An industrial process field device includes an active component, a switch, a switch monitor, and a controller. The active component may be a sensor configured to sense a process parameter, or a control device configured to control a process of the industrial process. The switch is electrically coupled to first and second terminals. The switch monitor is configured to detect an open or closed state of the switch, and generate a first state output, a second state output, or a chattering state output. An anti-chatter circuit outputs a chatter stabilized state output based on the chattering state output. The controller is configured to set the switch in the open or closed state, and generate a notification based on any one of the first and second state outputs and the chatter stabilized state output that indicates at least one of the current state and a condition of the switch.

A machine tool is configured to machine a workpiece by rotating a tool and/or the workpiece. The machine tool includes a natural frequency changing unit configured to change a natural frequency before machining or during machining in the tool or a supporting portion supporting the tool.

An apparatus includes vibration data obtainer 30 obtaining data on vibration caused by a tool in cutting, a vibration frequency calculator 22 calculating a vibration frequency of the tool by analyzing the obtained vibration data, a regenerative chatter detector 23 detecting whether regenerative chatter occurs by comparing the calculated vibration frequency of the tool with a spindle rotation number, and a spindle rotation controller 24 gradually decreasing or increasing the spindle rotation number when occurrence of regenerative chatter vibration is detected, and a stable rotation number calculator 25 monitoring variation of the vibration frequency of the tool and determining a spindle rotation number when the variation of the vibration frequency exceeds a predetermined reference value to be a stable rotation number.

A control device of a machine tool receives a target machining, in accordance with which a workpiece should be machined by a tool of the machine too!. The control device also receives via a human-machine interface or via an interface to an external memory device a selection, a parameterization and/or a specification of a sequence of predefined rules, which define the manner in which the machining of the workpiece should be modified in the event of undesired vibrations during machining. When undesired vibrations do not occur, as determined from acquired sensor signals, machining is carried out in accordance with the target machining. When undesired vibrations occur, the machining is modified in accordance with the rules, wherein the control device selects the rules in accordance with the selection, parameterizes the rules in accordance with the parameterization and/or carries out the rules in accordance with the specified sequence. ma

A chatter vibration determination device is provided with a machine learning device configured to observe machining condition data including a feed speed and a spindle rotational frequency in cutting as state data representative of the current state of environment, execute processing related to machine learning using a learning model obtained by modeling the relationship of chatter vibration with a machining condition for the cutting, based on the state data, and estimate the occurrence/non-occurrence of chatter vibration and the improvement of the chatter vibration. The chatter vibration determination device outputs the result of the estimation of the occurrence/non-occurrence of the chatter vibration and the improvement of the chatter vibration.

A control device of a machine tool receives a target machining, in accordance with which a workpiece should be machined by a tool of the machine tool. The control device also receives via a human-machine interface or via an interface to an external memory device a selection, a parameterization and/or a specification of a sequence of predefined rules, which define the manner in which the machining of the workpiece should be modified in the event of undesired vibrations during machining. When undesired vibrations do not occur, as determined from acquired sensor signals, machining is carried out in accordance with the target machining. When undesired vibrations occur, the machining is modified in accordance with the rules, wherein the control device selects the rules in accordance with the selection, parameterizes the rules in accordance with the parameterization and/or carries out the rules in accordance with the specified sequence.

A numerical control device according to an embodiment of the present disclosure is a numerical control device for controlling at least two oscillating drive axes which linearly drive so as to cause mutually differing targets to change speed regularly at a fixed period, based on a machining program, in which the numerical control device controls the at least two oscillating drive axes so as to keep fixed a phase difference of periodic variable components of the at least two oscillating drive axes.

A numerical control device according to an embodiment of the present disclosure is a numerical control device for controlling at least two oscillating drive axes which linearly drive so as to cause mutually differing targets to change speed regularly at a fixed period, based on a machining program, in which the numerical control device controls the at least two oscillating drive axes so as to keep fixed a phase difference of periodic variable components of the at least two oscillating drive axes.

A chatter vibration determination device is provided with a machine learning device configured to observe machining condition data including a feed speed and a spindle rotational frequency in cutting as state data representative of the current state of environment, execute processing related to machine learning using a learning model obtained by modeling the relationship of chatter vibration with a machining condition for the cutting, based on the state data, and estimate the occurrence/non-occurrence of chatter vibration and the improvement of the chatter vibration. The chatter vibration determination device outputs the result of the estimation of the occurrence/non-occurrence of the chatter vibration and the improvement of the chatter vibration.

A numerical control method at least controls a spindle motor of a machine tool so as to perform machining in accordance with machining conditions. In the method, vibration occurring in a tool is acquired with a vibration acquisition unit, and the machining on a workpiece performed by a machining control unit is stopped when vibration having a predetermined amplitude or greater occurs in the tool. Based on state data indicating the state of the spindle motor at that time, multiple compensation plans for compensating the state of the spindle motor in order to suppress vibration occurring in the tool are calculated. The thus calculated multiple compensation plans are displayed on a display unit together with the state of the spindle motor at the time of occurrence of vibration having the predetermined amplitude or greater in the tool.