JP7761464B2 - soldering equipment - Google Patents

Description

This disclosure relates to a soldering apparatus, and in particular to the structure of a jet nozzle provided in a soldering apparatus.

In partial soldering, which solders electronic components to a circuit board, for example, as disclosed in Figure 1 of Patent Document 1, a jet nozzle is positioned higher than the liquid surface of the solder bath, and molten solder is ejected from the opening at the tip of the jet nozzle, soldering the circuit board and the lead terminals of the electronic components with the ejected molten solder.

JP 2010-120031 A

The jet nozzle disclosed in Patent Document 1 has a large opening area, making it impossible to control the solder flow rate for each lead terminal, resulting in temperature variations and unstable soldering for each lead terminal. Furthermore, because the jet nozzle has openings across the entire longitudinal length and a large opening area, the insufficient solder flow rate can cause debris (solder residue) on the surface of the molten solder to stagnate.

This disclosure has been made to solve the problems described above, and aims to provide a jet nozzle for partial soldering that efficiently discharges debris and shortens soldering time.

A soldering apparatus according to the present disclosure is a soldering apparatus for soldering a plurality of lead terminals of an electronic component to a circuit board, the soldering apparatus comprising: a solder bath for storing molten solder; a circulation mechanism for circulating the molten solder; and a jet nozzle that receives the molten solder from the circulation mechanism and jets the molten solder into a jet, the jet nozzle having a plurality of side walls that define an opening from which the molten solder is jetted, the jet nozzle having the circuit board, to which the electronic component is attached, positioned above the opening on at least one of the side walls so that the plurality of lead terminals pass through, the jet nozzle having at least one notch at a position where the plurality of lead terminals face the at least one side wall when the plurality of lead terminals are inserted into the opening, the notch width and notch length being greater than the lead terminal width and length , the opening has a rectangular shape in a plan view, and the plurality of side walls are arranged such that a first side wall and a second side wall are arranged in a longitudinal direction of the opening. and a second side wall, and a third side wall and a fourth side wall in a lateral direction of the opening, wherein the jet nozzle has a first side wall among the plurality of side walls, a first notch provided along the longitudinal direction, a third notch and a fourth notch provided along the lateral direction in the third side wall and the fourth side wall, respectively, and a second side wall, a second notch provided along the longitudinal direction, and The plurality of first notches include a central notch and two small notches provided on both sides of the central notch, each of the plurality of second notches has the same opening area as each of the two small notches, and the central notch has a larger notch width and a smaller notch length than each of the two small notches and each of the plurality of second notches, and its opening area is the same as the opening area of the plurality of second notches at a position facing the central notch .

The soldering device according to the present disclosure provides at least one notch at a position where multiple lead terminals face at least one side wall, allowing the solder flow to directly contact the lead terminals. Furthermore, by locally increasing the solder flow speed, the temperature of the lead terminals can be more easily increased. Furthermore, by locally increasing the solder flow speed, debris stagnating on the surface of the jet nozzle can be moved, allowing the debris to be efficiently expelled outside the jet nozzle.

1 is a cross-sectional view showing the configuration of a soldering apparatus according to the present disclosure. 1 is a perspective view showing the positional relationship between a circuit board and a jet nozzle of embodiment 1 during partial soldering. FIG. 10 is a diagram showing the positional relationship between a circuit board and the jet nozzle of the first embodiment during partial soldering. FIG. 1 is a perspective view showing a configuration of a jet nozzle according to a first embodiment. FIG. FIG. 10 is a perspective view showing the configuration of a jet nozzle according to a second embodiment. FIG. 10 is a perspective view showing the configuration of a jet nozzle according to a third embodiment. FIG. 11 is a plan view showing the positional relationship between the jet nozzle and the lead terminal according to the third embodiment. FIG. 10 is a perspective view showing the configuration of a jet nozzle according to a fourth embodiment. FIG. 10 is a plan view showing the positional relationship between the jet nozzle and the lead terminal according to the fourth embodiment. 13A and 13B are diagrams illustrating the configuration of a jet nozzle according to a fifth embodiment and the positional relationship with a circuit board. FIG. 13 is a plan view showing the positional relationship between the jet nozzle and the lead terminal according to the fifth embodiment. FIG. 13 is a plan view showing the positional relationship between the jet nozzle and the lead terminal according to the sixth embodiment. 13 is a diagram showing the configuration of a jet nozzle according to a seventh embodiment and the positional relationship with a circuit board. FIG. 13 is a diagram showing the configuration of a jet nozzle according to an eighth embodiment and the positional relationship with a circuit board. FIG. FIG. 13 is a side view of the soldering apparatus of the ninth embodiment during partial soldering.

