Brother Kogyo Kabushiki-Kaisha

Kunio Kohsaka

Osamu Yamada

Hisaaki Yamane

Akihiro Komori

In a wire electric discharge machine, a permissible discharge frequency is calculated on the basis of an average discharge frequency per unit time which is estimated on the basis of a target inter-electrode voltage or a detected average inter-electrode voltage and a discharge period. The number of times a discharge is actually induced between a wire electrode and a workpiece every unit time is counted and the application of a pulse-shaped voltage is ceased for a residual time of the unit time by a control device when the discharge frequency exceeds the permissible discharge frequency.

Wire electric discharge machine having function for counting number of

The plasma cutting device of the present invention comprises a plurality of release ports for releasing the work gas to prevent adverse influence on the cutting processing besides the exhaust port for jetting the gas toward the work. Accordingly the flow rate and velocity of the swirl flow are increased and the flow rate of the jet gas is still kept the same as that in the conventional device, resulting in stabilizing the plasma arc and performing superior cutting.

Plasma cutting device

A plasma-arc cutting apparatus having a plasma torch producing a plasma arc and cutting a workpiece with the plasma arc, the plasma torch including a nozzle from whcih the plasma arc is ejected toward the workpiece; a feed device moving the plasma torch relative to the workpiece; a magnetic-field forming device producing a magnetic filed, and applying the magnetic field to the plasma arc so as to intersect the plasma arc and thereby deflect the arc; a first control device numerically controlling the feed device according to cutting operation information, the cutting operation information including cutting path data representative of a predetermined curved cutting path along which the plasma torch is moved over the workpiece, the first control means providing torch position data representative of a current position of the plasma torch relative to the workpiece; and a second control device controlling the magnetic-field forming device according to the cutting operation information and the torch position data so that the plasma arc is deflected to an optimum direction with respect to a direction of movement from the current position of the plasma torch as the plasma torch is moved along the curved cutting path.

Plasma-arc cutting apparatus having means for deflecting plasma arc

In a plasma cutting apparatus for cutting a workpiece with a plasma arc, a cutting torch moves relative to the workpiece. The cutting torch produces plasma arc in accordance with a cutting current supplied thereto. To improve surface roughness of the cut facet of the workpiece, a pulsating current is superimposed on a D.C. current to provide the cutting current, wherein the frequency of the pulsating current is controlled in accordance with the moving speed of the cutting torch.

Growing community of inventors

Nagoya, Japan

Kunio Kohsaka