JP2007149784A - Solder feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solder feeder which has the best of both a solder feeder using a solid solder, and a solder feeder using a liquid solder. <P>SOLUTION: The solder feeder has a nozzle 22 in a lower end of a melting pot 21 having the structure of a sealed container and discharges a liquid solder 20 inside the melting pot 21 little by little onto a lead frame 3 through the nozzle 22. The melting pot 21 is equipped with a solder heating means 30 which heats the liquid solder 20 to keep it in a liquid state, a discharge control means 40 which changes over the internal pressure of the melting pot 21 between positive pressure by the supply of a pressurization gas and negative pressure by vacuum suction, a quantity-of-solder detecting means 50 which is a liquid level sensor for detecting the volume of the liquid solder 20, and a solder replenishing means 60 which feeds a solder wire 61 of a solid solder into the melting pot 21 based on the detection signal of the quantity-of-solder detecting means 50 to replenish the liquid solder 20. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a solder supply device used for a die bonder which is a manufacturing facility of a semiconductor device.

  A die bonder of a facility for manufacturing a semiconductor device using a lead frame supplies a certain amount of solder to an island of the lead frame, and a semiconductor chip is mounted on the supplied solder. Solder supply to the lead frame in this die bonder is largely applied to devices that supply solid solder such as solder wires, solder tapes, and solder balls onto the lead frame, and devices that supply liquid solder obtained by melting solid solder onto the lead frame. Separated.

  A solder supply apparatus using a solder wire feeds the solder wire 1a from the tip of the tool 2 as shown in FIG. The tool 2 and the lead frame 3 relatively move toward and away from each other, and when the two approach each other, the tip of the solder wire 1a drawn out from the tool 2 comes into contact with the island of the lead frame 3. The lead frame 3 is preheated to a temperature higher than the solder melting point by a heating rail (not shown), and melts when the tip of the solder wire 1a comes into contact therewith. The solder 1 supplied to the lead frame 3 has a circular shape, and is pushed and shaped into a rectangular shape slightly larger than the semiconductor chip according to the rectangular semiconductor chip as necessary. Such shaping is performed using a soldering tool (soldering tool) (see, for example, Patent Document 1).

  As shown in FIG. 8, the solder supply device using the solder tape cuts the tip of the long solder tape 1 b and supplies the cut rectangular solder 1 b ′ to the island of the lead frame 3. The solder 1b 'supplied to the lead frame 3 is melted in a rectangular shape. In this case, if the solder 1b 'is a rectangle having the same size as that of the semiconductor chip, it is not necessary to shape it in a later process.

  As shown in FIG. 9, the semiconductor device using the solder balls supplies solder balls 1 c one by one from the tip of the tool 4 onto the lead frame 3. The solder ball 1c fed by its own weight into the tool 4 is extruded toward the lead frame 3 by the pressurized gas fed to the tool 4 and melted. The solder 1 supplied on the lead frame 3 is circular, and is shaped by being pushed out into a rectangular shape slightly larger than the semiconductor chip according to the rectangular semiconductor chip as necessary. This shaping is also performed using the soldering tool described above.

  An example of a solder supply device for supplying liquid solder directly onto the lead frame is shown in FIG. The solder supply device shown in FIG. 10 (see, for example, Patent Document 2) heats and melts the solder ingot charged into the solder pot 5 with the heater 6. A small diameter nozzle 7 is formed at the lower end of the solder pot 5, and the upper end opening of the solder pot 5 is closed with a lid 8. A gas pipe 9 is connected to the lid 8. A pressurized gas is supplied from the gas pipe 9 into the solder pot 5 so that the space above the liquid solder 1d in the pot is positive. With this positive pressure, a small amount of liquid solder 1d is discharged from the nozzle 7 onto the lead frame 3. In this way, the solder 1 supplied onto the lead frame 3 is also shaped by being pushed out into a rectangular shape slightly larger than the semiconductor chip in accordance with the rectangular semiconductor chip as necessary.

