrease in the fluid pressure in the fluid encapsulating chamber.

In one aspect, expansion sleeves for pressure-activated tool holder apparatus are described herein. An expansion sleeve, for example, comprises a first end, a second end and a longitudinal axis extending between the first end and the second end. A first set of fluid chambers are proximate the first end of the sleeve and a second set of fluid chambers are proximate the second end, wherein fluid channels extend along the longitudinal axis to connect radially offset fluid chambers of the first and second sets.

An assembly comprises: a chuck, which has a tool-receiving socket, a contact surface, and a screw thread; and a cutting tool, which has a tool shaft, a mating contact surface, and a mating screw thread. In a clamped state, the mating screw thread of the cutting tool is screwed into the screw thread of the chuck, the mating contact surface of the cutting tool is seated against the contact surface of the chuck, and the tool shaft is frictionally torque-transmittingly clamped in the tool-receiving socket. The invention also relates to a chuck of this type and to a cutting tool of this type.

The invention relates to a hydraulic expansion chuck having an end on the tool side; and an end on the machine side. A shaft is disposed on the end on the machine side for clamping the expansion chuck in a machine tool. An expanding bushing is disposed on the end on the tool side and surrounded by a pressure chamber and can be radially deformed for clamping a tool under the action of a pressure medium received in the pressure chamber.