A controller for a wire electric discharge machine recognizes that a consumable, such as a filter, an electrode pin, and an ion exchange resin, has reached the end of its life and the timing at which discharge machining is interrupted and temporarily stops programmed operation in accordance with the timing. When receiving an evaluation result representing that time for exchange of the consumable has been reached, the controller instructs a consumable exchanging unit, such as a robot, to cause it to exchange the consumable for automatic exchange of the consumable. After the consumable has been exchanged, a programmed operation resumption instructing unit resumes the programmed operation.

The numerical controller creates a machining path on which a wire electrode is moved by analyzing blocks of a machining program, and creates interpolation data indicating an amount of movement for each interpolation period on the machining path. Further, the numerical controller calculates a length of the wire electrode used for machining (machined surface length) for each interpolation period, calculates a consumption amount of the wire electrode for each interpolation period, calculates a compensation amount for compensating the amount of movement based on the interpolation data, on the basis of the calculated consumption amount and compensates the amount of movement indicated by the interpolation data, based on the calculated compensation amount.

A controller for a wire electrical discharge machine includes: an abnormality location calculating unit that calculates an abnormality location at a time when an abnormality of the wire electrode has occurred on a wire running path; a solution information storage unit that stores abnormality locations and solution information in association with each other; a priority setting unit that sets a degree of priority for each of the abnormality locations according to a history of the abnormality location; and a display control unit that causes a display unit to display the solution information corresponding to each of the abnormality locations by taking the degree of priority into account.

In wire electric discharge machining performed with a wire electrode moved relative to a workpiece based on a desired shape, a command speed is controlled so that the discharge densities per unit distance in circular-arc and straight portions of the desired shape are equal, in consideration of the difference in arc length between a circular-arc portion in a desired shape and the corresponding portion of a machining path, whereby the shape accuracy of the circular-arc portion is improved.

A machining path drawing apparatus for a wire electric discharge machine that draws a machining path for the wire electric discharge machine having a core fixation function includes a machining shape information calculation unit for analyzing a machining program to determine machining shape information, a core fixation function operating region detection unit for determining a region where the core fixation function operates in the machining shape information, and a machining path drawing unit for drawing the region where the core fixation function operates with a display attribute changed when a machining path is drawn based on the machining shape information.

When machining of a workpiece is started in a wire electric discharge machine, before a voltage is applied between a wire electrode and the workpiece (a machining gap), practicable shaft feed control systems are discriminated on the basis of machining conditions set in advance. According to the discrimination, running into an inability state of continuity of machining and an accuracy failure after machining are prevented beforehand.

A program generating apparatus includes a machining program generating unit configured to generate a machining program for controlling a wire electrical discharge machine so as to machine a workpiece in accordance with a machining shape of the workpiece input by a user and so as to fix a core which is produced when the workpiece is machined, to the workpiece. In the program generating apparatus, a core handling program generating unit generates a core handling program for controlling a robot so as to remove the core from the workpiece by applying an impact to the core in accordance with the input machining shape of the workpiece.

Electric discharge machining is halted during machining program operation, and a position of the machining halt point is stored. A wire electrode is retreated from the machining halt point to an arbitrary position in which a short-circuit with a workpiece is removed (retreat position), by interrupt operation in which axis movement is performed manually. Then, a return is made from the retreat position to the machining halt point while electric discharge machining is performed, machining program operation is started from the machining halt point, and electric discharge machining is restarted.

A wire electric discharge machine performs electric discharge machining on a workpiece by relatively moving a workpiece placed on a workpiece table and a wire electrode supported by upper and lower wire guides according to a machining program. The wire electric discharge machine comprises an interference determination unit configured to determine whether or not the top or bottom surface of the workpiece table interferes with the wire electrode at the height of the surface during the execution of the machining program.

A machining time-estimating method for a wire electrical discharge machine for estimating the remaining machining time (Tr) during the machining of a workpiece comprises: a step for setting a predicted machining velocity; a step for determining the actual machining velocity; a step for determining an estimated machining velocity so as to incorporate the predicted machining velocity and the actual machining velocity at a specified ratio, that is, a reference ratio; and a step for calculating remaining machining time from the estimated machining velocity. By executing the actual machining velocity-determining step to the remaining machining time-calculating step repeatedly to estimate remaining machining time moment by moment, remaining wire electrical discharge machining time is estimated with reduced error.