FIG. 11 shows another example of a solder supply apparatus that melts solid solder and supplies it onto the lead frame. The solder supply device shown in FIG. 11 inserts the solder wire 1e into the tool 10 and supplies it to the lead frame 3 in small amounts while being heated and melted by the heater 11 installed at the tip of the tool 10. The solder wire 1e is fed into the tip portion of the tool 10, and the solder wire 1e is sequentially melted at the timing when the solder wire 1e is slid and fed into the tool hole 10 ′ at the tip portion of the tool 10. The tool hole 10 ′ is filled with the liquid solder 1 e ′, and the liquid solder 1 e ′ is discharged from the tip of the tool 10 by the feeding force and gas pressure of the solder wire 1 e from above and supplied onto the lead frame 3. Also in this case, the solder 1 supplied on the lead frame 3 is pushed and shaped into a rectangle slightly larger than the semiconductor chip in accordance with the rectangular semiconductor chip as necessary.
Japanese Patent Laid-Open No. 04-158536 (FIG. 2) Japanese Patent Laid-Open No. 04-072639 (FIG. 1)

  Each of the solder supply apparatuses shown in FIGS. 7 to 9 can continuously supply the lead frame by continuously supplying solder wires, solder tapes, and solder balls. However, if solid solder is supplied onto the lead frame and melted by the heat of the lead frame, the metallurgical reaction (segregation) proceeds at the joint portion of the solder with the lead frame, and the quality of the joint portion deteriorates. There is. For example, as shown in FIGS. 12A and 12B, when a solder wire or a solder ball is supplied onto the lead frame 3 and melted, segregation progresses to the peripheral portion 1f of the molten circular liquid solder 1. As a result, the wettability with the metal decreases. When this liquid solder 1 is spread out into a substantially rectangular shape as shown in FIG. 12C using a soldering tool (not shown), the periphery 1f of the original circular liquid solder 1 remains with poor wettability. Affects the mountability of a rectangular semiconductor chip.

  Further, although not shown, the liquid solder obtained by cutting the solder tape into a rectangle and melting it on the lead frame also has a metallic reaction at its peripheral edge, resulting in a decrease in wettability. In this case, a rectangular semiconductor chip of approximately the same size is mounted on a substantially rectangular liquid solder, but the bonding property between the semiconductor chip and the peripheral portion of the liquid solder is deteriorated, and the mountability becomes unstable. There is.

  Furthermore, it is difficult for each solder supply device using solid solder to accurately supply a fixed amount of solid solder to a fixed position on the lead frame. For this reason, the shape, amount, and position of the solder supplied onto the lead frame vary, which may make the mountability of the subsequent semiconductor chip unstable.

  The solder supply apparatus shown in FIG. 10 is less affected by the quality deterioration due to the metallurgical reaction because the molten solder is directly supplied onto the lead frame. However, when the liquid solder melted by heating the solder ingot in the solder pot decreases to the lower limit value, the solder supply operation must be temporarily stopped, and a new solder ingot must be added to melt the continuous solder supply. Can not. The introduction of a new solder ingot is performed by opening the lid of the solder pot. At this time, the solder in the pot may be oxidized to deteriorate the quality. In addition, the amount of solder discharged from the nozzle at the lower end of the solder pot fluctuates due to a change in the water head pressure due to a vertical change in the liquid level of the liquid solder in the solder pot and a slight change in the pressurized gas pressure, resulting in accurate solder supply. Is difficult to control.

  In addition, the solder supply device shown in FIG. 11 can be continuously supplied in the same manner as the device in FIG. 7 because the solder wire is used, and the quality deterioration due to metallurgical reaction is caused in the same manner as the device in FIG. Although there is little influence, there are the following problems. As shown in FIG. 11, when the solder wire 1e is inserted into the tool hole 10 'at the tip of the tool 10 and heated and melted, the liquid solder 1e' melted at the tip of the solid solder wire 1e and the tool hole 10 '. The solid-liquid fusion part, which is the boundary part, is unstable in both temperature and shape. Therefore, the solid-liquid fusion portion temporarily solidifies during operation of continuously feeding the solder wire 1e to the tool 10 and clogs at the entrance of the tool hole 10 ', and the amount of solder supplied to the lead frame varies due to this wire clogging. There is a problem that the reliability of continuous solder supply operation is lacking.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a solder supply apparatus that takes advantage of both the solder supply apparatus using solid solder and the solder supply apparatus using liquid solder.

  In order to achieve the above object, the present invention provides a crucible having a hermetically sealed container structure that discharges stored liquid solder from a nozzle portion provided at the lower end, solder heating means that heats and melts the solder in the crucible, and internal pressure of the crucible. Discharge control means for switching control between positive pressure for discharging liquid solder from the nozzle section and negative pressure for stopping discharge of liquid solder from the nozzle section, solder amount detection means for detecting the volume of liquid solder in the crucible, and solder And solder replenishing means for replenishing solid solder in the crucible based on the detection signal of the quantity detecting means.

  Here, as the crucible, a small-volume sealed container formed of a ceramic metal material having poor wettability with liquid solder can be applied. The main difference between this crucible and the solder pot of the above-described conventional apparatus is that the size and volume required by both are markedly different. Since the crucible always contains a certain amount of liquid solder and is supplied to the lead frame or the like and solid solder is replenished in accordance with the reduced amount, the volume can be set to the minimum necessary. On the other hand, the conventional solder pot accommodates and melts a large amount of solder ingots at a time, and therefore requires a volume several times that of the crucible. Further, since the solder heating means attached to the crucible heats and melts a small amount of solder in a small volume crucible, a small heater with a small calorific value can be applied. Solid solder replenished in the crucible by the solder replenishment means can be applied to solder tape, solder balls, solder wires, and is effective for fine adjustment of the replenishment amount.

  In the present invention, the discharge control means for controlling the discharge and stoppage of the liquid solder in the crucible includes a gas supply system for supplying a pressurized gas into the crucible to make a positive pressure, and a pressurization supplied in the crucible. It can be set as the structure provided with the gas suction system which suck | inhales gas and makes a negative pressure. The gas supply system of the discharge control means preferably supplies a mixed gas of an inert gas such as nitrogen gas and a reducing gas such as hydrogen gas into the crucible. When the pressurized gas of such a mixed gas is fed into the crucible, it discharges liquid solder from the nozzle part, prevents oxidation of the liquid solder in the crucible, and reduces it to stabilize the solder quality. Let The gas suction system is a vacuum suction system that is directly connected to the vacuum pump, and by stopping the discharge of the liquid solder from the nozzle portion by setting the inside of the crucible to a negative pressure, the dripping is prevented. The gas supply system and the gas suction system are connected to a common crucible via a switching valve, and the switching valve is appropriately switched in accordance with the solder supply operation.

  In the present invention, the solder amount detection means can be structured to include an energized liquid level sensor that detects the liquid level height of the liquid solder in the crucible. This energizing type liquid level sensor has an electrode installed at a fixed position in the crucible, and when the electrode is immersed in the liquid surface of the liquid solder in the crucible, the liquid solder is energized to detect that the liquid level is at the height of the electrode. When the liquid level is lowered to a height away from the electrode, it is detected that the liquid solder is not energized and the liquid level is lowered below a predetermined height of the electrode. By detecting the change in the liquid level, an increase or decrease in the volume of the liquid solder in the crucible is detected. With this detection, it is possible to accurately control the volume of the liquid solder at a predetermined value. The solder amount detection means is not limited to the energized liquid level sensor, but an optical liquid level sensor that optically detects the vertical movement of the liquid level of the liquid solder, and the gas pressure fluctuation of the pressurized gas supplied into the crucible. It is also possible to apply a gas pressure sensor device that detects the volume of the liquid solder.

  Further, in the present invention, the solder replenishing means includes a solder wire inserted into the crucible from the outside of the crucible toward the liquid solder in the crucible, and a wire feeding mechanism for feeding the solder wire from the outside of the crucible to the inside of the crucible. It can be set as the structure provided. The wire diameter of the solder wire here is arbitrary, and is inserted into the crucible through the lid or side wall of the crucible through a sealing material. Solder is supplied to a lead frame or the like using a crucible, and when the volume of liquid solder in the crucible decreases and the liquid level falls slightly from a specified height, this is detected by the solder amount detecting means. Based on this detection signal, the solder wire is fed into the crucible, the tip of the solder wire is immersed and melted in the liquid solder, and the liquid solder is replenished according to the decrease in the liquid solder. By doing so, the volume of the liquid solder in the crucible can be controlled to a substantially constant value, and the liquid solder can be always supplied with a stable and consistent gas pressure and water head pressure.

  Further, in the present invention, the nozzle portion at the lower end of the crucible is provided with an inverted dish-shaped soldering tool for spreading and shaping the liquid solder discharged from the discharge port for discharging the liquid solder in the crucible radially. Structure. It should be noted that the crucible nozzle portion may be configured with only nozzle holes provided in the bottom of the crucible. Depending on the amount of solder supplied to a solder supply target such as a lead frame and the shape required for the supplied solder, the solder discharged from the nozzle hole is pushed out with a soldering tool and shaped into a predetermined shape. In many cases, the soldering tool itself is formed integrally with the nozzle portion of the crucible. In this way, the soldering operation is performed simultaneously during the operation of discharging the liquid solder from the nozzle portion, and the workability of supplying solder is improved.

  According to the solder supply device of the present invention, when a part of the liquid solder in the crucible is discharged from the nozzle portion and the volume is reduced, this is detected by the solder amount detection means, and the solder replenishment means is an amount corresponding to the decrease. Therefore, the liquid solder can be continuously supplied to the lead frame or the like, and the amount of the liquid solder in the crucible is maintained at a substantially constant value during the continuous supply. Therefore, the total volume of liquid solder in the crucible can be reduced to the minimum necessary amount, and a small and lightweight solder can be applied to the crucible, and the small amount of solder in the crucible can be efficiently heated by a heating means such as a heater. Thus, an excellent effect that the liquid solder can be obtained can be obtained. In addition, since the inside of the crucible with a sealed container structure can always be maintained in an inert gas atmosphere, there is no need to worry about quality deterioration of the liquid solder in the crucible, and high quality solder is always used as a solder supply object such as a lead frame. Can be supplied.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  The solder supply apparatus shown in FIG. 1 includes a crucible 21 having a sealed container structure. The crucible 21 is a small-capacity ceramic metal cylinder having a funnel-shaped nozzle portion 22 at the lower end and a lid 23 integrally at the upper end. The liquid solder 20 is accommodated in the crucible 21 with the volume controlled almost quantitatively. The liquid solder 20 is discharged little by little from the nozzle portion 22 and supplied onto the solder supply object, for example, the lead frame 3. The lead frame 2 is used in a die bonder that is a manufacturing facility of a semiconductor device, and a certain amount of solder is supplied to a plurality of islands of the lead frame 2 and a semiconductor chip is mounted on the supplied solder.

  The crucible 21 for supplying solder to the lead frame 2 has a minimum required volume, for example, (inner diameter) 5 mm × (height) 20 mm. Solder heating means 30 that heats the liquid solder 20 to the crucible 21 and maintains the liquid solder, discharge control means 40 that switches and controls the internal pressure of the crucible 21 between positive pressure and negative pressure, and solder that detects the volume of the liquid solder 20 An amount detecting means 50 and a solder replenishing means 60 for replenishing solid solder in the crucible 21 based on a detection signal from the solder amount detecting means 50 are installed. The nozzle portion 22 provided at the lower end of the crucible 21 includes a nozzle hole 23 that passes through the center of the funnel-shaped bottom surface of the crucible 21 and an inverted dish-shaped soldering tool 24 that extends laterally from the lower end opening of the nozzle hole 23. Is provided.

  The solder heating means 30 includes a cylindrical heater 31 attached to the lower outer periphery of the crucible 21. By energizing the heater 31, the crucible 21 is heated and the internal solder is melted to form the liquid solder 20. The heater 31 has an energization amount controlled so that the liquid solder 20 always maintains an appropriate temperature.

  The discharge control means 40 switches and controls the internal pressure of the crucible 21 between a positive pressure for discharging the liquid solder 20 from the nozzle portion 22 and a negative pressure for stopping the discharge of the liquid solder 20 from the nozzle portion 22. The discharge control means 40 shown in FIG. 1 supplies a pressurized gas from the compressor 42 into the crucible 21 to make it positive pressure, and the inside of the crucible 21 is appropriately vacuumed by a vacuum pump 44. A gas suction system 43 for negative pressure is provided. The gas supply system 41 and the gas suction system 43 are connected to a gas inlet / outlet 25 formed in the lid portion 23 of the crucible 21 via a switching valve 45. The switching valve 45 is appropriately switched in accordance with the solder supply operation. The switching valve 45 shown in FIG. 1 connects the crucible 21 and the gas suction system 43 so that the inside of the crucible 21 is held at a negative pressure, so that the discharge of the liquid solder 20 from the nozzle portion 22 is stopped and dripping is prevented. Is done. The switching valve 45 shown in FIG. 2 connects the crucible 21 and the gas supply system 41 so that the inside of the crucible 21 is held at a positive pressure, and the liquid solder 20 is discharged little by little from the nozzle portion 22 as will be described later. The pressurized gas fed from the gas supply system 41 into the crucible 21 is a mixed gas of an inert gas of nitrogen gas and a reducing gas of hydrogen gas, which prevents oxidation of the liquid solder 20 in the crucible 21 and has a high quality. To maintain. The gas suction system 43 sucks the mixed gas in the crucible 21 and maintains an atmosphere for preventing solder oxidation in the crucible 21.

  The solder amount detection means 50 detects the liquid level height of the liquid solder 20 in the crucible 21 to detect the volume increase / decrease of the liquid solder 20 and controls so that the volume is maintained within a specified range. The solder amount detection means 50 shown in FIG. 1 includes two electrode bars 51 and 52 installed in the crucible 21, a galvanometer 53 that detects the presence / absence of energization between the electrode bars 51 and 52, and a power source 54. In the energization type liquid level sensor provided, the solder amount detection means 50 is hereinafter referred to as a liquid level sensor 50 as necessary. The pair of electrode bars 51, 52 of the liquid level sensor 50 extend downward from the upper end portion in the crucible 21, and the lower ends of each are fixed to the liquid level of the liquid solder 20. As shown in FIG. 4A, when the liquid level of the liquid solder 20 falls below the lower end of at least one of the electrode rods 51 and 52, the energization between the electrode rods 51 and 52 is stopped. 53 detects that the volume of the liquid solder 20 has decreased from the specified value. As shown in FIG. 4B, when the liquid level of the liquid solder 20 rises from the lower ends of both electrode bars 51 and 52 and the lower ends of both electrode bars 51 and 52 are immersed in the liquid solder 20, both electrode bars Energization through the liquid solder 20 occurs between 51 and 52, and this is detected by the galvanometer 53, and it is detected that the volume of the liquid solder 20 has increased to a specified value. A detection signal of the galvanometer 53 is sent to a control circuit (not shown) of the solder replenishing means 60, and the solder replenishing means 60 is operated to control the liquid solder 20 in the crucible 21 to be almost quantitative.

