Abstract: A solder bridge between leads of a microelectronic circuit is removed by projecting a laser beam onto the solder bridge with sufficient power to cause the solder forming the bridge to melt and to flow onto a wicking tool placed into contact with the solder bridge. The wicking tool is removed during the heating to remove the solder and debridge the leads. Microelectronic leads having a width of the order of 4 mils and a pitch of the order of 8 mils may be debridged easily using the invention.

Abstract: An automated method of brazing to join two metal parts together at a joint with a braze alloy. The two parts are moved to a brazing station and maintained in a fixed position. The two metal parts are heated at the joint at a high heat rate to a predetermined temperature which exceeds the temperature that would melt the braze alloy and less than a temperature that would cause degradation of the metal parts. The temperature of the metal parts in close proximity to the joint is detected and when the first predetermined temperature is reached, the heating rate is reduced to a lower heat rate sufficient to keep the braze alloy in a liquidous state. The braze alloy is introduced to the joint between the two metal parts while they are being heated at the lower heat rate to join the two parts together and then the joined two metal parts are removed from the brazing station.

Abstract: In a method for manufacturing an alloy contact between a wafer-shaped semiconductor substrate (4) and a metal contact wafer (6) a material bond for which the alloy layer reaches only slightly into the interior of the semiconductor substrate (4) is achieved by individually heating the layer arrangement of semiconductor substrate (4) and contact wafer (6) and by means of thermal radiation in a vacuum and by using panel heating elements (13, 17) whose area is larger than the area of the layer arrangement.

Abstract: Apparatus for facilitating the assembly of a structural panel and for preventing the sag thereof comprises an upstanding support structure in the form of laterally spaced rows of longitudinally spaced columns (C) which extend upwardly from a floor support surface (F). Longitudinally extending support beams (B') interconnect the upper ends of the support columns (C), and the structural panel (2) comprising an outer plate (6) and an underlying skelton framework (7) is supported upon the support beams (B'). A radiation heating element truck (4), movable upon laterally spaced rails (8) by means of casters (11), include radiation heating elements (12) mounted upon a support panel (5) whereby the truck (4) is movable between first and second operative positions or stages (A, B).

Abstract: A method of monitoring bonding parameters during a bonding process. The method is based on the object of continuous monitoring of bonding parameters in order to provide adjustment of bonding machines and thereby increase the reliability of the bonded connections. A bonding force is measured by a wire strain gauge attached to a bonding arm and an ultrasound amplitude is measured by a piezo-electric sensor secured to the bonding arm. The method can be used with all bonding machines which work with ultrasound.

Abstract: Method and apparatus for vertical strip clad overlay welding. The method comprises matching the vertical travel of a special welding shoe to an appropriate amount of strip electrode melt-off necessary to maintain a preset molten pool level within a reservoir trough provided by the shoe. The welding shoe comprises a water cooled copper mold for forming the weld bead and a ceramic insert connected to the mold for providing the reservoir trough. Apparatus for correlating the vertical travel speed of the shoe with the strip electrode melt-off is disclosed. Apparatus for applying a plurality of successive weld beads to a vertical vessel wall is also disclosed.

Abstract: A displacement transducer is used to continuously monitor the distance between two fixtures securing parts to be welded. The signal from the displacement transducer is used to stop the welding process when a desired amount of material has been extruded from the weld. The control strategy will automatically take into account part nonuniformities that normally result in poor welds in welding processes that use time as the control variable.

Abstract: An electronic circuit board rework and repair system having a carriage manually movable to successive station positions and having a table thereon movable along mutually orthogonal axes for positioning of a circuit board clamped to the table. At a first station, a circuit board is loaded onto the table, and a microscope can be swung into position for inspection of the loaded board. At a second station, an intended component or circuit board site can be aligned by way of a visual image of the component and site, and the table locked in position. At a third station, the selected component or circuit board site is automatically in alignment with a programmable heater for selected heating of the component contacts and removal of the component by a pickup probe associated with the heater. The system is calibrated such that there is alignment between a visually established position at the second station and that component position under the heater at the third station.

