Fanuc Corporation

Tomoyuki Furuta

Akiyoshi Kawahara

Masao Murai

Yasuo Nakashima

Tomoaki Matsunaga

Shinji Yoda

Yasuo Arakawa

Minjie Ai

Yousuke Tsuchiya

A contact detection unit, after executing a first detection operation of contact between the wire electrode and the workpiece at a first relative movement speed and a first pulse cycle, executes a second detection operation of contact between the wire electrode and the workpiece, at a second relative movement speed which is slower than the first relative movement speed, and at a second pulse cycle which is longer than the first pulse cycle, and a movement speed control unit, after execution of the first detection operation, and prior to execution of the second detection operation, causes the wire electrode and the workpiece to relatively move in a distancing direction.

Control device and recording medium encoded with program

A wire electrical discharge machine includes: a voltage application unit for repeatedly applying a voltage to an electrode gap between the workpiece and the wire electrode at a predetermined cycle; a switching element connected in parallel with the electrode gap and configured to short-circuit the electrode gap; and a control section for controlling the switching element so as to short-circuit the electrode gap in a pause period during which the voltage is not applied. The control section adjusts a short-circuiting period in which the electrode gap is short-circuited according to the machining shape specified by a machining program.

Wire electrical discharge machine and control method

A wire electrical discharge machine for machining a workpiece by generating electric discharge at a discharge gap between the workpiece and a wire electrode includes: a machining current setting unit for setting the magnitude of a normal machining current depending on the discharge gap state at application of a discharge induction voltage at the previous time or previous times; and a machining current control unit configured to control a main discharge circuit so as to supply the normal machining current to the discharge gap when the present discharge gap state is the normal state, control the main discharge circuit so as to supply a short-circuit machining current smaller than a predetermined current to the gap when the discharge gap state is the short-circuited state, and control the main discharge circuit so as not to supply any machining current to the gap when the discharge gap state is the open state.

Wire electrical discharge machine and control method of wire electrical discharge machine

A wire electrical discharge machine includes a first voltage applying circuit, a second voltage applying circuit, and a switch controller. The first voltage applying circuit includes a first DC power source for applying a positive polarity voltage across an electrode gap, and a first switch for on/off-switching of application of the positive polarity voltage. The second voltage applying circuit includes a second DC power source for applying a reverse polarity voltage to the electrode gap, and a second switch for on/off-switching of application of the reverse polarity voltage. The switch controller controls the first switch and the second switch so that the first switch and the second switch are not turned on simultaneously. The first DC power source and the second DC power source are set up so that the absolute value of the reverse polarity voltage is lower than the absolute value of the positive polarity voltage.

Wire electrical discharge machine

In a wire electric discharge machine, time from application of a voltage to a machining gap between a workpiece and a wire electrode until occurrence of electric discharge is measured as a discharge delay time, and the measured discharge delay time is integrated over a predetermined measurement period to calculate a discharge delay integrated time. Further, the number of times of the voltage application in the measurement period is counted. An average discharge delay time per voltage application in the measurement period is calculated from the discharge delay integrated time and the number of times of voltage application. The movement of the wire electrode with respect to the workpiece is controlled on the basis of the average discharge delay time.

Wire electric discharge machine including average discharge delay time calculating unit

A cable includes: a linear conductor; a plurality of resin hollow tubes which are disposed around the conductor so that an air layer is formed around the conductor and which extend in a longitudinal direction of the conductor; and an insulating protective member configured to protect the conductor and the plurality of hollow tubes.

Cable

A dielectric working fluid centralized management system is equipped with a dielectric working fluid adjustment apparatus for adjusting the fluid quality of a dielectric working fluid of a plurality of wire electrical discharge machines, a dielectric working fluid delivery and reception control member for controlling delivery and reception of the dielectric working fluid between a plurality of dielectric working fluid storage tanks disposed corresponding respectively to the plurality of wire electrical discharge machines, and in which the dielectric working fluid is stored, and the dielectric working fluid adjustment apparatus, and a dielectric working fluid quality controller, which receives dielectric working fluid information from the plurality of wire electrical discharge machines and controls the dielectric working fluid delivery and reception control member, or both the dielectric working fluid delivery and reception control member and the dielectric working fluid adjustment apparatus.

Dielectric working fluid centralized management system

A wire electrical discharge machine includes: an electrode unit for supplying a machining current to an electrode gap; a switch for changing impedance between a machining power source and the electrode unit; and a controller for, at the time of a core retaining process, controlling the switch to set the impedance to be higher than the impedance in a cutting process and thereby suppressing the machining current flowing through the electrode gap.

A cable includes: a linear conductor; a plurality of resin hollow tubes which are disposed around the conductor so that an air layer is formed around the conductor and which extend in a longitudinal direction of the conductor; an insulating protective member configured to protect the conductor and the plurality of hollow tube; and a partitioning portion provided in at least one hollow tube among the plurality of hollow tubes, the partitioning portion being configured to partition an interior of the hollow tube.

Whether or not an inter-electrode voltage exceeds a voltage threshold is determined after a predetermined inter-electrode state determination period has passed since application of an induction voltage (inter-electrode voltage) to an inter-electrode gap. Thus, an inter-electrode gap amount between a wire electrode and a work is estimated. A pause time during which electrical discharge is not performed is changed according to an estimation result of the inter-electrode gap amount.

Wire electrical discharge machining device

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.

Wire electric discharge machine having shaft feed control system discriminating function

In a wire electric discharge machine, a discharge delay time is used to classify the inter-electrode state into three categories; a short-circuit state, small-gap state, and large-gap state. Based on this classification, the magnitude of a machining current supplied from a main discharge circuit is determined. If the discharge delay time is zero (i.e., if no electric discharge is generated) after the lapse of a predetermined time since the start of the application of a machining voltage to an inter-electrode gap by an auxiliary discharge circuit, the inter-electrode gap is determined to be short-circuited by machining chips. Thereupon, a short-circuit machining current is supplied from the main discharge circuit to the inter-electrode gap to remove the machining chips. In this way, establishment of a complete short-circuit state is prevented so that the machining efficiency is improved to increase the machining speed.

Wire electric discharge machine

In a power supply device for electric discharge machining, the polarity of the voltage to be applied is determined on the basis of a result of determination whether the machining gap is in open state or not, an average value of voltages applied across the machining gap voltage during machining, and the number of successive open states with the same polarity. This eliminates the need to significantly vary the voltages to be applied from positive to negative and from negative to positive, thereby reducing the output energy required by the machining power supply.

Growing community of inventors

Yamanashi, Japan

Tomoyuki Furuta