Welding jig

Abstract

The invention relates to the technical field of welding tools, in particular to a welding jig which comprises a positioning mechanism, a limiting mechanism and a fixing mechanism. The positioning mechanism comprises a rotating assembly and a telescopic assembly; the rotating assembly is connected with the circuit board; the telescopic assembly is connected with the rotating assembly; the limiting mechanism is connected with the rotating assembly; the fixing mechanism is connected with the telescopic assembly; according to the invention, after the annular sleeve is aligned with the copper hole in the circuit board, the electronic element pin is fixed by clamping towards the center of the copper hole, and the fixing mechanism and the annular sleeve at the pin with the welding quality reaching the standard are separated from other mechanisms by using high temperature generated in the welding process; therefore, the jig cost is reduced, and the pins needing repair welding can be quickly checked. Therefore, the problems that the soldering quality is reduced and a large amount of time needs to be consumed for inspection and repair welding in the later period because the pins deviate from the center of the copper hole of the circuit board and soldering tin is not uniformly distributed during wave soldering are solved.

Description

Technical Field

[0001] The invention relates to the technical field of welding tooling, and in particular to a welding jig. Background Art

[0002] A welding jig is a tool used to maintain the position and shape of the workpiece during welding, and to clamp the workpiece to ensure the stability and accuracy of the workpiece during welding. The use of a welding jig helps to ensure accurate positioning during welding, improve welding accuracy and quality, reduce welding defects, and also simplify the welding process and improve production efficiency.

[0003] At present, welding jigs have been used in welding in various fields, especially in the electronics industry. When welding electronic components, welding jigs are usually needed to ensure welding positioning accuracy and stability during welding. When welding electronic components with pins, the pins need to be inserted into the copper holes of the circuit board, and then the pins inserted into the copper holes of the circuit board are welded to the circuit board through wave soldering. For electronic components with light weight and a small number of pins, they usually shake after being inserted into the copper holes. At this time, after wave soldering, the electronic components will be deflected, thereby reducing the welding quality and aesthetics. The prior art has proposed a good solution to this problem, such as a circuit board pin wave soldering positioning jig and circuit board pin with patent publication number CN114245610B; a wave soldering positioning jig is designed, which passes the pins through the positioning sleeve and the copper hole of the circuit board, and then shrinks the positioning sleeve to fix the plug-in pins to prevent the pins from moving during welding and causing the electronic components to shift.

[0004] Although the existing technology has solved the problem that when electronic components with light weight and a small number of pins are welded, the electronic components are offset due to the movement of the pins, thereby resulting in a decrease in welding quality, the following problems still exist: when wave soldering is performed on high-precision circuit boards in medical devices, it is necessary to ensure that the electronic components cannot be offset and to ensure the welding quality and stability, otherwise any treatment errors caused by minor faults will result in immeasurable losses. Since the electronic components are small and are fixed using steel ropes or the like, after the fixture is fully tightened, the pins will be offset in a certain direction in the copper holes or the pins will be bent. Since the pins deviate from the center of the circle, wave soldering at this time will result in uneven solder distribution, thereby affecting the strength and stability of the welding, resulting in cold solder joints and the like, resulting in a decrease in welding quality, and requiring a lot of time to be spent on inspection and re-welding later.

[0005] In view of the above situation, in order to overcome the above technical problems, the present invention provides a welding jig. Summary of the invention

[0006] The present invention provides a welding jig, which solves the problem that during the pin welding process, the pin deviates from the center of the copper hole of a circuit board, resulting in uneven distribution of solder liquid during wave soldering, which leads to reduced welding quality and requires a lot of time for inspection and re-welding at a later stage. After the annular sleeve is aligned with the copper hole on the circuit board, the pin of the electronic component is fixed by clamping it to the center of the copper hole, and the high temperature generated during the welding process is used to separate the fixing mechanism and the annular sleeve at the pin that meets the welding quality standard from the other mechanisms, thereby reducing the cost of the jig and quickly checking the pin that needs re-welding.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A welding jig; comprising a positioning mechanism, a limiting mechanism and a fixing mechanism; the positioning mechanism comprises a rotating assembly and a telescopic assembly; the rotating assembly is connected to a circuit board; the telescopic assembly is connected to the rotating assembly; the limiting mechanism is connected to the rotating assembly; the fixing mechanism is connected to the telescopic assembly; when using the welding jig, the rotating assembly is connected to the circuit board and the rotating assembly is rotated, the rotating assembly drives the telescopic assembly to rotate until the center line of the telescopic assembly intersects with the center of a copper hole on the circuit board, the telescopic assembly is stretched to a position where it coincides with the copper hole, the limiting mechanism is pressed down so that the limiting mechanism limits the rotating assembly, the pins of the electronic components are inserted into the fixing mechanism, the fixing mechanism is squeezed by the pins to shrink and clamp the pins of the electronic components to the center of the copper hole.

[0009] Preferably, the rotating assembly includes a positioning shaft and a rotating rod; the positioning shaft is connected to the circuit board when the welding jig is in use; multiple rotating rods are connected to the positioning shaft; the telescopic assembly includes a telescopic sleeve, an annular sleeve and a positioning pressure rope; the telescopic sleeve is connected to the rotating rod; the annular sleeve is connected to the telescopic sleeve; and the positioning pressure rope is connected to the annular sleeve.

[0010] In the above scheme, after the positioning shaft is fixed, the rotating action of the rotating rod and the sliding action of the telescopic sleeve can help the annular sleeve to move in any direction, so that the annular sleeve can be docked with the copper hole position on the circuit board, and the welding fixture can adapt to circuit boards of various specifications and different opening positions, thereby improving practicality.

[0011] Preferably, an expansion air cavity is opened in the annular sleeve, and three shrinkage holes are opened in a circular array on the inner wall of the annular sleeve; the three positioning pressure ropes are installed in the shrinkage holes, and the positioning pressure rope is a Y-shaped structure. The upper end of the Y-shaped structure can be deformed when under pressure, and the positioning pressure rope is made of high thermal conductivity material.

[0012] In the above scheme, the circuit board drives the welding jig into the wave soldering furnace body. During wave soldering, the high-temperature solder will come into contact with the copper holes, positioning pressure ropes and pins of electronic components. Since the positioning pressure rope is made of high thermal conductivity material, the temperature can be quickly introduced into the expansion air cavity, causing the air in the expansion air cavity to expand at high temperature, thereby separating the annular sleeve and the telescopic sliding sleeve and removing them after welding is completed, so that the welding jig except the annular sleeve and the positioning pressure rope structure can be used multiple times, saving costs.

[0013] Preferably, the telescopic sleeve is made of platinum-cured silicone rubber, and a clamping block is provided at the top of the telescopic sleeve; and a clamping groove is provided at the opening position of the expansion air cavity.

[0014] In the above scheme, the annular sleeve can be clamped on the telescopic sleeve through the clamping block when using the fixture, and the clamping can be performed according to the actual required number, thereby saving costs, and ensuring that the annular sleeve and the telescopic sleeve remain fixed under normal conditions, avoiding the annular sleeve from shifting and causing the pins of the electronic components to shift; because the solder liquid temperature is maintained at around 240 degrees during wave soldering, and platinum-cured silicone rubber can still maintain a certain elasticity at 300 degrees, and is not easy to undergo plastic deformation, and its cost is lower than that of fluororubber; the use of platinum-cured silicone rubber can cause the gas in the expansion cavity to expand and then cause the clamping block to deform, thereby pushing the clamping block out of the clamping groove under the action of the gas; at this time, the welding effect can be judged by whether the clamping block is pushed out, and in the subsequent inspection and re-welding process, the copper holes at the clamping blocks that have not been pushed out can be quickly locked to check whether they need re-welding; avoiding a large number of checks on whether re-welding is needed, saving time, and improving welding efficiency.

[0015] Preferably, a fitting surface that fits with the inner wall of the expansion air cavity is provided at the top of the clamping block, and a balancing air hole is provided at the rear flat end of the clamping block.

[0016] In the above scheme, a fitting surface is provided to ensure the gas sealing of the expanded air cavity after the clamping block is inserted into the annular sleeve, so that the gas is heated up and expanded and exerts pressure on the surface of the clamping block, causing the clamping block to deform and pop out; when the circuit board enters the cooling area after welding is completed, air is allowed to flow in through the balancing air holes to avoid the reduction of air pressure inside the expanded air cavity after cooling, which causes the clamping block to be re-sucked into the clamping groove, affecting the subsequent inspection and re-welding work.

[0017] Preferably, a telescopic slide sleeve is provided with a telescopic slide groove; a wave tooth 1 is provided on the telescopic slide groove; and wave teeth 2 meshing with the wave tooth 1 are provided on the edges of both sides of the rotating rod.

[0018] In the above scheme, since the telescopic sleeve is made of silicone rubber as a whole, the wavy tooth 1 can be slightly deformed during the relative sliding process with the wavy tooth 2. After the telescopic sleeve slides out until the annular sleeve and the copper hole on the circuit board coincide with each other, the wavy tooth 1 on the telescopic slide groove and the wavy tooth 2 on the rotating rod can mesh with each other, so that the annular sleeve will not move without a large external force, thereby improving the stability of the annular sleeve and the positioning pressure rope after fixing the pins of the electronic components.

[0019] Preferably, the limiting mechanism includes a limiting rotation groove, a limiting rotation block, a limiting clamping block and a clamping block groove; the limiting rotation groove is arranged at the upper part of the positioning shaft; the limiting rotation block is installed in the limiting rotation groove; the limiting clamping block is connected to the limiting rotation block, and the limiting clamping block is an inverted F-shaped structure; the clamping block groove is arranged at the lower part of the positioning shaft, and the upper inner circle of the clamping block groove is provided with a shrinkage fillet; a through arc groove is arranged on the rotating rod.

[0020] In the above scheme, by setting a limit turn block, when each rotating rod is rotated to any position, the limit turn block can be rotated to a position that can fix all the rotating rods; after pressing down the limit clamp block, the limit clamp block can enter the clamp block groove through the through arc groove to clamp and limit multiple rotating rods, so that the rotating rods cannot rotate, thereby cooperating with the wavy teeth on the telescopic sliding sleeve to fix the annular sleeve after positioning is completed, ensuring that the pins of the electronic components will not be eccentric with the copper holes on the circuit board after being inserted into the annular sleeve.

[0021] Preferably, the fixing mechanism includes a fixing claw and a shielding surface; the fixing claw is connected to the positioning pressure rope, and the fixing claw is an arc-shaped structure; the shielding surface is connected to the upper end of the annular sleeve, and its cross-section is an eight-shaped structure, the inner diameter of the shielding surface is larger than the outer diameter of the fixing claw, and the upper end surface of the fixing claw is higher than the highest point of the lower end surface of the shielding surface.

[0022] In the above scheme, the fixing claws are connected to the positioning pressure rope, so that the three fixing claws can gather toward the center of the circle under the action of the positioning pressure rope, so that the fixing claws clamp the pins of the electronic components and fix the pins of the electronic components at the center of the circle, so that the solder liquid can be evenly distributed when entering between the copper holes and the pins of the circuit board, and form full solder joints; the contact area between the fixing claws and the pins can be increased, so that the pins are more stable after being fixed and will not be affected by the flow of solder liquid, and the pin deflection is avoided to reduce the welding quality; the side wall of the annular sleeve and the shielding surface can also block the solder liquid, and avoid the solder liquid overflowing due to the high waves formed by the solder liquid during wave soldering, forming a continuous soldering on the upper side of the circuit board. Through the shielding effect of the shielding surface, the wave height of the wave soldering can be appropriately increased, so that the solder joint is fuller, and the lower surface area of ​​the shielding surface is large and in an eight-shaped shape, which can fit the wave shape formed by the solder liquid, so that the solder liquid can be better adhered to it, thereby improving the stability of welding.

[0023] Preferably, the fixing claw is provided with a compression fillet at the upper end, a drainage fillet at the lower end, and a plurality of protrusions on the side wall.

[0024] In the above scheme, when inserting the electronic component, the pin of the electronic component is squeezed by the compression fillet, which can make the pin easier to enter between the three fixing claws and avoid bending of the pin. Through the cooperation of the drainage fillet and the bump, when the solder liquid passes through the drainage fillet and reaches the gap between the bump and the pin, the solder liquid is retained by the bump, thereby making the solder joint fuller and improving the welding quality.

[0025] Preferably, the annular sleeve is made of an insulating material that can withstand high temperatures above 240 degrees; the lower surface of the shielding surface and the side walls and lower surface of the annular sleeve are all provided with attachment surfaces.

[0026] In the above scheme, since the annular sleeve is arranged above the circuit board, after the solder liquid enters the copper hole, the contact area between the solder liquid and the annular sleeve can be increased by setting the adhesion surface, making it easier for the solder liquid to adhere to the lower surface and side wall of the annular sleeve, thereby better wrapping the pins of the electronic components to form full solder joints.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. Compared with the existing wave soldering jig, the present invention evenly distributes the fixing claws and the positioning pressure ropes on the circumference of the annular sleeve, and applies a pressing force to the pins of the electronic components at the center of the circle, so that the pins of the electronic components are fixed at the center of the circle, so that the solder liquid entering the copper hole is evenly distributed, and the formed solder joints are full to avoid the phenomenon of cold soldering; and the pressing force is more stable by increasing the contact area between the fixing claws and the pins, and convex points are provided on the inner surface of the fixing claws, on the one hand, the friction between the pins is increased to ensure that the pins will not shake, thereby improving the welding quality; on the other hand, when the solder liquid reaches the gap between the convex points and the pins, the solder liquid is retained by the convex points, so that the solder joints are fuller and the welding quality is improved.

[0029] 2. The present invention sets a telescopic component and a rotating component so that the annular sleeve can move in any direction to adapt to circuit boards of various specifications, and designs the annular sleeve and the telescopic sleeve as a detachable structure. The annular sleeve can be loaded and unloaded according to the number of pins required to be welded, thereby reducing costs and improving practicality. When welding, the welding liquid fully contacts the positioning pressure rope to expand the gas in the expansion air cavity, so that the clamping block automatically pops out of the clamping groove, so that the telescopic sleeve can be directly pulled out of the annular sleeve later. On the one hand, the structure except the structure in the annular sleeve and the fixing mechanism can be reused, thereby reducing costs. On the other hand, the popping out of the clamping block can be used to quickly determine whether subsequent re-welding is required, and re-weld the pins that have not popped out, thereby reducing the time cost of subsequent inspections and improving welding quality.

[0030] 3. The present invention sets a shielding surface on the upper surface of the annular sleeve and limits the solder liquid through the side wall of the annular sleeve, thereby preventing the solder liquid from overflowing above the copper hole due to excessively high waves during wave soldering, causing continuous soldering on the surface of the circuit board; the shielding effect of the shielding surface can appropriately increase the wave of wave soldering, and the eight-shaped structure of the lower end surface of the shielding surface can make the solder liquid entering the copper hole and the attachment surface on the lower end surface of the shielding surface more closely fit, so that the solder liquid is easier to adhere between the copper hole and the pin, and the formed solder joints are fuller, so that the welding stability is improved, thereby improving the welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the connection between the present invention, the circuit board and the electronic components;

[0033] Figure 2 It is a schematic diagram of the overall structure of the present invention;

[0034] Figure 3 It is a schematic diagram of the connection structure of the rotating assembly and the telescopic assembly of the present invention;

[0035] Figure 4 It is a schematic diagram of the internal structure of the expansion air cavity of the present invention;

[0036] Figure 5 for Figure 4 A magnified view of the structure at center;

[0037] Figure 6 It is a schematic diagram of the rotating rod structure of the present invention;

[0038] Figure 7 It is a cross-sectional view of the limiting mechanism of the present invention;

[0039] Figure 8 It is a schematic diagram of the fixed claw structure of the present invention;

[0040] Fig. 9 It is a cross-sectional view of the internal structure of the annular sleeve of the present invention;

[0041] Fig.10 It is a schematic diagram of the attachment surface structure of the present invention;

[0042] In the figure: a, circuit board; a1, copper hole; b, electronic component; b1, pin; 1, positioning mechanism; 11, rotating assembly; 111, positioning shaft; 112, rotating rod; 1121, wave tooth 2; 1122, through arc groove; 12, telescopic assembly; 121, telescopic sleeve; 1211, clamping block; 1212, fitting surface; 1213, balancing air hole; 1214, telescopic slide; 1215, wave tooth 1; 1 22. Annular sleeve; 1221. Expansion air cavity; 1222. Contraction hole; 1223. Snap-in groove; 123. Positioning pressure rope; 2. Limiting mechanism; 21. Limiting rotating groove; 22. Limiting rotating block; 23. Limiting clamping block; 24. Clamping block groove; 241. Contraction fillet; 3. Fixing mechanism; 31. Fixing claw; 311. Compression fillet; 312. Drainage fillet; 313. Bump; 32. Shielding surface; 321. Attachment surface. DETAILED DESCRIPTION

[0043] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0044] See also Figures 1 to 10 The present invention provides a welding jig, and the technical solution is as follows:

[0045] As a specific embodiment of the present invention, refer to Figure 1 and Figure 2 A welding jig; comprising a positioning mechanism 1, a limiting mechanism 2 and a fixing mechanism 3; the positioning mechanism 1 comprises a rotating assembly 11 and a telescopic assembly 12; the rotating assembly 11 is connected to a circuit board a; the telescopic assembly 12 is connected to the rotating assembly 11; the limiting mechanism 2 is connected to the rotating assembly 11; the fixing mechanism 3 is connected to the telescopic assembly 12; when using the welding jig, the rotating assembly 11 is connected to the circuit board a, the rotating assembly 11 is rotated, and the rotating assembly 11 drives the telescopic assembly 12 to rotate to the telescopic assembly 1 2 intersects with the center of the copper hole a1 on the circuit board a, stretch the telescopic component 12 to the position where it coincides with the copper hole a1, press the limiting mechanism 2 downward to limit the rotating component 11, ensure that the telescopic component 12 cannot move after coinciding with the copper hole a1, insert the pin b1 of the electronic component b into the fixing mechanism 3, the fixing mechanism 3 is squeezed by the pin b1 to contract and clamp the pin b1 of the electronic component b toward the center of the copper hole a1, so that the pin b1 of the electronic component b is fixed at the center of the copper hole a1, so that the solder liquid is evenly distributed when entering the copper hole.

[0046] As a specific embodiment of the present invention, refer to Figure 2 , Figure 3 , Figure 4 and Figure 5The rotating assembly 11 includes a positioning shaft 111 and a rotating rod 112; when the welding jig is in use, the positioning shaft 111 is connected to the circuit board a; a plurality of rotating rods 112 are connected to the positioning shaft 111; the telescopic assembly 12 includes a telescopic sleeve 121, an annular sleeve 122 and a positioning pressure rope 123; the telescopic sleeve 121 is connected to the rotating rod 112; the annular sleeve 122 is connected to the telescopic sleeve 121; the positioning pressure rope 123 is connected to the annular sleeve 122. After the positioning shaft 111 is fixed, the annular sleeve 122 can be helped to move in any direction through the rotating action of the rotating rod 112 and the sliding action of the telescopic sleeve 121, so that the annular sleeve 122 can be docked to the copper hole a1 position on the circuit board a, and the welding jig can adapt to circuit boards a of various specifications and different opening positions, thereby improving practicality.

[0047] As a specific embodiment of the present invention, refer to Figure 4; An expansion air cavity 1221 is opened in the annular sleeve 122, and three shrinkage holes 1222 are opened in a circular array on the inner wall of the annular sleeve 122; the three positioning pressure ropes 123 are installed in the shrinkage holes 1222, and the positioning pressure rope 123 is a Y-shaped structure. The upper end of the Y-shaped structure can be deformed when under pressure. The Y-shaped structure of the positioning pressure rope 123 and the inner wall of the expansion air cavity 1221 are squeezed against each other, and can provide a clamping force toward the center of the circle, so that the pin can be subjected to uniform compression force when inserted; the positioning pressure rope 123 is made of high thermal conductivity material. When the circuit board a drives the welding fixture into the wave soldering furnace, the high-temperature solder will contact the copper hole a1, the positioning pressure rope 123 and the pin b1 of the electronic component b during wave soldering. Since the positioning pressure rope 123 is made of high thermal conductivity material, the temperature can be quickly introduced into the expansion cavity 1221, so that the air in the expansion cavity 1221 expands at high temperature, so that the annular sleeve 122 and the telescopic sleeve 121 are separated and disassembled after the welding is completed, so that the welding fixture except the annular sleeve 122 and the positioning pressure rope 123 can be used multiple times, saving costs. The telescopic sleeve 121 is made of platinum-cured silicone rubber, and a clamping block 1211 is provided at the top of the telescopic sleeve 121; a clamping groove 1223 is provided at the opening of the expansion cavity 1221.By means of the clamping block 1211, the annular sleeve 122 can be clamped onto the telescopic sleeve 121 when the jig is used, and the clamping can be performed according to the actual number required, thereby saving costs, and ensuring that the annular sleeve 122 and the telescopic sleeve 121 remain fixed under normal conditions, so as to prevent the annular sleeve 122 from shifting and causing the pin b1 of the electronic component b to shift; during wave soldering, the solder liquid temperature is maintained at about 240 degrees, and the platinum-cured silicone rubber can still maintain a certain elasticity at 300 degrees, and is not prone to plastic deformation, and its cost is lower than that of fluororubber; the use of platinum-cured silicone rubber can cause the gas in the expansion air cavity 1221 to expand and cause the clamping block 1211 to deform, so that the clamping block 1211 is pushed out of the clamping groove 1223 under the action of the gas, and at this time the expanded air will reach the middle position of the two clamping blocks 1211, and generate thrust on the telescopic sleeve 121, so that the telescopic sleeve 121 is clamped onto the side wall of the expansion air cavity 1221; and because The expansion coefficient of air is about 0.00367, that is, after the solder liquid is in full contact with the positioning pressure rope 123, when the air temperature in the expansion air cavity 1221 rises to above 200 degrees, the air in the expansion air cavity 1221 can expand to about 1.7 times of the original volume. Before use, it is necessary to test the thickness of the clamping block 1211 to ensure that under the air pressure, the deformation of the clamping block 1211 can be ejected from the clamping groove 1223, and when the air temperature is below 200 degrees (that is, the air volume expands to less than 1.7 times), the pressure on the clamping block 1211 cannot cause it to deform. At this time, the welding effect can be judged by whether the clamping block 1211 is pushed out. In the subsequent inspection and repair welding process, the copper hole a1 under the annular sleeve 122 where the clamping block 1211 is not pushed out can be quickly locked to check whether it needs repair welding; thereby avoiding a large number of checks on whether repair welding is needed, saving time, and improving welding efficiency. The top of the clamping block 1211 is provided with a fitting surface 1212 that fits with the inner wall of the expansion air cavity 1221 , and the tail flat end of the clamping block 1211 is provided with a balancing air hole 1213 . By setting the fitting surface 1212, it is ensured that the gas sealing in the expanded air cavity 1221 after the clamping block 1211 is inserted into the annular sleeve 122 is ensured, so that the gas is heated and expanded and exerts pressure on the surface of the clamping block 1211, so that the clamping block 1211 is deformed and popped out; after the circuit board a enters the cooling area after welding is completed, air is allowed to flow in through the balancing air hole 1213 to avoid the internal air pressure of the expanded air cavity 1221 being reduced after cooling and the air volume shrinking, causing the clamping block 1211 to be re-sucked into the clamping groove 1223, affecting the subsequent inspection and soldering work; at the same time, after the clamping block 1211 is deformed and popped out, the clamping block 1211 will be stuck with the side wall of the expanded air cavity 1221, and the expanded air is discharged under the action of the balancing air hole 1213, so that the annular sleeve 122 and the telescopic sleeve 121 will not be completely separated, and when the telescopic sleeve 121 is separated, the solder liquid has not yet solidified, causing the position of the annular sleeve 122 to deviate, resulting in the position of the pin b1 to shift.

[0048] As a specific embodiment of the present invention, refer to Figure 4 and Figure 5 A telescopic slide groove 1214 is provided inside the telescopic slide sleeve 121; a wave tooth 1 1215 is provided on the telescopic slide groove 1214; and wave teeth 2 1121 meshing with the wave teeth 1 1215 are provided on both sides of the rotating rod 112. Since the telescopic sleeve 121 is made of silicone rubber as a whole, the wave tooth 1215 can be slightly deformed during the relative sliding process with the wave tooth 1121. After the telescopic sleeve 121 slides out to the point where the annular sleeve 122 coincides with the copper hole a1 on the circuit board a, the wave tooth 1215 on the telescopic slide 1214 and the wave tooth 1121 on the rotating rod 112 can mesh with each other to prevent the annular sleeve 122 from moving without a large external force, thereby improving the stability of the annular sleeve 122 and the positioning pressure rope 123 after fixing the pin b1 of the electronic component b; and under the action of air pressure after the air expands, the impact of the telescopic sleeve 121 popping out is reduced, and through the action of the wave tooth 1215 and the wave tooth 1121, the clamping block 1211 can only move one wave tooth pitch after it pops out, thereby avoiding the influence of the telescopic sleeve 121 on the position of the annular sleeve 122 after sliding.

[0049] As a specific embodiment of the present invention, refer to Figure 4 , Figure 5 , Figure 6 and Figure 7The limiting mechanism 2 includes a limiting rotation groove 21, a limiting rotation block 22, a limiting clamping block 23 and a clamping block groove 24; the limiting rotation groove 21 is arranged on the upper part of the positioning shaft 111; the limiting rotation block 22 is installed in the limiting rotation groove 21; the limiting clamping block 23 is connected to the limiting rotation block 22, and the limiting clamping block 23 is an inverted F-shaped structure, and the distance between the two horizontal parts of the F-shaped structure is slightly smaller than the total thickness of the multi-piece rotating rod 112, so as to ensure the clamping force and prevent the rotating rod 112 from rotating, and the structure at the horizontal position of the lower end of the inverted F structure is a deformable buckle structure, and the upper end is a hard structure. When disassembling, by pulling up the horizontal position of the upper end, The hard structure causes the structure at the lower end horizontal position of the deformation-stuck and clamped multiple rotating rods 112 to deform again and exit the clamping block groove 24; the clamping block groove 24 is arranged at the lower part of the positioning shaft 111, and the upper inner circle of the clamping block groove 24 is provided with a shrinkage fillet 241; the rotating rod 112 is provided with a through arc groove 1122, and the arc of the through arc groove 1122 is greater than 300 degrees, so as to ensure that there is an overlapping position between the multiple through arc grooves 1122 (because there is a gap between the copper holes a1 on the circuit board a, when each annular sleeve 122 is aligned with the copper hole a1, it is inevitable that there will be a certain degree of angle between each rotating rod 112). By setting the limit rotating block 22, when each rotating rod 112 is rotated to any position, the limit rotating block 22 can be rotated to a position that can fix all the rotating rods 112, that is, the overlapping position of the through arc groove 1122 on each rotating rod 112; after pressing down the limit clamping block 23, the limit clamping block 23 can pass through the through arc groove 1122, at this time, the lower structure of the limit clamping block 23 is squeezed with the shrinkage fillet 241, at this time, the lower part of the limit clamping block 23 is slightly deformed and enters into the clamping block groove 24, and the multiple rotating rods 112 are clamped and limited by the transverse structure of the upper and lower parts of the limit clamping block 23, so that the rotating rods 112 cannot rotate, thereby cooperating with the wavy teeth on the telescopic sliding sleeve 121, so that the annular sleeve 122 is fixed after positioning is completed, to ensure that the pin b1 of the electronic component b will not be eccentric with the copper hole a1 on the circuit board a after being inserted into the annular sleeve 122.

[0050] As a specific embodiment of the present invention, refer to Figure 8 , Fig. 9 and Fig.10The fixing mechanism 3 includes a fixing claw 31 and a shielding surface 32; the fixing claw 31 is connected to the positioning pressure rope 123, and the fixing claw 31 is an arc-shaped structure; the shielding surface 32 is connected to the upper end of the annular sleeve 122, and its cross section is an eight-shaped structure, the inner diameter of the shielding surface 32 is larger than the outer diameter of the fixing claw 31, and the upper end surface of the fixing claw 31 is higher than the highest point of the lower end surface of the shielding surface 32. The fixing claw 31 is connected to the positioning pressure rope 123, so that the three fixing claws 31 can be gathered to the center of the circle under the action of the positioning pressure rope 123, so that the fixing claw 31 clamps the pin b1 of the electronic component b and fixes the pin b1 of the electronic component b at the center of the circle, so that the solder liquid can be evenly distributed when entering between the copper hole a1 and the pin b1 of the circuit board a, and a full solder joint can be formed; the contact area between the fixing claw 31 and the pin b1 can be increased, so that the pin b1 is more stable after being fixed and will not be affected by the flow of solder liquid, avoiding the lead The deflection of foot b1 reduces the welding quality; the side wall of the annular sleeve 122 and the shielding surface 32 can also block the solder liquid to prevent the solder liquid from overflowing due to the high waves formed by the solder liquid during wave soldering, forming a continuous soldering on the upper side of the circuit board a. Through the shielding effect of the shielding surface 32, the wave height of the wave soldering can be appropriately increased, so that the solder point is fuller, and the lower surface area of ​​the shielding surface 32 is large and in an eight-shaped shape, which can fit the wave shape formed by the solder liquid, so that the solder liquid can adhere to it better, thereby improving the welding stability.

