Probe assembly for measuring conductivity of plated through holes
US4245189A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 1979 |
| Grant date | Jan 13, 1981 |
| Priority date | — |
| Expiry date | Jun 14, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R1/06788
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved probe assembly for measuring the conductivity of a plated through hole in a circuit board. The probe assembly having a longitudinal housing and including at the forward end thereof a segmented current injection electrode, each segment being spring biased forwardly and capable of independent movement longitudinally with respect to the housing between a forward position and rearward position. The segmented current injection electrode injecting current into the through hole substantially 360.degree. of the circular edge formed by the intersection of the walls defining the through hole and the surface of the circuit board. A voltage measurement electrode being a knife-blade electrode is positioned in the interstices between the segments of the current injection electrode. The voltage measurement electrode also being spring biased in a forward direction and capable of longitudinal movement between a forward position and a rearward position. The voltage measurement electrode contacting the circular edge of the through hole at multiple points to insure a good electrical contact for voltage measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.