PCB board fixing device of a tin paste printing machine

Abstract

The application discloses a PCB fixing device of a tin paste printing machine, and relates to the technical field of tin paste printing. The application ingeniously utilizes the characteristics of elastic self-adaptive adjustment of the moving column and gas and liquid follow-up compensation, automatically adjusts the support height of each suction cup and the moving column according to the warping degree of the processing plate, makes the processing plate be uniformly adsorbed and flattened, effectively restrains the rebound when the doctor blade is pressed down, avoids tin tips and printing size fluctuation caused by the floating of the plate surface, and prevents tin paste from penetrating into the solder resist layer to cause short circuit or tin bead residue.

Description

Technical Field

[0001] This invention relates to the field of solder paste printing technology, specifically to a PCB board fixing device for a solder paste printing machine. Background Technology

[0002] In the SMT production process, solder paste printing is the first and most critical step, and its quality directly affects the soldering effect of subsequent components. In order to ensure printing accuracy, PCB board fixing devices have emerged. Their core function is to resist the pressure of the squeegee during the printing process and to firmly clamp the PCB board during the printing process, thereby ensuring the accuracy and consistency of solder paste printing.

[0003] When a PCB board enters the solder paste printing machine, although the ideal state is absolute flatness, slight warping is often allowed in actual production. This is because the board is made of various materials such as copper foil and resin, and different materials have different degrees of thermal expansion and contraction. In addition, residual internal stress is inevitable during the manufacturing process, so it is difficult to achieve the ideal state of absolute flatness and zero warping.

[0004] Solder paste printing is a critical step in the SMT process, and most soldering defects originate from it. However, if the PCB board is not flat, and slight warping occurs under certain critical conditions, it can cause the following problems: 1. If the board is bent downwards (concave), the middle area will be suspended due to insufficient support during board suction. When the squeegee presses down during printing, the middle of the board will be pressed down like a springboard. After being released, it will quickly rebound. This slight floating will cause the solder paste to be stretched and form "solder spikes" during demolding. It will also easily cause unstable printing dimensions and affect repeatability accuracy. If the board is bent upwards (arched), the edge of the board cannot fit tightly with the stencil, which will create a small gap. This will also affect the uniformity of pressure distribution when the squeegee moves down. During printing, the solder paste will seep into the PCB solder mask layer from the gap, causing residual solder beads or short circuits on the board surface.

[0005] 2. During the stripping process of stencil detachment, uneven board surfaces can cause the stencil opening walls to pull solder paste, resulting in insufficient solder paste (insufficient solder) or burrs (sharpening) on ​​the edges. Although high-precision printers have optical positioning capabilities, they can still cause local pads to shift relative to the stencil openings, leading to printing misalignment and consequently causing mounting defects such as tombstoning or cold solder joints.

[0006] To address the aforementioned issues, there is an urgent need for innovative design of the PCB board fixing device in the existing solder paste printing machine. Summary of the Invention

[0007] The present invention addresses the problem of overly simplistic solutions in existing technologies by providing a significantly different solution. Specifically, the present invention aims to provide a PCB board fixing device for a solder paste printer, thereby solving the problems mentioned in the background art, such as solder spikes caused by slight warping of the processed board, which affect dimensional stability, lead to poor edge adhesion, increase solder paste penetration into the solder resist layer, resulting in solder balls or short circuits, and cause uneven board surface, which leads to the problem of solder paste being pulled during demolding.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a PCB board fixing device for a solder paste printing machine, comprising a printing machine body, side clamping assemblies symmetrically arranged in the printing machine body, and a processing board clamped at the bottom end of the side clamping assemblies, and further comprising: A liquid storage box is set in the middle of the side clamp assembly to store liquid; A fixed platform attached to the top of the liquid storage box for support; The gas storage pipe and liquid storage pipe are symmetrically fixed at the upper and lower ends of the fixed platform; Equally spaced movable columns are inserted into a fixed platform, adaptively adjusting their support height based on the warping of the processing plate; A push rod fixed to the bottom of the movable column, moving synchronously with it and changing the amount of liquid inside the storage box; Liquid storage boxes and square boxes are distributed on both sides and top of the liquid storage box to temporarily store liquid, respectively. Adjustment plates symmetrically distributed in the liquid storage box to push the push rod to reset and correct warping; An adjusting component is fixed to the bottom of the side clamping assembly and moves adaptively according to the clamping condition of the processing plate. The adjusting component includes a top plate fixed to the bottom of the side clamping assembly, a clamping plate movably inserted into the bottom of the top plate, and steel balls that are rolled in the top plate.

