Abstract: Apparatus and methods for welding asset tracking with heartbeat monitoring are disclosed. In some examples, a welding asset tracking system may comprise an asset tracking network of tags, hubs, and/or gateways retained by welding assets within a welding area. The welding asset tracking system may generate heartbeat signals that certain welding assets may require for normal operation, so as to ensure the welding assets are used in appropriate welding contexts and/or welding areas. In some examples, information obtained from the asset tracking network may be used to determine whether one or more heartbeat signals should be discontinued.

Abstract: A method and apparatus for controlling an electric aircraft. An apparatus comprises a motor, a power source, and a four-quadrant controller. The motor operates in four quadrants of operational space and operates in one of an accelerating state and a regenerative braking state. A total current flows through the motor. The power source is connected to the motor, and when the motor operates in the regenerative braking state, the total current flows through the power source. The power source has a maximum allowable current. The four-quadrant controller is programmed to identify a recharging parameter, brake the motor to initiate the regenerative braking state when the recharging parameter is present, recharge the power source with the total current during the regenerative braking state, and control a duty cycle of the motor such that the total current does not exceed the maximum allowable current during the regenerative braking state.

Abstract: Described herein are laminated packaging materials comprising foamed cellulose, their use in manufacturing packaging containers, for use in packaging of food products.

Abstract: A portable stud welder apparatus is provided for welding a stud onto a work piece. The portable stud welder apparatus includes a housing and an energy storage device. A weld stud gun that is configured to hold a weld stud is electrically connected to the energy storage device for receiving energy from the energy storage device to pass a current through the stud and the work piece to form a weldment. At least one battery of the lithium ion type that is removeably coupled to the housing to establish an electrical connection with said energy storage device and provide energy to the energy storage device.

Abstract: The present disclosure concerns devices and methods for resistance welding sandwich sheets to other components. Many sandwich sheets include a thermoplastic material layer disposed between two metallic cover layers. The sandwich sheet and the other component may be secured relative to one another by a clamping arrangement. A region of the sandwich sheet to be welded may be heated by a preheating current to soften and displace the thermoplastic material layer when the cover layers are pressed together. With respect to the preheating current, a first electrode arrangement may at least temporarily contact an electrically conductive contacting region of the clamping arrangement such that the preheating current can flow via the clamping arrangement. The cover layers may be welded to the other component with a welding current via the first welding electrode of the first electrode arrangement and a second welding electrode of a second electrode arrangement.

Abstract: A tool for positioning a masking plug relative to a surface feature on a component is provided. The tool includes a body extending from a first end to an opposite second end. The second end is configured to couple to an attachment tool. The tool further includes a channel defined in the first end. The channel is sized to receive at least a portion of the masking plug therein such that rotational motion of the tool about a longitudinal axis is transferred to the masking plug. The tool is operable to releasably secure the masking plug to the first end.

Abstract: Present embodiments include systems and methods for stick welding applications. In certain embodiments, simulation stick welding electrode holders may include stick electrode retraction assemblies configured to mechanically retract a simulation stick electrode toward the stick electrode retraction assembly to simulate consumption of the simulation stick electrode during a simulated stick welding process. In addition, in certain embodiments, stick welding electrode holders may include various input and output elements that enable, for example, control inputs to be input via the stick welding electrode holders, and operational statuses to be output via the stick welding electrode holders. Furthermore, in certain embodiments, a welding training system interface may be used to facilitate communication and cooperation of various stick welding electrode holders with a welding training system.

Abstract: Embodiments of energy storage caddies adapted to couple to a welding power supply are provided. The energy storage caddies may include an energy storage device, a charger, control circuitry, and power conversion circuitry. Certain control circuitry may be adapted to control the energy storage device to discharge to provide a direct current (DC) voltage output to the welding power supply when a weld load demand is detected, to monitor a charge level of the energy storage device, and to alert a user to an error when the charge level of the energy storage device falls below a predetermined limit.

