A mixing device for preparing lead-free solder paste

Abstract

The present invention discloses a mixing device for preparing lead-free solder paste, which relates to the technical field related to solder paste. The mixing device includes a mixing cylinder, a mixing component, a discharging component and a discharging port. A cylinder cover is arranged on the mixing cylinder. A stirring rod is rotatably installed in the mixing cylinder, and the bottom end of the stirring rod is fixedly connected to the output end of a first driving motor fixedly installed on the mixing cylinder. A concave disc is fixedly installed on the lower surface of the cylinder cover, and the stirring rod is rotatably connected to the concave disc. Two feeding ports are formed in the cylinder cover, and a feeding pipe and a feeding hopper are respectively and fixedly installed at the two feeding ports. In the present invention, the stirring blades rotate to mix and stir the materials in the mixing cylinder. While the shaft sleeve rotates, under the combined action of the track groove and the limiting rod, the shaft sleeve and the stirring blades will move up and down, so that the stirring blades can rotate and stir while moving up and down to rotate and stir the materials at different heights in the mixing cylinder. The mixing effect is good, the stirring is uniform, and the mixing efficiency is high.

Description

Technical Field

[0001] The present invention relates to the technical field of solder paste, and particularly to a mixing device for preparing lead-free solder paste. Background Art

[0002] Solder paste, also known as tin paste, is a gray paste. Solder paste is a new type of welding material that emerged with the advent of SMT. It is made by mixing solder powder, flux, and other surfactants, polyamide wax, etc., and is mainly used for welding electronic components such as surface resistors, capacitors, and ICs on PCBs in the SMT industry.

[0003] During the production of lead-free solder paste, it is necessary to stir the component materials. Most of the existing stirring and mixing devices stir the materials in a single direction by driving the stirring blades with a motor, and the stirring height is a fixed height, and the materials can only be stirred at the same horizontal height. As a result, some materials with larger particle sizes are likely to deposit on the side wall and bottom of the stirring cylinder, the mixing is insufficient and the mixing method is relatively single. The materials always move in a single direction following the stirring direction, making it difficult to improve the dispersibility between the component materials, and it is difficult for the substances in the component materials to be fully mixed, reducing the mixing effect of the materials and the mixing efficiency. In addition, during the preparation process, it is not convenient to break up some agglomerated or bonded materials. Since the added raw materials are prone to agglomerate due to oxidation, storage, etc., the added raw materials dissolve slowly, and the powdered solder powder is prone to agglomerate due to oxidation or combination with moisture in the air, resulting in the need for a long stirring time during subsequent mixing, with low practicability and reduced mixing efficiency. Summary of the Invention

[0004] To solve the defects existing in the prior art, the present invention provides a mixing device for preparing lead-free solder paste.

[0005] To solve the above technical problems, the present invention provides the following technical solutions:

[0006] A mixing device for preparing lead-free solder paste of the present invention includes the following steps:

[0007] S1. Prepare materials: Lead-free solder paste is composed of solder powder, activator, polyamide wax, polymerized rosin, disproportionated rosin, and organic solvent. The mass percentages of each component are: solder powder: 85% - 90%, disproportionated rosin: 2% - 4%, polymerized rosin: 2% - 4%, activator: 0.1% - 0.4%, polyamide wax: 0.5% - 1%, organic solvent: the balance;

[0008] S2. Mixing: Weigh each material according to the component ratio. Add polymerized rosin and disproportionated rosin into the mixing barrel and heat to 130 °C, then cool down to 100 °C. Next, add the activator and organic solvent, and stir and mix the materials in the mixing barrel through the mixing component. After cooling to 70 °C, add polyamide wax, stir and mix again, and then cool to obtain the soldering paste;

[0009] S3. Obtaining the finished product: Add the solder powder into the mixing barrel and stir and mix it with the soldering paste, then let it stand and cool to obtain the lead-free solder paste;

[0010] S4. Taking out the finished product: Discharge the finished product from the mixing barrel through the discharging component via the discharging port.

[0011] As a preferred technical solution of the present invention, a lid is provided on the mixing barrel. A stirring rod is rotatably installed in the mixing barrel, and the bottom end of the stirring rod is fixedly connected to the output end of a first driving motor fixedly installed on the mixing barrel. A concave disc is fixedly installed on the lower surface of the lid, and the stirring rod is rotatably connected to the concave disc. Two feeding ports are opened on the lid, and a feeding pipe and a feeding hopper are respectively fixedly installed at the two feeding ports. The top of the feeding hopper is communicated with a grinding box, and a grinding component is arranged in the grinding box;

[0012] The mixing component includes an elliptical disc fixedly installed on the stirring rod. A number of moving rods are slidably installed on the concave disc in a circumferential array. A clamping sleeve is fixedly installed at one end of each moving rod close to the elliptical disc, and the clamping sleeve is used in cooperation with the elliptical disc. The other end of the moving rod is provided with an auxiliary mixing unit, and a stirring unit is arranged on the stirring rod;

[0013] The grinding component includes a grinding unit arranged in the grinding box and a dispersing unit arranged in the feeding hopper and linked with the grinding unit;

[0014] The discharging port is arranged at the bottom of the mixing barrel, and a control valve is arranged in the discharging port.

