Abstract:
A method of flow-soldering for mounting an electronic component on a substrate by using lead-free soldering material as soldering material, comprising the steps of installing a heating cover (10) above a preheater (3) and passing the substrate (11) through a clearance between the preheater and the heating cover, wherein a clearance (d1) between the preheater and a soldering tank (5) is set to 20 to 60 mm, and a clearance between a primary jet (7) and a secondary jet (8) is set to 60 mm or less, whereby the efficiency of the flow soldering can be increased in a preheat process or soldering material feeding process.
Abstract:
A spraying flux applying method in a flow soldering process for mounting electronic components on a board (1) by using soldering materials, wherein soldering materials are sufficiently supplied to through holes formed in the board (1). A spraying flux applying method which sprays flux (3) containing solvent and active components toward the board (1) from a nozzle (6) to coat the board (1) with flux (3), the sprayed flux (3) kept in a substantially liquid state being stuck to the board (1). More specifically, the distance between the nozzle (6) for spraying flux (3) toward the board (1) and the board (1) positioned above the nozzle (6) is set to about 30-60 mm.
Abstract:
A bonded structure comprising a board provided with a through hole, a land disposed on the periphery of the through hole, and a lead led out from an electronic part and placed in the through hole. The land comprises an wall face land part on the wall face of the through hole, and front and rear surface land parts on the front and rear surfaces of the board. A fillet for connecting the land with the lead comprises upper and lower fillets parts touching the front and rear surface land parts, respectively, wherein the contour of the upper fillet is smaller than the contour of the lower fillet but larger than the size of the through hole. When a lead-free solder material is employed, occurrence of liftoff can be reduced effectively as compared with a conventional one.
Abstract:
A method of and apparatus for drawing a thick-film circuit on a substrate (2) by bringing a drawing nozzle (1), which has a paste-discharging port at the free end thereof, near the substrate (2) on which a thick-film circuit is to be drawn, and discharging paste from the discharge port onto the substrate (2) while moving the nozzle (1) relatively thereto. If the discharge rate of the paste is controlled in accordance with the relative speed of linear motion of the drawing nozzle (1) to the substrate (2), fluctuations of the thickness and width of the film which occur due to variations in this speed can be prevented, so that a highly accurate thick-film circuit can be formed rapidly.
Abstract:
A method of forming a thick-film circuit which employs a pattern drawing nozzle (102) for discharging a thick-film forming paste (101) that is formed with a paste discharge bore (104) having a substantially large width. The pattern forming nozzle (102) is rotated about the axis of rotation (108) as the thick-film forming paste (101) is discharged from the paste discharge bore (104) such that the longitudinal axis of the paste discharge bore (104) is substantially orthogonal to the advancing direction of the pattern drawing nozzle (102) relative to a substrate (100), whereby the thick-film forming paste (101) is attached to the surface of the substrate (100) in a desired pattern. Also disclosed is an apparatus suitably employed in the above-described method.
Abstract:
Method of mounting an electronic part, which comprises the steps of coating a two-liquid adhesive (12) composed of a main agent and a separate curing accelerator using a dispenser containing a mixture (2) of the main agent and the curing accelerator on the area of a printed circuit board (10) where the part is to be placed, placing the electronic part (13) on the area coated with the adhesive (12), thereafter heating or shining ultra-violet light thereon to cure the adhesive (12), thereby temporarily securing the part (13), and then soldering the part on. This enables the mounting of large-sized electronic parts.