A turning and thread-rolling machine with a pre-compression device includes a fixing base on which the pre-compression device, a fixing mechanism, a guiding base, a processing mechanism assembly, and a control unit are provided, wherein the pre-compression device includes a carrier and at least two cold-rolling heads in order to form by compression a pre-compressed annular groove in a portion of an unprocessed rebar that is adjacent to one end thereof, and, under the control of the control unit, the fixing mechanism clamps the rebar, and the guiding base displaces the processing mechanism assembly to the end of the rebar to perform turning and thread rolling sequentially, thereby processing the end of the rebar into a coupling end. The pre-compressed annular groove facilitates on-site inspection of thread quality and prevents the thread-rolling dies in the processing mechanism assembly from contact with, and hence damage by, the ribs on the rebar.

Embodiments of present disclosure relate to thread machining apparatus (300), method and system. The thread machining apparatus (300) comprises: a spindle motor (310) adapted to drive a thread tool (200) coupled to an output shaft of the spindle motor (310) to rotate at a rotational speed; and a feeding device (320) movably coupled to the spindle motor (310), and configured to drive the spindle motor (310) to move along an axial direction (X) of the spindle motor (310) at a moving speed; wherein during thread machining, the moving speed is proportional to the rotational speed. The solutions of the embodiments of present disclosure have significantly improved the efficiency, stability and accuracy of thread machining.

A turning and thread-rolling machine with a pre-compression device includes a fixing base on which the pre-compression device, a fixing mechanism, a guiding base, a processing mechanism assembly, and a control unit are provided, wherein the pre-compression device includes a carrier and at least two cold-rolling heads in order to form by compression a pre-compressed annular groove in a portion of an unprocessed rebar that is adjacent to one end thereof, and, under the control of the control unit, the fixing mechanism clamps the rebar, and the guiding base displaces the processing mechanism assembly to the end of the rebar to perform turning and thread rolling sequentially, thereby processing the end of the rebar into a coupling end. The pre-compressed annular groove facilitates on-site inspection of thread quality and prevents the thread-rolling dies in the processing mechanism assembly from contact with, and hence damage by, the ribs on the rebar.

A turning and thread-rolling machine with a pre-compression device includes a fixing base on which the pre-compression device, a fixing mechanism, a guiding base, a processing mechanism assembly, and a control unit are provided, wherein the pre-compression device includes a carrier and at least two cold-rolling heads in order to form by compression a pre-compressed annular groove in a portion of an unprocessed rebar that is adjacent to one end thereof, and, under the control of the control unit, the fixing mechanism clamps the rebar, and the guiding base displaces the processing mechanism assembly to the end of the rebar to perform turning and thread rolling sequentially, thereby processing the end of the rebar into a coupling end. The pre-compressed annular groove facilitates on-site inspection of thread quality and prevents the thread-rolling dies in the processing mechanism assembly from contact with, and hence damage by, the ribs on the rebar.

The invention makes available a device for damping the vibrations of a spindle of a machine tool, which spindle rotates about an axis of rotation, which device has a central longitudinal axis that is oriented coaxial to the axis of rotation of the spindle during use, and a housing that is provided for torque-proof coupling to the spindle and delimits a housing space that is configured as a ring space oriented coaxial to the central longitudinal axis and surrounds the central longitudinal axis, a ring-shaped damper mass that is arranged to move in the housing space relative to the central longitudinal axis and oriented coaxial to the central longitudinal axis in the rest state, and includes at least one spring element, by way of which the damper mass is movably held on the housing, with elastic resilience, with reference to the central longitudinal axis of the device, at least in the circumference direction of the damper mass. In that in the case of such a device, according to the invention, a gap is present between a circumference surface of the damper mass and an inner surface of the housing, which gap is filled with a viscous damper fluid, and in that, according to the invention, the clear width of the gap filled with the viscous fluid is adjustable, the damping effect can be adapted to the corresponding requirements in a simple manner.