JPH0362590A - Substrate heating equipment - Google Patents

Abstract

PURPOSE:To heat electronic parts on a substrate without thermal shock, by installing a hot air jetting parts in the vicinity of end portions on both of the facing sides of substrates on a vertical substrate conveying part, and installing hot air exhausting parts in the vicinity of the end portions on both sides in the rectangular direction. CONSTITUTION:Substrates P mounted on a vertical substrate conveying part 31 are stopped for a specified period in the couese of ascending, and heated by blowing hot air against the substrates P from hot air jetting parts 32, 33 installed in the vicinity of the end portions on both of the facing sides of the substrates P. The hot air is discharged from hot air exhausting parts 34, 35 installed on the end portions on both sides in the rectangular direction of the substrate P. Then the heating is repeated in the same manner.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention is suitable for soldering electronic components to a printed circuit board (hereinafter referred to as the board) by a vertical transport method, or using a flow soldering device or the like. The present invention relates to a substrate heating device to be used.

BACKGROUND OF THE INVENTION A conventional board heating apparatus will be described using a flow soldering apparatus as an example, in which electronic parts are soldered to a board by heating a board on which electronic parts are mounted on cream solder.

Figure 5 is a schematic front view of a conventional glue flow soldering device;
The figure is a schematic side view of a main part of a vertical substrate conveying section that is applied to a preheating section of the reflow soldering apparatus, and FIG. 7 is a schematic perspective view of a heating device in the preheating section of the reflow soldering apparatus. First of all, the fifth
The outline of the substrate conveyance method and heating method is shown in FIG. 6 and FIG.

As shown in FIGS. 5 and 6, the entrance 1 of the preheating section 1
A substrate P#i carried in in the direction of the arrow from a, a pair of left and right endless chains 2a b and 2b and 3a b and 3b provided front and rear as viewed from the direction of the arrow in the substrate vertical conveyance section 1b disposed in the preheating section. The board support attached to the board moves upward with the end of the board supported by the parts 4aj> and 4b. The endless chains 2a, 2b and 3a, 3b are driven by rotating a shaft 7 to which bevel gears 6a and 6b are attached using a power source 5, so that the bevel gears 8a and 8b integrated with the pulley rotate at a 90 degree angle. (turns and rotates, bell)
9a> and 9b. When the substrate P moves upward, the preheating chamber 10 substrate holder is in the parts 4a and 4b.
It is preheated by hot air blown out from heating devices 10 and 11 installed facing each other in the front and rear. By the pusher 13 sliding along the
It is equipped with far-infrared panel heaters 14a to 14b and a hot air blowing nozzle 15, and is transported to a flow section 16 for soldering. Inside, the pusher 13 is the front and rear slider locket) 17a:! ? and 17b, and is fixed to a chain 18, and driving is provided by a drive source 19 to which a sprocket 17b is attached. Next, after soldering, the board P is placed in a cooling unit 21, which is a vertical conveyance type cooling unit 2G having the same mechanism as the preheating unit 1.
Cool down. When the substrate P reaches the bottom of the vertical conveyance section 20!1, it is pushed out from the outlet 20b by the pusher 23 attached to the tip of the air cylinder n and carried out to the outside.

Next, the heating device 10.11 in the preheating section 1 having the substrate vertical transfer section 1b will be explained. As shown in FIGS. 7 to 9, the substrate P carried into the lowest part of the substrate vertical conveyance section 1b is first blown with hot air from the hot air outlet 10a of the heating device 10, and is heated from the right end of the substrate P. , the hot air is discharged through the hot air exhaust port 11a of the opposing heating device 11. After the substrate P stops for a certain period of time, it rises for a certain period, and conversely, hot air is blown from the hot air outlet 11b of the heating device 11, and the substrate P is heated from the left end.
The hot air is discharged through the hot air exhaust port 10b of the heating device 10.

After that, the substrate P rises in the same way as the hot air outlet 10c.
The substrate P is heated from the right end by the hot air from the heating device 11, and then heated from the left end by the hot air from the hot air outlet lid of the heating device 11. FIG. 10 shows the temperature profile at points Pa> and Pb on the substrate P shown in FIG. 8 at this time. The temperature profile i is that of a point Pa on the substrate P, and when the substrate P moves upward from the hot air outlet 10b to the hot air outlet 10c of the heating device 10, the temperature increase rate increases, and the boundary point is It is tl. Further, the temperature profile H is for a point Pb on the substrate P, and when the substrate P moves upward from the hot air outlet 11m of the heating device 11 to the hot air outlet 11b, the temperature increase rate increases, and the boundary point is t2, and also when the hot air outlet lid moves upward from the hot air outlet 11c, the rising speed increases, and the boundary point thereof is t3.

Problems to be Solved by the Invention However, in this type of substrate heating apparatus having a vertical conveyance method, as shown in the temperature profile in FIG. Because it is difficult for the edges of the board to rise in temperature, there is a problem in that thermal shock may be applied to electronic components mounted on the board.

