JP5031603B2 - Trap device and reflow furnace - Google Patents

Description

  The present invention relates to a trap device that removes flux in a high-temperature gas that passes through an exhaust pipe, and a reflow furnace that includes the trap device.

FIG. 8 shows a schematic configuration of a conventional reflow furnace.
As shown in FIG. 8, the reflow furnace includes a heating chamber 400 that heats a substrate 100 (hereinafter referred to as an electronic component mounting substrate) on which electronic components are mounted via a bonding material. In general, in the heating chamber 400, a transport unit 200 that transports the electronic component mounting substrate 100 and a heating unit 300 that heats the transported electronic component mounting substrate 100 are disposed. By heating the electronic component mounting substrate 100 in the heating chamber 400, the flux contained in the bonding material is vaporized to bond the electronic component and the substrate.

  In addition, an exhaust pipe 500 for discharging the high temperature gas in the heating chamber 400 to the outside is disposed on the outer wall of the heating chamber 400. The exhaust pipe 500 is provided with a valve 600 for adjusting the exhaust flow rate. By adjusting the exhaust flow rate by operating this valve 600, the temperature in the heating chamber 400 can be adjusted and the atmosphere can be secured.

  By the way, the flux contained in the bonding material is vaporized in a high temperature state immediately after being heated in the heating chamber 400, but when the flux is cooled as it passes through the exhaust pipe 500, It adheres by liquefying or solidifying. Then, if the flux adheres and accumulates in the exhaust pipe 500, there is a possibility that problems such as a reduction in exhaust capability may occur. The cleaning operation for removing the flux adhering to the inner surface of the exhaust pipe 500 requires a lot of time and labor. Moreover, it is not preferable from an environmental viewpoint to discharge the high temperature gas mixed with the flux as it is to the outside.

Therefore, as shown in FIG. 8, a trap device 700 that removes the flux in the high-temperature gas is disposed in the exhaust pipe 500, and the flux is removed from the high-temperature gas by the trap device 700 (see, for example, Patent Document 1). ).
JP-A-9-307224

  A trap apparatus 700 shown in FIG. 8 is disposed on the downstream side of the valve 600. For this reason, when the vaporized flux is cooled to the solidification temperature in the vicinity of the valve 600, the flux adheres to the inner surface of the valve 600. And if flux adheres and accumulates in the valve 600, the valve 600 is clogged and the temperature inside the heating chamber 400 cannot be adjusted properly. There is also a problem that the operability of the valve is lowered due to the adhered flux.

  Therefore, in view of the above problems, the present invention provides a trap device for preventing flux from adhering to a valve of an exhaust pipe, and a reflow furnace equipped with the trap device.

The invention of claim 1 is a trap device for removing the flux in the high-temperature gas passing through the exhaust pipe, the casing main body disposed upstream of the valve attached to the exhaust pipe and the casing main body. A casing having a lid disposed detachably, a spindle attached to the lid and disposed in the casing main body, and removably attached to the spindle and meandering in the casing main body And a cylindrical spacer member interposed between the interference plates and removably attached to the support shaft.

With the trap device, the flux in the hot gas can be removed upstream of the valve. Thereby, it can prevent or suppress that a flux adheres to a valve | bulb.
In addition, by passing the hot gas in a meandering manner through the casing, the exhaust passage for the hot gas can be lengthened, and the hot gas can be cooled in the casing. By cooling the high temperature gas in the casing, the flux mixed in the high temperature gas is also cooled, and the flux can be liquefied or solidified on the interference plate, the inner surface of the casing, or the like.

  Further, the interference plate, the spacer member, and the support shaft can be detached from the casing body integrally with the lid. Furthermore, it is possible to remove the interference plate and the spacer member from the support shaft. As described above, since each member is configured to be separable, maintenance work such as cleaning of the flux adhered to each member can be easily performed.