[0015] As a preferred technical solution of the present invention, the stirring unit includes a bushing slidably installed on the stirring rod, and a number of stirring blades are fixedly installed on the outer surface of the bushing. A track groove is opened on the outer surface of the stirring rod, and the track groove is composed of a number of V-shaped grooves connected end to end. The connection points of the heads and tails of the number of V-shaped grooves and each bending point are all in smooth transition. A connecting plate is fixedly installed on the lower surface of the concave disc, and a limiting rod matched with the track groove is fixedly installed at the bottom of the connecting plate. The limiting rod is arranged in the track groove in a matching manner. A number of clamping blocks are fixedly installed on the outer surface of the stirring rod, and a number of clamping grooves used in cooperation with the clamping blocks are opened on the bushing. The clamping blocks are slidably attached to the clamping grooves on the same side.

[0016] As a preferred technical solution of the present invention, a limiting sleeve is slidably mounted on the outer surface of the moving rod, and the limiting sleeve is fixedly connected to the lower surface of the cylinder cover.

[0017] As a preferred technical solution of the present invention, the stirring blades are arranged obliquely, and the shape of the stirring blades is oval.

[0018] As a preferred technical solution of the present invention, the auxiliary mixing unit includes a toothed plate fixedly mounted on the moving rod. A rotating rod is rotatably mounted on the cylinder cover on the same side of the toothed plate. A column gear meshing with the toothed plate on the same side is fixedly mounted on the rotating rod. An installation cylinder is fixedly mounted on the rotating rod. Two rotating shafts are symmetrically and rotatably mounted on the installation cylinder. One end of the rotating rod extends into the installation cylinder and is fixedly mounted with a first bevel gear. Second bevel gears are fixedly mounted at the ends of the two rotating shafts close to each other. The two second bevel gears are symmetrically arranged and both mesh with the first bevel gear. A stirring blade is fixedly mounted at the end of the rotating shaft away from the installation cylinder. The shape of the stirring blade is anchor-shaped. Springs are sleeved on the outer surfaces of each moving rod. The two ends of the spring are respectively fixedly connected to the clamping sleeve and the concave disc on the same side.

[0019] As a preferred technical solution of the present invention, the grinding unit includes two roller shafts rotatably mounted on the grinding box. Grinding rollers are fixedly mounted on the two roller shafts. The two grinding rollers are used in cooperation. A second driving motor is fixedly mounted on one side of the grinding box. First transmission gears are fixedly mounted on the outer surfaces of the two roller shafts. The two first transmission gears mesh with each other. The output end of the second driving motor is fixedly connected to the end of one of the roller shafts. A cleaning unit for cleaning the grinding rollers is provided at the end of each roller shaft away from the transmission gear. Two guide plates are symmetrically and obliquely mounted in the grinding box.

[0020] As a preferred technical solution of the present invention, the two cleaning units are symmetrically arranged. The cleaning unit includes a driving disc fixedly mounted on the roller shaft. A connecting column is eccentrically mounted on the driving disc. A slide rail is slidably mounted on the outer surface of the connecting column. A toothed block is rotatably mounted on the grinding box on the same side of the slide rail. The slide rail is fixedly connected to the toothed block on the same side. A threaded rod is rotatably mounted in the grinding box on the same side of the toothed block. One end of the threaded rod extends out of the grinding box and is fixedly mounted with a second transmission gear meshing with the toothed block. The two grinding rollers are respectively located between the two threaded rods. A cleaning brush is threadedly mounted on the threaded outer surface of the threaded rod. The brush surface of the cleaning brush fits the outer surface of the grinding roller on the same side. A guide rod is fixedly mounted in the grinding box on the same side of the threaded rod. The cleaning brush is slidably connected to the guide rod on the same side.

[0021] As a preferred technical solution of the present invention, the dispersion unit includes a worm gear rotatably installed in the grinding box. Belt pulleys are fixedly installed on the outer surfaces of the worm gear and one of the roller shafts. A belt is sleeved between the two belt pulleys and they are connected by belt drive. A support disc is fixedly installed in the feeding port on the same side of the grinding box, and a transmission shaft is rotatably installed on the support disc. A worm wheel meshing with the worm gear is fixedly installed at the top of the transmission shaft. A number of striking hammers are fixedly installed on the outer surface of the transmission shaft;

[0022] A number of arc-shaped scrapers are fixedly installed at the bottom of the transmission shaft, and the arc-shaped scrapers are adapted to the inner wall of the feeding hopper.

[0023] As a preferred technical solution of the present invention, the discharging assembly includes a semi-circular arc-shaped plate fixedly installed at the bottom of the stirring rod and a vertical scraper fixedly installed on the arc-shaped plate. The bottom of the arc-shaped plate is tangent to the lower surface of the inner wall of the stirring cylinder, and the vertical scraper is attached to the inner wall of the stirring cylinder.

[0024] The beneficial effects of the present invention are:

[0025] 1. For this mixing device for preparing lead-free solder paste, by setting the stirring unit, the first driving motor drives the stirring rod to rotate. The rotation of the stirring rod drives the sleeve and the stirring blades to rotate under the cooperation of the clamping block and the clamping groove. The rotation of the stirring blades mixes and stirs the materials in the stirring cylinder. While the sleeve is rotating, it will drive the sleeve and the stirring blades to move up and down under the cooperation of the track groove and the limiting rod. Therefore, it can realize the rotation and stirring of the stirring blades while moving up and down to rotate and stir the materials at different heights in the stirring cylinder. The mixing effect is good, the stirring is uniform, and the mixing efficiency is high.