[0009] Preferably, the printing press body is provided with a support platform located below the side clamping assembly, and a liquid storage box is fixed to the top of the support platform; A vacuum generator is installed on one side of the liquid storage box and the fixed platform, and the two sides of the vacuum generator are respectively connected to a first connecting pipe and a second connecting pipe.

[0010] Preferably, a limiting block is symmetrically fixed at the middle position of the inner wall of the liquid storage box, and the limiting block is in contact with the adjusting plate. The height of the limiting block is adapted to the bottom end of the push rod. The liquid storage box and the adjusting plate are respectively equipped with sealing rings at the movable connection points with the push rod.

[0011] Preferably, a movable plate is movably inserted into the inner wall of the liquid storage box, and the movable plate is elastically connected to the inner wall of the liquid storage box. The liquid storage box and the liquid storage box are connected and are equipped with an electromagnetic reversing valve. The liquid storage box, liquid reservoir, and square box are each filled with liquid.

[0012] Preferably, the gas storage pipes are fixed at equal intervals at the top of the fixed platform, and one end of each gas storage pipe is connected to a second connecting pipe. The inner wall of the gas storage pipe is movably inserted with a push plate, and the push plate is fixed on the surface of the moving column. A first spring is fixed to the top of the gas storage pipe, and the other side of the first spring is fixed to the surface of the moving column.

[0013] Preferably, the liquid storage tubes are fixed at equal intervals at the bottom of the fixed platform, and one end of the liquid storage tube is connected to the square box; A push rod is movably inserted into the liquid storage tube, and a push plate is fixedly sleeved on the surface of the push rod; The bottom end of the liquid storage tube is fixed with a first spring, and the other side of the first spring is fixed to the surface of the push rod.

[0014] Preferably, the top end of the movable column is connected to the suction cup, and one side of the movable column is connected to the first connecting tube; The movable column is simultaneously and movably connected to the gas storage pipe and the liquid storage pipe, and the push plate surface on the inner wall of the gas storage pipe and the liquid storage pipe is fixedly fitted with a sealing ring.

[0015] Preferably, the push rod is movably inserted into the top of the liquid storage box; The surface of the push rod is in contact with the surface of the adjusting plate, and the push rod is movably inserted into one of the adjusting plates.

[0016] Preferably, a clamping plate for limiting the processing plate is movably provided at the bottom end of the top plate, and the clamping plate is L-shaped, with a rubber pad fixedly laid on the side of the clamping plate that contacts the processing plate; The inner wall of the top plate is provided with U-shaped grooves at equal intervals, and steel balls are rolled in the U-shaped grooves.

[0017] Preferably, the steel balls are provided in several groups, with the surface of the steel balls at the edge contacting one end of the clamping plate, the top end of the clamping plate being located in a U-shaped groove, and the top end of the clamping plate being smaller than the diameter of the steel balls; A second spring is fixed to one side of the U-shaped groove, and the other side of the second spring is in contact with the surface of the steel ball.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention cleverly utilizes the elastic adaptive adjustment of the moving column and the characteristics of gas and liquid follow-up compensation. It automatically adjusts the support height of each suction cup and moving column according to the warp of the processing board, so that the processing board is evenly adsorbed and flattened. When the processing board bends downward into a concave shape, the moving column and push rod at the corresponding position are pushed down more, and the liquid in the reservoir flows into the square box to compensate for the displacement, providing stable support for the reference height area, effectively suppressing the rebound when the squeegee is pressed down, and avoiding solder spikes and printing size fluctuations caused by board surface floating. When the processing board bends upward into an arch shape, the position of the suction cup and push rod at the corresponding position is raised, and the liquid compensates for its height. The board edge is tightly attached to the stencil, so that the pressure is evenly distributed when the squeegee moves down, eliminating local gaps and preventing solder paste from seeping into the solder resist layer, causing short circuits or solder ball residue.

[0019] 2. This invention cleverly utilizes the liquid buffer reset feature. After the liquid in the reservoir compensates for the height difference, the reset and correction ensures that the board surface is flat and uniform. A stable and uniform board surface helps the stencil to detach smoothly, reduces the risk of solder paste being pulled, ensures consistent solder paste quantity, and allows for uniform peeling of the solder paste from the stencil opening wall, reducing defects such as insufficient solder and solder spikes caused by pulling. At the same time, when the vacuum adsorption reaches the threshold, the liquid reset causes multiple sets of moving columns and push rods to reset smoothly. Combined with the slight displacement of the adjustment components, local stress is eliminated, board surface deformation is reduced, and the precise alignment of the solder pads with the stencil opening is achieved, effectively reducing mounting defects such as printing misalignment, tombstoning, and cold solder joints. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the first three-dimensional structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the second three-dimensional structure of the present invention.

[0022] Figure 3 This is a schematic diagram of the third three-dimensional structure of the present invention.

[0023] Figure 4 This is a three-dimensional structural diagram of the liquid storage box and fixing platform of the present invention.

[0024] Figure 5 This is a schematic diagram of the planar structure of the gas storage pipe and liquid storage pipe of the present invention.

[0025] Figure 6 This is a three-dimensional structural diagram of the movable column and push rod of the present invention.

[0026] Figure 7 This is a three-dimensional cross-sectional structural diagram of the gas storage pipe and liquid storage pipe of the present invention.

[0027] Figure 8 This is a three-dimensional structural diagram of the liquid storage box and the square box of the present invention.

[0028] Figure 9This is a three-dimensional cross-sectional structural diagram of the liquid storage box of the present invention.

[0029] Figure 10 This is a schematic diagram of the horizontal structure of the push rod and adjusting plate of the present invention.

[0030] Figure 11 This is a three-dimensional structural diagram of the top plate and clamping plate of the present invention.

[0031] Figure 12 This is a three-dimensional structural diagram of the steel ball and the second spring of the present invention.

[0032] Figure 13 This is a schematic diagram illustrating the usage state of the present invention.

[0033] In the diagram: 1. Printing machine body; 2. Side clamping assembly; 3. Processing plate; 4. Liquid storage box; 5. Fixed platform; 6. Liquid storage box; 7. Gas storage pipe; 8. Suction cup; 9. Liquid storage pipe; 10. First connecting pipe; 11. Second connecting pipe; 12. Square box; 13. First spring; 14. Moving column; 15. Push rod; 16. Push plate; 17. Top plate; 18. Clamping plate; 19. Steel ball; 20. Second spring; 21. Adjusting plate; 22. Moving plate. Detailed Implementation

[0034] 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.

[0035] Please see Figures 1 to 13 The present invention provides a technical solution: a PCB board fixing device for a solder paste printing machine, comprising a printing machine body 1, side clamping assemblies 2 symmetrically arranged in the printing machine body 1, and a processing board 3 clamped at the bottom end of the side clamping assemblies 2, and further comprising: A liquid storage box 4 is set in the middle of the side clamp assembly 2 to store liquid; A fixed platform 5 is fixed to the top of the liquid storage box 4 for support; The gas storage pipe 7 and liquid storage pipe 9 are symmetrically fixed at the upper and lower ends of the fixed platform 5; Equally spaced movable columns 14 are inserted into the fixed platform 5 and adaptively adjust their support height based on the warping of the processing plate 3; A push rod 15 fixed to the bottom of the movable column 14 moves synchronously with it and changes the amount of liquid inside the liquid storage box 4; Liquid storage boxes 6 and square boxes 12 are distributed on both sides and top of liquid storage box 4 to temporarily store liquid, respectively; Adjustment plates 21, symmetrically distributed in the liquid storage box 4, push the push rod 15 to reset and correct the warping; An adjustment component is fixed to the bottom end of the side clamping assembly 2 and moves adaptively according to the clamping condition of the processing plate 3. The adjustment component includes a top plate 17 fixed to the bottom end of the side clamping assembly 2, a clamping plate 18 movably inserted into the bottom end of the top plate 17, and steel balls 19 rolling in the top plate 17.

[0036] Additionally, it should be noted that the side clamp assembly 2 contains a motor-driven conveyor belt. The processing plate 3 is delivered from the previous stage equipment and falls directly onto the conveyor belt. Through the friction transmission of the belt, the processing plate 3 is smoothly delivered into the working position inside the printing machine, located above the support platform. This is existing technology and will not be elaborated further here.

[0037] In practice, a support platform is provided on the main body 1 of the printing press below the side clamping assembly 2, and a liquid storage box 4 is fixed on the top of the support platform; A vacuum generator is installed on one side of both the liquid storage box 4 and the fixed platform 5, and the two sides of the vacuum generator are respectively connected to the first connecting pipe 10 and the second connecting pipe 11.

[0038] Additionally, it should be noted that the vacuum generator is equipped with two sets of vacuum valves and pressure relief valves. The first connecting pipe 10 and the second connecting pipe 11 are respectively connected to the vacuum valve and the pressure relief valve. The multiple suction cups 8 and the gas storage pipe 7 are connected through the first connecting pipe 10 and the second connecting pipe 11.

[0039] In specific implementation, a limiting block is symmetrically fixed at the middle position of the inner wall of the liquid storage box 4, and the limiting block is in contact with the adjusting plate 21. The height of the limiting block is matched with the bottom end of the push rod 15. Additionally, it should be noted that the main body of the processing plate 3 is flat, with only a small portion warped. Most of the suction cups 8, moving posts 14, and push rods 15 are at the reference height. Figure 13 As shown, when the reference height is mostly reached, such as at point B, the push rod 15 and the limiting block are at the same height. When the processing plate 3 is warped, as shown at points A and C, the push rod 15 is located above and below the limiting block. After the height is corrected, the upper and lower sets of adjusting plates 21 are pushed towards the middle at the same time. When they are pushed to the height of the limiting block, it is exactly the reference height. The limiting block is used as the standard for correction, thereby helping to overcome most of the warping and making the processing plate 3 change from "bent" to "straight". This improves the accurate alignment with the opening of the steel mesh, thereby reducing tombstoning and incomplete welding caused by misalignment.

[0040] Sealing rings are provided at the movable connection points between the liquid storage box 4 and the adjusting plate 21 and the push rod 15.

[0041] In specific implementation, a movable plate 22 is movably inserted into the inner wall of the liquid storage box 6, and the movable plate 22 is elastically connected to the inner wall of the liquid storage box 6. The liquid storage box 6 and the liquid storage box 4 are connected and equipped with an electromagnetic reversing valve; the liquid storage box 6, the liquid storage box 4 and the square box 12 are respectively filled with liquid.

[0042] Additionally, it should be noted that the electromagnetic reversing valve is activated when the vacuum level of all suction cups 8 reaches the set threshold. A pressure switch and a relay are provided between the two. When the vacuum valve is closed, the magnetic switch installed on it detects the position signal and conducts, sending an electrical signal to the relay to activate the electromagnetic reversing valve or the pressure relief valve.

[0043] In practice, the gas storage pipes 7 are fixed at equal intervals on the top of the fixed platform 5, and one end of the gas storage pipes 7 is connected to the second connecting pipe 11. A push plate 16 is movably inserted into the inner wall of the gas storage pipe 7, and the push plate 16 is fixed to the surface of the moving column 14. A first spring 13 is fixed to the top of the gas storage pipe 7, and the other side of the first spring 13 is fixed to the surface of the moving column 14.

[0044] In practice, the liquid storage tubes 9 are fixed at equal intervals at the bottom of the fixed platform 5, and one end of the liquid storage tubes 9 is connected to the square box 12. A push rod 15 is movably inserted into the liquid storage tube 9, and a push plate 16 is fixedly sleeved on the surface of the push rod 15; Additionally, it should be noted that the push plate 16, which is fitted onto the surfaces of the moving column 14 and the push rod 15, squeezes or increases the space for the gas and liquid in the gas storage pipe 7 and the liquid storage pipe 9, respectively, to help reset and correct the situation. The gas and liquid cause the moving column 14 and the push rod 15 to automatically descend and fill the displacement, providing rigid support for the suspended area.

[0045] A first spring 13 is fixed to the bottom end of the liquid storage tube 9, and the other side of the first spring 13 is fixed to the surface of the push rod 15.

[0046] In addition, it should be noted that the first spring 13 is provided in multiple sets, which are respectively sleeved on the surface of the moving column 14 and the push rod 15, so that it can be displaced according to the degree of warping of the processing plate 3, and can support and absorb the downward concave and upward arched positions in the warped area.

[0047] In practice, the top of the movable column 14 is connected to the suction cup 8, and one side of the movable column 14 is connected to the first connecting pipe 10. The movable column 14 is simultaneously connected to the gas storage pipe 7 and the liquid storage pipe 9. The push plate 16 on the inner wall of the gas storage pipe 7 and the liquid storage pipe 9 is fixedly fitted with a sealing ring.

[0048] In specific implementation, the push rod 15 is movably inserted into the top of the liquid storage box 4; the surface of the push rod 15 is in contact with the surface of the adjustment plate 21, and the push rod 15 is movably inserted into one of the adjustment plates 21.

[0049] Additionally, it should be noted that after the multiple sets of suction cups 8 and moving columns 14 move according to the degree of warping of the processing board 3, when the multiple sets of moving columns 14 and suction cups 8 are subjected to resistance or thrust, the push rod 15 located at the deepest recess or the highest protrusion simultaneously drives the adjusting plate 21 to move to both sides, pushing the adjusting plate 21 to a lower position, squeezing the liquid in the liquid storage box 4 into the liquid storage box 4. The lowering of the adjusting plate 21 causes the liquid in the liquid storage box 4 to flow to the liquid storage box 6. The height of the adjusting plate 21 represents the degree of warping of the processing board 3 at the highest and lowest points. The position outside the reference point to the lowest or highest point is at an intermediate level. Finally, the adjusting plate 21 at the lowest and highest points will push to reset and correct, so that the processing board 3 is kept on a flat plane during the subsequent printing process. When the stencil is lifted, the force of the solder paste separating from the hole wall is uniform and synchronous, improving the printing quality.

[0050] In specific implementation, a clamping plate 18 for limiting the processing plate 3 is movably provided at the bottom end of the top plate 17, and the clamping plate 18 is L-shaped, with a rubber pad fixedly laid on the side of the clamping plate 18 that contacts the processing plate 3. In addition, it should be noted that the rubber material has good friction and a certain degree of elasticity. It is necessary to prevent slippage and avoid damaging the processing plate 3, so as to protect the processing plate 3 and reduce its displacement.

[0051] The inner wall of the top plate 17 is provided with U-shaped grooves at equal intervals, and steel balls 19 are rolled in the U-shaped grooves.

[0052] In specific implementation, there are several sets of steel balls 19. The surface of the steel ball 19 located at the edge is in contact with one end of the clamping plate 18. The top end of the clamping plate 18 is located in the U-shaped groove, and the top end of the clamping plate 18 is smaller than the diameter of the steel ball 19. A second spring 20 is fixed on one side of the U-shaped groove, and the other side of the second spring 20 is in contact with the surface of the steel ball 19.

[0053] Additionally, it should be noted that after the unevenness at the warped part of the processing plate 3 becomes flat, the length of the processing plate 3 changes slightly (the geometric length increases after bending to straightening). The second spring 20 extends and retracts with the change in the length of the processing plate 3, and the clamping plate 18 moves with the change in the length of the processing plate 3. The second spring 20 and the clamping plate 18 simultaneously push the steel ball 19 in the top plate 17 to roll, and the clamping adjustment is adaptive according to the length of the processing plate 3. The slight displacement driven by the left and right clamping devices can assist the processing plate 3 in making fine adjustments in the plane, helping its stress to be released more naturally and "reset".

[0054] Working principle: When using the PCB board fixing device of the solder paste printing machine, the processing board 3 is first fed in and positioned by the conveyor belt, and then the support platform is pushed up. Multiple sets of suction cups 8 first lift the processing board 3 away from the conveyor belt and move it closer to the clamping plate 18. At this time, the side of the processing board 3 contacts the inner wall of the clamping plate 18. The clamping plate 18 moves in the top plate 17 according to the length of the processing board 3. The second spring 20 pushes the steel ball 19 to adaptively clamp the processing board 3.

[0055] When the processing plate 3 is limited by the clamping plate 18 on its side, as the support platform continues to rise, the internal nozzles and vacuum valves of the vacuum generator continuously evacuate the suction cup 8 through the first connecting pipe 10 until the suction cup 8 adheres tightly to the processing plate 3. Multiple sets of moving columns 14 and the suction cup 8 are then pushed upwards together. At this point, when the suction cup 8 is located in the downward-curving recess of the processing plate 3, as... Figure 13 As shown at point C, multiple sets of moving columns 14 and suction cups 8 move downwards simultaneously to different heights after encountering resistance. As the moving columns 14 move downwards, they drive the push rods 15 and push plates 16 to move downwards simultaneously. The push plates 16 squeeze the liquid in the storage tube 9 downwards into the square box 12. The push rods 15 push the adjusting plate 21 at the bottom downwards to the bottom. The push rods 15 located at the deepest part of the recess push the adjusting plate 21 to the maximum position. The downward movement of the adjusting plate 21 causes the liquid in the storage box 4 to flow into the liquid storage box 6. The liquid pushes into the liquid storage box 6 and pushes the moving plate 22 to move.

