A raw material proportioning device for tin paste production

Abstract

The application discloses a raw material proportioning equipment for tin paste production and belongs to the technical field of mixing devices. In the application, the mixing kettle is provided with a powder inlet on the top, a paste inlet on the top, and a discharge valve on the bottom. The quantitative mechanism comprises a feeding shaft arranged above the mixing kettle, a plurality of quantitative grooves are formed in the outer wall of the feeding shaft around the axis, the anti-sticking mechanism comprises a scraper arranged in the paste inlet, the mixing mechanism comprises a plurality of mixing plates arranged in the mixing kettle, and the divided raw materials and paste-like raw materials are mixed by rotating the mixing plates. The quantitative mechanism, the anti-sticking mechanism and the mixing mechanism are arranged, the accurate fine adjustment of raw material proportioning, the automatic self-cleaning of the feeding channel and the efficient homogenization and defoaming of the materials are realized, the universality of the equipment is improved, the production cost is reduced, and the quality stability of tin paste products is improved.

Description

Technical Field

[0001] This invention belongs to the field of mixing equipment technology, and particularly relates to a raw material proportioning device for solder paste production. Background Technology

[0002] High-lead solder pastes with a lead content (W(Pb)) of over 85%, such as SN5Pb92.5AG5, SN10Pb88AG2, SN5Pb95, and SN10Pb90, are widely used in high-temperature applications of microelectronic packaging. The main characteristics of high-lead solder paste include: 1. Strong wettability, high soldering strength, and good electrical performance; 2. Bright and full solder joints; 3. Low residue and high insulation resistance; 4. High soldering temperature; 5. Minimal collapse, preventing component misalignment. Due to these characteristics, high-lead solder paste is commonly used for packaging and soldering power semiconductors and other components, suitable for power transistors, diodes, transistors, thyristors, rectifiers, and small integrated circuits. High-lead solder not only provides a solid and reliable connection for microelectronic components operating in harsh hot environments, but it is also often used as a high-melting-point alloy in ladder soldering for primary packaging of electronic components and as a die-attachment material for semiconductor chips. It is an extremely important interconnect material in the packaging of key electronic equipment in military and civilian fields such as large IT equipment and network infrastructure, high-power power supplies and switches, automotive electronics, and aerospace.

[0003] In the production process of solder paste, the proportioning and mixing of raw materials are crucial. Traditional proportioning devices are mostly fixed-volume feeding devices. If the powder and paste ratio needs to be changed, the entire feeding assembly often needs to be replaced. The adjustment accuracy is low and the downtime is long, making it difficult to meet the production needs of multiple varieties and small batches. Due to the high viscosity of flux and finished solder paste, they are prone to sticking to the walls of the feeding and conveying pipelines. The residual material not only causes inaccurate feeding, but also may dry and clump over time, blocking the channels and even affecting the purity of subsequent batches of products. Traditional proportioning devices mostly use unidirectional stirring, which makes it difficult to deeply homogenize solder powder and flux with huge density differences. Moreover, air is easily drawn in during high-speed stirring, forming tiny bubbles. These bubbles remain in the solder paste and will expand when heated during reflow soldering, causing voids in the solder joints and affecting the lifespan of electronic products. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of inconvenient proportioning adjustment, easy material adhesion to the wall, and easy generation of air bubbles in traditional proportioning devices, and to propose a raw material proportioning device for solder paste production.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A raw material proportioning device for solder paste production includes a mixing vessel, wherein the top of the mixing vessel has a powder inlet, the top of the mixing vessel has a solder paste inlet, and the bottom of the mixing vessel has a discharge valve; The metering mechanism includes a feeding shaft located above the mixing vessel. The outer wall of the feeding shaft is provided with multiple metering grooves around its axis. The amount of powder injected is adjusted by adjusting the actual volume of the metering grooves. An anti-sticking mechanism includes a scraper disposed inside the paste inlet, which moves back and forth inside the paste inlet to prevent paste-like raw materials from adhering to the inner wall of the paste inlet; The mixing mechanism includes multiple mixing plates located inside the mixing vessel, which mix the dispensed raw materials and the paste-like raw materials by rotating the mixing plates.