First Embodiment
Fig. 1 is a cross-sectional view showing the configuration of a soldering apparatus 100 according to the present disclosure. As shown in Fig. 1, the soldering apparatus 100 includes a solder bath 200 that contains molten solder 7, a heater 201 that houses the solder bath 200 and heats the molten solder 7 in the solder bath 200, a pump 203 that is disposed in the molten solder 7 in the solder bath 200 and sends the molten solder 7 into a duct 204, a motor 205 that is disposed above the liquid surface of the molten solder 7 and provides a rotational force to the pump 203, and a transmission mechanism 206 that transmits the rotation of the motor 205 to the pump 203.

A shield plate 2041 that blocks the molten solder 7 is provided at the tip opening of the duct 204, which is located above the liquid surface of the molten solder 7, and a jet nozzle 6 is provided on the shield plate 2041. The jet nozzle 6 is attached to an opening that penetrates the shield plate 2041, and the molten solder 7 stored in the solder tank 200 is sprayed from the jet nozzle 6 to form a solder jet.

The temperature of the solder bath 200 is maintained above the melting point of the solder by a heater 201. Molten solder 7 stored in the solder bath 200 is ejected from the jet nozzle 6 and supplied to electronic components on a circuit board (not shown) placed above the opening of the jet nozzle 6.

Pump 203 is connected to motor 205, and begins operation as motor 205 rotates. Pump 203 and motor 205 form a circulation mechanism for molten solder 7. When pump 203 operates while solder bath 200 is filled with molten solder 7, circulation of molten solder 7 begins inside solder bath 200, and molten solder 7 is ejected from jet nozzle 6 through duct 204. Molten solder 7 not used in soldering flows along the wall of jet nozzle 6 and the surface of shield plate 2041 and returns to solder bath 200. When motor 205 stops rotating, the jet of molten solder 7 from jet nozzle 6 stops.

Next, partial soldering using the jet nozzle according to embodiment 1 will be described using Figures 2, 3, and 4. Figure 2 is a perspective view showing the positional relationship between the circuit board 3 and the jet nozzle 6 during partial soldering, Figure 3 is a diagram showing the positional relationship between the circuit board 3 and the jet nozzle 6 during partial soldering, and Figure 4 is a perspective view of the jet nozzle 6.

As shown in Figure 2, the jet nozzle 6 solders multiple lead terminals 2 and the circuit board 3 all at once. The jet nozzle 6 has a longitudinal direction parallel to the arrangement direction of the multiple lead terminals 2 and a lateral direction perpendicular to the longitudinal direction, and has a rectangular shape in plan view when viewed from the circuit board 3 side.

As shown in Figure 2, in partial soldering, lead terminals 2 protruding from the side of a modularized electronic component (hereinafter referred to as module 1) and bent toward a circuit board 3 are inserted into through holes 8 in the circuit board 3, and the circuit board 3 is then placed over the opening of a jet nozzle 6. For simplicity's sake, the mechanism for placing the circuit board 3 over the opening of the jet nozzle 6 is not shown.

The circuit board 3 is placed above the jet nozzle 6 so as not to come into contact with the opening of the jet nozzle 6, and the tips of the lead terminals 2 inserted into the through holes 8 protrude from the back surface of the circuit board 3. Copper patterns 9 are formed around the through holes 8 and on the inner walls of the through holes 8 on both the front and back surfaces of the circuit board 3.

When molten solder 7 is ejected from the jet nozzle 6, the solder flows into the through-holes 8, forming solder fillets between the lead terminals 2 and the copper patterns 9 on the front and back surfaces of the circuit board 3, thereby soldering the lead terminals 2 to the circuit board 3.

As shown in Figure 4, one side wall (first side wall) along the longitudinal direction of the jet nozzle 6 has multiple notches 4 (first notches) along the longitudinal direction, but the other side wall (second side wall) along the longitudinal direction does not have any notches 4. Furthermore, one side wall (third side wall) along the lateral direction and the other side wall (fourth side wall) along the lateral direction do not have any notches.

Also, as shown in Figure 3, the longitudinal notches 4 are provided at positions corresponding to the lead terminals 2, and by having one notch 4 face one lead terminal 2, the surface of the lead terminal 2 comes into direct contact with the solder flow. As shown in Figure 3, the notch width A11 and notch length A12 of the notch 4 are formed slightly larger than the width and length of the lead terminal 2 protruding from the circuit board 3.

In this way, by providing a notch 4 with a small opening area similar to the shape of the lead terminal 2, the solder flow rate increases locally, the temperature of the lead terminal 2 and circuit board 3 rises more quickly, and the soldering time can be adjusted.

Furthermore, in typical partial soldering, debris circulating in the solder bath floats out of the jet nozzle and accumulates on the solder surface. Alternatively, if the soldering equipment is used for an extended period of time, an oxide film may form on the solder surface over time. While this oxide film has a smaller oxidation rate than the debris, if soldering is performed in this state, the debris contained in the jet solder will adhere to the lead terminals. Furthermore, the presence of an oxide film can act as an inclusion between the lead terminals and the solder, preventing direct contact between the lead terminals and the solder, reducing the solder's ability to spread and resulting in poor soldering. However, by providing notches 4 with small opening areas along the longitudinal direction of the jet nozzle 6, the solder flow rate can be increased locally, moving debris and other debris that has accumulated on the surface of the jet nozzle 6 and efficiently removing it.

Here, the notch width A11 of the notch 4 in the jet nozzle 6 is formed larger than the width of the lead terminal 2. For example, for a lead terminal width of 0.3 mm to 5.0 mm, a clearance of 1 mm to 3 mm can be provided on one side. If the notch width A11 is smaller than the width of the lead terminal 2, the solder flow will not hit the entire surface of the lead terminal 2, making it difficult for the temperature of the lead terminal 2 to rise. On the other hand, if the notch width A11 is too large, the solder flow rate will be slower, making it difficult for debris to move, and the debris will not be able to be discharged outside the jet nozzle 6.

The notch length A12 of the notch 4 in the jet nozzle 6 is formed so that the bottom of the notch is deeper than the bottom of the lead terminal 2 protruding from the circuit board 3. For example, if the length of the lead terminal 2 is 1.0 mm to 3.0 mm, a clearance of 1.0 mm to 6.0 mm can be provided from the bottom of the lead terminal 2. If the notch length A12 is shorter than the length of the lead terminal 2, the solder flow will not hit the entire surface of the lead terminal 2, making it difficult for the temperature of the lead terminal 2 to rise. On the other hand, if the notch length A12 is too large, the solder flow rate will increase, causing molten solder 7 to splash from the periphery of the jet nozzle 6 and potentially adhering to components near the jet nozzle 6 on the back surface of the circuit board 3.

Also, as shown in Figure 4, the jet nozzle width A13, defined by the short-side length of the opening OP of the jet nozzle 6, can be set to 5.0 mm to 10.0 mm. The closer the width is to the notch 4, the faster the solder flow rate. That is, if the jet nozzle width A13 is greater than 10 mm, the solder flow rate decreases, making it difficult to eject debris from the vicinity of the lead terminal 2 located near the center of the jet nozzle 6, and the temperature of the lead terminal 2 is less likely to rise due to debris adhesion. On the other hand, if the jet nozzle width A13 is less than 5 mm, pressure loss is large, making it difficult for the molten solder 7 to be ejected from the jet nozzle 6, and the molten solder 7 may harden within the jet nozzle 6.

Furthermore, because the molten solder 7 has a high surface tension, it tends to bulge from the inner wall of the jet nozzle 6 toward the center. Therefore, the solder height is large at the center of the jet nozzle 6 and small at the ends of the jet nozzle 6. As a result, if the distance A10 between the circuit board 3 and the jet nozzle 6 is large, the molten solder 7 will come into contact with the circuit board 3 at the center of the jet nozzle 6, but the contact between the molten solder 7 and the circuit board 3 will be small at the longitudinal ends of the jet nozzle 6, potentially resulting in poor soldering. On the other hand, if the distance A10 between the circuit board 3 and the jet nozzle 6 is small, the gap for debris will be small, making it difficult to remove the debris and allowing it to stagnate. Therefore, the distance A10 between the circuit board 3 and the jet nozzle 6 was experimentally set to 2 mm to 6 mm. Furthermore, by providing notches 4 corresponding to each lead terminal 2, it is possible to control the solder flow rate for each and adjust the temperature rise, reducing variations in the temperature of the lead terminals 2 and reducing soldering defects when soldering multiple terminals at once.

The jet nozzle 6 is made of stainless steel (SUS), which solder does not easily adhere to, and the solder is made of a material such as Sn3Ag0.5Cu, which contains tin (Sn), 3% silver (Ag), and 0.5% copper (Cu). Phosphorus (P) may also be added to make the molten solder 7 less susceptible to oxidation.

