Abstract: An electrode quide for electrical discharge machines and welding apparatus. The electrode guide includes at least three sphere-shaped balls in contact with one another and forming an opening therebetween whereat the electrode is received and is guided by the outer surface of each of the balls. The balls are urged toward a frusto-conical shaped bore which forces the balls toward the longitudinal axis of the frusto-conical surface and in contact with one another. The balls can be located within a sphere-shape passageway whereat the balls can rotate with respect to one another in response to angular displacement of the electrode thereby providing a smooth bearing surface for taper cutting. A second set of three sphere-shaped balls can also be provided adjacent the first set of balls in a nesting relation therewith for guiding the electrode through the openings created by both sets of balls.

Abstract: An electrical discharge machine apparatus including a guide assembly for guiding a wire in cutting engagement with a workpiece and having a working end closest to the workpiece. The apparatus incorporates a bore-type or a barrel-type current pickup in sliding engagement with the wire for transferring current to or from the wire. A ring gear is provided on a flush cup coupled to gear teeth on the current pickup in a manner whereby turning of the flush cup causes turning of the pickup for exposing a new surface to the wire. A process is provided for indexing current pickups from the working end of the guide assembly. A process is also provided for removing and replacing guide assembly components from the working end of the guide assembly.

Abstract: An apparatus for transferring electrical current to or from a moving electrically conductive wire includes a rod-shaped electrically conductive member at an angle with a normal straight line of wire travel. The conductive member is received within a bore of a support body. A sleeve is located within the support body bore and between the rod-shaped conductive member and the bore wall. The sleeve includes a channel which is coplanar with the normal straight line of wire travel and communicating with the conductive member outer surface. The channel forms a wire passageway. The moving wire travels through the wire passageway and in contact with the conductive member circular outer surface. The conductive member is rotated about its longitudinal axis for exposing multiple surfaces to the wire and the sleeve is fixed to the support body to prevent movement thereof during such rotation of the conductive member. The sleeve can be made of a non-conductive material.

Abstract: An improved apparatus for placing current on a moving wire electrode traveling between two points and over a conductive member in the form of a rod. The rod is at an acute angle with respect to the normal straight line of wire travel and its circular outer surface is in contact with the moving wire. The improved apparatus provides a mechanism whereby the conductive member is turned about its longitudinal axis thereby exposing a plurality of different contact surfaces to the wire. An index mechanism is provided for stopping the conductive member at a plurality of positions. An indicator mechanism is also provided for indicating to an operator which contact surface is currently being used. The conductive member is loaded onto the support body from the working end.

Abstract: An apparatus for placing current on a moving wire electrode traveling between two points. An electrically conductive member having a circular outer surface and a longitudinal axis is provided at an angle from a straight line between the two points and with its circular outer surface in contact with the moving wire. The moving wire contacts the circular outer surface along a curvilinear path. The conductive member is received within a bore of a holder body. The holder body also includes a wire hole which intersects the bore and communicates therewith through an elongate passage. The moving wire electrode is received through the wire hole and slides over the conductive member surface visible from the wire hole. The contact surface is curvilinear shaped. The conductive member may be turned about its longitudinal axis to expose unworn contact surfaces.

Abstract: A cartridge assembly for a travelling wire electrode electrical discharge machining apparatus includes a cartridge barrel having a first open end and a second open end, and a wire guide mounted in the first open end of the cartridge barrel for guiding the wire electrode. A current pick-up holder is mounted in the second open end of the cartridge barrel and includes an index pin for engagement with a current pick-up. A current pick-up is provided for delivering current to the wire electrode, the current pick-up being mounted in the pick-up holder and including a longitudinal bore for engagement with the wire electrode. The current pick-up includes a first end and a second end, with a tool engagement portion located at the first end of the current pick-up for engagement of a tool to rotate the current pick-up relative to the current pick-up holder. An index pin receiving portion is located at the second end of the current pick-up for receiving the index pin of the current pick-up holder.

Abstract: A wire guiding device for electrical discharge machines (EDM) for easing the threading of wire through the wire guiding assembly. The wire guiding device includes a body wherethrough a longitudinal wire hole is defined having first and second openings. A cavity is located in the body and communicates with the wire hole along a longitudinal communication portion. The cavity is channel-shaped including a planar valley portion and two walls. The planar valley portion intersects the wire hole and forms the longitudinal communication portion and also forms an arcuate groove along the valley portion and in the body. A wear-resistant member is fixed in a bore near one opening of the wire hole and a non-conductive cap is fixed thereover and shields the wear-resistant member and the wire guiding device from electroerosion. A liquid retention chamber is attached to the wire guiding assembly and at least partially surrounds the wire guiding device and has a hole substantially coaxially arranged with the wire hole.

Abstract: A current pickup assembly for placing electrical current on a moving wire electrode in an electrical discharge machine apparatus and having a normal straight line of travel. The current pickup assembly includes a current pickup having a bore therethrough for receiving the wire electrode. The bore longitudinal axis is at an angle with respect to the normal straight line of wire travel and the moving wire electrode contacts the bore contact wall therein. A pivot means is provided for selectively pivoting the carbide pickup longitudinal axis at an angle with respect to the straight line of wire travel. A rotation means rotates the current pickup about the bore longitudinal axis. In the alternative, the current pickup is supported on a gimball means for selectively pivoting the pickup about two mutually perpendicular and intersecting axes of rotation intersecting at a point.

Abstract: A guide assembly for guiding an electrical discharge machine apparatus moving wire electrode through a workpiece. The guide assembly includes first, second, and third guide members, each having a bore for receiving the moving wire electrode and a current pickup is located between the second and third guide members. The first guide member is closest to the workpiece. The first and second guide members are mounted on a guide body at respective first and second openings communicating with one another through a wire passageway through the guide body. The guide body includes a threaded portion and a nut member is used for engaging the threaded portion and attaching the guide body to the support assembly. The nut member includes a housing defining a fluid passageway and an outlet bore for creating a threading fluid stream.

Abstract: An electrical discharge wire cutting machine includes a current pick-up for delivering current pulses from a power supply to an electrode wire. The current pick-up includes a central bore with a continuous curvilinear cross section. The current pick-up is mounted in a holder secured in a first open end of a cartridge barrel. A wire guide for guiding the passage of a wire electrode is mounted in a second open end of the cartridge barrel. A nozzle for directing de-ionized fluid around the wire electrode is secured on the second open end of the cartridge barrel adjacent the wire guide. The current pick-up holder includes a central bore offset from its longitudinal axis in a first direction. A wire pre-guide is mounted adjacent the current pick-up in an enlarged threaded bore of the current pick-up holder. The enlarged threaded bore is offset from the longitudinal axis of the pick-up holder in a second direction.

Abstract: An electrical discharge wire cutting machine (EDWC) includes an apparatus for controlling the flow of electrical energy between an electrically conductive piece part and a wire electrode of the EDWC machine. A pulse type power supply has first and second leads of opposite polarity with the first lead being electrically connected to the piece part and the second lead having first and second portions connected to the wire electrode at two separate, spaced-apart locations. Diodes electrically isolate the first and second portions of the second lead line whereby the first and second portions of the second lead line are electrically independent from one another. Further, first and second independently controllable arrays of capacitors are connected between the first lead line and the first and second portions of the second lead line respectively. The capacitance of these arrays is controllably adjustable to a range of values suitable for the instantaneous cutting conditions.