Patent · US Expired

Counterforce spring assembly for printed circuit board test fixtures

US5698990A · kind A · utility

6Cited by
13References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 1996
Grant dateDec 16, 1997
Priority date
Expiry dateJul 10, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R1/073
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A counterforce spring assembly for printed circuit board test fixtures is provided. A number of counterforce spring assemblies are provided in an array between the top plate and probe plate of the test fixture. Each counterforce spring assembly includes a support cup residing in an aperture through the probe plate. A compression spring resides in the support cup and provides spring-biasing of the top plate to the probe plate during the UUT testing cycle. Each counterforce spring assembly includes a circumferential flange to limit downward travel of the top plate toward the probe plate. Each assembly is small enough to fit between probe apertures corresponding to component leads of the UUT. The counterforce spring assemblies can be freely placed underneath the top plate to provide even spring-biasing thereof to prevent bowing and bending of the top plate which often causes errors in the testing of printed circuit boards.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.