US3882596A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of flux-free soldering of aluminum-containing workpieces in a controlled atmosphere
Assignee: Vereinigte Aluminium Werke AG
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Filing: 1974-09-05
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Granted: 1975-05-13
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Expires: 1994-09-05
Abstract
Abstract A furnace for flux-free soldering of aluminum-containing workpieces in a controlled atmosphere has a furnace chamber through which workpieces to be soldered are made to travel. The furnace chamber itself is a gas-tight metallic muffle which is thermally insulated from the outer part of the furnace and has an inlet for the workpieces and an outlet for them. A first lock chamber is interposed between the furnace chamber and the inlet, and a second lock chamber is interposed between the outlet and the furnace chamber. Arrangements are provided for admitting vacuum and protective gas into the lock chambers, and protective gas into the muffle and a heating arrangement is provided for heating the controlled atmosphere in the muffle.
Inventors
- 👤 Keinz Kendziora
- 👤 Johannes Nenner
- 👤 Heinz Schoer
- 👤 Werner Schultze
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:16
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/008; B23K35/00; B23K35/22; B23K35/38; B23K35/383; F; F27; F27B; F27B5/00; F27B5/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
95 words
In a method of flux-free soldering of aluminum-containing workpieces in a controlled atmosphere, the steps of admitting the workpieces to be soldered into a preheating chamber; preheating said workpieces to at most 500*C in said preheating chamber; admitting the thus preheated workpieces into a lock chamber containing a protective gas; admitting said workpieces from said lock chamber into a gas-tight muffle containing a controlled atmosphere, and effecting soldering in said controlled atmosphere; and discharging the soldered workpiece from said muffle through an additional lock chamber containing a protective gas, into a cooling zone or chamber.
Claim 2
Dependent Claim
95 words
In a method of flux-free soldering of aluminum-containing workpieces in a controlled atmosphere, the steps of admitting the workpieces to be soldered into a preheating chamber; preheating said workpieces to at most 500*C in said preheating chamber; admitting the thus preheated workpieces into a lock chamber containing a protective gas; admitting said workpieces from said lock chamber into a gas-tight muffle containing a controlled atmosphere, and effecting soldering in said controlled atmosphere; and discharging the soldered workpiece from said muffle through an additional lock chamber containing a protective gas, into a cooling zone or chamber.
Claim 3
Dependent Claim
20 words
In a method according to claim 1, wherein said workpieces are heated in said gas-tight muffle to the soldering temperature.
Claim 4
Dependent Claim
16 words
In a method according to claim 1, wherein said controlled atmosphere is a protective gas atmosphere.
Claim 5
Dependent Claim
20 words
In a method according to claim 3, wherein said protective gas atmosphere in said muffle has a low oxygen content.
Claim 6
Dependent Claim
28 words
In a method according to claim 4, wherein said protective gas atmosphere having a low oxygen content is heated to the soldering temperature and circulated within said muffle.
Claim 7
Dependent Claim
28 words
In a method according to claim 1, wherein the soldered workpiece is cooled in said cooling zone or chamber by directing an air blast against said soldered workpiece.
Claim 8
Dependent Claim
14 words
In a method according to claim 1 wherein said controlled atmosphere consists of nitrogen.
Claim 9
Dependent Claim
19 words
In a method according to claim 7 wherein said nitrogen has a dew point of lower than -60* C.
Claim 10
Dependent Claim
21 words
In a method according to claim 1 wherein the workpieces are preheated in said lock chamber to at least 100* C.
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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |