A method for operating a power tool, wherein the power tool is initially operated with a first combination of operating parameters such that a first working progress is obtained. During operation of the power tool with the first combination of operating parameters, the first working progress can be determined and compared with a second working progress that is obtained when the power tool is operated with a second combination of operating parameters. Depending on the result of the comparison, the power tool can continue to be operated with the second combination of operating parameters or the power tool can return to operation with the first combination of operating parameters. This comparison of the working progresses can be repeated until a maximum, i.e. optimal working progress is reached or found. A power tool, wherein the power tool is preferably in the form of a drill, preferably a core drill.

Provided is a technique that enables appropriate speed adjustment in a speed-adjusted section and inhibition of burring and tool damage without unduly extending cycle time. A speed adjustment device according to the present invention is provided with: a storage unit that stores a calculation method for an adjusted speed of a driving axis in a speed-adjusted section, the adjusted speed being determined in accordance with a tool being used, the shape of a workpiece in the speed-adjusted section, and path information; a speed-adjusted section identification unit that identifies the speed-adjusted section and the shape of the workpiece in the speed-adjusted section on the basis of shape data of the workpiece and the path information; and an adjusted speed calculation unit that determines the calculation method for the adjusted speed of the driving axis in the speed-adjusted section on the basis of tool data, the shape of the workpiece in the identified speed-adjusted section, the path information, and stored information that is stored in the storage unit, and calculates the adjusted speed in the speed-adjusted section on the basis of the determined calculation method.

Provided is a technique that enables appropriate speed adjustment in a speed-adjusted section and inhibition of burring and tool damage without unduly extending cycle time. A speed adjustment device according to the present invention is provided with: a storage unit that stores a calculation method for an adjusted speed of a driving axis in a speed-adjusted section, the adjusted speed being determined in accordance with a tool being used, the shape of a workpiece in the speed-adjusted section, and path information; a speed-adjusted section identification unit that identifies the speed-adjusted section and the shape of the workpiece in the speed-adjusted section on the basis of shape data of the workpiece and the path information; and an adjusted speed calculation unit that determines the calculation method for the adjusted speed of the driving axis in the speed-adjusted section on the basis of tool data, the shape of the workpiece in the identified speed-adjusted section, the path information, and stored information that is stored in the storage unit, and calculates the adjusted speed in the speed-adjusted section on the basis of the determined calculation method.

Provided is a machine tool control device that can realize a desired scrap length while suppressing deterioration in machining accuracy. This control device 1 is for a machine tool which performs machining while causing a tool and a workpiece to oscillate relative to each other, the control device 1 being provided with: an oscillation command generation unit 13 for generating an oscillation command on the basis of an oscillation condition; an oscillation command correction unit 14 for correcting the oscillation command so that main-axis phases in given oscillation phases are not identical to each other; and a position/speed control unit 18 for causing the tool and the workpiece to oscillate relative to each other on the basis of a superposition command generated by superposing the oscillation command corrected by the oscillation command correction unit 14 on a movement command.

Provided is a machine tool control device that can realize a desired scrap length while suppressing deterioration in machining accuracy. This control device 1 is for a machine tool which performs machining while causing a tool and a workpiece to oscillate relative to each other, the control device 1 being provided with: an oscillation command generation unit 13 for generating an oscillation command on the basis of an oscillation condition; an oscillation command correction unit 14 for correcting the oscillation command so that main-axis phases in given oscillation phases are not identical to each other; and a position/speed control unit 18 for causing the tool and the workpiece to oscillate relative to each other on the basis of a superposition command generated by superposing the oscillation command corrected by the oscillation command correction unit 14 on a movement command.

Oscillation for a direct distance between the centers of a tool T and a workpiece W to meet l+al(1cos(Mt)) and vertical oscillation to meet alsin(Mt) are applied alone or in combination with time t, where denotes an angular velocity of a workpiece, M denotes the number of sides of a polygon, and a denotes an adjustment parameter. Such oscillation enables adjustment as to how the machining surface is made concave or convex.

Oscillation for a direct distance between the centers of a tool T and a workpiece W to meet l+al(1cos(Mt)) and vertical oscillation to meet alsin(Mt) are applied alone or in combination with time t, where denotes an angular velocity of a workpiece, M denotes the number of sides of a polygon, and a denotes an adjustment parameter. Such oscillation enables adjustment as to how the machining surface is made concave or convex.