[0006] As a further description of the above technical solution: The quantitative mechanism further includes: The injection shell is located at the top of the mixing vessel, and the two ends of the feeding shaft pass through the inner wall of the injection shell on both sides. Guide plates, two of which are located inside the injection shell.

[0007] As a further description of the above technical solution: The quantitative mechanism further includes: Mounting bracket, which is disposed on one side of the injection shell; The first motor is located on one side of the mounting bracket, and its output end is connected to one end of the feeding shaft.

[0008] As a further description of the above technical solution: The quantitative mechanism further includes: A lead screw, one end of which is inserted through the other end of the feeding shaft; A movable seat is provided outside the lead screw, and one side of the movable seat is embedded in the outer wall of the injection shell. A handwheel, which is connected to one end of a lead screw.

[0009] As a further description of the above technical solution: The anti-sticking mechanism further includes: A positioning shell, wherein the positioning shell is disposed at the top of the mixing vessel; Movable blocks, a plurality of the movable blocks are embedded in the outer wall of the positioning shell around the axis of the positioning shell.

[0010] As a further description of the above technical solution: The anti-sticking mechanism further includes: A limiting ring, wherein the limiting ring is disposed outside the positioning shell; A clearance groove is formed on the inner wall of the limiting ring; The first spring is located outside the limiting ring, and its two ends are respectively connected to the corresponding positions of the outer wall of the limiting ring and the outer wall of the positioning shell.

[0011] As a further description of the above technical solution: The anti-sticking mechanism further includes: An insertion tube is provided inside the positioning shell, and the bottom end of the insertion tube is connected to the top of the scraper; The discharge port is located at the top of the scraper. The second spring is located outside the insertion tube, and its two ends are connected to the corresponding positions of the outer wall of the insertion tube and the outer wall of the positioning shell, respectively.

[0012] As a further description of the above technical solution: The mixing mechanism further includes: A protective shell is disposed on the top of the mixing vessel; A central shaft, which is located inside the protective shell; A drive gear, which is rotatably connected to the top of the central shaft; A transmission gear, wherein the transmission gear is rotatably connected to one side of the central shaft via a column; Driven gear, which is rotatably connected to the bottom end of the central shaft.

[0013] As a further description of the above technical solution: The mixing mechanism further includes: The second motor is located at the top of the mixing vessel, and its output end is connected to the top of the drive gear. A first rotating frame is sleeved on the outside of the drive gear, and the first rotating frame is fixedly connected to the drive gear; The first connecting rod has its top end connected to one end of the first rotating frame and its bottom end connected to the top of the mixing plate.

[0014] As a further description of the above technical solution: The mixing mechanism further includes: The second rotating frame is sleeved on the outside of the driven gear, and the second rotating frame is fixedly connected to the driven gear; The second connecting rod has its top end connected to one end of the second rotating frame, and its bottom end connected to a defoamer.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In this invention, by setting a quantitative mechanism, the actual effective volume of the quantitative groove on the feeding shaft can be changed, allowing the operator to make fine adjustments to the volume without replacing the core components according to the strict requirements of different specifications of solder paste for the ratio of solder powder. This ensures the accuracy of the powder and paste ratio and improves the versatility of the equipment.

[0016] 2. In this invention, by setting an anti-sticking mechanism, the inner wall of the solder paste inlet can be automatically cleaned before and after the solder paste is injected by using the reciprocating movement of the scraper. This solves the problem that flux or solder paste base material is prone to adhere to the inner wall of the pipe due to its high viscosity, which leads to poor feeding or cross-contamination. This reduces raw material waste and lowers production costs.

