Solder paste dispensing device for varistor production line

Abstract

The invention discloses a solder paste dispensing device for a piezoresistor production line, which relates to the technical field of solder paste dispensing and comprises an extrusion pipe, an inflation tank, a mounting rack, a vent, a piston, a gas delivery pipe and an annular gas delivery pipe. In the solder paste dispensing operation, the sealing shell is combined to weigh solder paste entering the metering opening, the sealing shell is jacked open by the continuously injected solder paste after the space is full, the metering opening is plugged through cooperation of the connecting pull rope and the sealing plate, the solder paste is pushed to be discharged through air by means of the air inlet and the plugging block, the single-time dispensing amount is limited through the physical volume, the influence of viscosity change is avoided, and the dispensing precision is improved. During spot coating, air flow drives a turbine and a stirring frame to stir and mix the solder paste at the blocking position, a rotating rod rotates to drive the stirring frame to shake in a reciprocating mode, the solder paste is uniform in component and appropriate in viscosity, the spot coating effect of each time is ensured, and when residual solder paste is cleaned, an annular air conveying pipe blows air for cleaning, and a shielding shell protects and shields; when the sealing shell is opened, the lantern ring drives the shielding shell to be separated, and production and machining are not affected.

Description

Technical Field

[0001] The invention relates to the technical field of solder paste dispensing, in particular to a solder paste dispensing device for a varistor production line. Background Art

[0002] Varistor is the abbreviation of voltage-sensitive resistor, which is a nonlinear resistance element. The resistance of a varistor is related to the voltage applied at both ends. When the voltage applied to the varistor is within its nominal value, the resistance of the resistor is infinite and almost no current passes through. When the voltage across the varistor is slightly greater than the nominal voltage, the varistor quickly breaks down and conducts, and its resistance drops quickly, making the resistor in the on state. It is an ideal protection element and is widely used in home appliances and other electronic products. It is often used to form overvoltage protection circuits, noise elimination circuits, spark elimination circuits, lightning protection circuits, surge voltage absorption circuits and protect semiconductor components.

[0003] For example, Chinese patent CN202411311351.4 discloses a solder paste dispensing device for a varistor production line, which can control the pressure in the air tank to control the pushing speed and force of the piston, thereby achieving control of the extrusion amount of hot melt adhesive and solder paste.

[0004] However, the existing solder paste dispensing device still has the following problems during implementation: For example, the existing solder paste dispensing device uses air pressure to push the piston to extrude the solder paste. The actual pushing pressure is not only greatly affected by the air pressure fluctuation, but also the extrusion amount is limited by the physical properties of the solder paste (viscosity, particle size, bubble content). This is because the solder paste is a non-Newtonian fluid with thixotropy. The ambient temperature, the stability of the solder paste, and the particle size of the solder particles will affect its viscosity. Therefore, after the dispensing is completed, the viscosity of the solder paste will change when the above-mentioned patented technology is used to replace and install a new PCB, which will directly affect the repeatability of the extrusion amount, resulting in the inability to accurately control the solder paste dispensing content. At the same time, when the residual solder paste is subsequently removed without considering the protection aspect, it is easy to cause the blown solder paste particles to splash to the area after dispensing below, contaminating the workpiece surface and affecting the production of varistor components. Summary of the invention

[0005] The object of the present invention is to provide a solder paste dispensing device for a varistor production line to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above-mentioned object, the present invention provides a solder paste dispensing device for a varistor production line, comprising an extrusion tube, an air filling tank, a mounting frame, an air vent, a piston, a gas delivery pipe, an annular gas delivery pipe, a workbench, a transverse moving component, and a longitudinal moving component, wherein the top of the extrusion tube is symmetrically provided with transmission holes, and the bottom of the air filling tank is symmetrically provided with through holes corresponding to the transmission holes; A quantitative delivery component is arranged inside the extrusion tube to adopt physical volume to limit the single application amount during the push of solder paste dot application, so as to avoid the influence of viscosity change on the extrusion amount; An intermittent stirring component is arranged inside the extrusion tube to intermittently stir and mix the solder paste sufficiently during the push of solder paste dot application, and control the viscosity of the solder paste within a suitable range; A blowing protection component is arranged on the outer wall of the extrusion tube to protect and shield the cleaning position during the blowing of residual solder paste, and avoid the solder paste particles splashing everywhere and polluting the surface of the workpiece.