[0026] 2. For this mixing device for preparing lead-free solder paste, by setting the auxiliary mixing unit, the rotation of the stirring rod will drive the elliptical disc to rotate. The rotation of the elliptical disc drives the toothed plate to move. The movement of the toothed plate drives the rotating rod and the first bevel gear to rotate through the column gear, and further drives the rotating shaft and the stirring blades to rotate. The rotation of the stirring blades stirs the materials in the stirring cylinder in another direction. Therefore, it can stir and mix the materials in the stirring cylinder in multiple directions and at multiple levels, increase the diversity of mixing, further improve the material mixing efficiency, and convert the tangential flow in the stirring cylinder into axial flow or radial flow, making the mixing between different component materials more sufficient and further improving the mixing effect.

[0027] 3. The mixing device for preparing the lead-free solder paste, by setting the stirring blades and stirring vanes, the stirring blades are arranged obliquely so as to convey the materials deposited at the bottom of the mixing cylinder upward, further improving the dispersibility of the materials in the mixing cylinder, enhancing the mixing effect of the materials, making the mixing of the materials more uniform. The shape of the stirring blades is set as an ellipse. The eddy current generated by the elliptical stirring blades is stronger, which can better mix the various materials in the mixing cylinder evenly. The shape of the stirring vanes is an anchor shape, which can generate strong shearing force and stirring force, and accelerate the mixing among the materials.

[0028] 4. The mixing device for preparing the lead-free solder paste, by setting the grinding unit, the second driving motor drives the two grinding rollers to rotate towards each other to perform pre-crushing and grinding on the materials, and can grind and crush some large agglomerated and caked materials contained in the materials, facilitating subsequent stirring and mixing.

[0029] 5. The mixing device for preparing the lead-free solder paste, by setting the cleaning unit, while the roller shaft rotates, it drives the driving disk to rotate. The rotation of the driving disk drives the threaded rod to rotate. The rotation of the threaded rod drives the cleaning brush to move accordingly and perform a cleaning operation on the grinding roller, sweeping down the materials attached to the grinding roller, which can ensure the grinding effect of the grinding roller and avoid waste of materials caused by the retention of materials on the grinding roller.

[0030] 6. The mixing device for preparing the lead-free solder paste, by setting the dispersion unit, while the roller shaft rotates, it drives the worm to rotate through the belt pulley and belt. The rotation of the worm drives the transmission shaft and the striking hammer to rotate through the worm gear, so as to perform further crushing and dispersing operations on the materials ground by the grinding roller, and can fully grind and crush the materials to be crushed, facilitating the rapid fusion of the materials. While the transmission shaft rotates, it drives the arc-shaped scraper to move accordingly. The rotation of the arc-shaped scraper can scrape off the materials attached to the inner wall of the hopper, avoiding the influence of the remaining materials on the next mixing operation and also avoiding waste of materials.

[0031] 7. The mixing device for preparing the lead-free solder paste, by setting the discharging assembly, while the stirring rod rotates, it drives the arc-shaped plate and the vertical scraper to rotate accordingly. The rotation of the arc-shaped plate and the vertical scraper can scrape off the materials attached to the side wall and the inner wall of the mixing cylinder, improving the mixing effect of the materials. When it is necessary to discharge the well-mixed materials in the mixing cylinder, through the rotation of the arc-shaped scraper and the vertical scraper, the discharge of the materials from the mixing cylinder can be accelerated, and at the same time, waste of materials and corrosion of the mixing cylinder caused by the retention of the remaining materials on the inner wall of the mixing cylinder can be avoided. Description of the Drawings

[0032] The drawings are used to provide further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0033] Figure 1 It is a schematic structural diagram of the mixing drum of a mixing device for preparing lead-free solder paste according to the present invention;

[0034] Figure 2 It is a schematic cross-sectional structural diagram of the mixing drum of a mixing device for preparing lead-free solder paste according to the present invention;

[0035] Figure 3 It is a schematic structural diagram of the mixing unit of a mixing device for preparing lead-free solder paste according to the present invention;

[0036] Figure 4 is Figure 3 The enlarged schematic diagram of the structure at A in

[0037] Figure 5 It is a schematic structural diagram of the elliptical disk of a mixing device for preparing lead-free solder paste according to the present invention;

[0038] Figure 6 It is a schematic structural diagram of the track groove of a mixing device for preparing lead-free solder paste according to the present invention;

[0039] Figure 7 It is a schematic diagram of the plane expansion of the bushing of a mixing device for preparing lead-free solder paste according to the present invention;

[0040] Figure 8 It is a schematic structural diagram of the auxiliary mixing unit of a mixing device for preparing lead-free solder paste according to the present invention;

[0041] Figure 9 It is a schematic cross-sectional structural diagram of the grinding box of a mixing device for preparing lead-free solder paste according to the present invention;

[0042] Figure 10 It is a schematic structural diagram of the grinding assembly of a mixing device for preparing lead-free solder paste according to the present invention;

[0043] Figure 11 It is a schematic structural diagram of the cleaning unit of a mixing device for preparing lead-free solder paste according to the present invention.

[0044] In the figure: 1, mixing drum; 2, drum cover; 3, mixing rod; 4, first drive motor; 5, concave disc; 6, mixing assembly; 61, elliptical disc; 62, moving rod; 63, bushing; 64, auxiliary mixing unit; 641, toothed plate; 642, rotating rod; 643, spur gear; 644, mounting cylinder; 645, rotating shaft; 646, first bevel gear; 647, second bevel gear; 648, mixing blade; 649, spring; 6410, limiting sleeve; 65, mixing unit; 651, bushing; 652, mixing blade; 653, track groove; 6531, V-shaped groove; 654, limiting rod; 655, clamping block; 656, clamping groove; 7, blanking pipe; 8, feeding port; 9, grinding assembly; 91, grinding unit; 911, roller shaft; 912, grinding roller; 913, second drive motor; 914, first transmission gear; 915, cleaning unit; 9151, drive disc; 9152, connecting column; 9153, slide rail; 9154, toothed block; 9155, second transmission gear; 9156, cleaning brush; 9157, threaded rod; 92, dispersion unit; 921, worm; 922, pulley; 923, belt; 924, support disc; 925, transmission shaft; 926, worm gear; 927, striking hammer; 928, arc-shaped scraper; 10, hopper; 11, grinding box; 12, discharging assembly; 121, arc-shaped plate; 122, vertical scraper; 13, discharging port. Specific embodiments

[0045] The following is a description of the preferred embodiments of the present invention with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0046] Embodiment: As Figures 1 to 11 shown, a mixing device for preparing lead-free solder paste according to the present invention includes the following steps:

[0047] S1. Prepare materials: The lead-free solder paste is composed of solder powder, activator, polyamide wax, polymerized rosin, disproportionated rosin and organic solvent. The mass percentages of each component are: solder powder: 85%-90%, disproportionated rosin: 2%-4%, polymerized rosin: 2%-4%, activator: 0.1%-0.4%, polyamide wax: 0.5%-1%, organic solvent: the balance;

[0048] S2. Mixing: Weigh each material according to the component ratio, add the polymerized rosin and disproportionated rosin into the mixing drum 1 and heat to 130°C, then cool to 100°C, and then add the activator and organic solvent. Stir and mix the materials in the mixing drum 1 through the mixing assembly 6. After cooling to 70°C, add the polyamide wax, stir and mix again, and then cool to obtain the soldering paste;

[0049] S3. Obtain the finished product: Add the solder powder into the mixing cylinder 1 and mix it evenly with the soldering paste, then let it stand and cool to obtain the lead-free soldering paste;

[0050] S4. Take out the finished product: Discharge the finished product from the mixing cylinder 1 through the discharging assembly 12 via the discharging port 13.

[0051] Among them, as Figures 1 to 11 shown, a cylinder cover 2 is arranged on the mixing cylinder 1, a stirring rod 3 is rotatably installed in the mixing cylinder 1, and the bottom end of the stirring rod 3 is fixedly connected to the output end of a first driving motor 4 fixedly installed on the mixing cylinder 1. A concave disc 5 is fixedly installed on the lower surface of the cylinder cover 2, and the stirring rod 3 is rotatably connected to the concave disc 5. Two feeding ports 8 are opened on the cylinder cover 2, and a feeding pipe 7 and a feeding hopper 10 are respectively fixedly installed at the two feeding ports 8. The top of the feeding hopper 10 is communicated with a grinding box 11, and a grinding assembly 9 is arranged in the grinding box 11; The mixing assembly 6 includes an elliptical disc 61 fixedly installed on the stirring rod 3. A plurality of moving rods 62 are slidably installed on the concave disc 5 in a circumferential array. A clamping sleeve 63 is fixedly installed at one end of each moving rod 62 close to the elliptical disc 61. The clamping sleeve 63 is used in cooperation with the elliptical disc 61. The other end of the moving rod 62 is provided with an auxiliary mixing unit 64, and a stirring unit 65 is arranged on the stirring rod 3; The grinding assembly 9 includes a grinding unit 91 arranged in the grinding box 11 and a dispersing unit 92 arranged in the feeding hopper 10 and linked with the grinding unit 91; The discharging port 13 is arranged at the bottom of the mixing cylinder 1, and a control valve is arranged in the discharging port 13.

[0052] Among them, as Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 shown, the stirring unit 65 includes a bushing 651 slidably installed on the stirring rod 3. A plurality of stirring blades 652 are fixedly installed on the outer surface of the bushing 651. A track groove 653 is opened on the outer surface of the stirring rod 3. The track groove 653 is composed of a plurality of V-shaped grooves 6531 connected end to end. The connection points of the heads and tails of the plurality of V-shaped grooves 6531 and each bending point are all in smooth transition. A connecting plate is fixedly installed on the lower surface of the concave disc 5, and a limiting rod 654 matched with the track groove 653 is fixedly installed at the bottom of the connecting plate. The limiting rod 654 is arranged in the track groove 653 in a matching manner. A plurality of clamping blocks 655 are fixedly installed on the outer surface of the stirring rod 3. A plurality of clamping grooves 656 used in cooperation with the clamping blocks 655 are opened on the bushing 651. The clamping blocks 655 are slidably attached in the clamping grooves 656 on the same side.

