CH668345A5 - Contacting of electronic components on printed circuit board - using wave soldering of unwired and wired components on surface pretreated with removable solder resist layer - Google Patents
Contacting of electronic components on printed circuit board - using wave soldering of unwired and wired components on surface pretreated with removable solder resist layer Download PDFInfo
- Publication number
- CH668345A5 CH668345A5 CH1301/86A CH130186A CH668345A5 CH 668345 A5 CH668345 A5 CH 668345A5 CH 1301/86 A CH1301/86 A CH 1301/86A CH 130186 A CH130186 A CH 130186A CH 668345 A5 CH668345 A5 CH 668345A5
- Authority
- CH
- Switzerland
- Prior art keywords
- components
- circuit board
- solder
- wired
- contacting
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/341—Surface mounted components
- H05K3/3415—Surface mounted components on both sides of the substrate or combined with lead-in-hole components
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/0094—Filling or covering plated through-holes or blind plated vias, e.g. for masking or for mechanical reinforcement
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/02—Details related to mechanical or acoustic processing, e.g. drilling, punching, cutting, using ultrasound
- H05K2203/0264—Peeling insulating layer, e.g. foil, or separating mask
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/13—Moulding and encapsulation; Deposition techniques; Protective layers
- H05K2203/1377—Protective layers
- H05K2203/1394—Covering open PTHs, e.g. by dry film resist or by metal disc
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/14—Related to the order of processing steps
- H05K2203/1476—Same or similar kind of process performed in phases, e.g. coarse patterning followed by fine patterning
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/15—Position of the PCB during processing
- H05K2203/1572—Processing both sides of a PCB by the same process; Providing a similar arrangement of components on both sides; Making interlayer connections from two sides
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/303—Surface mounted components, e.g. affixing before soldering, aligning means, spacing means
- H05K3/305—Affixing by adhesive
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3447—Lead-in-hole components
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3452—Solder masks
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3457—Solder materials or compositions; Methods of application thereof
- H05K3/3468—Applying molten solder
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Abstract
The component side of the board is treated before attachment of conductorless (surface mount) components with a solder resist layer which covers the holes previously drilled for conventional wired components. Subsequently, the adhesively bonded surface mount components are put through a solder wave for contacting. The solder resist layer is then removed and the circuit board after placement of the wired components on the opposite side is subject to flux treatment and wave soldering on the connection side. This process may be program-controlled to allow for variable solderability of surface mount components. USE/ADVANTAGE - With mixt. of surface mount devices and wired components, both types can be connected in single conventional wave soldering operation without usual cleaning process.
Description
BESCHREIBUNG
Die vorliegende Erfindung betrifft ein Verfahren gemäss dem Oberbegriff des Patentanspruches 1.
Bei der Herstellung von Flachbaugruppen werden anstelle von Anschluss drähte aufweisenden Bauelementen - im folgenden bedrahtete Bauelemente genannt - immer mehr oberflächenmontierbare Bauelemente (SMD: Surface Mounted Device) ¯im folgenden anschlussleiterlose Bauelemente genannt¯ eingesetzt. Damit wird eine rationelle Baugruppenfertigung, eine Verkleinerung der Baugruppen sowie eine bessere Zuverlässigkeit derselben erreicht. Da noch nicht alle gebräuchlichen Bauelemente für die Oberflächenmontage verfügbar sind, wird in nächster Zukunft die gemischte Bestückung mit bedrahteten und mit anschlussleiterlosen Bauelementen dominieren.
Dabei ist es beispielsweise aus der EP-A2-0 104 565 bekannt, die eine Sorte der Bauelemente auf einer Seite und die andere Sorte auf der anderen Seite der Schaltungsplatte anzuordnen und zu kontaktieren.
