US3602774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for supporting a plurality of printed circuit boards for life test and burn-in
Assignee: AEROTRONIC ASSOCIATES Inc
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Filing: 1970-05-05
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Granted: 1971-08-31
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Expires: 1990-05-05
Abstract
Abstract Method for supporting a plurality of printed circuit boards in superposed relationship for life test and burn-in, such that the power dissipating load resistors of the trays are eliminated from thermal interaction with the devices under test. The trays are vertically staggered with the semiconductors under test being exposed outwardly in ambient air and the power dissipating load resistors being exposed inwardly. The heat from the power dissipating load resistors rises vertically with entrained air within the load. Since the boards are vertically staggered, fresh ambient air is entrained at each level with the result that each board is thermally isolated from the other.
Inventors
- 👤 John Grant
- 👤 Miner R Longley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:35
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/2642; H; H05; H05K; H05K13/00; H05K13/0061; H05K13/0069
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
81 words
Method of supporting a plurality of printed circuit boards using power load circuitry and semiconductors for a life test and burn-in comprising: A. supporting said circuit boards with their sides vertically aligned and in superposed relationship such that the semiconductors being tested are exposed on one side and the power load circuitry is exposed on another side; and B. vertically staggering said boards one above the other such that ambient air may be entrained intermediate the side edges of adjacent boards.
Claim 2
Dependent Claim
81 words
Method of supporting a plurality of printed circuit boards using power load circuitry and semiconductors for a life test and burn-in comprising: A. supporting said circuit boards with their sides vertically aligned and in superposed relationship such that the semiconductors being tested are exposed on one side and the power load circuitry is exposed on another side; and B. vertically staggering said boards one above the other such that ambient air may be entrained intermediate the side edges of adjacent boards.
Claim 3
Dependent Claim
38 words
Method of supporting printed circuit boards as in claim 1, including: C. staggering said boards laterally outwardly, such that the bottom board defines an inner entrainment axis and the edges of upper boards define increasingly outward entrainment axes.
Claim 4
Dependent Claim
81 words
Method of supporting printed circuit boards as in claim 2, including supporting pairs of circuit boards in superposed relationship such that the load circuitry is presented on their inner opposed sides and the semiconductors being tested are exposed outwardly, and vertically staggering the boards one above the other, such that ambient air may be entrained beneath the bottom edges of said boards and flow against the load circuitry on backs of said boards defining a flue and outwardly of the top.
Claim 5
Dependent Claim
42 words
Method of supporting printed circuit boards for a life test and burn-in system as in claim 3, including: D. pulling ambient air, filtering said air at the bottom and then forcing said ambient air upwardly against the staggered backs of said boards.
Claim 6
Dependent Claim
77 words
A hood for supporting a plurality of printed circuit boards in superposed relationship comprising: A. a base; B. pairs of end baffles of increasing horizontal width mounted upon said base and successively one above the other, so as to define a plurality of staggered circuit board supporting brackets; and C. upper and lower slotted guides extending between the ends of said pairs of end baffles and defining channels for engaging the side edges of the circuit boards.
Claim 7
Dependent Claim
77 words
A hood for supporting a plurality of printed circuit boards in superposed relationship comprising: A. a base; B. pairs of end baffles of increasing horizontal width mounted upon said base and successively one above the other, so as to define a plurality of staggered circuit board supporting brackets; and C. upper and lower slotted guides extending between the ends of said pairs of end baffles and defining channels for engaging the side edges of the circuit boards.
Claim 8
Dependent Claim
19 words
A hood as in claim 5, including a filter mounted upon said base beneath said bottom pair of baffles.
Claim 9
Dependent Claim
27 words
A hood as in claim 5, including a blower mounted inwardly of said filter upon said base so as to create a negative pressure within said hood.
Claim 10
Dependent Claim
29 words
A hood as in claim 5, including: D. an electrical connecting bracket at one end of each pair of baffles, extending into a tray mounted positively in said guides.
Claim 11
Dependent Claim
74 words
In a hood as in claim 8 the combination of: A. a printed circuit board tray of the type including a rectangular frame defining an electrical connector support at one end; B. a printed circuit board mounted upon said frame so that its sides extend laterally thereof; and, said tray being mounted in one of said channels so that its electrical connector mates with said electrical connecting bracket in said pair of end baffles.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |