Soldering nozzle, soldering device, and circuit board manufacturing method

Abstract

To provide a soldering nozzle, a soldering device, and a circuit board manufacturing method capable of stably bringing molten solder into contact with a soldering target.SOLUTION: A soldering nozzle 20 includes: a nozzle body 30 which has an opening 31 at an upper portion for jetting molten solder 60 upward for soldering, an inlet 32 for allowing the molten solder 60 to flow in and an outlet 33 for allowing the molten solder 60 to flow out at a lower portion, and forming a flow path 61 for the molten solder 60 therein; and a partition wall 40 which is provided inside the nozzle body 30, and partitions the flow path 61 into an inflow passage 62 communicating from the inlet 32 to the opening 31 and an outflow passage 63 communicating from the opening 31 to the outlet 33. A plating 50 having good wettability with respect to the molten solder 60 is formed on an inner wall surface forming the outflow passage 63.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a soldering nozzle, a soldering device, and a method for manufacturing a circuit board. [Background technology]

[0002] One soldering method is the wave soldering method, in which the object to be soldered is immersed in molten solder. In this method, molten solder is jetted upward from a soldering nozzle, and the jet solder is brought into contact with an electronic component inserted into a through-hole in a printed wiring board, for example.

[0003] In the jet soldering method, the molten solder jetted upward from the opening of the soldering nozzle takes on an upward convex shape in cross section. In particular, in soldering nozzles made of a material with low wettability to the molten solder, the molten solder exerts surface tension on the inner wall surface of the soldering nozzle, preventing contact between the upper edge of the inner wall surface and the molten solder. This results in a difference in the height of the molten solder jet between the center and edges of the soldering nozzle opening. If the difference in the height of the molten solder jet is large, sufficient solder can be supplied to the workpiece at the center of the soldering nozzle, but not at the edges. This results in insufficient soldering, resulting in incomplete soldering.

[0004] Patent Document 1 discloses a soldering device in which the upper end of the inner wall surface of the soldering nozzle is covered with a strip-shaped member that has good wettability with molten solder to eliminate instability in soldering caused by the surface tension of the molten solder preventing the upper end of the inner wall surface of the soldering nozzle from coming into contact with the molten solder. The soldering nozzle of Patent Document 1 includes a nozzle body (outer wall) with an opening at the top and a partition wall, and the nozzle body and the partition wall form an inlet channel (molten solder discharge portion) and an outlet channel (molten solder recovery portion). The molten solder flowing inside the soldering nozzle of Patent Document 1 flows from the inlet channel, over the partition wall, and into the outlet channel. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-066286 Summary of the Invention [Problem to be solved by the invention]

[0006] In the soldering apparatus of Patent Document 1, the inner wall surface of the soldering nozzle, except for the upper end, is made of a material with poor wettability to molten solder. That is, most of the inner wall surface and partition wall of the nozzle body that form the inlet and outlet channels have poor wettability to molten solder. When the inner wall surface and partition wall of the nozzle body that form the inlet and outlet channels have poor wettability to molten solder, the molten solder flowing through the inlet and outlet channels experiences significant resistance to the flow direction of the molten solder, resulting in a slower flow rate. In particular, the molten solder flowing through the outlet channel, which is the latter half of the molten solder flow path, flows at a slower rate than the molten solder flowing through the inlet channel due to the cumulative effect of resistance to the flow direction of the molten solder. Therefore, in the soldering nozzle of Patent Document 1, the flow rate of the molten solder flowing through the inlet channel differs significantly from the flow rate of the molten solder flowing through the outlet channel. This difference in flow rate causes the molten solder to stagnate at the opening, resulting in a large difference in the height of the molten solder jet between the center and end of the soldering nozzle. Furthermore, if there is a large difference in the height of the molten solder jet between the center and end portions of the soldering nozzle, there is a problem in that the molten solder cannot be brought into stable contact with the object to be soldered.

[0007] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a soldering nozzle, a soldering device, and a method for manufacturing a circuit board that can stably bring molten solder into contact with an object to be soldered. [Means for solving the problem]

[0008] The soldering nozzle according to the present disclosure comprises a nozzle body having an opening at the top for jetting molten solder upward to perform soldering, an inlet for letting the molten solder flow in, and an outlet at the bottom for letting the molten solder flow out, and forming an internal flow path for the molten solder; and a partition wall provided inside the nozzle body that divides the flow path into an inlet path that connects from the inlet to the opening, and an outlet path that connects from the opening to the outlet, and a plating that has good wettability to the molten solder is formed on the inner wall surface that forms the outlet path.

[0009] The soldering apparatus according to the present disclosure comprises a solder tank in which molten solder is stored, a duct having an intake port through which the molten solder flows, a nozzle plate attached to the duct, the soldering nozzle attached to the nozzle plate, and a circulation mechanism that supplies the molten solder to the soldering nozzle via the duct.

[0010] The method for manufacturing a circuit board according to the present disclosure uses the soldering device described above to jet molten solder from the soldering nozzle described above to solder a circuit board. [Effects of the Invention]

[0011] The soldering nozzle, soldering apparatus, and method for manufacturing a circuit board according to the present disclosure enable the molten solder to be brought into stable contact with the object to be soldered. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a front view schematically showing a soldering apparatus according to a first embodiment of the present disclosure. [Figure 2] 1 is a perspective view schematically illustrating a soldering nozzle according to a first embodiment of the present disclosure. [Figure 3] 1 is a cross-sectional view schematically illustrating a soldering nozzle according to a first embodiment of the present disclosure. [Figure 4] 1 is a plan view schematically showing a soldering nozzle according to a first embodiment of the present disclosure. [Figure 5]FIG. 10 is a plan view schematically showing a soldering nozzle according to a modified example of the first embodiment of the present disclosure. [Figure 6] FIG. 10 is a plan view schematically showing a soldering nozzle according to a modified example of the first embodiment of the present disclosure. [Figure 7] FIG. 10 is a plan view schematically showing a soldering nozzle according to a modified example of the first embodiment of the present disclosure. [Figure 8] FIG. 10 is a cross-sectional view schematically showing a soldering nozzle according to a modified example of the first embodiment of the present disclosure. [Figure 9] FIG. 10 is a cross-sectional view schematically showing a soldering nozzle according to a second embodiment of the present disclosure. [Figure 10] FIG. 10 is a cross-sectional view schematically showing a soldering nozzle according to a modified example of the second embodiment of the present disclosure. [Figure 11] FIG. 10 is a cross-sectional view schematically showing a soldering nozzle according to a third embodiment of the present disclosure. [Figure 12] FIG. 1 is a cross-sectional view schematically showing a conventional soldering nozzle. DETAILED DESCRIPTION OF THE INVENTION

