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GB2418881A - Wave soldering apparatus - Google Patents

Wave soldering apparatus Download PDF

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Publication number
GB2418881A
GB2418881A GB0422002A GB0422002A GB2418881A GB 2418881 A GB2418881 A GB 2418881A GB 0422002 A GB0422002 A GB 0422002A GB 0422002 A GB0422002 A GB 0422002A GB 2418881 A GB2418881 A GB 2418881A
Authority
GB
United Kingdom
Prior art keywords
solder
inert gas
molten solder
nozzle
soldering apparatus
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB0422002A
Other versions
GB2418881B (en
GB0422002D0 (en
Inventor
Willemen Lambertus Christiaan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vitronics Soltec BV
Original Assignee
Vitronics Soltec BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vitronics Soltec BV filed Critical Vitronics Soltec BV
Publication of GB0422002D0 publication Critical patent/GB0422002D0/en
Publication of GB2418881A publication Critical patent/GB2418881A/en
Application granted granted Critical
Publication of GB2418881B publication Critical patent/GB2418881B/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/08—Soldering by means of dipping in molten solder
    • B23K1/085—Wave soldering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K3/00—Tools, devices, or special appurtenances for soldering, e.g. brazing, or unsoldering, not specially adapted for particular methods
    • B23K3/06—Solder feeding devices; Solder melting pans
    • B23K3/0646—Solder baths
    • B23K3/0653—Solder baths with wave generating means, e.g. nozzles, jets, fountains
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2101/00—Articles made by soldering, welding or cutting
    • B23K2101/36—Electric or electronic devices
    • B23K2101/42—Printed circuits
    • 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
    • H05K2203/04—Soldering or other types of metallurgic bonding
    • H05K2203/044—Solder dip coating, i.e. coating printed conductors, e.g. pads by dipping in molten solder or by wave soldering
    • 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
    • H05K2203/08—Treatments involving gases
    • H05K2203/081—Blowing of gas, e.g. for cooling or for providing heat during solder reflowing
    • 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
    • H05K2203/08—Treatments involving gases
    • H05K2203/086—Using an inert gas
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Molten Solder (AREA)
  • Electric Connection Of Electric Components To Printed Circuits (AREA)

Abstract

A wave soldering apparatus includes a blowing device 12 for blowing inert gas 18 towards the solder wave 7 so as to ensure that it overflows out of the nozzle 4 in the correct direction, i.e. in a direction opposite to the direction of travel of the printed circuit board 6 being soldered. The wave soldering apparatus also comprises a solder bath 1, and a pump 3 for pumping solder 2 through the nozzle 4. Preferably one or more sides of the nozzle 4 is/are made of a wettable material 5, with the other side(s) being made of a non-wettable material, further ensuring that the solder wave 7 flows along the wettable material 5 in the correct direction. A wettable guiding strip (14, figure 4) may be mounted next to the nozzle 4 to perform the same function. The supply of inert gas 18 is preferably able to be switched on and off quickly, and a heating element (11, figure 2) is preferably used to heat the inert gas 18 to prevent forced cooling of the solder wave 7.

