Equipment for preparing lead-free paste for QFN (Quad Flat No-lead) chip

Abstract

The invention discloses equipment for preparing lead-free paste for a QFN (Quad Flat No-lead) chip. The equipment comprises a base; the first stand column is fixedly arranged on the rear side of the top end of the base. The control cabinet is fixedly arranged on the rear side of the first stand column. The longitudinal lifting machine is arranged on the front side of the first stand column; the stirring moving mechanism is arranged on the front side of the longitudinal elevator; the stirring cylinders are arranged at the top end of the base, and the number of the stirring cylinders is two; and the discharging mechanism is arranged at the bottom end of the stirring barrel. According to the equipment for preparing the lead-free paste for the QFN chip, by arranging the stirring moving mechanism, the two stirring barrels can be moved and limited, so that when one stirring barrel is controlled to carry out stirring processing, the lead-free paste in the other stirring barrel is taken, and the production efficiency of the lead-free paste is improved.

Description

Technical Field

[0001] This invention relates to the field of lead-free paste preparation technology, specifically to an apparatus for preparing lead-free paste for QFN chips. Background Technology

[0002] Lead-free solder paste is an environmentally friendly electronic soldering material. Its main components include metal alloys such as tin, silver, copper, and nickel, as well as auxiliary materials such as resin and active flux. Compared with traditional lead-containing soldering flux, lead-free solder paste has higher environmental protection and safety, and causes less pollution to workers' health and the environment. In the world of electronics manufacturing, solder paste plays an indispensable role—it acts as a bridge, cleverly connecting electronic components to circuit boards. The process of preparing lead-free solder paste involves mixing and stirring flux with solder powder and onion powder, and then quantitatively dispensing it. Although existing preparation equipment can automatically stir lead-free solder paste, it usually dispenses the material directly from the bottom of the mixing drum, which occupies the stirring equipment and reduces production efficiency. Furthermore, during the stirring process, the flux at the bottom outlet cannot be fully mixed with the solder powder, and the high viscosity of lead-free solder paste makes dispensing difficult. Summary of the Invention

[0003] The purpose of this invention is to provide an apparatus for preparing lead-free solder paste for QFN chips, in order to solve the problems in the prior art of low preparation efficiency of lead-free solder paste, inability of flux to be fully mixed with solder powder at the bottom outlet during the stirring process, and high viscosity of lead-free solder paste, which makes discharge difficult.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an apparatus for preparing lead-free paste for QFN chips, comprising: a base, a first column, a control cabinet, a longitudinal lift, a stirring and moving mechanism, a stirring cylinder, and a discharging mechanism; the first column is fixedly disposed on the rear side of the top of the base; the control cabinet is fixedly disposed on the rear side of the first column; the longitudinal lift is disposed on the front side of the first column; the stirring and moving mechanism is disposed on the front side of the longitudinal lift; the stirring cylinder is disposed on the top of the base, and the number of the stirring cylinders is two; the discharging mechanism is disposed on the bottom end of the stirring cylinder.

[0005] Preferably, the stirring mechanism includes: a first support frame, fixedly mounted on the front lifting end of the longitudinal lift; a riser, fixedly mounted on the bottom end of the first support frame; a cover plate, fixedly mounted on the bottom end of the riser; a motor, fixedly mounted on the top end of the first support frame, the motor being electrically connected to the control cabinet; a rotating rod, the output end of the motor extending out of the bottom end of the first support frame and locked with a coupling, the rotating rod being inserted into the inner cavity of the riser, and the bottom end of the rotating rod extending out of the bottom end of the cover plate; and a stirring rod, the bottom end of the rotating rod being fixedly mounted with a stirring rod.

[0006] Preferably, the first support frame is located at the front bottom end of the longitudinal lift, and the longitudinal lift can drive the first support frame to move upward until the stirring rod is moved out of the stirring drum.

[0007] Preferably, the stirring mechanism further includes: support wheels, a plurality of support wheels are fixedly provided on the outer wall of the stirring cylinder, and limit grooves are opened on both the front and rear sides of the top of the base in the left and right direction, and the support wheels are located in the limit grooves; positioning blocks, positioning blocks are fixedly provided on the outer side of the support wheels; bolts are screwed to the top of the positioning blocks, and a plurality of positioning holes are opened on the top of the base, and the bolts are adapted to be inserted into the positioning holes at corresponding positions.

