A method for detecting whether a slip clutch release event has taken place in a power tool includes determining a first speed of a gear device by a first sensor, determining a second speed of a motor by a second sensor, and determining a current value by a third sensor. The method further includes determining a state of the power tool by using the first and second speeds and the current value, determining a state of the gear device in dependence on the current value by a control device, ascertaining a state of activity of the slip clutch in dependence on the first and second speeds by the control device, and ascertaining by the control device by a combination of the state of the gear device and the state of activity of the slip clutch whether the slip clutch release event has taken place.

A main spindle failure detection device for a machine tool includes a rotation speed detection unit, a reach time estimation unit, and a determining unit. The reach time estimation unit is configured to estimate a reach time in which the rotation speed of the main spindle reaches a predetermined rotation speed threshold using a non-linear model based on a rotation speed of the main spindle detected at a start of an inertia operation and a rotation speed of the main spindle detected after an elapse of preset measurement time from the start of the inertia operation. The determining unit is configured to compare the reach time estimated by the reach time estimation unit with a preset reach time in which the rotation speed reaches the rotation speed threshold, so as to determine a failure in the main spindle based on a result of the comparison.

A main spindle failure detection device for a machine tool includes a rotation speed detection unit, a reach time estimation unit, and a determining unit. The reach time estimation unit is configured to estimate a reach time in which the rotation speed of the main spindle reaches a predetermined rotation speed threshold using a non-linear model based on a rotation speed of the main spindle detected at a start of an inertia operation and a rotation speed of the main spindle detected after an elapse of preset measurement time from the start of the inertia operation. The determining unit is configured to compare the reach time estimated by the reach time estimation unit with a preset reach time in which the rotation speed reaches the rotation speed threshold, so as to determine a failure in the main spindle based on a result of the comparison.

A machine tool is provided capable of detecting an abnormality caused by detaching a spindle. The machine tool includes: the spindle configured to rotate a workpiece or a tool; a sensor configured to output a signal according to a rotation angle of the spindle; and a controller configured to detect occurrence of an abnormality in at least one of the spindle and the sensor when an electrical signal different from the signal output during each of rotation of the spindle and halt of the spindle is output from the sensor.

A power tool including a motor configured to rotatably drive an output shaft, a variable motor speed control input, a motor speed limit input, and a motor controller. The motor controller includes an electronic processor and a memory configured to store instructions. When executed by the motor controller, the instructions configure the motor controller to detect a motor speed limit from a setting of the motor speed limit input, and detect a variable speed control setting from the variable motor speed control input. The motor controller generates a motor speed control signal for driving the motor based on the detected motor speed limit and the detected variable motor speed control setting, and transmits the motor speed control signal to a motor driver circuit configured to drive the motor at a speed based on the motor speed control signal.

A power tool including a motor configured to rotatably drive an output shaft, a variable motor speed control input, a motor speed limit input, and a motor controller. The motor controller includes an electronic processor and a memory configured to store instructions. When executed by the motor controller, the instructions configure the motor controller to detect a motor speed limit from a setting of the motor speed limit input, and detect a variable speed control setting from the variable motor speed control input. The motor controller generates a motor speed control signal for driving the motor based on the detected motor speed limit and the detected variable motor speed control setting, and transmits the motor speed control signal to a motor driver circuit configured to drive the motor at a speed based on the motor speed control signal.

A processing system includes a drilling tool and a chamfering tool that process a workpiece. The workpiece includes a first plate that includes: a first hole penetrating a first front surface and a first back surface; an opening edge constituting the first hole, a front-side first opening edge being provided in the first front surface; a back-side first opening edge constituting the first hole, the back-side first opening edge being provided in the first back surface; and a first chamfered portion provided on at least one of the front-side first opening edge and the back-side first opening edge, and the workpiece includes a second plate that includes: a second hole including a back-side second opening edge provided in at least a second back surface; and a back-side second chamfered portion provided at the back-side second opening edge, an axis of the first hole and an axis of the second hole are coaxial, and the at least one of the first chamfered portion and the back-side second chamfered portion have a cutting mark.

A processing system includes a drilling tool and a chamfering tool that process a workpiece. The workpiece includes a first plate that includes: a first hole penetrating a first front surface and a first back surface; an opening edge constituting the first hole, a front-side first opening edge being provided in the first front surface; a back-side first opening edge constituting the first hole, the back-side first opening edge being provided in the first back surface; and a first chamfered portion provided on at least one of the front-side first opening edge and the back-side first opening edge, and the workpiece includes a second plate that includes: a second hole including a back-side second opening edge provided in at least a second back surface; and a back-side second chamfered portion provided at the back-side second opening edge, an axis of the first hole and an axis of the second hole are coaxial, and the at least one of the first chamfered portion and the back-side second chamfered portion have a cutting mark.

To provide a machine tool and a control device for the machine tool that can smoothly cut a workpiece while segmenting chips by feeding a cutting tool in a feed direction while reciprocally vibrating the cutting tool along the feed direction on the basis of a condition set by a user. The machine tool (100) or the control device (C) includes the control section (C1) that determines a number of rotations of the relative rotation and a number of vibrations of the reciprocal vibration per rotation of the relative rotation when the workpiece (W) is machined in accordance with a vibration frequency dependent on a period in which an operating instruction can be executed.

A main spindle failure detection device for a machine tool includes a rotation speed detection unit, a reach time estimation unit, and a determining unit. The reach time estimation unit is configured to estimate a reach time in which the rotation speed of the main spindle reaches a predetermined rotation speed threshold using a non-linear model based on a rotation speed of the main spindle detected at a start of an inertia operation and a rotation speed of the main spindle detected after an elapse of preset measurement time from the start of the inertia operation. The determining unit is configured to compare the reach time estimated by the reach time estimation unit with a preset reach time in which the rotation speed reaches the rotation speed threshold, so as to determine a failure in the main spindle based on a result of the comparison.