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Patent US4332342A successfully refreshed from Google Patents.
US4332342A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of soldering components to a thick-film substrate
Assignee: US Philips Corp
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Filing: 1981-03-23
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Granted: 1982-06-01
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Expires: 2001-03-23
Abstract
Abstract A method of and a device for soldering components on thick-film substrates according to the reflow method. Successively, the substrates are preheated, followed by heating to the soldering temperature, after which they are cooled. A wave of molten metal of a given temperature is used for preheating, heating and cooling of the substrates.
Inventors
- 👤 Henricus C. A. van Der Put
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:26
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/08; B23K1/085; H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3494; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K1/09; H05K1/092; H05K2203/00; H05K2203/07; H05K2203/0756; H05K2203/0776; H05K2203/11; H05K2203/111; H05K2203/15; H05K2203/1581
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
146 words
In the method of soldering components to a thick film substrate comprising: (1) heating an assembly of said substrate with said components locally provided with a layer of solder between said components and said substrate in a preheating phase to a temperature below the melting point of said solder; (2) heating said assembly to a temperature sufficiently high to cause the solder to melt and flow during a soldering phase and (3) subjecting said assembly to a temperature during a cooling phase to a temperature below the melting point of said solder; the improvement wherein through each of said phases the substrate bearing the layer of solder and the components positioned therein is contacted with a heated molten metal heat transfer medium and during the cooling phase the substrate is cooled at a rate sufficiently effective to cool said substrate below 150° C. within 2 seconds.
Claim 2
Dependent Claim
146 words
In the method of soldering components to a thick film substrate comprising: (1) heating an assembly of said substrate with said components locally provided with a layer of solder between said components and said substrate in a preheating phase to a temperature below the melting point of said solder; (2) heating said assembly to a temperature sufficiently high to cause the solder to melt and flow during a soldering phase and (3) subjecting said assembly to a temperature during a cooling phase to a temperature below the melting point of said solder; the improvement wherein through each of said phases the substrate bearing the layer of solder and the components positioned therein is contacted with a heated molten metal heat transfer medium and during the cooling phase the substrate is cooled at a rate sufficiently effective to cool said substrate below 150° C. within 2 seconds.
Claim 3
Dependent Claim
26 words
The method of claim 1 characterized in that the substrate is successively guided along and pressed against a number of waves of the heated molten metal.
Claim 4
Dependent Claim
21 words
The method of claim 1 or 2 characterized in that, during the preheating phase, the substrate is preheated in two steps.
Claim 5
Dependent Claim
128 words
The method of claim 3 wherein the substrate consists of aluminum oxide and the solder paste consists of a lead tin alloy having a melting point of 183° C., characterized in that in the preheating phase, the soldering phase and the cooling phase the molten metal heat transfer medium is in the form of a molten lead-tin-bismuth alloy of a melting point from 95° to 100° C., the temperature of the heating phase is 180°±5° C., the temperature of the soldering phase is 250°±3° C. and the temperature of the cooling phase is 110°±5° C., respectively, the substrate is in contact with the molten lead-tin-bismuth alloy for 8 seconds during the preheating phase, for 2 seconds during the soldering phase, and for 2 seconds during the cooling phase.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-31 | 1985-11-30 | 1986-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-31 | 1989-11-30 | 1990-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-31 | 1993-11-30 | 1994-06-01 | $7700.00 | Window Closed / Lapsed |