Abstract: Method for reflow soldering respectively desoldering of circuit boards by using infrared radiation from radiator groups in a furnace. The circuit boards are introduced into the furnace on a timed belt or work piece carrier and maintained motionless during the prewarming, soldering respectively desoldering and cooling down phase. For prewarming for a first given time the radiator groups are operated with reduced operating current. For reflow soldering respectively desoldering the operating current of the radiator groups is switched for a second given time to a maaximum given stage and subsequently turned off completely. The soldered respectively desoldered circuit boards are cooled in a laminar air stream from ventilators for drawing off the solder vapors; the ventilators are initially operated with reduced number of rpms until the solder solidifies and then at the maximum number of rpms. Subsequently, the circuit boards are moved out of the furnace.

Abstract: A tool positioning system comprises a discontinuity detection means, such as an eddy current system, for detecting a discontinuity within a workpiece resulting from a joint between a first piece of material relative to a second piece of material, the discontinuity being detected from the back side of the second piece of material. The discontinuity is detected at a plurality of points by translating an eddy current probe over the back side of the second piece of material, the individual points thereafter being utilized to compute line elements that define the joint between the first and second pieces of material in a continuous fashion over the surface of the second piece of material. Thereafter a tool, such as a laser welding tool, is guided along the computed position along the backside of the second piece of material such that the first and second pieces of material are welded together along the joint.

Abstract: In order to hold the longitudinal edges (12, 14) of a can body (10) which are to be butt-welded together contiguous with one another on the way to a welding apparatus (52), the can body (10) is moved past a magnet (40) by means of which the longitudinal edges (12, 14) are magnetized with opposite polarity. The two poles (N.sub.S, S.sub.N) of the magnet (40) each have a supporting surface (42, 44) for a conveyor belt (36) which conveys can bodies (10) one behind the other from a guide member (22) to the welding apparatus (52).

Abstract: The specification sets forth an ultrasonic wire bonding system for bonding wire to an underlying electronic circuit or terminal. The system incorporates a bonding tool connected to a transducer which causes the bonding tool to ultrasonically vibrate and when impressed against a wire lying thereunder, bond said wire to an underlying electronic circuit. The transducer is driven by a generator which generates either a constant current or constant voltage to the transducer while it is bonding. The constant current mode accommodates thick films and stitch bonding which require substantially more force, while the constant voltage mode provides for thin films and ball bonding which requires substantially less ultrasonic force.

Abstract: An automatic ultrasonic wire bonder employs a compliant motion servo (17, 119, 239, 200) on its Z axis drive to maintain a known, constant and steady force applied by the bonding tool (13) to the wire. The tool is resiliently mounted to a carriage (15) that is driven by a force control servo (17, 119, 238, 200). During bonding, the tool is pressed against the wire, and effects of variations in tool tip Z axis position caused by vibration, wire deformation during bonding and other factors of the equipment are minimized by a servo that precisely controls and maintains a fixed position of the carriage relative to the wire to thereby maintain a preselected force between the bonding tool tip and the wire.

Abstract: A multi-mode force control apparatus and circuit for applying a predetermined time dependent force to a workpiece having a variable compliance. The workpiece is supported by an anvil and an actuator is used for applying force to the workpiece. The multi-mode force control apparatus has a position mode sequence that provides a composite position command signal characterizing the predetermined time dependent position of the hammer. A position servo amplifier provides an input control signal to move the hammer from a retracted position to a predetermined first position close to the workpiece. The hammer is then moved slowly into contact with the workpiece. A force reference command signal representing the predetermined time dependent force is increased to a predetermined value. A force signal from a force transducer then rises to a value of voltage representing an ultimate actual force value. A force hold mode timing sequence provides a force hold mode time interval.

Abstract: To match the soldering of an assembled printed-circuit board (13) to its assembly configuration, the circuit board (13) is brought in contact with a soldering wave (21) for a first time along a predetermined path (57, 58), and thereupon the circuit board is rotated about a vertical axis and is brought into contact, preferably with the same soldering save (21), a second time, along predetermined paths from the same direction during its motion along the paths (57, 58). The printed circuit board (13) may be rotated by an angle (.alpha.) depending on the assembly configuration relative to the direction of flow (56) of the soldering wave (21).

