JPH07336036A - Soldering apparatus - Google Patents

Abstract

PURPOSE:To obtain a soldering apparatus in which cooling of a circuit board in a chamber can be realized with a low cost. CONSTITUTION:The conveying outlet 21 of a soldering apparatus which has a conveying inlet 7 and the outlet 21 of a circuit board 1 and solders while conveying the board 1 by a conveyor has a chamber body 3 having a preheater 4 divided in the conveying direction and a solder tank 6, and a small chamber 18. The conveying inner port 8 side of the body 3 and the conveying inner port 20 of the chamber 18 are so connected by a tube 22 having heat insulation and flexibility sealingly with the chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering apparatus for soldering in a low oxygen concentration atmosphere covered with a chamber.

[0002]

2. Description of the Related Art The soldering process can be roughly divided into a flow soldering process and a reflow soldering process. Then, in order to realize no cleaning and micro soldering of the wiring board after soldering, an inert gas of low oxygen concentration (for example, nitrogen gas: N2) is used.
There are many examples of performing these soldering processes in an atmosphere. On the other hand, forming an atmosphere with a lower oxygen concentration with a smaller nitrogen gas consumption is an essential requirement for reducing the running cost of the soldering device.

Incidentally, an elevator mechanism is generally used in order to change the height position (level) at which a wiring board is transported or to adjust it to the height of the other transportation system. For example, in "Reflow device" disclosed in Japanese Patent Laid-Open No. 3-216269, a technique for transferring a wiring board between conveyors having different transfer levels by elevating a transfer conveyor is described.

In addition, as in the "soldering device" disclosed in Japanese Utility Model Laid-Open No. 63-150754, a peel-back point can be obtained by constructing a flow type soldering device so that the elevation angle can be varied and adjusted. There is a soldering device that can adjust the solder separation property in (3) to obtain optimum solderability.

In such a soldering apparatus having a wiring board carrying conveyor with an elevation angle, since the wiring board carry-in side conveyor height and the board carry-out side conveyor height are different,
A technique for transporting a wiring board to a predetermined height position using the elevator mechanism as described above is generally adopted.

Further, in Japanese Patent Publication No. 5-84080, "Printed Circuit Board Cooling and Transfer Device", a technique of providing a cooling fan for cooling the wiring board in the stocker portion constituting the elevator mechanism of the wiring board is described. There is.

[0007]

By the way, in order to carry out the soldering process in an atmosphere of an inert gas having a low oxygen concentration, the atmosphere in the chamber is shut off from the atmosphere, and the soldering is carried out while the wiring board is carried into the chamber. It is common to implement the attachment process. However, since the soldering process is a heating process, the temperature of the chamber and the atmosphere inside the chamber becomes high, and as a result, there is a disadvantage that it is difficult to quickly cool the wiring board after soldering.

For example, in the "reflow device" disclosed in Japanese Unexamined Patent Publication No. 3-216269, the transfer conveyor which moves up and down is placed in an atmosphere of high temperature, so that the wiring board which is not cooled is soldered. The wiring board is moved up and down while the strength (solder solidification) is insufficient, and the micro-vibration and shaking generated by the up-and-down operation easily give rise to obstacles such as cracks in the soldered portion. Further, in the technique of the publication, since the transfer conveyor is moved up and down in the chamber, the chamber volume becomes large and the apparatus cost tends to increase. Further, the lifting and lowering operation of the transfer conveyor causes outflow of nitrogen gas and inflow of outside air, which causes a so-called pumping action, which disturbs the atmosphere flow in the reflow device and makes the oxygen concentration unstable.

On the other hand, the "printed board cooling transfer device" of Japanese Patent Publication No. 5-84080 has an advantage that the wiring board can be moved down while being cooled by a cooling fan. However, the technique of directly blowing the cooling air onto the wiring board cannot be used in the tunnel-shaped chamber. That is,
This is because the atmospheric flow in the chamber that is controlled so as to form an equilibrium point at which the inflow of the atmosphere and the outflow of the atmosphere in the chamber are minimized will not be established due to the disturbance by the fan. Due to this, the predetermined oxygen concentration cannot be suppressed below the predetermined value unless the supply amount of the inert gas is extremely increased.

It is an object of the present invention to make it possible to effectively cool a wiring board in the chamber by dividing the tunnel-shaped chamber body, and to realize this at low cost. Another object of the present invention is to establish an optimum transfer technique between conveyors having different heights such as a soldering device that can adjust and adjust the elevation angle while having a tunnel chamber.

[0011]

The present invention is characterized in that the chamber body is divided and the transfer conveyor is moved up and down together with the chamber.

Therefore, according to the first aspect of the present invention, at least a portion of the carry-in port and the carry-out port of the chamber on the carry-out port side is divided in the carrying direction, and the chamber main body is provided with a heating device. The chamber is configured into three or more small chambers, and the divided chambers are hermetically connected in a chamber shape by a heat insulating member.

Further, the invention according to claim 2 is provided with a cooling device for cooling a portion connected by a heat insulating member.

According to a third aspect of the invention, the cooling device is liquid-cooled in the chamber body having the heating device,
A small chamber without a heating device is air-cooled.

Further, the invention according to claim 4 is one in which the conveyer conveyor is divided according to the number of divisions of the chamber.

According to the invention described in claim 5, the small chamber is provided with an elevating device capable of elevating.

[0017]

According to the first aspect of the present invention, the temperature of the small chamber is relatively low because the chamber body provided with the heating device and the small chamber are thermally insulated. Therefore, the wiring board can be easily cooled. Further, even when the chamber on the carry-in side of the chamber body is divided and thermally insulated, the temperature of the chamber on the carry-in side is relatively low, and the controllability of the heating profile is improved.

Further, according to the second aspect of the present invention, since the portion of the chamber connected by the heat insulating member is cooled, the heat insulating property of the small chamber and the environment for cooling the wiring board are further improved. Furthermore, since the heat insulating member is not exposed to high temperature, the durability of the heat insulating member is improved.

In addition, in the invention described in claim 3, since the liquid cooling has a large heat exchange capacity, it is optimal for cooling the chamber main body equipped with the heating device, and the small chamber can be sufficiently cooled even by air cooling. Is possible, and the cost of the cooling device and cooling is low.

Further, according to the invention described in claim 4, since the transfer conveyor is divided according to the number of chambers to be divided, it is possible to block the conductive heat from the transfer conveyor and cool the wiring board. It can be done easily.

Further, according to the fifth aspect of the present invention, since the small chamber and the small conveyer can be moved up and down in an airtight state, wiring between conveyors having different heights can be performed without disturbing the atmosphere flow in the small chamber. It becomes possible to transfer the substrate.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the soldering apparatus according to the present invention will be described below with reference to the drawings. 1 to 3 show an embodiment of the present invention. FIG. 1 is a side sectional view showing a case where a divided small conveyor is in a raised position, and FIG. 2 shows a main part of FIG. FIG. 3 is an enlarged sectional view showing the same, and FIG. 3 is a side sectional view showing a case where the small conveyor is in the lowered position. Although FIG. 1 illustrates the case of a flow type soldering device, a reflow type soldering device can be similarly configured.

In these drawings, reference numeral 1 is a wiring board, 2 is a housing, and a tunnel-shaped chamber body 3 is provided in the housing 2, and a preheater 4 for preheating and a solder are provided in the chamber body 3. A solder bath 6 provided with a heating device (not shown) for forming the jet wave 5a of the melt 5 is provided, and the carrier conveyor 9 is penetrated from the carry-in port 7 of the chamber body 3 to the carry-out inner port 8. It is arranged. The conveyor 9 has a structure in which the wiring board 1 is sandwiched by the claw pieces. Further, the chamber body 3 is provided with a suppressing plate 10 for suppressing unnecessary atmospheric convection, and forms a so-called labyrinth flow path. Further, an inert gas supply port 11 is provided near the solder bath 6, and an inert gas such as N2 gas is introduced into the chamber body 3 to form an atmosphere of low oxygen concentration.

On the other hand, a fulcrum shaft 12 for rotatably holding the chamber body 3 is provided on the carry-in port 7 side of the chamber body 3, and the chamber body 3 is provided on the carry-out inner port 8 side of the chamber body 3.
An elevating device 13 is provided for adjusting the elevation angle θ (inclination angle) of the. The lifting device 13 includes a threaded rod 14 and a handle 15, and the threaded rod 13 is screwed to a base member 16 that constitutes the housing 2. Further, the solder bath 6 is also the base member 1
An elevating device 17 composed of a screw rod 14 and a handle 15 screwed to the 6 is configured to be adjustable up and down. Since the transfer conveyor 9 is configured to be fixed to the chamber body 3,
The elevation angle θ can be adjusted by adjusting the inclination of the chamber body 3. Further, 18 is a small chamber formed by dividing the carry-in inlet 8 side of the chamber body 3 in the carrying direction, 19 is a small conveyer on the divided side, 20 is a carry-in inner port, and 21 is a carry-out port. .