[0013] An example of a soldering nozzle, a soldering apparatus, and a method for manufacturing a circuit board according to the present disclosure will be described below with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and their description will not be repeated.

[0014] Embodiment 1 <Configuration of the soldering device according to the first embodiment> First, the configuration of a soldering apparatus 10 according to a first embodiment of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a front view schematically showing the soldering apparatus 10. In Fig. 1, the flow path of molten solder 60 is indicated by outline arrows.

[0015] The soldering device 10 is a device that jets molten solder 60 upward from a soldering nozzle 20 and brings the molten solder 60 into contact with an object to be soldered, thereby performing soldering. As shown in Fig. 1, the soldering device 10 includes a solder bath 11, a duct 12, a nozzle plate 13, the soldering nozzle 20, a circulation mechanism 14, and a heater 18. The circulation mechanism 14 is composed of a motor 15, a motor shaft 16, and a pump 17.

[0016] Solder bath 11 is a hollow case with at least a portion of the top surface open. A heater 18 is arranged around the periphery of solder bath 11, and heater 18 keeps the temperature inside solder bath 11 above the melting point of the solder. Molten solder 60 is stored inside solder bath 11.

[0017] A duct 12, a motor shaft 16, and a pump 17 are arranged inside the solder bath 11. The duct 12 has a duct opening 12a formed above the liquid surface of the molten solder 60 stored inside the solder bath 11, and an intake port (not shown) formed in the liquid molten solder 60. The intake port of the duct 12 is formed so that the molten solder 60 can flow in, and the molten solder 60 is stored inside the duct 12.

[0018] A nozzle plate 13 is attached to the surface of the duct 12 on which the duct opening 12a is formed. A soldering nozzle 20 is attached to the nozzle plate 13 so as to protrude upward from the open upper surface of the solder bath 11. The nozzle plate 13 also has a through hole 13a formed so as to overlap with an inlet 32 ​​that the soldering nozzle 20 has at its bottom. The soldering nozzle 20 communicates with the interior of the duct 12 via the through hole 13a of the nozzle plate 13 and the inlet 32 ​​of the soldering nozzle 20.

[0019] The circulation mechanism 14 is composed of a motor 15, a motor shaft 16, and a pump 17, and supplies molten solder 60 to the soldering nozzle 20 via the duct 12. The pump 17 is driven by the motor 15, which is disposed outside the solder bath 11. More specifically, when the motor 15 is driven, the pump 17 receives the driving force of the motor 15 via the motor shaft 16, causing an impeller (not shown) of the pump 17 to rotate. When the circulation mechanism 14 is driven, the molten solder is supplied to the soldering nozzle 20 via the duct 12. More specifically, when the circulation mechanism 14 is driven, the molten solder 60 begins to circulate inside the solder bath 11, and the molten solder 60 is pressure-fed to the duct 12. The molten solder 60 passes through the duct 12 and is jetted upward from the soldering nozzle 20.

[0020] The molten solder 60 is, for example, a Sn (tin)-Ag (silver)-Cu (copper) based solder material. The solder bath 11, duct 12, nozzle plate 13, soldering nozzle 20, and circulation mechanism 14, which come into contact with the molten solder 60, are made of a material that does not dissolve in the molten solder. The material that does not dissolve in the molten solder is, for example, stainless steel.

[0021] <Configuration of soldering nozzle according to first embodiment> Next, the configuration of the soldering nozzle 20 according to the first embodiment of the present disclosure will be described with reference to Figures 2, 3, and 4. Figures 2, 3, and 4 are schematic diagrams of the soldering nozzle 20. Figure 2 is a perspective view, Figure 3 is a cross-sectional view taken along line AA in Figure 2, and Figure 4 is a plan view seen from above. In Figure 3, the flow path of the molten solder 60 is indicated by solid arrows.

[0022] As shown in FIG. 2, the soldering nozzle 20 includes a nozzle body 30 and a partition wall 40 . The nozzle body 30 is a hollow housing having an opening 31 at the top and an inlet 32 ​​and an outlet 33 at the bottom. More specifically, the nozzle body 30 is composed of an inlet peripheral wall portion 30a that forms the inlet 32 ​​and an outlet peripheral wall portion 30b that forms the outlet 33. The opening 31 is formed so that the molten solder 60 can be jetted upward from the soldering nozzle 20 to perform soldering. The inlet 32 ​​is formed so that the molten solder 60 can flow into the soldering nozzle 20. The outlet 33 is formed so that the molten solder 60 can flow out from the soldering nozzle 20.

[0023] 3, the inlet 32 ​​has an opening area equivalent to that of the through-hole 13a of the nozzle plate 13. The soldering nozzle 20 is arranged so that the inlet 32 ​​overlaps with the through-hole 13a of the nozzle plate 13. The inlet 32 ​​causes the molten solder 60 to flow from the duct 12 into the soldering nozzle 20 via the through-hole 13a of the nozzle plate 13.

[0024] The outlet 33 is provided above the inlet 32. In other words, the nozzle body 30 is formed so that the lower end of the outlet peripheral wall portion 30b is positioned above the lower end of the inlet peripheral wall portion 30a. Because the outlet 33 is provided above the inlet 32, there is a gap d between the outlet 33 and the nozzle plate 13. The outlet 33 is configured so that the molten solder 60 flowing out from the outlet 33 flows down the gap d between the outlet 33 and the nozzle plate 13, flows along the upper surface of the nozzle plate 13, and returns to the solder bath 11.

[0025] Furthermore, the opening area of ​​the outlet 33 is set to be 15% to 50% of the opening area of ​​the inlet 32. If the opening area of ​​the outlet 33 is less than 15% of the opening area of ​​the inlet 32, the amount of molten solder 60 flowing out from the soldering nozzle 20 will be less than the amount of molten solder 60 flowing into the soldering nozzle 20, and the jet height of the molten solder 60 will be unstable. If the opening area of ​​the outlet 33 is more than 50% of the opening area of ​​the inlet 32, the amount of molten solder 60 flowing out from the soldering nozzle 20 will be greater than the amount of molten solder 60 flowing into the soldering nozzle 20, and the jet height of the molten solder 60 will be unstable.

[0026] The shape of the opening 31 is formed to match the soldering area of ​​the object to be soldered. For example, as shown in Fig. 4, the opening 31 is configured to be rectangular in plan view. Therefore, the opening 31 has long sides 31a and short sides 31b. In other words, the dimension of the opening 31 in the longitudinal direction D1 is greater than the dimension of the opening 31 in the lateral direction D2. The inlet 32 ​​and the outlet 33 are configured to be rectangular in plan view and are arranged side by side in the lateral direction D2 of the opening 31.

[0027] As shown in FIG. 3 , a flow path 61 for molten solder 60 is formed inside the nozzle body 30. The flow path 61 is divided into an inlet path 62 and an outlet path 63 by a partition wall 40 provided inside the nozzle body 30. The inlet path 62 is a flow path that connects the inlet 32 ​​to the opening 31 and allows the molten solder 60 to jet upward from the opening 31. The inlet path 62 is formed by the inlet peripheral wall 30a and the partition wall 40. The outlet path 63 is a flow path that connects the opening 31 to the outlet 33 and allows the molten solder 60 to flow out from the outlet 33. The outlet path 63 is formed by the outlet peripheral wall 30b and the partition wall 40. Here, the partition wall 40 and a portion of the inlet peripheral wall 30a of the nozzle body 30 are provided continuously.

[0028] 4, the partition wall 40 is provided inside the nozzle body 30 and is parallel to the long side 31a of the opening 31 in a plan view. In other words, the partition wall 40 divides the flow path 61 into the inflow path 62 and the outflow path 63 so that the inflow path 62 and the outflow path 63 are aligned in the short-side direction D2 of the opening 31.

[0029] 3, the partition wall 40 is provided such that the upper surface 41 of the partition wall 40 is lower than the upper surface 34 of the nozzle body 30. By configuring the partition wall 40 so that the upper surface 41 is lower than the upper surface 34 of the nozzle body 30, a flow path 61 for the molten solder 60 can be formed inside the nozzle body 30 without causing the molten solder 60 to overflow outside the nozzle body 30. Because the molten solder 60 is not allowed to overflow outside the nozzle body 30, it is possible to prevent the molten solder 60 from coming into contact with areas outside the soldering range of the object to be soldered.

[0030] On the inner wall surface that forms the outflow path 63, plating 50 having good wettability with respect to molten solder 60 is formed. In detail, plating 50 having good wettability with respect to molten solder 60 is formed on the inner surface of the outlet peripheral wall portion 30b and on the surface of the partition wall 40 that faces the outlet peripheral wall portion 30b. Here, wettability is a property that indicates how well a liquid spreads on a solid surface, and good wettability indicates a state in which the contact angle, which is the angle between the liquid and the solid, is small and the liquid easily spreads on the solid surface.

[0031] By forming plating 50, which has good wettability to molten solder 60, on the inner wall surface that forms outlet path 63, the resistance experienced by molten solder 60 flowing through outlet path 63 is reduced, and the flow rate of molten solder 60 flowing through outlet path 63 can be prevented from slowing down. If the flow rate of molten solder 60 flowing through outlet path 63 slows down and a difference in flow rate of molten solder 60 flowing through inlet path 62 and outlet path 63 occurs, the difference in flow rate causes molten solder to accumulate at opening 31, resulting in a difference in the height of the molten solder jet at the center and end of soldering nozzle 20. In soldering nozzle 20, plating 50 formed on the inner wall surface that forms outlet path 63 prevents the flow rate of molten solder 60 flowing through outlet path 63 from slowing down, thereby reducing the difference in flow rate of molten solder 60 flowing through inlet path 62 and outlet path 63. Therefore, in the soldering nozzle 20, the difference in the jet height of the molten solder 60 between the center and the ends of the soldering nozzle 20 can be reduced.

[0032] An example of the plating 50 that has good wettability with the molten solder 60 is Ni (nickel) plating. Ni plating is a plating that has good wettability with the molten solder 60. Furthermore, Ni plating is a metal plating that has a higher melting point than the molten solder 60 and is unlikely to form an intermetallic compound with the molten solder 60, and therefore does not dissolve in the molten solder 60. Therefore, by forming Ni plating on the inner wall surface that forms the outflow path 63, it is possible to obtain the long-term effect of suppressing a slowdown in the flow rate of the molten solder 60 flowing through the outflow path 63. In other words, Ni plating that does not dissolve in the molten solder 60 can extend the life of the plating 50 and reduce maintenance costs compared to metal plating that dissolves in the molten solder 60.

[0033] <Operation of the soldering device according to the first embodiment> Next, the operation of the soldering apparatus 10 according to the first embodiment of the present disclosure will be described with reference to FIGS.

[0034] 1, molten solder 60 stored in solder tank 11 flows into duct 12 through an intake port (not shown) provided in duct 12. When circulation mechanism 14 is driven, molten solder 60 that has flowed into duct 12 from the intake port passes through the inside of duct 12 and is supplied toward soldering nozzle 20.