Abstract: There is provided a method of controlling a wire bonding apparatus comprising a main arm fluctuated by a drive motor, a sub-arm coupled to the main arm by a coupling force given by a coupling motor, a bonding tool attached to the sub-arm, and ultrasonic wave application means for applying ultrasonic wave to the bonding tool while allowing one end of a wire held by the bonding tool to be in contact with a joining portion of a semiconductor chip to thereby join the wire to the joining portion.

Abstract: A tubing length or workpiece is conveyed to a readying apparatus (A) in which it is cleaned and otherwise readied for inspection. The readied tubing length is conveyed to an inspection and segregating apparatus (B). An ultrasonic array (20) inspects the tubing length, and as a result of the inspection, a switching system (26) places the inspected member on one of: an unrepairable workpiece conveyor (28); an acceptable workpiece conveyor (30); and, a repairable workpiece conveyor (32). The repairable tubing lengths are conveyed to a physical alteration apparatus (C). The physical alteration apparatus removes material, deposits material, hot isostatic pressure consolidates deposited material, and otherwise alters the repairable tubing lengths in such a manner as to bring them into conformity with preselected specifications. The altered tubing lengths are conveyed back to the inspection and segregating apparatus for reinspection.

Abstract: An electronic component tinning apparatus comprising a longitudinal base unit having two longitudinally extending sides connected to a first end and an opposing second end, a top portion connected to and bounded by said sides and ends with an open longitudinal central cavity, and two spaced-apart, parallel longitudinally extending rails mounted on the top portion on opposing sides of said central cavity; a flux tank mounted in said central cavity approximate said first end to hold a liquid flux for flux-coating electronic component leads; a heated pot mounted in said central cavity approximate said second end to hold a hot molten solder bath for tinning the electronic component leads; a powered, wheeled electronic-component transport adapted to ride on said rails to carry electronic components from said first end over the flux tank to the second end over said solder pot and back again; two powered cam means mounted in said transport, rotatable to a high transport position and a low processing position, said c

Abstract: A multi stage heater heats items on a conveyor so that they follow a predetermined temperature profile. The heater is used for printed circuit boards or the like when heated for soldering and avoids thermal gradients that can occur with heating different materials. The heater has a first heater for applying a first quantity of heat to items on the conveyor, a temperature sensing device for determining temperature of items leaving the first heater, a second heater downstream of the first heater and a control system which compares signals from the temperature sensing device with a predetermined temperataure profile to produce a first control output to control the first heater and a second control output to control the second heater so that items passing through the heater follow the predetermined temperature profile.

Abstract: An improved solder reflow system for mass joining with solder electrical and electronic components affixed on a circuit board is provided. The system employs a combination of IR heating, recirculating forced hot air heating, and focused forced hot air heating to achieve solder reflow at throughput speeds and soldering quality not heretofore achievable.

Abstract: A novel and improved monitoring and detecting circuit is provided for an automatic wedge wire bonder. The detecting circuit is initiated at the second wire bond while the bonding tool is pressing the bonding wire on the pad or electrode. If the fine wire is missing under the working face of the bonding tool, the sensing circuit initiates a signal which is detected by control means so as to initiate an interrupt signal stopping the operation of the wire bonder. Sensing of the presence or absence of a wire under the bonding wedge at a bond may take place at a first or a second wire bond. At the second wire bond, the novel sensing and detecting circuit is actuated to determine the amount of longation that takes place in the bonding wire between the bonding wedge and the wire clamps so as to correct the movement of the wire clamps when supplying a tail under the working face of the bonding tool and to ensure that a uniform tail length is supplied unaffected by the elongation of the bonding wire.

Abstract: A desoldering method and apparatus for removal of molten solder from joined parts including a desoldering tool; a vacuum pump connected to the desoldering tool for applying vacuum thereto for removing the solder; a motor for energizing the pump; and circuitry for providing an initial, relatively high, voltage to the motor and for thereafter providing a relatively lower voltage to the motor so that, during the application of the high voltage to the motor, a relatively large pulse of the vacuum is applied to the joined parts to (a) effect removal of substantially all of the molten solder into the desoldering tool and (b) initiate cooldown of the parts and, during the application of the lower voltage to the motor, a relatively lower vacuum is continuously applied to maintain the cooldown of the parts.

