Abstract: An infrared soldering machine has an inert gas atmosphere to prevent oxidation of the solder. Heaters positioned within the machine housing above a conveyor have through apertures and fans direct inert gas down through the heaters onto the conveyor. The forced convection assists in maintaining uniform temperature across the conveyor. In order to prevent leakage of ambient air into the housing where the fan shafts protrude for connection to electric motors, a gas seal is provided at each fan shaft. The seal extends between two spaced bearings rotatably securing the fan shaft. Each electric motor is mounted away from the heat of the machine and is connected to the respective fan shaft by means of a belt drive. A novel gas curtain, which may be clamped at different angles, improves the gas seal at entry and exit locations of the conveyor.

Abstract: A wave soldering apparatus and process occurs in an atomsphere which substantially excludes oxygen. By providing a gas blanket over the solder, reduction in dross occurs and improved soldering results avoiding the necessity of removing flux residues. Gas diffusers are provided on both sides of a solder wave in an enclosure, the diffusers are placed below the path of the element to be soldered and a further gas diffuser is positioned above the element to be soldered. The gas diffusers supply a calm gas blanket over the solder wave so no turbulent movement of gas occurs within the enclosure.

Abstract: An infrared soldering machine has an inert gas atmosphere to prevent oxidation of the solder. Heaters positioned within the machine housing above a conveyor has through apertures and fans direct inert gas down through the heaters onto the conveyor. The forced convection assists in maintaining uniform temperature across the conveyor. In order to prevent leakage of ambient air into the housing where the fan shafts protrude for connection to electric motors, a gas seal is provided at each fan shaft. The seal extends between two spaced bearings rotatably securing the fan shaft. Each electric motor is mounted away from the heat of the machine and is connected to the respective fan shaft by means of a belt drive.

Abstract: A wave soldering apparatus and process occurs in an atmosphere which substantially excludes oxygen. By providing a pressurized effect on an element to be soldered while passing through a solder wave, fluxless soldering is accomplished avoiding the necessity to remove flux residues. The element is preheated in a shield gas atmosphere substantially excluding oxygen, moved in a predetermined path so that at least a portion of the element passes through the solder wave which is oscillated while the element is in the solder wave and maintained in the shield gas until solder on the element has solidified.

Abstract: Printed circuit boards, assemblies and the like are heated uniformly from edge to edge or to a desired lateral temperature profile while being conveyed through a heating area. The conveying systems reliably conveys circuit boards and the like through the heating area without dropping them. A rail heater is provided to heat rails supporting conveyors having pins to hold circuit boards and the like. A control for the rail heaters controls the temperature of the rails so the circuit boards are positively supported on the conveyors and have a uniform temperature profile or desired temperature profile from edge to edge.

Abstract: Printed circuit boards, assemblies and the like are heated uniformly from edge to edge or to a desired lateral temperature profile while being conveyed through a heating area. The conveying systems reliably conveys circuit boards and the like through the heating area without dropping them. A rail heater is provided to heat rails supporting conveyors having pins to hold circuit boards and the like. A control for the rail heaters controls the temperature of the rails so the circuit boards are positively supported on the conveyors and have a uniform temperature profile or desired temperature profile from edge to edge.

Abstract: A cooling and exhaust unit for an IR reflow soldering machine is arranged to be mounted on the soldering machine after the last heating zone. The unit has fans which direct cold air downwardly on to the conveyor and this cooling air divides into two streams, one moving with the conveyor and one counter to the movement of the conveyor. An exhaust inlet is provided near the front and the rear of the machine, the exhaust inlets being connected through an exhaust chamber to an exhaust outlet. To minimize the amount of hot process air sucked out of the soldering machine into the nearer exhaust inlet an additional cold air inlet is provided, this being located intermediate the rear end of the unit (i.e., the end abutting the soldering machine) and the nearer exhaust inlet.

Abstract: A solder wave nozzle construction allows components to be disassembled for cleaning and removing dross from a solder reservoir. The quick connection joints allow downtime for cleaning a solder wave machine to be greatly reduced. In one embodiment a solder nozzle duct fits over a chimney flow duct and has quick release clips on each side. In another embodiment, a quick release back plate, front plate, exit trough, dross reduction tray and front gate are all easily removable. In a further embodiment a solder nozzle duct fits within a chimney flow duct, and has an adjustable height so it can be positioned for optimum solder wave height.

Abstract: An improved method and apparatus restricts or limits dross formation in a soldering apparatus where liquid solder overflows such as wave soldering and the like. The improvement comprises a solder receiving tray positioned beneath at least a portion of liquid solder falling from an overflow or solder wave to a reservoir and a level control means limits the maximum solder level in the tray above a dynamic solder level in the reservoir, the solder level in the tray being a predetermined distance below the overflow to limit dross formation thus restricting dross recirculation.

Abstract: A foam fluxer for fluxing surface mounted devices on printed wiring boards is suitable for low solids content fluxes. The foam fluxer is for installation in an open tank containing liquid flux positioned under a conveyor path conveying the components. The fluxer comprises an aerator chimney housing with side walls and end walls for placement in and protruding above the open tank, the housing having a top foam outlet for positioning below the conveyor path, at least one vertical internal divider located in the housing below the foam outlet, the divider forming at least two chambers, and a porous aerator tube located in each chamber with connection means for a compressed gas supply to produce foam in each chamber, the foam from each chamber joining above the divider to exit upwards from the foam outlet.

Abstract: Wave soldering process and apparatus for the soldering of elements such as, for example, printed circuit assemblies with surface mounted components and the like which yield improved soldering results by promoting the penetration of solder into narrow spaces between components, the filling of small holes in a board, filling crevices, filling corners adjacent to solder masks and all other areas where solder wetting is difficult to achieve with conventional machines. The process provides the steps of moving an element in a predetermined path, forming a solder wave beneath the path so that at least a portion of the element passes through the solder wave, and producing an oscillation in the solder wave during the passage of the element therethrough.

Abstract: Wave soldering process and apparatus for the soldering of elements such as, for example, printed circuit assemblies with surface mounted components and the like which yield improved soldering results by promoting the penetration of solder into narrow spaces between components, the filling of small holes in a board, filling crevices, filling corners adjacent to solder masks and all other areas where solder wetting is difficult to achieve with conventional machines. The process provides the steps of moving an element in a predetermined path, forming a solder wave beneath the path so that at least a portion of the element passes through the solder wave, and producing an oscillation in the solder wave during the passage of the element therethrough.