Abstract: A stick motion correction method which corrects stick motion which occurs at time of reversal of a feed axis of a numerical control machine tool stores a position command to be commanded to a servo motor from an NC program of a numerical control machine tool for each predetermined control period from a current position command to a later position command, calculates a reversal correction command based on the stored position commands, calculates an advancement time for advancing timing of addition of the reversal correction command to a speed or torque command of the motor from reversal timing of the servo motor, based on information obtained from operation of the motor and adds the reversal correction command to the speed or torque command of the servo motor to precisely correct stick motion at a timing advanced from the reversal timing of the servo motor by an exact time.

Abstract: A numerical control device which controls a feed axis of a machine tool has a storage unit which divides a range of movement of the feed axis into a plurality of regions and stores a plurality of control parameters corresponding to the divided plurality of regions in advance, a position detection unit which detects a position of a feed axis at the time of machining a workpiece, a parameter selection unit which reads out control parameters corresponding to a divided region to which the detected feed axis position at the time of machining a workpiece belongs, and a servo control unit which controls the feed axis using the read control parameters. Due to this, it is possible to provide a numerical control method of a machine tool which realizes stable machining precision without regard as to the feed axis position and a numerical control device which conducts that method.

Abstract: In this numerical control method that drives the feed shaft of a machine tool (10) by means of a servo control unit (52), a transmission function is determined by modeling the operation of the servo control unit (52) of the feed shaft, the closed loop transmission function (GBP) of the position loop and/or the closed loop transmission function of the velocity loop of the servo control unit (52) of the machine tool is measured using the frequency response of the feed shaft, the control subject (PP) of the position loop and/or the control subject of the velocity loop is determined using the measured closed loop transmission function, the position loop modeling error (?PP) and/or the velocity loop modeling error is determined from the control subject, and at least one control parameter of the servo control unit (52) is calculated using the closed loop transmission function and/or the modeling error.

Abstract: A stick motion correction method which corrects stick motion which occurs at time of reversal of a feed axis of a numerical control machine tool stores a position command to be commanded to a servo motor from an NC program of a numerical control machine tool for each predetermined control period from a current position command to a later position command, calculates a reversal correction command based on the stored position commands, calculates an advancement time for advancing timing of addition of the reversal correction command to a speed or torque command of the motor from reversal timing of the servo motor, based on information obtained from operation of the motor and adds the reversal correction command to the speed or torque command of the servo motor to precisely correct stick motion at a timing advanced from the reversal timing of the servo motor by an exact time.

Abstract: A numerical control device which controls a feed axis of a machine tool (10) has a storage unit (92) which divides a range of movement of the feed axis into a plurality of regions and stores a plurality of control parameters corresponding to said divided plurality of regions in advance, a position detection unit which detects a position of a feed axis at the time of machining a workpiece, a parameter selection unit (90) which reads out control parameters corresponding to a divided region to which the detected feed axis position at the time of machining a workpiece belongs, and a servo control unit (52) which controls the feed axis using said read control parameters. Due to this, it is possible to provide a numerical control method of a machine tool which realizes stable machining precision without regard as to the feed axis position and a numerical control device which conducts that method.

Abstract: In this numerical control method that drives the feed shaft of a machine tool (10) by means of a servo control unit (52), a transmission function is determined by modeling the operation of the servo control unit (52) of the feed shaft, the closed loop transmission function (GBP) of the position loop and/or the closed loop transmission function of the velocity loop of the servo control unit (52) of the machine tool is measured using the frequency response of the feed shaft, the control subject (PP) of the position loop and/or the control subject of the velocity loop is determined using the measured closed loop transmission function, the position loop modeling error (?PP) and/or the velocity loop modeling error is determined from the control subject, and at least one control parameter of the servo control unit (52) is calculated using the closed loop transmission function and/or the modeling error.

Abstract: A wear amount of a working tool T during the machining of a workpiece is estimated during the machining, and a positional command generated in accordance with a predetermined machining program is sequentially corrected during the machining based on the estimated wear amount of the working tool T. The workpiece W is machined in accordance with the corrected positional command. Also, the wear amount of the working tool T upon the interruption of the machining operation is calculated, and the positional command generated in accordance with the predetermined machining program is corrected based on the calculated wear amount of the working tool so that a tool edge position of the working tool T upon the interruption of the machining operation coincides with the tool edge position of the working tool T upon the restart of the machining operation when the machining operation is restarted at a position where the machining operation has been interrupted.

Abstract: A wear amount of a working tool T during the machining of a workpiece is estimated during the machining, and a positional command generated in accordance with a predetermined machining program is sequentially corrected during the machining based on the estimated wear amount of the working tool T. The workpiece W is machined in accordance with the corrected positional command. Also, the wear amount of the working tool T upon the interruption of the machining operation is calculated, and the positional command generated in accordance with the predetermined machining program is corrected based on the calculated wear amount of the working tool so that a tool edge position of the working tool T upon the interruption of the machining operation coincides with the tool edge position of the working tool T upon the restart of the machining operation when the machining operation is restarted at a position where the machining operation has been interrupted.

Abstract: A control device of a machine tool (100) has an input unit (1) for inputting the processing profile data (1a) and the workpiece data (1b) of the material and a profile of the workpiece to be processed. The control device input unit (1) also can receive a tool path changing operation command (1c), a manual operation command (1d) and a processing condition changing command. A data base (3) for storing at least one of the mechanical data of the machine tool to process the workpiece and the tool data of the tool mounted on the machine tool provides a signal to an estimating calculation unit (7) for estimating at least a processing load or the occurrence of interference of the tool with the workpiece based on the data inputted by the input unit (1) and the data stored in the data base (3).

Abstract: A control apparatus 100 for a machine tool comprises input means 1 for inputting machining profile data 1a on the final profile of a work and workpiece data 1b on the material and profile of the workpiece to be machined, data storage means 3 for storing at least one of machine data representing machine specifications of the machine tool 11 for machining the work and tool data representing the specifications of the tools held in the machine tool, and tool path determining means 5 for generating a tool path for machining the work and determining the conditions for machining the work including the rotational speed of the main spindle and the feed rate of the machine tool 11 based on the data input from said input means and the data stored in said data storage means.

Abstract: The tolerable maximum feed rate Fd is calculated in real time during operation based on the tolerable minimum moving time Ta to be determined by the data interpretation and the moving distance L of each machining block. If the command feed rate Fc exceeds the tolerable maximum feed rate Fd, the actual feed rate for the block is set to the tolerable maximum feed rate Fd, thereby realizing smooth deceleration and preventing mechanical shock of the machine tool and reduction in machining accuracy. Required time for each processing element is determined in advance, the sum of processing times corresponding each element is calculated by judging the processing mode element contained in machining for each block. Then, the feed rate is controlled by determining the tolerable minimum moving time for each block based on the calculated sum of processing times.

Abstract: A tolerable feed rate is calculated to cause mechanical shock not exceeding a tolerable level in an arcuate machining based on the radius of the path of tool movement at arcuate machining portions and the predetermined tolerable acceleration. A deceleration start timing is set by reference to the end of an arcuate machining and the predetermined deceleration so that the feed rate is lower enough to maintain the tolerable mechanical shock at the end of an arcuate machining. An optimum feed rate is set for arcuate and completely circular machining based on the classification judgment of the arc or complete circle.