JPH07142855A - Vertical reflow soldering device - Google Patents

Abstract

PURPOSE:To prevent the defects in mounting and also, make the installation space of a device small by equipping this device with a carrier, which carries a printed board mounting electronic components in vertical direction, and arranging heaters on both sides of the carry path. CONSTITUTION:A printed board 10 to be soldered by reflow is placed on a holders 13 and 14 positioned at the bottoms of conveyors 11 and 12. And, this printed board 10 is carried vertically by the conveyors 11 and 12, and passes a preheating zone being the carry path of the printed board 10, a regular heating zone, and a cooling zone in order. This way, this takes such a constitution that the printed board is carried vertically and that it is heated from both sides of the carry path by the heater 20, the simultaneous heating of the printed boards 10 becomes possible, and solder paste can be heated and fused at the same time, and the dislocation of the surface mounting components or the mounting defects such as chip erection, etc., can be prevented. Moreover, the lateral width of the device becomes short, and the installation space becomes small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflow soldering apparatus, and in particular, it enables heating of solder paste on a printed circuit board at the same time and can prevent mounting defects such as displacement of surface-mounted components and chip standing. At the same time, it relates to a vertical reflow soldering device capable of reducing the installation space of the device.

[0002]

2. Description of the Related Art At present, in the field of electronic equipment industry, electronic components are mounted on the printed circuit board exclusively by reflow soldering because of the increase in the number of electronic components mounted on the printed circuit board and the necessity of mass production. The reflow soldering is a method in which an appropriate amount of solder is supplied in advance to a joint portion of an electronic component on a printed board and the solder is melted by a heat source from the outside to solder the electronic component. Then, such reflow soldering is performed by a reflow soldering device.

As shown in FIG. 2, the conventional reflow soldering apparatus transfers a printed circuit board 101 in a horizontal direction by a transfer conveyor 102 and a solder paste on the printed circuit board 101 transferred by the transfer conveyor 102. A preheating heater 103 for preheating, a main heating heater 104 having a fan for heating and melting the solder paste with hot air, and a cooling fan 105 for cooling and solidifying the solder paste that has been heated and melted. Was becoming.

[0004]

However, since the conventional reflow soldering apparatus described above is configured to heat the printed circuit board 101 while conveying it in the horizontal direction, the printed circuit board 101 shifts from preheating to main heating. At this time, a temperature difference occurs between the front side and the rear side of the printed circuit board 101 in the conveyance direction,
The solder paste on the printed board could not be heated at the same time. Therefore, in the two-electrode surface-mounted component mounted on the printed circuit board 101, the solder paste on the front side in the carrying direction of the printed circuit board 101 is partially melted first, and this molten solder paste is melted. There has been a problem that the surface-mounted component is pulled to the side and a mounting defect such as a positional shift or a chip standing occurs.

Further, the above conventional reflow soldering apparatus is
Since it is a horizontal type device that conveys the printed circuit board 101 in the horizontal direction, there is also a problem that a large installation space is required.

As a reflow soldering device for simultaneously heating a printed circuit board and a solder paste to prevent mounting defects of surface mount components, there are disclosed in JP-A-1-118370, JP-A-2-84292, and JP-A-2-142676. And Japanese Patent Application Laid-Open No. 3-35876. However, the reflow soldering devices of these publications are all horizontal devices, and the problem that the installation space is large has not been solved yet.

The present invention has been made in view of the above problems. The solder paste on a printed circuit board is heated at the same time to prevent misalignment of surface-mounted components, chipping, and other mounting defects, and to prevent the apparatus An object of the present invention is to provide a vertical reflow soldering device with a small installation space.

[0008]

In order to achieve the above object, a vertical reflow soldering apparatus of the present invention is configured to vertically convey a printed circuit board on which electronic components are mounted via a solder paste. And a heating unit that is disposed on both sides of the transport path of the transport unit and that heats and melts the solder paste on the printed circuit board, preferably, the transport unit,
The conveyors are arranged so as to face each other in a vertical state and driven in the same direction, and a holding portion that is provided so as to face the conveyors and holds the printed circuit board between the conveyors. Also, if necessary, the heating unit is configured to include a pre-heating unit and a main heating unit,
Further, a cooling unit for the printed circuit board is provided on the downstream side of the heating unit.

[0009]

According to the vertical reflow soldering apparatus of the present invention having the above construction, the printed circuit board is conveyed in the vertical direction by the conveying section and is uniformly heated by the heating section from both sides of the conveying path. Therefore, there is no difference in temperature between the front side and the rear side of the printed board in the conveying direction, and the solder paste on the printed board is also melted at the same time.

[0010]

Embodiments of the vertical reflow soldering apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a front sectional view showing a vertical reflow soldering apparatus of this embodiment. FIG. 2 is a side sectional view showing the vertical reflow soldering device.

In these drawings, 11 and 12 are conveyors (conveying units), which are arranged so as to face each other in a vertical state. These conveyors 11, 12
Is composed of two conveyor belts 11a and 11b (12a and 12b) which are suspended by rollers and circulate. And, these conveyor belts 11a, 1
1b, 12a, 12b are driven in the same direction (upward in this embodiment) to form a conveyance path for the printed circuit board 10 between the conveyors 11, 12. Also, the conveyor belt 11
The rotation speeds of a and 11b and the conveyor belts 12a and 12b are synchronized with each other.

