Nozzle and selective wave soldering apparatus suitable for blind soldering

Abstract

The application relates to a welding nozzle technical field, in particular to a nozzle and a selective wave peak welding device which can be applied to blind area welding. The nozzle has a main body section and a biasing part which protrudes from the side wall of the top end of the main body section. The top end of the nozzle has an upward opening ejection cavity. One side of the inside of the ejection cavity is a working area located at the top end of the biasing part, and the other side is a reflow area located at the top end of the main body section. The biasing part can enter the blind area, and the molten solder is ejected from the working area of the biasing part to perform welding operation on the welding area above the blind area, so that the interference of the blind area structure on welding is overcome, and selective wave peak welding of the blind area is realized. The gap of the reflow area forms a layout staggered with the working area, ensures that the molten solder of the reflow does not fall on the shielding surface of the blind area, avoids the pollution of the workpiece, reduces the contact opportunity of the molten solder with oxygen, prolongs the cleaning period of the nozzle, and saves the cost.

Description

Technical Field

[0001] This invention relates to the field of welding nozzle technology, and in particular to a nozzle suitable for blind zone welding, and also to a selective wave welding apparatus including the above-mentioned nozzle suitable for blind zone welding. Background Technology

[0002] In the field of PCB board soldering, selective wave soldering equipment is usually used for soldering operations. For example, Chinese Patent No. CN107252946A discloses a wave soldering furnace for wave soldering, which mainly uses a ring-shaped nozzle. During soldering, the center of the nozzle sprays a wave upward to solder the area. At the same time, the sprayed molten solder falls from the periphery of the nozzle and flows back into the solder pot.

[0003] However, when the nozzles of the aforementioned wave soldering oven are used to solder irregularly shaped workpieces, if the soldering area of ​​the irregularly shaped workpiece is in a narrow space (blind zone), it will be difficult to complete the soldering. Moreover, the molten solder flowing back during soldering is also likely to fall to the bottom of the narrow space of the workpiece, causing the workpiece to be contaminated. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that, in order to solve the problem that the nozzle of selective wave soldering in the prior art is difficult to weld the welding area of ​​irregular workpieces in a narrow space, and that the molten solder flowing back during welding is also easy to fall to the bottom of the narrow space of the workpiece, causing the workpiece to be contaminated, the present invention provides a nozzle that can be used for blind zone welding, and also provides a selective wave soldering device including the above-mentioned nozzle that can be used for blind zone welding.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a nozzle applicable to blind zone welding, the nozzle having a main body section and an offset part protruding from the side wall of the top of the main body section, the main body section having a channel for the flow of molten solder.

[0006] The nozzle has an upward-opening ejection chamber at its top end. One side of the ejection chamber is a working area located at the top of the biasing part, and the other side is a return flow area located at the top of the main body section. At least one side of the return flow area is provided with a notch.

[0007] The channel is connected to the work area and supplies molten solder to the work area;

[0008] The molten solder sprayed from above the work area is used to contact the welding area of ​​the workpiece for welding operations;

[0009] The working area and the reflow area are interconnected, allowing molten solder to flow from the working area to the reflow area and overflow outward through the notch.

[0010] Furthermore, the outer wall of the main body section has a downwardly extending guide groove on the side where the gap is located, and the upper end of the guide groove extends to the gap and communicates with the gap.

[0011] Furthermore, the direction from the working area to the recirculation area is the first direction, and the recirculation area has notches on both sides in the second direction. The second direction is perpendicular to the first direction. The outer walls on both sides of the main body section in the second direction have guide grooves. The upper end of the guide groove extends to the notch on its side and is connected to the notch on its side.

[0012] Furthermore, the bottom of the guide channel gradually slopes from top to bottom toward the centerline away from the return flow zone.

[0013] Furthermore, the bottom of the working area is a second bottom wall surface, the bottom of the recirculation area is a first bottom wall surface, and the height of the second bottom wall surface is lower than the height of the first bottom wall surface.

[0014] Furthermore, a dam is provided in the ejection chamber on the side where the gap is located. The height of the top end face of the dam is higher than the height of the first bottom wall, and the top end face of the dam defines the bottom of the gap.

[0015] Furthermore, the end of the second bottom wall away from the recirculation zone has a guide surface, which gradually slopes from top to bottom toward the centerline of the recirculation zone. The end of the guide surface away from the recirculation zone is connected to the side wall of the working area away from the recirculation zone through the third bottom wall. The height of the third bottom wall is higher than that of the second bottom wall, but lower than that of the first bottom wall.

