Abstract: A sintered electrode for electric discharge machining comprises a continuous phase consisting of a conductive region (3), and a dispersed phase consisting of microscopic polycrystalline diamond (2) dispersed in the continuous phase. The conductive region (3) is cobalt, nickel, cobalt nickel alloy or cemented carbide and imparts conductivity to the electrode (1). The microscopic polycrystalline diamond (2) imparts excellent mechanical strength and thermal diffusion to the electrode (1). The electrode (1) and the workpiece (5) are connected to a power supply (V1) in reverse polarity and a current pulse having ON-time of 60 ? seconds or less and 1 ? second or more and peak of 15 A or less and 1 A or more is supplied to the electrode (1) from the power supply (V1).

Abstract: A press having a machine frame section (10) and a movable section capable of reciprocal movement in a vertical direction relative to the machine frame section, for making products using a pair of dies. The movable section includes a slide (24) to which one of the pair of dies is mounted, and a horizontal guide surface is formed on one of the machine frame section and the movable section. A drive slider (51, 52, 53, 54) has a horizontal sliding surface facing the horizontal guide surface and an inclined sliding surface inclined at a specified angle, and is movably joined to the one of the two sections. A swash plate (51, 52, 53, 54) has an inclined guide surface facing the inclined sliding surface, and is fixed to the other of the two sections. A linear motor (1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b) causes the drive slider to reciplocate along the inclined guide surface of the swash plate through a larger stroke.

Abstract: A press having a machine frame section (10) and a movable section capable of reciprocal movement in a vertical direction relative to the machine frame section, for making products using a pair of dies. The movable section includes a slide (24) to which one of the pair of dies is mounted, and a horizontal guide surface is formed on one of the machine frame section and the movable section. A drive slider (51, 52, 53, 54) has a horizontal sliding surface facing the horizontal guide surface and an inclined sliding surface inclined at a specified angle, and is movably joined to the one of the two sections. A swash plate (51, 52, 53, 54) has an inclined guide surface facing the inclined sliding surface, and is fixed to the other of the two sections. A linear motor (1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b) causes the drive slider to reciplocate along the inclined guide surface of the swash plate through a larger stroke.

Abstract: An electric discharge machine having an electrode mounting device (42) for mounting a tool electrode, a quill (41) movable in the vertical direction and having the tool mounting device attached to a lower end, at least two linear motor movers (43, 44) attached to the quill and disposed symmetrically about the central axis of the quill, at least two linear motor stators (31, 32), each disposed opposite one of the at least two movers, and a balance device (6) for balancing a gravitational force acting on the quill. The balance device has an air cylinder (60) arranged coaxially with the quill so that a balance force having a force vector aligned with the central axis of the quill is generated. The air cylinder is preferably mounted in a hole formed in the center of the quill and extends in a vertical direction.

Abstract: An electric discharge machining apparatus includes a first movable body (40, 42, 50) movable along the Z axis, a ball screw (34), a motor (30) for causing rotation of the ball screw, a nut (35), attached to the first movable body, threadingly engaging the ball screw, a second movable body (10, 13) movable along the Z axis relative to the first movable body, capable of having the tool electrode attached thereto, and a linear motor (71, 72, 73) for moving the second movable body, for machining a workpiece by moving a tool electrode along a Z axis towards the workpiece while causing an electric discharge between the workpiece and the tool electrode. The linear motor includes a stator (73) attached to the first movable body, and a mover (71, 72) attached to the second movable body. The first and second movable bodies include respective electrode attachment units (50, 13).

Abstract: A wire cutting device (3) for cutting a wire electrode (5), used to generate an electric discharge between it and a workpiece (W), comprising a drive gear (12), a follower gear (13) which meshes with the drive gear and is shiftable in its axial direction relative to the drive gear, an adjustable bias mechanism (17) which presses the follower gear against the drive gear in order to accommodate wire electrode of various diameters, materials and conditions, take-up rollers (10a, 10b) which feed spent wire electrode between the drive gear and the follower gear, and a drive mechanism for driving the drive gear such that the peripheral speed of the drive gear is greater than the speed at which the wire electrode is fed out by the wire take up device.

Abstract: An electric discharge machining apparatus comprises a quill 8 movable in the vertical direction, at least one set of linear motor movers attached to the quill, symmetrically about a center axis of the quill, and a single set of linear motor stators facing the set of movers. An electrode mounting device (9) for holding a tool electrode (6) is attached to a lower end of the quill, coaxially with the quill. Preferably, the set of movers includes magnetic plates (12, 14) attached to the quill and a row of permanent magnets (11, 13, 15, 16) arranged on the magnetic plates, and the set of stators includes a yoke (31, 41) and a coil (32, 42) wound around the yoke. The quill has a hole (8a) in its center extending in the vertical direction, and an air cylinder (61) providing counter balance for the load of the quill is preferably disposed in this hole.

Abstract: A wire-cut electric discharge machine in which a current supplying member is in direct contact with a wire electrode, the shape of the current supplying member and the direction of passage of the wire electrode before and after the member being adapted to each other to prevent the formation of narrow gaps of sharp wedge-shaped cross section which could lead to harmful discharge and damage to the wire electrode and possible breakage of the wire electrode. In a preferred embodiment the current supplying member has a thick heel portion and a narrow sole portion and cooling fluid is discharged against the narrow sole portion.

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 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 electrical machining system utilizing a machining liquid consisting at least in a major part of an aqueous solution containing a deionized water and a surface active agent dissolved therein, the latter having a temperature-dependent solubility in the solution and a cloud point, i.e. a temperature below which it remains dissolved therein. The machining liquid is supplied into a machining zone which produces a liquid effluent in which machining products are entrapped. The liquid effluent is fed to a separation zone where it is heated at a temperature above its cloud point to separate out an amount of the surface active agent and to collect that amount substantially in a solid form while forming a liquid output constituted by a remainder of the liquid effluent. The surface active agent is collected by deposition on a carrier material, e.g. iron particles. When iron particles are used, an electromagnet may be employed to decrease the time necessary to recover the surface active agent.