Abstract:
Method of laser welding which comprises at least two steps : a first step wherein the laser (10) is operated for some time T1 at low intensity in order to create a melt (31) in one part (12) with little or no evaporation of matter, thereby reducing product contamination, and a further step wherein the laser is operated for a shorter time T2 at high intensity in order to push said melt (31) towards a further part (13), whereby large gaps between said parts can be bridged, yet further reducing product contamination thanks to the low laser energy needed to proceed with the further step. Optionally, a third step is performed during a third period of time (T3) in which the weld is post-heated.
Abstract:
A bath apparatus 12 reserves a liquid 13 as a heating medium and includes an input partition bath 31, a first intermediate partition bath 32, a heat partition bath 33, a second intermediate partition bath 34 and a removing partition bath 35 that are divided by gates 21 through 24 and sequentially arranged in a direction in which a printed board assembly where components are loaded onto a printed board moves. The temperatures of liquids 13-31 and 13-32 in the input partition bath 31 and the first partition bath 32 are a preheating temperature. The temperature of a liquid 13-33 in the heat partition bath 33 is a soldering temperature. The gate 21 is gradually opened while the printed board assembly 11 is located in the first intermediate partition bath 32 and before the printed board assembly 11 is conveyed into the heat partition bath 33. The liquid in the heat partition bath 33 is mixed with the liquid in the first intermediate partition bath 32, and thus the temperature of the first intermediate partition bath 32 is gradually increased to the soldering temperature. The temperature of the printed board assembly 11 is gradually increased from the preheating temperature to the soldering temperature.
Abstract:
A soldering apparatus for soldering a printed wiring board, including a solder vessel (1) for containing a molten solder, a nozzle (8) disposed in the vessel and having a first opening (37) and a second opening (21), and an electromagnetic pump (12) secured in the vessel and including a tubular member (20a) defining a solder flow path therein and having an inlet (34) and an outlet (13) connected to the second opening (21) of the nozzle. The pump has cores (19,18) and coils (42) disposed at a position below the surface level of the molten solder and arranged to generate a moving magnetic field in the path when the coils are electrically energized, so that the molten solder is fed from the inlet to the outlet and is projected from the first opening of the nozzle to form a solder wave.
Abstract:
L'invention concerne un dispositif de brasage à la vague pour cartes électroniques câblées, à partir d'un réservoir destiné à contenir de la soudure liquide, d'une colonne montante (1) dirigée vers le haut, dont l'extrémité inférieure communique avec le réservoir et dont l'extrémité supérieure s'ouvre sur une plaque perforée (2) munie de plusieurs orifices de débordement (9) de soudure liquide disposés transversalement par rapport au trajet de la carte électronique afin que la soudure liquide qui en déborde et qui est destinée à entrer en contact avec la carte électronique, puisse former une vague turbulente et qui s'écrase au passage d'une carte électronique. Dans le but de permettre à moindre coût une variation du temps de contact entre la face inférieure de la carte à circuits imprimés et l'onde de soudure, il est proposé de prévoir des moyens (5, 6) pour faire varier l'angle de la surface de la plaque perforée (2) par rapport à l'horizontale.
Abstract:
There is provided a soldering flux for circuit board, which is designed to be employed on an occasion of soldering electronic parts on a circuit board, the soldering flux being free from any organic solvent which may become a cause for contaminating air atmosphere and being capable of providing an excellent insulating property. This soldering flux comprises; a rosin-based modified resin having an acid value of not less than 100, a nondissociative activator formed of a nondissociative halogenide, and an aqueous solvent containing a volatile basic agent. There is also provided a circuit board having a flux film formed from such a soldering flux.
Abstract:
An apparatus and method for connecting together first and second printed circuit boards 10/20 (PCBs), wherein one or both of the PCBs is a flex circuit. The method includes overlapping the two PCBs such that their respective matching circuit trace arrays 12/22 face each other and are separated by a small predetermined distance K, and then introducing molten solder 30 proximate an overlapping PCB edge 18, such as by wave soldering, so as to urge capillation of the molten solder between the two PCBs, thereby forming solder joints operatively connecting together the two circuit trace arrays.
Abstract:
An apparatus for compressing viscous material (100) through openings (48) in a stencil (46) is disclosed. The apparatus has a compression head cap which provides a contained environment to direct and to aid the flow of pressurised viscous material through the openings (48) in the stencil (46). The apparatus further includes a selectively expandable diaphragm (218, 318, 418, 518) which selectively and expandably allows the viscous material (100) to be dispensed into the compression head cap.
Abstract:
There are provided a method of soldering a lead-free solder which lowers a melting point of the lead-free solder and prevents deterioration of a joining strength at a portion joined by the lead-free solder, and a joined object soldered with the use of the soldering method. The lead-free solder as an alloy of tin with no lead contained is melted, and ultrasonic vibration is acted at least either to the join object to be joined by the lead-free solder or to the lead-free solder when the molten lead-free solder is solidified. Therefore crystals of contained components in the lead-free solder are made fine and the contained components are prevented from being segregated at a joining interface of the joined object, so that the joining strength at the joining interface can be increased.