A numerical controller includes: a vibration amplitude specifying unit for specifying an amplitude of a vibration component generated by a blade of a tool being brought into contact with a workpiece at a predetermined cycle, due to rotation of a spindle out of a spindle load; a gain calculating unit for calculating a gain of PID control such that an output of the feed speed is uninfluenced by the amplitude, based on the amplitude of the vibration component specified by the vibration amplitude specifying unit; and a speed control unit for outputting a feed speed of the spindle controlled by the PID control, by using the gain calculated by the gain calculating unit.

A rotation controller controls a rotation mechanism for rotation of a spindle. A movement controller causes, while the spindle is rotating, a feed mechanism to bring a cutting tool into contact with a workpiece to cause the cutting tool to cut the workpiece. The rotation controller controls a spindle rotation speed so as to accelerate or decelerate the rotation of the spindle, and the movement controller brings the cutting tool into contact with the workpiece after the rotation controller starts the rotation of the spindle, and separates the cutting tool from the workpiece while the spindle rotation speed is put under the acceleration control or deceleration control exercised by the rotation controller.

To provide a numerical controller for a machine tool capable of reducing heat generation and realizing stable heavy cutting, and also capable of realizing efficient light cutting. A numerical controller comprises: first speed change means which changes the feed speed of a feed axis drive motor at the start of cutting to an initial speed lower than a command speed, based on magnetic flux content at the start of cutting; and second speed change means which changes the feed speed from the initial speed to the command speed continuously or intermittently based on time elapsed from the start of cutting and a time constant for change in the magnetic flux content.

This numeral control device includes a control information storage unit that stores a plurality of control information items for controlling a control shaft of a machine tool; a control information determination unit that, on the basis of a speed command for designating a feed speed of the control shaft or a movement command derived from the speed command, determines one control information item among the plurality of control information items stored in a control information storage unit; and a control unit that controls the control shaft on the basis of the one control information item determined by the control information determination unit.

Provided is a carbon fiber reinforced plastic machining method using a monitoring sensor which includes the step (S10) of electrically connecting a spindle and the monitoring sensor by a computer numerical control (CNC) device, the step (S20) of determining a start position in relation to machining of the spindle and a machining finish position, and the step (S30) of controlling the movement speed and rotation speed of the spindle in accordance with the determination result.

A remote machining optimization system for a machine tool is provided, which includes an input unit configured to input a machining parameter including a spindle speed and a cut depth; a receiving unit configured to receive sound signals and vibration signals from the machine tool; a processing unit configured to generate a machining program with a program generating module, to modify the spindle speed and the cut depth according to the sound signals with a speed optimization module and a depth optimization module, respectively; a communication unit configured to send the machining program to the machine tool; and a storage unit configured to store the modified spindle speed and the cut depth.

A spindle speed adjusting device in machining is provided, which may include a plurality of signal detection modules, a signal capturing module and a signal processing module. Each of the signal detection modules may keep measuring the vibration signals in machining. The signal capturing module may capture the vibration signals. The signal processing module may execute a transmissibility analysis to obtain the transmissibility between the signal detection modules, and execute a frequency response fitting according to the transmissibility to obtain a plurality of system dynamic parameters, and then execute a stability lobe diagram analysis to calculate the optimized spindle speed of the machining tool so as to make the machining tool operate at the optimized spindle speed. The signal processing module may repeatedly execute the transmissibility analysis, the frequency response fitting and the stability lobe diagram analysis to keep updating the optimized spindle speed until the machining process ends.

An estimated force applied by a milling tool at a surface point of a component is determined during milling operations of the component. An estimated deflection of the component associated with the estimated force is determined using the estimated force and a compliance tensor of the component corresponding to the surface point of the component. The estimated deflection of the component is compared to one or more deflection criteria. A feed rate of the milling tool is adjusted during the milling operations of the component based on results of the comparing.

A machine tool includes a spindle retaining a tool, a spindle motor, a feed device relatively moving a workpiece and a tool with a feed motor, a spindle motor control unit, and a feed motor control unit. In a method of machining a workpiece with the machine tool, the spindle motor control unit continuously varies a rotational speed of the spindle in a periodic or non-periodic manner with a predetermined amplitude with respect to a target rotational speed. The feed motor control unit continuously varies a relative moving speed between the tool and the workpiece in synchronization with the spindle motor such that a ratio of the rotational speed of the spindle to the moving speed does not become constant at least in a predetermined time zone in which a spindle speed reaches a maximal value and a predetermined time zone in which the spindle speed reaches a minimal value.

A controller controls a machine tool that rotates a cutting tool attached to a spindle to cut a workpiece in accordance with a machining program. The controller identifies, when the machining program is executed to cause the cutting tool to cut into the workpiece, a position where the cutting tool has come into contact with the workpiece for the first time and a machining direction at the time when the cutting tool has cut into the workpiece, and inserts, in the machining program, a roll-in path instruction having an end point set to the identified position at which the cutting tool has come into contact with the workpiece for the first time.