A method and device for electrical discharge machining (EDM) a workpiece by means of a train of machining pulses. During the machining time the machining pulses are applied to the working gap between workpiece and electrode. An open voltage is first applied, and it is increased to a second open voltage level if a discharge does not occur within a waiting time d.sub.0, and further increased to a third open voltage level if a discharge does not occur within a second waiting time d.sub.1.

An average product of the actual open voltages times the partial ignition delays is computed and subtracted from the product of a reference open voltage times the total ignition delay, and the servo setpoint value is adjusted accordingly. The actual axes positions are sampled in real time and the discharge electrical parameters are adjusted accordingly. The discharge electrical parameters can be adjusted according to the duration of d0 and d1.

A method for generating cavity model applied for machining a part by electrode discharge machine (EDM) using a tool electrode comprising: a. generating a part-before EDM model defining the geometry of a part to be eroded by the EDM machine to obtain a final part; b. generating an electrode model defining the geometry of the electrode applied for eroding the part; c. computing a cavity model defining the geometrical shape of a cavity, which represent the volume of the material to be eroded by the erode based on the part-before EDM model and the electrode model.

A machine tool includes a ram extending in a longitudinal direction and being disposed horizontally, a processing head attached to the ram, a tower connected to the ram in a state of upwardly standing at an intermediate position in the longitudinal direction of the ram and having an adjustable height, a front arm connected to a front portion of the ram, and a rear arm connected to a rear portion of the ram. The tower includes a base portion fixed to the ram, an arm connection portion connecting the front arm and the rear arm, and a jack-up bolt. The jack-up bolt is in contact with one of the base portion and the arm connection portion in a vertical direction, and threadingly engaged to the other one of the base portion and the arm connection portion. The jack-up bolt pushes the arm connection portion upwardly by screwing or unscrewing.

A machine tool includes a machining unit for feeding cutting oil to a work surface of a workpiece and machining the work surface, an optical sensor body unit dividing light outputted from a frequency sweep light source for outputting light whose frequency varies periodically into irradiation light with which the workpiece is to be irradiated and reference light, irradiating the workpiece with the irradiation light, detecting a peak frequency of interference light between reflected light which is irradiation light reflected by the workpiece, and the reference light, and measuring the distance from the machine tool to the work surface on the basis of the peak frequency, and a shape calculation unit calculating the shape of the workpiece on the basis of the distance measured by the optical sensor body unit.

Electrodes for and methods of electrical discharge machining are provided. For example, a method for forming a feature in a ceramic matrix composite (CMC) component comprises repeatedly advancing an electrode into and retracting the electrode from the CMC component until a desired depth is reached, where the electrode has a head end, a tip end, and a shaft extending from the head end to the tip end. The shaft has a first side and a second side each recessed inward such that the head end and the tip end are wider than the shaft. A method for forming a feature in a CMC component also may include feeding a dielectric fluid into the feature utilizing the recessed sides. In some embodiments, electrodes may include a shaft extending from a head end to a tip end and a central plane, where the shaft is recessed widthwise toward the central plane.

A machine tool includes a ram extending in a longitudinal direction and being disposed horizontally, a processing head attached to the ram, a tower connected to the ram in a state of upwardly standing at an intermediate position in the longitudinal direction of the ram and having an adjustable height, a front arm connected to a front portion of the ram, and a rear arm connected to a rear portion of the ram. The tower includes a base portion fixed to the ram, an arm connection portion connecting the front arm and the rear arm, and a jack-up bolt. The jack-up bolt is in contact with one of the base portion and the arm connection portion in a vertical direction, and threadingly engaged to the other one of the base portion and the arm connection portion. The jack-up bolt pushes the arm connection portion upwardly by screwing or unscrewing.

A method for producing cavities in a turbomachine disk, the cavities extending between first and second lateral surfaces of the disk, the method including positioning a ring facing the first surface, the ring including an inner periphery including protrusions complementary in shape to the cavities that are to be produced; circulating an electrolyte close to the protrusions on the ring; activating a first translational movement of the ring towards the second surface; activating a rotation of the disk; generating an electric current pulse in the electrolyte when the ring is substantially at the first surface, the pulse resulting in the ionic dissolution of the disk at the protrusions; reducing the speed of rotation to a first reduced speed, when the ring is substantially at the first surface, for a first period of time; and stopping the first translation of the ring when the ring is beyond the second surface.

An object is to provide a graphite-copper composite electrode material that is capable of reducing electrode wear to a practically usable level and to provide an electrical discharge machining electrode using the material. A graphite-copper composite electrode material includes a substrate comprising a graphite material and having pores, and copper impregnated in the pores of the substrate, the electrode material having an electrical resistivity of 2.5 m or less, preferably 1.5 m or less, more preferably 1.0 m or less. It is desirable that the substrate comprising the graphite material have an anisotropy ratio of 1.2 or less. It is desirable that an impregnation rate of the copper in the electrode material is 13% or greater. It is desirable that the substrate comprising the graphite material have a bulk density of from 1.40 Mg/m.sup.3 to 1.85 Mg/m.sup.3.

Electrodes for and methods of electrical discharge machining are provided. For example, a method for forming a feature in a ceramic matrix composite (CMC) component comprises repeatedly advancing an electrode into and retracting the electrode from the CMC component until a desired depth is reached, where the electrode has a head end, a tip end, and a shaft extending from the head end to the tip end. The shaft has a first side and a second side each recessed inward such that the head end and the tip end are wider than the shaft. A method for forming a feature in a CMC component also may include feeding a dielectric fluid into the feature utilizing the recessed sides. In some embodiments, electrodes may include a shaft extending from a head end to a tip end and a central plane, where the shaft is recessed widthwise toward the central plane.

In the present disclosure, the high-pressure chamber includes a chamber main body including a flat rectangular parallelepiped block of a metal which is formed with a flat cavity that serves as a substrate processing space in which a processing using a high-pressure fluid is performed on a substrate, and the substrate processing space being formed by machining the block from one of faces of the block other than the widest face towards another face opposing thereto. In a case where the cavity is constituted as a through hole, the though hole is provided with a cover configured to open or close the cavity on one side of the through hole, and a second block configured to air-tightly seal the cavity on the other side.