US5196990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal printed circuit board
Assignee: Fuji Electric Co Ltd
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Filing: 1992-03-25
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Granted: 1993-03-23
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Expires: 2012-03-25
Abstract
Abstract A metal printed board having circuit conductors on the surface of an insulating plate layered on a metal plate, wherein grooves formed in the portions of the metal plate which face the circuit conductor. The electronic parts mounted conducts into the metal plate through the solder portions and the insulating plate just thereunder. Accordingly, the presence of the grooves little impairs the thermal conduction. The stray capacitance between the conductor circuit and the metal plate because of the formed grooves, is considerably reduced, so that the signal leakage and noise sneaking are minimized.
Inventors
- 👤 Toshio Kurosaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:12
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/0213; H05K1/0216; H05K1/0201; H05K1/0203; H05K1/0272; H05K2201/00; H05K2201/09; H05K2201/09209; H05K2201/09654; H05K2201/09745; H05K3/00; H05K3/0058; H05K3/0061
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
92 words
In a metal printed circuit board having circuit conductors on a surface of an insulating plate layered on a metal plate having surface portions facing said insulating plate, and electronic parts mounted on said circuit conductors, the improvement comprising grooves formed in said surface portions and underlying said circuit conductors, and lands in said metal plate between said grooves and underlying said electronic parts, said lands being in contact with said insulating plate, whereby said grooves reduce stray capacitance without impairing conduction of heat from said electronic parts to said metal plate.
Claim 2
Dependent Claim
92 words
In a metal printed circuit board having circuit conductors on a surface of an insulating plate layered on a metal plate having surface portions facing said insulating plate, and electronic parts mounted on said circuit conductors, the improvement comprising grooves formed in said surface portions and underlying said circuit conductors, and lands in said metal plate between said grooves and underlying said electronic parts, said lands being in contact with said insulating plate, whereby said grooves reduce stray capacitance without impairing conduction of heat from said electronic parts to said metal plate.
Claim 3
Dependent Claim
46 words
The metal printed circuit board according to claim 1, wherein each of said grooves underlies at least a portion of at least one of said circuit conductors and has substantially the same planar shape as that of said portion of said at least one circuit conductor.
Claim 4
Dependent Claim
46 words
The metal printed circuit board according to claim 1, wherein each of said grooves underlies at least a portion of at least one of said circuit conductors and has a width larger than that of said portion of said at least one of said circuit conductors.
Claim 5
Dependent Claim
39 words
The metal printed circuit board according to claim 1, including soldered interconnections of said circuit conductors and said electronic parts, said soldered interconnections defining part of a path for heat transfer from said electronic parts to said metal plate.
References Cited (Backward Citations)
US4374457A
Cited
US4931905A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-03-22 | 1996-09-21 | 1997-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-22 | 2000-09-21 | 2001-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-22 | 2004-09-21 | 2005-03-23 | $7700.00 | Window Closed / Lapsed |