[0017] 3. In this invention, by setting a mixing mechanism, the mixing plate and the defoamer can be rotated in opposite directions. When the mixing plate rotates at the edge, it also has the function of scraping the wall to prevent the material from accumulating in dead corners. The defoamer rotating in opposite directions can quickly break up the bubbles generated during the mixing process, so that the solder powder and flux can reach a highly homogeneous state in a short time. This solves the problem of solder paste oxidation and printing voids caused by bubbles, and improves product quality. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the main structure of a raw material proportioning device for solder paste production proposed in this invention; Figure 2 This is a schematic diagram showing the disassembled structure of a raw material proportioning device for solder paste production proposed in this invention. Figure 3 This is a partial cross-sectional view of the quantitative mechanism of a raw material proportioning device for solder paste production proposed in this invention. Figure 4 This is a partial half-section diagram of the quantitative mechanism of a raw material proportioning device for solder paste production proposed in this invention, taken from another angle. Figure 5 This is a schematic diagram of an anti-sticking mechanism for a raw material proportioning device used in solder paste production, as proposed in this invention. Figure 6 This is a half-sectional schematic diagram of the anti-sticking mechanism of a raw material proportioning equipment for solder paste production proposed in this invention; Figure 7 This is a schematic diagram of the mixing mechanism of a raw material proportioning device for solder paste production proposed in this invention; Figure 8 This is a partial cross-sectional schematic diagram of the mixing mechanism of a raw material proportioning device for solder paste production proposed in this invention.

[0019] Legend: 1. Mixing vessel; 2. Powder inlet; 3. Paste inlet; 4. Discharge valve; 5. Metering mechanism; 501. Injection shell; 502. Guide plate; 503. Mounting bracket; 504. Feeding shaft; 505. Metering groove; 506. First motor; 507. Moving base; 508. Lead screw; 509. Handwheel; 6. Anti-sticking mechanism; 601. Positioning shell; 602. Moving block; 603. Limiting ring; 604. Relief groove; 605. 606. Spring; 607. Insertion tube; 608. Scraper; 609. Discharge port; 6000. Second spring; 701. Mixing mechanism; 702. Protective shell; 703. Central shaft; 704. Drive gear; 705. Transmission gear; 706. Driven gear; 707. First rotating frame; 708. First connecting rod; 709. Mixing plate; 710. Second rotating frame; 711. Second connecting rod; 712. Defoamer; 713. Second motor. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figures 1-8 The present invention provides a technical solution: a raw material proportioning device for solder paste production, including a mixing tank 1, a powder inlet 2 at the top of the mixing tank 1, a paste inlet 3 at the top of the mixing tank 1, and a discharge valve 4 at the bottom of the mixing tank 1; The metering mechanism 5 includes a feeding shaft 504 located above the mixing vessel 1. The outer wall of the feeding shaft 504 is provided with multiple metering grooves 505 around its axis. The amount of powder injected is adjusted by adjusting the actual volume of the metering grooves 505. The anti-sticking mechanism 6 includes a scraper 607 disposed inside the paste inlet 3, which moves back and forth inside the paste inlet 3 to prevent the paste material from adhering to the inner wall of the paste inlet 3; The mixing mechanism 7 includes multiple mixing plates 708 disposed inside the mixing vessel 1, which mix the packaged raw materials and the paste raw materials by rotating the mixing plates 708.

[0022] The quantification mechanism 5 also includes: The injection shell 501 is located at the top of the mixing vessel 1, and the two ends of the feeding shaft 504 are respectively inserted through the inner wall of the injection shell 501. Guide plates 502, two guide plates 502 are located inside the injection shell 501.

[0023] The quantification mechanism 5 also includes: Mounting bracket 503 is located on one side of injection shell 501; The first motor 506 is located on one side of the mounting bracket 503, and the output end of the first motor 506 is connected to one end of the feeding shaft 504.

[0024] The quantification mechanism 5 also includes: A lead screw 508 is inserted at one end of a feed shaft 504 at the other end. The movable seat 507 is located outside the lead screw 508, and one side of the movable seat 507 is embedded in the outer wall of one side of the injection shell 501. Handwheel 509 is connected to one end of lead screw 508.

