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:
Dec. 02, 1986
Filed:
Mar. 19, 1985
Michael C Boyle, Norton, MA (US);
Pylon Company, Inc., Attleboro Falls, MA (US);
Abstract
Improved spring-stops for a bi-level test fixture of the type that includes an electronic circuit device receiving face moveable between in-circuit and functional testing levels of a probe support plate are disclosed. A spring-loaded plate is provided below the probe support plate, and a plurality of elongated rods that extend between the electronic circuit device receiving face and the spring-loaded plate are provided for transferring the resilient force of the spring-loaded plate to the electronic circuit device receiving face. The transferred resilient force opposes the force exerted on the electronic circuit device receiving face from either operator or automatic testing equipment selectable vacuum levels such that the electronic circuit device receiving face moves to a selected one of the incircuit and functional testing levels. The rods are individually friction-fit for reciprocating motion in a low coefficient of friction and low compressive strength bushing. Each bushing is friction-fit into a corresponding opening provided therefor in the probe support plate. The low compressive strength and low coefficient of friction material of the bushings normalizes reciprocating rod motion induced strain in such a way as to substantially eliminate rod seizing while maintaining an air-tight seal.