Description

1 241 8881 Apparatus for selective soldering.
This invention relates to an apparatus for soldering on printed circuit boards of through hole components, containing leads.
More and more surface mount components are used for printed circuit assemblies, characterized by small dimensions and soldered by a reflow soldering process.
Many of the circuit assemblies contain however components that are not suitable for reflow soldering. This concerns in general components like connectors and electrolytic capacitors, which have through hole leads that need to be mounted onto printed circuit boards and soldered on the other side of the print. The solder has to be applied at the bottom, the solder side, of the printed circuit board.
A soldering apparatus is known which contains: - a solder pot to store and heat the molten solder; - a transport device to move the assembly to be soldered over the nozzle and carry off the soldered assembly; - at least one vertical mounted nozzle in the solder pot; through which the molten solder flows and overflows over the nozzle plate back into the described solder pot; - a pump device to supply the molten solder at the bottom of the nozzle; and a transport device for at least bring together the bottom side of the assembly to be soldered and the top side of the nozzle.
In this manner the nozzle forms a small soldering apparatus. Herewith it is possible to solder by moving the assembly just over the solder wave. The solder will penetrate into the barrels along the leads of the through hole components at the bottom side of the printed circuit assembly.
It is already known that a soldering apparatus with a nozzle has one disadvantage, that is the solder does not always flow in the proper direction, the opposite direction of the dragged printed assembly.
The result of the total forces leads to unstable flow behaviour of the molten solder. Resulting in bridging between one or more leads. This includes also, that during the design of the printed circuit assembly space must be created for the flowing solder; on those areas no components are allowed.
It is already known that the shape of the vertical nozzle forces the molten solder to flow to one direction, but this does not always gives the required result.
The present innovation has for its aim 'o produce a soldering apparatus with which the molten solder always flows in a defined direction, that is the opposite direction of the transported printed circuit assembly.
By experiences it is known, that stable flows of the molten solder in one define direction prevents bridging and damaging of the surrounded surface mount devices.
In the first presented invention an inert gas is blown towards the solder, in such way that the solder is forced to flow in the proper direction.
According to a further development of the apparatus, the gas supply can be switched on and off quickly to optimise the blowing without effecting the soldering process.
To achieve a proper solder temperature it is required to adjust the gas temperature.
According to a further development of the apparatus, the invention proposes a vertical nozzle including a wettable flow plate at the overflow side of the molten solder, where as the other sides of the nozzle are made out of non-wettable materials.
The non-wettable part of the nozzle will reject solder and solder will flow along the wettable part that attracts the molten solder.
In a particular embodiment a metal strip is mounted along the vertical nozzle. This strip is made out of wettable material and will attract molten solder. Instead of a strip, it is also possible to have another shaped wettable material, like a rod.
DE19807696 describes an apparatus for soldering supplying a gas surround a vertical mounted nozzle through which molten solder flows. In this device the heated gas is used to have an inert atmosphere in the soldering area.
The solder is overflowing in all directions of the nozzle, which requires more free space on the painted assembly to prevent damaging of surface mount components.
The examples, which follow, explain the invention: Figure 1 is a schematic overview according the innovation; Figure 2 is a schematic overview of a device for the supply of an inert gas including a device that offers the ability to fast switch on and off the supply of gas; Figure 3 is a detailed view of the vertical nozzle with wettable overflow plate; Figure 4 a detailed view of a vertical nozzle with a wettable metal strip.
Figure 1 shows a solder pot (1) that is filled with molten solder (7). For the melting and keeping the solder liquidus the heating elements are used that are known in today's technology, which are not drawn in figure (1).
In the solder pot (1) is a vertical nozzle (4) is mounted. By means of a pump (3) the solder is pumped from the solder pot (1) through the vertical nozzle (4).
The molten solder (7) will flow out of the vertical nozzle back into the solder pot (1). To make a solder connection the printed circuit assembly (6) is moved by means of a transport device (8) of which only the grippers are drawn, to a short distance of the vertical nozzle (4).
Next the printed circuit assembly (6) is dragged over the vertical nozzle (4), which makes the overflowing molten solder (7) connecting the leads (9) of the components (10) to the bottom side of the printed circuit assembly (6).
To make the molten solder (7) flow over the slope surface (5) of the vertical nozzle (4) a inert gas, for example nitrogen, is blown out of a blowing device (12) in the direction of the overflowing opening (19) of the vertical nozzle (4).
The inert gas (18) flows via the blowing device (12) against the flowing molten solder (7) into the direction of the slope surface (5).
The solder will select the direction of the lowest resistance and flow over the slope surface (5) back into the solder pot (1).
Figure 2 illustrates a device to quick switch on and off of the supplied inert gas (18). This may be necessary to prevent the molten solder (7) to be blown through the holes of the printed circuit assembly (6). The device contains a heating element (11) through which the inert gas (18) is blown. Heating of the inert gas (18) is necessary to prevent a forced cooling of the liquidus solder.
A distribution valve (15) is open, through which the supplied inert gas (18) is blown into the free space.
During the soldering this distribution valve (15) will be closed. This will blow the inert gas (18) through the blowing device (12) against the molten solder (7). A cylinder (17) makes the distribution valve (15) quickly open and close allowing the inert gas (18) fast changing between blowing against the molten solder (7) and into the free space. This prevents the molten solder to be blown on top of the printed circuit assembly (6).
Figure 3 shows another design that forces the solder to flow into the proper direction. This innovation uses wettable and non-wettable materials. The characteristic of a wettable material is that it attracts the molten solder (7) where as the non-wettable material the molten solder (7) rejects. The solder that flows out of the vertical nozzle (4) is attracted by the slope surface (5), made out of wettable material. The other part of the vertical nozzle (4) is made out of a non-wettable material, like stainless steel, and will reject the solder.
Figure 4 shows another design of a vertical nozzle (4) made out of nonwettable materials with a guiding strip (14). The guiding strip (14) is made out of wettable material and will attract the flowing molten solder (7).