The present invention solves the above-mentioned problems, and aims to provide a substrate heating device that has small fluctuations in temperature increase rate at both ends of the substrate and does not cause thermal shock to electronic components mounted on the substrate. It is something to do.

Means for Solving the Problems In order to solve the above problems, the substrate heating device of the present invention includes:
A hot air blowing section is provided in close proximity to both opposing ends of the substrate of the substrate vertical conveyance section, and the hot air blowing section is provided on both opposing sides in a direction perpendicular to the opposite ends of the substrate where the hot air blowing section is provided. A hot air exhaust section is disposed close to each end.

Effect With the above configuration, hot air can be blown onto the board from both ends, which reduces the variation in the rate of temperature rise applied to both ends of the board, and also eliminates the need for the hot air blowing section and hot air exhaust section of conventional equipment. There is no sudden change in the rate of temperature rise that occurs at the boundary, and there is no thermal shock to electronic components mounted on the board.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings. Among these, the board heating device of this embodiment heats a board on which electronic components are mounted on cream solder as shown in FIG. Substrate P in substrate vertical transport section 1b of section l
This is an example in which the substrate heating device is provided in place of the heating device 10.11 provided in the vicinity of the substrate heating device, and only the substrate heating device will be described below, and a description of other parts of the reflow soldering device will be omitted.

FIG. 1 is a schematic perspective view of a substrate heating apparatus according to an embodiment of the present invention, FIG. 2 is a schematic plan view of the same substrate heating apparatus, and FIG. 3 is a schematic front view of the same substrate heating apparatus. As shown in FIGS. 1 to 3, hot air blowing units 32 and 33 are located close to opposite ends of the substrate P to be hung on the substrate vertical conveyance unit 31, respectively.
and the board P provided with the hot air blowing parts 32 and 33.
Hot air exhaust portions 34 and 35 are respectively disposed close to opposite end portions in a direction perpendicular to both end portions.

In the substrate heating apparatus of this embodiment, the substrate vertical transport section 31
The substrate P carried into the lowest part of the board P is heated by hot air blowing hot air from the lowest hot air outlets 32a and 33a of the opposing hot air blowing units 32 and 33 provided at the ends of both sides.
The hot air is discharged from hot air exhaust sections 34 and 35, which are disposed opposite to each other at both ends in the direction of the small groups 32 and 33. Board P/f
i After stopping for a certain period of time, it rises for a certain period of time and blows hot air through the hot air outlets 32b and 33b, and the hot air is discharged through the hot air exhaust section 34 and the deaf. After that, the board P rises in the same way, and the hot air blowing part 32c
> and 33c, hot air blowing section 32d 'J? and 33d
Hot air is blown from both ends of the board to heat it.

At this time, the temperature props applied to points PA> and PB on both ends of the substrate P are sprayed under the same conditions, so they draw almost the same external temperature curve. In this way, there was little variation in the temperature increase rate between both ends of the substrate P, and there were no sudden fluctuations, and it was possible to heat the electronic components mounted on the substrate P without giving them thermal shock.

Effects of the Invention As described above, the substrate heating device of the present invention is a substrate heating device equipped with a vertical substrate conveying section, and is capable of blowing hot air from both ends of the substrate. In addition, since there is no sudden change in the temperature increase rate at the boundary between the hot air blowing section and the heat/air exhaust section, the temperature increase rate can be reduced. No thermal shock is applied to the parts, and no electronic parts are damaged.

[Brief explanation of drawings]

1 is a schematic perspective view of a substrate heating device according to an embodiment of the present invention, FIG. 2 is a schematic plan view of the same substrate heating device, FIG. 3 is a schematic front view of the same substrate heating device, and FIG. 4 is a schematic front view of the same substrate heating device. A temperature profile diagram of both ends of the board heated by the board heating device, Figure 5 is a schematic front view of the conventional glue-flow soldering equipment, and Figure 6 shows the main points of the vertical substrate conveyance section that is applied to the preheating part of the reflow soldering equipment. 7 is a schematic perspective view of the heating device in the preheating section of the reflow soldering apparatus, FIG. 8 is a schematic plan view of the heating device, and FIG. 9 is a schematic front view of the heating device. , 10th
The figure is a temperature profile diagram of both ends of the substrate heated by the same heating device. 31... Board vertical transfer section, 32.33... Hot air blowing section, fox. Word... Hot air exhaust section, P... Board.

Claims (1)

[Claims] 1. A board vertical transport unit that transports at least one printed circuit board on which electronic components are mounted in a vertical direction while keeping the board surface horizontal and maintaining a predetermined interval; A hot air blowing section is provided in proximity to each of the substrates, and a hot air exhausting section is provided in proximity to both opposing ends of the substrate in a direction orthogonal to the ends on both sides of the substrate provided with the hot air blowing sections. A substrate heating device characterized by: