A cutting apparatus having a cutting blade for cutting a workpiece held on a chuck table is disclosed. The cutting apparatus includes an elastic wave detecting sensor for detecting an elastic wave due to the rotation of the cutting blade, a reference data storing section configured to store reference data as a set of reference processing elastic wave data and reference idling elastic wave data, a threshold value storing section, a ratio calculating section, and a determining section.

A cutting apparatus having a cutting blade for cutting a workpiece held on a chuck table is disclosed. The cutting apparatus includes an elastic wave detecting sensor for detecting an elastic wave due to the rotation of the cutting blade, a reference data storing section configured to store reference data as a set of reference processing elastic wave data and reference idling elastic wave data, a threshold value storing section, a ratio calculating section, and a determining section.

A numerical control device is for machining a machining object by moving a tool and the machining object relative to each other along a movement path while applying vibration, by use of a drive axis provided for the tool or the machining object. The device includes a storage unit that holds an invalid frequency region, and a vibration condition determining unit to determine a frequency for the vibration, based on a rotational speed of a main shaft for rotating the machining object, a number of vibrations of the vibration in each one rotation of the main shaft, and the invalid frequency region.

A numerical control device is for machining a machining object by moving a tool and the machining object relative to each other along a movement path while applying vibration, by use of a drive axis provided for the tool or the machining object. The device includes a storage unit that holds an invalid frequency region, and a vibration condition determining unit to determine a frequency for the vibration, based on a rotational speed of a main shaft for rotating the machining object, a number of vibrations of the vibration in each one rotation of the main shaft, and the invalid frequency region.

A machine tool includes an input interface configured to receive an instruction, an actuator configured to actuate, control circuitry configured to control an actuation of the actuator based on the instruction, a component having a physical state to be affected by the actuation, a sensor configured to detect the physical state, and a computer connected to the control circuitry via an external communication interface. The computer is configured to receive a signal from the sensor, generate, based on the signal, rough state-description data relevant to an occurrence of an abnormality in the component, transmit the rough state-description data to the control circuitry, generate detailed state-description data based on the signal, the detailed state-description data being more informative than the rough state-description data such that the detailed state-description data facilitates identifying an abnormal part in the component, and transmit the detailed state-description data to a monitoring computer via a communication network.

A machine tool includes an input interface configured to receive an instruction, an actuator configured to actuate, control circuitry configured to control an actuation of the actuator based on the instruction, a component having a physical state to be affected by the actuation, a sensor configured to detect the physical state, and a computer connected to the control circuitry via an external communication interface. The computer is configured to receive a signal from the sensor, generate, based on the signal, rough state-description data relevant to an occurrence of an abnormality in the component, transmit the rough state-description data to the control circuitry, generate detailed state-description data based on the signal, the detailed state-description data being more informative than the rough state-description data such that the detailed state-description data facilitates identifying an abnormal part in the component, and transmit the detailed state-description data to a monitoring computer via a communication network.

A machine tool includes: a first calculator configured to calculate a first frequency characteristic based on a first oscillation signal and a measurement signal of a physical quantity measured by a measurement unit when the drive shaft of a servo motor swings in accordance with the first oscillation signal; and a second calculator configured to calculate a second frequency characteristic based on a second oscillation signal and a measurement signal of the physical quantity measured by the measurement unit when the drive shaft of the servo motor swings in accordance with the second oscillation signal.

A machine tool includes: a first calculator configured to calculate a first frequency characteristic based on a first oscillation signal and a measurement signal of a physical quantity measured by a measurement unit when the drive shaft of a servo motor swings in accordance with the first oscillation signal; and a second calculator configured to calculate a second frequency characteristic based on a second oscillation signal and a measurement signal of the physical quantity measured by the measurement unit when the drive shaft of the servo motor swings in accordance with the second oscillation signal.

A tool attachment abnormality detection device acquires data associated with a machining center, performs pre-processing to create data regarding at least chronological data of a vibration or sound that has been generated in a tool change when a tool has been attached to a tool magazine, where the data is created based on the data that has been acquired, and detects an abnormality in attachment of the tool to the tool magazine based on the data created in the pre-processing stage.

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.