Linear Electromagnetic Pump for the Flow Soldering Equipment

Abstract

In the assembly process of a printed circuit board, automatic flow soldering equipment has been used for more than 50 years. Authors have succeeded in the practical use of a perfectly noncontact linear electromagnetic pump (abbreviated LEP). As a result of the optimization of thrust characteristics, the considerable improvement in the solder performance was confirmed. In this paper, the following subjects are described.
(1) The considerable reduction of the bridge defects between adjacencies electrodes is possible, when following conditions are satisfied, solder rise height y=0.01[m], substrate desorption angle θ=20[deg], square of solder flow velocity v_sy²>0.14.
(2) As a result of evaluating the LEP, it was confirmed that required thrust 15[N] were generated. And then, it became clear that soldering equipment using the LEP surpassed the system using a mechanical pump with regard to soldering performance.