[0053] Specifically, the first drive motor 4 drives the stirring rod 3 to rotate. The stirring rod 3 rotates and drives the bushing 651 and the stirring blade 652 to rotate following it under the cooperation of the clamping block 655 and the clamping groove 656. The stirring blade 652 rotates to mix and stir the materials in the mixing drum 1. While the bushing 651 rotates, it will drive the bushing 651 and the stirring blade 652 to move up and down under the cooperation of the track groove 653 and the limiting rod 654. Thus, it can be realized that while the stirring blade 652 rotates and stirs, it moves up and down to rotate and stir the materials at different heights in the mixing drum 1, with good mixing effect, uniform stirring, and high mixing efficiency.

[0054] Further, as Figure 2 and Figure 3 shown, the stirring blade 652 is arranged obliquely, and the shape of the stirring blade 652 is oval. The oblique arrangement of the stirring blade 652 can convey the materials deposited at the bottom of the mixing drum 1 upward, further improving the dispersibility of the materials in the mixing drum 1, enhancing the mixing effect of the materials, making the materials more evenly mixed. The shape of the stirring blade 652 is set as oval, and the eddy current generated by the oval stirring blade 652 is stronger, which can better mix the various materials in the mixing drum 1 evenly.

[0055] Among them, as Figure 2 , Figure 3 , Figure 5 and Figure 8 shown, the auxiliary mixing unit 64 includes a toothed plate 641 fixedly installed on the moving rod 62. A rotating rod 642 is rotatably installed on the cover 2 of the same side of the toothed plate 641, and a column gear 643 meshing with the toothed plate 641 on the same side is fixedly installed on the rotating rod 642. An installation cylinder 644 is fixedly installed on the rotating rod 642, and two rotating shafts 645 are symmetrically and rotatably installed on the installation cylinder 644. One end of the rotating rod 642 extends into the installation cylinder 644 and is fixedly installed with a first bevel gear 646. Second bevel gears 647 are fixedly installed at the mutually approaching ends of the two rotating shafts 645. The two second bevel gears 647 are symmetrically arranged and both mesh with the first bevel gear 646. Stirring blades 648 are fixedly installed at the ends of the rotating shafts 645 away from the installation cylinder 644. The shape of the stirring blade 648 is anchor-shaped. Springs 649 are sleeved on the outer surfaces of each moving rod 62, and the two ends of each spring 649 are respectively fixedly connected with the sleeve 63 and the concave disc 5 on the same side.

[0056] Specifically, while the stirring rod 3 rotates to drive the stirring blade 652 to stir the materials in the stirring cylinder 1, it will also drive the elliptical disk 61 to rotate. During the rotation of the elliptical disk 61, it squeezes the sleeve 63 and the spring 649. The sleeve 63 is pressed to drive the moving rod 62 to move. The movement of the moving rod 62 drives the toothed plate 641 to move accordingly. The movement of the toothed plate 641 drives the rotating rod 642 to rotate through the column gear 643. The rotation of the rotating rod 642 drives the first bevel gear 646 to rotate accordingly. The rotation of the first bevel gear 646 drives the rotating shaft 645 and the stirring blade 648 to rotate through the second bevel gear 647. The rotation of the stirring blade 648 stirs the materials in the stirring cylinder 1 in another direction, so as to stir and mix the materials in the stirring cylinder 1 in multiple directions and at multiple levels, increase the diversity of mixing, further improve the mixing efficiency of the materials, and convert the tangential flow in the stirring cylinder 1 into axial flow or radial flow, increase the turbulence degree in the stirring cylinder 1, make the mixing between different components more sufficient, and further improve the mixing effect. The spring 649 can make the sleeve 63 fit tightly with the elliptical disk 61 under the action of its own elasticity.

[0057] Among them, as Figure 2 、 Figure 3 and Figure 5 shown, a limit sleeve 6410 is slidably installed on the outer surface of the moving rod 62, and the limit sleeve 6410 is fixedly connected to the lower surface of the cylinder cover 2. By setting the limit sleeve 6410 to limit the movement of the moving rod 62, it is avoided that the moving rod 62 deviates and shakes during the movement, and further improves the stability of the movement of the moving rod 62.

[0058] Among them, as Figure 1 、 Figure 9 、 Figure 10 and Figure 11 shown, the grinding unit 91 includes two roller shafts 911 rotatably installed on the grinding box 11. Grinding rollers 912 are fixedly installed on both roller shafts 911. The two grinding rollers 912 are used in cooperation with each other. A second driving motor 913 is fixedly installed on one side of the grinding box 11. First transmission gears 914 are fixedly installed on the outer surfaces of both roller shafts 911. The two first transmission gears 914 are meshed with each other. The output end of the second driving motor 913 is fixedly connected to the end of one of the roller shafts 911. A cleaning unit 915 for cleaning the grinding roller 912 is provided at each end of each roller shaft 911 away from the transmission gear. Two guide plates are symmetrically and obliquely installed in the grinding box 11.

[0059] Specifically, the second driving motor 913 drives the roller shaft 911 and the grinding roller 912 on the same side to rotate. The rotation of the grinding roller 912 drives the other grinding roller 912 to rotate in the opposite direction through the first transmission gear 914, and pre-crush and grind the materials, so that some large, sticky and agglomerated materials contained in the materials can be ground and broken, which is convenient for subsequent stirring and mixing.