[0035] 3, the molten solder 60 that has passed through the duct 12 is supplied to the soldering nozzle 20 from the inlet 32 ​​of the soldering nozzle 20. The molten solder 60 that has flowed into the soldering nozzle 20 from the inlet 32 ​​flows through a flow path 61 for the molten solder 60, which flows from an inlet channel 62 to an outlet channel 63. More specifically, the molten solder 60 flows upward through the inlet channel 62 from the inlet 32 ​​toward the opening 31, and then flows downward through the outlet channel 63 from the opening 31 toward the outlet 33 via the upper surface 41 of the partition wall 40. In this way, the flow path 61 for the molten solder 60 formed by the nozzle body 30 and the partition wall 40 causes the molten solder 60 to jet upward from the opening 31.

[0036] <Method of Manufacturing Circuit Board According to First Embodiment> Next, a method for manufacturing a circuit board using the soldering apparatus 10 according to the first embodiment of the present disclosure will be described. As an example of the method for manufacturing a circuit board using the soldering apparatus 10, a process for soldering a printed wiring board 70 will be mainly described with reference to FIG.

[0037] 3, printed wiring board 70, which is the object to be soldered, is composed of substrate 71 and component 72. Substrate 71 has through-hole 73, and component 72 has lead terminals 74a, 74b, and 74c. Substrate 71 is, for example, glass cloth impregnated with epoxy resin.

[0038] First, a printed wiring board 70 is prepared in which lead terminals 74a, 74b, and 74c of a component 72 are inserted into through holes 73 formed in a substrate 71. Next, flux is applied to the underside of the printed wiring board 70 using a spray fluxer (not shown). After the flux has been applied, the printed wiring board 70 is placed above the soldering nozzle 20. Here, the printed wiring board 70 is placed with its underside facing downward so that soldering is performed on the underside to which the flux has been applied.

[0039] Molten solder 60 is jetted from the soldering nozzle 20 of the soldering apparatus 10 to solder the printed wiring board 70. Here, the difference in jet height of the molten solder 60 jetted from the opening 31 of the soldering nozzle 20 is reduced between the center and the ends of the soldering nozzle 20. Therefore, the molten solder 60 can be brought into contact with the lead terminal 74a located in the center of the soldering nozzle 20 and 74b, 74c located at the ends of the soldering nozzle 20 at a stable jet height, and a sufficient amount of solder can be supplied.

[0040] <Effects of the First Embodiment> The functions and effects of the soldering nozzle 20, the soldering apparatus 10, and the method for manufacturing a circuit board according to the first embodiment of the present disclosure will be described in comparison with conventional examples.

[0041] First, a soldering nozzle 2 provided in a conventional soldering apparatus will be described with reference to Fig. 12. As shown in Fig. 12, the conventional soldering nozzle 2 differs from the soldering nozzle 20 of the first embodiment of the present disclosure in the location where the plating 50, which has good wettability with the molten solder 60, is formed. In the conventional soldering nozzle 2, the plating 50, which has good wettability with the molten solder 60, is formed on the upper end of the inner wall surface of the nozzle body 3. Furthermore, the nozzle body 3 and the partition wall 4 are made of a material that has poor wettability with the molten solder 60. That is, in the conventional soldering nozzle 2, most of the inner wall surfaces that form the inlet channel 62 and the outlet channel 63 are made of a material that has poor wettability with the molten solder 60.

[0042] In the flow path 61 of the molten solder 60, if the wettability of the surface in contact with the molten solder 60 to the molten solder 60 is poor, the flow rate of the molten solder 60 will be slower than if the wettability is good. This is because the flow rate is significantly affected by the interfacial tension acting between the molten solder 60 and the contact surface with the molten solder 60. Interfacial tension is a force that causes molecules on the surface of a material to attempt to reduce their surface area due to intermolecular forces, and occurs at the interface between the liquid phase and the solid phase. Here, the liquid phase is the molten solder 60, and the solid phase is the contact surface with the molten solder 60. The interfacial tension acting between the contact surface with the molten solder 60 and the molten solder 60 becomes large when the wettability of the surface in contact with the molten solder 60 to the molten solder 60 is poor, and acts as resistance to the flow direction of the molten solder 60.

[0043] In the conventional soldering nozzle 2, most of the inner wall surfaces forming the inlet channel 62 and the outlet channel 63 are made of a material that has poor wettability to the molten solder 60, so the flow rate of the molten solder 60 is slower than when the inner wall surfaces forming the inlet channel 62 and the outlet channel 63 have good wettability to the molten solder 60. In particular, in the outlet channel 63, which is the latter half of the flow path of the molten solder 60, the effect of interfacial tension is integrated, so the flow rate of the molten solder 60 in the outlet channel 63 is slower than the flow rate of the molten solder 60 in the inlet channel 62. If the difference in flow rate of the molten solder 60 in the inlet channel 62 and the outlet channel 63 becomes large, the molten solder 60 will stagnate in the opening 31 by the amount of the flow rate difference. Therefore, in the conventional soldering nozzle 2, most of the inner wall surfaces forming the outlet channel 63 are made of a material that has poor wettability to the molten solder 60, so the difference in jet height of the molten solder 60 between the center and end portions of the soldering nozzle 2 becomes large. If the difference in the jet height of the molten solder 60 between the center and end of the soldering nozzle 2 becomes large, the molten solder 60 cannot be brought into stable contact with the object to be soldered, and a sufficient amount of solder cannot be supplied to the object to be soldered.

[0044] In particular, if the output of the circulation mechanism 14 is increased to increase the flow rate of the molten solder 60 circulating through the soldering nozzle 2, the jet height of the molten solder 60 becomes even more unstable. A case where the flow rate of the molten solder 60 circulating through the soldering nozzle 2 is increased will be described. In the jet soldering method, when an object to be soldered is immersed in the molten solder 60 jetted from above the soldering nozzle 2, the object may lose heat from the molten solder 60, causing the temperature of the molten solder 60 to drop. A common solution to this drop in the temperature of the molten solder 60 is to increase the output of the circulation mechanism 14 and increase the flow rate of the molten solder 60 circulating inside the soldering nozzle 2. However, if the flow rate of the molten solder 60 is increased, the velocity gradient between the wall side and the center side of the flow path becomes larger for the molten solder 60 flowing through the inlet channel 62 and the outlet channel 63, and the molten solder 60 experiences even greater resistance than when the flow rate is slow. Therefore, if the output of the circulation mechanism 14 is increased to speed up the flow rate of the molten solder 60 circulating through the soldering nozzle 2, the difference between the flow rate of the molten solder 60 in the inlet path 62 and the flow rate of the molten solder 60 in the outlet path 63 becomes even larger, and the jet height of the molten solder 60 becomes unstable.

[0045] In contrast, the soldering nozzle 20 according to the first embodiment of the present disclosure comprises a nozzle body 30 having an opening 31 at the top for jetting the molten solder 60 upward to perform soldering, an inlet 32 ​​for allowing the molten solder 60 to flow in, and an outlet 33 at the bottom for allowing the molten solder 60 to flow out, and forming a flow path for the molten solder 60 inside; and a partition wall 40 provided inside the nozzle body 30, which divides the flow path 61 into an inlet channel 62 that connects the inlet 32 ​​to the opening 31, and an outlet channel 63 that connects the opening 31 to the outlet 33; and a plating 50 that has good wettability to the molten solder 60 is formed on the inner wall surface that forms the outlet channel 63.

[0046] According to the soldering nozzle 20 of the first embodiment of the present disclosure, by forming a plating 50 having good wettability with respect to the molten solder 60 on the inner wall surface forming the outlet path 63, it is possible to suppress the influence of interfacial tension and prevent the flow rate of the molten solder 60 from slowing down. Therefore, according to the soldering nozzle 20 of the first embodiment of the present disclosure, it is possible to suppress the difference in the flow rate of the molten solder 60 in the inlet path 62 and the outlet path 63, and it is possible to suppress the difference in the jet height of the molten solder 60 between the center and the ends of the soldering nozzle 20. Furthermore, according to the soldering nozzle 20 of the first embodiment of the present disclosure, it is possible to suppress the difference in the jet height of the molten solder 60 between the center and the ends of the soldering nozzle 20, so that the molten solder 60 can be brought into stable contact with the workpiece to be soldered, for example, a printed wiring board 70, and a sufficient amount of solder can be supplied to the printed wiring board 70.

[0047] According to the soldering nozzle 20 of the first embodiment of the present disclosure, the influence of interfacial tension can be suppressed, and therefore, even when the output of the circulation mechanism 14 is increased to speed up the flow rate of the molten solder 60, a slowdown in the flow rate of the molten solder 60 can be suppressed. Therefore, according to the soldering nozzle 20 of the first embodiment of the present disclosure, even when the output of the circulation mechanism 14 is increased to speed up the flow rate of the molten solder 60, a difference in the jet height of the molten solder 60 between the center and the ends of the soldering nozzle 20 can be suppressed, and the molten solder 60 can be brought into stable contact with the object to be soldered, for example, the printed wiring board 70.

[0048] Furthermore, the plating 50 that is provided in the soldering nozzle 20 according to the first embodiment of the present disclosure and that has good wettability with the molten solder 60 is a metal plating that does not dissolve in the molten solder 60. Therefore, with the soldering nozzle 20 according to the first embodiment of the present disclosure, the effects of the plating 50 that has good wettability with the molten solder 60 can be obtained over a long period of time. Furthermore, compared to metal plating that dissolves in the molten solder 60, the life of the plating 50 can be extended, and maintenance costs can be reduced.

[0049] In the present embodiment, an example has been shown in which Ni (nickel) plating, which does not dissolve in molten solder 60, is formed as plating 50 that has good wettability with molten solder 60, but the present invention is not limited to this. Plating 50 is preferably a metal that does not dissolve in molten solder 60, but any plating that has good wettability with molten solder 60 will do. For example, plating 50 may be Sn (tin) plating, Au (gold) plating, Ag (silver) plating, or Cu (copper) plating.

[0050] Furthermore, in this embodiment, an example has been shown in which the opening 31 is configured to have a rectangular shape in a plan view, but this is not limited to this. The shape of the opening 31 may be formed to match the soldering area of ​​the object to be soldered. As shown in Figure 5, the shape of the opening 31 in a plan view may be a square (Figure 5(a)), a circle (Figure 5(b)), an L-shape (Figure 5(c)), etc.

[0051] In the present embodiment, an example has been shown in which the opening 31 is rectangular in plan view and the partition wall 40 is provided inside the nozzle body 30 parallel to the long side 31a of the opening 31 in plan view, but the present invention is not limited to this. The partition wall 40 may be provided inside the nozzle body 30 and may divide the flow path 61 of the molten solder 60 into an inlet channel 62 and an outlet channel 63. As shown in FIG. 6 , the partition wall 40 may be provided parallel to the short side 31b of the opening 31 and may divide the flow path 61 into the inlet channel 62 and the outlet channel 63 so that the inlet channel 62 and the outlet channel 63 are aligned in the longitudinal direction D1 of the opening 31.

[0052] In the present embodiment, an example of the soldering nozzle 20 has been shown in which one partition wall 40 is provided inside the nozzle body 30, and one outflow path 63 that connects the opening 31 to one outflow port 33 is formed by the nozzle body 30 and the one partition wall 40. However, the soldering nozzle 20 may also have a plurality of partition walls 40 provided inside the nozzle body 30, and a plurality of outflow paths 63 that connect the opening 31 to a plurality of outflow ports 33, respectively, formed by the nozzle body 30 and the plurality of partition walls 40. Here, a modified example of the soldering nozzle 20 in which two partition walls 40a, 40b are provided inside the nozzle body 30, and two outlet paths 63a, 63b that respectively connect the opening 31 and the two outlet ports 33a, 33b are formed by the nozzle body 30 and the two partition walls 40a, 40b will be described with reference to Figures 7 and 8. Figure 7 is a plan view of the modified example of the soldering nozzle 20 as seen from above, and Figure 8 is a cross-sectional view showing the cross section of the modified example of the soldering nozzle 20 corresponding to the line segment AA in Figure 2.