  The solder replenishing means 60 feeds the solder wire 61 of the fixed solder into the crucible 21 according to the reduced amount of the liquid solder 20, and the tip portion of the solder wire 61 is immersed in the liquid solder 20 and melted. The feeding of the solder wire 61 into the crucible 21 is performed by the wire feeding mechanism 63. The wire feed mechanism 63 is arranged between a spool 64 around which a long solder wire 61 is wound, a guide 65 that guides the solder wire 61 fed out of the spool 64 to the crucible 21, and between the guide 65 and the crucible 21. A pair of feed rollers 66 and 67 are provided. The feed rollers 66 and 67 are a pair of a rubber roller and a metal roller, and both of the rollers rotate while sandwiching the solder wire 61 so that the solder wire 61 is fed into the crucible 21. The solder wire 61 passes through the sealing material 62 fixed by penetrating through the lid portion 23 of the crucible 21 and is fed into the crucible 21 so that the inside of the crucible 21 is maintained in an airtight inert / reducing gas atmosphere.

  Next, an example of solder supply operation according to the above-described embodiment will be described.

  In the state of FIG. 1, a certain amount of liquid solder 20 is accommodated in the crucible 21, and the inside of the crucible 21 is controlled to a negative pressure, thereby preventing discharge and dripping of the liquid solder 20. In this state, the crucible 21 descends toward the lead frame 3, and the switching valve 45 is gasified at the timing when the lower surface of the soldering tool 24 contacts the lead frame 3 as shown in FIG. Switch to the supply system 41. Pressurized gas is supplied to the crucible 21, the crucible 21 becomes positive pressure, the liquid solder 20 is pushed out into the nozzle hole 23, and radiates from the discharge port at the lower end of the nozzle hole 23 to the internal space of the soldering tool 24. spread. The internal space of the solder tapping tool 24 is a rectangular space that is substantially the same as the rectangular semiconductor chip, and the switching valve 45 is switched to the gas suction system 43 at the discharge timing so that the liquid solder 20 is filled into the internal space. As shown in FIG. 3A, when the crucible 21 is raised with respect to the lead frame 3, a fixed amount of solder 20 a determined by the soldering tool 24 remains on the lead frame 3. The solder 20a has a substantially rectangular shape as shown in FIG. 3B, and a semiconductor chip 70 indicated by a chain line in FIG. 3B is mounted on the solder 20a in a later process. Since the solder 20a discharges the liquid solder 20 directly onto the lead frame 3, and is shaped by the soldering tool 24 simultaneously with the discharge, the metal reaction with the lead frame 3 hardly progresses, and the semiconductor chip 70 is always Bonded with good mountability. Further, since the soldering tool 24 is formed integrally with the crucible 21 and shaped simultaneously with the solder discharge, a special soldering process can be omitted and chip mounting can be performed.

  In the above-described solder supply operation, the solder amount detection means 50 monitors the solder amount from the liquid level of the liquid solder 20 in the crucible 21, and the amount of solder is reduced to a predetermined value or less to stop energization from the galvanometer 53. When the signal is output to the control circuit of the solder replenishing means 60, the wire feeding mechanism 63 is activated to feed the solder wire 61 into the crucible 21. As shown in FIG. 4B, when the solder wire 61 is fed by the rotation of the feed rollers 66 and 67, the tip of the solder wire 61 is inserted into the liquid solder 20 and melted simultaneously with the insertion. By controlling the feed amount of the solder wire 61 according to the decrease in the liquid solder 20, the volume of the liquid solder 20 in the crucible 21 is kept substantially constant, and the liquid level height of the liquid solder 20 in the crucible 21 is maintained. It is maintained almost constant. Accordingly, it is possible to easily control the gas pressure and the water head pressure when discharging the liquid solder 20 from the nozzle portion 22, and it is possible to always control the discharge amount to be constant, so that the solder on the lead frame 3 can be controlled. Accurate control of the supply amount is facilitated. In addition, since the liquid solder 20 in the crucible 21 is controlled in a fixed amount, the solder supply operation to a plurality of locations of the lead frame 3 and to the plurality of lead frames 3 can be performed continuously without stopping.

  In addition, the solder supply apparatus of this invention is not limited to above-described embodiment, Of course, various changes can be added within the range which does not deviate from the summary of this invention.