Abstract: The invention relates to an apparatus for automatic or remotely operated welding of the cover and/or the bottom of the walls of a container for receiving and storing radioactive fuel elements and wastes in a hot cell by employing the narrow joint welding technique, comprising at least one sensor sensing the course of the weld line between the container wall and the container cover and/or bottom effective to assist at least one three-dimensionally movable welding head controlled by control means utilizing signals supplied by the sensor to guide it along the joint for producing a continuous welding seam consisting of a plurality of super-imposed and offset weld beads or passes, respectively.

Abstract: The invention relates to a manufacturing apparatus which comprises moving means which continuously moves the works that are transferred along a frame chute, and detector means which detects at least a portion of the work that is moved. The moving means is controlled by kind-of-work data and by a work position signal from the detector means, and the work is set to a predetermined position. Hence, even a work of a different kind can be set to an optimum bonding position without the need of exchanging the unit, making it possible to perform the operation fully automatically and to meet general purposes.Further, provision is made of means which moves the frame chute in a direction at right angles with the direction in which the work is moved, so that even that work that has different widths and shapes in the widthwise direction can be placed in position and subjected to the bonding fully automatically.

Abstract: In a method of building an automobile body separate upper and lower body modules (50, 78) are formed, incorporating the roof area and the floor area of the automobile respectively, precision mating locations (62) on the body modules are used first as reference for fitting interior parts and equipment to the respective modules and then for fitting the modules together. An assembly line for carrying out the method has respective sets of stations for forming operations on upper and lower body modules, a mating station (30) at which the two modules are brought together and a joining station (32) where they are, for example, welded. The leading station (20, 22) in each set determines a master body point (64, 82) on a module presented to it, and forms the mating locations (62) on the module with reference to the master body point.

Abstract: Known methods of controlling inertia welding and friction welding processes fail to control metal upset, and so require post machining of the welded components. The invention pre-determines the ideal rates of relative rotation, force applied and metal upset rates for a given material to be welded, enters those rates in a microprocessor memory and then connects the microprocessor to the apparatus on which the weld is to be effected. The microprocessor monitors the actual rates, compares them with the ideal rates and, should differences occur, generates signals from those differences with which to adjust operation of the apparatus.

Abstract: An apparatus and method for fabricating plate web girders of the ind comprising two flanges spaced apart by a web. The apparatus comprises a plurality of welding devices each mounted on respective spaced apart guides to follow a respective portion of a welding path defined by the intersection of the web and a flange and an arrangement to move the girder longitudinally relative to the welding devices at a substantially constant rate. The guides bear against the web adjacent the respective welding paths and against the flange to maintain the welding devices at predetermined distances from the web and flange respectively. The apparatus can also include a member to follow the corrugations of a corrugated web and operate limit switching devices when the crests and troughs of each corrugation are encountered. The limit switches operate a modulating motor which adjusts the welding device to maintain the welding angle between the welding path and welding device substantially constant for each point along the path.

Abstract: The present invention proposes an apparatus or jig for the controlled spot heating of a substrate having soldered components therein and a designated locus to be heated for removal and/or replacement of a component. The apparatus comprises a frame and support means on the frame for holding and positioning the substrate with the locus to be heated along a designated axis of the frame. A rail at one end of the frame parallel to the designated axis holds a heating arm. The heating arm extends along an axis perpendicular to the designated axis and can be positioned along the rail. The heating arm ends in a directing means that is positioned over the designated axis and directs a heating medium, e.g. infra red radiation or a heated gas, onto a locus to be heated. The directing means limits the area of the application of the heating medium to only that area necessary for removal of the component.

Abstract: A method and apparatus for controlling ultrasonic welding and determining whether the weld is of acceptable quality. Power input to ultrasonic welding apparatus is detected and converted to a signal indicative of energy input. When power input exceeds a power threshold level a timer begins to measure elapsed time and energy input begins to be monitored. Welding power is terminated when both elapsed time and energy level have exceeded predetermined values. If either elapsed time or energy level exceeded reject limit values when the weld was made the weld is rejected as being of unacceptable quality.

