KR20060026719A - A cooling ejector for reflow solder machine - Google Patents

Abstract

In the present invention, when providing the outside air to the substrate to be transferred to the cooling zone, by using the compressed air generated in the compressor forcibly sucked the outside air to increase the flow rate of the air more than the amount of air actually introduced from the outside The cooling apparatus of the reflow solder machine that can inject the cooling air of the substrate to increase the cooling efficiency.

According to an embodiment of the present invention, at least one or more air cooling holes are installed on an upper portion of a cooling zone of a solder machine main body for cooling a substrate, and compressed air inflow holes are formed in a direction orthogonal to the air injection holes. Cooling ejector for ejecting to the substrate by increasing the flow rate of the outside air flowing in the air blowing direction through the compressed air; And a compressor for generating compressed air and providing the cooling ejector to the cooling ejector.

Reflow Solder Machine, Cooling Ejector, Housing, Compressed Air, Compressor, Pressure Reducing Valve

Description

Cooling device for reflow solder machine {A cooling ejector for reflow solder machine}             

1 is a perspective view showing the configuration of a typical reflow solder machine.

Figure 2 is a schematic diagram showing the configuration of a cooling apparatus using a turbo blower as an example of the reflow solder machine cooling apparatus according to the prior art.

Figure 3 is a schematic diagram showing the configuration of a cooling apparatus using a small fan, as another example of the reflow solder machine cooling apparatus according to the prior art.

Figure 4 is a schematic diagram showing an embodiment of a reflow solder machine cooling apparatus according to the present invention.

5 is a sectional view showing a detailed configuration of a cooling ejector which is a main part of the present invention.

6 is an exploded cross-sectional view of FIG.

<Description of the symbols for the main parts of the drawings>

1: solder machine body 2: cooling zone

3: support plate 4: support

5: cooling ejector 6: compressor

7: pressure reducing valve 11: housing

12: ejector body 13: O-ring

The present invention relates to a cooling apparatus for cooling a heated substrate and components after soldering is completed in a reflow soldering machine. More particularly, the present invention provides compressed air to cooling air sucked from the outside to provide a large amount of cooling air. The present invention relates to a reflow soldering machine cooling apparatus capable of increasing cooling efficiency by blowing air to a substrate at an angle.

Recently, electronic products have been developed into miniaturization, light weight, and high functionality, and research on the reliability of minute joints is continuously pursued due to the miniaturization of packages. However, even when semiconductor devices and electronic products are miniaturized, miniaturization of devices is impossible unless a bonding technology such as micro soldering, which is the connection technology, is established. In order to meet these miniaturization and economic needs, surface mount technology (SMT) of electronic products has been promoted.

In general, a reflow soldering machine is a chip mounter in a surface mounting technology (SMT) production line for mounting small electronic components such as a semiconductor chip or a resistance chip of a printed circuit board (PCB). Chip Mounter is one of the important equipments to determine the quality of the final electronic product produced by the chip mounter, the solder solder under the electronic component by the ultra-uniform heating of the electronic component placed on the PCB substrate It is a device for fixing the electronic component on the PCB through the cooling process after melting (cream solder) or solder paste (solder paste). In particular, the reflow soldering machine is widely used when soldering small components that are weak to heat. The reflow soldering technology for heating, cooling, and fixing without internal and external damages ultimately determines the quality of electronic products. The reflow soldering system, along with the chip mounter, forms two major axes of the surface mount (SMT) production line.

As shown in FIG. 1, the reflow solder machine includes a PC control unit 110, a transfer unit 120, a multi heating zone including a plurality of heating zones and a reflow zone. 130, a cooling zone 140, an exhaust part, and the like.

Looking at the solder process using the reflow solder machine consisting of the above configuration as follows.