  For example, as shown in FIG. 5, a soldering tool 24 ′ may be detachably attached to the lower end portion of the crucible 21. The nozzle portion 22 at the lower end of the crucible 21 is formed in a funnel shape, and a separate soldering tool 24 ′ is attached to the nozzle portion 22 in a detachable manner by screwing or pinning. Replace the soldering tool 24 'of the type corresponding to the amount of solder supplied on the lead frame 3 with a single operation of the crucible 21 and the shape to be shaped by replacement with another type of soldering tool. Install as possible.

  Further, the soldering tool 24 'is removed from the crucible 21 of FIG. 5, and the liquid solder 20 is directly discharged to the lead frame 3 by the nozzle portion 22 without the soldering tool as shown in FIG. It is also possible to do. In this case, the liquid solder 20 is supplied on the lead frame 3 in a circular dot shape, and shaping is performed later by soldering as necessary.

It is sectional drawing of the principal part which shows embodiment of the solder supply apparatus which concerns on this invention. It is sectional drawing at the time of the solder supply operation | movement of the apparatus of FIG. (A) is sectional drawing after solder supply, (B) is a top view of the supplied solder. (A), (B) is the partial front view at the time of each operation | movement for demonstrating the solder amount detection means in the FIG. 1 apparatus. It is a fragmentary sectional view of a crucible which shows other embodiments. It is a fragmentary sectional view of a crucible which shows other embodiments. It is sectional drawing of the principal part of the conventional solder supply apparatus. It is sectional drawing of the principal part of another conventional solder supply apparatus. It is sectional drawing of the principal part of another conventional solder supply apparatus. It is sectional drawing of the principal part of another conventional solder supply apparatus. It is sectional drawing of the principal part of another conventional solder supply apparatus. (A) is a plan view in which solid solder is supplied onto a lead frame, (B) is a side view of (A), and (C) is a plan view when the solder of (A) is shaped into a rectangle.

Explanation of symbols

3 Lead frame 20 Liquid solder 21 Crucible 22 Nozzle part 23 Nozzle hole 23 Lid part 24 Soldering tool 30 Solder heating means 31 Heater 40 Discharge control means 41 Gas supply system 43 Gas suction system 44 Vacuum pump 45 Switching valve 50 Solder amount detection means 50 Liquid level sensors 51, 52 Electrode bar 53 Galvanometer 54 Power supply 60 Solder replenishing means 61 Solid solder, solder wire 62 Sealing material 63 Wire feed mechanism

Claims (5)

A crucible having a sealed container structure for discharging the contained liquid solder from a nozzle portion provided at a lower end portion;
Solder heating means for heating and melting the solder in the crucible;
A discharge control means for switching and controlling the internal pressure of the crucible between a positive pressure for discharging liquid solder from the nozzle portion and a negative pressure for stopping discharge of liquid solder from the nozzle portion;
Solder amount detection means for detecting the volume of liquid solder in the crucible;
Solder replenishing means for replenishing solid solder in the crucible based on the detection signal of the solder amount detecting means;
A solder supply device comprising:   The discharge control means includes a gas supply system for supplying a pressurized gas into the crucible to make a positive pressure, and a gas suction system for sucking the pressurized gas supplied into the crucible to make a negative pressure. The solder supply device according to claim 1, wherein the solder supply device is provided.   3. The solder supply device according to claim 1, wherein the solder amount detection unit includes an energization type liquid level sensor that detects a liquid level of the liquid solder in the crucible.   The solder replenishing means comprises a solder wire inserted into the crucible from the outside of the crucible toward the liquid solder in the crucible, and a wire feeding mechanism for feeding the solder wire from the outside of the crucible to the inside of the crucible. The solder supply device according to any one of claims 1 to 3, wherein   The nozzle unit includes an inverted dish-shaped soldering tool that radially expands and shapes the liquid solder discharged from a discharge port for discharging the liquid solder in the crucible to the side. 4. The solder supply device according to claim 4.

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