The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 15, 1991
Filed:
May. 16, 1990
Shinichi Makino, Shizuoka, JP;
Naokatsu Kojima, Shizuoka, JP;
Fuji Seiki Machine Works, Ltd., Shizuoka, JP;
Abstract
A pair of solder coating rolls are disposed horizontally adjacent one another for rotation about parallel horizontal axes, and are spaced apart to define a narrow vertically-oriented nip therebetween for accommodating a lead frame therein. Lower parts of the rolls contact a solder bath, and counter rotation of the rolls carries the solder upwardly on the periphery of the rolls to create a small pool of solder at the upper end of the nip. The lead frame is driven vertically upwardly through the nip, which nip has a minimal dimension greater than the lead frame thickness. The lead frame is driven vertically upwardly at a linear speed which is different from, and preferably slower than, the peripheral speed fo the solder coating rolls. This enables preheating of the surface of the lead frame due to its longer exposure to and contact with the hot solder which coats the periphery of the rolls, thereby improving the wetability of the lead frame surface. At the same time, this upward movement of the lead frame through the nip and through the pool of liquid solder permits a solder coating of high quality and uniformity to be applied to the lead frame.