Wenn die Baugruppen noch kompakter und damit platzsparender aufgebaut werden sollen, entsteht die Notwendigkeit, beide Sorten von Bauelementen auf ein und derselben Seite¯ der Bauteile- oder Bestückungsseite - der beidseitig kaschierten Schaltungsplatte anzuordnen. Bei einer derartigen einseitigen gemischten Bestückung drängt sich zum Kontaktieren der anschlussleiterlosen Bauelemente ein Reflow-Lötverfahren auf, damit bestimmte Stellen und insbesondere die Anschlusslöcher für die anschliessend aufzubringenden und zu kontaktierenden bedrahteten Bauelemente vom Lot freigehalten werden können.
Die bedrahteten Bauelemente hingegen werden üblicherweise mittels Schwallöten kontaktiert. Das Reflow-Löten der anschlussleiterlosen Bauteile bedingt die Verwendung einer Lötpaste, welche Lötpasten in der Regel aggressive Flussmittel enthalten und daher eine Reinigung der Schaltungsplatten nach dem Löten unumgänglich machen.
Davon ausgehend liegt der vorliegenden Erfindung die Aufgabe zugrunde, ein Verfahren zum einfachen Kontaktieren von einseitig auf einer Schaltungsplatte gemischt angeordneten bedrahteten und anschlussleiterlosen Bauelementen anzugeben.
Die Lösung dieser Aufgabe gelingt mit einem Verfahren, wie es im Kennzeichen des Patentanspruches 1 angegeben ist. Vorteil- hafte Weiterbildungen des Verfahrens sind in weiteren Patentansprüchen angegeben.
Ein wesentlicher Vorteil des Verfahrens ist darin zu sehen, dass man für beide Arten von Bauelementen mit einem einzigen Lötverfahren, nämlich dem bekannten Schwallöten auskommt.
Der erwähnte zusätzliche Reinigungsvorgang entfällt somit.
Weitere Vorteile ergeben sich aus der nachfolgenden beispielsweisen Beschreibung des erfindungsgemässen Verfahrens anhand einer Zeichnung.
In der Zeichnung sind die wesentlichen Phasen des Verfahrens schematisch angegeben. Das Verfahren ist in zwei übergeordnete aufeinanderfolgende Schritte A und B unterteilt. Der erste Schritt A beinhaltet das Aufbringen und Kontaktieren der anschlussleiterlosen und der zweite Schritt B das Aufbringen und Kontaktieren der bedrahteten Bauelemente. Da die einzelnen Vorgänge innerhalb dieser beiden Schritte für sich allein bekannt sind, wird hier nur soweit dies zum Verständnis der Erfindung notwendig ist, darauf eingegangen.
Im ersten Schritt wird zunächst eine Schicht von Lötstoplack auf diejenigen Flächenteile der Bestückungsseite der noch unbestückten Schaltungsplatte aufgebracht, die während dem Kontaktieren der anschlussleiterlosen Bauteile vom Lot freigehalten werden müssen. Es sind dies beispielsweise Kontaktflächen für mit der Schaltungsplatte zu verbindende Stecker und evtl. Prüfpunkte. Insbesondere werden dabei aber auch die für die bedrahteten Baulemente vorgesehenen Bohrlöcher abgedeckt, damit kein Lot eindringen und die Löcher verstopfen kann. Dabei wird ein abziehbarer Lötstoplack beispielsweise mittels Siebdruck aufgetragen. Anschliessend wird an den für die anschlussleiterlosen Bauelemente vorgesehenen Stellen ein Klebstoff aufgebracht, der deren nichtleitende Fixierung auf der Schaltungsplatte ermöglieht.
Für das Aufbringen des Klebstoffes gibt es verschiedene Möglichkeiten, so z.B. auch das Siebdruckverfahren. Hierauf werden an den betreffenden Stellen in bekannter Weise die anschlussleiterlosen Bauelemente aufgesetzt. Nach dem Aushärten des Klebers und dem Aufbringen eines Flussmittels wird die Schaltungsplatte mit den anschlussleiterlosen Bauelementen auf der Bestückungsseite durch einen Lotschwall hindurchgeführt. Dabei werden die anschlussleiterlosen Bauelemente mit leitenden Flächen auf der Bestückungsseite der Schaltungsplatte kontaktiert und der erste Verfahrensschritt ist damit abgeschlossen.