Such conveyor belts 11a and 11b
And the long holding portion 1 is provided on the surfaces facing each other.
3,14 are erected. And these holding parts 1
The vertical cross sections of 3, 14 are L-shaped, and both holding portions 1
3 and 14 form a pair and hold both ends of the printed circuit board 10.

The heating unit 20 includes preheating units 21 and 22.
And main heating units 23 and 24, and fixed in a vertical line to fixing units 31 and 32 arranged in the conveyors 11 and 12. Preheating units 21 and 22 are provided at three positions on the conveyors 11 and 12 at the same height position, and main heating units 23 and 22 are located at the same height position and above the preheating units 21 and 22 (downstream side). 24 are arranged. Preheating section 21, 22
Is composed of heaters 21a and 22a and fans 21b and 22b, and blows hot air of about 150 ° C. to form a preheating zone.

The main heating units 23 and 24 are heaters 23.
a, 24a and fans 23b, 24b, and has substantially the same configuration as the preheating unit. However, the main heating unit 23,
The heaters 23a and 24a of 24 are preheating parts 21 and 22.
The output is made larger than that of the heaters 21a and 22a, and hot air of about 230 ° C. is blown to form the main heating zone.

Cooling fans (cooling parts) 41, 42 provided on the upper part (downstream side) of the heating part 20 blow cool air onto the printed circuit board 10 to form a cooling zone.
Reference numeral 50 denotes a ventilation part, which vents gas generated during soldering and air whose temperature has risen to the outside.

Next, the operation of the vertical reflow soldering apparatus having the above structure will be described. The printed circuit board 10 to be reflow-soldered is placed on the holders 13 and 14 located at the lower ends of the conveyors 11 and 12 from the carry-in port 60 at the bottom of the apparatus by a loader (not shown). Then, the printed circuit board 10 is conveyed in the vertical direction by the conveyors 11 and 12, and sequentially passes through a preheating zone, a main heating zone, and a cooling zone, which are conveyance paths of the printed circuit board 10.
First, in the preheating zone, the preheating units 21 and 22 form an atmosphere of about 150 ° C. by hot air,
Preheat 0. Next, in the main heating zone, the main heating unit forms an atmosphere of about 230 ° C. with hot air to heat and melt the solder paste on the printed circuit board 10. Then, in the cooling zone, the cooling fans 41 and 42 blow cold air,
The heat-melted solder paste is solidified to complete the reflow soldering. After that, the printed circuit board 10 is carried out of the apparatus from the carry-out port 70 by an unloader (not shown) when passing through the cooling zone.

According to such a vertical reflow soldering apparatus of this embodiment, the printed circuit board 10 is transported in the vertical direction and is heated from both sides of the transport path of the printed circuit board 10. It is possible to heat the solder paste on the printed circuit board 10 at the same time, and to prevent mounting defects such as displacement of surface-mounted components and chip standing. Further, since the conveyance path of the printed circuit board 10 is formed in the vertical direction, the lateral width of the device is reduced and the installation space is reduced.

The vertical reflow soldering apparatus of the present invention is not limited to the above embodiment. For example, although the conveyor belt is used as the conveyor in the above embodiment, other conveyors such as a chain may be used. Further, in the above embodiment, the method of heating and melting the solder paste on the printed circuit board 10 with hot air was adopted, but this is not particularly limited, and the method of heating with near infrared rays or far infrared rays or heating with vaporization latent heat Various heating methods such as a heating method can also be used.

[0019]

As described above, according to the vertical reflow soldering apparatus of the present invention, it is possible to simultaneously heat the solder paste on the printed circuit board, the positional displacement of the surface mount component, the chip standing, etc. It is possible to prevent defective mounting and to reduce the installation space of the device.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a vertical reflow soldering device according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing the vertical reflow soldering device.

FIG. 3 is a side sectional view showing a horizontal reflow soldering device according to a conventional example.

[Explanation of symbols]

 10 Printed Circuit Boards 11 and 12 Conveyors (Conveying Units) 11a, 11b, 12a and 12b Conveyor Belts 13 and 14 Holding Units 20 Heating Units 21 and 22 Preheating Units 21a and 22a Heaters 21b and 22b Fans 23 and 24 Main Heating Units 23a and 24a Heater 23b, 24b Fan 31,32 Fixed part 41,42 Cooling fan (cooling part) 50 Ventilation part 60 Carry-in port 70 Carry-out port

[Procedure amendment]

[Submission date] November 14, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

As shown in FIG. 3, a conventional reflow soldering apparatus transfers a printed circuit board 101 in a horizontal direction by a transfer conveyor 102 and a solder paste on the printed circuit board 101 transferred by the transfer conveyor 102. A preheating heater 103 for preheating, a main heating heater 104 having a fan for heating and melting the solder paste with hot air, and a cooling fan 105 for cooling and solidifying the solder paste that has been heated and melted. Was becoming.

Claims (4)

[Claims] 1. A transport section for vertically transporting a printed circuit board on which an electronic component is placed via a solder paste, and a transport section on both sides of the transport section for heating and melting the solder paste on the printed circuit board. A vertical reflow soldering device, comprising: 2. The conveyors, which are arranged so as to face each other in a vertical state and are driven in the same direction, and a holding device which is provided so as to face the conveyors and holds the printed circuit board between the conveyors. The vertical reflow soldering device according to claim 1, wherein the vertical reflow soldering device comprises: 3. The vertical reflow soldering device according to claim 1, wherein the heating section includes a preliminary heating section and a main heating section. 4. The vertical reflow soldering device according to claim 1, further comprising a cooling unit for the printed circuit board, which is provided on the downstream side of the heating unit.