[0056] When the support platform is pushed upwards until most of the suction cups 8 are adsorbed with the processing plate 3, it stops pushing upwards. At this point, most of the moving columns 14 and push rods 15 are at the reference height, and push rod 15 is located at the horizontal reference position in the liquid storage box 4. Figure 13 As shown at point B, at the same time, the suction cup 8 located below the processing plate 3 at the upwardly curved arch is not in full contact with it, as... Figure 13 As shown at point A, at this time, the vacuum generator's breaking valve delivers air to the gas storage pipe 7 through the second connecting pipe 11. After the air enters, it pushes the push plate 16 and the moving column 14 upward until the suction cup 8 and the processing plate 3 are fully adsorbed. Then, the pressure relief valve is closed to stop the input. Multiple sets of moving columns 14 move upward to different heights according to the protrusion of the processing plate 3. As multiple sets of moving columns 14 move upward, the liquid storage pipe 9 is in a negative pressure state. The liquid in the square box 12 enters the liquid storage pipe 9. At the same time, the push rod 15 located at the high point of the curved arch pushes the adjusting plate 21 upward to the bottom, so that the internal liquid flows into the liquid storage box 6.

[0057] After multiple suction cups 8 have fully adhered to the processing plate 3, and the vacuum degree of all suction cups 8 reaches the set threshold, the vacuum valve at the first connecting pipe 10 is closed. At this time, the electromagnetic reversing valve is activated, and the liquid in the storage box 6 is squeezed back into the storage box 4 by the moving plate 22. The liquid generates force to push the symmetrical adjusting plate 21 to reset. The adjusting plate 21 moves towards the center at the same time, driving multiple sets of push rods 15 of different heights to move until they reach the reference height. Thus, the push rods 15 at the lower position push the moving column 14 and the suction cups 8 upwards, and the firmly adhered suction cups 8 move towards the processing plate 3. At the concave part of the upper processing plate 3, the push rod 15 at the higher position drives the moving column 14 and the suction cup 8 to move downwards. The suction cup 8 pulls down the convex part of the processing plate 3 to correct the warping of the processing plate 3. After correction, the multiple sets of moving columns 14 and push rods 15 are at the same height. At this time, the space in the liquid storage tube 9 at the warped part changes. The liquid in the square box 12 is squeezed by the push plate 16 or reset by negative pressure. The liquid in the square box 12 is reset. After the solenoid valve is started, the rupture valve at the second connecting pipe 11 opens at the same time to draw away the air inside the gas storage tube 7.

[0058] After the positions of multiple processing plates 3 are corrected, the unevenness at their warped points becomes flat, and the length of the processing plate 3 changes slightly. The second spring 20 extends and retracts with the change in the length of the processing plate 3, and the clamping plate 18 moves with the change in the length of the processing plate 3. The second spring 20 and the clamping plate 18 simultaneously push the steel ball 19 in the top plate 17 to roll, and the clamping adjustment is adaptive according to the length of the processing plate 3. Finally, the processing plate 3 is fixed and printed. After printing, the support platform moves down, and the processing plate 3 falls from the clamping plate 18 onto the conveyor belt. After the suction cup 8 is depressurized, it no longer supports the processing plate 3, and the processing plate 3 is conveyed to the next step.