First, a cream solder or solder paste is printed and a PCB on which a plurality of parts are disposed is supplied to the transfer unit 120 by a work command of the PC controller 110. At this time, the width of the PCB is sensed by the PCB sensor formed on the inlet side of the transfer unit 120 automatically adjusts the conveyor width of the transfer unit 120 and then the PCB is introduced, by the conveyor of the transfer unit 120 As the PCB is transferred in one direction, preheating and heating are performed to a melting point temperature of a lead free solder by a plurality of the heating zones. Then, the PCB is heated to a melting temperature higher than the melting point temperature while passing through the reflow zone to solder a plurality of electronic components disposed on the PCB. Thereafter, the PCB passes through the exhaust portion, and the flux carbonization gas generated by the melting of the lead-free solder is recovered and discharged. The lead-free solder is solidified while passing through the cooling zone 140 and the multi-heating zone and the ripple. PCB is soldered by a series of processes in which the PCB heated by the lower zone cools and flows out.

The multi-heating zone 130 is divided into 4 to 8 heating zones and 1 to 2 reflow zones during the lead free soldering operation of BGA, CSP, multilayer boards, etc. It provides a temperature profile, and the multi-heating is performed by forced convection in five directions of front, rear, left and right by a multi-jet nozzle and a twin fan installed therein, so that ultra-uniform heating is performed.

A conventional method for cooling a substrate discharged after solder completion in a series of processes by the reflow solder machine will be briefly described with reference to FIGS. 2 and 3.

First, Figure 2 shows a cooling method of the substrate using a turbo blower, as shown in the figure, when the turbo blower 201 is installed and operated on the outlet side of the main body, the fan attached to its motor shaft is As it rotates, it takes in air from the atmosphere. The intake air is filtered through a filter built in the turbo blower 201, and then flows into a freshly shaped inlet plate 202 connected to the turbo blower 201 through a pipe 203. In addition, the cooling air is ejected from the inlet plate 202 to cool the substrate and the component.

3 shows a cooling method of a substrate using a plurality of small fans, and as shown in the drawing, a plurality of small fans 301 are installed and operated at an outlet side of the main body to intake external air to directly induce air to the substrate side. It is a method of spraying.

The cooling temperature by these injection methods is about 150 ° C.

In the cooling method using the electronic turbo blower having the above-described configuration, the intake plate is formed in the shape of a lampshade, so that the blowing angle of spraying is constant, and thus there is a problem in that there is a limit in cooling the substrate widely. In addition, the amount of air is not controlled because the external cooling air is sucked and ejected by the intake method, and the cooling efficiency is lowered because the substrate and the components are cooled by the blowing of constant intensity.

The cooling method using the latter small fan, like the cooling method using the former turbo blower, can not control the air volume, and still has a problem in that there is a limit in lowering the cooling temperature because it is injected by the blowing of constant intensity.

Therefore, the present invention has been proposed to solve the above problems, when cooling the substrate to be transferred to the cooling zone with the outside air, by using the compressed air generated in the compressor to force the outside air to increase the flow rate of the air By spraying about 6 to 10 times more cooling air on the substrate than the amount of air that is naturally introduced from the outside, the substrate is cooled to a lower temperature (about 100) or less before being discharged to the outside of the reflow soldering machine. It is an object of the present invention to provide a cooling device of a reflow solder machine that can increase the cooling efficiency.

In addition, another object of the present invention is to provide a cooling device of a reflow solder machine that can be injected while adjusting the air volume according to the characteristics of the substrate to be cooled by installing a pressure reducing valve in the compressor for providing compressed air.

In order to achieve the above object, the present invention, at least one or more installed in the cooling zone of the main body of the solder machine for cooling the substrate, the air injection hole for injecting cooling air to the substrate, and in the direction perpendicular to the air injection hole A cooling ejector having a compressed air inlet hole formed therein to increase the flow rate of the external air flowing in the air ejecting direction through the compressed air and ejecting the compressed air to the substrate; And a compressor for generating compressed air and providing the cooling ejector to the cooling ejector.

In addition, the present invention further comprises a decompression means for controlling the amount of compressed air provided between the cooling ejector and the compressor provided to the cooling ejector from the compressor. The pressure reducing means is provided to vary the air volume according to the characteristics of the substrate.

The cooling ejector may include a housing having a through hole for passing outside air therethrough in an axial direction, and an injection hole for injecting compressed air in a direction orthogonal to the through hole; And an ejector body inserted into an inner space of the housing and communicating with a through hole thereof, and having a guide groove formed on an outer circumferential surface corresponding to an injection hole of the housing to guide compressed air to an air injection hole. And a portion where the inner surface of the through hole of the housing and the air injection hole of the ejector body are spaced apart by a predetermined interval so that compressed air flows out through the guide groove to form a gap.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings of FIGS. 4 to 6.

The reflow solder machine cooling apparatus according to the present invention increases the flow rate of the cooling air sucked from the outside by using compressed air to increase the cooling efficiency by injecting a large amount of air at a wide angle than the suction amount by the natural flow rate. In the embodiment of the present invention, as shown in Figure 4, the support plate (3) provided on the upper portion of the cooling zone (2) provided on the outlet side of the solder machine body (1); A cooling ejector (5) installed at least one or more with a predetermined inclination on the support plate (3); A support (4) installed on the support plate (3) and supporting the cooling ejector (5) at a predetermined inclination angle; A compressor (6) connected to the cooling ejector (5) for providing compressed air thereto; And a pressure reducing valve (7) installed between the cooling ejector (5) and the compressor (6) for adjusting the amount of compressed air provided from the compressor (6).

Here, the cooling ejector 5 is fitted into the housing 11 into which the outside air naturally flows, as shown in FIGS. 5 and 6, and the inner space of the housing 11, and the cooling air cooling zone ( It consists of an ejector body 12 that sprays on 2).

The housing 11 includes a through hole 11a tapered from the outside to the inside at a predetermined section at one end to secure and pass a larger amount of external air; It is formed on the outer circumferential surface of the direction orthogonal to the through hole 11a and has an injection hole 11b for injecting compressed air. In addition, a flange 11c for fixing to the support 4 is formed at the other end of the housing 11.

The ejector body 12 is inserted into the inner space of the housing 11 to communicate with the through-hole 11a of the housing 11, the air injection hole 12a having a tapered portion extending from the inlet side of the intake air to the outlet side )and; It is formed on the outer peripheral surface corresponding to the injection hole (11b) of the housing 11 has a guide groove (12b) for guiding the compressed air to the air injection hole (12a) side.

In addition, the outer peripheral surface of the ejector body 12 is provided with an O-ring 13 for maintaining the airtightness with the inner surface of the housing (11). The O-ring 13 is located below the guide groove 12b to prevent leakage of compressed air.

In this embodiment, a portion of the housing 11 in contact with the through-hole 11a and the air injection hole 12a of the ejector body 12 is spaced apart by a predetermined interval to eject the compressed air toward the air injection hole 12a. Gaps are formed. The gap is to allow the compressed air injected through the injection hole (11b) to escape while rotating the guide groove (12b), the compressed air exited through the gap to accelerate the flow rate of the suction air.

Referring to the working state of the present invention configured as described above are as follows.

When the PCB having a plurality of parts mounted thereon is soldered in the heating zone of the solder machine main body 1 and then transferred to the cooling zone 2, the compressor 6 is operated to provide compressed air to the cooling ejector 5. Will be supplied. In FIG. 5, for convenience, one compressor 6 is shown to provide air to the cooling ejector 5, but this is merely for convenience of illustration, and preferably one compressor 6 is 1 to 1. Air is supplied to six cooling ejectors (5).

 In the cooling ejector 5, the compressed air is sent to the guide groove 12b of the ejector body 12 through the injection hole 11b of the housing 11. Since the compressed air injected into the guide groove 12b is in a state higher than the outside air pressure, a pressure difference is formed, and the guide groove 12b rotates through the gap while rapidly flowing out to the through hole 12a. . When the compressed air flows out of the gap while rotating in the guide groove 12b, the compressed air hits the inner wall surface of the through hole 11a, and the outflow direction of the compressed air is directed toward the air injection hole 12b. ) Forced suction of ambient air around them.

The suction zone of the outside air sucked into the through-hole 11a by the high-pressure compressed air rapidly flowing out through the gap is increased, thereby cooling the cooling zone 2 through the air injection hole 12a formed to taper a large amount of air. Squirts). Here, the amount of air discharged through the ejector is increased by about 6 to 10 times the amount of air sucked into the ejector. Accordingly, the substrate can be lowered to a low temperature of 100 ° C. or less before being discharged to the outside of the reflow solder machine.

In the spraying process, by adjusting the opening and closing angle of the pressure reducing valve according to the characteristics of the substrate is provided to the substrate in a state in which the air flow is adjusted, the air injection hole (12a) is formed to be tapered so that the intake air with the help of compressed air When ejected quickly, the injection angle is widened to increase the air contact area of the substrate, thereby improving the cooling efficiency.

As described above, according to the present invention, by using the compressed air generated in the compressor to accelerate the flow rate of the cooling air naturally introduced from the outside, the amount of air to be transferred to the cooling zone 6 to 10 times more than the cooling air introduced naturally. In addition to directly spraying onto the substrate, the internal diameter of the cooling ejector forms a tapered structure that extends from the air inlet toward the outlet, thereby increasing the blowing angle of the cooling air, thereby increasing the air contact area of the substrate. Therefore, it is possible to cool the temperature of the substrate to a low temperature of about 100 ° C. or less, that is, to increase the cooling efficiency.

In addition, the present invention has another effect of varying the degree of cooling according to the characteristics of the substrate by adjusting the air flow rate using a pressure reducing valve.

Compared to the cooling method of the substrate using the conventional turbo blower shown in FIG. 2 and the cooling method of the substrate using a plurality of conventional small fans shown in FIG. 3, it is clear that the effect of the present invention is very excellent. Become. In other words, the temperature of the substrate cooled by the conventional cooling method of the substrate is about 150 ℃, while the temperature of the substrate cooled according to the present invention can be cooled to 100 ℃ or less. In addition, in the conventional cooling method, the blowing amount cannot be adjusted, so that cooling efficiency is lowered. In the cooling method according to the present invention, the blowing amount can be adjusted according to the characteristics of the substrate.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, modifications, and changes are possible within the scope without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

Claims (7)

At least one or more cooling zones are installed on the upper side of the cooling zone of the solder machine body for cooling the substrate, and compressed air inflow holes are formed in a direction orthogonal to the air injection holes. Cooling ejector for ejecting to the substrate by increasing the flow rate of the outside air flowing in the air blowing direction by a medium; And Compressor that generates compressed air and provides it to the cooling ejector Cooling device of the reflow solder machine comprising a. The method of claim 1, And a pressure reducing means installed between the cooling ejector and the compressor to adjust an amount of compressed air provided from the compressor to the cooling ejector. The method according to claim 1 or 2, The cooling ejector A housing having a through hole for passing outside air in an axial direction and having an injection hole for injecting compressed air in a direction orthogonal to the through hole; And An ejector body having an air injection hole inserted into an inner space of the housing and communicating with a through hole thereof, and a guide groove formed on an outer circumferential surface corresponding to the injection hole of the housing to guide compressed air to the air injection hole; Cooling device of the reflow solder machine comprising a. The method of claim 3, wherein Cooling apparatus of the reflow solder machine characterized in that the space between the inner surface of the through-hole of the housing and the air injection hole of the ejector body is spaced apart by a predetermined interval so that the compressed air flows through the guide groove. The method of claim 3, wherein Cooling apparatus of the reflow solder machine is installed on the outer circumferential surface of the ejector body further comprises an O hermetic holding means for maintaining airtightness with the inner surface of the housing. The method of claim 4, wherein The through hole of the housing is formed in a predetermined section of one end thereof, and is tapered from the outside to the inside to secure and pass a larger amount of external air. Cooling apparatus of the reflow solder machine, characterized in that the air injection hole of the ejector body is tapered so that the inner diameter extends from the inlet side to the outlet side of the intake air. At least one or more cooling zones are installed on the upper side of the cooling zone of the solder machine body for cooling the substrate, and compressed air inflow holes are formed in a direction orthogonal to the air injection holes. Cooling ejector for ejecting to the substrate by increasing the flow rate of the outside air flowing in the air blowing direction by a medium; A compressor for generating compressed air and providing it to the cooling ejector; And Pressure reducing means installed between the cooling ejector and the compressor, for adjusting the amount of compressed air provided from the compressor to the cooling ejector Cooling device of the reflow solder machine comprising a.

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