[0007] Preferably, the quantitative delivery component includes a fixed ring, and the outer wall of the fixed ring is fixedly connected to the inner wall of the extrusion tube. A metering port is penetrated and opened at the center of the end face of the fixed ring. The bottom of the extrusion tube is fixedly connected with a dot application head, and two support blocks I are symmetrically fixedly connected to the bottom of the dot application head. A shaft rod is rotatably connected inside the two support blocks I. Two support blocks II are symmetrically fixedly connected to the outer walls of the two shaft rods, and the bottom of the support block II is fixedly connected with a sealing shell. Torsion springs are symmetrically arranged on the outer walls of the two shaft rods. One side walls of the two support blocks II close to each other are fixedly connected to the ends of the two torsion springs away from each other. One ends of the two torsion springs close to each other are fixedly connected to the outer walls on both sides of the support block I. Connecting pull ropes are fixedly connected to the outer walls on both sides of the two sealing shells away from each other.

[0008] Preferably, through grooves are symmetrically penetrated and opened on the inner wall of the metering port, and sealing plates are slidably connected to the inner walls of the through grooves in a fitting manner. Grooves I are symmetrically opened on the inner wall of the extrusion tube corresponding to the through grooves, and a first spring is fixedly connected to the inner wall of the groove I. One ends of the two first springs close to each other are respectively fixedly connected to the outer walls on both sides of the two sealing plates away from each other. The other ends of the two connecting pull ropes respectively pass through the inside of the extrusion tube and are fixedly connected to the outer walls on both sides of the two sealing plates away from each other. Air inlet holes are symmetrically opened on the upper and lower end faces of the fixed ring. Plug blocks are slidably connected to the inner walls of the four air inlet holes in a fitting manner.

[0009] Preferably, grooves II are correspondingly opened on the inner walls of the four air inlet holes. Connecting frames are symmetrically fixedly connected to the upper surfaces of the four plug blocks corresponding to the grooves II. A second spring is fixedly connected to the inner surface of the top side of the connecting frame, and the other end of the second spring is fixedly connected to the inner wall of the groove II. The plug block and the connecting frame and the second spring form a telescopic structure. A cover plate is fixedly connected to the upper surface of the fixed ring corresponding to the air inlet hole, and a communicating pipe is fixedly connected to the top of the cover plate. The other end of the communicating pipe is fixedly connected to the inner wall of the extrusion tube corresponding to the transmission hole.

[0010] Preferably, the intermittent stirring component includes a rotating rod. An installation groove is formed in the inner wall of the extrusion tube corresponding to the penetration of the rotating rod, and the outer wall of the rotating rod is arranged on the inner wall of the installation groove. A turbine is fixedly connected to one end of the rotating rod corresponding to the transmission hole, and a stirring frame is fixedly connected to the other end of the rotating rod corresponding to the extrusion tube. A guiding groove is formed in the outer wall of the rotating rod, and a guiding block is fixedly connected to the inner wall of the installation groove corresponding to the guiding groove. The bottom of the guiding block is slidably attached to the inner wall of the guiding groove.

[0011] Preferably, a housing is rotatably attached to the outer wall of the rotating rod, and the outer wall of the housing is slidably connected to the inner wall of the installation groove. A sliding groove is formed in the outer wall of the housing corresponding to the guiding block, and the outer wall of the guiding block is slidably attached to the inner wall of the sliding groove.

[0012] Preferably, the blowing and protecting component includes a shielding shell. A connecting rod is hinged to one side of the two shielding shells close to each other. One ends of the two connecting rods close to each other are fixedly connected to the bottom outer wall of the extrusion tube. The outer wall of the connecting pull rope is slidably connected inside the shielding shell. Collars are fixedly connected to the outer walls of the two connecting pull ropes, and the outer walls of the collars are attached to and close to the inner wall of the shielding shell.