[0025] Specifically: the handwheel 509 is rotated, which drives the lead screw 508 to rotate synchronously. The external thread on the outer wall of the lead screw 508 meshes with the internal thread on the inner wall of the feeding shaft 504, causing the moving seat 507 to move along the direction of the lead screw 508. The cross-sectional shape of the protrusion of the moving seat 507 is the same as the cross-sectional shape of the metering trough 505, so that the actual effective volume of the metering trough 505 is changed when the moving seat 507 moves. The powdered raw material is put in from the top of the injection shell 501 and falls into the metering trough 505 along the direction of the guide plate 502. After the metering trough 505 is filled, the first motor 506 drives the feeding shaft 504 to rotate. The feeding shaft 504 causes the metering trough 505 to rotate downward and inject the powdered raw material in the metering trough 505 into the mixing vessel 1 through the powder inlet 2.

[0026] It should be noted that the selection of the first motor 506 and the control unit in the above description are selected as needed. This part is well-known technology in the field and will not be described in detail here.

[0027] Please see Figures 5-6 The anti-stick mechanism 6 also includes: Positioning shell 601 is located at the top of mixing vessel 1; Movable blocks 602, multiple movable blocks 602 are embedded in the outer wall of the positioning shell 601 around the axis of the positioning shell 601.

[0028] The anti-stick mechanism 6 also includes: Limiting ring 603 is located outside the positioning shell 601; The clearance groove 604 is formed on the inner wall of the limiting ring 603; The first spring 605 is located outside the limiting ring 603, and its two ends are respectively connected to the corresponding positions of the outer wall of the limiting ring 603 and the outer wall of the positioning shell 601.

[0029] The anti-stick mechanism 6 also includes: Insertion tube 606 is located inside positioning shell 601, and the bottom end of insertion tube 606 is connected to the top of scraper 607. The discharge port 608 is located at the top of the scraper 607; The second spring 609 is located outside the insertion tube 606, and its two ends are connected to the corresponding positions of the outer wall of the insertion tube 606 and the outer wall of the positioning shell 601, respectively.

[0030] Specifically: In the initial state, the first spring 605 is in a compressed state, pulling the limiting ring 603 upward. The first spring 605 is compressed, and the top of the clearance groove 604 coincides with the position of the moving block 602. The second spring 609 pushes the insertion tube 606 upward through its own elastic force. The groove on the outer wall of the insertion tube 606 squeezes the moving block 602 outward, causing the moving block 602 to enter the clearance groove 604, releasing the locking of the moving block 602 on the insertion tube 606. The insertion tube 606 drives the scraper 607 to move upward synchronously. The side wall of the scraper 607 scrapes over the inner wall of the paste inlet 3 to clean the previous... The paste-like material adhering to the inner wall of the inlet 3 is injected. The injection tube of the paste-like material is inserted into the insertion tube 606. The injection tube presses down on the insertion tube 606, and the second spring 609 is compressed again. The groove on the outer wall of the insertion tube 606 is aligned with the moving block 602 again. The first spring 605 pushes the limiting ring 603 downward by its own elastic force. When the top of the positioning groove 604 pushes the moving block 602 inward, one side of the moving block 602 is inserted into the groove on the outer wall of the insertion tube 606, and the position of the insertion tube 606 is locked. The injection tube injects the paste-like material, which is then injected into the mixing vessel 1 through the outlet 608.

[0031] Please see Figures 7-8 The mixing mechanism 7 also includes: Protective shell 701 is located on top of mixing vessel 1; Central shaft 702, which is located inside the protective housing 701; Drive gear 703 is rotatably connected to the top end of central shaft 702; The transmission gear 704 is rotatably connected to one side of the central shaft 702 via a column. Driven gear 705 is rotatably connected to the bottom end of central shaft 702.