Im zweiten Schritt wird zunächst der Lötstoplack entfernt und so die Bohrlöcher für die bedrahteten Bauelemente freigesetzt. Nun können diese Bauelemente auf der gleichen Seite der Schaltungsplatte wie die anschlussleiterlosen Bauelemente in bekannter Weise durch Einführen ihrer Anschlussdrähte in die Bohrlöcher aufgesetzt werden.
Nach dem Aufbringen des Flussmittels auf der der Bestückungsseite gegenüberliegenden Anschlusseite wird die Schaltungsplatte, diesmal mit ihrer Anschlusseite, wiederum über den Lotschwall geführt. So werden die Enden der Anschlüsse der bedrahteten Bauelemente anschlussseitig mit leitenden Flächen der Schaltungsplatte kontaktiert.
Das Verfahren erfordert also sowohl zum Kontaktieren der bedrahteten als auch zum Kontaktieren der anschlussleiterlosen Bauelemente nur ein einziges Lötverfahren, nämlich das seit langem bewährte Schwallöten. Der Einsatz weiterer Lötverfahren und die Anschaffung entsprechender teurer Löteinrichtungen entfällt somit. Setzt man ein Schwallbad mit einer einstell baren Lötwelle ein, ergibt sich im Gegensatz etwa zum Reflow Löten der weitere Vorteil, bestimmte Lötparameter, wie z.B.
den Druck des Lotschwalls, den Abstand der Lötwelle zur Lötebene, die Lötgeschwindigkeit und den Lötwinkel an bestimmten Seiten der durchlaufenden Schaltungsplatte gezielt einstellen zu können. Mit solchen programmgesteuerten Lotschwallanlagen kann auf die unterschiedliche Lötbarkeit von anschlussleiterlosen Bauelementen Einfluss genommen und überall eine gleiche Lötqualität erzielt werden, wodurch die Ausfallrate sinkt.
DESCRIPTION
The present invention relates to a method according to the preamble of patent claim 1.
In the manufacture of printed circuit boards, instead of components with wires - hereinafter referred to as wired components - more and more surface-mountable components (SMD: Surface Mounted Device) are used - hereinafter referred to as connectionless components. This achieves rational assembly production, downsizing of the assemblies and better reliability of them. Since not all common components for surface mounting are available yet, the mixed assembly with wired and leadless components will dominate in the near future.
It is known, for example from EP-A2-0 104 565, to arrange and contact one type of component on one side and the other type on the other side of the circuit board.
If the assemblies are to be made even more compact and thus space-saving, there is a need to arrange both types of components on one and the same side of the component or component side - the circuit board laminated on both sides. With such a one-sided mixed assembly, a reflow soldering process is necessary to contact the connection-less components, so that certain points and in particular the connection holes for the subsequently connected and to be contacted wired components can be kept free of solder.
The wired components, however, are usually contacted using wave soldering. The reflow soldering of the connection-less components requires the use of a solder paste, which solder pastes usually contain aggressive flux and therefore make cleaning the circuit boards after soldering unavoidable.
Proceeding from this, the present invention is based on the object of specifying a method for the simple contacting of wired and connection-less components arranged on one side on a circuit board.
This object is achieved with a method as specified in the characterizing part of patent claim 1. Advantageous further developments of the method are specified in further patent claims.
A major advantage of the method is that you can use both soldering methods for both types of components, namely the known wave soldering.
The mentioned additional cleaning process is therefore eliminated.
Further advantages result from the following exemplary description of the method according to the invention with the aid of a drawing.