[0013] Preferably, the top end of the extrusion tube is threadedly connected to the bottom of the inflatable tank. The outer wall of the inflatable tank is rotatably installed inside the installation frame. The air vent is opened at the bottom of the inflatable tank. The piston is slidably installed inside the extrusion tube. One end of the gas delivery pipe is fixedly installed on one outer wall of the inflatable tank. The annular gas delivery pipe is installed corresponding to the sealing shell on the outer wall of the dotting head. The transverse movement component is installed at the rear side of the workbench. The longitudinal movement component is installed inside the transverse movement component. The longitudinal movement component cooperates with the transverse movement component. The extrusion tube is installed inside the longitudinal movement component.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. When pushing the solder paste for dotting, the solder paste content entering from the metering port can be weighed through the combined sealing shell. When the space between the fixed ring and the sealing shell is filled with solder paste, the solder paste continuously injected at this time will push open the sealing shell. Thus, the metering port can be blocked through the cooperation of the connecting pull rope and the sealing plate to complete the metering of one dotting. At this time, through the cooperation of the air inlet and the plug, the metered solder paste can be blown out of the sealing shell by using air push to complete accurate dotting amount. The single dotting amount is limited by physical volume, so as to avoid the influence of viscosity change on the extrusion amount, and further ensure the solder paste dotting quality of the device.

[0015] 2. When pushing the solder paste for dot coating, when air flows through the transmission hole, through the cooperation of the turbine and the stirring rack, the flowing air can drive the stirring rack to pre-treat the solder paste at the blocking position, so as to fully stir and mix. At the same time, through the cooperation of the guiding groove and the guiding block, the rotating rod can drive the stirring rack to reciprocate and shake during rotation. The combination of stirring and reciprocating movement can break the physical stratification of metal particles (such as tin powder) and flux in the solder paste, and make the two distribute more evenly through mechanical shear force, ensuring that the composition ratio of each portion of the solder paste is consistent. And the intermittent stirring can effectively balance the thixotropic characteristics of the solder paste through periodic shearing and pausing, making the viscosity of the solder paste within a suitable range, thus ensuring the dot coating effect of this device.

[0016] 3. When cleaning the residual solder paste, during the process of blowing and cleaning the surface of the combined housing using the annular air pipe, through the cooperation of the shielding shell and the connecting rod, the cleaning position can be protected and shielded to prevent the blown solder paste particles from splashing everywhere and contaminating the surface of the workpiece. At the same time, when the housing is opened, through the setting of the collar, the combined shielding shell can be driven to separate, avoiding blocking the dot coating step, thus avoiding affecting the production and processing of the varistor element. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the present invention; Figure 2 is a schematic diagram of the connection state of the extrusion tube and the inflation tank of the present invention; Figure 3 is a schematic diagram of the upward view of a part of the overall structure of the present invention; Figure 4 is a schematic diagram of the internal structure of the inflation tank of the present invention; Figure 5 is a schematic diagram of the internal structure of the extrusion tube of the present invention; Figure 6 is a schematic diagram of the structure of the first part of the quantitative conveying component of the present invention; Figure 7 is a schematic diagram of the structure of the second part of the quantitative conveying component of the present invention; Figure 8 is a schematic diagram of the structure of the third part of the quantitative conveying component of the present invention; Figure 9 is a schematic diagram of the structure of the intermittent stirring and vibrating component of the present invention; Figure 10 is a schematic diagram of the structure of the blowing and protecting component of the present invention.

[0018] In the figure: 1. Extrusion tube; 2. Transmission hole; 3. Through hole; 7. Installation groove; 8. Inflatable tank; 9. Installation frame; 10. Vent hole; 11. Piston; 12. Gas delivery pipe; 13. Annular gas transmission pipe; 14. Workbench; 15. Transverse movement component; 16. Longitudinal movement component; 4. Quantitative delivery component; 401. Fixed ring; 402. Metering port; 403. Dot coating head; 404. Support block 1; 405. Shaft rod; 406. Support block 2; 407. Torsion spring; 408. Sealing shell; 409. Connecting pull rope; 410. Through slot; 411. Sealing plate; 412. Groove 1; 413. Spring 1; 414. Air inlet hole; 415. Plug block; 416. Groove 2; 417. Connecting frame; 418. Spring 2; 419. Cover plate; 420. Connecting pipe; 5. Intermittent stirring and vibrating component; 501. Rotating rod; 502. Turbine; 503. Stirring frame; 504. Guide groove; 505. Guide block; 506. Cover shell; 507. Slide groove; 6. Blowing and protecting component; 601. Shielding shell; 602. Connecting rod; 603. Collar. Detailed implementation mode

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] Example 1, please refer to Figures 1 - 10 , the present invention provides a solder paste dot coating device for a varistor production line, including an extrusion tube 1, an inflatable tank 8, an installation frame 9, a vent hole 10, a piston 11, a gas delivery pipe 12, an annular gas transmission pipe 13, a workbench 14, a transverse movement component 15, and a longitudinal movement component 16. Transmission holes 2 are symmetrically opened at the top of the extrusion tube 1, and through holes 3 are symmetrically penetrated and opened at the bottom of the inflatable tank 8 corresponding to the transmission holes 2.