[0032] The mixing mechanism 7 also includes: The second motor 712 is located at the top of the mixing vessel 1, and the output end of the second motor 712 is connected to the top of the drive gear 703. The first rotating frame 706 is sleeved on the outside of the drive gear 703, and the first rotating frame 706 is fixedly connected to the drive gear 703. The first connecting rod 707 has its top end connected to one end of the first rotating frame 706, and its bottom end connected to the top of the mixing plate 708.

[0033] The mixing mechanism 7 also includes: The second rotating frame 709 is sleeved on the outside of the driven gear 705, and the second rotating frame 709 is fixedly connected to the driven gear 705. The second connecting rod 710 has its top end connected to one end of the second rotating frame 709, and its bottom end connected to a defoamer 711.

[0034] Specifically: the second motor 712 drives the drive gear 703 to rotate through its output end. The drive gear 703 drives the driven gear 705 to rotate in the opposite direction through the transmission gear 704. The first rotating frame 706 is sleeved on the outside of the drive gear 703 and fixedly connected to it. The first rotating frame 706 rotates synchronously with the drive gear 703. The first rotating frame 706 drives the three first connecting rods 707 to rotate synchronously. The first connecting rods 707 drive the mixing plate 708 to rotate synchronously, mixing the powdered raw materials and the paste-like raw materials. The rotation trajectory of 8 passes through the edge of the mixing vessel 1. The mixing plate 708 scrapes the inner wall of the mixing vessel 1 through its edge, thus playing a scraping role. The second rotating frame 709 is sleeved on the outside of the driven gear 705 and is fixedly connected to the driven gear 705. The second rotating frame 709 rotates synchronously with the driven gear 705. The second rotating frame 709 drives the three second connecting rods 710 to rotate synchronously. The second connecting rods 710 drive the defoamer 711 to rotate synchronously. The defoamer 711 rotates in the opposite direction to the rotation direction of the mixing plate 708, breaking up and defoaming the bubbles in the paste.

[0035] It should be noted that the selection of the second motor 712 and the control unit in the above description are selected as needed. This part is well-known technology in the field and will not be described in detail here.

[0036] It should be noted that the drive gear 703, transmission gear 704 and driven gear 705 in the above description are all bevel gears. The pitch cone surface of the bevel gear coincides with the vertex of the friction wheel. Power transmission is achieved through pure rolling, which can realize power transmission between two intersecting shafts. It is suitable for vertical shaft transmission scenarios. This part is a well-known technology in the field and will not be described in detail here.

[0037] Working principle: During use, the operator turns the handwheel 509 to adjust the amount of powdered raw material to be mixed each time according to the actual production needs. After adjustment, the operator starts the first motor 506 to inject the powdered raw material into the mixing vessel 1 through the powder inlet 2. Then, the operator pulls the limit ring 603 upward and inserts the paste material injection tube into the insertion tube 606 to inject the paste material into the mixing vessel 1 through the paste inlet 3. After both raw materials are put into the mixing vessel 1, the operator turns off the first motor 506 and starts the second motor 712 to make the mixing plate 708 and the defoamer 711 rotate relative to each other. After the mixing is completed, the operator turns off the second motor 712 and discharges the mixed solder paste through the discharge valve 4.

[0038] In this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A raw material proportioning device for solder paste production, comprising a mixing tank (1), characterized in that, The mixing vessel (1) has a powder inlet (2) at the top, a paste inlet (3) at the top, and a discharge valve (4) at the bottom. The metering mechanism (5) includes a feeding shaft (504) located above the mixing vessel (1). The outer wall of the feeding shaft (504) is provided with multiple metering grooves (505) around its axis. The amount of powder injected is adjusted by adjusting the actual volume of the metering grooves (505). The anti-sticking mechanism (6) includes a scraper (607) disposed in the paste inlet (3), which moves back and forth inside the paste inlet (3) to prevent the paste material from adhering to the inner wall of the paste inlet (3); The mixing mechanism (7) includes multiple mixing plates (708) located inside the mixing vessel (1), which mix the packaged raw materials and the paste raw materials by rotating the mixing plates (708).

2. The raw material proportioning equipment for solder paste production according to claim 1, characterized in that, The quantitative mechanism (5) further includes: The injection shell (501) is located at the top of the mixing vessel (1), and the two ends of the feeding shaft (504) are respectively inserted through the inner wall of the injection shell (501); Guide plates (502), two of the guide plates (502) are disposed inside the injection shell (501).

3. The raw material proportioning equipment for solder paste production according to claim 2, characterized in that, The quantitative mechanism (5) further includes: Mounting bracket (503), which is located on one side of the injection shell (501); The first motor (506) is located on one side of the mounting bracket (503), and the output end of the first motor (506) is connected to one end of the feeding shaft (504).

4. The raw material proportioning equipment for solder paste production according to claim 2, characterized in that, The quantitative mechanism (5) further includes: A lead screw (508), one end of which is inserted through the other end of a feeding shaft (504); A movable seat (507) is provided outside the lead screw (508), and one side of the movable seat (507) is embedded in the outer wall of one side of the injection shell (501); Handwheel (509), which is connected to one end of lead screw (508).

5. The raw material proportioning equipment for solder paste production according to claim 1, characterized in that, The anti-sticking mechanism (6) further includes: Positioning shell (601), the positioning shell (601) is disposed on the top of the mixing vessel (1); Movable blocks (602), a plurality of said movable blocks (602) are embedded in the outer wall of the positioning shell (601) around the axis of the positioning shell (601).

6. The raw material proportioning equipment for solder paste production according to claim 5, characterized in that, The anti-sticking mechanism (6) further includes: A limiting ring (603) is provided outside the positioning shell (601); A relief groove (604) is formed on the inner wall of the limiting ring (603); The first spring (605) is located outside the limiting ring (603), and the two ends of the first spring (605) are respectively connected to the corresponding positions of the outer wall of the limiting ring (603) and the outer wall of the positioning shell (601).

7. A raw material proportioning device for solder paste production according to claim 5, characterized in that, The anti-sticking mechanism (6) further includes: An insertion tube (606) is provided inside the positioning shell (601), and the bottom end of the insertion tube (606) is connected to the top of the scraper (607); The discharge port (608) is located at the top of the scraper (607); The second spring (609) is located outside the insertion tube (606), and the two ends of the second spring (609) are respectively connected to the corresponding positions of the outer wall of the insertion tube (606) and the outer wall of the positioning shell (601).

8. The raw material proportioning equipment for solder paste production according to claim 1, characterized in that, The mixing mechanism (7) further includes: A protective shell (701) is provided on the top of the mixing vessel (1); A central shaft (702) is located inside the protective shell (701); A drive gear (703) is rotatably connected to the top end of the central shaft (702); A transmission gear (704) is rotatably connected to one side of a central shaft (702) via a column; Driven gear (705) is rotatably connected to the bottom end of central shaft (702).

9. A raw material proportioning device for solder paste production according to claim 8, characterized in that, The mixing mechanism (7) further includes: The second motor (712) is located on the top of the mixing vessel (1), and the output end of the second motor (712) is connected to the top of the drive gear (703); The first rotating frame (706) is sleeved on the outside of the drive gear (703), and the first rotating frame (706) is fixedly connected to the drive gear (703); The first connecting rod (707) has its top end connected to one end of the first rotating frame (706) and its bottom end connected to the top of the mixing plate (708).

10. A raw material proportioning device for solder paste production according to claim 1, characterized in that, The mixing mechanism (7) further includes: The second rotating frame (709) is sleeved on the outside of the driven gear (705), and the second rotating frame (709) is fixedly connected to the driven gear (705); The second connecting rod (710) has its top end connected to one end of the second rotating frame (709), and the bottom end of the second connecting rod (710) is connected to a defoamer (711).

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