[0008] Preferably, the discharge mechanism includes: a second column, with the second column fixedly installed at both the left and right ends of the rear top of the base; a second support frame, fixedly installed at the front of the second column; a hydraulic cylinder, fixedly installed at the top of the second support frame; and a pressure plate, with the bottom end of the hydraulic cylinder extending out of the bottom end of the second support frame and fixedly installed thereon.

[0009] Preferably, the pressure plate is located directly above one of the mixing cylinders, and the pressure plate can be fitted and inserted into the inner cavity of the mixing cylinder.

[0010] Preferably, the discharge mechanism further includes: a discharge cylinder, fixedly disposed at the bottom center of the mixing cylinder; a discharge bend, fixedly disposed at the bottom of the discharge cylinder; a discharge valve, screwed to the front side of the discharge bend; a rotating shaft, rotatably connected to the outer wall of the discharge cylinder; a cam, one end of the rotating shaft extending into the inner cavity of the discharge cylinder and fixedly disposed thereon; a top plate, inserted into the inner cavity of the discharge cylinder, and the top of the top plate contacting the top of the cam; a cover, fixedly disposed at the top of the top plate, a through hole being opened at the bottom of the discharge cylinder, and the cover being adapted to be inserted into the inner cavity of the through hole; a limiting rod, limiting rods fixedly disposed on both the left and right sides of the bottom of the mixing cylinder, and the limiting rods being located inside the discharge cylinder, and the top plate being adapted to be fitted with the limiting rods; and a sealing gasket, fixedly disposed at the bottom of the mixing cylinder, and located between the mixing cylinder and the top plate, and the sealing gasket being sleeved with the limiting rod.

[0011] Preferably, the far hub end of the cam contacts the bottom end of the top plate.

[0012] Preferably, the cap and the bottom of the inner cavity of the stirring cylinder are located on the same plane.

[0013] The apparatus for preparing lead-free paste for QFN chips proposed in this invention has the following advantages: 1. The present invention has a stirring and moving mechanism that can limit the movement of two stirring drums, thereby taking lead-free paste from the other stirring drum while controlling one stirring drum to stir and process, so as to improve the production efficiency of lead-free paste. 2. The present invention has a discharge mechanism that can control the up and down movement of the cap to close and open the through hole, so as to fully stir the lead-free paste in the mixing drum and avoid leakage. By controlling the pressure plate to move downward into the mixing drum and squeeze the lead-free paste, the lead-free paste is scraped and squeezed out to ensure the smooth discharge of the lead-free paste and improve the discharge effect. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 For the present invention Figure 1 Enlarged view of point A in the image; Figure 3 This is a front sectional view of the riser of the present invention; Figure 4 This is a front sectional view of the discharge pipe of the present invention; Figure 5 This is a schematic diagram of the cam structure of the present invention.

[0015] In the diagram: 1. Base; 2. First column; 3. Control cabinet; 4. Longitudinal lifting mechanism; 5. Mixing and moving mechanism; 51. First support frame; 52. Riser; 53. Cover plate; 54. Motor; 55. Rotating rod; 56. Mixing rod; 57. Support wheel; 58. Limiting groove; 59. Positioning block; 510. Bolt; 511. Positioning hole; 6. Mixing drum; 7. Discharge mechanism; 71. Second column; 72. Second support frame; 73. Hydraulic cylinder; 74. Pressure plate; 75. Discharge cylinder; 76. Discharge bend; 77. Discharge valve; 78. Rotating shaft; 79. Cam; 710. Top plate; 711. Cover; 712. Limiting rod; 713. Sealing gasket; 714. Through hole. Detailed Implementation

[0016] 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.

