JPH0719955B2 - Reflow soldering equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflow soldering apparatus, and in particular, a longitudinal direction of tubular heaters provided above and below a substrate transfer device is arranged so as to match the substrate transfer direction. In addition, the present invention relates to a reflow soldering device which is provided with an air blower that agitates heated air in a heating chamber while performing a swinging motion to efficiently heat and solder a substrate with a small heater for power saving.

2. Description of the Related Art As a conventional reflow soldering device, a device in which tubular heaters are arranged with their longitudinal direction oriented in a direction perpendicular to the substrate transport direction has been put into practical use. On the other hand, it is difficult for the tubular heater to obtain uniform heating performance over its entire length, and the heating performance at both ends is inferior to that at the central part.

Therefore, in the conventional apparatus in which the longitudinal direction of the tubular heater is aligned with the direction perpendicular to the substrate transport direction, the side portions of the heating chamber are not sufficiently heated and only the central portion of the substrate is heated first. It was difficult to heat the substrate uniformly.

In addition, in order to uniformly heat the substrate, there is a drawback that a tubular heater that is long enough for the width of the substrate must be used so that it can be heated only at the central portion of the tubular heater with stable heating performance. As a result, there is a drawback that the soldering device becomes large. Further, the heat generated near both ends of the tubular heater cannot contribute much to the heating of the substrate, resulting in a waste of electric power.

Furthermore, the blower of the conventional device arranged in the heating chamber is
Since air was simply blown while it was fixed, sufficient air could not be sent to the corners or shades in the heating chamber, and uniform heating was not always possible, leaving room for improvement. Further, as a result, there is a problem that unevenness in soldering easily occurs depending on the position on the board.

The present invention has been made in order to eliminate the above-mentioned drawbacks of the prior art, and an object of the present invention is to make the longitudinal direction of a plurality of tubular heaters coincide with the substrate conveying direction and By arranging above and below, the heating characteristics in the direction perpendicular to the substrate transfer direction are made uniform over the entire width of the heating chamber, and by this, the entire surface of the substrate is heated uniformly and high-performance reflow soldering is performed. Is to be able to do.

In addition, another purpose is to make it possible to use all of the heat generated from the tubular heater for heating the substrate without wasting it and to perform soldering with the same performance as before the shortening even if the length of the tubular heater is shortened. And to reduce the size of the reflow soldering device. Another object is to provide a reflow soldering device that consumes less power and has a lower operating cost.

Still another object is to agitate the air in the heating chamber by causing the air blower installed in the heating chamber to perform a swinging motion, and to sufficiently blow the heated air to the corners and the shaded part. Is to be heated uniformly.

Configuration In summary, the present invention (Claim 1) includes a transfer device for transferring a substrate on which electronic components are loaded, and a plurality of heating chambers surrounding a plurality of tubular heaters arranged above and below the transfer device. In a reflow soldering device provided with a heating device provided, the longitudinal direction of the tubular heater is arranged so as to match the transport direction of the substrate. Further, the present invention (claim 2) is an electronic device. A transport device for transporting a substrate on which components are loaded, a plurality of tubular heaters arranged above and below the transport device and arranged with their longitudinal directions aligned with the transport direction of the substrate, and the tubular heater. A heating device in which a surrounding preheating chamber and a soldering chamber are arranged, and a swinging mechanism arranged in at least the preheating chamber of the heating device are provided, and a swinging motion is performed by the swinging mechanism. While adding It is characterized in that a blowing device for stirring the heated air in the room.

The present invention will be described below based on the embodiments shown in the drawings. A reflow soldering apparatus 1 according to the present invention, with reference to FIG. 1, is a substrate transfer apparatus 2, a tubular heater 3, and a heating chamber 4.
And a blower 5.

The board transfer device 2 is for loading and transferring a board 6, and a chain conveyor 8 is wound around a plurality of guide rollers 9 and a drive roller 10. The drive roller also has a first motor. Pulley 13 fixed to rotating shaft 12
The belt 14 wound around the substrate 6 is wound around and the rotational movement of the first motor 11 is transmitted to the chain conveyor 8 so that the substrate 6
Is configured to be conveyed in the direction of arrow A.