Abstract: By superposing a plurality of steel sheets including a high tensile steel sheet and performing pulsation conduction by an inverter DC type spot welding power supply and controlling the conduction time of the current pulses, intervals of the current pulses, that is, conduction idle time, and weld current applied at the current pulses in a variable manner, the optimum weld conditions are obtained. For resistance spot welding of the hot stamped steel sheet, resistance spot welding with a minimum weld current of a second pulsation step higher than the maximum weld current at a first pulsation step is used to suppress the occurrence of outer spatter and inner spatter and secure a broad suitable current range even if using an inverter DC power supply.

Abstract: Techniques are described for version control with selectable file portion synchronization between an IDE and a repository, so that a version control system of this disclosure either synchronizes or ignores different portions of a file during synchronization, in accordance with user selections. In one example, a method includes evaluating content entered into a file. The method further includes detecting a starting delimiter and a stopping delimiter in the file. The method further includes copying a first portion of the file outside the starting delimiter and the stopping delimiter to a repository, and refraining from copying a second portion of the file inside the starting delimiter and the stopping delimiter to the repository.

Abstract: An apparatus includes a main body having an electrode and a contact element. The contact element is directly mechanically and electrically conductively connected to the electrode in order to form an electrical connection between the main body and the contact element. The electrical and mechanical connection between the electrode and the contact element is free of melting regions of the materials of the electrode and of the contact element that are involved in the connection. Furthermore, the connection is realized in a manner free of connection material, for example, in a manner free of solder material.

Abstract: An economical capacitor-type welding device and capacitor-type welding method that have a small power loss, that can be made compact, and that reliably control a charging circuit without being affected by the inductance of a charging path. In an exemplary capacitor-type welding device and an exemplary capacitor-type welding method of the invention, a bypass switching element having a forward-blocking function is connected in parallel to output terminals of a charging circuit, and the bypass switching element is brought into a conduction state to allow a backflow current, which is caused to flow by a magnetic energy stored in the inductance of a primary winding or an inductor included in the charging path, to bypass the charging circuit. A discharge switching element is brought into a conduction state after the bypass switching element enters the non-conduction state and recovers the forward-blocking function.

Abstract: A system and method for repairing a metal substrate includes an electrospark device and an electrode removably supported in the electrode holder. The electrospark device applies a coating of a material when placed into contact with the metal substrate. A cooling device to lowers the temperature of shielding gas flow below an ambient temperature. A conduit is arranged to direct a flow of the shielding gas to the interface of the electrode and the substrate to cool the area of the substrate receiving the coating.

Abstract: The invention relates to electrical discharge milling machines using tool electrodes subject to longitudinal wear. The inventive discharge milling machine is equipped with a numerical controller executing at least one control cycle for compensating the wear considering the following steps: (a) determining the volume Q eroded by each discharge, (b) calculating the distance s travelled by the tool from one effective discharge to the next, (c) calculating the actual eroded linear volume M [m3/m] for at least one effective discharge, M forming a measurement sample from the values Q and s, (d) comparing said sample M with the corresponding set value C to generate an error D=C?M [m3/m], and (e) calculating and transmitting a command by the numerical controller intended to reduce this error D during the following cycle or cycles.

Abstract: A circuit of a full-bridge configuration using four semiconductor switch elements is used as a circuit on the primary side of a transformer in a DC-DC conversion device. With this configuration, it is possible to increase the turn ratio of a primary winding and a secondary winding of the transformer and thus increase a voltage generated in the primary winding, and to decrease a current flowing through the primary winding of the transformer and thus decrease breaking currents of the semiconductor switch elements.

Abstract: A capacitive discharge (CD) welder includes a charging circuit, a capacitor bank, an insulated gate bipolar transistor (IGBT), a pulse transformer and a secondary circuit. The charging circuit takes incoming electricity and charges a capacitor bank. The capacitor bank stores energy. The IGBT electrically connects and disconnects the capacitor bank to the pulse transformer. The pulse transformer reduces voltage from that stored in the capacitor bank to the desired welding voltage. The secondary circuit electrically connected to the pulse transformer provides a welding current corresponding to the output to the material being welded.

Abstract: The capacitive welder includes a charging circuit, a welding transformer, a capacitor, a discharging switching element connected in parallel with a primary winding of the welding transformer and the capacitor that are connected in series, a bypass switching element connected in parallel with the primary winding, welding electrodes connected in parallel with a secondary winding of the welding transformer, and a control circuit for bringing the welding transformer into a reset allowing state by allowing a reset current to flow in the primary winding using the input power introduced through the charging circuit without supplying an ON signal to the bypass switching element, and then supplying the ON signal to the bypass switching element such that the capacitor is charged through the bypass switching element by the input power introduced through the charging circuit.

Abstract: An economical capacitor-type welding device and capacitor-type welding method that have a small power loss, that can be made compact, and that reliably control a charging circuit without being affected by the inductance of a charging path. In an exemplary capacitor-type welding device and an exemplary capacitor-type welding method of the invention, a bypass switching element having a forward-blocking function is connected in parallel to output terminals of a charging circuit, and the bypass switching element is brought into a conduction state to allow a backflow current, which is caused to flow by a magnetic energy stored in the inductance of a primary winding or an inductor included in the charging path, to bypass the charging circuit. A discharge switching element is brought into a conduction state after the bypass switching element enters the non-conduction state and recovers the forward-blocking function.

Abstract: A vaporizer for an exhaust system of an internal combustion engine has a vaporizer tube and a holding sleeve in which the vaporizer tube is inserted. A clamping sleeve sits on the vaporizer tube. The vaporizer tube includes two circumferentially surrounding clamping surfaces which protrude in a radial direction and cooperate with the holding sleeve and the clamping sleeve such that the clamping surfaces are clamped between the holding sleeve and the clamping sleeve by an axial clamping force to be gastight. At least one of the holding sleeve and the clamping sleeve includes a surrounding sealing edge which rests against the respective clamping surface via a line contact and forms an annular sealing seat. The vaporizer further includes a device preventing relative rotation between the holding sleeve and the vaporizer tube. A heater of the vaporizer is attached to the vaporizer tube using a resistance welding method.

Abstract: A two-piece flexplate assembly having a ring gear welded to a central plate using a capacitor discharge welding process. The weld is established between a joining structure defined between the ring gear and the central plate using either an overlap arrangement, a projection arrangement, or a chamfer arrangement.

Abstract: A welding system for welding small precious metal firing tips to spark plug electrodes, such as ground and/or center electrodes. According to one embodiment, the welding system includes a firing tip storage assembly and a firing tip welding assembly, where the firing tip storage assembly uses pressurized gas introduced at the bottom of a part container to float or lift the firing tips so that the firing tip welding assembly can more easily acquire them with a vacuum-driven nozzle that also doubles as a welding electrode. The firing tip welding assembly is mounted to a robotic apparatus that can index or move the firing tip welding assembly between the firing tip storage assembly, a welding station and/or any other suitable positions.

Abstract: The invention relates to a bumper bracket for a motor vehicle body, comprising a first profiled section having a three-dimensional structure and a second component, which spatially closes the first profiled section. The two components have overlapping surfaces used for welding, wherein the welding is carried out by way of impulse capacitor discharge welding.

Abstract: An apparatus and method of uniformly heating, rheologically softening, and thermoplastically farming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool are provided. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to uniformly and rapidly heat a sample or charge of metallic glass alloy to a predetermined “process temperature” between the glass transition temperature of the amorphous material and the equilibrium melting point of the alloy in a time scale of several milliseconds or less. Once the sample is uniformly heated such that the entire sample block has a sufficiently low process viscosity it may be shaped into high quality amorphous bulk articles via any number of techniques including, for example, injection molding, dynamic forging, stamp forging, and blow molding in a time frame of less than 1 second.