[0021] A quantitative delivery component 4 is arranged inside the extrusion tube 1.

[0022] Further, the quantitative delivery component 4 includes a fixing ring 401, and the outer wall of the fixing ring 401 is fixedly connected to the inner wall of the extrusion tube 1. A metering port 402 is penetrated and opened at the center of the end face of the fixing ring 401. A dotting head 403 is fixedly connected to the bottom of the extrusion tube 1, and a first support block 404 is symmetrically and fixedly connected to the bottom of the dotting head 403. A shaft rod 405 is rotatably connected inside the two first support blocks 404. Second support blocks 406 are symmetrically and fixedly connected to the outer walls of the two shaft rods 405, and a sealing shell 408 is fixedly connected to the bottom of the second support blocks 406. Torsion springs 407 are symmetrically arranged on the outer walls of the shaft rods 405. The closer side walls of the two second support blocks 406 are fixedly connected to the ends of the two torsion springs 407 away from each other. The closer ends of the two torsion springs 407 are fixedly connected to the outer walls on both sides of the first support block 404. Connecting pull ropes 409 are fixedly connected to the outer walls of the two sealing shells 408 away from each other.

[0023] Further, during use, first inject the solder paste into the extrusion tube 1, then insert the piston 11, and then screw the extrusion tube 1 into the bottom of the inflation tank 8 to complete the installation. When dotting, first place the circuit board to be dotted on the material board that can be lifted and moved on the workbench 14, and then find the dotting position through the cooperation of the transverse movement component 15 and the longitudinal movement component 16. After confirming the position, through the rising of the material board and the air supply pump outside the top of the workbench 14, the solder paste in the extrusion tube 1 is ejected to complete the dotting operation.

[0024] Further, for the operation of fixing the component, finding the point position, and pushing the dotting with air pressure more specifically before dotting the varistor component, reference can be made to the above-mentioned comparative document, and no further elaboration will be made here.

[0025] More specifically, in the embodiment, when moving and adjusting the spraying point position to prepare for dotting, first, a dotting head 403 is fixedly connected to the bottom of the extrusion tube 1, and a first support block 404 is symmetrically and fixedly connected to the bottom of the dotting head 403. A shaft rod 405 is rotatably connected inside the two first support blocks 404. Second support blocks 406 are symmetrically and fixedly connected to the outer walls of the two shaft rods 405, and a sealing shell 408 is fixedly connected to the bottom of the second support blocks 406. Torsion springs 407 are symmetrically arranged on the outer walls of the shaft rods 405. The closer side walls of the two second support blocks 406 are fixedly connected to the ends of the two torsion springs 407 away from each other, and the closer ends of the two torsion springs 407 are fixedly connected to the outer walls on both sides of the first support block 404. Thus, under normal circumstances, controlled by the torsion springs 407, the two sealing shells 408 are in a combined and sealed state, and at this time, the metering port 402 of the fixing ring 401 is in an open state.

[0026] When the gas filling tank 8 is filled with gas, as the pressure increases after filling, the piston 11 can be squeezed, and then the solder paste below the piston 11 can be pushed, so that the solder paste enters the space between the fixed ring 401 and the sealing shell 408 from the metering port 402. When the solder paste is full, if the solder paste continues to be injected at this time, it will exceed the elastic limit of the torsion spring 407, so that the sealing shell 408 begins to separate. At this time, a connecting pull rope 409 is fixedly connected to the outer walls of the two sealing shells 408 on the sides away from each other. And through grooves 410 are symmetrically penetrated through the inner wall of the metering port 402, and a sealing plate 411 is slidably connected to the inner wall of the through groove 410. At the same time, a first groove 412 is symmetrically opened on the inner wall of the extrusion tube 1 corresponding to the through groove 410, and a first spring 413 is fixedly connected to the inner wall of the first groove 412. And the close ends of the two first springs 413 are respectively fixedly connected to the outer walls of the two sealing plates 411 on the sides away from each other. At the same time, the other ends of the two connecting pull ropes 409 respectively pass through the inside of the extrusion tube 1 and are fixedly connected to the outer walls of the two sealing plates 411 on the sides away from each other. So when the metering port 402 is in the open state, the two sealing plates 411 are completely retracted into the through groove 410 at this time and compress the first spring 413.