A second aspect of the present invention is the trap apparatus according to the first aspect , wherein a plurality of types of the spacer members having different axial lengths are provided.

  By changing the length of the spacer member in the axial direction, the number of interference plates attached to the support shaft can be changed. Thereby, the length of the meandering flow path in the casing can be adjusted. For example, by adopting a spacer member having a short axial length, the number of interference plates attached to the support shaft can be increased, and the meandering channel can be lengthened. Thereby, the high-temperature gas in which the flux is mixed can be reliably cooled, and the flux removal rate can be increased. Further, if a spacer member having a long axial direction is employed, the number of interference plates attached to the support shaft can be reduced. Thereby, the number of interference plates attached can be set to the number required to remove the flux, and the exhaust resistance due to the interference plates can be prevented from increasing wastefully.

A third aspect of the present invention is the trap apparatus according to the first or second aspect , wherein the casing is provided with a window portion made of a transparent member.

  It is possible to confirm the amount of flux adhered in the casing from the outside through the window portion. Thereby, it is possible to grasp | ascertain easily and appropriately the maintenance time which cleans the inside of a casing.

According to a fourth aspect of the present invention, in the trap device according to any one of the first to third aspects, a cooling means for cooling at least one of the casing and the interference plate is provided.

  By cooling at least one of the casing and the interference plate, the heated gas passing through the casing can be efficiently cooled, and the removal rate of the flux in the high-temperature gas can be increased. Thereby, adhesion of the flux to a valve | bulb can be prevented reliably.

According to a fifth aspect of the present invention, in the trap device according to any one of the first to fourth aspects, at least one of the casing and the interference plate is made of a good thermal conductor.

  Thereby, at least one of the casing and the interference plate can be efficiently cooled, and the removal rate of the flux in the high-temperature gas can be further increased.

According to a sixth aspect of the present invention, a flux contained in the bonding material is vaporized by heating an electronic component mounting substrate formed by mounting an electronic component on the substrate via a bonding material, whereby the electronic component and the substrate are separated from each other. In a reflow furnace comprising a heating chamber to be joined, an exhaust pipe for discharging a high-temperature gas mixed with the vaporized flux from the heating chamber, and a valve for adjusting an exhaust flow rate of the exhaust pipe, A trap device for removing flux mixed in the high-temperature gas is disposed upstream of the valve, and the trap device is detachably disposed on the casing body disposed in the exhaust pipe and the casing body. A casing having a cover body, a spindle attached to the lid body and disposed in the casing body, removably attached to the spindle and front A plurality of interference plate forming a serpentine flow path in the casing body, in which a removably attached tubular spacer member to the support shaft with interposed therebetween of the interference plate .

  With the trap device, the flux mixed in the high temperature gas can be removed on the upstream side of the valve. Thereby, it can prevent or suppress that a flux adheres to a valve | bulb.

  By passing the hot gas in a meandering manner through the casing, the exhaust passage for the hot gas can be lengthened, and the hot gas can be cooled in the casing. By cooling the high temperature gas in the casing, the flux mixed in the high temperature gas is also cooled, and the flux can be liquefied or solidified on the interference plate, the inner surface of the casing, or the like.

  Further, the interference plate, the spacer member, and the support shaft can be detached from the casing body integrally with the lid. Furthermore, it is possible to remove the interference plate and the spacer member from the support shaft. As described above, since each member is configured to be separable, maintenance work such as cleaning of the flux adhered to each member can be easily performed.

  According to the trap device of the present invention and the reflow furnace equipped with the trap device, the flux in the high temperature gas is removed on the upstream side of the valve, so that the flux can be prevented or suppressed from adhering to the valve. Thereby, it is possible to prevent the valve from being clogged and the operability of the valve from being lowered due to the flux adhering to the valve.