Abstract: A method and apparatus for preventing a sag of a panel, in which plate to be attached to a skeleton is located on the skeleton supported by a support means, both end parts of the plate are gripped by grasp electrodes of a resistance heating device, current is caused to flow through the plate by the grasp electrodes so as to preheat the plate to a predetermined temperature and to thermally expand it, the plate is welded to the skeleton by a welding machine, and a residual tensile stress is developed in the plate by the thermal shrinkage deformation attendant upon cooling of the plate after the welding. In the case where the plate has a cut-away part, electric conduction members for short-circuiting the cut-away part are interposed in this part so as to form electric conduction paths for the preheating of the plate.

Abstract: An arrangement for soldering aluminum objects which are coated with solder, especially coolers and heat exchangers, comprises at least one oven section and a cooling chamber. A transporting arrangement, especially a carriage, advances the objects to be soldered in succession through the oven section and the cooling chamber. A heating arrangement and a controllable blower are arranged in each of the oven sections provided, being operative for directing heated air against the objects advancing through the respective oven section. A first temperature sensor measures the temperature upstream of the objects as considered in the flow direction of the heated air, while at least one second temperature sensor is arranged at the opposite side of the object from the first sensor and is operative for measuring the temperature of the air that has been discharged from the object after it has intimately contacted and heated the same.

Abstract: Reflow bonding of electronic parts such as large scale integrated circuits onto a printed circuit board, especially on multi-layer printed circuit board, requires that bonding tips press down the part leads with a uniform pressure and in a precise position on the printed circuit board for repeated operations. According to the present invention, the bonding tips providing a protrusion having an acute angle toward part leads, a first driving means for vertical movement of the bonding tips following a predetermined sequence, and a second driving means for opening and closing a gap between two bonding tips are provided in a reflow bonding apparatus.

Abstract: An electromagnetic power drive for a friction welding machine, comprising a magnetic core installed immovably, which carries a power coil connected to a voltage regulator made as a switch and at least one pickup coil connected to an integrator producing voltage proportional to the actual value of the magnetic flux during friction welding, which is connected to a comparison means comprising two comparators, a driving input of one of said comparators receives voltage proportional to the assigned value of the magnetic flux during friction welding, the driving input of the other comparator receives voltage proportional to the other assigned value of the magnetic flux, and a control signal generator having a hysteresis-loop output characteristic, which is connected to the comparators, the output of said generator being the output of the comparison means electrically coupled with the voltage regulator.

Abstract: An ultrasonic generator for providing power to a bonding apparatus having a bonding horn which is brought into contact with respective conductive pads and which carries a wire to be dispensed for interconnection therebetween includes a circuit for applying a voltage at an ultrasonic frequency to the bonding horn to produce a bonding current in the horn, and a monitor for monitoring the bonding current applied to the bonding horn. A circuit is provided for maintaining a zero phase difference between the applied voltage and the monitored current. In addition, a circuit is provided for continuously monitoring and controlling the current which is delivered to the bonding horn to produce a current waveform of a predetermined controllable pattern.

Abstract: A vapor processing system which has a vessel for containing a processing vapor generated by heating electronic fluid contained within the vessel. A selected saturated vapor zone level is devined for work product delivered to the vapor zone by generating a signal representative of the actual temperature at one of a plurality of spaced locations within the vessel, generating a signal representative of the desired temperature at the selected location for a saturated vapor zone having a level selected for the work product being conveyed to the saturated vapor zone, and comparing the signals representative of the actual and desired temperatures at the selected location and for varying the output of the heater to change the actual sensed temperature to the desired temperature so that the actual saturated vapor zone level will conform to the desired saturated vapor zone level.

Abstract: A steel tube working apparatus is composed of a clamping device consisting of a pair of clamps, a pair of projecting plates, means for actuating the clamps and the projecting plates, a pair of guide bars and a main body frame; a base plate having a pair of guide rollers fitting to the guide bars fixedly secured to its opposite ends; and working means connected to the base plate in a movable and rotatable manner. A cutting device, a beveling device, a welding device, etc. are selectively connected to the base plate as the working means.

