Abstract: In the processing preparation operation for checking a processing program and the tool compensation amount, a series of confirmation operations for all the tools are easily made using the processing program as conventionally used, without having limitations on the creation of the processing program. When a read skip signal 110 is externally input into a numerical control apparatus, the same instruction as stored in mandatory execution instruction storing means 104 is executed, when commanded in the processing program 100, until the same instruction as stored in read skip end instruction storing means 105 is commanded, but the other instructions are skipped, until the same instruction as stored in read skip end instruction storing means 105 is commanded. Then, when the instruction stored in the read skip end instruction storing means 105 is read, the instruction and subsequent instructions are executed.

Abstract: In the processing preparation operation for checking a processing program and the tool compensation amount, a series of confirmation operations for all the tools are easily made using the processing program as conventionally used, without having limitations on the creation of the processing program. When a read skip signal 110 is externally input into a numerical control apparatus, the same instruction as stored in mandatory execution instruction storing means 104 is executed, when commanded in the processing program 100, until the same instruction as stored in read skip end instruction storing means 105 is commanded, but the other instructions are skipped, until the same instruction as stored in read skip end instruction storing means 105 is commanded. Then, when the instruction stored in the read skip end instruction storing means 105 is read, the instruction and subsequent instructions are executed.

Abstract: The operation of positioning a machine by a numerical control apparatus is completed when it is determined that a current feedback value of a motor, which varies in response to deflection of the machine, is in a given range.

Abstract: A numerical control unit for controlling the position of a movable part, such as a machine table, in response to input machining information. The unit employs a servo control loop that detects the values of the position, velocity, acceleration and motor current for the movable part at predetermined times. Using such detected values and, on the basis of a representative spring mass system model, values of inertia, mass, viscous friction and sliding friction can be calculated and used for automatically optimizing the gain and offset parameters applicable to control of the machine.

Abstract: A device for correcting mechanical errors in an NC machine, by which an incremental amount of movement of a control shaft is corrected for mechanical errors such as backlash and lost motion and the value thus corrected is transmitted to a servo control section. The incremental amount of movement of the control shaft calculated every sampling is subjected to a speed adjustment. A position command value is calculated by progressively adding a command value of the incremental amount of movement subjected to a speed adjustment. A position command correction value is obtained by adding a predetermined amount of correction for mechanical error to the position command value. A corrected incremental amount of movement is calculated by substracting a previously calculated position command correction value, and is transmitted to the servo control section.

Abstract: A numerical control device comprising a lost motion correction data calculating device having a table/function which represents the motor current of a servo motor, in a servo mechanism for servo-controlling a mechanical movable part. The motor current is detected at a given time instant, and the corresponding amount of lost motion correction is then calculated. The position error caused by the lost motion can be corrected with high accuracy.

Abstract: An improvement in a numerical control apparatus for controlling a threading operation with a tap. A numerical control apparatus of the present invention which is simple in construction and needs no dummy mechanism such as a floating tapper; and which minimizes the drift of the tap in the bottom of a tapped hole by an instruction to a feed shaft which switches an acceleration or deceleration time constant, and a simultaneous instruction to a spindle device which controls the position of the spindle device. Thus, the machining precision of the bottom of the tapped hole is improved, and a high-speed tapping operation is possible. Furthermore, the numerical control device also is capable of preventing the tap and the threaded portion machined by the tap from being damaged upon an occurrence of an abnormal condition by an instruction from the removing control unit.