Abstract: A traveling-electrode electroerosion apparatus using a pair of wheeled carriages which accommodate axial electrode drives and machining feed drives. The wheeled carriages also carry a pair of guide members for establishing a straight-line path for the electrode to travel through the workpiece. The axial drives used to maintain the electrode in traveling alignment with the straight-line path serve in this improvement to generate a tension force acting on the traveling electrode to force one of the wheeled carriages against one of two parallel surfaces and the other of the wheeled carriages to the other of the surfaces, thereby intensifying their respective frictional engagement with these surfaces, e.g. the upper and lower surfaces of the workpiece which may be massive.

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 NC-EDM method and apparatus wherein a succession of electrical discharges is effected across an EDM gap to effect electroerosive stock removal from the workpiece while the tool electrode is consecutively advanced relatively into the workpiece under NC commands which in a prescribed set define a desired path and extent of the relative advancement. Control is effected to act on the EDM power supply for maintaining parameters of the electrical discharges in a given EDM mode during an initial period of the consecutive advancement of the tool electrode relative to the workpiece. The arrival of the tool electrode at a predetermined position relative to the workpiece spaced by a preselected distance from its final position which is determined by the said extent of the consecutive relative advancement is sensed for switching the parameters of the electrical discharges into another EDM mode and maintaining the switched parameters until the tool electrode reaches the said final position relative to the workpiece.

Abstract: A feedpath deviation preventive NC path-controlled machining system in which a plotting unit is used, in a preliminary operation in advance of a machining operation, to produce on a record medium a continuous plot equivalent to a programmed machining feed path to be followed by relative displacement between the tool member and the workpiece during the machining operation. In the latter, a sensing head is disposed in sensing relationship with the plotted record medium for relative displacement to the latter jointly with the relative displacement between the tool member and the workpiece. The sensing head continues to trace the continuous plot as long as the actual machining relative displacement proceeds along the programmed machining path to produce an OK signal.

Abstract: A traveling-wire (TW) electroerosion apparatus in which at least one of wire guides which are disposed at opposite sides of the cutting zone includes a plurality of elementary guide members arranged one adjacent to another in the direction of wire travel and having wire-receptive notches, the notched members being staggered to make up a composite guide opening of these notches such that the diameter of an imaginary cylinder which can be inscribed therein is substantially equal to the nominal wire diameter. Preferably, the elementary guide members are arranged to be displaceable relative to one another and in their respective planes, which are parallel to one another, to change the positions of these guide notches and thus to change the diameter of the imaginary cylinder.

Abstract: An NC-EDM machine is safeguarded against feed errors arising from both mechanical and erosive-machining effects. The disclosed safety arrangement includes two detecting circuit units. The first unit is arranged to respond to NC-furnished driving command signals for producing a first detection signal representative of a commanded relative displacement to be effected between the tool electrode and the workpiece along a programmed machining path in a given time period. The second detecting unit is arranged to respond to effective electrical discharges caused in the EDM gap to produce a second detection signal representative of an actual relative displacement effected between the tool electrode and the workpiece along the path in the given time period. A comparator is connected to the two detecting units for comparing the first and second detection signals to produce an output signal indicative of a deviation of the actual advancement from the commanded advance.

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 workpiece cutting method and apparatus in which an elongated wire or band tool spans a pair of guides and is continuously advanced relative to the workpiece by a first drive system but is reciprocated in the region of the workpiece by a second drive system at higher speed than the rate of continuous advance. This is permitted by storage devices between each guide and the first drive. The tool can carry out electrical machining and/or abrasive cutting using an abrasive bonded to the tool or in a machining fluid introduced into the cutting region.

Abstract: A method of and an apparatus for machining interfitting members to improve their fit wherein the members are positioned to place their surfaces to be interfitted in a complementary relationship with a small gap spacing therebetween. A fluid delivery assembly includes a manifold supplied with a pressurized EDM liquid medium from a source thereof and a plurality of nozzles having each a respective valve and commonly projecting from the manifold. The nozzles have their respective nozzle outlets arranged in an array so as to be disposed individually adjacent to and distributed uniformly in the array along a continuous opening or slit formed as a continuous, narrow and elongate outlet opening of the gap spacing between the members where the surfaces to be interfitted terminate.

Abstract: A machining center or system for shaping workpieces, having a numerical controller (NC) for transmitting control commands in accordance with input data. A principal tool has a tool holder and a numerically controlled machining feed unit for shaping a workpiece under the numerical commands. A tool storage station accepts a plurality of formed machining tools and a tool changing mechanism interconnects the tool storage station and the principal machine tool. The center incorporates a tool reforming station which responds to a set of numerical commands from the NC unit to act on a formed machining tool when on one of the tool storage station, the tool changing mechanism and the tool holder in the principal machine tool.