Claims (5)

  1. CLAIMS: 1. A soldering apparatus containing: - a solder pot (1) for
    storage and heating of the molten solder (7); - a transport device (8) to drag and carry off the circuit assembly over the solder pot!1); - at least one vertical nozzle (4) mounted in the solder pot (1); through which the molten solder (7) is pumped overflowing through the nozzle opening (19) back into the described solder pot (1); - a pump (3) to supply molten solder (7)through the bottom of the vertical nozzle (4); and a transport device (8) to bring together the bottom side of the printed circuit assembly (6) and tr.e top side of the vertical nozzle (4), characterized in that an inert gas (18) is blown through the blowing device (12) that makes the molten solder (7) overflowing through the nozzle opening (19) in the correct direction.
  2. 2. A soldering apparatus as claimed in Claim 1, characterized that one or more sides of the vertical nozzle (4) is made of a wettable material (5) and the others of a non-wettable material (4), which will make the solder flow along the wettable material (5) in the correct direction.
  3. 3. A soldering apparatus as claimed in Claim 1 an/or 2, characterized that next to the vertical mounted nozzle (4) a wettable guiding strip (14) is mounted, which makes the molten solder (7) flow through the nozzle opening (19) along the wettable guiding strip (14).
  4. 4. A soldering apparatus as claimed in Claim 1, characterized that the supply of the inert gas (18) can be switched on and off quickly. The apparatus contains a heating element (11) through which an inert gas (18) is blown.
    An open distribution valve (15) makes the supplied inert gas (18) through the exhaust tube (16) flow into the free space. During soldering the distribution valve (15) will be closed. This makes the inert gas (18) flow through the blowing device (12) against the molten solder (7).
    A cylinder (17) makes the distribution valve (15) open and close fast, which makes it possible to switch fast between blowing the inert gas (18) against the molten solder (7) or into the free space.
  5. 5. A soldering apparatus as claimed in Claim 4, I' characterized in that the temperature of the inert gas . (18), that flows out of the blowing device (12), is controlled to prevent forced cooling of the molten solder (7) by guiding through the heating element (11) and ë I: heated to the desired temperature before blown through the blowing device (12).
    5. A soldering apparatus as claimed in Claim 1, characterized that the temperature of the inert gas (18), that flows out of the blowing device (12), is controlled to prevent forced cooling of the molten solder (7).
    Therefore the inert gas (18) is guided through a heating element (11) and heated to the desired temperature before blown through the blowing device (12).
    Amendments to the claims have been filed as follows 1.A soldering apparatus containing: - a solder pot (1) for storage and heating of molten solder (7); - a transport device (8) to drag and carry off a printed circuit assembly over the solder pot (1); - at least one vertical nozzle (4) mounted in the solder pot (1); through which the molten solder (7) is pumped overflowing through a nozzle opening (19) back into the described solder pot (1); - a pump (3) to supply molten solder (7)through a bottom of the vertical nozzle (4); the transport device (8) bringing together a bottom side of the printed circuit assembly (6) and the nozzle opening of the vertical nozzle (4), characterized in that an inert gas (18) is blown through a blowing device (12)
    -
    ^'. so that the molten solder (7) overflows through the ^-, nozzle opening (19) in the correct direction. .
    2.A soldering apparatus as claimed in Claim 1, .
    characterized in that one or more sides of the vertical nozzle (4) is made of a wettable material (5) and the others of a non-wettable material (4), which will make the solder flow along the wettable material (5) in the correct direction.
    3.A soldering apparatus as claimed in Claim 1 and/or 2, characterized in that next to the vertical nozzle (4) a wettable guiding strip (14) is mounted, which makes the molten solder (7) flow through the nozzle opening (19) along the wettable guiding strip (14).
    4. A soldering apparatus as claimed in Claim 1, containing - a supply of the inert gas (18) that can be switched on and off quickly; - a heating element (11) through which the inert gas (18) is blown; - an open distribution valve (15) making the supplied inert gas (18) flow through an exhaust tube (16) into a free space, while during soldering the distribution valve (15) will be closed resulting in the inert gas (18) flowing through the blowing device (12) against the molten solder (7); - a cylinder (17) making the distribution valve (15) open and close fast, which makes it possible to switch fast between blowing the inert gas (18) against the molten solder (7) or into the free space. .
GB0422002A 2003-10-07 2004-10-05 Apparatus for selective soldering Expired - Lifetime GB2418881B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL1024476A NL1024476C2 (en) 2003-10-07 2003-10-07 Device for selective soldering of components on a print plate with classical connecting wires includes means to blow oxygen on solder to make sure its flow in correct direction to prevent formation of bridges between connecting wires

