Abstract:
A method of and an apparatus for machining an electrically conductive workpiece with a wire electrode which is originally ferromagnetic or becomes ferromagnetic in the machining zone wherein the magnetic properties of the wire are detected as it passes out of the machining zone and the detected magnetic properties are used to control a machining parameter.
Abstract:
AT (automatic threading) of wire through a workpiece without the need for a preformed through-hole therein is achieved on a TW (traveling-wire) electroerosion machine (TW-E machine) by utilizing a tubular electroerosion electrode positioned in axial alignment with a wire-threading path. Wire from a wire supply is introduced into the tubular electrode so as to extend through a tool holder therefor. The tubular electrode is advanced along the wire-threading path into and through the workpiece while electroerosively forming a bore therein. Wire is dispensed from the supply to allow wire to move out of the tubular electrode while the latter at least partially remains in the bore so that the wire passes into the wire outlet side of the cutting zone towards a takeup assembly. The tubular electrode may then be retracted along the wire-threading path from the workpiece while leaving wire in the bore finished in the workpiece.
Abstract:
A measuring system using the magnetic scale and a sensing head measures a deformation of a deformable member and/or one or more physical quantities, e.g. a strain and internal stress of, or an external force to, the member, which are functions of the deformation. The magnetic scale comprises a succession of discrete, uniformly spaced scaling units each of which individually consists of a pair of magnetic poles (N, S). The magnetic scale is arranged to be displaceable relative to the magnetic sensing head in response to a deformation of the deformable member so that the magnetic pickup head successively senses the passage of the magnetic scaling units. An output circuit unit is connected to the magnetic head for counting the number of magnetic scaling units sensed corresponding to the deformation and produces an electrical output signal representative thereof, and/or one or more of the above physical quantities.
Abstract:
A safety system for a machine tool, e.g. an EDM machine, having a multiplicity of different items of setting procedure to be attended to manually and inspected by the operator before the machine is actuated for performing a given machining operation, employs a loudspeaker associated with the machine. A control unit is used to produce a preselected sequence of multiple, time-spaced electrical signals corresponding to multiple verbal instructions prescribed for alerting the different setting items, respectively, and to apply these signals in that sequence to an electromechanical transducer in the loudspeaker. The transducer responsive to each of the electrical signals produces through the loudspeaker a corresponding unit of the multiple verbal instructions audible to the operator for a corresponding item of the setting procedure. A manual switch is provided so as to be actuated by the operator upon his checking of the item to produce an OK signal therefor, which is applied to the control unit to allow a next of the electrical signals in the prescribed sequence to be issued, thereby permitting the loudspeaker to emit a next corresponding unit of the multiple verbal instructions audible to the operator for a next corresponding item of the setting procedure.
Abstract:
An EDM method and apparatus, utilizing a generic electrode, i.e. a tool electrode independent in shape of a desired cavity or contour to be machined in a workpiece, and utilizing a three-dimensional machining feed displacement, makes use of an assembly for maintaining the contamination of the machining liquid with machining products, e.g. chips and gases, at a certain enhanced level. The assembly includes a pad or block member disposed in the proximity of the workpiece with a small spacing therewith while surrounding the generic electrode to mechanically control or limit discharging of the machining products out of the EDM gap, thereby enabling a stabilized production of machining electrical discharges across the EDM gap maintained substantially constant.
Abstract:
Wire-cut electroerosion method and apparatus whereby breakage of an electrode wire is substantially prevented by limiting air-bubbling in the cutting zone from the electrode wire traveling through a liquid-machining medium. The air-bubbling is limited by cleaning the electrode wire advancing from its storage reel prior to its entry into the cutting zone supplied with the liquid machining medium. The electrode wire may be cleaned by brushing the wire between the storage reel and the wire-braking roller and thereafter cleansed by a showering fluid. Preferably, ultrasonic vibrations are applied to the showering fluid. The braking rollers and a wire-conducting roller are also provided with brushes to prevent contaminants from being introduced onto the cleaned electrode wire by these rollers.
Abstract:
A capacitor-type power supply for electrical machining has a capacitor connected across a machining gap and in the region thereof while a high-frequency power generator is disposed at a location remote from the machining gap and provides a high-frequency electric power. A feeder connects the power generator with the capacitor to permit the capacitor to be charged with pulses of the high-frequency electrical power. The system permits the high-frequency source to be located distally from the machining gap.
Abstract:
A novel method of polishing a workpiece surface comprises passing over the surface in elastically compressive abrasive contact therewith a mass of discrete, elastically deformable pieces each individually consisting of a matrix of elastomeric material containing finely divided abrasive particles substantially uniformly distributed at least along a surface region of the individual piece.
Abstract:
A method of and an apparatus for electrical-machining a conductive workpiece with an axially traveling wire electrode displaced transversely to the workpiece along a predetermined cutting path to advance electroerosion effected across the machining gap supplied with a machining liquid, wherein the rate of supply of the machining liquid to the gap is controlled as a function of the shape of the cutting path.
Abstract:
An improved machining method and electrode for use in the traveling-wire EDM process utilizing an aqueous machining fluid medium which is decomposed by erosive electrical discharges into gaseous oxygen and hydrogen. Breakage of the traveling-wire electrode is reduced or eliminated through the use of an improved electrode element comprising a continuous electrode wire substrate and a layer of a polymeric substance having a temperature of thermal decomposition of 100.degree. to 500.degree. C. attached thereto in a distributed manner such as to partially cover the surface of the substrate. The improved electrode element traveling in machining juxtaposition with the workpiece is subjected to the electrical discharges to cause a thermal decomposition of the polymeric substance to form carbon and to allow the gaseous oxygen and hydrogen at least partially to be chemically combined therewith and to reduce the amount of the oxygen gases in the machining gap which tend to cause a continuous arc discharge or explosion as a cause of the wire breakage. The improved elongate element should preferably contain a hydrogen active catalytic metal, e.g. Li, Cs or Sm, having a spectrographic wavelength of 300 to 600 nm to facilitate chemical reaction of carbon with oxygen and hydrogen in the gap.