[0053] 7 and 8, the modified example of the soldering nozzle 20 includes a nozzle body 30 having one opening 31 at an upper portion, one inlet 32, and two outlets 33a, 33b at a lower portion, and two partition walls 40a, 40b provided inside the nozzle body 30. The opening 31 of the nozzle body 30 has a rectangular shape in a plan view, and the two outlets 33a, 33b are adjacent to each other in the short-side direction D2 of the opening 31, with the inlet 32 ​​sandwiched between them. The two partition walls 40a, 40b are provided inside the nozzle body 30, parallel to the long side 31a of the opening 31 in a plan view. The two partition walls 40a, 40b divide a flow path 61 for molten solder 60 into one inlet channel 62 connecting one inlet 32 ​​and one opening 31, and two outlet channels 63a, 63b connecting one opening 31 and two outlets 33a, 33b, respectively. In other words, the two partition walls 40a, 40b divide the flow path 61 so that the two outlet channels 63a, 63b are adjacent to each other across the inlet channel 62 in the short-side direction D2 of the opening 31 in a plan view. The inlet channel 62 is formed by the inlet peripheral wall 30a and the two partition walls 40a, 40b. One of the two outlet channels, the outlet channel 63a, is formed by the outlet peripheral wall 30b and one of the two partition walls, the partition wall 40a. The other of the two outflow paths, 63b, is formed by the outlet peripheral wall portion 30b and the other of the two partition walls, 40b.

[0054] If the position of the outlet path 63 from which the molten solder 60 flows is offset, a difference in jet height will occur between a position far from the outlet path 63 and a position close to the outlet path 63. According to the modified example of the soldering nozzle 20 shown in Figures 7 and 8, the molten solder 60 flowing in from the inlet path 62 is dispersed into two outlet paths 63a, 63b adjacent to each other on either side of the inlet path 62 before flowing out of the soldering nozzle 20, thereby making the jet height more stable. Therefore, according to the modified example of the soldering nozzle 20 shown in Figures 7 and 8, the molten solder 60 can be brought into more stable contact with the object to be soldered.

[0055] In this embodiment, an example has been shown in which the molten solder 60 is a Sn (tin)-Ag (silver)-Cu (copper) based solder material, but this is not limited to this, and the same effect as in this embodiment can be obtained even if a Sn (tin)-Cu (copper) based solder, Sn (tin)-Bi (bismuth) based solder, etc. is used.

[0056] In the present embodiment, the solder bath 11, duct 12, nozzle plate 13, soldering nozzle 20, and circulation mechanism 14 that come into contact with the molten solder 60 are made of stainless steel, but this is not a limitation. The solder bath 11, duct 12, nozzle plate 13, soldering nozzle 20, and circulation mechanism 14 that come into contact with the molten solder 60 may be made of any material that does not dissolve in the molten solder, such as titanium.

[0057] In this embodiment, printed wiring board 70 made of substrate 71 made of glass cloth impregnated with epoxy resin is used as an example of a circuit board manufactured using soldering apparatus 10, but the present invention is not limited to this. The circuit board manufactured using soldering apparatus 10 may also be a printed wiring board made of a substrate made of a glass composite substrate made by mixing glass cloth and glass nonwoven fabric and impregnated with epoxy resin.

[0058] Embodiment 2 In the first embodiment of the present disclosure, a soldering nozzle 20 was described in which plating 50 with good wettability to molten solder 60 was formed on the inner wall surface that forms the outflow path 63. In the second embodiment, a soldering nozzle 220 will be described in which plating 50 with good wettability to molten solder 60 is formed not only on the inner wall surface that forms the outflow path 63 but also on the upper surface 41 of the partition wall 40. In the second embodiment, the same components as those in the first embodiment of the present disclosure are denoted by the same reference numerals, and descriptions of the same or corresponding parts will be omitted. A soldering nozzle 220 according to the second embodiment will be described below with reference to the drawings. The second embodiment of the present disclosure relates to the soldering nozzle 220, a soldering apparatus equipped with the soldering nozzle 220, and a method for manufacturing a circuit board using the soldering apparatus.

[0059] The configuration of a soldering nozzle 220 according to a second embodiment of the present disclosure will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view that schematically shows a cross section of the soldering nozzle 220 corresponding to line segment AA in Fig. 2. In Fig. 9, the flow path of the molten solder 60 is indicated by solid arrows.

[0060] 9, in the soldering nozzle 220 according to the second embodiment, similarly to the soldering nozzle 20 according to the first embodiment, a plating 50 having good wettability with respect to the molten solder 60 is formed on the inner wall surface that forms the outflow path 63, i.e., the inner surface of the outlet peripheral wall 30b and the surface of the partition wall 40 that faces the outlet peripheral wall 30b. The soldering nozzle 220 further has a plating 50 formed on the upper surface 41 of the partition wall 40, the plating 50 having good wettability with respect to the molten solder 60.

[0061] According to the soldering nozzle 220 of the second embodiment, the area of ​​the plating 50 formed on the upper surface 41 of the partition wall 40 is increased compared to the soldering nozzle 20 of the first embodiment. Therefore, the molten solder 60 flowing inside the soldering nozzle 220 is less affected by the interfacial tension acting between the molten solder 60 and the surface in contact with the molten solder 60, compared to the molten solder 60 flowing inside the soldering nozzle 20 of the first embodiment, and a slowdown in the flow rate can be further suppressed. Therefore, according to the soldering nozzle 220 of the second embodiment, the difference between the flow rate of the molten solder 60 in the inlet channel 62 and the flow rate of the molten solder 60 in the outlet channel 63 can be further reduced, and the difference in the jet height of the molten solder 60 between the center and the ends of the soldering nozzle 20 can be further reduced, thereby enabling the molten solder 60 to stably contact the workpiece.

[0062] Furthermore, in the soldering nozzle 220, during soldering, similarly to the soldering nozzle 20 of the first embodiment, the molten solder 60 flows upward from the inlet 32 ​​toward the opening 31 through the inlet channel 62, then passes through the upper surface 41 of the partition wall 40, and flows downward from the opening 31 toward the outlet 33 through the outlet channel 63. Therefore, after soldering is completed, the molten solder 60 may remain on the upper surface 41 of the partition wall 40.

[0063] In the soldering nozzle 220 according to the second embodiment, the plating 50 having good wettability to the molten solder 60 is formed on the upper surfaces 41 of the partition walls 40, and therefore the molten solder 60 easily wets and spreads on the upper surfaces 41 of the partition walls 40. Therefore, after soldering is completed, the molten solder 60 adhering to the upper surfaces 41 of the partition walls 40 spreads and tends to flow downward along the side surfaces of the partition walls 40 due to gravity. Therefore, with the soldering nozzle 220 according to the second embodiment, the plating 50 having good wettability to the molten solder 60 formed on the upper surfaces 41 of the partition walls 40 can prevent the molten solder 60 from remaining on the upper surfaces 41 of the partition walls 40.

[0064] In this embodiment, the soldering nozzle 220 has been described in which the plating 50, which has good wettability to the molten solder 60, is formed on the inner wall surface forming the outlet channel 63 and the upper surface 41 of the partition wall 40. Furthermore, as shown in FIG. 10 , the plating 50, which has good wettability to the molten solder 60, may also be formed on the inner wall surface forming the inlet channel 62 that is located above the opening 31. The soldering nozzle 220 shown in FIG. 10 can further increase the area that is good for wettability to the molten solder 60, thereby further reducing the difference in flow velocity of the molten solder 60 in the inlet channel 62 and the outlet channel 63, and further reducing the difference in jet height of the molten solder 60 between the center and end portions of the soldering nozzle 20. This allows the molten solder 60 to stably contact the workpiece. Furthermore, in the soldering nozzle 220 shown in FIG. 10 , the plating 50 is formed within the same vertical dimensional range of the soldering nozzle 220. This facilitates the formation of the plating 50.

[0065] Embodiment 3 In the first embodiment of the present disclosure, a soldering nozzle 20 was described that includes a nozzle body 30 having an opening 31 at an upper portion, an inlet 32 ​​and an outlet 33 at a lower portion, with the outlet 33 being provided above the inlet 32. In the third embodiment, a soldering nozzle 320 will be described that includes a nozzle body 330 in which an upper nozzle body portion 330c, which is above the outlet 33, is provided in a removable manner. In the third embodiment, the same components as those in the first and second embodiments of the present disclosure are designated by the same reference numerals, and descriptions of the same or corresponding parts will be omitted. A soldering nozzle 320 according to the third embodiment will be described below with reference to the drawings. The third embodiment of the present disclosure relates to the soldering nozzle 320, a soldering apparatus equipped with the soldering nozzle 320, and a method for manufacturing a circuit board using the soldering apparatus.

[0066] The configuration of a soldering nozzle 320 according to a third embodiment of the present disclosure will be described with reference to Fig. 11. Fig. 11 is a cross-sectional view schematically showing a cross section of the soldering nozzle 320 corresponding to line segment AA in Fig. 2. Fig. 11(a) shows the state before the nozzle body upper part 330c constituting the nozzle body 330 is removed, and Fig. 11(b) shows the state after the nozzle body upper part 330c constituting the nozzle body 330 has been removed.

[0067] 11, the soldering nozzle 320 according to the third embodiment includes a nozzle body 330 including an upper nozzle body portion 330c located above the outlet 33 and a lower nozzle body portion 330d located below the outlet 33. The nozzle body 330 includes the upper nozzle body portion 330c and the lower nozzle body portion 330d that are detachable. For example, the lower surface of the upper nozzle body portion 330c and the upper surface of the lower nozzle body portion 330d are formed with matable concave-convex portions.

[0068] Similar to the nozzle body 30 according to the first embodiment, the nozzle body 330 is made up of an inlet peripheral wall portion 30a that forms the inlet 32 ​​and an outlet peripheral wall portion 30b that forms the outlet 33. In other words, the inlet peripheral wall portion 30a is made up of a part of the nozzle body upper portion 330c that is above the outlet 33, and a nozzle body lower portion 330d that is below the outlet 33. The outlet peripheral wall portion 30b is a portion of the nozzle body 330 that is located above the outlet 33 and is part of the nozzle body upper portion 330c.

[0069] As in the soldering nozzle 20 according to the first embodiment, a partition wall 40 is provided inside the nozzle body 330, and the partition wall 40 is provided continuous with a part of the inlet peripheral wall 30a that constitutes the nozzle body 330. In detail, the partition wall 40 is provided in the nozzle body upper part 330c of the nozzle body 330, and the partition wall 40 is provided continuous with a part of the inlet peripheral wall 30a that is the nozzle body lower part 330d of the nozzle body 330. The partition wall 40 and a part of the inlet peripheral wall 30a, which is the nozzle main body lower part 330d, are provided so as to be removable. For example, a matable concave-convex portion is formed on the lower surface of the partition wall 40 and the upper surface of the part of the inlet peripheral wall 30a, which is the nozzle main body lower part 330d.

[0070] As with the soldering nozzle 20 of the first embodiment, the inner wall surfaces forming the outflow path 63 are formed with a plating 50 that has good wettability with the molten solder 60. In detail, the plating 50 is formed on the inner surface of the outlet peripheral wall 30b that is part of the nozzle body upper part 330c, and on the surface of the partition wall 40 provided on the nozzle body upper part 330c that faces the outlet peripheral wall 30b.

[0071] The soldering nozzle 320 according to the third embodiment has a removable nozzle body upper part 330c. Therefore, the nozzle body upper part 330c, which has a surface on which the plating 50 is formed, is removable from the nozzle body lower part 330d, which facilitates maintenance work when the plating 50 deteriorates. Furthermore, because only the portion of the soldering nozzle 320 having the surface on which the plating 50 is formed can be replaced, maintenance costs can be reduced compared to replacing the entire soldering nozzle 320.

[0072] Although the present disclosure has been described above based on the embodiments, the present disclosure is not limited to the embodiments. Furthermore, appropriate combinations, modifications, or omissions of the embodiments are also within the scope of the technical ideas shown in the embodiments.

[0073] Various aspects of the present disclosure are summarized below as appendices.

[0074] (Appendix 1) a nozzle body having an opening at an upper portion for jetting molten solder upward to perform soldering, an inlet for introducing the molten solder, and an outlet at a lower portion for discharging the molten solder, and forming a flow path for the molten solder inside; a partition wall provided inside the nozzle body and dividing the flow path into an inlet path communicating from the inlet to the opening and an outlet path communicating from the opening to the outlet; Equipped with A plating having good wettability with respect to the molten solder is formed on the inner wall surface forming the outflow path. Soldering nozzle. (Appendix 2) an upper surface of the partition wall is provided below an upper surface of the nozzle body, a plating having good wettability with respect to the molten solder is formed on the upper surface of the partition wall; 1. A soldering nozzle as described in Appendix 1. (Appendix 3) The outlet is provided above the inlet, The nozzle body has an upper portion above the outlet that is detachably provided. A soldering nozzle as described in either Appendix 1 or Appendix 2. (Appendix 4) The plating is a metal plating that does not dissolve in the molten solder. A soldering nozzle according to any one of appendixes 1 to 3. (Appendix 5) the nozzle body has the opening, the inlet, and the outlet, each of which has a rectangular shape; the partition wall is provided inside the nozzle body parallel to a side of the opening in a plan view and divides the flow path into the inlet channel and the outlet channel; 5. A soldering nozzle according to any one of appendixes 1 to 4. (Appendix 6) the nozzle body has two outlets adjacent to each other with the inlet in between in a direction of a side of the opening, The partition wall is provided inside the nozzle body in two pieces parallel to a side of the opening in a plan view, The two partition walls divide the flow path into the inlet channel and the two outlet channels. 1. A soldering nozzle as described in Appendix 5. (Appendix 7) a solder bath in which the molten solder is stored; a duct having an inlet formed therein through which the molten solder flows; a nozzle plate attached to the duct; a soldering nozzle according to any one of claims 1 to 6 attached to the nozzle plate; a circulation mechanism that supplies the molten solder to the soldering nozzle through the duct; A soldering device comprising: (Appendix 8) The soldering apparatus according to claim 7 is used to jet the molten solder from the soldering nozzle to solder a circuit board. A method for manufacturing a circuit board. [Explanation of symbols]

[0075] 10 Soldering equipment 11 Solder pot 12 Duct 12a Duct opening 13 Nozzle plate 13a Nozzle plate through hole 14 Circulation mechanism 15 Motor 16 Motor shaft 17 Pump 18 Heater 20 soldering nozzles 30 Nozzle body 30a Inlet peripheral wall 30b Outlet peripheral wall 30c Nozzle body upper part 30d Nozzle body bottom 31 Aperture 31a Long side 31b Short side 32 Inlet 33, 33a, 33b outlet 34 Top surface of nozzle body 40 Bulkhead 41 Top of bulkhead 50 Plating 60 molten solder 61 Flow path 62 Inflow channel 63, 63a, 63b Outflow channel 70 Printed wiring board 71 Base material 72 parts 73 through holes 74a, 74b, 74c Lead terminals D1 Longitudinal direction of opening D2 Short side of opening d gap

Claims

1. a nozzle body having an opening at an upper portion for jetting molten solder upward to perform soldering, an inlet for introducing the molten solder, and an outlet at a lower portion for discharging the molten solder, and forming a flow path for the molten solder inside; a partition wall provided inside the nozzle body and dividing the flow path into an inlet path communicating from the inlet to the opening and an outlet path communicating from the opening to the outlet; Equipped with A plating having good wettability with respect to the molten solder is formed on the inner wall surface forming the outflow path. Soldering nozzle.

2. an upper surface of the partition wall is provided below an upper surface of the nozzle body, a plating having good wettability with respect to the molten solder is formed on the upper surface of the partition wall; The soldering nozzle according to claim 1 .

3. The outlet is provided above the inlet, The nozzle body has an upper portion above the outlet that is detachably provided. The soldering nozzle according to claim 1 .

4. The plating is a metal plating that does not dissolve in the molten solder. The soldering nozzle according to claim 1 .

5. the nozzle body has the opening, the inlet, and the outlet, each of which has a rectangular shape; the partition wall is provided inside the nozzle body parallel to a side of the opening in a plan view and divides the flow path into the inlet channel and the outlet channel; The soldering nozzle according to claim 1 .

6. the nozzle body has the rectangular opening, the inlet, and two outlets; The two outlets are provided adjacent to each other with the inlet in between in the direction of the side of the opening, two partition walls are provided inside the nozzle body and parallel to sides of the opening in a plan view, The two partition walls divide the flow path into the inlet channel and the two outlet channels. The soldering nozzle according to claim 1 .

7. a solder bath in which the molten solder is stored; a duct having an inlet formed therein through which the molten solder flows; a nozzle plate attached to the duct; a soldering nozzle according to any one of claims 1 to 6 attached to the nozzle plate; a circulation mechanism that supplies the molten solder to the soldering nozzle through the duct; A soldering device comprising:

8. The soldering apparatus according to claim 7 is used to jet the molten solder from the soldering nozzle to solder a circuit board. A method for manufacturing a circuit board.

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