[0027] When the sealing shell 408 begins to separate, the connecting pull rope 409 will be payed out. At this time, the first spring 413 rebounds and synchronously pushes the two sealing plates 411 to approach each other until they are completely closed, so as to be able to close the metering port 402 and complete the metering of one dot coating.

[0028] Then air inlet holes 414 are symmetrically opened on the upper and lower end faces of the fixed ring 401, and four plug blocks 415 are slidably connected to the inner walls of the four air inlet holes 414. And second grooves 416 are correspondingly opened on the inner walls of the four air inlet holes 414. At the same time, connecting frames 417 are symmetrically fixedly connected to the upper surfaces of the four plug blocks 415 corresponding to the second grooves 416. And the plug blocks 415 and the second springs 418 form a telescopic structure through the connecting frames 417. And a cover plate 419 is fixedly connected to the upper surface of the fixed ring 401 corresponding to the air inlet holes 414. At the same time, a communicating pipe 420 is fixedly connected to the top of the cover plate 419, and the other end of the communicating pipe 420 is fixedly connected to the inner wall of the extrusion tube 1 corresponding to the transmission hole 2. So when the metering port 402 is in the open state, at this time, since the sealing plate 411 is retracted into the through groove 410, the two plug blocks 415 above the fixed ring 401 are restricted, so that the gas in the gas filling tank 8 will not enter below the fixed ring 401 through the transmission hole 2, that is, the push dot coating operation will not be carried out in advance during the metering process.

[0029] When the metering port 402 is closed, the sealing plate 411 no longer restricts the two blocking blocks 415 above the fixed ring 401. At the same time, due to the closing of the metering port 402, the piston 11 will be difficult to continue moving downward and pushing. As a result, the gas in the inflatable tank 8 will preferentially flow through the transmission hole 2 and exert a pressure extrusion on the upper blocking block 415, causing the upper blocking block 415 to move downward and no longer block the upper air inlet hole 414. At this time, the gas will enter the first groove 412 and start to squeeze the lower blocking block 415 to move it downward, thus realizing the blowing of the metered solder paste by air push and discharging it from the sealing shell 408 to complete the accurate dotting amount. The physical volume is used to limit the single dotting amount, thus avoiding the influence of viscosity change on the extrusion amount, and further ensuring the solder paste dotting quality of this device.

[0030] When the air blowing completely pushes out the metered solder paste for dotting, the normal air pressure is restored in the inflatable tank 8. Thus, under the rebound of the second spring 418, the four blocking blocks 415 are driven to reset. At this time, the air no longer blows the sealing shell 408, so that under the rebound of the torsion spring 407, the two sealing shells 408 are driven to close again, thus reopening the metering port 402 for the next dotting.

[0031] Embodiment 2, on the basis of the above embodiment, an intermittent stirring component 5 is arranged inside the extrusion tube 1.

[0032] Further, the intermittent stirring component 5 includes a rotating rod 501. A mounting groove 7 is formed in the inner wall of the extrusion tube 1 corresponding to the penetration of the rotating rod 501, and the outer wall of the rotating rod 501 is arranged on the inner wall of the mounting groove 7. One end of the rotating rod 501 is fixedly connected with a turbine 502 corresponding to the transmission hole 2, and the other end of the rotating rod 501 is fixedly connected with a stirring frame 503 corresponding to the extrusion tube 1. A guiding groove 504 is formed on the outer wall of the rotating rod 501, and a guiding block 505 is fixedly connected to the inner wall of the mounting groove 7 corresponding to the guiding groove 504, and the bottom of the guiding block 505 fits and slides on the inner wall of the guiding groove 504.

[0033] More specifically, in the embodiment, when air flows through the transmission hole 2, one end of the rotating rod 501 is fixedly connected with a turbine 502 corresponding to the transmission hole 2, and the other end of the rotating rod 501 is fixedly connected with a stirring frame 503 corresponding to the extrusion tube 1. Thus, when air flows through the transmission hole 2, the turbine 502 will be used to drive the rotating rod 501 to rotate, and then drive the stirring frame 503 to stir the position of the solder paste above the fixed ring 401, so as to continuously stir the currently static solder paste and make it fully mixed.

