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EP0381435A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Method and apparatus for washing circuit boards

Assignee: Nokia Oyj
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Filing: 1990-01-30
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Granted: —
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Expires: 2010-01-30
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Abstract

Abstract The present invention concerns a method for washing off flux residues subsequent to soldering from a circuit board or equivalent component. The circuit board washing procedures of prior art have either been detrimental to the environment or poor in their washing result. These problems have in the present invention been solved by including at least one step in the procedure in which steam is sprayed on the circuit board or equivalent. The steam spraying step is advantageously combined with preceding water washing and rinsing steps. A circuit board or equivalent component rinsed with hot steam is recovered in a cleaner condition than before, and moreover, entirely dry.

Inventors

  • 👤 Aulis Tuominen

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 05:24
CPC Classifications
H; H05; H05K; H05K13/00; H05K13/0061; B; B08; B08B; B08B3/00; B08B3/02; H05K3/00; H05K3/22; H05K3/26; B08B2230/00; B08B2230/01; H05K2203/00; H05K2203/07; H05K2203/0779; H05K2203/0786; H05K2203/08; H05K2203/088

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 37 words
A method of washing off flux residues after solde­ring from a circuit board or equivalent component, characte­rized in that it comprises at least one step in which steam is sprayed on the circuit board or equivalent component.
Claim 2
Independent Claim 37 words
A method of washing off flux residues after solde­ring from a circuit board or equivalent component, characte­rized in that it comprises at least one step in which steam is sprayed on the circuit board or equivalent component.
Claim 3
Dependent Claim 43 words
A method according to claim 1, characterized in that said steam jet step is accomplished with water vapour pre­vailing under such pressure and at such temperature that it removes, in addition to the impurities, all moisture from the circuit board or equivalent component.
Claim 4
Dependent Claim 72 words
A method according to claim 1 or 2, characterized in that the steam jet step is accomplished by vaporizing water, by directing the produced steam into nozzles positioned in a chamber, where it from several directions is sprayed against the circuit board or equivalent component, and by maintaining the steam chamber under small overpressure for letting steam out of the chamber directly into the air or through a condenser into a sewer.
Claim 5
Independent Claim 89 words
A method according to any one of claims 1,2 or 3, characterized in that it comprises, in addition to the steam jet step, at least one of the following steps: - the circuit board or equivalent component is washed with water, advantageously in a closed space in the presence of a detergent; - the circuit board or equivalent component is rinsed by spraying water thereon, this advantageously being heated, which steps precede said steam jet step; and finally - the circuit board or equivalent component is dried and cooled.
Claim 6
Independent Claim 38 words
A method according to any one of the preceding claims, characterized in that it is an in-line-process in which the circuit board or equivalent is conveyed through zones accomplishing the above-mentioned steps, said zones being arranged in series.
Claim 7
Dependent Claim 38 words
Apparatus for washing off flux residues subsequent to the soldering from a circuit board or an equivalent com­ponent, characterized in that it comprises at least a zone (6,7,8) for spraying steam towards the circuit board or equivalent component.
Claim 8
Dependent Claim 38 words
Apparatus for washing off flux residues subsequent to the soldering from a circuit board or an equivalent com­ponent, characterized in that it comprises at least a zone (6,7,8) for spraying steam towards the circuit board or equivalent component.
Claim 9
Dependent Claim 100 words
Apparatus according to claim 6, characterized in that the steam jet zone consists of a steam producing means (7), supply members for supplying steam into its jet ejecting nozzles, jet ejecting nozzles directed towards the circuit board from different sides, and of a steam chamber (6) therearound, provided with holes for introducing a circuit board or equivalent component into the steam chamber (6) and out of it, and of a discharge aperture (8) on the wall of the steam chamber for discharging the steam out of the chamber, and possibly of a condenser for condensing the steam exiting the chamber.
Claim 10
Dependent Claim 89 words
Apparatus according to claim 6 or 7, characterized in that the apparatus also comprises - a closed washing space (3) with requisite transport and washing members, and with a supply and an outlet for washing water; - a rinsing zone (4,5) with rinsing liquid supply, spraying members and outlets (5), whereby the washing space (3) and the rinsing zone (4,5) are placed before the steam spraying zone (6,7,8); and subsequent to the steam spraying zone (6,7,8) - a drying and cooling zone (9) with drying air supply and outlet.
Claim 11
Dependent Claim 78 words
Apparatus according to any one of the preceding claims 6-8, characterized in that said closed washing space (3), said rinsing zone (4,5), said steam spraying zone (6,7,8), and said drying and cooling zone (9) have been disposed in succession and surrounded with compact outer walls but separated with inner walls from each other, and that through the zones a conveyance of the circuit board or equivalent component has been arranged with including loading (2) and discharging (11) projections.

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