[0051] As a specific embodiment of the present invention, refer to Figure 8 , Fig. 9 and Fig.10 The upper end of the fixing claw 31 is provided with a compression fillet 311, the lower end is provided with a drainage fillet 312, and the side wall is provided with a plurality of protrusions 313. When inserting the electronic component b, the pin b1 of the electronic component b is squeezed by the compression fillet 311, so that the pin b1 can be more easily inserted between the three fixing claws 31, and the pin b1 is prevented from bending. The drainage fillet 312 and the protrusion 313 cooperate to make the solder liquid reach the gap between the protrusion 313 and the pin b1 after passing through the drainage fillet 312. The solder liquid is retained by the protrusion 313, so that the solder joint is fuller and the welding quality is improved. The annular sleeve 122 is made of an insulating material that can withstand high temperatures above 240 degrees; the lower surface of the shielding surface 32 and the side wall and lower surface of the annular sleeve 122 are provided with an attachment surface 321. Since the annular sleeve 122 is arranged above the circuit board a, after the solder liquid enters the copper hole a1, the contact area between the solder liquid and the annular sleeve 122 can be increased by setting the adhesion surface 321, making it easier for the solder liquid to adhere to the lower surface and side wall of the annular sleeve 122, thereby better wrapping the pin b1 of the electronic component b to form a full solder joint.

[0052] Working principle: When using a welding fixture, use silicone to adhere the positioning shaft 111 to the circuit board a, rotate the rotating component 11, and the rotating component 11 drives the telescopic component 12 to rotate to the center line of the telescopic component 12 (i.e. Figure 1 The midpoint line) intersects with the center of the copper hole a1 on the circuit board a. At this time, the telescopic component 12 is stretched until the annular sleeve 122 coincides with the copper hole a1; the limiting mechanism 2 is pressed down to clamp the rotating component 11 to limit the position, so that the annular sleeve 122 is fixed, and the pin b1 of the electronic component b is inserted between the fixing claws 31, so that the fixing claws 31 clamp the fixed pin b1.

[0053] Specifically, according to the number of pins b1 to be welded, the annular sleeve 122 is inserted into the telescopic sleeve 121, so that the clamping block 1211 enters the clamping groove 1223; when using the welding fixture, the positioning shaft 111 is adhered to the circuit board a, and the rotating rod 112 is rotated. The rotating rod 112 drives the telescopic component 12 to rotate. When the center line of the telescopic component 12 intersects with the center of the copper hole a1 on the circuit board a, the telescopic sleeve 121 is stretched until the annular sleeve 122 coincides with the center of the copper hole a1; at this time, under the meshing action of the wavy tooth 1 1215 and the wavy tooth 2 1121, the telescopic sleeve 121 will not be able to slide without the action of external pulling force; at this time, the limit rotating block 22 is rotated to the overlapping position of the through arc grooves 1122 on the multiple rotating rods 112, and the limit clamping block 23 is pressed down at this time so that the limit clamping block 23 passes through all the through arc grooves 1122. The arc groove 1122 enters into the clamping block groove 24 to clamp and limit the multiple rotating rods 112, so that the rotating rods 112 cannot rotate, so that the annular sleeve 122 is fixed, and the annular sleeve 122 and the center of the copper hole a1 are always kept in the overlapping position; at this time, the pin b1 of the electronic component b is aligned with the center of the annular sleeve 122 and inserted between the three fixing claws 31, and the pin b1 is squeezed with the compression fillet 311, so that the pin b1 is easier to enter between the three fixing claws 31 to avoid bending of the pin b1, and the pin b1 opens the fixing claw 31. At this time, the positioning pressure rope 123 is squeezed by the fixing claw 31 to shrink through the shrinkage hole 1222 into the expansion air cavity 1221, and under the mutual squeezing action of the Y-shaped structure of the positioning pressure rope 123 and the inner wall of the expansion air cavity 1221, the fixing claw 31 presses and fixes the pin b1 to the center of the copper hole a1.

[0054] During wave soldering, after the solder liquid is in full contact with the three positioning pressure ropes 123, the temperature is transferred to the expansion air cavity 1221 through the positioning pressure ropes 123. The air in the expansion air cavity 1221 is heated to expand and squeeze the clamping block 1211, so that the clamping block 1211 and the clamping groove 1223 are separated, and the telescopic sliding sleeve 121 is pushed out of the expansion air cavity 1221 to the outside of the annular sleeve 122 for a very short distance. Since the width of the clamping block 1211 is greater than the width of the outlet position of the expansion air cavity 1221, the clamping block 1211 is separated from the clamping groove. When the gas no longer squeezes the clamping block 1211, the clamping block 1211 is clamped on the side wall of the expansion air cavity 1221, and the remaining expanded air is discharged from the balancing air hole 1213 through the balancing air hole 1213; at this time, all mechanisms except the fixing mechanism 3, the annular sleeve 122 and its internal structure can be disassembled after welding is completed, and reused to reduce costs, and the pop-up of the telescopic sleeve 121 can be used to quickly determine whether subsequent re-welding is required, and the pin b1 that has not been popped out can be re-welded, thereby reducing the time cost of subsequent inspections and improving welding quality.

[0055] When welding is completed and entering the cooling stage, the outside air enters the expansion air cavity 1221 through the balancing air hole 1213, so that the internal air pressure of the expansion air cavity 1221 remains balanced after the clamping block 1211 pops out, thereby preventing the clamping block 1211 from being re-sucked into the clamping groove 1223 due to the pressure imbalance caused by the drop in temperature in the expansion air cavity 1221.

