Abstract: A servo motor controlling method includes: directly or indirectly detecting a position of a moving body which performs a circular-arc interpolation feeding motion by a servo motor; performing a feedback control for enabling the position of the moving body to comply with a position command; and at a quadrant changing time when a moving direction of the moving body is changed, performing torque correction on a torque command value according to a distance from a position where the moving direction is changed. By this method, a quadrant protrusion and a torque change with respect to a friction caused from a free zone at a time of reversion of a ball screw can be appropriately corrected. Especially, by performing a first torque correction for a static friction at the position where the moving direction is changed, and by performing a second torque correction for a moving friction after movement by the distance corresponding to the free zone, more appropriate correction can be obtained.

Abstract: A servo motor controlling method includes: directly or indirectly detecting a position of a moving body which performs a circular-arc interpolation feeding motion by a servo motor; performing a feedback control for enabling the position of the moving body to comply with a position command; and at a quadrant changing time when a moving direction of the moving body is changed, performing torque correction on a torque command value according to a distance from a position where the moving direction is changed. By this method, a quadrant protrusion and a torque change with respect to a friction caused from a free zone at a time of reversion of a ball screw can be appropriately corrected. Especially, by performing a first torque correction for a static friction at the position where the moving direction is changed, and by performing a second torque correction for a moving friction after movement by the distance corresponding to the free zone, more appropriate correction can be obtained.

Abstract: A numerical control device is disclosed having a parameter memory section 12B that stores discrete optimum parameters for respective operational modes, an operational mode setting switch 20 to allow operational modes to be selectively set through user's operation, and a defect content setting means for registering defect contents of machined results. The optimum parameter, suited for a particular operational mode selected and set with the operational mode setting switch 20, is retrieved for executing setting of the parameter while enabling setting of the parameter based on information obtained with the defect content setting means.

Abstract: A position control apparatus and method has been devised which provides for an improved means of suppressing tracking error from a variable position reference occurring when a control object positioned via a transmission mechanism with mechanical transmission error resumes movement from a state stopped at a target position. A selection between two alternative tracking error compensating means within the control apparatus is made based on whether the detected position of the control object changes in a period after the control object stops and before the variable position reference is input again to a control deviation generating unit.

Abstract: A portion (14a, 14b) of a chip remover (14) is defined to be vibratory to give an NC machine tool (MT 1) a vibration transferable onto a surface (FS) of a work (13) under a finishing by the NC machine tool (MT1), a decision is made whether the NC machine tool (MT1) enters the finishing, and vibration of the vibratory portion (14a, 14b) is controlled, as the decision is true. A chip removal method and an NC machine tool equipped with a spiral chip remover (113) as a chip remover have various chip removal rules for determining permission/prohibition of the operation of the spiral chip remover (113). This spiral chip remover (113) operates based on commands described in a machining program. When a command in the machining program is executed, the permission/prohibition of the operation of the spiral chip remover (113) is controlled according to the chip removal rules.

Abstract: A positional control system wherein the position of the controlled object connected to a drive is controlled to a variable target or desired position. A period is determined which starts with a detection of a reversal in the direction of the feed of a positional command Pr as well as the detection of a stoppage of a table 104 as a controlled object and which ends with a detection of the re-start of the movement of the table 104. During the period, a correction amount for correcting a positional deviation E is issued.

Abstract: A feed velocity of a control axis and acceleration thereof do not exceed a maximum feed velocity and a maximum acceleration defined in mechanical specifications even if a radial operation is carried out for the purpose of a cut-in or escape operation in a contour describing control. A radial permissible maximum velocity (Vnp) and a radial permissible maximum acceleration (&agr;np) in a contour describing control using a circular interpolation is set separately from a setting value of a maximum feed velocity (Vm) of a control axis and that of a maximum acceleration (&agr;m) thereof set as mechanical specifications, and when a command of the circular interpolation is given, limitations are given to a radial velocity (Vn) and acceleration (&agr;n) so that the radial velocity (Vn) and acceleration (&agr;n) do not exceed the radial permissible maximum velocity (Vnp) and permissible maximum acceleration (&agr;np).

Abstract: A lost motion correction value setting method for a machine tool of a hybrid control system that performs a positional loop control with both machine position signals outputted from position detecting scales for detecting machine positions and motor position signals outputted from rotary encoders for detecting a rotational angle of a feed driving servomotor includes executing a test program; periodically inputting the machine position signals outputted from the position detecting scale and the motor position signals outputted from the rotary encoder; determining errors by determining the difference between the machine position signals and the motor position signals, determining the difference between an average value on an advance side and an average value on a return side of the errors, and storing the difference in lost motion correction value memories as a dynamic lost motion correction value.

Abstract: The servo control method operates a set value of a first-order lag time constant of a feedback compensation by both a detected mechanical position value and a transfer function corresponding to a change of an angular velocity about each axis under a multiple-axes simultaneous control. Further, the servo control method sets a feedforward amount so that the transfer function about the each axis is the same.