Further, between the carry-in inner port 8 of the chamber body 3 and the carry-in inner port 20 of the small chamber 18 on the divided side, a rubber member or a resin member such as silicon rubber having heat insulating property and flexibility. The pipes 22 made of the same material are connected in a chamber shape.
Then, an actuator 23 such as an air cylinder is attached to the base 24 of the small chamber 18, and the actuator 23 is driven to move the small chamber 18 and the small transfer conveyor 19 for transfer up and down. Incidentally, the small chamber 18 is provided with the restraint plate 10 forming the labyrinth flow path and the nozzle 25 forming the air curtain.

Further, in order to cool the connection opening portion of the chamber main body 3 on the side of the carry-out inside opening 8, a cooling unit 27 through which cooling water 26 is passed is provided. Further, in order to cool the small chamber 18, the fan 28 shown in FIG. 2 is provided on the base 24 so that the air delivered by the fan 28 is blown against the small chamber 18.

On the other hand, an entry sensor S1 for detecting the transfer of the wiring board 1 to the small transfer conveyor 19 and an output sensor S2 for detecting the transfer of the wiring board 1 from the small transfer conveyor 19 to the unloading side conveyor 29 are provided. Prepare for the small chamber 18.
Further, there are a lower limit sensor S4 for detecting that the small chamber 18 is at the lower limit position, that is, the height H2, and an upper limit position, that is, the height H3 on the carry-out inlet 8 side of the conveyor 9 in the chamber body 3. An upper limit sensor S3 for detecting this is provided. The upper limit sensor S3 for detecting the height H3 is attached to the chamber main body 3 by a supporting member shown by a broken line, and the height thereof changes with the adjustment of the elevation angle θ of the conveyor 9.

By the way, in FIGS. 1 and 2, the soldering device is arranged and operated in-line, and the height H1 of the conveyor 30 on the carry-in port 7 side and the carry-out port 2 are shown.
The height H2 of the first side conveyor 29 is 900 mm.

In the flow soldering apparatus shown in FIG. 1, the chamber body 3 does not change its inclination,
It may be fixed at a fixed elevation angle θ, and in this case, the fulcrum shaft 12 is unnecessary.

The small chamber 18 on the divided side may be fixed without moving up and down. Therefore, the transfer conveyor may have a single continuous structure from the carry-in port 7 of the chamber body 3 to the carry-out port 21 of the small chamber 18, and as shown in FIG. The configuration may be divided into 19 and.

A reflow-type soldering device (not shown) for horizontally transporting a wiring board is also composed of a chamber body and a divided small chamber, like the flow-type soldering device. It may be provided, and the chamber body and the small chamber are hermetically connected by a heat insulating member. Also in this case, the transport conveyor may have one continuous structure or a divided structure.

Further, in FIG. 1, a small chamber (not shown) may be provided by dividing the carry-in port 7 side of the chamber body 3 and connecting with a heat insulating material. Even in this case, the divided side may be provided. The temperature of the small chamber is also lowered, and the controllability of the heating profile is improved.

Next, the operation will be described.

The chamber body 3 and the small chamber 18 are connected to each other by a tube body 22 made of a rubber member so as to be heat-insulated, airtight and movable up and down. Water cooling unit 2
7. A fan 28 for cooling the connection opening portion of the small chamber 18 on the carry-in inlet 20 side is provided.

Therefore, the heat insulation between the chamber body 3 and the small chamber 18 is perfect, and the wiring board 1 can be cooled quickly in the small chamber 18. In addition, since the atmosphere flow in the chamber body 3 and the small chamber 18 is not disturbed by this cooling, a stable atmosphere can be maintained.

Further, since the tubular body 22 is cooled, the rubber member is not exposed to high temperature, and deterioration of the member due to bending due to the lifting operation can be suppressed to improve durability and reliability. it can.

Furthermore, since the entire small conveying conveyor 19 and the small chamber 18 are moved up and down, there is no pumping action for letting out an inert gas or inflowing outside air, which is caused by the raising and lowering operation as in the conventional example. A stable atmosphere can be maintained without any disturbance to the atmosphere inside the small chamber 18 associated with the lifting operation.