[0017] Please see Figure 1-5 The present invention provides a technical solution: a device for preparing lead-free paste for QFN chips, comprising: a base 1, a first column 2, a control cabinet 3, a longitudinal lifting machine 4, a stirring and moving mechanism 5, a stirring cylinder 6, and a discharging mechanism 7; The first column 2 is fixedly installed on the rear side of the top of the base 1, the control cabinet 3 is fixedly installed on the rear side of the first column 2, the longitudinal lift 4 is installed on the front side of the first column 2, the stirring and moving mechanism 5 is installed on the front side of the longitudinal lift 4, the stirring drum 6 is installed on the top of the base 1, and there are two stirring drums 6. The discharge mechanism 7 is installed at the bottom of the stirring drum 6.

[0018] As a preferred embodiment, the stirring mechanism 5 further includes: a first support frame 51, a riser 52, a cover plate 53, a motor 54, a rotating rod 55, a stirring rod 56, a support wheel 57, a limiting groove 58, a positioning block 59, a bolt 510, and a positioning hole 511. In order to seal and stir the flux in the mixing drum 6, the first support frame 51 is fixedly installed at the front lifting end of the longitudinal lifting machine 4, the riser 52 is fixedly installed at the bottom end of the first support frame 51, the cover plate 53 is fixedly installed at the bottom end of the riser 52, the motor 54 is fixedly installed at the top end of the first support frame 51, the motor 54 is electrically connected to the control cabinet 3, the output end of the motor 54 extends out of the bottom end of the first support machine 51 and is locked with a rotating rod 55 by a coupling, the rotating rod 55 is inserted into the inner cavity of the riser 52, and the bottom end of the rotating rod 55 extends out of the bottom end of the cover plate 53. The bottom end of the rotating rod 55 is fixedly installed with a stirring rod 56. The cover plate 53 can seal the inside of the mixing drum 6.

[0019] In order to move the stirring rod 56 out of the mixing drum 6, the first support frame 51 is located at the bottom front of the longitudinal elevator 4, and the longitudinal elevator 4 can drive the first support frame 51 to move upward until the stirring rod 56 is moved out of the mixing drum 6.

[0020] In order to limit the position of the support wheel 57, several support wheels 57 are fixedly installed on the outer wall of the mixing drum 6. Limiting grooves 58 are opened on both the front and rear sides of the top of the base 1 along the left and right directions, and the support wheel 57 is located in the limiting groove 58. A positioning block 59 is fixedly installed on the outer side of the support wheel 57. The bolt 510 is screwed to the top of the positioning block 59. Several positioning holes 511 are opened on the top of the base 1, and the bolt 510 is adapted to be inserted into the positioning hole 511 at the corresponding position.

[0021] As a preferred embodiment, the discharge mechanism 7 further includes: a second column 71, a second support frame 72, a hydraulic cylinder 73, a pressure plate 74, a discharge cylinder 75, a discharge bend 76, a discharge valve 77, a rotating shaft 78, a cam 79, a top plate 710, a cover 711, a limit rod 712, a sealing gasket 713, and a through hole 714. To facilitate the extrusion of lead-free paste from the mixing drum 6, a second column 71 is fixedly installed on both the left and right sides of the rear top of the base 1. A second support frame 72 is fixedly installed on the front side of the second column 71. A hydraulic cylinder 73 is fixedly installed on the top of the second support frame 72. The bottom end of the hydraulic cylinder 73 extends out of the bottom end of the second support frame 72 and is fixedly installed with a pressure plate 74. The hydraulic cylinder 73 is electrically connected to the control cabinet 3. The hydraulic cylinder 73 can push the pressure plate 74 downward until the pressure plate 74 is inserted into the mixing drum 6 and the pressure plate 74 squeezes the lead-free paste downward.

[0022] As a preferred embodiment, the pressure plate 74 is located directly above one of the mixing drums 6, and the pressure plate 74 can be fitted and inserted into the inner cavity of the mixing drum 6, and the pressure plate 74 can move downward into the mixing drum 6.