As explained above, the configuration of the jet nozzle 6 of embodiment 1 provides multiple notches 4 along the longitudinal direction of the jet nozzle 6 at positions on the jet nozzle 6 corresponding to the lead terminals 2, allowing the solder flow to come into direct contact with the lead terminals 2, making it easier to raise the temperature of the lead terminals 2. Furthermore, by reducing the opening area of the notches 4, the solder flow rate can be increased locally, moving debris and other debris that has accumulated on the surface of the jet nozzle 6 and efficiently removing it.

Furthermore, by providing a notch 4 for each lead terminal 2, the solder flow rate can be controlled for each lead terminal 2, and the temperature rise can be adjusted individually, reducing temperature variations between lead terminals 2 and reducing soldering defects when soldering multiple lead terminals at once.

Furthermore, while the above explanation gives an example of soldering the lead terminals 2 of the module 1, the same effect can be obtained when soldering components with lead terminals of different widths and lengths, such as capacitors and connector components.

As explained using Figure 4, the jet nozzle 6 has a rectangular shape in plan view, but this is not limited to this and other shapes in plan view, such as a circular, U-shaped, or L-shaped, are also possible. A circular shape, like a rectangular shape, allows for simultaneous soldering of the lead terminals on each side of the module; a U-shaped shape allows for simultaneous soldering of the lead terminals on both mating sides of the module; and an L-shape allows for simultaneous soldering of the lead terminals on each of the two orthogonal sides of the module.

<Second Embodiment>
FIG. 5 is a perspective view showing the configuration of a jet nozzle 6A according to a second embodiment. The difference from the jet nozzle 6 of the first embodiment shown in FIG. 4 is that notches 5 are provided in two side walls parallel to the short side, i.e., the third and fourth side walls. At the center of the jet nozzle 6, the molten solder 7 is ejected from the entire nozzle, resulting in a large contact area between the molten solder 7 and the circuit board 3, making it easy for the temperature to rise. At the nozzle ends, however, the contact area between the molten solder 7 ejected from the jet nozzle 6 and the circuit board 3 is small, making it difficult for the temperature to rise. Furthermore, at the nozzle ends, the molten solder 7 stagnates due to the lack of a flow path. Therefore, the temperatures of the circuit board 3 and lead terminals 2 tend to be lower at the nozzle ends than at the center.

In contrast, the jet nozzle 6A has longitudinal notches 4 and lateral notches 5, which allow the solder to flow in two directions. The notches with smaller opening areas increase the solder flow rate, making it easier for the temperatures of the circuit board 3 and lead terminals 2 to rise, and shortening the soldering time. Furthermore, the lateral notches 5 allow debris that has accumulated at the end of the jet nozzle 6A to be expelled to the outside of the jet nozzle 6A.

The width of notch 5 in jet nozzle 6A is similar to the width of notch 4 in jet nozzle 6, and for example, for a lead terminal width of 0.3 mm to 5.0 mm, a clearance of 1 mm to 3 mm can be provided on one side. Furthermore, the length of notch 5 is similar to the length of notch 4 in jet nozzle 6, and for example, for a lead terminal 2 length of 1.0 mm to 3.0 mm, a clearance of 1.0 mm to 6.0 mm can be provided from the bottom surface of lead terminal 2.

In this way, by providing a notch 5 at the nozzle end of the jet nozzle 6A of embodiment 2, the temperature of the circuit board 3 and lead terminals 2 increases more easily, shortening the soldering time and making it easier to remove debris.

<Third Embodiment>
FIG. 6 is a perspective view showing the configuration of a jet nozzle 6B according to the third embodiment, and FIG. 7 is a plan view showing the positional relationship between the jet nozzle 6B and the lead terminal 2. As shown in FIG.

The difference from the jet nozzle 6 of embodiment 1 shown in Figure 4 is that one side wall along the longitudinal direction of the jet nozzle 6B has multiple notches 41 (first notches) along the longitudinal direction, and the other side wall has notches 42 (second notches), and one side wall along the lateral direction has notches 5 (third notches), and the other side wall along the lateral direction has notches 5 (fourth notches).

As shown in FIG. 7, the lead terminal 2 is positioned at the widthwise center of the jet nozzle 6B, and is also positioned at the widthwise center of the opposing notches 41 and 42 on one side. The notch width and length of notches 41 and 42 are the same as those of notch 4 of the jet nozzle 6 of embodiment 1 shown in FIG. 4, and the notch width and length of notch 5 are the same as those of notch 5 of the jet nozzle 6A of embodiment 2 shown in FIG. 5.

By providing notches 41 and 42, as in the jet nozzle 6B, molten solder can be ejected from both side walls of the jet nozzle. This allows solder flows in two directions from the notches 41 and 42 on both side walls of the jet nozzle 6B to come into contact with the surface of the lead terminal 2. The small opening area of the notches allows localized solder flow speeds to be created in two directions, further shortening the soldering time between the lead terminal 2 and the circuit board 3. Furthermore, creating localized solder flow speeds in two directions makes it easier to move debris that has accumulated on the surface of the molten solder 7, making it easier to expel it outside the jet nozzle 6B.

In addition, the notch 5 provided in the short direction allows debris stagnating at the end of the jet nozzle 6B to be discharged outside the jet nozzle 6A.

In this way, the jet nozzle 6B of embodiment 3 has multiple notches 41 and 42 on one side wall and the other side wall along the longitudinal direction of the jet nozzle 6B, respectively, which allows the solder flow to come into contact with the surface of the lead terminal 2 in two directions, making it easier to raise the temperature of the lead terminal 2 and the circuit board 3 and further shortening the soldering time between the lead terminal 2 and the circuit board 3. Furthermore, the notches with small opening areas allow localized solder flow speeds to be created in two directions, moving debris stagnating on the surface of the molten solder 7 and more efficiently expelling it outside the jet nozzle 6B. Furthermore, the notches 5 allow debris stagnating at the end of the jet nozzle 6B to be expelled outside the jet nozzle 6A.

<Fourth Embodiment>
FIG. 8 is a perspective view showing the configuration of a jet nozzle 6C according to the fourth embodiment, and FIG. 9 is a plan view showing the positional relationship between the jet nozzle 6C and the lead terminal 2. As shown in FIG.

The difference from the jet nozzle 6 of embodiment 1 shown in Figure 4 is that one side wall along the longitudinal direction of the jet nozzle 6C has multiple notches along the longitudinal direction, including a central notch 43 in the center in the longitudinal direction and notches 41 on both sides of it, while the other side wall has multiple notches 42, and notches 5 are also provided on the two side walls parallel to the lateral direction.

The central notch 43 on one side wall of the jet nozzle 6C is wider and shorter than the notches 41 on either side of it and the notch 42 on the other side wall. For this reason, notches 41 and 42 are sometimes referred to as small notches.

As shown in Figure 9, the lead terminal 2 is positioned so that it is centered in the width direction of the notch 42 provided on the other side wall of the jet nozzle 6C. The central notch 43 and notch 41 provided on one side wall of the jet nozzle 6C are provided so as to roughly correspond to the area between adjacent lead terminals 2 and cover the space between the notches 42 provided on the other side wall of the jet nozzle 6C. As a result, the notch 42 provided on the other side wall of the jet nozzle 6C is used for soldering the lead terminal 2 to the circuit board 3, and the central notch 43 provided on one side wall of the jet nozzle 6C is used for ejecting debris.

Debris is particularly abundant near the center where solder is ejected from the jet nozzle 6C, and large debris can form. For this reason, by increasing the width of the central notch 43 in the longitudinal center of the jet nozzle 6C, it is possible to eject large debris.

Here, the width of the central notch 43 is increased and its length is decreased, giving it the same opening area as two of the notches 42 on the other side wall of the jet nozzle 6C. This makes the solder flow rate from the central notch 43 the same as the solder flow rate from the two notches 42, achieving a balance in flow rates on both side walls of the jet nozzle 6C and enabling both soldering and debris removal. Note that the opening area of the central notch 43 is not limited to two notches 42, and the same effect can be achieved by making the opening area of the central notch 43 the same for multiple notches 42.

In this way, the jet nozzle 6C of embodiment 4 has a central notch 43 with a large opening area on one side wall and multiple notches 42 with small opening areas on the other side wall. The central notch 43 has the same opening area as the multiple small notches 42, making the solder flow rate from the central notch 43 the same as the solder flow rate from the multiple notches 42. This balances the flow rates on both side walls of the jet nozzle 6C, enabling both soldering and debris evacuation. Larger debris can also be expelled from the jet nozzle through the central notch 43 to the outside.

<Fifth Embodiment>
FIG. 10 is a diagram showing the configuration of a jet nozzle 6D according to the fifth embodiment and its positional relationship with the circuit board 3, and FIG. 11 is a plan view showing the positional relationship between the jet nozzle 6D and the lead terminals 2.

The difference from the jet nozzle 6 of embodiment 1 shown in Figure 4 is that, as shown in Figure 11, one side wall along the longitudinal direction of the jet nozzle 6D has multiple notches 45 along the longitudinal direction, and the other side wall has multiple notches 46, and notches 5 are also provided on the two side walls parallel to the lateral direction. Also, the lead terminals 2 are not arranged in a single row at the center of the width of the jet nozzle 6D, but are arranged in a staggered pattern with the terminals positioned off-center.

As shown in Figure 11, the multiple notches 45 and the multiple notches 46 are located at different positions and are formed in a staggered arrangement when viewed from the circuit board 3 side.

The lead terminals 2 of the module 1 may be arranged in a staggered pattern to ensure an insulating distance between the terminals. Because lead terminals 2 arranged in this manner are offset from the center of the jet nozzle 6D in the width direction, they are closer to the side wall of the jet nozzle 6D. By providing a notch 45 or 46 in the side wall of the jet nozzle 6D closest to the lead terminals 2, the solder flow from the notch 45 or 46 can come into contact with the surface of the lead terminals 2.

In addition, because the lead terminal 2 is close to the notch 45 or notch 46, the solder comes into contact with the lead terminal at a high flow rate, shortening the soldering time. Furthermore, by providing the notches 45 and 46 in a staggered arrangement, it is possible to generate a solder flow oblique to the side wall of the jet nozzle 6D, eliminating stagnation in the flow and facilitating the movement of debris.

In this way, in the jet nozzle 6D of embodiment 5, by forming the notches 45 and 46 in a staggered arrangement to match the staggered arrangement of the lead terminals 2, the solder can contact the lead terminals 2 at a high flow rate, shortening the soldering time. Furthermore, by arranging the notches 45 and 46 in a staggered arrangement, the solder also flows diagonally against the sidewall of the jet nozzle 6D, making it easier for debris to move.

Sixth Embodiment
FIG. 12 is a plan view showing the positional relationship between a jet nozzle 6E and a lead terminal 2 according to the sixth embodiment.

As shown in FIG. 12, the jet nozzle 6E has a side wall (first side wall) along the longitudinal direction of the jet nozzle 6E that has a different shape from the other side wall (second side wall). One side wall has multiple depressions 14 recessed in the lateral direction. The portion of the jet nozzle sandwiched between the depressions 14 is convex in plan view, and the side wall of the convex portion has notches 51 extending in the lateral direction. Note that the portion of one side wall along the longitudinal direction, i.e., the portion not forming the depressions 14, has multiple notches 44 extending in the longitudinal direction. In other words, one side wall along the longitudinal direction of the jet nozzle 6E has multiple notches 44 and multiple notches 51 extending along the contour of the side wall. The other side wall has multiple notches 44 extending in the longitudinal direction. In addition, notches 5 are provided in two side walls (the third side wall and the fourth side wall) parallel to the short side direction of the jet nozzle 6D.

In addition, lead terminals 21 and 22 are arranged in a row at the center of the jet nozzle 6E in the width direction, with lead terminal 21 being arranged on the convex portion and lead terminal 22 being arranged in an area where the jet nozzle recess 14 is not provided and at the nozzle end separated by the jet nozzle recess 14.

Generally, a conductor pattern is formed inside module 1, with lead terminals connected to the conductor pattern protruding to the outside of the module. Heat-generating components such as chip components are mounted on this conductor pattern, and the heat generated by the components is transferred and cooled by the conductor pattern. Therefore, even within the same module, the width of the conductor pattern may vary depending on the amount of heat generated. Therefore, even if the width of the lead terminal is the same, if the width of the connected conductor pattern is large, the heat capacity is large and the temperature of the lead terminal is less likely to rise during soldering. On the other hand, if the width of the conductor pattern is small, the heat capacity is small and the temperature of the lead terminal is more likely to rise during soldering.

Here, lead terminal 21 shown in Figure 12 is a terminal to which a conductor pattern to be connected has a large width, while lead terminal 22 is a terminal to which a conductor pattern to be connected has a small width. Therefore, if lead terminal 21 and lead terminal 22 are soldered using a soldering time that is tailored to lead terminal 21, which is less likely to heat up, lead terminal 22 will be exposed to a higher temperature than necessary, causing the copper pattern on circuit board 3 to melt and resulting in poor soldering. On the other hand, if the soldering time is the same as that for lead terminal 22, which is more likely to heat up, lead terminal 21, which is less likely to heat up, will not heat up enough, resulting in poor soldering.

On the other hand, in the jet nozzle 6E of embodiment 6, the lead terminal 21 connected to the conductor pattern with a large heat capacity is positioned on the convex portion defined by the jet nozzle recess 14, so that in the convex portion, the lead terminal 21 faces not only the two-way notch 44 but also the two-way notch 51.

This allows the solder to flow from four directions and come into contact with the surface of the lead terminal 21. Furthermore, the local solder flow rate from all four directions can be increased, which increases the temperature of the lead terminal 21 and the circuit board 3, shortening the soldering time.

As a result, the temperature rise of lead terminals 21 connected to conductor patterns with large heat capacities and the temperature rise of lead terminals 22 connected to conductor patterns with small heat capacities can be adjusted to the same level, making it possible to achieve good soldering all at once, even for lead terminals connected to patterns with different heat capacities.

In addition, in this embodiment, a configuration in which notches are provided in four directions around the lead terminal 21 is shown, but in the case of a lead terminal connected to a conductor pattern whose thermal capacity is smaller than that of the conductor pattern connected to the lead terminal 21 and larger than that of the conductor pattern connected to the lead terminal 21, the same effect can be achieved by arranging the lead terminal in a section with notches in three directions, as in the nozzle end of the jet nozzle 6E shown in Figure 12.

In addition, the lead terminal can be positioned at the center of the width of the jet nozzle 6E, which ensures uniform solder flow.

Seventh Embodiment
FIG. 13 is a diagram showing the configuration of a jet nozzle 6F according to the seventh embodiment and the positional relationship with the circuit board 3. In FIG.

As shown in Figure 13, the jet nozzle 6F has notches 47 and 48 on one side wall along the longitudinal direction of the jet nozzle 6F, with notch widths corresponding to the terminal width of the lead terminals protruding from the module 1.

Generally, the width of the lead terminals in a module is determined by the current that flows through them. In the example of Figure 13, module 1 has lead terminal 2A, which flows a small current, lead terminal 2B, which flows a large current, and lead terminal 2C, which flows a current intermediate between lead terminals 2A and 2C. Lead terminal 2A has the smallest width, lead terminal 2B has the largest width, and lead terminal 2C has a width approximately intermediate between lead terminals 2A and 2B.

Lead terminal 2A, which has the smallest terminal width, has a small heat capacity, so no notch is provided in the corresponding position on the jet nozzle 6F. On the other hand, lead terminal 2B, which has the largest terminal width, has a large heat capacity, so a notch 47 with the largest notch width is provided in the corresponding position on the jet nozzle 6F. Furthermore, because the terminal width of lead terminal 2C is smaller than that of lead terminal 2B, a notch 48 smaller than the terminal width of lead terminal 2B is provided in the corresponding position on the jet nozzle 6F. This allows the temperature rise of lead terminals with different heat capacities to be adjusted to the same level, ensuring good soldering all at once.

Similar notches 47 and 48 can be provided on the other side wall along the longitudinal direction of the jet nozzle 6E.

In this way, the jet nozzle 6F of embodiment 7 has notches with widths that correspond to the terminal widths of multiple types of lead terminals. This makes it possible to adjust the temperature rise of the lead terminals to the same level even if the heat capacity of the lead terminals differs due to differences in the terminal widths of the lead terminals of the module 1, thereby enabling good batch soldering of lead terminals with different heat capacities.

<Eighth Embodiment>
FIG. 14 is a diagram showing the configuration of a jet nozzle 6G according to the seventh embodiment and the positional relationship with the circuit board 3. In FIG.

As shown in Figure 14, the jet nozzle 6G has multiple notches 49 that are inverted trapezoidal in plan view, with the notch width larger on the upper side facing the circuit board 3 and smaller on the lower side, on one side wall along the longitudinal direction of the jet nozzle 6G.

The notch length, upper notch width, and lower notch width of the notch 49 are set so that it has the same opening area as the rectangular notch 4 in plan view shown in Figure 4, for example. Because the notch 49 has the same opening area as the rectangular notch in plan view, the solder flow rate is the same, and the upper opening can be made larger, allowing large debris to be discharged outside the jet nozzle 6G.

The planar shape of the notch 49 can also be semicircular or elliptical. If the planar shape is an inverted trapezoid, the notch 49 is formed by cutting using a laser or other method, but if the shape is semicircular or elliptical, punching can also be used, simplifying production.

The same effect can also be achieved by making the notch provided in the shorter direction of the jet nozzle 6G have an inverted trapezoidal, semicircular, or elliptical shape in plan view.

In this way, in the jet nozzle 6G of embodiment 8, by changing the planar shape of the notch 49 to have the same opening area as a rectangular notch but with a larger notch width on the upper side, it is possible to discharge large debris while maintaining the same solder flow rate.

<Ninth Embodiment>
15 is a side view of the soldering apparatus according to the ninth embodiment during partial soldering. In the soldering apparatus shown in Fig. 15, a lower end expanded portion 20 is provided at the lower end of the jet nozzle 6A on the side opposite to the circuit board 3.

The bottom flared section 20 is provided to enlarge the opening at the bottom of the jet nozzle 6A, and has a flared shape with a flared angle of 45 to 60 degrees. The provision of the bottom flared section 20 allows for a larger cross-sectional area compared to the straight jet nozzle 6A alone, reducing pressure loss when supplying solder from the solder bath 200 and ensuring a sufficient height for the solder to be sprayed even when the jet nozzle 6A has a low solder spraying capacity. Furthermore, the bottom flared section 20 contacts the solder dropping from the longitudinal notch 4 and lateral notch 5 of the jet nozzle 6A and diagonally deflects the solder, preventing solder from splashing and reducing solder adhesion to the circuit board 3.

In this way, in the soldering device of embodiment 9, by providing a lower end expansion section 20 at the lower end of the jet nozzle 6A, pressure loss during solder supply is reduced and the solder can be jetted to a sufficient height even when the jet nozzle 6A has a low solder jetting capacity. Furthermore, because the solder falling from the notch comes into contact with the lower end expansion section 20 and is deflected at an angle, solder does not splash and solder adhesion to the circuit board 3 can be reduced.

2, 2A, 2B, 2C: lead terminal; 3: circuit board; 4, 5, 41-49, 51: notch; 6, 6A-6G: jet nozzle; 7: molten solder; 14: recess; 20: lower end enlargement; 200: solder bath.

Claims (4)

A soldering device for soldering a plurality of lead terminals of an electronic component to a circuit board, comprising:
a solder bath containing molten solder;
a circulation mechanism for circulating the molten solder;
a jet nozzle that receives the molten solder from the circulation mechanism and ejects the molten solder into a jet,
The jet nozzle is
a plurality of side walls defining an opening through which the molten solder is ejected;
the circuit board, on which the electronic component is mounted so that the lead terminals pass through, is disposed above the opening, and at least one of the side walls among the plurality of side walls has at least one notch, the notch width and notch length of which are greater than the lead terminal width and length, at a position where the lead terminals face the at least one side wall when the lead terminals are inserted into the opening;
The opening has a rectangular shape in a plan view,
The plurality of side walls are
first and second longitudinal sidewalls of the opening;
a third side wall and a fourth side wall in a lateral direction of the opening,
The jet nozzle is
Among the plurality of side walls,
The first side wall has a plurality of first notches provided along the longitudinal direction,
the third side wall and the fourth side wall have a third notch and a fourth notch respectively provided along the short-side direction;
the second side wall has a plurality of second notches provided along the longitudinal direction;
The plurality of first notches provided in the first side wall of the jet nozzle include:
a central notch and two small notches provided on both sides of the central notch;
each of the plurality of second notches has the same opening area as each of the two small notches;
A soldering device in which the central notch has a larger notch width and a smaller notch length than each of the two small notches and each of the plurality of second notches, and its opening area is the same as the opening area of the plurality of second notches at a position facing the central notch . A soldering device for soldering a plurality of lead terminals of an electronic component to a circuit board, comprising:
a solder bath containing molten solder;
a circulation mechanism for circulating the molten solder;
a jet nozzle that receives the molten solder from the circulation mechanism and ejects the molten solder into a jet,
The jet nozzle is
a plurality of side walls defining an opening through which the molten solder is ejected;
the circuit board, on which the electronic component is mounted so that the lead terminals pass through, is disposed above the opening, and at least one of the side walls among the plurality of side walls has at least one notch, the notch width and notch length of which are greater than the lead terminal width and length, at a position where the lead terminals face the at least one side wall when the lead terminals are inserted into the opening;
The opening has a rectangular shape in a plan view,
The plurality of side walls are
first and second longitudinal sidewalls of the opening;
a third side wall and a fourth side wall in a lateral direction of the opening,
The jet nozzle is
Among the plurality of side walls,
The first side wall has a plurality of first notches provided along the longitudinal direction,
The plurality of lead terminals are
It has multiple types of lead terminals with different terminal widths,
the plurality of first notches provided on at least the first side wall of the jet nozzle have notch widths that match terminal widths of the plurality of types of lead terminals. The jet nozzle is
3. The soldering device according to claim 1, wherein each of the plurality of first notches provided on at least the first side wall has a notch shape in which the notch width is larger on the upper side facing the circuit board and smaller on the lower side. a lower end enlarged portion provided at a lower end of the jet nozzle opposite to the circuit board and enlarging an opening at the lower end;
3. The soldering apparatus according to claim 1, wherein the bottom enlarged portion has a shape that flares out at an angle of 45 degrees to 60 degrees.