Hereinafter, the configuration of the reflow furnace of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a front view of a reflow furnace equipped with the trap device of the present invention. As shown in FIG. 1, the reflow furnace includes a heating chamber 1 and an exhaust pipe 2. In the heating chamber 1, similarly to the above-described conventional configuration, a transport unit that transports the electronic component mounting substrate and a heating unit that heats the transported electronic component mounting substrate are disposed (not shown).

  The electronic component mounting substrate is formed by mounting an electronic component on a substrate via a bonding material. Moreover, the silver paste containing a flux is employ | adopted for the joining material.

  The exhaust pipe 2 has a plurality of branched branch pipes 3, and each branch pipe 3 is disposed on the outer wall of the heating chamber 1. Each branch pipe 3 is provided with a valve 4 for adjusting the exhaust flow rate. The temperature in the heating chamber 1 can be adjusted by operating the valve 4 to adjust the exhaust flow rate of each branch pipe 3.

  Further, a trap device 5 for collecting the flux vaporized from the bonding material is disposed upstream of the position where the valve 4 of each branch pipe 3 is disposed, that is, on the heating chamber 1 side.

  FIG. 2 is a sectional side view of the trap device 5. As shown in FIG. 2, the trap device 5 includes a casing 6 and a plurality of interference plates 7 disposed in the casing 6. The casing 6 includes a casing body 8 having a cylindrical inner space, and a lid 9 that is detachably disposed at one end of the casing body 8. At both ends of the peripheral wall portion of the casing body 8, vent holes 10a and 10b are respectively provided. A branch pipe 3 is connected to one vent 10a, and a pipe 11 disposed on the outer wall of the heating chamber 1 is connected to the other vent 10b.

  The plurality of interference plates 7 are attached to the lid body 9 via the support shaft 12. A plurality of spacer members 13 for arranging the interference plates 7 at predetermined intervals are attached to the support shaft 12. The lengths of the spacer members 13 in the axial direction are all set to the same length. Thereby, the interference plates 7 are arranged at equal intervals.

  A bearing portion 14 projects from the center of the lid body 9, and the tip end of the support shaft 12 is attached to the bearing portion 14. The lid 9, the support shaft 12, the interference plate 7, and the spacer member 13 are detachably attached to the casing body 8 as a unit.

  3A and 3B are views showing a state in which the unit including the lid body 9 and the interference plate 7 is removed from the casing main body 8. FIG. 3A is a side sectional view of the unit, and FIG. FIG.

  Moreover, the cover body 9, the support shaft 12, the interference plate 7, and the spacer member 13 which comprise the said unit are each comprised so that isolation | separation is possible. FIG. 4 shows a state where these members are separated.

  As shown in FIGS. 3 and 4, the interference plate 7 is formed of a circular plate-like member in which a U-shaped cutout 15 is formed. This notch 15 functions as an air passage through which high-temperature gas passes in the casing 6. Further, instead of the notch 15, a through hole may be formed in the interference plate 7. Alternatively, it is also possible to provide a gap between the edge of the interference plate 7 and the inner surface of the casing body 8 and use this gap as the ventilation path.

  In a state where the interference plate 7 is mounted on the support shaft 12, the notches 15 of the adjacent interference plates 7 are disposed on opposite sides of 180 °. By arranging the notches 15 in this way, a meandering flow path is formed in the casing body 8 (see FIG. 3A).

  In the center of the interference plate 7, an insertion hole 16 for inserting the support shaft 12 is provided. The spacer member 13 is a cylindrical member interposed between the interference plates 7 and can be inserted into and removed from the support shaft 12.

  The bearing portion 14 has an insertion hole 17 in which a female screw portion is formed at the tip thereof. On the other hand, the support shaft 12 has a male screw portion for screwing onto the female screw portion of the bearing portion 14 at least at the tip thereof. Further, at the base end of the support shaft 12, a retaining portion 18 that is enlarged in the radial direction is provided so that the interference plate 7 and the spacer member 13 attached to the support shaft 12 do not fall off.