Next, the transfer timing of the wiring board 1 will be described. The wiring board 1 carried in from the carry-in port 7 and carried in the chamber main body 3 by the carrying conveyor 9 is preheated by the preheater 4 and then contacted with the jet wave 5a to be soldered, and then comes out from the carry-out inner port 8. come. Then, it is transferred to the small transfer conveyor 19, and when the transfer is confirmed by the entry sensor S1, the driving of the small transfer conveyor 19 is stopped. When the actuator 23 is driven and the small chamber 18 is lowered to the position H2 corresponding to the lower limit sensor S4, the lowering is stopped and the driving of the small conveyor 19 is started. As a result, the wiring substrate 1 held on the small transport conveyor 19 is transferred to the carry-out side conveyor 29, and when the transfer is detected by the carry-out sensor S2, the actuator 23 is driven to raise the small chamber 18, and the upper limit is reached. It stops at the position H3 corresponding to the sensor S3 and waits for the next wiring board 1 to enter.

That is, by repeating the above operation, the conveyors 9 and the small conveyors 1 having different heights are provided.
9. The wiring board 1 can be transferred between the unloading side conveyor 29. Since the position of the upper limit sensor S3 changes depending on the elevation angle θ, even when the elevation angle θ is adjusted / changed, the transfer conveyor is stopped at the adjusted height H3 and stands by.

The control unit for controlling these operations is omitted and not shown. It can be easily configured with a sequencer, programmable controller, microcomputer system, etc.

[0041]

As described above, the invention according to claim 1 of the present invention is provided with a heating device by dividing at least a portion of the carry-in port and the carry-out port on the carry-out port side in the carrying direction. The chamber main body and two or more small chambers are air-tightly connected to each other by a heat insulating member between the divided chambers, so that the temperature of the small chamber becomes relatively low and the wiring board is cooled. It can be easily performed and the controllability of the heating profile is improved.

Since the chamber is divided into a chamber body and a small chamber, the length of the entire chamber is the same as that of the conventional chamber.

Further, according to the second aspect of the present invention, since the cooling device for cooling the portion connected by the heat insulating member is provided, the heat insulating property of the small chamber and the cooling environment are further improved.
Further, since the heat insulating member is not exposed to high temperature, the durability of the heat insulating member is improved.

According to the third aspect of the invention, the cooling device is liquid-cooled in the chamber body having the heating device,
Since the small chamber without a heating device is configured by air cooling, cooling of the chamber body is effective, and the small chamber is sufficiently cooled even by air cooling, and the cost of the cooling device and the cost of cooling are low.

Further, according to the invention of claim 4, since the transfer conveyor is divided according to the number of chambers to be divided, it is possible to block the conduction heat from the transfer conveyor to the small transfer conveyor, and the wiring board Can be easily cooled.

According to the fifth aspect of the present invention, since the small chamber is provided with an elevating device capable of ascending / descending, the heights of the chamber body and the small chamber are different from each other without causing disturbance to the atmosphere flow. There is an advantage that the wiring board can be transferred between the conveyors.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a main part of FIG.

FIG. 3 is a side sectional view showing a case where the conveyor of FIG. 1 is in a lowered position.

[Explanation of symbols]

 1 Wiring Board 3 Chamber Body 4 Preheater 5 Solder Melt 5a Jet Wave 6 Solder Tank 7 Carrying Inlet 8 Carrying Out Inlet 9 Transport Conveyor 12 Support Shaft 13 Lifting Device 17 Lifting Device 18 Small Chamber 19 Small Transporting Conveyor 20 Carrying Inlet 21 Carrying Outlet 22 Tubular body 23 Actuator 26 Cooling water 27 Cooling unit 28 Fan

Claims (5)

[Claims] 1. A soldering device for soldering the wiring board in the chamber while the wiring board is being carried by a carrying conveyor in a chamber having a carry-in port and a carry-out port for the wiring board. Of the carry-in port and the carry-out port, at least the part on the carry-out port side is divided in the carrying direction to form a chamber body provided with a heating device and two or more small chambers, and a heat insulating member is provided between the divided chambers. A soldering device, characterized in that the chamber is hermetically connected in a chamber. 2. The soldering device according to claim 1, further comprising a cooling device that cools a portion connected by a heat insulating member. 3. The soldering apparatus according to claim 2, wherein the cooling device is liquid-cooled in the chamber body having the heating device, and is air-cooled in the small chamber having no heating device. 4. The soldering apparatus according to claim 1, wherein the transfer conveyor is divided according to the number of divisions of the chamber. 5. The soldering apparatus according to claim 1, wherein the small chamber is provided with an elevating device capable of ascending and descending.