[0016] Furthermore, the bottom end of the channel has an inlet for introducing molten solder into the channel, the top end of the channel sidewall has a lateral hole, the channel is connected to the bottom end of the working area through the lateral hole, and the lateral hole is arranged opposite to the guide surface.

[0017] Furthermore, it also includes a mounting base, which has a plug-in section, a positioning boss on the outer peripheral wall of the plug-in section, and a connecting hole inside;

[0018] The bottom end of the main body section has a root, and the root has a mounting hole that matches the insertion section. At least one positioning groove that matches the positioning boss is opened on the inner peripheral wall of the mounting hole.

[0019] The plug section is inserted into the mounting hole, and the positioning boss is located in the positioning groove. The connecting hole is connected to the entrance of the channel.

[0020] The present invention also provides a selective wave soldering apparatus, including the above-described nozzle suitable for blind zone soldering.

[0021] The beneficial effects of this invention are as follows: The nozzle of this invention, applicable to blind zone welding, is designed with a biasing part on the main body section, allowing the biasing part to enter the blind zone. Molten solder is ejected from the working area on the biasing part to perform welding operations on the welding area above the inside of the blind zone, thereby overcoming the interference of the blind zone structure on welding and realizing selective wave soldering in the blind zone. The notch of the reflow zone is staggered from the working area to ensure that the reflowing molten solder does not fall onto the shielding surface of the blind zone, avoiding workpiece contamination and reducing the chance of molten solder coming into contact with oxygen, thereby extending the nozzle cleaning cycle and saving costs.

[0022] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Figure 1 This is a three-dimensional schematic diagram of one side of the nozzle from which the present invention can be applied to blind zone welding;

[0025] Figure 2 This is a three-dimensional schematic diagram of the other side of the nozzle for blind zone welding, which is applicable to the present invention.

[0026] Figure 3 This is a cross-sectional schematic diagram of the nozzle for blind zone welding according to the present invention;

[0027] Figure 4 yes Figure 3 A magnified view of part A in the diagram;

[0028] Figure 5 This is a three-dimensional schematic diagram of the nozzle of the present invention, which is applicable to blind zone welding, performing selective wave soldering welding on the blind zone of the workpiece.

[0029] Figure 6 This is a cross-sectional schematic diagram of the nozzle of the present invention, which is applicable to blind zone welding, performing selective wave soldering welding on the blind zone of the workpiece.

[0030] In the figure: 1. Main body section, 101. Recirculation zone, 101a. First bottom wall surface, 102. Channel, 102a. Inlet, 102b. Side hole, 103. Notch, 104. Guide channel;

[0031] 2. Offset section, 201. Working area, 201a. Second bottom wall surface, 201b. Guide surface, 201c. Third bottom wall surface;

[0032] 3. Root, 301, mounting hole, 301a, positioning groove;

[0033] 4. Dams;

[0034] 5. Mounting base, 501. Plug-in section, 501a. Positioning boss, 501b. Connecting hole;

[0035] 6. Workpiece, 601. Transverse part, 601a. ​​Welding area, 602. Longitudinal part, 602a. Shielding surface, 603. Blind spot;

[0036] a1, first direction; b1, second direction; c1, centerline. Detailed Implementation

[0037] The invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention in a schematic manner. Therefore, they only show the components relevant to the invention, and the orientations and references (e.g., up, down, left, right, etc.) are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be limiting, and the scope of the claimed subject matter is defined solely by the appended claims and their equivalents.

[0038] like Figure 1-6 As shown, a nozzle applicable to blind zone soldering is provided. The nozzle has a main body section 1 and a biasing part 2 protruding from one side wall of the top of the main body section 1. The biasing part 2 is integrally formed and connected to the main body section 1. The main body section 1 can be, but is not limited to, a square structure. For example, the adjacent two side walls of the four side walls of the main body section 1 can be arranged perpendicular to each other. The main body section 1 has a channel 102 for the flow of molten solder. The molten solder can be flexibly selected according to the actual selective wave soldering requirements. For example, the molten solder is molten tin.

[0039] The nozzle has an upward-opening ejection chamber at its tip end. One side of the ejection chamber is a working area 201 located at the top of the biasing part 2, and the other side is a return area 101 located at the top of the main body section 1. At least one side of the return area 101 is provided with a notch 103, and the height of the top end face of the working area 201 is higher than the bottom height of the notch 103.