[0056] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected, and the scope of the present invention to be protected is defined by the attached claims and their equivalents.

Claims

1. A welding jig, characterized in that: The welding fixture comprises a positioning mechanism (1), a limiting mechanism (2) and a fixing mechanism (3); the positioning mechanism (1) comprises a rotating assembly (11) and a telescopic assembly (12); the rotating assembly (11) is connected to a circuit board (a); the telescopic assembly (12) is connected to the rotating assembly (11); the limiting mechanism (2) is connected to the rotating assembly (11); the fixing mechanism (3) is connected to the telescopic assembly (12); when using the welding fixture, the rotating assembly (11) is connected to the circuit board (a) and the rotating assembly (11) is rotated to rotate. The moving component (11) drives the telescopic component (12) to rotate until the center line of the telescopic component (12) intersects with the center of the copper hole (a1) on the circuit board (a), the telescopic component (12) is stretched to a position where it coincides with the copper hole (a1), the limiting mechanism (2) is pressed down so that the limiting mechanism (2) clamps the rotating component (11) to limit the position, the pin (b1) of the electronic component (b) is inserted into the fixing mechanism (3), and the fixing mechanism (3) is squeezed by the pin (b1) to shrink and clamp the pin (b1) of the electronic component (b) toward the center of the copper hole (a1).

2. A welding jig according to claim 1, characterized in that: The rotating assembly (11) comprises a positioning shaft (111) and a rotating rod (112); when the welding fixture is in use, the positioning shaft (111) is connected to a circuit board (a); a plurality of rotating rods (112) are connected to the positioning shaft (111); the telescopic assembly (12) comprises a telescopic sleeve (121), an annular sleeve (122) and a positioning pressure rope (123); the telescopic sleeve (121) is connected to the rotating rod (112); the annular sleeve (122) is connected to the telescopic sleeve (121); and the positioning pressure rope (123) is connected to the annular sleeve (122).

3. A welding jig according to claim 2, characterized in that: An expansion air cavity (1221) is provided in the annular sleeve (122), and three shrinkage holes (1222) are provided in a circumferential array on the inner wall of the annular sleeve (122); the three positioning pressure ropes (123) are installed in the shrinkage holes (1222), and the positioning pressure ropes (123) are Y-shaped structures. When the upper end of the Y-shaped structure is compressed, deformation may occur, and the positioning pressure ropes (123) are made of a high thermal conductivity material.

4. A welding jig according to claim 2, characterized in that: The telescopic sleeve (121) is made of platinum-cured silicone rubber, and a clamping block (1211) is provided at the top of the telescopic sleeve (121); and a clamping groove (1223) is provided at the opening of the expansion air cavity (1221).

5. A welding jig according to claim 4, characterized in that: The top end of the clamping block (1211) is provided with a fitting surface (1212) that fits with the inner wall of the expansion air cavity (1221), and the tail plane end of the clamping block (1211) is provided with a balancing air hole (1213).

6. A welding jig according to claim 4, characterized in that: A telescopic sliding groove (1214) is provided inside the telescopic sliding sleeve (121); a wave tooth 1 (1215) is provided on the telescopic sliding groove (1214); and wave teeth 2 (1121) meshing with the wave teeth 1 (1215) are respectively provided on both sides of the rotating rod (112).

7. A welding jig according to claim 6, characterized in that: The limiting mechanism (2) comprises a limiting rotation groove (21), a limiting rotation block (22), a limiting clamping block (23) and a clamping block groove (24); the limiting rotation groove (21) is arranged on the upper part of the positioning shaft (111); the limiting rotation block (22) is installed in the limiting rotation groove (21); the limiting clamping block (23) is connected to the limiting rotation block (22), and the limiting clamping block (23) is an inverted F-shaped structure; the clamping block groove (24) is arranged on the lower part of the positioning shaft (111), and the upper inner circle of the clamping block groove (24) is provided with a shrinkage fillet (241); and a through arc groove (1122) is arranged on the rotating rod (112).

8. A welding jig according to claim 2, characterized in that: The fixing mechanism (3) comprises a fixing claw (31) and a shielding surface (32); the fixing claw (31) is connected to the positioning pressure rope (123), and the fixing claw (31) is an arc-shaped structure; the shielding surface (32) is connected to the upper end of the annular sleeve (122), and its cross section is an eight-shaped structure, the inner diameter of the shielding surface (32) is larger than the outer diameter of the fixing claw (31), and the upper end surface of the fixing claw (31) is higher than the highest point of the lower end surface of the shielding surface (32).

9. A welding jig according to claim 8, characterized in that: The fixing claw (31) is provided with a compression fillet (311) at the upper end, a drainage fillet (312) at the lower end, and a plurality of convex points (313) on the side wall.

10. A welding jig according to claim 8, characterized in that: The annular sleeve (122) is made of an insulating material that can withstand high temperatures above 240° C.; the lower surface of the shielding surface (32) and the side wall and lower surface of the annular sleeve (122) are all provided with an attachment surface (321).

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