Lead forming for electronic parts having gull wing type outer leads
US5078186A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1990 |
| Grant date | Jan 7, 1992 |
| Priority date | — |
| Expiry date | Sep 26, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/181
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
For improving both coplanarity and bending accuracy of gull wing type outer leads of electronic parts such as resin molded semiconductor devices, quad flat packages, etc., a lead forming machine is used which incudes a bending die and a stripper which have a pair of faced projections at both sides thereof, and bending punches vertically moving through perforations of the stripper. An electronic part with gull wing type outer leads is disposed between the bending die and the stripper in such a manner that the outer leads extend horizontally from the projections of the bending die. In this case, both sides of outer leads are placed on projections of the bending die without clamping them with the faced projections of the bending die and the stripper. The bending punches are depressed through perforations of the stripper to perform primary lead forming for the outer leads. Thereafter, the bending punches are further depressed to carry out secondary lead forming for the outer leads, while clamping flat portions of outer leads with the faced projections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.