Environmental stress screening apparatus

• US 4,812,750 A
• Filed: 09/28/1987
• Issued: 03/14/1989
• Est. Priority Date: 09/28/1987
• Status: Expired due to Fees

• Current Assignee: Avex Electronics, Inc. (Benchmark Electronics Incorporated)
• Original Assignee: Avex Electronics, Inc. (Benchmark Electronics Incorporated)
• Inventors: Davis, Glen, Parks, William E., Keel, Jerry L., Hines, Thomas M.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): BURNS, WILLIAM
• Application Number:
  US07/101,448
• Time in Patent Office: 533 Days
• Field of Search: 324/158 P, 324/158 F, 324/23 R, 324/158 R, 312/31.01, 312/296, 312/297, 73/430-432, 73/865.6, 174/176 F, 174/176 CT, 174/17.05, 220/240, 220/308, 220/344, 220/378, 292/311, 292/318, 292/240
• US Class Current: 324/750.03
• CPC Class Codes: G01M 99/002 Thermal testing flaw detection G01N25/72
• CPC Class Codes: G01R 31/2817 Environmental-, stress-, or burn-in tests of IC's G01R31/2855; of individual semiconductors G01R31/2642; of other circuits G01R31/2849

Abstract

The disclosed apparatus provides a universal wheeled cart for carrying electronic devices to be stress tested in a sealed environmental chamber in which the temperature is varied between high and low limits while the power to the electronic components is being turned on and off. The cart is configured to substantially fully occupy the insulated heated chamber which is provided with tracks for the wheels of the cart. In addition to a front access door for admitting the cart, the chamber is provided with a rear rectangular aperture through which a novel rectangular bustle mounted on the cart extends. The bustle support a plurality of connectors through which power is supplied to the electronic devices. Complementary power actuated electrical connectors are mounted in fixed relation to the rear aperture, and when actuated, all power connections to the electronic components are made through the bustle and standardized busses on the cart. A unique removable seal on the bustle provides an insulated closure for the rear aperture. The chamber is provided with conventional heating apparatus.

Claims

1. In a system for environmentally stressing electronic components the combination comprising:

a heat insulated temperature controlled chamber having a substantially open front closed by a full width, full height front access door and having a rear wall with an aperture therein, said chamber having a pair of spaced parallel tracks in the floor, said tracks extending from said open front to said rear wall;

a cart for carrying electronic components to be stressed within said chamber, said cart having wheels carried by said tracks, said cart also having a plurality of adjustable shelves for supporting said components;

a bustle having a plurality of electrical connections selectively connectable to said components, said bustle being mounted on the rear of said cart and being aligned with said aperture in said rear wall, and projecting through said aperture when said cart is positioned within said chamber, said bustle having a cross section complementary to said aperture, and dimensioned to provide a gap between the wall surrounding said aperture and said bustle, said bustle having access means enabling access to said connectors from outside the rear wall of said chamber;

a seal mounted on said bustle for sealing the gap between said bustle and the surrounding wall;

a plurality of current carrying busses mounted on said cart, said busses being selectively connectable to components to be stressed and to selective connections in said bustle;

a complimentary connector positioned outside of said chamber in alignment with said bustle, said complimentary connector having connections mating with the connections in said bustle, electrical input currents being supplied to selected ones of said connections of said complementary connector, and electrical output signals being derivable from selected other ones of said connections.

2. The invention as defined in claim 1 wherein said seal comprises a frame removably engaging the periphery of said bustle, first and second spaced pads mounted around the periphery of said frame, said pads filling said gap when said bustle is positioned within said opening, said pads extending from said bustle a distance greater than said gap, whereby said pads are folded when the bustle is positioned in said gap, said bustle being rectangular in cross section and having two side walls and a top wall, said top wall being hinged to provide said access means;

and a vertical guide rail on each side wall, said rectangular frame being provided with complementary tracks engaging said guide rails.

3. A seal for sealing the gap between the rectangular bustle of a cart carrying electronic components to be stress tested within a heat insulated chamber, said bustle supporting a plurality of electrical connectors projecting through an opening in said heat insulated chamber, said seal comprising:

a frame removably engaging the periphery of said bustle, first and second spaced pads mounted around the periphery of said frame, said pads filling said gap when said bustle is positioned within said opening, said pads extending from said bustle a distance greater than said gap, whereby said pads are folded to provide an air lock when the bustle is positioned in said gap;

said bustle having a hinged top access wall and two side walls;

a vertical guide rail on each side wall, and complementary tracks on said rectangular frame said tracks engaging said guide rails.