An automatic lathe includes a main spindle that rotates a workpiece about a shaft center, a cutting tool that processes the workpiece, a feeder that moves the cutting tool, an input receiver that receives inputs regarding an eccentric distance and a radius, and a controller that controls the movement by the feeder such as to set a virtual circle having a radius of the distance, to set an offset virtual circle having a center at a position where a center of the virtual circle is offset from the shaft center of the workpiece in the radial direction of the workpiece by the radius, and to move the cutting tool along an circumference of the offset virtual circle in relation to a rotation of the workpiece by the main spindle. A hole is processed, which has the radius at a position away from the shaft center by the distance.

A method for controlling a level of screwing quality of a screwdriver relative to a predetermined screwing objective. The method includes: obtaining, at a predetermined angular frequency, a series of doublets representative of a rise in screwing torque for at least one screw, constituting a first table of values, each doublet including an angle value and a torque value; determining, from the first table, a second table of values presenting the torque as a function of the angle and being representative of the true characteristic of the at least one screw; determining a third table of values, presenting the torque as a function of the angle and being representative of disturbances induced by the screwdriver during the rise in torque, from the first and second tables; analysis of the third table, delivering information representative of a dispersion and/or a deviation relative to the screwing objective, resulting from the screwdriver-induced disturbances.

A numerical controller can suppress overshoot in adaptive control and includes a speed calculation unit and a spindle load correction unit. The speed calculation unit performs PID control to adjust a feeding speed based on a spindle load measured by a measurement unit. The spindle load correction unit corrects the spindle load so as to have a value close to a target load until the spindle load reaches the target load. The speed calculation unit performs PID control using the corrected spindle load.

A machine tool includes a workpiece holder, a tool holder holding working tools that includes a hob cutter used in a rough machining and a skiving cutter used in a finish machining, a tool magazine, a tool replacing device replacing one of the working tools mounted on the tool holder with the other of working tools housed in the tool magazine, a rough machining controlling section performing the rough machining on the workpiece, a tool measuring device measuring a position of a blade in a rotation direction of the skiving cutter, an angle correcting section correcting a rotation angle of the skiving cutter based on a result measured by the tool measuring device, and placing a tooth space formed in the workpiece and an edge tip of the blade in a position corresponding to each other, and a finish machining controlling section by which workpiece is finish machined.

A numerical control apparatus includes: a drive unit controlling a main shaft rotating a workpiece, a first drive shaft feeding a cutting tool relatively to the workpiece along a perpendicular direction to a lead direction of a thread, and a second drive shaft feeding the cutting tool relatively to the workpiece along the lead direction; and a vibration unit superimposing, on movement of the first drive shaft, vibration having a period having a predetermined ratio with a rotation period of the main shaft, and forms a thread on the workpiece by moving the cutting tool and the workpiece relative to each other and performing cut processes on the workpiece. The numerical control apparatus includes a thread-cutting vibration adjustment unit controlling the drive unit to shift phase of the vibration with respect to phase of the main shaft by a predetermined vibration phase shift amount every time in the cut processes.

Method for monitoring a bar blade chucking and/or a blade slot of a bar blade cutter head for bevel gear production, having the following method steps: providing a main body (26) of a bar blade cutter head (4), wherein the main body (26) comprises blade slots (30) for accommodating bar blades (10), and wherein a component (10), such as a bar blade (10), a test specimen, or the like, is chucked in a detachable and replaceable manner in at least one blade slot (30) of the main body (26) of the bar blade cutter head (4); exciting oscillations of the component (10); measuring the displacement and/or velocity and/or acceleration of the component (10); analyzing the measurement.

Provided is a controller for controlling a gear cutting machine having a plurality of axes, the controller including an axis information storage unit configured to store data related to control of the plurality of axes during machining, and a disturbance component identification unit configured to identify a component of disturbance with respect to the plurality of axes using the data stored by the axis information storage unit and measurement results of machining accuracy of a workpiece machined by the cutting machine.

A method of producing a workpiece having a desired gear geometry by means of a suitably dressed tool may include specifying a desired gear geometry of the workpiece and selecting a combination of a dresser and a tool, such that the desired gear geometry of the workpiece can be produced by the selected combination at least within one permitted tolerance. The method may further include dressing the tool with the dresser in line contact for producing a suitable gear geometry of the tool and machining the workpiece with the dressed tool for producing the desired gear geometry of the workpiece at least within a permitted tolerance.

A machine forms threads on a workpiece by relatively feeding the workpiece and a cutting tool in a feeding direction while relatively rotating the workpiece and the cutting tool, and by performing a helical cutting work multiple times while carrying out relative reciprocal vibration of the workpiece and the cutting tool in a radial direction of the workpiece. The machine tool or a control device of the machine tool includes a vibration setting unit to set a pattern of vibration during each cutting work accompanied by the reciprocal vibration so that a cut portion of one cutting work partially includes a portion that has been cut in another cutting work. The machine tool and the control device prevent a long, continuous chip from becoming entangled with a workpiece or a cutting tool in the process of forming threads on the workpiece.

In a method of producing a toothed workpiece having a modified surface geometry by a diagonal generating method by means of a modified tool, a tool may be used whose surface geometry comprises a modification which can be described at least approximately in the generating pattern at least locally in a first direction of the tool by a linear and/or quadratic function, with the specific modification of the tool producing a corresponding modification on the surface of the workpiece by the diagonal generating method, with the modification of the workpiece produced by the specific modification of the tool having a profile modification and/or a modification caused by a change of the machine kinematics during the machining process of the workpiece superposed on it.