[0060] Among them, as Figure 1 , Figure 9 , Figure 10 and Figure 11 shown, the two cleaning units 915 are symmetrically arranged. The cleaning unit 915 includes a driving disk 9151 fixedly installed on the roller shaft 911. An eccentric connecting column 9152 is installed on the driving disk 9151. A slide rail 9153 is slidably installed on the outer surface of the connecting column 9152. A toothed block 9154 is rotatably installed on the grinding box 11 on the same side of the slide rail 9153. The slide rail 9153 is fixedly connected to the toothed block 9154 on the same side. A threaded rod 9157 is rotatably installed in the grinding box 11 on the same side of the toothed block 9154. One end of the threaded rod 9157 extends outside the grinding box 11 and is fixedly installed with a second transmission gear 9155 meshing with the toothed block 9154. The two grinding rollers 912 are respectively located between the two threaded rods 9157. A cleaning brush 9156 is threadedly installed on the threaded outer surface of the threaded rod 9157. The brushing surface of the cleaning brush 9156 is attached to the outer surface of the grinding roller 912 on the same side. A guide rod is fixedly installed in the grinding box 11 on the same side of the threaded rod 9157. The cleaning brush 9156 is slidably connected to the guide rod on the same side.

[0061] Specifically, when the roller shaft 911 rotates, it drives the driving disk 9151 to rotate. The rotation of the driving disk 9151 drives the toothed block 9154 to reciprocally rotate through the connecting column 9152 and the slide rail 9153. The rotation of the toothed block 9154 drives the threaded rod 9157 to rotate through the second transmission gear 9155. The rotation of the threaded rod 9157 drives the cleaning brush 9156 to move accordingly and perform a cleaning operation on the grinding roller 912, sweeping the materials attached to the grinding roller 912. This can ensure the grinding effect of the grinding roller 912 and avoid waste of materials caused by the remaining materials on the grinding roller 912. The guide rod can limit and guide the movement of the cleaning brush 9156 to ensure the stability of the cleaning brush 9156 when moving on the threaded rod 9157.

[0062] Among them, as Figure 1 , Figure 9 , Figure 10 and Figure 11 shown, the dispersion unit 92 includes a worm 921 rotatably installed in the grinding box 11. Belt pulleys 922 are fixedly installed on the outer surfaces of the worm 921 and one of the roller shafts 911. A belt 923 is sleeved between the two belt pulleys 922 and they are connected by belt transmission. A support disk 924 is fixedly installed in the feeding port 8 on the same side of the grinding box 11. A transmission shaft 925 is rotatably installed on the support disk 924. A worm wheel 926 meshing with the worm 921 is fixedly installed at the top of the transmission shaft 925. A number of striking hammers 927 are fixedly installed on the outer surface of the transmission shaft 925;

[0063] A number of arc-shaped scraping plates 928 are fixedly installed at the bottom of the transmission shaft 925, and the arc-shaped scraping plates 928 are adapted to the inner wall of the feeding hopper 10.

[0064] Specifically, while the roller shaft 911 rotates, it drives the worm 921 to rotate through the belt pulley 922 and the belt 923. The rotation of the worm 921 drives the transmission shaft 925 to rotate through the worm gear 926. The rotation of the transmission shaft 925 drives the striking hammer 927 to rotate accordingly, so that the material ground by the grinding roller 912 can be further broken and dispersed, and the material to be broken can be fully ground and broken, facilitating the rapid fusion of the material.

[0065] While the transmission shaft 925 rotates, it drives the arc-shaped scraping plates 928 to move accordingly. The rotation of the arc-shaped scraping plates 928 can scrape off the material adhering to the inner wall of the feeding hopper 10, avoiding the influence of the residual material on the next mixing operation and also avoiding material waste.

[0066] Among them, as Figure 2 and Figure 3 shown, the discharging assembly 12 includes an arc-shaped plate 121 fixedly installed at the bottom of the stirring rod 3 and shaped like a semi-circle, and a vertical scraping plate 122 fixedly installed on the arc-shaped plate 121. The bottom of the arc-shaped plate 121 is tangent to the lower surface of the inner wall of the mixing cylinder 1, and the vertical scraping plate 122 is in contact with the inner wall of the mixing cylinder 1. While the stirring rod 3 rotates, it drives the arc-shaped plate 121 and the vertical scraping plate 122 to rotate accordingly. The rotation of the arc-shaped plate 121 and the vertical scraping plate 122 can scrape off the material adhering to the side wall and the inner wall of the mixing cylinder 1, improving the mixing effect of the material. When it is necessary to discharge the well-mixed material in the mixing cylinder 1, through the rotation of the arc-shaped scraping plates 928 and the vertical scraping plates 122, the material can be discharged from the mixing cylinder 1 more quickly, and at the same time, material waste and the remaining material adhering to the inner wall of the mixing cylinder 1 can be avoided, preventing corrosion of the mixing cylinder 1.

