Methods and means for use in examining the quality of plated-through holes in circuit boards
US4858479A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1987 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Dec 21, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49124
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A plurality of fragments of printed circuit boards, so-called coupons, each having a row of plated-through holes to be examined and two reference holes, are mounted on positioning pins extending through the reference holes, and are then embedded in a molded block of a curable plastic material to form an independent multi-coupon sample with extending pins ends. A plurality of such samples are mounted in pockets of a sample holder so that their extending pin ends engage with hardened surface portions on the front face of the sample holder. The samples are then contacted by an abrasive element to remove material down to a cross-sectional level corresponding to the common diametrical plane of the plated-through holes. A jig can be used to cut out a coupon with reference holes from a circuit board. Advantageously a sampler holder may be used which has a plurality of abrasion resistant stop screws that can all be simultaneously adjusted by the mutual angular adjustment of a disc portion and a rim portion of the sample holder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.