  An annular groove is formed on the back surface of the lid 9, and an annular seal member 19 made of rubber or the like for sealing the inside of the casing body 8 is attached to the annular groove. The lid 9 has two through holes 20, and a fixing tool 24 such as a bolt (see FIG. 2) is inserted into each through hole 20 and attached to the casing body 8.

  FIG. 5 is a view showing another embodiment of the trap device 5. In this embodiment, the trap device 5 includes a cooling means 22 that cools the casing 6. The cooling means 22 is, for example, a cooling jacket 23 disposed on the outer periphery of the casing body 8. The cooling jacket 23 has a supply port 23a for supplying a cooling medium such as cooling water and a discharge port 23b for discharging the supplied cooling medium. Moreover, the cooling means 22 may blow air, cold air, etc. from the outer side of the casing 6 (illustration omitted). In addition to cooling the casing 6 from the outside, the casing 6 may be cooled from the inside via the support shaft 12, the interference plate 7, and the like. Furthermore, in order to cool the trap apparatus 5 efficiently, each member such as the casing body 8 and the interference plate 7 constituting the trap apparatus 5 may be formed of a good heat conductor such as copper, aluminum, or an alloy containing them. Good.

  FIG. 6 is a view showing still another embodiment of the trap device 5. In the trap device 5 of this embodiment, a window portion 21 made of a transparent member such as heat resistant glass is provided on the peripheral wall portion of the casing body 8. The shape, size, arrangement position, and the like of the window portion 21 are not limited to those illustrated.

Hereinafter, the operation of the reflow furnace of the present invention will be described.
In the heating chamber 1, the electronic component mounting substrate is heated while being conveyed. By this heating, the flux contained in the bonding material is vaporized, whereby the electronic component and the substrate are bonded. The hot gas in the heating chamber 1 is discharged to the outside through the plurality of branch pipes 3 of the exhaust pipe 2. The temperature in the heating chamber 1 is adjusted by operating the valve 4 in advance to adjust the exhaust flow rate of the branch pipe 3.

  The high-temperature gas in the heating chamber 1 is mixed with flux evaporated from the bonding material. When this hot gas is exhausted, it passes through the casing 6 of the trap device 5 disposed on the upstream side of the valve 4. In the casing 6, a meandering flow path is formed by a plurality of interference plates 7 provided with notches 15 on the opposite sides of 180 °. Thus, the hot gas can be cooled in the casing 6 by arranging the exhaust passage in the casing 6 in a meandering manner and lengthening it. By cooling the high temperature gas in the casing 6, the flux mixed in the high temperature gas is also cooled, and the flux can be liquefied or solidified on the interference plate 7, the inner surface of the casing 6, or the like. Thereby, the flux in high temperature gas can be removed.

  Thus, it is possible to prevent or suppress the flux from adhering to the valve 4 by removing the flux in the high temperature gas on the upstream side of the valve.

  When the trap device 5 shown in FIG. 5 is used, the heating gas passing through the casing 6 can be efficiently cooled by supplying cooling water or the like into the cooling jacket 23. Thereby, the removal rate of the flux in high temperature gas can be raised, and adhesion of the flux to the valve | bulb 4 can be prevented reliably.

  Moreover, as shown in FIG. 6, when the window part 21 is provided in the casing 6, the quantity of the flux which adhered in the casing 6 from the outside through the window part 21 can be confirmed. Thereby, it is possible to easily and appropriately grasp the maintenance time for cleaning the inside of the casing 6.

  As described above, the interference plate 7 can be attached to and detached from the casing body 8 integrally with the lid body 9. By removing the fixture 24 that attaches the lid body 9 to the casing body 8 and separating the lid body 9 in the axial direction of the casing body 8, the plurality of interference plates 7 and the like can be slid out of the casing body 8. it can. Further, the interference plate 7 and the spacer member 13 can be extracted from the tip of the support shaft 12 by removing the tip of the support shaft 12 from the bearing portion 14. Thus, by separating the members constituting the trap device 5, maintenance work such as cleaning of the flux adhering to these members can be easily performed.