Below the transport device 2, a falling object discharge conveyor 15 is provided with a plurality of guide rollers 16 and drive rollers 18 as in the transport device 2.
Substrate, foreign matter, and the like that are wound around and are driven by the second motor 19 and dropped from the transport device 2 are loaded and transported.

The tubular heater 3 is for heating the substrate 6 from above and below, and its longitudinal direction is above and below the carrier device 2 with reference to FIGS. 2 and 3. They are arranged in a top-bottom pair so as to match (in the direction of arrow A). The pair of tubular heaters (four pairs of tubular heaters in this embodiment) are each surrounded by a heat insulating material 20 and are connected to each other by three preheating chambers 21 and one soldering chamber 22 connected to each other. The substrate 6 which is configured as the chamber 4 and which is transported by the transport device 2 is preheated sequentially in the three preheating chambers 21 and then further heated in the soldering chamber 22 to melt and solder the cream solder. It is configured.

The blower 5 is for agitating the heated air in the heating chamber 4 to make the inside of the heating chamber have a uniform temperature. In this embodiment, two types of blowers 5 are adopted. Second
The blower device 5 of the first type shown in the figure is a conventionally known blower device in which a blower motor 25 fixed to a machine frame 24 rotates a fan 28 fixed to a rotary shaft 26 in an upper portion 4a of the heating chamber. The air in the heating chamber 4 is pressure-fed from the upper side to the lower side to stir the heated air in the heating chamber.

The second type of blower device 5 is according to the present invention including the swing mechanism 23, and also referring to FIG. 4 and FIG.
A bearing 29 is fixed to the ceiling 4b of the heating chamber 4, and a swing shaft 30 is rotatably fitted in the bearing 29. A pulley 31 is fixed to an upper portion 30a of the swing shaft 30, and a pulley 34 fixed to an output shaft 33a to which rotational movement is transmitted from a swing motor 32 fixed to the machine frame 24 via a reduction gear 33. The belt 35 is wound around the fan 35 and the fan 42 is rotated by the swing motor 32 in the direction of FIG. 5B. A hollow ring 3 is attached to the lower part 30b of the swing shaft 30.
0c is fixed, and the direction of the axis of the ring is the swing axis.
The through holes 30d of 30 are inclined by, for example, 15 °. Further, the ring 30c has a holding plate 30e for holding the bearing 36 on its axis.
Is fixed.

The rotary shaft 26 of the blower motor 25 fixed to the machine frame 24 is connected to the first rotary shaft 38 rotatably fitted in the through hole 30d of the swing shaft 30 by the coupler 39, and also the first rotary shaft 38. Rotating shaft 38
Is a second joint that is rotatably fitted to the bearing 36 by a universal joint 40.
Of the blower motor 25 is transmitted to the second rotary shaft 41 through the universal joint 40, and the second rotary shaft 41 is connected to the second rotary shaft 41.
The fan 42 fixed to the tip of the rotating shaft of the
Air is pumped downward from above in the direction of arrow C in the figure.

Further, the reflow soldering apparatus 1 has an exhaust fan 43 for exhausting gas, smoke, etc. generated during soldering, a cooling fan 44 for cooling the soldered board 6, and a width of the board 6. The chain width adjusting device 45 for adjusting the effective width of the carrying device 2 is provided, but the description thereof will be omitted because they are known devices.

Action The present invention is configured as described above, and its action will be described below. As shown in FIG.
When inserted into a, the chain conveyor 8 conveys it in the direction of arrow A, and tubular heaters arranged above and below the conveying device 2 in the _first heating zone H ₁ of the preheating chamber 21 move the substrate 6 upward and downward. When heated from below, the simultaneous fan 28 is rotationally driven by the blower motor 25, and the air heated by the tubular heater is pressure-fed downward from above to agitate in the preheating chamber 21 to adjust the temperature in the preheating chamber. By making it uniform, the substrate 6 is heated uniformly.

The substrate 6 heated in the first heating zone H ₁ is further conveyed and is heated to a predetermined temperature (eg 150 ° C.) in the heating zones H ₂ and H _3.
C.) and then transferred to the soldering chamber 22.
Then, after being heated to a melting temperature (for example, 250 ° C.) or higher of the cream solder by the tubular heater 3 to be soldered, it is cooled by the cooling fan 44 and taken out from the carry-out port 24b.