The essential phases of the process are shown schematically in the drawing. The method is divided into two superordinate steps A and B. The first step A includes the application and contacting of the connection-less components and the second step B the application and contacting of the wired components. Since the individual processes within these two steps are known on their own, it is only dealt with here insofar as this is necessary for an understanding of the invention.
In the first step, a layer of solder resist is first applied to those parts of the surface of the component side of the circuit board that are not yet equipped that have to be kept free of solder during the contacting of the connection-less components. These are, for example, contact surfaces for plugs to be connected to the circuit board and possibly test points. In particular, however, the drill holes provided for the wired components are also covered so that no solder can penetrate and clog the holes. A peelable solder resist is applied using screen printing, for example. An adhesive is then applied to the locations provided for the connection-less components, which enables them to be fixed in a non-conductive manner on the circuit board.
There are various options for applying the adhesive, e.g. also the screen printing process. The components without connecting leads are placed on the relevant points in a known manner. After the adhesive has hardened and a flux has been applied, the circuit board with the connection-less components on the assembly side is passed through a solder surge. The contactless components are contacted with conductive surfaces on the component side of the circuit board and the first process step is thus completed.
In the second step, the solder resist is first removed and the drill holes for the wired components are released. Now these components can be placed on the same side of the circuit board as the connection-less components in a known manner by inserting their connecting wires into the boreholes.
After the flux has been applied to the connection side opposite the assembly side, the circuit board, this time with its connection side, is again guided over the solder surge. In this way, the ends of the connections of the wired components are contacted on the connection side with conductive surfaces of the circuit board.
The method therefore requires only a single soldering method for contacting both the wired and the contactless components, namely the wave soldering which has been tried and tested for a long time. The use of further soldering processes and the purchase of corresponding expensive soldering devices is therefore eliminated. If you use a wave pool with an adjustable soldering wave, in contrast to reflow soldering, there is the further advantage of certain soldering parameters, e.g.
to be able to adjust the pressure of the solder wave, the distance of the soldering wave to the soldering plane, the soldering speed and the soldering angle on certain sides of the continuous circuit board. With such program-controlled solder surge systems, the different solderability of connectionless components can be influenced and the same soldering quality can be achieved everywhere, which reduces the failure rate.
Claims (3)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1301/86A CH668345A5 (en) | 1986-04-03 | 1986-04-03 | Contacting of electronic components on printed circuit board - using wave soldering of unwired and wired components on surface pretreated with removable solder resist layer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1301/86A CH668345A5 (en) | 1986-04-03 | 1986-04-03 | Contacting of electronic components on printed circuit board - using wave soldering of unwired and wired components on surface pretreated with removable solder resist layer |
Publications (1)
Publication Number | Publication Date |
---|---|
CH668345A5 true CH668345A5 (en) | 1988-12-15 |
Family
ID=4207236
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CH1301/86A CH668345A5 (en) | 1986-04-03 | 1986-04-03 | Contacting of electronic components on printed circuit board - using wave soldering of unwired and wired components on surface pretreated with removable solder resist layer |
Country Status (1)
Country | Link |
---|---|
CH (1) | CH668345A5 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115119416A (en) * | 2022-06-14 | 2022-09-27 | 湖北龙腾电子科技股份有限公司 | Method for solving NPTH hole side line oil thinness in PCB resistance welding process |
-
1986
- 1986-04-03 CH CH1301/86A patent/CH668345A5/en not_active IP Right Cessation
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115119416A (en) * | 2022-06-14 | 2022-09-27 | 湖北龙腾电子科技股份有限公司 | Method for solving NPTH hole side line oil thinness in PCB resistance welding process |
CN115119416B (en) * | 2022-06-14 | 2023-11-21 | 湖北龙腾电子科技股份有限公司 | Method for solving problem of NPTH Kong Bianxian path oil thinning of PCB solder mask process |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PL | Patent ceased |