Abstract: A process for cohesive bonding between a metal surface and a nonmetallic substrate is provided. The non-metallic substrate may comprise a plurality of microfilaments and/or nanofilaments dispersed into and below the surface of the substrate. The application of pressure and laterally-oriented high frequency and low amplitude vibration may allow for diffusion bonding between the metal surface and material of the nanofilaments. Another method includes discharging energy from a bank of capacitors to melt adjoining surfaces of the metal surface and nonmetallic substrate. Additionally, a cohesive bonding method may further comprise converting electrical oscillations of ultrasonic frequency into ultrasonic vibrations which are transmitted to the metal body and/or substrate for fusing the two materials together.

Abstract: For manufacturing a gas generator (1), a tubular body (10) having an opening (14) in a circumferential wall (12) and a housing part (16) having an attachment end (26) are provided. The geometry of a proximate rim (20) of the opening (14) and that of the attachment end (26) are coordinated such that a first contact region encircling the opening (14) and a second contact region on the attachment end (26), which is circumferentially closed, are formed. The housing part (16) is placed onto the tubular body (10) such that the first contact region is in contact with the second contact region. Then the body (10) and the housing part (16) are joined to each other by capacitor discharge welding.

Abstract: A weld circuit for use in a welder is provided. The weld circuit comprises a charge section, a capacitor section, and a weld section. The charge section includes a first plurality of solid state switches, e.g., silicon controlled rectifiers (charge SCRs), the capacitor section includes a weld capacitor, and the weld section includes a second plurality of solid state switches, e.g., silicon controlled rectifiers (weld SCRs). The charge SCRs form a bridge between the lines in the charge circuit. One weld SCR is coupled to a first weld terminal and the other weld SCR is coupled to a second weld terminal. The charge and weld SCRs isolate the charge section, the capacitor section, and the weld section from each other. The weld circuit is coupleable to a safety circuit that comprises a resistor, a microcontroller, and optical isolators. When the optical isolators are enabled, the microcontroller monitors a current flowing through the resistor.

Abstract: A micro-welder, by which a superfine wire such as a lead wire can be welded on a desired position of a parent material with a minimum welding area, including: a power source having a capacitor-charging device for generating a predetermined voltage and a voltage controller for adjusting the level of voltage output from the capacitor-charging device; a charge-storing member connected in parallel to the power source for storing the voltage output from the capacitor-charging device; a switching member connected in parallel to the charge-storing means for conducting the voltage output from the capacitor-charging device; a switch driving member for turning-on the switching member; and a welding circuit connected in serial to the switching member.

Abstract: A micro-welder, by which a superfine wire such as a lead wire can be welded on a desired position of a parent material with a minimum welding area, including: a power source having a capacitor-charging device for generating a predetermined voltage and a voltage controller for adjusting the level of voltage output from the capacitor-charging device; a charge-storing member connected in parallel to the power source for storing the voltage output from the capacitor-charging device; a switching member connected in parallel to the charge-storing means for conducting the voltage output from the capacitor-charging device; a switch driving member for turning-on the switching member; and a welding circuit connected in serial to the switching member.

Abstract: A resistance welding apparatus characterized by very low output impedance, and providing a substantially constant voltage source to low impedance (e.g., resistances on the order of 1-100 micro-ohms) materials-to-be-joined. The welding apparatus includes one or more primary and secondary winding pairs disposed about a high permeability core with the secondary coil(s) positioned between the primary coil(s) and the core. In a preferred form, the secondary coil(s) are capable of delivering more than 75,000 amperes of welding current. The welding apparatus is lighter, more cost efficient, and more energy efficient than conventional systems.

Abstract: A method of manufacturing male bimetal slippers includes the steps of forming a stem having opposite first and second ends; rigidly affixing a ball on the first end of the stem to form a male slipper body; and capacitance discharge welding a wear pad to the second end of the stem. To manufacture female bimetal slippers the method includes forming a slipper body of a first material, the body having opposite first and second ends, the first end having a ball socket formed therein; and capacitance discharge welding a wear pad of a second material to the second end of the body.