[0023] To facilitate the sealing and opening of the bottom of the mixing drum 6, the discharge cylinder 75 is fixedly installed at the middle of the bottom end of the mixing drum 6, the discharge bend 76 is fixedly installed at the bottom end of the discharge cylinder 75, the discharge valve 77 is screwed to the front side of the discharge bend 76, the rotating shaft 78 is rotatably connected to the outer wall of the discharge cylinder 75, one end of the rotating shaft 78 extends into the inner cavity of the discharge cylinder 75 and is fixedly provided with a cam 79, one side of the far hub end of the cam 79 is flat so that the cam 79 can contact and limit the contact with the top plate 710, one end of the rotating shaft 78 is provided with a handle so that the rotating shaft 78 can rotate, the top plate 710 is inserted into the inner cavity of the discharge cylinder 75, and the top plate 710 contacts the top end of the cam 79; To ensure a strong seal at the bottom of the mixing drum 6, a cover 711 is fixedly installed at the top of the top plate 710. A through hole 714 is provided at the bottom of the discharge cylinder 75, and the cover 711 is fitted into the inner cavity of the through hole 714. Limiting rods 712 are fixedly installed on both the left and right sides of the bottom of the mixing drum 6, and the limiting rods 712 are located inside the discharge cylinder 75. The top plate 710 is fitted into the limiting rods 712. A sealing gasket 713 is fixedly installed at the bottom of the mixing drum 6, and is located between the mixing drum 6 and the top plate 710. The sealing gasket 713 is sleeved with the limiting rod 712.

[0024] In order to place the top plate 710 against the bottom of the mixing drum 6, the far hub end of the cam 79 contacts the bottom end of the top plate 710.

[0025] As a preferred option, the cap 711 is further positioned on the same plane as the bottom of the inner cavity of the mixing tank 6, so as to fully stir the flux at the bottom of the mixing tank 6.

[0026] Its detailed connection method is a well-known technology in this field. The following mainly introduces the working principle and process, and the specific work is as follows.

[0027] Step 1: Start the control cabinet 3. The control cabinet 3 can drive the longitudinal lift 4 to start, so as to move the first support frame 51 upward, thereby moving the cover plate 53 upward through the riser 52, so as to move the stirring rod 56 out of the stirring drum 75, and add flux and solder powder into the stirring drum 6. Step 2: Move the stirring rod 56 into the stirring drum 75, start the motor 54, and the motor 54 can drive the rotating rod 55 to rotate, so that the rotating rod 55 drives the stirring rod 56 to rotate, thereby enabling the stirring rod 56 to stir the flux and solder powder. After stirring and preparation, control the stirring rod 56 to rise and scrape the lead-free paste on the stirring rod 56 into the stirring drum 75. Step 3: Rotate bolt 510 to move bolt 510 upward, thereby disengaging bolt 510 from the inner cavity of positioning hole 511, thus releasing the restriction on mixing drum 6. Under the restriction of support wheel 57 and limiting groove 58, mixing drum 6 is moved to one side to below pressure plate 74, and the other mixing drum 6 is moved to below cover plate 53. This allows for simultaneous mixing and lead-free paste discharge in both mixing drums 6, thus accelerating production efficiency. Step 4: Activate hydraulic cylinder 73 to push pressure plate 74 downward until it is inserted into mixing drum 6. Pressure plate 74 then squeezes the lead-free paste downward, opening discharge valve 77. Rotate shaft 78 clockwise to rotate the far hub end of cam 79 downward. Under the gravity of the lead-free paste in mixing drum 6, cap 711 is pushed downward, causing top plate 710 to move downward under the restriction of limit rod 712. This opens through hole 714, allowing lead-free paste to fall into inlet / outlet cylinder 75. The lead-free paste is then discharged through discharge bend 76 and discharge valve 77. Under the pressure of cap 711, lead-free paste is not only scraped from the inner wall of mixing drum 6, but also extruded more quickly, ensuring smooth discharge and improving discharge efficiency, which is beneficial for widespread application.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An apparatus for preparing lead-free paste for QFN chips, characterized in that, include: Base (1); The first column (2) is fixedly installed on the rear side of the top of the base (1); The control cabinet (3) is fixedly installed on the rear side of the first column (2); A longitudinal lifting platform (4) is installed on the front side of the first column (2); A stirring and moving mechanism (5) is located on the front side of the longitudinal elevator (4); A stirring cylinder (6) is disposed at the top of the base (1), and there are two stirring cylinders (6); The discharge mechanism (7) is located at the bottom end of the mixing drum (6).

