JPH0831688B2 - Hot air box with reflow soldering - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel hot air box with reflow soldering. Specifically, a new reflow soldering method that makes the hot air sent from the hot air generator a swirl flow inside the box so that the hot air blowout from the multiple hot air outlets can be generally stable and uniform It is intended to provide a hot air box.

[0002]

2. Description of the Related Art In a conventional open type reflow soldering apparatus, electronic parts are placed on a heated iron plate and a board coated with cream solder is passed through, and the board heats the board from below to heat the cream. Soldering is performed by reflowing the solder.

[0003]

However, in the above-mentioned conventional open type reflow soldering apparatus, when the board is deformed by warping or the like, the board and the heated iron plate do not come into close contact with each other. However, there is a problem that soldering failure occurs.

For this reason, a warp correction jig or the like must be used, and there is a drawback that the work becomes complicated.

Further, if there is a portion (lead tip) protruding downward of the board like the lead component, it is impossible to bring the heated iron plate and the substrate into close contact with each other, so that the lead component cannot be soldered. There are also problems.

Therefore, there is an atmosphere furnace type reflow soldering device that allows a substrate to pass through a heating furnace. According to this system, soldering is possible even if the substrate is deformed due to warp, etc. It is also possible to solder components.

However, in the reflow soldering apparatus of the atmospheric furnace type, there are some problems caused by heating the entire substrate to perform reflow.

That is, since the entire substrate is heated, partial soldering is impossible.

Further, there is a problem in that it is impossible to solder a heat-sensitive portion, and further, a large thermal stress is applied to the component, and particularly in the case of twice reflow, the reliability of the component is remarkably lowered.

[0010]

In order to solve the above-mentioned problems, the reflow soldering hot air box of the present invention is provided with a hot air box into which hot air from the hot air generator flows. The cream solder is reflowed by hot air blown out from a plurality of hot air blowout holes formed in a plate arranged so as to cover the opening.

Further, a hot air generator is connected to the opposite surface of the hot air box such that the axes of the hot air box and the hot air box are different from each other so that a swirl flow of the air that has become the hot air and flows into the hot air box occurs. Is.

[0012]

Therefore, according to the hot air box with reflow soldering according to the present invention, since the parts are soldered at the position separated from the hot air box, the soldering of the lead parts, especially the lead parts and the chip parts are mixed. Simultaneous soldering or spot-like soldering is possible, and not only is it possible to solder parts that are weak to heat, but it also creates a swirl of the air that has flowed in as hot air in the hot air box. Since it is possible to stabilize the blowing of hot air from the plurality of hot air blowing holes,
It also becomes possible to make them uniform.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the hot air box with reflow soldering according to the present invention will be described below with reference to the embodiments shown in the accompanying drawings.

Reference numeral 1 denotes a hot air blowing section, which comprises a hot air box 2 and a hot air generator 3 attached to the hot air box 2.
3 and 3.

The hot air box 2 has a rectangular box shape in plan view.

The portion of the hot air box 2 excluding the upper surface portion has a double structure, the inner side 4 is formed by a heat insulating material such as asbestos, and the axial lines of the hot air generators 3 and 3 among the corners of the inner surface. The portion where is abutted is made into a concave curved surface 32, 32, and the outer side 5 is made of aluminum.

The upper surface is formed by a lower plate 6 formed of a heat insulating material and an upper plate 7 formed of a brass plate or the like, and the upper opening of the hot air box 2 is covered by the upper plate 7. ing.

The lower plate 6 is formed in a frame shape, leaving only its peripheral portion.

The hot air generator 3 includes a transparent quartz tube 8, a shield stainless pipe 9 surrounding the outer periphery thereof, and a heater element 1 supported along the center of the transparent quartz tube 8.
0, so that the heater element 10 is energized.

The hot air generator 3 formed as described above,
One end of 3 is connected to the opposite surface portions of the hot air box 2 and their axes are different from each other, and the other end is connected to the air compressors 31, 31.

Guide rails 11 and 11 are attached to the upper surface of the upper plate 7 of the hot air box 2 and are arranged at intervals so as to be parallel to each other. Extending guide grooves 12, 12 are formed.