[0059] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A PCB board fixing device for a solder paste printing machine, comprising a printing machine body (1), side clamping assemblies (2) symmetrically arranged in the printing machine body (1), and a processing board (3) clamping the bottom end of the side clamping assemblies (2), characterized in that, Also includes: A liquid storage box (4) is set in the middle of the side clamp assembly (2) to store liquid; A fixed platform (5) is fixed to the top of the liquid storage box (4) for support; Gas storage pipe (7) and liquid storage pipe (9) are symmetrically fixed at the upper and lower ends of the fixed platform (5). Equally spaced movable columns (14) are inserted into the fixed platform (5) and the height of the support is adaptively adjusted based on the warping of the processing plate (3). A push rod (15) is fixed at the bottom of the movable column (14) and moves synchronously with it to change the amount of liquid inside the liquid storage box (4). Liquid storage boxes (6) and square boxes (12) are distributed on both sides and top of the liquid storage box (4) to temporarily store liquids respectively. The adjustment plate (21) is symmetrically distributed in the liquid storage box (4) to push the push rod (15) to reset and correct the warping. An adjustment assembly is fixed at the bottom of the side clamping assembly (2) and moves adaptively according to the clamping condition of the processing plate (3). The adjustment assembly includes a top plate (17) fixed at the bottom of the side clamping assembly (2), a clamping plate (18) movably inserted at the bottom of the top plate (17), and steel balls (19) rolling in the top plate (17).

2. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The printing press body (1) is provided with a support platform located below the side clamp assembly (2), and a liquid storage box (4) is fixed at the top of the support platform. A vacuum generator is installed on one side of the liquid storage box (4) and the fixed platform (5), and the two sides of the vacuum generator are respectively connected to the first connecting pipe (10) and the second connecting pipe (11).

3. The PCB board fixing device for a solder paste printing machine according to claim 2, characterized in that: A limiting block is symmetrically fixed at the middle position of the inner wall of the liquid storage box (4), and the limiting block is in contact with the adjusting plate (21). The height of the limiting block is matched with the bottom end of the push rod (15). The liquid storage box (4) and the adjusting plate (21) are respectively provided with sealing rings at the movable connection points with the push rod (15).

4. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The inner wall of the liquid storage box (6) is movably inserted with a movable plate (22), and the movable plate (22) is elastically connected to the inner wall of the liquid storage box (6). The liquid storage box (6) is connected to the liquid storage box (4) and is equipped with an electromagnetic reversing valve; The liquid storage box (6), the liquid storage box (4), and the square box (12) are respectively filled with liquid.

5. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The gas storage pipes (7) are fixed at equal intervals at the top of the fixed platform (5), and one end of the gas storage pipes (7) is connected to a second connecting pipe (11). The inner wall of the gas storage pipe (7) is movably inserted with a push plate (16), and the push plate (16) is fixed on the surface of the moving column (14). The top end of the gas storage pipe (7) is fixed with a first spring (13), and the other side of the first spring (13) is fixed to the surface of the moving column (14).

6. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The liquid storage tubes (9) are fixed at equal intervals at the bottom of the fixed platform (5), and one end of the liquid storage tubes (9) is connected to the square box (12). A push rod (15) is movably inserted into the liquid storage tube (9), and a push plate (16) is fixedly sleeved on the surface of the push rod (15). The bottom end of the liquid storage tube (9) is fixed with a first spring (13), and the other side of the first spring (13) is fixed to the surface of the push rod (15).

7. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The top of the movable column (14) is connected to the suction cup (8), and one side of the movable column (14) is connected to the first connecting pipe (10). The movable column (14) is simultaneously connected to the gas storage pipe (7) and the liquid storage pipe (9) by movable insertion. The push plate (16) on the inner wall of the gas storage pipe (7) and the liquid storage pipe (9) are both fixedly fitted with sealing rings.

8. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The push rod (15) is movably inserted into the top of the liquid storage box (4); The surface of the push rod (15) is in contact with the surface of the adjustment plate (21), and the push rod (15) is movably inserted into one of the adjustment plates (21).

9. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The bottom end of the top plate (17) is movably provided with a clamping plate (18) for limiting the processing plate (3), and the clamping plate (18) is L-shaped. A rubber pad is fixedly laid on the side of the clamping plate (18) that contacts the processing plate (3). The inner wall of the top plate (17) is provided with U-shaped grooves at equal intervals, and steel balls (19) are rolled in the U-shaped grooves.

10. The PCB board fixing device for a solder paste printing machine according to claim 1, characterized in that: The steel ball (19) is provided in several groups. The surface of the steel ball (19) located at the edge is in contact with one end of the clamping plate (18). The top end of the clamping plate (18) is located in the U-shaped groove. The top end of the clamping plate (18) is smaller than the diameter of the steel ball (19). A second spring (20) is fixed on one side of the U-shaped groove, and the other side of the second spring (20) is in contact with the surface of the steel ball (19).

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