2. The apparatus for preparing lead-free paste for QFN chips according to claim 1, characterized in that: The stirring mechanism (5) includes: The first support frame (51) is fixedly installed at the front lifting end of the longitudinal elevator (4); The riser (52) is fixedly installed at the bottom end of the first support frame (51); A cover plate (53) is fixedly installed at the bottom end of the riser (52); The motor (54) is fixedly mounted on the top of the first support frame (51), and the motor (54) is electrically connected to the control cabinet (3); Rotary rod (55), the output end of the motor (54) extends out of the bottom end of the first support machine (51) and is locked with a coupling. The rotating rod (55) is inserted into the inner cavity of the riser (52) and the bottom end of the rotating rod (55) extends out of the bottom end of the cover plate (53). A stirring rod (56) is fixedly provided at the bottom end of the rotating rod (55).

3. The apparatus for preparing lead-free paste for QFN chips according to claim 2, characterized in that: The first support frame (51) is located at the front bottom of the longitudinal elevator (4), and the longitudinal elevator (4) can drive the first support frame (51) to move upward until the stirring rod (56) moves out of the stirring drum (6).

4. The apparatus for preparing lead-free paste for QFN chips according to claim 3, characterized in that: The stirring mechanism (5) further includes: Support wheels (57), a number of support wheels (57) are fixedly provided on the outer wall of the stirring cylinder (6), and limit grooves (58) are opened on both the front and rear sides of the top of the base (1) along the left and right directions, and the support wheels (57) are located in the limit grooves (58). Positioning block (59): A positioning block (59) is fixedly provided on the outer side of the support wheel (57). Bolt (510) is screwed to the top of the positioning block (59). The top of the base (1) is provided with a plurality of positioning holes (511), and the bolt (510) is adapted to be inserted into the positioning hole (511) at the corresponding position.

5. The apparatus for preparing lead-free paste for QFN chips according to claim 1, characterized in that: The discharge mechanism (7) includes: The second column (71) is fixedly installed on both the left and right sides of the rear top of the base (1). The second support frame (72) is fixedly installed on the front side of the second column (71); A hydraulic cylinder (73) is fixedly mounted on the top of the second support frame (72); The pressure plate (74) is fixedly installed on the bottom end of the hydraulic cylinder (73) extending out from the bottom end of the second support frame (72).

6. The apparatus for preparing lead-free paste for QFN chips according to claim 5, characterized in that: The pressure plate (74) is located directly above one of the stirring cylinders (6), and the pressure plate (74) can be fitted and inserted into the inner cavity of the stirring cylinder (6).

7. The apparatus for preparing lead-free paste for QFN chips according to claim 6, characterized in that: The discharge mechanism (7) also includes: The discharge cylinder (75) is fixedly installed at the bottom center of the mixing cylinder (6); The discharge bend (76) is fixedly installed at the bottom end of the discharge cylinder (75); The discharge valve (77) is screwed to the front side of the discharge bend (76); The rotating shaft (78) is rotatably connected to the outer wall of the discharge cylinder (75); Cam (79), one end of the rotating shaft (78) extends into the inner cavity of the discharge cylinder (75) and is fixedly provided with cam (79); The top plate (710) is inserted into the inner cavity of the discharge cylinder (75), and the top plate (710) contacts the top end of the cam (79); A cover (711) is fixedly installed at the top of the top plate (710), and a through hole (714) is provided at the bottom end of the discharge cylinder (75), and the cover (711) is adapted to be inserted into the inner cavity of the through hole (714). Limiting rods (712) are fixedly provided on both the left and right sides of the bottom end of the mixing cylinder (6), and the limiting rods (712) are located inside the discharge cylinder (75). The top plate (710) is adapted to be connected with the limiting rods (712). A sealing gasket (713) is fixedly installed at the bottom end of the stirring cylinder (6) and located between the stirring cylinder (6) and the top plate (710). The sealing gasket (713) is sleeved with the limiting rod (712).

8. The apparatus for preparing lead-free paste for QFN chips according to claim 7, characterized in that: The far hub end of the cam (79) contacts the bottom end of the top plate (710).

9. The apparatus for preparing lead-free paste for QFN chips according to claim 7, characterized in that: The cap (711) and the bottom of the inner cavity of the stirring cylinder (6) are located on the same plane.

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