[0067] During operation, each material is weighed according to the component ratio, and then each raw material is pre-treated. The raw material that needs to be crushed and ground is put into the mixing cylinder 1 through the grinding box 11, and the material that does not need to be crushed is put into the mixing cylinder 1 through the feeding pipe 7. The second driving motor 913 drives the roller shaft 911 and the grinding roller 912 on the same side to rotate. The rotation of the grinding roller 912 drives the other grinding roller 912 to rotate in opposite directions through the first transmission gear 914, pre-crushing and grinding the material, so that some large lumps of sticky and agglomerated materials contained in the material can be ground and broken. While the roller shaft 911 rotates, it drives the worm 921 to rotate through the belt pulley 922 and the belt 923. The rotation of the worm 921 drives the transmission shaft 925 to rotate through the worm gear 926. The rotation of the transmission shaft 925 drives the striking hammer 927 to rotate accordingly, so that the material ground by the grinding roller 912 can be further broken and dispersed, and the material to be broken can be fully ground and broken, facilitating the rapid fusion of the material.

[0068] First, polymerized rosin and disproportionated rosin are added into the mixing drum 1 and heated to 130°C, then cooled to 100°C, and then an activator and an organic solvent are added, and the first driving motor 4 is started. The first driving motor 4 drives the stirring rod 3 to rotate, and the stirring rod 3 rotates, and the sleeve 651 and the stirring blade 652 are driven to rotate with the cooperation of the block 655 and the slot 656. The stirring blade 652 rotates to mix and stir the materials in the mixing drum 1. When the sleeve 651 rotates, the sleeve 651 and the stirring blade 652 are driven to move up and down under the cooperation of the track groove 653 and the limit rod 654, so that the stirring blade 652 can rotate and stir while moving up and down to rotate and stir the materials at different heights in the mixing drum 1. The stirring rod 3 rotates and drives the stirring blade 652 to stir the materials in the mixing drum 1, and at the same time drives the elliptical The circular disk 61 rotates, and the elliptical disk 61 squeezes the ferrule 63 and the spring 649 during the rotation. The ferrule 63 is pressed to drive the moving rod 62 to move, and the movement of the moving rod 62 drives the tooth plate 641 to follow the movement. The movement of the tooth plate 641 drives the rotating rod 642 to rotate through the column gear 643, and the rotation of the rotating rod 642 drives the first bevel gear 646 to follow the rotation. The first bevel gear 646 rotates through the second bevel gear 647 to drive the rotating shaft 645 and the stirring blade 648 to rotate. The stirring blade 648 rotates to stir the material in the mixing drum 1 in another direction, so that the material in the mixing drum 1 can be stirred and mixed in multiple directions and at multiple levels, increasing the diversity of mixing and further improving the material mixing efficiency. After stirring and mixing, wait until it is cooled to 70°C, add polyamide wax, stir and mix again, and cool to obtain solder paste;

[0069] Then add the solder powder to be ground into the grinding box 11, grind and disperse it fully, stir and mix it with the flux paste, let it stand and cool, and obtain the lead-free solder paste;

[0070] After the stirring and mixing is completed, the discharge port 13 is opened through the control valve, and the stirring rod 3 rotates while driving the arc plate 121 and the vertical scraper 122 to rotate accordingly. The rotation of the arc plate 121 and the vertical scraper 122 can scrape off the materials attached to the side wall and the inner wall of the mixing drum 1, which can speed up the discharge of the materials from the mixing drum 1, and at the same time avoid the waste of materials and the residual materials adhering to the inner wall of the mixing drum 1 and causing corrosion to the mixing drum 1.

[0071] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A mixing device for preparing lead-free solder paste, characterized in that, It includes a mixing drum (1), a mixing component (6), a discharging component (12) and a discharging port (13). A drum cover (2) is arranged on the mixing drum (1). A stirring rod (3) is rotatably installed in the mixing drum (1), and the bottom end of the stirring rod (3) is fixedly connected to the output end of a first driving motor (4) fixedly installed on the mixing drum (1). A concave disc (5) is fixedly installed on the lower surface of the drum cover (2), and the stirring rod (3) is rotatably connected to the concave disc (5). Two feeding ports (8) are formed in the drum cover (2), and a feeding pipe (7) and a feeding hopper (10) are respectively fixedly installed at the two feeding ports (8). The top of the feeding hopper (10) is communicated with a grinding box (11), and a grinding component (9) is arranged in the grinding box (11); The mixing component (6) includes an elliptical disc (61) fixedly installed on the stirring rod (3). A plurality of moving rods (62) are slidably installed on the concave disc (5) in a circumferential array. A clamping sleeve (63) is fixedly installed at one end of each moving rod (62) close to the elliptical disc (61), and the clamping sleeve (63) is used in cooperation with the elliptical disc (61). An auxiliary mixing unit (64) is arranged at the other end of the moving rod (62), and a stirring unit (65) is arranged on the stirring rod (3); The grinding component (9) includes a grinding unit (91) arranged in the grinding box (11) and a dispersing unit (92) arranged in the feeding hopper (10) and interlocked with the grinding unit (91); The discharging port (13) is arranged at the bottom of the mixing drum (1), and a control valve is arranged in the discharging port (13).

2. The mixing device for preparing lead-free solder paste according to claim 1, characterized in that, The stirring unit (65) includes a sleeve (651) slidably installed on the stirring rod (3). A plurality of stirring blades (652) are fixedly installed on the outer surface of the sleeve (651). A track groove (653) is formed on the outer surface of the stirring rod (3). The track groove (653) is composed of a plurality of V-shaped grooves (6531) connected end to end. The connection points of the plurality of V-shaped grooves (6531) and each bending point are all in smooth transition. A connecting plate is fixedly installed on the lower surface of the concave disc (5), and a limiting rod (654) used in cooperation with the track groove (653) is fixedly installed at the bottom of the connecting plate. A plurality of clamping blocks (655) are fixedly installed on the outer surface of the stirring rod (3). A plurality of clamping grooves (656) used in cooperation with the clamping blocks (655) are formed on the sleeve (651), and the clamping blocks (655) fit and slide in the clamping grooves (656) on the same side.