Abstract: Disclosed is a resistance welding power supply apparatus which comprises a large-capacitance capacitor for storing resistance welding energy in the form of electric charges, a charging circuit for charging the capacitor to a predetermined voltage, four switching elements or means electrically connected between the capacitor and a pair of welding electrodes, and a control unit for allowing selective switching operations of the switching elements during a weld time to provide a control of welding current. Diodes are connected in parallel with the switching elements, respectively, with current polarities opposite thereto. The control unit terminates a switching pause period for polarity switching in a very brief time and initiates a switching control in the next current-supplying mode in the middle of fall of the welding current.

Abstract: A resistance welding power supply apparatus comprises a large-capacitance capacitor for storing resistance welding energy, a capacitor charging circuit, a switching element electrically connected between the capacitor and one electrode of a pair of welding electrodes, and a control unit for the switching element. If the welding current is less than a set current value at a point of time on the leading edge of a clock, then the control unit holds a control pulse for the switching element active or high from that point of time till the time when the welding current exceeds the set current value without being affected by the cycle of the clock. If the welding current exceeds the set current value at a point of time on the leading edge of the clock, then the control unit holds the control pulse inactive or low till a point of time on the leading edge of the next clock.

Abstract: The invention concerns a method for producing a flame support for a gas burner, which consists in producing disjointed metal fibres (10) in an alloy comprising iron, chromium and aluminium; assembling the fibres together under pressure; bringing the fibre mat to a temperature sufficient to ensure a close bonding between the fibres. The invention is characterised in that it consists in feeding said metal alloy to an overflowing tank (3), to produce the fibres by cooling in contact with a mobile wheel (7); then in arranging in a moulding matrix the resulting disjointed fibres (10) and compressing them to form an agglomerated mat; then in connecting the mat to electrodes and a capacitor, thereby bringing the fibres (10), at their points of contact, to a temperature not less than their melting point, to produce fibres closely welded together, under high voltage.

Abstract: A capacitor has a positive electrode that is electrically connected to a welding electrode on one hand by way of a switching transistor for the supply of welding current and has a negative electrode that is electrically connected to a welding electrode on the other. The capacitor is charged by a charging circuit. A charging control unit accepts as a charging voltage monitor signal an output signal of a comparator and provides a control of the charging circuit so as to allow a capacitor voltage fed to one input terminal of the comparator to conform to a set voltage fed by a main control unit. This power supply apparatus includes two designation modes, i.e., a direct designation mode in which the user directly designates a desired capacitor voltage, and an indirect designation mode in which the user designates a standard current value as a provisional standard for a welding current so that the apparatus can automatically set a capacitor voltage corresponding to the standard current value designated.

Abstract: The invention relates to a welding apparatus (1), particularly a resistance welding apparatus, comprising a control device (2), a charging device (10), at least one energy store (22 to 24), a switching device (33 to 35) and a consumer (51), the energy store (22 to 24) being incorporated in parallel with the charging device (10) and the said energy store being connected, via the switching device (33 to 35) associated therewith and a transfer device (31) subsequent thereto, to the consumer (51), particularly a welding torch (52) with a non-melting electrode (53) and a workpiece (54). A plurality of energy stores (22 to 24) are disposed each with an associated switching device (33 to 35), and the switching devices (33 to 35) of the energy stores (22 to 24) are triggered between two charging cycles by the control device (2) for directly successive emission of at least a portion of the energy stored in one of the energy stores (22 to 24) to the consumer (51).

Abstract: A method of assembly of impeller (12) and turbine (14) shells (116) for torque converters (10). Vanes (116) are capacitance discharge welded with a high energy pulse into the shells (112).

Abstract: The circuit has a transformer on whose primary side there is a storage capacitor which can be charged and discharged in a controlled manner and to whose secondary circuit a load is connected. Two ancillary capacitors of the same capacitance are connected in a circuit between the storage capacitor and the transformer, and the storage capacitor's capacitance is a multiple of the capacitance of each ancillary capacitor. Each ancillary capacitor is connected via a charge-control element to the storage capacitor and via a discharge-control element to the transformer, and forms a parallel resonant circuit with the inductance of its discharge circuit. Control means are connected to the charge- and discharge-control elements in order to alternately and cyclically charge and discharge the ancillary capacitors in a controlled manner. By these means, sequences of partial pulses are generated which, for each sequence, collectively form a current pulse.