Abstract: The invention relates to a manufacturing apparatus which comprises moving means which continuously moves the works that are transferred along a frame chute, and detector means which detects at least a portion of the work that is moved. The moving means is controlled by kind-of-work data and by a work position signal from the detector means, and the work is set to a predetermined position. Hence, even a work of a different kind can be set to an optimum bonding position without the need of exchanging the unit, making it possible to perform the operation fully automatically and to meet general purposes.Further, provision is made of means which moves the frame chute in a direction at right angles with the direction in which the work is moved, so that even that work that has different widths and shapes in the widthwise direction can be placed in position and subjected to the bonding fully automatically.

Abstract: A high speed low inertia fine wire clamp is provided for automatic wire bonders of the type which move the bond head and bond head frame relative to the workstation which supports the semiconductor device to be wire bonded. The wire clamp comprises a fixed clamp lever mounted on a bond head link and a movable lever which is pivotally mounted on the fixed wire clamp lever. The wire clamp jaws of the wire clamp levers are spring biased to a normally closed position and are moved relative to each other by a voice coil motor mounted on the wire clamp levers and controlled by a microprocessor to apply predetermined forces on the wire between the wire clamp jaws and to monitor the distance between the jaws.

Abstract: A cold pressure-welding apparatus has a pressure-welding load detector and a displacement detector for detecting the displacement of pressure-welding parts which are mounted on a cold pressure-welding apparatus main body; and an arithmetic operation control circuit which receives output signals from the detectors to detect yield points on a load-displacement curve, calculates an optimum load for optimally performing cold pressure-welding on the basis of a yield load at a second yield point, and outputs to the cold pressure-welding apparatus main body a signal for stopping cold pressure-welding when an actual pressure-welding load reaches the optimum load.

Abstract: For the controlled slowdown of a translatory or rotary machine part to arrest same in a predetermined stop position of an entrained load, the part being driven by an electric motor against a countervailing torque, a trial run is used with a constant motor torque (less than the countervailing torque) to determine a deceleration characteristic under conditions duplicating those of a subsequent production run. The deceleration characteristic is registered in the form of discrete positional values detected at successive instants, these values being stored in a memory for consecutive readout at corresponding instants in a production run and comparison with actual load positions to provide an error signal for the adjustment of the motor torque. A specific embodiment serves to control the final position of a rotary workpiece holder in friction welding.

Abstract: This is a process relating to improvements in the soldering of headers to conventional radiators. Tubular members of the radiator extend through holes in the header. The tubes are initially sealed to the header with a solder having a high temperature melting point T.sub.1. Infrared heat heats the header to a temperature T.sub.2 which is less than T.sub.1 but above a lower temperature T.sub.3 which is the melting temperature of a second solder. Upon the header reaching a selected temperature T.sub.2, a selected amount of the second solder in a molten state is poured in the header to puddle the entire pan area of the header, and allowed to cool to form a very strong soldered connection.

Abstract: A lead wire bonding machine is described for ball bonding the end of a lead wire held in a bonding tool to a die pad of an integrated circuit chip and for wedge bonding a segment of the lead wire spaced from the ball bond to a lead frame finger during successive ball bond wedge bond cycles. The bonding machine includes a variable linear drive such as a solenoid or small linear motor coupled to the bonding head for applying the first bond force to the bonding tool during ball bonding and the second bond force to the bonding tool during wedge bonding. A control circuit coupled to the solenoid or other variable linear drive delivers a first current having a desired profile or amplitude wave envelope for applying the first bond force with a first force profile during ball bonding to die pads and by delivering a second current having a desired profile or amplitude wave form for applying the second bond force with a second force profile during wedge bonding to lead frame fingers.

Abstract: An improved apparatus and method for mass soldering electrical and electronic components populating both the top and bottom surfaces of substrate circuit boards or the like in a single pass is described. The circuit boards pass through a mass soldering station first, and after a timed interval the circuit boards pass through a solder reflow station. The timed interval allows heat transfer through the circuit boards to reach its maximum.