[0034] Next, a guiding groove 504 is provided on the outer wall of the rotating rod 501, and a guiding block 505 is fixedly connected to the inner wall of the installation groove 7 corresponding to the guiding groove 504. The bottom of the guiding block 505 is slidably attached to the inner wall of the guiding groove 504. Thus, during the rotation of the rotating rod 501, through the cooperation of the guiding groove 504 and the guiding block 505, the rotating rod 501 can drive the stirring frame 503 to reciprocate and shake during rotation. The combination of stirring and reciprocating movement can break the physical stratification of metal particles such as tin powder and flux in the solder paste, and through mechanical shear force, the two are more evenly distributed, ensuring that the composition ratio of each portion of the solder paste is consistent.

[0035] Further, to avoid the viscosity of the solder paste being too low during dotting due to continuous stirring and ensure that the solder paste does not collapse after printing, when the dotting is completed, due to the reset of the blocking block 415, the gas in the gas filling tank 8 will not enter below the fixed ring 401 through the transmission hole 2, thus not driving the turbine 502 to rotate. Therefore, the metering process and the dotting process can be reasonably utilized. The intermittent stirring through periodic shearing and pausing can effectively balance the thixotropic properties of the solder paste, making the viscosity of the solder paste within a suitable range, thus ensuring the dotting effect of the device.

[0036] Further, since the guiding groove 504 is a notch that can achieve a positive and negative circulation shape, that is, the guiding groove 504 is divided into upper and lower parts on the surface of the rotating rod 501, one part realizes the forward movement of the rotating rod 501 and the other part realizes the backward movement of the rotating rod 501. Since the guiding block 505 will only be in one of the notches at the same time, there is a gap between the other notch and the installation groove 7. Therefore, to avoid leakage problems, a cover shell 506 is rotatably connected to the outer wall of the rotating rod 501, and the outer wall of the cover shell 506 is slidably connected to the inner wall of the installation groove 7. A sliding groove 507 is provided on the outer wall of the cover shell 506 corresponding to the guiding block 505, and the outer wall of the guiding block 505 is slidably attached to the inner wall of the sliding groove 507. Thus, through the setting of the cover shell 506, when the guiding block 505 is in one of the notches, the cover shell 506 can block the other notch, thus avoiding the problem of having a gap.

[0037] Embodiment 3, on the basis of the above embodiment, a blowing and protecting component 6 is provided on the outer wall of the extrusion tube 1.

[0038] Further, the blowing and protecting component 6 includes a shielding shell 601. A connecting rod 602 is hinged to the side of the two shielding shells 601 close to each other. One end of the two connecting rods 602 close to each other is fixedly connected to the bottom outer wall of the extrusion tube 1. The outer wall of the connecting pull rope 409 is slidably connected inside the shielding shell 601. A collar 603 is fixedly connected to the outer wall of the two connecting pull ropes 409, and the outer wall of the collar 603 is attached to and close to the inner wall of the shielding shell 601.

[0039] More specifically, in the embodiment, when the two enclosures 408 are separated for the dotting operation, at this time, under the pulling of the first spring 413, the connecting drawstring 409 will be pulled. At this time, collar 603 is fixedly connected to the outer wall of each of the two connecting drawstrings 409, and the outer wall of the collar 603 is in close contact with the inner wall of the shielding shell 601. Therefore, the connecting drawstring 409 can drive the collar 603 to move, so as to drive the two combined shielding shells 601 to separate, thus avoiding blocking the dotting step.

[0040] Then, when the dotting is completed and the metering process is carried out, at this time, the two enclosures 408 are combined, so as to bundle the two connecting drawstrings 409, so that the collar 603 no longer drives the shielding shell 601 to separate. Therefore, the two shielding shells 601 are combined under the action of gravity. At this time, during the metering process, the gas in the gas charging tank 8 starts to be pressurized. At this time, the valve of the gas delivery pipe 12 is opened, so as to transport part of the gas into the annular gas delivery pipe 13 to blow the residual solder paste on the surface of the enclosure 408. Thus, the cleaning position can be protected and shielded by the combined shielding shell 601, avoiding the splashing of the blown solder paste particles and polluting the surface of the workpiece.

[0041] Working principle: First, when the gas charging tank 8 is filled with gas, as the pressure increases after charging, the piston 11 can be extruded, and then the solder paste below the piston 11 can be pushed, so that the solder paste enters the space between the fixed ring 401 and the enclosure 408 from the metering port 402. When the solder paste is full, if the solder paste is continuously injected, it will exceed the elastic limit of the torsion spring 407. Therefore, the enclosure 408 starts to separate, and the connecting drawstring 409 is paid out. At this time, the first spring 413 rebounds and synchronously pushes the two sealing plates 411 to approach each other until they are completely closed, so as to seal the metering port 402 and complete the metering of one dotting; Then, when the metering port 402 is closed, at this time, the sealing plate 411 no longer restricts the two stoppers 415 above the fixed ring 401. At the same time, due to the closure of the metering port 402, it is difficult for the piston 11 to continue to move downward and push. Therefore, the gas in the gas charging tank 8 will preferentially flow through the transmission hole 2 and press the upper stopper 415, so that the upper stopper 415 moves downward and no longer blocks the upper air inlet hole 414. At this time, the gas will enter the first groove 412, and then start to press the lower stopper 415 to move downward, thus realizing the blowing of the metered solder paste by air and discharging it from the enclosure 408 to complete the accurate dotting amount; Next, when air flows through the transmission hole 2, the turbine 502 will be used to drive the rotating rod 501 to rotate, and then drive the stirring frame 503 to stir the solder paste located above the fixed ring 401, so as to continuously stir the currently static solder paste and make it fully mixed. At the same time, through the cooperation of the guiding groove 504 and the guiding block 505, the rotating rod 501 drives the stirring frame 503 to reciprocate during rotation. The combination of stirring and reciprocating movement can break the physical stratification of metal particles such as tin powder and flux in the solder paste, and make the distribution of the two more uniform through mechanical shear force, ensuring that the component ratio of each portion of the solder paste is consistent; Next, when the dot coating is completed and the metering process is carried out, the two enclosures 408 are combined at this time, so that the two connecting ropes 409 can be bundled, and the collar 603 no longer drives the shielding shell 601 to separate, so that the two shielding shells 601 are combined under the action of gravity. At this time, since the gas in the charging tank 8 starts to be pressurized during the metering process, the valve of the gas delivery pipe 12 is opened at this time, and part of the gas is transmitted into the annular gas delivery pipe 13 to blow the residual solder paste on the surface of the enclosure 408, so that the combined shielding shell 601 can protect and shield the cleaning position, avoiding the splashing of the blown solder paste particles and polluting the surface of the workpiece.

[0042] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solder paste dispensing device for a varistor production line, characterized in that: include: An extrusion tube (1), an air filling tank (8), a workbench (14), a transverse moving component (15), and a longitudinal moving component (16), wherein the transverse moving component (15) is installed at the rear side of the workbench (14), the longitudinal moving component (16) is installed in the transverse moving component (15), the longitudinal moving component (16) cooperates with the transverse moving component (15), and the extrusion tube (1) is installed in the longitudinal moving component (16); The top of the extruded tube (1) is symmetrically provided with a transmission hole (2), and the bottom of the inflatable tank (8) is symmetrically provided with a through hole (3) corresponding to the transmission hole (2); The extrusion tube (1) is provided with a quantitative conveying component (4) inside so that when pushing the solder paste for dispensing, the single dispensing amount is limited by physical volume, thereby avoiding the influence of viscosity changes on the extrusion amount; An intermittent stirring component (5) is provided inside the extrusion tube (1) to intermittently stir and mix the solder paste sufficiently to control the viscosity of the solder paste; The outer wall of the extrusion tube (1) is provided with a blowing protection component (6) to protect and shield the cleaning position when blowing away residual solder paste.

2. The solder paste dispensing device for a varistor production line according to claim 1, characterized in that: The quantitative delivery component (4) comprises a fixed ring (401), and the outer wall of the fixed ring (401) is fixedly connected to the inner wall of the extrusion tube (1), and a metering port (402) is provided through the center of the end face of the fixed ring (401), and a dot coating head (403) is fixedly connected to the bottom of the extrusion tube (1), and a support block (404) is symmetrically fixedly connected to the bottom of the dot coating head (403), and two shafts (405) are rotatably connected inside the two support blocks (404), and the outer walls of the two shafts (405) are symmetrically fixedly connected to the dot coating head (403). It is connected to support block 2 (406), and the bottom of support block 2 (406) is fixedly connected to a shell (408), the outer wall of the shaft rod (405) is symmetrically provided with torsion springs (407), one side wall of the two support blocks 2 (406) close to each other is fixedly connected to one end of the two torsion springs (407) away from each other, one end of the two torsion springs (407) close to each other is fixedly connected to the outer walls of both sides of support block 1 (404), and one side outer wall of the two shells (408) away from each other is fixedly connected to a connecting rope (409).