Abstract: An EDM system in which a tool electrode is spacedly juxtaposed with a workpiece to define a machining gap which is substantially open directly to a region of atmospheric air. A non-inflammable (e.g. water-based) machining liquid is injected into the machining gap while electrical discharges are effected therein to electroerosively remove stock from the workpiece and to permit the injected liquid to be at least partially decomposed with a resultant formation of machining products which, growing in amount, are accumulated in a pile as debris on a surface of the workpiece adjacent the machining gap. A brush is provided to sweep the debris, and to substantially remove the piled machining products adjacent the machining gap.

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 machining center utilizing a traveling-electrode EDM machine in which a thin, continuous electrode element is supplied, transported, guided over a guide member and taken up to provide a continuously renewed span of electrode surface traveling over the guide member juxtaposed in electroerosive relationship with a workpiece. The guide member has a guide surface formed to impart a preselected geometry to the span of the electrode element and is detachably secured to a guide holder in the machine. The machining center includes a guide storage station for accepting a plurality of guide members the guide surfaces of which are different in geometry. A guide-member-changing device is operatively associated between the storage station and the machine to exchange guide member therebetween.

Abstract: A new method is disclosed for the electroerosion machining of a workpiece by employing as a machining fluid, raw water which has been deionized until its resistivity increases to at least 10.sup.5 ohm-cm and then decreasing the resistivity of the raw water deionized previously by adding thereto a conductivity modifier substantially free from chloride ions, said conductivity modifier being added to said deionized water in an amount sufficient to impart to the resulting machining fluid a predetermined conductivity.

Abstract: A wire state of use indication apparatus for use with a traveling-wire electroerosion cutting machine is disclosed in which a sensing unit instantaneously responds to the rotation of a roller disposed in the wire travel path and rotated with the electrode wire travelling in bearing contact with the roller. The number of the rotations is counted to produce a sensing signal which represents the cumulative number of rotations of the roller a number which in turn represents the amount of the electrode wire which has been drawn out of the wire storage rool by a given time instant during a given cutting operation. A processing circuit is provided to process the sensing signal with an input setting signal representing the amount of the electrode wire stored in the reel prior to the commencement of the cutting operation to produce an output signal which represents the amount of the electrode wire remaining in the reel at that time instant.

Abstract: A method of and an apparatus for the electroerosive machine of a workpiece in which a tool electrode, such as a traveling wire, traverses a nozzle which coaxially directs into the machining gap a mixture of water vapor and liquid water. The liquid water is drawn into the nozzle by the suction created by the passage of steam therethrough and the proportions of liquid water and water vapor in the machining fluid are controlled in response to gap conditions. The water vapor or steam is generated by heating a body of water in the apparatus.

Abstract: An electrical machining method and apparatus in which a gaseous effluent containing noxious or unacceptable gaseous components is evolved from the electrical machining gap and is collected in a space immediately above the gap flooding electrical machining liquid and confined from direct escape into the atmosphere. This space or chamber is arranged to communicate with the atmosphere via an elongated fluid conduit for drawing the collected gases into the atmosphere. A laser generator irradiates the flowing gases with a laser beam to decompose the noxious components into their constituent elements. Mirrors for the laser beam may be vibrated to laterally oscillate the laser beam, thereby enhancing the efficiency of the laser irradiation and the resulting gas detoxification.

Abstract: A traveling-wire electroerosion apparatus using a first nozzle disposed at one side of a workpiece so as to coaxially surround the electrode wire moving into the workpiece for directing under a relatively low pressure a cutting liquid medium into a cutting zone in the workpiece and a second nozzle disposed at the other side of the workpiece so as to coaxially surround the electrode wire moving from the workpiece for directing under a relatively high pressure the cutting liquid medium into the cutting zone. A liquid flow guidance member, generally in the form of an annular disk or discus, is disposed at that one side of the workpiece and adjacent thereto so as to overlie at least a region of the cutting slot generated behind the advancing electrode wire, which region is adjacent the nozzle opening of the first nozzle.

Abstract: An inner movable nozzle and an outer movable nozzle are slidably supported by a hollow base member having a first and a second internal fluid passage flooded with a pressurized machining liquid medium in a first and a second inlet flow, respectively. The inner nozzle is constituted by a first hollow body surrounding a traveling electrode and ending with an outlet portion forming a first annular face adjacent the workpiece and defining a principal nozzle orifice for discharging the liquid medium of the first flow about the electrode. The hollow body is movably supported by the base member so as to be thrusted outwards thereof to urge the outlet portion towards engagement with the workpiece against pressure in constituted fluid passages created outside the principal nozzle orifice and defined with the workpiece.

Abstract: An abrading tool for any grinding, lapping, polishing or burnishing purpose (e.g. dental applications) has a rotary holder whose shank can be rotated (e.g. in a chuck connected to a motor) and a plurality of angularly equispaced elongate pieces projecting axially from the holder. The pieces carry abrasive over at least part of their lengths and collectively form a forwardly converging body of revolution about the axis (in a rest position) and the generatrices of this body serve to impact against and abrade the surface to be treated upon rotation of the tool.