Methods of machining a body to produce a chip are provided wherein the body is formed of a material and in a state such that the material exhibits sinuous flow during a machining operation. The methods include providing a layer located on a surface of the body, and machining the body by causing engagement between a cutting tool and the body in a contact region below an area of the surface having the coating layer thereon and moving the cutting tool relative to the body to produce the chip having the layer thereon. The layer reduces sinuous flow in the material of the body and the chip is formed primarily by laminar flow.

Methods of machining a body to produce a chip are provided wherein the body is formed of a material and in a state such that the material exhibits sinuous flow during a machining operation. The methods include providing a layer located on a surface of the body, and machining the body by causing engagement between a cutting tool and the body in a contact region below an area of the surface having the coating layer thereon and moving the cutting tool relative to the body to produce the chip having the layer thereon. The layer reduces sinuous flow in the material of the body and the chip is formed primarily by laminar flow.

A machining device threads a workpiece by relatively rotating the workpiece and a multi-blade tool and relatively moving them along a feed direction to perform cutting processes in the radial direction of the workpiece along the same cutting path in a predetermined spiral form. A controller performs a groove machining to form a threaded portion with vibration in the radial direction of the workpiece and a finish machining to form the threaded portion by bringing the multi-blade tool into contact with the grooved portion of the workpiece. The multi-blade tool has a first cutting blade and a second cutting blade arranged side by side along the feed direction. The controller sets amplitude of a vibration waveform to a value at which a cutting edge of the second cutting blade does not come into contact with the screw bottom surface of the workpiece in the finish machining.

A machining device threads a workpiece by relatively rotating the workpiece and a multi-blade tool and relatively moving them along a feed direction to perform cutting processes in the radial direction of the workpiece along the same cutting path in a predetermined spiral form. A controller performs a groove machining to form a threaded portion with vibration in the radial direction of the workpiece and a finish machining to form the threaded portion by bringing the multi-blade tool into contact with the grooved portion of the workpiece. The multi-blade tool has a first cutting blade and a second cutting blade arranged side by side along the feed direction. The controller sets amplitude of a vibration waveform to a value at which a cutting edge of the second cutting blade does not come into contact with the screw bottom surface of the workpiece in the finish machining.

Provided is a machine tool control device capable of promptly determining a frequency parameter and an amplitude parameter for a desired oscillation instruction enabling shredding of a chip. A machine tool control device 1 performs machining while causing a tool T and a workpiece W to oscillate relative to each other. The machine tool control device 1 is provided with an oscillation instruction calculation unit 113 that calculates an instruction for an oscillating operation; a first oscillation condition determination unit 111 that determines, as a first oscillation condition, one of a frequency parameter constituted of a frequency or a frequency multiplying factor of the oscillation instruction, and an amplitude parameter constituted of an amplitude or an amplitude multiplying factor of the oscillation instruction; and a second oscillation condition calculation unit 112 that calculates, as a second oscillation condition, the other of the frequency parameter and the amplitude parameter on the basis of the first oscillation condition determined by the first oscillation condition determination unit 111.

Provided is a machine tool control device capable of promptly determining a frequency parameter and an amplitude parameter for a desired oscillation instruction enabling shredding of a chip. A machine tool control device 1 performs machining while causing a tool T and a workpiece W to oscillate relative to each other. The machine tool control device 1 is provided with an oscillation instruction calculation unit 113 that calculates an instruction for an oscillating operation; a first oscillation condition determination unit 111 that determines, as a first oscillation condition, one of a frequency parameter constituted of a frequency or a frequency multiplying factor of the oscillation instruction, and an amplitude parameter constituted of an amplitude or an amplitude multiplying factor of the oscillation instruction; and a second oscillation condition calculation unit 112 that calculates, as a second oscillation condition, the other of the frequency parameter and the amplitude parameter on the basis of the first oscillation condition determined by the first oscillation condition determination unit 111.

The purpose of the present invention is to both break down chips and suppress sympathetic vibration in a machine. This work machine control device superposes a swinging command for commanding relative swinging between a workpiece and a cutting tool onto a movement command for commanding relative movement between the workpiece and the cutting tool, thereby generating air cuts in chips from the workpiece to break down the chips. A position information acquisition unit of the work machine control device acquires position information related to the relative positions of the workpiece and the tool. A state assessment unit of the work machine control device assesses that a state of instability is in effect, under the condition that a positional deviation exceeds a threshold value, the positional deviation increasing with increases in the difference between actual relative positions that are based on the position information and command relative positions that are based on the movement command and the swinging command. A swinging switching unit of the work machine control device performs a switching process for switching a swinging condition in relative swinging, under the condition that it is assessed that the state of instability is in effect.

The purpose of the present invention is to both break down chips and suppress sympathetic vibration in a machine. This work machine control device superposes a swinging command for commanding relative swinging between a workpiece and a cutting tool onto a movement command for commanding relative movement between the workpiece and the cutting tool, thereby generating air cuts in chips from the workpiece to break down the chips. A position information acquisition unit of the work machine control device acquires position information related to the relative positions of the workpiece and the tool. A state assessment unit of the work machine control device assesses that a state of instability is in effect, under the condition that a positional deviation exceeds a threshold value, the positional deviation increasing with increases in the difference between actual relative positions that are based on the position information and command relative positions that are based on the movement command and the swinging command. A swinging switching unit of the work machine control device performs a switching process for switching a swinging condition in relative swinging, under the condition that it is assessed that the state of instability is in effect.

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.