3. The solder paste dispensing device for a varistor production line according to claim 2, characterized in that: The inner wall of the metering port (402) is symmetrically provided with a through groove (410) extending therethrough, and the inner wall of the through groove (410) is slidably connected to a sealing plate (411); the inner wall of the extrusion tube (1) is symmetrically provided with a groove one (412) corresponding to the through groove (410), and the inner wall of the groove one (412) is fixedly connected to a spring one (413); the two ends of the springs one (413) that are close to each other are fixedly connected to the outer walls of the two sealing plates (411) that are away from each other; the other ends of the two connecting ropes (409) pass through the interior of the extrusion tube (1) and are fixedly connected to the outer walls of the two sealing plates (411) that are away from each other; the upper and lower end surfaces of the fixing ring (401) are symmetrically provided with air inlet holes (414), and the inner walls of the four air inlet holes (414) are all slidably connected to blocks (415).

4. The solder paste dispensing device for a varistor production line according to claim 3, characterized in that: The inner walls of the four air inlet holes (414) are provided with grooves 2 (416) correspondingly; the upper surfaces of the four blocking blocks (415) are symmetrically fixedly connected to connecting frames (417) corresponding to the grooves 2 (416); the inner surface of the top side of the connecting frame (417) is fixedly connected to spring 2 (418), and the other end of spring 2 (418) is fixedly connected to the inner wall of groove 2 (416); the blocking blocks (415) and spring 2 (418) form a telescopic structure through the connecting frame (417); the upper surface of the fixing ring (401) is fixedly connected to a cover plate (419) corresponding to the air inlet holes (414), and the top of the cover plate (419) is fixedly connected to a connecting pipe (420); the other end of the connecting pipe (420) is fixedly connected to the inner wall of the extrusion tube (1) corresponding to the transmission hole (2).

5. The solder paste dispensing device for a varistor production line according to claim 4, characterized in that: The intermittent stirring component (5) comprises a rotating rod (501); an installation groove (7) is formed through the inner wall of the extrusion tube (1) corresponding to the rotating rod (501); the outer wall of the rotating rod (501) is arranged on the inner wall of the installation groove (7); one end of the rotating rod (501) is fixedly connected to a turbine (502) corresponding to the transmission hole (2); the other end of the rotating rod (501) is fixedly connected to a stirring frame (503) corresponding to the extrusion tube (1); a guide groove (504) is formed on the outer wall of the rotating rod (501); a guide block (505) is fixedly connected to the inner wall of the installation groove (7) corresponding to the guide groove (504); and the bottom of the guide block (505) is slidably fitted on the inner wall of the guide groove (504).

6. The solder paste dispensing device for a varistor production line according to claim 5, characterized in that: The outer wall of the rotating rod (501) is rotatably connected to a cover shell (506), and the outer wall of the cover shell (506) is slidably connected to the inner wall of the mounting groove (7). The outer wall of the cover shell (506) is provided with a sliding groove (507) corresponding to the guide block (505), and the outer wall of the guide block (505) slides in contact with the inner wall of the sliding groove (507).

7. The solder paste dispensing device for a varistor production line according to claim 6, characterized in that: The blow-off protection component (6) comprises a shielding shell (601), a connecting rod (602) is hinged on one side of two shielding shells (601) that are close to each other, and one end of the two connecting rods (602) that are close to each other is fixedly connected to the bottom outer wall of the extrusion tube (1), and the outer wall of the connecting rope (409) is slidably connected to the inside of the shielding shell (601), and the outer walls of the two connecting ropes (409) are fixedly connected to a ring (603), and the outer wall of the ring (603) is in close contact with the inner wall of the shielding shell (601).

8. The solder paste dispensing device for a varistor production line according to claim 1, characterized in that: The solder paste dispensing device further comprises a mounting frame (9), a vent (10), a piston (11), a gas delivery pipe (12), and an annular gas delivery pipe (13); The top end of the extrusion tube (1) is threadedly connected to the bottom of the gas tank (8), the outer wall of the gas tank (8) is rotatably mounted inside the mounting frame (9), the vent (10) is opened at the bottom of the gas tank (8), the piston (11) is slidably mounted on the inner wall of the extrusion tube (1), one end of the gas delivery tube (12) is fixedly mounted on one side of the outer wall of the gas tank (8), and the annular gas delivery tube (13) is mounted on the outer wall of the coating head (403) corresponding to the sealing shell (408).

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