3. The mixing device for preparing lead-free solder paste according to claim 2, characterized in that, The stirring blades (652) are arranged obliquely, and the shape of the stirring blades (652) is elliptical.

4. A mixing device for preparing lead-free solder paste according to claim 1, characterized in that, The auxiliary mixing unit (64) includes a toothed plate (641) fixedly installed on the moving rod (62). A rotating rod (642) is rotatably installed on the cylinder cover (2) on the same side of the toothed plate (641). A column gear (643) meshing with the toothed plate (641) on the same side is fixedly installed on the rotating rod (642). An installation cylinder (644) is fixedly installed on the rotating rod (642). Two rotating shafts (645) are symmetrically and rotatably installed on the installation cylinder (644). One end of the rotating rod (642) extends into the installation cylinder (644) and a first bevel gear (646) is fixedly installed. Second bevel gears (647) are fixedly installed at the ends of the two rotating shafts (645) close to each other. The two second bevel gears (647) are symmetrically arranged and both mesh with the first bevel gear (646). A stirring blade (648) is fixedly installed at the end of the rotating shaft (645) away from the installation cylinder (644). The shape of the stirring blade (648) is anchor-shaped. A spring (649) is sleeved on the outer surface of each moving rod (62). The two ends of the spring (649) are respectively fixedly connected to the clamping sleeve (63) and the concave disc (5) on the same side.

5. The mixing device for preparing lead-free solder paste according to claim 4, characterized in that, A limiting sleeve (6410) is slidably installed on the outer surface of the moving rod (62), and the limiting sleeve (6410) is fixedly connected to the lower surface of the cylinder cover (2).

6. The mixing device for preparing lead-free solder paste according to claim 5, characterized in that, The grinding unit (91) includes two roller shafts (911) rotatably installed on the grinding box (11). Grinding rollers (912) are fixedly installed on the two roller shafts (911). The two grinding rollers (912) are used in cooperation. A second driving motor (913) is fixedly installed on one side of the grinding box (11). First transmission gears (914) are fixedly installed on the outer surfaces of the two roller shafts (911). The two first transmission gears (914) mesh with each other. The output end of the second driving motor (913) is fixedly connected to the end of one of the roller shafts (911). A cleaning unit (915) for cleaning the grinding roller (912) is arranged at the end of each roller shaft (911) away from the transmission gear. Two guide plates are symmetrically and obliquely installed in the grinding box (11).

7. A mixing device for preparing lead-free solder paste according to claim 6, characterized in that, The two cleaning units (915) are symmetrically arranged, and the cleaning units (915) include a driving disk (9151) fixedly mounted on a roller shaft (911), a connecting column (9152) eccentrically mounted on the driving disk (9151), a slide rail (9153) slidably mounted on the outer surface of the connecting column (9152), a tooth block (9154) rotatably mounted on the grinding box (11) on the same side of the slide rail (9153), the slide rail (9153) being fixedly connected to the tooth block (9154) on the same side, and the tooth block (9154) 4) A threaded rod (9157) is rotatably installed in the grinding box (11) on the same side, and one end of the threaded rod (9157) extends outside the grinding box (11) and is fixedly installed with a second transmission gear (9155) meshing with the tooth block (9154), the two grinding rollers (912) are respectively located between the two threaded rods (9157), and a cleaning brush (9156) is threadedly installed on the threaded outer surface of the threaded rod (9157), and the brush surface of the cleaning brush (9156) is in contact with the outer surface of the grinding roller (912) on the same side; A guide rod is fixedly installed in the grinding box (11) on the same side as the threaded rod (9157), and the cleaning brush (9156) is slidably connected to the guide rod on the same side.

8. The mixing device for preparing lead-free solder paste according to claim 6, wherein, The dispersion unit (92) comprises a worm (921) rotatably mounted in a grinding box (11); a pulley (922) is fixedly mounted on the outer surface of the worm (921) and one of the rollers (911); a belt (923) is sleeved between the two pulleys (922) and the two pulleys are connected by the belt (923); a support plate (924) is fixedly mounted in a feeding port (8) on the same side of the grinding box (11); a transmission shaft (925) is rotatably mounted on the support plate (924); a worm wheel (926) meshing with the worm (921) is fixedly mounted on the top end of the transmission shaft (925); and a plurality of striking hammers (927) are fixedly mounted on the outer surface of the transmission shaft (925); A plurality of arc-shaped scrapers (928) are fixedly mounted on the bottom of the transmission shaft (925), and the arc-shaped scrapers (928) are adapted to the inner wall of the lower hopper (10).

9. The mixing device for preparing lead-free solder paste according to claim 1, characterized in that, The discharge assembly (12) comprises a semicircular arc plate (121) fixedly mounted on the bottom of the stirring rod (3) and a vertical scraper (122) fixedly mounted on the arc plate (121); the bottom of the arc plate (121) is tangent to the lower surface of the inner wall of the stirring drum (1), and the vertical scraper (122) is in contact with the inner wall of the stirring drum (1).

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