Mitsubishi Electric Corporation

Ihi Corporation

Masahiro Okane

Akihiro Goto

Hiroyuki Teramoto

Kazushi Nakamura

Kiyohito Oda

Satoshi Suzuki

Mitsutoshi Watanabe

Hiroyuki Ochiai

Hidetaka Katougi

Yoshinori Asai

An electric discharge machine performs a hole machining on a workpiece by applying a voltage between an electrode and the workpiece to generate an electric discharge therebetween and moving the electrode to a position of a command depth. The electric discharge machine comprises: a storage unit; a current-coordinate detection unit; an electric-discharge-voltage detection unit a penetration detection unit; and a calculation unit. The storage unit stores therein a penetration determination voltage, a penetration determining duration, and a first projecting amount. The current-coordinate detection unit detects a current position of the electrode. The electric-discharge-voltage detection unit detects a minimum voltage of the electric discharge for each predetermined period. The penetration detection unit determines the electrode has penetrated through the workpiece. The calculation unit calculates, a position obtained by adding the first projecting amount to the current position of the electrode detected by the current-coordinate detection unit and updates the command depth.

Electric discharge machine and electric discharge machining method

The present invention is equipped with a series circuit that includes a DC power supply, switching elements and a diode for supplying DC or AC current pulses to a machining gap between a machining electrode and a workpiece, diodes that regulate a direction of the current flow to one direction, and a control unit that controls the switching elements. When the control unit generates a current pulse having a triangular waveform by an inductance that is present in the series circuit, the control unit controls the switching elements in order that a current-pulse time ratio that is a ratio between the non-current time and the current continuation time in the current pulse is equal to or lower than 1/5.

Power supply device for electric discharge machining apparatus and electric discharge machining method

An electrical discharge surface treatment method for forming a coating film by generating a pulsed electrical discharge between an electrode and a workpiece in working fluid or gas using a green compact obtained by molding metal powder or metal alloy powder or a molded body obtained by heating the green compact as the electrode, and by melting an electrode material by an energy of the pulsed electrical discharge, forming a coating of the electrode material or a coating of a material obtained by a reaction of the electrode material by the energy of the pulsed electrical discharge on a surface of the workpiece, the electrical discharge surface treatment method includes generating the pulsed electrical discharge by mixing together two or more types of pulsed electrical discharges having different energies.

Electrical discharge surface treatment method

The present invention includes a series circuit that includes a DC power supply and a switching element for supplying a DC or AC current pulse to a machining gap between a machining electrode and a workpiece; and a control unit that controls the switching element, wherein when generating a current pulse having a triangular shape by an inductance present on the series circuit, the control unit controls on-time and off-time of the switching element such that a peak value of an arbitrary current pulse in a pulse train including a plurality of current pulses changes.

Power supply device for electrical discharge machine

To form a coating film having an excellent wear-resistant property in a temperature range from low temperature to high temperature a coating-film forming method includes a metal-powder producing step of producing a metal powder containing an element exhibiting a lubricating property when oxidized; an oxidizing step of oxidizing the metal powder so that an amount of oxygen contained in the metal powder is within 6 weight % to 14 weight %; and a coating-film forming step of forming a coating film on a material subject to a treatment, the coating film having such a composition that an area where an oxygen content is 3 weight % or less and an area where an oxygen content is 8 weight % or more are distributed in a unit area of the coating film when the metal powder is in a melted state or a semi-melted state, and an oxygen content of the entire coating film after the metal powder is melted or semi-melted being within 5 weight % to 9 weight %.

Growing community of inventors

Chiyoda-ku, Japan

Masahiro Okane