.. are formed in the upper plate 7 of the hot air box 2 between the guide rails 11 and 11.

Therefore, when air is supplied to the hot air generators 3 and 3 and the heater elements 10 and 10 are energized,
The air supplied from the other ends of the hot air generators 3 and 3 becomes hot air and flows into the hot air box 2 from one end.

At that time, the hot air generators 3 are provided in the hot air box 2
Since the axes of the two are connected to the opposite surface portions so as to cross each other, a vortex of the air that has flowed in as hot air is generated in the hot air box 2.

Moreover, since the corners of the inner surface of the hot air box 2 with which the axes of the hot air generators 3 and 3 abut are concave curved surfaces 32, 32, the flow of air that has become hot air and has flowed into the hot air box 2. Is very smooth.

The hot air outlet 1 formed in the upper plate 7
Hot air is blown out stably and uniformly from 3, 13, ....

Substrate transfer means includes two belt conveyors 1.
4, 15 and a substrate transfer arm device 16.

The belt conveyor 14 is composed of two endless belts 14a, 14a arranged in parallel.
A and 14a are bridged over a pulley (not shown), and are rotated by motors 14b and 14b and a rotation transmission mechanism (not shown).

The belt conveyor 15 is also composed of two endless belts 15a, 15a arranged in parallel, and each belt 15a, 15a is spanned by a pulley (not shown) to rotate with a motor (15b, 15b) (not shown). It is designed to be rotated by a transmission mechanism.

The upper surfaces of the belts 14a, 14a, 15a, 15a of the belt conveyors 14, 15 are flush with the lower surfaces of the guide grooves 12, 12 of the guide rails 11, 11 provided on the upper surface of the hot air box 2. Is held in the position.

Reference numeral 17 denotes a support plate, which is a belt conveyor 1.
4, the hot air blowout unit 1, and the belt conveyor 15 are provided upright along one side of a substrate transfer path.

Reference numerals 18 and 18 denote pulleys rotatably supported at both ends of the surface of the support plate 17 facing the substrate transfer path side. An endless cord body 19 is laid over the pulleys 18 and 18. There is.

A drive pulley 20 is also rotatably supported on the surface of the support plate 17 on the substrate transfer path side, and is rotated by a motor 21. The lower portion of the cord body 19 is wound around the drive pulley 20 for about two turns.

When the motor 21 rotates, the cord body 19 is moved. A moving base 22 is connected to the cord body 19. Reference numeral 23 is a sliding piece projecting from an end surface of the moving base 22 facing the supporting plate 17, and the sliding piece 23 is slidably engaged with a guide groove (not shown) formed in the supporting plate 17. ing.

Therefore, the motor 21 is rotated and the cord 19
When M moves, the moving base 22 also moves.

Numerals 24 and 24 are columns which are erected from the upper surfaces of both ends of the movable base 22, and substrate transfer arms 25 and 25 are projected substantially horizontally from the surfaces of the columns 24 and 24 on the substrate transfer path side. Has been.

The tip ends of the substrate transfer arms 25, 25 are located at intermediate positions between the belts 14a and 14a (belts 15a and 15a).
It is also an intermediate position between the guide rails 11 and 11. ), And support pieces 25a, 25a are formed projecting downward from there.

Then, such a substrate transfer arm 25,
25 is configured to move in the vertical direction along the columns 24, 24 by a drive mechanism (not shown).

Reference numeral 26 is a substrate.

Reference numeral 27 is a chip component arranged on the substrate 26, and cream solders 28, 28 are applied between its terminal portions 27a, 27a and lands (not shown) on the substrate 26.

Reference numeral 29 is a lead component, and the lead 29
a and 29a are penetrated through cream solders 28 and 28 applied to holes (not shown) provided on the substrate 26 and lands (not shown) provided on the lower surface of the substrate 26.

However, as described above, the cream solder 2
8, 28, ... Are applied and the chip parts 27,
The board 26 on which the lead parts 29 are arranged is conveyed toward the hot air box 2 by the belt conveyor 14, and both side edges of the leading end portion in the conveying direction are formed on the guide rails 11 and 11 of the hot air blowing portion 1. The guide grooves 12, 12 are inserted.