Publications (3)

Publication Number Publication Date
GB0422002D0 GB0422002D0 (en) 2004-11-03
GB2418881A true GB2418881A (en) 2006-04-12
GB2418881B GB2418881B (en) 2008-04-09

Family

ID=33432540

Family Applications (2)

Application Number Title Priority Date Filing Date
GB0422002A Expired - Lifetime GB2418881B (en) 2003-10-07 2004-10-05 Apparatus for selective soldering
GBGB0422186.7A Pending GB0422186D0 (en) 2003-10-07 2004-10-07 Apparatus for selective soldering

Family Applications After (1)

Application Number Title Priority Date Filing Date
GBGB0422186.7A Pending GB0422186D0 (en) 2003-10-07 2004-10-07 Apparatus for selective soldering

Country Status (2)

Country Link
GB (2) GB2418881B (en)
NL (1) NL1024476C2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3113587A1 (en) * 2014-02-28 2017-01-04 Fuji Machine Mfg. Co., Ltd. Viscous fluid coating device
US20170209949A1 (en) * 2014-07-29 2017-07-27 Illinois Tool Works Inc. Soldering module
US20220009017A1 (en) * 2020-07-08 2022-01-13 Illinois Tool Works Inc. Soldering nozzle, system and use

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105345208B (en) * 2015-12-18 2019-05-31 东莞市合易自动化科技有限公司 Tin spraying device with blowing structure

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1110892A (en) * 1965-04-28 1968-04-24 British Aircraft Corp Ltd Improvements relating to wave soldering
GB1352746A (en) * 1970-11-02 1974-05-08 Electrovert Mfg Co Method and apparatus for soldering and tinning
GB2008013A (en) * 1977-08-31 1979-05-31 Frys Metals Ltd Improvements in wave soldering machines
GB2360237A (en) * 2000-03-16 2001-09-19 Evenoak Ltd Nozzle for soldering apparatus

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3092059A (en) * 1958-01-20 1963-06-04 Motorola Inc Assembly apparatus
US4824010A (en) * 1980-12-26 1989-04-25 Matsushita Electric Industrial Co., Ltd. Process and apparatus for soldering printed circuit boards
US4934309A (en) * 1988-04-15 1990-06-19 International Business Machines Corporation Solder deposition system
US5292055A (en) * 1991-12-06 1994-03-08 Electrovert Ltd. Gas shrouded wave improvement
DE19807696C2 (en) * 1998-02-24 2001-09-06 Manfred Fehrenbach Dip soldering process

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1110892A (en) * 1965-04-28 1968-04-24 British Aircraft Corp Ltd Improvements relating to wave soldering
GB1352746A (en) * 1970-11-02 1974-05-08 Electrovert Mfg Co Method and apparatus for soldering and tinning
GB2008013A (en) * 1977-08-31 1979-05-31 Frys Metals Ltd Improvements in wave soldering machines
GB2360237A (en) * 2000-03-16 2001-09-19 Evenoak Ltd Nozzle for soldering apparatus

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3113587A1 (en) * 2014-02-28 2017-01-04 Fuji Machine Mfg. Co., Ltd. Viscous fluid coating device
EP3113587A4 (en) * 2014-02-28 2017-03-29 Fuji Machine Mfg. Co., Ltd. Viscous fluid coating device
US9969023B2 (en) 2014-02-28 2018-05-15 Fuji Machine Mfg. Co., Ltd. Viscous fluid coating device
US20170209949A1 (en) * 2014-07-29 2017-07-27 Illinois Tool Works Inc. Soldering module
US10086460B2 (en) * 2014-07-29 2018-10-02 Illinois Tool Works Inc. Soldering module
US20220009017A1 (en) * 2020-07-08 2022-01-13 Illinois Tool Works Inc. Soldering nozzle, system and use

Also Published As

Publication number Publication date
NL1024476C2 (en) 2005-04-08
GB0422186D0 (en) 2004-11-03
GB2418881B (en) 2008-04-09
GB0422002D0 (en) 2004-11-03

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Date Code Title Description
PE20 Patent expired after termination of 20 years

Expiry date: 20241004