[0040] Channel 102 is connected to work area 201, supplying molten solder to work area 201;

[0041] like Figure 5 and 6As shown, the molten solder sprayed from above the working area 201 is used to contact the welding area 601a of the workpiece 6 for welding operation; the workpiece 6 can be a non-shaped PCB board, which has a horizontal part 601 and a vertical part 602 connected below the horizontal part 601. The welding area 601a is located on the lower surface of the horizontal part 601, and a shielding surface 602a protrudes from the vertical part 602. The shielding surface 602a is located directly below the welding area 601a, that is, the space between the shielding surface 602a and the horizontal part 601 constitutes a narrow space, which can also be called a blind zone 603.

[0042] The working area 201 and the reflow area 101 are connected to each other, so that molten solder flows from the working area 201 to the reflow area 101 and overflows outward through the notch 103.

[0043] This nozzle, applicable to blind zone welding, features a biasing section 2 on its main body 1. This biasing section 2 allows it to enter the blind zone 603, and molten solder is ejected from the working area 201 on the biasing section 2 to weld the welding area 601a above the blind zone 603. This overcomes the interference of the blind zone 603 structure on the welding process, enabling selective wave soldering in the blind zone 603. Furthermore, the notch 103 in the reflow zone 101 is staggered from the working area 201, allowing the molten solder ejected from the working area 201 to overflow through the notch 103 in the reflow zone 101, ensuring smooth reflow. The molten solder will not fall onto the shielding surface 602a of the blind zone 603, thus preventing the workpiece 6 from being contaminated. The molten solder overflowing from the notch 103 eventually falls back into the molten solder container (such as a solder pot). Here, compared to the traditional method where the nozzle sprays a wave peak from the center upwards and falls back into the solder pot from its periphery, the molten solder in this embodiment can only flow out from the notch 103. Therefore, during the flow process, the chance of the molten solder coming into contact with oxygen is greatly reduced. The reduced contact area results in less solder dross, thereby extending the nozzle cleaning cycle and saving costs.

[0044] In some examples, such as Figure 1 and 2 As shown, a downward-extending guide groove 104 is provided on the outer wall of the main body section 1 on the side where the notch 103 is located. The upper end of the guide groove 104 extends to the notch 103 and communicates with the notch 103, so that the molten solder flowing out of the notch 103 is restricted to flow downward along the guide groove 104 into the solder pot, further reducing the contact opportunity between the molten solder and oxygen, and reducing the generation of solder dross; it also avoids the molten solder from adhering to parts other than the guide groove 104 on the outer wall of the main body section 1 during the downward flow process.

[0045] When a notch 103 is opened on one side of the return zone 101, a guide channel 104 is opened on one side of the main body section 1. When a notch 103 is opened on both sides of the return zone 101, a guide channel 104 is opened on both sides of the main body section 1. This embodiment does not limit this. For example, the specific structure of the guide channel 104 opened on both sides of the main body section 1 can be as follows: the direction from the working area 201 to the return zone 101 is the first direction a1. The return zone 101 has notches 103 on both sides in the second direction b1. The second direction b1 is perpendicular to the first direction a1. The outer walls of both sides of the main body section 1 in the second direction b1 have guide channels 104. The upper end of the guide channel 104 extends to the notch 103 on its side and is connected to the notch 103 on its side.

[0046] The center line c1 of the reflow zone 101 extends vertically. The first direction a1, the second direction b1 and the center line c1 are perpendicular to each other. The bottom of the guide groove 104 gradually slopes away from the center line c1 of the reflow zone 101 from top to bottom. This means that the distance between the guide grooves 104 on both sides gradually increases from top to bottom, forming a figure-eight distribution. In this way, the molten solder can always be effectively guided during the downward flow of the molten solder.

[0047] In some examples, such as Figure 3 and 4 As shown, the bottom end of channel 102 has an inlet 102a for introducing molten solder into channel 102, and the top end of the side wall of channel 102 has a lateral hole 102b. Channel 102 is connected to the bottom end of working area 201 through lateral hole 102b. The bottom of working area 201 is a second bottom wall surface 201a, and the bottom of recirculation area 101 is a first bottom wall surface 101a. The height of the second bottom wall surface 201a is lower than the height of the first bottom wall surface 101a. This allows the molten solder supplied by channel 102 to enter working area 201 first and then flow to recirculation area 101, which is conducive to forming a virtuous cycle recirculation path. The virtuous cycle of molten solder is beneficial to improving the welding effect. In addition, when molten solder enters the ejection chamber, it is ejected from working area 201 to perform welding. Since the volume of working area 201 is smaller than the volume of the overall ejection chamber, it is beneficial to eject the ejection peak in working area 201.

[0048] In some examples, such as Figure 1 and 4As shown, a weir 4 is provided in the ejection chamber on the side where the notch 103 is located. The weir 4 can extend into the working area 201. That is, the two ends of the weir 4 can be connected to the opposite side walls of the ejection chamber in the first direction a1. The height of the top end face of the weir 4 is higher than the height of the first bottom wall surface 101a, and the top end face of the weir 4 defines the bottom of the notch 103, so that the molten solder can be pre-accumulated in the reflow area 101 and then overflow through the notch 103, so that the molten solder can flow stably at the ejection chamber.

[0049] In some examples, such as Figure 1 and 4 As shown, the end of the second bottom wall surface 201a away from the reflow area 101 has a guide surface 201b. The guide surface 201b gradually slopes from top to bottom towards the center line c1 of the reflow area 101. The end of the guide surface 201b away from the reflow area 101 is connected to the side wall of the working area 201 away from the reflow area 101 through the third bottom wall surface 201c. The height of the third bottom wall surface 201c is higher than the height of the second bottom wall surface 201a, but lower than the height of the first bottom wall surface 101a. The guide surface 201b is arranged opposite to the side hole 102b. When the molten solder in the channel 102 flows into the working area 201 from the side hole 102b, it will collide with the guide surface 201b. The guide surface 201b will guide the molten solder to flow upward and can also increase the strength of the bottom of the working area 201 at the corner.

[0050] In some examples, such as Figure 5 and 6 As shown, it also includes a mounting base 5, which is specifically fixedly installed at the solder pot containing molten solder. The mounting base 5 has a plug section 501, and the outer peripheral wall of the plug section 501 is provided with a positioning boss 501a and has a connecting hole 501b inside.

[0051] The bottom end of the main body segment 1 has a root 3, which can be integrally formed with the main body segment 1. The cross-sectional area of ​​the nozzle at the root 3 is greater than the cross-sectional area of ​​the main body segment 1, resulting in a structure where the main body segment 1 is thin and the root 3 is thick. The root 3 has a mounting hole 301 that matches the insertion segment 501. The mounting hole 301 can be, but is not less than, a round hole. At least one positioning groove 301a that matches the positioning boss 501a is opened on the inner peripheral wall of the mounting hole 301.

[0052] The plug section 501 is inserted into the mounting hole 301, and the positioning boss 501a is located in the positioning groove 301a. The cross-section of both the positioning boss 501a and the positioning groove 301a can be, but is not limited to, arc shape. The connecting hole 501b is connected to the inlet 102a of the channel 102. Through the cooperation of the positioning boss 501a and the positioning groove 301a, the circumferential positioning between the plug section 501 and the connecting hole 501b can be achieved, so that the nozzle can be accurately positioned and installed.

[0053] The mounting hole 301 has multiple positioning grooves 301a distributed circumferentially. When the positioning boss 501a is matched with the positioning grooves 301a at different circumferential positions, the nozzle will present different circumferential mounting positions, thereby realizing that the nozzle has multiple mounting positions.

[0054] In some examples, a selective wave soldering apparatus includes the aforementioned nozzle suitable for blind zone soldering. The selective wave soldering apparatus also has a molten solder container (e.g., a solder pot, which can heat and keep the molten solder inside) for containing molten solder. The mounting base 5 is fixed on the solder pot. The molten solder in the solder pot can be pumped into the connecting hole 501b of the mounting base 5 by a delivery pump, and then reaches the channel 102 of the nozzle through the connecting hole 501b. The delivery pump can be, but is not limited to, an electromagnetic pump, an impeller pump, etc.

[0055] The working principle of the above-mentioned nozzle applicable to blind zone welding is as follows:

[0056] During welding, the nozzle biasing part 2 is located within the blind zone 603 of the workpiece 6, so that the working area 201 is aligned with the welding area 601a above the inside of the blind zone 603.

[0057] The electromagnetic pump is started to pump the molten solder in the tin pot into the connecting hole 501b, and then through the connecting hole 501b to the channel 102. Subsequently, the molten solder in the channel 102 enters the working area 201 from the side hole 102b, and then sprays upward from the working area 201 to form a wave peak, so that the molten solder contacts the welding area 601a above the blind area 603 to perform the welding operation. Then, the molten solder in the working area 201 flows to the return area 101 and overflows outward from the gap 103 in the return area 101. The molten solder overflowing from the gap 103 will flow directly downward along the guide groove 104 into the tin pot, forming a virtuous cycle return path. The virtuous cycle of the molten solder is beneficial to improving the welding effect.

