Provided is a wire electrical discharge machining device which has a tension controller for maintaining the tension of a traveling wire electrode at a tension. The tension controller includes: an allowed tension calculation module for determining an allowed tension that is less than a wire breaking tension at which the wire electrode breaks; and a set tension generation module for generating the set tension in accordance with the allowed tension. When the set tension is greater than the allowed tension, the set tension generation module reduces the set tension. When the set tension is less than the allowed tension, the set tension generation module increases the set tension in such a way that the set tension does not exceed the allowed tension.

A threading nozzle for threading a wire electrode for a threading device in a wire electrical discharge erosion machine includes a threading-nozzle body having a guide bore configured to guide the wire electrode along a longitudinal axis of the former and a gap that splits the threading-nozzle body in two parts which are connected at a flexural hinge configured in the threading-nozzle body. The gap splits the guide bore in two parts.

An object of the present invention is to accurately position a wire electrode and a work. A control device included in a wire electric discharge machine of the present invention causes, in a state in which movement of the wire electrode in a longitudinal direction is stopped, a capacitance measuring section to measure capacitance while causing a driving section to relatively move a wire electrode and a work, thereafter causes, in a state in which the control device causes a wire moving section to move the wire electrode in the longitudinal direction, the capacitance measuring section to measure the capacitance, and causes the driving section to adjust relative positions of the wire electrode and the work.

An object of the present invention is to accurately position a wire electrode and a work. A control device included in a wire electric discharge machine of the present invention causes, in a state in which movement of the wire electrode in a longitudinal direction is stopped, a capacitance measuring section to measure capacitance while causing a driving section to relatively move a wire electrode and a work, thereafter causes, in a state in which the control device causes a wire moving section to move the wire electrode in the longitudinal direction, the capacitance measuring section to measure the capacitance, and causes the driving section to adjust relative positions of the wire electrode and the work.

A wire cut electric discharge machining apparatus cannot maintain high machining accuracy because the arm may expand/contract as it receives more heat from the machining fluid. The wire cut electric discharge machining apparatus has guide parts that guide a wire and arms that support the guide parts, wherein at least one of the guide parts has a machining fluid ejection nozzle, and at least one of the arms has an ejection connection pipe and a thermal insulation part. The ejection connection pipe is a hole penetrating the arm and supplies the machining fluid to the machining fluid ejection nozzle, and the thermal insulation part covers the inner peripheral surface of the ejection connection pipe to thermally insulate the inner hole of the ejection connection pipe.

It is provided an electrolysis and grinding combined machining device and method. The device includes a machine tool bed, a vertical moving mechanism and a horizontal moving mechanism which are provided on the machine tool bed. An electrode clamping device is provided on the vertical moving mechanism, and the electrode clamping device is configured to fix a tool electrode. An electrolysis tank is provided on the horizontal moving mechanism. A workpiece to be machined is placed in the electrolysis tank. The tool electrode includes a metal wire and abrasive materials distributed on a surface of the metal wire. The tool electrode and the workpiece to be machined are electrically connected with a pulse power source. A current sensor is arranged between the workpiece and the pulse power source. A data acquisition card is connected to the current sensor; the data acquisition card is electrically connected with an industrial personal computer.

It is provided an electrolysis and grinding combined machining device and method. The device includes a machine tool bed, a vertical moving mechanism and a horizontal moving mechanism which are provided on the machine tool bed. An electrode clamping device is provided on the vertical moving mechanism, and the electrode clamping device is configured to fix a tool electrode. An electrolysis tank is provided on the horizontal moving mechanism. A workpiece to be machined is placed in the electrolysis tank. The tool electrode includes a metal wire and abrasive materials distributed on a surface of the metal wire. The tool electrode and the workpiece to be machined are electrically connected with a pulse power source. A current sensor is arranged between the workpiece and the pulse power source. A data acquisition card is connected to the current sensor; the data acquisition card is electrically connected with an industrial personal computer.

A wire electric discharge machining apparatus is provided. The wire electric discharge machining apparatus includes an upper support that supports an upper guide unit that guides a wire electrode on an upper side. The upper support includes an arm having a lower end provided with the upper guide unit, an axis drive portion moving the arm in at least one axial direction and made of a material that has a larger coefficient of linear expansion than ceramics, and an adjustment block connecting the arm and the axis drive portion and made of ceramics. The adjustment block is fixed at a position where a displacement of the upper guide unit caused by expansion and contraction of the upper support is suppressed by a bimetal effect occurring on a fastening surface of the axis drive portion and the adjustment block.

A wire electric discharge machining apparatus is provided. The wire electric discharge machining apparatus includes an upper support that supports an upper guide unit that guides a wire electrode on an upper side. The upper support includes an arm having a lower end provided with the upper guide unit, an axis drive portion moving the arm in at least one axial direction and made of a material that has a larger coefficient of linear expansion than ceramics, and an adjustment block connecting the arm and the axis drive portion and made of ceramics. The adjustment block is fixed at a position where a displacement of the upper guide unit caused by expansion and contraction of the upper support is suppressed by a bimetal effect occurring on a fastening surface of the axis drive portion and the adjustment block.

A device for machining a part by electrical discharge machining using an electrode wire. The device includes equipment for holding the electrode wire taut and driving the wire to translate longitudinally, in proximity to the part to be machined, in a sparking zone. The device further includes equipment for making a stream of dielectric liquid flow through the sparking zone between the electrode wire and the part to be machined. An electrical power source generates electrical pulses that cause sparks in the sparking zone between the electrode wire and the part to be machined. The quantity of gas bubbles present in the sparking zone is measured, and a signal is produced, representative of the quantity of bubbles, the signal being delivered to a controller. The controller modifies machining parameters so as to maintain the value of the signal within a suitable range.