  A plurality of types of spacer members 13 having different axial lengths may be provided. For example, the axial length L2 of the spacer member 13 shown in FIG. 7 is set to be smaller than the axial length L1 of the spacer member 13 shown in FIG. By adopting the spacer member 13 having the small axial length L2 shown in FIG. 7, the interval between the interference plates 7 is narrowed, so that the number of the interference plates 7 attached to the support shaft 12 can be increased. By increasing the number of the interference plates 7 attached, the meandering flow path of the hot gas in the casing 6 becomes longer. Thereby, the flux mixed in the high-temperature gas can be cooled more reliably, and the flux removal rate can be increased.

  Further, if the spacer member 13 having a long axial length is employed, the number of interference plates 7 attached to the support shaft 12 can be reduced. Thereby, the number of attachments of the interference plate 7 is set to the number necessary for removing the flux, and the exhaust resistance due to the interference plate 7 can be prevented from increasing unnecessarily.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention. In order to more reliably prevent the flux from being discharged to the outside, a trap device different from the trap device disposed on the upstream side of the valve may be disposed near the outlet of the exhaust pipe.

It is a front view of the reflow furnace provided with the trap apparatus of this invention. It is a cross-sectional side view of the reflow furnace. It is a figure which shows the state which extracted the interference board from the casing main body of the said trap apparatus, Comprising: (a) is the cross-sectional side view, (b) is the back view. It is an exploded view of the parts which constitute the trap device. It is a cross-sectional side view which shows other embodiment of the said trap apparatus. It is a side view which shows another embodiment of the said trap apparatus. It is a cross-sectional side view which shows the Example which used the spacer member with short axial direction length for the said trap apparatus. It is a schematic block diagram of the conventional reflow furnace.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heating chamber 2 Exhaust pipe 4 Valve 5 Trap apparatus 6 Casing 7 Interference plate 8 Casing body 9 Lid 12 Spindle 13 Spacer member 21 Window 22 Cooling means

Claims (6)

A trap device for removing flux in hot gas passing through an exhaust pipe,
A casing having a casing body disposed on the upstream side of a valve attached to the exhaust pipe, a cover body detachably disposed on the casing body, and attached to the lid body and disposed in the casing body A support shaft, a plurality of interference plates that are removably attached to the support shaft and that form a meandering flow path in the casing body, and are interposed between the interference plates and are inserted into and removed from the support shaft. A trap device comprising a cylindrical spacer member attached in a possible manner . The trap apparatus according to claim 1, comprising a plurality of types of the spacer members having different axial lengths . The trap apparatus of Claim 1 or 2 which provided the window part which consists of a transparent member in the said casing . The trap apparatus according to any one of claims 1 to 3, further comprising a cooling unit that cools at least one of the casing and the interference plate . The trap apparatus of any one of Claim 1 to 4 which comprised at least one of the said casing and the said interference board with the heat good conductor . A heating chamber for vaporizing the flux contained in the bonding material by heating the electronic component mounting substrate formed by mounting the electronic component on the substrate via the bonding material, and bonding the electronic component and the substrate; In a reflow furnace comprising an exhaust pipe for discharging a high-temperature gas mixed with vaporized flux from the heating chamber, and a valve for adjusting an exhaust flow rate of the exhaust pipe,
  A trap device for removing flux mixed in the high-temperature gas is disposed on the upstream side of the valve of the exhaust pipe,
The trap device includes a casing main body disposed in the exhaust pipe and a casing having a lid detachably disposed on the casing main body, a support shaft attached to the lid body and disposed in the casing main body. A plurality of interference plates that are removably attached to the support shaft and that form a meandering flow path in the casing body, and are interposed between the interference plates and removably attached to the support shaft. A reflow furnace comprising a cylindrical spacer member.

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