A clamping assembly includes a collet adapter and an expansion sleeve movably disposed in collet adapter and a draw pin movably disposed in the expansion sleeve. The expansion sleeve cooperates with the draw pin to define a containment system configured maintain the expansion sleeve within an axial envelope and a radial envelope within the collet adapter. Axial movement of the draw pin in the expansion sleeve within the axial envelope causes a portion of the expansion sleeve to expand radially outward to a predetermined maximum diameter to releasably clamp the collet in the collet adapter.

A load measuring arrangement for a collet assembly is provided. The load measuring arrangement includes a housing having a pocket which includes a first portion and a second portion. The load measuring arrangement further includes a first clamp member having a first groove and a second clamp member having a second groove. The first clamp member and the second clamp member are disposed in the first portion such that the first groove and the second groove together forms a receiving portion. A load measurement device is disposed next to the second clamp member in the second portion such that a load-responsive portion of the load measurement device is configured to be in contact with the second clamp member. The second clamp member is pushed outwards against the load-responsive portion when the receiving portion receives the collet assembly.

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 self-locking clamping system for hollow shaft adapters is proposed.

A load measuring arrangement for a collet assembly is provided. The load measuring arrangement includes a housing having a pocket which includes a first portion and a second portion. The load measuring arrangement further includes a first clamp member having a first groove and a second clamp member having a second groove. The first clamp member and the second clamp member are disposed in the first portion such that the first groove and the second groove together forms a receiving portion. A load measurement device is disposed next to the second clamp member in the second portion such that a load-responsive portion of the load measurement device is configured to be in contact with the second clamp member. The second clamp member is pushed outwards against the load-responsive portion when the receiving portion receives the collet assembly.

Provided is a tool chuck that allows precision gripping of a tool by a collet when this collet is pushed into a chuck body. The tool chuck includes a collet for gripping a tool, a chuck body having, at a leading end thereof, a receiving portion for receiving the collet inserted therein along an axis thereof, a holder containing the collet therein and configured to be movable together with the collet along an axial direction based on the axis, and a nut fitted on the chuck body (2) in a radial direction based the axis and containing the holder in the radial direction. The holder has a movement allowing mechanism for allowing the holder to move relative to the nut along the axial direction when the nut is moved relative to the chuck body along the axial direction.

Disclosed is a tool length adjustment system which allows the tool length to be adjusted without removing the tool from the tool holder. The tool length can be adjusted through the combination of an external circumferential adjustment ring which can be rotated while the tool is in the tool holder, thereby driving an adjustment key built into the tool holder via the use of drive balls which ultimately cause the rotation of the adjustment key.

A clamping assembly includes a collet adapter and an expansion sleeve movably disposed in collet adapter and a draw pin movably disposed in the expansion sleeve. The expansion sleeve cooperates with the draw pin to define a containment system configured maintain the expansion sleeve within an axial envelope and a radial envelope within the collet adapter. Axial movement of the draw pin in the expansion sleeve within the axial envelope causes a portion of the expansion sleeve to expand radially outward to a predetermined maximum diameter to releasably clamp the collet in the collet adapter.

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.