[0058] In this way, selective wave soldering of the blind zone 603 is achieved, and the shielding surface 602a within the blind zone 603 is not contaminated. Furthermore, the contact with oxygen during the reflow of molten solder is reduced, thereby reducing the generation of solder dross, extending the cleaning cycle of solder dross in the electromagnetic pump, and thus saving on operating costs.

[0059] The above description, based on the preferred embodiments of the present invention, provides inspiration. Those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification but must be determined according to the claims.

Claims

1. A nozzle suitable for blind zone welding, characterized in that: The nozzle has a main body section (1) and an offset portion (2) protruding from one side wall of the top of the main body section (1), and the main body section (1) has a channel (102) for the flow of molten solder inside; The nozzle has an upward-opening ejection chamber at its top end. One side of the ejection chamber is a working area (201) located at the top of the biasing part (2), and the other side is a return area (101) located at the top of the main body section (1). At least one side of the return area (101) is provided with a notch (103). The channel (102) is connected to the working area (201) and supplies molten solder to the working area (201); The molten solder sprayed above the work area (201) is used to contact the welding area (601a) of the workpiece (6) to perform the welding operation; The working area (201) and the reflow area (101) are connected to each other, so that molten solder flows from the working area (201) to the reflow area (101) and overflows outward through the notch (103).

2. The nozzle applicable to blind zone welding according to claim 1, characterized in that: The outer wall of the main body section (1) is provided with a downwardly extending guide groove (104) on the side where the notch (103) is located. The upper end of the guide groove (104) extends to the notch (103) and communicates with the notch (103).

3. The nozzle applicable to blind zone welding according to claim 2, characterized in that: The direction from the working area (201) to the return area (101) is the first direction (a1). The return area (101) has notches (103) on both sides in the second direction (b1). The second direction (b1) is perpendicular to the first direction (a1). The main body section (1) has guide grooves (104) on both outer walls in the second direction (b1). The upper end of the guide groove (104) extends to the notch (103) on its side and is connected to the notch (103) on its side.

4. The nozzle applicable to blind zone welding according to claim 2, characterized in that: The bottom of the guide channel (104) gradually slopes from top to bottom toward the center line (c1) away from the return zone (101).

5. The nozzle applicable to blind zone welding according to claim 1, characterized in that: The bottom of the working area (201) is a second bottom wall surface (201a), and the bottom of the reflux area (101) is a first bottom wall surface (101a). The height of the second bottom wall surface (201a) is lower than the height of the first bottom wall surface (101a).

6. The nozzle applicable to blind zone welding according to claim 5, characterized in that: A dam (4) is provided in the ejection chamber on the side where the gap (103) is located. The height of the top end face of the dam (4) is higher than the height of the first bottom wall (101a), and the top end face of the dam (4) defines the bottom of the gap (103).

7. The nozzle applicable to blind zone welding according to claim 5, characterized in that: The second bottom wall surface (201a) has a guide surface (201b) at the end away from the reflux area (101). The guide surface (201b) gradually slopes from top to bottom toward the center line (c1) of the reflux area (101). The end of the guide surface (201b) away from the reflux area (101) is connected to the side wall of the working area (201) away from the reflux area (101) through the third bottom wall surface (201c). The height of the third bottom wall surface (201c) is higher than the height of the second bottom wall surface (201a), but lower than the height of the first bottom wall surface (101a).

8. The nozzle applicable to blind zone welding according to claim 7, characterized in that: The bottom end of the channel (102) has an inlet (102a) for introducing molten solder into the channel (102), and the top end of the sidewall of the channel (102) has a lateral hole (102b). The channel (102) is connected to the bottom end of the working area (201) through the lateral hole (102b), and the lateral hole (102b) is arranged opposite to the guide surface (201b).

9. The nozzle applicable to blind zone welding according to claim 8, characterized in that: It also includes a mounting base (5), which has a plug section (501) on its outer peripheral wall and a positioning boss (501a) and a connecting hole (501b) inside. The bottom end of the main body section (1) has a root (3), and the root (3) has a mounting hole (301) that matches the insertion section (501). At least one positioning groove (301a) that matches the positioning boss (501a) is opened on the inner peripheral wall of the mounting hole (301). The plug segment (501) is inserted into the mounting hole (301), and the positioning boss (501a) is located in the positioning groove (301a). The connecting hole (501b) is connected to the entrance (102a) of the channel (102).

10. A selective wave soldering apparatus, characterized in that: Includes a nozzle applicable to blind zone welding as described in any one of claims 1-9.

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