Abstract: For an orbit boring to be performed by a tool (10) in an orbital motion along an orbit (A), a permissible range of an acceleration (a) of the orbital motion is provided to meet a criterion of a machining precision of the orbit boring, and the acceleration (a) is controlled to be suppressed within the permissible range.

Abstract: A machining program is read in and interpreted and a determination is made as to whether the amount of movement called for by a block of commands is larger or smaller than a minimum amount of movement that is established by a feed speed and a one sampling period of a numerical control apparatus. If the amount of movement called for is greater than the minimum amount of movement, feed control is performed in accordance with the current block. If the amount of movement called for by the current block of commands is smaller than the minimum movement amount, an immediate subsequent block of commands is concatenated with the current block, and this concatenation of command blocks is continued until a synthesized block calling for an amount of movement greater than the minimum amount of movement is obtained, this synthesized block then being used to perform feed control.

Abstract: A numerical control device is disclosed having a parameter memory section 12B that stores discrete optimum parameters for respective operational modes, an operational mode setting switch 20 to allow operational modes to be selectively set through user's operation, and a defect content setting means for registering defect contents of machined results. The optimum parameter, suited for a particular operational mode selected and set with the operational mode setting switch 20, is retrieved for executing setting of the parameter while enabling setting of the parameter based on information obtained with the defect content setting means.

Abstract: A portion (14a, 14b) of a chip remover (14) is defined to be vibratory to give an NC machine tool (MT1) a vibration transferable onto a surface (FS) of a work (13) under a finishing by the NC machine tool (MT1), a decision is made whether the NC machine tool (MT1) enters the finishing, and vibration of the vibratory portion (14a, 14b) is controlled, as the decision is true.

Abstract: The servo control method operates a set value of a first-order lag time constant of a feedback compensation by both a detected mechanical position value and a transfer function corresponding to a change of an angular velocity about each axis under a multiple-axes simultaneous control. Further, the servo control method sets a feedforward amount so that the transfer function about the each axis is the same.

Abstract: For an orbit boring to be performed by a tool (10) in an orbital motion along an orbit (A), a permissible range of an acceleration (a) of the orbital motion is provided to meet a criterion of a machining precision of the orbit boring, and the acceleration (a) is controlled to be suppressed within the permissible range.

Abstract: A feed velocity of a control axis and acceleration thereof do not exceed a maximum feed velocity and a maximum acceleration defined in mechanical specifications even if a radial operation is carried out for the purpose of a cut-in or escape operation in a contour describing control A radial permissible maximum velocity (Vnp) and a radial permissible maximum acceleration (&agr;np) in a contour describing control using a circular interpolation is set separately from a setting value of a maximum feed velocity (Vm) of a control axis and that of a maximum acceleration (&agr;m) thereof set as mechanical specifications, and when a command of the circular interpolation is given, limitations are given to a radial velocity (Vn) and acceleration (&agr;n) so that the radial velocity (Vn) and acceleration (&agr;n) do not exceed the radial permissible maximum velocity (Vnp) and permissible maximum acceleration (&agr;np).

Abstract: A position control apparatus for positioning a control object connected with a motor via a transmission mechanism so as to track a variable position reference varying with time, having a reference generating unit for generating the variable position reference; a control deviation generating unit for generating control deviation of the control object based on the variable position reference and a detected position of the control object or these and a detected rotational position of the motor; a servo control unit for generating a control quantity to make the control object track the variable position reference based on the control deviation and controlling the driving of the motor; a tracking error compensating unit having a first and second compensating unit of different modes for compensating for the control deviation or for correcting the detected rotational position of the motor used for generation of the control deviation so as to suppress tracking error of the control object from the variable position re

Abstract: The invention relates to a numerical controlling unit 10 having a speed-feedback controlling system. A peak-frequency detector 20 determines a peak frequency from a characteristic of a frequency transfer function whose input is a speed-instruction input signal and whose output is a speed feedback signal. A band elimination component 30 conducts a band elimination process to the speed-instruction input signal, based on the peak frequency.

Abstract: A positional control system wherein the position of the controlled object connected to a drive means is controlled to a variable target or desired position. A period is determined which starts with a detection of a reversal in the direction of the feed of a positional command Pr as well as the detection of a stoppage of a table 104 as a controlled object and which ends with a detection of the re-start of the movement of the table 104. During the period, a correction amount for correcting a positional deviation E is issued.

Abstract: A lost motion correction value setting method for a machine tool of a hybrid control system that performs a positional loop control with both machine position signals outputted from position detecting scales (9x and 9y) for detecting machine positions and motor position signals outputted from rotary encoders (7x and 7y) for detecting a rotational angle of a feed driving servomotor includes executing a test program; periodically inputting the machine position signals outputted from the position detecting scale and the motor position signals outputted from the rotary encoder; determining errors by determining the difference between the machine position signals and the motor position signals, determining the difference between an average value on an advance side and an average value on a return side of the errors, and storing the difference in lost motion correction value memories (19x and 19y) as a dynamic lost motion correction value.