Abstract: A method is provided to replace a damaged pin in a module for an integrated circuit assembly without damaging the circuit device or chip mounted in a circuitized substrate. This method comprises brazing a new pin to the base of the old pin by capacitive discharge brazing with a ribbon of compatible metal foil, requiring no flux, and is effected by firing the charge by completing a circuit which includes a pin attachment tool, the ribbon and the power supply, but in which circuit the chip is bypassed. The arc is struck and the new pin is brazed to the old without generating sufficient heat to damage the chip, and without conducting any current through the chip. The attachment tool is uniquely adapted to clamp the new pin and locate the pin precisely over the base of the old pin.

Abstract: Voltage stored in a capacitor bank (12) of a capacitor discharge welding apparatus is modified in accordance with the magnitude of output energy actually delivered to the weld. After empirically determining capacitor bank voltage and output energy emloyed in the making of an acceptable weld, energy delivered to subsequent welds is monitored (50,56). An efficiency factor based upon stored voltage and delivered energy of the prior weld is determined. Based upon this efficiency factor and the output energy delivered during the prior weld, a new value of capacitor voltage is calculated for use in a subsequent weld. Regulation of the voltage on the capacitor bank (12) is determined by a feedback circuit which senses capacitor bank voltage, compares it to a set point, and shuts down a boost charging circuit when capacitor voltage has reached a predetermined amount.

Abstract: A welding apparatus is disclosed to include an electrically insulating casing, first and second welding electrodes, and one or more welding transformer cores having toroidal cores, multi-turn primary windings and a single-turn secondary winding. The cores include a grain-oriented silicon steel material coiled with an insulator. The primary windings have turns axially wound about the cores. The secondary windings include at least two conductive arm sections which are connected to the electrodes and a wound section including conductive wire cable which electrically connects the two arm sections. One of the arm sections can provide the frame member to support the transformer. The apparatus is suitable for spot or linear welding.

Abstract: A coated sheet material is provided for wrapping, packaging or shipping food articles that are to be heated in a microwave oven. The sheet is formed from a paper or paperboard backing which is thermally and dimensionally stable when exposed to microwave energy. On at least one side is provided a smooth calendered surface or the sheet material is treated by processing as with a filler coating to fill the voids between the paper fibers and to thereby present a smooth surface. A microwave interactive layer is applied to the smoothed surface from a fluid or vapor state. The interactive coating can comprise carbon, a semiconductive metal coating or other microwave interactive material.

Abstract: A coating sheet material is provided for wrapping, packaging or shipping food articles that are to be heated in a microwave oven. The sheet is formed from a paper or paperboard backing which is thermally and dimensionally stable when exposed to microwave energy. On at least one surface is provided a smooth supercalendared surface or the sheet is treated by processing as with a filler coating to fill the voids between the paper fibers and to thereby present a smooth surface. A microwave interactive layer is applied to the smoothed surface from a fluid or vapor state. The interactive coating can comprise carbon, a semiconductive metal coating or other microwave interactive material.

Abstract: A capacitor type welding power unit incorporates a constant-current charging control circuit which serves to control a charging current being supplied to a capacitor so as to be substantially constant during the charging. By such a control circuit, which typically performs a thyristor firing control, the charging voltage of the capacitor is made to follow a reference signal, which is preferably set to change linearly with time, and it reaches a preset target value in a predetermined time regardless of fluctuations in the supply voltage. Furthermore, such a control circuit enables the capacitor to be directly connected to the output terminals of a rectifier circuit with no charging resistor being provided so as to reduce resistance heating and so as to lower power consumption in charging the capacitor.

Abstract: One or more optical fibers are attached to an optical component element or supporting substrate by coating the peripheral surface of the optical fiber with a metallic layer and then positioning the metallic layer in electrical contact with a metal surface of the object along an interface. An electrical current pulse or pulses is applied through the interface sufficient to cause local melting or near melting and welding at the interface.

Abstract: A precision electric welding device is used for welding dental crowns and bridges in the mouth. The dental elements to be welded comprise dentally suitable metals, especially titanium and titanium alloys. The device comprises a welding gun and a base unit provided with a direct current voltage source and a storage device for storing welding sequences. Each welding sequence defines the energy requirements for successive pulses in a particular welding operation. The base unit generates a series of controlled voltage potentials for each operation, and the welding gun is responsive thereto for performing the welding operations. The portable welding system is of the capacity-discharge, contact-resistance type, and performs welding with high-precision endo-oral metals by generating controlled sequences of electrical energy pulses (1) selected from a permanent storage library, or (2) manually controlled from a local console, or (3) externally controlled from an external computer.

Abstract: In a spot welder in which the electric charge stored in an electrolytic capacitor (1a) is discharged through a welding circuit 3 to perform a welding operation, in order to prevent the lowering of the welding performance due to the inversion in polarity of the voltage of the electrolytic capacitor (1a), its main circuit includes another electrolytic capacitor (1b) which is connected in series to a DC source (5) and shunted by a resistor (7) and which is substantially equal in capacitance to the aforementioned electrolytic capacitor (1a), and after the electrolytic capacitor (1a) only is charged, a switch (2) is turned on so that the charge current of the electrolytic capacitor (1a) is discharged to charge the electrolytic capacitor (1b), whereby charging the electrolytic capacitors (1a) and (1b) in opposite directions is prevented.

Abstract: A resistance-type welder employing a three phase, pulsed power supply and a pair of opposed electrodes which a workpiece may be clamped under pressure, includes a microcomputer based control system for allowing precise selection and control of welding sequences such as the duration during which the workpiece is clamped, the duration during which current is supplied to the electrodes and the duration during which the workpiece remains clamped between the electrodes after current flow is terminated. A plurality of switchable input devices allows data corresponding to a plurality of process variables to be input to a random access memory. A central processor enabled by a manually operable control switch produces control signals for operating a control and firing circuit in accordance with programmed instructions and the data stored in the random access memory in order to control each step in a welding cycle for precise time periods.

Abstract: A precision electric welding device is used for welding dental crowns and bridges in the mouth, the dental elements to be welded being made up of dentally suitable metals, especially of titanium and titanium alloys. The device comprises, in combination, an electronic welding base unit supplied with direct current voltage source and provided with a storage device containing a plurality of welding sequences, each welding sequence defining the energy requirements for successive pulses in a particular welding operation. The base unit generates a series of controlled voltage potentials for each operation, and an interdental precision electric welding gun is responsive to said series of controlled voltage potentials for performing the welding operations.

Abstract: A power supply for a pulse type electrical resistance welder includes an A.C. source of electrical power, a firing circuit for delivering spikes of current to a pair of welding electrodes and a precharging circuit for precharging the firing circuit with a quantity of electrical energy sufficient to produce satisfactory welds in the first cycle or first few cycles of power. The precharging circuit is controlled by control circuit which includes a thumb wheel switch for presetting the voltage to which the firing circuit is to be precharged. A relay circuit automatically disconnects the precharging circuit from the firing circuit before the latter discharges its energy to the welding electrodes. A safety circuit is provided for automatically discharging the firing circuit in the event of a power failure.

Abstract: Apparatus and method are described for rapid ball formation at the end of lead wire retained in the capillary wire holding tool of a ball bonding machine. A circuit is coupled between the cover gas shroud and lead wire for establishing controlled electrical discharge between the end of the bonding wire and the shroud, for melting and forming a ball. The circuit includes a DC power supply for delivering a positive polarity to the shroud and negative polarity to the lead wire for drawing a discharge of electrons from the end of the lead wire to the shroud. A capacitor is coupled in series with the DC power supply for receiving the electrical discharge. An impedance is also coupled in series for limiting the electrical discharge current. Charging of the capacitor limits and shapes the electrical arc discharge to a controlled pulse profile of short duration for rapid ball formation. An electronic gate is also used to control pulse duration.