Mitsubishi Denki Kabushiki Kaisha

Nippon Kokan Kabushiki Kaisha

Yukio Kato

Mitsugi Kawano

Tetsuro Urata

Kunihiko Sato

Takeo Uebayashi

Tetsuhiro Asamoto

Terumasa Jinba

Katsumi Michishita

Fujio Aoshima

Kenji Kawaguchi

Seigo Hiramoto

Kobun Asakawa

Osamu Hamada

Haruo Taguchi

Kozo Yamada

There is disclosed a device for electrical discharge machining of a work in the form of a roll for providing a satinized indented surface by satinizing operation to a predetermined surface roughness, wherein two rows of heads each mounting one or more electrodes are mounted on either sides of the rotary axis of the roll for increasing the number of heads and thereby reducing the working time. One of the rows of heads is movably mounted on a shaft on the side of roll handling operation of the roll for transiently displacing the heads in their entirety to an out-of-the-way position for solving the problem caused by roll handling and by the increase in the number of heads.

Device for electrical discharge machining of a work in the form of a roll

There is disclosed a method for electrical discharge machining of a workpiece in the form of a roll by application of an electrical voltage across said workpiece and an electrode or electrodes mounted opposite to each other with a predetermined gap therebetween, and more particularly such method wherein each such electrode is formed by plural electrode segments separated from one another by insulators, and the electrical discharge operation is performed with said electrode segments in each electrode short-circuited to one another in the rough machining step and with said electrode segments insulated from one another in the finish machining step for reducing the working time.

EDM Of a roll using segmented electrode short-circuited in the rough

A process for preparing a press die comprises forming a metal overlaid on a base metal which is different in kind from the overlaid metal, and cutting the base metal together with overlaid metal into a predetermined shape.

Process for preparing a press die

Disclosed is an electric discharge machining method in which the electric discharge working gap between an electrode and a work piece to be machined is automatically adjusted. To detect the condition of the discharge working gap, a low voltage pulse is applied each time a plurality of high voltage pulse for electric discharge machining are applied for a predetermined time. The working current resulting from the application of each low voltage pulse is detected to control the feeding of the electrode and thereby to automatically adjust the discharge working gap to a predetermined value.

Method and apparatus for adjusting the gap in an electric discharge

There is disclosed a method for giving by electrical discharge machining a uniform satin finish to the roll surface of a work in roll form in a short period of time. To prevent the occurrence of any streaky pattern on the satin finish work surface, a plurality of divided electrodes, which are divided and arranged at predetermined spaces, are each fed traversely a distance corresponding to the electrode mounting pitch while maintaining the predetermined spacing between the electrodes. To improve the working efficiency, a plurality of rows of divided electrodes are provided, and by virtue of this improved working efficiency, the required satinizing electrical discharge machining of two or four rolls for use on a rolling mill can be completed within the life time of the satinized rolls being used on the rolling mill.

Method for electrical discharge machining of a work in roll form

There is disclosed an apparatus for giving a satin finish to the surface of a crowned roll. A plurality of electrode heads are divided and arranged along the axis of rotation of the crowned roll to be worked, and one or a plurality of rectangular electrodes are mounted at a predetermined spacing on each of the electrode heads. The discharge gap of each rectangular electrode is controlled by a servomechanism at a predetermined value and it is also fed traversely a predetermined distance by a traverse feed mechanism. The electrode is rectractably mounted on the electrode head and it is fixed in position so that the discharge surface of the electrode is projected into contact with the roll surface of the crowned roll. The discharge electrode surface of each rectangular electrode is initially flat and this discharge surface is consumed to conform with the shape or contour of the roll surface upon initiation of discharge.

Growing community of inventors

Kasugai, Japan

Yukio Kato