Then, the substrate transfer arms 25, 25 that have been raised upward are lowered, and the supporting pieces 25a, 25a come close to the front edge and the rear edge of the substrate 26.

Then, when the motor 21 rotates and the moving base 22 moves, the rear edge of the substrate 26 is pressed by the support piece 25a of the substrate transfer arm 25, and the guide grooves 12, 12 of the guide rails 11, 11 are moved. While being guided by the hot-air box 2, the hot-air box 2 passes through the place where the hot-air blowing holes 13, 13, ... Are formed.

Then, when the board 26 is moved on the hot air box 2, the cream solder 28, 2 applied to the board 26 is moved.
.. are reflowed by the hot air blown out stably and uniformly from the hot air blowing holes 13, 13.

When most of the substrate 26 that has passed over the hot air box 2 is placed on the belt conveyor 15, the substrate transfer arm 2
5, 25 move up and the moving base 22 returns to the original position. Then, the substrate 26 is carried out by the belt conveyor 15.

Reference numeral 30 is a cooling fan disposed between the belts 15a and 15a at the carrying end of the belt conveyor 15, and the substrate 26 carried to the carrying end of the belt conveyor 15 is cooled by the cooling fan 30. Will be.

[0048]

As is apparent from the above description, the hot air box with reflow solder of the present invention has a box shape in which one side is opened, and a plate having a plurality of hot air blowing holes is formed to cover the opening. In the reflow soldering hot air box having a hot air generator having one end connected to an air compressor and the other end connected to the box and a hot air heater attached along the way, Is characterized in that it is connected to the opposite surface of the box such that the axes of the boxes are offset from each other.

Therefore, according to the hot air box with reflow soldering according to the present invention, since the parts are soldered at the position separated from the hot air box, the soldering of the lead parts, especially the lead parts and the chip parts are mixed. Simultaneous soldering or spot-like soldering is possible, and not only is it possible to solder parts that are weak to heat, but it also creates a swirl of the air that has flowed in as hot air in the hot air box. Therefore, it is possible to stabilize and uniformly blow out hot air from the plurality of hot air outlets.

[Brief description of drawings]

1 shows an embodiment of a hot air box with reflow soldering according to the present invention together with FIGS. 2 to 6, and is a plan view of the whole.

FIG. 2 is an enlarged cross-sectional view taken along the line II-II of FIG.

FIG. 3 is a view in which the board is inserted into the rail.
FIG. 3 is an enlarged sectional view taken along line III-III of FIG.

FIG. 4 is a partially cutaway plan view of a hot air blowing portion.

FIG. 5 is a partially cutaway side view of a hot air blowing portion.

FIG. 6 is a partially cutaway perspective view of the hot air generator.

[Explanation of symbols]

 1 Hot Air Blowing Part 2 Hot Air Box 3 Hot Air Generator 7 Plate (Upper Plate) 10 Heater (Heater Element) 13 Hot Air Blowing Hole, 31 Air Compressor 32 Concave Curved Surface

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yu Tanijima 1300, Bonson Electronics Co., Ltd., Sakado, Saitama Prefecture (72) Inventor Harutaka Hayasaka 1300, Tsukagoshi, Sakado, Saitama Prefecture (72) Inventor, Toru Arai 1300 Bonson Electronics Co., Ltd., Sakado City, Saitama Prefecture (72) Inventor Hitoshi Terada 1300 Tsukakoshi, Sakado City, Saitama Prefecture

Claims (2)

[Claims] 1. A box-shaped plate having one opening, and a plate having a plurality of hot-air blowing holes arranged so as to cover the opening,
In a hot air box with reflow solder, one end of which is connected to an air compressor and the other end of which is connected to the box to generate hot air by a heater attached midway, in which the hot air generator is the opposite side of the box. A hot-air box with reflow solder, characterized in that the axes of the two are connected to each other so that they do not match each other. 2. The hot air box with reflow soldering according to claim 1, wherein a corner of the inner surface of the hot air box where the axis of the hot air generator abuts is formed as a concave curved surface.