Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Mitsubishi Electric Engineering Company, Limited

Atsushi Taneda

Takashi Hashimoto

Akihiro Goto

Akihiko Iwata

Tatsushi Sato

Akihiro Suzuki

Yoshio Ozaki

Hajime Ogawa

Satoshi Suzuki

Hideaki Hayashi

Takashi Yuzawa

Taichiro Tamida

Yoshihito Imai

Hidetaka Miyake

Yasuo Onodera

Yoshikazu Tsunoda

Yoshikazu Ukai

Yoshihide Kinbara

Koji Akamatsu

Toshiaki Tanaka

Toshio Nakashima

Tamayo Ohata

Kouichirou Hattori

Kazuhiko Uemoto

Morihisa Nishikawa

Masahiro Nakata

Kooji Akamatsu

Based on a discharging gap value and machining allowance value stored in a corner-control-information storing means, a speed-ratio calculating meansbeing a machining-volume calculating means calculates machining volumes of a straight line portion and a corner portion to calculate a volume ratio therebetween. A corner-portion-speed calculating meanscalculates a machining feed speed at the corner portion based on a volume ratio calculated by the speed-ratio calculating means, and then outputs to a servo amplifieron the basis of the length of a pre-corner section outputted by a pre-corner-section calculating meansand the length of a post-corner section outputted by a post-corner-section calculating means, instructions about machining feed speeds from entering the pre-corner section till getting out of the post-corner section.

Wire electric discharge machine and wire electric discharge machining method

A power supply unit for wire electrical discharge machining using an ac high-frequency power supply for applying an ac high-frequency voltage between a wire electrode (1) and a workpiece () includes a high-frequency oscillation and amplification circuit () and a pulse power supply () which is an ac-high-frequency-voltage intermittently supplying unit for effecting the application of the ac high-frequency voltage between the electrode and the workpiece and a pause thereof. In wire electrical discharge machining using this power supply unit for wire electrical discharge machining, it is possible to suppress the vibration of the wire electrode (1) due tog the electrostatic force acting between the wire electrode (1) and the workpiece (), making it possible to improve the straightness accuracy of a machined surface of the workpiece () and make surface roughness small.

Power supply unit for wire electrical discharge machining and method of wire electrical discharge machining

An electric discharge machine in which electric power for working is supplied between an electrode and workpiece by an electric power unit so as to generate electric discharge between the electrode and workpiece and conduct machining on the workpiece, the electric discharge machine having a voltage detector for detecting output voltage V of a DC electric power source of the electric power unit; a current detector for detecting output current I of the DC electric power source of the electric power unit; a calculator for calculating product V&middot;I of V and I; and a controller for controlling output electric power of the electric power unit to be constant on the basis of a difference between a working command signal for giving a predetermined electric power command and V&middot;I. Even when load impedance fluctuates, it is possible to suppress the fluctuation of electric discharge power, so that surface roughness on a machined face of the workpiece can be made uniform.

Electric discharge machine with output power control

An electric discharge machining apparatus includes a wire electrode for machining a workpiece, and a first voltage applying unit for applying a voltage pulse. The voltage pulse has a rise time longer than a discharge formative time lag when a rectangular voltage pulse is applied, when a distance between the workpiece and the wire is an average value in machining, and rises to the same voltage as the rectangular voltage pulse.

Electric discharge machining apparatus generating preliminary discharge and machining discharge pulses

An electric discharge machine apparatus has a numeric control unit which can optimally set jumping conditions without forcing the user to perform any complicated setting operation. The numeric control unit calculates an optimal jumping velocity from a value indicating a machine-allowable load for the electric discharge machining apparatus, a machining area according to the electric discharge machining conditions, and a machining gap length computed from the electric discharge machining conditions. The machining area is computed by the ratio between the proceeding velocity in machining and a discharge pulse frequency. The machining gap length is computed according to the current value of a machining current pulse as well as to a voltage loaded to the machining gap.

Electric discharge machining apparatus

A power supply unit for a discharge machining apparatus which eliminates overshooting in current rise and improves the electrode consumption characteristics by preventing an operational amplifier as well as a current control element from being saturated, thereby eliminating overshooting during the rise time of the machining current, by clamping the output voltage of the operational amplifier during the stand-by time for electric discharge. The output is clamped by a plurality of resistors and diodes to a state where the output voltage is higher than a power-supply voltage (the output clamp level is set by a resistor). Namely, during the stand-by time when inverted amplification (feedback) via a resistor in an operational amplifier is being carried out, a constant state of feedback is maintained by the diodes.

Power supply unit for discharge apparatus which prevents excessive

In a power supply apparatus of an electrical discharge machine, a power supply high in efficiency and small in current ripple is provided to achieve a power supply reduced in size and price. In addition, a switching power supply system is used jointly to generate an optional waveform. A first switching device is switched on/off in an optional cycle under the control of a current command value signal corresponding to the waveform shape of a current pulse to be supplied to a machining gap, whereby an optional shape of current pulse is supplied to the machining gap and a current component which compensates for a current ripple generated by said switching at the time of supplying said current is superimposed on said optional shape of current pulse and is supplied to the machining gap.

Method and apparatus for controlling the power supply for electrical

A method and apparatus for detecting and controlling the operation of an electric discharge machine for machining a workpiece. The machining is conducted by generating pulse discharges at a machining gap formed by a machining electrode and the workpiece opposed to each other. The alternating-current components or high frequency components of at least one of the current, voltage and impedance of the machining gap, the rectified components thereof, or amplitude, frequency or other signal characteristics thereof are detected and processed for control of the machining. The processing may include frequency analysis, pulse counting, threshold detection and the like using analog and digital processing.

Electrical discharge machine and machining method therefor

An electronic discharge machining system in which an electrode and workpiece are coupled between first and second power supply circuits. The first power supply circuit includes a DC power source, a switching element, and a current limiting resistor, which are controlled by a control circuit. The second power supply circuit includes a machining gap status detecting DC power supply, which is composed of a voltage source and a controllable output impedance, and a switching element, all of which are controlled by a control circuit. The secondary power supply circuit is controlled by the control circuit, which sets and controls the voltage source and/or the output impedance of the machining gap status detecting DC power supply in accordance with machining conditions, such as the voltage detected across the machining gap.

Electric discharge machining system having a secondary power supply

Wire electrode feeding device in wire cut electric discharge machine

An interelectrode distance controlling device in an electric discharge machining apparatus which is capable of automatically setting the proportional constant for a drive unit for driving an electrode to machine a workpiece, so that the machining is performed with high accuracy and smoothly. Such an interelectrode distance controlling device, detects the oscillation of a system in an electric discharge machining apparatus during machining, and the device automatically sets the proportional constant to an optimum value in a range within which no oscillation occurs with the system.

Interelectrode distance controlling device in electric discharge

Electric discharge machining method and device

Growing community of inventors

Aichi, Japan

Atsushi Taneda