Here, the heating action in the heating chamber 4 will be described with reference to FIGS. 3 to 5 as well. The tubular heaters 3 arranged in the heating chamber 4 are arranged with their longitudinal directions aligned with the transport direction of the substrate 6, so that the transport direction of the substrate 6 (arrow A
The temperature in the direction perpendicular to the (direction) is constant everywhere, and the temperature of the side portion 4c of the heating chamber does not become low unlike the conventional reflow soldering apparatus. It is uniformly heated by the radiant heat of the above, and only a part such as the central portion does not become abnormally high temperature. Further, since the temperature distribution in the direction perpendicular to the transport direction is constant, it is possible to uniformly heat the substrate 6 having the width L of the tubular heater 3 (width 1) in FIG. In the conventional device, the width of the heating chamber 4 hits 40% of the width of the central part, which is lower than the temperature in the central part, and the left and right end regions, which cannot be used, can be used, and the device can be downsized. It is possible to eliminate the electric power wasted in the both ends.

Further, in the blower device 5, the rotational movement of the blower motor 25 is transmitted to the first rotary shaft 38, and further transmitted via the universal joint 40 to the second rotary shaft 41 and the fan 42 which are pivotally supported by the bearing 36. The fan 42 is rotated in the direction of arrow C to feed the heated air in the heating chamber 4 from above to below, and at the same time, the swing motor 32
Since the rotating motion is also reduced by, for example, 1/20 by the reduction gear 33, the pulley 34, the belt 35, and the pulley 31 are rotated.
The swing shaft 30 which is transmitted to the bearing 29 and is supported by the bearing 29 is slowly rotated in the direction of arrow B. As a result, the fan 42 revolves in the direction of the arrow B while rotating in the direction of the arrow C, so that the flow of the air pumped by the fan 42 changes its direction along an arc and changes from the direction of the arrow D to the direction of E. ,
Further, since the heated air in the heating chamber 4 is thoroughly stirred while changing the direction to the F direction, the temperature in the heating chamber 4 becomes substantially uniform everywhere.

Effects As described above, according to the present invention, since the longitudinal direction of the plurality of tubular heaters is aligned above and below the substrate transfer device with the longitudinal direction thereof aligned with the substrate transfer direction, the heating characteristics in the direction perpendicular to the substrate transfer direction are heated. The effect is that it can be made uniform over the entire width of the chamber. Further, as a result, there is an effect that the entire surface of the substrate is uniformly heated and high-performance reflow soldering can be performed. Furthermore, since the heat generated from the tubular heater can be utilized for heating the substrate without being wasted, the length of the tubular heater can be shortened and the reflow soldering device can be downsized. Further, there is an effect that it is possible to provide a reflow soldering device which consumes less electric power and has a low exercise cost.

Further, since the blower installed in the heating chamber is provided with a swinging mechanism so that the swinging motion is performed, the air in the heating chamber is agitated to sufficiently heat the corners and the shaded part. There is an effect that the substrate can be uniformly heated by blowing air.

[Brief description of drawings]

1 is a front view showing the entire reflow soldering apparatus, FIG. 2 is a vertical sectional view of a heating chamber, and FIG. 3 is a plan view showing a positional relationship between a tubular heater and a substrate. FIG. 4 is an enlarged vertical sectional view of an essential part showing the blower, and FIG. 5 is a perspective view showing the blower. 1 is a reflow soldering device, 2 is a conveying device, 3 is a tubular heater, 4 is a heating chamber, 5 is a blowing device, 6 is a substrate, 21 is a preheating chamber, 22 is a soldering chamber, and 23 is a swing mechanism. .

Claims (2)

[Claims] 1. A transport device for transporting a substrate on which electronic components are loaded, and a heating device having a plurality of heating chambers surrounding a plurality of tubular heaters disposed above and below the transport device. In the reflow soldering device, the tubular heaters are arranged such that the longitudinal direction of the tubular heaters is aligned with the conveyance direction of the substrate. 2. A transport device for transporting a substrate on which electronic components are loaded, and a plurality of tubular heaters arranged above and below the transport device and arranged such that their longitudinal directions are aligned with the transport direction of the substrate. A heating device having a preheating chamber surrounding the tubular heater and a soldering chamber, and a swinging mechanism provided in at least the preheating chamber of the heating device. A reflow soldering device, comprising: a blower for stirring the heated air in the heating chamber while performing a swing motion.