Abstract: An improved lead wire ball bonding machine for bonding wire leads between an integrated circuit chip and the lead frame on which the chip is mounted is provided with a bonding tool position sensor coupled to receive the Z-motion velocity waveform signal to the servo motor which drives the bonding head and bonding tool. This sensor detects the signal level and direction of change or polarity of the Z-motion velocity waveform signal for determining the location of the bonding head and bonding tool. The bonding tool position sensor is coupled and adjusted for generating a first output signal corresponding to a first location of the bonding head and bonding tool during motion downward to the die pad of an integrated circuit chip prior to contact by the bonding tool and lead wire for ball bonding.

Abstract: An automated program controlled discrete soldering system for plated holes of a printed wiring board, having a crucible for holding a discrete amount of solder and operable to travel in a substantial vertical path to a soldering position beneath the board. The solder is metered and deposited in the crucible prior to each application of laser energy to the crucible for melting the solder.

Abstract: An apparatus and a method for remotely refurbishing valve seats are disclosed herein. The apparatus generally comprises a welding assembly having a welding head for depositing a bead of metal around the valve seat, and a positioning assembly detachably mountable onto the valve body for angularly and radially moving the welding head around the valve seat at a selected point along the axis of rotation of the seat. Additionally, the apparatus includes a control means operatively connected to the positioning assembly for controlling the movement of the welding head around the valve seat. In operation, the control means, which may include a microprocessor, first angularly moves the welding head 360.degree. around the circumference of the valve seat, then moves the welding head to a different point along the axis of rotation of the valve seat, and then rotates the welding head 360.degree. around the valve seat again for as many cycles as is necessary to rebuild the valve seat.

Abstract: A control system for use in a condensation heating facility to control the secondary vapor blanket used to prevent loss of primary vapor. The control system includes a pair of secondary vapor sensors which detect a secondary vapor blanket slightly below and alternatively slightly above a design depth. The sensors are connected to control relays which energize a high rate dispensing pump to build the secondary vapor blanket when it is below the low depth and to energize a low rate dispensing pump when the secondary vapor blanket is between the low depth and the high depth. Additional control is arranged to inhibit dispensing of secondary liquid when the secondary vapor blanket is above the high depth or the primary vapor blanket is below its designed depth or finally during a vapor phase heating cycle where the primary and secondary vapor blankets collapse as a function of heating during the cycle.

Abstract: Printed circuit boards 10 having connector terminals 14 and 16 overlaying contact pads 17 and 18 are loaded into fixtures 22 which are conveyor 31 advanced through a pair of solder applying stations 33 and 34 whereat solder is laid and melted at the junctures of the terminals and contact pads. As a fixture approaches a solder applying station, the conveyor is slowed down and a programmed controller 170 is enabled for operation. If a circuit board is sensed by a photodetector 172, a second photodetector is rendered effective to sense elements 176 projecting from a side of the fixture. The sensed elements 176 effectuate the generation of count pulses and output signals to control the movements of solder applying devices 36 to soldering sites where solder feed devices 136 lay discontinuous stripes of solder at the junctures of the contact pads and terminals.

Abstract: A method is provided for joining the ends of steel pipes having male and female ends. The pipe is inserted with the male end into the pipe with the female end and a circular seam is welded, which is disposed at the inside of the female pipe for solidly connecting the pipe with the male end to the pipe with the female end. The male end is preferably provided with a ball section and the female end correspondingly with a ball shaped socket for allowing the pipe to be angled at the connection points. The invention provides the advantage that in automatic welding no large head holes have to be dug out.

Abstract: Apparatus and method for accurately aligning and applying the outside longitudinal weld seam, with the weld seam of a section of large diameter thick gauge steel pipe generally after the inside weld has already been made, including support means for maintaining the pipe section in a stationary position, a plurality of adjustable scanning and tracking assemblies mounted at spaced measured stations along the length of the apparatus, each of which include optical scanning means whereby the scanning and tracking assemblies can be centered with respect to the seam weld of the pipe section at the point of scan, guide means connected to each scanning assembly so that the movement thereof causes said guide means to assume a contour corresponding to the longitudinal weld seam, and a welding machine which follows the path of said guide means to thereby apply the outside weld seam in alignment with the weld seam as the pipe is held stationary and the welding machine travels along the length thereof.