Abstract: The guide bushing (1) for a machine tool, especially for an automatic lathe, includes at least two segments (2), each segment being connected on both sides to a neighboring segment by an elastic means (3) in order to form an axisymmetric body of axis (1A) and has a central opening (10) enabling a bar to be machined to pass through, each of the elastic means (3) extends axially along the axis (1A) in a groove (8) of the guide bushing.

Abstract: The guide bushing (1) for a machine tool, especially for an automatic lathe, includes at least two segments (2), each segment being connected on both sides to a neighboring segment by an elastic means (3) in order to form an axisymmetric body of axis (1A) and has a central opening (10) enabling a bar to be machined to pass through, each of the elastic means (3) extends axially along the axis (1A) in a groove (8) of the guide bushing.

Abstract: In a spindle assembly for machine tools, the axial length ? of the collar of a spring collet is determined as a function of the axial course length c of a clamping sleeve operating spring collet. This axial length ? is preferably retained within an interval ranging between 3 mm and 9 mm. A tapering surface of the collar presents an inclined profile, which is straight, curved, or at least partially curved. The angle of inclination formed by the tapering surface with the axis of the spring collet is advantageously of the order of 45°. The spring collet has at least two grooves. The gap between these grooves may be determined in such a way that, when the spring collet is in the closed position, then the workpiece is gripped with a predetermined clamping force, and the two mutually opposing faces of each groove portion abut against each other.

Abstract: In a spindle assembly for machine tools, the axial length ? of the collar of a spring collet is determined as a function of the axial course length c of a clamping sleeve operating spring collet. This axial length ? is preferably retained within an interval ranging between 3 mm and 9 mm. A tapering surface of the collar presents an inclined profile, which is straight, curved, or at least partially curved. The angle of inclination formed by the tapering surface with the axis of the spring collet is advantageously of the order of 45°. The spring collet has grooves, the number whereof is at least two, but also greater than three. The gap between these grooves may be determined in such a way that, when the spring collet is in the closed position, then the workpiece is gripped with a predetermined clamping force, and the two mutually opposing faces of each groove portion abut against each other.

Abstract: An internal surface chucking mechanism (ISM) for gripping and for releasing an internal surface of a workpiece (W) in process on a processing machine is configured for reversible exchange with an external surface chucking mechanism (EXS) dedicated to grip an external surface of the workpiece. The ISM fits machinery where the workpiece is rotating and is non-rotating, in a first mode with the EXS, and in a second mode with the ISM, and vice-versa. A fluid conduit inside the ISM provides fluid, such as oil, for exhaust adjacent and opposite the workpiece. An appropriately oriented exit outlet (353) directs a stream of fluid to impinge on the workpiece, to eject it from the ISM when released from grip. The fluid cools and lubricates both the ISM and the workpiece.